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Influence of novel versus home environments on sensitization to the psychomotor stimulant effects of cocaine and amphetamine.

The acute psychomotor response (rotational behavior in rats with a unilateral 6-OHDA lesion), and the development of sensitization, were studied in rats that received seven consecutive daily injections of amphetamine (Experiment 1) or cocaine (Experiment 2) either at home or in a 'novel' test environment. The home (HOME) and novel (NOVEL) cages were physically identical, but one group lived and was tested in these cages, whereas the rats in the other group were transported from the stainless steel hanging cages where they lived, to those NOVEl test cages, for each test session. In Exp. 1, the acute psychomotor response to 3.0 mg/kg of amphetamine i.p. and the development of sensitization (increase in the rotational response between the first and the the seventh test session) were greater in the NOVEL than in the HOME environment. In Expt. 2, there were no significant group differences in the acute response to 20 mg/kg of cocaine i.p., but the animals tested in the NOVEL environment showed greater sensitization than animals tested in the HOME environment. In addition, the animals pretreated with cocaine in the NOVEL environment, but not those pretreated with cocaine in the HOME environment, showed conditioned rotational behavior in response to an injection of saline. These data indicate that: (i) sensitization to the psychomotor activating effects of both amphetamine and cocaine is enhanced in a NOVEL environment; (ii) this phenomenon appears to the independent of the effects of the NOVEL environment on the acute response to these drugs; (iii) a robust conditioned psychomotor response to contextual cues develops only when cocaine treatments are given in the NOVEL test environment.

Amphetamine↗

Gonadal hormones during puberty organize environment-related social interaction in the male rat.

This study examined the role of gonadal androgens during puberty on the development of environment-related social interaction (SI) in male rats. SI in an unfamiliar environment versus SI in a familiar environment was evaluated in young adult rats as a function of sex and gonadal status. Intact male rats at 60 days of age exhibited a differential response to the two environments, whereas SI in intact female rats at 60 days was equivalent in the two environments. Furthermore, male rats castrated as juveniles and tested for SI at 60 days displayed a pattern of environment-related SI similar to SI in intact adult female rats. This effect of juvenile castration on SI in male rats was prevented by chronic exposure to testosterone propionate (TP) over Days 30 through 60. SI in male rats castrated in adulthood, on the other hand, was not altered either 2 or 4 weeks postcastration. The results from this study indicate that pubertal secretions of gonadal androgen(s) are necessary for the development of environment-related SI in male rats. In contrast, secretions of gonadal androgens in adulthood do not appear to be critical for the continued expression of environment-related SI, as suggested by the observation that environment-related SI in male rats remains unchanged by castration in adulthood.

Animals↗

Impacts of QTL x environment interactions on genetic response to marker-assisted selection.

Genotype x environment (GE) interaction is a common characteristic for quantitative traits, and has been a subject of great concern for breeding programs. Simulation studies were conducted to investigate the effects of GE interaction on genetic response to marker-assisted selection (MAS). In our study we demonstrated that MAS is generally more efficient than phenotypic selection in the presence of GE interaction, and this trend is more pronounced for developing broadly adaptable varieties. The utilization of different QTL information dramatically influences MAS efficiency. When MAS is based on QTLs evaluated in a single environment, the causal QTL x environment (QE) interactions usually reduce general response across environments, and the reduction in the cumulative general response is a function of the proportion of QE interactions for the trait studied. However, MAS using QTL information evaluated in multiple environments not only yields higher general response, but the general response obtained is also reasonably robust to QE interactions. The total response achieved by MAS in a specific environment depends largely on the total heritability of traits and is slightly subject to relative changes between general heritability and GE interaction heritability. Two breeding strategies, breeding experiments conducted in one environment throughout and in two environments alternately, were also examined for the implementation of marker-based selection. It was thus concluded that plant breeders should be cautious to utilize QTL information from only one environment and execute breeding studies in another.

Breeding↗

Determination of the environmental sensitivity of selection lines by the selection environment.

The parents chosen to continue 10 independent selection lines of Schizophyllum commune over eight successive generations of selection, along with unselected controls, have been retrospectively examined for their response to growth at 15 degrees, 20 degrees, 25 degrees, 30 degrees and 35 degrees C. The regression of rate of growth on temperature was essentially linear over the range 15 degrees to 30 degrees C for all lines in all generations as was also the regression of rate of growth on various biological assessments of the environments over the whole temperature range. Either regression, therefore, provided linear regression coefficients which adequately accounted for the relative sensitivities of the lines to temperature in each generation of selection. These measures of environmental sensitivity confirmed our earlier report that selection for high mean performance in a good environment or for low mean performance in a poor environment leads to selections that are more sensitive to environmental variation than selections for high mean performance in a poor environment or for low mean performance in a good environment. These differences in sensitivity emerge as correlated responses during selection and the magnitude of these correlated responses is higher in the good environment than in the poor environment irrespective of the direction of selection. The environmental sensitivity of selection lines can be modified in either direction as required by either selecting for sensitivity simultaneously with the selection for mean performance or by selecting for mean performance in an above or below average environment. The quality of environments in which artificial selection is usually carried out is likely to have led to high selections with maximum environmental sensitivity and low selections with minimum sensitivity.

Environment↗

A dynamic study of genotype-environment interaction with egg laying of Tribolium castaneum.

Within-line family selection was carried out at an optimum (33 degrees C) and two stress temperatures (28 degrees C and 38 degrees C) for increasing egg number laid by virgin females of Tribolium castaneum from the 7th to the 11th day after adult emergence. A control was maintained throughout the experiment. Two replicated lines were selected at each temperature and all selected lines were tested in each of the three environments. Direct and correlated responses to selection in different environments have been analysed in order to study implications of genotype-environment interaction on the selection outcome. Although selection at the optimum environment has been the most effective it did not confer the specialisation needed for performance in stress environments. However, selecting in adverse environments led to a broader range of performance over environments, which in one case (38 degrees C) included the optimum one. The degree of adaptation to adverse environments was mainly determined by the magnitude of the genetic correlation between performances in the adverse and the optimum environments. The evolution of such correlations through selection has also been investigated.

Adaptation, Physiological↗

Enriched environment enhances recovery of motor function after focal ischemia in mice, and downregulates the transcription factor NGFI-A.

The purpose of this study was to investigate the effect of enriched environment on motor function after experimental stroke in mice, and to determine whether time in enriched environment affects functional recovery. Earlier investigations have shown that rats placed in an enriched environment after focal ischemia, remarkably improve motor function, but similar observations in mice have not been reported. In this study, we show that placing mice in an enriched environment for 3 h daily for 2 weeks, after transient (50 mins) occlusion of the middle cerebral artery, enhanced neurologic outcome. Continuous postischemic housing in the enriched environment likewise improved motor function, but mortality increased. Two weeks exposure to enriched environment followed by housing the mice in standard cages for 2 weeks, resulted in a loss of the improved motor function. In contrast, 4 weeks exposure to enriched environment led to an improved motor function and to a better maintenance of neurologic recovery. The expression levels of the immediate-early gene nerve growth factor-induced gene A at 2 to 3 weeks of recovery decreased in animals housed in enriched environment, implying this transcription factor in the recovery process. We conclude that housing mice in an enriched environment after experimental stroke improves functional outcome. Also, the presented experimental procedure is useful for further studies of the genomics of functional recovery after experimental stroke.

Animals↗

The skin barrier state of aged hairless mice in a dry environment.

BACKGROUND: Many elderly people have chronic xerosis, and frequently experience an exacerbation during winter. OBJECTIVES: To investigate the barrier state of aged murine skin with or without barrier disruption in a dry environment. METHODS: Aged and young hairless mice were kept separately in dry and normal conditions for 9 days. Acetone treatment was used to perturb the skin barrier. Skin barrier function was measured as transepidermal water loss (TEWL), and morphological changes in the epidermis were studied by electron microscopy. RESULTS: The baseline TEWL was not higher in the dry environment. The number of stratum corneum (SC) layers and the epidermal thickness of aged mice increased in the dry environment. The recovery rate of the aged skin barrier was neither accelerated nor delayed in the dry environment. In the normal environment, aged mice recovered more slowly than young mice. After barrier perturbation in the aged mice, changes in SC layers and in epidermal thickness were similar in the two environments. The secretion and number of lamellar bodies did not differ between the two environments. CONCLUSIONS: We confirmed that a dry environment induces epidermal proliferation and scaling in both aged and young mice. However, no remarkable difference was found in the skin barrier recovery of aged hairless mice in a dry environment.

Acetone↗

The evolution of phenotypic plasticity in spatially structured environments: implications of intraspecific competition, plasticity costs and environmental characteristics.

We model the evolution of reaction norms focusing on three aspects: frequency-dependent selection arising from resource competition, maintenance and production costs of phenotypic plasticity, and three characteristics of environmental heterogeneity (frequency of environments, their intrinsic carrying capacity and the sensitivity to phenotypic maladaptation in these environments). We show that (i) reaction norms evolve so as to trade adaptation for acquiring resources against cost avoidance; (ii) maintenance costs cause reaction norms to better adapt to frequent rather than to infrequent environments, whereas production costs do not; and (iii) evolved reaction norms confer better adaptation to environments with low rather than with high intrinsic carrying capacity. The two previous findings contradict earlier theoretical results and originate from two previously unexplored features that are included in our model. First, production costs of phenotypic plasticity are only incurred when a given phenotype is actually produced. Therefore, they are proportional to the frequency of environments, and these frequencies thus affect the selection pressure to avoid costs just as much as the selection pressure to improve adaptation. This prevents the frequency of environments from affecting the evolving reaction norm. Secondly, our model describes the evolution of plasticity for a phenotype determining an individual's capability to acquire resources, and thus its realized carrying capacity. When individuals are distributed randomly across environments, they cannot avoid experiencing environments with intrinsically low carrying capacity. As selection pressures arising from the need to improve adaptation are stronger under such extreme conditions than under mild ones, better adaptation to environments with low rather than with high intrinsic carrying capacity results.

Adaptation, Physiological↗

Concepts guiding the study of the impact of the built environment on physical activity for older adults: a review of the literature.

OBJECTIVE: To identify theoretical models and key concepts used to predict the association between built environment and seniors' physical activity on the basis of a comprehensive review of the published literature. DATA SOURCE: Computer searches of Medline (1966-2002), PubMed (1966-2002), and Academic Search Elite (1966-2002) were conducted, and 27 English-language articles were found. Search terms included built environment, physical activity, exercise, walking, neighborhood, urban design, seniors, aging, aging in place, and physical environment. STUDY INCLUSION AND EXCLUSION CRITERIA: The primary inclusion criterion included the relation between the built environment and the physical activity among seniors living in neighborhoods. Studies assessing physical activity or overall health of a community-based population were included if underlying theoretical models and concepts were applicable to a senior population. Studies solely assessing social or psychosocial characteristics of place were excluded, as were review articles. DATA EXTRACTION: Extracted data included theoretical model, aspect of built environment studied, methods, and outcomes. DATA SYNTHESIS: Tables present key definitions and summarize information from empirical studies. RESULTS: Twenty-seven articles that focused on the environment-behavior relation in neighborhoods, six specific to seniors, were found. This area of research is in its infancy, and inconsistent findings reflect difficulties in measurement of the built environment. CONCLUSIONS: The relation between the built environment and the physical activity among seniors has been the subject of a limited number of studies. The choice of theoretical model drives the selection of concepts and variables considered. Safety, microscale urban design elements, aesthetics, and convenience of facilities are consistently studied across models. Few validated instruments have been developed and tested to measure neighborhood built environment.

Aged↗

Virtual environments in brain damage rehabilitation: a rationale from basic neuroscience.

The potential of virtual environments in assessment and training of cognitive function is a more than adequate reason for their application to neurorehabilitation. However, there is a more fundamental justification, and one which is firmly rooted in the neuroscience literature. Over the last half century there has been a wealth of published evidence that enriching the environments of laboratory rats stimulates neuroplastic change in the cerebral cortex, enhances learning and problem solving in normal rats and reduces cognitive impairment in brain damaged rats. Central to all three effects of enrichment are the increased levels of interaction with the physical environment engendered by enrichment. Placing humans who have damaged brains in virtual environments is one way of enhancing their levels of environmental interaction which, because of cognitive impairments and sensory and motor disabilities, is otherwise difficult to achieve. In this chapter we explore the potential of virtual environments as enriched environments within the rehabilitation regime. The underlying assumption, that interaction with a virtual environment is functionally equivalent to interaction with a real environment, is examined. Three lines of relevant evidence are reviewed, neuroimaging studies and psychophysiological studies of people in virtual environments and studies of transfer of training from virtual to real tasks. An agenda for future research in this are is proposed.

Animals↗

Veterinary medicines in the environment.

The impact of veterinary medicines on the environment will depend on a number of factors including physicochemical properties, amount used and method of administration, treatment type and dose, animal husbandry practices, manure storage and handling practices, metabolism within the animal, and degradation rates in manure and slurry. Once released to the environment, other factors such as soil type, climate, and ecotoxicity also determine the environmental impact of the compound. The importance of individual routes into the environment for different types of veterinary medicines varies according to the type of treatment and livestock category. Treatments used in aquaculture have a high potential to reach the aquatic environment. The main routes of entry to the terrestrial environment are from the use of veterinary medicines in intensively reared livestock, via the application of slurry and manure to land, and by the use of veterinary medicines in pasture-reared animals where pharmaceutical residues are excreted directly into the environment. Veterinary medicines applied to land via spreading of slurry may also enter the aquatic environment indirectly via surface runoff or leaching to groundwater. It is likely that topical treatments have greater potential to be released to the environment than treatments administered orally or by injection. Inputs from the manufacturing process, companion animal treatments, and disposal are likely to be minimal in comparison. Monitoring studies demonstrate that veterinary medicines do enter the environment, with sheep dip chemicals, antibiotics, sealice treatments, and anthelmintics being measured in soils, groundwater, surface waters, sediment, or biota. Maximum concentrations vary across chemical classes, with very high concentrations being reported for the sheep dip chemicals. The degree to which veterinary medicines may adsorb to particulates varies widely. Partition coefficients (K(d)) range from low (0.61 L kg(-1)) to high (6000 L kg(-1)). The variation in partitioning for many of the compounds in different soils was significant (up to a factor of 30), but these differences could be not be explained by normalization to the organic carbon content of the soils. Thus, to arrive at a realistic assessment of the availability of veterinary medicines for transport through the soil and uptake into soil organisms, the K(oc) (which is used in many of the exposure models) may not be an appropriate measure. Transport of particle-associated substances from soil to surface waters has also been demonstrated. Veterinary medicines can persist in soils for days to years, and half-lives are influenced by a range of factors including temperature, pH, and the presence of manure. The persistence of major groups of veterinary medicines in soil, manure, slurry, and water varies across and within classes. Ecotoxicity data were available for a wide range of veterinary medicines. The acute and chronic effects of avermectins and sheep dip chemicals on aquatic organisms are well documented, and these substances are known to be toxic to many organisms at low concentrations (ng L(-1) to microg L(-1)). Concerns have also been raised about the possibility of indirect effects of these substances on predatory species (e.g., birds and bats). Data for other groups indicate that toxicity values are generally in the mg L(-1) range. For the antibiotics, toxicity is greater for certain species of algae and marine bacteria. Generally, toxicity values for antibacterial agents were significantly higher than reported environmental concentrations. However, because of a lack of appropriate toxicity data, it is difficult to assess the environmental significance of these observations with regard to subtle long-term effects.

Agriculture↗

Human placental estrogen synthetase (aromatase). Effect of environment on the kinetics of protein-protein and substrate-protein interactions and the production of 19-oxygenated androgen intermediates in the purified reconstituted cytochrome P450 enzyme system.

Estrogen synthetase (aromatase) catalyzes the conversion of androgen into estrogen via two hydroxylations at C19 and a subsequent C19-10 lyase reaction. We report here the results of a reconstitution study using a highly purified aromatase cytochrome P450 monooxygenase enzyme system, with both protein components (cytochrome P450 and NADPH-cytochrome P450 reductase) obtained from human term placental microsomes. By varying one of the components (amounts of cytochrome P450, NADPH-cytochrome P450 reductase, or androgen substrate) as the other two were held constant in four different environments (phospholipid, non-ionic detergent, mixture of phospholipid and non-ionic detergent and buffer alone), we obtained evidence supporting the following conclusions. The reconstituted enzyme is more active and the protein components exhibit much lower apparent Km values in the detergent and/or lipid environment compared with buffer alone. Although the apparent Km and Vmax values for each aromatase protein component differ significantly in most cases with the particular limiting component and environment, the catalytic efficiency (Kcat/Km) was independent of the limiting protein component and varied with the environment only (highest in the lipid-detergent mixture and lowest in lipid alone). When the concentration of androgen substrate (androstenedione or testosterone) was varied at constant amounts of the aromatase protein components (NADPH-cytochrome P450 reductase saturating), the Km was lower and the Vmax was higher for adrostenedione. The specificity constant (Vmax/Km) was a function of the reconstitution environment (highest in lipid alone and lowest in detergent alone) and was, on average, about 4-fold higher for androstenedione in a particular environment. The extent of production of 19-oxygenated androgen intermediates (19-hydroxy and 19-oxo androstenedione) was examined at three different levels of aromatase cytochrome P450 (subsaturating, saturating, super-saturating) relative to the NADPH-cytochrome P450 reductase component in the three different hydrophobic environments using androstenedione as substrate. Both 19-oxygenated androgens, each made in comparable amounts relative to control, were isolatable in greatest amounts under cytochrome P450 super-saturating conditions in the detergent-lipid mixed environment, and in least amounts under cytochrome P450 subsaturating conditions in the lipid-only environment. Based on these data, we propose that 19-oxygenated androgen intermediates are biosynthesized sequentially in a step-wise fashion as the cytochrome P450 and NADPH-cytochrome P450 reductase form transient complexes, and that the amount of isolatable 19-oxygenated androgen is proportional to the amount of excess cytochrome P450 component.

Androgens↗

Does walking in a virtual environment induce unstable gait? An examination of vertical ground reaction forces.

Virtual reality (VR) can induce postural instability in standing and walking, as quantified with kinematic parameters. This study examines the effect of a VR environment on kinetic gait parameters. Ten healthy volunteers walked on an instrumented treadmill in a VR environment and a non-VR environment. In the VR environment, a corridor with colored vertical stripes comprising the walls was projected onto a concave screen placed in front of the treadmill. The speed of the moving image was perceptually equivalent to the speed of the treadmill, creating an illusion that subjects walked through the corridor. Vertical ground reaction forces were sampled. Kinetic parameters that reflect gait stability (weight acceptance peak force, weight acceptance rate, push-off peak force and push-off rate) were compared between the VR and non-VR environments. Subjects walked in the VR environment with increased magnitudes and rates of weight acceptance force and with increased rates of push-off force. Variability in weight acceptance rates and peak forces, and variability in push-off peak forces, were also increased in the VR environment. The gait deviations reflect a compensatory response to visual stimulation that occurs in the VR environment, suggesting that walking in a VR environment may induce gait instability in healthy subjects.

Adult↗

Circulating leptin response to feeding and exogenous infusion of insulin in sheep exposed to thermoneutral and cold environments.

Leptin has been shown to regulate feed intake and energy expenditure. Insulin stimulates leptin secretion in rodents, but its action on leptin secretion is still obscure in ruminants. If insulin stimulates leptin secretion in ruminants, circulating leptin concentrations may change during exposure to cold, because of fluctuating insulin secretion and action in the cold environment. The present experiment was designed to determine whether feeding or exogenous administration of insulin affects circulating leptin levels in sheep exposed to thermoneutral and cold environments. Suffolk rams that were shorn and fed a diet once daily were subjected to a thermoneutral (20 degrees C) or cold (0 degrees C) environment for at least 1 week. Overall mean concentrations of plasma leptin in the feeding experiment were lower (P<0.05) in the cold environment than in the thermoneutral environment. Plasma leptin levels remained relatively unchanged after feeding in both environments, though plasma insulin response to feeding in both environments increased (P<0.01). The euglycemic clamps (insulin infusion rate: 4 mUkgBW(-1)min(-1) for 2 h) increased (P<0.01) circulating leptin concentrations in the thermoneutral, but not in the cold environment. These results suggest that lower circulating leptin levels in ruminants exposed to the cold environment could be partly due to the depressed insulin action on leptin secretion.

Animals↗

Effects of environment on the creep properties of a poly(ethylmethacrylate) based bone cement.

The effect of test environment on the creep behavior of a poly(ethylmethacrylate) bone cement was investigated. The aim of the study was to assess the influence of environment on the inherent material behavior, and so it was convenient to perform tests in tension on well-prepared samples. In addition to control tests in air, the liquid environments studied were water, Ringer's solution and Intralipid. Creep tests were performed in each of these environments with a range of aging times, test temperatures and applied stresses. In order to compare the effects of the environments, the creep curves were fitted to a generalized form, from which a creep rate was determined. The ratio of these creep rates between different environments at each testing condition was then used as a basis for a comparison of the detailed effects of environment. It was found that in all cases the water-based environments (water and Ringer's) had similar effects and gave the largest creep rates. Intralipid was then intermediate and air gave the lowest creep rates. These effects are mainly due to plasticization by water, although with Intralipid, some increased monomer leaching occurred, which served to reduce the creep rates. The influence of environment on the effects of aging time, temperature and stress were complex, although in general any conditions which increased water plasticization (longer aging, higher temperature and to a lesser extent, higher stress) gave an increase in creep rate. The major exception to this was at temperatures of 40 degrees C and above, where the effects of water plasticization were diminished, due to the inherent increase in molecular mobility of the material.

Journal Article↗

Generation of the alloreactive T-cell repertoire: interaction of T-cell genotype and maturation environment.

The influences of the T-cell genotype and the T-cell maturation environment on generation of the T-cell alloreactive repertoire were evaluated in cytotoxic T-lymphocyte responses to Kb mutant determinants expressed by the strains B6. C-H-2bm1 and B6-H2-bm6. By constructing bone marrow chimeras using either H-2b of H-2d mice as the source of donor cells and either H-2d or H-2b irradiated mice as recipients, it was first determined whether the T-cell major histocompatibility complex genotype alone determines the alloreactive repertoire. The results of such experiments indicated that H-2b T cells that have matured in a normal H-2b environment (C57BL/6N, C57BL/10Sn) or H-2d T cells that have matured in a chimeric H-2b environment (B10.D2 leads to C57BL/10Sn) are responsive to Kbm1 and Kbm6 determinants while H-2b T cells that have matured in an H-2d chimeric environment (C57BL/10Sn leads to B10.D2) have a diminished responsiveness to H-2bm1 and are completely unresponsive to H-2bm6. These findings showed that T-cell genotype alone does not determine the alloreactive repertoire to mutant Kbm1 and Kbm6 determinants and suggested that the T-cell maturation environment plays a critical role in this process. Further studies were carried out to determine whether the T-cell maturation environment alone determines this repertoire, such that maturation in an H-2b but not in an H-2d environment is both necessary and sufficient to generate reactivity to Kbm6. Experiments in which either H-2d responder populations neonatally made tolerant to H-2b or unlabeled target blocking of normal H-2d responders were used provided evidence that T cells specific for Kbm6 mutant determinants are present in the repertoire of H-2d T cells that have matured in an H-2d environment. These findings suggest that the alloreactive T-cell repertoire is not determined by the T-cell major histocompatibility complex genotype alone or by the T-cell maturation environment alone but rather than it is the product of unique interactions between the two.

Animals↗

A virtual therapeutic environment with user projective agents.

Today, we see the Internet as more than just an information infrastructure, but a socializing place and a safe outlet of inner feelings. Many personalities develop aside from real world life due to its anonymous environment. Virtual world interactions are bringing about new psychological illnesses ranging from netaddiction to technostress, as well as online personality disorders and conflicts in multiple identities that exist in the virtual world. Presently, there are no standard therapy models for the virtual environment. There are very few therapeutic environments, or tools especially made for virtual therapeutic environments. The goal of our research is to provide the therapy model and middleware tools for psychologists to use in virtual therapeutic environments. We propose the Cyber Therapy Model, and Projective Agents, a tool used in the therapeutic environment. To evaluate the effectiveness of the tool, we created a prototype system, called the Virtual Group Counseling System, which is a therapeutic environment that allows the user to participate in group counseling through the eyes of their Projective Agent. Projective Agents inherit the user's personality traits. During the virtual group counseling, the user's Projective Agent interacts and collaborates to recover and increase their psychological growth. The prototype system provides a simulation environment where psychologists can adjust the parameters and customize their own simulation environment. The model and tool is a first attempt toward simulating online personalities that may exist only online, and provide data for observation.

Behavior, Addictive↗

Analysis of the moral habitability of the nursing work environment.

BACKGROUND: Following health reform, nurses have experienced the tremendous stress of heavy workloads, long hours and difficult professional responsibilities. In recognition of these problems, a study was conducted that examined the impact of the working environment on the health of nurses. After conducting focus groups across Canada with nurses and others well acquainted with nursing issues, it became clear that the difficult work environments described had significant ethical implications. AIM: The aim of this paper is to report the findings of research that examined the moral habitability of the nursing working environment. METHODS: A secondary analysis was conducted using the theoretical work of Margaret Urban Walker. Moral practices and responsibilities from Walker's perspective cannot be extricated from other social roles, practices and divisions of labour. Moral-social orders, such as work environments in this research, must be made transparent to examine their moral habitability. Morally habitable environments are those in which differently situated people experience their responsibilities as intelligible and coherent. They also foster recognition, cooperation and shared benefits. FINDINGS: Four overarching categories were developed through the analysis of the data: (1) oppressive work environments; (2) incoherent moral understandings; (3) moral suffering and (4) moral influence and resistance. The findings clearly indicate that participants perceived the work environment to be morally uninhabitable. The social and spatial positioning of nurses left them vulnerable to being overburdened by and unsure of their responsibilities. Nevertheless, nurses found meaningful ways to resist and to influence the moral environment. CONCLUSIONS: We recommend that nurses develop strong moral identities, make visible the inseparability of their proximity to patients and moral accountability, and further identify what forms of collective action are most effective in improving the moral habitability of their work environments.

Attitude of Health Personnel↗