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Recent advances in genetics directly affect family physicians. Many diagnostic tests are currently available to screen the fetus for malformations and genetic diseases, and gene therapy is slowly becoming a reality. This article discusses some of the screening techniques available, including chromosome analysis, ultrasound, and DNA studies.
Neuropsychological deficits following closed head injury are responsible for a significant part of the post-traumatic syndrome. Nonetheless such deficits frequently elude standard neurological examination and head injured subjects are not recognised as suffering from any impairments, despite these having a significant effect on their ability to return to work. As a result, subjects are refused disability status, resulting in a large number of litigation appeals. The criteria for determining disability status after head injury are often inadequate, as they do not take into account the post-traumatic syndrome, and medical experts, if they are sensitive to these issues are left in a quandary as to how to justify their decisions before the courts. Equally, psychological assessment, where it is included, is frequently limited to the examination of intellectual functions and memory, which are not always grossly disturbed in these cases. It is recommended that neuropsychological assessments should form part of routine practice in the evaluation of outcome in closed head injury and the test instruments be of adequate sensitivity to measure the deficits occurring after head injury. However, it is necessary to bear in mind that these subjective symptoms, which in reality hamper subjects' ability to return to work, may be the result of disruption of fine cognitive functions, which are inaccessible to currently available test methods.
Health professionals are investigating an increasing number of possible disease clusters, and statistical tests play an important role in cluster description and analysis. Existing cluster statistics assume precise data, when in reality health events are often imprecise (for example, place of residence is known only to the census district or zip code) and uncertain (for example, 'I first became ill sometime in 1985'). This incompatibility--precise methods used to analyse imprecise data--is largely ignored, resulting in test statistics of unknown accuracy. Most cluster statistics can be written as the cross-product of two matrices where one matrix reflects nearest-neighbour, distance or adjacency relationships and the second matrix is health related (for example, case-control identities). This paper explores a general approach to clustering, which incorporates uncertainty regarding space-time locations into these nearest neighbour, distance or adjacency relationships. Because the approach is general it can be used with almost all existing cluster tests, and, because it accounts for imprecise location data, it is suited to the 'real-world' nature of disease cluster investigations.
Virtual reality was used to sequentially present objects within a town square and to test recognition of object locations from the same viewpoint as presentation, or from a shifted viewpoint. A developmental amnesic case with focal bilateral hippocampal pathology showed a massive additional impairment when tested from the shifted viewpoint compared with a mild, list length-dependent, impairment when tested from the same viewpoint. While the same-view condition could be solved by visual pattern matching, the shifted-view condition requires a viewpoint independent representation or an equivalent mechanism for translating or rotating viewpoints in memory. The latter mechanism was indicated by control subjects' response latencies in the shifted-view condition, although the amnesic case is not impaired in tests of mental rotation of single objects. These results show that the human hippocampus supports viewpoint independence in spatial memory, and suggest that it does so by providing a mechanism for viewpoint manipulation in memory. In addition, they suggest an extremely sensitive test for human hippocampal damage, and hint at the nature of the hippocampal role in episodic recollection.
Several current hypotheses consider the process of attribution of importance to stimuli and the integration of actually perceived reality with experience as a cognitive base for the genesis of delusions. We tested these models by a comparison of deluded schizophrenics, healthy controls, and anxious patients on reasoning under uncertainty. Reasoning under uncertainty was examined in currently deluded schizophrenics (n = 29), in 16 of them also in remission, in normal control groups (n = 35), and in anxious patients (n = 31) using a probabilistic inference task. Acutely psychotic schizophrenics were less ready than normal subjects, anxious patients, and schizophrenics, in remission to modify their judgement in probabilistic situation confronted with potentially disconfirmatory data. They were also less prone than anxious patients and schizophrenics in remission to correct their estimate confronted with confirmatory data. The data support the hypothesis of a weaker influence of incoming stimuli on reasoning under uncertainty as a cognitive base of the maintenance of delusions.
Practice inevitably narrows over time. Therefore, testing of established doctors requires that their assessment be tailored to a far narrower practice than is appropriate for testing of new doctors who have not yet differentiated. In this paper, we address the conceptual challenges of tailoring physician assessment to individual practice. Testing of established doctors needs to reflect that physicians specialise, often in idiosyncratic ways; otherwise, the testing will not be credible among established doctors and will not reflect the realities of their practice. Despite the importance of these goals, the conceptual and methodological challenges of creating tailored assessments remain daunting.
Drug craving has purportedly been linked to relapse and to substance use. For over two decades, cue reactivity has been a viable method to assess craving and physiological reactions to drug stimuli. However, traditional cue reactivity has faced the following limitations: austere situations or stimuli, lack of complex cues, lack of standardization, and limited generalization outside of the lab setting. In order to improve cue methodologies, a virtual reality (VR) nicotine cue reactivity assessment system (VR-NCRAS) was developed and tested in a controlled experimental trial. Ten nicotine dependent smokers were exposed to VR smoking cues and VR neutral cues in a standardized, timed, computer controlled experiment. Subjective craving and physiological responses were recorded and compared across VR-NCRAS stimuli. Subjective cigarette craving increased significantly and corresponding physiological reactivity was observed in response to VR smoking cues. VR neutral cues did not result in subjective or physiological changes consistent with craving. Implications of these findings on substance abuse research and treatment are discussed.
This study seeks to gain an understanding of the learning experiences of district nurse students in the learning environment of the community, and to examine learning in the practice setting from the perspective of the student. Since the research depends upon the changing and differing interpretations of the individuals involved in the natural setting of the community, an ethnographic approach has been adopted. The experiences of students are monitored throughout the taught practice element of the district nurse course in both inner city and rural/urban locations. Data, collected through interview and observations, are analysed in the context of theory relating to adult learning and learning from experience. Three major categories are identified. Examples from these categories are identified and discussed. The categories are sequential and represent the learning process experienced by the students in the practice setting as they learn to fit into a new environment, test out their own ideas and compare the unreality of college with the reality of practice. Attention is drawn to the difficulties for students of fitting into new settings and trying out change, to the detrimental effect on learning of rigid practice routines and to the powerlessness of community practice teachers to exert a major influence on the learning environment. These issues are discussed in the context of changes in nurse education and evaluation of the community learning environment.
OBJECTIVE: To understand the processes that constrain the capacity of statutory organisations to work effectively with lay communities and to develop a model to enhance their capacity to do so. METHODS: The research consisted of three elements: a review of relevant literature; in-depth interviews with a purposive sample of people who had recently been involved in community-statutory sector partnership; and a deliberative workshop involving ten expert witnesses, selected to reflect a range of sectors and levels within organisations. RESULTS: Many factors contribute to a lack of effective strategic partnerships between lay communities and statutory organisations. These factors fall into five domains: the community's capacity to engage; the skills and competencies of organisational staff; the dominant professional service culture; the overall organisational ethos and culture; and the dynamics of the local and national political systems. A model of the relationships and/or interaction between these domains is postulated. There is potential for testing this model with statutory organisations to see whether it concurs with their reality and whether it is enhancing their organisational capacity. CONCLUSIONS: Commonly occurring constraints to effective partnerships between statutory organisations and lay communities need to be identified and addressed by applying a dynamic model of the type presented here.
The CAREN project concerns the development of a virtual reality environment in which the agility of healthy subjects and patients can be tested in a variety of reproducible conditions. CAREN is made by customizing hardware and developing software to enable measurements of motion of a subject in detail as a response to a perturbation from the computer driven motion platform. After feeding the data in a human body model simulation, joint moments of force and muscle activation can be calculated. From the time patterns of these responses, inferences can be made concerning the motor programs the subjects launch. Any primary problem in a motor program, resulting in functional failure or inadequacy, can be identified down to the joint and muscle group. Secondary adaptations of patients to a limitation in the periphery (such as lack of muscle force) can be separated from the primary ones. Inadequacy of complete motor programs in children with movement disorders can be classified, recorded and related to progress that may occur. Especially the understanding of compensation strategies in patients may lead to a better therapeutic attitude. CAREN offers not only a test environment with means of almost unlimited exploratory behaviors for patients, but constitutes also a strong tool for motor control research.
According to experiential structuralism, thought abilities have six capacity spheres: experimental, propositional, quantitative, imaginal, qualitative, and metacognitive. The first five are applied to the environment. The metacognitive capacity is applied to the others, serving as the interface between reality and the cognitive system or between any of the other capacities. To test this postulate, 648 subjects aged 12 to 40 years, solved eight tasks that were addressed, in pairs, to the first four capacity spheres. One of the tasks in each pair tapped the first and the other the third formal level of the sphere. Having solved the tasks, the subjects were required to rate each pair of tasks in terms of similarity of operations, difficulty, and success of solution. Factor analysis of difficulty and success evaluation scores revealed the same capacity-specific factors as the analysis of performance scores. Factor analysis of similarity scores differentiated between same- and different-sphere pairs. Analysis of variance showed that difficulty and success evaluation scores preserved performance differences between the first and the third formal tasks. Cognitive level, age, socioeconomic status, and sex were related to the metacognitive measures in ways similar to their relations to performance measures. These findings were integrated into a model aimed at capturing real-time metacognitive functioning.
The probability method of analysis of astigmatism variations respects both astigmatism components, quantity and axis. The two random variable model that we introduce here analyses cylinder variations and axial variations. After describing the contingency table and the probability table. Expectation of each component and its confidence interval are calculated together with the variance and the standard deviation. Covariance and correlation are calculated. If we want to compare different groups we test cylinders with cylinders and axes with axes. This method does not distort reality and is applicable to the semi meridians from 0 degree to 360 degrees. Only large samples of patients can be studied by this method.
Malaria, especially that caused by Plasmodium falciparum, is the most important parasitic disease of man. The complexity of the life cycle, the transmission dynamics in different endemic settings, and the spread of resistance to various drugs by the parasite and to insecticides by the vector render control strategies very difficult. An effective vaccine against malaria would represent a major strengthening of control. Research efforts to identify and select antigens for vaccine development have been substantial, particularly in the past 20 years. Various molecules from the pre-erythrocytic, asexual blood and sexual stages have been described and tested in experimental systems, and some may become interesting vaccine candidates. A crucial step was taken with the development of SPf66, a synthetic polypeptide based on pre-erythrocytic and asexual blood-stage proteins of Plasmodium falciparum. The concept of the SPf66 vaccine is not the prevention of clinical malaria but reduction of morbidity, and it is thus suitable for endemic areas, particularly Africa. The clinical phase III trials so far undertaken in Latin America and in Africa have clearly documented the safety, immunogenicity and partial efficacy of SPf66 against clinical malaria. The efficacy estimates of all trials are below those we generally demand from vaccines and when we aim to induce sterile immunity. Therefore, a large number of issues at the field and laboratory levels, such as ways of optimizing efficacy (doses, timing, age of vaccination), and understanding the mechanisms of action and effectiveness, need to be investigated before one can consider the public health use of SPf66 as a component of an integrated malaria control programme. The substantial tasks ahead involve (1) improving the vaccine which we have and (2) devising and testing new vaccines which may prove more efficacious. Malaria vaccines are now a reality, and the achievements of SPf66 to date, the ongoing research efforts with other vaccine candidates, and the potential of DNA vaccines make it possible to predict that widespread use of an efficacious vaccine no longer represents an unrealistic target.
To improve training facilities for surgeons, a surgical training system based on virtual reality techniques has been developed. The goal of the developed system is to improve education of surgeons by making the knowledge of expert surgeons directly available to trainees. The system realizes two different approaches: the library and the driving school paradigm. In its current form, the system consists of two modules. The main module combines the virtual reality kernel KISMET, a visual and haptic display, and a database of different operations and/or techniques. The master station is a copy of the input and output facilities of the main module. Both modules communicate by a TCP/ IP-based connection. Initial tests demonstrated the feasibility of the chosen framework. Further developments include the gathering of data not only from virtual reality but also from real operations. Robotic-assisted surgery provides an attractive way of accomplishing this.
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PURPOSE: The present study aims to verify the effectiveness of the reality therapy for patients with schizophrenia. METHODS: It is designed as a quasi-experimental study by which a nonequivalent control group pretest-posttest is conducted. The test was conducted with 30 patients with schizophrenia who were hospitalized at a mental hospital in South Korea. Fifteen of the patients participated in the reality therapy program while another 15 in the control group. The effects are measured by marking scores in the areas of the locus of control, self-esteem, and problem-focused stress coping of each participant. RESULTS: The general characteristics and dependent variables related to outcome variables were controlled to be equal between the two groups. It turns out that the internal locus of control, self-esteem, and problem-focused stress coping are statistically significant. CONCLUSION: Findings show that the reality therapy caused positive changes in terms of the internal locus of control, self-esteem, and problem-focused stress coping of the observed schizophrenic patients.
Virtual reality (VR) entails the use of advanced technologies, including computers and various multimedia peripherals, to produce a simulated (that is, virtual) environment that users perceive as comparable to real world objects and events. In recent years, virtual reality technologies have begun to be used as an assessment and treatment tool in occupational therapy, in part because of the ability to create environments that provide patients with opportunities to engage in meaningful, purposeful tasks that are related to real-life interests and activities. The objective of this study was to determine the suitability and feasibility of using a PC-based, non-immersive, VR system (that is, a system in which the user has a reduced sense of actual presence in and control over the simulated environment) for training individuals with unilateral spatial neglect to cross streets in a safe and vigilant manner. A virtual environment, consisting of a typical city street, was programmed using Superscape's 3D-Webmaster, a 3D web-authoring tool. Twelve subjects, aged 55 to 75 years, participated in the initial feasibility study and, to date, a further eight subjects have participated in the intervention study. Six of the initial subjects and all eight of the intervention subjects had sustained a right hemispheric stroke at least 6 weeks prior to the study. The remaining subjects were healthy age-matched adults who were independently mobile and had no difficulty in crossing streets. The results show that this virtual environment was suitable in both its cognitive and motor demands for the targeted population and indicate that the virtual reality training is likely to prove beneficial to people who have difficulty with crossing streets. The generalizability of these results, and recommendations regarding the use of virtual reality as an occupational therapy intervention, must be substantiated by further studies using a range of VR platforms with people with different cognitive and motor disabilities.