136 research outputs found
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Uranium Resource Evaluation Emory Peak Quadrangle Texas
The uranium potential of the 1ΓΒ° by 2ΓΒ° Emory Peak Quadrangle, Texas, was evaluated using criteria established for the National Uranium Resource Evaluation program. Only that portion in the United States was evaluated. Surface and subsurface studies (to a depth of 5,000 ft; 1500 m) were employed, along with chemical, petrologic, hydrogeochemical, and airborne radiometric data. The western half of the quadrangle is in the Basin and Range Province and is characterized by Tertiary silicic volcanic and volcaniclastic rocks overlying Cretaceous carbonate rocks. Stocks and laccoliths of alkalic silicic to mafic rocks intrude both the Tertiary and Cretaceous rocks. The westernmost Great Plains Province (here composed of flat-lying Cretaceous carbonate rocks of the Stockton Plateau) forms the eastern half. Paleozoic leptogeosynclinal rocks of "Ouachita" facies in the Marathon Basin extend into the northern part of the quadrangle. Four environments favorable for uranium deposits have been identified: (1) basal conglomerates and (2) lacustrine-lignite deposits within the Pruett Formation, (3) fluorite deposits at the contacts between alkali rhyolite intrusions and Cretaceous carbonate rocks, and (4) alkaline rhyolitic to syenitic intrusions. Big Bend National Park is largely unevaluated because of access problems with the park service. A karst area near Dryden, which exhibits anomalous uranium, molybdenum, selenium, and arsenic concentrations in stream sediments and which exhibits radiometric anomalies, is also classed as unevaluated because little of it lies within the evaluated area. Another solution feature, the Stilwell Ranch prospect, is interesting academically but is unfavorable.Bureau of Economic Geolog
Declining Water Resources and Environmental Degradation: A Case of the Thulokhola Watershed in the Nuwakot District of Nepal
Climate change alters the hydrology of a watershed through changes on precipitation patterns, extreme rain events, increase on temperatures, degradation of forest and soil resources and drought conditions. Drought conditions create stress on agricultural crops, forests, drinking water supply for human and wildlife as well as water supply for industrial uses. Flooding destroys crops, infrastructures, private properties, and results in loss of life. Climate change impacts both the availability as well as the quality of water resources as extreme rain events tend to alter water infrastructures and pollute water sources.
In Nepal, climate change impacts include degradation of resource and ecosystem services, shrinking water storehouses, shorter winters with earlier snowmelt and natural hazards (Schild, 2007), as well as rise in mean maximum temperature and changes in the dates for the beginning and the end of the monsoons (Hua, 2009). All of these are major environmental concerns that affect water resources in Nepal. The changes in the reliability of stream flow, erratic monsoons, and flooding (Timsina, 2011) have been pronounced in recent years and adaptation to climate change has become a major issue in Nepal (Feed The Future, 2011). As a part of a larger study on livestock climate change adaptation in the mid-hills region of Nepal, the specific objectives of this study were to: (1) assess the status of water sources in the mid-hills region of Nepal, (2) assess farmersβ perceptions and understanding about the impacts of climate change on water resources, and (3) identify adaptation measures that the local communities have undertaken for climate change adaption for water resources
The Vac14pβFig4p complex acts independently of Vac7p and couples PI3,5P2 synthesis and turnover
Phosphoinositide-signaling lipids function in diverse cellular pathways. Dynamic changes in the levels of these signaling lipids regulate multiple processes. In particular, when Saccharomyces cerevisiae cells are exposed to hyperosmotic shock, PI3,5P2 (phosphatidylinositol [PI] 3,5-bisphosphate) levels transiently increase 20-fold. This causes the vacuole to undergo multiple acute changes. Control of PI3,5P2 levels occurs through regulation of both its synthesis and turnover. Synthesis is catalyzed by the PI3P 5-kinase Fab1p, and turnover is catalyzed by the PI3,5P2 5-phosphatase Fig4p. In this study, we show that two putative Fab1p activators, Vac7p and Vac14p, independently regulate Fab1p activity. Although Vac7p only regulates Fab1p, surprisingly, we find that Vac14 regulates both Fab1p and Fig4p. Moreover, Fig4p itself functions in both PI3,5P2 synthesis and turnover. In both the absence and presence of Vac7p, the Vac14pβFig4p complex controls the hyperosmotic shockβinduced increase in PI3,5P2 levels. These findings suggest that the dynamic changes in PI3,5P2 are controlled through a tight coupling of synthesis and turnover
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Uranium Resource Evaluation Presidio Quadrangle Texas
The uranium potential of the 1ΓΒ° by 2ΓΒ° Presidio Quadrangle, Texas, was evaluated using criteria devised for the National Uranium Resource Evaluation program. Surface and subsurface studies (to a 5,000 ft; 1500 m depth) were employed, along with chemical, petrologic, hydrogeochemical, and airborne radiometric data (5-mi; 8-km spacing). The entire quadrangle is in the Basin and Range Province and is characterized by Tertiary silicic volcanic rocks (caldera and outflow facies) and tuffaceous sediments, which overlie chiefly Cretaceous carbonate rocks. Presidio Bolson, a large basin filled mostly with detritus from the Chinati Caldera Complex, occupies the southwestern third of the quadrangle bordering the Rio Grande.
Favorable environments include the Allen Intrusions, a group of rhyolite domes that contain authigenic (Class 360) type deposits, and Cienega Mountain, a homogeneous riebeckite (peralkaline) rhyolite intrusion that could contain subeconomic or magmatic (Class 310) type deposits. Bolson fill exhibits several characteristics that suggest it could be favorable; however, insufficient information is available for complete evaluation, so it is classed as unevaluated. Well control is sparse; several subsurface environments are judged unfavorable chiefly by analogy with adjacent quadrangles and by projection of unfavorable outcropping rocks.Bureau of Economic Geolog
Sourcing high tissue quality brains from deceased wild primates with known socio-ecology
1. The selection pressures that drove dramatic encephalisation processes through the mammal lineage remain elusive, as does knowledge of brain structure reorganisation through this process. In particular, considerable structural brain changes are present across the primate lineage, culminating in the complex human brain that allows for unique behaviours such as language and sophisticated tool use. To understand this evolution, a diverse sample set of humans' closest relatives with varying socio-ecologies is needed. However, current brain banks predominantly curate brains from primates that died in zoological gardens. We try to address this gap by establishing a field pipeline mitigating the challenges associated with brain extractions of wild primates in their natural habitat.
2. The success of our approach is demonstrated by our ability to acquire a novel brain sample of deceased primates with highly variable socio-ecological exposure and a particular focus on wild chimpanzees. Methods in acquiring brain tissue from wild settings are comprehensively explained, highlighting the feasibility of conducting brain extraction procedures under strict biosafety measures by trained veterinarians in field sites.
3. Brains are assessed at a fine-structural level via high-resolution MRI and state-of-the-art histology. Analyses confirm that excellent tissue quality of primate brains sourced in the field can be achieved with a comparable tissue quality of brains acquired from zoo-living primates.
4. Our field methods are noninvasive, here defined as not harming living animals, and may be applied to other mammal systems than primates. In sum, the field protocol and methodological pipeline validated here pose a major advance for assessing the influence of socio-ecology on medium to large mammal brains, at both macro- and microstructural levels as well as aiding with the functional annotation of brain regions and neuronal pathways via specific behaviour assessments
Adapting Livestock Production Systems to Climate Change in Nepal: Challenges and Opportunities
To assess climate change impacts and identify challenges and opportunities for livestock climate change adaption, we conducted a comprehensive study in the Thulokhola watershed of Nuwakot district in Nepal from June 1, 2011 to January 31, 2013. We established nine community livestock groups (CLGs) consisting of 51 members and trained the CLG members in daily livestock record keeping and monitoring surface water quality. Monthly fecal samples from 50 cattle, 50 goats, and 50 buffaloes were collected for the determination of gastrointestinal parasites. Soil and fodder samples were also collected and analyzed. Group discussions, Participatory Rural Appraisals, and full-fledged household survey of 97 households were done. A survey of 41 water sources in the watershed was also conducted. While 85.3 % of the water sources have either dried up or decreased in flow in recent years, drought conditions had great toll on agricultural production. Prevalence rates of helminthes on goats, cattle, and buffalo was 53.8%, 31.32%, and 23.52%, respectively, and animal deaths were remarkably high. Declining pregnancy rates on livestock along with waning supply of fodder and forages and poor soil quality were additional major problems. Although local communities have undertaken several measures including adding new breed, destocking, purchasing fodder and forages, and planting grasses for livestock climate change adaptation, the problems of animal health, breeding conditions, soil fertility, forest degradation, increasing women workload, and water shortages were largely unaddressed. Opportunities for livestock climate change adaptation in Nepal include agroforestry intervention, groundwater utilization, rainwater harvesting, enhancing feed efficiency, and community capacity-building
VAC14 nucleates a protein complex essential for the acute interconversion of PI3P and PI(3,5)P2 in yeast and mouse
The signalling lipid PI(3,5)P2 is generated on endosomes and regulates retrograde traffic to the trans-Golgi network. Physiological signals regulate rapid, transient changes in PI(3,5)P2 levels. Mutations that lower PI(3,5)P2 cause neurodegeneration in human patients and mice. The function of Vac14 in the regulation of PI(3,5)P2 was uncharacterized previously. Here, we predict that yeast and mammalian Vac14 are composed entirely of HEAT repeats and demonstrate that Vac14 exerts an effect as a scaffold for the PI(3,5)P2 regulatory complex by direct contact with the known regulators of PI(3,5)P2: Fig4, Fab1, Vac7 and Atg18. We also report that the mouse mutant ingls (infantile gliosis) results from a missense mutation in Vac14 that prevents the association of Vac14 with Fab1, generating a partial complex. Analysis of ingls and two additional mutants provides insight into the organization of the PI(3,5)P2 regulatory complex and indicates that Vac14 mediates three distinct mechanisms for the rapid interconversion of PI3P and PI(3,5)P2. Moreover, these studies show that the association of Fab1 with the complex is essential for viability in the mouse
Osmotic stressβinduced increase of phosphatidylinositol 3,5-bisphosphate requires Vac14p, an activator of the lipid kinase Fab1p
Phosphatidylinositol 3,5-bisphosphate (PtdIns[3,5]P2) was first identified as a nonabundant phospholipid whose levels increase in response to osmotic stress. In yeast, Fab1p catalyzes formation of PtdIns(3,5)P2 via phosphorylation of PtdIns(3)P. We have identified Vac14p, a novel vacuolar protein that regulates PtdIns(3,5)P2 synthesis by modulating Fab1p activity in both the absence and presence of osmotic stress. We find that PtdIns(3)P levels are also elevated in response to osmotic stress, yet, only the elevation of PtdIns(3,5)P2 levels are regulated by Vac14p. Under basal conditions the levels of PtdIns(3,5)P2 are 18β28-fold lower than the levels of PtdIns(3)P, PtdIns(4)P, and PtdIns(4,5)P2. After a 10 min exposure to hyperosmotic stress the levels of PtdIns(3,5)P2 rise 20-fold, bringing it to a cellular concentration that is similar to the other phosphoinositides. This suggests that PtdIns(3,5)P2 plays a major role in osmotic stress, perhaps via regulation of vacuolar volume. In fact, during hyperosmotic stress the vacuole morphology of wild-type cells changes dramatically, to smaller, more highly fragmented vacuoles, whereas mutants unable to synthesize PtdIns(3,5)P2 continue to maintain a single large vacuole. These findings demonstrate that Vac14p regulates the levels of PtdIns(3,5)P2 and provide insight into why PtdIns(3,5)P2 levels rise in response to osmotic stress
Endosomal Phosphoinositides and Human Diseases
Phosphoinositides (PIs) are lipid second messengers implicated in signal transduction and membrane trafficking. Seven distinct PIs can be synthesized by phosphorylation of the inositol ring of phosphatidylinositol (PtdIns), and their metabolism is accurately regulated by PI kinases and phosphatases. Two of the PIs, PtdIns3P and PtdIns(3,5)P2, are present on intracellular endosomal compartments, and several studies suggest that they have a role in membrane remodeling and trafficking. We refer to them as βendosomal PIsβ. An increasing number of human genetic diseases including myopathy and neuropathies are associated to mutations in enzymes regulating the turnover of these endosomal PIs. The PtdIns3P and PtdIns(3,5)P2 3-phosphatase myotubularin gene is mutated in X-linked centronuclear myopathy, whereas its homologs MTMR2 and MTMR13 and the PtdIns(3,5)P2 5-phosphatase SAC3/FIG4 are implicated in CharcotβMarieβTooth peripheral neuropathies. Mutations in the gene encoding the PtdIns3P5-kinase PIP5K3/PIKfyve have been found in patients affected with FranΓ§oisβNeetens fleck corneal dystrophy. This review presents the roles of the endosomal PIs and their regulators and proposes defects of membrane remodeling as a common pathological mechanism for the corresponding diseases
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