864 resultados para DUCT EXPLORATION


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C.

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Mineralocorticoids (DOCA) are known to increase Na('+) absorption and K('+) secretion in the rabbit cortical collecting duct (CCD). However, the mechanism of regulation of the apical and basolateral cell membranes and tight junction ion conductive pathways (G('a), G('b), and G('tj), respectively) by mineralocorticoids are only partially understood. Using electrophysiological techniques and microelectrodes it was demonstrated that the apical cell membrane contained a dominant Ba('2+) sensitive K('+) conductive pathway, G(,K)('a), and an amiloride sensitive Na('+) conductive pathway, G(,Na)('a). The basolateral membrane contained a dominant Cl('-) conductive pathway, G(,Cl)('b), and a significant Ba('2+) sensitive K('+) conductive pathway, G(,K)('b). Upon elevating the mineralocorticoid levels of rabbits with intact adrenal glands it was found that V('te) was significantly increased after 1 day with a further increase after 13-16 days. These results indicated both primary and secondary effects of mineralocorticoid elevation. After 1 day of DOCA treatment, G(,Na)('a), I(,Na)('a) and I(,K)('a) increased by more than 2-fold and were maintained at high levels after 13-16 days of DOCA treatment. Secondary (chronic) effects of mineralocorticoids were evident after 4 days or more of DOCA treatment. These included a significant increase in G(,K)('a) from 4.0 to 10.2 mS.cm('-2) and a hyperpolarization of V('b) by -20 mV after 4 days of treatment. After 13-16 days of DOCA treatment V('b) remained hyperpolarized at -98.1 mV and G('tj) decreased from 5.6 to 4.2 mS.cm('-2). The hyperpolarization of V('b) was due to an increase in electrogenic Na('+) pump activity as the pump current, I(,act)('b), increased significantly from 35.7 to 195.2 (mu)A.cm('-2). Whereas net passive K('+) current across the basolateral membrane, I(,K)('b), was near zero in the control group of animals, i.e., K('+) near equilibrium, I(,K)('b) was approximately -40 (mu)A.cm('-2) in chronic DOCA treated animals. These results demonstrate that the initial effect of mineralocorticoid elevation is to increase G(,Na)('a). The ensuing depolarization of the apical membrane increases the driving force for K('+) exit into the lumen. Between 1 and 4 days of elevation, G(,K)('a) more than doubles in magnitude and at the same time the electrogenic activity of the Na('+) pump increases. This results in a hyperpolarization of V('b) which increases the driving force for K('+) uptake from the bath to the cell through a basolateral membrane conductive pathway. After 13-16 days G('tj) decreases thereby serving to maintain high electrochemical gradients across the epithelium. Therefore, the long term effects of mineralocorticoid elevation on the CCD appear to be adaptive mechanisms that serve to maintain high levels of K('+) secretion and Na('+) absorption. ^

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Pine Island, now owned by the University of Connecticut, has a rich and colorful history. Just off the Avery Point campus, the island has been home to a fertilizer factory, then a playground, and now a study site for UConn students.

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par Victor Giraud

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Objective. This study investigates the life and health goals of older adults with diabetes, and explores the factors that influence their diabetes self-management. Methods: Qualitative in-depth interviews were conducted with 24 older adults with diabetes and other morbid conditions and/or their caregivers, when appropriate. ^ Results. Participants’ provided a consistent set of responses when describing life and health goals. Participants described goals for longevity, better physical functioning, spending time with family, or maintaining independence. Diabetes discordant conditions, but not diabetes, were seen as barriers to life goals for participants with functional impairments. Functionally independent participants described additional health goals that related to diabetes self-management as diabetes was seen often a barrier to life goals. Caregivers, co-morbid conditions, denial and retirement were among the factors that influenced initiation of diabetes self-management. ^ Conclusion. Participants endorsed health goals and diabetes self-management practices that they believed would help them accomplish their life goals. Functional capabilities and social support were key factors in the relationship between diabetes self-management and their broader goals. ^ Practice implications. When planning diabetes treatments, clinicians, patients and caregivers should discuss the relationship between diabetes self-management and health and life goals as well as the affects of functional limitations and caregiver support.^

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Since early 2000, the Western Cape of South Africa has been documented as an area for monitoring the spread of HIV. The majority of HIV cases occur within individuals between the ages of 15-49 years, and the epidemic is believed to be complicated by the increased use of crystal methamphetamine (CM), or “tik.” Eighty percent of current CM users in Cape Town are under the age of 21 years, and almost 18% of current HIV cases are in individuals under the age of 24 years. Gang membership in youth may also be complicating the HIV problem as gangs feed the social acceptability of “tik” and encourage sexual violence. With almost half the population of Cape Town in their mid-twenties, the threat of a new HIV epidemic complicated by CM use has become a concern in the young adults of the city. Research into the relationships between gang membership and drugs/violence has been extensively studied in the Cape Flats. Yet, few have examined the role of gangs in the perpetuation of HIV. Therefore, the purpose of this investigation was exploratory in nature. Key informant interviews from Cape Town youth were used as case illustrations to generate potential hypotheses on the interrelationships between “gangsterism,” “tik” use, and HIV. Such awareness is important if effective efforts to reduce HIV incidence in Cape Town (and Sub-Saharan Africa) are to transpire. If the problem of CM is not addressed quickly, the Cape Flats may find itself with a higher rate of an already uncontrollable HIV epidemic. ^

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Pancreatic cancer is the 4th most common cause for cancer death in the United States, accompanied by less than 5% five-year survival rate based on current treatments, particularly because it is usually detected at a late stage. Identifying a high-risk population to launch an effective preventive strategy and intervention to control this highly lethal disease is desperately needed. The genetic etiology of pancreatic cancer has not been well profiled. We hypothesized that unidentified genetic variants by previous genome-wide association study (GWAS) for pancreatic cancer, due to stringent statistical threshold or missing interaction analysis, may be unveiled using alternative approaches. To achieve this aim, we explored genetic susceptibility to pancreatic cancer in terms of marginal associations of pathway and genes, as well as their interactions with risk factors. We conducted pathway- and gene-based analysis using GWAS data from 3141 pancreatic cancer patients and 3367 controls with European ancestry. Using the gene set ridge regression in association studies (GRASS) method, we analyzed 197 pathways from the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Using the logistic kernel machine (LKM) test, we analyzed 17906 genes defined by University of California Santa Cruz (UCSC) database. Using the likelihood ratio test (LRT) in a logistic regression model, we analyzed 177 pathways and 17906 genes for interactions with risk factors in 2028 pancreatic cancer patients and 2109 controls with European ancestry. After adjusting for multiple comparisons, six pathways were marginally associated with risk of pancreatic cancer ( P < 0.00025): Fc epsilon RI signaling, maturity onset diabetes of the young, neuroactive ligand-receptor interaction, long-term depression (Ps < 0.0002), and the olfactory transduction and vascular smooth muscle contraction pathways (P = 0.0002; Nine genes were marginally associated with pancreatic cancer risk (P < 2.62 × 10−5), including five reported genes (ABO, HNF1A, CLPTM1L, SHH and MYC), as well as four novel genes (OR13C4, OR 13C3, KCNA6 and HNF4 G); three pathways significantly interacted with risk factors on modifying the risk of pancreatic cancer (P < 2.82 × 10−4): chemokine signaling pathway with obesity ( P < 1.43 × 10−4), calcium signaling pathway (P < 2.27 × 10−4) and MAPK signaling pathway with diabetes (P < 2.77 × 10−4). However, none of the 17906 genes tested for interactions survived the multiple comparisons corrections. In summary, our current GWAS study unveiled unidentified genetic susceptibility to pancreatic cancer using alternative methods. These novel findings provide new perspectives on genetic susceptibility to and molecular mechanisms of pancreatic cancer, once confirmed, will shed promising light on the prevention and treatment of this disease. ^

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These three manuscripts are presented as a PhD dissertation for the study of using GeoVis application to evaluate telehealth programs. The primary reason of this research was to understand how the GeoVis applications can be designed and developed using combined approaches of HC approach and cognitive fit theory and in terms utilized to evaluate telehealth program in Brazil. First manuscript The first manuscript in this dissertation presented a background about the use of GeoVisualization to facilitate visual exploration of public health data. The manuscript covered the existing challenges that were associated with an adoption of existing GeoVis applications. The manuscript combines the principles of Human Centered approach and Cognitive Fit Theory and a framework using a combination of these approaches is developed that lays the foundation of this research. The framework is then utilized to propose the design, development and evaluation of “the SanaViz” to evaluate telehealth data in Brazil, as a proof of concept. Second manuscript The second manuscript is a methods paper that describes the approaches that can be employed to design and develop “the SanaViz” based on the proposed framework. By defining the various elements of the HC approach and CFT, a mixed methods approach is utilized for the card sorting and sketching techniques. A representative sample of 20 study participants currently involved in the telehealth program at the NUTES telehealth center at UFPE, Recife, Brazil was enrolled. The findings of this manuscript helped us understand the needs of the diverse group of telehealth users, the tasks that they perform and helped us determine the essential features that might be necessary to be included in the proposed GeoVis application “the SanaViz”. Third manuscript The third manuscript involved mix- methods approach to compare the effectiveness and usefulness of the HC GeoVis application “the SanaViz” against a conventional GeoVis application “Instant Atlas”. The same group of 20 study participants who had earlier participated during Aim 2 was enrolled and a combination of quantitative and qualitative assessments was done. Effectiveness was gauged by the time that the participants took to complete the tasks using both the GeoVis applications, the ease with which they completed the tasks and the number of attempts that were taken to complete each task. Usefulness was assessed by System Usability Scale (SUS), a validated questionnaire tested in prior studies. In-depth interviews were conducted to gather opinions about both the GeoVis applications. This manuscript helped us in the demonstration of the usefulness and effectiveness of HC GeoVis applications to facilitate visual exploration of telehealth data, as a proof of concept. Together, these three manuscripts represent challenges of combining principles of Human Centered approach, Cognitive Fit Theory to design and develop GeoVis applications as a method to evaluate Telehealth data. To our knowledge, this is the first study to explore the usefulness and effectiveness of GeoVis to facilitate visual exploration of telehealth data. The results of the research enabled us to develop a framework for the design and development of GeoVis applications related to the areas of public health and especially telehealth. The results of our study showed that the varied users were involved with the telehealth program and the tasks that they performed. Further it enabled us to identify the components that might be essential to be included in these GeoVis applications. The results of our research answered the following questions; (a) Telehealth users vary in their level of understanding about GeoVis (b) Interaction features such as zooming, sorting, and linking and multiple views and representation features such as bar chart and choropleth maps were considered the most essential features of the GeoVis applications. (c) Comparing and sorting were two important tasks that the telehealth users would perform for exploratory data analysis. (d) A HC GeoVis prototype application is more effective and useful for exploration of telehealth data than a conventional GeoVis application. Future studies should be done to incorporate the proposed HC GeoVis framework to enable comprehensive assessment of the users and the tasks they perform to identify the features that might be necessary to be a part of the GeoVis applications. The results of this study demonstrate a novel approach to comprehensively and systematically enhance the evaluation of telehealth programs using the proposed GeoVis Framework.

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The Central gold belt of peninsular Malaysia comprises a number of gold deposits located in the east of the N-S striking Bentong-Raub Suture Zone. The Tersang gold deposit is one of the gold deposits in the gold belt and hosted in sandstone, rhyolite and breccia units. The deposit has an inferred resource of 528,000 ounces of gold. The geochronology of the Tersang deposit has been newly constrained by LA ICP-MS U-Pb zircon dating. The maximum depositional age of the host sedimentary rocks ranges from Early Carboniferous to Early Permian (261.5 ± 4.9 Ma to 333.5 ± 2.5 Ma) for the host sandstone and Late Triassic for the rhyolite intrusion (218.8 ± 1.7 Ma). Textural characteristics of pyrite have revealed five types including (1) Euhedral to subhedral pyrite with internal fracturing and porous cores located in the sandstone layers (pyrite 1); (2) Anhedral pyrite overgrowths on pyrite 1 and disseminated in stage 1 vein (pyrite 2); (3) Fracture-filled or vein pyrite located in stages 1 and 2 vein (pyrite 3); (4) Euhedral pyrite with internal fractures also located in stage 2 vein (pyrite 4); and (5) Subhedral clean pyrite located in the rhyolite intrusion (pyrite 5). Based on pyrite mapping and spot analyses, two main stages of gold enrichment are documented from the Tersang gold deposit. Gold in sandstone-hosted pyrite 1 (mean 4.3 ppm) shows best correlation with Bi and Pb (as evidenced on pyrite maps). In addition, gold in pyrite 3 (mean 8 ppm) located in stage 2 vein shows a good correlation with As, Ag, Sb, Cu, Tl, and Pb. In terms of gold exploration, we suggest that elements such as As, Ag, Sb, Cu, Tl, Bi, and Pb associated with Au may serve as vectoring tools in gold exploration. Our new geological, structural, geochemical and isotopic data together with mineral paragenesis, pyrite chemistry and ore fluid characteristics indicate that the Tersang gold deposit is comparable to a sediment-hosted gold deposit. Our new genetic model suggests deposition of the Permo-Carboniferous sediments followed by intrusion of rhyolitic magma in the Late Triassic. At a later stage, gold mineralisation overprinted the rhyolite intrusion and the sandstone.

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Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition

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Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition

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Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition

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The Palestine Exploration Fund (PEF) Survey of Western Palestine (1871-1877) is highly praised for its accuracy and completeness; the first systematic analysis of its planimetric accuracy was published by Levin (2006). To study the potential of these 1:63,360 maps for a quantitative analysis of land cover changes over a period of time, Levin has compared them to 20th century topographic maps. The map registration error of the PEF maps was 74.4 m using 123 control points of trigonometrical stations and a 1st order polynomial. The median RMSE of all control and test points (n = 1104) was 153.6 m. Following the georeferencing of each of the 26 sheets of the PEF maps of the Survey of Western Palestine, a mosaicked file has been created. Care should be taken when analysing historical maps, as it cannot be assumed that their accuracy is consistent at different parts or for different features depicted on them.

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A walking machine is a wheeled rover alternative, well suited for work in an unstructured environment and specially in abrupt terrain. They have some drawback like speed and power consumption, but they can achieve complex movements and protrude very little the environment they are working on. The locomotion system is determined by the terrain conditions and, in our case, this legged design has been chosen based in a working area like Rio Tinto in the South of Spain, which is a river area with abrupt terrain. A walking robot with so many degrees of freedom can be a challenge when dealing with the analysis and simulations of the legs. This paper shows how to deal with the kinematical analysis of the equations of a hexapod robot based on a design developed by the Center of Astrobiology INTA-CSIC following the classical formulation of equations