976 resultados para Determinant factors
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No dia a dia de uma equipa, muitos são os fatores que influenciam o seu funcionamento e a sua construção. Uma constante adaptação ao contexto envolvente e à evolução em termos de conhecimento científico, são fatores determinantes no trabalho de um treinador. Desta forma, possuindo mais e melhores ferramentas de trabalho, permitir-lhe-á maximizar a aprendizagem e o rendimento dos seus jogadores. Neste relatório, pretende-se apresentar, analisar e refletir sobre a conceção e implementação das atividades práticas durante toda a época desportiva da equipa de Juniores do Grupo Desportivo Alcochetense, Para além da parte ligada às várias áreas do treino, este relatório irá abranger outras áreas de grande importância na vida de um treinador, sendo elas a área de Inovação e Investigação (Área 2) e a Relação com a Comunidade (Área 3). Com base na análise do contexto e nos objetivos definidos para a equipa, descrevemos e fundamentamos o modelo de jogo criado pela equipa técnica, assim como o planeamento definido para a época desportiva. Através de uma categorização dos exercícios de treino, foi possível fazer uma quantificação do volume de treino de cada categoria, o que permitiu perceber quais os conteúdos mais abordados durante toda a época desportiva. Na área 2 do estágio, procuramos aprofundar o conhecimento em torno da inclusão do trabalho físico complementar como meio de prevenção de lesões no processo de treino de uma equipa de futebol e a relação que este pode ter no desempenho desportivo. Embora não tenha sido possível proceder à sua aplicação prática, parece clara a importância deste tipo de abordagem no treino de uma equipa de futebol. Como tal, apresentamos uma proposta de protocolo de treino de prevenção de lesões. No âmbito da área 3, partindo da necessidade da comunidade de treinadores de futebol em manter uma formação teórica continua, foram organizadas duas ações de formação, em parceria com o Núcleo de Lisboa da Associação Nacional de Treinadores de Futebol, sobre a temática da Organização Estrutural do Exercício em Futebol e sobre as Bases para a construção de uma equipa de Futebol.
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El presente estudio analiza las percepciones y actitudes que tienen los adultos mayores de la ciudad de Cuenca, Ecuador hacia el aprendizaje del inglés. Un total de 151 adultos mayores (con edad promedio de 70.3 años) respondió a un cuestionario con 50 ítems. Se llevó a cabo análisis factoriales, de regresión múltiple y cluster con el propósito de definir las dimensiones subyacentes en las percepciones, motivaciones y ambiciones de los adultos mayores para aprender un idioma extranjero, y su relación con las características sociodemográficas de los participantes. Los resultados señalan que el interés por estudiar un idioma extranjero está basado en la percepción de que aquello mejora la interacción social de las personas, su desarrollo personal, el funcionamiento y mantenimiento de la mente y memoria, y que activa y vuelve su vida más dinámica. Los resultados además revelaron que la principal motivación de los participantes para tomar un curso de inglés está relacionada con el potencial de usar este idioma en la vida diaria y el de leer profusamente en esa lengua extranjera. La duración del curso y la obtención de un certificado fueron factores determinantes que permitieron agrupar a los participantes en función de sus preferencias en lo que respecta al diseño práctico de un curso de inglés. Adicionalmente, la edad y el nivel de instrucción fueron variables determinantes de motivación que influyeron en la mayor parte de las respuestas dadas por los participantes.
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Tourist accommodation expenditure is a widely investigated topic as it represents a major contribution to the total tourist expenditure. The identification of the determinant factors is commonly based on supply-driven applications while little research has been made on important travel characteristics. This paper proposes a demand-driven analysis of tourist accommodation price by focusing on data generated from room bookings. The investigation focuses on modeling the relationship between key travel characteristics and the price paid to book the accommodation. To accommodate the distributional characteristics of the expenditure variable, the analysis is based on the estimation of a quantile regression model. The findings support the econometric approach used and enable the elaboration of relevant managerial implications.
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Esta investigação visa averiguar quais as práticas educativas dos pais para apoiar a aprendizagem dos seus filhos. A investigação é enquadrada pelo marco sociocognitivo da auto-regulação da aprendizagem (Bandura, 1997; Rosário, 2004; Schunk, 2001; Zimmerman, 2000). A amostra foi constituída por 30 encarregados de educação com filhos a frequentar o 4°ano de escolaridade do ensino básico, numa escola pública localizada no distrito de Lisboa. Os dados foram obtidos através de questionários de resposta aberta, tendo sido utilizados procedimentos qualitativos e quantitativos na sua análise e tratamento. Os resultados revelam que os pais consideram maioritariamente que aprender e estudar são algo que se diferencia. Os factores determinantes sobre quem dá suporte e apoio ao aprender da criança prendem-se sobretudo com a disponibilidade e com o conhecimento por parte do progenitor em causa. Os pais criam condições físicas e ambientais para o apoio ao estudo o qual é sobretudo feito através da realização dos TPC e acreditam que o apoio por si prestado é vantajoso. As estratégias mais utilizadas pelos pais são as de ensaio e monitorização. /ABSTRACT: This investigation's purpose is to inquire what strategies are being used by parents in learning support. The investigation is of quality kind, and it's based on the sociocognitive theory (Bandura, 1997; Rosário, 2004; Schunk, 2001; Zimmerman, 2000) of self-regulated learning. ln this study participated 30 parents whose children are forth grade students, in a public school located in the district of Lisbon. Ali the data was obtained through an openanswer questionnaire and qualitative and quantitative procedures were used in its study and analysis. The results attained reveal that parents consider studying to be something different from learning. The determinant factors on who provides children's learning support are mostly related with the availability and the knowledge of the ancestor in cause. Parents create physical and ambient conditions for study support which over all is made through the accomplishment of homework and believe that the support given from themselves has advantageous. The strategies most commonly used by parents are of rehearsal and monitoring.
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This study aims to analyse the extent of online social responsibility (SR) information disclosure by Portuguese municipalities and to identify related determinant factors, based on Institutional Theory and Legitimacy Theories. A content analysis was performed on webpages from 60 sampled municipalities, and an information disclosure index was created.Descriptive statistics obtained indicate the Total Disclosure Index (TDI) value was 0.46. The Economic Information sub-category exhibits the highest value (0.66), followed by the Social and Environmental Information categories (0.61 and 0.36, respectively). The multivariate analysis results indicate that LA21 implementation the existence of tax burdens, the characterisation of a municipality as urban and environmental/SR certification application positively influence SR information disclosure. TDI is negatively affected by the existence of an inactive population (i.e. by the percentage of individuals ≤19 and ≥65 years of age).
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Fish assemblages in seagrass and unvegetated habitats located in shallow intertidal creeks within the saltmarsh area of the Ria Formosa coastal lagoon were sampled with a Riley push net at 3 sites on a monthly basis over a 1 yr period. The objective was to test if both habitats support similar fish assemblages in terms of abundance, diversity, assemblage structure, and size distribution, and to investigate how site and season affect the assemblages. Fish assemblages associated with these habitats were significantly different in terms of diversity, abundance, and assemblage structure. Seagrass supported a larger number of species and greater diversity, while unvegetated habitat supported greater fish numbers but only of a few species. The habitats were dominated by different groups of resident species that were responsible for major differences in fish assemblage structure between habitats. Pomatoschistus microps and young-of-the-year (YOY) Atherina presbyter dominated the unvegetated habitat, while seagrass was dominated by a diverse group of species, in particular syngnathids and small labrids, revealing different habitat preferences. Site and season were determinant factors conditioning the role of habitat in structuring fish assemblages. Distance between habitats, site elevation, and the amount of marsh drained affected fish assemblages in both habitats. Seasonal fluctuations in the presence and abundance of YOY from marine migrant and resident species were responsible for comparable changes in fish assemblage structure in both habitats. Both habitats provide a distinctive nursery area for different species, while common species reveal ontogenic distributional changes between habitats, where smaller fish appear first in unvegetated creeks.
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Objetivo: analizar cómo influye la inequidad y la posición socio económica como factores determinantes de la conceptualización de la actividad física, desde la concepción de los determinantes sociales, de forma tal que su revisión conceptual, ayude a constituir la re configuración del concepto de actividad física. Métodos: Exploración de la literatura científica desde la revisión conceptual de artículos seleccionados, utilizando las categorías inequidad y posición socioeconómica para establecer la influencia del concepto de la actividad física en entornos educativos. Y a partir de ella interpretar la re configuración del concepto de la actividad física, desde diferentes concepciones asociadas a los determinantes sociales. Resultados: Se hallaron concepciones de los diferentes autores respecto al concepto de la actividad física. (Peso, raza, índice de masa corporal, edad). Se interpretaron distintos niveles de influencia desde la inequidad y la posición socio económica asociados a la ocupación, el género, sitio de vivienda, nivel de estudio, y la estructura física del entorno. Posteriormente se reportaron resultados desde un análisis explicativo en el cual se interpretan las concepciones de los autores en cuanto al concepto de la actividad física, y como desde ella se establecen relaciones entre la inequidad, la posición socioeconómica y los entornos educativos que incluyen diferentes aspectos sociales para finalmente poder establecer un concepto claro de la re configuración social del concepto de la actividad física, concluyendo que este nuevo concepto social de la actividad física no posee una definición exacta, el análisis de los aspectos sociales de ésta, involucra innumerables concepciones que la influencian y la determinan, en consecuencia el concepto de la actividad física debe ser un concepto en constante evolución y reconfiguración debido a la naturaleza cambiante del ser humano, de las dinámicas sociales y las asociaciones de la salud con los aspectos sociales que se presentan en el diario vivir. Así mismo se evidencia que el concepto de la actividad física se fundamenta en estudios que dejan de lado los aspectos sociales que influencia el concepto y en consecuencia la práctica de la actividad física, esta investigación establece un punto de partida frente a la re configuración social del concepto de la actividad física. Conclusiones: Diferentes organizaciones en el mundo reconocen a la actividad física como una herramienta que favorece la socialización de las personas. Es así como la actividad física, desde el deporte en el campo competitivo y la educación física desde el campo educativo exploran la interacción social de los individuos, esto permite la construcción de valores y fortalece la sana convivencia dentro de las comunidades. Esta trasformación desde el concepto de la actividad física biomédica hasta la actividad física social se evidencia en los documentos revisados, en los cuales la actividad física es estudiada desde las categorías de inequidad y posición socio económica, De ahí que en su conceptualización se involucren diferentes conceptos asociados a los determinantes sociales de la salud, que en definitiva establecen un nuevo concepto de la re configuración social de la actividad física trascendiendo desde la actividad física biomédica o fisiológica hasta un concepto complejo que incluye intereses y particularidades de las personas como lo son la ocupación, la educación, el entorno, el medio ambiente y la estructura física.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Background: Information on infant and young child feeding is widely available in Demographic and Health Surveys and National Family Health Surveys for countries in South Asia; however, infant and young child feeding indicators from these surveys have not been compared between countries in the region. Objective. To compare the key indicators of breastfeeding and complementary feeding and their determinants in children under 24 months of age between four South Asian countries. Methods: We selected data sets from the Bangladesh Demographic and Health Survey 2004, the India National Family Health Survey (NFHS-03) 2005–06, the Nepal Demographic and Health Survey 2006, and the Sri Lanka 2000 Demographic and Health Survey. Infant feeding indicators were estimated according to the key World Health Organization indicators. Results: Exclusive breastfeeding rates were 42.5% in Bangladesh, 46.4% in India, and 53.1% in Nepal. The rate of full breastfeeding ranged between 60.6% and 73.9%. There were no factors consistently associated with the rate of no exclusive breastfeeding across countries. Utilization of health services (more antenatal clinic visits) was associated with higher rates of exclusive breastfeeding in India but lower rates in Nepal. Delivery at a health facility was a negative determinant of exclusive breastfeeding in India. Postnatal contacts by Public Health Midwives were a positive factor in Sri Lanka. A considerable proportion of infants under 6 months of age had been given plain water, juices, or other nonmilk liquids. The rate of timely first suckling ranged from 23.5% in India to 56.3% in Sri Lanka. Delivery by cesarean section was found to be a consistent negative factor that delayed initiation of breastfeeding. Nepal reported the lowest bottle-feeding rate of 3.5%. Socioeconomically privileged mothers were found to have higher bottlefeeding rates in most countries. Conclusions: Infant and young child feeding practices in the South Asia region have not reached the expected levels that are required to achieve a substantial reduction in child mortality. The countries with lower rates of exclusive breastfeeding have a great potential to improve the rates by preventing infants from receiving water and water-based or other nonmilk liquids during the first 6 months of life.
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In developed countries the relationship between socioeconomic position (SEP) and health is unequivocal. Those who are socioeconomically disadvantaged are known to experience higher morbidity and mortality from a range of chronic diet-related conditions compared to those of higher SEP. Socioeconomic inequalities in diet are well established. Compared to their more advantaged counterparts, those of low SEP are consistently found to consume diets less consistent with dietary guidelines (i.e. higher in fat, salt and sugar and lower in fibre, fruit and vegetables). Although the reasons for dietary inequalities remain unclear, understanding how such differences arise is important for the development of strategies to reduce health inequalities. Both environmental (e.g. proximity of supermarkets, price, and availability of foods) and psychosocial (e.g. taste preference, nutrition knowledge) influences are proposed to account for inequalities in food choices. Although in the United States (US), United Kingdom (UK), and parts of Australia, environmental factors are associated with socioeconomic differences in food choices, these factors do not completely account for the observed inequalities. Internationally, this context has prompted calls for further exploration of the role of psychological and social factors in relation to inequalities in food choices. It is this task that forms the primary goal of this PhD research. In the small body of research examining the contribution of psychosocial factors to inequalities in food choices, studies have focussed on food cost concerns, nutrition knowledge or health concerns. These factors are generally found to be influential. However, since a range of psychosocial factors are known determinants of food choices in the general population, it is likely that a range of factors also contribute to inequalities in food choices. Identification of additional psychosocial factors of relevance to inequalities in food choices would provide new opportunities for health promotion, including the adaption of existing strategies. The methodological features of previous research have also hindered the advancement of knowledge in this area and a lack of qualitative studies has resulted in a dearth of descriptive information on this topic. This PhD investigation extends previous research by assessing a range of psychosocial factors in relation to inequalities in food choices using both quantitative and qualitative techniques. Secondary data analyses were undertaken using data obtained from two Brisbane-based studies, the Brisbane Food Study (N=1003, conducted in 2000), and the Sixty Families Study (N=60, conducted in 1998). Both studies involved main household food purchasers completing an interviewer-administered survey within their own home. Data pertaining to food-purchasing, and psychosocial, socioeconomic and demographic characteristics were collected in each study. The mutual goals of both the qualitative and quantitative phases of this investigation were to assess socioeconomic differences in food purchasing and to identify psychosocial factors relevant to any observed differences. The quantitative methods then additionally considered whether the associations examined differed according to the socioeconomic indicator used (i.e. income or education). The qualitative analyses made a unique contribution to this project by generating detailed descriptions of socioeconomic differences in psychosocial factors. Those with lower levels of income and education were found to make food purchasing choices less consistent with dietary guidelines compared to those of high SEP. The psychosocial factors identified as relevant to food-purchasing inequalities were: taste preferences, health concerns, health beliefs, nutrition knowledge, nutrition concerns, weight concerns, nutrition label use, and several other values and beliefs unique to particular socioeconomic groups. Factors more tenuously or inconsistently related to socioeconomic differences in food purchasing were cost concerns, and perceived adequacy of the family diet. Evidence was displayed in both the quantitative and qualitative analyses to suggest that psychosocial factors contribute to inequalities in food purchasing in a collective manner. The quantitative analyses revealed that considerable overlap in the socioeconomic variation in food purchasing was accounted for by key psychosocial factors of importance, including taste preference, nutrition concerns, nutrition knowledge, and health concerns. Consistent with these findings, the qualitative transcripts demonstrated the interplay between such influential psychosocial factors in determining food-purchasing choices. The qualitative analyses found socioeconomic differences in the prioritisation of psychosocial factors in relation to food choices. This is suggestive of complex cultural factors that distinguish advantaged and disadvantaged groups and result in socioeconomically distinct schemas related to health and food choices. Compared to those of high SEP, those of lower SEP were less likely to indicate that health concerns, nutrition concerns, or food labels influenced food choices, and exhibited lower levels of nutrition knowledge. In the absence of health or nutrition-related concerns, taste preferences tended to dominate the food purchasing choices of those of low SEP. Overall, while cost concerns did not appear to be a main determinant of socioeconomic differences in food purchasing, this factor had a dominant influence on the food choices of some of the most disadvantaged respondents included in this research. The findings of this study have several implications for health promotion. The integrated operation of psychosocial factors on food purchasing inequalities indicates that multiple psychosocial factors may be appropriate to target in health promotion. It also seems possible that the inter-relatedness of psychosocial factors would allow health promotion targeting a single psychosocial factor to have a flow-on affect in terms of altering other influential psychosocial factors. This research also suggests that current mass marketing approaches to health promotion may not be effective across all socioeconomic groups due to differences in the priorities and main factors of influence in food purchasing decisions across groups. In addition to the practical recommendations for health promotion, this investigation, through the critique of previous research, and through the substantive study findings, has highlighted important methodological considerations for future research. Of particular note are the recommendations pertaining to the selection of socioeconomic indicators, measurement of relevant constructs, consideration of confounders, and development of an analytical approach. Addressing inequalities in health has been noted as a main objective by many health authorities and governments internationally. It is envisaged that the substantive and methodological findings of this thesis will make a useful contribution towards this important goal.
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Anthocyanin concentration is a primary determinant of plant colour. Fruit anthocyanin biosynthesis is controlled by a distinct clade of R2R3 MYB transcription factors. In apple, three recent papers describe the discovery of MYB genes activating skin, flesh and foliage anthocyanic colour. These findings lead the way to new approaches in the breeding and biotechnological development of fruit with new colour patterns.
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Background: As the human body ages, the arteries gradually lose their elasticity and become stiffer. Although inevitable, this process is influenced by hereditary and environmental factors. Interestingly, many classic cardiovascular risk factors affect the arterial stiffness. During the last decade, accelerated arterial stiffening has been recognized as an important cardiovascular risk factor associated with increased mortality as well as with several chronic disorders. Objectives: This thesis examines the role of arterial stiffness in relation to variations in a physiological feature in healthy individuals. In addition, the effect on arterial stiffness of an acute transitory disease and the effect of a chronic disease are studied. Furthermore, the thesis analyzes the prognostic value of a marker of arterial stiffness in individuals with chronic disease. Finally, a potential method of reducing arterial stiffness is evaluated. Material and study design: The first study examines pulse wave reflection and pulse wave velocity in relation to muscle fibre distribution in healthy middle-aged men. In the second study, pulse wave reflection in women with current or previous preeclampsia is compared to a healthy control group. The effect of aging on the different blood pressure indices in patients with type 1 diabetes is examined in the third study, whereas the fourth paper studies the relation between these blood pressure indices and mortality in type 2 diabetes. The fifth study evaluates how intake of a fermented milk product containing bioactive peptides affects pulse wave reflection in individuals with mild hypertension. Results and conclusions: Muscle fibre type distribution is not an independent determinant of arterial stiffness in middle-aged males. Pulse wave reflection is increased in pregnant women with preeclampsia, but not in previously preeclamptic non-pregnant women. Patients with type 1 diabetes have a higher and more rapidly increasing pulse pressure, which suggests accelerated arterial stiffening. In elderly type 2 diabetic patients, very high and very low levels of pulse pressure are associated with higher mortality. Intake of milk-derived bioactive peptides reduces pulse wave reflection in hypertensive males but not in hypertensive females.
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The zinc-finger transcription factors GATA2 and GATA3 in vertebrates belong to the six-member family that are essential regulators in the development of various organs. The aim of this study was to gain new information of the roles of GATA2 and GATA3 in inner ear morphogenesis and of the function of GATA2 in neuronal fate specification in the midbrain using genetically modified mouse and chicken embryos as models. A century ago the stepwise process of inner ear epithelial morphogenesis was described, but the molecular players regulating the cellular differentiation of the otic epithelium are still not fully resolved. This study provided novel data on GATA factor roles in several developmental processes during otic development. The expression analysis in chicken suggested that GATA2 and GATA3 possess redundant roles during otic cup and vesicle formation, but complementary cell-type specific functions during vestibular and cochlear morphogenesis. The comparative analysis between mouse and chicken Gata2 and Gata3 expression revealed many conserved aspects, especially during later stages of inner ear development, while the expression was more divergent at early stages. Namely, expression of both Gata genes was initiated earlier in chicken than mouse otic epithelium relative to the morphogenetic stages. Likewise, important differences concerning Gata3 expression in the otic cup epithelium were detected between mouse and chicken, suggesting that distinct molecular mechanisms regulate otic vesicle closure in different vertebrate species. Temporally distinct Gata2 and Gata3 expression was also found during otic ganglion formation in mouse and chicken. Targeted inactivation of Gata3 in mouse embryos caused aberrant morphology of the otic vesicle that in severe cases was disrupted into two parts, a dorsal and a ventral vesicle. Detailed analyses of Gata3 mutant embryos unveiled a crucial role for GATA3 in the initial inner ear morphogenetic event, the invagination of the otic placode. A large-scale comparative expression analysis suggested that GATA3 could control cell adhesion and motility in otic epithelium, which could be important for early morphogenesis. GATA3 was also identified as the first factor to directly regulate Fgf10 expression in the otic epithelium and could thus influence the development of the semicircular ducts. Despite the serious problems in the early inner ear development, the otic sensory fate establishment and some vestibular hair cell differentiation was observable in pharmacologically rescued Gata3-/- embryos. Cochlear sensory differentiation was, however, completely blocked so that no auditory hair cells were detected. In contrast to the early morphogenetic phenotype in Gata3-/- mutants, conditional inactivation of Gata2 in mouse embryos resulted in a relatively late growth defect of the three semicircular ducts. GATA2 was required for the proliferation of the vestibular nonsensory epithelium to support growing of the three ducts. Concurrently, with the role in epithelial semicircular ducts, GATA2 was also required for the mesenchymal cell clearance from the vestibular perilymphatic region between the membranous labyrinth and bony capsule. The gamma-aminobutyric acid-secreting (GABAergic) neurons in the midbrain are clinically relevant since they contribute to fear, anxiety, and addiction regulation. The molecular mechanisms regulating the GABAergic neuronal development, however, are largely unknown. Using tissue-specific mutagenesis in mice, GATA2 was characterized as a critical determinant of the GABAergic neuronal fate in the midbrain. In Gata2-deficient mouse midbrain, GABAergic neurons were not produced, instead the Gata2-mutant cells acquired a glutamatergic neuronal phenotype. Gain-of-function experiments in chicken also revealed that GATA2 was sufficient to induce GABAergic differentiation in the midbrain.
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Accessibility is a crucial factor for interaction between areas in economic, cultural, political and environmental terms. Therefore, information concerning accessibility is relevant for informed decision making, planning and research. The Loreto region in the Peruvian Amazonia provides an interesting scene for an accessibility study. Loreto is sparsely populated and because there are few roads in the region, in practice all movement and transportation happens along the river network. Due to the proximity of the Andes, river dynamics are strong and annual changes in water level combined with these dynamic processes constantly reshape accessibility patterns of the region. Selling non-timber forest products (NTFP) and agricultural products (AP) in regional centres is an important income source for local rain forest dwellers. Thus, accessibility to the centres is crucial for the livelihood of local population. -- In this thesis I studied how accessible the regional centre Iquitos is from other parts of Loreto. In addition, I studied the regional NTFP/AP trade patterns and compared them with patterns of accessibility. Based on GPS-measurements, using GIS, I created a time-distance surface covering Loreto. This surface describes the time-distance to Iquitos, along the river network. Based on interview material, I assessed annual changes to accessibility patterns in the region. The most common regional NTFP/AP were classified according to the amount of time they can be preserved, and based on the accessibility surface, I modelled a catchment area for each of these product classes. -- According to my results, navigation speeds vary considerably in different parts of the river network, depending on river types, vessels, flow direction and season. Navigating downstream is, generally, faster than upstream navigation. Thus, Iquitos is better accessible from areas situated south and south west of the city, like along the rivers Ucayali and Marañon. Differences in accessibility between different seasons are also substantial: during the dry season navigation is slower due to lower water levels and emerging sand bars. Regularly operating boats follow routes only along certain rivers and close to Iquitos transport facilities are more abundant than in more distant areas. Most of the products present in Iquitos market places are agricultural products, and the share of NTFP is significantly smaller. Most of the products were classified in product class 2, and the catchment area for these products is rather small. Many products also belonged to class 5, and the catchment area for these products reaches up to the edges of my study area, following the patterns of the river network. -- The accessibility model created in this study predicts travel times relatively well, although in some cases the modelled time-distances are substantially shorter than observed time-distances. This is partly caused by the fact that real-life navigation routes are more complicated than the modelled routes. Rain forest dwellers having easier access to Iquitos have more opportunities in terms of the products they decide to market. Thus, they can better take advantage of other factors affecting the market potential of different products. -- In all, understanding spatial variation in accessibility is important. In the Amazonian context it is difficult to combine the accessibility-related needs of the local dwellers with conservation purposes and the future challenge lies in finding solution that satisfy both of these needs.
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Mangrove forests in meso-tidal areas are completely drained during low tides, forming only temporary habitats for fish. We hypothesised that in such temporary habitats, where stranding risks are high, distance from tidal creeks that provided access to inundated areas during receding tides would be the primary determinant of fish distribution. Factors such as depth, root density and shade were hypothesised to have secondary effects. We tested these hypotheses in a tidally drained mangrove patch in the Andaman Islands, India. Using stake nets, we measured fish abundance and species richness relative to distance from creeks, root density/m(2), shade, water depth and size (total length) of fish. We also predicted that larger fish (including potential predators) would be closer to creeks, as they faced a greater chance of mortality if stranded. Thus we conducted tethering trials to examine if predation would be greater close to the creeks. Generalised linear mixed effects models showed that fish abundance was negatively influenced by increasing creek distance interacting with fish size and positively influenced by depth. Quantile regression analysis showed that species richness was limited by increasing creek distance. Proportion of predation was greatest close to the creeks (0-25 m) and declined with increasing distance. Abundance was also low very close to the creeks, suggesting that close to the creeks predation pressure may be an important determinant of fish abundance. The overall pattern however indicates that access to permanently inundated areas, may be an important determinant of fish distribution in tidally drained mangrove forests.