Showing papers by "University of Rochester published in 1996"
TL;DR: The present study shows that a fundamental task of language acquisition, segmentation of words from fluent speech, can be accomplished by 8-month-old infants based solely on the statistical relationships between neighboring speech sounds.
Abstract: Learners rely on a combination of experience-independent and experience-dependent mechanisms to extract information from the environment. Language acquisition involves both types of mechanisms, but most theorists emphasize the relative importance of experience-independent mechanisms. The present study shows that a fundamental task of language acquisition, segmentation of words from fluent speech, can be accomplished by 8-month-old infants based solely on the statistical relationships between neighboring speech sounds. Moreover, this word segmentation was based on statistical learning from only 2 minutes of exposure, suggesting that infants have access to a powerful mechanism for the computation of statistical properties of the language input.
4,352 citations
TL;DR: In this article, the authors studied whether prophylactic therapy with an implanted cardioverter-defibrillator, as compared with conventional medical therapy, would improve survival in this high-risk group of patients.
Abstract: Background Unsustained ventricular tachycardia in patients with previous myocardial infarction and left ventricular dysfunction is associated with a two-year mortality rate of about 30 percent. We studied whether prophylactic therapy with an implanted cardioverter–defibrillator, as compared with conventional medical therapy, would improve survival in this high-risk group of patients. Methods Over the course of five years, 196 patients in New York Heart Association functional class I, II, or III with prior myocardial infarction; a left ventricular ejection fraction <0.35; a documented episode of asymptomatic unsustained ventricular tachycardia; and inducible, nonsuppressible ventricular tachyarrhythmia on electrophysiologic study were randomly assigned to receive an implanted defibrillator (n = 95) or conventional medical therapy (n = 101). We used a two-sided sequential design with death from any cause as the end point. Results The base-line characteristics of the two treatment groups were similar. During...
3,843 citations
TL;DR: In this paper, the authors examine tests for cointegration which allow for the possibility of regime shifts and propose ADF, Z α, Z t and Z t-type tests designed to test the null of no co-integration against the alternative of cointegrations in the presence of a possible regime shift, where the intercept and/or slope coefficients have a single break of unknown timing.
2,438 citations
TL;DR: In this paper, the authors proposed an approach-avoidance achievement goal conceptualization in the intrinsic motivation domain, where only performance goals grounded in the avoidance of failure undermined intrinsic motivation and task involvement was validated as a mediator of the observed effects on intrinsic motivation.
Abstract: nMost contemporary achievement goal conceptualizations consist of a performance goal versus mastery goal dichotomy. The present research offers an alternative framework by partitioning the performance goal orientation into independent approach and avoidance motivational orientations. Two experiments investigated the predictive utility of the proposed approach-avoidance achievement goal conceptualization in the intrinsic motivation domain. Results from both experiments supported the proposed framework; only performance goals grounded in the avoidance of failure undermined intrinsic motivation. Task involvement was validated as a mediator of the observed effects on intrinsic motivation. Ramifications for the achievement goal approach to achievement motivation and future research avenues are discussed. Achievement motivation theorists focus their research attention on a particular class of behaviors, those involving competence. Individuals may aspire to attain competence or may strive to avoid incompetence, and this approach-avoidance distinction was explicitly incorporated into the earliest achievement motivation conceptualizations. Two independent motivational orientations, the desire for success and the desire to avoid failure, were identified by Lewin and colleagues as critical determinants of aspiration behavior (Hoppe, cited in Lewin, Dembo, Festinger, & Sears, 1944). In his nascent achievement motivation theory, McClelland ( 1951 ) proposed that "there are at least two kinds of achievement motivation, one of which appears to be oriented around avoiding failure and the other around the more positive goal of attaining success" (p. 202).
2,292 citations
TL;DR: This paper found that the relative importance and efficacy of extrinsic aspirations for financial success, an appealing appearance, and social recognition were associated with lower vitality and self-actualization and more physical symptoms.
Abstract: Empirical research and organismic theories suggest that lower well-being is associated with having extrinsic goals focused on rewards or praise relatively central to one's personality in comparison to intrinsic goals congruent with inherent growth tendencies. In a sample of adult subjects (Study 1), the relative importance and efficacy of extrinsic aspirations for financial success, an appealing appearance, and social recognition were associated with lower vitality and self-actualization and more physical symptoms. Conversely, the relative importance and efficacy of intrinsic aspirations for self-acceptance, affiliation, community feeling, and physical health were associated with higher well-being and less distress. Study 2 replicated these findings in a college sample and extended them to measures of narcissism and daily affect. Three reasons are discussed as to why extrinsic aspirations relate negatively to well-being, and future research directions are suggested.
2,246 citations
TL;DR: In this article, positional cloning was used to establish KVLQT1 as the chromosome 11-linked LQT 1 gene responsible for the most common inherited cardiac arrhythmia.
Abstract: Genetic factors contribute to the risk of sudden death from cardiac arrhythmias. Here, positional cloning methods establish KVLQT1 as the chromosome 11-linked LQT1 gene responsible for the most common inherited cardiac arrhythmia. KVLQT1 is strongly expressed in the heart and encodes a protein with structural features of a voltage-gated potassium channel. KVLQT1 mutations are present in affected members of 16 arrhythmia families, including one intragenic deletion and ten different missense mutations. These data define KVLQT1 as a novel cardiac potassium channel gene and show that mutations in this gene cause susceptibility to ventricular tachyarrhythmias and sudden death.
1,714 citations
TL;DR: In this paper, a new class of long-period fiber gratings that can be used as in-fiber, low-loss, band-rejection filters is presented.
Abstract: We present a new class of long-period fiber gratings that can be used as in-fiber, low-loss, band-rejection filters. Photoinduced periodic structures written in the core of standard communication-grade fibers couple light from the fundamental guided mode to forward propagating cladding modes and act as spectrally selective loss elements with insertion losses act as backreflections <-80 dB, polarization-mode-dispersions <0.01 ps and polarization-dependent-losses <0.02 dB.
1,696 citations
TL;DR: These findings shed light on the biochemical function of the evolutionarily conserved Gcn5p-Ada complex, directly linking histone acetylation to gene activation, and indicate that histoneacetylation is a targeted phenomenon.
1,609 citations
TL;DR: Testing the theory with 128 patients in a 6-month, very-low-calorie weight-loss program confirmed the predictions that participants whose motivation for weight loss was more autonomous would attend the program more regularly, lose more weight during the program, and evidence greater maintained weight loss at follow-up.
Abstract: Self-determination theory proposes that behavior change will occur and persist if it is autonomously motivated. Autonomous motivation for a behavior is theorized to be a function both of individual differences in the autonomy orientation from the General Causality Orientations Scale and of the degree of autonomy supportiveness of relevant social contexts. We tested the theory with 128 patients in a 6-month, very-low-calorie weight-loss program with a 23-month follow-up. Analyses confirmed the predictions that (a) participants whose motivation for weight loss was more autonomous would attend the program more regularly, lose more weight during the program, and evidence greater maintained weight loss at follow-up, and (b) participants' autonomous motivation for weight loss would be predicted both by their autonomy orientation and by the perceived autonomy supportiveness of the interpersonal climate created by the health-care staff.
1,487 citations
TL;DR: Cicchetti et al. as mentioned in this paper used equifinality to explain why in any open system (i.e., one come have been conceived as among the hall where there is maintenance in change, dymarks of the developmental psychopathology namic order of processes, organization, selfperspective) the same end state may be mezy & Streitman, 1974; Kohlberg, Lareached from a variety of different initial conCrosse, & Riclcs, 1972; Sameroff, 1989; ditions and through different processes.
Abstract: Since its inception as an emergent interdisciepigenesis, may lead to the same outcome, plinary science, diversity in process and outStated differently, in an open system (i.e., one come have been conceived as among the hallwhere there is maintenance in change, dymarks of the developmental psychopathology namic order of processes, organization, selfperspective (Cicchetti, 1984, 1990; Garregulation, etc.) the same end state may be mezy & Streitman, 1974; Kohlberg, Lareached from a variety of different initial conCrosse, & Riclcs, 1972; Sameroff, 1989; ditions and through different processes. This Sroufe, 1986, 1989; Sroufe & Rutter, 1984). is referred to as equifinality, an organismic Thus, developmental psychopathologists have process that possesses significant implications articulated the expectations that there are mulfor psychological and biological regulatory tiple contributors to adaptive or maladaptive systems (Cicchetti, 1996) and for behavioral outcomes in any individual, that these factors and biological plasticity (Cicchetti & Tucker, and their relative contributions vary among 1994b). In contrast, in a closed system the end individuals, and that there are myriad pathstate is inextricably linked to and determined ways to any particular manifestation of adapby the initial conditions: if either the conditive or disordered behavior (Cicchetti, 1993; tions change or the processes are modified, Richters & Cicchetti, 1993; Robins, 1966; then the end state will also be modified (von Robins & Rutter, 1990; Rutter, 1989, 1995; Bertalanffy, 1968). Sroufe & Jacobvitz, 1989). Additionally, it is Initial descriptions of equifinality emabelieved that there is heterogeneity among innated from work in embryology. For example, dividuals who develop a specific disorder the development of a normal organism was with respect to the features of their disturbshown to occur from a whole ovum, a divided ance, as well as among individuals who eviovum, or two fused ova. Further, it was demdence maladaptation but who do not develop onstrated that different initial sizes and differa disorder. In accord with this view, the prinent courses of growth can eventuate in the ciples of equifinality and multifinality derived same ultimate size of an organism (von Bertafrom general systems theory (von Bertalanffy, lanffy, 1968; Waddington, 1957). Within the 1968) are germane. discipline of developmental psychopathology, Equifinality refers to the observation that equifinality has been invoked to explain why in any open system (cf. Mayr, 1964, 1988) a a variety of developmental pathways may diversity of pathways, including chance eventuate in a given outcome, rather than exevents or what biologists refer to as nonlinear pecting a singular primary pathway to the adaptive or maladaptive outcome. Address correspondence to: Dr. Dante Cicchetti or Dr. T h e Principle of multifinality (Wilden, Fred A. Rogosch, Mt. Hope Family Center, Univ. of 1980) suggests that any one component may Rochester, 187 Edinburgh St., Rochester, NY 14608. function differently depending on the organi-
1,476 citations
TL;DR: Students who perceived their instructors as more autonomy-supportive became more autonomous in their learning, which in turn accounted for a significant increase in both perceived competence and psychosocial beliefs over the 20-week period of the course.
Abstract: Two studies, tested self-determination theory with 2nd-year medical students in an interviewing course Study I revealed that (a) individuals with a more autonomous orientation on the General Causality Orientations Scale had higher psychosocial beliefs at the beginning of the course and reported more autonomous reasons for participating in the course, and (b) students who perceived their instructors as more autonomy-supportive became more autonomous in their learning during the 6-month course Study 2, a 30-month longitudinal study, revealed that students who perceived their instructors as more autonomy-supportive became more autonomous in their learning, which in turn accounted for a significant increase in both perceived competence and psychosocial beliefs over the 20-week period of the course, more autonomy support when interviewing a simulated patient 6 months later, and stronger psychosocial beliefs 2 years later
TL;DR: Intraperitoneal cisplatin significantly improves survival and has significantly fewer toxic effects in patients with stage III ovarian cancer and residual tumor masses of 2 cm or less.
Abstract: Background Intravenous platinum-based chemotherapy is the standard primary therapy for advanced ovarian cancer. We conducted a phase 3 trial to compare the effects of intraperitoneal and intravenous cisplatin on the survival of women with previously untreated, stage III, epithelial ovarian cancer. Methods The patients underwent an initial exploratory laparotomy and resection of all tumor masses larger than 2 cm. Within four weeks after surgery, six courses of intravenous cyclophosphamide (600 mg per square meter of body-surface area per course) plus either intraperitoneal cisplatin (100 mg per square meter) or intravenous cisplatin (100 mg per square meter) were administered at three-week intervals. Results Of 654 randomized patients, 546 were eligible for the study. The estimated median survival was significantly longer in the group receiving intraperitoneal cisplatin (49 months; 95 percent confidence interval, 42 to 56) than in the group receiving intravenous cisplatin (41 months; 95 percent confidence ...
TL;DR: This article showed that distributional cues may play an important role in the initial word segmentation of language learners, and that the addition of certain prosodic cues served to enhance performance of infants.
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01 Jan 1996TL;DR: This chapter discusses the architecture and components of the Electronic Commerce Framework, and some of the issues surrounding the design and implementation of EDI in the real-time environment.
Abstract: 1. Welcome to Electronic Commerce. Electronic Commerce Framework. Electronic Commerce and Media Convergence. The Anatomy of E-Commerce Applications. Electronic Commerce Consumer Applications. Electronic Commerce Organization Applications. Summary. 2. The Network Infrastructure for Electronic Commerce. Market Forces Influencing the I-Way. Components of the I-Way. Network Access Equipment. The Last Mile: Local Roads and Access Ramps. Global Information Distribution Networks. Public Policy Issues Shaping the I-Way. Summary. 3. The Internet as a Network Infrastructure. The Internet Terminology. Chronological History of the Internet. NSFNET: Architecture and Components. National Research and Education Network. Globalization of the Academic Internet. Internet Governance: The Internet Society. An Overview of Internet Applications. Summary. 4. The Business of Internet Commercialization. Telco/Cable/On-Line Companies. National Independent ISPs. Regional-Level ISPs. Local-Level ISPs. Service Providers Abroad. Service Provider Connectivity: Network Interconnection Points. Internet Connectivity Options. Logistics of Being an Internet Service Provider. Summary. 5. Network Security and Firewalls. Client-Server Network Security. Emerging Client-Server Security Threats. Firewalls and Network Security. Data and Message Security. Challenge-Response Systems. Encrypted Documents and Electronic Mail. U.S. Government Regulations and Encryption. Summary. 6. Electronic Commerce and World Wide Web. Architectural Framework for Electronic Commerce. World Wide Web (WWW) as the Architecture. Web Background: Hypertext Publishing. Technology behind the Web. Security and the Web. Summary. 7. Consumer-Oriented Electronic Commerce. Consumer-Oriented Applications. Mercantile Process Models. Mercantile Models from the Consumers Perspective. Mercantile Models from the Merchants Perspective. Summary. 8. Electronic Payment Systems. Types of Electronic Payment Systems. Digital Token-Based Electronic Payment Systems. Smart Cards and Electronic Payment Systems. Credit Card-Based Electronic Payment Systems. Risk and Electronic Payment Systems. Designing Electronic Payment Systems. Summary. 9. Interorganizational Commerce and EDI. Electronic Data Interchange. EDI Applications in Business. EDI: Legal, Security, and Privacy Issues. EDI and Electronic Commerce. Summary. 10. EDI Implementation MIME, and Value-Added Networks. Standardization and EDI. EDI Software Implementation. EDI Envelope for Message Transport. Value-Added Networks (VANs). Internet-Based EDI. Summary. 11. Intraorganizational Electronic Commerce. Internal Information Systems. Macroforces and Internal Commerce. Work-flow Automation and Coordination. Customization and Internal Commerce. Supply Chain Management (SCM). Summary. 12. The Corporate Digital Library. Dimensions of Internal Electronic Commerce Systems. Making a Business Case for a Document Library. Types of Digital Documents. Issues behind Document Infrastructure. Corporate Data Warehouses. Summary. 13. Advertising and Marketing on the Internet. The New Age of Information-Based Marketing. Advertising on the Internet. Charting the On-Line Marketing Process. Market Research. Summary. 14. Consumer Search and Resource Discovery. Search and Resource Discovery Paradigms. Information Search and Retrieval. Electronic Commerce Catalogs or Directories. Information Filtering. Consumer-Data Interface: Emerging Tools. Summary.
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23 Dec 1996TL;DR: This chapter discusses Electronic Commerce and Banking, the Internet and the Access Provider Industry, and the role of Java in Electronic Commerce.
Abstract: 1. Introduction to Electronic Commerce. Defining Electronic Commerce. Brief History of Electronic Commerce. Forces Fueling Electronic Commerce. Electronic Forces. Marketing and Customer Interaction Forces. Technology and Digital Convergence. Implications of Various Forces. Electronic Commerce Industry Framework. The Information Superhighway. Multimedia Content and Network Publishing. Messaging and Information Distribution. Common Business Services Infrastructure. Other Key Support Layers. Putting the Framework into Action: Microsoft Corporation. Types of Electronic Commerce. Inter-organizational Electronic Commerce. Intra-organizational Electronic Commerce. Consumer-to-Business Electronic Commerce. Intermediaries and Electronic Commerce. Key Questions for Management. Competitive Pressure. External Threat. Incorporating Changes. Designing New Organizational Structures. Managerial Options and Priorities. Summary. 2. The Internet and the Access Provider Industry. Internet Service Providers. Key Market Drivers for the Internet. Who Is Making Money on the Internet. Clarifying Internet Terminology. Companies Providing Internet Access. Internet Topology. Differentiating Market Segments: Commercial versus Consumer. Internet versus Online Services. Open versus Closed Architecture. Controlled Content versus Uncontrolled Content. Metered Pricing versus Flat Pricing. Innovation versus Control. Predicting the Future of the IAP Market. Convergence Leading to Competition. Service and Capacity Management. Customer Service, Loyalty, and Retention. Marketing. Customer Education. Changing Technology behind Internet Access. Changing Technology behind the Access Provider. Summary. 3. World Wide Web--Applications. Brief History of the Web. What Exactly Is the Web? Why Is the Web Such a Hit? The Web and Ease of Use. The Web and Ease of Publishing. The Web as a New Distribution Channel. The Web and Network-Centric Computing. The Web and New Intra-Business Applications. The Web and Electronic Commerce. The Web and Intra-Business Commerce. Other Intranet Applications. Intranet Advantages and Disadvantages. Management of Intranets. Understanding the Intranet Architecture. Summary. 4. World Wide Web--Concepts and Technology. Key Concepts behind the Web. Overview of the Web's Technical Architecture. Interactive Web Applications. Interactive Applications. Interactivity and Information Integration. Web Extensions for Interactive Applications. Web and Database Integration. Web Database Products. HTML Forms and CGI Programs. Web Software Developmental Tools. Need for Better Programming Languages. New Programming Language: Java. Technically Speaking: What Exactly Is Java? Role of Java in Electronic Commerce. How Does Java Work? Business Reasons for Using Java. Multimedia Web Extensions. Virtual Reality Modeling Language (VRML). RealAudio. Internet and Web-based Telephony. Directories and Search Engines. Lycos. Summary. 5. Firewalls and Transaction Security. Firewalls and Network Security. Types of Firewalls. Firewall Security Policies. Emerging Firewall Management Issues. Transaction Security. Types of Online Transactions. Requirements for Transaction Security. Encryption and Transaction Security. Secret-Key Encryption. Public-Key Encryption. Implementation and Management Issues. World Wide Web and Security. Netscape's Secure Sockets Layer. Security and Online Web-based Banking. Summary. 6. Electronic Payment Systems. Overview of the Electronic Payment Technology. The Online Shopping Experience. Limitations of Traditional Payment Instruments. Electronic or Digital Cash. Properties of Electronic Cash. Digital Cash in Action. Electronic Checks. Benefits of Electronic Checks. Electronic Checks in Action. NetCheck: A Prototype Electronic Check System. Electronic Check Project. Online Credit Card-Based Systems. Types of Credit Card Payments. Secure Electronic Transactions (SET). Other Emerging Financial Instruments. Debit Cards at the Point of Sale (POS). Debit Cards and Electronic Benefits Transfer. Smart Cards. Consumer, Legal, and Business Issues. Summary. 7. Electronic Commerce and Banking. Changing Dynamics in the Banking Industry. Changing Consumer Needs. Cost Reduction. Demographic Trends. Regulatory Reform. Technology-based Financial Services Products. Home Banking History. Why Will It Be Different This Time? Home Banking Implementation Approaches. Home Banking Using Bank's Proprietary Software. Banking via the PC Using Dial-Up Software. Banking via Online Services. Banking via the Web: Security First Network Bank. Open versus Closed Models. Management Issues in Online Banking. Differentiating Products and Services. Managing Financial Supply Chains. Pricing Issues in Online Banking. Marketing Issues: Attracting Customers. Marketing Issues: Keeping Customers. Back-Office Support for Online Banking. Integrating Telephone Call Centers with the Web. Summary. 8. Electronic Commerce and Retailing. Changing Retail Industry Dynamics. Overbuilding and Excess Capacity. Demographic Changes. Consumer Behavior. Technology Improvements in Electronic Retailing. Online Retailing Success Stories. Online Retailing: Peapod's Experience. CUC International. Wine on the Web: Virtual Vineyards. Web-based Travel Agencies. Mercantile Models from the Consumer's Perspective. Distinct Phases of a Consumer Mercantile Model. Prepurchase Preparation. Purchase Consummation. Postpurchase Interaction. Management Challenges in Online Retailing. Come Up with a Retailing Strategy. Manage Channel Conflict. Learn to Price Online Products/Services. Deliver a Satisfying Shopping Experience. Design the Layout of an Online Store. Manage Brands. Create the Right Incentives. Summary. 9. Electronic Commerce and Online Publishing. Why Online Publishing? Online Publishing Strategies. Online Publishing Approaches. Full-Text and Bibliographic Databases. Personalized and Customized News. Business Information and News Delivery. Edutainment = Education + Entertainment. Online Publishing Success Stories. PointCasting. Time Warner's Pathfinder. Disney Online. Integrating TV and Data Streams: Intercasting. Advertising and Online Publishing. An Online Publishing Missing Piece: Measurement. Digital Copyrights and Electronic Publishing. Online Copyright Protection Methods. Summary. 10. Intranets and Supply-Chain Management. Supply-Chain Management Fundamentals. Pull versus Push Supply-Chain Models. Elements of Supply-Chain Management. Integrating Functions in a Supply Chain. Managing Retail Supply Chains. The Order Management Cycle (OMC). Supply-Chain Application Software. Software for Supply-Chain Management. Recent Trends in Application Software. What Is the Business Market? Understanding the Application Software Architecture. Future of Supply-Chain Software. Intranets and Network-Centric Computing. Intranets and Application Software. Impact of the Web on Application Software. Elaborating on the Intranet Architecture. What Remains to Be Done? Summary. 11. Intranets and Customer Asset Management. Why Customer Asset Management? Challenges in Implementing Customer Asset Management. Customer Asset Management and Supply Chains. Online Sales Force Automation. What Is Sales Force Automation? Elements of Online Sales Automation. Intranets and Sales Automation. What Are the Management Issues? Online Customer Service and Support. The Web and Customer Service. The Role of Technology in Customer Service. What Are the Business Requirements? The Enabling Intranet Technology. Technology and Marketing Strategy. Marketing Decision Support Systems. Marketing Decision Support Applications. Summary. 12. Intranets and Manufacturing. Defining the Terminology. Integrated Logistics. Agile Manufacturing. Emerging Business Requirements. Customer-Driven Manufacturing. Rapid Internal Response to Demand Changes. Efficiently Managing Supply Chain Complexity. Manufacturing Information Systems. Discrete versus Process Manufacturing Market. Types of Manufacturing Information Systems. Intranet-Based Manufacturing. Customer-Driven Manufacturing. Real-Time Decision Support. Intelligent Process Management. Logistics Management. Problems with Traditional Logistics Management. Case Study: Microsoft Corp Integrated Logistics. Objective of Modern Logistics Function. Forecasting. Purchasing. Distribution Management. Electronic Data Interchange (EDI). Benefits of EDI. EDI in Action. Why Has EDI Adoption Lagged? Summary. 13. Intranets and Corporate Finance. Intranets and Finance. What Exactly Are Financial Systems? What Do Financial Systems Do? Financial Intranets. Understanding the Different Software Modules. Transaction Accounting and Electronic Commerce. Financial Analysis and Management Accounting. Inventory Accounting. Payment Management. Treasury and Cash Management. Human Resources Management Systems. HRMS Functions. Size/Structure of Financials Software Market. Product Strategy. Financial Data Warehouses. How Are Firms Using the Web for OLAP? Desirable Software Requirements. Summary. 0201880679T04062001
TL;DR: Deictic computation provides a mechanism for representing the essential features that link external sensory data with internal cognitive programs and motor actions and this target article focuses on how deictic bindings make it possible to perform natural tasks.
Abstract: To describe phenomena that occur at different time scales, computational models of the brain necessarily must incorporate different levels of abstraction. We argue that at time scales of approximately one-third of a second, orienting movements of the body play a crucial role in cognition and form a useful computational level, termed the embodiment level. At this level, the constraints of the body determine the nature of cognitive operations, since the natural sequentiality of body movements can be matched to the natural computational economies of sequential decision systems. The way this is done is through a system of implicit reference termed deictic, whereby pointing movements are used to bind objects in the world to cognitive programs. We show how deictic bindings enable the solution of natural tasks and argue that one of the central features of cognition, working memory, can be related to moment-by-moment dispositions of body features such as eye movements and hand movements.
TL;DR: The Condorcet Jury Theorem states that majorities are more likely than any single individual to select the "better" of two alternatives when there exists uncertainty about which of the two alternatives is in fact preferred as discussed by the authors.
Abstract: The Condorcet Jury Theorem states that majorities are more likely than any single individual to select the "better" of two alternatives when there exists uncertainty about which of the two alternatives is in fact preferred Most extant proofs of this theorem implicitly make the behavioral assumption that individuals vote "sincerely" in the collective decision making, a seemingly innocuous assumption, given that individuals are taken to possess a common preference for selecting the better alternative However, in the model analyzed here we find that sincere behavior by all individuals is not rational even when individuals have such a common preference In particular, sincere voting does not constitute a Nash equilibrium A satisfactory rational choice foundation for the claim that majorities invariably "do better" than individuals, therefore, has yet to be derived
01 May 1996
TL;DR: Experiments on a 12-node SGI Challenge multiprocessor indicate that the new non-blocking queue consistently outperforms the best known alternatives; it is the clear algorithm of choice for machines that provide a universal atomic primitive (e.g., compare_and_swap or load_linked/store_conditional).
Abstract: Drawing ideas from previous authors, we present a new non-blocking concurrent queue algorithm and a new two-lock queue algorithm in which one enqueue and one dequeue can proceed concurrently. Both algorithms are simple, fast, and practical; we were surprised not to find them in the literature. Experiments on a 12-node SGI Challenge multiprocessor indicate that the new non-blocking queue consistently outperforms the best known alternatives; it is the clear algorithm of choice for machines that provide a universal atomic primitive (e.g., compare_and_swap or load_linked/store_conditional). The two-lock concurrent queue outperforms a single lock when several processes are competing simultaneously for access; it appears to be the algorithm of choice for busy queues on machines with non-universal atomic primitives (e.g., test_and_set). Since much of the motivation for non-blocking algorithms is rooted in their immunity to large, unpredictable delays in process execution, we report experimental results both for systems with dedicated processors and for systems with several processes multiprogrammed on each processor.
TL;DR: In this article, a Doppler-derived index, combining systolic and diastolic intervals of the right cycle, was used to assess global right ventricular function in patients with primary pulmonary hypertension.
Abstract: Echocardiographic assessment of right ventricular function remains difficult and challenging. However, there is considerable clinical need for a simple, reproducible, and reliable parameter of right ventricular function in patients with right-sided heart disease. The purpose of this study was to assess the clinical value of a Doppler-derived index, combining systolic and diastolic intervals of the right cycle, in assessing global right ventricular function in patients with primary pulmonary hypertension. The study population comprised 26 consecutive patients with primary pulmonary hypertension and 37 age-matched normal subjects. The sum of right ventricular isovolumetric contraction time and isovolumetric relaxation time was obtained by subtracting right ventricular ejection time from the interval between cessation and onset of the tricuspid inflow velocities with pulsed-wave Doppler echocardiography. An index of combined right ventricular systolic and diastolic function was obtained by dividing the sum of both isovolumetric intervals by ejection time. The index was compared with available parameters of systolic or diastolic function, clinical symptoms, and survival. Right ventricular isovolumetric contraction time and isovolumetric relaxation time were prolonged significantly in patients with primary pulmonary hypertension (85 ± 41 msec and 135 ± 43 msec) compared with normal subjects (38 ± 7 msec and 49 ± 9 msec, respectively; p p p
TL;DR: In this article, the authors studied the relation between the premiums in takeover bids involving exchange-listed target firms from 1975-91 and the pre-announcement stock price runups.
TL;DR: In this paper, a diary study examined the proposal that satisfaction of two psychological needs, competence and autonomy, leads to daily well-being and found that participants higher in trait competence and trait autonomy tended to have "better" days on average.
Abstract: This diary study examined the proposal that satisfaction of two psychological needs, competence and autonomy, leads to daily well-being. Between-subjects analyses indicated that participants higher in trait competence and trait autonomy tended to have "better" days on average. Independently, within-subject analyses showed that good days were those in which participants felt more competent and autonomous in their daily activities, relative to their own baselines. Other predictors of daily well-being included gender, whether the day fell on a weekend, and the amount of negative affect and physical symptomatology felt the day before. Although past diary studies have tended to focus on threats to daily well-being, the authors suggest that psychological need concepts offer promise for understanding its positive sources.
TL;DR: In this article, the authors demonstrate the successful integration of silicon-based visible light-emitting devices into a standard bipolar microelectronic circuit by exploiting the thermal and chemical stability of porous silicon.
Abstract: MICROELECTRONIC device integration has progressed to the point where complete 'systems-on-a-chip' have been realized1–3. Now that optoelectronics is becoming increasingly important for information and communication technologies, there is a need to develop optoelectronic devices that can be integrated with standard microelectronics. Conventional semiconductor technology is largely based on crystalline silicon, which (being an indirect bandgap semiconductor) is an inefficient light-emitting material. This has stimulated significant effort towards developing silicon-based optoelectronic components and, of the several strategies explored so far4,5, the use of porous silicon appears the most promising; porous silicon produces high-efficiency, room-temperature, visible photoluminescence6, and its material and optical properties have been studied in detail7,8. But the extreme reactivity and fragility of porous silicon have hitherto prevented its integration with conventional silicon processing technology. We have recently shown9,10 that the thermal and chemical stability of porous silicon can be greatly enhanced — while retaining desirable light-emitting and charge-transport properties — by partial oxidation. Here we take advantage of these improvements in material properties to demonstrate the successful integration of silicon-based visible light-emitting devices into a standard bipolar microelectronic circuit.
TL;DR: A new classification scheme of lesional activity on the basis of the molecular composition of myelin degradation products in macrophages is presented and it is indicated, that the demyelinated plaques of multiple sclerosis may reflect a common pathological end point of a variety of different immunological mechanisms ofMyelin destruction in this disease.
Abstract: Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system. The hallmark of its pathology is the demyelinated plaque with reactive glial scar formation. However, a detailed analysis of the patterns of demyelination, oligodendroglia cell pathology and the reaction of other tissue components suggests that the pathogenesis of myelin destruction in this disease may be heterogeneous. In this review we present a new classification scheme of lesional activity on the basis of the molecular composition of myelin degradation products in macrophages. When these criteria are used, different patterns of demyelination can be distinguished, including demyelination with relative preservation of oligodendrocytes, myelin destruction with concomitant and complete destruction of oligodendrocytes or primary destruction or disturbance of myelinating cells with secondary demyelination. Furthermore, in some cases a primary selective demyelination may be followed by a secondary oligodendrocyte loss in the established lesions. Finally, some extraordinarily severe conditions may result in destructive lesions with loss of myelin, oligodendrocytes, axons and astrocytes. This heterogeneity of plaque pathology is discussed in the context of recent experimental models of inflammatory demyelination, which show that different immunological pathways may lead to the formation of demyelinated plaques that reveal the diverse structural aspects described above. Our data indicate, that the demyelinated plaques of multiple sclerosis may reflect a common pathological end point of a variety of different immunological mechanisms of myelin destruction in this disease.
TL;DR: Evidence is presented that human TAF(II)250 and its homologs in Drosophila and yeast have histone acetyltransferase (HAT) activity in vitro, which suggests that targeted hist one acetylation at specific promoters by TAF (II) 250 may be involved in mechanisms by which TFIID gains access to transcriptionally repressed chromatin.
TL;DR: This drug combination reduced HIV-1 replication, increased CD4+ cell counts, and decreased levels of activation markers in serum more than did treatment with zidovudine and either saquinavir or zalcitabine.
Abstract: Background In patients with human immunodeficiency virus (HIV) infection, combined treatment with several agents may increase the effectiveness of antiviral therapy. We studied the safety and efficacy of saquinavir, an HIV-protease inhibitor, given with one or two nucleoside antiretroviral agents, as compared with the safety and efficacy of a combination of two nucleosides alone. Methods In this double-blind trial, patients with HIV infection were randomly assigned to receive either saquinavir (1800 mg per day) plus both zidovudine (600 mg per day) and zalcitabine (2.25 mg per day) or zidovudine plus either saquinavir or zalcitabine. The 302 patients enrolled had CD4+ counts of 50 to 300 cells per cubic millimeter and had previously received zidovudine for a median of 27 months. The study lasted 24 weeks, with an optional double-blind extension period of an additional 12 to 32 weeks. Results Ninety-six percent of the patients completed the 24-week study. In all three treatment groups, CD4+ cell counts ros...
TL;DR: It is suggested that risk for suicide increases with age in individuals with major affective illness, and depressed elderly men are particular targets for suicide prevention strategies.
Abstract: OBJECTIVE: Psychiatric illness is a potent risk factor for suicide, rates of which differ markedly with age. The purpose of this study was to examine whether the psychiatric diagnoses of suicide victims vary predictably with age. METHOD: DSM-III-R axis I diagnoses of 141 persons aged 21 to 92 years who had completed suicide were established by the psychological autopsy method. Multiple logistic regression analyses were used to determine whether age, gender, or their interaction predicted the presence of specific disorders. RESULTS: One or more axis I conditions were diagnosable in 90.1% of the suicide victims. Substance use disorders were most frequent, followed by mood disorders and primary psychotic illness. Younger age at death was a significant predictor of substance abuse or dependence and primary psychoses, while older age predicted major mood disorders. Comorbidity of substance use and mood disorders was common. Among victims with substance abuse or dependence, older age at death predicted major depression; among victims with mood disorders, younger age at death predicted comorbid substance abuse or dependence. CONCLUSIONS: The distribution of psychiatric illnesses in suicide victims differs across the life course. Age-related patterns of addictive and psychotic disorders echo their prevalence in the general population. In contrast, the relationship between age and mood disorders among suicide victims is distinctly different from that of the general population. These findings suggest that risk for suicide increases with age in individuals with major affective illness. Depressed elderly men are particular targets for suicide prevention strategies. Language: en
TL;DR: Patients faced with serious medical decisions are subject to being over- or under-influenced by physicians, and data from SUPPORT suggest that the dominant mode of decision making in acute care hospitals may still be the paternalism evidenced by Dr. Able.
Abstract: Medical care in the United States has rapidly moved away from a paternalistic approach to patients and toward an emphasis on patient autonomy. At one extreme end of this spectrum is the "independent choice" model of decision making, in which physicians objectively present patients with options and odds but withhold their own experience and recommendations to avoid overly influencing patients. This model confuses the concepts of independence and autonomy and assumes that the physician's exercise of power and influence inevitably diminishes the patient's ability to choose freely. It sacrifices competence for control, and it discourages active persuasion when differences of opinion exist between physician and patient. This paper proposes an "enhanced autonomy" model, which encourages patients and physicians to actively exchange ideas, explicitly negotiate differences, and share power and influence to serve the patient's best interests. Recommendations are offered that promote an intense collaboration between patient and physician so that patients can autonomously make choices that are informed by both the medical facts and the physician's experience.
TL;DR: The "pathogenicity island" harboring the spi genes may encode the virulence determinants that set Salmonella apart from other enteric pathogens.
Abstract: We have identified a region unique to the Salmonella typhimurium chromosome that is essential for virulence in mice. This region harbors at least three genes: two (spiA and spiB) encode products that are similar to proteins found in type III secretion systems, and a third (spiR) encodes a putative regulator. A strain with a mutation in spiA was unable to survive within macrophages but displayed wild-type levels of epithelial cell invasion. The culture supernatants of the spi mutants lacked a modified form of flagellin, which was present in the supernatant of the wild-type strain. This suggests that the Spi secretory apparatus exports a protease, or a protein that can alter the activity of a secreted protease. The "pathogenicity island" harboring the spi genes may encode the virulence determinants that set Salmonella apart from other enteric pathogens.
Columbia University1, Boston University2, University of Rochester3, Memorial Hospital of South Bend4, Stony Brook University5, Icahn School of Medicine at Mount Sinai6, Henry Ford Health System7, Tufts University8, University of Maryland, Baltimore9, Georgetown University10, Ohio State University11, Yeshiva University12, GlaxoSmithKline13
TL;DR: In a multicenter trial as mentioned in this paper, patients with moderate to severe heart failure (6-minute walk distance, 150 to 450 m) and a left ventricular ejection fraction ≤ 0.35 at 31 centers were randomly assigned to either placebo or carvedilol for 6 months, while background therapy with digoxin, diuretics and an ACE inhibitor remained constant.
Abstract: Background Carvedilol has improved the symptomatic status of patients with moderate to severe heart failure in single-center studies, but its clinical effects have not been evaluated in large, multicenter trials. Methods and Results We enrolled 278 patients with moderate to severe heart failure (6-minute walk distance, 150 to 450 m) and a left ventricular ejection fraction ≤0.35 at 31 centers. After an open-label, run-in period, each patient was randomly assigned (double-blind) to either placebo (n=145) or carvedilol (n=133; target dose, 25 to 50 mg BID) for 6 months, while background therapy with digoxin, diuretics, and an ACE inhibitor remained constant. Compared with placebo, patients in the carvedilol group had a greater frequency of symptomatic improvement and lower risk of clinical deterioration, as evaluated by changes in the NYHA functional class (P=.014) or by a global assessment of progress judged either by the patient (P=.002) or by the physician (P<.001). In addition, treatment with carvedilol...