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PubMed1991

Body fat in identical twins reared apart: roles for genes and environment.

We report analyses of data on body fat from a cohort of 34 separated monozygotic twin pairs (MZA) and a matched sample of 38 pairs of monozygotic twins reared together (MZT) originally studied by James Shields. The correlation for MZA pairs was .61 and the correlation for MZT pairs was .75. These correlations did not differ significantly, nor did correlations differ between MZA pairs subclassified as having been raised in relatively more or less similar environments. Our results suggest important roles for both genes and environment in the accumulation of body fat and support other adoption studies in suggesting that adult environments rather than rearing environments are the most important nongenetic determinants of levels of body fat in adults.

Adipose Tissue↗

PubMed1978

[Preventive measures in the management of the environment].

The natural and the man made environment influence the wellbeing and the health of the population. The management of the environments aims at the improvement of health and the disposal of health risks. The physical and psycho-social environment has to be taken into consideration, especially in connection with work, housing, energy consumption and spare time activities. Laws concerning environmental protection and energy supply could contribute to improvement of the environment.

Conservation of Natural Resources↗

PubMed1988

Child-environment relationships: a cross-cultural study of educable mentally retarded children and their families.

A cross-cultural study was conducted to determine the generality of child-environment relationships in Japanese and American families with educable mentally retarded (EMR) children. A total of 90 families with EMR children in Japan and 93 families with EMR children in America participated. The Henderson Environment Learning and Process Scale, Family Environment Scale, and Home Quality Rating Scale were employed in home interviews and observations. The AAMD Adaptive Behavior Scale was used to measure social competency and psychosocial adjustment of the children. The results indicated that the relation between cognitive opportunities at home and the child's social competency appeared similar between the two cultures. However, the relation between the affective aspects of home environment and the child's psychosocial adjustment appeared to differ between the two cultures.

Activities of Daily Living↗

PubMed1997

Skin derivative control of thermal environment in a closed incubator.

Defining a thermoneutral environment remains difficult because thermoneutrality depends on both physical and physiological factors. A servocontrolled skin temperature derivative (SCS) heating device has been designed to control the thermal environment in closed incubators without the necessity of setting an air or skin reference temperature. The thermal environment obtained with the SCS program is controlled only by the neonate's skin temperature changes. For each neonate, the program allows the attainment of a specific individual thermal equilibrium (Teq). Although the mean value of the thermal equilibrium level measured on 29 neonates does not differ significantly from the neutral air temperature defined from the charts of other researchers, individual values of Teq differed greatly among neonates of similar birthweight and postnatal age. When compared with on/off heating programs, the SCS system permits greater quiet sleep occurrence and seems to provide an optimal thermal environment. The results suggest that the skin temperature derivative heating program takes into account both the ambient and physiological factors affecting body temperature regulation of each neonate.

Automation↗

PubMed2005

Will transgenic plants adversely affect the environment?

Transgenic insecticidal plants based on Bacillus thuringiensis (Bt) endotoxins, on proteinase inhibitors and on lectins, and transgenic herbicide tolerant plants are widely used in modern agriculture. The results of the studies on likelihood and non-likelihood of adverse effects of transgenic plants on the environment including: (i) effects on nontarget species; (ii) invasiveness; (iii) potential for transgenes to 'escape' into the environment by horizontal gene transfer; and (iv) adverse effects on soil biota are reviewed. In general, it seems that large-scale implementation of transgenic insecticidal and herbicide tolerant plants do not display considerable negative effects on the environments and, moreover, at least some transgenic plants can improve the corresponding environments and human health because their production considerably reduces the load of chemical insecticides and herbicides.

Animals↗

PubMed1997

Program environments of self-help agencies for persons with mental disabilities.

Leaders of self-help agencies (SHAs) aspire to develop program environments that are different from community mental health agencies (CMHAs). This article addresses two questions. Do consumers' perceptions of SHAs approximate the characteristics leaders think ought to typify such agencies? Do SHA and CMHA consumers differ in their program perceptions? Using the Community-Oriented Program Environment Scale, leader expectations of ideal SHA environments were obtained from a national survey of 189 consumer-run agency heads, perceptions of actual environments from interviews with 310 SHA consumers, and perceptions of CMHAs from questionnaire responses of 779 consumers in 54 programs. SHA reality conforms to ideology in offering opportunities for consumers to experience involvement, support, and autonomy in the receipt of needed service. While showing only modest differences from CMHAs on relationship and treatment characteristics, SHA consumers differ in their perceived control over program rules, a fact previously found significant in promoting positive outcomes.

Adult↗

PubMed2004

Similarities and effectiveness of test environments in selecting and deploying desirable genotypes.

Rooted cuttings of 40 different clones (genotypes) of Picea abies (L.) Karst were planted in seven test environments (P, H, L, S, B, M and K) in northern Germany. Type-B genetic correlations between the pairs of test sites were estimated, and a cluster diagram based on inter-site genetic correlations for height was used to illustrate the general pattern of similarities among the test sites. Principal component analysis (PCA) showed that the first three principal components explained 97% of the variance in height, thereby providing a good summary of the relationships among the test sites. Test sites B and K accounted for a relatively high-and test sites H and M for a relatively low-proportion of genotype-environment interaction sums of squares and, consequently, for "ecovalence". "Moderator" and "instigator" test sites for interactions in different site combinations were detected. On the basis of several similarity measures, we observed two distinct groups: sites M-S-P formed one group, while sites K-L formed the other; sites H and B were closer to the first group. The empirical data indicated that a good test site should have the following features: (1) low interaction behaviour, (2) low coefficient of variation, (3) high genotypic selectivity, (4) high coefficient of determination, (5) high efficiency of expected gain. Based on these criteria, site M was determined to be the best test site for screening genotypes to be planted in other environments. We concluded that one broadly adapted vegetative propagation population of P. abies can be used for the potential planting environments in northern Germany.

Adaptation, Physiological↗

PubMed1998

The influence of environment on the induction of sensitization to the psychomotor activating effects of intravenous cocaine in rats is dose-dependent.

The acute psychomotor response and development of sensitization to amphetamine is attenuated if i.p. injections are given in the cage where a rat lives relative to when injections are given in a novel but physically identical test environment. Furthermore, when the environmental cues predicting i.p. injections are completely eliminated by using remotely activated i.v. injections in the home cage, 1.0 mg/kg amphetamine produces a very small acute response and no sensitization. The same treatments do produce sensitization if i.v. injections are signaled by placement of the rat in a novel test cage. The present experiment was designed to determine if there is a similar effect of environmental condition on the response to i.v. cocaine, and to what extent the effect may be dose-dependent. This was accomplished by comparing the psychomotor activating effects (rotational behavior) of repeated i.v. administrations of one of eight doses of cocaine (0.0, 0.3, 0.6, 1.2, 2.4, 3.6, 4.8, or 7.2 mg/kg) given in the home cage, with infusions of the same doses given in a novel test cage. There was no effect of environment on the acute psychomotor response to cocaine. There was, however, a significant effect of environment on the induction of sensitization. A higher dose of cocaine was required to induce sensitization when i.v. administrations were given in the home cage than when they were given in a physically identical but novel test environment. At high doses, however, cocaine induced sensitization regardless of environmental condition. The results suggest that the effect of this environmental manipulation is to shift the dose-effect curve for the induction of sensitization, and support the notion that the ability of psychostimulant drugs to induce sensitization can be modulated by the circumstances surrounding drug administration.

Animals↗

PubMed2005

Selection in a cyclical environment: possible impact of phenotypic lag on Darwinian fitness.

We investigated the effect of generation time (as controlled by chemostat flow rate) and temporal variability in nutrient (arginine) availability on selection at a regulatory locus in Escherichia coli. We first determined the fitness conferred by argR(K12) (which regulates the arginine regulon) relative to argR(B) (a weak constitutive) in constant environments at several generation times across a range of concentrations of arginine. The relative fitness of argR(K12) with respect to argR(B) declines with longer generation times in the absence of arginine yet becomes independent of generation time in the presence of excess arginine. Control experiments show this differential response in selection is entirely attributable to transcriptional regulation by argR(K12). Temporal variability in the supply of arginine generates fluctuations in selection. A simple model, based on the assumption that relative fitness tracks changes in arginine availability instantaneously, captures many of the features of the oscillating allele frequencies and accurately predicts the direction and intensity of selection in environments where arginine concentrations fluctuate frequently or infrequently. However, the model fails to predict the direction and intensity of selection in environments that fluctuate at moderate frequencies. This suggests that phenotypic lag, wherein cellular physiology changes more slowly than the environment, may be influencing the outcome of competition in this experimental system.

Arginine↗

PubMed2000

Effect of hypohydration on core temperature during exercise in temperate and hot environments.

The purpose of this study was to compare directly the physiological consequences of 5% hypohydration or euhydration during exercise in both temperate (23 degrees C) and hot (33 degrees C) environments. The subjects were eight male volunteers. Each performed four 1-h exercise bouts at 60% maximum oxygen uptake, one in each of the following conditions: hot-hypohydrated, hot-euhydrated, temperate-hypohydrated, and temperate-euhydrated. Heart rate (HR), rectal temperature (Tre), forearm blood flow, and oxygen uptake were measured after 20, 40, and 60 min exercise. Whole-body sweat rate was also determined for each exercise bout. Hypohydration increased Tre significantly (P<0.05) more in the hot environment (0.16 degrees C per 1% decrease in body mass) than in the temperate environment (0.08 degrees C per 1% hypohydration). Furthermore, compared with euhydration, hypohydration decreased forearm blood flow and whole-body sweat rate significantly more during exercise in the hot than in the temperate environment. The reductions in forearm blood flow and whole-body sweat rate appear to have decreased heat loss, thus accounting for the increase in Tre during exercise in the heat while hypohydrated. In conclusion, this study illustrates that the physiological consequences of hypohydration during exercise are exacerbated in the heat.

Adult↗

PubMed2004

Maternal investment in egg size: environment- and population-specific effects on offspring performance.

Geographic variation in maternal investment in offspring size can be adaptive if differences in investment translate into improved offspring performance in the given environments. We compared two moor frog, Rana arvalis, populations in the laboratory to test the hypothesis that investment in large eggs in populations originating from stressful (acid) environments improves offspring performance when reared in stressful (acid) conditions. We found that large initial size (hatchling mass) had moderate to strong, environment-dependent positive effects on larval and metamorphic traits in the acidic origin population, but only weak effects in the neutral origin population. Our results suggest that interactions between environmental conditions and initial size can be important determinants of individual performance, and that investment in large eggs is adaptive in acid environments. These findings emphasize the role of maternal effects as adaptations to environmental stress.

Adaptation, Physiological↗

PubMed2004

Survey of methicillin-resistant Staphylococcus aureus from neonates and the environment in the NICU.

Methicillin-resistant Staphylococcus aureus (MRSA) is a risk factor of nosocomial infection with compromised hosts including neonates. Currently, the prevalence of MRSA carriers among children is increasing in Japan. There are some reports of nosocomial infection caused by MRSA in a pediatric ward or neonatal intensive care unit (NICU). During 6 months (from January 2001 to June 2001), 37 MRSA strains were isolated from 37 neonates who were admitted in the NICU and 52 MRSA were strains isolated from NICU environments. We performed DNA typing of MRSA using an arbitrary primed-PCR method on these isolates. Thirty-seven clinical isolates were classified into four types (A type, 14; B type, 4; C type, 4; D type, 3; and others, 12). The A-type strains of MRSA continued to be isolated for more than 6 months. In the NICU environment, the detection rate of the A-type MRSA was 23.1% (12/52). The A-type strains were frequently isolated from environments around patients. The A-type strains of MRSA were prevalent in the NICU, probably due to nosocomial infection. Although none of the neonatal patients developed severe MRSA infection, the same genotype strains were persistently isolated during a period of more than 6 months from patients and the NICU environment around patients. Environmental control around neonatal patients is important to prevent nosocomial infection in the NICU.

Cross Infection↗

PubMed2006

The family environment and developmental psychopathology: the unique and interactive effects of depression, attention, and conduct problems.

Prior studies have found remarkable similarity in the family characteristics across a wide range of child psychopathologies. This study investigated the unique relationships between symptoms of depression, conduct problems/aggression, and inattention/hyperactivity and characteristics of the family environment. Parents and teachers completed multiple behavioral, emotional, and family measures to describe the characteristics of a community sample of 362 children. Results indicated that depression and conduct problems/aggression symptoms were uniquely associated with specific family environments. Both symptom clusters predicted family environments marked by less cohesiveness and intellectual/cultural pursuits and greater conflict. Depression alone was related to less expressiveness, independence, and activity, and to higher levels of control. Inattention/hyperactivity was not uniquely related to any aspect of family environment when controlling for depression and conduct/aggression problems, nor were combinations of symptoms. Findings are discussed with regard to implications for understanding clinical presentations, comorbidity, and treatment.

Attention Deficit Disorder with Hyperactivity↗

PubMed2005

Epistasis and genotype-environment interaction for quantitative trait loci affecting flowering time in Arabidopsis thaliana.

A major goal of evolutionary biology is to understand the genetic architecture of the complex quantitative traits that may lead to adaptations in natural populations. Of particular relevance is the evaluation of the frequency and magnitude of epistasis (gene-gene and gene-environment interaction) as it plays a controversial role in models of adaptation within and among populations. Here, we explore the genetic basis of flowering time in Arabidopsis thaliana using a series of quantitative trait loci (QTL) mapping experiments with two recombinant inbred line (RIL) mapping populations [Columbia (Col) x Landsberg erecta (Ler), Ler x Cape Verde Islands (Cvi)]. We focus on the response of RILs to a series of environmental conditions including drought stress, leaf damage, and apical damage. These data were explicitly evaluated for the presence of epistasis using Bayesian based multiple-QTL genome scans. Overall, we mapped fourteen QTL affecting flowering time. We detected two significant QTL-QTL interactions and several QTL-environment interactions for flowering time in the Ler x Cvi population. QTL-environment interactions were due to environmentally induced changes in the magnitude of QTL effects and their interactions across environments--we did not detect antagonistic pleiotropy. We found no evidence for QTL interactions in the Ler x Col population. We evaluate these results in the context of several other studies of flowering time in Arabidopsis thaliana and adaptive evolution in natural populations.

Arabidopsis↗

PubMed2005

Childhood temperament and family environment as predictors of internalizing and externalizing trajectories from ages 5 to 17.

Childhood temperament and family environment have been shown to predict internalizing and externalizing behavior; however, less is known about how temperament and family environment interact to predict changes in problem behavior. We conducted latent growth curve modeling on a sample assessed at ages 5, 7, 10, 14, and 17 (N = 337). Externalizing behavior decreased over time for both sexes, and internalizing behavior increased over time for girls only. Two childhood variables (fear/shyness and maternal depression) predicted boys' and girls' age-17 internalizing behavior, harsh discipline uniquely predicted boys' age-17 internalizing behavior, and maternal depression and lower family income uniquely predicted increases in girls' internalizing behavior. For externalizing behavior, an array of temperament, family environment, and Temperament x Family Environment variables predicted age-17 behavior for both sexes. Sex differences were present in the prediction of externalizing slopes, with maternal depression predicting increases in boys' externalizing behavior only when impulsivity was low, and harsh discipline predicting increases in girls' externalizing behavior only when impulsivity was high or when fear/shyness was low.

Adolescent↗

PubMed2005

Understanding mass school shootings: links between personhood and power in the competitive school environment.

This paper explores perspectives about certain individual and social characteristics that may contribute to school shootings by students. It begins with perspectives on individual/environment fit, arguing first that persons marginalized by their caregivers during their upbringing, and by their peers, are lacking in the social interactions that help develop ethical behavior. Our argument contends that lacking such interactions may result in the failure to develop a sound moral philosophy. Further, we argue that when such persons enter the highly competitive environment found in some suburban and rural schools, some will be continually and consistently marginalized, finding their means of self-expression and sense of significance subdued. Their need for self-expression and a sense of significance as persons will surface, but without the benefit of a moral philosophy to guide that expression, this may result in deviant means of expression, such as violence--even extraordinary violence. We do not attempt to identify a list of specific traits of school shooters, which might lead to the development of a profile of school shooters. Rather, we are concerned with the characteristics of the environment in which shootings might occur, and how students not fully prepared for that environment might react. Thus, this paper is an overview of how seeds of the neglect of the basic needs of personhood, when sown early in life, and nurtured by peers, might come to fruition in the fertile field of the competitive school environment.

Adolescent↗

PubMed1989

The dendritic morphology of pyramidal neurons in the rat hippocampal CA3 area. II. Effects of gender and the environment.

Sex differences in the dendritic structure of hippocampal CA3 pyramidal neurons were studied in Golgi-stained tissue from hooded rats that had been raised in either a relatively complex or an isolated environment from weaning for one month. Pyramidal neurons were sampled from both the short-shaft and long-shaft neuron categories as described by Fitch et al. The pattern of sex differences varies in different parts of the apical dendritic tree. In the apical tree proximal to the soma, females had more dendritic material than males. This pattern was attributable to the sex differences in the short-shaft neurons of rats from the more complex environment. The direction of sex differences was reversed in the distal apical dendritic tree where males had more dendritic material than females. As in the proximal dendritic tree, this pattern of sex differences stemmed from the short-shaft neurons of rats from the more complex environment. There were no sex differences in the basilar dendritic tree. Thus sex differences in the pyramidal neurons of hippocampal area CA3 vary with the portion of the dendritic tree examined, the type of pyramidal neuron, and the rearing environment of the animal.

Animals↗

PubMed1991

Plasticity of GFAP-immunoreactive astrocyte size and number in visual cortex of rats reared in complex environments.

Previous studies have indicated effects of postweaning rearing environment complexity on astrocyte nuclei. This study examined the effects of rearing for 10, 30 or 67 days in a complex (EC), social (SC) or individual cage (IC) environment upon glial fibrillary acidic protein (GFAP) immunoreactive astrocytes of the occipital cortex. EC rats exposed to their environment for 30 days or longer had a greater surface density of astrocytic processes (Sv) than SC or IC rats. The greater surface density of EC cortical astrocytes appeared to be due to an increase in the mean size of astrocytes after 30 days of differential environmental exposure. After 67 days of environmental exposure, however, the greater Sv appeared to be due to an increase in the number of astrocytes. Astrocytic plasticity appears to develop rather slowly during exposure to a complex environment and appears to involve two stages. The first stage is a hypertrophy of existing astrocytes and the second stage involves proliferation or retarded death of astrocytes. These changes may be related to brain information processing since astrocytes are known modulators of synaptic activity and may possibly serve as regulators of synaptic density.

Analysis of Variance↗