32 resultados para Genotype-environment interactions


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This study reports on children’s observed responses to natural features introduced in the redevelopment of a childcare centre garden. Using an action research approach, the redevelopment was based on the preferences of the director, staff and 18 three- to four-year-olds, as expressed through interviews, conversations, photographs and drawings. Adults and children overwhelmingly preferred natural elements. The kindergarten teacher and assistant observed children’s responses to the implementation of features including a teepee, mulch, greenery, flowers, and loose organic materials. In follow-up interviews, they reported positive child responses including: richer imaginative play; increased physical activity; calmer, more focused play; and positive social interactions. These findings provide further evidence of the importance of providing children with naturalized outdoor play spaces.

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1. Habitat heterogeneity and predator behaviour can strongly affect predator–prey interactions but these factors are rarely considered simultaneously, especially when systems encompass multiple predators and prey.

2. In the Arctic, greater snow geese Anser caerulescens atlanticus L. nest in two structurally different habitats: wetlands that form intricate networks of water channels, and mesic tundra where such obstacles are absent. In this heterogeneous environment, goose eggs are exposed to two types of predators: the arctic fox Vulpes lagopus L. and a diversity of avian predators. We hypothesized that, contrary to birds, the hunting ability of foxes would be impaired by the structurally complex wetland habitat, resulting in a lower predation risk for goose eggs.

3. In addition, lemmings, the main prey of foxes, show strong population cycles. We thus further examined how their fluctuations influenced the interaction between habitat heterogeneity and fox predation on goose eggs.

4. An experimental approach with artificial nests suggested that foxes were faster than avian predators to find unattended goose nests in mesic tundra whereas the reverse was true in wetlands. Foxes spent 3·5 times more time between consecutive attacks on real goose nests in wetlands than in mesic tundra. Their attacks on goose nests were also half as successful in wetlands than in mesic tundra whereas no difference was found for avian predators.

5. Nesting success in wetlands (65%) was higher than in mesic tundra (56%) but the difference between habitats increased during lemming crashes (15%) compared to other phases of the cycle (5%). Nests located at the edge of wetland patches were also less successful than central ones, suggesting a gradient in accessibility of goose nests in wetlands for foxes.

6. Our study shows that the structural complexity of wetlands decreases predation risk from foxes but not avian predators in arctic-nesting birds. Our results also demonstrate that cyclic lemming populations indirectly alter the spatial distribution of productive nests due to a complex interaction between habitat structure, prey-switching and foraging success of foxes.

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This thesis aimed to exploit the Cape fur seal as an alternative model to study mammary gland development and especially the switch from lactation to involution, as well as better understand cell-matrix interactions in vitro, essential to understanding tissue homeostasis and pathogenesis.

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Travellers undertake a process of reorientation and realignment that is particular to each destination. This process intensifies when travelling long distances across borders, cultures and climates, as travellers utilise performative, embodied and creative methods that respond to each new environment. Certain destinations, such as those with unique and extreme natural environments, induce a socio-cultural imaginary that primes travellers for what kind of experience they might have. Large, immersive landscapes and climates congeal with expectations of what each destination requires in order to navigate through it. Common bearings of distance and scale are skewed, as travellers are positioned within areas of vastness. In these moments immersive experiences contrast with daily processes, such as the act of packing a bag, as this heightened sensory awareness exacerbates the subtle material and spatial negotiations. Utilising interviews and photographic documentation of travellers to Iceland and Nepal, this paper develops the proposal that certain destinations intensify our attunement to these moments of reorientation, facilitating situated and creative methods.

As recent developments in the fields of mobilities and tourism draws attention to material interactions during travel, and current ‘new materialism’ movements in theory and practice reveal alternative affective methods of engagement, an exploration of interactions with/in immersive sites is needed in order to evaluate the potential that these kinds of transitions offer everyday experiences of movement. Nigel Thrift’s proposition of Non-Representational Theory provides clarity on the ways in which spatial awareness influences such transitions and environmental experiences. Using his acknowledgement of a more ontologically driven responsiveness to space, this permits a shift away from the presupposed containment of spaces as isolated destinations, toward a relational spatiality that encompasses all actors – including environments – as vital elements in the generative processes of situating our movements.

Creative strategies that afford sensory, aesthetic and embodied performances provide ways to examine these experiences, providing a multitude of possibilities as individual experiences shift towards collective and collaborative performances, as we are immersed within a range of human and non-human actors. This paper explores the transition away from ‘consuming’ environments, and advocates for the need to turn towards a situated collaboration with environments, propelling an awareness of sustainable and creative travel practices. An understanding of affirmative differences is required within travel cultures, rather than expressing transitions as confined within the ‘home’ versus ‘away’ dichotomy that lingers from elite western travel narratives. In order to undertake the many movements required, this paper draws on the theoretical approaches of sustainable nomadism as described by Rosi Braidotti to highlight the linkages of environmental and bodily experiences.

Through multidisciplinary literature, interviews and personal reflections, this paper proposes that certain destinations amplify processes of alignment with the environment, developing affective, embodied and situated experiences that overcome the human/non-human divide.

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This study aimed to determine whether associations between the perceived environment and physical activity are moderated by urban-rural status among midolder aged adults. Environmental (safety, aesthetics, physical activity environment) and physical activity (total, leisure, transport) data from 3,888 adults (55 to 65 years) from urban and rural areas of Victoria, Australia, were analyzed. Multinomial logistic regression examined interactions between urban-rural status and environments in associations with physical activity. Significant (P < .05) interactions were evident and indicated positive associations only among older rural adults for both safety and aesthetics with total and transport physical activity (e.g., rural adults reporting higher safety were 91% to 118% more likely to have higher activity than rural adults reporting low safety). In contrast, the physical activity environment was positively associated with leisure activity among only urban adults. Findings suggest that some tailoring of physical activity promotion strategies targeting the environment may be required for urban and rural midolder aged adults.

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Nursing is characterised as a profession that provides holistic, person-centred care. Due to the condition of the critically ill, a family-centred care model is more applicable in this context. Furthermore, families are at risk of emotional and psychological distress, as a result of the admission of their relative to intensive care. The families' experiences of their interactions in intensive care have the potential to enhance or minimise this risk. This paper presents a subset of findings from a broader study exploring families of critically ill patients' experiences of their interactions with staff, their environment, the patient and other families, when their relative is admitted to an Australian intensive care unit. By developing an understanding of their experience, nurses are able to implement interventions to minimise the families' distress, while providing more holistic, person- and family-centred care.

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In service-oriented computing applications, trust management systems are emerging as a promising technology to improve the e-commerce consumers and provider's relationship. Both consumers and providers need to evaluate the trust levels of potential partners before engaging in interactions. The accuracy of trust evaluation greatly affects the success rate of the interaction. This paper addresses the threats and challenges that can compromise the reliability of the current trust management system. This paper studies and examines the importance of the trust factors of the trust management framework, specifically in dealing with malicious feedback ratings from e-commerce users. To improve the reliability of the trust management systems, an approach that addresses feedback-related vulnerabilities is paramount. A multilevel trust management system computes trust by combining different types of information. Using this combination, we introduce a multilevel framework for a new interactive trust management to improve the correctness in estimate of trust information.

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Understanding what constitutes high quality habitat is crucial for the conservation of species, especially those threatened with extinction. Habitat quality frequently is inferred by comparing the attributes of sites where a species is present with those where it is absent. However, species presence may not always indicate high quality habitat. Demographic parameters are likely to provide a more biologically relevant measure of quality, including a species' ability to successfully reproduce. We examined factors believed to influence territory quality for the grey-crowned babbler (Pomatostomus temporalis), a cooperatively breeding woodland bird that has experienced major range contraction and population decline in south-eastern Australia. Across three broad regions, we identified active territories and determined the presence of fledglings and the size of family groups, as surrogates of territory quality. These measures were modelled in relation to habitat attributes within territories, the extent of surrounding wooded vegetation, isolation from neighbouring groups, and the size of the neighbourhood population. Fledgling presence was strongly positively associated with group size, indicating that helpers enhance breeding success. Surprisingly, no other territory or landscape-scale variables predicted territory quality, as inferred from either breeding success or group size. Relationships between group size and environmental variables may be obscured by longer-term dynamics in group size. Variation in biotic interactions, notably competition from the noisy miner (Manorina melanocephala), also may contribute. Conservation actions that enhance the number and size of family groups will contribute towards reversing declines of this species. Despite associated challenges, demographic studies have potential to identify mechanistic processes that underpin population performance; critical knowledge for effective conservation management.

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BACKGROUND: Dementia residential facilities can be described as traditional or non-traditional facilities. Non-traditional facilities aim to utilise principles of environmental design to create a milieu that supports persons experiencing cognitive decline. This study aimed to compare these two environments in rural Australia, and their influence on residents' occupational engagement. METHODS: The Residential Environment Impact Survey (REIS) was used and consists of: a walk-through of the facility; activity observation; interviews with residents and employees. Thirteen residents were observed and four employees interviewed. Resident interviews did not occur given the population diagnosis of moderate to severe dementia. Descriptive data from the walk-through and activity observation were analysed for potential opportunities of occupational engagement. Interviews were thematically analysed to discern perception of occupational engagement of residents within their facility. RESULTS: Both facilities provided opportunities for occupational engagement. However, the non-traditional facility provided additional opportunities through employee interactions and features of the physical environment. Interviews revealed six themes: Comfortable environment; roles and responsibilities; getting to know the resident; more stimulation can elicit increased engagement; the home-like experience and environmental layout. These themes coupled with the features of the environment provided insight into the complexity of occupational engagement within this population. CONCLUSION: This study emphasises the influence of the physical and social environment on occupational engagement opportunities. A non-traditional dementia facility maximises these opportunities and can support development of best-practice guidelines within this population.

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Many parts of the world in which common infectious diseases are endemic also have the highest prevalence of trace metal deficiencies or rising rates of trace metal pollution. Infectious diseases can increase human susceptibility to adverse effects of metal exposure (at suboptimal or toxic levels), and metal excess or deficiency can increase the incidence or severity of infectious diseases. The co-clustering of major infectious diseases with trace metal deficiency or toxicity has created a complex web of interactions with serious but poorly understood health repercussions, yet has been largely overlooked in animal and human studies. This book focuses on the distribution, trafficking, fate, and effects of trace metals in biological systems. Its goal is to enhance our understanding of the relationships between homeostatic mechanisms of trace metals and the pathogenesis of infectious diseases. Drawing on expertise from a range of fields, the book offers a comprehensive review of current knowledge on vertebrate metal-withholding mechanisms and the strategies employed by different microbes to avoid starvation (or poisoning). Chapters summarize current, state-of-the-art techniques for investigating pathogen-metal interactions and highlight open question to guide future research. The book makes clear that improving knowledge in this area will be instrumental to the development of novel therapeutic measures against infectious diseases. ContributorsM. Leigh Ackland, Vahid Fa Andisi, Angele L. Arrieta, Michael A. Bachman, J. Sabine Becker, Robert E. Black, Julia Bornhorst, Sascha Brunke, Joseph A. Caruso, Jennifer S. Cavet, Anson C. K. Chan, Christopher H. Contag, Heran Darwin, George V. Dedoussis, Rodney R. Dietert, Victor J. DiRita, Carol A. Fierke, Tamara Garcia-Barrera, David P. Giedroc, Peter-Leon Hagedoorn, James A. Imlay, Marek J. Kobylarz, Joseph Lemire, Wenwen Liu, Slade A. Loutet, Wolfgang Maret, Andreas Matusch, Trevor F. Moraes, Michael E. P. Murphy, Maribel Navarro, Jerome O. Nriagu, Ana-Maria Oros-Peusquens, Elisabeth G. Pacyna, Jozef M. Pacyna, Robert D. Perry, John M. Pettifor, Stephanie Pfaffen, Dieter Rehder, Lothar Rink, Anthony B. Schryvers, Ellen K. Silbergeld, Eric P. Skaar, Miguel C. P. Soares, Kyrre Sundseth, Dennis J. Thiele, Richard B. Thompson, Meghan M. Verstraete, Gonzalo Visbal, Fudi Wang, Mian Wang, Thomas J. Webster, Jeffrey N. Weiser, Günter Weiss, Inga Wessels, Bin Ye, Judith T. Zelikoff, Lihong Zhang

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BACKGROUND: The apolipoprotein E (APOE) risk allele (ɛ4) is associated with higher total cholesterol (TC), amplified response to saturated fatty acid (SFA) reduction, and increased cardiovascular disease. Although knowledge of gene risk may enhance dietary change, it is unclear whether ɛ4 carriers would benefit from gene-based personalized nutrition (PN). OBJECTIVES: The aims of this study were to 1) investigate interactions between APOE genotype and habitual dietary fat intake and modulations of fat intake on metabolic outcomes; 2) determine whether gene-based PN results in greater dietary change than do standard dietary advice (level 0) and nongene-based PN (levels 1-2); and 3) assess the impact of knowledge of APOE risk (risk: E4+, nonrisk: E4-) on dietary change after gene-based PN (level 3). DESIGN: Individuals (n = 1466) recruited into the Food4Me pan-European PN dietary intervention study were randomly assigned to 4 treatment arms and genotyped for APOE (rs429358 and rs7412). Diet and dried blood spot TC and ω-3 (n-3) index were determined at baseline and after a 6-mo intervention. Data were analyzed with the use of adjusted general linear models. RESULTS: Significantly higher TC concentrations were observed in E4+ participants than in E4- (P < 0.05). Although there were no significant differences in APOE response to gene-based PN (E4+ compared with E4-), both groups had a greater reduction in SFA (percentage of total energy) intake than at level 0 (mean ± SD: E4+, -0.72% ± 0.35% compared with -1.95% ± 0.45%, P = 0.035; E4-, -0.31% ± 0.20% compared with -1.68% ± 0.35%, P = 0.029). Gene-based PN was associated with a smaller reduction in SFA intake than in nongene-based PN (level 2) for E4- participants (-1.68% ± 0.35% compared with -2.56% ± 0.27%, P = 0.025). CONCLUSIONS: The APOE ɛ4 allele was associated with higher TC. Although gene-based PN targeted to APOE was more effective in reducing SFA intake than standard dietary advice, there was no difference between APOE "risk" and "nonrisk" groups. Furthermore, disclosure of APOE nonrisk may have weakened dietary response to PN. This trial was registered at clinicaltrials.gov as NCT01530139.

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The appearance of animal colour signals depends jointly upon the ambient light spectrum and the signal's reflectance spectra. Light environment heterogeneity might, therefore, allow individuals to enhance their signal by signalling in an environment that increases signal efficacy. We tested this hypothesis by providing male guppies (Poecilia reticulata), a choice of three light environments in which to display their colour signal to females: green, lilac, and clear. We paired males with both receptive and non-receptive females to test whether female response might affect male behavioural decisions. Males preferred the clear environment in all trials and this environment also resulted in males having the highest average visual contrast. Sexual behaviour was influenced by complex interactions between female receptivity, light environment, and male colour pattern contrast. Males spent significantly more time in the environment in which their colour signal had the highest contrast, but only when paired with receptive females. Significant interactions between light environment and individual male colour components were also seen only in receptive trials. Our results suggest that males use light environment to enhance their colour pattern, but only in the presence of receptive females.

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Identified and characterized microbial nanowires in three different cyanobacteria and studied their potential role in cell-metalloid/metal interactions

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Microbial nanowires (MNWs) can play an important role in the transformation and mobility of toxic metals/metalloids in environment. The potential role of MNWs in cell-arsenic (As) interactions has not been reported in microorganisms and thus we explored this interaction using Synechocystis PCC 6803 as a model system. The effect of half maximal inhibitory concentration (IC50) [~300 mM As (V) and ~4 mM As (III)] and non-inhibitory [4X lower than IC50, i.e., 75 mM As (V) and 1 mM As (III)] of As was studied on Synechocystis cells in relation to its effect on Chlorophyll (Chl) a, type IV pili (TFP)-As interaction and intracellular/extracellular presence of As. In silico analysis showed that subunit PilA1 of electrically conductive TFP, i.e., microbial nanowires of Synechocystis have putative binding sites for As. In agreement with in silico analysis, transmission electron microscopy analysis showed that As was deposited on Synechocystis nanowires at all tested concentrations. The potential of Synechocystis nanowires to immobilize As can be further enhanced and evaluated on a large scale and thus can be applied for bioremediation studies.