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Grindr Users Take More Risks, but Are More Open to Human Immunodeficiency Virus (HIV) Pre-exposure Prophylaxis: Could This Dating App Provide a Platform for HIV Prevention Outreach?
BackgroundTechnology has changed the way that men who have sex with men (MSM) seek sex. More than 60% of MSM in the United States use the internet and/or smartphone-based geospatial networking apps to find sex partners. We correlated use of the most popular app (Grindr) with sexual risk and prevention behavior among MSM.MethodsA nested cohort study was conducted between September 2018 and June 2019 among MSM receiving community-based human immunodeficiency virus (HIV) and sexually transmitted infection (STI) screening in central San Diego. During the testing encounter, participants were surveyed for demographics, substance use, risk behavior (previous 3 months), HIV pre-exposure prophylaxis (PrEP) use, and Grindr usage. Participants who tested negative for HIV and who were not on PrEP were offered immediate PrEP.ResultsThe study included 1256 MSM, 1090 of whom (86.8%) were not taking PrEP. Overall, 580 of 1256 (46%) participants indicated that they used Grindr in the previous 7 days. Grindr users reported significantly higher risk behavior (greater number of male partners and condomless sex) and were more likely to test positive for chlamydia or gonorrhea (8.6% vs 4.7% of nonusers; P = .005). Grindr users were also more likely to be on PrEP (18.7% vs 8.7% of nonusers; P < .001) and had fewer newly diagnosed HIV infections (9 vs 26 among nonusers; P = .014). Grindr users were also nearly twice as likely as nonusers to initiate PrEP (24.6% vs 14%; P < .001).ConclusionsGiven the higher risk behavior and greater acceptance of PrEP among MSM who used Grindr, Grindr may provide a useful platform to promote HIV and STI testing and increase PrEP uptake
Archaeological Survey of Southwest Block and Selected Roads and Firebreaks at Camp Maxey, Lamar County, Texas
In June, July, and September 1998, The Center for Archaeological Research (CAR) of The University of Texas at San Antonio (UTSA) conducted an archaeological survey of approximately 1,000 acres for the Texas Army National Guard (TXARNG) on Camp Maxey, a TXARNG training facility in north-central Lamar County, Texas, under Sections 106 and 110 of the National Historic Preservation Act and the Antiquities Code of Texas. The TXARNG had identified the 1,000-acre area for possible impact associated with the construction of firebreaks, road improvements, and subsequent military training with tracked and wheeled vehicles. Thirty archaeological sites were found and documented. Twenty-three sites contained a prehistoric component only, five sites contained a historic component only, and two sites contained both a prehistoric and historic component.
Based on the results of the pedestrian survey and limited shovel testing, CAR recommends that the following sites are insignificant and therefore ineligible for inclusion in the National Register of Historic Places or for designation as State Archaeological Landmarks: 41LR149, 41LR150, 41LR151, 41LR169, 41LR171, 41LR172, 41LR173, 41LR174, 41LR176, 41LR178, and 41LR179. CAR recommends that because the significance of the following sites is unknown, the TXARNG either avoid further impact to them, or conduct test excavations to determine their significance: 41LR152, 41LR153, 41LR154, 41LR155, 41LR156, 41LR157, 41LR158, 41LR159, 41LR160, 41LR161, 41LR162, 41LR163, 41LR164, 41LR165, 41LR166, 41LR167, 41LR168, 41LR175, and 41LR177
Sulfur K-Edge XAS Studies of the Effect of DNA Binding on the [Fe_4S_4] Site in EndoIII and MutY
S K-edge X-ray absorption spectroscopy (XAS) was used to study the [Fe_4S_4] clusters in the DNA repair glycosylases EndoIII and MutY to evaluate the effects of DNA binding and solvation on Fe–S bond covalencies (i.e., the amount of S 3p character mixed into the Fe 3d valence orbitals). Increased covalencies in both iron–thiolate and iron–sulfide bonds would stabilize the oxidized state of the [Fe_4S_4] clusters. The results are compared to those on previously studied [Fe_4S_4] model complexes, ferredoxin (Fd), and to new data on high-potential iron–sulfur protein (HiPIP). A limited decrease in covalency is observed upon removal of solvent water from EndoIII and MutY, opposite to the significant increase observed for Fd, where the [Fe_4S_4] cluster is solvent exposed. Importantly, in EndoIII and MutY, a large increase in covalency is observed upon DNA binding, which is due to the effect of its negative charge on the iron–sulfur bonds. In EndoIII, this change in covalency can be quantified and makes a significant contribution to the observed decrease in reduction potential found experimentally in DNA repair proteins, enabling their HiPIP-like redox behavior
LabKey Server NAb: A tool for analyzing, visualizing and sharing results from neutralizing antibody assays
<p>Abstract</p> <p>Background</p> <p>Multiple types of assays allow sensitive detection of virus-specific neutralizing antibodies. For example, the extent of antibody neutralization of HIV-1, SIV and SHIV can be measured in the TZM-bl cell line through the degree of luciferase reporter gene expression after infection. In the past, neutralization curves and titers for this standard assay have been calculated using an Excel macro. Updating all instances of such a macro with new techniques can be unwieldy and introduce non-uniformity across multi-lab teams. Using Excel also poses challenges in centrally storing, sharing and associating raw data files and results.</p> <p>Results</p> <p>We present LabKey Server's NAb tool for organizing, analyzing and securely sharing data, files and results for neutralizing antibody (NAb) assays, including the luciferase-based TZM-bl NAb assay. The customizable tool supports high-throughput experiments and includes a graphical plate template designer, allowing researchers to quickly adapt calculations to new plate layouts. The tool calculates the percent neutralization for each serum dilution based on luminescence measurements, fits a range of neutralization curves to titration results and uses these curves to estimate the neutralizing antibody titers for benchmark dilutions. Results, curve visualizations and raw data files are stored in a database and shared through a secure, web-based interface. NAb results can be integrated with other data sources based on sample identifiers. It is simple to make results public after publication by updating folder security settings.</p> <p>Conclusions</p> <p>Standardized tools for analyzing, archiving and sharing assay results can improve the reproducibility, comparability and reliability of results obtained across many labs. LabKey Server and its NAb tool are freely available as open source software at <url>http://www.labkey.com</url> under the Apache 2.0 license. Many members of the HIV research community can also access the LabKey Server NAb tool without installing the software by using the Atlas Science Portal (<url>https://atlas.scharp.org</url>). Atlas is an installation of LabKey Server.</p
Regional distribution of fatiguing illnesses in the United States: a pilot study
BACKGROUND: Chronic fatigue syndrome (CFS) is a debilitating illness with no known cause or effective therapy. Population-based epidemiologic data on CFS prevalence are critical to put CFS in a realistic context for public health officials and others responsible for allocating resources. METHODS: We conducted a pilot random-digit-dialing survey to estimate the prevalence of fatiguing illnesses in different geographic regions and in urban and rural populations of the United States. This report focuses on 884 of 7,317 respondents 18 to 69 years old. Fatigued (440) and randomly selected non-fatigued (444) respondents completed telephone questionnaires concerning fatigue, other symptoms, and medical history. RESULTS: We estimated 12,186 per 100,000 persons 18 to 69 years of age suffered from fatigue lasting for at least 6 months (chronic fatigue), and 1,197 per 100,000 described an illness that, though lacking clinical evaluation, met criteria for CFS (CFS-like). Chronic fatigue and CFS-like illness were more common in rural than in urban populations, although the differences were not significant. The prevalence of these fatiguing illnesses did not differ meaningfully among the four regions surveyed, and no significant geographic trends were observed. CONCLUSIONS: This investigation estimated that nearly 2.2 million American adults suffer from CFS-like illness. The study also suggested the need to focus future investigations of fatigue on populations with lower incomes and less education. There was no evidence for regional differences in the occurrence of fatiguing illnesses
The Geometry of Cold, Metal-Enriched Gas Around Galaxies at
We present the first results from a Hubble Space Telescope WFC3/IR program,
which obtained direct imaging and grism observations of galaxies near quasar
sightlines with a high frequency of uncorrelated foreground Mg II absorption.
These highly efficient observations targeted 54 Mg II absorbers along the line
of sight to nine quasars at . We find that 89% of the absorbers
in the range can be spectroscopically matched to at least one
galaxy with an impact parameter less than 200 kpc and .
We have estimated the star formation rates and measured structural parameters
for all detected galaxies with impact parameters in the range 7-200 kpc and
star formation rates greater than 1.3 M yr. We find that
galaxies associated with Mg II absorption have significantly higher mean star
formation rates and marginally higher mean star formation rate surface
densities compared to galaxies with no detected Mg II. Nearly half of the Mg II
absorbers match to more than one galaxy, and the mean equivalent width of the
Mg II absorption is found to be greater for groups, compared to isolated
galaxies. Additionally, we observe a significant redshift evolution in the
physical extent of Mg II-absorbing gas around galaxies and evidence of an
enhancement of Mg II within 50 degrees of the minor axis, characteristic of
outflows, which persists to 80 kpc around the galaxies, in agreement with
recent predictions from simulations.Comment: 21 pages, 20 figures, Submitted to Ap
A low density of 0.8 g/cc for the Trojan binary asteroid 617 Patroclus
The Trojan population consists of two swarms of asteroids following the same
orbit as Jupiter and located at the L4 and L5 Lagrange points of the
Jupiter-Sun system (leading and following Jupiter by 60 degrees). The asteroid
617 Patroclus is the only known binary Trojan (Merline et al. 2001). The orbit
of this double system was hitherto unknown. Here we report that the components,
separated by 680 km, move around the system centre of mass, describing roughly
a circular orbit. Using the orbital parameters, combined with thermal
measurements to estimate the size of the components, we derive a very low
density of 0.8 g/cc. The components of Patroclus are therefore very porous or
composed mostly of water ice, suggesting that they could have been formed in
the outer part of the solar system.Comment: 10 pages, 3 figures, 1 tabl
Rapid, selective heavy metal removal from water by a metal-organic framework/polydopamine composite
Drinking water contamination with heavy metals, particularly lead, is a persistent problem worldwide with grave public health consequences. Existing purification methods often cannot address this problem quickly and economically. Here we report a cheap, water stable metal–organic framework/polymer composite, Fe-BTC/PDA, that exhibits rapid, selective removal of large quantities of heavy metals, such as Pb2+ and Hg2+, from real world water samples. In this work, Fe-BTC is treated with dopamine, which undergoes a spontaneous polymerization to polydopamine (PDA) within its pores via the Fe3+ open metal sites. The PDA, pinned on the internal MOF surface, gains extrinsic porosity, resulting in a composite that binds up to 1634 mg of Hg2+ and 394 mg of Pb2+ per gram of composite and removes more than 99.8% of these ions from a 1 ppm solution, yielding drinkable levels in seconds. Further, the composite properties are well-maintained in river and seawater samples spiked with only trace amounts of lead, illustrating unprecedented selectivity. Remarkably, no significant uptake of competing metal ions is observed even when interferents, such as Na+, are present at concentrations up to 14 000 times that of Pb2+. The material is further shown to be resistant to fouling when tested in high concentrations of common organic interferents, like humic acid, and is fully regenerable over many cycles
Multicenter, Observational Cohort Study Evaluating Third-Generation Cephalosporin Therapy for Bloodstream Infections Secondary to Enterobacter, Serratia, and Citrobacter Species
Objectives: There is debate on whether the use of third-generation cephalosporins (3GC) increases the risk of clinical failure in bloodstream infections (BSIs) caused by chromosomally-mediated AmpC-producing Enterobacterales (CAE). This study evaluates the impact of definitive 3GC therapy versus other antibiotics on clinical outcomes in BSIs due to Enterobacter, Serratia, or Citrobacter species. Methods: This multicenter, retrospective cohort study evaluated adult hospitalized patients with BSIs secondary to Enterobacter, Serratia, or Citrobacter species from 1 January 2006 to 1 September 2014. Definitive 3GC therapy was compared to definitive therapy with other non-3GC antibiotics. Multivariable Cox proportional hazards regression evaluated the impact of definitive 3GC on overall treatment failure (OTF) as a composite of in-hospital mortality, 30-day hospital readmission, or 90-day reinfection. Results: A total of 381 patients from 18 institutions in the southeastern United States were enrolled. Common sources of BSIs were the urinary tract and central venous catheters (78 (20.5%) patients each). Definitive 3GC therapy was utilized in 65 (17.1%) patients. OTF occurred in 22/65 patients (33.9%) in the definitive 3GC group vs. 94/316 (29.8%) in the non-3GC group (p = 0.51). Individual components of OTF were comparable between groups. Risk of OTF was comparable with definitive 3GC therapy vs. definitive non-3GC therapy (aHR 0.93, 95% CI 0.51–1.72) in multivariable Cox proportional hazards regression analysis. Conclusions: These outcomes suggest definitive 3GC therapy does not significantly alter the risk of poor clinical outcomes in the treatment of BSIs secondary to Enterobacter, Serratia, or Citrobacter species compared to other antimicrobial agents
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