949 resultados para Post-feeding Larval Dispersal
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This manual consists of written descriptions of jungle perch Kuhlia rupestris production and video material to demonstrate each of the key production steps. Video links are at the end of each major written section in the document. To activate the link use ctrl click. The videos enhance the instructive ability of this manual. The keys to producing jungle perch are: maintaining broodstock in freshwater or low salinity water less than 5 ppt spawning fish in full seawater at 28C incubating eggs in full seawater. Salinities must not be less than 32 ppt ensuring that first feed jungle perch larvae have an adequate supply of copepod nauplii rearing larvae in full seawater under bright light use of gentle aeration in tanks postponing spawns until adequate densities of copepod nauplii are present in ponds sustaining copepod blooms in ponds for at least 20 days avoiding use of paddlewheels in ponds supplementary feeding with Artemia salina and weaning diets from 20 days after hatch harvesting of fingerlings or fry after they are 25-30 mm in length (50 to 60 days post hatch) covering tanks of fingerlings with 5 mm mesh and submerging freshwater inlets to prevent jumping.
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Some evidence suggests that behavioural and psychological symptoms of dementia (BPSD) are more pronounced in veterans with a history of post-traumatic stress disorder (PTSD) than in others with dementia. Catherine Travers, Elizabeth Beattie and Elaine Fielding surveyed Australian healthcare professionals to better understand whether PTSD influences the expression of these symptoms in veterans with dementia.
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OBJECTIVE: Lower limb amputation is often associated with a high risk of early post-operative mortality. Mortality rates are also increasingly being put forward as a possible benchmark for surgical performance. The primary aim of this systematic review is to investigate early post-operative mortality following a major lower limb amputation in population/regional based studies, and reported factors that might influence these mortality outcomes. METHODS: Embase, PubMed, Cinahl and Psycinfo were searched for publications in any language on 30 day or in hospital mortality after major lower limb amputation in population/regional based studies. PRISMA guidelines were followed. A self developed checklist was used to assess quality and susceptibility to bias. Summary data were extracted for the percentage of the population who died; pooling of quantitative results was not possible because of methodological differences between studies. RESULTS: Of the 9,082 publications identified, results were included from 21. The percentage of the population undergoing amputation who died within 30 days ranged from 7% to 22%, the in hospital equivalent was 4-20%. Transfemoral amputation and older age were found to have a higher proportion of early post-operative mortality, compared with transtibial and younger age, respectively. Other patient factors or surgical treatment choices related to increased early post-operative mortality varied between studies. CONCLUSIONS: Early post-operative mortality rates vary from 4% to 22%. There are very limited data presented for patient related factors (age, comorbidities) that influence mortality. Even less is known about factors related to surgical treatment choices, being limited to amputation level. More information is needed to allow comparison across studies or for any benchmarking of acceptable mortality rates. Agreement is needed on key factors to be reported.
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This research investigated the efficacy of a post-discharge nurse-led clinic, for patients who underwent a cardiovascular interventional procedure in Australia. A randomised controlled clinical trial measured the effects of the clinic on patient confidence to self-manage and minimise psychological distress given the strong link between anxiety, depression and coronary heart disease. Hospitalisation for the procedure is short and stressful, and patients may wait up to 7-64 days for post-discharge review. This study provides preliminary quantitative and qualitative evidence that nurse-led clinics undertaken within the first week post-percutaneous coronary intervention may fill a much-needed gap for patients during a potentially vulnerable period.
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Austria and Finland are persistently referred to as the “success stories” of post-1945 European history. Notwithstanding their different points of departure, in the course of the Cold War both countries portrayed themselves as small and neutral border-states in the world dictated by superpower politics. By the 1970s, both countries frequently ranked at the top end in various international classifications regarding economic development and well-being in society. This trend continues today. The study takes under scrutiny the concept of consensus which figures centrally in the two national narratives of post-1945 success. Given that the two domestic contexts as such only share few direct links with one another and are more obviously different than similar in terms of their geographical location, historical experiences and politico-cultural traditions, the analogies and variations in the anatomies of the post-1945 “cultures of consensus” provide an interesting topic for a historical comparative and cross-national examination. The main research question concerns the identification and analysis of the conceptual and procedural convergence points of the concepts of the state and consensus. The thesis is divided into six main chapters. After the introduction, the second chapter presents the theoretical framework in more detail by focusing on the key concepts of the study – the state and consensus. Chapter two also introduces the comparative historical and cross-national research angles. Chapter three grounds the key concepts of the state and consensus in the historical contexts of Austria and Finland by discussing the state, the nation and democracy in a longer term comparative perspective. The fourth and fifth chapter present case studies on the two policy fields, the “pillars”, upon which the post-1945 Austrian and Finnish cultures of consensus are argued to have rested. Chapter four deals with neo-corporatist features in the economic policy making and chapter five discusses the building up of domestic consensus regarding the key concepts of neutrality policies in the 1950s and 1960s. The study concludes that it was not consensus as such but the strikingly intense preoccupation with the theme of domestic consensus that cross-cut, in a curiously analogous manner, the policy-making processes studied. The main challenge for the post-1945 architects of Austrian and Finnish cultures of consensus was to find strategies and concepts for consensus-building which would be compatible with the principles of democracy. Discussed at the level of procedures, the most important finding of the study concerns the triangular mechanism of coordination, consultation and cooperation that set into motion and facilitated a new type of search for consensus in both post-war societies. In this triangle, the agency of the state was central, though in varying ways. The new conceptions concerning a small state’s position in the Cold War world also prompted cross-nationally perceivable willingness to reconsider inherited concepts and procedures of the state and the nation. At the same time, the ways of understanding the role of the state and its relation to society remained profoundly different in Austria and Finland and this basic difference was in many ways reflected in the concepts and procedures deployed in the search for consensus and management of domestic conflicts. For more detailed information, please consult the author.
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This work is concerned with presenting a modified theoretical approach to the study of centre-periphery relations in the Russian Federation. In the widely accepted scientific discourse, the Russian federal system under the Yeltsin Administration (1991-2000) was asymmetrical; largely owing to the varying amount of structural autonomy distributed among the federation s 89 constituent units. While providing an improved understanding as to which political and socio-economic structures contributed to federal asymmetry, it is felt that associated large N-studies have underemphasised the role played by actor agency in re-shaping Russian federal institutions. It is the main task of this thesis to reintroduce /re-emphasise the importance of actor agency as a major contributing element of institutional change in the Russian federal system. By focusing on the strategic agency of regional elites simultaneously within regional and federal contexts, the thesis adopts the position that political, ethnic and socio-economic structural factors alone cannot fully determine the extent to which regional leaders were successful in their pursuit of economic and political pay-offs from the institutionally weakened federal centre. Furthermore, this work hypothesises that under conditions of federal institutional uncertainty, it is the ability of regional leaders to simultaneously interpret various mutable structural conditions then translate them into plausible strategies which accounts for the regions ability to extract variable amounts of economic and political pay-offs from the Russian federal system. The thesis finds that while the hypothesis is accurate in its theoretical assumptions, several key conclusions provide paths for further inquiry posed by the initial research question. First, without reliable information or stable institutions to guide their actions, both regional and federal elites were forced into ad-hoc decision-making in order to maintain their core strategic focus: political survival. Second, instead of attributing asymmetry to either actor agency or structural factors exclusively, the empirical data shows that both agency and structures interact symbiotically in the strategic formulation process, thus accounting for the sub-optimal nature of several of the actions taken in the adopted cases. Third, as actor agency and structural factors mutate over time, so, too do the perceived payoffs from elite competition. In the case of the Russian federal system, the stronger the federal centre became, the less likely it was that regional leaders could extract the high degree of economic and political pay-offs that they clamoured for earlier in the Yeltsin period. Finally, traditional approaches to the study of federal systems which focus on institutions as measures of federalism are not fully applicable in the Russian case precisely because the institutions themselves were a secondary point of contention between competing elites. Institutional equilibriums between the regions and Moscow were struck only when highly personalised elite preferences were satisfied. Therefore the Russian federal system is the product of short-term, institutional solutions suited to elite survival strategies developed under conditions of economic, political and social uncertainty.
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In April 2014, the World Health Organization announced the beginning of a post-antibiotic era and declared antimicrobial resistance (AMR) a public health priority demanding global action. If no action is taken, by 2050 AMR will kill more people each year than cancer, with 10 million estimated annual deaths at a cost of $100 trillion to the global economy. New therapies to tackle multidrug resistant bacterial pathogens are urgently needed. Unlike traditional antibiotics, antivirulence drugs inhibit bacterial virulence instead of growth promising to offer a new class of superior therapeutics that will be ‘evolution-proof’ and ‘tailored-spectrum’. This mini-review discusses the latest emerging evidence on the promised benefits of antivirulence drugs over conventional antibiotics, also highlighting the challenges in evaluating these properties for each of the diverse virulence targets that are currently under investigation. The author argues that overcoming such challenges early in the development process constitutes an important step towards successfully progressing each of the expanding number of antivirulence strategies into next-generation therapies for common human and animal infections that are becoming increasingly refractory to all available antibiotics.
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This paper by Carl Grodach demonstrates the careful unravelling of complexity, diversity, contestation and contradictions involved in the reconstruction of symbolic urban spaces after violent conflict, and the allied processes of cultural reinterpretation, political reconfiguration and material revaluation which accompany it. The paper analyses the reconstruction and redevelopment of the 16th-century historic centre of Mostar, Bosnia-Herzegovina, following the Bosnian Wars of 1992–1995. Reconstruction efforts centre around Stari Most, the 16th-century Ottoman bridge destroyed by Bosnian Croat military in 1993. In Mostar, both international and local organizations are in the process of reinterpreting Bosnia’s legacy of Ottoman city spaces. This research and analysis illuminates how such spaces can be central to contemporary projects to redefine group identities and conceptions of place. It provides insight into the ways various groups are attempting to reshape outside perceptions of the city—and Bosnia’s ethnic conflict—to articulate a new definition of local identity and ethnic relations and to remake a stable tourist economy through Mostar’s urban spaces.
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Spatial and temporal variation in the abundance of species can often be ascribed to spatial and temporal variation in the surrounding environment. Knowledge of how biotic and abiotic factors operate over different spatial and temporal scales in determining distribution, abundance, and structure of populations lies at the heart of ecology. The major part of the current ecological theory stems from studies carried out in central parts of the distributional range of species, whereas knowledge of how marginal populations function is inadequate. Understanding how marginal populations, living at the edge of their range, function is however in a key position to advance ecology and evolutionary biology as scientific disciplines. My thesis focuses on the factors affecting dynamics of marginal populations of blue mussels (Mytilus edulis) living close to their tolerance limits with regard to salinity. The thesis aims to highlight the dynamics at the edge of the range and contrast these with dynamics in more central parts of the range in order to understand the potential interplay between the central and the marginal part in the focal system. The objectives of the thesis are approached by studies on: (1) factors affecting regional patterns of the species, (2) long-term temporal dynamics of the focal species spaced along a regional salinity gradient, (3) selective predation by increasing populations of roach (Rutilus rutilus) when feeding on their main food item, the blue mussel, (4) the primary and secondary effects of local wave exposure gradients and (5) the role of small-scale habitat heterogeneity as determinants of large-scale pattern. The thesis shows that populations of blue mussels are largely determined by large scale changes in sea water salinity, affecting mainly recruitment success and longevity of local populations. In opposite to the traditional view, the thesis strongly indicate that vertebrate predators strongly affect abundance and size structure of blue mussel populations, and that the role of these predators increases towards the margin where populations are increasingly top-down controlled. The thesis also indicates that the positive role of biogenic habitat modifiers increases towards the marginal areas, where populations of blue mussels are largely recruitment limited. Finally, the thesis shows that local blue mussel populations are strongly dependent on high water turbulence, and therefore, dense populations are constrained to offshore habitats. Finally, the thesis suggests that ongoing sedimentation of rocky shores is detrimental for the species, affecting recruitment success and post-recruit survival, pushing stable mussel beds towards offshore areas. Ongoing large scale changes in the Baltic Sea, especially dilution processes with attendant effects, are predicted to substantially contract the distributional range of the mussel, but also affect more central populations. The thesis shows that in order to understand the functioning of marginal populations, research should (1) strive for multi-scale approaches in order to link ecosystem patterns with ecosystem processes, and (2) challenge the prevailing tenets that origin from research carried out in central areas that may not be valid at the edge.
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It has been only recently realized that sexual selection does not end at copulation but that post-copulatory processes are often important in determining the fitness of individuals. In this thesis, I experimentally studied both pre- and post-copulatory sexual selection in the least killifish, Heterandria formosa. I found that this species suffers from severe inbreeding depression in male reproductive behaviour, offspring viability and offspring maturation times. Neither sex showed pre-copulatory inbreeding avoidance but when females mated with their brothers, less sperm were retrieved from their reproductive system compared to the situation when females mated with unrelated males. Whether the difference in sperm numbers is due to female or male effect could not be resolved. Based on theory, females should be more eager to avoid inbreeding than males in this species, because females invest more in their offspring than males do. Inbreeding seems to be an important part of this species biology and the severe inbreeding depression has most likely selected for the evolution of the post-copulatory inbreeding avoidance mechanism that I found. In addition, I studied the effects of polyandry on female reproductive success. When females mated with more than one male, they were more likely to get pregnant. However, I also found a cost of polyandry. The offspring of females mated to four males took longer to reach sexual maturity compared to the offspring of monandrous females. This cost may be explained by parent-offspring conflict over maternal resource allocation. In another experiment, in which within-brood relatedness was manipulated, offspring sizes decreased over time when within-brood relatedness was low. This result is partly in accordance with the kinship theory of genomic imprinting. When relatedness decreases, offspring are expected to be less co-operative and demand fewer resources from their mother, which leads to impaired development. In the last chapter of my thesis, I show that H. formosa males do not prefer large females as in other Poeciliidae species. I suggest that males view smaller females as more profitable mates because those are more likely virgin. In conclusion, I found both pre- and post-copulatory sexual selection to be important factors in determining reproductive success in H. formosa.
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Most studies of life history evolution are based on the assumption that species exist at equilibrium and spatially distinct separated populations. In reality, this is rarely the case, as populations are often spatially structured with ephemeral local populations. Therefore, the characteristics of metapopulations should be considered while studying factors affecting life history evolution. Theoretical studies have examined spatial processes shaping the evolution of life history traits to some extent, but there is little empirical data and evidence to investigate model predictions. In my thesis I have tried to bridge the gap between theoretical and empirical studies by using the well-known Glanville fritillary (Melitaea cinxia) metapopulation as a model system. The long-term persistence of classic metapopulations requires sufficient dispersal to establish new local populations to compensate for local extinctions. Previous studies on the Glanville fritillary have shown that females establishing new populations are not a random sample from the metapopulation, but they are in fact more dispersive than females in old populations. Many other life-history traits, such as body size, fecundity and lifespan, may be related to dispersal rate. Therefore, I examined a range of correlated traits for their evolutionary and ecological consequences. I was particularly interested in how the traits vary under natural environmental conditions, hence all studies were conducted in a large (32 x 26 m) outdoor population cage built upon a natural habitat patch. Individuals for the experiments were sampled from newly-established and old populations within a large metapopulation. Results show that females originating from newly-established populations had higher within-habitat patch mobility than females from old populations. I showed that dispersal rate is heritable and that flight activity is related to variation in a gene encoding the glycolytic enzyme phosphoglucose isomerase. Both among-individual and among-population variation in dispersal are correlated with the reproductive performance of females, though I found no evidence for a trade-off between dispersal and fecundity in terms of lifetime egg production or clutch size. Instead, the results suggest that highly dispersive females from newly-established populations have a shorter lifespan than females from old populations, and that dispersive females may pay a cost in terms of reduced lifetime reproductive success due to increased time spent outside habitat patches. In summary, the results of this thesis show that genotype-dependent dispersal rate correlates with other life history traits in the Glanville fritillary, and that the rapid turnover of local populations (extinctions and re-colonisations) is likely to be the mechanism that maintains phenotypic variation in many life history traits at the metapopulation level.