892 resultados para Trends in disappearance


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ABSTRACTThe Amazon várzeas are an important component of the Amazon biome, but anthropic and climatic impacts have been leading to forest loss and interruption of essential ecosystem functions and services. The objectives of this study were to evaluate the capability of the Landsat-based Detection of Trends in Disturbance and Recovery (LandTrendr) algorithm to characterize changes in várzeaforest cover in the Lower Amazon, and to analyze the potential of spectral and temporal attributes to classify forest loss as either natural or anthropogenic. We used a time series of 37 Landsat TM and ETM+ images acquired between 1984 and 2009. We used the LandTrendr algorithm to detect forest cover change and the attributes of "start year", "magnitude", and "duration" of the changes, as well as "NDVI at the end of series". Detection was restricted to areas identified as having forest cover at the start and/or end of the time series. We used the Support Vector Machine (SVM) algorithm to classify the extracted attributes, differentiating between anthropogenic and natural forest loss. Detection reliability was consistently high for change events along the Amazon River channel, but variable for changes within the floodplain. Spectral-temporal trajectories faithfully represented the nature of changes in floodplain forest cover, corroborating field observations. We estimated anthropogenic forest losses to be larger (1.071 ha) than natural losses (884 ha), with a global classification accuracy of 94%. We conclude that the LandTrendr algorithm is a reliable tool for studies of forest dynamics throughout the floodplain.

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Background: It is expected that, by 2020, 15 million new cases of cancer will occur every year in the world, one million of them in Africa. Knowledge of cancer trends in African countries is far from adequate, and improvements in cancer prevention efforts are urgently needed. The aim of this study was to characterize breast cancer clinically and pathologically at presentation in Luanda, Angola; we additionally provide quality information that will be useful for breast cancer care planning in the country. Methods: Data on breast cancer cases were retrieved from the Angolan Institute of Cancer Control, from 2006 to 2014. For women diagnosed in 2009 (5-years of follow-up), demographic, clinical and pathological information, at presentation, was collected, namely age at diagnosis, parity, methods used for pathological diagnoses, tumor pathological characteristics, stage of disease and treatment. Descriptive statistics were performed. Results: The median age of women diagnosed with breast cancer in 2009 was 47 years old (range 25–89). The most frequent clinical presentation was breast swelling with axillary lymph nodes metastasis (44.9 %), followed by a mass larger than 5 cm (14.2 %) and lump (12.9 %). Invasive ductal carcinoma was the main histologic type (81.8 %). Only 10.1 % of cancer cases had a well differentiated histological grade. Cancers were diagnosed mostly at advanced stages (66.7 % in stage III and 11.1 % in stage IV). Discussion: In this study, breast cancer was diagnosed at a very advanced stage. Although it reports data from a single cancer center in Luanda, Angola it reinforces the need for early diagnosis and increasing awareness. According to the main challenges related to breast cancer diagnosis and treatment herein presented, we propose a realistic framework that would allow for the implementation of a breast cancer care program, built under a strong network based on cooperation, teaching, audit, good practices and the organization of health services. Conclusion: Angola needs urgently a program for early diagnosis of breast cancer.

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OBJECTIVE: To estimate the frequency of medical care preceding deaths due to coronary artery diseases (CAD) in different Brazilian regions and capitals and to describe trends in medical care from 1980 to 1999. METHODS: Information on medical care preceding deaths due to coronary artery diseases/acute myocardial infarction in adults > 20 years from 1980 to 1999 was collected in the DATASUS, the databank of the Brazilian Health Ministry. Sex, states, and capitals selected for 1999 were analyzed in the study. Medical care was stratified as follows: with, without, and ignored medical care. The descriptive analysis comprised frequencies, ratios of frequency, test for proportions, and increments or reductions in frequencies. RESULTS: Acute myocardial infarction (AMI) represented 75 to 85% of the CAD in the period; the frequency of deaths with medical care ranged from 48.9 to 63%, and that of ignored medical care ranged from 27.2 to 41.5%. The frequency of other CAD with medical care ranged from 56 to 76%. The frequency of deaths preceded by medical care decreased by 17.8%, and that with ignored medical care increased by 36.5% (RF=2). The values for the other CAD were -20.2% and +64.6% (RF=44.4). Deaths preceded by medical care were more frequent in females at all ages and in all Brazilian regions. CONCLUSION: The results show a high frequency of sudden death and suggest errors in diagnosis or codification and overestimation of the statistics about mortality. Validation of the death certificate diagnosis and frequent surveillance are required.

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Tourism education in Ireland has witnessed a transformation within the last four decades since CERT introduced the first fundamentals of training in the 1960’s. An analysis of the provision of tourism education in Ireland, focusing on the needs of the public, private and voluntary sectors was the main focus of this study and concentrates mainly on third level provision of tourism education within the island of Ireland. The study examines the role of tourism education in Ireland, establishing any current or emerging trends in third level tourism provision. It identifies and analyses the main stakeholders in the public, private and voluntary sectors and investigates if any requirements exist in the provision of third level education. The multi-faceted nature of the tourism industry has resulted in the provision of a diverse range of educational courses. As a result of this diversity, a question hangs over the status of tourism as a professional discipline within itself. Other issues identified through this study are the over provision of tourism courses and the current and future disparity within tourism education. The qualitative nature of the research involved questioning of major stakeholders and educators who influence tourism education provision and developing an overview of the current status of tourism education provision in Ireland identifying the present needs of each sector. Finally several strategies are suggested which may enhance third level tourism education in the future.

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The economic value of flounder from shore angling around Ireland was assessed. Flounder catches from shore angling tournaments around Ireland were related to domestic and overseas shore angling expenditure in order to determine an economic value for the species. Temporal trends in flounder angling catches, and specimen (trophy) flounder reports were also investigated. Flounder was found to be the most caught shore angling species in competitions around Ireland constituting roughly one third of the shore angling competition catch although this did vary by area. The total value of flounder from shore angling tourism was estimated to be of the order of €8.4 million. No significant temporal trends in flounder angling catches and specimen reports were found. Thus there is no evidence from the current study for any decline in flounder stocks. The population dynamics of 0-group flounder during the early benthic stage was investigated at estuarine sites in Galway Bay, west of Ireland. Information was analysed from the March to June sampling period over five years (2002 to 2006). Spatial and temporal variations in settlement and population length structure were analysed between beach and river habitats and sites. Settlement of flounder began from late March to early May of each year, most commonly in April. Peak settlement was usually in April or early May. Settlement was recorded earlier than elsewhere, although most commonly was similar to the southern part of the UK and northern France. Settlement was generally later in tidal rivers than on sandy beaches. Abundance of 0-group flounder in Galway Bay did not exhibit significant inter -annual variability. 0-group flounder were observed in dense aggregations of up to 105 m'2, which were patchy in distribution. Highest densities of 0-group flounder were recorded in limnetic and oligohaline areas as compared with the lower densities in polyhaline and to a lesser extent mesohaline areas. Measurements to of salinity allowed the classification of beaches, and tidal river sections near the mouth, into a salinity based scheme for length comparisons. Beaches were classified as polyhaline,the lower section of rivers as mesohaline, and the middle and upper sections as oligohaline. Over the March to June sampling period 0-group flounder utilised different sections at different length ranges and were significantly larger in more upstream sections. During initial settlement in April, 0-group flounder of 8-10 mm (standard length, SL) were present in abundance on polyhaline sandy beaches. By about 10mm (SL), flounder were present in all polyhaline, mesohaline and (oligohaline) sections. 0-group flounder became absent or in insignificant numbers in polyhaline and mesohaline sections in a matter of weeks after first appearance. From April to June, 0-group flounder of 12-30mm (SL) were found in more upstream locations in the oligohaline sections. About one month (May or June) after initial settlement, 0-group flounder became absent from the oligohaline sections. Concurrently, flounder start to reappear in mesohaline and polyhaline areas at approximately 30mm (SL) in June. The results indicate 0-group flounder in the early benthic stage are associated with low salinity areas, but as they grow, this association diminishes. Results strongly suggest that migration of 0-group flounder between habitats takes place during the early benthic phase.

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Abstract Background: A significant variation in pulmonary embolism (PE) mortality trends have been documented around the world. We investigated the trends in mortality rate from PE in Brazil over a period of 21 years and its regional and gender differences. Methods: Using a nationwide database of death certificate information we searched for all cases with PE as the underlying cause of death between 1989 and 2010. Population data were obtained from the Brazilian Institute of Geography and Statistics (IBGE). We calculated age-, gender- and region-specific mortality rates for each year, using the 2000 Brazilian population for direct standardization. Results: Over 21 years the age-standardized mortality rate (ASMR) fell 31% from 3.04/100,000 to 2.09/100,000. In every year between 1989 and 2010, the ASMR was higher in women than in men, but both showed a significant declining trend, from 3.10/100,000 to 2.36/100,000 and from 2.94/100,000 to 1.80/100,000, respectively. Although all country regions showed a decline in their ASMR, the largest fall in death rates was concentrated in the highest income regions of the South and Southeast Brazil. The North and Northeast regions, the lowest income areas, showed a less marked fall in death rates and no distinct change in the PE mortality rate in women. Conclusions: Our study showed a reduction in the PE mortality rate over two decades in Brazil. However, significant variation in this trend was observed amongst the five country regions and between genders, pointing to possible disparities in health care access and quality in these groups.

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This paper deals initially with the role of mineral fertilizers in increasing agricultural production: the relationship between the two variables is illustrated within global, regional national and local contexts. The pattern and trends in fertilizer usage in Brazil are presented next, namely: increase in consumption in the period 1950/72; regional distribution; consumption as related to crops and cultivated land. It is shown that in less than a quarter or century fertilizer use has increased in the country nearly 12 fold, whereas world consumption was raised 7 fold, thus exceeding estimates based in several criteria. Steps taken to secure the raise in fertilizer consumption above the historical trend are discussed: research experience for outlining fertilization recomendations; the transfer of the knowledge to the farmer by the extension work both official and private; the credit policy and special incentives for the purchase of fertilizer; the national policy for minumum proces of agricultural products; the implantation of a national fertilizer industry. It is considered that the Brazilian experience adapted to similar local conditions in other developing countries, presents a possibility for achieving beneficial results without inflationary reflexes in the economy.