49 resultados para maladaptive coping
Resumo:
We describe the nature of recent (50 year) rainfall variability in the summer rainfall zone, South Africa, and how variability is recognised and responded to on the ground by farmers. Using daily rainfall data and self-organising mapping (SOM) we identify 12 internally homogeneous rainfall regions displaying differing parameters of precipitation change. Three regions, characterised by changing onset and timing of rains, rainfall frequencies and intensities, in Limpopo, North West and KwaZulu Natal provinces, were selected to investigate farmer perceptions of, and responses to, rainfall parameter changes. Village and household level analyses demonstrate that the trends and variabilities in precipitation parameters differentiated by the SOM analysis were clearly recognised by people living in the areas in which they occurred. A range of specific coping and adaptation strategies are employed by farmers to respond to climate shifts, some generic across regions and some facilitated by specific local factors. The study has begun to understand the complexity of coping and adaptation, and the factors that influence the decisions that are taken.
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Many multicellular organisms have evolved a dedicated germline. This can benefit the whole organism, but its advantages to genetic parasites have not been explored. Here I model the evolutionary success of a selfish element, such as a transposable element or endosymbiont, which is capable of creating or strengthening a germline-soma distinction in a primitively multicellular host, and find that it will always benefit the element to do so. Genes causing germline sequestration can therefore spread in a population even if germline sequestration is maladaptive for the host organism. Costly selfish elements are expected to survive only in sexual populations, so sexual species may experience an additional push toward germline-soma distinction, and hence toward cell differentiation and multicellularity.
Resumo:
In recent decades, immigrants, refugees and asylum seekers have sought a new way of life in large numbers, often leaving their countries of origin behind in search of places that offer a better way of life. The purpose of this study was to investigate how elementary and middle school students in state schools in Reading, England (primarily speakers of Asian languages), and Richmond, Virginia (primarily speakers of Spanish), were supported academically, when most children's first language was not English. The authors were interested in exploring whether or not there were cultural or structural differences in the way each country helped or hindered these students as they progressed through the school systems. Three UK schools in a district of approximately 100,000 and three US schools in a district of approximately 250,000 were the focus of this exploration from 2000 to 2003. Findings indicated that there were cultural and legislative differences and similarities. Teachers and administrators in both countries attempted to provide services with limited and sometimes diminishing resources. Community support varied based on resources, attitudes toward various ethnic groups, and the coping strategies adopted by these groups in their new environments. Marked differences appeared with regard to the manner in which assessments took place and how the results were made available to the public.
Resumo:
Coronary artery disease is one of the most common heart pathologies. Restriction of blood flow to the heart by atherosclerotic lesions, leading to angina pectoris and myocardial infarction, damages the heart, resulting in impaired cardiac function. Damaged myocardium is replaced by scar tissue since surviving cardiomyocytes are unable to proliferate to replace lost heart tissue. Although narrowing of the coronary arteries can be treated successfully using coronary revascularisation procedures, re-occlusion of the treated vessels remains a significant clinical problem. Cell cycle control mechanisms are key in both the impaired cardiac repair by surviving cardiomyocytes and re-narrowing of treated vessels by maladaptive proliferation of vascular smooth muscle cells. Strategies targeting the cell cycle machinery in the heart and vasculature offer promise both for the improvement of cardiac repair following MI and the prevention of restenosis and bypass graft failure following revascularisation procedures.
Resumo:
Two constructs were hypothesized to be of importance in psychological disorders: persistence (the ability to keep going to reach a goal, even when the task is difficult or drawn out) and perseveration (the tendency to continue a behavior, even when it ceases to be effective or rewarding). These are contrasted with perfectionism (having high standards for oneself or others). A measure was developed to address these constructs (the Persistence, Perseveration and Perfectionism Questionnaire; PPPQ). The PPPQ was administered to 325 nonclinical participants, alongside a measure of psychological disturbance. Factor analysis resulted in a 22-item version of the measure, consisting of subscales with good psychometric properties corresponding to the 3 theoretical constructs. Persistence was associated with lower levels of psychopathology, whereas perseveration was associated with higher levels of psychopathology. Perfectionism was weakly associated with psychopathology. Further work is needed to develop these constructs with clinical groups, but the findings support the hypothesis that persistence is an adaptive construct whereas perseveration is maladaptive.
Resumo:
To investigate sources of influences connecting mothers' and their children's anxious cognitions, 65 children (aged 10 to 11 years) completed self-report measures of anxiety. Children and mothers responded to an ambiguous scenario questionnaire and measures of parenting style and life events. Mothers also reported expectations about their child's reaction to ambiguous situations. Mothers' and children's threat cognitions were significantly correlated (r = .31), and partially mediated by mothers' expectations about their child. Mothers' anticipated distress was associated with expectations for their child's distress, which was associated with the child's own anticipated distress. Parenting and life events were significantly associated with children's interpretative bias, but did not mediate the intergenerational association in interpretative bias. The results suggest influences on children's 'anxious cognitive style' and potential targets for preventing and reducing maladaptive cognitions in children.
Resumo:
Garment information tracking is required for clean room garment management. In this paper, we present a camera-based robust system with implementation of Optical Character Reconition (OCR) techniques to fulfill garment label recognition. In the system, a camera is used for image capturing; an adaptive thresholding algorithm is employed to generate binary images; Connected Component Labelling (CCL) is then adopted for object detection in the binary image as a part of finding the ROI (Region of Interest); Artificial Neural Networks (ANNs) with the BP (Back Propagation) learning algorithm are used for digit recognition; and finally the system is verified by a system database. The system has been tested. The results show that it is capable of coping with variance of lighting, digit twisting, background complexity, and font orientations. The system performance with association to the digit recognition rate has met the design requirement. It has achieved real-time and error-free garment information tracking during the testing.
Resumo:
Alterations to the genetic code – codon reassignments – have occurred many times in life’s history, despite the fact that genomes are coadapted to their genetic codes and therefore alterations are likely to be maladaptive. A potential mechanism for adaptive codon reassignment, which could trigger either a temporary period of codon ambiguity or a permanent genetic code change, is the reactivation of a pseudogene by a nonsense suppressor mutant transfer RNA. I examine the population genetics of each stage of this process and find that pseudogene rescue is plausible and also readily explains some features of extant variability in genetic codes.
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1. The evolution of host resistance to parasitoid attack will be constrained by two factors: the costs of the ability to defend against attack, and the costs of surviving actual attack. These factors have been investigated using Drosophila melanogaster and its parasitoids as a model system. The costs of defensive ability are expressed as a trade-off with larval competitive ability, whereas the costs of actual defence are exhibited in terms of reduced adult fecundity and size. 2. The costs of actual defence may be ameliorated by the host-choice decisions made by Pachycrepoideus vindemiae, a pupal parasitoid. If larvae that have successfully encapsulated a parasitoid develop into poorer quality hosts, then these may be rejected by ovipositing pupal parasitoids. 3. Pupae developing from larvae that have encapsulated the parasitoid Asobara tabida are smaller and have relatively thinner puparia. Thinner puparia are likely to be associated with a reduction in mechanical strength and possibly with a decrease in desiccation tolerance. 4. Pachycrepoideus vindemiae that develop in capsule-bearing pupae are smaller than those that emerge from previously unattacked hosts. This supports the prediction that ovipositing female P. vindemiae should avoid attacking capsule-bearing hosts. However, in choice experiments with 1-day-old pupae, P. vindemiae females oviposited preferentially in hosts containing a capsule, whereas there was no preference found with 4-day-old hosts. This appears to be a maladaptive host choice decision, as the female pupal parasitoids are preferentially attacking hosts that will result in a reduction of their own fitness. 5. The increased likelihood of attack by a pupal parasitoid is another cost of actual defence against larval parasitoid attack.
Resumo:
This paper investigates whether and to what extent a wide range of actors in the UK are adapting to climate change, and whether this is evidence of a social transition. We document evidence of over 300 examples of early adopters of adaptation practice to climate change in the UK. These examples span a range of activities from small adjustments (or coping) to building adaptive capacity, implementing actions and creating deeper systemic change in public and private organisations in a range of sectors. We find that adaptation in the UK has been dominated by government initiatives and has principally occurred in the form of research into climate change impacts. These actions within government stimulate a further set of actions at other scales in public agencies, regulatory agencies and regional government (or in the devolved administrations), though with little real evidence of climate change adaptation initiatives trickling down to local government level. The water supply and flood defence sectors, requiring significant investment in large scale infrastructure such as reservoirs and coastal defences, have invested more heavily in identifying potential impacts and adaptations. Economic sectors that are not dependent on large scale infrastructure appear to be investing far less effort and resources in preparing for climate change. We conclude that while the government-driven top-down targeted adaptation approach has generated anticipatory action at low cost, it may also have created enough niche activities to allow for diffusion of new adaptation practices in response to real or perceived climate change. These results have significant implications for how climate policy can be developed to support autonomous adaptors in the UK and other countries.
Resumo:
Objectives This study aimed to investigate post-traumatic stress symptoms (PTSS) in childhood brain tumour survivors and their parents. A further aim was to explore the relationship between objective illness parameters, parent–child interactions, coping styles and PTSS. Methods A cross-sectional correlational design was employed. Fifty-two childhood brain tumour survivors, aged 8–16, and 52 parents completed a battery of questionnaires designed to assess quality of parent–child interactions, monitoring and blunting attentional coping styles and PTSS. Results Over one-third (35%) of survivors and 29% of their parents reported severe levels of PTSS (suggestive of post-traumatic stress disorder ‘caseness’). Increased parent–child conflict resolution for survivors and number of tumour recurrences for parents independently predicted the variance in PTSS. Conclusions For a substantial proportion of brain tumour survivors and their parents the process of survivorship is a considerably distressing experience.
Resumo:
Although the use of climate scenarios for impact assessment has grown steadily since the 1990s, uptake of such information for adaptation is lagging by nearly a decade in terms of scientific output. Nonetheless, integration of climate risk information in development planning is now a priority for donor agencies because of the need to prepare for climate change impacts across different sectors and countries. This urgency stems from concerns that progress made against Millennium Development Goals (MDGs) could be threatened by anthropogenic climate change beyond 2015. Up to this time the human signal, though detectable and growing, will be a relatively small component of climate variability and change. This implies the need for a twin-track approach: on the one hand, vulnerability assessments of social and economic strategies for coping with present climate extremes and variability, and, on the other hand, development of climate forecast tools and scenarios to evaluate sector-specific, incremental changes in risk over the next few decades. This review starts by describing the climate outlook for the next couple of decades and the implications for adaptation assessments. We then review ways in which climate risk information is already being used in adaptation assessments and evaluate the strengths and weaknesses of three groups of techniques. Next we identify knowledge gaps and opportunities for improving the production and uptake of climate risk information for the 2020s. We assert that climate change scenarios can meet some, but not all, of the needs of adaptation planning. Even then, the choice of scenario technique must be matched to the intended application, taking into account local constraints of time, resources, human capacity and supporting infrastructure. We also show that much greater attention should be given to improving and critiquing models used for climate impact assessment, as standard practice. Finally, we highlight the over-arching need for the scientific community to provide more information and guidance on adapting to the risks of climate variability and change over nearer time horizons (i.e. the 2020s). Although the focus of the review is on information provision and uptake in developing regions, it is clear that many developed countries are facing the same challenges. Copyright © 2009 Royal Meteorological Society
Resumo:
A novel algorithm for solving nonlinear discrete time optimal control problems with model-reality differences is presented. The technique uses Dynamic Integrated System Optimisation and Parameter Estimation (DISOPE) which has been designed to achieve the correct optimal solution in spite of deficiencies in the mathematical model employed in the optimisation procedure. A method based on Broyden's ideas is used for approximating some derivative trajectories required. Ways for handling con straints on both manipulated and state variables are described. Further, a method for coping with batch-to- batch dynamic variations in the process, which are common in practice, is introduced. It is shown that the iterative procedure associated with the algorithm naturally suits applications to batch processes. The algorithm is success fully applied to a benchmark problem consisting of the input profile optimisation of a fed-batch fermentation process.
Resumo:
Diabetes like many diseases and biological processes is not mono-causal. On the one hand multifactorial studies with complex experimental design are required for its comprehensive analysis. On the other hand, the data from these studies often include a substantial amount of redundancy such as proteins that are typically represented by a multitude of peptides. Coping simultaneously with both complexities (experimental and technological) makes data analysis a challenge for Bioinformatics.
Resumo:
This paper explores the impacts of the HIV/AIDS epidemic on children and families in northern Tanzania using the concept of social resilience.1 The study is based on the findings of childfocused research with street children and children and families from HIV/AIDS-affected households. The paper illustrates the coping strategies that children and young people, and parents and caregivers adopt at the household level. In particular, it examines how the burden of care affects different generations of women and highlights their resilience, together with the importance of social networks and the fluidity of movement between rural and urban areas. The research suggests that migrating to urban areas to seek a living in the informal sector represents a survival strategy adopted by some children and young people orphaned by AIDS when their families and communities are unable or unwilling to support them. The paper concludes by exploring parents’, caregivers’, children’s, and young people’s views on the forms of social support that would promote their resilience and thereby help to mitigate the impacts of the epidemic at the household level.