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PubMed1993

Genotype x environment interactions in postweaning performance to yearling in Angus, Brahman, and reciprocal-cross calves.

Data from 431 Angus, Brahman, and reciprocal-cross calves were used to evaluate performance from weaning to yearling in calves managed during the winter on dormant common bermudagrass or endophyte-infected tall fescue (backgrounding environments). Calves on bermudagrass were weaned at heavier weights (P < .01) but gained less postweaning (P < .01). Weights at 365 d, 365-d hip heights, and 365-d weight:height ratios were similar between calves on different backgrounding environments averaged over breed. There was evidence that heterosis for postweaning ADG was larger in calves managed on endophyte-infected tall fescue (P < .05), but heterosis estimates for 205-d weight, 365-d weight, 365-d hip height, and 365-d weight:height were similar between backgrounding environments. Maternal and direct effects did not significantly interact with backgrounding environment, but there was a trend for maternal effects of 205-d weight, 365-d weight, and 365-d weight:height to be larger on the common bermudagrass environment than on the tall fescue environment. There was also a trend for direct breed effects for postweaning ADG and 365-d hip height to be larger on the common bermudagrass environment. These data indicated that genetic effects may vary with production environment and that consideration should be given to environment when developing crossbreeding systems.

Animal Feed↗

PubMed1987

Water and feed intake, feed efficiency, and abdominal fat levels of dwarf and normal chickens selected under different water:feed ratio environments.

Early feed and water intake, feed efficiency, and abdominal fat weights were investigated in normal and dwarf genotypes previously selected for high 8-wk body weight under .4 and 1.6% dietary salt environments. Progeny from the selected lines were evaluated on a normal .4% salt diet in two experiments following Generations 3 and 4. Progeny of lines selected on the .4% salt environment tended to have higher body weights and feed intake than progeny of lines selected on the 1.6% salt environment. There was evidence that progeny from normal birds previously selected on the 1.6% salt environment had higher initial (0 to 6 days) water:feed ratios than progeny of normal birds previously selected on the .4% salt environment, with ratios approximately 20% greater from 0 to 2 days in Generation 4 progeny. Feed efficiencies were similar within genotype across selection environments. However, feed efficiency of dwarfs appeared to be superior to feed efficiency of normals from 0 to 8 days, whereas at later ages, normals were more efficient. Normal females of lines selected in the 1.6% salt environment had from 13 to 29% less abdominal fat percentages than contemporaries from lines selected on the .4% salt environment at 63 to 66 days of age. Abdominal fat weights of dwarfs, however, were not influenced by the selection environment.

Adipose Tissue↗

PubMedDate not supplied

Workers' perceptions about worksite policies and environments and their association with leisure-time physical activity.

PURPOSE: To estimate the employed population's exposure to perceived worksite policies and environments hypothesized to promote physical activity and to determine their relationship to leisure-time physical activity. DESIGN: Cross-sectional, random-digit-dial telephone survey. SETTING: Community. SUBJECTS: Employed adults (n = 987) in six North Carolina counties. MEASURES: Outcomes included any leisure-time physical activity, recommended physical activity, and work-break physical activity. Perceived worksite policies and environments included on-site fitness facility at work, safe place to walk outside work, paid time for activity, subsidized health-club membership, and flexible work schedule. ANALYSIS: Descriptive statistics were used to describe the study population and exposure to perceived worksite policies and environments. Multivariable logistic regression was used to evaluate relationships between perceived worksite policies and environments and physical activity, controlling for age, race, sex, educational status, disability, and general health status. RESULTS: Various supportive worksite policies and environments were reported by 15% to 56% of employed participants. Associations between perceived worksite policies and environments and physical activity were strongest for having paid time for non-work-related physical activity, an on-site fitness facility at work, and subsidies for health clubs. Recommended activity was not associated with perceived worksite policies and environments. CONCLUSION: Worksite policies and environments are promising factors for future study in physical activity promotion. Studies should evaluate these relationships in other populations and explore measurement error in self-reported worksite policies and environments.

Adolescent↗

PubMed1999

[Family environment in eating disorders: a study of the familiar factors influencing the onset and course of eating disorders].

OBJECTIVE: This study investigated the association of family environment and symptomatic characteristics in eating disorders. METHOD: The subjects studied were 180 eating disorder patients who sought treatment at Tokai University Hospital and whose diagnoses were made using the SCID (Structured Clinical Interview for DSM-III-R) modified for DSM-IV. The subjects consisted of 52 Anorexia Nervosa Restricting Type (AN/R), 40 Anorexia Nervosa Binge-Eating/Purging Type (AN/BP), 57 Bulimia Nervosa Purging Type (BN/P), 17 Bulimia Nervosa Nonpurging Type (BN/NP) and 14 Binge-Eating Disorder (BED). All subjects were given the Family Adaptability & Cohesion Evaluation Scales III (FACES-III). Seventy eight female college students were administered the FACES-III, as normal controls. RESULTS: On the cohesion (CO) dimensions of FACES-III, most AN/R perceived their families as significantly enmeshed (high CO), whereas most BN and BED perceived their families as disengaged (low CO). The families of AN/BP rated lower CO than AN/R, and higher CO than BN. On the adaptability dimension of FACES-III, most AN/BP and BED perceived their families as rigid, and most BN/P perceived their families either rigid or chaotic. DISCUSSION: 1) The family environment of eating disorder patients exist, on a continuum of cohesion, from AN/R (enmeshed), through AN/BP (intermediate cohesion) and BN (disengaged), to BED (most disengaged). It's suggested that there might be an association of enmeshed family environment and severity of restrict-eating. In addition, the disengaged family environment might have an association with the onset of binge-eating. 2) It's also suggested that the two extremes on the adaptability dimension, rigid and chaotic, were the characteristic features of the family environment, which might precipitate and maintain binge-eating and purging symptoms. 3) The two hypotheses were proposed with regard to the familiar contribution on the outcome of AN/R. (a) AN/R, whose family environment are enmeshed, would not develop bulimic symptoms in the future. (b) AN/R, whose family environment are disengaged, particularly with rigid or chaotic atmosphere, have high risks of developing bulimia later. 4) The author discussed that dividing AN/BP into the two categories: binge subtype and non-binge subtype, should be recommended in the future diagnostic classification of the eating disorders, on the basis of analyzing both groups' family environments. 5) Comparing the family environment of the Japanese BED and the western BED suggested that the Japanese BED might be more severe in psychopathology. The author discussed the comorbidity of BED and the Borderline Personality Disorder, as well as the social influence on the clinical features of BED.

Adult↗

PubMed2000

[Comparison of the effectiveness and cost of treatment with humid environment as compared to traditional cure. Clinical trial on primary care patients with venous leg ulcers and pressure ulcers].

INTRODUCTION: The discovery of moist environment dressings as alternatives to the traditional treatments based on exposing wounds to air, opened new expectations for the care and treatment of chronic wounds. Over the years, these expectations have led to the availability of new moist environment dressings which have made it possible to improve the care provided to patients suffering this kind of wounds, as well as providing important reasons to weigh in terms of cost-benefit-effectiveness at the time of selecting which type of treatment should be employed. The lack of comparative analysis among traditional treatments and moist environment treatments for chronic wounds among patients receiving primary health care led the authors to perform an analysis comparing these aforementioned options of treatment on patients suffering venous leg ulcers or pressure ulcers. PATIENTS, MATERIALS AND METHODS: The authors designed a Randomized Clinical Trial involving patients receiving ambulatory care in order to compare the effectiveness and cost-benefit of traditional versus moist environment dressing during the treatment of patients suffering stage II or III pressure ulcers or venous leg ulcers. In this trial, variables related to effectiveness of both treatments, as well as their costs were analyzed. MAIN RESULTS: 70 wounds were included in this Randomized Clinical Trial, 41 were venous leg ulcers of which 21 received a moist environment treatment while 20 received traditional cure, the other 29 wounds were pressure ulcers of which 15 received moist environment dressings treatment and 14 received traditional dressings. No statistically significant differences were found among the defining variables for these lesions in either group under treatment. In the venous leg ulcer study group, the authors conclusions were an average of 18.13 days, 16.33 treatment sessions and a cost of 10,616 pesetas to heal one square centimeter of the initial surface area of a wound on patients treated with traditional treatment compared to an average of 18.22 days, 4.54 treatment sessions and a cost of 2409 pesetas to heal one square centimeter of the initial surface area of a wound on patients treated with moist environment dressings. In the pressure ulcers study group, the authors conclusions were an average of 12.18 days, 12.1 treatment sessions and a cost of 15,490 pesetas to heal one square centimeter of the initial surface area of a wound on patients treated with traditional treatment compared to an average of 7.12 days, 1.86 treatment sessions and a cost of 2610 pesetas to heal one square centimeter of the initial surface area of a wound on patients treated with moist environment dressings. COMMENTS: The results of this randomized clinical trial demosntrated that the moist environment treatment group was more effective and had a better cost-benefit ratio than the traditional treatment group in the treatment of pressure ulcers and venous leg ulcers on patients cared for by nursing personnel in primary health care centers all of which agrees with publications consulted by authors.

Chronic Disease↗

PubMed1990

Ecology of mesophilic Aeromonas spp. in aquatic environments of a temperate region and relationship with some biotic and abiotic environmental parameters.

The Ecology of mesophilic Aeromonas species has been investigated since January 1988 to examine their occurrence and distribution in aquatic environments of Okayama Prefecture. Water and plankton samples were quantitatively as well as qualitatively analyzed throughout the seasons from five selected stations including fresh, brackish, and saline environments. Analysis of variance and correlation coefficients among the biotic and abiotic parameters were sought. The organisms were found in all the environs with high densities through all the seasons. Plankton samples yielded higher counts of Aeromonas than the water samples in all the environs. Water temperature seemed to play a significant role on their growth during the winter months, however, no significant seasonal variation nor any correlation with fecal pollution were observed in most of the environments. A reciprocal relationship was seen with salt concentration in the saline environment. Among the currently recognized mesophilic species; A. caviae, A. hydrophila, A. sobria, and A. media were isolated with the predominance of anaerobic biovar. The present study reveals that Aeromonas are widely distributed in fresh, brackish and saline environments of this region. The study also reveals that Aeromonas are autochthonous members in aquatic ecosystems and are indigenous to these environs. Aeromonas species isolated from our environments were found to exhibit drug resistance potential which differed from that of isolates from diverse geographical locales. The high incidence of clinically significant Aeromonas species in this aquatic region could be of public health significance for the inhabitants of this region, as well as a challenge to their dependence on aquatic resources.

Aeromonas↗

PubMed1996

[Analytic methods for seed models with genotype x environment interactions].

Genetic models with genotype effect (G) and genotype x environment interaction effect (GE) are proposed for analyzing generation means of seed quantitative traits in crops. The total genetic effect (G) is partitioned into seed direct genetic effect (G0), cytoplasm genetic of effect (C), and maternal plant genetic effect (Gm). Seed direct genetic effect (G0) can be further partitioned into direct additive (A) and direct dominance (D) genetic components. Maternal genetic effect (Gm) can also be partitioned into maternal additive (Am) and maternal dominance (Dm) genetic components. The total genotype x environment interaction effect (GE) can also be partitioned into direct genetic by environment interaction effect (G0E), cytoplasm genetic by environment interaction effect (CE), and maternal genetic by environment interaction effect (GmE). G0E can be partitioned into direct additive by environment interaction (AE) and direct dominance by environment interaction (DE) genetic components. GmE can also be partitioned into maternal additive by environment interaction (AmE) and maternal dominance by environment interaction (DmE) genetic components. Partitions of genetic components are listed for parent, F1, F2 and backcrosses. A set of parents, their reciprocal F1 and F2 seeds is applicable for efficient analysis of seed quantitative traits. MINQUE(0/1) method can be used for estimating variance and covariance components. Unbiased estimation for covariance components between two traits can also be obtained by the MINQUE(0/1) method. Random genetic effects in seed models are predictable by the Adjusted Unbiased Prediction (AUP) approach with MINQUE(0/1) method. The jackknife procedure is suggested for estimation of sampling variances of estimated variance and covariance components and of predicted genetic effects, which can be further used in a t-test for parameter. Unbiasedness and efficiency for estimating variance components and predicting genetic effects are tested by Monte Carlo simulations.

Genotype↗

PubMed2004

Changing the environment to promote health-enhancing physical activity.

Supportive environments have been used to change and influence health behaviours like smoking. While psychological and ecological theories and models demonstrate the possible influences of the environment on health-enhancing physical activity (HEPA), little is known about the effectiveness of the environmental interventions. This paper presents the results of a systematic review of studies that used environmental interventions to increase health-enhancing physical activity. Two groups of studies were found, studies that changed the physical environment by creating new HEPA facilities, policies and supporting mechanisms, and studies that used the elements of the environment as an active or sedentary 'point of choice', via educational materials to promote stair use. Environmental change studies showed a small increase on HEPA behaviour, but the relative impact of environment changes was not evaluated. A number of before and after studies have observed a weak effect of a simple environmental change to stimulate stair climbing while travelling or shopping. Current national policy has embraced the environment as an option for promoting health-enhancing physical activity, especially active travel, in spite of the lack of effectiveness data. It is recommended that existing or planned public health environment and HEPA initiatives should use appropriate evaluation methods to assess their efficacy and effectiveness. Further developmental research into the nature of the relationship of the environment to particular HEPA behaviours is strongly recommended before developing new environmental interventions.

Environment Design↗

PubMed2005

Relationships among growth, development and plastic response to environment quality in a perennial plant.

Phenotypic traits differ between plants in different environments and within individuals as they grow and develop. Comparing plants in different environments at a common age can obscure the developmental basis for differences in phenotype means in different environments. Here, we compared trait means and patterns of trait ontogeny for perennial (Viola septemloba) plants growing in environments that differed in quality either naturally or due to experimental manipulation. Consistent with predictions for adaptive stress resistance, plants grown in lower-quality environments allocated proportionately more biomass to roots and rhizomes, and produced smaller, thicker and longer-lived leaves. The developmental trajectory of almost all traits differed between environments, and these differences contributed to observed differences in trait means. Plants were able to alter their initial developmental trajectory in response to an increase in resources after 8 wk of growth. This result contrasts with previous findings, and may reflect a difference in the way that annual and perennial species respond to stress. Our results demonstrate the complexity of interactions between the environment and the development of the phenotype that underlie putatively adaptive plastic responses to environment quality.

Adaptation, Physiological↗

PubMed2003

Associations between school environments and childhood traumatic dental injuries.

PURPOSE: To assess the associations between social and physical school environments and the prevalence of traumatic dental injuries (TDI) in 12-year-old children in Thailand. MATERIALS AND METHODS: A cross-sectional study in 52 urban schools in Thailand was carried out from a sample of 2,725 12-year-old children that were clinically examined for TDI and interviewed. Cluster analyses were performed to classify the schools into supportive and non-supportive schools by social and physical environmental characteristics. Analyses of the associations were performed using multilevel analyses, accounting for school variations and controlling for confounding factors at the child level. RESULTS: 35.0% of children had TDI. Prevalence was twice as high amongst boys than girls. The prevalence of TDI was significantly lower in the schools with a supportive social environment (Crude OR = 0.6 (95% CI = 0.4 to 0.8, p = 0.004)). The adjusted OR was 0.7 (95% CI = 0.5 to 0.9, p = 0.02). This statistically significant association existed in boys but there was only an insignificant tendency of association in girls. There was no statistically significant association between TDI and the physical environment of the schools. But there was an insignificant tendency of association with the physical environment in girls. CONCLUSION: TDI were much more common in boys than girls. TDI were significantly less prevalent in male children in schools with supportive, compared to less supportive social environments. In boys, there was a tendency for the more socially supportive environment to be more protective rather than the effect of any type of physical environment. In girls, this protective tendency was only apparent when school environments were both more socially supportive, and physically favourable.

Child↗

PubMed1996

Women's work environment and health: clerical workers in Brazil.

Although women are participating more in the formal workforce, the majority are employed primarily in low-income and low-status occupations. While work roles may provide women with some rewards, employment may also create many stressful demands on their daily lives. As part of an international study, 60 female Brazilian clerical workers responded to a self-administered questionnaire describing what they liked, disliked, and found stressful about the structural, physical, and social aspects of their work environment. Participants also identified strategies they used to cope with stress in the work environment. Dimensions of healthy environments identified in the data included utility, challenge, participation, safety, pleasing workplace, valuation, clarity of roles, and empowerment. Unhealthy environments were characterized by hazards, bureaucracy, devaluation, and economic constraints. Participants described their concerns about the effect of the environment on their physical and mental health, but tended to adopt a passive, resigned coping style rather than a proactive approach to co-creating a healthier work environment. The results and their relationship to healthy work environments are discussed within the context of the larger sociopolitical environment of Brazil.

Adaptation, Psychological↗

PubMed2001

A trade-off in task allocation between sensitivity to the environment and response time.

Task allocation is the process that adjusts the number of workers in each colony task in response to the environment. There is no central coordination of task allocation; instead workers use local cues from the environment and from other workers to decide which task to perform. We examine two aspects of task allocation: the sensitivity to the environment of task distribution, and the rate of response to environmental changes. We investigate how these two aspects are influenced by: (1) colony size, and (2) behavioral rules used by workers, i.e. how a worker uses cues from the environment and from social interactions with other workers in deciding which task to perform. We show that if workers use social cues in their choice of task, response time decreases with increasing colony size. Sensitivity of task distribution to the environment may decrease or not with colony size, depending on the behavioral rules used by workers. This produces a trade-off in task allocation: short response times can be achieved by increasing colony size, but at the cost of decreased sensitivity to the environment. We show that when a worker's response to social interactions depends on the local environment, sensitivity of task distribution to the environment is not affected by colony size and the trade-off is avoided.

Animals↗

PubMedDate not supplied

The theory of the organism-environment system: I. Description of the theory.

The theory of the organism-environment system starts with the proposition that in any functional sense organism and environment are inseparable and form only one unitary system. The organism cannot exist without the environment, and the environment has descriptive properties only if it is connected to the organism. Although for practical purposes we do separate organism and environment, this common-sense starting point leads in psychological theory to problems which cannot be solved. Therefore, separation of organism and environment cannot be the basis of any scientific explanation of human behavior. The theory leads to a reinterpretation of basic problems in many fields of inquiry and makes possible the definition of mental phenomena without their reduction either to neural or biological activity or to separate mental functions. According to the theory, mental activity is activity of the whole organism-environment system, and the traditional psychological concepts describe only different aspects of organization of this system. Therefore, mental activity cannot be separated from the nervous system, but the nervous system is only one part of the organism-environment system. This problem will be dealt with in detail in the second part of the article.

Animals↗

PubMedDate not supplied

The theory of the organism-environment system: III. Role of efferent influences on receptors in the formation of knowledge.

UNLABELLED: The present article is an attempt to give-in the frame of the theory of the organism-environment system (Jarvilehto, 1998a)-a new interpretation to the role of efferent influences on receptor activity and to the functions of senses in the formation of knowledge. It is argued, on the basis of experimental evidence and theoretical considerations, that the senses are not transmitters of environmental information, but create a direct connection between the organism and the environment, which makes the development of a dynamic living system, the organism-environment system, possible. In this connection process, the efferent influences on receptor activity are of particular significance because, with their help, the receptors may be adjusted in relation to the parts of the environment that are most important in achieving behavioral results. Perception is the process of joining of new parts of the environment to the organism-environment system; thus, the formation of knowledge by perception is based on reorganization (widening and differentiation) of the organism-environment system, and not on transmission of information from the environment. With the help of the efferent influences on receptors, each organism creates its own peculiar world that is simultaneously subjective and objective. The present considerations have far-reaching influences as well on experimental work in neurophysiology and psychology of perception as on philosophical considerations of knowledge formation. KEYWORDS: efferent, epistemology, influences, knowledge, movement, perception, receptors, senses, systems approach.

Animals↗

PubMed1998

Constructing a home birth environment through assuming control.

OBJECTIVE: The purpose of this qualitative study was to describe the experience of couples who have had a home birth. DESIGN, SETTING AND PARTICIPANTS: A phenomenological approach was used to provide an understanding of the human experience of home birth in Western Australia. The research design consisted of a field study, in which 10 parent couples were interviewed and three videos of home births observed. Of the ten couples, four couples spoke of their first baby's home birth and the remaining six couples had three or four children who had been born at home. FINDINGS: The couples' experiences of home birth were gained through identifying significant statements from transcripts and field notes, and clustering these into the following four themes: 'constructing the environment'; 'assuming control'; 'birthing'; and 'resolving expectations'. The themes of 'constructing the environment' and 'assuming control' are described in detail in this paper. 'Constructing the environment' describes how couples adapted the physical environment, and established support to create a positive birth environment. 'Assuming control' discusses exerting control and taking responsibility for the birth. The remaining themes of 'birthing' and 'resolving expectations' are described in a subsequent paper (Morison et al, in press). KEY CONCLUSIONS: The research furnishes an insight into the couples' experience of home birth. The lived experience of birthing at home involved a process where a couple actively created an environment that enabled them to assume control and responsibility for the birth. IMPLICATIONS FOR PRACTICE: The findings are important for midwives in any setting, as they reveal the extent to which some parents value the right to assume control and responsibility for the birth of their baby. Although the physical environment of a home birth cannot be replicated in every setting, issues specific to the birth environment are relevant to all midwives.

Adult↗

PubMed1997

Integrating nature and nurture: implications of person-environment correlations and interactions for developmental psychopathology.

The developmental interplay between nature and nurture is discussed, with particular reference to implications for research in developmental psychopathology. The general principles include individual differences in reactivity to the environment, two-way interplay between intraindividual biology and environmental influences, and the need to consider broader social contextual features. Individuals actively process their experiences; they also act on their environment to shape and select their experiences, and individual characteristics change over time. Key findings on genetic effects include their ubiquitous influence, the multifactorial origin of most psychopathology, the involvement of several genes in most mental disorders, some genetic effects operate through dimensional risk features rather than directly on disorder, some genetic effects are dependent on gene-environment correlations and interactions, and genetic effects increase with age. Key findings on environmental effects include their ubiquitous influence, the genetic mediation of some supposed environmental effects, the importance of passive gene-environment correlations, the paucity of evidence regarding environmental effects on lifetime liability to psychopathology, the lack of understanding of environmental effects on the organism, and the importance of nonshared environmental effects. Research strategies to investigate environmental risk mediation include the range of genetically sensitive designs, migration studies, secular trend investigations, studies of nonfamilial environments, and examination of intraindividual change in relation to measured environmental alterations. Proximal processes involved in person-environment interplay are discussed in relation to person-environment interactions and evocative and active person-environment correlations.

Adaptation, Psychological↗

PubMed1997

Multivariate life testing in variably scaled environments.

This paper examines modeling and inference questions for experiments in which different subsets of a set of kappa possibly dependent components are tested in r different environments. In each environment, the failure times of the set of components on test is assumed to be governed by a particular type of multivariate exponential (MVE) distribution. For any given component tested in several environments, it is assumed that its marginal failure rate varies from one environment to another via a change of scale between the environments, resulting in a joint MVE model which links in a natural way the applicable MVE distributions describing component behavior in each fixed environment. This study thus extends the work of Proschan and Sullo (1976) to multiple environments and the work of Kvam and Samaniego (1993) to dependent data. The problem of estimating model parameters via the method of maximum likelihood is examined in detail. First, necessary and sufficient conditions for the identifiability of model parameters are established. We then treat the derivation of the MLE via a numerically-augmented application of the EM algorithm. The feasibility of the estimation method is demonstrated in an example in which the likelihood ratio test of the hypothesis of equal component failure rates within any given environment is carried out.

Algorithms↗

PubMed2003

Human navigation in nested environments.

Navigation in humans and many other animals relies on spatial representations of their environments. Three experiments examined how humans maintain sense of orientation between nested environments. Subjects can acquire new spatial representations easily without integrating them into their existing spatial knowledge system. While navigating between nested environments, subjects seemed to constantly switch between the currently processed environment by reorienting to approaching environments and losing track of old environments at given spatial regions. These results suggest that spatial updating in naturalistic, nested environments does not occur for all environments at the same time. Implications for the hierarchical theory of spatial representations and the path integration theory of navigation are discussed.

Environment↗