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At least 127 records · Page 7Linked to original sources
PubMed2002

Reducing the risk of falls through proprioceptive dynamic posture training in osteoporotic women with kyphotic posturing: a randomized pilot study.

OBJECTIVE: To assess the effect of a proprioceptive dynamic posture training program on balance in osteoporotic women with kyphotic posture. DESIGN: Subjects were randomly assigned to either a proprioceptive dynamic posture training program or exercise only group. Anthropometric measurements, muscle strength, level of physical activity, computerized dynamic posturography, and spine radiography were performed at baseline and 1 mo. RESULTS: At the 1-mo follow-up, three groups were formed on the basis of the baseline computerized dynamic posturography results. In general, groups 1 and 2 had no significant change at 1 mo, whereas group 3 improved balance significantly at 1 mo. CONCLUSION: The subjects who had abnormal balance and used the proprioceptive dynamic posture training program had the most significant improvement in balance. Improved balance could reduce the risk of falls.

Accidental Falls↗
PubMed1998

Worry and risk perception.

Risk perception is sometimes measured by means of judgments about worry, sometimes as perceived risk more directly. However, perceived level of risk calls for a more intellectual judgment and worry tends to refer to emotional reactions. These two are therefore not the same and need not be strongly correlated. Results reported here show that perceived risk and worry are indeed weakly correlated, both for generalized worry and for more specific measures of worry matched with the same hazard as risk ratings. A distinction is suggested between cognitive, abstract hazards and concrete, sensory hazards, with implications for the worry-perceived risk relationship. It was furthermore found by means of cluster analysis that there were groups of subject displaying different dynamics of risk and worry.

Adolescent↗
PubMed1998

Risk assessment: a means for linking HACCP plans and public health.

HACCP plan adoption has greatly enhanced the food industry's ability to systematically design programs to ensure the microbiological safety of foods. Yet, this widening acceptance of the HACCP system has revealed several areas where its application is limited due to reliance on qualitative consideration of hazards and their control. In particular, HACCP planning is limited both conceptually and practically by its inability to quantify the potential combined influence of multiple control-point deviations and to relate the successful operation of a HACCP system to a measurable public-health impact. Recent advances in quantitative microbiological risk assessment appear to offer a means of overcoming these limitations. The integration of HACCP plans with the development of dynamic risk-assessment models offers a means for considering the entire farm-to-table continuum and for relating food-manufacturing operations to public health goals. Such capabilities may be critical to establishing equivalence among HACCP systems.

Food Handling↗
PubMedDate not supplied

Prognostic factors for the time of occurrence and dynamics of distant metastases and local recurrences after radical treatment in patients with rectal cancer.

BACKGROUND: A remarkable increase has been noted in the rate of incidence of rectal cancer. Post- or preoperative adjuvant treatment has significantly decreased the risk of local recurrence, but still only about 50% of all patients with rectal cancer treated radically can achieve a permanent cure. The majority of failures are due to distant metastases (DM) and/or local recurrences (LR). The risk and dynamics of failure after treatment of neoplasmtic disease has been analyzed on several occasions. MATERIAL AND METHODS: This retrospective study involved 161 consecutive patients with rectal cancer treated by radical surgery between 1972 and 1989. The mean age was 57 years. All patients underwent radical abdominoperineal rectum excision. The average follow-up was 10 years. In terms of the time elapsing to failure, the entire group of patients was divided into two subgroups: 'early' (occurring within 18 months after surgery) and 'late' (more than 18 months after surgery). RESULTS: The actuarial 5-year disease-free survival rate was 61.3%. Distant metastases occurred in 42 cases (26%), of whom 50% developed 'early' relapses, whereas local recurrences (29 cases - 18%) developed 'early' in 72% of the cases. Male gender was found to be an independent factor increasing the risk of 'early' relapses, particularly in the pN2 group. The stage of the disease is an indisputable risk factor for distant metastases and 'early' local recurrences. CONCLUSIONS: The time to failure varied significantly regarding local and distant relapses, suggesting different dynamics and origin. It seems that aggressive systemic and local treatment may decrease the incidence of relapses and improve long-term results. There is an urgent need to define new prognostic factors for identifying patients threatened by early dissemination.

Adenocarcinoma↗
PubMed2006

Characterizing the landscape dynamics of an invasive plant and risk of invasion using remote sensing.

Improved understanding of the spatial dynamics of invasive plant species may lead to more effective land management and reduced future invasion. Here, we identified the spatial extents of nonnative cheatgrass (Bromus tectorum) in the north central Great Basin using remotely sensed data from Landsat MSS, TM, and ETM+. We compared cheatgrass extents in 1973 and 2001 to six spatially explicit landscape variables: elevation, aspect, hydrographic channels, cultivation, roads, and power lines. In 2001, Cheatgrass was 10% more likely to be found in elevation ranges from 1400 to 1700 m (although the data suggest a preferential invasion into lower elevations by 2001), 6% more likely on west and northwest facing slopes, and 3% more likely within hydrographic channels. Over this time period, cheatgrass expansion was also closely linked to proximity to land use. In 2001, cheatgrass was 20% more likely to be found within 3 km of cultivation, 13% more likely to be found within 700 m of a road, and 15% more likely to be found within 1 km of a power line. Finally, in 2001 cheatgrass was 26% more likely to be present within 150 m of areas occupied by cheatgrass in 1973. Using these relationships, we created a risk map of future cheatgrass invasion that may aid land management. These results highlight the importance of including land use variables and the extents of current plant invasion in predictions of future risk.

Ecology↗
PubMed2003

Analysis of mortality decline along with age and latent congenital defects.

Mortality from congenital anomalies is inversely proportional to age after the age of 1 year. The theory of congenital individual risk explains this mortality decline. The overall aim of this study is to test whether the theory describes mortality decline for all diseases within the first year of life and after the age of 1. Mortality decline along with age was analyzed in five countries and for all causes of death. The theory of congenital individual risk describes well the real mortality decline for all diseases except malignant neoplasms after the birth. Decline of mortality is due to the dying out of the more impaired individuals. Mortality decline with the first power of age results from the selection before the birth. It is dominant and the frequency of defects decreases proportionally to the value of individual risk of death. In the case of identically probable defects, the selection does not occur and mortality declines with the square of age. Congenital defects were also identified as a cause of death in the case of infectious diseases occurring before the age of 10. Mortality from malignant neoplasms is age-independent within the age period 1-20 years and, contrary to all other diseases, no small subpopulation with a significant individual risk was identified.

Aging↗
PubMed2002

Extractable substances (anionic surfactants) from membrane filters induce morphological changes in the green alga Scenedesmus obliquus (Chlorophyceae).

The effect of filtration of medium through different kinds of filters (glass fiber, mixed esters of cellulose and nitrocellulose) on the morphology in the green alga Scenedesmus obliquus was examined. Several compounds potentially released from membrane filters were further investigated, and among them, two anionic surfactants were found to be morphologically active. Exposure to the anionic surfactants resulted within 2 d in the transformation of unicellular populations of Scenedesmus in populations dominated by colonies. Growth rates between control and surfactant-exposed populations were identical, and the morphological effect occurred at surfactant concentrations far below the reported no-observed-effect concentration for growth inhibition, stressing the need for inclusion of morphological appearance of Scenedesmus in algal toxicity testing to improve the assessment of ecological risks.

Animals↗
PubMed1990

The dynamics of HIV spread: a computer simulation model.

Mathematical modeling of the AIDS pandemic has been limited by the difficulty of satisfactorily representing the marked behavioral heterogeneity that characterizes the various populations at risk. We propose an approach which models the spread of infection as a discrete-event simulation using SIMSCRIPT, a powerful simulation language. The program developed provides sufficient flexibility to adequately represent and study a wide range of risk-group dynamics. Using this tool we have verified the May-Anderson prediction relating contact rate heterogeneity to the rate of HIV spread. We have also been able to assess the sensitivity of the model to the particular choice of distribution for contact rates, disease stage durations, and intercontact intervals. It is thought that this approach will permit the empirical testing of hypotheses which do not lend themselves to a purely mathematical treatment.

Acquired Immunodeficiency Syndrome↗
PubMed2006

Risks on the roads.

Explore the source record for details and available documents.

Accidents, Traffic↗
PubMed2005

Advances in the assessment and prediction of interpersonal violence.

This article underscores the weakness of clinical judgment as a mechanism for prediction with examples from other areas in the psychological literature. Clinical judgment has as its Achilles'heel the reliance on a person to incorporate multiple pieces of information while overcoming human judgment errors--a feat insurmountable thus far. The actuarial approach to risk assessment has overcome many of the weaknesses of clinical judgment and has been shown to be a much superior method. Nonetheless, the static/historical nature of the risk factors associated with most actuarial approaches is limiting. Advances in risk prediction will be found in part in the development of dynamic actuarial instruments that will measure both static/historical and changeable risk factors. The dynamic risk factors can be reevaluated on an ongoing basis, and it is proposed that the level of change in dynamic factors necessary to represent a significant change in overall risk will be an interactive function with static risk factors.

Antisocial Personality Disorder↗
PubMed2006

Static and dynamic patient characteristics as predictors of criminal recidivism: A prospective study in a Dutch forensic psychiatric sample.

If clinicians in forensic psychiatry want to reduce risk of reoffending in their patients, they require insight into dynamic risk factors, and evidence that these add predictive power to static risk indicators. Predictors need to be evaluated under clinically realistic circumstances. This study aimed to validate dynamic and static variables as predictors of reconviction in a naturalistic outcome study. Data on static and dynamic risk factors were collected for 151 patients discharged from Dutch forensic psychiatric hospitals. Community follow-up was prospective, with a 5.5 year minimum. A prediction model was developed using Cox regression analysis. The magnitude of the predictive power of this model was estimated using receiver operating characteristic (ROC) analysis. The final prediction model contained four static and no dynamic predictors. The model's ROC area under the curve was .79 (95% CI .69-.89). Clinical risk ratings were non-predictive. Post hoc analyses exploring the influence of subgroups of patients did not yield better models. It is concluded that a small set of static predictors yielded a good estimate of future reconvictions; inclusion of dynamic predictors did not add predictive power.

Crime↗
PubMed2007

Dynamic contrast-enhanced MRI as a predictor of tumour response to radiotherapy.

A predictive technique in the management of patients with cancer could improve the therapeutic index by allowing better individualisation of treatment. The standard risk factors that are currently used do not adequately account for the unpredictable and substantial variation seen in the treatment response of patients with a similar risk profile. Dynamic contrast-enhanced (DCE) MRI is a non-invasive technique that can provide anatomical and physiological information on the tumour. The DCE-MRI data reflects the tumour microenvironment variables that are known to influence radiation response. The aim of this review is to describe the potential clinical application of DCE-MRI as a predictor of radiation response. We have reviewed the literature and identified 29 studies (total of 1194 patients) that correlate DCE-MRI with histopathological or clinical outcome data relevant to radiotherapy.

Contrast Media↗
PubMed2004

Quantifying population recovery rates for ecological risk assessment.

Ecological effects of modern agrochemicals are typically limited to brief episodes of increased mortality or reduced growth that are qualitatively similar to natural disturbance regimes. The long-term ecological consequences of agrochemical exposures depend on the intensity and frequency of the exposures relative to the rates of recovery of the exposed populations. This paper explores the feasibility of using readily available life history information to quantify recovery rates of aquatic populations. A simple modeling framework based on the logistic population growth model is used to compare population recovery rates for different types of organisms and to evaluate the influence of life history, initial percent reduction, disturbance frequency, and immigration on the time required for populations to recover from simulated agrochemical exposures. Recovery models are developed for aquatic biota ranging in size and longevity from unicellular algae to fish and turtles. Population growth rates and recovery times derived from life history data are consistent with measured recovery times reported in mesocosm and enclosure experiments, thus supporting the use of the models for quantifying population recovery rates for ecological risk assessment.

Agrochemicals↗
PubMed1991

Sex, marital status, and suicide in Canada: 1951-1981.

Data from Canada for the period 1951-1981 are used to analyze the influence of marital status on suicide. "Using a standardization procedure, it was discovered that a transition from single or widowed to married would entail a greater reduction in suicide risk for men than for women. In the case of a transition from divorced to married status, both sexes would benefit equally in reducing suicide potential. The analysis further demonstrates only weak support for the thesis that over time there would be a convergence in sex differences in the potential protective significance of marriage in reducing suicide risk."

Americas↗