670 research outputs found
Atitudes com relação à polícia em uma favela no sul do Brasil
Em pesquisa realizada pelo autor e mais quatro colegas na maior favela da cidade de Porto Alegre foi detectada uma atitude bastante consistente com relação à polícia: ela é temida e odiada pela grande maioria ao contrário da gangue local que era muito integrada e respeitada pela comunidade. O objetivo do artigo é portanto tentar mostrar as razões desse paradoxo.Research carried out by the author and four colleagues in the largest slum (favela) in the city of Porto Alegre, showed a consistency in attitudes toward the police: they were feared and desliked by most people. Meanwhile, the local gangue was well integrated and trusted by the community. The objective of this article is to show the reasons for this paradox
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Geologic Analysis of Primary and Secondary Tight Gas Sand Objectives, Phase C
Previous assessments of blanket-geometry tight gas sandstones led to the selection of the Travis Peak Formation of the East Texas and North Louisiana Basins and the Corcoran and Cozzette Sandstones of the Piceance Creek Basin as major research objectives. The anticipated outcomes of this study include increased availability of tight gas resources and advancements in technology with high transferability. The work reported here encompasses all aspects of the depositional systems and reservoir geology of these units as fundamental components of resource characterization, with an emphasis on understanding controls on reservoir facies distribution and their relevance to low-permeability reservoir development.
Six lithofacies of the Travis Peak (Hosston) Formation in East Texas and North Louisiana have been identified using electric logs. These facies comprise sand-rich fluvial-deltaic, silt-rich delta-front, clay- and carbonate-rich shelf, carbonate reef, and clay-rich open marine facies. The most well-developed facies in the East Texas area are the fluvial-deltaic and delta-front facies. Travis Peak rocks from the Clayton Williams #11 Sam Hughes well, Panola County, Texas, were primarily deposited in a fluvial environment within a coastal plain setting. Porosity and permeability control in the clean sandstones are primarily attributed to quartz overgrowths, chlorite cement, and solid organic matter, with approximately half of the remaining porosity being secondary, resulting from framework grain dissolution.
Studies of Travis Peak gas production at Pinehill Southeast and Percy-Wheeler fields indicate an average permeability-thickness product of about 10 md-ft, with a range of 0.7 to 35 md-ft, indicating dry gas reservoirs. Well logs, core, and mud logs from Chapel Hill field in Smith County, Texas, were examined in preparation for a complete cooperative well program in the ARCO #11 Phillips well on the western margin of that field.
Field studies of Corcoran-Cozzette Sandstones near Grand Junction, Colorado, suggest that the depositional environments of the Corcoran evolved from marine upper shoreface to non-marine, while the Cozzette sequence evolved from lower to upper shoreface. Porosity and water saturation calculations have been conducted by computer for seven Corcoran and Cozzette depositional units. A comparison of calculated water saturation with core-derived porosity and permeability indicates a fair to very good correlation of reservoir properties with clay content measured by gamma-ray log.Bureau of Economic Geolog
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Geology of the Lower Cretaceous Travis Peak Formation, East Texas: Characterization of a Tight Gas SandStone
Since 1982, the Gas Research Institute (GRI) Tight Gas Sands Project has supported geological investigations designed to develop knowledge necessary to efficiently produce low-permeability, gas-bearing sandstones. As part of that program, the Bureau of Economic Geology has conducted research on low-permeability sandstone in the Lower Cretaceous Travis Peak (Hosston) Formation in East Texas.
The first phase of the study, which lasted from 1983 until 1986, involved extensive collection of core and production data in seven cooperative wells. Information gained from the cooperative wells, combined with geologic characterization of the Travis Peak throughout the study area, led to the drilling by GRI of three Staged Field Experiment (SFE) wells between 1986 and 1988. The SFE wells were drilled and completed by GRI specifically for the purpose of research on low-permeability gas reservoirs.
This report summarizes the results of the geologic studies of the Travis Peak Formation, and it focuses on the contribution of geology to evaluation and completion of tight gas sandstone wells.Bureau of Economic Geolog
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Geology of the Lower Cretaceous Travis Peak Formation, East Texas: Depositional History, Diagenesis Structure and Reservoir Engineering Implications
This report summarizes stratigraphic, petrographic, and structural studies of the Lower Cretaceous Travis Peak Formation, a low-permeability gas sandstone in East Texas, and presents reservoir engineering implications. Depositional systems in this region were interpreted from logs and cores and include (1) a braided- to meandering-fluvial system that forms the majority of the Travis Peak section; (2) deltaic deposits interbedded with the distal part of the fluvial system; (3) paralic deposits that overlie and interfinger with the deltaic and fluvial deposits near the top of the Travis Peak; and (4) shelf deposits present at the downdip extent of the formation. Petrographic studies indicate the sandstones are quartzarenites and subarkoses. Cementation by quartz, dolomite, ankerite, illite, chlorite, and reservoir bitumen have reduced porosity to less than 8 percent and permeability to less than 0.1 md throughout most of the formation. Structurally deeper sandstones are more intensely quartz cemented than are shallower sandstones and contain abundant, open natural fractures. Borehole breakouts and drilling-induced fractures in core can be used to predict horizontal stress directions and the direction of hydraulic fracture propagation. Hydraulic fractures propagate in directions subparallel to the east-northeast strike of the natural fractures; thus, hydraulically induced fractures may not intersect many natural fractures.Bureau of Economic Geolog
Once and Future Gulf of Mexico Ecosystem: Restoration Recommendations of an Expert Working Group
The Deepwater Horizon (DWH) well blowout released more petroleum hydrocarbons into the marine environment than any previous U.S. oil spill (4.9 million barrels), fouling marine life, damaging deep sea and shoreline habitats and causing closures of economically valuable fisheries in the Gulf of Mexico. A suite of pollutants—liquid and gaseous petroleum compounds plus chemical dispersants—poured into ecosystems that had already been stressed by overfishing, development and global climate change. Beyond the direct effects that were captured in dramatic photographs of oiled birds in the media, it is likely that there are subtle, delayed, indirect and potentially synergistic impacts of these widely dispersed, highly bioavailable and toxic hydrocarbons and chemical dispersants on marine life from pelicans to salt marsh grasses and to deep-sea animals. As tragic as the DWH blowout was, it has stimulated public interest in protecting this economically, socially and environmentally critical region. The 2010 Mabus Report, commissioned by President Barack Obama and written by the secretary of the Navy, provides a blueprint for restoring the Gulf that is bold, visionary and strategic. It is clear that we need not only to repair the damage left behind by the oil but also to go well beyond that to restore the anthropogenically stressed and declining Gulf ecosystems to prosperity-sustaining levels of historic productivity. For this report, we assembled a team of leading scientists with expertise in coastal and marine ecosystems and with experience in their restoration to identify strategies and specific actions that will revitalize and sustain the Gulf coastal economy. Because the DWH spill intervened in ecosystems that are intimately interconnected and already under stress, and will remain stressed from global climate change, we argue that restoration of the Gulf must go beyond the traditional "in-place, in-kind" restoration approach that targets specific damaged habitats or species. A sustainable restoration of the Gulf of Mexico after DWH must: 1. Recognize that ecosystem resilience has been compromised by multiple human interventions predating the DWH spill; 2. Acknowledge that significant future environmental change is inevitable and must be factored into restoration plans and actions for them to be durable; 3. Treat the Gulf as a complex and interconnected network of ecosystems from shoreline to deep sea; and 4. Recognize that human and ecosystem productivity in the Gulf are interdependent, and that human needs from and effects on the Gulf must be integral to restoration planning. With these principles in mind, the authors provide the scientific basis for a sustainable restoration program along three themes: 1. Assess and repair damage from DWH and other stresses on the Gulf; 2. Protect existing habitats and populations; and 3. Integrate sustainable human use with ecological processes in the Gulf of Mexico. Under these themes, 15 historically informed, adaptive, ecosystem-based restoration actions are presented to recover Gulf resources and rebuild the resilience of its ecosystem. The vision that guides our recommendations fundamentally imbeds the restoration actions within the context of the changing environment so as to achieve resilience of resources, human communities and the economy into the indefinite future
A Once and Future Gulf of Mexico Ecosystem: Restoration Recommendations of an Expert Working Group
The Deepwater Horizon (DWH) well blowout released more petroleum hydrocarbons into the marine environment than any previous U.S. oil spill (4.9 million barrels), fouling marine life, damaging deep sea and shoreline habitats and causing closures of economically valuable fisheries in the Gulf of Mexico. A suite of pollutants — liquid and gaseous petroleum compounds plus chemical dispersants — poured into ecosystems that had already been stressed by overfishing, development and global climate change. Beyond the direct effects that were captured in dramatic photographs of oiled birds in the media, it is likely that there are subtle, delayed, indirect and potentially synergistic impacts of these widely dispersed, highly bioavailable and toxic hydrocarbons and chemical dispersants on marine life from pelicans to salt marsh grasses and to deep-sea animals.
As tragic as the DWH blowout was, it has stimulated public interest in protecting this economically, socially and environmentally critical region. The 2010 Mabus Report, commissioned by President Barack Obama and written by the secretary of the Navy, provides a blueprint for restoring the Gulf that is bold, visionary and strategic. It is clear that we need not only to repair the damage left behind by the oil but also to go well beyond that to restore the anthropogenically stressed and declining Gulf ecosystems to prosperity-sustaining levels of historic productivity. For this report, we assembled a team of leading scientists with expertise in coastal and marine ecosystems and with experience in their restoration to identify strategies and specific actions that will revitalize and sustain the Gulf coastal economy.
Because the DWH spill intervened in ecosystems that are intimately interconnected and already under stress, and will remain stressed from global climate change, we argue that restoration of the Gulf must go beyond the traditional “in-place, in-kind” restoration approach that targets specific damaged habitats or species. A sustainable restoration of the Gulf of Mexico after DWH must:
1. Recognize that ecosystem resilience has been compromised by multiple human interventions predating the DWH spill;
2. Acknowledge that significant future environmental change is inevitable and must be factored into restoration plans and actions for them to be durable;
3. Treat the Gulf as a complex and interconnected network of ecosystems from shoreline to deep sea; and
4. Recognize that human and ecosystem productivity in the Gulf are interdependent, and that human needs from and effects on the Gulf must be integral to restoration planning.
With these principles in mind, we provide the scientific basis for a sustainable restoration program along three themes:
1. Assess and repair damage from DWH and other stresses on the Gulf;
2. Protect existing habitats and populations; and
3. Integrate sustainable human use with ecological processes in the Gulf of Mexico.
Under these themes, 15 historically informed, adaptive, ecosystem-based restoration actions are presented to recover Gulf resources and rebuild the resilience of its ecosystem. The vision that guides our recommendations fundamentally imbeds the restoration actions within the context of the changing environment so as to achieve resilience of resources, human communities and the economy into the indefinite future
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An Assessment of the Natural Gas Resource Base of the United States
The distribution of natural gas in the United States comprises proved reserves in known reservoirs, inferred reserves, undeveloped resources within these reservoirs, and undiscovered resources. Beyond proved reserves, all volumes of future natural gas supply are estimates based on information derived from past and current experience in gas production and reservoir development. Even proved reserves are subject to periodic revision. This assessment begins with an understanding of major components of the natural gas supply derived from existing resource estimates that use established methodologies. In addition to historically defined elements of the resource base, a new component—reserve growth in heterogeneous reservoirs—is quantified in this study.
Resource assessments proceed in their planning and compilation from reasonably well-known quantities (proved reserves) to increasingly less well-known quantities (undiscovered resources). Furthermore, natural gas reservoirs termed unconventional are typically given separate consideration and include gas in low-permeability reservoirs, gas in shale formations such as the Devonian of the Eastern U.S., and coalbed methane resources. This approach has been followed in this assessment. Special note was made of Alaskan gas reserves as they are significant and proven, but transportation for North Slope gas to the Lower 48 states is lacking.Bureau of Economic Geolog
3′-End Sequencing for Expression Quantification (3SEQ) from Archival Tumor Samples
Gene expression microarrays are the most widely used technique for genome-wide expression profiling. However, microarrays do not perform well on formalin fixed paraffin embedded tissue (FFPET). Consequently, microarrays cannot be effectively utilized to perform gene expression profiling on the vast majority of archival tumor samples. To address this limitation of gene expression microarrays, we designed a novel procedure (3′-end sequencing for expression quantification (3SEQ)) for gene expression profiling from FFPET using next-generation sequencing. We performed gene expression profiling by 3SEQ and microarray on both frozen tissue and FFPET from two soft tissue tumors (desmoid type fibromatosis (DTF) and solitary fibrous tumor (SFT)) (total n = 23 samples, which were each profiled by at least one of the four platform-tissue preparation combinations). Analysis of 3SEQ data revealed many genes differentially expressed between the tumor types (FDR<0.01) on both the frozen tissue (∼9.6K genes) and FFPET (∼8.1K genes). Analysis of microarray data from frozen tissue revealed fewer differentially expressed genes (∼4.64K), and analysis of microarray data on FFPET revealed very few (69) differentially expressed genes. Functional gene set analysis of 3SEQ data from both frozen tissue and FFPET identified biological pathways known to be important in DTF and SFT pathogenesis and suggested several additional candidate oncogenic pathways in these tumors. These findings demonstrate that 3SEQ is an effective technique for gene expression profiling from archival tumor samples and may facilitate significant advances in translational cancer research
Decreased venous thrombosis with an oral inhibitor of P selectin
BackgroundP-selectin inhibition with protein therapeutics such as antibodies or soluble ligands given intravenously can decrease thrombosis in a mouse ligation model of venous thrombosis. In this study, we hypothesized that oral inhibition of P selectin with a novel oral nonprotein inhibitor (PSI-697) would decrease thrombosis and circulating microparticle populations. This study evaluated the effects on thrombosis and circulating microparticle populations in this murine venous thrombosis model.MethodsMice underwent inferior vena cava ligation to induce thrombosis. Mice with high circulating level of P selectin, Delta Cytoplasmic Tail (^CT), mice gene-deleted for both E- and P-selectin knockout (EPKO), and wild-type C57BL/6 mice (WT) were studied without and with administration of PSI-697 in food (100 mg/kg daily) from 2 days before thrombosis until the end of the study. Animals were killed 2 and 6 days later. Evaluations included thrombus weight (TW), vein wall morphometrics, microparticle quantification by using fluorescence-activated cell sorter analysis, and vein wall enzyme-linked immunosorbent assays for interleukin (IL)-10, P selectin, and monocyte chemotactic protein 1.ResultsPSI-697 significantly decreased TW in WT and ^CT mice, with a treated vs nontreated TW of 132 ± 24 vs 228 ± 29 × 10−4 g (P = .014) and 166 ± 19 vs 281 ± 16 × 10−4 g (P = .001), respectively. At day 6, the effect was significant only in the ^CT group (P < .05). Drug therapy at day 2 significantly increased vein wall monocytes in WT mice and increased monocytes and total inflammatory cells in ^CT animals. A significant decrease in neutrophils and total inflammatory cells was seen in EPKO mice at day 2 with therapy. Therapy significantly increased platelet-derived microparticles and total microparticles in ^CT mice on day 2. Changes in treated WT and treated EPKO animals were not significant compared with respective vehicle treatments at day 2. On day 6, therapy significantly decreased total microparticles in EPKO animals. Vein wall expression of IL-10 increased in all groups with therapy at day 2 (n = 18) and was significantly increased in WT (2687.5 ± 903 pg/mL vs 636 ± 108 pg/mL total protein; P = .038) and ^CT (2078 ± 295 pg/mL vs 432 ± 62 pg/mL total protein; P = .001) mice. Therapy significantly decreased vein wall P selectin, monocyte chemotactic protein 1, and IL-10 levels at day 6.ConclusionsPSI-697 decreased thrombosis. P-selectin inhibition allowed vein wall inflammatory cell extravasation in this model of complete ligation. Circulating microparticles (platelet-derived microparticles and total microparticles) increased with P-selectin inhibition, possibly because of decreased consumption into the thrombus. In summary, the oral administration of an inhibitor to P selectin provides significant TW reduction.Clinical RelevanceDeep venous thrombosis is a significant national health problem in the general population. The average annual incidence of deep venous thrombosis is approximately 250,000 cases per year. The selectin family of adhesion molecules is thought to be largely responsible for the initial attachment and rolling of leukocytes on stimulated vascular endothelium. Recent studies have explored the possible therapeutic implications of P-selectin inhibition to modulate venous thrombosis. For example, prophylactic dosing of a recombinant P-selectin ligand decreases venous thrombosis in a dose-dependent fashion in both feline and nonhuman primate animal models. Additionally, treatment of 2-day iliac thrombi with a recombinant protein, P-selectin inhibitor, significantly improves vein reopening in nonhuman primates. It is interesting to note that P-selectin inhibition decreases thrombosis without adverse anticoagulation. On the basis of the results from these previous studies, the use of P-selectin antagonism is a logical therapeutic approach to treat venous thrombosis. All inhibitors developed to date are either proteins or small molecules with low oral bioavailability that require intravenous or subcutaneous injection. This study evaluates, for the first time, a novel orally bioavailable inhibitor of P-selectin (PSI-697)
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