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PubMed2004

Differential selection of growth rate-related traits in wild barley, Hordeum spontaneum, in contrasting greenhouse nutrient environments.

Across-species comparisons show that inherent variation in relative growth rate (RGR) and its underlying traits are correlated with habitat productivity. In this study, we test the hypothesis that growth rate-related traits confer differential selective effects in contrasting nutrient environments. We specifically test whether high RGR is targeted by selection in nutrient-rich environments whereas low values of traits that underlie RGR [specific leaf area (SLA), leaf mass fraction and leaf area ratio (LAR)] confer a direct fitness advantage in nutrient-poor environments, resulting in selection of low RGR as a correlated response. We measured RGR, its underlying component traits, and estimated fitness in a range of wild barley (Hordeum spontaneum) accessions grown under high and low nutrient conditions. Selection on component traits differed between the two environments, while total selection of RGR was not significant. Using multiple regression and path analysis to estimate direct fitness effects, a selective advantage of high LAR and SLA was demonstrated only under nutrient-rich conditions. While supporting the view that observed associations between habitat richness and some RGR-component traits reflect adaptation to differing nutrient regimes, our data suggest that direct selection targets component traits rather than RGR itself.

Analysis of Variance↗

PubMed2000

The influences of family environment on personality traits.

In order to clarify the influences of family environment on the development of personality traits, 150 children (104 males and 46 females, mean age 13.2 +/- 2.4 years) who had been interviewed at the Child Guidance Clinic in Osaka were investigated. From 13 behavioral characteristics (activity, talkativeness, sociability, social skills, rule-keeping, will, aggression, emotional control, imagination, anxiety, maturity, intelligence, and neuroticism), factor analysis identified three personality traits: extraversion, maturity, and intellect. The effects of family environment (maternal and paternal participation in child rearing before and after 4years of age, child-rearing style, parental relationship, sibling relationship, number of siblings, birth order, and socioeconomic status) on these personality traits were examined based on a structural equation model. The results found, first, that extraversion was negatively associated with overprotection/interference and with maternal participation in child rearing. Maturity correlated with high socioeconomic status, appropriate child-rearing style, and paternal participation in child rearing. Intellect was related to high socioeconomic status and maternal participation in child rearing. Second, path analysis with selected variables revealed that 8% of variance in extraversion, 14% in maturity, and 10% in intellect was due to family environment. Third, children with high introversion or high intellect had stronger influences from family environment than did those with high extraversion or low intellect.

Adolescent↗

PubMed2001

Development of an innovative tool to assess hospital learning environments.

Nursing as a profession has evolved in response to societal needs for well-prepared practitioners who provide quality care to the needed in episodes of illness, and promote health among all age groups. Clinical practice enables the student to develop competencies in the application of knowledge, skills, and attitudes to clinical field situations. The clinical learning environment is a multidimensional entity with a complex social context. Previous research on clinical learning environment was examined, yet minimal studies have been conducted on hospital learning environments from the psychosocial educational perspective. With the mission to maximize nursing students' clinical learning experiences, the author developed and validated the Clinical Learning Environment Inventory (CLEI) based on the theoretical framework in psychosocial education. It is envisaged that this tool will assist the nurse professional to facilitate nursing students to achieve a productive clinical practice. This paper highlights the need and details the conceptual framework in the development of the CLEI. Although it is not presented as a research based paper, some statistical data are included to verify the reliability and validity of the newly-developed instrument.

Education, Nursing↗

PubMed2004

Geographical slant facilitates navigation and orientation in virtual environments.

Theoretical considerations and earlier experimental findings indicate that traveling over slanted terrain can lead to an enrichment of the perceived spatial cues relevant for navigation. We investigated the proposed facilitation of a uniformly slanted environment on navigation and orientation performance with a virtual environment presented on a large 180 degrees screen, using as material a virtual town with eight places and twenty-four landmarks. In the control condition, this town was placed on a flat surface; in the two experimental conditions, the town was placed on a slope with a uniform angle of 4 degrees. Pedaling on a bicycle simulator, participants first explored the environment, then solved navigation tasks, pointed from various positions to distant landmarks, judged the relative elevation of pairs of distant landmarks from memory, and finally drew a sketch map of the environment. In comparison to the control condition, the number of navigation errors was significantly lower in the slanted conditions, and the deviations in the pointings to distant landmarks were massively reduced. Participants from the slant conditions also showed good knowledge of the relative elevations of pairs of distant locations. However, no differences in map-drawing quality were found. The results lend additional support to the proposition that our spatial knowledge, which is used in navigation and orientation, contains vertical information.

Adolescent↗

PubMed2005

The influence of restricted viewing conditions on egocentric distance perception: implications for real and virtual indoor environments.

We carried out three experiments to examine the influence of field of view and binocular viewing restrictions on absolute distance perception in real-world indoor environments. Few of the classical visual cues provide direct information for accurate absolute distance judgments to points in the environment beyond about 2 m from the viewer. Nevertheless, in previous work it has been found that visually directed walking tasks reveal accurate distance estimations in full-cue real-world environments to distances up to 20 m. In contrast, the same tasks in virtual environments produced with head-mounted displays (HMDs) show large compression of distance. Field of view and binocular viewing are common limitations in research with HMDs, and have been rarely studied under full pictorial-cue conditions in the context of distance perception in the real-world. Experiment 1 showed that the view of one's body and feet on the floor was not necessary for accurate distance perception. In experiment 2 we manipulated the horizontal and the vertical field of view along with head rotation and found that a restricted field of view did not affect the accuracy of distance estimations when head movement was allowed. Experiment 3 showed that performance with monocular viewing was equal to that with binocular viewing. These results have implications for the information needed to scale egocentric distance in the real-world and reduce the support for the hypothesis that a limited field of view or imperfections in binocular image presentation are the cause of the underestimation seen with HMDs.

Adult↗

PubMed2001

Contribution of individual random mutations to genotype-by-environment interactions in Escherichia coli.

Numerous studies have shown genotype-by-environment (GxE) interactions for traits related to organismal fitness. However, the genetic architecture of the interaction is usually unknown because these studies used genotypes that differ from one another by many unknown mutations. These mutations were also present as standing variation in populations and hence had been subject to prior selection. Based on such studies, it is therefore impossible to say what fraction of new, random mutations contributes to GxE interactions. In this study, we measured the fitness in four environments of 26 genotypes of Escherichia coli, each containing a single random insertion mutation. Fitness was measured relative to their common progenitor, which had evolved on glucose at 37 degrees C for the preceding 10,000 generations. The four assay environments differed in limiting resource and temperature (glucose, 28 degrees C; maltose, 28 degrees C; glucose, 37 degrees C; and maltose, 37 degrees C). A highly significant interaction between mutation and resource was found. In contrast, there was no interaction involving temperature. The resource interaction reflected much higher among mutation variation for fitness in maltose than in glucose. At least 11 mutations (42%) contributed to this GxE interaction through their differential fitness effects across resources. Beneficial mutations are generally thought to be rare but, surprisingly, at least three mutations (12%) significantly improved fitness in maltose, a resource novel to the progenitor. More generally, our findings demonstrate that GxE interactions can be quite common, even for genotypes that differ by only one mutation and in environments differing by only a single factor.

Biological Evolution↗

PubMed1996

Iron nutrition and anaemia in a malaria-endemic environment: haematological investigation of the Gidra-speaking population in lowland Papua New Guinea.

Blood examination was conducted for the four Gidra-speaking village groups in Papua New Guinea, who were characterized by high Fe intake and high malaria prevalence with marked inter-village differences. The northern riverine villagers, whose Fe intake was higher than the other three village groups, did not suffer from Fe-deficiency anaemia in their malaria-endemic environment; nor did the inland villagers, with their second highest Fe intake and their malaria-free environment, suffer from Fe-deficiency anaemia. However, several individuals of the southern riverine village suffered from anaemia in a malaria-endemic environment, although their Fe intake was almost the same as the inland villagers'. A considerable proportion of the coastal villagers were anaemic, reflecting the lowest Fe intake and the highest malaria prevalence. An inter-village comparison of the relationships between haemoglobin levels and transferrin saturation revealed that the southern riverine villagers needed smaller amounts of circulating Fe for erythropoiesis than the northern riverine and inland villagers, reflecting the long-term human-environment conditions such as the density of malaria vectors and the people's dietary habits. Fe supplementation was not judged effective against hypoferraemia and/or anaemia in such a population. As the incidence of malaria had no significant long-lasting effect on Fe stores or circulating Fe concentration, but did have an effect on anaemia, the hypothesis that malaria causes a transfer of Fe from the blood to parenchymal tissues as a defence against infectious diseases was not supported.

Anemia, Iron-Deficiency↗

PubMed1976

Sibsize, family environment, cognitive performance, and affective characteristics.

The study examined to what extent relationships between sibsize and the cognitive and affective chaarcteristics of children were mediated by family environments. The Alice Heim nonverbal intelligence test (AH4), the Watts Vernon English test, and the Vernon graded mathematics test were used to assess the cognitive performance of 15-year-old children (383 boys and 396 girls). The Ss formed part of a longitudinal national study of English school children. Also schedules were administered to measure children's educational and occupational aspirations, self-concepts, and attitudes toward school. From parental interviews a family environment index consisting of both distal and proximal measures was constructed. The Jackknife technique was used in the analysis to adjust significance levels. Regression surface analysis indicated that at each environment level, sibsize was related only to the English achievement of girls and boys and to the aspirations of girls. However, the shapes of the surfaces suggest that if parents create differential learning environments for different siblings then the behaviors of the siblings are likely to vary, which provides tentative support for the confluence model of sibsize influences on the behaviors of children.

Adolescent↗

PubMed1998

A transitional living environment for persons with brain injuries: staff and client perceptions.

Given increasing interest in social ecology and the impact of environmental factors upon rehabilitation outcomes, the purpose of this study was to begin to document the characteristics of a particular environment designed to meet the needs of persons with traumatic brain injuries. Staff and clients at the Transitional Living Centre of Kingston, Ontario (TLC), a community based post-acute rehabilitation programme providing both residential and day programmes for adults who have acquired brain injuries participated in this study by completing the Community-Oriented Programme Environment Scale (COPES). While COPES subscale scores for clients and staff were within the average range, the results of a multivariate analysis of variance indicated that client and staff perceptions of the TLC environment differed significantly on two subscales within the Personal Development Dimension (i.e., Personal Problem Orientation, Anger and Aggression) and on one subscale under the System Maintenance Dimension (i.e., Staff Control). The results of this study suggest that future research should consider the impact of staff and client perceptions on the effectiveness of the therapeutic environment of brain injury programmes.

Activities of Daily Living↗

PubMed1981

Determinants of person-environment congruence in institutionalized elderly men and women.

This study was designed to obtain information potentially of value in understanding an modifying the impact of the social environment of the perceived quality of like among institutionalized aged persons. It was hypothesized that Person-Environment (P-E) congruence, as assessed by the Environmental Perception, Preference and Importance Scale (EPPIS), would be related to (1) sex integration/segregation makeup of the health related facility (HRF) living units, and (2) quantity of social interaction between staff and residents. Analysis of sex by unit sex-type interaction for 60 residents' Person-Environment (P-E) congruence scores revealed that elderly females on sex-integrated units reported a higher level of P-E congruence than those residing on female-only units; males on sex-integrated units, in contrast, reported a poorer level of P-E congruence than males on sex -segregated units. Furthermore, behavioral observations of staff-resident verbal interactions confirmed the hypothesis that residents living on units with high staff-resident interaction perceived the environments more congruent with their preferences than residents on units low in verbal interaction. The observed relationships between the P-E congruence measure, resident-staff interaction, and unit sex-type were taken as further support for the relevance and value of the EPPIS measure as a tool for assessing and improving the institutional milieu.

Aged↗

PubMed2006

Perceived social environment and quality of life among people living with HIV/AIDS in northern Thailand.

Efforts have been made to improve the social environment of people living with HIV/AIDS (PLWHA) in Thailand but have not been assessed in terms of their quality of life (QOL). In this study, we preliminarily examined the relationship between PLWHA's perception of social environment and QOL. The participants of this study were 200 PLWHA who belonged to the self-help groups in Chiang Mai province, northern Thailand. We collected data in face-to-face interviews using a structured questionnaire. The QOL was measured using a Thai version of the Medical Outcomes Study HIV Health Survey. Those who perceived themselves as well accepted by the community, perceived health services accessible or someone's help available, tended to have better QOL in terms of mental health. Community acceptance was most significantly related to QOL. Stratified analyses revealed similar relationships between perceived social environment and QOL among symptomatic and non-symptomatic participants but the relationships appeared weaker among men than women. In sum, our preliminary findings suggest that supportive social environment, especially community acceptance, is important for mental aspects of PLWHA's QOL irrespective of the disease stages and for women who usually take on multiple roles in the Thai traditional family.

Adult↗

PubMed2005

Drug use, misuse, and the urban environment.

Urbanization is probably the single most important demographic shift world-wide throughout the past and the new century and represents a sentinel change from how most of the world's population has lived for the past several thousand years. As urban living becomes the predominant social context for the majority of the world's population, the very ubiquity of urban living promises to shape health directly and to indirectly affect what we typically consider risk factors or determinants of population health. Although a growing body of research is exploring how characteristics of the urban environment may be associated with health (e.g. depression) and risk behaviours (e.g. exercise patterns), relatively little research has systematically assessed how the urban environment may affect drug use and misuse. In this paper we will propose a conceptual framework for considering how different characteristics of the urban environment (e.g. collective efficacy, the built environment) may be associated with drug use and misuse, summarize the existing empiric literature that substantiates elements of this framework, and identify potential directions for future research.

Health Services Accessibility↗

PubMed2006

An investigation of the housing environment for persons with asthma and persons without asthma.

Asthma is a chronic disease affected by environmental factors that may increase symptoms that impact on a persons' well-being. An important issue in occupational therapy is to improve the relationship between a person's functional capacity and the physical environment. The aim of the study was to compare the housing environment of persons with asthma (cases, n = 49) and persons without asthma (controls, n = 48), with regard to building construction and condition, physical, chemical and biological factors, and cleaning routines. A secondary aim was to compare different types of accommodation within cases and controls. A specialist team, including a construction engineer, a biological scientist, and an occupational therapist, conducted the study. Data were collected using protocols, as well as a number of established technical methods from the field of occupational and environmental medicine. The primary results showed no major differences in the housing environment between the two groups. However, in individual homes environmental factors at levels that could increase symptoms were identified. When single-family houses were compared with multi-family houses, significant differences were found indicating that preventive interventions may be needed in some single-family houses. Further studies are needed to clarify the person-environment relationship for persons with asthma, focusing on their ability to perform daily activities.

Activities of Daily Living↗

PubMed1993

Extreme environments and exobiology.

Ecological research on extreme environments can be applied to exobiological problems such as the question of life on Mars. If life forms (fossil or extant) are found on Mars, their study will help to solve fundamental questions about the nature of life on Earth. Extreme environments that are beyond the range of adaptability of their inhabitants are defined as "absolute extreme". Such environments can serve as terrestrial models for the last stages of life in the history of Mars, when the surface cooled down and atmosphere and water disappeared. The cryptoendolithic microbial community in porous rocks of the Ross Desert in Antarctica and the microbial mats at the bottom of frozen Antarctic lakes are such examples. The microbial communities of Siberian permafrost show that, in frozen but stable communities, long-term survival is possible. In the context of terraforming Mars, selected microorganisms isolated from absolute extreme environments are considered for use in creation of a biological carbon cycle.

Antarctic Regions↗

PubMed2004

The relationship between self-destructive behaviour and nursing home environment.

The aim of this study was to explore the relationship between self-destructive behaviour and nursing home environment. We performed a cross-sectional study comprising 647 residents in 11 nursing homes in Sydney, Australia using the Harmful Behaviours Scale (HBS), Abbreviated Mental Test Scale and the Resident Classification Index. The Directors of Nursing completed a questionnaire that rated physical design, staff and resident characteristics and demographics were obtained from nursing home records. On regression analysis a greater number of design features for frail and residents with dementia in general, and increased security measures were associated with greater HBS total score and risk-taking and passive self-harm subscales. A residential environment in which the residents were more functionally dependent and more likely to be in a shared room, managerial policies less geared towards managing difficult behaviour and less staff availability and training were associated with the 'uncooperativeness' factor. There were no significant predictors of the other two factors. The relationship between nursing home environment and self-destructive behaviours and the environment is complex and there needs to be an individualized approach to placement.

Adaptation, Psychological↗

PubMedDate not supplied

The relationship between school environment and participation for students with disabilities.

The aim of this study was to investigate the relationship between participation in school activities of students with disabilities and their school environment. Children and youths with disabilities rated their own participation in school activities while teachers and special education counsellors rated the student's school environment. Statistical methods used in this study were the Pearson's correlation coefficient and one-way-ANOVA. The results revealed that neither the amount of support given nor the general school environment was statistically related to students' participation. Further, the individual's specific environment, especially when rated as availability to activities by the students themselves, was related to students' participation. This might indicate that when investigating important environmental factors related to participation, students' own perceptions of his/her niches is important to investigate. The support students were given related more to type and number of disabilities than to students' participation.

Adaptation, Psychological↗

PubMed2005

Environment, area, and diversification in the species-rich flowering plant family Iridaceae.

Phylogenetic analyses provide a means to explore evolutionary explanations for regional variation in species richness. The environment might also explain much of the previously unexplained imbalance of phylogenetic trees. We use data on geographic distribution and phylogenetic affinity to examine correlates of species richness among genera of irises (family: Iridaceae). Irises display strong phylogenetic imbalance, with a few clades containing a disproportionate number of species, most notably those found in the dry Mediterranean climate of the Cape of South Africa. The abiotic environment and area are strong predictors of iris species richness, but environment alone is insufficient to explain the high diversity of Cape clades. One possible explanation is that the interaction between biological traits and environment resulted in the unusually high diversification rates in the region.

Biodiversity↗

PubMed2001

Commentary: facing the challenge of gene-environment interaction: the two-by-four table and beyond.

As a result of the Human Genome Project, epidemiologists can study thousands of genes and their interaction with the environment. The challenge is how to best present and analyze such studies of multiple genetic and environmental factors. The authors suggest emphasizing the fundamental core of gene-environment interaction-the separate assessment of the effects of individual and joint risk factors. In the simple analysis of one genotype and an exposure (both dichotomous), such study can be summarized in a two-by-four table. The advantages of such a table for data presentation and analysis are many: The table displays the data efficiently and highlights sample size issues; it allows for evaluation of the independent and joint roles of genotype and exposure on disease risk; and it emphasizes effect estimation over model testing. Researchers can easily estimate relative risks and attributable fractions and test different models of interaction. The two-by-four table is a useful tool for presenting, analyzing, and synthesizing data on gene-environment interaction. To highlight the role of gene-environment interaction in disease causation, the authors propose that the two-by-four table is the fundamental unit of epidemiologic analysis.

Environment↗