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Environmental and behavioral factors that can affect blood pressure.

A patient's blood pressure may vary considerably and not be a sign of a pathological process in the patient. Environmental factors which cause blood pressure changes are climate, temperature and time of day. There are also age and sex differences in blood pressure. Body and extremity position, activity and exercise, food, tobacco and alcohol consumption, and psychological stress are behavioral factors which alter blood pressure. When the nurse practitioner measures a patient's blood pressure, as many transient variables as possible need to be controlled. Those factors which cannot be controlled must be carefully evaluated so the NP does not erroneously interpret the blood pressure change as a sign of pathology.

Adolescent↗

Potential impact of acid precipitation on arsenic and selenium.

The potential impact of acidic precipitation on the environmental mobility of the metalloids arsenic (As) and selenium (Se) has not been given much attention and is poorly understood. As with other elements, the interest here is the potential effect of environmental acidification on environmental behavior in ways that are relevant to human exposure to these metalloids. Available information on acid precipitation and the environmental behavior of these metalloids do, however, permit some preliminary conclusions to be drawn. Both As and Se appear to be mobilized from household plumbing into tap water by the corrosive action of soft, mildly acidic water, while surface water catchment systems in areas impacted by acidic deposition may contain elevated soluble As levels. Acidification of aquatic ecosystems that are drinking water sources may pose the prospect of enhanced release of As from sediment to water as well as reduction in water levels of Se. Acidification of ground waters, where As appears to be especially mobile, is of particular concern in this regard. The potential impact of acidic deposition on As and Se in soils cannot readily be assessed with respect to human exposure, but it would appear that the behavior of these metalloids in poorly buffered, poorly immobilizing soils, e.g., sandy soils of low metal hydrous oxide content, would be most affected. The effect is opposite for the two elements; lowered pH would appear to enhance As mobility and to reduce Se availability. Altered acidity of both soil and aquatic systems poses a risk for altered biotransformation processes involving both As and Se, thereby affecting the relative amounts of different chemical forms varying in their toxicity to humans as well as influencing biogeochemical cycling.

Acids↗

Air-water transfer of MTBE, its degradation products, and alternative fuel oxygenates: the role of temperature.

The gasoline oxygenate methyl tert-butyl ether (MTBE) has become one of the world's mostwidespread groundwater and surface water contaminants. As a result, there has been increasing interest in the environmental behavior of MTBE and its degradation products, mainly tert-butyl formate (TBF) and tert-butyl alcohol (TBA). In contrast, the environmental behavior of the proposed alternatives to MTBE, namely ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and diisopropyl ether (DIPE) has hardly been studied yet, although some of them are already in substantial use in various countries. A key parameter for the assessment of the fate, transport, and possible remediation of these contaminants is the air-water partitioning constant (KiH). The KiH is highly temperature dependent, and it is therefore necessary to obtain reliable experimental values at relevant temperatures. Hence, the KiH of MTBE, ETBE, TAME, and DIPE, along with the degradation products, TBF and methyl acetate, were determined from 5 degrees C-40 degrees C. The alternatives to MTBE generally had a higher KiH, which implies that, upon emission into the environment, the alternatives partition more readily into the air phase than MTBE. This may favor their use, as it is in the air phase where dilution and degradation are the most effective. The degradation products of MTBE, with the exception of TBF, have much lower KiH values at all temperatures. Hence, the degradation products will have a stronger affinity for the water phase. The temperature dependency of the kinetics of air-watertransfer is discussed using a boundary layer model. Only for TBA but not for the ethers a significant effect of temperature was found.

Acetates↗

Epidemiology of cutaneous leishmaniasis in Colombia: environmental and behavioral risk factors for infection, clinical manifestations, and pathogenicity.

Through a longitudinal, active surveillance for Leishmania (Viannia) braziliensis and Leishmania (Viannia) panamensis infection and lesions on the Pacific Coast of Colombia, risk factors for infection (leishmanin skin test conversion), leishmanial lesions, and pathogenicity were examined. Risk factor information was obtained prior to and independently of case ascertainment. Similar factors were associated with acquisition of infection and of leishmaniasis, including male sex, age > 10 years, and farming occupation. The behaviors of entering the forest after sunset, hunting, and lumbering were most strongly associated with Leishmania infection independently of age, sex, and farming occupation. Environmental conditions associated with infection, including tall trees near the home, home located > 15 m from the nearest neighbor, and floor and roof made of open material, were less strong predictors of risk. Pathogenicity, the risk of lesion given a new infection, was reduced in those > 30 years of age and those entering the forest frequently.

Adolescent↗

[Research advances in behavioral ecology of penaeid shrimp II. Effects of environmental factors on behavior of penaeid shrimps].

Animal has an extrinsic response to the changes of internal and external environments. To ensure the stabilization of internal environment, animal should adjust its behavior to conform the changes of external environmental factors. This paper reviewed the research advances at home and abroad on the effects of environmental factors on the behavior of penaeid shrimps, with the focus on the effects of light, current and tide, dissolved oxygen, substrate, and water temperature on the feeding, locomotion, spawning, moulting, burrowing and emergence of penaeid shrimps. The behavioral adjustment of penaeid shrimps to the changes of environmental factors was also summarized. The existing problems and future research directions in the behavioral ecology of penaeid shrimps, e.g., the relationships between penaeid shrimps behavior and disease spread, effects of penaeid shrimps behavior on aquaculture ecosystem, and effects of environmental factors on penaeid shrimps behavior in intensive and high-density culture, were put forward.

Adaptation, Physiological↗

Several antecedent strategies in reduction of an environmentally destructive behavior.

The effects of response-specific prompts, prompts identifying long-term and short-term consequences, a combination of long-term and short-term consequences, and a combination of short-term consequences and response-specific prompts on the reduction of environmentally destructive lawn-walking were investigated. The response-specific prompt alone was effective, and its effectiveness was enhanced by the identification of short-term and long-term consequences; however, the mere identification of short-term and long-term consequences alone was not effective.

Behavior Therapy↗

[Perceived health and pregnancy: study of several behavioral and environmental determinants among a population of pregnant women].

The aim of this study, based on data of the Centre for Preventive Medicine, is to compare the perceptions women have of their health within a population of pregnant women that was divided into two categories: one group of women who feel they are in a poor health, the others feel they are in good health. The study results seem to differentiate between both the psychological and physical profiles of the two groups of pregnant women. The women who are not followed by a doctor don't seem to have a more negative perception of their health status. It seems, in addition, that the negative perception of health status has not only psychological roots, but also behavioural and environmental ones.

Adolescent↗

Environmental and behavioral determinants of fasting plasma glucose in women. A matched co-twin analysis.

Comparing results of an unmatched analysis in a sample of unrelated persons created by randomly selecting one twin from each pair with results of a matched monozygotic co-twin analysis provides a means of distinguishing environmental influences from genetic influences on a dependent variable of interest. Determinants of the fasting plasma glucose level were investigated in a large sample of adult female nondiabetic twins from the Kaiser Permanente Twin Registry. In the subsample of unrelated persons, fasting plasma glucose was significantly and positively associated with age, body mass index, uric acid level, and alcohol intake and was significantly inversely related to leisure time physical activity. When monozygotic twins were treated as matched pairs, only the effects of body mass index and alcohol consumption remained significant, whereas the association with leisure time physical activity was greatly reduced and no longer statistically significant. These results suggest that behavioral and therefore alterable aspects of obesity and alcohol consumption influence the fasting plasma glucose level; alcohol consumption may be a risk factor for non-insulin-dependent diabetes mellitus; and common underlying genetic factor(s) may be responsible for the negative association between physical activity and fasting plasma glucose.

Adult↗

Individualized behavioral and environmental care for the very low birth weight preterm infant at high risk for bronchopulmonary dysplasia: neonatal intensive care unit and developmental outcome.

We hypothesize that the respiratory and functional states of the very low birth weight infant with bronchopulmonary dysplasia can be improved in the neonatal intensive care unit by prevention of inappropriate sensory input. To test this hypothesis, we developed for preterm newborns a behavior observation method that catalogues specific reaction patterns according to putative stress and relaxation behaviors. We then collected behavioral information and heart rate, respiratory rate, and transcutaneous PO2 readings before, during, and after routine care-giving interventions. Eight control and eight experimental infants were selected for study based on the following criteria: birth weight less than 1,250 g, gestational age less than 28 weeks, on the respirator greater than 24 hours in first 48 hours of life at greater than or equal to 0.60 FiO2 for more than two hours during first 48 hours of life. Additionally, the two groups were comparable on other medical and demographic variables, including severity of respiratory status for the first ten days and incidence of intraventricular hemorrhage, patent ductus arteriosus, and socioeconomic status. Systematic observations were conducted on days 10, 20, and 30 after birth and at 36 and 40 weeks postconception. For the intervention infants, our observations were discussed with the infants' primary nurses, and individualized modifications for each infant's care plan were implemented based on these observations. Experimental infants showed significantly briefer stays on the respirator (P less than .01) and in increased FiO2 (P less than .05). Their feeding behavior was normalized significantly earlier (P less than .01). Experimental infants also showed significantly better behavioral regulation scores at 1 month after their mothers' estimated dates of confinement (post-EDC), as measured with the Assessment of Preterm Infants' Behavior, significantly better Mental and Psychomotor Developmental Indices at 3, 6, and 9 months post-EDC, as measured with the Bayley Scales of Infant Development, and significantly better behavioral regulation scores at 9 months post-EDC, as measured in a videotaped play observation. Measurements of weight, height, and head circumference at 3, 6, and 9 months post-EDC showed no differences. All assessments were performed by one of two trained testers not familiar with the goals of the study or the group status of the infant. These results support the hypothesis that very low birth weight preterm babies profit significantly both medically and developmentally from individualized behavioral care in the neonatal intensive care unit.

Bronchopulmonary Dysplasia↗

Normally occurring environmental and behavioral influences on gene activity: from central dogma to probabilistic epigenesis.

The central dogma of molecular biology holds that "information" flows from the genes to the structure of the proteins that the genes bring about through the formula DNA-->RNA-->Protein. In this view, a set of master genes activates the DNA necessary to produce the appropriate proteins that the organism needs during development. In contrast to this view, probabilistic epigenesis holds that necessarily there are signals from the internal and external environment that activate DNA to produce the appropriate proteins. To support this view, a substantial body of evidence is reviewed showing that external environmental influences on gene activation are normally occurring events in a large variety of organisms, including humans. This demonstrates how genes and environments work together to produce functional organisms, thus extending the author's model of probabilistic epigenesis.

Behavior↗

Behavioral and environmental determinants of reproductive success in traditional Moroccan Berber groups.

The reproductive histories of women aged 45-70 years from a homogeneous Berber population of South Morocco were sampled from three contrasting environments: a small town (n = 75), villages in the lowlands (n = 217), and villages in the highlands (n = 128). The main reproductive variables oppose the relatively better conditions of fertile life in the lowlands to the more hostile ones in the highlands. Path analysis confirms this difference through reproductive behaviors and suggests the existence of mechanisms for controlling family size in town and in the rural lowlands, but not in the highlands. The estimates of survival function show significant differences among the three groups, the conditions for survival in the highlands being clearly less favorable. Rank tests of the association of survival data with several covariates indicate the association of survival data with vaccinations and with conditions of delivery. In spite of the lower rate of offspring survival, the highlander group would demonstrate a higher overall number of children reaching reproductive maturity, thanks to an extended reproductive span.

Aged↗

Genetic, behavioral and environmental determinants of male longevity in Caenorhabditis elegans.

Males of the nematode Caenorhabditis elegans are shorter lived than hermaphrodites when maintained in single-sex groups. We observed that groups of young males form clumps and that solitary males live longer, indicating that male-male interactions reduce life span. By contrast, grouped or isolated hermaphrodites exhibited the same longevity. In one wild isolate of C. elegans, AB2, there was evidence of copulation between males. Nine uncoordinated (unc) mutations were used to block clumping behavior. These mutations had little effect on hermaphrodite life span in most cases, yet many increased male longevity even beyond that of solitary wild-type males. In one case, the neuronal function mutant unc-64(e246), hermaphrodite life span was also increased by up to 60%. The longevity of unc-4(e120), unc-13(e51), and unc-32(e189) males exceeded that of hermaphrodites by 70-120%. This difference appears to reflect a difference in sex-specific life span potential revealed in the absence of male behavior that is detrimental to survival. The greater longevity of males appears not to be affected by daf-2, but is influenced by daf-16. In the absence of male-male interactions, median (but not maximum) male life span was variable. This variability was reduced when dead bacteria were used as food. Maintenance on dead bacteria extended both male and hermaphrodite longevity.

Animals↗