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PubMed1990

Alcohol consumption and self-reported drinking-related problem behaviors as related to sex, work environment, and level of education.

This study examined the relation of sex, work environment, and level of education to self-reported alcohol-related problem behaviors and estimates of weekly consumption. 216 employees of various establishments located in the eastern United States participated in the study, which involved answering a 17-item questionnaire. It was hypothesized that men would report more problems and greater consumption than women, college educated individuals more than people with no college background, and employees of alcohol-related environments more than those of nonalcohol-related environments. The results confirmed the predictions for environment and sex. There were also significant interactions between sex and environment and for sex and education concerning consumption. The triple interaction was also significant for the consumption variable. Further investigation is needed to determine the ramifications for both employers and employees of alcohol-related areas.

Adult↗

PubMed2005

Effects of genotype x environment interaction on genetic gain in breeding programs.

Genotype x environment interaction (G x E) is increasingly important, because breeding programs tend to be more internationally oriented. The aim of this theoretical study was to investigate the effects of G x E on genetic gain in sib-testing and progeny-testing schemes. Loss of genetic gain due to G x E was predicted for different values of heritability, number of progeny per dam, number of progeny per sire, proportion of selected sires, and population size in the selection environment. Two environments were considered: a selection environment (SLE) and a production environment (PDE). The breeding goal was only for performance in PDE. A pseudo-BLUP selection index was used to predict genetic gain. Recording of half-sibs or progeny in PDE limited the loss in genetic gain in PDE due to G x E between SLE and PDE. Progeny-testing schemes had less loss in genetic gain than sib-testing schemes. Higher heritability increased the loss in genetic gain, whereas increasing the number of progeny per sire in PDE decreased the loss in genetic gain. The number of progeny per sire required to minimize loss in genetic gain due to G x E was greater for sib-testing schemes than for progeny-testing schemes. More progeny per dam slightly increased the loss in genetic gain. Genetic gains for sex-limited and carcass traits were less affected by G x E than traits measured on both sexes. Loss in genetic gain was due to decreased accuracy of selection in most situations, but it was due to decreased selection intensity in situations with small population size and a low proportion of selected sires. It was concluded that recording performance of relatives in PDE minimizes loss in genetic gain due to G x E, and that progeny-testing schemes rather than sib-testing schemes are preferable in situations with low to moderate heritability (h(2) <or= 0.3), relatively short generation interval of progeny-tested sires (L(prog)/L(sib) <or= 1.7), and moderate to severe G x E interaction (r(g) <or= 0.8).

Animals↗

PubMed1984

Perceived marital and family environment of opiate addicts.

Addicts have described their family environment as providing inadequate modeling of social and role skills, while having high expectations for achievement. These self-reports have not been compared to either the reports of other family members or observer ratings of addict families. Observer ratings are important because addicts have also described their families as having significantly less conflict than normative families. We administered the Moos Family Environment Scale (FES) to 73 addicts and found that our addicts' scores supported the previous descriptions of addicts' perceived family environment. Addicts' perceived family environment differed from normative samples. They perceived their family as providing little preparation for social roles, while expecting high achievement. When addicts' wives or mothers completed the FES (n = 27), they disagreed with the addicts' perceptions of having high expectations for achievement in the marriage or family. Relative to their mothers and wives, the addicts seemed to be insensitive to the lack of effective organization and limit setting in either their family of origin or marriage. However, the mothers and wives agreed with the addicts in reporting low levels of conflict, but behavioral ratings of the married addicts and their wives (n = 16) showed a poor correlation between the observed behavior and the couples' perceptions. Furthermore, the level of conflict appeared to be above rather than below normative samples. Thus, addicts' perceptions of their family environment demonstrated significant discrepancies from the perceptions of their wives and mothers and from ratings of their marital behavior.

Adult↗

PubMedDate not supplied

Reconceptualizing the environment of the individual with a chronic mental illness.

The individual with a chronic illness frequently experiences a variety of environmental settings throughout the illness and treatment process. Although it is congruent with current nursing theory development to view environment in a broad context, nurses may fail to appreciate the continuity of environments experienced by their clients. This article argues for a reconceptualization of the environment that explicitly considers the continuity of environments experienced by the client with a chronic mental illness. This will assist nurses in determining the supportive and nonsupportive aspects of their clients' environments.

Continuity of Patient Care↗

PubMedDate not supplied

Environments and addiction: a proposed taxonomy.

When reviewing the broad area that relates environments to addiction one is faced with an enormous volume of research with differing environmental and psychosocial factors, contrasting populations, a variety of addictive substances, and a range of addiction processes. For all these factors, there are important outcome variables. To survey this disparate literature, it is helpful to use a multiaxial model as a framework or taxonomy. In this way it is possible to see the effects that environments, broadly conceived, exert on addictive behaviors. A variety of environments is considered: interpersonal, organizational, cultural and physical, as one axis or dimension. The influence of this dimension on a second dimension relating to type of addiction is also examined. Finally, a dimension pertaining to the "life history" of addictions, from acquisition through maintenance, cessation, and relapse is considered in relation to the first two dimensions. While a variety of environmental factors affect addictive behaviors, current research indicates the need to take individual differences, cognitive mediation, and the interaction of the person with the environment into account. Significant areas that need further exploration are the failure of addictions to occur in some environments, and the development of secondary prevention approaches. Implications for intervention and directions for future research are suggested.

Cross-Cultural Comparison↗

PubMed1996

Social influences: effects of the social environment on the use of alcohol and other drugs.

The research aimed to measure social influences produced by the differential effects of "high use" and "low use" environments on students' vulnerability to substance misuse. Each environment was represented by 3,000 students sampled from high and low use colleges. The social influences were measured by comparing vulnerability/resistance scores derived through a cognitive mapping strategy of the Associative Group Analysis method. Using an advanced system of software, empirical measures of students' propensities to use or not to use harmful substances were obtained by comparing hundreds of spontaneous responses elicited from individual respondents to the response distributions of reference groups of frequent alcohol/drug users and nonusers. In all comparisons, students with higher levels of reported use also showed higher vulnerability. In all comparisons, students in the high use environment showed significantly higher levels of vulnerability than students in the low use environment. ANOVA results indicated the vulnerability of students was significantly related to (high vs low use) campus environment as well as to marijuana use, alcohol use, and gender. Measuring vulnerability as a function of social influences opens numerous applications in proactive prevention.

Adolescent↗

PubMed2004

Factors that cause genotype by environment interaction and use of a multiple-trait herd-cluster model for milk yield of Holstein cattle from Brazil and Colombia.

Descriptive herd variables (DVHE) were used to explain genotype by environment interactions (G x E) for milk yield (MY) in Brazilian and Colombian production environments and to develop a herd-cluster model to estimate covariance components and genetic parameters for each herd environment group. Data consisted of 180,522 lactation records of 94,558 Holstein cows from 937 Brazilian and 400 Colombian herds. Herds in both countries were jointly grouped in thirds according to 8 DVHE: production level, phenotypic variability, age at first calving, calving interval, percentage of imported semen, lactation length, and herd size. For each DVHE, REML bivariate animal model analyses were used to estimate genetic correlations for MY between upper and lower thirds of the data. Based on estimates of genetic correlations, weights were assigned to each DVHE to group herds in a cluster analysis using the FASTCLUS procedure in SAS. Three clusters were defined, and genetic and residual variance components were heterogeneous among herd clusters. Estimates of heritability in clusters 1 and 3 were 0.28 and 0.29, respectively, but the estimate was larger (0.39) in Cluster 2. The genetic correlations of MY from different clusters ranged from 0.89 to 0.97. The herd-cluster model based on DVHE properly takes into account G x E by grouping similar environments accordingly and seems to be an alternative to simply considering country borders to distinguish between environments.

Analysis of Variance↗

PubMed1998

Independent reference frames in human spatial memory: body-centered and environment-centered coding in near and far space.

Our apparently seamless experience of the spatial environment seems to be derived from information coded across a variety of spatial reference frameworks, each tied to the metric of a different sensory or motor system. A fundamental distinction is that between body-centered and environment-centered reference frameworks. This study reports the first clear evidence of a behavioral dissociation between body-centered and environment-centered coding in human adults. Subjects, seated in a rotating chair with closed eyes, were required to point to remembered, auditorily presented target locations. The subjects were rotated between the presentation and recall of targets. Targets were held stationary with respect to either body-centered or environment-centered spatial coordinates. Prior to recall, subjects were required to point to a series of prelearned distractor locations, which also remained fixed with reference either to the subject's body or to the stationary environment. Memory for the target locations was selectively impaired when distractor locations were specified within the same spatial reference frame as the target, regardless of whether target and distractor locations were near to or distant from the subjects. In contrast, distractor locations specified in a different reference frame from that of the target had either little or no effect on memory for target locations.

Adult↗

PubMed2003

Accompaniment needs of first year nursing students in the clinical learning environment.

The clinical learning environment creates many opportunitics for student learning and the development of critical competencies in the nursing profession. The learning that takes place in this environment, however, confronts the first year nursing student with challenges that are absent from the classroom situation and causes the student to experience a significant amount of uncertainty and anxiety. The study revealed that the students experience uncertainty due to the lack of opportunities to develop competence in providing nursing care. The contributing factors towards this experience are: unavailability and inaccessibility of staff due to time constraints; shortage and/or absence of equipment to fulfil nursing duties and meet the needs of patients; conflict in the expectations of nursing school personnel and clinical nursing personnel in hospitals, as well as a lack of awareness among senior professionals of the needs and problems of first year nursing students in the clinical health care environment. Furthermore the students experienced the nature of the clinical learning programme as disrupting the continuity in patient care learning experiences, and the guidance and support by nursing personnel in the clinical learning environment as inadequate. The aim of this study was to reflect the importance of effective accompaniment by tutors/mentors, personnel in the clinical environment and any other person involved in the education of the first year nursing student, to prepare and enable him/her to become a knowledgeable, safe, competent nursing practitioner.

Adolescent↗

PubMedDate not supplied

Distribution of learning styles and preferences for learning environment characteristics among Emergency Medical Care Assistants (EMCAs) in Ontario, Canada.

INTRODUCTION: In Ontario, Canada, Emergency Medical Care Assistants (EMCAs) have many opportunities for continuing education. However, little is known about how EMCAs learn. OBJECTIVES: The intent of this study was to explore the distribution of learning styles, preferences for major learning environment characteristics, and the associations between these two factors among the EMCA population in Ontario, Canada. METHODS: Following review of the literature, a 32-item survey of learning environment characteristics was constructed to measure the respondents' preferences. Using a random number generator, 386 EMCAs were selected for participation. Each received: a) an explanatory cover letter; b) a copy of the Kolb Learning Style Inventory (LSI) questionnaire; c) a second questionnaire consisting of learning environment characteristics; and d) a stamped, return addressed envelope. Completed surveys were scored to determine the respondent's Learning Style. The LSI and Learning Environment survey results were entered into a data base and subjected to Dual Scaling analysis in order to 1) Identify the distribution of learning styles; and 2) Explore associations between styles and environmental characteristics. RESULTS: A total of 75 completed surveys were returned, each of the four styles of learning (Converger; Diverger; Assimilator; and Accommodator) were identified in the sample. Dual Scaling analysis indicated a noteworthy association (R(jt) correlation > 0.300) between learning style and 10 of the 32 environmental characteristics. The data describe the usefulness of each of the learning styles. Accommodators believed courses with a strong emphasis on practical applications and working in groups to be very useful, but were less interested in courses with a strong emphasis on theory. Assimilators felt lectures and courses with a strong emphasis on theory very useful, but were less interested in providing input into course objectives. Divergers found that a lot of verbal explanation is useful, but were less interested in working with teachers who act as coaches. Convergers believed that working with teachers who act as coaches is useful. They also preferred courses with a strong emphasis on practical applications, but were less interested in courses with a strong emphasis on theory. CONCLUSIONS: The findings in this study, provide some additional insight into the connections between learning style and elements of the learning environment, and their application may contribute to operationalizing learning theory.

Data Collection↗

PubMed2000

Myopia: gene-environment interaction.

INTRODUCTION: Myopia has reached epidemic proportions in Japan, Hong Kong, Taiwan and Singapore. This review summarises the evidence for environmental and genetic factors as well as gene-environment interaction for myopia for both epidemiologic studies as well as animal models. METHODS: A literature review was conducted after a Medline search on articles on the genetic or environmental aetiology of myopia in animal or epidemiologic studies. Articles on the methodology of gene-environment studies were also reviewed. All articles reviewed were articles published in peer-reviewed journals. RESULTS: Cross-sectional studies have found a positive association between myopia and near work activity such as reading and writing. Likewise, laboratory research has shown that environmental factors such as visual deprivation may lead to the development of myopia in animals. While linkage studies in humans are currently being conducted to identify possible markers for myopia in the human genome, several neurotransmitters, modulators and growth factors that influence refractive development have already been identified in animal models that may help identify candidate genes. Epidemiologic studies have also evaluated the combined effects of hereditary factors, environmental factors and gene-environment interaction on myopia development. CONCLUSIONS: Both genes and environmental factors may be related to myopia. There are no conclusive studies at present, however, that identify the nature and extent of possible gene-environment interaction. Further linkage analysis, affected sib-pair studies, and family-based association studies may better identify the nature of gene-environment interaction.

Animals↗

PubMed1999

Engineering plants for spaceflight environments.

The conversion efficiency of radiation into biomass and yield has steadily increased for centuries because of continued improvement in both plant genetics and environmental control. Considerable effort has gone into improving the environment for plant growth in space, but work has only begun to engineer plants for spaceflight. Genetic manipulation offers tremendous potential to improve our ability to study gravitational effects. Genetic manipulation will also be necessary to build an efficient regenerative life support system. We cannot fully characterize plant response to the spaceflight environment without understanding and manipulating their genetic composition. Identification and selection of the existing germplasm is the first step. There are thousands of cultivars of each of our major crop plants, each specifically adapted to a unique environment on our planet. Thousands of additional lines are held in national germplasm collections to maintain genetic diversity. Spaceflight imposes the need to tap this diversity. Existing lines need to be evaluated in the environment that is characteristic of closed-system spaceflight conditions. Many of the plant growth challenges we confront in space can be better solved through genetic change than by hardware engineering. Ten thousand years of plant breeding has demonstrated the value of matching genetics with the environment. For example, providing continuous light can increase plant growth in space, but this often induces calcium deficiencies because Ca is not supplied by guttation during a dark period. This deficiency cannot be eliminated through increased root-zone and foliar Ca applications. It can be solved, in wheat, through genetic selection of lines that do not have the deficiency. Subsequent comparison of lines with and without the Ca deficiency has also helped us understand the nature of the problem.

Ecological Systems, Closed↗

PubMed1966

Survival and growth of potential microbial contaminants in severe environments.

Studies conducted in our laboratory have established that a number of potential soil microbes could survive a simulated Martian environment. In view of the uncertainty of the Martian environment and the importance of noncontamination of extraterrestrial bodies, studies were performed with common soil microbes to determine the minimal environment necessary to produce a complete growth cycle. The effects of diurnal temperature cycling (+25 degrees C to -65 degrees C) and of limiting concentrations of moisture and oxygen on spore germination, vegetative growth and sporulation of Bacillus cereus and B. subtilis have been determined. The results indicated that diurnally temperature-cycled heat-shocked spores of B. cereus in the simulated Martian atmosphere: 1) survived when the moisture concentration was < or = 4%; 2) germinated but became nonviable when the moisture concentration was > 4 < 8%; 3) germinated with subsequent vegetative growth when a) the moisture concentration was > or = 8%, and b) the concentration was > or = 6% and the partial pressure of oxygen was 15 mm; 4) sporulated when the moisture concentration was > or = 6% and the partial pressure of oxygen was 15 mm. Similar data for heat-shocked spores of B. subtilis in the simulated Martian atmosphere, diurnally temperature-cycled, indicated that the spores: 1) survived when the moisture concentration was > or = 6%; 2) germinated but became nonviable when the moisture concentration was > 1 < 4%; 3) germinated with subsequent vegetative growth when the moisture concentration was > or = 8%; 4) sporulated when the moisture concentration was > or = 6% and the partial pressure of oxygen was > or = 10 mm. Preliminary studies with B. cereus and B. subtilis spores produced in the simulated Martian environment and reintroduced into this environment indicated that vegetative cell growth and sporulation were normal. These data are discussed with regard to the probability of contamination of extraterrestrial bodies.

Bacillus cereus↗

PubMed1965

Response of microorganisms to a simulated Martian environment.

A study was undertaken to determine whether terrestrial microorganisms can survive in a simulated Martian environment. The ultimate objective is to establish whether earth organisms can contaminate Mars. In addition, any demonstration of survival and growth in a simulated Martian environment will provide information relating to the biology of Mars. In the experimental design, exhaustive consideration was given to the duplication of the known and the theoretical environmental parameters of Mars. These included composition of the soil and the atmosphere, barometric pressure, moisture content, solar radiation, and diurnal temperature extremes. Based upon these considerations, a simulated Martian summer environment was defined and used in the experiments. One group of microorganisms was selected from culture collections on the basis of their known characteristics. The other group was made of microorganisms isolated from soils. The soil samples were obtained from the Antarctic, from New Mexico, and California deserts, and from the Colorado tundra. The studies showed that a number of microorganisms can survive the simulated Martian environment. However, no substantial growth under such conditions could be demonstrated. The ability of microorganisms to form spores as a mechanism for survival will be discussed. Also, experiments utilizing augmented environments to establish minimum environmental conditions which will permit growth will be described.

Atmosphere↗

PubMed2002

[Dynamic changes of SOD and MDA in canine limbs with gunshot wound in hot and humid environment: an experimental study].

OBJECTIVE: To study the dynamic changes in lipid peroxidation and the activity of antioxidative enzyme in canine limbs with gunshot wound in hot and humid environment. METHODS: Eighteen dogs with gunshot wound were randomly assigned into 3 groups with equal numbers. Dogs observed after injury in normal environment was designated as NE group, those in hot and humid environment as HHE group and those in hot and humid environment with preceding heat acclimatization training as HA group. Contents of superoxide dismutase (SOD) and malonaldehyde (MDA) in both the peripheral blood and muscular tissues from gunshot wound tract were measured at 0, 1, 3, 4, 6, 8, 10, 14, 18 and 24 h respectively after the dogs had been wounded. RESULTS: Positive correlation between SOD and MDA contents was observed in each group. Three hours after injury, MDA level in HHE group began to ascend, reaching the peak level at 6 h that was significantly higher than those in the other 2 groups (P<0.05); SOD level underwent a reverse change, which was significantly lower in HHE group than in the other groups with that in HA group being the highest. Comparable SOD levels in the groups occurred at the time of 14 h, which happened to MDA levels 4 h later. CONCLUSION: Gunshot injuries in the limbs of dogs exposed to hot and humid environment induces increased free oxygen and aggravated the lipid peroxidation, which can be alleviated by heat acclimatization.

Animals↗

PubMed2002

[Relationship between population variation of fig trees and environment in the tropical rainforests of Xishuangbanna].

The species diversity of the plant plays an important role in the ecological environment conservation. In the tropical rainforest of Xishuangbanna the biological diversity is extremely rich, and which is a key region used to biological diversity research. And the fig is a key plant species in the tropical rainforest. The research results about the relationship between the variation of the figs population and environment of the region were following: 1. There were 69 species, variants and subspecies Ficus plant that was known in the tropical rainforest of Xishuangbanna, thereinto there were 23 species and subspecies owned to the Urostigma, and the Pharmacosyea had four species; the Sycomorrus two species and subspecies; while the Ficus owned 41 species, subspecies and variants, then Xishuangbanna borne the most richness and diversity of fig species and numbers in China. 2. The distribution of the figs had intimate connection with the environment, and the species and the quantities showed the most richness in the tropical primary rainforest that was protected well and almost intact, where the figs were mainly to be arbors and giant arbors; and in the devastated stand and secondary forest dwarf arbors, shrubs, bushes and ligneous liana possessed the most in the fig species; while in such regions of tropical rainforest environment that have been destroyed seriously one proportion of the pioneer species of the figs were the main members. 3. Only the key colony of Ficus can be conserved in the tropical rainforest, can the whole ecological environment of the tropical rainforest be protected and rehabilitated, which was one of the important measures to realize it.

Ecology↗

PubMed2002

[Examination of living environment upon return to home for patients with cervical spinal cord injury--report of a case].

Living environment is a problem for spinal cord injury patients upon their return to the society. There are also many instances of home care problems after hospital discharge. For cervical spinal cord injury patients in particular, appropriate intervention/assistance provided by the authorities in accordance with the level of residual function is essential, but there have been few reports on this issue. Here we report on a municipal facility for cervical spinal cord injury patients where a patient moved into upon hospital discharge that did not provide a suitable environment, and the burden posed on his family increased. The patient was a 55-year-old man with traumatic cervical spinal cord injury who was commuting to our rehabilitation center after hospital discharge. We investigated the environment in the municipal housing facility he had moved into, and examined the relationship between the level of cervical spinal cord injury function and ADL assessment before and after hospital discharge. The main problems were an increase in care provided by his wife due to unsuitable toilet facilities and insufficient public facilities concerning the living environment. In terms of ADL by FIM (functional independence measure), namely, toilet transfer, toilet motion and defecation control which he had performed independently at the time of hospital discharge, all had decreased to a level requiring assistance after he moved into the present apartment. Therefore, approach via welfare equipment compensation were undertaken. As a result, the burden for his wife diminished, but the ADL and FIM scores obtained were low. Thus, the living environment facilities for patients with cervical spinal cord injuries should be in accordance with the level of function and ADL, suggesting the necessity for the authorities to establish a cooperative system for running home facilities.

Activities of Daily Living↗

PubMed2003

The impact of genes and pre- and postnatal environment on the metabolic syndrome. Evidence from twin studies.

Our population-based Danish twin study demonstrated a genetic influence on several of the components included in the metabolic syndrome, i.e. glucose intolerance, overall obesity, systolic and diastolic blood pressure and low levels of HDL-cholesterol. Abdominal obesity, insulin resistance and hypertriglyceridaemia had, on the other hand, a relatively higher environmental aetiological component. Furthermore we demonstrated a difference in aetiology among male and female twins indicating an influence of sex on several of the components in the metabolic syndrome. Studies have demonstrated an impact of the intrauterine environment (i.e. low birth weight) for the development of the components in the metabolic syndrome. The validity of conclusions drawn from classical twin studies has therefore been questioned due to the different prenatal circumstances characterising monozygotic (MZ) and dizygotic (DZ) pregnancies. Due to a potentially more adverse intrauterine environment among MZ compared to DZ twins, MZ twins may be more prone to develop various metabolic abnormalities. Our findings of a higher glucose and insulin profiles after oral glucose ingestion, and recently lower insulin-stimulated glucose uptake--indicating glucose intolerance and insulin resistance--together with higher levels of total-cholesterol and triglycerides among MZ compared to DZ twins demonstrate an effect of zygosity (i.e. intrauterine environment) on these metabolic variables and therefore question the assumption of equal pre- and postnatal environment in MZ and DZ twins. Our studies provide further evidence for a prenatal component in the aetiology of the components included in the syndrome and question the validity of classical twin studies on phenotypes with a known prenatal aetiological component. However, our present knowledge is currently far too insufficient to discard the results from classical twin studies concerning the relative role of genes versus environment for the development of the metabolic and haemodynamic components included in the metabolic syndrome.

Diseases in Twins↗