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Apr 1, 1980·American Journal of Public Health
13 cites
Evaluation of a decentralized system for chronic disease care: seven years of observation.

Stephen T. Miller, Roger Vander Zwagg, Melanie Joyner, John W. Runyan

Observations of a publicly-financed system for the medical care of a large number of persons with chronic diseases have been made over seven years. The system combines decentralized, nurse-staffed neighborhood clinics, operated by a public health department, with a central referral clinic for consultations and the management of complicated problems. After seven years in the chronic disease program 55% of 1,004 patients with diagnoses of diabetes mellitus, hypertension, and cardiac diseases were still receiving care, 19% had died, and 26% had been lost to the program. In the seventh year, the mean diastolic blood pressure in hypertensives was 84 mm Hg and the mean serum glucose in diabetics was 203 mg/dl. For the group under care, hospital days/1000/year were 74% of the rate during the year before referral to the program and out-patient visits/1000/year were approximately the same as before referral. However, two-thirds of the visits, formerly made to a public hospital, were now being made to neighborhood clinics. The system appears to be an effective method of providing medical services for persons who formerly used the public hospital as their source of outpatient care.

Open access
Primary Care and Health Outcomes
Chronic Disease Management Strategies
Health Systems, Economic Evaluations, Quality of Life
Original source
Nov 1, 1979·PubMed
0 cites
[Goal in psychiatric nursing].

Keiko Komi

<p>“Web3” is now part of our collective imaginaries, even if the specifics of what the buzzword entails remain murky and inaccessible to many. Originally coined in 2014 by Gavin Wood, co-founder of Ethereum, to describe “a decentralised internet ecosystem based on blockchain,” the term took off after the NFT boom of 2021, catalysed by the embrace of the crypto ecosystem by the likes of Silicon Valley venture capital firm Andreessen Horowitz (a16z).</p>\n<p>Like other social technologies, the swirl of narrative, attention and capital around web3 are as much part of its utility as the tools themselves. Mainstream discourses around “the web3 space”—and the blockchains, non-fungible tokens (NFTs), cryptocurrencies, decentralised web (dweb) frameworks that make it up—have been shaped by a cacophony of criticism, partiality and hype, played out over the past five years on Twitter and Discord.</p>\n<p><em>Future Art Ecosystems 3: Art x Decentralised Tech (FAE3)</em> attempts to take a long(er) view on the impact of decentralised technologies and imaginaries on the structures and processes that underpin the development of 21st-century cultural infrastructure, specifically art and advanced technologies (AxAT). The downward slope of the hype cycle towards another “crypto winter”—as well as a market correction in the wider tech industry—is a good time to take a sober view of the lessons, potentials and affordances that have been generated over these years of energetic innovation and speculative boom and bust…</p>\n

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Psychiatric care and mental health services
Child and Adolescent Health
Original source
Jun 1, 1979
3 cites
Regulated Utilities and Solar Energy: A Legal-Economic Analysis of the Major Issues Affecting the Solar Commercialization Effort

Not Given Author

The reaction of public utilities to the addition (and competitive) sources of energy supplied by solar technologies will have a significant impact on the commercialization of solar energy. Decentralized applications of solar energy need utility-produced power to back up the energy produced by solar means. The cost and availability of this power will largely determine the acceptance of solar energy. There are three legal issues surrounding the role of utilities in the solar commercialization effort: (1) the extent to which utilities may own, sell, lease, finance, or service solar devices for utility customers; (2) the degree to which solar-powered utilities may be able to compete with existing utilities; and (3) the degree to which various utility rate structures will be allowed to penalize decentralized solar users. The impact of state constitutional and statutory provisions upon these issues is examined, along with relevant federal constitutional doctrines. Finally, the statutes of the National Energy Act, many of which specifically address the above issues, are discussed.

Open access
Legal Systems and Judicial Processes
International Environmental Law and Policies
Photovoltaic Systems and Sustainability
Original source
Jan 21, 1978·BMJ
9 cites
Vitamin E in treatment of Huntington's chorea.

Aarav Kannan J, Susanne Caro

This paper presents a preliminary exploration of the design and deployment of solidarity primitives for Web3 social security, based on insights generated during Other Internet’s Web3 Work Forum held in July 2023. The paper proposes a modular framework to develop solidarity primitives addressing the three dimensions of security for DAO contributors: psychosocial stability, financial stability, and regulatory clarity. Additionally, it outlines a range of on-chain and off-chain mechanisms and improvement proposals specific to each dimension. Lastly, it discusses current challenges to implementation.\n

Open access
Genetic Neurodegenerative Diseases
Original source
Jan 1, 1978·ACM SIGOPS Operating Systems Review
13 cites
Research problems of decentralized systems with largely autonomous nodes

Jerome H. Saltzer

A currently popular systems research project is to explore the possibilities and problems for computer system organization that arise from the rapidly falling cost of computing hardware. Interconnecting fleets of mini- or micro-computers and putting intelligence in terminals and concentrators to produce so-called "distributed systems " has recently been a booming development activity. While these efforts range from ingenious to misguided, many seem to miss a most important aspect of the revolution in hardware costs: that more than any other factor, the en_ ~ cost of acquiring and operating a free-standing, complete computer system has dropped and continues to drop rapidly. Where a decade ago the capital outlay required to install a computer system ranged from $150,000 up into the millions, today the low end of that range is below $15,000 and dropping. The consequence of this particular observation for system structure comes from the next level of analysis. In most organizations, decisions to make capital acquisitions tend to be more centralized for larger capita] amounts,

Open access
Distributed systems and fault tolerance
Optimization and Search Problems
Peer-to-Peer Network Technologies
Original source
Jan 1, 1977·KeiO Associated Repository of Academic Resources (Keio University)
0 cites
Two-level planning for multi-objective systems

ă‚­ăƒšă‚żă‚« ă‚·ăƒŸă‚ș, Kiyotaka Shimizu, æž…ć­ ćż—æ°Ž

We study a two-level system having N local systems in the lower level subordinate to a central system in the higher one, such that both central and local systems have decision-making units. The central system is a coordinating agency and the local ones are semi-autonomous operating devisions. The basic principle of planning for this organization is that the central system allocates resources so as to optimize its own objective, while the local ones optimize their own objectives using the given resources. A local objective function, fn, is a function of the lower level decision variable vector x=(x1,・・・, xN) and the higher level one a=(a1,・・・, aN), where an is a resource vector allocated to the local system n. Since the functions ■ are mutually independent, the lower level composes a multi-objective system, in which the lower level decision-makers minimize a vector objective function f =(f1,・・・,fN) with respect to x in cooperation with each other. Thus, the lower level generates a set of noninferior (i.e. Pareto optimal) solutions ■(a) being parametric with respect to a. The central decision-maker, then, chooses the optimal resource allocation a⁰ and the best noninferior solution ■⁰ corresponding to a⁰ from among a set of ■(a). The above problem becomes a decentralized two-level optimization, when the local system contains only its own variables (xn, an). Several theorems and iterative algorithms for the formulated problems are obtained by use of mathematical programming techniques.

Open access
2 source records
Optimization and Variational Analysis
Resource-Constrained Project Scheduling
Educational Technology and Optimization
Original source
Jan 1, 1977·Transactions of the Society of Instrument and Control Engineers
4 cites
Decentralized Optimization Systems and Their Application to a Class of Transportation Problem

Kiyotaka Shimizu, Eitaro Aiyoshi, Tetsuo Ueno

We are concerned with a class of organizations composed of a coordinating central system and plural semi-autonomous subsystems, such that each of them has a decision-making unit. Such a problem is regarded as that of a decentralized two-level optimization. The basic principle of planning for this organization is that the central system allocates resources so as to optimize its own objective, while the subsystems optimize their own objectives using the given resources.Within this framework of decision making, we consider a transportation problem in which N transport agents transport their own commodity. Each transport agent n, n=1, 
, N, finds optimal flow patterns of the associated commodity n so that the transportation cost is minimized based on its own objective function under the arc capacity restriction imposed by the central agent. The coordinating central agent governs the transport agents through the way of allocating the arc capacity so that the optimality of whole network system is achieved. Here, the lower level problem is composed of a set of single commodity minimum cost flow problems of the transport agents, each of which can be easily solved separately by the subsystem.The decentralized optimization problem is solved in principle by a parametric approach. A feasible direction algorithm using directional derivative and application of a constraint simplex method are proposed to solve the formulated network flow problem.

Open access
Transportation and Mobility Innovations
Transportation Planning and Optimization
Optimization and Mathematical Programming
Original source
Nov 1, 1976
0 cites
Microwave-optical double resonance spectroscopy. Progress report, February 1, 1976--January 31, 1977

David W. Pratt

Zero-field and high-field optical detection of magnetic resonance (ODMR), electron paramagnetic resonance (EPR), and optical spectroscopy experiments have been performed on several systems in order to further basic knowledge of the structure, reactions, and response to radiation of atoms, molecules, and ions in their ground and/or excited electronic states. Particularly noteworthy results for the present contract year include the determination of the complete magnetic and optical properties of the lowest triplet states of 1-chloro, 1-bromo, and 1-iodonaphthalene, the development of a microscopic model for the intramolecular heavy-atom effect in the /sup 3/(..pi..,..pi..*) states of aromatic molecules, a detailed analysis of the angular dependence of the hyperfine and quadrupole structure in triplet 1-bromonaphthalene, observation of proton hyperfine structure in the hf ODMR spectra of short-lived triplet states, a definitive paper on the relative importance of spin delocalization and second-order spin-orbit coupling effects in /sup 3/(n,..pi..*) benzophenone (a phototype photochemical system), a detailed analysis of the level-anticrossing spectra of several triplet state benzophenones which exhibit hyperfine structure in the cross-relaxation region (thus permitting the determination of key magnetic parameters in the complete absence of perturbing microwave or radiofrequency fields), optical detection of ground-state NQR transitions in host crystal molecules, the observation of strong radiofrequency transitions near avoided crossing points in Zeeman energy level diagrams of photoexcited triplet states, the construction of zero-field ODMR, ODENDOR, and hf ODENDOR spectrometers, measurements of the activation parameters for ring interconversions of several free radicals containing five- and six-membered rings, and experimental proof that the triplet state of trimethylenemethane (a key reactive intermediate in organic chemistry) is the ground state.

Open access
Molecular Spectroscopy and Structure
Photochemistry and Electron Transfer Studies
Electron Spin Resonance Studies
Original source
Jan 1, 1976·The Lancet
27 cites
CLOFIBRATE-INDUCED MYOPATHY SYNDROME

K. W. Rumpf, Ruud Albers, F. Scheler

No abstract is available for this record.

Open access
Chemotherapy-related skin toxicity
Cancer Treatment and Pharmacology
Chemotherapy-induced organ toxicity mitigation
Original source
Jan 1, 1975·Warwick Research Archive Portal (University of Warwick)
0 cites
Problems in the optimal control of finite and infinite dimensional linear systems

K.T. Parker

A review of optimal control theory for linear systems with quadratic cost functions is presented. Some of the theoretical and practical limitations are discussed with special reference to distributed parameter systems. First a procedure is described for finding the optimal control by constructing a sequence of controllers that converges to the optimal; this method is valid for systems of infinite dimension provided that the operators in the state differential equation satisfy certain conditions. The proof is carried out both for the finite and infinite time interval and the connection is shown with the Riccati equation. The main problem in implementation is that one needs complete knowledge of the state at all times in order to build the optimal controller, this is almost certainly impossible for distributed parameter systems. When the state cannot be measured completely it is proved that an optimal control is realisable for time invariant finite dimensional systems.
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\nThe problems of finding this control are then investigated and computational methods discussed. If the optimal control with complete knowledge of the state cannot be implemented, a method is presented whereby one can find bounds on the possible increase in the value of the cost function arising from the use of some sub-optimal control; several examples are considered. The constrained optimal control depends on the initial state and new optimisation criteria must be put forward to deal with the case in which the initial state is unknown; the most common consist of minimising the cost that can result from the worst initial state. It is then shown how the controllers designed according to these criteria may be improved by using one's limited observation at time zero to place some constraints on the initial state. The Liapunov matrix equation plays an important part in calculating the cost of any control so reducing the computational effort in its solution is useful. It is shown how this can be done and it is of special relevance for distributed parameter systems with their states expressed as an infinite series of eigenfunctions; the results are applied to a diffusion equation example.
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\nFinally, it is shown how optimal control theory may be applied to the design of proportional-integral-derivative controllers. This is done from two standpoints and the resulting controllers are shown to be identical, though the second method of proof is valid for infinite dimensional systems. The results are then applied to a simple example and to a distributed population dynamics system. The practicality of the methods of the thesis are applied to a system with realistic parameters; recommendations are made as to the best approaches.
\n

Open access
Aerospace Engineering and Control Systems
Differential Equations and Numerical Methods
Material Science and Thermodynamics
Original source
Sep 1, 1974·The Journal of Sociology & Social Welfare
2 cites
The Interorganizational Relationships of a Public Welfare Agency

Burton Gummer

The American social welfare field is best characterized as a highly decentralized sphere of activity in which autonomous organizations define and pursue their goals in a fairly independent fashion. The complex nature of modern social problems, however, requires concerted action by a variety of organizations if effective solutions are to be developed. This conflict between the structural nature of the welfare field and the demands of the problems to be addressed has meant that social welfare planners have had to be concerned with the conditions affecting the willingness of independent organizations to engage in cooperative activities with each other. The purposes of the present paper are twofold: (1) To identify some of the major variables that affect the interorganizational activities of social welfare organizations; and (2) to describe the actual interorganizational patterns of one such organization, a county board of public assistance.

Open access
Social Work Education and Practice
Nonprofit Sector and Volunteering
Original source
Jul 31, 1974·Data Archiving and Networked Services (DANS)
3 cites
Public goods and decentralization: The duality approach in the theory of value

Petrus Hendrikus Maria Ruys

I. Economics.- 1. Introduction.- 1.1. Economic theory and economic environment.- 1.2. Private and public goods.- 1.3. The duality approach.- 1.4. Decentralized allocation mechanisms.- 2. Equilibrium in a system of economic relations.- 2.1. General equilibrium theory.- 2.2. Optimal allocations.- 2.3. An exchange economy.- 3. Production.- 3.1. Production sets and production multifunctions.- 3.2. Conditions in the production model.- 3.3. The price structure corresponding to a technology.- 3.4. Conditions in the price space.- 3.5. Preference orderings of inputs.- 3.6. Satiation for and dispensability of inputs.- 3.7. The demand- and the price-multifunction.- 4. Consumption and production of public goods.- 4.1. The consumption model.- 4.2. Private goods, public goods and externalities.- 4.3. Private goods, public goods and transaction costs.- 4.4. Social consumption and production.- 4.5. An economy with local public goods.- 5. Equilibrium in economies with private and public goods.- 5.1. The valuation representation of an economy.- 5.2. Equilibrium in an economy with public goods only.- 5.3. Equilibrium in an economy with private and public goods.- 5.4. The two-level price equilibrium.- 5.5. Financing the public sector.- 6. The organization of economic decisions.- 6.1. Allocation mechanisms.- 6.2. Centralization and decentralization.- 6.3. Procedures with a social preference ordering.- 6.4. Procedures with individual preference orderings.- 6.5. Multi-level organization.- 7. Extensions.- 7.1. Between values and resources.- 7.2. Theory of motion.- II. Mathematics.- 8. Basic mathematical notions and notations.- 8.1. Sets, relations and multifunctions.- 8.2. Continuity of multifunctions.- 8.3. Sets and algebraic operations in Rn.- 9. Sets and duality.- 9.1. Supporting hyperplanes and separating hyperplanes.- 9.2. Polar sets.- 9.3. Reflexive sets.- 9.4. Separation and intersection of sets.- 10. Multifunction and duality.- 10.1. Operations on multifunctions.- 10.2. Properties of multifunctions.- 10.3. Convex processes.- 10.4. Convex cone-interior processes.- 10.5. Convex star and convex aureole processes.- Summary.- References.

Open access
Economic theories and models
Original source
Jan 1, 1974
0 cites
Regional planning for balanced social and economic development : a Portuguese case study

J.L. Ferreira Mendes

1. Like many other countries, Portugal is facing numerous major problems related to regional unbalance and consequently to the location of economic activity. An unfortunate tendency has long been to judge an economy almost solely from the viewpoint of national production and consumption aggregats, without reference to the geographic division of economic activity.However the questions of social justice in the distributions of the fruits of economic development are as important and as different in terms of regions as in terms of social classes.Thus, at the present, increasingly attention is not being limited to the overall results of national development; the results are being accepted as satisfactory only if they concern the whole of the country, if each region is able to contribute to and participate in the national growth..On the other hand, Government activity to guide economic and social development involves not only the activity of policies and programmes but also the losely related process of formulation of goals and means and of appraisal of the results.If planning for regional development is intended to intervene realistically upon reality, it should be a continuous process in which the various units and levels of government subject the entire process to continuous review and evaluation leading to adjustment of plans, programmes and projects whenever necessary. Review and evaluation then form the transition to a new cycle of planning and decision making, moving ahead in time on the basis of a continuous stream of feedback information. At the same time, the fact is stressed that planning is actually a combination of plan formulation and plan inplementation.Institutional framework, in the modern sense of the process of achieving intended results through organizations, is a major factor at all levels - national, regional, sectoral and local. There was a time when proposals for new development pro. jects - particularly large programmes for resource development, new industries, improved education and health services - were considered only in terms of economic and technical feasibility.. After many unfortunate failures, institutional feasibility has come to be recognized as also an important dimension of planning.For evaluating the evolution of the objectives and means which have characterized Portuguese regional planning I rely in large measure on a general policy model formulated in the light of relevant theoretical and empirical considerations from economics and related social science disciplineOne of the basic attributes of this model is its distinction among three types of analytic regions: congested, potential, and backward. The advantaSe of these distinctions over the common division between "developed" and "underdeveloped" regions is that they come to grips directly with the problem of overconcentration of population and economic activity in some areas, a problem too often neglected in favour of studying the difficulties experienced by relatively underdeveloped regions.The circumstances which have given rise to the evolution of' Portuguese regional policy are compared with the assumptions of this basic model. Attention is given to the basic theoretical notions that have animated Portuguese thought concerning regional development and urban-rural integration, as well as to concrete measures which have been undertaken or which are envisaged for the future.On the basis of these considerations an effort is made to formulate a number of generalizations regarding the potential strenghts and difficulties of regional planning policy-making and a number of operationally feasible proposale are set forth for dealing with the difficulties.2. Portuguese regional planning was initiated on the basis of a deliberated attempt to deal rationally with spatial resource allocation, namely through the policy of "ordenamento do territĂłrio".In the terminology of the Third Plan, the Portuguese approach maintains that the policy of "ordenamento do territĂłrio" must find a practical compromise between regions depending on a policy of publicly induced growth and regions depending on a policy of induced public investment. On the one hand, it must give every opportunity, under conditions of lively competition, to strong regions whose potential benefits the whole of the country. On the other hand, it must seek to involve the weak regions in a process of development at first induced, then autonomous, in a manner which will enable them to participate in the current of modernization and expansion which characterizes our time.I try to show that the difficulties of Portuguese's backward regions are in large measure a result of a relative lack of benefits deriving from social investment. This is not to deny that economic investment in backward regions will produce advantages, but the effectiveness of such projects also depends on the degree to which the regions' human resources have been developed by social investment.Therefore, I stress that while there is official recognition of the needs to provide facilities for training surplus agricultural labor for employment in industry, there has not been adequate emphasis on the general problem of developing the human resources of these areas, despite the multitude of evidence concerning pronounced needs in this regard..On the other hand, a great deal has been said and written about moving industry and other economic activities to people, but policy-makers generally are more reluctant to urge the movement of people to job sources. Until now official Portuguese policy has been unable to oppose and to diminish the growth of a surprising number of rural individually-owned farms in the face of rapid technological change. This attitude, combined with inadequate social investment, has served to perpetuate the social and economic structures characteristic of backward agricultural regions of the center and the north including a surplus agricultural labor force.One of the principal arguments in favour of moving industry to backward regions, even at considerable expense in theform of subsidies or similar means, has been that the social costs involved in this type of action are less than the social costswhich would entail the uprooting of persons seeking employment in other regions as well as the increased congestion which would result in industrial agglomerations, However, the latter difficulty is now a necessary one, since migration can be channeled to intermediate or potential, rather than congested regions.On the other hand, the issue of uprooting residents of backward areas is a genuine problem since there is abundant evidence that the number of persons preferring to live in these regions is high in both absolute and relative terms.. Moreover, migration is not feasible for many persons because deficiencies in social investment in backward regions have limited the development of human resources and thus the possibility for their employment in other regions. Nevertheless, these arguments should not be used to discourage migration, since at the margin there are always persons ready and willing to migrate from backward regions.In general, it may be said that Portuguese regional policy has been facilitated by its distinction among three types of region, and that its over-all division of effort among the regions so as to induce growth in backward regions while limiting the growth of the Lisbon region and allowing for the expansion of potential regions has been substantially correct. Investment policywithin regions, however, must place relatively greater stress on social investment for backward regions. As to population policy, the new emphasis on encouraging interregional labor migration is a positive step away from the more conservative attitudes which prevailed heretofore.3. In any event, it is obvious that the value of the Portuguese regional development policy is related to the actual context in which it is to be applied. In this respect, the creation of regional organisms to participate in the formulation of regional priorities and in the regionalization of the government budget are of particular value in the elaboration of political ends and means.Unfortunately, earlier efforts in this direction were characterized by important defects. The prograps for regional action which were drawn up as planning guidelines for the various planning regions generally have been plans in name only. They have been for the most part inventories of regional conditions at a giventime. In addition, they have been deficient intipulating orders of priority and modes of finance for suggested future projects.Nevertheless, these programs have served to confront the Regional Planning Commissions with the need for horizontal consultation and coordination in regional terms as a complement to vertical planning by sectors; they have marked an initial, if not always successful, attempt to encourage cooperation among ministries and departments on common problems..Thus, in order to satisfy the objectives of regional development foregoing discussed, the need for reform of the structures - or at least changes in the institutional apparatus - become increasingly necessary. To avoid "sprinkling" of public funds it is not enough just to introduce new methods into the organizational bodies concerned; it becomes clear that something has to be done about the decision-making structures themselves. Two complementary requirements become apparent among others:- firstly, greater decentralization of decisions within the institutional apparatus and greater participation of people.- secondly, horizontal co-ordination in order to break up the vertical compartmentalizations and to create in that way the conditions for a better synthesis capable of inspiring better decisions.Just now, a new development Plan for Portugal is in preparation covering the period 1974-1979, Considering the methods of planning which have been employed in the country, one could

Open access
Regional Development and Policy
Original source
Jan 1, 1972·Apress eBooks
2 cites
Introduction

B. Balamurugan, T. Poongodi, M. R. Manu, S. Karthikeyan · 5 authors

The moving image archive of the US Agency for International Development (USAID) includes a copy of the film The Double Day (1975), cataloged in the series Moving Images Relating to International Development Programs and Activities, 1979–1991, a collection of more than eight hundred titles “created to provide information on assistance programs supported by the Agency for International Development (AID).”1 Yet, The Double Day does not, in fact, directly depict or engage with any specific development or aid initiative. Instead, the film—directed by US-based Brazilian filmmaker Helena Solberg as part of the International Women’s Film Project collective and described as “the first Latin American feminist documentary”—examines the gendered dynamics of paid and unpaid labor through the testimonies of women from Argentina, Bolivia, Venezuela, and Mexico.2 Its presence in the USAID archive is likely a consequence of its funding history, having received support from the Inter-American Foundation, a USAID-affiliated entity; the development agencies of Denmark, Norway, and Sweden; the United Nations Development Program; and US philanthropist Calvin Cafritz.3These transnational funding structures not only enabled the film’s production but also determined its archival destination, which renders legible its place within the history of international development.4 The Double Day’s institutional trajectory reflects the shifting configurations of aid, gender, and media during a historic moment when women were being repositioned at the center of what Arturo Escobar has described as development’s “regimes of visuality.”5 Especially relevant to The Double Day’s production and exhibition was the international institutional framework of Women in Development (WID). Emerging in the early 1970s and culminating in United Nations’ proclamation of 1975 as International Women’s Year, WID emphasized women’s participation in the global economy as both an index and mechanism of development. Indeed, The Double Day premiered at the World Conference of the International Women’s Year, held in Mexico City.6 Within this context, the film forms part of a broader trajectory of media use by international organizations that intensified during the 1970s—as best exemplified by Media Habitat, a collection of 236 documentary films commissioned by the United Nations to represent urban and rural development initiatives for the 1976 Habitat Conference on Human Settlements in Vancouver. As a policy-shaping initiative, Media Habitat primarily featured films from the Global South intended not only to illustrate but also to help codify standardized audiovisual markers of “underdevelopment” that determined access to the emerging global economic order and to international aid.7Framed in relation to these international institutions and their operations, The Double Day could similarly be considered “development media”—exemplifying the type of nonfiction media produced and distributed outside of the commercial film circuits whose aspects and subcategories have been variously described in scholarship as nontheatrical, useful, sponsored, institutional, industrial, educational, or nonprofessional/amateur.8 Scholars working in this area have emphasized the institutional contexts of such media’s production and exhibition infrastructures as shaping its instrumentalized effects. From a feminist perspective, such an approach is crucial to grappling with the broader question of how “gender impacts [these works’] shape, content, and trajectories.”9 Yet we also argue that, taken in isolation, the institutional and infrastructural contexts are insufficient to account for the complex relationship between media and development, potentially not only limiting our understanding of the reach and impact of development but also distorting our interpretive conclusions. For example, to categorize The Double Day as “development media” is to overlook the film’s place within Solberg’s directorial oeuvre, as well as within the histories of both transnational women’s filmmaking and radical Latin American documentary cinema to which it simultaneously belongs. Such exclusive framing is especially limiting given that women globally were disproportionately engaged in nonfiction production throughout the twentieth century—sometimes by political choice but more often due to structural exclusions from fiction filmmaking. Even in nonfiction historiography, however, institutional media has remained particularly marginal, reinforcing hierarchies that separate such works from the aesthetic and authorial frameworks through which film history has been constructed.10 This marginalization not only tends to erase women’s contributions but also presumes a “weak” or derivative authorship, rendering these films unworthy of the interpretive attention needed to apprehend their aesthetic and political complexity.11 The same dynamic is likely to structure assumptions about “development media” as well.Categorizing The Double Day exclusively within this category would further prompt us to assume top-down institutional analyses that have been characteristic of both institutional media methodologies and the scholarship on development at large. This, in turn, would risk obscuring this film’s radical Marxist approach to women’s labor as well as its concrete contribution to activism and its attendant grassroot structures. In Mexico City, The Double Day became a catalyst for feminist solidarity in practice when one of the film’s protagonists, Bolivian activist and trade unionist Domitila Barrios de Chungara, was invited to participate in the Tribune of Non-Governmental Organizations held alongside the official UN conference.12 There, Barrios de Chungara challenged Western feminist priorities by reframing the debate around labor, class, and imperialism, helping to articulate a shared Third World feminist agenda that significantly departed from the developmentalist vision of the United Nations and USAID.13 Seen through the lens of activist media, The Double Day helped forge transnational solidarity networks by enabling information exchange across the diverse voices that shaped its making—from the women featured in the film to the activists who circulated it—revealing a considerably more dynamic interplay between institutional and grassroots or contingent media practices.Moreover, the film’s Latin American context—reflected in Solberg’s formation in Brazil as the only woman in Cinema Novo, its focus on women from across the region, and its premiere and key reception in Mexico City—requires grappling with the regional specificities of the very notion of development in its multiple iterations.14 Far from being an epistemological and political framework imposed solely by the Global North, both the practices of development and the theoretical foundations of developmentalism (understood as a broad and polysemic set of discourses) were shaped through the active participation of Latin American economists.15 Within this iteration, underdevelopment, as a constitutive notion of developmentalism, became central to a distinctly critical strand, which by the late 1960s became known as the dependency theory.16 This same approach is reflected in some of the best-known Latin American radical film manifestos of the time, arising precisely from the same milieus to which Solberg belonged.17These various considerations of the film’s history illustrate the methodological challenges confronting feminist scholars seeking to assess the impact of development on media projects, theories, and practices. To disregard the developmentalist context of such works by emphasizing their political aesthetics and affects risks reproducing a romanticized narrative of heroic resistance (albeit from a feminist perspective). Yet to engage exclusively with their institutional and material infrastructures risks naturalizing developmentalism’s political and epistemological foundations at the expense of the goals and beliefs of the many women who participated in these projects. The contradictions and ambivalences that animate such histories call for feminist frameworks capable of holding both institutional complicity and radical possibility in view.This challenge resonates with ongoing debates about the politics of the archive and what Allyson Field has termed “the practice of informed speculation.”18 As she reminds us, feminist, queer, and decolonial methodologies have long taught us to “press at the limits” of the archive to “inoculate our scholarship against our evidence’s afflictions.”19 The concern that the evidence we draw on in our analysis reproduces the very structures and blind spots of the dominant ideology and therefore shapes and delimits our interpretation becomes particularly urgent when engaging the developmentalist media corpus. Informed speculation offers an alternative by inviting the experimental, creative, and speculative rewriting of history, mobilizing the archive “in a project that runs counter to the original purpose, or the imperative to preserve, or the conditions that led to erasure.”20 Yet, as Field cautions, such speculative gestures must remain grounded in a deep and “intimate familiarity with the archive” that we are working with and against. Building on this imperative, we suggest that the developmentalist archive, in particular, demands expansion and critical reconsideration in ways that unsettle the very disciplinary frameworks through which it has been studied as well as the larger institutional contexts for such knowledge production.Our focus on The Double Day in the opening of this introduction thus foregrounds the entanglements of institutional and grassroots forces, local and international contexts, structural and interpersonal relations, and creative and economic factors that have shaped not only this film but the broader ecosystem of development media projects—and their preservation—over time. Addressing such a constellation involves transgressing methodologically entrenched divisions between political economy and aesthetics, between material infrastructures and affective regimes; reckoning with divergent periodizations across film history and world economics; and situating these within the local specificities of women’s movements and international institutional programs. It also demands attentiveness to the coexistence of multiple, and sometimes competing, understandings of development—each historically, geographically, and ideologically situated.We imagine this special issue as an opening toward a critical dialogue, not only about how such an approach might be enacted in practice but also about the far-reaching ways development paradigms have shaped both our objects of study and the contours of the field itself. The decision to center institutionally sponsored films across all the essays in this issue is deliberate and enables us to highlight institutional critique as a vital methodological imperative within our analytical framework. Created within the frameworks of international organizations, state agencies, or NGOs, these films’ histories make legible the institutional logics that underwrite their production. Yet our critique does not stop at these specific entities. Rather, we argue for a broader interrogation of the political conditions and institutional infrastructures that shape media and knowledge production more generally. This includes contemporary corporations embedded in the digital platform economy, from streaming services to the rapid expansion of AI. Equally critical is a reflexive examination of academia itself, where departments of economics, political science, and centers for development have played a formative role in producing and legitimizing developmentalist theories and policy frameworks. While the humanities and arts have at times offered critical alternatives, they have also frequently mirrored and reinforced many of the same developmentalist assumptions. A feminist analysis of the nexus between development and media must therefore unsettle not only dominant archives but also the institutional and disciplinary foundations of our own scholarly practices.As scholars, we share the complex position of navigating the same tensions between institutional complicity and emancipatory aspiration as many of the media-makers whose work we study. Mirroring our subjects is also the transnational, collective mode of this special issue’s own production as it emerges from an ongoing informal working group we have sustained over several years. While relying on institutional and disciplinary affordances—such as university funding for conferences or access to academic publishing platforms—we have been working toward creating a community that exceeds, and often resists, the prevailing logics of our academic institutions. Our aim has been to create a space for shared inquiry and mutual support that pushes back against disciplinary siloing and technocratic neoliberal assessment modes of both labor and knowledge production—and this certainly extends to our experience collaborating with the journal editors throughout the publication process. Our goal has been to examine both the persistence and variability of developmentalism, understood as what Gustavo Esteva calls a “powerful but fragile semantic constellation,” as a conceptual formation that has historically inspired, legitimized, and mobilized media projects across Asia, Africa, and Latin America.21 And gendered biopolitics, from population control to gender mainstreaming, have remained integral to development policies and media practices, recurring across formats from institutional newsreels to film festivals.We share the conviction that, far beyond the history of nonfiction institutional media, development (as both a broad ideological project and a network of material and institutional practices) and developmentalism (as a set of discourses and theoretical models associated with development) have exerted a far-reaching influence on film and media cultures at large. As such, they must be treated as a major force in shaping global film and media systems and also the many ongoing assumptions behind their critical discourses. The discipline of communication studies was founded on modernization theory governed by Cold War goals of dissemination of Western liberal democracy around the world, while “an area studies framework allowed compartmentalizing Western and non-Western outcomes of technologies that were always claimed to be universal.”22 Despite critique from postcolonial and critical race studies, many of these frameworks have remained foundational for media theory.23 In historical scholarship, as we increasingly move beyond “modernity” as a dominant conceptual anchor, engaging with practices and discourses of development opens more precise analytical pathways. These film and media’s entanglements with the logics of and economic and the associated with as well as their conceptual underdevelopment, and impact in as diverse as and of media aesthetic and paradigms in film and film and funding are developmentalist assumptions to the they to underwrite the narrative and logics of and global media from the structure of the film to the cultures of argue that a examination of the historical entanglements between film and developmentalist aesthetics, modes of as well as infrastructures and critical the and that our contemporary media is a of the historical contours of development as a field of inquiry embedded within a of some of the methodologies by the featured in this special a of this complex history, to the larger at in media, development, and gender all its development a it as an of be with practices as divergent as and in In as we work on this the of the of the USAID the ideological that have the history of international the and of this on the global its a from development as a global practice and as an institutional and which over the has as a with its own media Yet or does not erase the historical impact of these the contradictions they have reflected and over the as the of development several crucial to the economic theories of development initiatives to and through the of the development an international policy framework at from the Global to the of the Global the by the political role of and the of the International the on was challenged by dependency theory and at development as global structural the neoliberal of the the Programs by the and World imposed and as conditions for and forms of assistance became known as the major markers for international development development has moving beyond economic to such as the Human Development and the Development and from international organizations such as the United Nations to a broader network of These frameworks increasingly of and liberal of and with what in many ways to various while the of the to development’s epistemological more scholarship has toward a of its and material the field has to a of and critical by and scholars, which development as a dynamic of conceptual and political to these the studies in this special issue call for sustained analysis in place of In we draw from a of and that in of of gender and to this special issue engage that and from Mexico to contemporary specific local historical of global distinctly feminist methodologies as well as attention to studies that this issue a in the global history of development on and documentary work in Mexico how early women infrastructures as of while US films an early of state and transnational on a outside the Global as the of developmentalist both the and markers of development media, its to the and Latin central grounded in archival also women’s in transnational and the methodological of archives on study of the series to a a digital media not by but by women not as but as subjects and within circuits of neoliberal and the aesthetics and of how development’s has models of to contemporary neoliberal paradigms of and analysis how digital and gender and practices, discourses on and their of these essays the of some of the historical of developmentalist as the question of the role of the state within such on a notion of economic as a and the dominant of development that the state as the for and through infrastructural projects. This understanding of development was shared across both of the as well as in the Third The United and the increasingly mobilized international in the of the modes of international at the postcolonial of policy and ideological These programs were at the expansion of their and of while with the and decolonial of The conceptual between modernization and development that the Cold in of and hierarchies of that long and As an of postcolonial their role as of international aid concern about the of Western development projects. In alternative across the Global South that to structural between and through policies of and In many they were further the global structures. In Latin for example, this approach was through organizations such as the United Nations for Latin and the both developmentalist projects and their have taken many forms historically, and they have and they have been to a of projects, and postcolonial and development has been and in ways and with frequently political While many of these alternative frameworks the embedded in dominant Western they often technocratic and assumptions. gender and gender as for the of to be shaped by This becomes particularly in the media that of development where women frequently a crucial associated with and women were as both the subjects and of their participation in the and labor often as the index of In this study of from the 1970s how women were as of this as these about women’s urban and recurring and of a within the own of and critique that official examination of archives and enables a feminist interrogation of their mobilizing a of the in the of contribution to this issue similarly the of a dynamic within as well as across ideological the of women’s and the media of the and as active in labor and as integral to the technocratic women became of as their labor remained a of and analysis and archival with attention to the specific of and It also transnational that as a and affective a nexus of and practices through which gender, media, and developmentalism one film not as a but as part of the of alongside and work a broader concern of this special media as a of developmentalist projects. The debates the World and which international such as the United Nations and a critical historical for such primarily by postcolonial and of the for the of media and communication infrastructures in as to counter Western The a between and economic how systems of media and reinforced global hierarchies of and in an agenda that supported and alternative media infrastructures across postcolonial contexts, the framework gender as an analytical This “gender in the 1970s by of the Women in Development in relation to The Double its political critique of with its broader to center women in development policy through and This was also in of media, which was shaped by its international reach and audiovisual production and and and Yet, as WID institutional it also to the and of the women’s development programs often by in These were by a of studies, and on and the to of women’s presence and through the of their economic and In this on the filmmaker this history directly by the and of for women by the WID framework during the with and agencies the of and against Women in at the of the neoliberal turn, when institutional media often the only to access and support to projects. The an by this dynamic as of the from the Global South are to engage with the developmentalist assumptions funding models that their similarly the as a in developmentalist media history by the of and centers on the Film a between of and the attention toward the and labor by and work was foundational the of and the of audiovisual aid, as both a of development projects and a critical for their the in this issue argue for a with media, gender, and developmentalism as an field of that is and shaped by feminist and methodologies and that challenge the entanglements between academic knowledge production and and technocratic development And while methodological these dynamics at the structural the of feminist in media and cinema by this the very a

Open access
51 source records
Blockchain Technology Applications and Security
Wikis in Education and Collaboration
Digital Education and Society
Original source
Oct 1, 1970·The Annals of Mathematical Statistics
76 cites
An Operator Theorem on $L_1$ Convergence to Zero with Applications to Markov Kernels

Donald Ornstein, Louis Sucheston

A recent theorem of Orey [12] (see also [1], [6], [7], [13]) asserts that if $T$ is an $L_1$ operator induced on a discrete measure space by an irreducible recurrent aperiodic Markov matrix, then the condition (C) holds: $f \epsilon L_1, \int f = 0$ implies that $T^n f$ converges to zero in $L_1$. In an attempt to determine when (C) holds for more general operators, we at first prove the following (Theorem 1.1): Let $T$ be a positive linear contraction operator on $L_1$; if $T^nf$ and $T^{n+1}f$ intersect slightly, but uniformly in $f$ in the unit sphere of $L_1$, then $T^nf - T^{n+1}f$ converges to zero in norm. (C) follows if $T$ is conservative and ergodic (Corollary 1.3). In Section 2 we derive from this a simple proof of Orey's theorem. The main result of the paper is in Section 3 and could be called a "zero-two" theorem: Let $P(x, A)$ be a Markov kernel, and assume that there is a $\sigma$-finite measure $m$ such that for each $A, m(A) = 0$ implies $P(x, A) = 0$ a.e. and $m(A) > 0$ implies $\sum^\infty_{n=0} P^{(n)}(x, A) = \infty$ a.e. Then the total variation of the measure $P^{(n)}(x, \cdot) - P^{(n+1)}(x, \cdot)$ is either a.e. 2 for all $n$ or it converges a.e. to 0 as $n \rightarrow \infty$. In Section 4 it is shown that a version of the zero-two theorem essentially contains the Jamison-Orey generalization of Orey's theorem to Harris processes. Section 1 and Section 2 of this paper do not assume any knowledge of either operator ergodic theory or probability. Some known results in ergodic theory are applied in Section 3, but the proof of the main theorem does not depend on them.

Open access
Holomorphic and Operator Theory
Random Matrices and Applications
Spectral Theory in Mathematical Physics
Original source
Apr 1, 1970·White Rose eTheses Online (University of Leeds, The University of Sheffield, University of York)
8 cites
Primitive near-rings

William Michael Lloyd Holcombe

The theory of near-rings has arisen in a variety of ways. There is a natural desire to generalise the theory of rings and skew fields by relaxing some of their defining axioms. It has also been the hope of some mathematicians that certain problems in group theory, particularly
\ninvolving permutation groups and group representations, may perhaps be clarified by developing a coherent algebraic theory of near-rings. Moreover, there is an increasing recognition by mathematicians in many branches of the subject, both pure and applied, of the ubiquity of
\nnear-ring like objects.
\n
\nThe first steps in the subject were taken by Dickson and Zassenhans with their studies of 'near-fields', and by Wielandt with his classification of an important class of abstract near-rings. Papers by Frohlich, Blackett, Betsch and Laxton developed the theory considerably. Lately authors such as Beidleman, Ramakotaiah, Tharmanatram, Maxson, Malone and Clay have all added to our knowledge.
\n
\nThe history of the subject has been strongly influenced by our knowledge of ring theory, and although this has often been beneficial it must not be overlooked that a number of important problems in near-ring theory have no real parallel in the theory of rings. It is probably best to try to preserve a balance, and not to endeavour exclusively, either to generalise theorems from ring theory irrespective
\nof their usefulness, or to ignore the theory of rings and attempt to formulate a completely independent theory. In many cases our results are generalisations of theorems from ring-theory but at certain important junctures we will explicitly use the fact that we are dealing with a near-ring which is not a ring. This is a very interesting
\ndevelopment in the subject.
\n
\nWe proceed, in the first chapter, with a review of the terms and notation that will be used in this thesis.
\n
\nWhere definitions and concepts are of a specialized or technical nature and only used in one section, it seems more sensible to postpone introducing them until a more natural point in the proceedings.
\n
\nChapter 2 gives a summary of the results on the various radicals corresponding to the Jacobson radical for associative rings. Most of these results are well known and readily available in the literature. We also consider near-rings with one, or more, of these radicals zero.
\n
\nWe defined, in Chapter 1, three different types of primitive
\nnear-ring, which are all genuine generalisations of the ring theoretic concept. Of these three, the two most important are 2-primitive and 0-primitive near-rings. In Chapter 3, we examine 2-primitive near-rings with certain natural conditions imposed on them. A theorem is obtained
\nwhich could be considered to be the equivalent result for near-rings of the theorem classifying simple, artinian rings, due originally to Wedderburn and redeveloped by Jacobson.
\n
\nChapters 4 and 5 deal with 0-primitive near-rings satisfying
\ncertain conditions. Chapter 5 is a generalisation of Chapter 4, but we felt that the mathematical techniques involved would be clearer if the special case in Chapter 4 was expounded first. In these two chapters we classify a sizeable class of 0-primitive near-rings with identity.
\nand descending chain condition on right ideals.
\n
\nSeveral types of prime near-rings have been developed in the
\nliterature. In Chapter 6 we examine these and related concepts.
\n
\nIn the theory of rings, Goldies' classification of prime and
\nsemi-prime ring with ascending chain conditions, has been of immense importance. Whether such a result could be obtained in the theory of near-rings is a matter for conjecture, at the moment. We have made a start on the problem with the construction of a class of near-rings which
\nbehave in a very similar way to Prime rings with the Goldie chain conditions. This is the content of Chapter 7. The inspiration for its came mainly from the proof of Goldies' first theorem, due to C. Procesi, which is featured in Jacobson's book. (Jacobson [1]).
\n
\nChapter 8, is an attempt to initiate the development of a theory of vector groups and near-algebras which would play an important röle-in the future theory of near-rings, in a way, perhaps, similar to the Ale vector spaces and algebras play in ring theory. This may lead, in time, to results on 2-primitive near-rings with identity and a minimal right
\nideal, for example, or a Galois theory for certain 2-primitive nearrings. For the former problem, the experience of the semi-group theorists (Hoehake [1] etc. ) may prove useful.
\n
\nFinally a note on the numbering of results and definitions etc. If a reference is made, containing only two numbers, e. g. 1.12 then this means, "item 12 of section 1 of the present chapter". If a reference reads: 3.1.12, then this means "item 12 of section 1 of Chapter 3.

Open access
Advanced Topics in Algebra
Rings, Modules, and Algebras
Original source
Jan 1, 1970·Ecology Economy and Society–the INSEE Journal
6 cites
Estimating Willingness to Pay for Wastewater Treatment in New Delhi

Vasudha Chopra, Sukanya Das

Given the increasing demand pressure on water resources coupled with supply holdups and institutional failures, fresh-water resources are increasingly susceptible to depletion and could potentially add to water stress in India. A vast demand-supply gap necessitates water conservation, including recycling measures. India has a great potential in wastewater treatment, and one of the ways to address it is decentralisation of wastewater treatment given its environmental benefits. Based on the Contingent Valuation Method (CVM), this study assesses Delhi urban households’ willingness to pay for the Operation & Maintenance (O&M) costs of a local Wastewater Treatment Plants (WWTP) that supplies residential complexes treated water for toilet-flushing. The study found that if freshwater prices rise sufficiently for consumers, they may be willing to subsidise a decentralized WWTP to cover at least their non-potable water uses. In addition, the co-provision of such public goods can become an important supplement to urban municipal finance.

Open access
Water resources management and optimization
Social and Economic Development in India
Water Governance and Infrastructure
Original source
Jan 1, 1970·International Journal of Applied Research in Management and Economics
8 cites
The Fluctuations of Bitcoin Price during the Hacks

Jiarun Hu, Qian Luo, Jiaen Zhang

Security breaches of the cryptocurrency exchanges usually cause the price fluctuation in the market. Approximately one hundred cryptocurrency thefts, including hacks and scams, has occurred since 2012 to 2018, half of which are hacks of Bitcoins. Based on the thirty Bitcoin hacks, this study portrays the general price pattern during the hack. And it illustrates the link between the size of the hack and the subsequent price change of Bitcoin. The tests reveal that the larger the volume of the hack, the stronger the price drop. However, a similar obvious relationship does not exist for the recovery of the price. The study might be the first piece of research focus on the hacks and the price pattern in a short time period.

Open access
2 source records
Blockchain Technology Applications and Security
Market Dynamics and Volatility
Complex Systems and Time Series Analysis
Original source
Jan 1, 1970·tripleC Communication Capitalism & Critique Open Access Journal for a Global Sustainable Information Society
35 cites
The (A)Political Economy of Bitcoin

Vasilis Kostakis, Chris Giotitsas

The still raging financial crisis of 2007–2008 has enabled the emergence of several alternative practices concerning the production, circulation, and use of money. This essay explores the political economy of the Bitcoin ecosystem. Specifically, we examine the context in which this digital currency is emerging as well as its nature, dynamics, advantages, and disadvantages. We conclude that Bitcoin, a truly interesting experiment, exemplifies “distributed capitalism” and should be mostly seen as a technological innovation. Rather than providing pragmatic answers and solutions to the current views on the financial crisis, Bitcoin provides some useful and timely questions about the principles and bases of the dominant political economy. A ECONOMIA POLÍTICA DO BITCOINResumoO aquecimento da crise financeira de 2007-2008 permitiu o surgimento de vĂĄrias prĂĄticas alternativas em matĂ©ria de produção, circulação e uso do dinheiro. Este ensaio explora a economia polĂ­tica do ecossistema Bitcoin. Especificamente, vamos examinar o contexto em que essa moeda digital estĂĄ emergindo, bem como a sua natureza, dinĂąmica, vantagens e desvantagens. ConcluĂ­mos que Bitcoin, uma experiĂȘncia verdadeiramente interessante, exemplifica "capitalismo distribuĂ­do" e deve ser visto principalmente como uma inovação tecnolĂłgica. Em vez de fornecer respostas e soluçÔes pragmĂĄticas para os pontos de vista atuais sobre a crise financeira, Bitcoin fornece algumas perguntas Ășteis e oportunas sobre os princĂ­pios e as bases da economia polĂ­tica dominante.

Open access
2 source records
Blockchain Technology Applications and Security
FinTech, Crowdfunding, Digital Finance
Housing, Finance, and Neoliberalism
Original source
Mar 1, 1969·Neurosurgery
8 cites
Foreword

William C. Hsiao, Alan Maynard

On behalf of the American Association of Neurological Surgeons/Congress of Neurological Surgeons Joint Section on Disorders of the Spine and Peripheral Nerves, it is my great privilege to introduce these Guidelines for the Management of Acute Cervical Spine and Spinal Cord Injuries. These guidelines represent the initial installment of a more comprehensive guidelines initiative from the Joint Section on behalf of all practicing neurosurgeons and their patients. The Section is grateful to the small working group who devoted considerable time and effort to the generation of this outstanding document. We would like to formally recognize the Joint Section on Trauma for their important collaboration on this project. The Section would also like to acknowledge and thank the parent organizations, the American Association of Neurological Surgeons and the Congress of Neurological Surgeons, for their guidance of and support for this project, most notably through the efforts of the American Association of Neurological Surgeons/ Congress of Neurological Surgeons Guidelines Committee. The Section is also deeply indebted to Michael Apuzzo and the staff of Neurosurgery for their advice and editorial assistance in preparing this document for publication. The application of Neurosurgery’ s rigorous peer-reviewed editorial process has clearly enhanced the quality, balance, and stature of this document. Perhaps most importantly, Neurosurgery has provided an extraordinary vehicle for the widespread dissemination and ultimate incorporation of these guidelines to improve the care and enhance the outcomes of patients with traumatic cervical spine and spinal cord injuries. One of the truly important functions of organized neurosurgery is the generation of evidenced-based clinical practice guidelines. Properly developed, such guidelines can answer important questions, resolve uncertainty, identify areas of deficient knowledge and opportunities for future scientific investigation, standardize treatment, and improve the quality of care and the outcomes for patients. The now widely disseminated head trauma guidelines, for example, have clearly made a difference in the outcomes of patients with severe head injury. Guidelines development is a highly structured process with rigorous methodological criteria and exacting standards. It is a time-, labor-, and resource-intensive process that has served as a significant obstacle to more widespread guidelines development throughout neurosurgery. In the past, clinical practice guidelines have been developed by publicly supported epidemiologists and methodologists who understood study design, data analysis, and the guidelines process, but not the disease. This absence of context and clinical perspective significantly limited the value and relevance of their results. Alternatively, clinician-generated guidelines often took the form of methodologically flawed consensus panels and expert opinion, also of limited value. The Joint Spine Section recognized the importance of evidence-based clinical practice guidelines and the challenges of their development. The appropriate clinical expertise, strict adherence to established methodological standards for guidelines development, and considerable resource investment for the development, dissemination, and maintenance of the guidelines documents were deemed crucial to our guidelines initiative. Cervical spine and spinal cord injury was chosen as the initial guidelines topic because of the personal, social, and economic devastation of these injuries, their complex nature, and the high level of uncertainty, as reflected in wide practice variations, as to the value and indications for many of the aspects of evaluation and treatment. The clinical practice guidelines contained in this supplement to Neurosurgery represent a remarkable effort. They address the key issues related to the evaluation and management of these complex conditions that are relevant to the treating physician. In every chapter, the pertinent issues are succinctly stated, the published data are comprehensively presented in the evidentiary tables, and the evidence is thoroughly discussed and critically evaluated throughout the text. The linkage between the quality of the evidence and the strength of the recommendations was not a “black box” process but an open, deliberative exercise by skilled experts guided by a rigorous set of standards. Despite the strength and potential value of this document, it is important to acknowledge the inherent limitations of clinical practice guidelines. This, or any other, evidence-based clinical practice guidelines document does not represent the definitive source of knowledge on the stated topic. Rather, it represents recommendations of varying strength and certainty based on an analysis of the best available published data. These data, however, are often conflicting, flawed, or incomplete, and there are unavoidable elements of potential bias from subjectivity, perspective, and experience of the individuals and group involved in the analysis and interpretation of these data. In essence, proof is a relative term based on the interpretation of evidence. Furthermore, it is subject to different standards. A relevant example comes from the field of jurisprudence, where the standard of proof (i.e., guilt) for criminal trials is “beyond a reasonable doubt,” whereas the standard for civil courts must simply reflect “a preponderance of evidence” or “more likely than not.” These different standards evolved because of the perceived different consequences of a wrongful verdict. Moreover, as Stephen Haines likes to note, the verdict “not guilty” does not mean innocent; it merely says not proved. Such are the vagaries associated with the interpretation of even scientific evidence. Principled people can look at the same evidence and come to different conclusions subject to their own personal perspective, experience, and stake in the result. Nevertheless, the Joint Section and Guidelines Development Group went to great lengths to identify and avoid—or at least minimize—these potential problems. The working group adopted the most widely recognized and rigorous standards for guidelines development. A diverse panel of experts with expertise in spine, trauma, and epidemiology brought relevant clinical, scientific, and methodological competence to enhance both the analytical and the deliberative aspects of this process. Periodic outside reviews were routinely obtained for topics or areas of contention or uncertainty to add additional perspective and balance. Above all, the process was accountable and transparent at every stage. Ultimately, we offer these guidelines as a living document to those professionals who treat patients with traumatic spinal injury. We hope each practitioner will critically evaluate these guidelines and come to his or her own conclusion on how, whether, and when to implement its recommendations. It may be used either as a reference or as a basis for standardized protocols of evaluation and management of the patients with traumatic spinal injury. For clinical and basic science researchers, we hope that it will identify and catalyze scientific investigation in areas of deficient knowledge. As a Section, we stand firmly behind this important document and will continuously update the recommendations as new knowledge and understanding is developed. We sincerely believe that these guidelines can improve the care and enhance the outcomes of patients with traumatic injuries to the cervical spine and spinal cord.

Open access
5 source records
Spinal Cord Injury Research
Cervical and Thoracic Myelopathy
Spinal Fractures and Fixation Techniques
Original source
Jan 1, 1969·Transactions of the American Mathematical Society
7 cites
Sturmian theorems and positive resolvents

Kurt Kreith

1. Introduction.The classical Sturmian theorem of ordinary differential equations deals with functions u(x) and v(x) which are, respectively, solutions of differential equations(1) Um-^^j+tumO,(2) Mv=-l{J^+yv = 0.Under the assumption that "F is larger than M" (in the sense that a(x) Ă€ a(x) > 0 and c(x) ÂŁ y(x)) one can infer information about all solutions of (2) from knowledge about a particular nontrivial solution of (1)-i.e. if u(xx) = u(x2)=0 then every solution of (2) has a zero in [xx, x2].These ideas have been generalized to second order elliptic equations by several authors ([l]-[4]) considering elliptic operators and also by Protter [5] and Swanson [6] considering the nonselfadjoint case.Given a proper relation among the coefficients of F and M and that Lu=0 has a nontrivial solution with nodal domain Ü, then it can be shown that every solution of Mv = 0 has a zero in Í2.While all the above proofs of this fact make essential use of some sort of ordering among elliptic operators, the nature of this ordering is never defined in operator-theoretic terms.The results of §2 below suggest that it is an order relationship between certain resolvents of the differential operators F and M which underlies the separation properties characteristic of Sturmian theorems.It will be shown that quite general operator equations in a Banach space 3S satisfy a type of Sturmian theorem if the operators' resolvents satisfy prescribed positivity requirements with respect to a cone SP.In order to apply this theory to differential operators, one must first establish the corresponding positivity properties for their resolvents.This is done in §3 for sufficiently regular nonselfadjoint second order elliptic operators, and the general theory of §2 is then applied in the proof of two Sturmian theorems and the establishment of criteria for certain Green's functions to be positive.

Open access
2 source records
Spectral Theory in Mathematical Physics
Quantum chaos and dynamical systems
Stability and Controllability of Differential Equations
Original source
Jan 1, 1969·Indiana Magazine of History
1 cites
Public Canal Finance and State Banking In Ohio, 18251837

Harry N. Scheiber

Historians have recently given much attention to the active, formative role of state governments in the American economy before the Civil War.1 The states exercised nearly exclusive control over many aspects of economic life, and in such areas as labor, banking, and corporation policy the federal government interfered relatively little. The consequence was considerable decentralization of power in policymaking, together with variations in policy from state to state.2 Perhaps in no policy area were variations so dramatic as in state legislation on banking. In some states banking was prohibited outright, while in others the state government itself established and operated banks, sometimes on a monopoly basis. Elsewhere, safety funds were established and banks required to meet minimum standards of specie reserve and the like; and in a few states, stringent regulatory policies were pursued, with public commissioners given considerable discretion in administering policy.3

Open access
American History and Culture
American Environmental and Regional History
Archaeology and Natural History
Original source