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Results for “Large Language Models”

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At least 163 records · Page 9Linked to original sources

PubMed1997

Simulators in clinical surgery.

Simulators are no replacement for patients in surgical learning. Live patients are required for teaching clinical signs and skills. Large numbers of students, a relative lack of motivation, a decreasing number of common cases, unwilling patients, differences in language, etc., make clinical teaching in India a bitter problem. Because patient-related problems are important, surgical training using models can help students to gain effective control over surgical signs and skills.

Education, Medical, Undergraduate↗

PubMed1987

Trends in computational tools for biomagnetism: from procedural codes to intelligent scientific models.

The nature of the available computing tools strongly influences modern scientific investigations. The sources of well known problems associated with the use of procedural computer languages are traced and their consequences investigated. The likely impact of recent quantitative and qualitative advances in software and hardware is examined with emphasis on its relevance to the biomagnetic inverse problem. Gradual changes in the use of computers, some already employed in a recent study of a specific biomagnetic inverse problem, are outlined which take into account the large investment in conventional codes.

Animals↗

PubMed2026

Fast, accurate construction of multiple sequence alignments from protein language embeddings.

Multiple sequence alignment (MSA) is a foundational task in computational biology, underpinning protein structure prediction, evolutionary analysis, and domain annotation. Traditional MSA algorithms rely on pairwise amino acid substitution matrices derived from conserved protein families. While effective for aligning closely related sequences, these scoring schemes struggle in the low-identity "twilight zone." Here, we present a new approach for constructing MSAs leveraging amino acid embeddings generated by protein language models (PLMs), which capture rich evolutionary and contextual information from massive and diverse sequence datasets. We introduce a windowed reciprocal-weighted embedding similarity metric that is surprisingly effective in identifying corresponding amino acids across sequences. Building on this metric, we develop ARIES (Alignment via RecIprocal Embedding Similarity), an algorithm that constructs a PLM-generated template embedding and aligns each sequence to this template via dynamic time warping in order to build a global MSA. Across diverse benchmark datasets, ARIES achieves higher accuracies than existing state-of-the-art approaches, especially in low-identity regimes where traditional methods degrade, while scaling almost linearly with the number of sequences to be aligned. Together, these results provide the first large-scale demonstration of the power of PLMs for accurate and scalable MSA construction across protein families of varying sizes and levels of similarity, highlighting the potential of PLMs to transform comparative sequence analysis.

Deep Learning↗

PubMed2001

Age, consumer direction, and outcomes of supportive services at home.

PURPOSE: Supportive services at home are essential for older people with severe chronic impairments. Newer "consumer-directed" models of organizing home-based services rely heavily on service recipients rather than home care agencies to arrange and direct care at home. This study examined differences in service experience and outcomes between recipients over and under age 65 who direct their own services in one large Medicaid program. DESIGN AND METHODS: A random sample of 1,095 recipients of In-Home Supportive Services in California was selected and interviewed by telephone. Interviews were conducted in English, Spanish, and three Asian languages; those with severe cognitive impairment were excluded from the study. RESULTS: Findings indicate that although younger recipients embrace self-direction more enthusiastically than older ones, age differences are small on a majority of service outcomes. On average, older users embrace this model and manage within it much like younger users. Some differences emerge between the young-old (65-74) and old-old (75+), but these are neither consistent nor determinative. IMPLICATIONS: Old age is far from an inevitable barrier to self-direction. As with other age groups, there are opportunities and obstacles to be addressed as this newer approach to home care is disseminated.

Activities of Daily Living↗

PubMed1998

Modeling global and focal hyperarticulation during human-computer error resolution.

When resolving errors with interactive systems, people sometimes hyperarticulate--or adopt a clarified style of speech that has been associated with increased recognition errors. The primary goals of the present study were: (1) to provide a comprehensive analysis of acoustic, prosodic, and phonological adaptations to speech during human-computer error resolution after different types of recognition error; and (2) to examine changes in speech during both global and focal utterance repairs. A semi-automatic simulation method with a novel error-generation capability was used to compare speech immediately before and after system recognition errors. Matched original-repeat utterance pairs then were analyzed for type and magnitude of linguistic adaption during global and focal repairs. Results indicated that the primary hyperarticulate changes in speech following all error types were durational, with increases in number and length of pauses most noteworthy. Speech also was adapted toward a more deliberate and hyperclear articulatory style. During focal error repairs, large durational effects functioned together with pitch and amplitude to provide selective prominence marking of the repair region. These results corroborate and generalize the computer-elicited hyperarticulate adaptation model (CHAM). Implications are discussed for improved error handling in next-generation spoken language and multimodal systems.

Computers↗

PubMed1998

Exploring the ontology of surgical procedures in the Read Thesaurus.

The Read Thesaurus is a comprehensive user-led clinical vocabulary developed from earlier, and structurally simpler, versions of the Read Codes, with substantial input from United Kingdom health care professionals. A constituent template table underpins a range of functions, including semantic definition of concepts using object-attribute-value triples. Concept representation for surgical procedures has been investigated by a number of groups and a standard European structure has been proposed. Over 50% of the surgical procedures in the Read Thesaurus have been fully characterised using a number of attributes each with a defined concept field. We report progress to date and, based on our large-scale experience, examine the applicability of the European model to a user-defined terminology.

Europe↗

PubMed2003

Towards a broad-coverage biomedical ontology based on description logics.

We describe an ontology engineering methodology by which conceptual knowledge is extracted from an informal medical thesaurus (UMLS) and automatically converted into a formal description logics system (LOOM). Our approach consists of four steps: concept definitions are automatically generated from the UMLS, integrity checking of taxonomic and partonomic hierarchies is performed by LOOM's terminological classifier, cycles and inconsistencies are eliminated, as well as incremental refinement of the evolving knowledge base is performed by a domain expert. We report on experiments with a very large knowledge base composed of 164,000 concepts and 76,000 relations.

Artificial Intelligence↗

PubMed1996

A simulation model of the dynamics of HIV transmission in intravenous drug users.

The complex dynamics of HIV transmission and subsequent progression to AIDS make the use of traditional mathematical modeling techniques problematic. In a previous paper for this journal, Leslie and Brunham established the utility of a nonmathematical simulation language in modeling HIV transfer under conditions similar to those found among homosexual males. This study considers the application of such an approach in modeling HIV spread among intravenous drug users (IDUs) injecting within a "shooting gallery," a location providing a common needle supply to a large number of users. Modeling HIV transmission in this population involves not only consideration of heterogeneity in partnership selection, but also of the fact that spread of the virus is not directly from person to person, but via injection equipment. The General Purpose Simulation System was used to create a hypothetical cohort of IDUs, drawing from a common needle supply. Following introduction of an index case, the HIV infection rate in this cohort was followed over 5 simulated years. The model was then used to consider the effects of systematic variation in the frequency of injection and needle-cleaning behavior.

Acquired Immunodeficiency Syndrome↗

PubMed1993

Computer-based simulation model for evaluation of variations in practice patterns of general practitioners: a feasibility study.

Our study aimed at developing a computer-based simulation model for the consultation process in general practice. The model was developed in the computer language COM-CATS and makes use of an IBM-compatible personal computer with an automated diasprojector attached. A feasibility study comprised 122 general practitioners (108 male and 14 female), participating in the 6th Nordic Congress of General Practice (Aarhus, Denmark, 1989). All participants were given a short introduction to the patient and his symptoms, but all further information was optimal and selected by the doctor. There was a large variation in practice patterns of the general practitioners. Their actions were, however, performed selectively, i.e. a few tests were requested by most doctors and none of the doctors performed large numbers of tests. The great advantage of the computer-model in research into clinical decision-making is that it allows for a standardization of the clinical situation, gives the doctor an opportunity to select between optional information, and permits an automatic gathering of huge amounts of information about the decision-making process.

Computer Simulation↗

PubMed1995

Cultural variation in Africa: role of mechanisms of transmission and adaptation.

Cultural inheritance can be considered as a mechanism of adaptation made possible by communication, which has reached its greatest development in humans and can allow long-term conservation or rapid change of culturally transmissible traits depending on circumstances and needs. Conservativeness/flexibility is largely modulated by mechanisms of sociocultural transmission. An analysis was carried out by testing the fit of three models to 47 cultural traits (classified in six groups) in 277 African societies. Model A (demic diffusion) is conservation over generations, as shown by correlations of cultural traits with language, used as a measure of historical connection. Model B (environmental adaptation) is measured by correlation to the natural environment. Model C (cultural diffusion) is the spread to neighbors by social contact in an epidemic-like fashion and was tested by measuring the tightness of geographic clustering of the traits. Most traits examined, in particular those affecting family structure and kinship, showed great conservation over generations, as shown by the fit of model A. They are most probably transmitted by family members. This is in agreement with the theoretical demonstration that cultural transmission in the family (vertical) is the most conservative one. Some traits show environmental effects, indicating the importance of adaptation to physical environment. Only a few of the 47 traits showed tight geographic clustering indicating that their spread to nearest neighbors follows model C, as is usually the case for transmission among unrelated people (called horizontal transmission).

Journal Article↗

PubMed2000

Cumulative risk and early cognitive development: a comparison of statistical risk models.

Although it is generally accepted that social risk factors predict delays in early cognitive and language development, there is less agreement about how to represent such associations statistically. Using data collected prospectively on 87 African American children during their first 4 years, this study examined 3 analytic methods for describing a child's level of social risk: (a) individual risk variables, (b) factor scores derived from those risk variables, and (c) a risk index computed by tallying the number of risk conditions present. Comparisons indicated that the individual-risk-variables approach provides better overall prediction of developmental outcomes at a particular age but is less useful in predicting developmental patterns. The risk-factor approach provides good prediction of developmental trajectories when sample sizes are moderate to large. Finally, the risk-index approach is useful for relating social risk to developmental patterns when a large number of risk variables are assessed with a small sample or when other constructs are of primary interest.

Black or African American↗

PubMed1984

The influence of early malnutrition on subsequent behavioral development III. Learning disabilities as a sequel to malnutrition.

The academic performance of 129 Barbadian children (77 boys and 52 girls), who were 5-11-yr-old and suffered moderate to severe protein-energy malnutrition in the first year of life, was compared with the performance of matched comparisons, children who had no history of malnutrition. Children with a history of malnutrition were found to have lower performance on eight out of nine academic subject areas, namely, language arts, mathematics, general science, social science, reading, health, religion, and arts/crafts. Socioeconomic factors in the backgrounds of the children were also examined. A model is presented clarifying the interrelationships of malnutrition, socioeconomic status and school performance. Reduced school performance in the previously malnourished children can be largely accounted for by deficits in classroom behavior, and, to a lesser extent by a reduction in I.Q. Current socioeconomic status is not directly involved in altering academic performance whereas the early history of malnutrition and its accompanying conditions at the time of the illness are leading contributors to altered behavioral outcome and school performance.

Analysis of Variance↗

PubMed1995

Constraint satisfaction as a theory of sentence processing.

Various problems with the constraint satisfaction model are discussed. It is argued that the empirical evidence presented in support of the model does not concern predictions of the model that diverge from those of depth-first (one analysis at a time) models. Several methodological problems are also noted. As a theory of sentence processing, the model is inadequate. It fails to account for the assignment of local structure, global structure, structure involving discontinuous dependencies, long-distance dependencies, and adjunct phrases. It makes incorrect predictions about the timing of syntactic analysis. Further, because syntactic structure is available only through activation of syntactic projections stored in the lexical entry of words, the model leaves entirely unexplained the myriad psycholinguistic findings demonstrating independence of lexical and syntactic structure (in Event Related Potential studies, code-switching, pure syntactic priming, etc). Finally, the model is not restrictive or explanatory, providing an account that largely consists of post hoc correlations between frequency counts or subjects' ratings of sentences and processing time data for the same sentences.

Automatism↗

PubMed1991

Lack of a bimodal distribution of ventricular size in schizophrenia: a Gaussian mixture analysis of 1056 cases and controls.

The finding of clinical and laboratory differences between schizophrenic patients with large and small cerebral ventricles has led to the widespread assumption that large ventricles are a marker that characterizes a subgroup of patients with schizophrenia. We reviewed all published English language ventricle-to-brain ratio (VBR) studies in which individual data points were available (schizophrenics: n = 691, medical controls; n = 205, normal volunteers: n = 160). Using a univariate normal mixture model to examine the distribution of ventricular size in each group, we found no evidence of a mixture of Gaussian distributions (i.e., "bimodality") within any of the three groups. The same analysis was then performed on the combined sample of schizophrenic patients and normal and medical controls, respectively. In each case the improvement in fit of a mixture of normal distributions compared to a single component normal distribution was significant. The data do not support the notion that ventricular enlargement is a discontinuous marker of a subtype of schizophrenia.

Analysis of Variance↗

PubMed1991

Western State Hospital: implementing a MUMPS-based PC network.

Western State Hospital, a state-administered 1,200-bed mental health institution near Tacoma, Wash., confronted the challenge of automating its large campus through the application of the Healthcare Integrated Information System (HIIS). It is the first adaptation of the Veterans Administration's Decentralized Hospital Computer Program software in a mental health institution of this size, and the first DHCP application to be installed on a PC client/server network in a large U.S. hospital.

Hospital Bed Capacity, 500 and over↗

PubMed1990

Large-scale neurocognitive networks and distributed processing for attention, language, and memory.

Cognition and comportment are subserved by interconnected neural networks that allow high-level computational architectures including parallel distributed processing. Cognitive problems are not resolved by a sequential and hierarchical progression toward predetermined goals but instead by a simultaneous and interactive consideration of multiple possibilities and constraints until a satisfactory fit is achieved. The resultant texture of mental activity is characterized by almost infinite richness and flexibility. According to this model, complex behavior is mapped at the level of multifocal neural systems rather than specific anatomical sites, giving rise to brain-behavior relationships that are both localized and distributed. Each network contains anatomically addressed channels for transferring information content and chemically addressed pathways for modulating behavioral tone. This approach provides a blueprint for reexploring the neurological foundations of attention, language, memory, and frontal lobe function.

Animals↗

PubMed2002

Impact of genomics approaches on plant genetics and physiology.

Comprehensive analysis of genetic information in higher plants is under way for several plants of biological and agronomical importance. Among them, Arabidopsis thaliana, a member of Brassica family, and Oryza sativa(rice) have been chosen as model plants most suitable for genome analysis. Sequencing of the genome of A. thaliana was completed in December 2000, and rice genome sequencing is in progress. The accumulated genome sequences, together with the hundreds of thousands of ESTs from several tens of plant species, have drastically changed the strategy of plant genetics. By utilizing the information on the genome and gene structures, comprehensive approaches for genome-wide functional analysis of the genes, including transcriptome analysis using microarray systems and a comprehensive analysis of a large number of insertion mutant lines, have been widely adopted. As a consequence, a large quantity of information on both the structure and function of genes in these model plants has been accumulated. However, other plant species may have their own characteristics and advantages to study individual phenomena. Application of knowledge from the model plants to other plant species and vice versa through the common language, namely the genome information, should facilitate understanding of the genetic systems underlying a variety of biological phenomena. Introduction of this common language may not be very simple, especially in the case of complex pathways such as a process of cell-covering formation. Nevertheless, it should be emphasized that genomics approaches are the most promising way to understand these processes.

Journal Article↗

PubMed2003

Nervous system effects of occupational manganese exposure on South African manganese mineworkers.

Occupational exposure to airborne manganese dust has been shown to produce adverse effects on the central nervous system. Four hundred and eighty-nine blue and white collar manganese mineworkers from South Africa were studied cross-sectionally to investigate the nervous system effects of medium to low occupational manganese exposures. The different facilities included underground mines, surface processing plants, and office locations. A job exposure matrix was constructed using routine occupational hygiene data. Exposure variables included years of service, a cumulative exposure index (CEI) and average intensity of exposure (AINT) across all jobs, and blood manganese. Endpoints included items from the Q16, WHO-NCTB, SPES, and Luria-Nebraska test batteries, and a brief clinical examination. Potential confounders and effect modifiers included age, level of education, past medical history including previous head injury, previous neurotoxic job exposures, tobacco use, alcohol use and home language. Associations were evaluated by multiple linear and logistic regression modeling. Average exposure intensity across all jobs was 0.21mg/m(3) manganese dust. Multivariate analyses showed that none of the symptom nor test results were associated with any measure of exposure including blood manganese, after adjustment for confounders. This relatively large null study indicates that manganese miners exposed on average across all jobs to MnO(2) at levels near the American Conference of Governmental Industrial Hygienists Threshold Limit Value (ACGIH TLV) are unlikely to have a subclinical neurotoxicity problem.

Adult↗