986 resultados para Scenario
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PURPOSE: Spine surgery rates are increasing worldwide. Treatment failures are often attributed to poor patient selection and inappropriate treatment, but for many spinal disorders there is little consensus on the precise indications for surgery. With an aging population, more patients with lumbar degenerative spondylolisthesis (LDS) will present for surgery. The aim of this study was to develop criteria for the appropriateness of surgery in symptomatic LDS. METHODS: A systematic review was carried out to summarize the current level of evidence for the treatment of LDS. Clinical scenarios were generated comprising combinations of signs and symptoms in LDS and other relevant variables. Based on the systematic review and their own clinical experience, twelve multidisciplinary international experts rated each scenario on a 9-point scale (1 highly inappropriate, 9 highly appropriate) with respect to performing decompression only, fusion, and instrumented fusion. Surgery for each theoretical scenario was classified as appropriate, inappropriate, or uncertain based on the median ratings and disagreement in the ratings. RESULTS: 744 hypothetical scenarios were generated; overall, surgery (of some type) was rated appropriate in 27 %, uncertain in 41 % and inappropriate in 31 %. Frank panel disagreement was low (7 % scenarios). Face validity was shown by the logical relationship between each variable's subcategories and the appropriateness ratings, e.g., no/mild disability had a mean appropriateness rating of 2.3 ± 1.5, whereas the rating for moderate disability was 5.0 ± 1.6 and for severe disability, 6.6 ± 1.6. Similarly, the average rating for no/minimal neurological abnormality was 2.3 ± 1.5, increasing to 4.3 ± 2.4 for moderate and 5.9 ± 1.7 for severe abnormality. The three variables most likely (p < 0.0001) to be components of scenarios rated "appropriate" were: severe disability, no yellow flags, and severe neurological deficit. CONCLUSION: This is the first study to report criteria for determining candidacy for surgery in LDS developed by a multidisciplinary international panel using a validated method (RAM). The panel ratings followed logical clinical rationale, indicating good face validity. The work refines clinical classification and the phenotype of degenerative spondylolisthesis. The predictive validity of the criteria should be evaluated prospectively to examine whether patients treated "appropriately" have better clinical outcomes.
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The Culex pipiens complex includes two widespread mosquito vector species, Cx. pipiens and Cx. quinquefasciatus. The distribution of these species varies in latitude, with the former being present in temperate regions and the latter in tropical and subtropical regions. However, their distribution range overlaps in certain areas and interspecific hybridization has been documented. Genetic introgression between these species may have epidemiological repercussions for West Nile virus (WNV) transmission. Bayesian clustering analysis based on multilocus genotypes of 12 microsatellites was used to determine levels of hybridization between these two species in Macaronesian islands, the only contact zone described in West Africa. The distribution of the two species reflects both the islands’ biogeography and historical aspects of human colonization. Madeira Island displayed a homogenous population of Cx. pipiens, whereas Cape Verde showed a more intriguing scenario with extensive hybridization. In the islands of Brava and Santiago, only Cx. quinquefasciatus was found, while in Fogo and Maio high hybrid rates (~40%) between the two species were detected. Within the admixed populations, second-generation hybrids (~50%) were identified suggesting a lack of isolation mechanisms. The observed levels of hybridization may locally potentiate the transmission to humans of zoonotic arboviruses such as WNV.
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Abstract OBJECTIVE To identify, in the perception of nurses, the factors that affect the quality of cardiopulmonary resuscitation (CPR) in adult inpatient units, and investigate the influence of both work shifts and professional experience length of time in the perception of these factors. METHOD A descriptive, exploratory study conducted at a hospital specialized in cardiology and pneumology with the application of a questionnaire to 49 nurses working in inpatient units. RESULTS The majority of nurses reported that the high number of professionals in the scenario (75.5%), the lack of harmony (77.6%) or stress of any member of staff (67.3%), lack of material and/or equipment failure (57.1%), lack of familiarity with the emergency trolleys (98.0%) and presence of family members at the beginning of the cardiopulmonary arrest assistance (57.1%) are factors that adversely affect the quality of care provided during CPR. Professional experience length of time and the shift of nurses did not influence the perception of these factors. CONCLUSION The identification of factors that affect the quality of CPR in the perception of nurses serves as parameter to implement improvements and training of the staff working in inpatient units.
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We provide estimates of the costs associated with inducing substantial conversion of land from production of traditional crops to switchgrass. Higher traditional crop prices due to increased demand for corn from the ethanol industry has increased the relative advantage that row crops have over switchgrass. Results indicate that farmers will convert to switchgrass production only with significant conversion subsidies. To examine potential environmental consequences of conversion, we investigate three stylized landscape usage scenarios, one with an entire conversion of a watershed to switchgrass production, a second with the entire watershed planted to continuous corn under a 50% removal rate of the biomass, and a third scenario that places switchgrass on the most erodible land in the watershed and places continuous corn on the least erodible. For each of these illustrative scenarios, the watershed-scale Soil and Water Assessment Tool (SWAT) hydrological model (Arnold et al., 1998; Arnold and Forher, 2005) is used to evaluate the effect of these landscape uses on sediment and nutrient loadings in the Maquoketa Watershed in eastern Iowa.
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Projections of U.S. ethanol production and its impacts on planted acreage, crop prices, livestock production and prices, trade, and retail food costs are presented under the assumption that current tax credits and trade policies are maintained. The projections were made using a multi-product, multi-country deterministic partial equilibrium model. The impacts of higher oil prices, a drought combined with an ethanol mandate, and removal of land from the Conservation Reserve Program (CRP) relative to baseline projections are also presented. The results indicate that expanded U.S. ethanol production will cause long-run crop prices to increase. In response to higher feed costs, livestock farmgate prices will increase enough to cover the feed cost increases. Retail meat, egg, and dairy prices will also increase. If oil prices are permanently $10-per-barrel higher than assumed in the baseline projections, U.S. ethanol will expand significantly. The magnitude of the expansion will depend on the future makeup of the U.S. automobile fleet. If sufficient demand for E-85 from flex-fuel vehicles is available, corn-based ethanol production is projected to increase to over 30 billion gallons per year with the higher oil prices. The direct effect of higher feed costs is that U.S. food prices would increase by a minimum of 1.1% over baseline levels. Results of a model of a 1988-type drought combined with a large mandate for continued ethanol production show sharply higher crop prices, a drop in livestock production, and higher food prices. Corn exports would drop significantly, and feed costs would rise. Wheat feed use would rise sharply. Taking additional land out of the CRP would lower crop prices in the short run. But because long-run corn prices are determined by ethanol prices and not by corn acreage, the long-run impacts on commodity prices and food prices of a smaller CRP are modest. Cellulosic ethanol from switchgrass and biodiesel from soybeans do not become economically viable in the Corn Belt under any of the scenarios. This is so because high energy costs that increase the prices of biodiesel and switchgrass ethanol also increase the price of cornbased ethanol. So long as producers can choose between soybeans for biodiesel, switchgrass for ethanol, and corn for ethanol, they will choose to grow corn. Cellulosic ethanol from corn stover does not enter into any scenario because of the high cost of collecting and transporting corn stover over the large distances required to supply a commercial-sized ethanol facility.
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This work, dedicated to the study of nesting habits of the species of the Neotropical genus Partamona Schwarz, is a sequence to the taxonomic revision recently published elsewhere. A total of 214 nests and nest aggregations of 18 species [Partamona epiphytophila Pedro & Camargo, 2003; P. testacea (Klug, 1807); P. mourei Camargo, 1980; P. vicina Camargo, 1980; P. auripennis Pedro & Camargo, 2003; P. combinata Pedro & Camargo, 2003; P. chapadicola Pedro & Camargo, 2003; P. nhambiquara Pedro & Camargo, 2003; P. ferreirai Pedro & Camargo, 2003; P. pearsoni (Schwarz, 1938); P. gregaria Pedro & Camargo, 2003; P. batesi Pedro & Camargo, 2003; P. ailyae Camargo, 1980; P. cupira (Smith, 1863); P. mulata Moure in Camargo, 1980; P. seridoensis Pedro & Camargo, 2003; P. criptica Pedro & Camargo, 2003; P. helleri (Friese, 1900)] were studied , including data about habitat, substrate, structural characteristics, construction materials and behavior. The descriptions of the nests are illustrated with 48 drawings. Partial data of the nests of P. bilineata (Say, 1837), P. xanthogastra Pedro & Camargo, 1997, P. orizabaensis (Strand, 1919), P. peckolti (Friese, 1901), P. aequatoriana Camargo, 1980, P. musarum (Cockerell, 1917) and P. rustica Pedro & Camargo, 2003 are also presented. Nests of P. grandipennis (Schwarz, 1951), P. yungarum Pedro & Camargo, 2003, P. subtilis Pedro & Camargo, 2003, P. vitae Pedro & Camargo, 2003, P. nigrior (Cockerell, 1925), P. sooretamae Pedro & Camargo, 2003 and P. littoralis Pedro & Camargo, 2003 are unknown. The species of Partamona build notable nest entrance structures, with special surfaces for incoming / exiting bees; some of them are extremely well-elaborated and ornamented, serving as flight orientation targets. All species endemic to western Ecuador to Mexico with known nesting habits (P. orizabaensis, P. peckolti, P. xanthogastra, P. bilineata, P. aequatoriana and P. musarum) build their nests in several substrates, non-associated with termitaria, such as cavities and crevices in walls, among roots of epiphytes and in bases of palm leaves, in abandoned bird nests, under bridges, and in other protected places, except P. peckolti that occasionally occupies termite nests. In South America, on the eastern side of the Andes, only P. epiphytophila and P. helleri nest among roots of epiphytes and other substrates, non-associated with termitaria. All other species studied (P. batesi, P. gregaria, P. pearsoni, P. ferreirai, P. chapadicola, P. nhambiquara, P. vicina, P. mourei, P. auripennis, P. combinata, P. cupira, P. mulata, P. ailyae, P. seridoensis, P. criptica and P. rustica) nest inside active termite nests, whether epigeous or arboreous. The only species that builds obligate subterranean nests, associated or not with termite or ant nests (Atta spp.) is P. testacea. Nests of Partamona have one vestibular chamber (autapomorphic for the genus) closely adjacent to the entrance, filled with a labyrinth of anastomosing pillars and connectives, made of earth and resins. One principal chamber exists for food and brood, but in some species one or more additional chambers are filled with food storage pots. In nests of P. vicina, there is one atrium or "false nest", between the vestibule and the brood chamber, which contains involucral sheaths, cells and empty pots. All structures of the nest are supported by permanent pillars made of earth and resins (another autapomorphy of the genus). The characters concerning nesting habits were coded and combined with morphological and biogeographic data, in order to hypothesize the evolutive scenario of the genus using cladistic methodology. The phylogenetic hypothesis presented is the following: (((((P. bilineata (P. grandipennis, P. xanthogastra)) (P. orizabaensis, P. peckolti)) (P. aequatoriana, P. musarum)) P. epiphytophila, P. yungarum, P. subtilis, P. vitae) (((((P. testacea (P. mourei, P. vicina)) (P. nigrior (P. auripennis, P. combinata))) (P. ferreirai (P. pearsoni (P. gregaria (P. batesi (P. chapadicola, P. nhambiquara)))))) ((((P. ailyae, P. sooretamae) P. cupira, P. mulata) P. seridoensis) P. criptica, P. rustica, P. littoralis)) P. helleri))). One area cladogram is presented. Dates of some vicariance / cladogenesis events are suggested. For bilineata / epiphytophila group, which inhabits the Southwestern Amazonia and the Chocó-Mexican biogeographical components, the origin of ancestral species is attributed to the Middle Miocene, when the transgressions of the Maracaibo and Paranense seas isolated the tropical northwestern South America from the eastern continental land mass. The next cladogenic event in the history of the bilineata / epiphytophila group is attributed to the Plio-Pleistocene, when the Ecuadorian Andes reached more than 3000 m, and the ancestral species was fragmented in two populations, one occupying the western Andes (ancestral species of the bilineata subgroup) and other the southwestern Amazon (ancestral species of the epiphytophila subgroup). Other aspects of the history of Partamona are also discussed.
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The forensic two-trace problem is a perplexing inference problem introduced by Evett (J Forensic Sci Soc 27:375-381, 1987). Different possible ways of wording the competing pair of propositions (i.e., one proposition advanced by the prosecution and one proposition advanced by the defence) led to different quantifications of the value of the evidence (Meester and Sjerps in Biometrics 59:727-732, 2003). Here, we re-examine this scenario with the aim of clarifying the interrelationships that exist between the different solutions, and in this way, produce a global vision of the problem. We propose to investigate the different expressions for evaluating the value of the evidence by using a graphical approach, i.e. Bayesian networks, to model the rationale behind each of the proposed solutions and the assumptions made on the unknown parameters in this problem.
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The problems arising in the logistics of commercial distribution are complexand involve several players and decision levels. One important decision isrelated with the design of the routes to distribute the products, in anefficient and inexpensive way.This article explores three different distribution strategies: the firststrategy corresponds to the classical vehicle routing problem; the second isa master route strategy with daily adaptations and the third is a strategythat takes into account the cross-functional planning through amulti-objective model with two objectives. All strategies are analyzed ina multi-period scenario. A metaheuristic based on the Iteratetd Local Search,is used to solve the models related with each strategy. A computationalexperiment is performed to evaluate the three strategies with respect to thetwo objectives. The cross functional planning strategy leads to solutions thatput in practice the coordination between functional areas and better meetbusiness objectives.
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The current context of a strong competition and the ongoing search for competitive advantages requires more than processes modernization, technological and financial resources. It requires a competent workforce, strongly committed and engaged with Organization’s challenges. Under this scenario, it seems crucial to synchronize their performance with Organization’s strategy, aimed at pursuing its effective achievement. If well used, the Performance Evaluation as a strategy for Human Resource Management presents itself as an instrument to foster high levels of performance. A more recent approach of this policy refers to Performance Management representing a dynamic and participative evaluation system, which combines the development of consensual goals, support and follow-up for further execution of respective assessment. This research was based on the ENAPOR, S.A (Porto da Praia) case, with the intention of checking the alignment of its Performance Evaluation System with the Company's strategic goals and what the process features.
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In the last 50 years, concern about the loss of lichen diversity associated with forest management and forest fragmentation has led to many studies designed to assess patterns and monitor trends of lichen biodiversity in forests worldwide. However there are surprisingly few studies focusing on the effect of natural disturbance for epiphytic lichens in forest ecosystems and, especially, on how these changes affect the relationships between epiphytic lichens and other organisms. The major goal of this thesis was to characterize and valuate the epiphytic lichens in the Baixo Tamega region (northern Portugal) and to assess its vulnerability to several drivers of change, particularly fire. The study area is located in Aboboreira and Castelo, a mountain area with 105 km2 and a top altitude of approximately 1000 m.a.s.l. In this region, fire is one of the worst natural catastrophes not only because of its high frequency and wide extension but also because of their enormous destructive effects. This thesis has included three case studies that proved the need to develop management and conservation actions for the area. In the first study we assessed the epiphytic lichen diversity in the oak woods of the Aboboreira and Castelo mountains. Results have revealed high diversity value and presence of a lichen community that has suffered general decline throughout Europe. The second study has addressed the impact of fire over epiphytic lichens and community recovering patterns. Results observed along the fire gradient showed that the most common and abundant lichen species establish themselves early in post-fire gradient while “old-growth” associated lichens tend to recover slowly along the same gradient. The third study intended to evaluate the potential use of selected lichen species or groups as biodiversity surrogates, in a scenario of fire-controlled ecological changes. Results showed that the use of epiphytic lichens as surrogates of bryophyte and vascular plant diversity should consider not only species richeness and composition, but also occurrence of disturbing factors, such fire. among the studied groups, lichen genera is the only group that can be used as surrogate of total epiphytic lichen diversity, independently of fire induced changes
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The work by Koglin et al. (Koglin, N., Kostopoulos, D., Reichmann, T., 2009. Geochemistry, petrogenesis and tectonic setting of the Samothraki mafic Suite, NE Greece: Trace-element, isotopic and zircon age constraints. Tectonophysics 473, 53-68. doi: 10.1016/j.tecto.2008.10.028), where the authors have proposed to nullify the scenario presented by Bonev and Stampfli (Bonev, N., Stampfli, G., 2008. Petrology, geochemistry and geodynamic implications of Jurassic island arc magmatism as revealed by mafic volcanic rocks in the Mesozoic low-grade sequence, eastern Rhodope, Bulgaria. Lithos 100, 210-233) is here Put under discussion. The arguments for this proposal are reviewed in the light of available stratigraphic and radiometric age constraints, geochemical signature and tectonics of highly relevant Jurassic ophiolitic suites occurring immediately north of the Samothraki mafic suite. Our conclusion is that the weak arguments and the lack of knowledge on the relevant constraints from the regional geologic information make inconsistent the Proposal and the model of these authors. (C) 2009 Elsevier B.V. All rights reserved.
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Although evidence is accumulating that mothers can transfer antibodies to their offspring, little is known about the consequences of such a transfer to the offspring immune system. Because maternal antibodies are effective only during a short period of time after their transfer to offspring, one hypothesis is that maternal antibodies provides a transitory antigen-specific protection to offspring, thus lessening the need for offspring to mount their own humoral immune response towards these specific antigens. In birds, this scenario predicts that offspring immune response towards a specific antigen is inhibited to a larger extent in hatchlings than in older nestlings. We tested this hypothesis in tawny owls Strix aluco by cross-fostering clutches between nests and then challenging siblings with a vaccine either two times (at 4- and 11-d-old) or only one time at 11-d-old to compare the strength of the humoral response between nestlings born from mothers with naturally high and low levels of antibodies against this vaccine. Because maternal antibodies are expected to be effective only during a short period of time after hatching, we predict that maternal antibodies should inhibit the immune response of nestlings vaccinated from the fourth day after hatching more than in nestlings vaccinated only at a later age. As expected, the inhibitory effect of maternal antibodies was stronger in nestlings vaccinated soon after hatching than in siblings injected at a later age. Therefore, in wild avian populations pre-hatching maternal effects may confer offspring with a transitory immune protection in the first days following hatching.
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This preliminary exploration was limited by a number of factors. The format of the study has necessarily induced some form of selection bias of the panelists, because of the complexity of some questions, and the time required to complete the questionnaires. Several issues have not been addressed. One example could be the response to HIV infection occurring in a vaccinee. The study also did not address the difficulties related to the licensing of the vaccine. Indeed, the proposed scenario assumed that the vaccine had been registered as a starting point for the analysis. Finally, it has not been possible to conduct a sensitivity analysis, in order to evaluate how the responses would have been modified if some important characteristics of the vaccine had been modified.Very diverse evaluations were given in response to questions related with attitudes and perception of AIDS and AIDS vaccine. The possibility that vaccine availability or usage can be associated with an increased frequency in risky behaviors was spontaneously mentioned by half of the panelists. The estimation of the proportion of persons at highest risk who would choose to use this vaccine also indicated a high degree of uncertainty. This study offers important lessons. According to a broad and diverse panel of individuals, an incompletely effective AIDS vaccine would result in an additional level of complexity for the AIDS prevention strategy, rather than a simplification. The use of such a vaccine would have to be coupled with counselling. This implies a sustained emphasis on the recommendations which have been central to the STOP AIDS campaigns until now. In addition, consensual issues, as well as other issues more likely to be controversial have been identified. This should greatly help focusing the work of any committee designated to develop and implement a vaccination policy if an AIDS vaccine became available. Finally, our experience with the Policy Delphi indicates that this mode of structured communication could be usefully applied to other public health issues presenting a high visibility as well as a complex relationship with public perception.
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Pela sua posição geográfica e particulares condições climáticas, devidas à sua inserção na faixa saheliana com caraterísticas de marcada aridez, Cabo Verde é um arquipélago com condições naturais adversas, pautado principalmente pela seca prolongada. Muitas vezes esta conjuntura é interpolada por curtos períodos de fortes chuvadas que podem originar cheias e inundações nos principais centros urbanos. Os eventos ocorridos revelam consequências graves, desde prejuízos na agricultura, perda de animais, destruição de infra-estruturas, perda de bens materiais e, mesmo, vítimas humanas mortais. Este estudo tem como objetivos principais: (i) perceber os problemas e desafios que se colocam à cidade da Praia (maior centro urbano do país, com forte crescimento e expansão urbana) perante situações de inundação; (ii) contribuir para o maior conhecimento das causas e consequências dessas inundações; (iii) definir quais as áreas de maior suscetibilidade às cheias e quais as que possuem um maior risco potencial. Optou-se por uma metodologia integrada, através do levantamento bibliográfico, cartográfico, numérico e percetivo (com base em entrevistas e inquéritos). Para o estudo das bacias hidrográficas foram calculados índices morfométricos, definidas classes de permeabilidade do substrato geológico e aplicado o método multicritério de Reis (2011) para a definição das áreas suscetíveis às cheias. Analisaram-se as precipitações máximas diárias anuais e respetivos períodos de retorno, com a aplicação do método de Gumbel. A análise de notícias de jornais, referentes ao período compreendido entre 1980 e 2011, foi fundamental para o conhecimento da distribuição espácio-temporal dos eventos perigosos de inundação em Cabo Verde e na cidade da Praia. Os resultados obtidos revelam um significativo grau de suscetibilidade às cheias na cidade da Praia. As áreas de maior risco potencial às inundações encontram-se no setor central da cidade, resultante da conjugação da convergência do escoamento das três ribeiras principais, da elevada densidade populacional e de construção desordenada nos leitos de cheia e nas áreas deprimidas, onde se acumulam as águas.
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O impacto das espécies exóticas e a sua acção nociva sobre a flora nativa torna-se especialmente preocupante em ecossistemas insulares degradados. Tendo em conta a preservação e conservação da biodiversidade das ilhas de Cabo Verde pretende-se com este estudo avaliar o impacto que algumas espécies exóticas exercem sobre os ecossistemas naturais, tendo como modelo de estudo a maior ilha do arquipélago, a ilha de Santiago. Faz-se inicialmente uma breve caracterização da flora exótica do arquipélago, estimada em 397 taxa, tendo em conta o tipo biológico, origem biogeográfica, tipo de utilização, distribuição pelas ilhas e ecologia. Com o objectivo de melhor compreender como a distribuição das espécies exóticas pode evoluir na ilha de Santiago, procedeu-se à modelação de quatro espécies com características invasoras (Bidens bipinnata, Euphorbia heterophylla, Furcraea foetida e Lantana camara) usando metodologias de regressão logística. Os modelos produzidos permitiram a produção de mapas de probabilidade de ocorrência das espécies em estudo, utilizando para isso sistemas de informação geográfica. A aplicação destes métodos permitiu por um lado conhecer algumas das variáveis que afectam a distribuição das espécies exóticas (e.g. precipitação; NDVI; exposição NE; distância às ribeiras; altitude), e por outro lado, produzir mapas da ilha de Santiago, que permitiram revelar quais as zonas com maior probabilidade de ocorrência dessas espécies. Os nossos resultados indicam que as zonas de altitude (e.g. Serra do Pico da Antónia; Monte Graciosa; Serra da Malagueta) são especialmente vulneráveis à ocorrência de espécies invasoras, o que se torna particularmente preocupante pois correspondem a zonas demarcadas como áreas protegidas, sendo locais primordiais de distribuição para a flora endémica do arquipélago. Por fim, sugerem-se algumas medidas de gestão e controlo de espécies invasoras de modo a que a sua implementação permita que num futuro, que se espera próximo, recuperar estes ecossistemas insulares que se encontram muito degradados.