High Transmissibility During Early HIV Infection Among Men Who Have Sex With Men-San Francisco, California.

We estimate the relative transmission rate in early versus later infection among men who have sex with men (MSM) in San Francisco, California, by studying the characteristics of a sample of transmitters, recruited through newly diagnosed, recently infected MSM between 1996 and 2009. Of 36 transmitters identified, 9 were determined on the basis of testing history and serologic testing to have been recently infected. The unadjusted odds ratio of transmitting during early infection was 15.2 (95% confidence interval [CI], 6.3–33.4; P < .001); the odds ratio was 8.9 (95% CI, 4.1–19.4) after adjustment for self-reported antiretroviral treatment. This high transmissibility could be due to both high infectiousness and high rates of sex partner change or concurrent partnerships

Modeling the Abrasion and Transport of Mud Aggregates in the James River, Virginia

Recent research has found that dredged material placed in rivers and estuaries tends to erode as aggregated particles as opposed to individual particles. These aggregated particles, or mud aggregates, are then observed to undergo abrasion during bedload transport. Testing of these mud aggregates in an aggregate tumbler and a flume suggested that the aggregates could only travel a few kilometers before losing over approximately 90% of their effective diameter due to abrasion (Perkey et al., 2019). Current sediment transport models do not simulate the process of abrasion. An aggregate abrasion routine was derived from existing research and then added to a one-dimensional (1-D) sediment transport model developed during this research and to an existing three-dimensional (3-D) sediment transport model. The abrasion routine was developed to simulate the abrasion of mud aggregates that were being transported as bedload. Instead of changing the diameter of the aggregate as it is transported and undergoes abrasion, abrasion was simulated by transferring mass from aggregates moving as bedload to the next smallest aggregate size class as well as to a 20 µm aggregate size class representing the byproduct of abrasion. As the 1-D and 3-D sediment transport models use a Eulerian grid, transferring mass between size classes allowed the abrasion routine to be used in a Eulerian grid, as opposed to using a Lagrangian time frame where the diameter of each individual aggregate would decrease while being transported as bedload. Using the 1-D sediment transport model, the simulations involving the abrasion routine increased the total mass of suspended load of the mud aggregates by 0.5% to 1% and decreased the total bedload mass of the aggregates by 0.25% to 0.5% over an hourlong simulation in a closed system. Using a 3-D sediment transport model of the James River, the inclusion of the abrasion routine to the simulation resulted in the bedload concentrations of the two largest mud aggregate size classes, analyzed at 1.2 km and 2.2 km away from the center of area of the placement site, to be less than 5% of the bedload concentrations given by the model simulation without abrasion when compared at each time step during a 15-day simulation. This indicated that the mud aggregates in bedload were losing over 95% of their mass within the first few kilometers of transport due to abrasion, which was expected based on prior research by Perkey et al. (2019). In the portions of the navigation channel that were analyzed, all within 11 km of the placement site, the inclusion of the abrasion routine to the simulation resulted in approximately a 55% to 75% decrease in total mass of mud aggregates in the sediment bed compared to the simulation without abrasion when using a 15-day, 3-D sediment transport model of the James River. This was due to the abrasion routine transferring mass from larger mud aggregates in bedload to smaller mud aggregates, primarily in suspension, that were less likely to deposit

Students’ Perceptions and Stigma Toward Those with Intellectual and Physical Disabilities

Students’ Perceptions and Stigma Toward Those with Intellectual and Physical Disabilities BACKGROUND: Previous research has shown that there is a negative impact on those who are labeled as having an intellectual or physical disability (Green, Davis, Karshmer, Marsh, & Straight, 2005). The purpose of this research was to learn more about the stigma against those with disabilities and how one can cope with this stigma. METHODS: The subjects of this study were 80 General Psychology students. Participants were randomly assigned to one of four conditions, which differed in which vignette received. The four vignettes described individuals with the disabilities of (1) Autism, (2) Attention Deficit Hyperactivity Disorder, (3) Paralysis, and (4) Blindness. After reading, participants were given three questions to ensure that they had read carefully. Participants then completed the 17-item Community Living Attitudes Scale (CLAS), which measures general attitudes towards disabilities. RESULTS AND DISCUSSION: A Chi-square test was used to test the hypothesis that participants would differ in their ability to recognize different disabilities. Indeed, the data shows that participants incorrectly diagnosed Autism and Blindness more frequently than Attention Deficit Disorder and paralysis, Χ2=(3, N=80) = 15.075, p\u3c .01. Additionally, One-Way ANOVAs were run to examine differences in the CLAS scales between the four vignettes. Results indicate that participants differed in their ability to recognize different disorders. Additionally, results indicated varying levels of Empowerment, Exclusion, Similarity, and Sheltering between conditions. This indicates that stigmas may be diminishing. Future research should further examine why stigma occurs against these and other disabilities. Results will be discussed in more detail during the presentation. Keywords: Attitudes, Physical Disabilities, Intellectual Disabilities, Stigm

Overview of UK 101: Academic Orientation Course

A review of UK 101, Academic Orientation Course , and its impact on retention and graduation rates at the University of Kentucky (UK). The study includes charts showing the differences in retention and graduation rates over time from 2001 to 2013. It also explores key issues and suggested next steps within the context of UK\u27s efforts to raise the number of first-year students and the use of the shared curriculum by colleges for their specialized sections to meet the needs of their new students. This white paper is the result of collaboration between many units at UK together with the Division of Undergraduate Education, including the Dean of Students Office in Student Affairs and the UK Academic Technologies Team

Simple approximations for epidemics with exponential and fixed infectious periods

Analytical approximations have generated many insights into the dynamics of epidemics, but there is only one well-known approximation which describes the dynamics of the whole epidemic. In addition, most of the well-known approximations for different aspects of the dynamics are for the classic susceptible–infected–recovered model, in which the infectious period is exponentially distributed. Whilst this assumption is useful, it is somewhat unrealistic. Equally reasonable assumptions are that the infectious period is finite and fixed or that there is a distribution of infectious periods centred round a nonzero mean. We investigate the effect of these different assumptions on the dynamics of the epidemic by deriving approximations to the whole epidemic curve. We show how the well-known sech-squared approximation for the infective population in ‘weak’ epidemics (where the basic reproduction rate R0≈1) can be extended to the case of an arbitrary distribution of infectious periods having finite second moment, including as examples fixed and gamma-distributed infectious periods. Further, we show how to approximate the time course of a ‘strong’ epidemic, where R0≫1, demonstrating the importance of estimating the infectious period distribution early in an epidemic

The dynamics of Ascaris lumbricoides infections

The Anderson–May model of human parasite infections and specifically that for the intestinal worm Ascaris lumbricoides is reconsidered, with a view to deriving the observed characteristic negative binomial distribution which is frequently found in human communities. The means to obtaining this result lies in reformulating the continuous Anderson–May model as a stochastic process involving two essential populations, the density of mature worms in the gut, and the density of mature eggs in the environment. The resulting partial differential equation for the generating function of the joint probability distribution of eggs and worms can be partially solved in the appropriate limit where the worm lifetime is much greater than that of the mature eggs in the environment. Allowing for a mean field nonlinearity, and for egg immigration from neighbouring communities, a negative binomial worm distribution can be predicted, whose parameters are determined by those in the continuous Anderson–May model; this result assumes no variability in predisposition to the infection

Design, processing, and testing of LSI arrays for space station

The development of a low power, high performance MOS 256-bit random assess memory with beam leads is discussed. Beam lead process development on silicon-on-sapphire (SOS) is also discussed, and initial electrical results on beam lead SOS TA5388 devices are presented. A comparison of the beam leaded 256-bit RAM (TA6567) layout is made with the non-beam leaded version (TA6473)

Quantifying engineered nanomaterial toxicity: comparison of common cytotoxicity and gene expression measurements

BACKGROUND: When evaluating the toxicity of engineered nanomaterials (ENMS) it is important to use multiple bioassays based on different mechanisms of action. In this regard we evaluated the use of gene expression and common cytotoxicity measurements using as test materials, two selected nanoparticles with known differences in toxicity, 5 nm mercaptoundecanoic acid (MUA)-capped InP and CdSe quantum dots (QDs). We tested the effects of these QDs at concentrations ranging from 0.5 to 160 µg/mL on cultured normal human bronchial epithelial (NHBE) cells using four common cytotoxicity assays: the dichlorofluorescein assay for reactive oxygen species (ROS), the lactate dehydrogenase assay for membrane viability (LDH), the mitochondrial dehydrogenase assay for mitochondrial function, and the Comet assay for DNA strand breaks. RESULTS: The cytotoxicity assays showed similar trends when exposed to nanoparticles for 24 h at 80 µg/mL with a threefold increase in ROS with exposure to CdSe QDs compared to an insignificant change in ROS levels after exposure to InP QDs, a twofold increase in the LDH necrosis assay in NHBE cells with exposure to CdSe QDs compared to a 50% decrease for InP QDs, a 60% decrease in the mitochondrial function assay upon exposure to CdSe QDs compared to a minimal increase in the case of InP and significant DNA strand breaks after exposure to CdSe QDs compared to no significant DNA strand breaks with InP. High-throughput quantitative real-time polymerase chain reaction (qRT-PCR) data for cells exposed for 6 h at a concentration of 80 µg/mL were consistent with the cytotoxicity assays showing major differences in DNA damage, DNA repair and mitochondrial function gene regulatory responses to the CdSe and InP QDs. The BRCA2, CYP1A1, CYP1B1, CDK1, SFN and VEGFA genes were observed to be upregulated specifically from increased CdSe exposure and suggests their possible utility as biomarkers for toxicity. CONCLUSIONS: This study can serve as a model for comparing traditional cytotoxicity assays and gene expression measurements and to determine candidate biomarkers for assessing the biocompatibility of ENMs.1R01GM84702-01 - National Institute of General Medical Science

Treatment and outcomes in necrotising autoimmune myopathy: an australian perspective

Necrotising Autoimmune Myopathy (NAM) presents as a subacute proximal myopathy with high creatine kinase levels. It is associated with statin exposure, 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) antibody, connective tissue diseases, signal recognition particle (SRP) antibody and malignancy. This case series presents our Western Australian NAM patient cohort: comparing the subgroup presentations, biopsy appearance and treatment outcomes. We retrospectively collected data on patients diagnosed with NAM at the Western Australian Neuroscience Research Institute between the years 2000 and 2015. We identified 20 patients with Necrotising Autoimmune Myopathy: 14 with anti-HMGCR antibodies; two with anti-SRP antibodies; three with connective tissue disease; two as yet unspecified. Median creatine kinase level was 6047units/L (range 1000–17000). The statin naïve patients with HMGCR antibodies and patients with SRP antibodies were the most severely affected subgroups, with higher creatine kinase levels, and were more resistant to immunotherapy. Two or more immunotherapy agents were required in 90%; eight patients required IVIG and rituximab. Steroid weaning commonly precipitated relapses. Four patients had complete remission, and the remaining patients still require immunotherapy. Necrotising Autoimmune Myopathy is a potentially treatable myopathy, which can be precipitated by statin therapy and requires early, aggressive immunotherapy, usually requiring multiple steroid sparing agents for successful steroid weaning

Temporal diversification of Central American cichlids

<p>Abstract</p> <p>Background</p> <p>Cichlid fishes are classic examples of adaptive radiation because of their putative tendency to explosively diversify after invading novel environments. To examine whether ecological opportunity increased diversification (speciation minus extinction) early in a species-rich cichlid radiation, we determined if Heroine cichlids experienced a burst of diversification following their invasion of Central America.</p> <p>Results</p> <p>We first reconstructed the Heroine phylogeny and determined the basal node to use as the root of Central American Heroine diversification. We then examined the influence of incomplete taxon sampling on this group's diversification patterns. First, we added missing species randomly to the phylogeny and assessed deviations from a constant rate of lineage accumulation. Using a range of species numbers, we failed to recover significant deviations from a pure-birth process and found little support for an early burst of diversification. Then, we examined patterns of lineage accumulation as nodes were increasingly truncated. We assumed that as we removed more recently diverged lineages that sampling would become more complete thereby increasing the power to detect deviations from a pure-birth model. However, truncation of nodes provided even less support for an early burst of diversification.</p> <p>Conclusions</p> <p>Contrary to expectations, our analyses suggest Heroine cichlids did not undergo a burst of diversification when they invaded from South America. Throughout their history in Central America, Heroine cichlids appear to have diversified at a constant rate.</p