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PubMed2002

Terminology-driven literature mining and knowledge acquisition in biomedicine.

In this paper we describe Tagged Information Management System (TIMS), an integrated knowledge management system for the domain of molecular biology and biomedicine, in which terminology-driven literature mining, knowledge acquisition (KA), knowledge integration (KI), and XML-based knowledge retrieval are combined using tag information management and ontology inference. The system integrates automatic terminology acquisition, term variation management, hierarchical term clustering, tag-based information extraction (IE), and ontology-based query expansion. TIMS supports introducing and combining different types of tags (linguistic and domain-specific, manual and automatic). Tag-based interval operations and a query language are introduced in order to facilitate KA and retrieval from XML documents. Through KA examples, we illustrate the way in which literature mining techniques can be utilised for knowledge discovery from documents.

Artificial Intelligence↗
PubMed1999

Discourse structures in medical reports--watch out! The generation of referentially coherent and valid text knowledge bases in the MEDSYNDIKATE system.

The automatic analysis of medical narratives currently suffers from neglecting text structure phenomena such as referential relations between discourse units. This has unwarranted effects on the descriptional adequacy of medical knowledge bases automatically generated from texts. The resulting representation bias can be characterized in terms of incomplete, artificially fragmented and referentially invalid knowledge structures. We focus here on four basic types of textual reference relations, viz. pronominal and nominal anaphora, textual ellipsis and metonymy and show how to deal with them in an adequate text parsing device. Since the types of reference relations we discuss show an increasing dependence on conceptual background knowledge, we stress the need for formally grounded, expressive conceptual representation systems for medical knowledge. Our suggestions are based on experience with MEDSYNDIKATE, a medical text knowledge acquisition system designed to properly deal with various sorts of discourse structure phenomena.

Artificial Intelligence↗
PubMedDate not supplied

Comparison of knowledge-based and distance geometry approaches for generation of molecular conformations.

A knowledge-based approach for generating conformations of molecules has been developed. The method described here provides a good sampling of the molecule's conformational space by restricting the generated conformations to those consistent with the reference database. The present approach, internally named et for enumerate torsions, differs from previous database-mining approaches by employing a library of much larger substructures while treating open chains, rings, and combinations of chains and rings in the same manner. In addition to knowledge in the form of observed torsion angles, some knowledge from the medicinal chemist is captured in the form of which substructures are identified. The knowledge-based approach is compared to Blaney et al.'s distance geometry (DG) algorithm for sampling the conformational space of molecules. The structures of 113 protein-bound molecules, determined by X-ray crystallography, were used to compare the methods. The present knowledge-based approach (i) generates conformations closer to the experimentally determined conformation, (ii) generates them sooner, and (iii) is significantly faster than the DG method.

Algorithms↗
PubMed1997

Increasing physician involvement In cholesterol-lowering practices: The role of knowledge, attitudes and perceptions.

The study evaluated a multifaceted educational intervention systematically designed to increase physician involvement in cholesterol-lowering practices. We hypothesized that knowledge, perceptions and behaviours would be enhanced in participating physicians, compared with controls. Method: Fifty-one family physicians were assigned randomly to three groups; the two experimental groups attended a training workshop, received physician and patient education materials and ongoing consultant support. One experimental group also received a "cuing" intervention. The control group received no interventions. Outcome measures included knowledge and attitude scores, self-efficacy perceptions, and physician dietary counselling behaviour. Measures were taken at pretest, 6 weeks and 15 months later. Results: Intervention group physicians achieved significantly higher knowledge scores than the control group at the six-week test; the differences disappeared at 15 months. Attitudes, self-reported practices and overall self-efficacy scores were similar across groups. Within group variation was highly significant. Physician dietary counselling scores were significantly higher in the intervention groups (p = 0.0001). Some associations were seen among knowledge, attitude, self-efficacy and dietary counselling scores. Conclusion: Physician behaviour change in cholesterol reduction may not depend entirely upon knowledge, attitudes and perceptions.

Journal Article↗
PubMed2001

Impact of a 10-year nation-wide alcohol campaign on knowledge of sensible drinking limits in Denmark.

In Great Britain and in Denmark, strong efforts have been made to influence knowledge on upper threshold for hazardous drinking. In Denmark, a campaign has been repeated every week 40 from 1990 to 2000 with information on the sensible drinking limits of 21 drinks per week for men and 14 drinks per week for women. The aim of this study was to examine the effect of this ongoing campaign on the level of knowledge of sensible drinking limits for men and women. Random representative samples of 1030 adult Danes were telephone interviewed each year during 1994-1999. Our main finding was that the level of knowledge of sensible drinking limits for own sex increased in all subsets of the population throughout the period. However, at the end of the study period (1999) a total of 80% of highly educated young (18-25 years) men knew sensible drinking limits for own sex, while only 35% of uneducated older (more than 65 years) men had knowledge on sensible drinking limits. The proportions were similar among women. Subjects admitting an intake higher than sensible for own sex, i.e. 21 and 14 drinks per week, respectively, had the highest knowledge of these drinking limits. We conclude that public health campaigns, such as the sensible drinking limit campaign, certainly has an impact on level of awareness in the general population. Furthermore, those drinking more than 21 and 14 drinks per week, respectively, are reached by these campaigns.

Adult↗
PubMed2002

AIDS knowledge among Latinos: the roles of language, culture, and socioeconomic status.

AIDS has a disproportionate effect on persons of Latino origin, who have lower knowledge of AIDS than other ethnic groups. This study assessed AIDS knowledge among Latino adults in New Jersey according to acculturation and socioeconomic status. Data on 121 Latino adults were collected in spring 2000 using bilingual telephone interviews. Respondents were selected using the Census' Latino surname methodology. Items were adapted from the National Health Interview Survey Supplement on AIDS Knowledge and Attitudes and the Marin acculturation scale. AIDS knowledge was more strongly associated with language exposure than with self-assessed English or Spanish language abilities. Low educational attainment and bilingual language exposure were associated with lower AIDS knowledge; when other factors were controlled, place of schooling, length of time in the United States, age and gender were not statistically significant. Transmission of HIV via casual contact was widely misunderstood, but general facts about AIDS and likely means of HIV transmission were well known. AIDS education materials should be designed in both English and Spanish and should take into account the lower educational attainment of recent Latino immigrants.

Journal Article↗
PubMed2001

Psychiatrists' knowledge and attitudes about costs of commonly prescribed treatments in psychiatry.

A survey was conducted to assess psychiatrists' knowledge and attitudes regarding the costs of various psychiatric treatments. Psychiatrists (n = 500) were randomly selected from the membership of the Ohio Psychiatric Association. The survey explored several aspects of psychiatrists' knowledge of costs, including estimated prices of 24 specific psychiatric treatments (frequently used psychotropic medications, laboratory tests, and inpatient and outpatient procedures) as well as their level of confidence in their estimates. The survey also asked a series of attitude/opinion questions and specific demographic data. The psychiatrists (n = 265, 59% response) perceived that knowing the costs of treatments was an important consideration when choosing a particular treatment. Psychiatrists' actual knowledge of the costs of treatment was inconsistent with their beliefs of the importance of knowing the costs as well as their reported confidence in their knowledge of costs. Information about the costs of psychiatric treatments is an important clinical consideration and a program to improve clinicians' knowledge of the costs of psychiatric treatment could occur during residency training.

Adult↗
PubMed2006

Wayfinding behavior and spatial knowledge of adults and children in a virtual environment: The role of landmarks.

This study investigated the effect of different organizations of landmark-location pairings as fine-space information on wayfinding behavior and spatial knowledge on a total of 90 participants: 30 second graders, 30 sixth graders, and 30 adults. All participants had to find their way to a goal in a virtual environment with either randomized or categorical landmarks, or without any landmarks. Thereafter, they had to find the shortest way from the start position to the goal in two consecutive trials (wayfinding performance), and they had to solve a number of spatial knowledge tasks. The results showed that independent of their categorical function, the existence of landmarks influenced the way-finding performance of adults and children in the same way. Whereas the presence of landmarks had no effect on spatial survey knowledge, landmark knowledge itself was influenced by the categorical function of the landmarks presented. Moreover, second graders showed limited achievement compared to adults independent of the existence of landmarks. The main results implicate firstly that children at school age indeed are able to use landmark-location pairings as fine-space information like adults during learning an unknown environmental space, and secondly that a dissociation between wayfinding behavior and spatial knowledge might exist.

Adult↗
PubMed2000

Knowledge and opinions about organ donation among urban high school students: pilot test of a health education program.

BACKGROUND: Increasing the diversity of the organ donor pool might improve the opportunities for people of color on organ transplant waiting lists to receive donated organs. We report on the results of a pilot classroom health education program to improve knowledge about organ donation and transplantation among a diverse student body at an urban high school. METHODS: The effectiveness of the educational program was evaluated with baseline and follow-up questionnaires which examined: 1) whether the program increased knowledge about organ donation; 2) whether the students' opinions about organ donation changed; and 3) whether the program was related to any changes in opinion. RESULTS: On the follow-up questionnaire, correct answers on 15 factual questions increased by 18% for the treatment group, compared to 5% for the control group (p = 0.00). Regarding opinions, at baseline 92% of white students had positive opinions about donation, compared to 48% of the students of color (p = 0.00). In the follow-up survey, the increase in positive opinions among the students of color was significantly greater than among white students (p = 0.04). In this pilot study, however, changes in opinions occurred with equal frequency among students in the treatment and control groups. In regression analysis, both knowledge of the subject and discussing donation with one's family were significantly associated with positive opinions about donation. CONCLUSIONS: Overall, this pilot study provided encouraging evidence that the classroom health education program affected knowledge about organ donation, and that opinions about organ donation are responsive to increases in knowledge.

Adolescent↗
PubMed2000

The use of category and exemplar knowledge in the solution of anchoring tasks.

Five studies examine the role that category and exemplar knowledge play in the mediation of anchoring effects--the assimilation of an absolute estimate to a previously considered standard. Studies 1 through 3 demonstrate that comparing the target object with a plausible anchor (i.e., a standard that constitutes a possible value for the target) leads to a selective increase in the accessibility of anchor-consistent exemplar knowledge about the target. This easily accessible knowledge is then used to generate the absolute estimate, which leads to its assimilation to the standard. Studies 4 and 5 demonstrate that comparing the target with an implausible anchor, however, involves the activation of knowledge about the general category of the target, rather than exemplar knowledge about the target itself.

Adult↗
PubMed1994

Models of the effects of prior knowledge on category learning.

When people learn about a new category, they are influenced by prior knowledge of other categories. In 5 experiments, subjects made categorization judgments after observing descriptions of persons from a location referred to as City W. In these experiments, prior knowledge as well as observations within City W were manipulated. The integration, weighting, and distortion models of categorization explain prior knowledge effects in different ways. The integration model, which assumes that categorization is influenced by prior examples from other categories, predicted the results of the experiments. It was found that the effect of prior knowledge was independent of the observed proportion of category membership in City W, that the prior knowledge effect was diminished with more observations, and that learning about City W affected subjects' judgments about the general population. The weighting and distortion models could not account for all of the results.

Humans↗
PubMed2004

Evidence-based and intuition-based self-knowledge: an FMRI study.

Behavioral and neuropsychological studies have suggested multiple self-knowledge systems may exist (i.e., evidence-based and intuition-based self-knowledge); however, little is known about the nature of intuition-based self-knowledge. In a functional magnetic resonance imaging study, the neural correlates of intuition-based and evidence-based self-knowledge were investigated. Participants with high and low experience in different domains (soccer and acting) made self-descriptiveness judgments about words from each domain while being scanned. High-experience domain judgments produced activation in a network of neural structures called the X-system, involved in automatic social cognition, whereas low-experience domain judgments produced activations in a network called the C-system, involved in effortful social cognition and propositional thought. The affective and slow-changing nature of intuition-based self-knowledge is discussed.

Adult↗
PubMed2005

Metacognition, risk behavior, and risk outcomes: the role of perceived intelligence and perceived knowledge.

The present study explores 2 key variables in social metacognition: perceived intelligence and perceived levels of knowledge about a specific content domain. The former represents a judgment of one's knowledge at an abstract level, whereas the latter represents a judgment of one's knowledge in a specific content domain. Data from interviews of approximately 8,411 female adolescents from a national sample were analyzed in a 2-wave panel design with a year between assessments. Higher levels of perceived intelligence at Wave 1 were associated with a lower probability of the occurrence of a pregnancy over the ensuing year independent of actual IQ, self-esteem, and academic aspirations. Higher levels of perceived knowledge about the accurate use of birth control were associated with a higher probability of the occurrence of a pregnancy independent of actual knowledge about accurate use, perceived intelligence, self-esteem, and academic aspirations.

Achievement↗
PubMed1994

Absence of knowledge attribution and self-recognition in young chimpanzees (Pan troglodytes).

Mirror self-recognition in chimpanzees (Pan troglodytes) is typically delayed until 4 1/2-8 years of age. Also, species capable of mirror self-recognition may be capable of some forms of mental state attribution related to intentions and knowledge. Previous investigations of knowledge attribution by chimpanzees used adolescents and adults but did not explicitly test for self-recognition. We report an investigation of knowledge attribution in 6 young chimpanzees previously tested for self-recognition. Subjects were required to discriminate between a person who had seen where food was hidden and another person who had not. The results are consistent with the proposition that most chimpanzees younger than 4 1/2 years of age show neither mirror self-recognition nor knowledge attribution. The results are also consistent with the idea that, just as in humans, development of self-recognition in chimpanzees may precede development of knowledge attribution.

Aging↗
PubMed2004

Mothers' and fathers' knowledge of adolescents' daily activities: its sources and its links with adolescent adjustment.

To elucidate the benefits ascribed to parental monitoring, the authors examined links between parental knowledge and methods of obtaining knowledge about adolescents' activities, and links between these constructs and adolescent adjustment. The roles of parent gender, adolescent gender, and family earner status in these associations were also studied. Participants were 95 adolescents (ages 10 to 17 years, 60% male and 40% female) and their parents. Mothers knew more about adolescents' activities than did fathers and were more likely than fathers to gain information by active supervision or voluntary disclosure from the adolescent. Fathers, more than mothers, received information via spouses. Active methods of supervision predicted more knowledge among fathers and mothers from dual-earner families but not among mothers from single-earner families. More maternal knowledge predicted lower adolescent deviance. No method of gaining knowledge predicted adjustment directly.

Adaptation, Psychological↗
PubMed2006

Exploring the neural organization of person-related knowledge: lateralization of lesion, category specificity, and stimulus modality effects.

While it is generally agreed that the right fusiform gyrus is specialized for face recognition, the question of whether knowledge about persons is lateralized in the temporal lobes is more contentious. Does knowledge about people differ from other kinds of object knowledge with respect to brain laterality? Are side-of-lesion effects mediated by stimulus modality? This study aimed to investigate these questions by comparing patients with left temporal (LT) (n=8) and right temporal (RT) (n=11) lesions to control subjects (n=12) on verbal and visual tests of people, buildings, and objects. The RT group was impaired at recognizing famous faces, but not at choosing the picture of a famous building or a famous name from nonfamous distracters. The LT group was impaired at naming people, buildings, and objects, regardless of stimulus modality. When presemantic processing was controlled for, neither patient group was impaired in producing person-specific knowledge to faces or names, supporting the notion that semantic knowledge for people as for other kinds of objects, is stored in a distributed network across both hemispheres, regardless of stimulus modality.

Adult↗
PubMed2006

Physician decision making and cardiac risk: effects of knowledge, risk perception, risk tolerance, and fuzzy processing.

Despite training, professionals sometimes make serious errors in risky decision making. The authors investigated judgments and decisions for 9 hypothetical patients at 3 levels of cardiac risk, comparing student and physician groups varying in domain-specific knowledge. Decisions were examined regarding whether they deviated from guidelines, how risk perceptions and risk tolerances determined decisions, and how the latter differed for knowledge groups. More knowledgeable professionals were better at discriminating levels of risk according to external correspondence criteria but committed similar errors in disjunctive probability judgments, violating internal coherence criteria. Also, higher knowledge groups relied on fewer dimensions of information than did lower knowledge groups. Consistent with fuzzy-trace theory, experts achieved better discrimination by processing less information and made sharper all-or-none distinctions among decision categories.

Adult↗
PubMed1993

Writing quality, reading skills, and domain knowledge as factors in text comprehension.

Subjects listened to and recalled three passages. Each subject was also given a general reading comprehension test. The passages were presented either in such a way that subjects could use their general knowledge to help understand them, or in such a way that no specific world knowledge seemed applicable. This was achieved by giving the passages a helpful title, versus no title or an unhelpful title. The passages were written in two different versions, preserving their content but varying their style. In one version, the language was as helpful as we could make it in signalling to the listener discourse importance, while in the other version the language was as unhelpful as we could make it while still writing an English text. All three factors--domain knowledge, writing style, and skill--significantly affected reproductive recall, and there were no interactions between these factors. However, while good writing was sufficient to improve the reproduction of the texts, an analysis of the recall elaborations subjects made revealed that the correctness of their elaborations depended strongly on the availability of appropriate domain knowledge. Thus, good writing and domain knowledge are not simply substitutable, but affect comprehension in somewhat different ways.

Adult↗