3,949 research outputs found
Use of CUDA for the Continuous Space Language Model
The training phase of the Continuous Space Language Model (CSLM) was implemented in the NVIDIA hardware/software architecture Compute Unified Device Architecture (CUDA). Implementation was accomplished using a combination of CUBLAS library routines and CUDA kernel calls on three different CUDA enabled devices of varying compute capability and a time savings over the traditional CPU approach demonstrated
Vaginal Microbicides: Detecting Toxicities in Vivo that Paradoxically Increase Pathogen Transmission
BACKGROUND: Microbicides must protect against STD pathogens without causing unacceptable toxic effects. Microbicides based on nonoxynol-9 (N9) and other detergents disrupt sperm, HSV and HIV membranes, and these agents are effective contraceptives. But paradoxically N9 fails to protect women against HIV and other STD pathogens, most likely because it causes toxic effects that increase susceptibility. The mouse HSV-2 vaginal transmission model reported here: (a) Directly tests for toxic effects that increase susceptibility to HSV-2, (b) Determines in vivo whether a microbicide can protect against HSV-2 transmission without causing toxicities that increase susceptibility, and (c) Identifies those toxic effects that best correlate with the increased HSV susceptibility. METHODS: Susceptibility was evaluated in progestin-treated mice by delivering a low-dose viral inoculum (0.1 ID50) at various times after delivering the candidate microbicide to detect whether the candidate increased the fraction of mice infected. Ten agents were tested – five detergents: nonionic (N9), cationic (benzalkonium chloride, BZK), anionic (sodium dodecylsulfate, SDS), the pair of detergents in C31G (C14AO and C16B); one surface active agent (chlorhexidine); two non-detergents (BufferGel®, and sulfonated polystyrene, SPS); and HEC placebo gel (hydroxyethylcellulose). Toxic effects were evaluated by histology, uptake of a 'dead cell' dye, colposcopy, enumeration of vaginal macrophages, and measurement of inflammatory cytokines. RESULTS: A single dose of N9 protected against HSV-2 for a few minutes but then rapidly increased susceptibility, which reached maximum at 12 hours. When applied at the minimal concentration needed for brief partial protection, all five detergents caused a subsequent increase in susceptibility at 12 hours of ~20–30-fold. Surprisingly, colposcopy failed to detect visible sign of the N9 toxic effect that increased susceptibility at 12 hours. Toxic effects that occurred contemporaneously with increased susceptibility were rapid exfoliation and re-growth of epithelial cell layers, entry of macrophages into the vaginal lumen, and release of one or more inflammatory cytokines (Il-1β, KC, MIP 1α, RANTES). The non-detergent microbicides and HEC placebo caused no significant increase in susceptibility or toxic effects. CONCLUSION: This mouse HSV-2 model provides a sensitive method to detect microbicide-induced toxicities that increase susceptibility to infection. In this model, there was no concentration at which detergents provided protection without significantly increasing susceptibility.JHU Woodrow Wilson Fellowship; National Institutes of Health (Program Project A1 45967
Exposure of a 23F serotype strain of <i>Streptococcus pneumoniae</i> to cigarette smoke condensate is associated with selective upregulation of genes encoding the two-component regulatory system 11 (TCS11)
Alterations in whole genome expression profiles following exposure of the pneumococcus (strain 172, serotype 23F) to cigarette smoke condensate (160 μg/mL) for 15 and 60 min have been determined using the TIGR4 DNA microarray chip. Exposure to CSC resulted in the significant (P < 0.014–0.0006) upregulation of the genes encoding the two-component regulatory system 11 (TCS11), consisting of the sensor kinase, hk11, and its cognate response regulator, rr11, in the setting of increased biofilm formation. These effects of cigarette smoke on the pneumococcus may contribute to colonization of the airways by this microbial pathogen
Whitewater Sound Dependence on Discharge and Wave Configuration at an Adjustable Wave Feature
Stream acoustics has been proposed as a means of monitoring discharge and wave hazards from outside the stream channel. To better understand the dependence of sound on discharge and wave characteristics, this study analyzes discharge and infrasound data from an artificial wave feature which is adjusted to accommodate daily changes in recreational use and seasonal changes in irrigation demand. Monitorable sound is only observed when discharge exceeds ∼35 m3/s, and even above that threshold the sound-discharge relationship is non-linear and inconsistent. When sound is observed, it shows consistent dependence on wave type within a given year, but the direction of this dependence varies among the 3 years studied (2016, 2021, and 2022). These findings support previous research that establishes discharge and stream morphology as relevant controls on stream acoustics and highlights the complex, combined effects of these variables
Exploring Linkage of Quality Management to Innovation
In many business sectors today, focus on quality as a competitive tool is being replaced by a focus on innovation. Research exploring connections between quality management, innovation, and company performance suggests that quality is ‘necessary but insufficient’ in business today. In short, managers need to know how to adapt their quality management practices to achieve innovation performance in addition to quality performance. West coast U.S. forest products manufacturers were surveyed about their quality management practices and performance with respect to both quality and innovation. Results were analyzed to identify two categories of high-performing firms: those achieving primarily quality outcomes and those achieving both quality and innovation outcomes. Executives from firms in each category were interviewed to provide detail on management practices. Results suggest firms must first change how they view innovation; firms that were primarily focused on quality rather than innovation viewed innovation as an end rather than the means to some other business goal. The most significant finding is related to how firms interact with customers – firms focused on innovation proactively seek to identify and meet customers’ needs whereas quality-focused firms primarily emphasize reacting to customer complaints. Findings suggest several areas where managers can focus to improve innovation performance
An investigation of the degradation of Fluorinated Ethylene Propylene (FEP) copolymer thermal blanketing materials aboard LDEF in the laboratory
Samples of fluorinated ethylene propylene copolymer thermal blanketing material, recovered from the Long Duration Exposure Facility (LDEF), were investigated to determine the nature and the extent of degradation due to exposure to the low-Earth-orbit environment. Samples recovered from the ram-facing direction of LDEF, which received vacuum-ultraviolet (VUV) radiation and atomic-oxygen impingement, and samples from the trailing edge, which received almost exclusively VUV exposure, were investigated by scanning electron microscopy and atomic force microscopy. The most significant result of this investigation was found on samples that received only VUV exposure. These samples possessed a hard, embrittled surface layer that was absent from the atomic-oxygen exposed sample and from unexposed control samples. This surface layer is believed to be responsible for the 'synergistic' effect between VUV and atomic oxygen. Overall, the investigation revealed dramatically different morphologies for the two samples. The sample receiving both atomic-oxygen and VUV exposure was deeply eroded and had a characteristic 'rolling' surface morphology, while the sample that received only VUV exposure showed mild erosion and a surface morphology characterized by sharp high-frequency peaks. The morphologies observed in the LDEF samples, including the embrittled surface layer, were successfully duplicated in the laboratory
A Benefit-Cost Analysis of the Tulsa Universal Pre-K Program
In this paper, benefits and costs are estimated for a universal pre-K program, provided by Tulsa Public Schools. Benefits are derived from estimated effects of Tulsa pre-K on retention by grade 9. Retention effects are projected to dollar benefits from future earnings increases and crime reductions. Based on these estimates, Tulsa pre-K has benefits exceeding costs by about 2-to-1. This benefit cost ratio is far less than the benefit-cost ratios (ranging from 8-to-1 to 16-to-1) for more targeted and intensive pre-K programs from the 1970s and 80s, such as Perry Preschool and the Chicago Child-Parent Center (CPC) program. Comparing benefit-cost results from different studies suggests that our more modest estimates are due to two factors: 1) smaller percentage effects of pre-K on future earnings and crime in Tulsa than in Perry and CPC, and 2) smaller baseline crime rates in Tulsa than in the Perry and CPC comparison groups
A Benefit-Cost Analysis of the Tulsa Universal Pre-K Program
In this paper, benefits and costs are estimated for a universal pre-K program, provided by Tulsa Public Schools. Benefits are derived from estimated effects of Tulsa pre-K on retention by grade 9. Retention effects are projected to dollar benefits from future earnings increases and crime reductions. Based on these estimates, Tulsa pre-K has benefits exceeding costs by about 2-to-1. This benefit cost ratio is far less than the benefit-cost ratios (ranging from 8-to-1 to 16-to-1) for more targeted and intensive pre-K programs from the 1970s and 80s, such as Perry Preschool and the Chicago Child-Parent Center (CPC) program. Comparing benefit-cost results from different studies suggests that our more modest estimates are due to two factors: 1) smaller percentage effects of pre-K on future earnings and crime in Tulsa than in Perry and CPC, and 2) smaller baseline crime rates in Tulsa than in the Perry and CPC comparison groups
Salt Dissolution and Surface Subsidence in Central Kansas: A Seismic Investigation of the Anthropogenic and Natural Origin Models
Gradual subsidence in the Punkin Center study area, northeast Reno County, Kansas, has resulted in ponding of surface waters, abandonment of at least one oil well, and damage to county roads. Because the Punkin Center area is within the Burrton oil field and is underlain by the Hutchinson Salt Member, surface subsidence historically has been attributed to salt dissolution of anthropogenic origin. Subsidence that occurred significant distances from any known well sites has been attributed to unrecorded abandoned wells or complex asymmetric patterns of salt dissolution that originated at a drillhole.
To ascertain the validity of the widely accepted anthropogenic salt-dissolution model, a 4-km seismic reflection profile was acquired along an east-west-oriented county road adjacent to an abandoned oil well. The expectation was that the residual Hutchinson Salt Member would be anomalously thin where maximum recorded surface subsidence occurred and thicker elsewhere. Contrary to expectations, the residual Hutchinson Salt Member is relatively thick (20-30 m) below areas of significant recent surface subsidence. There is no evidence of recent surface subsidence at those locations along the seismic profile where the rock salt has been totally leached. At these sites dissolution and subsidence is interpreted to predate European settlement in Kansas and to be of natural origin.
The presence of dissolution and subsidence features related to natural processes has implications for developing an understanding of the potentially complex relationship between anthropogenic activities and pre-existing geologic conditions. Sinkhole development is apparently a natural and expected process along an irregular salt dissolution front. The geometry of this front may be influenced strongly by geologic factors (e.g., fracture patterns and facies distribution). The results are that not all modern sinkhole development has a clear-cut anthropogenic cause, and the potential for adverse impact resulting from anthropogenic activities will be influenced strongly by pre-existing geologic conditions. Efficient management decisions along the dissolution front related to well location and well-site practices should take into account natural processes that previously have and will continue to have an effect on salt dissolution and surface subsidence
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