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Alcohol and adolescents. Knowledge, attitudes, and behavior.

Students (n = 3017) from the 6th, 8th, 10th, and 12th grades in six school districts throughout Georgia and South Carolina completed a questionnaire to determine their knowledge, attitudes, and behavior regarding alcohol use. Results suggest that knowledge, attitudes, and behavior are significantly correlated. Two distinct attitudes were discovered: acceptable use of alcohol and unacceptable uses of alcohol, and these interacted with knowledge and behavior in different ways. Students who reported school as their major source of information about alcohol were more knowledgeable and had the most conservative attitudes toward unacceptable use of alcohol (p less than 0.001). White students scored higher on the knowledge test and had more liberal attitudes than minority students (p less than 0.001). Females were more conservative than males (p 0.001), and older students had more liberal attitudes (p less than 0.001). Our results suggest that efforts to educate youth about alcohol should incorporate acceptable uses as well as the negative aspects of drinking.

Adolescent↗

The assessment of diviners and their knowledge by civil servants in southwestern Nigeria.

Belief systems are continuously being modified through the interpretations individuals give to the cultural order. The present study investigates the evaluations which educated Nigerians have of diviners and their knowledge claims. Two hundred civil servants in Abeokuta, a state capital in the Southwestern region, were asked to assess diviners. It was discovered that diviners are believed to have access to supernatural knowledge and that this knowledge is seen as medically useful. Further development of the diviner's knowledge was endorsed by 70% of the sample. The respondents were however ambivalent towards diviners as persons or the bearers of the knowledge. They (diviners) are believed to have become unduly materialistic and prone to dubious activities. The implications of these findings for social change were then considered.

Adult↗

Priming of semantic autobiographical knowledge: a case study of retrograde amnesia.

The case of a 36-year-old man who suffers dense retrograde and anterograde amnesia as a result of closed-head injury that caused extensive damage to his left frontal-parietal and right parieto-occipital lobes is described. Patient K.C. has normal intelligence and relatively well-preserved perceptual, linguistic, short-term memory, and reasoning abilities. He possesses some fragmentary general knowledge about his autobiographical past, but he does not remember a single personal event or happening from any time of his life. He has some preserved expert knowledge related to the work he did for 3 years before the onset of amnesia, although he has no personal recollections from that period. Some features of K.C.'s retrograde amnesia can be interpreted in terms of the distinction between episodic and semantic memory, and in terms of the distinction between episodic and semantic autobiographical knowledge. K.C.'s semantic knowledge, but not his episodic knowledge, showed progressive improvement, or priming, in the course of the investigation.

Adult↗

Effects of two formats of informed consent on knowledge amongst persons with advanced HIV disease in a clinical trial of didanosine.

To determine subjects' perception of the purpose of informed consent, 113 subjects were recruited from a dose-controlled clinical trial of didanosine (ddI). Subjects were surveyed regarding how they made decisions regarding their medical care in general, about how they obtained information about this trial in particular, and several aspects of the informed consent procedure. Subjects were then randomly allocated to receive information about the trial by either a written only format or a written and verbal format 1 week before commencement of the trial. An eight-item instrument assessed knowledge of ddI prior to and subsequent to receiving information. Most subjects obtained information about HIV-related issues from their specialist (70%) or general (51%) medical practitioner. A large proportion of subjects (88%) reported that they believed their specialist medical practitioner always acted in their best interest. The majority of subjects (79%) believed that subjects should be allowed the choice between participating in the clinical trial and receiving the drug outside the trial mechanism. Of the subjects, 96% believed that informed consent was necessary in clinical trials; however, their opinions of the purpose of informed consent varied widely. Although they signed the informed consent, 44% of the subjects stated that they did not understand 'all' of the information that was provided. We found that the provision of information by written mode alone, or written and verbal modes were both associated with significant increases in knowledge levels and that there was a significant interaction in the degree of change between the two methods, with the written plus verbal method showing the most improvement over time. There was an interaction between degree of improvement in knowledge of didanosine in subjects who received written information versus those who received written and verbal knowledge and time (pre- versus post-consent) and a significant main effect for time. All subjects were relatively well-informed about the drug and stated that specialist and general medical practitioners were their major source of knowledge for all aspects of their HIV health care.

Adult↗

Level of cancer pain knowledge among baccalaureate student nurses.

Inadequate nursing education is a major impediment to effective pain relief for cancer patients throughout the world. This study was conducted to identify the level of cancer pain knowledge among baccalaureate student nurses and to determine whether specific activities affect this level of knowledge. Two questionnaires were administered to 82 baccalaureate student nurses in the final course of their program. Although the students displayed a realistic perspective about the severity and prevalence of cancer pain and psychological dependence, specific knowledge deficits and negative attitudes suggest the possibility of inadequate pain management. Specifically, the students believed that (a) maximal analgesic therapy should be delayed until the patient's prognosis was less than 12 months; (b) the proportion of patients whose pain can be controlled by appropriate therapy is less than is possible; (c) increasing pain is related to tolerance rather than to progression of the disease; (d) the preferred route of administration is intravenous rather than oral; and (e) the degree of respiratory depression, rather than constipation, does not decrease with repeated administration. Significant positive correlations (P < or = 0.05) were found between age and cancer pain knowledge and between attendance at seminars/workshops and time spent reading professional journal articles. Of the 30% of the participants who perceived a particular person to be a source for obtaining information about cancer pain management, 52% specified a practicing registered nurse. Seminars and workshops were chosen by 59% of the students as the most effective way for nurses to increase their knowledge.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Consistency enforcement in medical knowledge base construction.

Some aspects of knowledge base creation can be partially or completely automated, resulting in higher quality and smaller effort. Computer assistance is particularly valuable in ensuring the internal consistency of a knowledge base. The article describes several techniques for consistency enforcement in QMR-KAT, an interactive knowledge base editor for the INTERNIST-I/QMR medical knowledge base. Two strategies that improve consistency are applicable to a wide range of situations. The first strategy prevents simple (but common) inconsistencies. The second strategy reveals facts that are potentially (but not necessarily) inconsistent with known data, and may require further evaluation. Both strategies use the contents of the existing knowledge base in the evaluation of new facts.

Artificial Intelligence↗

Inferential knowledge acquisition.

This paper describes the approach we are pursuing for modeling inferential processes in knowledge-based systems. It is aimed at overcoming the lack of generality affecting many of the systems described in the literature. This mainly happens since the problem-solving method adopted by those systems is too closely tied to the particular domain problem over which the method itself has been modeled. We also describe a system called M-KAT (Medical Knowledge Acquisition Tool) which is useful in simplifying the process of acquiring inferential knowledge. M-KAT relies on an epistemological model of medical reasoning which represents a generalization of most of the problem-solving methods adopted in medical knowledge-based systems. The metarules formalism has been adopted as a mean for representing inferential knowledge and making its acquisition easier, thus allowing the computational implementation of the epistemological model of medical reasoning.

Artificial Intelligence↗

An object-oriented approach to knowledge representation in a biomedical domain.

An object-oriented approach has been applied to the different stages involved in developing a knowledge base about insulin metabolism. At an early stage the separation of terminological and assertional knowledge was made. The terminological component was developed by medical experts and represented in CORE. An object-oriented knowledge acquisition process was applied to the assertional knowledge. A frame description is proposed which includes features like states and events, inheritance and collaboration. States and events are formalized with qualitative calculus. The terminological knowledge was very useful in the development of the assertional component. It assisted in understanding the problem domain, and in the implementation stage, it assisted in building good inheritance hierarchies.

Algorithms↗

Knowledge and presence: accountability as described by nurses and surgical patients.

Accountability was an integral part of phenomenological descriptions of 24 patients' experience of having surgery and 24 nurses' understanding of their experiences. Patients and nurses discussed two major elements, knowledge and presence, although the emphasis on categories within these elements differed. Within the element of knowledge, nurses emphasized lacking knowledge, using professional knowledge, teaching, and leadership. Patients talked most about receiving teaching and individualized knowledge. Nurses also emphasized structure and process, and patients emphasized outcomes. Within the element of presence, nurses talked most about environmental barriers and interaction, and patients emphasized attentive attitude. This view of accountability may help restructure work environments to allow nurses to meet the needs that patients perceive themselves as having.

Adult↗

Enforcement of speed limits--actual policy and drivers' knowledge.

This paper reviews the penalty rules and examines drivers' perceptions of enforcement of speed limits. The survey was carried out using a sample of 204 Norwegian drivers, answering questions in a setting closely associated with their driving situation. For minor speeding offences drivers overestimated on average their fines. For serious speeding offences drivers significantly underestimated how many kilometers per hour they could exceed the speed limits before losing their driving license. They also overestimated the probability of being caught speeding. This resulted in a perceived expected penalty twice the real one. The paper also examines the relationship between different driver characteristics and their knowledge of the enforcement policy for speeding. Older drivers had less knowledge about the threshold level for serious speeding but more knowledge about the detection rate than younger drivers do. Experienced drivers had more knowledge about the threshold level for serious speeding than inexperienced drivers. The number of times drivers were stopped due to speeding offences increased their knowledge of fines for minor speeding.

Adult↗

Knowledge-discovery incorporated evolutionary search for microcalcification detection in breast cancer diagnosis.

OBJECTIVES: The presence of microcalcifications (MCs), clusters of tiny calcium deposits that appear as small bright spots in a mammogram, has been considered as a very important indicator for breast cancer diagnosis. Much research has been performed for developing computer-aided systems for the accurate identification of MCs, however, the computer-based automatic detection of MCs has been shown difficult because of the complicated nature of surrounding of breast tissue, the variation of MCs in shape, orientation, brightness and size. METHODS AND MATERIALS: This paper presents a new approach for the effective detection of MCs by incorporating a knowledge-discovery mechanism in the genetic algorithm (GA). In the proposed approach, called knowledge-discovery incorporated genetic algorithm (KD-GA), the genetic algorithm is used to search for the bright spots in mammogram and a knowledge-discovery mechanism is integrated to improve the performance of the GA. The function of the knowledge-discovery mechanism includes evaluating the possibility of a bright spot being a true MC, and adaptively adjusting the associated fitness values. The adjustment of fitness is to indirectly guide the GA to extract the true MCs and eliminate the false MCs (FMCs) accordingly. RESULTS AND CONCLUSIONS: The experimental results demonstrate that the incorporation of knowledge-discovery mechanism into the genetic algorithm is able to eliminate the FMCs and produce improved performance comparing with the conventional GA methods. Furthermore, the experimental results show that the proposed KD-GA method provides a promising and generic approach for the development of computer-aided diagnosis for breast cancer.

Algorithms↗

Memory systems for structural and semantic knowledge of faces and buildings.

It is an ongoing debate whether specific neurocognitive systems are involved in face and object recognition, particularly for analyses that require the access to stored structural and semantic knowledge. Here we compared the processing of familiar (at the exemplar level) and unfamiliar faces and buildings by recording event-related potentials in a repetition priming paradigm. We focused on the early repetition effect (ERE/N250r) which has been proposed to indicate the access to stored structural knowledge and the late repetition effect (LRE/N400), a possible indicator of semantic knowledge. An ERE/N250r was present for familiar buildings and smaller than for faces, but indistinguishable in terms of scalp topography. In contrast, the LRE/N400 was stimulus specific in topography. These findings suggest initial access to a common store of structural knowledge followed by the activation of category-specific cortical representations of person- and building-related semantic knowledge.

Adult↗

Knowledge acquisition and development of accurate rules for predicting protein stability changes.

Knowing the mechanisms by which protein stability change is one of the most important and valuable tasks in molecular biology. The conventional methods of predicting protein stability changes mainly focus on improving prediction accuracy. However, it is desirable to extract domain knowledge from large databases that is beneficial to accurate prediction of the protein stability change. This paper presents an interpretable prediction tree method (named iPTREE) that produces explanatory rules to explore hidden knowledge accompanied with high prediction accuracy and consequently analyzes the factors influencing the protein stability changes. To evaluate iPTREE and the knowledge upon protein stability changes, a thermodynamic dataset consisting of 1615 mutants led by single point mutation from ProTherm is adopted. Being as a predictor for protein stability changes, the rule-based approach can achieve a prediction accuracy of 87%, which is better than other methods based on artificial neural networks (ANN) and support vector machines (SVM). Besides, these methods lack the ability in biological knowledge discovery. The human-interpretable rules produced by iPTREE reveal that temperature is a factor of concern in predicting protein stability changes. For example, one of interpretable rules with high support is as follows: if the introduced residue type is Alanine and temperature is between 4 degrees C and 40 degrees C, then the stability change will be negative (destabilizing). The present study demonstrates that iPTREE can easily be used in the application of protein stability changes where one requires more understandable knowledge.

Algorithms↗

A randomized controlled trial of an educational intervention on Hellenic nursing staff's knowledge and attitudes on cancer pain management.

The purpose of this randomized controlled study was to explore the effectiveness of an educational intervention on nurses' attitudes and knowledge regarding pain management and to explore associations with nurses' characteristics. A four Solomon group experimental design was employed to assess the effect of the intervention and potential effects of pre-intervention testing. One hundred and twelve nurses were randomized to two intervention and two control groups. The intervention was based on viewing a series of educational videotapes and case scenarios. The Validated Hellenic version of the Nurses Knowledge and Attitudes Survey Regarding Pain (GV-NKASRP) was used. Pre-intervention scores revealed various limitations in regard to pain assessment and management. At the pre-test, the average number of correct answers was 17.58+/-7.58 (45.1%+/-19.3% of total questions). Pre-intervention scores differed significantly among participants with different educational backgrounds (P < 0.0001). A significant effect of pain education on total knowledge scores as well as regarding specific questions was detected. Intervention group participants provided 6.11+/-5.55 additional correct answers (15.66%+/-14.23% improvement, P < 0.0001), and they exhibited significantly improved post-test scores compared to controls (26.49+/-5.24 vs. 18.75+/-4.48; P < 0.0001). A potential negative effect of pre-test on knowledge gain for specific items and for total scores was detected. These findings suggest low pre-test knowledge scores among Hellenic oncology nurses and a significant effect of the intervention.

Adult↗

The emotions of integrating breastfeeding knowledge into practice for English midwives: a qualitative study.

BACKGROUND: Breastfeeding prevalence in the United Kingdom is one of the lowest in Europe. The midwife provides feeding support for new mothers but research suggests that midwives' knowledge of breastfeeding is limited. OBJECTIVE: To discover the views of English midwives in relation to their breastfeeding support role. DESIGN: Qualitative design. SETTINGS: Two maternity hospitals in Northwest England. PARTICIPANTS: Thirty midwives who cared for normal, healthy babies. Midwives were selected for interview using theoretical sampling principles from a pool of midwives who volunteered. Volunteers were accessed using a poster exhibited in relevant clinical areas. METHODS: Data were collected using audiotaped, in-depth interviews and were analysed using constant comparison techniques. RESULTS: The study highlights that differing professional knowledge and beliefs about breastfeeding support created intense, mainly negative, emotions for these midwives. Irritation and despair was experienced with the greater emphasis placed on research, rather than practice knowledge in policy and recommendations for practice. Disappointment was experienced when mothers did not conform to midwives' expectations. Conflict with differing peer-based knowledge generated feelings of intimidation and annoyance for some midwives. Some midwives demonstrated that they can sustain clinical decisions whilst based in a hostile environment, but others conformed to the practice expectations of their peers. Happiness was experienced when midwives described positive relationships with mothers, rather than their professional colleagues. CONCLUSIONS: The utilisation of professional knowledge in breastfeeding practice was a highly complex issue, and generated significant negative emotional distress, for these midwives.

Breast Feeding↗

Voice care knowledge among clinicians and people with healthy voices or dysphonia.

An important clinical component in the prevention and treatment of voice disorders is voice care and hygiene. Research in voice care knowledge has mainly focussed on specific groups of professional voice users with limited reporting on the tool and evidence base used. In this study, a questionnaire to measure voice care knowledge was developed based on "best evidence." The questionnaire was validated by measuring specialist voice clinicians' agreement. Preliminary data are then presented using the voice care knowledge questionnaire with 17 subjects with nonorganic dysphonia and 17 with healthy voices. There was high (89%) agreement among the clinicians. There was a highly significant difference between the dysphonic and the healthy group scores (P = 0.00005). Furthermore, the dysphonic subjects (63% agreement) presented with less voice care knowledge than the subjects with healthy voices (72% agreement). The questionnaire provides a useful and valid tool to investigate voice care knowledge. The findings have implications for clinical intervention, voice therapy, and health prevention.

Attitude to Health↗

Magnetic resonance angiography: from anatomical knowledge modeling to vessel segmentation.

Magnetic resonance angiography (MRA) has become a common way to study cerebral vascular structures. Indeed, it enables to obtain information on flowing blood in a totally non-invasive and non-irradiant fashion. MRA exams are generally performed for three main applications: detection of vascular pathologies, neurosurgery planning, and vascular landmark detection for brain functional analysis. This large field of applications justifies the necessity to provide efficient vessel segmentation tools. Several methods have been proposed during the last fifteen years. However, the obtained results are still not fully satisfying. A solution to improve brain vessel segmentation from MRA data could consist in integrating high-level a priori knowledge in the segmentation process. A preliminary attempt to integrate such knowledge is proposed here. It is composed of two methods devoted to phase contrast MRA (PC MRA) data. The first method is a cerebral vascular atlas creation process, composed of three steps: knowledge extraction, registration, and data fusion. Knowledge extraction is performed using a vessel size determination algorithm based on skeletonization, while a topology preserving non-rigid registration method is used to fuse the information into the atlas. The second method is a segmentation process involving adaptive sets of gray-level hit-or-miss operators. It uses anatomical knowledge modeled by the cerebral vascular atlas to adapt the parameters of these operators (number, size, and orientation) to the searched vascular structures. These two methods have been tested by creating an atlas from a 18 MRA database, and by using it to segment 30 MRA images, comparing the results to those obtained from a region-growing segmentation method.

Algorithms↗

Dissociating person-specific from general semantic knowledge: roles of the left and right temporal lobes.

The cognitive architecture and neural underpinnings of different semantic domains remains highly controversial. We report two patients with focal temporal lobe atrophy who presented with contrasting and theoretically informative dissociations of person-specific versus general semantic knowledge. Subject J.P. showed severely impaired person-specific semantics, with relative preservation of knowledge about objects and animals, while subject M.A. exhibited the opposite pattern of performance (good knowledge of people in the context of impoverished general semantics). Voxel-based morphometric analysis of MR images in the two cases established predominantly right temporal atrophy associated with J.P.'s deficit for person knowledge and predominantly left temporal atrophy in M.A. who was impaired in general conceptual knowledge.

Atrophy↗