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At least 973 records · Page 54Linked to original sources

PubMed2001

Psychosocial factors, workload, and human error in a simulated pharmacy dispensing task.

Participants filled 42 orders on a task designed to simulate components of filling prescriptions. Task factors included objective workload of 70- versus 80-min. to complete the task and perceptions of workload dimensions using the NASA Task Load Index. The proportion and pattern of data-entry, counting, and product-selection errors were compatible with those found in pharmacy field-sites. Significant other relationship stress, field-dependence, and an 80-min. workpace predicted data-entry errors. Mistakes in product selection were associated with low GPA, high social stress, the NASA Task Load Index dimension of less concern with performing well, and a 70-min. workpace. Relationship of data to corresponding information in the pharmacy literature and to assumptions of a cognitive-systems performance model was discussed.

Adult↗

PubMed1994

Female nudity in advertisements, arousal and response: a parsimonious extension.

This study extended a 1990 report of LaTour, Pitts, and Snook-Luther by further analysis. Relationships between the key dimensions of High Activation (tension) and General Activation (energy) and ratings of attitude toward the advertisement were analyzed in a test of two hypothetical models performed on ratings by 134 undergraduate business students who responded to the paper-and-pencil tests which operationalized the constructs. In addition, attitude toward the brand was added to the formulation to evaluate the tenability of direct effects of arousal on attitude toward the brand (Ab) and indirect effects "filtered through" attitude toward the advertisement (Aad). Analysis supported the idea that excessive rated tension induced from an erotic advertisement has negative consequences. As predicted, different structural relations between these variables occur under different conditions.

Adult↗

PubMed1999

Dynamic responses of cattle to thermal heat loads.

The focal point of this limited review is bioenergetic research conducted in the Biological Engineering Research Unit at the U.S. Meat Animal Research Center (MARC), using recently developed instrumentation and analytical techniques. The dynamics of observed thermoregulatory responses in cattle to thermal heat load challenges are explored, with an emphasis on physiological and behavioral parameters of body temperature, respiration rate, and feed intake. Observations of body temperature, especially tympanic temperature, have shown hot environments to cause phase shifts, increased amplitude, and increased means for diurnal rhythms. Fractal analysis of body temperature records obtained at 2- to 10-min intervals has been found to be robust for objectively differentiating among responses of cattle in cool to hot environments, and it indicates a stress threshold of approximately 25 degrees C (coincident with declining feed intake). Other analyses determined a 21 degrees C threshold for increased respiration rate. The reported observations and analyses provide further understanding of how and why the animals respond to environmental challenges, an understanding that is necessary for refining performance models and developing energetic and thermoregulatory models. The dynamic responses are discussed in the context of establishing criteria for proactive environmental management for cattle during hot weather, using heat waves as an example.

Animals↗

PubMed1995

Traumatic brain injury: factors predicting return to work or school.

Prediction of outcome for brain-injured individuals will facilitate effective rehabilitation programme planning which will ultimately improve the patient's quality of life. A sample of traumatic brain-injured subjects who had completed their rehabilitation were contacted post-discharge to identify predictive factors for return to work/school. Subjects were given a telephone interview and their charts were examined retrospectively along five subsets of variables in the predictive matrix: sociodemographics, chronicity, indices of severity, physical impairment, and cognitive functioning. Forty-five subjects were used as the study sample to investigate their vocational and educational outcome, and to generate the best predictive model for return to work/school. Twenty subjects made up the test sample used to evaluate the generalizability of the predictive model. Performance IQ score of the Wechsler Adult Intelligence Scale-Revised emerged as the most significant predictor of return to work/school. Implications of these findings for treatment and rehabilitation are discussed.

Activities of Daily Living↗

PubMed1999

The importance of shunt valve position in flow characteristics of the Medtronic PS Medical Delta valve.

This study was conducted to document the extent to which flow depends on valve position in relation to head-pressure reference. Medtronic PS Medical Delta valves (contour model, performance levels 0.5, 1.0, 1.5, and 2.0) were studied in a bench test designed to evaluate flow rates with respect to valve position in relation to the head-pressure reference postion. The valves were connected to an "infinite" reservoir by the standard inlet catheter. An initial head (proximal) pressure was selected for each valve based on package insert data. The position of the inlet catheter tip was fixed at this starting head pressure, thus making the inlet catheter tip position the reference for relative head pressures on the valve assembly. When the valve body is positioned above this level, the effective head pressure is lowered, and when the valve body is positioned below this level, the effective head pressure is raised. Flow was established with the siphon control portion of the valve body located on the same horizontal level as the inlet catheter tip (the reference head pressure or "0" position). A standard silastic catheter was attached to the outlet of the valve, and its length was fixed at 50 cm for all valves (-50 cm H(2)0). The distal end of the outlet catheter was connected to a fraction collector, and 1-minute samples (five replicates) were collected for gravimetric determination of flow rate. The valve assembly was then moved in 1-cm increments through the range of 4 cm above to 8 cm below the head-pressure reference position. Samples were collected from each position (4 cm to -8 cm) relative to the inlet catheter tip. Flow rate, in milliliters/hour, was plotted against both relative position (4 cm to -8 cm) and absolute head pressure (in centimeters of water). Each of the valves tested was shown to have a linear relationship between flow and position relative to the inlet catheter tip (or absolute head pressure). The average increase in flow per centimeter of displacement of valve from catheter tip was 16.5 ml/hr/cm (range 14.4-17.6 ml/hr/cm). Once the inlet catheter tip is fixed in position, it serves as a pressure reference. Movement of the valve above this level results in a net decrease in effective head pressure, and movement below this position results in a net increase in effective head pressure. Thus, the positioning of shunt valves in locations different from this pressure reference position should be performed only with the knowledge that significant increases in outflow rate may occur when the valve body is positioned lower than the inlet catheter tip. This increase in outflow rate is not the result of siphoning or a defect in the antisiphon device but instead the result of a net increase in effective head pressure.

Journal Article↗

PubMed2005

NAV: a tool for producing presentation quality animations of graphical cognitive model dynamics.

Computational models of cognition often exhibit complex dynamics that are difficult to discern without the use of visualization tools. Current tools often provide insight only to the modeling expert, however, and they provide limited functionality for communicating model dynamics to the nonexpert, as is needed during scientific presentations and in educational settings. We present NAV, the Node Activity Visualizer, an easy-to-use and portable software tool that interactively transforms the output of cognitive modeling simulators into presentation quality animations of model performance.

Cognition↗

PubMed2004

DNA fusion vaccines induce targeted epitope-specific CTLs against minor histocompatibility antigens from a normal or tolerized repertoire.

We have designed DNA fusion vaccines able to induce high levels of epitope-specific CD8(+) T cells, using linked CD4(+) T cell help. Such vaccines can activate effective immunity against tumor Ags. To model performance against minor histocompatibility (H) Ags important in allogeneic hemopoietic stem cell transplantation, responses against the H2D(b)-restricted Uty and Smcy male HY epitopes have been investigated. Vaccination of females induced high levels of tetramer-specific, IFN-gamma-producing CD8(+) T cells against each epitope. Vaccines incorporating a single epitope primed effector CTL able to kill male splenocytes in vitro and in vivo, and HY(Db)Uty-specific vaccination accelerated rejection of syngeneic male skin grafts. Priming against either epitope established long-term memory, expandable by injection of male cells. Expanded CD8(+) T cells remained specific for the priming HY epitope, with responses to the second suppressed. To investigate vaccine performance in a tolerized repertoire, male mice were vaccinated with the fusion constructs. Strikingly, this also generated epitope-specific IFN-gamma-producing CD8(+) T cells with cytotoxic function. However, numbers and avidity were lower than in vaccinated females, and vaccinated males failed to reject CFSE-labeled male splenocytes in vivo. Nevertheless, these findings indicate that DNA fusion vaccines can mobilize CD8(+) T cells against endogenous minor H Ags, even from a profoundly tolerized repertoire. In the transplantation setting, vaccination of donors could prime and expand specific T cells for in vivo transfer. For patients, vaccination could activate a potentially less tolerized repertoire against similar Ags that may be overexpressed by tumor cells, for focused immune attack.

Animals↗

PubMed1994

Person-environment assessments in occupational therapy.

Occupational therapists have begun to recognize the importance of considering how the environment influences occupational performance. Models of person-environment fit provide a theoretical context within which occupational therapists can consider the influence of the environment on function. The challenge for occupational therapists is to select assessments that incorporate concepts of person-environment fit. However, limited awareness of appropriate environmental assessments that have undergone psychometric testing has limited their introduction into clinical practice. This paper reviews 41 environmental assessments and considers each in terms of its purpose, environmental attribute, environmental application, clinical utility, instrument development, and psychometric testing. A case example illustrates the applicability to the practice of occupational therapy.

Activities of Daily Living↗

PubMed2000

Tarsal functions, movement, and stabilization mechanisms in foot, ankle, and leg performance.

The authors investigated the function of the tarsus and the skeletal segments of the foot in terms of the biomechanical significance of the individual links of the foot-ankle-leg complex. A performance model based on pressure-washed trabecular systems and the interface of the different segments making up the articular foot skeleton is presented and discussed. The biomechanical influence of these segments on each other and on their appendicular companion bones is assessed, and an explanation of their function is provided.

Ankle↗

PubMed1999

An investigation of social and class differences in very-low birth weight outcomes: a continuing public health concern.

The objective of this study was to examine the relationship of nonmedical factors, including socioeconomic status, social class, education, race, and social support, to low birth weight. In a case-control study of all resident very-low-birth-weight births between December 1, 1989, and March 31, 1991, mothers completed an extensive survey related to their experience of pregnancy, including prenatal and postnatal care. Cases were defined as very-low-birth-weight (VLBW) infants and were matched to moderately-low-birth-weight and normal-birth-weight infants in race, age, and maternal residence. The hypothesis that social and class factors are more predictive of low birth weight than medical factors alone for women without chronic health problems was supported. Although the degree of the association varies depending on birth weight outcome, race even though addressed through matching--continued to play an important role in birth outcomes. A comparison of logistic model performance with and without the inclusion of social factors indicated the importance these variables play in prediction of birth outcomes. This is one of the few studies undertaken that explicitly investigates impact of patient factors on medical care.

Adult↗

PubMed2000

Randomized community trial of a breast self-examination skills-building intervention for inner-city African-American women.

OBJECTIVE: Breast cancer is the most common cancer in women, and African-American women are less likely to detect breast cancer at its early stages. Few controlled trials of interventions to increase breast self-examination (BSE) among low-income minority women have been conducted. Our objective was to test a small-group workshop intended to build BSE skills and promote BSE among low-income African-American women. METHODS: A randomized community field trial tested a BSE skills-building workshop based on social cognitive theory of behavior change compared to a matched sexually transmitted diseases prevention workshop, with one- and three-month follow-ups for assessing increased practice of BSE. RESULTS: Women who did not regularly practice BSE and participated in a BSE skills-building workshop were more likely to practice BSE than women in the comparison intervention at the one- (OR = 3.5, p = 0.04) and three-month follow-ups (OR = 4.9, p = 0.01). These results were not related to risk perceptions heightened by the intervention. Across conditions and controlling for covariates in a multivariate model, performing regular BSE was most closely associated with having received any formal BSE instruction. CONCLUSION: BSE skills building can effectively increase use of BSE among low-income African-American women who face multiple and competing health risks. The small-group experience is an important element in fostering norms for practicing BSE and enhancing BSE practices.

Adolescent↗

PubMedDate not supplied

[Neuropsychological sequelae of head injury].

INTRODUCTION AND DEVELOPMENT: Traumatic brain injury (TBI) neuropsychological sequelae are consequence of the combination of focal and diffuse cerebral lesions. Foci of concussion usually involves frontal lobes. Fronto-basal lesions produces important changes in mood, personality and behavior, and dorsolateral lesions impairment of executive functions (lack of planning, flexibility and use of strategies). Left temporal concussion can produce aphasia. Hippocampal and parahippocampal atrophy are essentially responsible of memory dysfunctions. Diffuse axonal damage is related to impairment of attention, speed of mental processing and frontal lobe functions. The development of neuroimaging techniques, especially tridimensional magnetic resonance acquisition and analysis, allows accurate anatomo-functional correlates. Genetic variables can explain in part individual differences in the degree of memory impairment and the relationship of TBI with Alzheimer's disease. CONCLUSIONS: The TBI percussion model performed in rat and mouse allows the study of the interrelationship among structural damage, memory changes, genetic factors, and the effects of pharmacological treatment.

Brain↗

PubMed1975

Component resolution indices for scintillation camera systems.

From published overall resolution indices for three Anger camera systems, measured with three straight-bore collimators and 99mTc in air and with a water absorber present, the components due to inherent camera resolution, collimator geometry, and scatter are derived at various depths. Replacement of S-11 multiplier phototubes by bialkali phototubes improves calculated inherent Pho/Gamma III camera resolution by about 30% and by a further 33% upgrading to a high-performance model. At distances 2, 5, 8, and 10 cm from each collimator face with an intervening water absorber, mean scatter components of overall resolution indices are 6, 8, 9, and 10 mm, respectively. In typical clinical 99mm Tc imaging situations with a scattering medium present, the relative contributions of camera, collimator, and scatter to the total overall system resolution are presented.

Radionuclide Imaging↗

PubMed2002

Improving structure-linked access to publicly available chemical toxicity information.

Publicly available toxicity databases serve as the central resource in efforts to develop algorithms for assessing potential chemical toxicity. File standardization and linkage of chemical structures with chemical toxicity information are essential first steps in providing broad access to existing toxicity information, for deriving useful structure-activity relationship (SAR) models, performing analog searches, and estimating the potential toxicity of new chemicals. This review will focus on current efforts to improve structure-linked access to publicly available sources of toxicity information, outlining current web-based resources as well as two new database initiatives for standardizing and consolidating public chemical toxicity information.

Computer Communication Networks↗

PubMed2002

[Creation of emergency care services in developing countries: luxury or necessity?].

Organization of emergency care services prior to hospital admission has progressed at a satisfactory pace in developed countries. A performance model in this field is the French emergency service called service d'aide médicale d'urgence (SAMU). Socioeconomic conditions prevailing in developing countries have pushed authorities to give priority to preventive medicine. However numerous patients especially young people and women during childbirth die as a result of inadequate facilities for transportation from hospitals and dwellings in outlying areas to major medical centers where the best medical equipment and staff are available. As a result, it may be asked if emergency care services is really a luxury. The authors base their conclusion on analysis of the conditions and outcome of emergency patient care in three African countries in which it is essentially a requirement.

Adult↗

PubMed2003

[New models in the model (Managerial challenges in the Hungarian managed care model)].

The Hungarian managed care model integrates the different levels of health care services. Its goal is a more efficient resource allocation within the health care system, quality improvement of services, developing incentives and financing methods. The basic concept of the model is to introduce the benefits of the American managed care and the British fundholding system. The managed care model brought a new approach in the Hungarian health care system and meets a lot of expectation in both professional and political context. The model has certain problems, but these are handled at macro level. Without an integrated approach of macro, meso and micro levels is hardly believable the efficient and effective functioning of the model. Such macro level problems are the cost-efficiency versus high quality health services, financing incentives, and risk taking. At meso and micro level we are facing with questionable efficiency and effectiveness of the MCOs other health care organisations, which are based on strong bureaucratic paradigms and are convicted to a long lasting crisis in their changing environment. The integrated use of Mintzberg's management models (machine model, network model, performance-control model, virtual government model and normative-control model) adapted by us for the Hungarian managed care model could resolve certain problems or make them at least more solvable. In the changing environment of the health cares organisations the top management has to frame the change-scenario, to initiate, realise and sustain organisational changes. Achieving this, the proposed management models are a useful support. Their practical application could contribute to the efficient and effective functioning of the Hungarian managed care model at macro, meso and micro levels, as well.

Health Care Reform↗

PubMed2004

What insurers know about your hospital ... and how they are using it.

Insurers are using their purchasing power and their enormous stores of claims data to push hospitals to improve quality. Health plans are able to parse the data according to such quality indicators as cost, length of stay and outcomes. Hospitals are wary of the trend, but some welcome it, especially if insurers use the so-called pay-for-performance model.

Benchmarking↗

PubMed1992

Comparison of different information content models by using two strategies: development of the best information algorithm for Iliad.

Iliad is a diagnostic expert system for internal medicine. Iliad's "best information" mode is used to determine the most cost-effective findings to pursue next at any stage of a work-up. The "best information" algorithm combines an information content calculation together with a cost factor. The calculations then provide a rank-ordering of the alternative patient findings according to cost-effectiveness. The authors evaluated five information content models under two different strategies. The first, the single-frame strategy, considers findings only within the context of each individual disease frame. The second, the across-frame strategy, considers the information that a single finding could provide across several diseases. The study found that (1) a version of Shannon's information model performed the best under both strategies---this finding confirms the result of a previous independent study, (2) the across-frame strategy was preferred over the single-frame strategy.

Algorithms↗