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Results for “Knowledge base”

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PubMed1999

MDL and the statistical mechanics of protein potentials.

The combination of a wealth of structural data and impressive computational power provides detailed information pertaining to the structure and dynamics of biomacromolecules. A natural inclination is to incorporate this information into models to gain added predictive power on protein folding and stability. There has been considerable recent interest in developing "knowledge-based" potentials to describe internal interactions in proteins. In these approaches, probability distribution functions are inferred from existing knowledge. A common assumption has been the "quasi-chemical approximation" or "Boltzmann device". This method relates statistical mechanical probabilities to observed frequencies. The validity of this approach is discussed in detail from a statistical mechanics perspective. Because statistical mechanics is a form of statistical inference based on a lack of knowledge of the system, the "Boltzmann device" does not have a rigorous theoretical justification. In the present work, a statistical mechanics based on partial knowledge of the system is employed. This statistical mechanical scheme uses the minimum description length (MDL) of phase space as its main tool. With this approach, "knowledge-based" potentials can be derived in a rigorous fashion. In practical calculations, these potentials are best obtained using Bayesian inference methods similar to those used in image reconstruction.

Algorithms↗

PubMed1996

An integrated rule- and case-based approach to AIDS initial assessment.

The traditional approach to the development of knowledge-based systems (KBS) has been rule-based, where heuristic knowledge is encoded in a set of production rules. A rule-based reasoning (RBR) system needs a well constructed domain theory as its reasoning basis, and it does not make substantial use of the knowledge embedded in previous cases. An RBR system performs relatively well in a knowledge-rich application environment. Although its capability may be limited when previous experiences are not a good representation of the whole population, a case-based reasoning (CBR) system is capable of using past experiences as problem solving tools, therefore, it is appropriate for an experience-rich domain. In recent years, both RBR and CBR have emerged as important and complementary reasoning methodologies in artificial intelligence. For problem solving in AIDS intervention and prevention, it is useful to integrate RBR and CBR. In this paper, a hybrid KBS which integrates a deductive RBR system and an inductive CBR system is proposed to assess AIDS-risky behaviors.

Acquired Immunodeficiency Syndrome↗

PubMed1993

Concept mapping of movement-related knowledge.

Concept mapping was developed by Novak and Gowin in 1984 as a technique to examine an individual's knowledge-base in a given domain. In the motor domain, however, with a heavy emphasis on automated and tacit knowledge there may not be a base of information which can be verbally reported. 52 subjects with similar academic backgrounds were asked to explain all they knew about the concept of movement, and these reports were transcribed and assessed by four judges. Subjects also completed a pattern-recognition task related to procedural knowledge for movement. Over-all, the judges were able to identify a clear hierarchy in the levels of movement-related knowledge, suggesting that this technique may be useful in research on movement. However, this declarative knowledge appeared to be distinct from associated procedural knowledge, supporting Anderson's (1982) theory and the need for several tools to provide a more complete reflection of the knowledge base in a particular domain.

Acceleration↗

PubMed1991

Designing an outcome-oriented computer decision-support system for cardiovascular ICU--a preliminary report.

This paper describes the conceptual framework and preliminary results of an outcome-oriented decision-support system prototype for the cardiovascular intensive care unit (CVICU). The major characteristics of this design include: (1) its problem-based approach to solving clinical problems; (2) an integrated structure with the hospital information system in terms of its data, model and knowledge bases; (3) proposed alternative modes of interaction that include monitoring and critiquing; (4) and research modules that design, manage, and analyze outcome-based clinical studies. At present, an initial prototype has been implemented on a PC as a set of modules accessible from a main menu. The structural framework of the overall system is fairly well defined but only limited quantitative, statistical and expert knowledge has been captured. The second phase of the project involves porting the prototype to a Unix workstation environment, refining and adding models to the model base, expanding its knowledge bases, reasoning capability, and testing the prototype with actual clinical cases in a real-time fashion.

Alberta↗

PubMed1993

Graphical knowledge acquisition for medical diagnostic expert systems.

Like many textbook authors use text systems for writing their books, expert system authors should have easy to use knowledge acquisition systems for entering and testing their knowledge bases by themselves without much help from 'knowledge engineers'. In this paper, we report on a graphical knowledge acquisition tool (CLASSIKA) based on an expert system shell for heuristic classification (MED2) and designed for direct use by domain experts. We demonstrate how the system has been used for building a rather large expert system for diagnosing rheumatology diseases which is now being tested in clinical use.

Artificial Intelligence↗

PubMed1998

Quality criteria for electronic publications in medicine.

This paper defines "electronic publications in medicine (EPM)" as computer based training programs, databases, knowledge-based systems, multimedia applications and electronic books running on standard platforms and available by usual distribution channels. A detailed catalogue of quality criteria as a basis for development and evaluation of EPMs is presented. The necessity to raise the quality level of electronic publications is stressed considering aspects of domain knowledge, software engineering, media development, interface design and didactics.

Publishing↗

PubMed1996

Human errors in fatal and serious occupational accidents in Finland.

The aim of this study is to examine the effect of human error on industrial accidents. One hundred and seventy-eight fatalities and 99 serious accidents were classified according to Rasmussen's SRK model. Of accidents, 84-94% were due mainly to human error. Most of the errors were skill-based, next came rule-based errors and then knowledge-based errors. The type of error was analyzed by age, work experience and work tasks of the victims. The results showed that the SRK model is suitable for analyzing accidents in industrial work using rather simple technology.

Accidents, Occupational↗

PubMed1994

Major issues in user interface design for health professional workstations: summary and recommendations.

Lack of good user interfaces has been a major impediment to the acceptance and routine use of health-care professional workstations. Health-care providers, and the environment in which they practice, place strenuous demands on the interface. User interfaces must be designed with greater consideration of the requirements, cognitive capabilities, and limitations of the end-user. The challenge of gaining better acceptance and achieving widespread use of clinical information systems will be accentuated as the variety and complexity of multi-media presentation increases. Better understanding of issues related to cognitive processes involved in human-computer interactions is needed in order to design interfaces that are more intuitive and more acceptable to health-care professionals. Critical areas which deserve immediate attention include: improvement of pen-based technology, development of knowledge-based techniques that support contextual presentation, and development of new strategies and metrics to evaluate user interfaces. Only with deliberate attention to the user interface, can we improve the ways in which information technology contributes to the efficiency and effectiveness of health-care providers.

Cognition↗

PubMed2005

Software and expert system for the management of chronic hepatitis B.

Whereas the doubling time of overall biomedical knowledge bases has been estimated at about 19 years, the body of indexed information related to HBV has doubled in the last 8 years; the one related to HBV and antivirals has doubled in the last 5 years and the one related to Interferon and contraindications has doubled in less than 48 months. In Hepatology, as well as in other fast changing areas of medicine, the demand that clinical decision should always be based on the best verified knowledge available, is becoming more and more difficult to comply with. The Italian network of competence for hepatic diseases (Liver Unit Networks Association or LUNA) was established in 2003 with the patronage of the Italian Ministry of Health, with the primary goal of promoting advanced clinical research and real-time information exchange among the participating centres, facilitating knowledge sharing and identification of best practices. The ICT infrastructure designed for this purpose includes four sets of online accessible software tools:

Chronic Disease↗

PubMed1993

An international approach to master's-level preparation for clinical nurse specialists.

Nursing is seen as being increasingly a research-based profession with a developing knowledge base that demands a continuing programme of education. This is necessary to enable the practitioner to function with the level of expertise and skill required in today's health care systems. There have been repeated calls for and developments in the establishment of a higher-education approach to nursing, with degree courses for the advanced practitioner. It is also argued that in terms of the European perspective there are many commonalities in nursing and health care in Europe, and although cultural and national differences are important there can be advantages to nurses from different countries studying together. An example of a course which offers this European approach to higher education for nurses is described.

Congresses as Topic↗

PubMed1996

Biological sciences in Project 2000: an exploration of status.

Through Project 2000 preregistration nursing courses it was intended to establish a broad knowledge base for nurse education. This is likely to affect the way biological sciences are viewed as subjects within the curriculum. The aim of this study was to investigate the status of biological sciences in the curriculum following educational reform. A small-scale, descriptive study was undertaken investigating one institution. Quantitative and qualitative data were gathered using a postal questionnaire; this was complemented by contextual information obtained from documents. Findings indicated that there was a lack of consensus amongst teachers regarding what emphasis should be given to different subjects within the curriculum. It was commented that 'nursing' may have been displaced by pure subject disciplines, and that application of biological theory to practice was inadequate. Biological sciences, social sciences and behavioural sciences were allotted equal hours in the curriculum; concern was expressed, however, that there was insufficient time available for some subjects. This appeared to foster competition and tension, in particular between proponents of biological and social sciences. Teachers demonstrated subject loyalty, and promoted their own discipline within the curriculum. In an attempt to explain findings a conceptual framework based upon the sociology of knowledge and conflicts and tensions between groups within a profession was employed. Issues identified in the study suggest that there is cause for concern with respect to the structuring, teaching and learning of biological concepts, and their application to nursing practice.

Biological Science Disciplines↗

PubMed2006

From genomics to chemical genomics: new developments in KEGG.

The increasing amount of genomic and molecular information is the basis for understanding higher-order biological systems, such as the cell and the organism, and their interactions with the environment, as well as for medical, industrial and other practical applications. The KEGG resource (http://www.genome.jp/kegg/) provides a reference knowledge base for linking genomes to biological systems, categorized as building blocks in the genomic space (KEGG GENES) and the chemical space (KEGG LIGAND), and wiring diagrams of interaction networks and reaction networks (KEGG PATHWAY). A fourth component, KEGG BRITE, has been formally added to the KEGG suite of databases. This reflects our attempt to computerize functional interpretations as part of the pathway reconstruction process based on the hierarchically structured knowledge about the genomic, chemical and network spaces. In accordance with the new chemical genomics initiatives, the scope of KEGG LIGAND has been significantly expanded to cover both endogenous and exogenous molecules. Specifically, RPAIR contains curated chemical structure transformation patterns extracted from known enzymatic reactions, which would enable analysis of genome-environment interactions, such as the prediction of new reactions and new enzyme genes that would degrade new environmental compounds. Additionally, drug information is now stored separately and linked to new KEGG DRUG structure maps.

Biotransformation↗

PubMed2001

DIAN: a novel algorithm for genome ontological classification.

Faced with the determination of many completely sequenced genomes, computational biology is now faced with the challenge of interpreting the significance of these data sets. A multiplicity of data-related problems impedes this goal: Biological annotations associated with raw data are often not normalized, and the data themselves are often poorly interrelated and their interpretation unclear. All of these problems make interpretation of genomic databases increasingly difficult. With the current explosion of sequences now available from the human genome as well as from model organisms, the importance of sorting this vast amount of conceptually unstructured source data into a limited universe of genes, proteins, functions, structures, and pathways has become a bottleneck for the field. To address this problem, we have developed a method of interrelating data sources by applying a novel method of associating biological objects to ontologies. We have developed an intelligent knowledge-based algorithm, to support biological knowledge mapping, and, in particular, to facilitate the interpretation of genomic data. In this respect, the method makes it possible to inventory genomes by collapsing multiple types of annotations and normalizing them to various ontologies. By relying on a conceptual view of the genome, researchers can now easily navigate the human genome in a biologically intuitive, scientifically accurate manner.

Algorithms↗

PubMed2000

Feedback error learning neural network for trans-femoral prosthesis.

Feedback-error learning (FEL) neural network was developed for control of a powered trans-femoral prosthesis. Nonlinearities and time-variations of the dynamics of the plant, in addition to redundancy and dynamic uncertainty during the double support phase of walking, makes conventional control methods very difficult to use. Rule-based control, which uses a knowledge base determined by machine learning and finite automata method is limited since it does not respond well to perturbations and environmental changes. FEL can be regarded as a hybrid control, because it combines nonparametric identification with parametric modeling and control. This paper presents simulation of a powered trans-femoral prosthesis controlled by a FEL neural network. Results suggest that FEL can be used to identify inverse dynamics of an arbitrary trans-femoral prosthesis during simple single joint movements (e.g., sinusoidal oscillations). The identified inverse dynamics then allows the tracking of an arbitrary trajectory such as a desired walking pattern within a multijoint structure. Simulation shows that the identified controller responds correctly when the leg motion is exposed to a perturbation such as a frequent change of the ground reaction force or the hip joint torque generated by the user. FEL eliminates the need for precise, tedious, and complex identification of model parameters.

Activities of Daily Living↗

PubMed2003

The precautionary principle versus risk analysis.

Precautionary behavior serves a valuable protective purpose as a first response to the new. It causes a quick retreat to the safety of the familiar; it provides time for a realistic "friend or foe" assessment of a new event. This rational assessment is often delayed by the sluggishness of government bureaucratic processes, or stopped by an implied challenge to a status quo. At the public level, reassurance may be slow to overcome an early uncertainty. However, a precautionary response does not provide an operational governing principle, although it makes publicly plausible an indefinite concealment of de facto political actions, or nonaction. The alternative of rational decision making at the policy level should flow from a comparative benefit/cost/risk analysis. Such early risk analyses have pragmatic uncertainties based on the limited available knowledge base and, accordingly, require judgmental application.

Journal Article↗

PubMed1999

Improved phytonutrient content through plant genetic improvement.

During the twentieth century, plant breeding and genetics improved the nutritive value of horticultural and agronomic crops, particularly of macronutrients and fiber. Current research focuses more on micronutrients. Successful development of phytonutrient-enriched crop plants will be bolstered by interdisciplinary collaborative research, analytical and biotechnology advances, and public education. Although the melding of plant and nutrition research holds great promise, the genetic enhancement of crop plants for improved phytonutrient content will be challenging. This paper reviews the knowledge base on which genetic enhancement may be based, identifies gaps in scientific knowledge and technical capacities, and suggests a role for the federal government in research.

Agriculture↗

PubMedDate not supplied

Clinical decision support systems for the practice of evidence-based medicine.

BACKGROUND: The use of clinical decision support systems to facilitate the practice of evidence-based medicine promises to substantially improve health care quality. OBJECTIVE: To describe, on the basis of the proceedings of the Evidence and Decision Support track at the 2000 AMIA Spring Symposium, the research and policy challenges for capturing research and practice-based evidence in machine-interpretable repositories, and to present recommendations for accelerating the development and adoption of clinical decision support systems for evidence-based medicine. RESULTS: The recommendations fall into five broad areas--capture literature-based and practice-based evidence in machine--interpretable knowledge bases; develop maintainable technical and methodological foundations for computer-based decision support; evaluate the clinical effects and costs of clinical decision support systems and the ways clinical decision support systems affect and are affected by professional and organizational practices; identify and disseminate best practices for work flow-sensitive implementations of clinical decision support systems; and establish public policies that provide incentives for implementing clinical decision support systems to improve health care quality. CONCLUSIONS: Although the promise of clinical decision support system-facilitated evidence-based medicine is strong, substantial work remains to be done to realize the potential benefits.

Decision Support Systems, Clinical↗

PubMed1989

The MICROSTROKE expert system for stroke type diagnosis.

MICROSTROKE is a prototype expert system designed to categorize and diagnose stroke types based on clinical information. The knowledge base of MICROSTROKE includes information from large stroke registries. The system first queries the physician-user for details of the patient's history, information about the onset of stroke, accompanying symptoms, and pertinent neurologic findings and then sums the individual data items, factors in the a priori odds, and arrives at the probabilities of different stroke types for a given patient. Specific diagnosis of stroke type includes thrombosis, embolus, lacune, intracerebral hemorrhage, and subarachnoid hemorrhage. Stroke type diagnoses by MICROSTROKE were correct in 72.8% of 250 cases in the Hamburg Stroke Data Bank. MICROSTROKE runs on any MS-DOS microcomputer and is intended as a practical aid for physicians not fully familiar with the diagnosis of stroke types.

Cerebrovascular Disorders↗