925 resultados para Ecological half-life


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Coastal lagoons are semi-isolated ecosystems exposed to wide fluctuations of environmental conditions and showing habitat fragmentation. These features may play an important role in separating species into different populations, even at small spatial scales. In this study, we evaluate the concordance between mitochondrial (previous published data) and nuclear data analyzing the genetic variability of Pomatoschistus marmoratus in five localities, inside and outside the Mar Menor coastal lagoon (SE Spain) using eight microsatellites. High genetic diversity and similar levels of allele richness were observed across all loci and localities, although significant genic and genotypic differentiation was found between populations inside and outside the lagoon. In contrast to the FST values obtained from previous mitochondrial DNA analyses (control region), the microsatellite data exhibited significant differentiation among samples inside the Mar Menor and between lagoonal and marine samples. This pattern was corroborated using Cavalli-Sforza genetic distances. The habitat fragmentation inside the coastal lagoon and among lagoon and marine localities could be acting as a barrier to gene flow and contributing to the observed genetic structure. Our results from generalized additive models point a significant link between extreme lagoonal environmental conditions (mainly maximum salinity) and P. marmoratus genetic composition. Thereby, these environmental features could be also acting on genetic structure of coastal lagoon populations of P. marmoratus favoring their genetic divergence. The mating strategy of P. marmoratus could be also influencing our results obtained from mitochondrial and nuclear DNA. Therefore, a special consideration must be done in the selection of the DNA markers depending on the reproductive strategy of the species.

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Polymorphic species have been the focus of important work in evolutionary biology. It has been suggested that colour polymorphic species have specific evolutionary and population dynamics that enable them to persist through environmental changes better than less variable species. We suggest that recent empirical and theoretical work indicates that polymorphic species may be more vulnerable to extinction than previously thought. This vulnerability arises because these species often have a number of correlated sexual, behavioural, life history and ecological traits, which can have a simple genetic underpinning. When exacerbated by environmental change, these alternate strategies can lead to conflict between morphs at the genomic and population levels, which can directly or indirectly affect population and evolutionary dynamics. In this perspective, we identify a number of ways in which the nature of the correlated traits, their underpinning genetic architecture, and the inevitable interactions between colour morphs can result in a reduction in population fitness. The principles illustrated here apply to all kinds of discrete polymorphism (e.g. behavioural syndromes), but we focus primarily on colour polymorphism because they are well studied. We urge further empirical investigation of the genetic architecture and interactions in polymorphic species to elucidate the impact on population fitness.

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This paper reports the findings from a research project that examines the relationship between urban design and the physical environment, and aspects of social and communal life in suburbs. Australian suburbs are perceived to be lacking in vitality and sociability. To address this, three suburban commercial streets were selected for investigation. Through documents and maps of the residents’ activities and behaviour, this study aims to identify the popular zones of activity and investigate the physical characteristics that encourage a sociable atmosphere in activity zones. The observation of activities in the three streets has been registered in tables relative to the date and time of occurrence. According to the behavioural mappings, the zones of activity are mostly shaped around pavement cafes and popular everyday food stores. Since more than half the activities have been observed to be initiated from the pavement cafes, this paper will investigate how the physical qualities of commercial streets such as the width of the pavements, personalization, soft edges and greenery have contributed to the pavement café culture in the selected neighbourhood centres.

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'Fire mosaics' are often maintained in landscapes to promote successional diversity in vegetation with little understanding of how this will affect ecological processes in animal populations such as dispersal, social organization and re-establishment. To investigate these processes, we conducted a replicated, spatiotemporal landscape genetics study of two Australian woodland lizard species [Amphibolurus norrisi (Agamidae) and Ctenotus atlas (Scincidae)]. Agamids have a more complex social and territory structure than skinks, so fire might have a greater impact on their population structure and thus genetic diversity. Genetic diversity increased with time since fire in C. atlas and decreased with time since fire in A. norrisi. For C. atlas, this might reflect its increasing population size after fire, but we could not detect increased gene flow that would reduce the loss of genetic diversity through genetic drift. Using landscape resistance analyses, we found no evidence that postfire habitat succession or topography affected gene flow in either species and we were unable to distinguish between survival and immigration as modes of postfire re-establishment. In A. norrisi, we detected female-biased dispersal, likely reflecting its territorial social structure and polygynous mating system. The increased genetic diversity in A. norrisi in recently burnt habitat might reflect a temporary disruption of its territoriality and increased male dispersal, a hypothesis that was supported with a simulation experiment. Our results suggest that the effects of disturbance on genetic diversity will be stronger for species with territorial social organization.

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We tested the two main evolutionary hypotheses for an association between immunity and personality. The risk-of-parasitism hypothesis predicts that more proactive (bold, exploratory, risk-taking) individuals have more vigorous immune defenses because of increased risk of parasite exposure. In contrast, the pace-of-life hypothesis argues that proactive behavioral styles are associated with shorter lifespans and reduced investment in immune function. Mechanistically, associations between immunity and personality can arise because personality differences are often associated with differences in condition and stress responsiveness, both of which are intricately linked with immunity. Here we investigate the association between personality (measured as proactive exploration of a novel environment) and three indices of innate immune function (the non-specific first line of defense against parasites) in wild superb fairy-wrens Malurus cyaneus. We also quantified body condition, hemoparasites (none detected), chronic stress (heterophil:lymphocyte ratio) and circulating corticosterone levels at the end of the behavioral test (CORT, in a subset of birds). We found that fast explorers had lower titers of natural antibodies. This result is consistent with the pace-of-life hypothesis, and with the previously documented higher mortality of fast explorers in this species. There was no interactive effect of exploration score and duration in captivity on immune indices. This suggests that personality-related differences in stress responsiveness did not underlie differences in immunity, even though behavioral style did modulate the effect of captivity on CORT. Taken together these results suggest reduced constitutive investment in innate immune function in more proactive individuals.

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Diamondback terrapins (Malaclemys terrapin) are native to the remote oceanic islands of Bermuda and presently inhabit only four small brackish water ponds on a private golf course. The life history of this species is poorly understood on Bermuda and so the aim of this study was to fill these knowledge gaps, to compare the results with what is known from other areas in the North American range, and to inform the development of a local management plan. The results of a mark-recapture census revealed that ca. 100 individuals ≥81 mm straight carapace length live on Bermuda, of which nearly half (48.5%) were considered sexually mature. The population is dominated by females (sex ratio 2.9:1) and annual recruitment over the three year period was found to be extremely low (approximately two terrapins). Female diamondback terrapins in Bermuda nest almost exclusively within a limited number of sand bunkers on the golf course. Nesting commenced in late March or early April and ended in late August. Peak oviposition was observed in May and June. Clutch size averaged 5.1 eggs (range 0-10; SD 2.4) and the incubation period averaged 61.8 days (range 49-83; SD 10.5). Delayed emergence was documented, with 43.8% of the hatchlings remaining in their natal nests over the winter months. The mean annual hatching success rate was determined to be 19% (range 17.6-21; SD 1.9). Radio-telemetry was used to investigate the movements and survivorship of postemergent hatchling diamondback terrapins. The results indicated that mangrove swamps and grass-dominated marshes adjacent to the ponds are important developmental habitats for hatchlings. Yellow-crowned night herons (Nyctanassa violacea) were found to be significant predators of small terrapins during spring emergence. Small aquatic gastropods comprised 66.7% of the faecal samples analysed from the Bermudian population. Scavenged fish and vertebrate animal remains, terrestrial arthropods, polychaete worms and bivalves were consumed in lesser amounts. Sediment from the pond environment was found in 74% of the faecal samples analysed and is believed to have been incidentally ingested while foraging for the small benthic gastropods. Eco-toxicological analyses of the pond sediment, prey and terrapin eggs showed that the Bermudian diamondback terrapins live and feed in wetland habitats characterised by chronic, multifactorial contamination; principally total petroleum hydrocarbons, polycyclic aromatic hydrocarbons and a variety of heavy metals. This study found that some of those contaminants are accumulating in the gastropod prey as well as being transferred to terrapin eggs. This may be reducing the incidence of successful embryonic development for this species in Bermuda and may likely contribute to the observed low hatching rates. These collective findings indicate that the Bermudian population is very vulnerable to local extirpation.

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The Quality of life is currently a major topic discussed in our society. The World Health Organization (WHO) has been developing a unifying and transcultural definition of QOL. They considered it as 'the individual's perception of his or her position in life, within the cultural context and value system he or she lives in, and in relation to his or her goals, expectations, parameters and social relations. It is a broad ranging concept affected in a complex way by the person's physical health, psychological state, level of independence, social relationships and their relationship to salient features of their environment (WHOQOL, 1997, p. 1). Congenital heart disease is the most prevalent congenital disease in Portugal. Despite the advances in cardiac treatment and an early correct diagnosis that could increase the survival of children with congenital heart disease, this condition influences the quality of life of children, adolescents and their parents. Knowing the perception of quality of life could help healthcare professionals, nurses in particular, providing suited care to the needs of these families, establishing priorities in their interventions, sensing predictors of a poor quality of life, promoting adherence to treatment and boosting compliance with treatment, and fostering greater satisfaction for these children, adolescents and their parents. Purpose As part of broader research and with the awareness that the chronic conditions could impact the quality of life and considering that all advances on treating congenital cardiac diseases we have defined this main objective: To determine the quality of life in children and adolescents with congenital heart disease (CHD) and the perception of their parents, as well as factors that influence it. Methods It is a quantitative, descriptive and correlational research. The data collection tool was a questionnaire, which consisted of four parts: socio-demographic and educational characteristics, clinical characteristics, and quality of life, obtained using the Pediatric Cardiac Quality of Life Inventory - PCQLI - (Marino, Tomlinson, Wernovsky, Drotar , Newburger, Mahony et al., 2010) translated into Portuguese. Data collection took place between February and July 2014, in compliance with ethical research guidelines. The sample comprised 59 children, 59 parents of children, 80 adolescents and 80 parents of adolescents. Results The results indicated that children, adolescents, and their parents have high level of perceived health. The results are similar in all groups: children and parents and adolescents and parents. In the group of children, we observed the classification of "Good" in 66.10%, followed by the "Very Good" at 18.65% and "fair" in 15.25% of cases. The parents of the children responded in about half the cases that the health of their children was "good" (50.85%), "very good" in 30.51% "fair" in 11.86% and "Excellent "in 6.78%. In turn, the group of adolescents can be seen that 46.25% rate their health as "good", 32.50% as "very good", 16.25% as "Average" and 5% as "Excellent". Parents of teenagers classify the health of their children mostly as "good" in 42.50%, 31.25% as "very good", 20% as "fair" and 6.25% as "excellent". To point out that none of the respondents pointed out the option of a health status "Bad". About the quality of life, in general the results indicated that children, adolescents and their parents have high levels of quality of life, and that perceptions of parents and children are similar. Only in the children's group (8 to 12 years old), was no influence of socio-demographic, school or clinical variables on quality of life observed. For adolescents (13 to 18 years old), school, special education, school retention, the age of diagnosis of congenital heart disease, cardiac catheterization and surgical intervention influenced their quality of life. Perception of quality of life of parents of children and of adolescents was influenced by socio-demographic and clinical variables. The results partly agree with the literature in this field. About the influence of some variables: - The perception of quality of life expressed by children and adolescents with congenital heart disease and parents are related, with statistical significance. - There were no statistically significant relationships between the quality of life of children and adolescents and their age, gender or socioeconomic status. - Adolescents differ statistically significant between their quality of life and their education, the frequency of special education and the existence of grade retention. The severity of heart disease, the number of cardiac catheterizations or surgery and the presence of other health disorders are unrelated to the quality of life of children and adolescents. - Adolescents revealed that the level of quality of life is influenced by the age of diagnosis of CHD by cardiac catheterization and surgery. - For parents of children and adolescents gender and their education don´t influence their perception of quality of life. Only the socioeconomic status of parents of teens has statistically significant difference to quality of life. - Parents of children and adolescents do not show statistically significant relationship between the perceived level of quality of life and severity of disease, age at diagnosis, the number of surgical interventions and the existence of other health disorders. - There is a relationship of statistical significance between cardiac catheterization and the perceived quality of life by parents of adolescents; between the number of cardiac catheterizations and the perception of quality of life of parents of children; and between performing surgery and the perception of parents of children and adolescents. Conclusion To analyze the quality of life of children and adolescents with CHD must be a key focus of attention in caring for this population, allowing the identification of individual differences, interests, preferences, and prevent potential problems. The knowledge acquired along with clinical experience contributes to improve the quality of life of children and families, facilitating their growth, psycho-emotional development and social integration. Nevertheless, the reading and interpretation of these results must be prudent and cautious, there are limitations to this research, including: the use of a range of specific quality of life for the Congenital heart disease in children, adolescents, and parents but whose validation process could not be completed in this study; the low prevalence of severe conditions in our sample; the absence of national studies to enable comparison with the results obtained. We intend to continue the process of validation of instrument and enlarge the research to Lisbon and Oporto, other major centers where the cardiac conditions can be treated

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Purpose: The Quality of life is currently a major topic discussed in our society. The World Health Organization (WHO) has been developing a unifying and transcultural definition of QOL. They considered it as 'the individual's perception of his or her position in life, within the cultural context and value system he or she lives in, and in relation to his or her goals, expectations, parameters and social relations. It is a broad ranging concept affected in a complex way by the person's physical health, psychological state, level of independence, social relationships and their relationship to salient features of their environment (WHOQOL, 1997, p. 1). Congenital heart disease is the most prevalent congenital disease in Portugal. Despite the advances in cardiac treatment and an early correct diagnosis that could increase the survival of children with congenital heart disease, this condition influences the quality of life of children, adolescents and their parents. Knowing the perception of quality of life could help healthcare professionals, nurses in particular, providing suited care to the needs of these families, establishing priorities in their interventions, sensing predictors of a poor quality of life, promoting adherence to treatment and boosting compliance with treatment, and fostering greater satisfaction for these children, adolescents and their parents. 'As part of broader research and with the awareness that the chronic conditions could impact the quality of life and considering that all advances on treating congenital cardiac diseases we have defined this main objective: To determine the quality of life in children and adolescents with congenital heart disease (CHD) and the perception of their parents, as well as factors that influence it. Methods: It is a quantitative, descriptive and correlational research. The data collection tool was a questionnaire, which consisted of four parts: socio-demographic and educational characteristics, clinical characteristics, and quality of life, obtained using the Pediatric Cardiac Quality of Life Inventory ? PCQLI - (Marino, Tomlinson, Wernovsky, Drotar , Newburger, Mahony et al., 2010) translated into Portuguese. Data collection took place between February and July 2014, in compliance with ethical research guidelines. The sample comprised 59 children, 59 parents of children, 80 adolescents and 80 parents of adolescents. Results: The results indicated that children, adolescents, and their parents have high level of perceived health. The results are similar in all groups: children and parents and adolescents and parents. In the group of children, we observed the classification of "Good" in 66.10%, followed by the "Very Good" at 18.65% and "fair" in 15.25% of cases. The parents of the children responded in about half the cases that the health of their children was "good" (50.85%), "very good" in 30.51% "fair" in 11.86% and "Excellent "in 6.78%. In turn, the group of adolescents can be seen that 46.25% rate their health as "good", 32.50% as "very good", 16.25% as "Average" and 5% as "Excellent". Parents of teenagers classify the health of their children mostly as "good" in 42.50%, 31.25% as "very good", 20% as "fair" and 6.25% as "excellent". To point out that none of the respondents pointed out the option of a health status "Bad". About the quality of life, in general the results indicated that children, adolescents and their parents have high levels of quality of life, and that perceptions of parents and children are similar. Only in the children?s group (8 to 12 years old), was no influence of socio-demographic, school or clinical variables on quality of life observed. For adolescents (13 to 18 years old), school, special education, school retention, the age of diagnosis of congenital heart disease, cardiac catheterization and surgical intervention influenced their quality of life. Perception of quality of life of parents of children and of adolescents was influenced by socio-demographic and clinical variables. The results partly agree with the literature in this field. About the influence of some variables: The perception of quality of life expressed by children and adolescents with congenital heart disease and parents are related, with statistical significance. There were no statistically significant relationships between the quality of life of children and adolescents and their age, gender or socioeconomic status. Adolescents differ statistically significant between their quality of life and their education, the frequency of special education and the existence of grade retention. The severity of heart disease, the number of cardiac catheterizations or surgery and the presence of other health disorders are unrelated to the quality of life of children and adolescents. Adolescents revealed that the level of quality of life is influenced by the age of diagnosis of CHD by cardiac catheterization and surgery. For parents of children and adolescents gender and their education don?t influence their perception of quality of life. Only the socioeconomic status of parents of teens has statistically significant difference to quality of life. Parents of children and adolescents do not show statistically significant relationship between the perceived level of quality of life and severity of disease, age at diagnosis, the number of surgical interventions and the existence of other health disorders. There is a relationship of statistical significance between cardiac catheterization and the perceived quality of life by parents of adolescents; between the number of cardiac catheterizations and the perception of quality of life of parents of children; and between performing surgery and the perception of parents of children and adolescents. Conclusion: To analyze the quality of life of children and adolescents with CHD must be a key focus of attention in caring for this population, allowing the identification of individual differences, interests, preferences, and prevent potential problems. The knowledge acquired along with clinical experience contributes to improve the quality of life of children and families, facilitating their growth, psycho-emotional development and social integration. Nevertheless, the reading and interpretation of these results must be prudent and cautious, there are limitations to this research, including: the use of a range of specific quality of life for the Congenital heart disease in children, adolescents, and parents but whose validation process could not be completed in this study; the low prevalence of severe conditions in our sample; the absence of national studies to enable comparison with the results obtained. We intend to continue the process of validation of instrument and enlarge the research to Lisbon and Oporto, other major centers where the cardiac conditions can be treated.

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The study of groundwater dependent ecosystems opened the opportunity to involve specialists of different areas of knowledge in order to obtain answers for complex interrelations between groundwater and the associated ecosystems. The actual study, carried out in two coastal lagoons of the Portuguese SW coast, showed the high dependency of the marine life and vegetation of the lagoons and associated streams discharging in the lagoons on the fresh water supply of these two lagoons and the high contribution they receive from groundwater in the dry period, which corresponds to more than half of each hydrologic year. Every year, the lagoons are artificially opened to the ocean for a few days to a few weeks, which dramatically changes the inside salinity. The sensitivity of these ecological niches is demonstrated by the strong dependence that some species that are more sensitive to high salinity waters show in relation to the entrance of freshwater resultant from the discharge of the phreatic aquifer of Sines sedimentary Basin. The great biodiversity of these lagoons and its precarious balance is only possible to preserve if the aquifer continue to act as a regulatory factor of the lagoon’s salinity. The equilibrium can be changed in the event of overexploitation of the phreatic aquifer, which is not at risk in the near future. In a scenario of climate change the lagoons will benefit from a slow increase in groundwater contribution, due to the rise of sea level, which will be accompanied by a rise in groundwater levels in the aquifer near the sea.

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The Charter of European Planning 2013 presents a Vision for the future of European cities and regions, highlighting the sustainability of cities and the preservation of urban ecosystems, integrating the man-made environment with the natural ecosystems and contribute to the well-being and quality of life of their inhabitants and other stakeholders. Thus, urban public policies are crucial to the improvement of the landscape ecological system, achievable by city planning and design. The paper aims to analyse if public urban policies in Portugal have been integrating strategies and/or guidelines to enhance the ecological system of the landscape. Then, which new perspectives are possible, framed by the recently approved law Bases of Public Policy of Soils, Land Management and Urban Planning (2014). This new law, in contrast with the previous ones, don’t allow reserving land to urbanize, in municipal master plans. Moreover, it is possible to revert land classified for urban purposes in those plans into rustic soils (when it is not yet infra-structured or built). It allows creating new planning and design dynamics, convert several areas and including them in the urban ecological structure, essential to the enhancement of landscape ecological system. This is a filed of work where landscape architecture has huge responsibilities, by associating and harmonize man-made environment with natural systems, enlightening sustainability consistent with conservation and improvement of Nature while contributing to the well-being and quality of life of Man. A sustainability that is ethical, aesthetic, ecological and cultural. The study is supported by a case study – the city of Évora. The ultimate goal is to propose measures to promote larger and better integration of ecological component in urban public policies, framed by the new territorial management law, taking into account and highlighting the specificities of the landscape system – Man and Nature – at the local level.

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OBJECTIVE: To evaluate the scored Patient-generated Subjective Global Assessment (PG-SGA) tool as an outcome measure in clinical nutrition practice and determine its association with quality of life (QoL). DESIGN: A prospective 4 week study assessing the nutritional status and QoL of ambulatory patients receiving radiation therapy to the head, neck, rectal or abdominal area. SETTING: Australian radiation oncology facilities. SUBJECTS: Sixty cancer patients aged 24-85 y. INTERVENTION: Scored PG-SGA questionnaire, subjective global assessment (SGA), QoL (EORTC QLQ-C30 version 3). RESULTS: According to SGA, 65.0% (39) of subjects were well-nourished, 28.3% (17) moderately or suspected of being malnourished and 6.7% (4) severely malnourished. PG-SGA score and global QoL were correlated (r=-0.66, P<0.001) at baseline. There was a decrease in nutritional status according to PG-SGA score (P<0.001) and SGA (P<0.001); and a decrease in global QoL (P<0.001) after 4 weeks of radiotherapy. There was a linear trend for change in PG-SGA score (P<0.001) and change in global QoL (P=0.003) between those patients who improved (5%) maintained (56.7%) or deteriorated (33.3%) in nutritional status according to SGA. There was a correlation between change in PG-SGA score and change in QoL after 4 weeks of radiotherapy (r=-0.55, P<0.001). Regression analysis determined that 26% of the variation of change in QoL was explained by change in PG-SGA (P=0.001). CONCLUSION: The scored PG-SGA is a nutrition assessment tool that identifies malnutrition in ambulatory oncology patients receiving radiotherapy and can be used to predict the magnitude of change in QoL.