This thesis analyzed the Single Social Assistance System ( SUAS ) in the municipality of Paracatu, Minas Gerais, with cut in the period 2006-2015 , with the difficulties that the municipality has found to consolidate this system, considering the co-financing of social assistance in the context of fiscal adjustment underway in the country .Therefore, the legal bases were considered that institutionalized social assistance as a public policy, as well as historical contexts and budget expenditures of the three levels of the federation, in the period studied, dedicated to an approach on the financial management of social assistance in Paracatu-MG. The need for recognition of social care as a social right and ensuring access to social assistance services for those who need it signal to a reality that tends to move away from historically constructed conceptions. Decided by the Fourth National Conference on Social Assistance 2003, the implementation of SUAS is guided by principles established by the Organic Law of Social Assistance (LOAS) , considered the National Social Assistance Policy (PNAS) and is organized by the Basic Operational Norm (NOB / SUAS). The SUAS must have the management of actions based on the political and administrative decentralization, participation and co-financing. Thus, under the co-financing, it was found that among all the entities of the federation, the states have shown little improvement in the share of funding for social assistance. O. It was also considered the debate surrounding the public fund, seeking to understand its functionality, especially in prioritizing times of economic policies, with strategies of fiscal adjustments. The results were identified that in Paracatu-MG, the main difficulties SUAS consolidation are most technical references teams are not complete; significant supply socioassitencias services by entities; lack of CRAS Volante to meet the population living in rural areas and lack of proper headquarters for the Specialized Reference Centers of Social Assistance (CRAS), Reference Center for Specialized Social Assistance (CREAS) and the Municipal Development and Social Action (SEDAS).
Michele Amoretti, Giacomo Brambilla, Francesco Medioli, Francesco Zanichelli
Location-Based Services (LBSs) build upon geographic information to provide users with location-dependent functionalities. In such a context, it is particularly important that geographic locations claimed by users are trustworthy. Centralized verification approaches proposed in the last few years are not satisfactory, as they entail a high risk to the privacy of users. In this paper, we present and evaluate a novel decentralized, infrastructure-independent proof-of-location scheme based on blockchain technology. Our scheme guarantees both location trustworthiness and user privacy preservation.
Pulmonary metastasectomy is analysed in this paper according to the rules of evidence-based medicine (EBM). Our knowledge of metastasectomy lacks several crucial factors necessary for the tenets of EBM: survival without surgery in this special group of patients; knowledge of the denominator from which the cases are selected; and the biological nature of the individual tumour. If metastasectomy were introduced today as a new treatment, it would not be accepted. Our analysis provides an alternative interpretation of 5-year survival rates of 40% after metastasectomy as being a result of selection of the patients at the benign end of the continuous spectrum of malignancies. It is therefore a statistical illusion. Given the many variables and the long-time course in many patients with or without metastasectomy, the effect of surgery can only be resolved by a randomized control two-armed trial, where the outcomes between an unoperated group (the natural history) and an operated group (the natural history modified by treatment) are compared. Absence of knowledge is readily accepted by many patients if candidly and respectfully explained and so a randomized trial is possible, appropriate and acceptable to a sufficient number of patients. To shed light on whether there is truly a survival benefit from metastasectomy, a randomized trial has been started. Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC) has so far recruited 86 randomized patients and is open internationally. It is funded for a further 5 years. Interested groups are invited to join the trial. EBM has provided a logical way of defining the âindicationâ for treatment. An âindicationâ as used in medical English is the base around which we decide to recommend treatment to patients. It can be said to be the centre of the doctor's professional duty: to identify as unequivocally as possible the indication for treatment. To decide on an indication is to influence the fate of the patient. The indication has therefore to be surrounded by stringent and quality assured rules. The ideals of EBM have been of great value to patients, but at the same time we must not forget that the evidence has to be individualized. Indications for treatment may be reached from various forms of evidence and encapsulated in clinical guidelines or, when we are less certain, consensus statements. Clinical guidelines [1] seek to make irrefutable recommendations, based on the latest and best available evidence, while consensus statements are based on opinions and are more tentative. Nevertheless, we cannot expect even the most secure evidence-based guidelines to be implemented in 100% of patients. The guidance has to be personalized according to the treating doctor's view of the best interests of the individual patient. The ideals of EBM have also been of great value to doctors who have to advise for or against treatments. This can only be done conscientiously when we are able to point to evidence. The ideals of EBM have been of value to society so that we are all spared the distress and the cost of needless treatments. The introduction of new drugs and the indications for their use are now subject to stringent rules which must be adhered to. Surgical operations should be just as carefully considered. Society should not be asked to spend its precious resources on ineffective treatments. The nation's nurses and hospitals are a shared resource; the doctors as the main drivers of costs in a health system must be responsible for their proper use. The phrase Personalized Medicine came into use, as if in opposition to EBM, but it is a false dichotomy. The tightest evidence-based guideline should be overridden for some patients. That is to say they are âpersonalisedâ. But, with respect to lung metastasectomy, there are no clinical guidelines. The European Society of Thoracic Surgeons (ESTS) Lung Metastasectomy Working Group (LMWG) considered producing guidelines but concluded â⊠the level of evidence to support current practice is too low to set firm recommendations to the members of ESTS. In the absence of a randomized controlled trial looking at the effectiveness of pulmonary metastasectomy on survival and quality of life, it is unlikely that the current practice will ever be influencedâ [2]. More recently, the Society of Thoracic Surgeons (STS) has searched and not found evidence of the kind on which âtrustworthyâ clinical guidance can be based. The result is that there are no guidelines, in Europe or the USA because there is no trustworthy evidence base [1]. The leaders of ESTS' LMWG directed readers to the PulMiCC trial proposal [3]. That was more than 5 years ago. Since then, there have been many further publications but they do not introduce new information based on better evidence. They come to the same conclusions as were reached by the early follow-up studies in the 1970s and the registry data in the 1990s. In this article, we will go back to basics and examine the sources of evidence on which we might build the indication for metastasectomy. In the very earliest days of surgery for congenital heart disease, Maurice Campbell (1891â1973) made the important decision that the large number of patients they had seen at Guy's Hospital with congenital heart disease, untreatable up to that time, should be categorized in as much detail as possible. He asked that their clinical course be meticulously recorded. Without that record, he argued, future cardiologists and surgeons would never know how the newly introduced operations had altered the ânatural historyâ. What is the equivalent ânatural historyâ of lung metastases? The 5-year survival of patients with lung metastases is commonly assumed to approach zero. Is this a realistic estimate? It was contradicted by Ă berg's finding reported in 1980 of a 5-year survival rate of 25% for unoperated patients, similar to that of contemporary patients who had lung metastasectomy [4]. The data were few (3/12) and the confident limits are wide (6â57%) but they do not include zero [5]. A realistic estimate of the natural history of the disease is an absolute requirement. For present day patients with lung metastasis, we still do not have that essential information. There are registry data that provide the natural history of patients with cancer usually divided by stage. In Tables 1 and 2, we show cancer registry data for survival of all patients with colorectal cancer and sarcoma in the worst category in the registry, designated Stage 4. This includes only patients who already had metastases at the time of diagnosis. Even with metastases at presentation (and these are the minority in clinical series) there is a non-trivial number of 5-year survivors. It is of the order of 10% for colorectal cancer in the cancer registry. Therefore, the number for whom survival can be attributed to lung metastasectomy is already well short of the 40% that is generally inferred from follow-up studies. Survival rates of 40% after lung metastasectomy are compatible with selection of the most favourable patients with no beneficial effect from metastasectomy [7, 8]. For many diseases, the cancer registry survival data have improved decade by decade and hence the difference attributable to metastasectomy will have narrowed. We hope that improved survival is a reflection of better treatments and effective operations, but there are other statistical factors which we will now consider. Colorectal cancer Five-year survival data of patients with metastases at registration. Thames Cancer Registry cases registered as having metastases from colorectal cancer at the time of diagnosis in three decades from 1980 to 2009. It is unlikely that many of these patients underwent lung metastasectomy. For example the most active group in the Thames region at the time reported 29 patients having lung metastasectomy for carcinoma of any type in an 8-year period (<4 per annum) [6]. These 5-year survival figures provide an order of magnitude for the survival of registered patients with metastases of nearly 10%. If the most favourable quartile were identified as lung metastasectomy candidates but not operated on (10/25 = 0.4), âŒ40% survival would be observed [7, 8]. The colorectal cancer patients have usually not had metastases at the time of the primary resection and have already survived longer than 2â3 years from the time of diagnosis before lung metastasectomy. The authors acknowledge Henrich MĂžller for providing the data for inclusion in these tables. Colorectal cancer Five-year survival data of patients with metastases at registration. Thames Cancer Registry cases registered as having metastases from colorectal cancer at the time of diagnosis in three decades from 1980 to 2009. It is unlikely that many of these patients underwent lung metastasectomy. For example the most active group in the Thames region at the time reported 29 patients having lung metastasectomy for carcinoma of any type in an 8-year period (<4 per annum) [6]. These 5-year survival figures provide an order of magnitude for the survival of registered patients with metastases of nearly 10%. If the most favourable quartile were identified as lung metastasectomy candidates but not operated on (10/25 = 0.4), âŒ40% survival would be observed [7, 8]. The colorectal cancer patients have usually not had metastases at the time of the primary resection and have already survived longer than 2â3 years from the time of diagnosis before lung metastasectomy. The authors acknowledge Henrich MĂžller for providing the data for inclusion in these tables. Sarcoma Five-year survival data of patients with metastases at registration. Thames Cancer Registry cases registered as having metastases from bone or soft tissue sarcoma at the time of diagnosis in two decades from 1985 to 2004. The group designated to manage sarcoma in the Thames region at the time reported 43 patients having lung metastasectomy for carcinoma of any type in an 8-year period (âŒ5% per annum) [6], so these 5-year survival figures cannot be attributed to lung metastasectomy. Long survival after lung metastasectomy may reflect selection of patients with a favourable natural history of survival [9]. The authors acknowledge Henrich MĂžller for providing the data for inclusion in these tables. Sarcoma Five-year survival data of patients with metastases at registration. Thames Cancer Registry cases registered as having metastases from bone or soft tissue sarcoma at the time of diagnosis in two decades from 1985 to 2004. The group designated to manage sarcoma in the Thames region at the time reported 43 patients having lung metastasectomy for carcinoma of any type in an 8-year period (âŒ5% per annum) [6], so these 5-year survival figures cannot be attributed to lung metastasectomy. Long survival after lung metastasectomy may reflect selection of patients with a favourable natural history of survival [9]. The authors acknowledge Henrich MĂžller for providing the data for inclusion in these tables. Detection of metastases much earlier can now be achieved by more available health care and more sensitive diagnostic tests. If the diagnosis is made 1 year earlier, the recorded survival of the patient will be 1 year longer. This is called lead time bias and it creates an illusion of improving outcomes simply because the stop watch was started sooner. With the introduction of new methods of detection, we have been able to stage patients more precisely. Some patients diagnosed as Stage I lung cancer are now classified as Stage II because we can now see previously undetectable lymphatic involvement. This is called stage migration. Similarly, better detection of mediastinal node involvement with lung metastases, and the exclusion of these patients, produces a group for metastasectomy with a better natural history. Any difference in observed survival would be due to better selection, not to the metastasectomy. With computed tomography (CT) we were able to detect lung metastases. With the addition of positron emission tomography to CT, some patients with lung metastases are now seen to have unsuspected sites of cancer elsewhere in the body. This results in more exclusions, which has the effect of narrowing down the selection of patients in whom metastasectomy is âindicatedâ. The survival results will inevitably appear to be better. Higher 5-year survival in this more highly selected group may be a consequence of selection rather than metastasectomy. There is a distinction made in EBM between âefficacyâ and âeffectivenessâ [10]. Unfortunately, the two words are more or less interchangeable in every day English but in the language of EBM, efficacy is used for interventions that can be seen âto workâ. So if a surgeon removes a solitary lung metastasis and the pathologist reports cancer-free margins, the operation has efficacy; the metastasis has been removed. Whether the operation is âeffectiveâ in achieving the desired clinical outcome, which is to improve survival, the pathologist cannot say. Even after 5 years, patients may die of their same cancer and the metastasectomy can then be seen to have been ineffective as a means of cure [11]. There have been many clinical situations where repeated observation and experience were sufficient proof for a treatment to become established [11, 12]. Surgeons do not hesitate to relieve tension pneumothorax or to retrieve an inhaled object obstructing the trachea. Rightly no one asks them for randomized controlled trial (RCT) evidence. Cataract and hip surgery, and the relief of mitral and aortic stenosis, all entered practice without RCTs. In these examples, the surgeon deals with a single, clearly evident cause of the patient's problem, which is then promptly relieved by a mechanistically rational intervention. If these principles are used to test the effectiveness of lung metastasectomy, it fails the test. There are multiple factors involved and the time scale is measured in years, so the patient's survival at any time point up to and beyond 5 years cannot unequivocally be attributed to that surgical action. It is worth noting that, for treatments that can be seen to be effective by observation alone [11], the more severe the problem, the greater is the benefit to the patient. It is for that reason we are prepared to observe a small pneumothorax or a mild degree of aortic stenosis: it is for the severe cases that we know we should intervene. This is in contrast to lung metastasectomy. Patients selected for metastasectomy are the least severely affected among a heterogeneous they have metastases, longer to their and more EBM not to the patient's survival at any time point to the lung metastasectomy, without control We must that lung metastases are the cause of Patients in whom the only of cancer is the lung metastasis have a for survival, at least in the short They are not to die time so survival data are clearly in this There is an that we must to a lung metastasis because it in may to the mediastinal and from there as we will this is not the on which the practice of metastasectomy is the results are to be better if metastasectomy is a period of It is for a surgeon to to a tumour. were seen as a The in it is to all The of the indications for metastasectomy was that there should be a solitary or very few the should have been and that the patient should have the pulmonary to and the of lung to the These were and were the of set years It was also that there should have been an of time the primary This a further period of observation after the metastasis evident to that there was no or cancer the many follow-up this was found to be on years the primary surgery in cases of sarcoma and years for colorectal cancer This that only a few of all patients with lung metastases the and paper from is an example that was as the practice established The 5-year survival rate was 40% but the data were from patients operated on between and with a very wide of cancer That is an of than patients a this paper in for it to have been and more with it being the of for surgery, have several In the of lung metastasectomy, there are two by this is the in the degree of only one patient had a metastasectomy in a period If they found patients for metastasectomy that how large was the denominator from which the patients were A is the absence of any control These to Ă berg's of patients who were but not have lung metastasectomy. He found that some of them survived 5 years without metastasectomy [4]. The in this is the Registry of Lung in The analysis of patients, meticulously and clearly that the favourable factors for survival were an the primary resection of greater than years and a solitary The authors their words They these which is These are for cancer survival of treatment rather than being of a beneficial effect of metastasectomy The authors were also in their for further In their the registry would of surgery and other to be by randomized the registry as the that the in the registry of the few patients who from operation after being to have it would to the value of the That would have provided the of the unoperated survival for patients who are similar to having metastasectomy. That is the ânatural historyâ as There is important registry in which data were to practice as as possible. surgeons data on patients of all lung metastasectomy operations in their in a The point was patients who had a metastasectomy. The to the outcomes was as a as was the survival of patients metastasectomy. this of we can that than of patients with colorectal lung metastases have metastasectomy. This is with other in which this information can be If we this level of selection knowledge of for survival, it less that follow-up studies include 40% 5-year [7, 8]. These data are from a of the of time of in a lung cancer the for providing the data to this The are on the from the to the by the time in days were and the was We have the It can be seen that to have much longer than and lung The to the would have many years to a due to the of cancer and would have been unlikely to cause the of the patient. The patient would have with the before it any are seen for lung metastases and the same might be time as a means of patients for metastasectomy was in patients operated on from to In patients, the time was found to from to more than days by these patients, had metastasectomy and Patients with of less than days years whether operated on or Patients were and the metastases after They operated on with rates of do that is of course to any to them as as possible before they The was that a of patients with who had a period of and who had metastasectomy all survived for 5 years Patients with the metastases their a that has been used before in the of lung metastasectomy These various lead to that the of survival of patients after 5 years to the metastasectomy operation is a illusion with an of If we just on the data a of follow-up studies of nearly patients that survival was if there was more than one metastasis and an of less than years. The is the same as that reached in the follow-up studies in the 1970s with by the in and with a more in Nevertheless, the surgeon authors concluded â⊠it to surgery for patients with two to is the point of the same analysis and an ever more statistical result and then it with the words to We an alternative It to not only to to operations without a realistic of benefit to patients, but it is to a that is so far at with the evidence. not the patient with metastases the in this and other metastasectomy has been to not provide What is now is that and are to be effective based on the for surgical metastasectomy. They are being as a less way of the same They are being introduced without on no more than surgical without evidence from control data There are and a result of better selection, less surgery or treatment, or for a of these 5-year survival rates of after lung metastasectomy colorectal cancer as an are now around the we become able to the more for we might see even better 5-year survival rates to That would further the in the effectiveness of metastasectomy, but it would be a statistical There is new evidence that a to the practice of metastasectomy. In the of colorectal the indication for lung metastasectomy, there is a that patients who have had primary resection should be to detect metastases as early as possible so that they can be There has been a of at detection of metastases with the to of the diagnosis with current The finding is that more not lead to improved This has been found in RCTs. It one might that earlier detection for treatment would improve That has not been the the tenets of EBM, the effectiveness of metastasectomy is one that a randomized trial to an An has the that it that the and factors are similar in It is in value only by of several RCTs. A treatment with as much as lung metastasectomy would not now be introduced into practice without RCTs. An is A of patients with lung metastases of whom in are to be 5-year based on Thames Cancer Registry data The patients are according to metastases and longer between primary surgery and metastasectomy These are They are also with longer survival after metastasectomy and are used for If of these patients are among the in the that would result in the observed 40% survival by selection Patients with three or more metastases and an of 1 year and of the are In the PulMiCC trial, may any patient whom they may but the patients between the possible and are the where there is most to be The carefully selected patient with a lung metastasis, with favourable can expect a survival, not but years, the The metastases that can be seen and are very unlikely to be the cause of the patient's If metastases are that might treatment to relieve the but in they are and to or distress the end of These should be shared with the patient. In some surgeons say they the patient hope is not medical and and by other than the many patients would be to be spared an operation that will not benefit The time of the year or two of their can be in better than surgery and Surgeons are to point that there is very low with metastasectomy. is not a of in introduced highly to of drugs to patients with of was based on Metastasectomy in low of and but surgery should only be done for a treatments because they do is not and interventions have a they up and time, and they a of we know that the of with a metastasis may be for some patients. information the nature of the disease and the of with or without a metastasis, the patient may still on an The indication then their We are not or and should be a without of the patient's is not to lung metastasectomy but to base the indications on rational the patient's and an interpretation of the evidence. information I What do Our current is based on of all the evidence that we are and if this evidence we would of
Spanish Abstract: Una de las primeras medidas planteadas para desarrollar la estrategia del âMercado Unico Digitalâ (Comunicacion de la Comision Europea de 5 de mayo de 2015) es la Propuesta de Directiva sobre determinados aspectos de los contratos de suministro de contenidos digitales de 9 de diciembre de 2015 [COM(2015) 634 final]. Ese texto afronta del dificil reto de adaptar las reglas tradicionales sobre la falta de conformidad de los bienes con el contrato de compraventa al nuevo escenario del âcontrato de suministroâ de contenidos digitales. En el presente estudio se abordan en primer lugar algunas cuestiones generales de la Propuesta de Directiva: el concepto amplio de âcontenidos digitalesâ, que incluye tambien âserviciosâ como el almacenamiento en la nube (cloud computing) o las redes sociales, la naturaleza juridica de contrato de suministro âque, con un enfoque funcional acertado, no se prejuzgaâ, la relacion de la Propuesta con otras normas europeas y la decision de incluir en su ambito de aplicacion tambien los contratos cuya contraprestacion fue no dineraria, en forma de datos; esta ultima solucion, que correctamente toma en consideracion el valor monetario de los datos, resulta demasiado restringida al incorporar el requisito de que los datos deban ser facilitado âactivamenteâ por el consumidor, lo cual es objeto de critica. En segundo lugar, en estas paginas se aborda el regimen de conformidad de los contenidos digitales con el contrato (arts. 6-9), el sistema de responsabilidad del proveedor tanto por falta de suministro o retraso como por falta de conformidad de lo suministrado (art. 10) y los remedios, acciones o formas de saneamiento aparejadas a esa responsabilidad (arts. 11-14).Este analisis trata de valorar los fundamentos y consecuencias de las reglas favorables y perjudiciales para los intereses de los consumidores y alerta sobre algunas carencias, incognitas y defectos que plantean ciertos articulos, para los que se ofrecen sugerencias de modificacion o interpretaciones que permitan una adecuada ponderacion de intereses. Asi, entre las reglas favorables a la posicion de los consumidores, se analizan y valoran positivamente las normas sobre carga de la prueba, la validez de la resolucion mediante notificacion por cualquier medio o las previsiones sobre la restitucion de las contraprestaciones tras la resolucion, en las que se presta especial cuidado a la recuperacion de los contenidos generados por el usuario. En cambio, entre las reglas que plantean mayores dudas y merecen clarificacion por efecto del enfoque de armonizacion maxima esta el saber si en caso de falta de suministro el consumidor solo dispone del derecho de resolucion inmediata (mas indemnizacion) o averiguar si se pretende que el muy limitado regimen de indemnizacion solo por dano economico al entorno digital del consumidor veta a los Estados miembros aprobar otras normas para garantizar otras indemnizaciones por otros danos. Tambien se defiende que los fines de la Propuesta de Directiva quedarian mejor cubiertos si se estableciesen normas uniformes sobre prescripcion de las acciones, a falta de plazo de garantia legal. Finalmente, este ensayo se muestra especialmente critico con algunas decisiones que son claramente perjudiciales a unos intereses legitimos de los consumidores que cabia esperar mas protegidos en esta Propuesta (por contraste con otras): en concreto, se sostiene que la norma deberia consagrar algunos parametros legales y objetivos minimos sobre las expectativas razonables de los consumidores, sin dar una primacia practicamente absoluta a lo establecido unilateralmente por el proveedor; se aboga por extender la resolucion inmediata y no solo subsidiaria a las faltas de conformidad mas graves que frustran totalmente el fin del contrato para el consumidor y se realiza una interpretacion del art. 12.5 que favorece cierta relajacion de los requisitos exigidos para resolver; o se propone admitir que el consumidor pueda suspender el pago del precio pendiente mientras no se produzca la puesta en conformidad.English Abstract: The Proposal for a directive on certain aspects concerning contracts for the supply of digital content of 9 December 2015 [COM(2015) 634 final] (âthe Proposalâ) is one of the first measures to put into effect the Digital Single Market Strategy as set out in the European Commissionâs Communication of 5 May 2015. The Proposal takes up the challenge of adapting the traditional rules governing lack of conformity of goods under the law of sale to the new context of contracts for the supply of digital content. This paper will deal first with some general issues arising from the Proposal: its wide definition of âdigital contentâ, which embraces also such âservicesâ as cloud computing or social networks and platforms; the legal nature of the contract of supply âwhich is not predetermined, i.e., it is properly understood functionally rather than defined conceptuallyâ; the relationship between the Proposal and other European legal rules; and the decision to include within its scope contracts where the âcounter-performanceâ provided by the consumer for the supply of digital content is in the form of data rather than money. In the authorâs view, this last decision correctly takes account of the financial value of data, but the Proposalâs drafting is too narrow as it requires an âactiveâ role on the part of the consumer providing it. Secondly, the paper will analyse the regime of conformity of the digital content with the contract (arts. 6-9), the system of liability of the provider, both in respect of any failure to supply the digital content and of any lack of conformity of the content supplied (art. 10), and the remedies provided for these kinds of contractual non-performance (arts. 11-14).The resulting analysis reveals the extent to which the Proposal promotes or prejudices the interests of consumers, and it also indicates the gaps, uncertainties and defects in the scheme which it requires. The paper suggests changes to the text of the Proposal itself and, where appropriate, the way in which the existing text should be interpreted so as to take into account all the interests at stake. Among the more consumer-friendly rules, those on burden of proof, the validity of termination by notice by any means, and restitution of âcounter-performancesâ after termination of the contract (with particular care being taken so as to allow the retrieval of digital content generated by consumers) are to be welcomed. On the other hand, the maximum harmonization which the Proposal requires poses difficult questions in relation to those rules which are in need of further clarification by the legislator, for example, whether a consumer can terminate immediately (and claim limited damages) only in the case of any failure to supply, or whether the Proposalâs intention is that the very limited rule on the right to recover economic damage to the digital environment of the consumer precludes Member States from allowing the consumer to recover damages in respect of other types of damage. Furthermore, this paper argues that the aims of the Proposal would be better achieved if it provided a set of uniform rules on prescription with a long period, in the absence of a time limitation for liability of the supplier and for the reversal of the burden of proof. It criticises some legislative decisions that are definitely detrimental to certain legitimate interests of consumers in circumstances where a comparison with other legal rules and proposals would lead one to think that they should be better protected. In particular, the Proposal should include some legislative, objective and not just subsidiary standards or criteria on the reasonable expectations of consumers, instead of giving almost full priority to what the supplier unilaterally established in the contract. Moreover, termination should be granted to consumers immediately rather than putting this remedy at a secondary level, at least for cases of gross lack of conformity which completely frustrate the purpose of the contract from the beginning; in the absence of such a legal change, an interpretation of art. 12.5 is suggested to soften the requirements necessary for termination of the contract. Finally, the consumer should be entitled to withhold payment of any outstanding part of the price until the supplier has brought the digital content into conformity with the contract.
The âfragmentationâ of international law has been a topic of discussion among international lawyers for at least the last two decades. The increase in the number of international organizations, multilateral conventions, bilateral investment treaties, as well as the growth of international courts and tribunals has led to concerns that the coherence and unity of the international legal order would be destabilized. 1 International law, a discipline that has long confronted questions regarding its very legality and legitimacy, was faced with new questions of how to ensure that the legal order would not be pulled apart by competing and overlapping regimes of international law. 2 This âanxietyâ 3 over fragmentation slowly waned, however, and the initial warnings over the potential collapse of the international legal order now seem overblown. Some accept that fragmentation is an inevitable aspect of a decentralized legal system, but argue that international law possesses the tools to manage such divergence. Others argue that the phenomenon has failed to materialize in practice, and that even if we can point to certain examples of fragmentation, these were isolated incidents rather than evidence of an overall pattern. A Farewell to Fragmentation: Reassertion and Convergence in International Law , a collected volume edited by Mads Andenas (University of Oslo) and Eirik Bjorge (University of Oxford) combines both of these arguments. The volume accepts that fragmentation is a part of a legal system, but argues that we are beginning to see a move in the opposite direction, towards âconvergenceâ in international law, steered largely by the role of the International Court of Justice (ICJ) reasserting itself at the center of the international legal order. The book seeks to support this claim by providing a multitude of examples of the ICJ as the âcentre of gravity,â exerting influence over the diverse regimes of international law. The editors set out in the Introduction that â[e]ven if fragmentation, and the fear of fragmentation, is the subject of a rich literature, there is still need for empirical study to understand the impact of fragmentation on the legal system of international lawâ (at 3). Farewell addresses this gap in the literature by providing evidence of convergence based on a thorough examination of both the ICJ and the various regimes of international law. The first part examines âthe centre,â focusing first on the ICJ. Chapters by Judge Greenwood and Judge Cançado Trindade serve to set the scene with regard to fragmentation and unity in international law, before chapters by Vera Gowlland-Debbas and Sir Nigel Rodley focus on how the ICJ has dealt with international human rights law. Philippa Webb examines the factors that influence fragmentation and convergence in international courts, and identifies three common issues: the type of court; the area of law involved; and the procedural rules and practices of the court. Webb uncovers the underlying reasons why the ICJ has played a central role in promoting convergence, but also addresses the issues the court must face if it is to embrace its integrative role (at 168â169). The first part of the book then zooms outwards to the different âregimesâ of international law, again with a particular emphasis on international human rights law. Dean Spielmann discusses the reception of ICJ case-law into the legal order of the European Court of Human Rights (ECtHR), while Magdalena Forowicz discusses some of the factors that will lead to the ECtHR taking into account international law and the jurisprudence of the ICJ in its legal reasoning. The second part of the book is a more eclectic discussion, examining the fragmentation phenomenon with regard to the sources of international law. It first looks at customary international law and jus cogens , before turning towards fragmentation and convergence with regard to treaty interpretation. By providing such rich evidence based on practice, Farewell makes an important contribution to the literature. The volume is strengthened by chapters that focus on the role of domestic courts. Veronika Fikfakâs chapter examining the links between the ICJ and domestic courts and Alexander Orakhelashviliâs chapter on state immunity in international and English law stand out in this regard. The book also examines issues that are often overlooked in the fragmentation debate. For example, Cameron Milesâ contribution uncovers how convergence and fragmentation also take place in the field of procedural law, examining the law of provisional measures, drawing from a deep well of legal research. The book is clearly structured in a way that allows the overall argument to develop. Yet the individual chapters have not been overly edited so as to lose the various voices and opinions of the contributors. Given the bookâs breadth, this review does not examine the specific claims made in the various chapters. Rather, it will seek to address the broader methodological questions and the study of fragmentation more generally. The phenomenon of the fragmentation of international law might be broader than what Farewell suggests. The Introduction sets out three forms of fragmentation. Substantive fragmentation occurs where different disciplines of international law claim to be self-contained, âautonomousâ regimes. Institutional fragmentation stems from the proliferation of courts and tribunals without any institutional hierarchy existing among them. Methodological fragmentation relates to the sources of international law, and takes place when international courts seek to deal with these sources in a special way, often justified by the specific nature of the treaty or legal regime. These three forms of fragmentation all relate to one specific aspect of fragmentation: the interpretation and application of the law. The volume addresses the problems that arise due to the fact that the international system lacks a central body to interpret the law (although the editors argue that the ICJ is well placed to play such a role). The other source of fragmentation stems from the fact that there is no central lawmaker . Given that there is no central legislative authority in the international system, international law comprises a variety of overlapping, and at times contradictory, regimes. While the proliferation of courts and tribunals may have been an initial reason for fears of fragmentation, it really stems from the dispersal of norms among different fields of international law, through the proliferation of treaties, UN Security Council resolutions, and a variety of âsoft lawâ instruments that these multiple courts have been called upon to interpret. Fragmentation was also fueled by the status of new types of actors in this system, including non-governmental organizations (NGOs), multinational corporations, as well as various types of international lawmaking bodies such as international organizations. This growth in specialized fields of law, developed and applied by a range of actors, was a byproduct of political changes, globalization, and the increasing complexity of international problems. In Farewell , fragmentation is presented as a technical issue related to the practice of courts, and the political and other factors that led to such a process are missing. By focusing predominantly on courts, the volume addresses only one aspect of the wider fragmentation debate. The volume puts forward a convergence thesis, arguing that the ICJ, as the âcenterâ of the international legal order is capable of reasserting convergence in international law. The fragmentation literature has long discussed the proper role of the ICJ in the context of fragmentation, including various proposals for the International Court to be the primus inter pares of all international courts and tribunals. 4 Yet it should be recognized that convergence is but one of the tools that have been put forward as a method of addressing the negative elements of fragmentation. There is rich debate about constitutionalization, 5 legal pluralism, 6 âregime interaction,â 7 and normative hierarchy, all of which have also been discussed as possible ways through which fragmentation might be addressed. While Farewell intends to present the empirical evidence of fragmentation and convergence, it does not situate the convergence thesis within this wider theoretical discussion. From a methodological point of view, the editors do not explain why the ICJ was chosen as the topic of the study. Why are regional human rights courts and bodies, also discussed extensively throughout the volume, viewed as âregimesâ of international law, when they could also have been viewed as nodes in a decentralized system of international law? By choosing to focus on the ICJ, it seems to be a foregone conclusion that we will see it as the center, rather than one of many âcenters of gravityâ around which convergence might take place. Just as our ancestors looked up at the stars and confidently concluded the Earth to be fixed and at the center of the universe, international lawyers might also mistakenly conclude that the International Court is the center of the international law universe. This makes it difficult to conceive of a different model, one in which all bodies exert an effect on one another and in which there is no âcenter.â It should also be questioned whether the ICJ is in the best position to act as a âcenter of gravityâ in international law. Concerns over fragmentation first stemmed from the court itself. 8 It seems natural for lawyers to focus on courts, and with the ICJ as âthe principal judicial organ of the United Nations,â 9 the court seems an obvious candidate for promoting convergence. Yet the UN Charter does not establish the ICJ as a constitutional court of the world community. It is established to resolve disputes before it. 10 While Farewell provides multiple examples of the ICJ promoting convergence in a number of fields of international law (an oft-cited example is its approach to jurisdictional immunities) this is not the courtâs central role, and in some cases it may even abandon attempts at promoting coherence in favor of effectively resolving a specific dispute. Even when presented with an opportunity to provide clarity in key areas of international law, the court at times shows reluctance to deal with certain questions or defines its function narrowly, thereby limiting its role to promote convergence. 11 The court has general jurisdiction, but it must rely on states to bring contentious and advisory proceedings before it, limiting its opportunities to play the convergence role. Given these constraints, the ICJ may not be in the best position to act as the âcenterâ of the international legal order. Farewell does not address the idea that there may be other potential âcentersâ of the international legal order besides the ICJ. While this includes other international and regional courts, convergence can also come from other sources. There are many references throughout the volume to the work of the International Law Commission (ILC). While the ILC often relies on ICJ judgments, it can also play an independent role in promoting convergence, primarily by asserting that the international legal order is indeed a system . The ILC favors rules of general application, and has thereby shown a reluctance to develop specialized rules applicable to sub-systems of international law. 12 Other possible âcentersâ of the international legal order are the United Nations and its Charter, which have also been discussed in constitutional terms. 13 Even if convergence is taking place, there are a number of factors that may drive this. Without addressing fully these other sources, the central argument of the volume, that the ICJ is an engine behind convergence, is weakened. The central narrative of Farewell is that the unity of international law was threatened by fragmentation before a shift towards the âcenterâ occurred. Fragmentation and convergence are therefore presented as diametrically opposed poles, âin a Hegelian dialectic processâ (at 1). Judicial activity of a regional, domestic or international court can therefore only be conceptualized as moving in one of two directions: towards convergence or fragmentation. This does not allow us to conceive of activity that might simultaneously fragment and constitutionalize the international legal order. A court may, for example, contribute to methodological fragmentation by interpreting a term in a way that diverges from the practice of other courts, but may do so in a way that respects the methods and sources of international law, contributing to convergence. There appears to be no common understanding across the various chapters as to what should be viewed as examples of fragmentation or convergence. For instance, examples of courts and tribunals referring to each otherâs case-law, especially the citation of ICJ judgments by regional and domestic courts, is often presented as an example of convergence. Yet this is not necessarily indicative of convergence. Courts may choose to cite these judgments selectively, only mentioning ICJ judgments where they align with the opinion of the citing court. Various judgments that could have steered it in the other direction may have been omitted. Even more troubling, courts may cite ICJ judgments simply to lend authority to their decisions, but may misinterpret them or apply them in a unique way, thus giving the appearance of convergence when fragmentation is really taking place under the surface. Some chapters rely heavily on citations of other courts as examples of convergence without assessing the real influence the cited judgments had in a given case. While such âjudicial dialogueâ is welcomed, it should not be adduced as evidence of convergence on all occasions. 14 Another example of this inconsistency is the way in which examples of fragmentation are explained away or deemed as unimportant. Sir Christopher Greenwood, for instance, argues that âthe difference of views over MFN clauses and jurisdiction is best seen as one of those issues which arise from time to time in any legal systemâ (at 54). Regarding the law of provisional measures, Cameron Miles argues, â[a]ny deviations tend to be based on the exigencies of the constitutive instrumentâ (at 268). In relation to the Sarrazin15 decision of the Committee on the Elimination of Racial Discrimination (CERD), an apparent example of fragmentation in human rights law, Mehrdad Payandeh argues that this can be explained by the âinstitutional logicâ and âstructural biasâ of the International Convention on the Elimination of All Forms of Racial Discrimination (ICERD) (at 318). Here the contributors have identified examples of potential fragmentation but have subsequently downplayed their relevance. This is not to argue that the editors and contributors chose their examples selectively. Rather it demonstrates an inherent difficulty of conceptualizing fragmentation. One might view the action of a court as an example of either convergence or fragmentation. For example, a âuniqueâ interpretation by a court might be viewed as justified as an application of Article 31(1) of the 1969 Vienna Convention on the Law of Treaties, stating that a treaty is to be interpreted in âcontext and in the light of its object and purpose.â 16 Yet one may view the very same interpretation and conclude that the court failed to apply Art. 31(2)(c), which allows recourse to â[a]ny relevant rules of international law applicable in the relations between the partiesâ. When is a court ignoring decisions of other courts and bodies in an isolated fashion, and when is it simply applying the law faithfully in a way that is consistent with the object and purpose of the treaty? Answers to these questions become dependent on whom you ask. 17 Without this methodological rigor, the study of fragmentation itself may be becoming fragmented. As much as Farewell seeks to provide empirical evidence of fragmentation or convergence, its claim that international law is a legal system and that the ICJ has played a role in ensuring the coherence and unity of that system, has a normative element. It fits within a line of scholarship that tends to present fragmentation as an overall negative phenomenon, one that should be addressed and managed through legal techniques. It tends to assume that a move towards greater convergence is a desirable aim in international law, but this normative claim is never fully elaborated upon. Consistency and coherence are not in themselves desirable objectives. The volume tends to overlook arguments that the international legal order might be strengthened and preserved by the development of âregimes.â While they might contribute to fragmentation, such courts can also be seen as moving the law forward. Special regimes of international law, rather than undermining the unity of the legal order, may allow instead for more specialized and adapted rules that are more likely to be complied with and easier to enforce. Rather than having any international court âat the center,â there are benefits of having multiple interacting courts, borrowing from one another, competing with each other, never placing the responsibility for the coherence of the legal order in the hands of one judicial body. Farewell examines the process of convergence in a serious and systematic way, grounding its conceptual arguments in the empirical work of international and regional courts. The book provides what is clearly missing in the fragmentation debate, that is, empirical evidence from the practice of courts and tribunals demonstrating the processes through which fragmentation and convergence occur. Farewell also succeeds in doing something that few multi-contributor volumes in law are able to achieve, that is, to construct a clear argument that runs throughout the entire book. The editors advanced a hypothesis and structured the chapters in such a way so as to allow for this argument to be developed through the course of the volume. Each chapter can be read as a standalone contribution, yet the book should be read as a monograph in order to view the development of the argument. The volume strikes the balance between presenting a logical and well-structured thesis while also retaining the individual voices. There are clear benefits to this book being written in this way, rather than a single-authored monograph. The book is strengthened by the fact that it brings together established scholars and practitioners with new voices who come with specialized expertise. These different voices do not always sing to the same tune, however. Sometimes they overlap, sometimes they contradict one another, and sometimes they seem to go off on a tangent. Yet Farewell benefits from this diversity of themes, methods, approaches, and styles.
Smooth (or universal) projective hash functions were first introduced by Cramer and Shoup, at Eurocrypt'02, as a tool to construct efficient encryption schemes, indistinguishable under chosen-ciphertext attacks. Since then, they have found many other applications, including password-authenticated key exchange, oblivious transfer, blind signatures, and zero-knowledge arguments. They can be seen as implicit proofs of membership for certain languages. An important question is to characterize which languages they can handle.In this thesis, we make a step forward towards this goal, by introducing diverse modules. A diverse module is a representation of a language, as a submodule of a larger module, where a module is essentially a vector space over a ring. Any diverse module directly yields a smooth projective hash function for the corresponding language, and almost all the known smooth projective hash functions are constructed this way.Diverse modules are also valuable in their own right. Thanks to their algebraic structural properties, we show that they can be easily combined to provide new applications related to zero-knowledge notions, such as implicit zero-knowledge arguments (a lightweight alternative to non-interactive zero-knowledge arguments), and very efficient one-time simulation-sound (quasi-adaptive) non-interactive zero-knowledge arguments for linear languages over cyclic groups.
This paper examines the effects of fiscal decentralization on the education sector for a sample of 62 countries. The results suggest that different sources of fiscal decentralization have distinct effects on education expenditure and quality. While subnational governments that are financed through own-tax revenues are more likely to increase the funds allocated to education, they also seem less concerned with maintaining teaching quality. This study provides evidence that decentralized structures cater better to local social needs. Fiscal decentralization is, therefore, an important policy instrument for achieving social goals.
Shayan Eskandari, Jeremy Clark, Abdelwahab Hamou-Lhadj
In this paper we discuss existing approaches for Bitcoin payments, as suitable for a small business for small-value transactions. We develop an evaluation framework utilizing security, usability, deployability criteria,, examine several existing systems, tools. Following a requirements engineering approach, we designed, implemented a new Point of Sale (PoS) system that satisfies an optimal set of criteria within our evaluation framework. Our open source system, Aunja PoS, has been deployed in a real world cafe since October 2014.
Till Neudecker, Philipp Andelfinger, Hannes Hartenstein
Flooding Peer-to-Peer (P2P) networks form the basis of services such as the electronic currency system Bitcoin. The decentralized architecture enables robustness against failure. However, knowledge of the network's topology can allow adversaries to attack specific peers in order to, e.g., isolate certain peers or even partition the network. Knowledge of the topology might be gained by observing the flooding process, which is inherently possible in such networks,, performing a timing analysis on the observations. In this paper we present a timing analysis method that targets flooding P2P networks, show its theoretical, practical feasibility. A validation in the real-world Bitcoin network proves the possibility of inferring network links of actively participating peers with substantial precision, recall (both ~ 40%), potentially enabling attacks on the network. Additionally, we analyze the countermeasure of trickling, quantify the tradeoff between the effectiveness of the countermeasure, the expected performance penalty. The analysis shows that inappropriate parametrization can actually facilitate inference attacks.
Doxing is the intentional public release onto the Internet of personal information about an individual by a third party, often with the intent to humiliate, threaten, intimidate, or punish the identified individual. In this paper I present a conceptual analysis of the practice of doxing and how it differs from other forms of privacy violation. I distinguish between three types of doxing: deanonymizing doxing, where personal information establishing the identity of a formerly anonymous individual is released; targeting doxing, that discloses personal information that reveals specific details of an individualâs circumstances that are usually private, obscure, or obfuscated; and delegitimizing doxing, which reveals intimate personal information that damages the credibility of that individual. I also describe how doxing differs from blackmail and defamation. I argue that doxing may be justified in cases where it reveals wrongdoing (such as deception), but only if the information released is necessary to reveal that such wrongdoing has occurred and if it is in the public interest to reveal such wrongdoing. Revealing additional information, such as that which allows an individual to be targeted for harassment and intimidation, is unjustified. I illustrate my discussion with the examples of the alleged identification of the creator of Bitcoin, Satoshi Nakamoto, by Newsweek magazine, the identification of the notorious Reddit user Violentacrez by the blog Gawker, and the harassment of game developer Zoe Quinn in the âGamerGateâ Internet campaign.
Abstrac : In order to implement regional autonomy based on Law No. 22 of 1999, that the granting of autonomy to the local city / county is based on the principle of decentralization in the form of autonomy, real, and responsible. Granting authority on the basis of the principle of decentralization, causing all fields are left to local governments in the implementation of an autonomous basically become the authority and responsibility of local city and county governments fully, both concerning the determination of policy, planning, implementation, monitoring, control, and evaluation. This study aimed to describe the factors that affect the implementation of regional autonomy and decen-tralization in the provision of recommendations for the implementation of decentralization in au-tonomy. The results showed that there are four variables that can explain the performance of the implementation of decentralization in the regional autonomy in the city / county, namely managerial aspects, aspects of Human Resources organization, aspects of bureaucratic culture, and ethics of public service. Keyword: decentralization, regional autonomy
This thesis discusses how the Brazilian federalism promoted, from 1997 to 2014, initiatives to develop state capacity in municipalities. This theme was taken up on the federal agenda in the first government of Fernando Henrique Cardoso (1995-1998), continued during the two terms Lula (2003-2010), and finally, in the initial mandate of Dilma Rousseff (2011-2014). The decentralization of policies started in 1988 constitutes the political and institutional context which demands to modernize its management. It's presented how evolved the managerial and administrative qualification in the cities to situate the challenges of Brazilian cooperative federalism to support these level of government. This research was organized in three theoretical dimensions and analyzed five cases. The first dimension deals with the cooperation through territorial cooperative arrangements, regarding the Federal Joint Commitee (CAF), installed in 2003, as the object of analysis because brought together representatives from federal government and from municipalist associations. One of its fields of action was the developing of municipal state capacity. The second dimension addresses the federative cooperation by means of policy systems. It was compared the Unified Social Assistance System (SUAS), created in 2005, with the education policy, that is devoid of such systemic intergovernmental arrangement. In the education the analysis rests with Articulated Action Plan (PAR), instituted in 2007. The SUAS has a wide legislation and normatization aimed for municipal entities in which highlight demands to modernize the local bodies responsible for this policy. The goal is to compare if policy systems are more effective to promote state capacity than other kinds of federative relations. The third theoretical dimension concerns to federal programs generated to support the qualification in municipalities.The goal is to compare if policy systems are more effective to promote state capacity than other kinds of federative relations. The third theoretical dimension concerns to federal programs generated to support the qualification in municipalities. Were selected two programs: the Program of Management Modernization and Tax Administration and the Management of Basic Social Sectors (PMAT), administered by the BNDES since 1997, and the National Program of Support to the Administrative Modernization and Fiscal of Brazilian Municipalities (PNAFM), managed by the Ministry of Finance and the Federal Saving Bank (Caixa EconĂŽmica Federal) since 2001. The analysis in the three dimensions shows that, considering the comparative experience in international level, and the literature about federalism and intergovernamental relations, before the manner how were organized the territorial cooperation and the implementation of federal programs in Brazil, both modalities are not viable routes to further the modernization in municipalities. The research concludes that a national and articulated policy system, both for theoretical and empirical reasons, is the most appropriated type of federative cooperative institutionality to promote state capacity in the municipalities in realities such as Brazil. In this line, in the final of the Tesis it's proposed a analytical model that considers articulated policy systems as the most adequate model to deals with this federative challenge in a setting featured by the decentralization of policies, but that at the same time lives with a great heterogeneity and inequality of state capacity among local governments.
Permisionless decentralized ledgers ("blockchains") such as the one underlying the cryptocurrency Bitcoin allow anonymous participants to maintain the ledger, while avoiding control or "censorship" by any single entity. In contrast, permissioned decentralized ledgers exploit real-world trust and accountability, allowing only explicitly authorized parties to maintain the ledger. Permissioned ledgers support more flexible governance and a wider choice of consensus mechanisms. Both kinds of decentralized ledgers may be susceptible to manipulation by participants who favor some transactions over others. The real-world accountability underlying permissioned ledgers provides an opportunity to impose fairness constraints that can be enforced by penalizing violators after-the- fact. To date, however, this opportunity has not been fully exploited, unnecessarily leaving participants latitude to manipulate outcomes undetectably. This paper draws attention to this issue, and proposes design principles to make such manipulation more difficult, as well as specific mechanisms to make it easier to detect when violations occur.
In this paper, we reveal the attenuation mechanism of anchor of the commodity money from the perspective of logistics warehousing costs, and propose a novel Decayed Commodity Money (DCM) for the store of value across time and space. Considering the logistics cost of commodity warehousing by the third financial institution such as London Metal Exchange, we can award the difference between the original and the residual value of the anchor to the financial institution. This type of currency has the characteristic of self-decaying value over time. Therefore DCM has the advantages of both the commodity money which has the function of preserving wealth and credit currency without the logistics cost. In addition, DCM can also avoid the defects that precious metal money is hoarded by market and credit currency often leads to excessive liquidity. DCM is also different from virtual currency, such as bitcoin, which does not have a corresponding commodity anchor. As a conclusion, DCM can provide a new way of storing wealth for nations, corporations and individuals effectively.
In many electric systems worldwide the penetration of Distributed Energy Resources (DER) at the distribution levels is increasing. This penetration brings in different challenges for electricity system management; however if the flexibility of those DER is well managed opportunities arise for coordination. At high voltage levels under responsibility of the system operator, trading mechanisms like contracts for ancillary services and balancing markets provide opportunities for economic efficient supply of system flexibility services. In a situation with smart metering and real-time management of distribution networks, similar arrangements could be enabled for medium- and low-voltage levels. This paper presents a review and classification of existing DER as flexibility providers and a breakdown of trading platforms for DER flexibility in electricity markets.
BACKGROUND: In 2013, around 40 % of the schools in Sweden had structured programs to prevent tobacco and alcohol debut in compulsory school. There has unfortunately been a lack of scientific evidence to support most of the prevention methods focusing on primary prevention in schools in Sweden. The aim and purpose of the present study is to evaluate the effectiveness of the Non-Governmental Organization SMART contract-signing strategy in reducing the growth of youth substance use and other problem behaviors amongst Swedish adolescents. METHODS: Students from five schools in a medium-sized Swedish municipality were surveyed in three waves from 7(th) to 9(th) grade of compulsory school. We used General Linear Model (GLM) repeated-measures ANOVA to test if the outcome measures smoking, use of snus and alcohol, drunkenness, delinquency, and bullying significantly changed different amounts over time in groups that had participated in the SMART program for long time, a short time, sporadically- or not at all. Groups were compared on demographic background variables, and outcome measures were assessed on all measurement occasions by a one-way ANOVA. The magnitude of group differences at the end of the study was estimated according to Cohen's d. RESULTS: Number of years with a contract has an effect on the levels of self-reported youth problems in 9(th) grade. We found small to medium-sized differences in measured outcomes between students who participated in the program for the longest period of time, 5 years, and who participated for the shortest time, 0-2 years. CONCLUSION: Findings suggests that the SMART program has preventive effects on adolescent substance use.
Luke Anderson, Ralph Holz, Alexander Ponomarev, Paul Rimba · 5 authors
Half a decade after Bitcoin became the first widely used cryptocurrency, blockchains are receiving considerable interest from industry and the research community. Modern blockchains feature services such as name registration and smart contracts. Some employ new forms of consensus, such as proof-of-stake instead of proof-of-work. However, these blockchains are so far relatively poorly investigated, despite the fact that they move considerable assets. In this paper, we explore three representative, modern blockchains---Ethereum, Namecoin, and Peercoin. Our focus is on the features that set them apart from the pure currency use case of Bitcoin. We investigate the blockchains' activity in terms of transactions and usage patterns, identifying some curiosities in the process. For Ethereum, we are mostly interested in the smart contract functionality it offers. We also carry out a brief analysis of issues that are introduced by negligent design of smart contracts. In the case of Namecoin, our focus is how the name registration is used and has developed over time. For Peercoin, we are interested in the use of proof-of-stake, as this consensus algorithm is poorly understood yet used to move considerable value. Finally, we relate the above to the fundamental characteristics of the underlying peer-to-peer networks. We present a crawler for Ethereum and give statistics on the network size. For Peercoin and Namecoin, we identify the relatively small size of the networks and the weak bootstrapping process.
Problem Explaining: Nowadays the financial system has been affected dramatically by the development in the era of information and communication technology. One of these phenomena, is Crypto Currency Bitcoin is the most famous among them. In the reviews of Crypto Currency and Bitcoin, we can pay special attention to the public opinion, because it can have a significant impact on the future of money. Purpose: The aim of this study is to identify the preferences of people using Bitcoin as a novel product introduced by human into the financial system. For this purpose, the important factors in choosing Bitcoin have been checked. In terms of practical purpose and collecting descriptive information, this research is survey - correlation. Design/methodology/approach: In this study the important factors in the selection of Bitcoin through the investigation of the opinions of experts and consumers, offering model by patterning the technology acceptance and innovation publication models, interviewing with experts using a questionnaire and the analysis of the model through PLS partial least square method using Version 2 SMARTPLS software. Findings: The results show that the variables of infrastructure, structural, individualistic and cultural factors through perceived value have a significant and positive impact on the intention of using people. Meanwhile cultural factor has had the largest share, but innovative, political and environmental factors havenât had any significant effect. The results of this research indicate the effective factors in the usersâ tendency to use Bitcoin. Originality/value: The main question in this research is that: Is there any significant relationship between the values perceived by the consumer from Bitcoin and the intention of using it?
In this paper we explore several contexts where an adversary has an upper hand over the defender by using special hardware in an attack. These include password processing, hard-drive protection, cryptocurrency mining, resource sharing, code obfuscation, etc. We suggest memory-hard computing as a generic paradigm, where every task is amalgamated with a certain procedure requiring intensive access to RAM both in terms of size and (very importantly) bandwidth, so that transferring the computation to GPU, FPGA, and even ASIC brings little or no cost reduction. Cryptographic schemes that run in this framework become egalitarian in the sense that both users and attackers are equal in the price-performance ratio conditions. Based on existing schemes like {Argon2} and the recent generalized-birthday proof-of-work, we suggest a generic framework and two new schemes: MTP, a memory-hard Proof-of-Work based on the memory-hard function with fast verification and short proofs. It can be also used for memory-hard time-lock puzzles. {MHE}, the concept of memory-hard encryption, which utilizes available RAM to strengthen the encryption for the low-entropy keys (allowing to bring back 6 letter passwords).