Blockchain Papers

R. G. Collingwood

The argument of this paper may be summarized as follows. Causal propositions (propositions of the type “x causes y”) are ambiguous. Such a proposition may have any one of three meanings (possibly more; but three is enough for this paper). The ambiguity, however, is of a rather odd kind. Sense I, which is historically the original sense, is pre-supposed by the others, and remains strictly speaking the one and only “proper” sense. When we assert propositions containing the word cause in senses II and III, we are “saying” one thing and “meaning” another; we are describing certain things as if they were things of a kind which we do not actually believe them to be. This always has an element of danger in it: the danger of inadvertently beginning to “mean” what one had only intended to “say”, i.e., of thinking that things are what we describe them as if they were. This danger is much worse when our “metaphors” get “mixed”. This is what has happened with the so-called “idea of causation” from the time of Kant onwards. It is a confusion of certain characteristics belonging to sense II with certain others belonging to sense III. Nothing can be done, therefore, towards clearing up our minds about causation, by merely analysing the idea as it stands and detailing the various elements it contains; for these elements are mutually contradictory. We must carry the process further, by segregating the elements under different heads, and distinguishing these as different “senses” of the word. But even this is not enough. A further step in the process is needed: namely a critical discussion of each “sense” taken singly. When this is done it will be found that the best way of avoiding confusion will be to restrict our use of the word cause to occasions on which it is used in its “proper” sense, No. I; that on the occasions on which we use it in sense II we should be wise to use instead the terminology of means and ends; and that when we use it in sense III we should do better to speak of “laws” and their “instances”. In the sense of the word that which is is the and of a and and to do it means a for we may to in the kind of in This is the time a and sense of the word with its and in and of the in of in and in A in a in causes of This not that the to the that with and it that on the up to In the sense we that a causes a to a that causes to from an It is not only a sense, it is of In is the word for as when the the of with the and the of have it that this is a use of the word and from what sense III, i.e., the sense in which one thing in is to be the cause of This is not the sense is the of the as can for will the in the and the in and and the cause in the II and III have of it by a process which in the A cause in this sense of a cause and a The is a of things the is a of things to be of these be a cause if the were A to a certain may be to by a about the of that but this not cause to to in the of an a to a not cause to in a certain if in that The is not a of things as it is a of things by the in to a a certain of the cause of is not this as it is this as to the in by The is not a as it is an A is to in a certain way not by to in that way it is to to but by to in that may be to the of but is not of this kind may the of a and in as the that a certain of things as when a of a certain the to a certain This is to the to do a certain to do The however, is an it not be done not be the it of A causes to do an is and not is a in and is for is a which A to by certain certain is the is the proposition that the by and the proposition that a in of and is for the the proposition the in this A is to the for the This not that a is a which be an which do when they speak of It means that is for the A is for the of certain to certain to the When a of a on its do is not is as an This is what when of the and A is to when about the is not on from and are In this in which a is to is not It has a and a But has done for the of the and the which in the is to cause has done for can be to cause as as to do in that the of be an which to an of on the of and has as only will not what they by the word In sense in sense I, the word cause an idea to but the in this is an intended to not but things in In this sense, the of an in is the to by which we can we to to a and it we can certain of our we about for its The is the cause of an means in this can we This sense of the word may be as follows. A cause is an of things which it is in our to and by which we can that cause it is to be. 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The of in the is a cause in sense III, is in the of sense III. The about sense III is to what is by that a cause its When is used of senses and II we what it in sense it means that a for in sense II that is means of But what it of it in sense are to this which may be the and The means A on this is a and its to its is the of to a When that means on this that and is the kind of which one has the of one of a the of the and the one as to the of one must that in a the of the can be it and even when it on the of a The therefore, that the cause is the not only in the sense that if the cause the actually but that if the cause is the is to to the of a thing can the by thinking the of Nothing in the of is This is in a in the sense if to a of in which the for causes means a for is to from This in what to to be a of and as is a in to the it that the is But the of causation, it may be as the of a be as an of the propositions by it were these propositions have to be as one that they can be by that by the so-called to be in the so-called it is this is that the what causes a and what a cause have to be by and the of a of the type not an of propositions of the type “x causes propositions of the type “x but the of propositions in that kind of and the use of propositions in the of and propositions not propositions be the of in these propositions This not be by that the in which propositions are Such a that the idea of is a idea which when will the different idea of This to be the of the of and if to it do not to but must that it not from the what the idea is that its had to the means of the this one be taken for will that the proposition “x means merely the have to be with and not in the will be with In the for and we from the of to the of the we from the of these propositions to the that the proposition the have to be with is not what we by “x but is only the on the of which we assert the different proposition “x if means of it must be that is that is is we assert on the of of what to that is what should to assert a we must from the of the propositions to the this is we to assert but on the occasions when we do assert them we to be namely to our has by in a of to which have to but and to for it and to is a of a that it is for of its argument This will the In as it to that in sense III a cause and But to of what to on the a proposition to be even that the in to a in if is a of and of may be an even if they are it may not be to them are the of any we that a will always be a that is in the of a the the which have for do not intended to and But if has a as when on for a paper get of it this i.e., to a paper on this is for to a the word is not a of a it to a of in sense I, and means that has to This sense of in which it to is to the sense which is not only in sense and sense II of the word cause but in sense III The that can be and of the that happened only the of on the that are from one original and that be not in the sense of of by but in the sense of a in it be on of and on to the cause of an but it to be that has a even we what its cause and if a is to the that an has it may may not be but it be a of of for it that that when we use the word in sense III we to by it different from and of in the and in the and that this and is in the of that this is We have to the which we when we found the idea in sense and we have to it in the what is this idea It to be that it is from our of occasions on which we have others to in certain by them in their to the that they are in of a kind that only by can they the we them to and occasions in which we have is an idea from our and in what is a way not only to our with things in II of the word but to the which these things have Causal propositions in sense III are of in The we are in the of these of that they are the of the that it up in with the of to which in sense II of the word but that in this the a of a can be to certain in by certain means to them and if is as of the but it will that will be as about certain things in by the of certain a step in the argument if we to it we should is a thing in by as a means of we to be a in of its but as in the of that must be. in that that which is by the word that word not be as a to and be the is for not the but the This not the in a of causes of the but a cause of a as from The a of the on this it that in certain for the of certain these a in certain to with a kind of and these the of and that of to the is and is a kind of one thing in thing in The and are used and to a sense of and for the of things is taken as the of these causes is a of and is a of This the in which our of and in which the to that were in the and when the of and by a the word cause not a it a and its in these when we to and the to we as a of a taken to in a kind of which to one to as to that a cause is of that in which its is if what is is a of a certain that but by the and of the it is that for the idea of is the idea of by thing which if not under this this different by This of one thing in by is the of is that a by and in have to be 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may its The in has a of one the with its on causes in sense the of causes sense with the of and the of the cause as an in time to its the one thing in which has found namely the that what to a not a as the a which has the that has a the cause of is a and this is to not from but a be by that has a It be if were used in sense In sense II it is in that is not if we for of not to is what Kant a have with the idea in a must be used in sense III. But what can be for can only that the of cause with of that and that a of the of The cause of an can be a III, only when cause is used in sense in the proposition “x causes means be an may have but its be The of a the a these not the only that can is an that is with is in a of is a from The of the is an by the Kant has to that in the propositions the word is used in different is therefore, to it a the to the as a of of of and a certain of the in which had by when to sense III and get to sense the of cause is not only but actually the in of a of cause as can be from with with the of cause to and on a of causes a to have that the only sense of the word cause is sense III. But when as of from to causation, for the of i.e., the of the is it for in of sense II in any on the from of as as to the sense in which the word cause is will to paper the of is that has on the the The of this paper by the of on the is to a of the of has for that the of causation” is and and that in propositions about causes have are by propositions about to to and to that from it may be only in however, a a of the of time which cause and we the may this which the if is used in the sense, this proposition is for it means that is for a certain may be which is must be in the sense. But if is to is the in the sense, of are as a is is but that not that is in that sense, its the only to a is from one sense to the when the in and that the cause it the that causes i.e., that they are in way to is that as not that causes are in way to further and that this is of the word by But what in a is not this it is the cause and have this The has by and the confusion of sense II and sense III is of a the of a proposition of the causes is to a proposition of the the must be taken to not to a of of but to the of the of the word that the word is used in sense III, the sense. But the that it is used in sense for only in that sense is it that in a proposition of the type causes and are is with a idea of in which one element is from the characteristics of sense II and from of sense III. It is not therefore, that even to any proposition must be a for a proposition of the as must be in and is that a proposition which is in is is a of which that is thing as from of a that they in but and of a of this has a on The of and its The which is the of this is the of that the that is by what has This is and the for means the belonging to an to a of have a that therefore, a this as belonging to the of The is for the a namely of of that must have a cause and that this cause must be a but that our of this is have only to what by a in to that this is the that Kant on to will not that we a on as an as a which we will is that will of and to the that one is that is of to the that which is to which it to as it to with happened that but them that we of that is a that it be is not do not that things are as they are they were as they were. But do The are one in an of which to be of them has to any Kant the propositions of which this is are that as to we a of it The have in a to which have to by the word in This is that a it and have it the The word to a of the It is not used by a is thinking is to the is this of which are and what are its have the of it when in they are of their but when they to be to the to of it as have the use of is an will are It have any of the have to that the is is the “idea of causation” which for is the which this our to not only their but their

Gyan Prakash, B. N. VYAS, Product Design Specialist, Cognizant Technology Solutions, Kolkata, India

Cloud-based outsourced storage relieves the client's load for storage management and maintenance by providing a comparably low-cost, scalable, locationindependent platform. Though, the information that clients no longer have physical control of data specifies that they are facing a potentially formidable risk for missing or corrupted data. To avoid the security risks, inspection services are serious to ensure the integrity and availability of outsourced data and to achieve digital forensics and reliability on cloud computing. Provable data possession (PDP), which is a cryptographic method for validating the reliability of data without retrieving it at an untrusted server, can be used to realize audit services. In this project, profiting from the interactive zero-knowledge proof system, the construction of an interactive PDP protocol to prevent the fraudulence of prover (soundness property) and the leakage of verified data (zero knowledge property).To prove that our construction holds these properties based on the computation Diffie-Hellman assumption and the rewindable black-box knowledge extractor. An efficient mechanism on probabilistic queries and periodic verification is proposed to reduce the audit costs per verification and implement abnormal detection timely. Also, we present an efficient method for choosing an optimal parameter value to reduce computational overheads of cloud audit services.

Saramago, Rodrigo Q., Meling, Hein, Jehl, Leander N.

A certification system is responsible for issuing digital credentials, which attest claims about a subject, e.g., an academic diploma. Such credentials are valuable for individuals and society, and widespread adoption requires a trusted certification system. Trust can be gained by being transparent when issuing and verifying digital credentials. However, there is a fundamental tradeoff between privacy and transparency. For instance, admitting a student to an academic program must preserve the student’s privacy, i.e., the student’s grades must not be revealed to unauthorized parties. At the same time, other applicants may demand transparency to ensure fairness in the admission process. Thus, building a certification system with the right balance between privacy and transparency is challenging. This paper proposes a novel design for a certification system that provides sufficient transparency and preserves privacy through selective disclosure of claims such that authorized parties can verify them. Moreover, unauthorized parties can also verify the correctness of the certification process without compromising privacy. We achieve this using an incremental Merkle tree of cryptographic commitments to users' credentials. The commitments are added to the tree based on verifying zero-knowledge issuance proofs. Users store credentials off-chain and can prove the ownership and authenticity of credentials without revealing their commitments. Further, our approach enables users to prove statements about the credential’s claims in zero-knowledge. Our design offers a cost-efficient solution, reducing the amount of linkable on-chain data by up to 79% per credential compared to prior work, while maintaining transparency.

Reinhold Burger, Albert Heinle

In this paper we present a new primitive for a key exchange protocol based on multivariate non-commutative polynomial rings, analogous to the classic Diffie-Hellman method. Our technique extends the proposed scheme of Boucher et al. from 2010. Their method was broken by Dubois and Kammerer in 2011, who exploited the Euclidean domain structure of the chosen ring. However, our proposal is immune against such attacks, without losing the advantages of non-commutative polynomial rings as outlined by Boucher et al. Moreover, our extension is not restricted to any particular ring, but is designed to allow users to readily choose from a large class of rings when applying the protocol. Our primitive can also be applied to other cryptographic paradigms. In particular, we develop a three-pass protocol, a public key cryptosystem, a digital signature scheme and a zero-knowledge proof protocol.

Joseph A. Akinyele, Gilles Barthe, Benjamin Grégoire, Benedikt Schmidt · 5 authors

Many algorithms admit very efficient batch versions that compute simultaneously the output of the algorithms on a set of inputs. Batch algorithms are widely used in cryptography, especially in the setting of pairing-based computations, where they deliver significant speed-ups. Auto Batch is an automated tool that computes highly optimized batch verification algorithms for pairing-based signature schemes. Thanks to finely tuned heuristics, Auto Batch is able to rediscover efficient batch verifiers for several signature schemes of interest, and in some cases to output batch verifiers that outperform the best known verifiers from the literature. However, Auto Batch only provides weak guarantees (in the form of a LaTeX proof) of the correctness of the batch algorithms it outputs. In this paper, we verify the correctness and security of these algorithms using the Easy Crypt framework. To achieve this goal, we define a domain-specific language to describe verification algorithms based on pairings and provide an efficient algorithm for checking (approximate) observational equivalence between expressions of this language. By translating the output of Auto Batch to this language and applying our verification procedure, we obtain machine-checked correctness proofs of the batch verifiers. Moreover, we formalize notions of security for batch verifiers and we provide a generic proof in Easy Crypt that batch verifiers satisfy a security property called screening, provided they are correct and the original signature is unforgeable against chosen-message attacks. We apply our techniques to several well-known pairing-based signature schemes from the literature, and to Groth-Sahai zero-knowledge proofs.

Melissa Chase, Markulf Kohlweiss, Anna Lysyanskaya, Sarah Meiklejohn

A signature scheme is malleable if, on input a message and a signature, it is possible to efficiently compute a signature on a related message, for a transformation that is allowed with respect to this signature scheme. In this paper, we first provide new definitions for malleable signatures that allow us to capture a broader range of transformations than was previously possible. We then give a generic construction based on malleable zero-knowledge proofs that allows us to construct malleable signatures for a wide range of transformation classes, with security properties that are stronger than those that have been achieved previously. Finally, we construct delegatable anonymous credentials from signatures that are malleable with respect to an appropriate class of transformations (that we show our malleable signature supports). The resulting instantiation satisfies a stronger security notion than previous schemes while also scaling linearly with the number of delegations.

Fuchun Guo, Yi Mu, Willy Susilo

In this paper, we propose a novel cryptographic notion called subset membership encryption (SME), and provide a very efficient SME scheme. Given a system parameter generated by an encryptor (Alice), a decryptor (Bob) generates a randomized privacy-preserved attribute token P(G) from a set of attributes G. A message is encrypted using an attribute set A chosen by Alice and P(G) provided by Bob. It requires that A is a subset of G for Bob to decrypt the message. We propose a very efficient SME scheme, where both the size of P(G) and ciphertext are short and independent of G and A. In particular, it has three useful and practical applications to oblivious transfer as follows. 1) k-Out-of-n Oblivious Transfer (OT): SME can be naturally applied to a two-round OT, which features a great communication efficiency especially for the receiver, where the receiver only sends two group elements to the message sender. 2) Priced Oblivious Transfer (POT): Our POT protocol allows a buyer to purchase any number of items in each transaction and hide selected items, price and balance from the vendor. In comparison with previous POT protocols, our protocol is more flexible and eliminates the restriction that a buyer can only purchase one item in a transaction. Our POT scheme is very efficient since it does not require any zero-knowledge proof or homomorphic encryption. 3) Restricted Priced Oblivious Transfer (RPOT): We introduce a novel POT named RPOT where a vendor can set restrictions on items or prices in POT. For example, a seller could offer a discounted price to those buyers who have purchased some specific items previously from the same seller.

Samantha Xu

Consider the radial nonlinear wave equation $-\partial_t^2 u + Δu = u^3$, $u :\mathbb{R}_t \times \mathbb{R}_x^3 \to \mathbb{R}$, $u(t,x) = u(t,|x|)$. In this paper, we construct a Gibbs measure for this system and prove its invariance under the flow of the NLW. In particular, we are in the infinite volume setting. For the finite volume analogue, specifically on the unit ball with zero boundary values, an invariant Gibbs measure was constructed by Burq, Tvetkov, and de Suzzoni as a Borel measure on super-critical Sobolev spaces. In this paper, we advocate that the finite volume Gibbs measure be considered on a space of weighted Hölder continuous functions. The measure is supported on this space and the NLW is locally well-posed there, a counter-point to the Sobolev super-criticality noted by Burq and Tzvetkov. Furthermore, the flow of the NLW leaves this measure invariant. We use a multi-time Feynman--Kac formula to construct the infinite volume limit measure by computing the asymptotics of the fundamental solution of an appropriate parabolic PDE. We use finite speed of propagation and results from descriptive set theory to establish invariance of the infinite volume measure. To the best of our knowledge, this paper provides the first construction and proof of invariance of a Gibbs measure in infinite volume outside of the 1D case.

Florian Kerschbaum, Martín Beck, Dagmar Schönfeld

Privacy is of the utmost importance in genomic matching. Therefore a number of privacy-preserving protocols have been presented using secure computation. Nevertheless, none of these protocols prevents inferences from the result. Goodrich has shown that this resulting information is sufficient for an effective attack on genome databases. In this paper we present an approach that can detect and mitigate such an attack on encrypted messages while still preserving the privacy of both parties. Note that randomization, e.g.~using differential privacy, will almost certainly destroy the utility of the matching result. We combine two known cryptographic primitives -- secure computation of the edit distance and fuzzy commitments -- in order to prevent submission of similar genome sequences. Particularly, we contribute an efficient zero-knowledge proof that the same input has been used in both primitives. We show that using our approach it is feasible to preserve privacy in genome matching and also detect and mitigate Goodrich's attack.

Nesrine Kaaniche, Ethmane El Moustaine, Maryline Laurent

Recent technological advances have given rise to the popularity and success of cloud storage. However, the prospect of outsourcing an increasing amount of data to a third party and the abstract nature of the cloud foster the proliferation of security and privacy challenges, namely, the remote data possession checking. This paper addresses this critical security concern, when storing sensitive data in a cloud storage service, and the need for users to trust commercial cloud providers. It proposes a deterministic Proof of Data Possession (PDP) scheme based on Interactive Proof System(IPS) and an original usage of the GPS scheme. Our approach has several advantages. First, it supports public verifiability which releases data owners from the burden of a periodical verification. Second, it provides constant communication complexity, where the exchanged messages between the storage server and the client are composed of constant number of group elements. Third, our solution is efficient and provably secure, as it is resistant to the fraudulence of the prover and the leakage of verified data.

Andris Ambainis, Ansis Rosmanis, Dominique Unruh

Quantum zero-knowledge proofs and quantum proofs of knowledge are inherently\ndifficult to analyze because their security analysis uses rewinding. Certain\ncases of quantum rewinding are handled by the results by Watrous (SIAM J\nComput, 2009) and Unruh (Eurocrypt 2012), yet in general the problem remains\nelusive. We show that this is not only due to a lack of proof techniques:\nrelative to an oracle, we show that classically secure proofs and proofs of\nknowledge are insecure in the quantum setting.\n More specifically, sigma-protocols, the Fiat-Shamir construction, and\nFischlin's proof system are quantum insecure under assumptions that are\nsufficient for classical security. Additionally, we show that for similar\nreasons, computationally binding commitments provide almost no security\nguarantees in a quantum setting.\n To show these results, we develop the "pick-one trick", a general technique\nthat allows an adversary to find one value satisfying a given predicate, but\nnot two.\n

Andris Ambainis, Ansis Rosmanis, Dominique Unruh

Quantum zero-knowledge proofs and quantum proofs of knowledge are inherently difficult to analyze because their security analysis uses rewinding. Certain cases of quantum rewinding are handled by the results by Watrous (SIAM J Comput, 2009) and Unruh (Eurocrypt 2012), yet in general the problem remains elusive. We show that this is not only due to a lack of proof techniques: relative to an oracle, we show that classically secure proofs and proofs of knowledge are insecure in the quantum setting. More specifically, sigma-protocols, the Fiat-Shamir construction, and Fischlin's proof system are quantum insecure under assumptions that are sufficient for classical security. Additionally, we show that for similar reasons, computationally binding commitments provide almost no security guarantees in a quantum setting. To show these results, we develop the "pick-one trick", a general technique that allows an adversary to find one value satisfying a given predicate, but not two.

Craig Gentry, Jens Groth, Yuval Ishai, Chris Peikert · 6 authors

No abstract is available for this record.

Patrick Delorme

Yiannis Sakellaridis and Akshay Venkathesh have determined, when the group\n$G$ is split and the field $\\F$ is of characteristic zero, the Plancherel\nformula for any spherical space $X$ for $G$ modulo the knowledge of the\ndiscrete spectrum.\n The starting point is the determination of good neighborhoods at infinity of\n$X/J$, where $J$ is a small compact open subgroup of $G$. These neighborhoods\nare related to "boundary degenerations" of $X$. The proof of their existence is\nmade by using wonderful compactifications.\n In this article we will show the existence of such neighborhoods assuming\nthat $\\F$ is of characteristic different from 2 and $X$ is symmetric. In\nparticular, one does not assume that $G$ is split. Our main tools are the\nCartan decomposition of Benoist and Oh, our previous definition of the constant\nterm and asymptotic properties of Eisenstein integrals due to Nathalie Lagier .\n Once the existence of these neighborhoods at infinity of $X$ is established,\nthe analog of the work of Sakellaridis and Venkatesh is straightforward and\nleads to the Plancherel formula for $X$.\n

Wolfgang Johannsen

BIOLOGY has evidently borrowed the terms “heredity” and “inheritance” from everyday language, in which the meaning of these words is the “transmission” of money or things, rights or duties—or even ideas and knowledge —from one person to another or to some others: the “heirs” or “inheritors.” The transmission of properties—these may be things owned or peculiar qualities—from parents to their children, or from more or less remote ancestors to their descendants, has been regarded as the essential point in the discussion of heredity, in biology as in jurisprudence. Here we have nothing to do with the latter; as to biology, the students of this science have again and again tried to conceive or “explain” the presumed transmission of general or peculiar characters and qualities “inherited” from parents or more remote ancestors. The view of natural inheritance as realized by an act of transmission, viz., the transmission of the parent's (or ancestor's) personal qualities to the progeny, is the most naive and oldest conception of heredity. We find it clearly developed by Hippocrates, who suggested that the different parts of the body may produce substances which join in the sexual organs, where reproductive matter is formed. Darwin's hypothesis of “pangenesis” is in this point very consistent with the Hippocratic view, the personal qualities of the parent or the ancestor in question being the heritage. Also the Lamarckian view as to the heredity of “acquired characters” is in accordance with those old conceptions. The current popular definition of heredity as a certain degree of resemblance between parents and offspring, or, generally speaking, between ancestors and descendants, bears the stamp of the same conceptions, and so do the modern “biometrical” definitions of heredity, e.g., as “the degree of correlation between the abmodality of parent and offspring.” In all these cases we meet with the conception that the personal qualities of any individual organism are the true heritable elements or traits! This may be characterized as the “transmission-conception” of heredity or as the view of apparent heredity. Only superficial instruction can be gained by working on this basis. Certainly, medical and biological statisticians have in modern times been able to make elaborate statements of great interest for insurance purposes, for the “eugenics-movement” and so on. But no profound insight into the biological problem of heredity can be gained on this basis, for the transmission-conception of heredity represents exactly the reverse of the real facts, just as the famous Stahlian theory of “phlogiston” was an expression diametrically opposite to the chemical reality. The personal qualities of any individual organism do not at all cause the qualities of its offspring; but the qualities of both ancestor and descendant are in quite the same manner determined by the nature of the “sexual substances”—i.e., the gametes—from which they have developed. Personal qualities are then the reactions of the gametes joining to form a zygote; but the nature of the gametes is not determined by the personal qualities of the parents or ancestors in question. This is the modern view of heredity. The main result of all true analytical experiments in questions concerning genetics is the of the transmission-conception of heredity, and the different of as as have in that to the same point of view, the as we may the conception of heredity just Here we can not the of the ideas concerning heredity, not even in the but it be as a that a very great of the terms by the modern biological have been the of the and that the of and are not from that old may be words as “transmission” and The science of genetics is in a an science just as the in the times of who the an in chemical The as have the modern view of heredity, not from the old “transmission-conception” as but it from the of and who with more or less tried to the the great of the for the in of more in of and in of but have suggested that the elements for inheritance elements of or of the different or of the individual from the in question. has an elaborate hypothesis of heredity, that of the are of in the of a in the of a being in some the of an or a of that in the to organs, and that of the are of parts of the inheritance in question are the or ideas may have some interest as of the but they have no in the of is evidently the a view of heredity any The of the by and but as an expression of the insight by and is in the degree a all the of and it may is a that is not we to even to but that it may be by of the to the current This is the it is to a in all cases where or are being developed. terms are by their in or and from which they of not to the have the terms and and some as and to be in the science of The is nothing but a very with and it may be as an expression for the or in the by modern is the of all the in a or in a a is by the of this is in one point and the of the gametes in question in one point from to the nature of the it is as of no to any but that the a is from The have the great of being in their In accordance with this quite natural the of the may be to the of the We do not a but we are able to or in these the and The very by as may be with in so as the is the of the of the in question. these are is by the as of The the and the in the of the individual the organism is a and its reactions are determined by its with the of all may it be or the is with the The can be by the qualities and reactions of the in question. that some of are different then these produce more or less as to the personal qualities of the individual of of different it be quite to they have or have not the same we to be We may find that the in question so that they to the same the current of this or we may in cases that they a so that or more different may be of by or by of or may be characterized as are real the or of are again and again the for in the are and the of the of as to and characters of the has been the of natural which was a science of by the of the has of with in its concerning The of by from one to another have and the of are the in very but that is an point may be in one which the the view the of the in different are the main and the transmission-conception we may this conception as a in to the the has been gained in and The to an of the or the may an of the of the The of has its most in all where the are where with the or by to one this being characterized by the of the of any of and so This is to the all between the different in question the of and and have the point for as a of may be as the from one by is a nothing as to the qualities of the in question. to be (or even the of a of can be as as are very of be quite in and in to one and the same the was but The of the is a main point in the of of nature is not at all a for the of with is the of which the of have some The of from has been the for the that is not able to the nature of The of the of a by from to in the by the to the a of in the a great of those is for the of the of any be for the result of the no or have been at a in which is no as to the in have no This result has in been by in Here may the experiments of with experiments which have been quite of and which have been of great for the and of the The of these experiments has been on the that the but this matter to of no in the The that of and of in the of as a is a of the Also experiments with the of and the of as to may be as for this has at the same as to the by The famous of and its by to have the of in by the of the of in these of correlation have been in their of may be in but they have nothing at all to do with genetics or general are for insight into the nature of heredity. to heredity, it is a expression for a The are the in but generally the in is In no of the can be all of the as to the of and may even a that the is in in heredity speaking, a of the “transmission-conception” and nothing The characters of ancestors as as of are both in quite the same manner reactions of the of the gametes in question. between an ancestor and one or more of as heredity is in the as we have to the is not a of the personal of any The of a or a may be with a This in of its realized but not in of the of its it may be with the of gametes and its is its which are determined by its In the in are in of are The it is to by of any individual the to which it the the as as in the no The is an view of the reactions of as as true heredity is This view is an to the chemical view, as chemical have no is and in the same may be the of its or the of its that it is to this of heredity in its to the to the of we meet with true viz., the of and all of is a very great but is quite different from heredity. may be of and the of is not an is in to as of some of or in their of the of from more Certainly, of of and of all on by of with the not the but their But all this has nothing at all to do with the biological of heredity. is of to that the of by has in but this nothing as to for which is The very form of the may be to be in all its in cases of experiments in In nature and even in the chemical the chemical are not to be in quite The of a may be by to the with the we the question the of a may not be by some or from the individual organism in which the was developed. Here we meet with the cases of heredity, e.g., the of the gametes or as may be in certain cases of and of heredity may have the of or but they do not at all with the of heredity. In cases as that by viz., the “heredity” of a form of by “transmission” the of the not this may at the be as we have to do with a of the or the in and that may be the for the of heredity the which no or a The of being as quite it may be very to clearly from determined which the form of heredity both and The and not to be in with of any may be to in the and consistent of the that may be characterized as by or it be that as as are no between and of is but not is a The of or, is of for the question of the inheritance of “acquired and are in the most both the of the with the the with the of the of the in question. The of with and the experiments of that of the are by as no with has any for the Lamarckian view, the most to the experiments by for the of their have not but have the of some by and are at the same the in personal qualities being to the in are their of it is that their in biology as ideas has been most some cases of apparent of may have with Lamarckian e.g., of by as “the that has of the was that with analytical that has the great But at the the from the is in on the of for are for the the that the was not at all the of to point the of as to the of in The and more the The of or of in may be for the of not to we have an times by viz., the of with as it has been that we have the essential The in have been the the been from the and to the result be a of the those The to to no for the The are a to of with and in the of this are to any questions of and they make as to the nature of heredity and has the of as a be an in heredity. to the of it has been by e.g., that is a old and This is quite not in a manner the of but even tried a to But it can not be that the of as a true analytical as an of in as a at any and of a from this analytical been in the times of or it even been in by the the real of have been by the of The may then be characterized as and may to a certain with the most of of with a of for a a we may even that the may be as of the or ideas may as be but they are by the of The of a in question is the conception at by and is a between different This has been by may be as an In very on experiments with as that was as a of of and experiments to the Lamarckian view have as even these may be as all the of experiments is in quite in of But we in and that for a of the the is a The of in question is to this can not statements just as to their but accordance with conception the famous words from the be from and some very of have the for the is that we different as different in This is an essential but no in the to that view be In a very manner be for are the in the degree or of any as it different e.g., the of by and may be very as of the of the in and they a in The of the in question between the but this is not the e.g., with or even with very some of the are the between the may or may even with of as to the in the and is no as to their But that these are with the of between the to have the the of the the reactions of the may different all of or has nothing at all to do with or of of genetics to some may to has great the of in all of from to may be with different in of the to not from that be of may in one be different in e.g., the of the that of In another may or their may be of may produce and it is to that some of on the reverse is realized on In of both characterized by a degree of to produce in the the in of The are the of the in as as in the just are of just as as the of different chemical as to chemical it may be to that different chemical or of which are to be and may quite to point the of for different of and in different or in with The essential point in the matter of that a in the same manner all chemical or in as in chemical or are not to at less to do so in the same all even quite may be for the of as some are to a This is a in as in the of has the of this point for the the of as to the and are a of the and we find in current this of with and we even have with the that the of a may in in different or but that in they into one In this of the of the in a is that view has been by in this but be in the is not for an to with questions of and between the are the of and the of and is We have with some of the it is to at The of this of has an of and cases that at with the have been more on a and have quite in accordance with The of a of this of it may be that the most of the essential point in the of the personal in heredity. the same it the of as being by the of the that the personal qualities of the organism in are the of the reactions of the The of one of may have the the of for any to be even in cases where no of to as to the cases of it is not to of the in the or for their and being reactions of that may have in the be a of to the of different as as Here we meet with the questions of correlation and of can not into a discussion as to the of with its in a discussion is to be may point that cases of presumed correlation may be cases of or more characters to the even one The and even the that they are reactions of different The of and as to the are in some with of correlation and of The discussion of the for and as to may the of may be has in as to in a of the the of we an between the of and the the in manner may be able to of the the main of the a on this it may be suggested that the or of a may be more to from its the from the of the may be of any as working as to the of is the nature of these can not as a discussion be in that the is and and even have this the in their and has clearly that it may be quite to a is to or to the of a in the that can as be determined in this by is the of between the gametes a may be The facts, that a may be in some but in and that in different cases may be very that are The famous of as to the form of may be as an In the is in it is and in both cases the one has that is a of and from in one as with But from in with as in and in the with this it is as not to or is the form of for the of which the of are to be the most is the most may even be an expression for a of in the The of the by in all cases be and it is quite to that the of the in are in cases in but in as to with chemical reactions it be in that a may be the of of any as as the of any in the in question. The elaborate of of has very and the most is the most of any in question. The or in are quite the of in the it may be that for one may be elements for the of quite this be the then the of characterized by the of in the of different able to may be by a in which be any is no to that the the of into The of by of the of are a of interest in this to cases of in which and do not the it at be that some apparent are by of the for The experiments of and have to that may and be or as to the of the is no for or In inheritance we meet with of the same nature as in the of as the for the more or less of the different of in may the as has in cases the different degree of with which the of gametes is realized may the of in the as has Here we can not the in a of the a of concerning this Only one of may be viz., the to or In cases of inheritance the in question be to by the act of or, in accordance with the and the to the in some manner be In this which is very with the conception of as be of to be in the of the modern some cases in the of as to the of to be a the insight by experiments as as by concerning the of has the question in a The of and have to quite as to the of In cases no is no is in cases is no for any or of as to this has the in question. But cases of these as to the of the of are the most and most has in a and manner that the in with the be of cases to these and gained an with and was in But even this may with The for is has clearly of the concerning the of the with the of the of that of and in is a The is determined by different in the same and the of by and of these a of in be these the of the in question. we have to and we for the the which is between as and as in of no a as an and it is not to find that the of the of the be the of the so it is in the of experiments with as has clearly of heredity in concerning both and may be with in question. in that certain in for the view that we have no inheritance but true as as in the cases of as we may in the cases of may then in a more manner the true nature of the apparent in as we can that this not with be in that have been very between the in these experiments are with great and parts of the those may have can not be to it is that in may have great the and in a which into and to be into has a very the and form of the in question. Here are not the the of viz., that or characters may be determined by different and that one of may have different it that is in a very but may be even very for this the may be into But is to do in the as as to the is as the of be a with But all the of the of do not as to to the that the of and so on may be regarded as or of the and of all things in the as their This view is even in those cases where can be In the discussion as to the of true the have of a as characters of in cases where the elements of the in question are as it may be is not at all for the of But the of for is quite different from the that elements have for the of heredity. The question of as the presumed of to be an not able to any for “the of the in the The organism is in its and by its parts of the individual are as to In has been no as to this and as to has for a the same view the of and who have suggested that is determined or at any by a of the we the in the of the The of and the of parts in the individual may their the of the But these as a not or the of the in question. on we the problem of by Here we have to point the that with a more those substances or the reactions of which we of characterized by the of The of the of their to that this as as the and of in the some of the of The discussion of to the question of or In the of modern of presumed of in e.g., as to in But more analytical experiments have in cases in the the characters in question to be more reactions at has the question in a quite a working the be not of but of the gametes as a not be as the by of the of a with be of of the that this be able to “the of so with in and so or by Here we again the question of that the by and are more consistent with the real nature of the in question. the has not been able to that cases of are of but even the as to in and by as a not to any real for cases as has viz., nature being for in some may at the of being to or to different of in the in question. But a to the real of The very of as to the of certain characters in have clearly a or a in of any be in that a of are in and these concerning all and a to the of all it be suggested that in parts of the some of may or even the of which the The to be to the of by e.g., the of and of Here we the of in or with so by be a for the of the in e.g., for the nature of the of the (or for the in not be produce at are to point that may have a as to but that this question is in of the problem of or may be but the in modern genetics in the of as the we the of as an essential for the of matter in and for the or of we in of to find in the of and the of the and in be But this is not the The experiments of in a manner the of in the a degree of and in things it we may in modern genetics be of the and of that things in nature may be and the in heredity we may the in nature as as in more of the famous of and the of to the modern of and all as to point the of the in question. Here we not the it is to that the essential point is the or of of the The experiments of as to have in the most manner that the which produce the in this viz., the and of are able to act in a manner the of the and has the of in with the may in some cases be certain to be by but it is that in all is the in the of to the of which may the of of be that are from by in be with But is no for this in the between the in characters may be a of as it be is not at all with has the between the of in and in and as the in nature have all as in experiments with The chemical to may be the of and so on. The may be by more But are of very for the of The by the great of experiments as to and not personal as a of any as by and been are meaning from point of of characters gained to an of and the may the of as to may be as to the old question of this problem in the famous cases of has in a most manner been into terms by the and experiments of and This of the and has been for for the The not to a true or of heredity, but may be regarded as an for an that in its may be to be and even all may some to But as it to be the most in may then be as the of in ancestors and descendants, or, as in accordance with this heredity for those of the that find their expression in the and developed it is to this for its real but for the and of the great problem of heredity. In this the of famous as in as in has been the for the and the old in This is a in the of the of it at and to ideas of and in and a great of the of But just these qualities have the of for the analytical of modern which has in a true in

Frank Moosig, Julia U. Holle

New British Society for Rheumatology guideline for the treatment of ANCA vasculitis This article refers to BSR and BHPR guideline for the management of adults with ANCA associated vasculitis, by E. Ntatsaki et al., doi:10.1093/rheumatology/ket445, on pages 2306–09. In this issue of the journal an expert panel from the British Society for Rheumatology (BSR) presents an update of the 2007 BSR guideline for the treatment of ANCA-associated vasculitides (AAVs) [1]. It is remarkable that in recent years enough new evidence has accumulated to call for a revision of these recommendations, in particular because it is still challenging to conduct well-designed trials in these rare conditions. Many of the authors of the guideline have contributed significantly to the field. The British vasculitis scene belongs to the most active and productive groups worldwide and is a key part of the European Vasculitis Society (EUVAS). The guideline reflects the rapidly increasing evidence from controlled trials available in the past years and now includes biologicals [namely rituximab (RTX)] as a mainstay of treatment. The Rituximab versus Cyclophosphamide in ANCA-associated Vasculitis (RITUXVAS) EUVAS trial initiated by British vasculitis experts was one of the landmark studies in this context [2]. A milestone in 2013 was the approval of RTX for the treatment of AAV. This represents the first formal drug approval for AAV by the European Medicines Agency (EMA) in more than 40 years. Accordingly, questions concerning the appropriate use of RTX are among the most prominently discussed issues in this well-structured and straightforward guideline. Despite of the significant accrual of knowledge in recent years, the guideline also reflects that we still have to face a lot of uncertainty in the treatment of AAV patients. The guideline [1] refers to patients with disease consistent with the 2012 Chapel Hill Consensus Conference definitions [3] and thereby formally excludes a significant proportion of AAV patients. This underlines the urgent need for real diagnostic, not just classification, criteria. The ongoing EUVAS/ACR study for the development of diagnostic and classification criteria for primary vasculitis will probably establish such standards. Other definitions need international harmonization in order to increase the comparability of reported data. The present guideline defines remission as BVAS ≤1 and a daily prednisolone dose of ≤10 mg for at least 6 months. The 2007 European League Against Rheumatism (EULAR) recommendations on clinical trials in AAV suggest a BVAS of zero and a prednisolone dose of ≤7.5 mg/day [4]. Several other definitions have been used in different trials and observational studies. Furthermore, the 6 month criterion for remission in the new BSR guideline [1] is problematic. The guideline recommends switching to maintenance therapy after successful induction of remission, after treatment with CYC for example. Strict compliance with the above-mentioned definition could lead to a therapeutic gap of several months or prolonged use of CYC, which clearly is not the intention of the authors. This illustrates the difficulty in defining clinically and scientifically meaningful endpoints. Other uncertainties pertain to drug treatment regimens per se. Although it is generally accepted that high-dose glucocorticoids are the mainstay of treatment, there is still a notable lack of proven information on dosing, tapering or duration of therapy. The availability of RTX for induction of remission in AAV represents a major progression. Drug approval in this case was granted on the basis of randomized controlled trials—the RAVE trial [5] and the RITUXVAS trial [2]. These studies helped to establish an alternative treatment to CYC, yet a lot of important questions remain unanswered, such as who is the ideal patient for treatment with RTX and who should still be treated with CYC? There is a consensus that when considering first-line treatment, RTX may be the better choice for younger patients in order to preserve fertility, an advantage of RTX. While this is mechanistically logical, it still lacks formal proof. The guideline also states that RTX may be preferred in patients at high risk of infections [1]. When looking at the data from RAVE [5, 6] and RITUXVAS [2], no clear superior treatment for patients at high risk of infection could be determined during the relatively short observational periods. Considering the treatment of CYC-refractory patients, the overwhelming consensus among experts that RTX should be the drug of first choice is contrasted by a prominent lack of sufficient data. Another ongoing controversy outlined in the guideline [1] is the use of RTX for maintenance of remission. According to some uncontrolled retrospective data (e.g. [7]) and the as yet unpublished results from the French MAINRITSAN trial, addressing repetitive RTX administration for maintenance, moderate repeated doses of RTX (0.5–1 g) given at relatively long intervals (4–6 months) seem to be a promising future option. Apart from proving that RTX represents an option for maintenance there is hope that it may even be superior to conventional standard maintenance treatment such as AZA. Finding the optimal dose in order to maintain maximum remission rates and to reduce potential side effects is another major issue for future research. The ongoing RITAZAREM study assessing RTX administered as a 1 g dose every 4 months vs standard AZA will help to answer these questions. When looking at distinct clinical situations in AAV, in many cases the evidence level is still that of case series. This is especially true for the rarest of the rare AVV entities, e.g. eosinophilic granulomatosis with polyangiitis (EGPA). The guideline, capturing the available data, mainly refers to GPA and microscopic polyangiitis, but not EGPA. When considering the sparse data on many of the relevant topics, this guideline [1] will be a most valuable aid for clinical decisions in daily work. The generation of further evidence from clinical trials will hopefully lead to an update of the EUVAS/EULAR 2009 [8] recommendations, making standardization of the diagnostic and classification standards a worthwhile future task of the EULAR/EUVAS. Disclosure statement: The authors have declared no conflicts of interest.

G DurgaPriya, Soma Prathibha

The cloud storage offers users with infrastructure flexibility, faster deployment of applications and data, cost control, adaptation of cloud resources to real needs, improved productivity, etc. Inspite of these advantageous factors, there are several deterrents to the widespread adoption of cloud computing remain. Among them, security towards the correctness of the outsourced data and issues of privacy lead a major role. In order to avoid security risk for the outsourced data, we propose the dynamic audit services that enables integrity verification of untrusted and outsourced storages. An interactive proof system (IPS) with the zero knowledge property is introduced to provide public auditability without downloading raw data and protect privacy of the data. In the proposed system data owner stores the large number of data in cloud after e encrypting the data with private key and also send public key to third party auditor (TPA) for auditing purpose. TPA in clouds and it's maintained by CSP. An Authorized Application (AA), which holds a data owners secret key (sk) and manipulate the outsourced data and update the associated IHT stored in TPA. Finally Cloud users access the services through the AA. Our system also provides secure auditing while the data owner outsourcing the data in the cloud. And after performing auditing operations, security solutions are enhanced for the purpose of detecting malicious users with the help of Certificate Authority.

Stergios Papantonis

The main goal of this work is the design and analysis of passive components employing metamaterial structures and in particular the wire medium metamaterial. Although there has been a lot of research interest in the physics of such metamaterial structures, there are not many resources available describing the behaviour of classical components, such as waveguides and cavity resonators, that are formed by metamaterials. Therefore, the aforementioned widely used devices, are realized with the deployment of the "Fakirs bed of nails" and their performance is analyzed. Our motivation is to expand existing analytical models and their applications to commonly used passive electromagnetic components, with a view to explore potentially new applications. As a means of study analytical techniques together with numerical simulations and measurements were used. This thesis is structured in the following chapters. The first chapter is an introduction to the basic principles of electromagnetics and their use on the framework of metamaterials; as illustrations some state of the art applications are presented. The next chapter is a literature review covering the work that has been done in the area of our main research interest (i.e., the Fakir's bed of nails as a metamaterial). An overview of the mathematics describing its behaviour is given as well as applications of the proposed structure. Attention has been paid on the latest studies because they provide complete physical insight. Some results from this chapter are used later as background knowledge for the analysis of passive components. This chapter is intended to lay the foundations for the reader to continue reading the rest of this work without the need to look in the literature. Chapter three investigates the dispersion effects in parallel-plate waveguides with both plates being realized by the Fakir's bed of nails. This chapter serves as an example as to how the Fakir's bed of nails can be used to form components. An analytical solution describing the behaviour of the waveguide is presented and compared against full wave numerical simulations. Chapter four presents a theoretical study of the resonant behaviour of metallic nanorods. A clear analogy between the coupled rods and the split rings/split squares is shown. The decline in the resonant frequency as the gap decreases, previously described in terms of self-capacitance, is interpreted by surface plasmons coupled across the gap. Chapter five presents a new enabling technology for implementing tunable rectangular waveguide components and circuits with the use of 2D and 3D metamaterials; a holey metal surface and wire media, respectively. As proof of concepts, results for tunable rectangular waveguide filters are presented with the use of pin block inductive irises and capacitive posts. Furthermore, by adapting the traditional metal-pipe rectangular waveguide for tunability, regions of the solid metal walls are replaced by holey metasurfaces. Prototype tunable structures were measured for verification and good agreement is achieved between full-wave numerical simulations and measurements. Chapter six analyzes a radically new design of waveguide verification device, suitable for measuring instruments such as Vector Network Analyzers. The device is designed to enable its roperties to be changed, by known amounts, after the device has been connected to the system that requires verification. The performance of the device is based on introducing relative changes in the transmitted and reflected signals and so is insensitive to errors introduced by waveguide flange imperfections. This makes the technique, in principle, ideally suited for waveguide VNAs operating at millimeter- and submillimeter-wave frequencies where these flange errors can dominate the measurements. A verification device is designed, simulated and tested in WR-15 waveguide (50-75 GHz). The last part of this thesis presents a rigorous analysis of lossy spherical cavity resonators starting from first principles. The electromagnetic field inside the spherical cavity is expanded in normal waveguide modes and the eigenfrequencies of the cavity resonator are obtained analytically by enforcing the appropriate boundary conditions at the cavity wall. Unlike perturbation techniques, used when low losses are present, there are no inherent limitations in the presented analysis and, therefore, its applicability range is much broader. Exact analytical results, acting as a benchmark reference standard, are compared to those generated independently by two commercial full-wave simulation software packages (HFSS and COMSOL). When the wall transforms from being a perfect electrical conductor to free space, as its intrinsic conductivity decreases from infinity to zero, it is found that the eigenmode solvers with both software packages increasingly fail. With both software packages, all possible modeling strategies have been investigated and their associated limitations identified. Moreover, a plane-wave approximation model is proposed that accurately predicts the numerical simulation results.

Cedric S. Raine

The following reminiscence by Cedric Raine is the 10th autobiography in a series published in the Journal of Neuropathology and Experimental Neurology. These have been solicited from senior members of the neuropathology community who have been noted leaders and contributors to neuroscience and to the American Association of Neuropathologists (AANP) and have a historical perspective of the importance of neuropathology in diagnosis, education, and research. His is the first autobiography by a distinguished PhD member (as well as former president) of the AANP, highlighting the contributions and integral roles of basic neuroscientists in our Association. It is hoped that this series will entertain, enlighten, and present members of the AANP with a better sense of the legacy that we have inherited, as well as reintroduce our respected members as humans having interesting lives filled with adventures, joys, and sorrows, and allow them to present their lives in their own words. MNH, RAS “A man is the product of his thoughts. What he thinks he becomes.” Mahatma Gandhi Lacking a more original arresting opening, let me begin by saying that to be invited to join the list of esteemed neuropathologists featured in the Journal's Autobiography Series, following icons like Asao Hirano, Robert Terry, and Nicholas Gonatas, is both a privilege and a challenge. Never known for being conventional and sporting a background completely at odds with the standard training of most members of the American Association of Neuropathologists (AANP), I would like to take off on a different foot by thanking my colleagues in the Association for welcoming and accepting me, among the first PhDs, into the fold as an Active Member. When Mike Hart rang me a few months ago asking me to prepare a piece for the Series, my knee-jerk reaction was to decline on the grounds of juvenility and inappropriateness. Recognizing that autobiographies usually represent one's own self-chosen, self- redacted reminiscences, I was in no hurry to wax solipsistic to the readership and my colleagues. As we spoke, however, I rationalized the issue by recalling how many years had flown by since I became involved with the AANP (actually, 44) and how my own development as an investigator had paralleled and benefited from my affiliation with the Association and its mouthpiece, the Journal of Neuropathology and Experimental Neurology (JNEN). Setting feelings of uncertainty aside and with Mike still on the line, I thought, “this is the academic body that gave me the legs to stand on in neuropathology; of course, I'm qualified; I'll do it.” So, for an autobiography garnished more with anecdotes than achievements, read on. I was born in May 1940 in Eastbourne, England, to a single mother; the vivid description of WWII events from her provided me with images difficult to distinguish from actual memories. She used to talk about the Dunkirk evacuation and the dogfights overhead between Spitfires, Hurricanes, and ME 109s, with their contrails slicing the summer sky, all occurring while I was in my push-chair. Moreover, this coastline was also the planned landing site for the German invasion barges waiting to depart Belgium, but thanks to the Royal Air Force and the Valiant Few, it never came to pass. Not surprisingly, Eastbourne residents were advised to evacuate to safer havens, particularly as German bombers driven from the London Blitz fled our airspace and jettisoned unspent bombs along the coast. My mother decided to return to her parents' home in Carlisle, Cumberland, 400 miles north, 8 miles south of the Scottish border. We arrived in Carlisle in 1942, unannounced and definitely not welcome. Apparently, she had left Carlisle about 10 years earlier under a cloud and had not been heard of since. However, her odyssey had ended; her funds had run dry and she had come home. Aunt Maureen, who is 7 years older than me, answered the doorbell and found her sister who she had never seen, standing on the doorstep with “a beautiful little boy in a green woolen suit with small pink flowers across the front.” We were admitted into the house by my grandmother; my grandfather was summoned from his victory garden and there followed an unpleasant confrontation ending with my grandmother (my life's best friend and savior), taking me by the hand out of the fray saying “T am going to put this young man through university, “ and she did. Shortly thereafter, real memories began to form. There were 4 sisters in the house; 3 of them rather like the ugly sisters of Cinderella constantly battled with my mother and abused me at their convenience. I was terrified; I used to hide a lot and developed a bad stutter, which stayed with me until I came to the States in the late 1960s. My mother kept my hair long and in a pageboy style (remember Cedric of “Little Lord Fauntleroy?) and had me attend dancing classes at the age of 3 (Fig. 1). About 12 months later, the hair came off, my mother took a war-related job, and I was released to the Carlisle streets to become a grubby member of the populace. The dance class of Florence Wilkinson (rear center), Carlisle, 1943. That's me, fifth from left, front row, hands on knees. Note pageboy hairstyle. My aunt Maureen (extreme right, in front of man) delivered me to the class. It was wartime and, like many cities in the United Kingdom, Carlisle was in the thick of it. The United States had by now entered the war (thank heavens!), and being a center for about 6 railroad companies and situated on the only road south from Glasgow (the main port for traffic from North America), everything had to come through Carlisle, much to the delight of the local kids. The roadside and railway embankments became our playgrounds as convoys and trains of US and Canadian troops, lines of gray-painted trucks with long trailers carrying airplanes with folded wings, and tanks (oh, the tanks!) trundled through the cobbled streets of Carlisle. Near our street was a long lay-by where tanks would stop as crews took a break. I can still smell the hot oily fumes. We would race like mad to them and climb aboard shouting, “Any gum, chum?” Our reward was usually sticks of Wrigley's gum and/or a Hershey bar—what a delight to kids from families on severe rationing! On 1 occasion, an American soldier, noticing my dirty face, gave me a bar of perfumed soap with which I ran home to give my mother who had not seen its like for some years. The war had a toughening effect on kids: fathers were not around, we lived in a matriarchal society, and we grew up fast. My grandmother, anxious to get me out of the house, walked me down to Brook Street School just after I turned 4 and enrolled me as a 5-year-old in the infants' class. That worked fine until I was to take the 11-plus examination, a to the at the age of and the to a education, at which were My age was and I was to to take the the following I the 11-plus some and a and a on the I and began by saying that I had to the to a a I thought, but was by a about in I still from I of from Brook Street the to 8 but years at Carlisle an in the It was of a at the were and (Fig. the age of well on the of and to to become an My mother no worked and I was by my age from the My grandmother put her foot down and to her she going to I to the following to join the to be for the which I me a to I was by a in by local who I had while (as I summer from the age of to a while to a few taking off for the of the I that I had been by of to become the of What a I thought, as I my for the long home. The following I at to for a my Carlisle School was I mad for about years (Fig. but to down in my to on the which I with a my at I had a with a Maureen (my who I had in in the of where I many at the home of an aunt and with Maureen was after she left and I entered the but after I entered my her and, a gave her my much of my at I had my Maureen to me on the as I and she through to become a at in in were and with a in and a to the and in the United Kingdom, I entered the I the and of on my to be for as a out to with no but 3 I gave up and took a as a in the a house in a of Carlisle. well for me until the I and the local a man who had the many of he would be the to get as and I was with I was in the of a of with a by a he at me the I released the it and the under the On on the he and to climb His hands and he more his on the more he it but I to the is I the Carlisle arrived and took his a had been for earlier the he had the down the road from the many thereafter, would come into the asking to who up and I would them the that it. was to months in and I gave up my as a About a after I left I a who me of a for an at the in The was to and its was I had read of American that featured and on by and in the of and I was with through an who was a of the I to and an was I arrived at the and was up to the of a house, through which where I was to my (Fig. The was to with me about my and my where I had about and I with I the and was a As I left his me to my of some with at a in long after I left the I turned a into a My and training me in I was to the and of the from in and in and became in and The was for basic and was by which many members to and were his His was on and on were and members were to like in their and would stop at to his on my a to the of a of from the community to a by that a he had had for The in the of a for a while he up a series of a of of and from and was to be by my and the left for the to return the following to the the entered my the some of the and the to The the were the was and thereafter, being with the left the by to the were and the became members became of had not of a who would have the was home to a of and among was and only the for to were the I 6 years in the I grew to my on and, I a PhD to he me the to a not to a of to a of and with many my own was not and many young as a of and bad like and we the to the to be the on. it would be to most of the was a and that his was the in the the however, he a he would a for my and me the me to the and and prepare the for When began to and was I was from he be However, as I became more in and and more his me as his unpleasant its ugly he who I to and with me that I would this for my it I never his to get me but it put a on many a after 4 years of Maureen 1 that she had a as a for me to get down to my PhD It worked and I the in 3 but its was a that it be of and that I was not to from the As would have decided to take a to from in and I took the as the to the for my with my own after he I the product to the and for to a as my that I had my and the as a When entered the I to the for me to the to the for at the to and walked became a an with out the I would home and Maureen, no On the 10th I and I of his His he his and later, the was with the the that the for PhD in the United a that the me, and an my to 3 the decided for no to from my much and around, I to the of to into the more but it The the as I was the came in and me with a that I was as of that I my was a and home. Not I came in and was about to attend the a in with its and The and I was a PhD in there was more to had me on a my would to about a in On of the the after my he out different from were and at the of a I to the and was a of was on the that 1 would the of the following The effect was that my PhD me to and a few later, he my a friend with a PhD in at a of and I was to in I decided to there was a of for in the United Kingdom, which was in the of a to the and the United I at 1 to on of the of my but the academic in the and were Maureen and I decided to the United and, I an of a with Robert Terry, an known at the of in the I it. had also heard about me from my friend a who had left for 1 in my as a in the had become a of and had about the to his he was advised to Maureen and I to come to the United I for the of with for the and took them to for in the with a my with and to the for and to to We had no but to put our house on the of it for the small from the going and funds in and for our in England, we in with miles later, in after I the for at the AANP in the to It was a from who had been about to to take up a in became of Neurology at the of me, the in the and me he would take in the of the to he the following to the United Our in were particularly I was from training my and the me advised me not to up and to that was to while on the with the down to and the as I the he entered the I was and that I stop and the to I to until I was began to I to and to with and I and, from that was an of and that a of it was on the I into had the with his the of the and I have vivid memories of I took the and some of the at his much and into the and more was and began for I kept and and he kept and I and to me to I was me and out as he the get for I heard more about this but he never me years later, I this to an of young as of a talk a were I a better than for the On my in the I delivered the to for and would the at the up and into to for our to the to the and to As I left the with my I to he to the of the which he me my training in in the United was of his as of the by an on from and with members and never a in On a arrived at with a Maureen and a to in research. My in was I only We were by who delivered to his in where we his and their 3 and where we stayed for while I in at and Maureen the to an The me into to who was in to took me to the of the I have little more than with into small at I still it how much neuropathology had from that small (the foot in product have been waiting for me, was the (Fig. with in at an in Our was no more than off to attend to while his for I would run the until a the was in I would to a I would my on and would a between the and that of a on of a on which I had also worked and published in been my he left, gave me a of where I the and friend and and a who would become my for in the My first was an to out for there was an of in and out of that small Mike and of them were about to and were to their on These were for the most in the with a of to and were well and with the best the was this from Carlisle in a still the with a an and little from to get a foot on the and not to I the found an a some on and after a little more than 1 at and much the left had a for and, my first I with and of of which would The with and, my I would the just to read and more and more and many for What a from and the into my just as and I (Fig. were a series of on and the AANP in walked into the and me an for an from the of me to prepare the and Experimental and he would the a and the to that The was and 3 (my own an and to the in our the was and and, the to me to at the me up to with a in of a senior to an to a young was my as an investigator at The in thanks to and my colleagues at my was and after into the I was to and an training for and funds for 3 a and and a My was to a home with and that would be to and who would be to on their rather than and of more than years in my was that my from and I was at the on the (Fig. and background with my of with I an for a training and a to which my of will the with and of my in the Raine Note the I was most to a with and that in on and left the 3 of much to our own his of he was there was and we never I also an with and our many contributions to the of the of on as became more this would into the of the and the of in a PhD was for into my at a as were in My into was more by my up with and our on in the much a and of the and most I have known in (Fig. late the the of also in my of which was with of my of the at from its in until his in (Fig. was a and and an the of and our we a of for the first of in the and the of from Moreover, we worked and many of in the and as began to take center I up with and members of his at my own and to and into and our into the of with and was with and which in the first of to in in and the of a of to to and in As we entered the the began to for neuropathology in as of the and as and as began to and as became and more as for our and the at AANP Neuropathology at was also about to a with to in a by the of the decided to but only would with both left, a was was no our was and members became and began to to our Neuropathology became a of a the for a while but and to join the in left for and the was to who the for a few but of the and the he to in the and to run a a of its former (Fig. my own on had been to the it me to my colleagues on. I to (Fig. I a with the of and had the of a who me my from the of the to in in I was to the of with a of from for and and a of by the of we entered the with a of which to Neuropathology and and The were also in my and were in and at of the best I with in the my and with and the of to a of and the most of my years at came through my to and an of and into the of by a and with and were to between to of became a of my the the of an of through my 1 present them in list will me for the German (the 4 with (the 4 with and in a with the following also training with Mike and all the I my thanks for the and into my I their was and I from them at As for some of my I he with from his to his and in (Fig. As for Terry, in 3 of and to to up with a with some by (Fig. was in fine and I was to his the many the at were as as in on a from The of Terry, and we have my and I am left with my to my who my my and my and for years. was my first and as I a for from through the a was with me from the late until ran the of the Journal of which I in from to and it and my (Fig. to I be my and in from to the present My would I be my training a of and the standard for me were to have in About 12 months into my at and I our first on the of in to and I was it was On the I the of was a for a to which I was I and with and I at the I my to the up front and my me into an a in a I with the much to their was I with and my first in The AANP been the for my academic and (Fig. and its was usually the of my of the at I was into from the at a were for Active The was into the most being the the Association to and by I was to the for the and after about 3 years of and we in the AANP that be admitted as Active many years thereafter, was and the basic by who would have on the of I a AANP and on and/or delivered and for 1 was to be being the of and the and the for to Neuropathology I on the of from to academic I have I more to the AANP than to the of a few lines on Maureen and I were never with of our but in while as a in a for Maureen was to a young boy with who had been abused and by his She became of and, he was for she decided we a home. So, in at the age of he entered our lives our and, a of we entered to read and had and a a home and developed a beautiful he worked as an in a a at which he that for began he Maureen, and he never let his get in the of his was with for 12 years and became a and member of our however, the on in his years and his many years on up with and he in thereafter, in Maureen was as having and, as a my at became I began to my to and in until Maureen her like a but after a she in 7 months we had from to Maureen to as a grandmother in the young of and having to in a and her an Maureen lived long to but was never well to from the would have I Maureen much in to the years we were it was of her that I was to it along the road to Neuropathology (Fig. I have just the first is in the center with Mike Hart Maureen, my and Maureen in as a me to my which I and a with I am in There on my for colleagues me and images for of still and I am more to attend So, me on the do and

Andrew Mastin, Patrick Jaillet, Sang Chin

The minmax regret problem for combinatorial optimization under uncertainty\ncan be viewed as a zero-sum game played between an optimizing player and an\nadversary, where the optimizing player selects a solution and the adversary\nselects costs with the intention of maximizing the regret of the player. The\nexisting minmax regret model considers only deterministic solutions/strategies,\nand minmax regret versions of most polynomial solvable problems are NP-hard. In\nthis paper, we consider a randomized model where the optimizing player selects\na probability distribution (corresponding to a mixed strategy) over solutions\nand the adversary selects costs with knowledge of the player's distribution,\nbut not its realization. We show that under this randomized model, the minmax\nregret version of any polynomial solvable combinatorial problem becomes\npolynomial solvable. This holds true for both the interval and discrete\nscenario representations of uncertainty. Using the randomized model, we show\nnew proofs of existing approximation algorithms for the deterministic model\nbased on primal-dual approaches. Finally, we prove that minmax regret problems\nare NP-hard under general convex uncertainty.\n

Mandy M. Archibald, Alexander M. Clark

All is not well for nursing in the new world. The use of social media to share research, access information and build professional networks – although gaining in popularity – has been met mostly with a slow response from those in nursing and its research (Ferguson 2013). Twitter is used by over 550 million people, with 135,000 new users every day (Statistics Brain 2012). Approximately 11% of nurses use Twitter compared with 20% of adults – which places nurses a year behind the general population's usage (Robinson 2013). This inertia is curious, given that reputable health organizations, such as the World Health Organization, now use Twitter (Redfern 2013). Do nurses understand the potential benefits of Twitter? With mainstream popularity and increasing reliance in daily social life, Twitter can allow nurse researchers to connect directly, rapidly and cheaply with communities, disseminate information, and promote translation of research into practice and policy. It has also been found to be effective in engaging with and recruiting potentially hard-to-reach populations (O'Connor et al. 2014). This provides huge potential for methods and dissemination and broadens our understanding of change. Academic institutions now have to consider the merits of ‘virtual impact’ alongside traditional metrics of evaluation, such as publications. As Ferguson lamented in JAN: ‘it is time for the nursing profession to leverage social media’ (2013, p. 745). However, identifying this need does nothing to address how nurses can use Twitter better. Diffusion of Innovations Theory can help. Proposed by sociologist Everett Rogers in 1962, Diffusion of Innovations Theory has become a commonly applied theory for understanding how and at what rate innovations are adopted in different settings. Five characteristics of innovations influence this rate (Rogers 1962/2003): • Relative advantage: ‘…the degree to which an innovation is perceived as being better than the idea it supersedes’. (Rogers 1962/2003, p.229) The purpose of Twitter may not be apparent to nurse researchers. Is Twitter a social networking site; a venue to confer and communicate celebrity status; a networking platform; a venue to disseminate research findings; a site for recruiting participants; or all of the above? This versatility of Twitter actually reduces its perceived relative advantage because it is unclear what Twitter can and should be compared to. Most of these appraisals of Twitter occur in an evidence vacuum. While other widely used forms of media – such as textbooks, television and the internet – are not subject to a similar burden of proof, academics focused on evidence and value may well bemoan the lack of evaluation measures available for Twitter. Given the lack of previous comparable social media platforms, the added value of Twitter to busy professional lives may be unclear. Twitter can create a new world that is highly responsive to each member's needs and interests. Because only tweets (messages of 140 characters or fewer) from followers are viewed, twitter ‘feeds’ tend to reflect common themes. Hashtags can be used to categorize tweets and organize twitter feeds. Based on these tailored preferences, papers, blogs and news stories come to one's attention that would not otherwise have done so. This ability to both benefit from and contribute to tailored twitter feeds is a reciprocal advantage that is very useful. The relative advantage of innovations such as Twitter can be expressed through economic gains and social visibility. Academics can ‘tweet’ at zero cost. Other cost investments such as buying open access for publications can be leveraged through Twitter by tweeting links to online papers and web profiles. Academics may conflate social visibility with social prestige – reflecting a lingering perception of Twitter as a celebrity-oriented/pop culture social platform. However, as high-profile organizations such as the Canadian Nurses Association and leading journal editors in nursing harness Twitter, the social status draw of Twitter may gain appeal for nursing academics. Using Twitter may come to symbolize contemporary thinking and innovation. • Compatibility: ‘The degree to which an innovation is perceived as consistent with existing values, past experiences and needs of potential adopters’. (Rogers 1962/2003, p. 229). (Rogers 1962/2003, p. 240) Twitter's predecessors, particularly Facebook, also influence perceptions of Twitter. Largely a social platform, Facebook's infamous ‘status updates’ contributed to perceptions of Twitter as a social site for quick quips and celebrity updates. Although researchers may not distinguish between such forms of social media, in reality, different platforms can serve distinct purposes (Ferguson 2013). This perception of Twitter as another social media site means that it has come to be seen as being part of a ‘technology cluster’ – a ‘set of distinguishable elements of technology that are perceived by individuals as being interrelated’ (Rogers 1962/2003, p. 249). The implication of the technology cluster is the tendency for users to group otherwise distinguishable technological innovations together (e.g. Twitter, Facebook, LinkedIn) without recognizing their distinctive nature and merits. When the blurring of boundaries occurs for adopters, the potential benefits of specific platforms may not be recognized. That said, introducing innovations as part of a technology cluster may increase uptake and harness synergies between innovations. Twitter can be used with LinkedIn (a professional networking profile site) through which strategic use of a tweet can refer followers to a full professional profile. As the introduction of technologies has been sequential, beginning with email, faculty websites, LinkedIn, Facebook and many more that have preceded Twitter, the ‘added benefit’ of new social media innovations may not be recognized. It is natural to contrast the anticipated processes of Twitter to how academic dissemination has previously occurred – through longer formal academic journal articles that are read mostly by other academics. Twitter has been proposed as an alternative means to disseminate academic research; however, assuming that Twitter would be accepted readily as a supplementary form of dissemination risks committing the ‘empty vessels fallacy’ (Rogers 1962/2003, p. 256) wherein the previous knowledge and experiences of potential adopters are neglected. Compatibility with existing experiences is important and necessary for Twitter to ‘fit’ with nurse's existing knowledge related to academic dissemination. Developing links between Twitter and traditional avenues of dissemination can increase compatibility. For instance, integrating Twitter into conference activities by use of a conference hashtag, for example, may help. Indeed, Twitter's name alone could challenge many academics' values. Twitter is synonymous with chatter – the antithesis of academic discourse. Views of Twitter as a time-consuming platform not meritorious for academic career progression and promotion can further reduce its compatibility with extant values. As such, how Twitter is positioned within the nursing community, how it is incentivized as a knowledge translation tool and which of its benefits are emphasized influence its adoption. • Complexity: ‘The degree to which an innovation is perceived as relatively difficult to understand and use’ (Rogers 1962/2003, p. 257) As with any innovation, Twitter has a learning curve. New terminology (e.g. Tweet, Twittersphere, twitterites) and ostensibly mysterious abbreviations (e.g. RT, FFF, BFN, T/J etc.) abound and necessitate a ‘Twittonary (n.d)’ of key definitions (see http://twittonary.com/ for an example). This learning is complex, especially for people less familiar with technology. Generally, different generations define and use social media in different ways (Cain et al. 2010, Taylor et al. 2010, Jones & Hayter 2013). Generational divides in the use of Twitter persist, but may diminish as technological literacy increases (Cresci et al. 2010). As such, the demographic characteristics and background of researchers in nursing also influence perceptions of complexity and use. • Trialability: ‘degree to which an innovation may be experimented with on a limited basis’ (Rogers 1962/2003, p. 258) Trialability is a mixed bag for Twitter. Twitter can be experimented with easily through establishing, trying and deleting a user account. However, it takes time and effort to establish followers, identify other users to follow and both read and produce tweets regularly. Time and efforts are needed to understand the potential benefits of Twitter, but these also reduce its perceived trialability. This trialability is also constrained by preconceptions. For many academics, tweeting is a formative risk – tweets can potentially be read by many people, cannot be retracted and have been subject to high-profile legal debate and litigation in some countries. For those who have experimented with or regularly use Twitter, perceptions of such risk are diminished as tweets are only shared with and read by one's followers. Trialability is greatly enhanced by personal trials – suggesting a potential avenue for institutions looking to facilitate the uptake of Twitter by academic staff – via peer presentations on social media or hands-on ‘Twitter-sessions’ similar to library database search sessions. • Observability: ‘The degree to which the results of an innovation are visible to others’ (Rogers 1962/2003, p. 258) Twitter is a virtual innovation that requires no new hardware and an internet connection. The platform itself is less observable. Aside from the occasional tweet showcased in print, radio or television, tweets are not visible to those not on Twitter. Promoting Twitter through educational sessions and generating awareness of communities of scholars who have adopted the innovation may enhance Twitter's observability. Finally, as researchers and academic institutions alike can be outcomes-driven, finding ways to qualify the impact and effectiveness of Twitter, and to communicate and value these measures within academic research communities are important. Diffusion of Innovations Theory promotes understanding of how academics use Twitter and offers some direction for developing strategies to increase its use in academic settings. Twitter's popularity is increasing and may soon reach a critical mass, tipping the balance in favour of further adoption (Toole et al. 2012). As the time for early adoption of Twitter has passed, waiting for this critical mass is not enough. Institutions can help by emphasizing the relative advantages of Twitter, such as its low cost, possible reach and high impact potentials. Highlighting parallels between Twitter and other dissemination strategies can promote compatibility with values and experiences. To minimize complexities, promote trialability and increase observability guidelines on Twitter, researchers should benefit from guidelines (e.g. Mollett et al. 2011), Twitter training opportunities and better integration of Twitter into professional conferences and meetings. M.A. acknowledges the Canadian Child Health Clinician Scientist Program and the Women and Children's Health Research Institute.

Cándido Caballero‐Gil, Pino Caballero‐Gil, Jezabel Molina‐Gil

The practical deployment of vehicular networks is still a pending issue. In this paper we describe a new self-organized method of authentication for VANETs, which allows their widespread, fast and secure implementation. Our proposal does not involve any central certification authority because the nodes themselves certify the validity of public keys of the other nodes. On the one hand we propose an algorithm that each node must use to choose the public key certificates for its local store. On the other hand, we also describe a new node authentication method based on a cryptographic protocol including a zero-knowledge proof that each node must use to convince another node on the possession of certain secret without revealing anything about it, which allows non-encrypted communication during authentication. Thanks to the combination of the aforementioned tools, the cooperation among vehicles can be used for developing several practical applications of VANETs, such as detection and warning about abnormal traffic conditions. One of the most interesting aspects of our proposal is that it only requires existing devices such as smartphones, because the designed schemes are fully distributed and self-organized. In this work we include an analysis of both an NS-2 simulation and a real device implementation of the proposed algorithms, which enables us to extract promising conclusions and several possible improvements and open questions for further research.

Anuraj C.K

This paper introduce a dynamic audit service for integrity verification of untrusted and outsourced storages. Our audit service is constructed based on the techniques, fragment structure, random sampling, and index-hash table, supporting provable updates to outsourced data and timely anomaly detection. Constructed on interactive proof system (IPS) with the zero knowledge property, our audit service can provide public auditability without downloading raw data and protect privacy of the data. Also, our audit system can support dynamic data operations and timely anomaly detection with the help of several effective techniques, such as fragment structure, random sampling, and index-hash table (IHT). We also propose an efficient approach based on probabilistic query and periodic verification for improving the performance of audit services. A proof-ofconcept prototype is also implemented to evaluate the feasibility and viability of our proposed approaches. Our experimental results not only validate the effectiveness of our approaches, but also show that our system does not create any significant computation cost and require less extra storage for integrity verification.

G. Shams Ghahfarokhi

Risk and reliability analysis is presently being performed in almost all fields of engineering depending upon the specific field and its particular area. Probabilistic risk analysis (PRA), also called quantitative risk analysis (QRA) is a central feature of hydraulic engineering structural design. Actually, probabilistic methods, which consider resistance and load parameters as random variables, are more suitable than conventional deterministic methods to determine the safety level of a hydraulic structure. In fact, hydraulic variables involved in hydraulic structures, such as discharge, flow depth and velocity, are stochastic in nature, which maybe represented by relevant probability distributions. Therefore, the optimal design of hydraulic structures needs to be modelled by probabilistic methods. Reliability analysis methods are being adopted for use to develop risk management programs. Implementing the programs will ensure that safety is maintained to a robust and acceptable level. Any simple reliability analysis should include the following steps: The main work carried out relates to three different subjects in the general area of dam structures failure. These included the probabilistic methods work on: o Geometry of plunge pool downstream of flip bucket spillway o Evaluation of superelevation in open channel bends o Hydrodynamic loading on buildings by floods 1. Geometry of plunge pool downstream of flip bucket spillway Extreme scouring can gradually undermine the foundations of structures such as spillway and body dams and the areas downstream of dams. Extensive plunge pools downstream of flip bucket spillway structures, which are caused by jets of different configurations, form an important field of research. The plunge pool mechanism is more complex because of difficulties arising from the modelling of bed rock and sediment load flow in and around the scour hole caused by the jet effect of the flow downstream of flip bucket spillway. The experimental study of plunge pool has been limited to the consideration of variables involved in the plunge pool geometry. The reliability-based assessment of the geometry of the plunge pool downstream of a flip bucket spillway. Experimental data obtained from a model of a flip bucket spillway has been used to develop a number of equations for the prediction of scour geometry downstream from a flip bucket spillway of a large dam structure. The accuracy of the developed equations was examined both through statistical and experimental procedures with satisfactory results. 2. Evaluation of superelevation in open channel bends The so-called centrifugal force caused by flow around a curve results in a rise in the water surface at the outside wall and a depression of the surface along the inside wall. This phenomenon is called superelevation. The problems associated with flow through open channel bends deserve special attention in hydraulic engineering. Water surface slopes have been frequently reported to be a function of the curvature. But due to the difficulties in operation, the theoretical basis of superelevation has been discussed in depth in the literature. Furthermore, experience indicates that existing theory does not lead to good results at the present status. Superelevation in the Ziaran Flume (Iran) has led to severe erosion of the bank and has undermined the structure. Therefore, this study aims to cast light on the cause of overtopping by superelevation. By means of direct observation on the flume’s hydraulic performance, during full discharge, and from generalization of the field data, a more reliable prediction method of the magnitude of superelevation has become possible. The probabilistic analysis is shown to have several advantages in comparison with deterministic analysis methods. 3. Hydrodynamic loadings on buildings by floods Assessing the vulnerability of buildings in flood-prone areas is a key issue when evaluating the risk induced by flood events, particularly because of its proved direct influence on the loss of life during catastrophes. Hydrodynamic loads are caused by water flowing along, against and around a structural element or system. Hydrodynamic loads are basically of the lateral type and are related to direct impulsive loads by the moving mass of water, and to drag forces as the water flows around the obstruction. Where application of hydrodynamic loads is required, the loads shall be calculated or estimated by recognized engineering and reliable methods. A comprehensive methodology for risk assessment of buildings subjected to flooding is nevertheless still missing. A new set of experiments has been performed in this thesis with the aim of shedding more light on dynamics of flood induced loads and their effects on buildings with state of the art benchmarks. In this research, an overview is given of flood induced load on buildings, the new experimental work is then presented, together with results from preliminary analysis. Initial results suggest that use of existing prediction methods might be unsafe and that impulsive loading might be critical for both the assessment of the vulnerability of existing structures and the design of new flood-proof buildings. The research presented in this thesis is focused on developing and applying probabilistic design, safety, system reliability and risk based design in the field of hydraulic structures design in the open channel bends, plunge pool downstream of flip bucket spillway and dam break analysis. Probabilistic design approach is a powerful tool in reliability assessment of civil hydraulic engineering. Uncertainty and risk are central features of hydraulic engineering. Hydraulic design is subject to uncertainties due to the randomness of natural phenomena, data sample limitations and errors, modelling reliability and operational variability. Uncertainties can be measured in terms of the probability density function, confidence interval, or statistical moment such as standard deviation or coefficient of variation of the stochastic parameters. Outcomes from this thesis are beneficial to the design of hydraulic structures in many ways; not only minimizing cost, but also educating and providing valuable knowledge for structural operators. Probabilistic methods and reliability analysis can increase the quality and value of the achievements compared to traditional dam engineering approaches. Since the goal is to avoid the dam failures by reducing risk to almost zero with optimum cost, dam safety risk analysis has a key role in modern dam safety programs. It is hoped that illustrations provided in this thesis are applicable to other civil engineering structures of similar concerns.