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PubMed2003

Using improved neural network model to analyze RSP, NOx and NO2 levels in urban air in Mong Kok, Hong Kong.

As the health impact of air pollutants existing in ambient addresses much attention in recent years, forecasting of air pollutant parameters becomes an important and popular topic in environmental science. Airborne pollution is a serious, and will be a major problem in Hong Kong within the next few years. In Hong Kong, Respirable Suspended Particulate (RSP) and Nitrogen Oxides NOx and NO2 are major air pollutants due to the dominant diesel fuel usage by public transportation and heavy vehicles. Hence, the investigation and prediction of the influence and the tendency of these pollutants are of significance to public and the city image. The multi-layer perceptron (MLP) neural network is regarded as a reliable and cost-effective method to achieve such tasks. The works presented here involve developing an improved neural network model, which combines the principal component analysis (PCA) technique and the radial basis function (RBF) network, and forecasting the pollutant levels and tendencies based in the recorded data. In the study, the PCA is firstly used to reduce and orthogonalize the original input variables (data), these treated variables are then used as new input vectors in RBF neural network model established for forecasting the pollutant tendencies. Comparing with the general neural network models, the proposed model possesses simpler network architecture, faster training speed, and more satisfactory predicting performance. This improved model is evaluated by using hourly time series of RSP, NOx and NO2 concentrations collected at Mong Kok Roadside Gaseous Monitory Station in Hong Kong during the year 2000. By comparing the predicted RSP. NOx and NO2 concentrations with the actual data of these pollutants recorded at the monitory station, the effectiveness of the proposed model has been proven. Therefore, in authors' opinion, the model presented in the paper is a potential tool in forecasting air quality parameters and has advantages over the traditional neural network methods.

Air Pollutants↗

PubMed2005

Modeling and optimization of high-sensitivity, low-volume microfluidic-based surface immunoassays.

Microfluidics are emerging as a promising technology for miniaturizing biological assays for applications in diagnostics and research in life sciences because they enable the parallel analysis of multiple analytes with economy of samples and in short time. We have previously developed microfluidic networks for surface immunoassays where antibodies that are immobilized on one wall of a microchannel capture analytes flowing in the microchannel. This technology is capable of detecting analytes with picomolar sensitivity and from sub-microliter volume of sample within 45 min. This paper presents the theoretical modeling of these immunoassays where a finite difference algorithm is applied to delineate the role of the transport of analyte molecules in the microchannel (convection and diffusion), the kinetics of binding between the analyte and the capture antibodies, and the surface density of the capture antibody on the assay. The model shows that assays can be greatly optimized by varying the flow velocity of the solution of analyte in the microchannels. The model also shows how much the analyte-antibody binding constant and the surface density of the capture antibodies influence the performance of the assay. We then derive strategies to optimize assays toward maximal sensitivity, minimal sample volume requirement or fast performance, which we think will allow further development of microfluidic networks for immunoassay applications.

Antigen-Antibody Complex↗

PubMed2003

[A typology for nursing processes exemplified by the "Nursing Process, Standardization and Quality in the Nursing Care Sector" Project].

This paper is based on the project "nursing process, standardisation and quality in nursing care" which is funded by the BMBF. This venture aims to develop and constitute a structure for recordation and documentation of nursing processes in terms of a typology and to standardise patients data for an exchange. The typology results from both the outcomes of the actual analysis of 128 patients in hospitals, homes for the elderly and community health care centers and the research on nursing classifications. The contents of the typology has been developed in co-operation with nurses working in such institutions. The structure and transfer of the data set will be realised by an IT media based network. The range of the project is regional, national and international. In this project the Bremen Institute of Industrial Technology and Applied Work Science (BIBA-ATOP) was responsible for the project management and the development of the IT based structure of the typology. The contents of the typology have been developed by the Institute of Applied Nursing Research (iap).

Documentation↗

PubMed2000

Inflammation in cystic fibrosis and its management.

Pulmonary complications are by far the most serious complications in cystic fibrosis (CF). In response to endobronchial bacterial infections, the long-term consequences of chronically activated polymorphonuclear leukocytes (neutrophils) are thought to cause loss of lung function and premature death. Effective anti-inflammatory therapy implies that we understand the complex networks of the immune response with its myriads of mediators on effector cells. We have many steps to go in this context, but science has already shed some light on inflammatory mechanisms in CF airways, and anti-inflammatory treatment strategies have been applied clinically with some success. The aim of this chapter is to review our present knowledge, and we will focus on early inflammation, bacterial persistence mechanisms, neutrophil activation, cytokines and nitric oxide together with anti-inflammatory treatment strategies in CF patients.

Animals↗

PubMed2006

Ensemble classifier for protein fold pattern recognition.

MOTIVATION: Prediction of protein folding patterns is one level deeper than that of protein structural classes, and hence is much more complicated and difficult. To deal with such a challenging problem, the ensemble classifier was introduced. It was formed by a set of basic classifiers, with each trained in different parameter systems, such as predicted secondary structure, hydrophobicity, van der Waals volume, polarity, polarizability, as well as different dimensions of pseudo-amino acid composition, which were extracted from a training dataset. The operation engine for the constituent individual classifiers was OET-KNN (optimized evidence-theoretic k-nearest neighbors) rule. Their outcomes were combined through a weighted voting to give a final determination for classifying a query protein. The recognition was to find the true fold among the 27 possible patterns. RESULTS: The overall success rate thus obtained was 62% for a testing dataset where most of the proteins have <25% sequence identity with the proteins used in training the classifier. Such a rate is 6-21% higher than the corresponding rates obtained by various existing NN (neural networks) and SVM (support vector machines) approaches, implying that the ensemble classifier is very promising and might become a useful vehicle in protein science, as well as proteomics and bioinformatics. AVAILABILITY: The ensemble classifier, called PFP-Pred, is available as a web-server at http://202.120.37.186/bioinf/fold/PFP-Pred.htm for public usage.

Algorithms↗

PubMed2001

Tobacco industry efforts at discrediting scientific knowledge of environmental tobacco smoke: a review of internal industry documents.

STUDY OBJECTIVE: Using tobacco industry internal documents to investigate the use of tobacco industry consulting scientists to discredit scientific knowledge of environmental tobacco smoke (ETS). DESIGN: Basic and advanced searches were performed on the Philip Morris, Tobacco Institute, R J Reynolds, Brown and Williamson, Lorillard, and the Council for Tobacco Research document web sites, with a concentration on the years 1985-1995. Guildford depository files located on the Canadian Council on Tobacco Control website were also searched. The documents were found in searches undertaken between 1 March and 30 June 2000. MAIN RESULTS: The industry built up networks of scientists sympathetic to its position that ETS is an insignificant health risk. Industry lawyers had a large role in determining what science would be pursued. The industry funded independent organisations to produce research that appeared separate from the industry and would boost its credibility. Industry organised symposiums were used to publish non-peer reviewed research. Unfavourable research conducted or proposed by industry scientists was prevented from becoming public. CONCLUSIONS: Industry documents illustrate a deliberate strategy to use scientific consultants to discredit the science on ETS.

Air Pollution, Indoor↗

PubMed1993

A biologically motivated associative memory architecture.

A synthesis of analytical techniques from the fields of biology, mathematics, computer science and engineering are used to model the information processing characteristics of the mammalian cerebellar cortex. By viewing anatomically different neurons as representing network elements whose input-output functions are different, a mechanism for distributing information throughout the memory is proposed. The functional circuitry developed to implement this feature is called the microcircuit. Overlapping microcircuit activity is used to describe the memory's read and write operations. Key features of the memory model include: (1) its use of a sparse interconnection network, (2) its ability to manipulate very large input patterns, (3) its distributed storage of input data patterns and (4) its statistical reconstruction of stored patterns during memory read operations. Quantitative measures for the memory's recall fidelity and storage capacity are derived and results of computer simulations are presented.

Animals↗

PubMed2025

Diversity of microtubule arrays in animal cells at a glance.

Microtubules are cytoskeletal filaments important for various cellular processes such as intracellular transport, cell division, polarization and migration. Microtubule organization goes hand in hand with cellular function. Motile cells, such as immune cells or fibroblasts, contain microtubule asters attached to the centrosome and the Golgi complex, whereas in many other differentiated cells, microtubules form linear arrays or meshworks anchored at membrane-bound organelles or the cell cortex. Over the past decade, new developments in cell culture, genome editing and microscopy have greatly advanced our understanding of complex microtubule arrays. In this Cell Science at a Glance article and the accompanying poster, we review the diversity of microtubule arrays in interphase animal cells. We describe microtubule network geometries present in various differentiated cells, explore the variety in microtubule-organizing centers responsible for these geometries, and discuss examples of microtubule reorganization in response to functional changes and their interplay with cell motility and tissue development.

Microtubules↗

PubMed2000

The space mission MIR'97: operational aspects.

BACKGROUND: A German astronaut visited the MIR space station between 10 February and 2 March 1997. Together with his Russian colleagues, he conducted a series of scientific investigations before, during and after his stay aboard the MIR station. Research performed during this flight was part of a global space life sciences programme and focused on metabolic homeostasis, fluid balance, calcium homeostasis and cardiovascular regulatory mechanisms. The main goal of the scientific experiments was to use this mission as a milestone to establish international networks of scientific collaboration using space research as a tool for focused research in respective fields. Thus, in most cases the results obtained from the astronaut complemented a series of results obtained on ground and from other flights. In other cases, they extended previous results and opened new fields for future research. PARTICIPANTS: Human space flight with astronauts serving as operators and at the same time as test subjects is very complex. Many people, including mission control, a science management team, medical operations, ethics committees and a medical board, participated to harmonize the different requirements, thus making a maximal scientific outcome possible. CONCLUSION: In summary, this space mission may be seen as a model for focused long-term multidisciplinary international research, and demonstrates that space medicine is no longer adventure but science.

Aerospace Medicine↗

PubMed1994

Psychiatry and the new dynamics.

Self-organizing and self-tuning neural networks are conceptualized as nonlinear dynamical systems. It is shown that biological psychiatry can be encompassed within this nonlinear dynamical framework, where it becomes coherent with trends in cognitive science. A state space representation that is a hyperspace with an energy topology and a fractal dimension is utilized. The state space representation provides a unifying framework for the classification of mental disorders. Clinical phenomena in schizophrenia can be explained in terms of nonlinear dynamics. The framework is also productive of psychiatric research. These results motivate the development of a nonlinear dynamical psychiatry.

Autistic Disorder↗

PubMed1980

Community medicine: the "first-born" of a marriage between medical education and medical care.

In Southern Israel, rapid development and industrialization have generated strains affecting both the population (ca. 0.5 million immigrants and ca. 50,000 Bedouin) and the medical care agencies (of the General Labour Federation and other Sick funds, the Health and other Ministries, etc.). In Beer-Sheva, the Center of Health Sciences (CHS) of the Ben-Gurion University of the Negev (BGUN) is the scene of a concerted effort to change the orientation of health care. The direction of change is away from the impersonal (the hospital and the disease) and towards that demanded by the public (the community and the person). It is being accomplished by fundamentally changing the education of health personnel. Change is being implemented and mediated by a coordinating consortium of in-region and BGUN care and/or welfare agencies, that plans and evaluates the process and progress of change for which each agency is responsible. Infrastructural innovation, somewhat hampered by the inertias of tradition, consists of making the university hospital effectively serve the regional network of hospital-affiliated, community-oriented primary care clinics. Curricular innovation, enthusiastically accepted and flourishing, uses the concept of "the natural history of disease" in basic-science and clinical teaching. Teaching takes place not only in the wards, but also in outpatient and primary care clinics, and in the facilities for occupational health, rehabilitation and public health.

Allied Health Personnel↗

PubMed1996

Fixing the leaky pipeline: women scientists in academia.

Although the number of women receiving doctorates and in academic positions has increased over the past 20 yr, females still are under-represented on university faculties. The extent of and reasons for this inequity are discussed. There are four critical periods that influence the retention of women in science: early childhood, adolescence, college, and the graduate school/job entry period. For each of the later three periods, the paper addresses the relationship between self-esteem and job performance, the quality and impacts of classroom interactions, and the role of the advisor/mentor. In addition, some of the difficulties in combining career and family responsibilities are considered. Effective networking and mentoring play an important role at the faculty level. If our goal is to have a scientific community open equally to all members of the general population, it is necessary to keep adolescent girls involved in math and science and to maintain their self-esteem. New faculty need to be more completely included in departmental and professional activities through both formal programs and good neighborliness on the behalf of existing faculty.

Animal Husbandry↗

PubMed2000

Web-based multimedia courseware for emergency cardiac patient management simulations.

This is a multidisciplinary inter-departmental/faculty project between the departments of computer science, electronic, communications and electrical engineering and nursing and paramedic sciences. The objective is to develop a web based multimedia front end to existing simulations of cardiac emergency scenaria. It will be used firstly in the teaching of nurses. The University of Hertfordshire is the only University in Britain using simulations of cardiac emergency scenaria for nurse and paramedic science education and therefore this project will add the multimedia dimension in distributed courses over the web and will assess the improvement in the educational process. The use of network and multimedia technologies, provide interactive learning, immediate feedback to students' responses, individually tailored instructions, objective testing and entertaining delivery. The end product of this project will serve as interactive material to enhance experiential learning for nursing students using the simulations of cardiac emergency scenaria. The emergency treatment simulations have been developed using VisSim and may be compiled as C code. The objective of the project is to provide a web based user friendly multimedia interface in order to demonstrate the way in which patients may be managed in critical situations by applying advanced technological equipment and drug administration. Then the user will be able to better appreciate the concepts involved by running the VisSim simulations. The evaluation group for the proposed software will be the Department of Nursing and Paramedic Sciences About 200 nurses use simulations every year for training purposes as part of their course requirements.

Allied Health Personnel↗

PubMed2000

A library-based bioinformatics services program.

Support for molecular biology researchers has been limited to traditional library resources and services in most academic health sciences libraries. The University of Washington Health Sciences Libraries have been providing specialized services to this user community since 1995. The library recruited a Ph.D. biologist to assess the molecular biological information needs of researchers and design strategies to enhance library resources and services. A survey of laboratory research groups identified areas of greatest need and led to the development of a three-pronged program: consultation, education, and resource development. Outcomes of this program include bioinformatics consultation services, library-based and graduate level courses, networking of sequence analysis tools, and a biological research Web site. Bioinformatics clients are drawn from diverse departments and include clinical researchers in need of tools that are not readily available outside of basic sciences laboratories. Evaluation and usage statistics indicate that researchers, regardless of departmental affiliation or position, require support to access molecular biology and genetics resources. Centralizing such services in the library is a natural synergy of interests and enhances the provision of traditional library resources. Successful implementation of a library-based bioinformatics program requires both subject-specific and library and information technology expertise.

Computational Biology↗

PubMed1995

Internet for teaching and learning introductory health informatics.

Internet resources seem attractive for teaching and learning. But are they usable and useful in their present form? We explored Internet, in particular its World Wide Web (WWW) resources, in a course on "Medical Methodology" (HINF270) for students of health information science. This course offers a systematic overview of the methodological principles of clinical care. Its broad scope and low depth makes this course a reasonable model to explore the limits of WWW resources. During the course, students wrote summaries of individual lectures. After critiquing and appropriate corrections, the texts were edited with Hypertext Mark-up Language (HTML) and augmented with links to WWW resources. Grading based on the papers, on their improvements through HTML and WWW, and on the provision of information on the search experience were incentives to use WWW. A formal questionnaire, administered on-line on a voluntary basis, concluded the investigation. Results show: 1) Even under considerable pressure to use WWW, libraries remain the reference source of choice for research; 2) Internet provides entertainment appeal even though practical utility is currently limited; 3) Technological proficiency with HTML and search engines is perceived as an asset; 4) Varying availability of Internet resources, uncertain and varying quality of sources, and limited specificity of research results are the major disadvantages of WWW. The teaching implications of these findings are discussed.

British Columbia↗

PubMed2005

The dawn of cognitive genetics? Crucial developmental caveats.

Attempts to bridge genetics and cognition are rapidly coming to the forefront of cognitive neuroscience. It is therefore crucial to evaluate the current state of knowledge about disorders of known genetic origin as a way of assessing whether, and if so how, links between genotype and cognitive phenotype can be drawn, however indirect these links might be. We review recent empirical findings from research on genetic disorders at three levels of description--cognitive, neural systems, and cellular--that caution against simple genotype-phenotype mappings at all levels. Most importantly, interdisciplinary efforts to integrate human genetics and cognition will need to operationalize the mechanisms driving both typical and atypical developmental processes over time.

Brain↗

PubMed2001

Joseph Hooker: the making of a botanist.

Joseph Hooker became one of the most influential botanists of his day. He is best remembered as a friend of Charles Darwin and an early advocate of natural selection. However, after returning to Britain from his first major voyage, Hooker spent years struggling to find a paid position that would allow him to pursue his studies of plant classification and distribution. As he worked to establish himself, he also helped transform the status of botany as a discipline. In all his efforts, Hooker relied on a network of unpaid, colonial collectors, whose often-forgotten contributions to Victorian natural history are vital to the understanding of the professionalization of the sciences in the 19th century.

Botany↗

PubMed1997

Pattern Categorization and Generalization with a Virtual Neuromolecular Architecture.

A multilevel neuromolecular computing architecture has been developed that provides a rich platform for evolutionary learning. The architecture comprises a network of neuron-like modules with internal dynamics modeled by cellular automata. The dynamics are motivated by the hypothesis that molecular processes operative in real neurons (in particular processes connected with second messenger signals and cytoskeleton-membrane interactions) subserve a signal integrating function. The objective is to create a repertoire of special purpose dynamic pattern processors through an evolutionary search algorithm and then to use memory manipulation algorithms to select combinations of processors from the repertoire that are capable of performing coherent pattern recognition/neurocontrol tasks. The system consists of two layers of cytoskeletally controlled (enzymatic) neurons and two layers of memory access neurons (called reference neurons) divided into a collection of functionally comparable subnets. Evolutionary learning can occur at the intraneuronal level through variations in the cytoskeletal structures responsible for the integration of signals in space and time, through variations in the location of elements that represent readin or readout proteins, and through variations in the connectivity of the neurons. The memory manipulation algorithms that orchestrate the repertoire of neuronal processors also use evolutionary search procedures. The network is capable of performing complicated pattern categorization tasks and of doing so in a manner that balances specificity and generalization. Copyright 1996 Elsevier Science Ltd.

Journal Article↗