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PubMed1981

Predicting adaptive functioning among mentally ill persons in community settings.

Attempts to improve instrumental role performance among mentally ill persons have traditionally focused on the modification of individual level variables. Recent interest in environmental-behavioral linkages, however, has led to attempt to isolate environmental variables which are both readily manipulable and significantly related to improved instrumental role performance. The present study examines the impact of a variety of individual, residential, and community variables on instrumental role performance using multiple regression analysis. The 10 variables in the equation had a multiple r of .77 with total score on the Residential portion of the Adaptive Functioning Index, indicating that they account for 60% of the variance in scores. Individual level variables account for 3% of the variance, while environmental variables, primarily those related to normalization account for 57% of the variance. The data suggest that environmental normalization may be an effective technology as well as an ideology.

Adaptation, Psychological↗
PubMed2000

Nonshared environment: a theoretical, methodological, and quantitative review.

When genetic similarity is controlled, siblings often appear no more alike than individuals selected at random from the population. Since R. Plomin and D. Daniels' seminal 1987 review, it has become widely accepted that the source of this dissimilarity is a variance component called nonshared environment. The authors review the conceptual foundations of nonshared environment, with emphasis on distinctions between components of environmental variance and causal properties of environmental events and between the effective and objective aspects of the environment. A statistical model of shared and nonshared environmental variables is developed. A quantitative review shows that measured nonshared environmental variables do not account for a substantial portion of the nonshared variability posited by biometric studies of behavior. Other explanations of the preponderance of nonshared environmental variability are suggested.

Animals↗
PubMed1991

Associations of daily mortality and air pollution in Los Angeles County.

We report results of a multiple regression analysis examining associations between aggregate daily mortality counts and environmental variables in Los Angeles County, California for the period 1970 to 1979. Mortality variable included total deaths not due to accidents and violence (M), deaths due to cardiovascular causes (CV), and deaths due to respiratory causes (Resp). The environmental variables included five pollutants averaged over Los Angeles County--total oxidants (Ox), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and KM (a measure of particulate optical reflectance). Also included were three metereological variables measured at the Los Angeles International Airport--temperature (Temp), relative humidity (RH), and extinction coefficient (Bext), the latter estimated from noontime visual range. To reduce the possibility of spurious correlations arising from the shared seasonal cycles of mortality and environmental variables, seasonal cycles were removed from the data by applying a high-pass filter. Cross-correlation functions were examined to determine the lag structure of the data prior to specifying and fitting the multiple regression models relating mortality and the environmental variables. The results demonstrated significant associations of M (or CV) with Ox at lag 1, temperature, and NO2, CO, or KM. Each of the latter three variables were strongly associated with daily mortality but also were highly correlated with one another in the high-frequency band, making it impossible to uniquely estimate their separate relationships to mortality. The results of this study show that small but significant associations exist in Los Angeles County between daily mortality and three separate environmental factors: temperature, primary motor vehicle-related pollutants (e.g., CO, KM, NO2), and photochemical oxidants.

Air Pollutants↗
PubMedDate not supplied

Environmental correlates of physical activity in a sample of Belgian adults.

PURPOSE: This study investigated the variance in sitting, walking, and moderate and vigorous physical activity explained by neighborhood design and recreational environmental variables above and beyond the variance accounted for by individual demographic variables. DESIGN: Cross-sectional analyses of self-reported survey data. SETTING: A random sample of inhabitants of Ghent, Belgium, aged 18-65 years, was drawn. SUBJECTS: Five hundred twenty-one adults completed questionnaires (52.1% response rate). The average age of the sample was 41 years, and 48.2% were female. MEASURES: A questionnaire developed to assess neighborhood design and recreational environmental variables with a total of 81 items was administered. The environmental questionnaire showed acceptable to good reliability and acceptable validity. The previously validated International Physical Activity Questionnaire (IPAQ) was used to quantify physical activity in the past 7 days. Additional demographic information was also obtained. RESULTS: Regression analyses showed that environmental variables were related to all types of physical activity in both sexes. However, the range of variance explained by the models including demographic and environmental variables was low, only 5% to 13%. Minutes of walking and of moderate-intensity activity were related to quality of sidewalks and accessibility of shopping and public transportation. Vigorous physical activity was related to presence of activity supplies in the home and number of convenient activity facilities outside the home. CONCLUSIONS: Both neighborhood design and recreational environment variables had small but significant associations with multiple types of physical activity in a sample of Belgian adults.

Adolescent↗
PubMed2003

Factors affecting the distribution of benthic macrofauna in estuaries contaminated by urban runoff.

Contaminants derived from urban runoff have been shown to accumulate in estuarine sediments, reaching concentrations potentially capable of causing biological effects. Demonstration of effects, however, is difficult due to strong natural environmental gradients and the effects of past or present point-sources of contamination. We used multivariate methods to test two hypotheses relating to the effects of urban-derived contaminants on estuarine benthic communities. First, that patterns of distribution and abundance of benthic invertebrates in two urbanised estuaries would be different from those in two non-urbanised estuaries. Second, that the distributions of benthic invertebrates within and among the four estuaries would be related to those of urban-derived contaminants. Concentrations of contaminants were larger in estuaries with urbanised catchments and concentrations of Cu, Pb, Zn and DDT in some samples exceeded those at which biological effects may be expected to appear. Tests of differences in composition of benthic communities among estuaries showed that the two urban estuaries were not significantly different, but that they differed from both rural estuaries, which also differed from each other. Distributions of benthic invertebrates were significantly related to those of environmental variables, and were ordinated along axes that correlated with both natural environmental variables (nature of the sediment, position in estuary) and contaminants. Differences in faunas between the urban and non-urban estuaries were not, however, clear-cut and nor were relationships between faunal assemblages and environmental variables (including contaminants) consistent between two times of sampling.

Animals↗
PubMed2004

Measuring the effects of an ever-changing environment on malaria control.

The effectiveness of malaria control measures depends not only on the potency of the control measures themselves but also upon the influence of variables associated with the environment. Environmental variables have the capacity either to enhance or to impair the desired outcome. An optimal outcome in the field, which is ultimately the real goal of vaccine research, will result from prior knowledge of both the potency of the control measures and the role of environmental variables. Here we describe both the potential effectiveness of control measures and the problems associated with testing in an area of endemicity. We placed canaries with different immunologic backgrounds (e.g., naïve to malaria infection, vaccinated naïve, and immune) directly into an area where avian malaria, Plasmodium relictum, is endemic. In our study setting, canaries that are naïve to malaria infection routinely suffer approximately 50% mortality during their first period of exposure to the disease. In comparison, birds vaccinated and boosted with a DNA vaccine plasmid encoding the circumsporozoite protein of P. relictum exhibited a moderate degree of protection against natural infection (P < 0.01). In the second year we followed the fate of all surviving birds with no further manipulation. The vaccinated birds from the first year were no longer statistically distinguishable for protection against malaria from cages of naïve birds. During this period, 36% of vaccinated birds died of malaria. We postulate that the vaccine-induced protective immune responses prevented the acquisition of natural immunity similar to that concurrently acquired by birds in a neighboring cage. These results indicate that dominant environmental parameters associated with malaria deaths can be addressed before their application to a less malleable human system.

Animals↗
PubMedDate not supplied

Measurement of growth variability and environmental quality in Guatemalan children.

The measurement of within-population growth variability may be a sensitive indicator of environmental quality. Specifically, it is hypothesized that within-population variability will increase in adverse environments. To evaluate this hypothesis the variability in stature growth of three samples of Guatemala school children (5-10 years old) is assessed. These samples include high socioeconomic status (SES) ladinos (84 boys and 98 girls) and low SES ladinos (136 boys and 101 girls) living in Guatemala City and very low SES Mayan Indians (139 boys and 73 girls) living in a rural town near the city. SES is used as a proxy for environmental quality. The coefficient of variation (CV) for distance achieved at each age, or for the increment of growth from age to age, is used as the measure of variability. The three samples differ significantly for variability in stature growth, both for the distance and the increments of growth. Low SES urban ladinos have the largest variability. Very low SES Mayan children have coefficients of variation that are sometimes equal to, and sometimes either larger or smaller than, CVs for the high SES ladinos. The results show that degree of environmental adversity does not correlate uniformly with growth variability. Factors such as rates of infant and early childhood mortality and the greater heterogeneity of the low SES urban environment, compared with the high SES urban or low SES rural environments, may account for differences in the CV in these three samples.

Child↗
PubMed2003

Ordination and classification of macroinvertebrates and environmental data of a stream in Turkey.

Macroinvertebrate communities and environmental variables were assessed in an Ankara Stream receiving high organic and industrial wastes. Environmental data were used to explain biological variation using multivariate techniques provided by the program CANOCO. The ordination method CCA (Canonical Correspondence Analysis) was applied to evaluate the relationships between environmental variables and distribution of macroinvertebrate genera. Data sets were classified by TWINSPAN (Two Way Indicator Species Analysis). In this investigation, macroinvertebrate communities have been shown by CCA ordination to be related to TOM (total organic matter), ammonia, cadmium, pH, lead, dissolved oxygen, conductivity (EC), phosphate, boron, nitrite and hardness, with TOM, ammonia, cadmium and pH emerging as the most significant environmental variables. Epeorus was a TWINSPAN indicator for the slightly polluted upstream site 1. Physa was a TWINSPAN indicator for the polluted downstream sites.

Animals↗
PubMed1999

The nursing home at night: effects of an intervention on noise, light, and sleep.

OBJECTIVES: The sleep of nursing home residents is fragmented by frequent awakening episodes associated, at least in part, with environmental variables, including noise and light changes. The purpose of this study was to improve sleep by reducing the frequency of nighttime noise and light changes. PARTICIPANTS AND SETTING: Two hundred sixty-seven incontinent nursing home residents in eight nursing homes. DESIGN: A randomized control group design with a delayed intervention for the control group. MEASUREMENTS: Bedside noise and light monitors recorded the number of 2-minute intervals at night with peak sounds recorded above 50 dBs and the number of light changes of at least 10 lux between adjacent 2-minute intervals. Daytime behavioral observations measured sleep and in-bed time during the day, and wrist activity was used to estimate sleep at night. Awakening events associated with the environmental variables were derived from the wrist activity data. INTERVENTION: A behavioral intervention implemented between 7:00 p.m. and 6:00 a.m. that involved feedback to nursing home staff about noise levels and implementation by research staff of procedures to both abate noise (e.g., turn off unwatched television sets) and to individualize nighttime incontinence care routines to be less disruptive to sleep. RESULTS: Noise was reduced significantly, from an average of 83 intervals per night with peak noises recorded above 50 dBs to an average of 58 intervals per night in the group that received the initial intervention, whereas noise in the control group showed no change (MANOVA group x time P < .001). All 10-dB categories of noise from 50 to 90+ dBs were reduced, and light changes were reduced from an average of four per night per resident to two per night (P < .001). Despite these significant changes in the environmental variables, there was a significant differential improvement in the intervention group on only two night sleep measures: awakening associated with a combination of noise plus light (P < .001) and awakening associated with light (P < .001). However, there was a significant correlation between change in noise and change in percent sleep from baseline to intervention (r = -.29, P < .05), suggesting that the intervention did not reduce noise to low enough levels to produce a significant improvement in sleep. The intervention effects on all environmental variables were replicated in the delayed intervention group, who again showed significant improvement on the same sleep measures. Observations of day sleep and in-bed time did not change over the phases of the trial for either group. CONCLUSION: The significant reductions in noise and light events resulting from the intervention did not lead to significant improvements in the day sleep and most night sleep measures. An intervention that combines both behavioral and environmental strategies and that addresses daytime behavioral factors associated with poor sleep (e.g., excessive time in bed) would potentially be more effective in improving the night sleep and quality of life of nursing home residents.

Aged↗
PubMed1998

Cotinine excretion as a predictor of peak flow variability.

Environmental tobacco smoke (ETS) is suspected to be an important risk factor for bronchial hyperresponsiveness. In order to test the effect of ETS, we measured expiratory flow rates and urine cotinine excretion (UCE) within a narrow time window in two consecutive years. Maternal smoking habits and medical history were ascertained by standardized questionnaires. The percentage ratio of the amplitude over the mean (AVAM) of the diurnal peak flow rates of children (complete values from at least five consecutive days) was calculated as an indicator of bronchial responsiveness. The association of UCE and log10AVAM was analyzed by multiple linear regression. Complete data were available for a sample of 417 children. The median of UCE in children of parents who smoked (3.2 ng/mg and 2.9 ng/mg creatinine, Surveys 1 and 2, respectively) was higher than the median in children of nonsmoking parents (0 ng/mg in both surveys). With increasing UCE the log10AVAM rose in the first and second surveys, as well as in the longitudinal analysis (p = 0.003). This association, however, showed up only in boys (p = 0.0001) and not in girls (p = 0.31). Our data suggest that there is a need both for further analysis of the gender difference and for more support of strategies against passive smoking as far as children are concerned, since airway hyperresponsiveness is a risk factor for chronic airway impairment.

Asthma↗
PubMedDate not supplied

Maximum expiratory flow-volume curves in children: changes with growth and individual variability.

Environmental factors may affect the lungs of children by retarding growth of ventilatory capacity. To detect retarded growth, we recorded maximum expiratory flow-volume (MEFV) curves in boys and girls aged 8-14 years observing the normal patterns of growth. The accuracy with which deviations from the normal patterns of growth may be measured was also determined. Expiratory flow rates and timed expiratory volumes were less reproducible in the same child than was forced vital capacity. At all ages the shape of girls' MEFV curves was different from that of boys curves in that girls had greater maximum expiratory flow rates (Vmax.) when differences in forced vital capacity (FVC) had been taken into account. The ratio of Vmax. 50% FVC to FVC decreased in both boys and girls as they grew older. The rates of growth of the MEFV curve measurements and estimates of their reproducibility were used to calculate minimum sample sizes required to detect retarded growth of ventilatory capacity. To detect a change of 10% in the normal growth rate in Vmax. 50% FVC between ages 8 and 14 years, nearly 2,000 children would need to be studied annually. Smaller samples could be used if changes in FVC growth rates were of primary concern.

Adolescent↗
PubMed2001

Associations between self-reported and objective physical environmental factors and use of a community rail-trail.

BACKGROUND: To effectively promote physical activIty, researchers and policy makers have advocated for greater use of environmental approaches, such as the construction of community paths and trails. However, research on the use of these facilities is limited. METHODS: In this cross-sectional community study, we examined associations between self-reported and objective physical environmental variables and use of the Minuteman Bikeway (Arlington, MA) in a random sample of 413 adults. Sociodemographic and perceived environmental variables were measured with a mail survey during September 1998. Geographic information system (GIS) data were used to geocode survey respondents' homes and create three objective environmental variables: distance to the Bikeway, steep hill barrier, and a busy street barrier. RESULTS: In logistic models, age and female gender showed statistically significant inverse associations with Bikeway use over the previous 4-week period. Increases in self-reported (OR = 0.65) and GIS distance (OR = 0.57) were associated with decreased likelihood of Bikeway use. Absence of self-reported busy street (OR = 2.01) and GIS steep hill barriers (OR = 1.84) were associated with Bikeway use. CONCLUSIONS: Environmental barriers such as travel distance and hilly terrain should be considered when planning community trails. A better understanding of such factors may lead to more effective promotion of trail use.

Adult↗
PubMed2004

Specialization and habitat: spatial and environmental effects on abundance and genetic diversity of forest generalist and specialist Carabus species.

Habitat specialist species are supposed to be more susceptible to variations in local environmental characteristics than generalists. To test this hypothesis, we conducted a comparative analysis on abundance and genetic diversity of forest carabids differing in their habitat requirements. Four species were sampled in forests characterized by abiotic, landscape and biotic environmental variables. A statistical framework based on canonical correspondence analysis was used for one habitat generalist and one habitat specialist species to determine the relative contribution of environmental variables in structuring inter- and intrapopulational genetic diversity depicted by microsatellites. Our results showed that sympatric species differed in their sensitivity to environmental variables. The same variables were found to be important in analyses of abundance and genetic data. However, specialization was not related to a greater sensitivity to local environmental characteristics. The strong impact of spatial variables on genetic data suggested that genetic variation among populations would largely reflect the response of individual species to dispersal opportunities more than the effect of habitat quality.

Adaptation, Biological↗
PubMed1990

A third component causing random variability beside environment and genotype. A reason for the limited success of a 30 year long effort to standardize laboratory animals?

This paper is a review of experiments, performed in our laboratory during the past 20 years, designed to analyse the significance of different components of random variability in quantitative traits in laboratory rats and mice. Reduction of genetic variability by using inbred strains and reduction of environmental variability by highly standardized husbandry in laboratory animals did not remarkably reduce the range of random variability in quantitative biological traits. Neither did a tremendous increase of the environmental variability (i.e., living in a natural setting) increase it. Therefore, the postnatal environment cannot be that important as the source of random variability. Utilizing methods established in twin research, only 20-30% of the range of the body weight in inbred mice were directly estimated to be of environmental origin. The remaining 70-80% were due to a third component creating biological random variability, in addition to the genetic and environmental influences. This third component is effective at or before fertilization and may originate from ooplasmic differences. It is the most important component of the phenotypic random variability, fixing its range and dominating the genetic and the environmental component. The Gaussian distribution of the body weights observed, even in inbred animals, seems to be an arrangement supporting natural selection rather than the consequence of heterogeneous environmental influences. In a group of inbred rats, the males with the highest chance of parenting the next generation were gathered in the central classes of the distribution of the body weight.

Animal Husbandry↗
PubMed1974

Niche overlap and diffuse competition.

Current theory predicts a distinct upper limit on the permissible degree of niche overlap; moreover, theory suggests that maximal tolerable overlap should be relatively insensitive to environmental variability. Data presented here demonstrate that, within the lizard subset of natural desert communities, niche overlap decreases both with increasing environmental variability and with increasing numbers of lizard species. The latter two factors are themselves positively correlated. A partial correlation analysis is interpreted as indicating that the extent of tolerable niche overlap does not necessarily decrease due to environmental variability, but rather that overlap is probably more closely related to the number of potential interspecific competitors in a community, or what has been termed "diffuse competition." This result lends support to the "niche overlap hypothesis," which asserts that maximal tolerable overlap should vary inversely with the intensity of competition. Moreover, this empirical discovery indicates that niche overlap theory could be profitably expanded to incorporate the number of competing species. Although the average amount of overlap between pairs of species decreases with the intensity of diffuse competition, the overall degree of competitive inhibition tolerated by individuals comprising an average species could nevertheless remain relatively constant, provided that extensive niche overlap with a few competitors is roughly equivalent to lower average overlap with a greater number of competitors.

Animals↗
PubMed1992

Infants with myelomeningocele: visual recognition memory and sensorimotor abilities.

The cognitive development was explored of 29 infants with myelomeningocele. Although as a group they tended to be less likely to demonstrate visual recognition memory than a matched control group, excluding the more severely cognitively impaired infants from analysis rendered this difference non-significant. Infants with myelomeningocele demonstrated more verbal imitation on the Uzgiris-Hunt Assessment Scales than the controls, but there were no statistically significant differences between the groups on the Objects Permanence, Schemes, or Objects in Space subscales. The two groups did not differ on the majority of demographic and environmental variables examined, suggesting that group differences may be due to differences in biomedical variables. However, within the myelomeningocele group, environmental variables correlated with the majority of the cognitive measures, while correlations between cognitive performance and both demographic and biomedical variables were at chance level.

Apgar Score↗
PubMed1995

Person and environment in HIV risk behavior change between adolescence and young adulthood.

This article explores how personal and environmental variables influence change in human immunodeficiency virus (HIV)-related risk behaviors between adolescence and young adulthood. Repeated interviews with 602 youths from 10 cities across the United States provide the data. These interviews first occurred in 1984-1985 and 1985-1986 when the youths were adolescents and were repeated again in 1989-1990 and 1991-1992 when they were all young adults. A longitudinal multivariate analysis shows that 31% of the variance in HIV risk behaviors by inner-city young adults is predicted by a combination of adolescent risk behaviors, personal variables (suicidality, substance misuse, antisocial behavior), environmental variables (history of child abuse, poor relations with parents, stressful events, peer misbehavior, number of AIDS prevention messages), and interactions between variables (number of neighborhood murders with child abuse, number of neighborhood murders with substance misuse, and unemployment rates with antisocial behavior).

Adolescent↗
PubMed1986

Temporal and microgeographic variation in allozyme frequencies in a natural population of Drosophila buzzatii.

Temporal variation in allozyme frequencies at six loci was studied by making monthly collections over 4 yr in one population of the cactophilic species Drosophila buzzatii. Ten sites were defined within the study locality, and for all temporal samples, separate collections were made at each of these sites. Population structure over microgeographic space and changes in population structure over time were analyzed using F-statistic estimators, and multivariate analyses of allele and genotype frequencies with environmental variables were carried out. Allele frequencies showed significant variation over time, although there were no clear cyclical or seasonal patterns. A biplot analysis of allele frequencies over seasons within years and over years showed clear discrimination among years by alleles at four loci. During the 4 yr, three alleles showed directional changes which were associated with directional changes in environmental variables. Significant associations with one or more environmental variables were found for allele frequencies at every locus and for both expected and observed heterozygosities (except those for Est-1 and Est-2). Thus, variation in allele frequencies over time cannot be attributed solely to drift. Significant linkage disequilibria were detected among three loci (Est-2, Hex and Aldox), but there was no evidence for spatial or temporal patterns. The F-statistic analyses showed significant differentiation among months within years for all loci, but the statistic used (coancestry) was heterogeneous among loci. Estimates of F (inbreeding) for all loci were significantly different from zero, with the loci in four groups, Adh-1 (negative), Pgm(small positive), Est-2 and Hex (intermediate) and Est-1 and Aldox (high positive). The correlation of genes within individuals within populations (f) for each locus in each month by site sample differed among loci, as did the (f) for each locus in each month by site sample differed among loci, as did the patterns of change in f over time (seasons). Heterogeneity in the F-statistic estimates indicates that natural selection is directly or indirectly affecting allele and genotype frequencies at some loci. However, the F-statistic analyses showed essentially no microgeographic structure (i.e., among sites), although there was significant heterogeneity in allele frequencies among flies emerging from individual rots. Thus, microspatial heterogeneity probably is most important at the level of individual rots, and coupled with habitat selection, it could be a major factor promoting diversifying selection and the maintenance of polymorphism.(ABSTRACT TRUNCATED AT 400 WORDS)

Alleles↗