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At least 1,153 records · Page 64Linked to original sources
PubMed1996

Providing controlled environments for plant growth in space.

Providing a controlled environment for growth of plants in a space environment involves development of unique technologies for the various subsystems of the plant growing facility. These subsystems must be capable of providing the desired environmental control within the operational constraints of currently available space vehicles, primarily the US Space Shuttle or the Russian Space Station, MIR. These constraints include available electrical power, limited total payload mass, and limited volume of the payload. In addition, the space hardware must meet safety requirements for a man-rated space vehicle. The ASTROCULTURE (TM) space-based plant growth unit provides control of temperature, humidity, and carbon dioxide concentration of the plant chamber air. A light emitting diode (LED) unit provides red and blue photons with a total intensity adjustable from 0 to 500 micromoles m-2 s-1. Ethylene released by the plant material is removed with a non-consumable ethylene removable unit. A porous tube and rooting matrix subsystem is used to supply water and nutrients to the plants. The ASTROCULTURE(TM) flight unit is sized to be accommodated in a single middeck locker of the US Space Shuttle, the SPACEHAB module, and with slight modification in the SPACELAB module. The environmental control capabilities of the subsystems used in the ASTROCULTURE(TM) flight unit have been validated in a microgravity environment during five US Space Shuttle missions, including two with plants. The unique environmental control technologies developed for the space-based plant growth facility can be used to enhance the environmental control capabilities of terrestrial controlled environment plant chambers.

Agriculture↗
PubMed2006

Community assembly in experimental grasslands: suitable environment or timely arrival?

It is hard to defend the view that biotic communities represent a simple and predictable response to the abiotic environment. Biota and the abiotic environment interact, and the environment of an individual certainly includes its neighbors and visitors in the community. The complexity of community assembly calls forth a quest for general principles, yet current results and theories on assembly rules differ widely. Using a grassland microcosm as a model system, we manipulated fertility, disturbance by defoliation, soil/microclimate, and arrival order of species belonging to two groups differing in functional attributes. We analyzed the outcome of community assembly dynamics in terms of species richness, invasibility, and species composition. The analyses revealed strong environmental control over species richness and invasibility. Species composition was mainly determined by the arrival order of species, indicating that historical contingency may change the outcome of community assembly. The probability for multiple equilibria appeared to increase with productivity and environmental stability. The importance of arrival order offers an explanation of the difficulties in predicting local occurrences of species in the field. In our experiment, variation in fertility and disturbance was controlling colonization with predictable effects on emergent community properties such as species richness. The key mechanism is suggested to be asymmetric competition, and our results show that this mechanism is relatively insensitive to the species through which it works. While our analyses indicate a positive and significant correlation between richness and invasibility, the significance disappears after accounting for the effect of the environment. The importance of arrival order (historical contingency) and environmental control supports the assumption of the unified neutral theory that different species within a trophic level can be considered functionally equivalent when it comes to community assembly. However, our results indicate that variation in asymmetric competition is the key factor determining the richness of the resulting communities, and this is far from neutral.

Biodiversity↗
PubMed2003

The built environment and its relationship to the public's health: the legal framework.

The built environment significantly affects the public's health. This was most obvious when infectious disease was the primary public health threat during the industrial revolution; unsanitary conditions and overcrowded urban areas facilitated the spread of infection. However, even today in the age of chronic diseases there remains an important connection between population health and the built environment. Physical spaces can expose people to toxins or pollutants and influence lifestyles that contribute to diabetes, coronary vascular disease, and asthma. Public health advocates can help shape the design of cities and suburbs in ways that improve public health, but to do so effectively they need to understand the legal framework. This article reviews the connection between public health and the built environment and then describes the legal pathways for improving the design of our built environment.

Building Codes↗
PubMed2003

Creating healthy communities, healthy homes, healthy people: initiating a research agenda on the built environment and public health.

Mounting evidence suggests physical and mental health problems relate to the built environment, including human-modified places such as homes, schools, workplaces, parks, industrial areas, farms, roads and highways. The public health relevance of the built environment requires examination. Preliminary research demonstrates the health benefits of sustainable communities. However, the impact of mediating and moderating factors within the built environment on health must be explored further. Given the complexity of the built environment, understanding its influence on human health requires a community-based, multilevel, interdisciplinary research approach. The authors offer recommendations, based upon a recent conference sponsored by the National Institute of Environmental Health Sciences (NIEHS), for research and policy approaches, and suggest interagency research alliances for greater public health impact.

City Planning↗
PubMed2005

Artificial environments and an aging population: designing for age-related functional losses.

Over the past century there has been a large and continuing increase in the frequency of persons aged over 65 years; particularly those aged over 100 years. During the 21st century the number of persons over 100 years will continue to increase. This will occur at such a rapid rate that the 21st century may one day be called the century of centenarians. Frailty and disability secondary to senescence, disease, and trauma have accompanied old age (often defined as age 65 and over) as far back as recorded history. However, during the 20th century, age, frailty, disability, and chronic degenerative diseases have been decoupled to some extant in the most long-lived human populations. Until recently, there was little need to design artificial environments for the unique needs of the elderly due to their low representation in most national populations. Today that need is increasing in concert with the number of persons aged 65 and older. The purpose of this review is to suggest areas wherein physiological anthropologists may have an opportunity to contribute to design trends for this rapidly increasing aging population. Major considerations for design of environments for the elderly are based upon altering the environment to accommodate their declining visual, auditory, and kinesthetic senses, thereby enhancing their declining faculties and improving their autonomy, independence, and self perceptions of well-being. To date most design considerations have been directed toward improving environments for those suffering from Alzheimer's disease or residing within assisted living facilities. Many such design improvements also may be effective in improving life satisfaction and functional abilities of the non-institutionalized elderly.

Activities of Daily Living↗
PubMed2005

The physiological homeostasis of human populations in variable environments.

A close evolutionary relationship of physiology and ecology of organisms determines the dynamic dependence of the population physiological status in man on ecological factors. For the explanation of the stability and variability of population physiological status the concept of physiological homeostasis was applied. The investigation of physiological status in several populations of Middle Asia, Kazakhstan, North-East Asia and Khakassia has shown that reversible changes in the environment may temporarily destabilize the equilibrium in the "population-environment" system and prolonged stresses may cause a state of disadaptation. For estimation of population physiological homeostasis dependent on the environment, generalized dispersion, correlation and factor analyses are very informative. They not only mark the violation of population homeostasis, but also indicate changes in the environment.

Adaptation, Physiological↗
PubMed2005

Proposal for a framework for optimizing artificial environments based on physiological feedback.

We propose and then evaluate a new framework for finding the physical parameters of an artificial environment which give rise to given target physiological characteristics. We assume that a human is a system that takes as inputs the physical parameters of an artificial environment and outputs physiological parameters in response. We define our task as the inverse problem; we must find the best inputs from given target outputs. Our proposed framework solves the inverse problem using evolutionary computation techniques to optimize an artificial environment. We evaluate this framework using a simulation with a vibration environment and verify that it works.

Environment, Controlled↗
PubMed2005

The difference among generations in evaluating interior lighting environment.

This paper explores the difference among generations in evaluating interior lighting environment, and provides some knowledge for interior lighting design, which can accommodate all generations. Fifteen Computer Graphic pictures, which had the same dimensions (W3000 mmxH2800 mmxD6300 mm) but a different luminous environment are evaluated. Pictures are presented on a screen with a liquid crystal projector in a shaded dark room.A Semantic Differential technique with 12 subjective scales with 5 steps was used for the evaluation. Participants were chosen from 3 age groups: young, middle age, and elderly people.A difference among generations in evaluating interior lighting environment emerged. These tendencies could not be explained solely by visibility. It seems that the personal experience is closely related to the evaluation and preference of luminous environment.

Adult↗
PubMed1988

Social environment and regimen adherence among type II diabetic patients.

We investigated the reliability and predictive validity of several measures of the social environment using a sample of 127 adults with type II (non-insulin-dependent) diabetes. Of particular interest was a revised scale of family support for performing diabetes self-care behaviors. Across four different aspects of the diabetes regimen, it was consistently found that regimen-specific measures of family support differentiated subjects who were low, medium, or high on adherence better than global family-support scores. Social-environment measures were generally successful in predicting a subject's level of regimen adherence after accounting for variance attributable to demographic factors. The family-support measures were the strongest and most consistent predictors of adherence, but measures of stress and medical-care satisfaction and the interaction between stress and the other social-environment measures also often improved the prediction of a subject's adherence status. These results support the usefulness of measures of the social environment specific to diabetes, and research to investigate other aspects of the social context of regimen adherence is recommended.

Adult↗
PubMed1982

Infants' mental and motor development: effects of home environment, maternal attitudes, marital adjustment, and socioeconomic status.

27 two-yr.-old infants and their mothers were studied in their homes to analyze the relationship between infants' development and their home environment, mothers' attitudes as parents, mothers' marital adjustment, and families' socioeconomic status. Bayley Mental Development Indexes correlated with the infants' home environment, families' socioeconomic status, and maternal attitudes. Bayley Psychomotor Development Indexes related to home environment and socioeconomic status. Home environment, maternal attitude, and marital adjustment scores correlated with socioeconomic status. The implications of these ecological factors on infants' mental and motor development are discussed.

Attitude↗
PubMed2002

Confirmatory factor analysis of the group environment questionnaire with co-acting sports.

To assess whether the Group Environment Questionnaire is applicable to athletes in co-acting sports such as track and field, the factor structure of the Group Environment Questionnaire among a heterogeneous sample of 199 co-acting team sport athletes was investigated. A confirmatory factor analysis did not support the hypothesized four-factor model. A subsequent exploratory factor analysis yielded two independent factors that had no interpretable pattern of the four Group Environment Questionnaire factors within them. While this finding requires replication and confirmation, the four-factor model of the Group Environment Questionnaire does not appear to be as valid for co-acting sports as for interacting sports.

Adolescent↗
PubMed1993

Brain, environment, heredity, and personality.

Behavior genetics research, committed to a model of the origins of personality and intellectual development restricted to heredity and environment, consistently generates evidence for two types of environmental influences. One of these, termed the between-family or shared environment, creates no conceptual problems. The other, termed the nonshared or within-family or unique environment, does. The other, termed the nonshared or within-family or unique environment, does. The latter accounts for a substantial portion of the variance in personality and intellect, it must be unique to each individual, and its origin has not been determined. It is contended here that the brain itself, as an inherently indeterminate dynamic system, is the source of this unresolved developmental variability.

Animals↗
PubMed2001

Genotype x environment interactions in milk yield and quality in Angus, Brahman, and reciprocal-cross cows on different forage systems.

Milk yield and quality were observed on 93 Angus, Brahman, and reciprocal-cross cows over 3 yr to evaluate the interactions of direct and maternal breed effects and heterosis with forage environment. Forage environments were common bermudagrass (BG), endophyte-infected tall fescue (E+), and a rotational system (ROT) of both forages, in which each forage (BG or E+) was grazed during its appropriate season, usually June through October for BG and November through May for E+. Milk yield was estimated each of 6 mo (April through September) via milking machine and converted to a 24-h basis. Milk fat, milk protein, and somatic cell count were analyzed by a commercial laboratory. Heterosis for milk yield was similar among forages, averaging 2.4 kg (P < 0.01). Expressed as percentages of purebred means, heterosis for milk yield was largest on E+ (52.8%), intermediate on ROT (39.3%), and smallest on BG (23.7%). Direct breed effects for milk yield favored Brahman, and they were similar among forages but tended to be larger for E+ (2.5 kg) and ROT (2.8 kg) than for BG (1.3 kg). Direct breed effects for milk fat favored Brahman and were similar among forages but tended to be larger for E+ (1.0%) and ROT (1.0%) than for BG (0.6%). Purebred cows exceeded crossbreds in milk protein by 0.1% on ROT (P < 0.10). Crossbred cows had lower somatic cell counts than purebreds on BG (P < 0.05), E+ (P < 0.01), or ROT (P > 0.30). Heterosis for somatic cell counts as percentages of purebred means was similar for BG (-68.3%) and E+ (-68.9%) and less favorable for ROT (-31.6%). Maternal breed effects for somatic cell count favored Angus on ROT (P < 0.10) with a similar nonsignificant trend on BG and E+. Direct breed effects for somatic cell count favored Brahman on ROT (P < 0.10) with similar nonsignificant trends on BG and E+. These results suggested that a rotation of cows from E+ to BG in the summer can partially alleviate negative effects of E+ on milk yield. Conclusions also indicated an advantage to crossbred cows in somatic cell count and provided evidence of both direct and maternal breed effects for this trait. The results also suggested that direct breed effects for milk yield, milk fat, and somatic cell count and heterosis for milk yield and somatic cell count (as percentages of purebred means) tended to vary with forage environment, indicating a potential for genotype x environment interaction for these traits.

Animal Feed↗
PubMed2005

Genotype x environment interaction effects on carcass traits in Japanese Black cattle.

The importance of genotype x environment (region or management system) interactions for carcass traits in Japanese Black cattle was investigated using both univariate and multivariate animal models. The univariate approach was used mainly to test the significance of interaction effects. The multivariate approach was used to estimate genetic correlations, which indicated the magnitude of genotype x environment (GE) interactions. The more a genetic correlation deviates from 1, the larger the interaction. From the univariate approach, the addition of genotype x environment (region or management system) interaction (co)variance components resulted in an improved fit of the model for all traits in both cases (P < 0.001). However, estimates of genetic correlation between regions obtained from the multivariate approach for hot carcass weight, LM area, rib thickness, s.c. fat thickness, and marbling score were 0.97, 0.95, 0.93, 0.97, and 0.93, respectively. The corresponding estimates between management systems were 0.84, 0.92, 0.84, 0.90, and 0.97, respectively. These results indicate that GE interaction effects on carcass traits of Japanese Black cattle may be biologically unimportant. Therefore, breeding values obtained using the multivariate method would rank sires similarly in all environments. Consequently, carcass traits measured in these two different regions or management systems can be treated as the same traits.

Animal Husbandry↗
PubMed1985

Selection for weaning weight in Targhee sheep in two environments. II. Correlated effects.

Targhee sheep were selected for 120-d weight under irrigated pasture-drylot conditions at Davis (DW) and under range conditions at Hopland (HW). Unselected control lines were maintained in both environments (DC, HC1 and HC2). At Hopland, a line (DH) was maintained in which ewes were mated to Davis (DW) rams. Selection for 120-d weight was successful in both environments, with more improvement made in the drylot environment. The genetic improvement made in the drylot environment was expressed, although to a lesser degree, under range conditions. Correlated responses were analyzed. Birth weight increased significantly in all three selected lines; the increase was less in line DH than in the other two lines. In all selected lines, weights of ewes of all ages at mating increased significantly compared with their respective controls. Proportion of ewes lambing decreased (P less than .05) in line DH; the trend was negative but nonsignificant in line DW. Differences in litter size between lines within location were not significant. Lamb survival to weaning decreased in lines DW (P less than .05) and DH (P less than .01), compared with their respective controls; and the trend in HW was negative but nonsignificant. Fertility and survival data indicated that, under range conditions, the line selected under drylot conditions (DH) was less fit than the line selected under range conditions (HW). As a result of the decreases in lamb survival and fertility, none of the selected lines produced more total lamb weight weaned per ewe than the controls, in spite of the significant direct response to selection. Mature ewes of lines DH and DW produced less total lamb weight weaned per ewe (P less than .001 and P less than .05) than their respective controls. The results indicate that while single trait selection for growth rate to weaning results in heavier lambs, it does not increase and may decrease total lamb production per ewe.

Animals↗
PubMed1986

The influence of genetics and household environment upon the variability of normal blood pressure: the Montreal Adoption Survey.

The Montreal Adoption Survey was conducted as a cross-sectional epidemiologic study of cardiovascular risk factors in French Canadian families. Analysis included blood pressure readings of 756 adopted and 445 natural children as well as 1176 parents. A genetic model was applied to the analysis of our data. Interindividual variability of blood pressure was studied and observed correlatives of systolic and diastolic pressure of parental and non parental subjects were calculated. Based on the maximum likelihood estimates presented in the models the explanation of the parent offspring and the between sibs expected population correlatives for systolic blood pressure was the following: 61% was due to shared genes and 39% to environment shared by both parents and children. For diastolic blood pressure the explanation between parents and offspring was the following: 58% was due to shared genes and 42% due to shared environment across generation. The explanation between sibs was estimated to be the following: 33% due to generation, 24% to shared environment across generation and 43% to shared environment within generation.

Adoption↗
PubMed1998

The substance use system: social and neighborhood environments associated with substance use and misuse.

Substance use theory and practice have traditionally focused on individuals who misuse substances or who are at risk for substance misuse, but this emphasis is shifting. The present study views both substance use and misuse systematically, assessing the relationships between the physical and social environments and substance use and misuse in dynamic interplay. This substance use system was examined through a survey of approximately 10,000 persons, aged 22-44, from primarily inner-city neighborhoods in the United States. Individual indicators such as race, sex, age, socioeconomic status, education, and religious service attendance relate to both the physical and interpersonal environments, even when each is controlled for the others. Qualities of both environments are strongly associated with substance dependency, even after individual indicators are controlled. These findings suggest the difficulty of bringing about change in drug and alcohol use without fundamental change in the environments where use takes place.

Adult↗
PubMed2003

Identification of factors that cause genotype by environment interaction between herds of Holstein cattle in seventeen countries.

Currently, the International Bull Evaluation Service calculates international dairy sire evaluations using the multiple-trait across country evaluation procedure. This method depends implicitly on political boundaries between countries, because the input data are national evaluations from each participating country. Therefore, different countries are treated as different production environments. The goal of this study was to identify factors that describe the production system on each farm. Such factors could be used to group herds across countries for borderless genetic evaluations. First lactation milk records of Holstein cows calving between January 1, 1990 and December 31, 1997 in Australia, Austria, Belgium, Canada, Czech Republic, Estonia, Finland, Germany, Hungary, Ireland, Israel, Italy, The Netherlands, New Zealand, South Africa, Switzerland, and the USA were used in this study. Thirteen genetic, management, and climatic variables were considered as potential indicators of production environments: peak milk yield, persistency, herd size, age at first calving, seasonality of calving, standard deviation of milk yield, culling rate, days to peak yield, fat to protein ratio, sire PTA milk, percentage of North American Holstein genes, maximum monthly temperature, and annual rainfall. Herds were grouped into quintiles based on herd averages for each of these variables. Genetic correlations for lactation milk yield between quintiles were significantly less than one for maximum monthly temperature, sire PTA milk, percent North American Holstein genes, herd size, and peak milk yield. The variables can be used to group herds into similar production environments, regardless of country borders, for the purpose of accounting for genotype by environment interaction in international dairy sire evaluation.

Aging↗