897 resultados para major epitope on CII


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Recent work suggests that the environment experienced in early life can alter life histories in wild populations [1, 2, 3, 4 and 5], but our understanding of the processes involved remains limited [6 and 7]. Since anthropogenic environmental change is currently having a major impact on wild populations [8], this raises the possibility that life histories may be influenced by human activities that alter environmental conditions in early life. Whether this is the case and the processes involved remain unexplored in wild populations. Using 23 years of longitudinal data on the Mauritius kestrel (Falco punctatus), a tropical forest specialist, we found that females born in territories affected by anthropogenic habitat change shifted investment in reproduction to earlier in life at the expense of late life performance. They also had lower survival rates as young adults. This shift in life history strategy appears to be adaptive, because fitness was comparable to that of other females experiencing less anthropogenic modification in their natal environment. Our results suggest that human activities can leave a legacy on wild birds through natal environmental effects. Whether these legacies have a detrimental effect on populations will depend on life history responses and the extent to which these reduce individual fitness.

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Ancestral human populations had diets containing more indigestible plant material than present-day diets in industrialized countries. One hypothesis for the rise in prevalence of obesity is that physiological mechanisms for controlling appetite evolved to match a diet with plant fiber content higher than that of present-day diets. We investigated how diet affects gut microbiota and colon cells by comparing human microbial communities with those from a primate that has an extreme plant-based diet, namely, the gelada baboon, which is a grazer. The effects of potato (high starch) versus grass (high lignin and cellulose) diets on human-derived versus gelada-derived fecal communities were compared in vitro. We especially focused on the production of short-chain fatty acids, which are hypothesized to be key metabolites influencing appetite regulation pathways. The results confirmed that diet has a major effect on bacterial numbers, short-chain fatty acid production, and the release of hormones involved in appetite suppression. The potato diet yielded greater production of short-chain fatty acids and hormone release than the grass diet, even in the gelada cultures, which we had expected should be better adapted to the grass diet. The strong effects of diet on hormone release could not be explained, however, solely by short-chain fatty acid concentrations. Nuclear magnetic resonance spectroscopy found changes in additional metabolites, including betaine and isoleucine, that might play key roles in inhibiting and stimulating appetite suppression pathways. Our study results indicate that a broader array of metabolites might be involved in triggering gut hormone release in humans than previously thought. IMPORTANCE: One theory for rising levels of obesity in western populations is that the body's mechanisms for controlling appetite evolved to match ancestral diets with more low-energy plant foods. We investigated this idea by comparing the effects of diet on appetite suppression pathways via the use of gut bacterial communities from humans and gelada baboons, which are modern-day primates with an extreme diet of low-energy plant food, namely, grass. We found that diet does play a major role in affecting gut bacteria and the production of a hormone that suppresses appetite but not in the direction predicted by the ancestral diet hypothesis. Also, bacterial products were correlated with hormone release that were different from those normally thought to play this role. By comparing microbiota and diets outside the natural range for modern humans, we found a relationship between diet and appetite pathways that was more complex than previously hypothesized on the basis of more-controlled studies of the effects of single compounds.

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Barrier development during the Holocene is studied using the example of the Ilha Comprida, Southeastern Brazil. Aerial photos, facies analysis, and optically stimulated luminescence dating are used to define the barrier emergence and evolution. Optically stimulated luminescence ages and facies successions indicate that the Ilha Comprida probably began as a Holocene transgressive barrier island 6000 years ago, just before the last relative sea-level maximum. Since then the barrier has progradated through the addition of curved beach ridges. Based on beach ridge alignments, six units of growth are identified with two growth directions, transverse and longitudinal. Rates of progradation with transverse growth vary from 0.13 to 4.6 m/year. Rates of longitudinal growth to NE range from 5.2 to 30 m/year. Variation in coastal progradation rates and sediment retention during the last 6000 years is compared with climate, physiography and relative sea-level changes. The physiography, represented by pre-Cenozoic hills, is the major control on sediment retention and alternation between longitudinal and transverse growth. Climate variations, such as the Little Ice Age event, apparently control the formation of ridges types: beach ridges, foredunes, and blowouts. These results allow the use of the Ilha Comprida Barrier as an example to analyze the major controls on barriers progradation. (C) 2011 Elsevier B.V. All rights reserved.

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Although food is a vital part of the chemical process of life, the manner in which people choose the foods that they eat is subject to a wide variety of external and internal influences. This study employed a sequential mixed method research design to investigate the influence of perceived body image, vanity and personal values on food purchasing behaviour among 18- to 30-year-old females. It was found that although personal values and orientation have a major influence on the food purchasing and consumption process, vanity, physical health and perceived body image were major factors of influence in the purchasing and consumption decision.

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In many lowland floodplains around the world, upriver interferences to flows (weirs, dams, off-takes) have led to much reduced frequency and duration of flooding. As a result, many floodplain wetlands are now inundated relatively rarely if at all. Given regulation of most lowland rivers in southeastern Australia, we assessed use of wetlands by birds in the essentially unregulated Ovens River in northeastern Victoria. Twelve sites (0.4-1.2 ha) were studied after flooding. Four sites were 'permanent billabongs', four were temporary wetlands and the other four were randomly selected woodland sites >60 m from the nearest water body (including the river) acting as 'control' or 'reference' sites. Aquatic birds were not recorded using woodland sites, but many species were differentially associated with either billabongs or temporary wetlands. A surprising number of non-aquatic birds either exclusively or differentially were associated with wetland sites compared with woodland sites. We concluded that heterogeneous macrohabitat will increase local avian biodiversity on lowland floodplains. Moreover, densities and diversity of non-aquatic, woodland species also increased with the presence of wetlands. Temporary wetlands were used differently from permanent billabongs by birds, especially in foraging methods. This suggests that the reinstatement of major flooding on heavily regulated floodplains would be ecologically advantageous for birds by providing foraging and breeding opportunities.

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This presentation discusses some of the major pressures on universities to frame curriculum around employability skills and professional requirements. Recent evaluation of Australian university courses by graduates suggests that many institutions remain perplexed as to how to do this. The presentation suggests that the student evaluations do not necessarily indicate poor curriculum development but possibly a lack of making skill development more overt through teaching and assessment. The main objective of this presentation is to outline and describe a project on how curriculum needs to and can respond to professional needs and what this may entail for the way in which traditional professional courses are taught and assessed. The presentation seeks to involve participants in identifying and discussing options for the teaching and assessment of skills and possible options for how these skills can be progressively developed throughout a course of study.

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This Paper examines the cultural impact on the choice of entry mode strategies of Australian companies entering the Chinese Market. The Paper stresses the view that cultural differences must be considered when making entry mode  decisions. The evidence gained from an analysis of case studies undertaken of two Australian companies is presented in this paper. In both cases cultural differences have major affects on the decision-making process of China operations at a strategic level. It also indicates that a uniform process of entry mode stages, as suggested in the literature on entry options, may not be  suitable. Entry mode strategy should be determined on a case-by-case base and evaluated with culture considered prior to other criteria.

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The nature of the species in solution plays a major role on the effectiveness of the corrosion inhibitor on a steel substrate. The speciation of lanthanum 4-hydroxy cinnamate (La(4OHCin) 3) in solution has been evaluated using experimental techniques composed of potentiodynamic polarisation, immersion tests, nuclear magnetic spectroscopy and mass spectroscopy. It is evident that the species in solution are dependent on pH and this impacts the corrosion inhibition mechanism and the efficiency. It was found that at a neutral pH of 5.5 the La(4OH-Cin)3 behaves as a strong anodic inhibitor. Whereas, when the pH shifts to low (pH2.5) and/or high (pH8) the corrosion mechanism changes.

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During the early years, parents have a major influence on their children's diets, food choices and development of eating habits. However, research concerning the influence of parental feeding practices on young children's diets is limited. This paper presents a systematic review of intervention studies with parents of preschool children. The aim was to investigate the effectiveness of interventions that target parent nutrition knowledge and/or parenting practices with parents of young children aged two to five years in the development of healthy dietary habits. Seventeen studies were identified. Findings highlight the limited number of good quality studies in this age group. Limitations include design inconsistency and a lack of longitudinal data to evaluate sustainability. Research on parental understanding of healthy diets and specific parenting styles and feeding practices is lacking. Further insights into how parents can positively influence children's diets will come from quality longitudinal research examining both parent feeding practices and nutrition knowledge in this age group.

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The fisheries sector in the course of the last three decades have been transformed from a developed country to a developing country dominance. Aquaculture, the farming of waters, though a millennia old tradition during this period has become a significant contributor to food fish production, currently accounting for nearly 50 % of global food fish consumption; in effect transforming our dependence from a hunted to a farmed supply as for all our staple food types. Aquaculture and indeed the fisheries sector as a whole is predominated in the developing countries, and accordingly the development strategies adopted by the sector are influenced by this. Aquaculture also being a newly emerged food production sector has being subjected to an increased level of public scrutiny, and one of the most contentious aspects has been its impacts on biodiversity. In this synthesis an attempt is made to assess the impacts of aquaculture on biodiversity. Instances of major impacts on biodiversity conservation arising from aquaculture, such as land use, effluent discharge, effects on wild populations, alien species among others are highlighted and critically examined. The influence of paradigm changes in development strategies and modern day market forces have begun to impact on aquaculture developments. Consequently, improvements in practices and adoption of more environmentally friendly approaches that have a decreasing negative influence on biodiversity conservation are highlighted. An attempt is also made to demonstrate direct and or indirect benefits of aquaculture, such as through being a substitute to meet human needs for food, particularly over-exploited and vulnerable fish stocks, and for other purposes (e.g. medicinal ingredients), on biodiversity conservation, often a neglected entity.

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Intimate partner violence (IPV) has major affects on women’s wellbeing. There has been limited investigation of the association between type and severity of IPV and health outcomes. This article describes socio-demographic characteristics, experiences of abuse, health, safety, and use of services in women enrolled in the Women’s Evaluation of Abuse and Violence Care (WEAVE) project. We explored associations between type and severity of abuse and women’s health, quality of life, and help seeking. Women (aged 16–50 years) attending 52 Australian general practices, reporting fear of partners in last 12 months were mailed a survey between June 2008 and May 2010. Response rate was 70.5% (272/386). In the last 12 months, one third (33.0%) experienced Severe Combined Abuse, 26.2% Physical and Emotional Abuse, 26.6% Emotional Abuse and/or Harassment only, 2.7% Physical Abuse only and 12.4% scored negative on the Composite Abuse Scale. A total of 31.6% of participants reported poor or fair health and 67.9% poor social support. In the last year, one third had seen a psychologist (36.6%) or had 5 or more general practitioner visits (34.3%); 14.7% contacted IPV services; and 24.4% had made a safety plan. Compared to other abuse groups, women with Severe Combined Abuse had poor quality of life and mental health, despite using more medications, counseling, and IPV services and were more likely to have days out of role because of emotional issues. In summary, women who were fearful of partners in the last year, have poor mental health and quality of life, attend health care services frequently, and domestic violence services infrequently. Those women experiencing severe combined physical, emotional, and sexual abuse have poorer quality of life and mental health than women experiencing other abuse types. Health practitioners should take a history of type and severity of abuse for women with mental health issues to assist access to appropriate specialist support.

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Invasive species can induce shifts in habitat use by native taxa: either by modifying habitat availability, or by repelling or attracting native species to the vicinity of the invader. The ongoing invasion of cane toads (Rhinella marina) through tropical Australia might affect native frogs by affecting refuge-site availability, because both frogs and toads frequently shelter by day in burrows. Our laboratory and field studies in the wet-dry tropics show that native frogs of at least three species (Litoria tornieri, Litoria nasuta and Litoria dahlii) preferentially aggregate with conspecifics, and with (some) other species of native frogs. However, the frogs rarely aggregated with cane toads either in outdoor arenas or in standardized experimental burrows that we monitored in the field. The native frogs that we tested either avoided burrows containing cane toads (or cane toad scent) or else ignored the stimulus (i.e. treated such a burrow in the same way as they did an empty burrow). Native frogs selected a highly non-random suite of burrows as diurnal retreat sites, whereas cane toads were less selective. Hence, even in the absence of toads, frogs do not use many of the burrows that are suitable for toads. The invasion of cane toads through tropical Australia is unlikely to have had a major impact on retreat-site availability for native frogs.

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We determined the interaction of diet and exercise-training intensity on membrane phospholipid fatty acid (FA) composition in skeletal muscle from 36 female Sprague-Dawley rats. Animals were randomly divided into one of two dietary conditions: high-carbohydrate (64.0% carbohydrate by energy, n = 18) or high fat (78.1% fat by energy, n = 18). Rats in each diet condition were then allocated to one of three subgroups: control, which performed no exercise training; low-intensity (8 m/min) treadmill run training; or high-intensity (28 m/min) run training. All exercise-trained rats ran 1,000 m/session, 4 days/wk for 8 wk and were killed 48 h after the last training bout. Membrane phospholipids were extracted, and FA composition was determined in the red and white vastus lateralis muscles, Diet exerted a major influence on phospholipid FA composition, with the high-fat diet being associated with a significantly (P < 0.01) elevated ratio of n-6/n-3 FA for both red (2.7-3.2 vs. 1.0-1.1) and white vastus lateralis muscle (2.5-2.9 vs. 1.2). In contrast, alterations in FA composition as a result of either exercise-training protocol were only minor in comparison. We conclude that, under the present experimental conditions, a change in the macronutrient content of the diet was a more potent modulator of skeletal muscle membrane phospholipid FA composition compared with either low- or high-intensity treadmill exercise training.

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Parents have a major influence on young children's diets, food choices and habit formation. However, research concerning parental influence on children's diets is limited. Qualitative research informs quantitative research with a narrative of 'what works' and is a valuable tool to inform intervention design and practice. This article presents a systematic review of qualitative research with parents of preschool children and their influence on their child's diet. Nine studies were identified. Findings highlight the need to promote culturally tailored programmes to combat specific cultural differences such as attitudes; perceptions and concerns; address common barriers to providing healthy foods and challenges faced by lower income families; the use of food to shape a child's behaviour; that children will grow out of excess weight; common misconceptions such as a heavier child is healthier and depriving a child's food request could result in starvation. Research on parental understanding of healthy diets and feeding practices is lacking. Further insights into how to positively influence children's diets will come from research examining parent feeding practices and nutrition knowledge. © The Author(s) 2013.

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BACKGROUND: Adolescent depression is a prevalent mental health problem, which can have a major impact on family cohesion. In such circumstances, excessive use of the Internet by adolescents may exacerbate family conflict and lack of cohesion. The current study aims to explore these patterns within an intervention study for depressed adolescents.

METHOD: The current study draws upon data collected from parents within the family options randomized controlled trial that examined family based interventions for adolescent depression (12-18 years old) in Melbourne, Australia (2012-2014). Inclusion in the trial required adolescents to meet diagnostic criteria for a major depressive disorder via the Structured Clinical Interview for DSM-IV Childhood Disorders. The transcripts of sessions were examined using qualitative thematic analysis. The transcribed sessions consisted of 56 h of recordings in total from 39 parents who took part in the interventions.

RESULTS: The thematic analysis explored parental perceptions of their adolescent's use of social media (SM) and access to Internet content, focusing on the possible relationship between adolescent Internet use and the adolescent's depressive disorder. Two overarching themes emerged as follows: the sense of loss of parental control over the family environment and parents' perceived inability to protect their adolescent from material encountered on the Internet and social interactions via SM.

CONCLUSION: Parents within the context of family based treatments felt that prolonged exposure to SM exposed their already vulnerable child to additional stressors and risks. The thematic analysis uncovered a sense of parental despair and lack of control, which is consistent with their perception of SM and the Internet as relentless and threatening to their parental authority and family cohesion.