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PubMed1994

Factors associated with dangerous behavior in forensic inpatients: results from a pilot study.

This study was designed to identify risk factors associated with violence within a forensic inpatient hospital setting. The primary purpose was to develop a screening tool to aid in the rapid identification of patients requiring high versus low security ward placement. Subjects included 232 consecutive admissions during a five-month period to a 300-bed forensic division within a public-sector psychiatric hospital. Demographic, historical, and current clinical variables were collected, and dangerous behaviors were documented by nursing staff on a daily basis. The associations between dangerous outcomes and various risk factors were examined using chi-square or t tests, as appropriate. Stepwise logistic regression analysis was performed to assess the contribution of each risk factor significantly associated with violent behavior. A strong association was found between 10 risk factors and the incidence of violence in our forensic population. These factors included current clinical factors (grossly inappropriate behavior observed on the ward, an assessment of current escape risk); historical factors (psychiatric hospitalization history, criminal history variables, and a self-report of prior violence); and one demographic variable (length of stay). Of the 10 risk factors then included in the stepwise regression analysis, four contributed significantly to the final predictive model. Grossly inappropriate behavior, patient self-report of prior violence, history of psychiatric hospitalization, and a history of 10 or more prior psychiatric hospitalizations were most predictive of a violent outcome. Although situational and environmental variables also must be incorporated into final assessments and decisions, the identified significant variables can provide an additional tool in the rapid assessment of violence potential.

Dangerous Behavior↗
PubMed2000

Sensitivity analysis of mercury human exposure.

We present a comprehensive analysis of the sensitivity of mercury (Hg) human exposure to environmental variables using a multimedia model of the fate and transport of Hg in the environment. The results of the analysis show that the Hg dose is most sensitive to the lake pH, the burial rate of Hg adsorbed to sediments, and the chemical speciation of Hg emissions to the atmosphere. The lake pH has a strong non-linear effect on the methylation rate and bioaccumulation of Hg in fish. The burial of sediments is a major pathway for removing Hg from the lake cycling. The speciation of Hg emissions is important because Hg(II) is deposited much more rapidly than Hg(0). These results highlight the importance of key variables that should be investigated through well-designed field programs, so that we can minimize the overall uncertainties associated with the modeling of mercury fate and transport.

Confounding Factors, Epidemiologic↗
PubMed2001

Living with support in the community: predictors of choice and self-determination.

Ensuring that people with intellectual disability experience typical levels of choice and self-determination has become an essential objective for quality disability services. Three perspectives on self-determination were identified in the literature: psycho-educational, ecological, and socio-political. Personal characteristics, specific self-determination competencies, and environmental variables all were found to be associated with choice and self-determination. Living environments that were smaller and more individualized were linked to greater choice and self-determination. The theoretical perspective investigators applied to the issues influenced approaches to research and intervention, and differences in emphasis were evident regarding the relative importance of self-determination competencies and environmental factors. MRDD Research Reviews 7:91-98, 2001.

Choice Behavior↗
PubMed1996

Effects of preweaning environmental stimulation on neuronal and behavioral impairment produced by undernutrition.

The present study investigates the effects of sensorimotor stimulation on the basal dendrogenesis of superficial cerebrocortical neurons and the accomplishment in the associated exploratory behavior in rats simultaneously exposed to nutritional deprivation. Sprague-Dawley albino rats were submitted to nutritional-environmental influences from birth to the 21st postnatal day. Exploratory behavior was assessed by the evaluation of locomotor activity in the open-field apparatus. In order to evaluate changes in neuronal morphology induced by nutritional-environmental variables, brains were stained according to the Golgi-Cox-Sholl procedure. Dendritic development was assessed under camera lucida by measuring basal dendritic branching of layer II and III pyramidal neurons, located in the dorsomedial region of the visual cortex of the rat. Morphometrical analysis revealed that both basal dendritic length and branching were significantly reduced by undernutrition. In contrast, environmental stimulation during the suckling period compensated for the neuronal impairment produced by protein-calorie deprivation. An improvement was also observed in exploratory behavior although to a lesser degree, as shown by the open field test data. In conclusion, the present results indicate that sensorimotor stimulation applied during the period of fastest rate of cortical cytodifferentiation compensates for neuronal and behavioral impairment produced by undernutrition.

Animals↗
PubMed1996

[Are geoprocessing, environment, and health a possible combination?]

The use of geoprocessing techniques allows one to gather socioeconomic, health, and environmental data on a spatial basis. However, interpretation of associations between epidemiological and environmental variables requires the geoprocessing system design. The study scale and object choices precede conception of the system, conditioning the possible statistical and visual results. This scale must be compatible with the phenomenon on which one intends to focus, aiming at internal homogeneity and external heterogeneity of spatial units. The interdependency of spatial processes, reflected in the spatial configuration of social, environmental, and epidemiological data distribution, affects interpretation of causes for simultaneous processes. Geoprocessing allows for knowledge of the context or situational surroundings in which the damage to health takes place.

Journal Article↗
PubMed1999

Artificial selection on phenotypically plastic traits.

Many phenotypes respond physiologically or developmentally to continuously distributed environmental variables such as temperature and nutritional quality. Information about phenotypic plasticity can be used to improve the efficiency of artificial selection. Here we show that the quantitative genetic theory for 'infinite-dimensional' traits such as reaction norms provides a natural framework to accomplish this goal. It is expected to improve selection responses by making more efficient use of information about environmental effects than do conventional methods. The approach is illustrated by deriving an index for mass selection of a phenotypically plastic trait. We suggest that the same approach could be extended directly to more general and efficient breeding schemes, such as those based on general best linear unbiased prediction. Methods for estimating genetic covariance functions are reviewed.

Animals↗
PubMed1995

Genetic mediation in the relationship of education to cognitive function in older people.

We used data from 136 monozygotic and 125 dizygotic human, male twin pairs (M age = 64 years, range = 59 to 70 years) to test whether the previously observed association (r = .30, p < .01) between cognitive performance and education in this sample is genetically mediated. Biometric genetic modeling found that a common genetic latent variable accounted for 44% of the total variance in the Mini-Mental State Exam (MMSE: M. F. Folstein, S. E. Folstein, & P. R. McHugh, 1975), 40% of the variance in the Iowa Screening Battery for Mental Decline (P. J. Eslinger, A. R. Damasio, & A. L. Benton, 1984), and 21% of the variance in educational attainment. In addition, specific genetic and environmental variables contributed significantly to individual differences in education and cognitive performance of the participants.

Aged↗
PubMed2006

Global environmental data for mapping infectious disease distribution.

This contribution documents the satellite data archives, data processing methods and temporal Fourier analysis (TFA) techniques used to create the remotely sensed datasets on the DVD distributed with this volume. The aim is to provide a detailed reference guide to the genesis of the data, rather than a standard review. These remotely sensed data cover the entire globe at either 1 x 1 or 8 x 8 km spatial resolution. We briefly evaluate the relationships between the 1 x 1 and 8 x 8 km global TFA products to explore their inter-compatibility. The 8 x 8 km TFA surfaces are used in the mapping procedures detailed in the subsequent disease mapping reviews, since the 1 x 1 km products have been validated less widely. Details are also provided on additional, current and planned sensors that should be able to provide continuity with these environmental variable surfaces, as well as other sources of global data that may be used for mapping infectious disease.

Communicable Diseases↗
PubMed2000

Forecasting physicochemical variables by a classification tree method. Application to the Berre Lagoon (south France).

The dynamics of the "Etang de Berre", a brackish lagoon situated close to the French Mediterranean sea coast, is strongly disturbed by freshwater inputs coming from an hydroelectric power station. The system dynamics has been described as a sequence of daily typical states from a set of physicochemical variables such as temperature, salinity and dissolved oxygen rates collected over three years by an automatic sampling station. Each daily pattern summarizes the evolution, hour by hour of the physicochemical variables. This article presents results of forecasts of the states of the system subjected to the simultaneous effects of meteorological conditions and freshwater releases. We recall the main step of the classification tree method used to build up the predictive model (Classification and Regression Trees, Breiman et al., 1984) and we propose a transfer procedure in order to test the stability of the model. Results obtained on the Etang de Berre data set allow us to describe and predict the effects of the environmental variables on the system dynamics with a margin of error. The transfer procedure applied after the tree building process gives a maximum gain in prediction accuracy of about 15%.

Environmental Monitoring↗
PubMed2002

DNA microarrays and toxicogenomics: applications for ecotoxicology?

Toxicogenomics attempts to define how the regulation and expression of genes mediate the toxicological effects associated with exposure to a chemical. DNA microarrays are rapidly becoming one of the tools of choice for large-scale toxicogenomic studies. An approach in modern toxicogenomics has been to classify toxicity based on gene transcriptional patterns; comparing the transcriptional responses of a chemical with unknown toxicity to those for which the transcriptional profiles and toxicological endpoints have been well characterized. Recent evidence suggests that gene expression microarrays may be instrumental in defining mechanisms of action of toxicants. However, several assumptions are inherent to a toxicogenomic-based approach in toxicology, many of which remain to be validated. Gene expression profiling using DNA microarrays represents a snapshot of the gene transcriptional responses occurring at a particular time and within a particular tissue. Toxicity, on the other hand, represents a continuum of possible effects governed by both temporal and spatial factors that are inextricably contingent upon the exposure conditions. The perceived toxicological properties of any chemical are dependent on the route, dose, and duration of the exposure, and as such, gene expression patterns are also subject to these variables. Correct interpretation of DNA microarray data for the assessment of the toxicological properties of chemicals will require that temporal and spatial gene expression profiles be accounted for. These considerations are further compounded in ecotoxicological studies, during which altered gene expression patterns induced from exposure to an anthropogenic substance must be discernible over and above the complex effects that phenotypic, genotypic, and environmental variables have on gene expression. To this end, the greatest utility of DNA microarrays in the field of ecotoxicology may be in predicting the toxicological modes of action of anthropogenic substances on host physiology, particularly in non-model organisms. Predictable and accurate assessment of the impacts of a chemical substance in ecotoxicology will require that classical toxicological endpoints be used to validate any effects predicted based on gene expression profiling. Validated expression profiling may subsequently find utility in ecotoxicological-based computer simulation models, such as the Biotic Ligand Model (BLM), in which gene expression information may be integrated with geochemical, pharmacokinetic, and physiological data to accurately assess and predict toxicity of metals to aquatic organisms.

Journal Article↗
PubMed1984

Usefulness of the guppy, Poecilia reticulata, in carcinogenicity testing: special advantages and problems.

The guppy, Poecilia reticulata, native to fresh and brackish waters of northeastern South America and adjacent islands of the Caribbean, has been introduced throughout much of the tropical and subtropical world. It tolerates comparatively wide ranges of temperature, salinity, and crowding. This hardiness plus high fecundity, live birth, fast growth, and early maturation make it an excellent laboratory organism for disciplines ranging from behavioral studies to toxicity testing. In 4 published carcinogenicity studies, 8 of 11 known mammalian carcinogens produced neoplasms in the liver and occasionally at other sites. The guppy's overall popularity, however, has magnified problems concerning stock origin. The natural variability of this species has been increased by artificially selected breeding and by exotic natural selection pressures of foreign environments on introduced populations. The source of many guppy stocks today is ultimately the pet trade, and a good genetic history of such strains is not often available. Differences in stock origin may account for some differential responses of growth and sensitivity to environmental variables noted in the literature. The establishment of carefully maintained inbred strains for cancer research is the best solution to this problem.

Animals↗
PubMed2005

Balancing animal research with animal well-being: establishment of goals and harmonization of approaches.

A resource is provided for the creation of an institutional program that balances the scientific mission of an institution with the well-being of the animals used in support of the research. The concept of harmonizing scientific goals with animal well-being was first suggested in the early part of the twentieth century and later revitalized in the literature of the 1950s. Harmonization can best be achieved through the promotion of a team initiative. The team should include, at a minimum, the scientist, veterinarian, institutional animal care and use committee, and animal care staff. It is the responsibility of this animal research team to promote and balance the generation of scientifically valid data with animal well-being. The team must strive to minimize or eliminate non-protocol variables that could adversely affect the validity and repeatability of the experimental data. Good experimental design coupled with excellent communication between team members can often minimize or eliminate many variables and result in both better science and animal well-being. To ensure the scientific validity of experimental data, scientists must be aware of the complex nature of the environment in which their animals are maintained. To ensure repeatablity of an experiment, scientists must document and publish both the inanimate and social environments in which their animals are housed. Better documentation of environmental variables and their correlation with experimental results will promote critical knowledge about the relationships between an animal's environment, its well-being, and science.

Animal Experimentation↗
PubMed1984

Extensions to a technique for relating mortality and environment--exemplified by nasal cancer and industry.

The use of geographic data to interrelate mortality rates and environmental variables is an important approach to determining reasons for the variations in disease frequency. An alternative methodology to standard regression analysis was recently suggested, which is particularly useful when there are a large number of geographic areas and relatively few deaths. An extension of this technique is described, which includes a modified regression approach using areas aggregated according to their level of the environmental factor. An example is given relating nasal cancer mortality to the distribution of industry in England and Wales. The known hazards in the furniture and leather industries are indicated and other potential risk industries, including tailoring, are suggested.

England↗
PubMed2004

Visibility of the impact of environmental noise: a response to Kaitala and Ranta.

Based on simulation modelling, Kaitala and Ranta (2001 Proc. R. Soc. Lond. B 268, 1769-1774) have argued that detecting the statistical relationships between environmental variability and population fluctuations will be difficult. However, their study was limited in that only one pattern of density dependence and one detection method were used. Here, we show that their conclusion is in part a consequence of their choice of population model and in part a consequence of using relatively weak or inappropriate statistical methods. Other patterns of density dependence respond differently to environmental fluctuations, and the impact of the disturbance on these is clearly visible using their methods. For some patterns of population dynamics, environmental impacts are more readily detectable by correlating running-average environmental conditions with the population time-series or by correlating the first differences of the population time-series with environmental noise. When more appropriate statistical methods are used, environmental forcing is detectable in the majority of cases used by Kaitala and Ranta. The interplay between environmental stochasticity and density-dependent population growth means that there is no single best method to detect the influence of environmental forcing, even when population dynamics are approximately linear. But environmental forcing will often be detectable, contrary to Kaitala and Ranta's assertions.

Age Factors↗
PubMed1989

Exposure to lead and cadmium of children living near a lead smelter at Lavrion, Greece.

Exposure of children of the Greek town of Lavrion to lead and cadmium has been evaluated by determination of the levels of lead (PbB) and cadmium (CdB) in the blood of 514 children living in the town. The Lavrion area is heavily polluted by lead owing to the presence of a large lead-zinc mining and smelting industrial complex. The industrial PbB level (geometric mean) was 21.7 micrograms dl-1 (range 7.4-79.8 micrograms dl-1). The CdB levels were, on average, 0.36 micrograms l-1 (range 0.1-3.1 micrograms l-1). The results were evaluated with respect to a number of constitutional, social and environmental variables, such as age, gender, distance of the school from the lead-zinc mining and smelting complex, and occupation and education of the father.

Age Factors↗
PubMed2005

Water quality and breeding habitats of anopheline mosquito in northwestern Thailand.

Malaria transmission is dependent upon many hydrology-driven ecological factors that directly affect the vectorial competence, including the presence of suitable habitats for the development of anopheline larvae. Larval habitats were identified and characterized at three malaria endemic villages (Ban Khun Huay, Ban Pa Dae, and Ban Tham Seau) in Mae Sot district, Tak Province, in northwestern Thailand between July 2002 and June 2003. The Global Positioning System (GPS) was used to provide precise locational data for the spatial distribution of anopheline mosquito larvae and their habitats. Ten habitat categories were identified. Eighteen adult Anopheles species were identified from larvae in all the surveyed habitats. An. minimus was the most common species throughout the year. The relationship between eight abiotic variables (temperature, hardness, carbon dioxide, dissolved oxygen, nitrate, phosphate, silica and pH) and the abundance of four major species of malaria vectors (An. (Cel.) dirus, An. (Cel.) minimus, An. (Cel.) maculatus, and An. (Cel.) sawadwongporni), and six species of non-vectors (An. (Cel.) kochi, An. (Cel.) jamesii, An. (Ano.) peditaeniatus, An. (Ano.) barbirostris, An. (Ano.) campestris, and An (Cel.) vagus) larvae was investigated. The results from the multiple regression models suggest that hardness, water temperature and carbon dioxide are the best predictor variables associated with the abundance of An. minimus larvae (p < 0.001); water pH for An. dirus larvae (p < 0.001); temperature and pH for An. kochi larvae (p < 0.01); temperature and silica concentration for An. jamesii larvae (p < 0.001); dissolved oxygen and silica concentration for An. campestris larvae (p < 0.001); and pH and silica concentration for An. vagus larvae (p < 0.001). We could not identify key environmental variables for An. maculatus, An. sawadwongporni, An. peditaeniatus, and An. barbirostris.

Animals↗
PubMed1997

[Adiposity and fat distribution in preschool children from low socioeconomic levels in Caracas].

Epidemiological studies suggest that body fat distribution in adults is associated with chronical nontransmissible diseases, less is known during the growing years. The current study was undertaken to explore the relationship between level of fatness, fat patterning and some socioenvironmental variables in a group of 449 children aged 3 to 6, living in Caracas, who belong to the poorest Venezuelan socio-economic stratum. Data was analyzed taking nutritional status (weight-for-age), an index of socioeconomic conditions (ICSA), sex and age, as control variables. Using a multivariate analysis we derived first, two groups of households (G1 and G2) as determined by socioeconomic variables, to which principal component analysis was applied to elicited fatness and relative fat patterning through six skinfolds. First component identify level of adiposity, second extremity/trunk fatness, and third upper/lower pattern. Comparison of normal children with those of low weight-for-age showed differences in adiposity and in the upper/lower patterning as detected by the skinfolds involved in the differences: subscapular (-0.53) and supraspinale (0.32) in children with low weight-for-age; triceps (-0.46) and thigh (0.29) in those classified as normal. We found that gender, nutritional condition, environmental variables and age, were significant predictors of the differences in adiposity level; while age and households conditions, appear to be related to upper/lower patterning. The data equally suggests that body fat is more centrally distributed in boys with low weight-for-age. Since these patterns are indicators of risk in the ongoing years, we call tha attention about environmental circumstances.

Adipose Tissue↗
PubMed1975

Cancer of the colon: socioeconomic variables in a community.

Carcinoma of the colon was studied in Omaha-Douglas County, Nebraska (population 345,000). A total of 154 cases of colon cancer were diagnosed in 1964 (44.7/100,000). The frequency distribution of these patients in specific census tracts of this community was determined. Statistical analysis of the data showed a greater frequency of colon cancer in patients living in census tracts with higher average income. Colon cancer appears to be nonrandomly distributed with respect to the income and socioeconomic status of its victims, suggesting that hypotheses consistent with environmental variables--particularly those characterizing extremely high versus extremely low socioeconomic groups, including occupation, diet and other life patterns--should be pursued. All of these data have implications for cancer epidemiology, cancer control, and carcinogenesis.

Adult↗