127 research outputs found

    Failure Thresholds for RCC Crest Caps

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    Overtopping protection using roller-compacted concrete (RCC) overlays is a common improvement made to address hydrologic deficiencies at existing small- to medium-height embankment dams. Overlays allow floods to pass over the dam while preventing erosion of the original embankment. The United States has many examples of such projects on both private and public dams, including many associated with federal agencies of the Departments of the Interior and Agriculture. For one project modified with an overlay in 1993, deterioration of the RCC and poor bonding between lifts has caused concern for stability of the 0.3-m (1-ft) thick RCC lifts that cap the dam. Analytical studies from 2013 to the present have assessed potential failure modes during overtopping flow and have produced widely varying estimates of the probability of failure. To address this uncertainty, physical scale modeling in the Bureau of Reclamation Hydraulics Laboratory was used to evaluate crest cap failure modes for the conservative condition of unbonded RCC lifts. The testing defines the threshold conditions for failure, which will enable effective evaluation of risk for similar facilities in the future

    Spatial risk modeling of cattle depredation by black vultures in the midwestern United States

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    ock operations through depredation of stock are a cause of human‐wildlife conflict. Management of such conflict requires identifying environmental and non‐environmental factors specific to a wildlife species\u27 biology and ecology that influence the potential for livestock depredation to occur. Identification of such factors can improve understanding of the conditions placing livestock at risk. Black vultures (Coragyps atratus) have expanded their historical range northward into the midwestern United States. Concomitantly, an increase in concern among agricultural producers regarding potential black vulture attacks on livestock has occurred. We estimated area with greater or lesser potential for depredation of domestic cattle by black vultures across a 6‐state region in the midwestern United States using an ensemble of small models (ESM). Specifically, we identified landscape‐scale spatial factors, at a zip code resolution, associated with reported black vulture depredation on cattle in midwestern landscapes to predict future potential livestock depredation. We hypothesized that livestock depredation would be greatest in areas with intensive beef cattle production close to preferred black vulture habitat (e.g., areas with fewer old fields and early successional vegetation paired with more direct edge between older forest and agricultural lands). We predicted that the density of cattle within the county, habitat structure, and proximity to anthropogenic landscape features would be the strongest predictors of black vulture livestock‐depredation risk. Our ESM estimated the relative risk of black vulture‐cattle depredation to be between 0.154–0.631 across our entire study area. Consistent with our hypothesis, areas of greatest predicted risk of depredation correspond with locations that are favorable to vulture life‐history requirements and increased potential to encounter livestock. Our results allow wildlife managers the ability to predict where black vulture depredation of cattle is more likely to occur in the future. It is in these areas where extension and outreach efforts aimed at mitigating this conflict should be focused. Researchers and wildlife managers interested in developing or employing tools aimed at mitigating livestock‐vulture conflicts can also leverage our results to select areas where depredation is most likely to occur

    Fluid-rock interaction at the backstop to the Mediterranean Ridge Accretionary Complex South of Crete : R/V SONNE Cruise Report SO278 : Emden (Germany), 12.10.2020 - Emden (Germany), 01.12.2020 : FRINGE

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    The research cruise to the Eastern Mediterranean (GPF-18-2-40) originally planned on RV METEOR was relocated to RV SONNE (Fig. 1.2) due to the reduced number of scientists as part of the corona pandemic. The main objective of the Bremen Ocean Cluster expedition (DFG, EXC2077) was to investigate the interactions between the seabed and ocean water in Greek waters, whereby the plate tectonic constellation of a broad collision zone represents a special tectonic drive. A secondary goal was the sampling of the Sartori mud volcano, which is being processed in Italian waters as part of a separate DFG project and for which the GPF granted an additional permit for ship time (GPF 20-1_054). The expedition began on 12 October in Emden/Germany and ended on 01 December 2020, in Emden. Investigations on mud volcanoes were carried out divided into 3 working areas (Fig. 1.1, the Sartori mud volcano in the Calabrian arc, the so-called Cobblestone Area, the Olimpi mud volcano field including the United Nation Ridge). With the MARUM AUV SEAL (Fig. 1.3) 11 dives were successfully carried out to create high-resolution detailed maps of certain seafloor structures. A total of 38 gravity cores (Fig. 1.4), 30 multicorers (Fig. 1.5) and 4 minicorers were used for sampling sediments and 6 CTD stations for sampling methane in the water column. Furthermore, 10 profiles were carried out with the heat flow lance and 5 observation profiles with the on-board OFOS. In four different provinces, 16 mud volcanoes were examined, 10 of which are characterized by pore waters that show a distinct freshening, while three mud volcanoes, Napoli, Heraklion and Gelendzhik, are characterized by very high salt concentrations. The salt accumulations in these structures are derived from the Messinian salt deposits in the subbed, from which salty brines arise through subrosion, which interact in various ways with the mud volcanoes. The study areas were selected based on preliminary surveys and morphological structures and increased backscatter patterns from multibeam mapping carried out over 3580 nautical miles in Italian and Greek waters.32

    CD103 Deficiency Prevents Graft-versus-Host Disease but Spares Graft-versus-Tumor Effects Mediated by Alloreactive CD8 T Cells

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    Graft-versus-host disease (GVHD) remains the main barrier to broader application of allogeneic hematopoietic stem cell transplantation (alloSCT) as a curative therapy for host malignancy. GVHD is mediated by allogeneic T cells directed against histocompatibility antigens expressed by host tissues. Based on previous studies, we postulated that the integrin CD103 is required for CD8-mediated GVHD, but not for graft-versus-tumor effects (GVT).We herein provide evidence in support of this hypothesis. To circumvent the potentially confounding influence of donor CD4 T cells, we developed an alloSCT model in which GVHD mortality is mediated by purified CD8 T cells. In this model, host-reactive CD8 T cells receive CD4 T cell help at the time of initial activation but not in the effector phase in which mature CD8 T effectors migrate into host tissues. We show that donor CD8 T cells from wild-type BALB/c mice primed to host alloantigens induce GVHD pathology and eliminate tumors of host origin in the absence of host CD4 T cells. Importantly, CD103 deficiency dramatically attenuated GVHD mortality, but had no detectable impact on the capacity to eliminate a tumor line of host origin. We provide evidence that CD103 is required for accumulation of donor CD8 T cells in the host intestinal epithelium but not in the tumor or host lymphoid compartments. Consistent with these data, CD103 was preferentially expressed by CD8 T cells infiltrating the host intestinal epithelium but not by those infiltrating the tumor, lamina propria, or lymphoid compartments. We further demonstrate that CD103 expression is not required for classic CD8 effector activities including cytokine production and cytotoxicity.These data indicate that CD103 deficiency inhibits GVHD pathology while sparing anti-tumor effects mediated by CD8 T cells, identifying CD103 blockade as an improved strategy for GVHD prophylaxis

    Evidence and argument in policymaking: development of workplace smoking legislation

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    <p>Abstract</p> <p>Background</p> <p>We sought to identify factors that affect the passage of public health legislation by examining the use of arguments, particularly arguments presenting research evidence, in legislative debates regarding workplace smoking restrictions.</p> <p>Methods</p> <p>We conducted a case-study based content analysis of legislative materials used in the development of six state workplace smoking laws, including written and spoken testimony and the text of proposed and passed bills and amendments. We coded testimony given before legislators for arguments used, and identified the institutional affiliations of presenters and their position on the legislation. We compared patterns in the arguments made in testimony to the relative strength of each state's final legislation.</p> <p>Results</p> <p>Greater discussion of scientific evidence within testimony given was associated with the passage of workplace smoking legislation that provided greater protection for public health, regardless of whether supporters outnumbered opponents or vice versa.</p> <p>Conclusion</p> <p>Our findings suggest that an emphasis on scientific discourse, relative to other arguments made in legislative testimony, might help produce political outcomes that favor public health.</p

    Trans-ancestry genome-wide association study identifies 12 genetic loci influencing blood pressure and implicates a role for DNA methylation

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    We carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 &times; 10-11 to 5.0 &times; 10-21). The sentinel blood pressure SNPs are enriched for association with DNA methylation at multiple nearby CpG sites, suggesting that, at some of the loci identified, DNA methylation may lie on the regulatory pathway linking sequence variation to blood pressure. The sentinel SNPs at the 12 new loci point to genes involved in vascular smooth muscle (IGFBP3, KCNK3, PDE3A and PRDM6) and renal (ARHGAP24, OSR1, SLC22A7 and TBX2) function. The new and known genetic variants predict increased left ventricular mass, circulating levels of NT-proBNP, and cardiovascular and all-cause mortality (P = 0.04 to 8.6 &times; 10-6). Our results provide new evidence for the role of DNA methylation in blood pressure regulation

    A Multiproxy Database of Western North American Holocene Paleoclimate Records

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    Holocene climate reconstructions are useful for understanding the diverse features and spatial heterogeneity of past and future climate change. Here we present a database of western North American Holocene paleoclimate records. The database gathers paleoclimate time series from 184 terrestrial and marine sites, including 381 individual proxy records. The records span at least 4000 of the last 12 000 years (median duration of 10 725 years) and have been screened for resolution, chronologic control, and climate sensitivity. Records were included that reflect temperature, hydroclimate, or circulation features. The database is shared in the machine readable Linked Paleo Data (LiPD) format and includes geochronologic data for generating site-level time-uncertain ensembles. This publicly accessible and curated collection of proxy paleoclimate records will have wide research applications, including, for example, investigations of the primary features of ocean-atmospheric circulation along the eastern margin of the North Pacific and the latitudinal response of climate to orbital changes. The database is available for download at https://doi.org/10.6084/m9.figshare.12863843.v1 (Routson and McKay, 2020)

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

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    BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)
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