402 resultados para Stratum


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2000 Mathematics Subject Classification: 12D10.

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After developing field sampling protocols and making a series of consultations with investigators involved in research in CSSS habitat, we determined that vegetationhydrology interactions within this landscape are best sampled at a combination of scales. At the finer scale, we decided to sample at 100 m intervals along transects that cross the range of habitats present, and at the coarser scale, to conduct an extensive survey of vegetation at sites of known sparrow density dispersed throughout the range of the CSSS. We initiated sampling in the first week of January 2003 and continued it through the last week of May. During this period, we established 6 transects, one in each CSSS subpopulation, completed topographic survey along the Transects A, C, D, and F, and sampled herb and shrub stratum vegetation, soil depth and periphyton along Transects A, and at 179 census points. We also conducted topographic surveys and completed vegetation and soil depth sampling along two of five transects used by ENP researchers for monitoring long-term vegetation change in Taylor Slough. We analyzed the data by summarizing the compositional and structural measures and by using cluster analysis, ordination, weighted averaging regression, and weighted averaging calibration. The mean elevation of transects decreased from north to south, and Transect F had greater variation than other transects. We identified eight vegetation assemblages that can be grouped into two broad categories, ‘wet prairie’ and ‘marsh’. In the 2003 survey, wet prairies were most dominant in the northeastern sub-populations, and had shorter inferred-hydroperiod, higher species richness and shallower soils than marshes, which were common in Subpopulations A, D, and the southernmost regions of Sub-population B. Most of the sites at which birds were observed during 2001 or 2002 had an inferred-hydroperiod of 120-150 days, while no birds were observed at sites with an inferred-hydroperiod less than 120 days or more than 300 days. Management-induced water level changes in Taylor Slought during the 1980’s and 1990’s appeared to elicit parallel changes in vegetation. The results described in detail in the following pages serve as a basis for evaluating and modifying, if necessary, the sampling design and analytical techniques to be used in the next three years of the project.

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Nanoemulsions are emulsified systems, characterized for reduced droplet size (50- 500nm), which the main characteristic are kinect stability and thermodynamic instability. These are promising systems on cosmetic area due to their droplet size that provide different advantages when compared to conventional systems, among others, larger surface area and better permeability. The Opuntia ficus-indica (L.) Mill is a plant cultivated on Caatinga Brazilian biome, which has great socioeconomic importance to region. This plant shows carbohydrates utilized for cosmetic industry as moisturizing active in their chemical composition. The aim of study was to develop, characterize, evaluate stability and moisturizing efficacy of cosmetic nanoemulsions added to Opuntia ficus-indica (L.) Mill extract. Nanoemulsions preparation was made using a low energy method. Different nanoemulsions were formulated varying the ratio of oil, water and surfactant phases beyond xanthan gum (0.5% e 1%) and Opuntia ficus-indica (L.) Mill hydroglycolic extract addition on 1% and 3%. Obtained nanoemulsions were submitted to preliminary and accelerated stability tests. The evaluated parameters monitored were: macroscopic aspect, pH value, droplet size, zeta potential and polydispersion index, during 60 days on different temperatures. Stable formulations were submitted to moisturizing efficacy assessment by capacitance and transepidermal water loss methodologies during 5 hours. Stable samples were white and showed homogeneous and fluid aspect, pH value was inside ideal range (4,5-6,0) to topical application and droplet size under 200nm characterizing these system as nanoemulsions. Developed nanoemulsions did not decrease transepidermal water loss, however increased the water content on stratum corneum, highlighting the nanoemulsions containing 0.5% of xanthan gum and 1% of hydroglycolic extract. This work presents cosmetic moisturizing nanoemulsions composed to vegetal raw material from Brazilian Caatinga with potential to be used on cosmetic area.

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This thesis investigates the voting behavior of the fractions of the new working class in Rio Grande do Norte, more specifically in the cities of Natal, Mossoró and Caicó, from the presidential election of 2014. This research examined the ideology, the evaluation of government and guidance the vote of a portion of the working classes of RN voters. In Brazil, from 2003, socio-economic change has occurred perceptibly, especially in a part of the working classes who ascended socially and switched to the "C economic class." Thus, there was this period, a significant expansion of this social stratum. The expansion of the "class C" in the past decade in Brazil raised the academic debate and in the media about the emergence of a "new middle class". Neri (2008) termed the "class C" of the "new middle class" and that will be the central part of their studies. But the debate on the "new middle class" can not be simplistic to the point of considering that social mobility, the main variable income, entered this segment of the population in the middle class, because it has different specificities of the popular classes. To understand this phenomenon, the income variable was outdated, adding the importance of ownership of the means of production, control of labor power and the symbolic values in the division of social classes resulting in three fractions of the new working class: the management positions, non-heads and small fighters. In this study, using as a complement to the sociological approach (ideologies and social classes) and the performance evaluation was identified that the new working class (heads) mainly reproduced the ideological and political positioning of the middle class, resulting in the rejection of PT governments (2003-2014) and it’s social, compensatory and redistributive policies. From what has been seen, the new working class (chiefs) approaches the ideological and political behavior of the middle class that will reflect in their electoral choices and class interests. The new working class (not heads and small fighters who voted in the situation) because of its classist and ideological interests approached the Workers' Party positively evaluating the Lula-Dilma governments (2003-2014) due to the implementation of compensatory policies, and redistributive programs government turned to the popular classes. In a counterpoint, the voters of the new working class (not heads and small fighters) who voted null, reproduced the discourse of mainstream media and the middle class about the rejection of compensatory policies, redistribution and government programs of Lula-Dilma governments, and consequently they disapproved of the government Dilma and her candidacy.

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Zooplankton was studied on eight stations in the marginal ice zone (MIZ) of the Barents Sea, in May 1999, along two transects across the ice edge. On each station, physical background measurements and zooplankton samples were taken every 6 h over a 24 h period at five discrete depth intervals. Cluster analysis revealed separation of open water stations from all ice stations as well as high similarity level among replicates belonging to particular station. Based on five replicates per station, analysis of variance (ANOVA) confirmed significant differences (P < 0.05) in abundances of the main mesozooplankton taxa among stations. Relations between the zooplankton community and environmental parameters were established using redundancy analysis (CANOCO). In total, 55% of mesozooplankton variability within studied area was explained by eight variables with significant conditional effects: depth stratum, fluorescence, temperature, salinity, bottom depth, latitude, bloom situation, and ice concentration. GLM models supported supposition about clear and negative relationship between concentration of Oithona similis, and overall mesozooplankton diversity The analyses showed a dynamic relationship between mesozooplankton distribution and hydrological conditions on short-term scale. Furthermore, our study demonstrated that variability in the physical environment of dynamic MIZ of the Barents Sea has measurable effect on the Arctic pelagic ecosystem.

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Human use of the oceans is increasingly in conflict with conservation of endangered species. Methods for managing the spatial and temporal placement of industries such as military, fishing, transportation and offshore energy, have historically been post hoc; i.e. the time and place of human activity is often already determined before assessment of environmental impacts. In this dissertation, I build robust species distribution models in two case study areas, US Atlantic (Best et al. 2012) and British Columbia (Best et al. 2015), predicting presence and abundance respectively, from scientific surveys. These models are then applied to novel decision frameworks for preemptively suggesting optimal placement of human activities in space and time to minimize ecological impacts: siting for offshore wind energy development, and routing ships to minimize risk of striking whales. Both decision frameworks relate the tradeoff between conservation risk and industry profit with synchronized variable and map views as online spatial decision support systems.

For siting offshore wind energy development (OWED) in the U.S. Atlantic (chapter 4), bird density maps are combined across species with weights of OWED sensitivity to collision and displacement and 10 km2 sites are compared against OWED profitability based on average annual wind speed at 90m hub heights and distance to transmission grid. A spatial decision support system enables toggling between the map and tradeoff plot views by site. A selected site can be inspected for sensitivity to a cetaceans throughout the year, so as to capture months of the year which minimize episodic impacts of pre-operational activities such as seismic airgun surveying and pile driving.

Routing ships to avoid whale strikes (chapter 5) can be similarly viewed as a tradeoff, but is a different problem spatially. A cumulative cost surface is generated from density surface maps and conservation status of cetaceans, before applying as a resistance surface to calculate least-cost routes between start and end locations, i.e. ports and entrance locations to study areas. Varying a multiplier to the cost surface enables calculation of multiple routes with different costs to conservation of cetaceans versus cost to transportation industry, measured as distance. Similar to the siting chapter, a spatial decisions support system enables toggling between the map and tradeoff plot view of proposed routes. The user can also input arbitrary start and end locations to calculate the tradeoff on the fly.

Essential to the input of these decision frameworks are distributions of the species. The two preceding chapters comprise species distribution models from two case study areas, U.S. Atlantic (chapter 2) and British Columbia (chapter 3), predicting presence and density, respectively. Although density is preferred to estimate potential biological removal, per Marine Mammal Protection Act requirements in the U.S., all the necessary parameters, especially distance and angle of observation, are less readily available across publicly mined datasets.

In the case of predicting cetacean presence in the U.S. Atlantic (chapter 2), I extracted datasets from the online OBIS-SEAMAP geo-database, and integrated scientific surveys conducted by ship (n=36) and aircraft (n=16), weighting a Generalized Additive Model by minutes surveyed within space-time grid cells to harmonize effort between the two survey platforms. For each of 16 cetacean species guilds, I predicted the probability of occurrence from static environmental variables (water depth, distance to shore, distance to continental shelf break) and time-varying conditions (monthly sea-surface temperature). To generate maps of presence vs. absence, Receiver Operator Characteristic (ROC) curves were used to define the optimal threshold that minimizes false positive and false negative error rates. I integrated model outputs, including tables (species in guilds, input surveys) and plots (fit of environmental variables, ROC curve), into an online spatial decision support system, allowing for easy navigation of models by taxon, region, season, and data provider.

For predicting cetacean density within the inner waters of British Columbia (chapter 3), I calculated density from systematic, line-transect marine mammal surveys over multiple years and seasons (summer 2004, 2005, 2008, and spring/autumn 2007) conducted by Raincoast Conservation Foundation. Abundance estimates were calculated using two different methods: Conventional Distance Sampling (CDS) and Density Surface Modelling (DSM). CDS generates a single density estimate for each stratum, whereas DSM explicitly models spatial variation and offers potential for greater precision by incorporating environmental predictors. Although DSM yields a more relevant product for the purposes of marine spatial planning, CDS has proven to be useful in cases where there are fewer observations available for seasonal and inter-annual comparison, particularly for the scarcely observed elephant seal. Abundance estimates are provided on a stratum-specific basis. Steller sea lions and harbour seals are further differentiated by ‘hauled out’ and ‘in water’. This analysis updates previous estimates (Williams & Thomas 2007) by including additional years of effort, providing greater spatial precision with the DSM method over CDS, novel reporting for spring and autumn seasons (rather than summer alone), and providing new abundance estimates for Steller sea lion and northern elephant seal. In addition to providing a baseline of marine mammal abundance and distribution, against which future changes can be compared, this information offers the opportunity to assess the risks posed to marine mammals by existing and emerging threats, such as fisheries bycatch, ship strikes, and increased oil spill and ocean noise issues associated with increases of container ship and oil tanker traffic in British Columbia’s continental shelf waters.

Starting with marine animal observations at specific coordinates and times, I combine these data with environmental data, often satellite derived, to produce seascape predictions generalizable in space and time. These habitat-based models enable prediction of encounter rates and, in the case of density surface models, abundance that can then be applied to management scenarios. Specific human activities, OWED and shipping, are then compared within a tradeoff decision support framework, enabling interchangeable map and tradeoff plot views. These products make complex processes transparent for gaming conservation, industry and stakeholders towards optimal marine spatial management, fundamental to the tenets of marine spatial planning, ecosystem-based management and dynamic ocean management.

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Delivery of large molecular weight biological molecules to the epidermis and dermis is constrained by the tough outer layer of the epidermis, the stratum corneum (sc). Microneedle technologies attempt to overcome this physical barrier using sharp micron-size projections to penetrate the sc. Dissolvable microneedles (DMN), are a particular microneedle design whereby the needle structure is composed of a soluble matrix that upon application to the skin, dissolves releasing the vaccine load into skin. This thesis examines (1) the formulation and processing considerations around DMN fabrication, (2) the immunogenicity of DMN containing trivalent influenza vaccine (TIV) in pre-clinical mouse and pig models and (3) the thermostability of these DMN formulations during storage. The results demonstrate the importance of formulation for microneedle formation and mechanical strength. Trehalose and polyvinylalcohol based formulations produced optimal microneedle structures and were amenable to piezoelectric dispensing; allowing for precise multi-layered DMN to be fabricated. The effect of drying conditions was assessed and found to be critical for DMN mechanical strength and skin penetration. The antibody responses to TIV generated by DMN-mediated vaccination were comparable or greater to those induced by immunization with a commercial TIV via the IM route in mice. DMN mediated immunisation resulted in a significantly broader humoral response to heterotypic influenza viruses compared to IM delivery. Stored at 40°C, a licensed seasonal influenza vaccine incorporated into DMN array was thermostable for at least 6 month as determined by Single Radial Immunodiffusion and immunogenicity in mice. The thesis advances the field of DMN influenza vaccination by elucidating important processing and formulation considerations in the fabrication of highly reproducible DMN. It also demonstrated that DMN can induce broader, larger humoral responses than conventional IM administration while demonstrating enhanced accelerated stability. Crucially, this works advances an automated fabrication system that will allow for clinical translation of DMN.

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Contact dermatitis is a common inflammatory skin condition characterized by erythematous and pruritic skin lesions that occur after contact with a foreign substance. There are two forms of contact dermatitis: irritant and allergic. Irritant contact dermatitis is caused by the non–immune-modulated irritation of the skin by a substance, leading to skin changes. Allergic contact dermatitis is a delayed hypersensitivity reaction in which a foreign substance comes into contact with the skin; skin changes occur after reexposure to the substance. A medical condition referred to as “shoe dermatitis” is a form of contact dermatitis caused by the contact of the foot with parts of the shoe due to these materials. Shoe dermatitis is a diagnostic and therapeutic challenge and is a common type of contact dermatitis. It is imperative the foot and ankle physician become familiar with recognizing signs and symptoms of shoe dermatitis so that their patients can be accurately diagnosis and appropriately treated to avoid secondary infections and disability. This review will first present causative factors for the etiology of shoe contact dermatitis supported by clinical-based evidence as found in the medical literature. Secondly, a description of the signs and symptoms of shoe contact dermatitis will be presented in a narrative fashion. Finally, both treatment options and preventative measures to avoid shoe.

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From the end of the 80s, the Brazilian higher education experience strong growth, coming from the private sector, which would intensify further in the late 90th Higher education has become a lucrative business. With a drop in the number of students entering and strong competition, the number of idle places in private institutions of higher education reached 49.5% in 2004. That same year, by Measure, was the University for All Program (PROUNI) program, to include high school students from public higher education, offering scholarships to those students in private HEIs. In exchange, the IES gain tax exemption. The objective of this research is to investigate the game of interest occurred in the formulation of this program and identify the model and the political game and has led to the creation of PROUNI, analyzing the process occurred since the wording of a bill, the issue of Measure Law and that the legitimacy PROUNI, with the most important changes made initial model. Since the first draft of the Law to the final Act, the PROUNI was disfigured in its main points, as the percentage of stock for paying students, the process of selection of stock and bond of the IES program. Throughout the process of creating the program, it is quite clear the performance of the institutions representing the private higher education. As reference for the analysis was based on Rational Choice Theory of Political Science. The basic argument of the methods based on rational choice is the maximization of the benefit will be the main motivation of individuals, but they can give that your goals can be achieved more effectively through institutional action and thereby discover that their conduct is shaped by institutions. Thus, individuals rationally choose to get to a certain extent constrained to join in certain institutions, whether voluntarily or not. The PROUNI was submitted by government and public policy covered by the mystical aura of the discourse of social justice and economic development, as in higher education includes a stratum of people who would not have access to the university, due to restrictions in the supply network public higher education. However, the greatest benefit from the program are the private HEIs, which through a difficult time in a scenario marked by high competition and idleness of nearly half of the vacancies offered. The PROUNI became a program that prioritizes access and not the residence of the student to higher education. More serious than a supporting program for students Fellows is a program supporting the institutions of private education

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Thesis (Ph.D.)--University of Washington, 2016-08

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The Mediterranean Sea constitutes a unique environment to study cold-seep ecosystems due to the presence of different geodynamic settings, from an active margin along the Mediterranean Ridge (MR) to a passive margin in the Nile Deep-Sea Fan (NDSF). We attempted to identify the structure of benthic communities associated with the Napoli and Amsterdam mud volcanoes (MVs) located on the MR and to establish the links between faunal distribution and environmental conditions at different spatial scales. Comparison between the 2 MVs revealed that the faunal distribution seemed to be mainly controlled by the characteristics of the microhabitats. On both geological structures, the variability between the different microhabitats was higher than the variability observed between replicates of the same microhabitat, and the distribution of macro-fauna was apparently linked to gradients in physico-chemical conditions. The peripheral sites from Napoli were generally more oxygenated and harboured lower species richness than the active sites. The reduced sediment microhabitat from Amsterdam presented the highest methane concentrations and was mainly colonised by symbiont-bearing vesicomyid bivalves and heterotrophic dorvilleid polychaetes. Overall, a higher taxonomic diversity was observed on Napoli. Sub-stratum type was hypothesised to be the second factor influencing faunal distribution. The results of this study highlight the high heterogeneity of faunal communities associated with seep ecosystems within this region and the need to pursue investigations at various spatial and temporal scales.

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Despite the increasingly high rate of implantation of cardioverter-defibrillators (ICD) in elderly patients, data supporting their clinical and cost-effectiveness in this age stratum are ambiguous and contradictory. We comprehensively reviewed the state-of-the-art data regarding the applicability, safety, clinical- and cost-effectiveness of the ICD in elderly patients, and analysed which patients in this age stratum are more likely to get a survival benefit from this therapy. Although peri-procedural risk may be slightly higher in the elderly, this procedure is still relatively safe in this age group. In terms of correcting potentially life-threatening arrhythmias, the effectiveness of ICD therapy is comparable in older and younger individuals. However, the assumption of persistent ICD benefit in the elderly population is questionable, as any advantage of the device on arrhythmic death may be largely attenuated by a higher total non-arrhythmic mortality. While septuagenarians and octogenarians have higher annual all-cause mortality rates, ICD therapy may remain effective in highly selected patients at high risk of arrhythmic death and with minimum comorbidities despite advanced age. ICD intervention among the elderly, as a group, may not be cost-effective, but the procedure may reach cost-effectiveness in those expected to live >5-7 years after implantation. Biological age rather than chronological age per se should be the decisive factor in making a decision on ICD selection for survival benefit.

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The comparative study of the vegetation of the hills of Cauda, in their unprotected and protected parts shows that on the unprotected part the vegetation is of the maquis type with the absence of the arborescent stratum and the shrub stratum is often spiny. On the contrary the protected part presents a development of the arborescent stratum; but the floristic composition of the two parts is not very different many species are identical. The evolution towards the climax seems slow on these rhyolite hills with the semi-protection.

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From the end of the 80s, the Brazilian higher education experience strong growth, coming from the private sector, which would intensify further in the late 90th Higher education has become a lucrative business. With a drop in the number of students entering and strong competition, the number of idle places in private institutions of higher education reached 49.5% in 2004. That same year, by Measure, was the University for All Program (PROUNI) program, to include high school students from public higher education, offering scholarships to those students in private HEIs. In exchange, the IES gain tax exemption. The objective of this research is to investigate the game of interest occurred in the formulation of this program and identify the model and the political game and has led to the creation of PROUNI, analyzing the process occurred since the wording of a bill, the issue of Measure Law and that the legitimacy PROUNI, with the most important changes made initial model. Since the first draft of the Law to the final Act, the PROUNI was disfigured in its main points, as the percentage of stock for paying students, the process of selection of stock and bond of the IES program. Throughout the process of creating the program, it is quite clear the performance of the institutions representing the private higher education. As reference for the analysis was based on Rational Choice Theory of Political Science. The basic argument of the methods based on rational choice is the maximization of the benefit will be the main motivation of individuals, but they can give that your goals can be achieved more effectively through institutional action and thereby discover that their conduct is shaped by institutions. Thus, individuals rationally choose to get to a certain extent constrained to join in certain institutions, whether voluntarily or not. The PROUNI was submitted by government and public policy covered by the mystical aura of the discourse of social justice and economic development, as in higher education includes a stratum of people who would not have access to the university, due to restrictions in the supply network public higher education. However, the greatest benefit from the program are the private HEIs, which through a difficult time in a scenario marked by high competition and idleness of nearly half of the vacancies offered. The PROUNI became a program that prioritizes access and not the residence of the student to higher education. More serious than a supporting program for students Fellows is a program supporting the institutions of private education

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Programa de Pós-Graduação em Ciências da Saúde, 2012.