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PubMed1996

Intuition and expertise: comments on the Benner debate.

The rift between "science' and "phenomenology' in current nursing theory is explored through an examination of two recent evaluations of the work of Patricia Benner, who has proposed a model of skill acquisition, latterly within a Heideggerian framework. English offers a critique of Benner's ideas from the perspective of cognitive psychology; while Darbyshire defends them against what he describes as a "positivist' attack. No attempt is made, in this paper, to evaluate Benner's work directly, but Darbyshire's response to the "critique' is analysed; and it is noted that, in making his defence, he invokes a network of concepts which he ascribes to a "traditional notion of objective science', and accuses English of subscribing to it. It is suggested that this "Cartesian' worldview is an outmoded myth, superseded by the philosophy of science during the last 30 years, and based on the rhetoric rather than the reality of scientific practice. Nursing is not, therefore, obliged to choose between "positivism' and a philosophy whose chief virtue is that it represents a "challenge' to positivism. It could instead build a scientific basis for research and theory by drawing, not on mid-century thinking, but on a more contemporary understanding of the nature of science.

Clinical Competence↗
PubMed1997

Current perspectives and opportunities for international cooperation for development of polymer based drug delivery systems.

The present paper is devoted to: Analysis of significant endeavours directed to polymer base drug delivery systems, elucidating addressing priority problems and biopolymer development, significant R & D needs and priorities and the framework as well as the requirements for international networking in the area of drug delivery system. Such organized collaboration will enable promotion of knowledge among interested parties and cultures. Concerned pharmaceutical institutional and scientific associations e.g. International Pharmaceutical Federation FIP and American Association of Pharmaceutical Sciences AAPS should adopt and initiate planned activities for developing and activation of appropriate drug network encompassing active members from the academic, professional centres and drug industry. The proposed network should be established on a self-sustained basis.

Journal Article↗
PubMed2004

Trophic support delays but does not prevent cell-intrinsic degeneration of neurons deficient for munc18-1.

The stability of neuronal networks is thought to depend on synaptic transmission which provides activity-dependent maintenance signals for both synapses and neurons. Here, we tested the relationship between presynaptic secretion and neuronal maintenance using munc18-1-null mutant mice as a model. These mutants have a specific defect in secretion from synaptic and large dense-cored vesicles [Verhage et al. (2000), Science, 287, 864-869; Voets et al. (2001), Neuron, 31, 581-591]. Neuronal networks in these mutants develop normally up to synapse formation but eventually degenerate. The proposed relationship between secretion and neuronal maintenance was tested in low-density and organotypic cultures and, in vivo, by conditional cell-specific inactivation of the munc18-1 gene. Dissociated munc18-1-deficient neurons died within 4 days in vitro (DIV). Application of trophic factors, insulin or BDNF delayed degeneration up to 7 DIV. In organotypic cultures, munc18-1-deficient neurons survived until 9 DIV. On glial feeders, these neurons survived up to 10 DIV and 14 DIV when insulin was applied. Co-culturing dissociated mutant neurons with wild-type neurons did not prolong survival beyond 4 DIV, but coculturing mutant slices with wild-type slices prolonged survival up to 19 DIV. Cell-specific deletion of munc18-1 expression in cerebellar Purkinje cells in vivo resulted in the specific loss of these neurons without affecting connected or surrounding neurons. Together, these data allow three conclusions. First, the lack of synaptic activity cannot explain the degeneration in munc18-1-null mutants. Second, trophic support delays but cannot prevent degeneration. Third, a cell-intrinsic yet unknown function of munc18-1 is essential for prolonged survival.

Action Potentials↗
PubMed1994

Developing a medical informatics education program to support a statewide health information network.

The Florida Health Information Network (FHIN) was established in October 1989 to provide biomedical information services to the University of Florida Health Science Center (HSC) and to health professionals throughout the state--especially the northern thirty-nine counties of the state. FHIN services are available to all affiliates of the HSC and by annual subscription to nonaffiliates. At present, FHIN services include database access, circulation services, document delivery, and information services. Training network users has been an objective since the inception. Training has targeted both the HSC Library staff and HSC users and now is expanding to include remote users. Because many users have had insufficient experience with computers, the library has to teach the mechanics of access and network use and to instruct users regarding applications and database searching. This paper describes the development and implementation of the medical informatics education program. Topics include library staff training; educational offerings for HSC faculty, staff, and students; development and implementation of the remote training program; and organizational and budgetary implications for the construction of such a program.

Computer Communication Networks↗
PubMed2005

The privileging of communitarian ideas: citation practices and the translation of social capital into public health research.

The growing use of social science constructs in public health invites reflection on how public health researchers translate, that is, appropriate and reshape, constructs from the social sciences. To assess how 1 recently popular construct has been translated into public health research, we conducted a citation network and content analysis of public health articles on the topic of social capital. The analyses document empirically how public health researchers have privileged communitarian definitions of social capital and marginalized network definitions in their citation practices. Such practices limit the way public health researchers measure social capital's effects on health. The application of social science constructs requires that public health scholars be sensitive to how their own citation habits shape research and knowledge.

Health Services Research↗
PubMed2000

Global networking for assessment of impacts of global change on plant pests.

Global change encompasses changes in atmospheric composition, climate and climate variability, and land cover and land use. The occurrence of these changes and their interactive effects on biological systems are worldwide; thus, an effective global change research and impact assessment program must be based on international and interdisciplinary research and communication. With this in mind, several collaborative research networks with a focus on global change have been established in the biological sciences. They include the Global Change and Terrestrial Ecosystems (GCTE) Core Project of the International Geosphere-Biosphere Programme (IGBP) which aims to predict the effects of global change on terrestrial ecosystems, including agriculture and production forestry. Because of the importance of plant pests (arthropods, microbial pathogens, weeds) as yield-reducing factors in agriculture and as early indicators of global change, GCTE initiated a network Activity on "Global Change Impacts on Pests, Diseases and Weeds" with the overall goal of developing a predictive capability for impact assessment and adaptation. The network's specific objectives, contributing research projects, initial results and future challenges are discussed.

Journal Article↗
PubMedDate not supplied

Comparative evaluation of the use of artificial neural networks for modelling the epidemiology of schistosomiasis mansoni.

There has been a marked increase in the application of approaches based on artificial intelligence (AI) in the field of computer science and medical diagnosis, but AI is still relatively unused in epidemiological settings. In this study we report results of the application of neural networks (NN; a special category of AI) to schistosomiasis. It was possible to design an NN structure which can process and fit epidemiological data collected from 251 schoolchildren in Egypt using the first year's data to predict second and third years' infection rates. Data collected over 3 years included age, gender, exposure to canal water and agricultural activities, medical history and examination, and stool and urine parasitology. Schistosoma mansoni infection rates were 50%, 78% and 66% at the baseline and the 2 follow-up periods, respectively. NN modelling was based on the standard back-propagation algorithm, in which we built a suitable configuration of the network, using the first year's data, that optimized performance. It was implemented on an IBM compatible computer using commercially available software. The performance of the NN model in the first year compared favourably with logistic regression (NN sensitivity = 83% (95% confidence interval [CI] 78-88%) and positive predictive value (PPV) = 63% (95% CI 57-69%); logistic regression sensitivity = 66% (95% CI 60%-72%) and PPV = 59% (95% CI 53%-65%). The NN model generalized the criteria for predicting infection over time better than logistic regression and showed more stability over time, as it retained its sensitivity and specificity and had better false positive and negative profiles than logistic regression. The potential of NN-based models to analyse and predict wide-scale control programme data, which are inevitably based on unstable egg excretion rates and insensitive laboratory techniques, is promising but still untapped.

Adolescent↗
PubMed2004

The role of patients in designing health information systems: the case of applying simulation techniques to design an electronic patient record (EPR) interface.

One overall objective of Electronic Patient Records (EPRs) is to improve patient education and to enhance the patient experience through the use of information technology (IT) so as to facilitate the sharing of information between providers and their patients. The research project reported on herein took place at University Health Network (UHN) in Toronto (Canada), which is a large academic health science center with multiple hospital sites in the city. As a first step in this process, we examined the literature to investigate the human factors issues related to healthcare as well as other settings. Subsequently, we interviewed a number of interested stakeholders from two groups: the physicians (both family and attending) and the patients themselves. Finally, using a simulation environment, we explored the content that UHN lung-transplant patients would be interested in having within their own EPRs. In this paper, we report on the research, the methodology and the findings pertaining to the both the content and the design of an electronic patient record.

Canada↗
PubMed1996

N-tuple Regression Network.

N-tuple neural networks (NTNNs) have been successfully applied to both pattern recognition and function approximation tasks. Their main advantages include a single layer structure, capability of realizing highly non-linear mappings and simplicity of operation. In this work a modification of the basic network architecture is presented, which allows it to operate as a non-parametric kernel regression estimator. This type of network is inherently capable of approximating complex probability density functions (pdfs) and, in the limiting sense, deterministic arbitrary function mappings. At the same time, the regression network features a powerful one-pass training procedure and its learning is statistically consistent. The major advantage of utilizing the N-tuple architecture as a regression estimator is the fact that in this realization the training set points are stored by the network implicitly, rather than explicitly, and thus the operation speed remains constant and independent of the training set size. Therefore, the network performance can be guaranteed in practical implementations. Copyright 1996 Elsevier Science Ltd

Journal Article↗
PubMed2005

Neuropsychologic theory and findings in attention-deficit/hyperactivity disorder: the state of the field and salient challenges for the coming decade.

The past decade has witnessed the establishment of several now well-replicated findings in the neuropsychology of attention-deficit/hyperactivity disorder (ADHD), which have been confirmed by meta-analyses. Progress has been notable from the importing of cognitive science and neuroscience paradigms. Yet these findings point to many neural networks being involved in the syndrome and to modest effect sizes suggesting that any one neuropsychologic deficit will not be able to explain the disorder. In this article, leading theories and key findings are briefly reviewed in four key domains: attention, executive functions, state regulation and motivation, and temporal information processing. Key issues facing the field of neuropsychologic research and theory in ADHD include 1) the need for more integrative developmental accounts that address both multiple neural systems and the socialization processes that assure their development; 2) consideration of multiple models/measures in the same study so as to examine relative contributions, within-group heterogeneity, and differential deficit; and 3) better integration of cognitive process models with affective and temperament theories so that early precursors to ADHD can be better understood. Overall, the field has witnessed notable progress as it converges on an understanding of ADHD in relation to disruption of a multicomponent self-regulatory system. The next era must articulate multipathway, multilevel developmental accounts of ADHD that incorporate neuropsychologic effects.

Animals↗
PubMed2001

The Internet and clinical psychology: a general review of the implications.

The Internet has grown exponentially from its original conception and now takes the form of a vast network of interconnected computers. It encompasses such a wide arena within science that its impact cannot be ignored. This article reviews some of the areas where the Internet is relevant to Clinical Psychology. Three main areas identified and expanded upon are (i) use of the Internet as a communication medium within this domain, (ii) teaching of the discipline, and (iii) use of the Internet as a tool for psychological research. Within these three areas, examples of the applicability of the Internet are discussed as well as its limitations. In summary, use of the Internet within the psychological domain has many advantages and as such should be embraced by the clinical psychologist.

Communication↗
PubMed1997

Investigation of the CasCor Family of Learning Algorithms.

Six learning algorithms are investigated and compared empirically. All of them are based on variants of the candidate training idea of the Cascade Correlation method. The comparison was performed using 42 different datasets from the PROBEN1 benchmark collection. The results indicate: (1) for these problems it is slightly better not to cascade the hidden units; (2) error minimization candidate training is better than covariance maximization for regression problems but may be a little worse for classification problems; (3) for most learning tasks, considering validation set errors during the selection of the best candidate will not lead to improved networks, but for a few tasks it will. Copyright 1997 Elsevier Science Ltd.

Journal Article↗
PubMed2005

Measurement-induced entanglement for excitation stored in remote atomic ensembles.

A critical requirement for diverse applications in quantum information science is the capability to disseminate quantum resources over complex quantum networks. For example, the coherent distribution of entangled quantum states together with quantum memory (for storing the states) can enable scalable architectures for quantum computation, communication and metrology. Here we report observations of entanglement between two atomic ensembles located in distinct, spatially separated set-ups. Quantum interference in the detection of a photon emitted by one of the samples projects the otherwise independent ensembles into an entangled state with one joint excitation stored remotely in 10(5) atoms at each site. After a programmable delay, we confirm entanglement by mapping the state of the atoms to optical fields and measuring mutual coherences and photon statistics for these fields. We thereby determine a quantitative lower bound for the entanglement of the joint state of the ensembles. Our observations represent significant progress in the ability to distribute and store entangled quantum states.

Journal Article↗
PubMed2004

Laboratory, reading center, and coordinating center data management methods in the Jackson Heart Study.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death in the United States. In comparison to whites, African-Americans have a higher risk of dying from CVD and have a worse risk factor profile. The Jackson Heart Study (JHS) is designed to investigate the origin and natural history of CVD in African-Americans. METHODS: Reading centers for electrocardiograms, echocardiograms, carotid ultrasonograms, pulmonary function tests, and ambulatory blood pressure monitoring provide training for data accrual, quality assurance assessments, and specialized measurements for research objectives. Laboratories adhering to well-established quality assurance programs provide blood and urine analyses, as well as storage of specimens for future assays. A new Coordinating Center was created to perform functions analogous to those of coordinating centers for multisite studies, including protocol development, data management, statistical analyses, and operational support for the study. An established coordinating center serves as a resource to the JHS Coordinating Center, providing assistance in preparing procedure manuals and data collection forms. This group also designed and developed the JHS data management system. RESULTS: This network of specialized research organizations is implementing state- of-the-science methodologies to assess prevalence, progression, and incidence of CVD and subclinical atherosclerosis, and to evaluate a myriad of risk factors. From November 2000 through March 2004, JHS collected 4000 data fields on each of more than 5300 African-American participants. CONCLUSIONS: This article describes the roles of specialized research agencies contributing to JHS, and the methodologies being utilized to accumulate study data. A diverse collection of scientific disciplines is required to collect the information needed to meet the objectives of the JHS.

Arteriosclerosis↗
PubMed2005

Preferential urn model and nongrowing complex networks.

A preferential urn model, which is based on the concept "the rich get richer," is proposed. From a relationship between a nongrowing model for complex networks and the preferential urn model in regard to degree distributions, it is revealed that a fitness parameter in the nongrowing model is interpreted as an inverse local temperature in the preferential urn model. Furthermore, it is clarified that the preferential urn model with randomness generates a fat-tailed occupation distribution; the concept of the local temperature enables us to understand the fat-tailed occupation distribution intuitively. Since the preferential urn model is a simple stochastic model, it can be applied to research on not only the nongrowing complex networks, but also many other fields such as econophysics and social sciences.

Journal Article↗