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Testing Reliable Distributed Applications Through Simulated Events
There are many distributed applications that incorporate application-specific reliability algorithms which operate on top of general purpose networking, operating system and programming language facilities. We present a framework for application-level reliability testing suitable for a wide range of distributed applications, and describe how we've applied it to one particular application, Mercury, a distributed, multi-user programming environment
Label-free imaging of thick tissue at 1550nm using a femtosecond optical parametric generator
We have developed a simple wavelength tunable optical parametric generator (OPG), emitting broad band ultrashort pulses with peak wavelengths at 1530-1790 nm, for nonlinear label-free microscopy. The OPG consists of a periodically poled lithium niobate crystal, pumped at 1064 nm by a ultrafast Yb:fiber laser with high pulse energy. We demonstrate that this OPG can be used for label-free imaging, by third harmonic generation, of nuclei of brain cells and blood vessels in a >150 µm thick brain tissue section, with very little decay of intensity with imaging depth and no visible damage to the tissue at an incident average power of 15 mW
Earliest Porotic Hyperostosis on a 1.5-Million-year-old Hominin, olduvai gorge, Tanzania.
Meat-eating was an important factor affecting early hominin brain expansion, social organization and geographic movement. Stone tool butchery marks on ungulate fossils in several African archaeological assemblages demonstrate a significant level of carnivory by Pleistocene hominins, but the discovery at Olduvai Gorge of a child's pathological cranial fragments indicates that some hominins probably experienced scarcity of animal foods during various stages of their life histories. The child's parietal fragments, excavated from 1.5-million-year-old sediments, show porotic hyperostosis, a pathology associated with anemia. Nutritional deficiencies, including anemia, are most common at weaning, when children lose passive immunity received through their mothers' milk. Our results suggest, alternatively, that (1) the developmentally disruptive potential of weaning reached far beyond sedentary Holocene food-producing societies and into the early Pleistocene, or that (2) a hominin mother's meat-deficient diet negatively altered the nutritional content of her breast milk to the extent that her nursing child ultimately died from malnourishment. Either way, this discovery highlights that by at least 1.5 million years ago early human physiology was already adapted to a diet that included the regular consumption of meat
Premenopausal endogenous oestrogen levels and breast cancer risk: a meta-analysis.
BACKGROUND: Many of the established risk factors for breast cancer implicate circulating hormone levels in the aetiology of the disease. Increased levels of postmenopausal endogenous oestradiol (E2) have been found to increase the risk of breast cancer, but no such association has been confirmed in premenopausal women. We carried out a meta-analysis to summarise the available evidence in women before the menopause. METHODS: We identified seven prospective studies of premenopausal endogenous E2 and breast cancer risk, including 693 breast cancer cases. From each study we extracted odds ratios of breast cancer between quantiles of endogenous E2, or for unit or s.d. increases in (log transformed) E2, or (where odds ratios were unavailable) summary statistics for the distributions of E2 in breast cancer cases and unaffected controls. Estimates for a doubling of endogenous E2 were obtained from these extracted estimates, and random-effect meta-analysis was used to obtain a pooled estimate across the studies. RESULTS: Overall, we found weak evidence of a positive association between circulating E2 levels and the risk of breast cancer, with a doubling of E2 associated with an odds ratio of 1.10 (95% CI: 0.96, 1.27). CONCLUSION: Our findings are consistent with the hypothesis of a positive association between premenopausal endogenous E2 and breast cancer risk
The APOKASC Catalog: An Asteroseismic and Spectroscopic Joint Survey of Targets in the Kepler Fields
We present the first APOKASC catalog of spectroscopic and asteroseismic
properties of 1916 red giants observed in the Kepler fields. The spectroscopic
parameters provided from the Apache Point Observatory Galactic Evolution
Experiment project are complemented with asteroseismic surface gravities,
masses, radii, and mean densities determined by members of the Kepler
Asteroseismology Science Consortium. We assess both random and systematic
sources of error and include a discussion of sample selection for giants in the
Kepler fields. Total uncertainties in the main catalog properties are of order
80 K in Teff , 0.06 dex in [M/H], 0.014 dex in log g, and 12% and 5% in mass
and radius, respectively; these reflect a combination of systematic and random
errors. Asteroseismic surface gravities are substantially more precise and
accurate than spectroscopic ones, and we find good agreement between their mean
values and the calibrated spectroscopic surface gravities. There are, however,
systematic underlying trends with Teff and log g. Our effective temperature
scale is between 0-200 K cooler than that expected from the Infrared Flux
Method, depending on the adopted extinction map, which provides evidence for a
lower value on average than that inferred for the Kepler Input Catalog (KIC).
We find a reasonable correspondence between the photometric KIC and
spectroscopic APOKASC metallicity scales, with increased dispersion in KIC
metallicities as the absolute metal abundance decreases, and offsets in Teff
and log g consistent with those derived in the literature. We present mean
fitting relations between APOKASC and KIC observables and discuss future
prospects, strengths, and limitations of the catalog data.Comment: 49 pages. ApJSupp, in press. Full machine-readable ascii files
available under ancillary data. Categories: Kepler targets, asteroseismology,
large spectroscopic survey
TRIM5alpha Restricts Flavivirus Replication by Targeting the Viral Protease for Proteasomal Degradation
Tripartite motif-containing protein 5alpha (TRIM5alpha) is a cellular antiviral restriction factor that prevents early events in retrovirus replication. The activity of TRIM5alpha is thought to be limited to retroviruses as a result of highly specific interactions with capsid lattices. In contrast to this current understanding, we show that both human and rhesus macaque TRIM5alpha suppress replication of specific flaviviruses. Multiple viruses in the tick-borne encephalitis complex are sensitive to TRIM5alpha-dependent restriction, but mosquito-borne flaviviruses, including yellow fever, dengue, and Zika viruses, are resistant. TRIM5alpha suppresses replication by binding to the viral protease NS2B/3 to promote its K48-linked ubiquitination and proteasomal degradation. Importantly, TRIM5alpha contributes to the antiviral function of IFN-I against sensitive flaviviruses in human cells. Thus, TRIM5alpha possesses remarkable plasticity in the recognition of diverse virus families, with the potential to influence human susceptibility to emerging flaviviruses of global concern
Oral pre-exposure prophylaxis uptake, adherence, and adverse events among South African men who have sex with men and transgender women
DATA AVAILABILITY : Data that support the findings may contain identifying or sensitive patient information. To preserve participant confidentiality, these data cannot be shared publicly. The principal investigator of this study, P.S.S. (pssulli@emory. edu), can be contacted with requests to access these data.BACKGROUND : HIV prevention programmes that include pre-exposure prophylaxis (PrEP) for
men who have sex with men (MSM) and transgender women (TGW) in South Africa have not
been widely implemented.
OBJECTIVES : The authors examined oral PrEP uptake, adherence, and adverse events among
HIV-uninfected MSM and TGW to inform intervention acceptability and feasibility.
METHOD : In 2015, MSM and TGW in two South African cities were offered a comprehensive
package of HIV prevention services, including daily oral PrEP, and were followed for one year.
Different models of PrEP delivery were used at each site. Adherence was measured using
self-report and pill-count data and tenofovir-diphosphate (TFV-DP) concentrations.
RESULTS : Among 135 participants who were eligible for PrEP, 82 (61%) initiated PrEP, of whom
67 (82%) were on PrEP at study end. Participants were on PrEP for a median of 294 out of 314.5
possible days (93% protected days). The median time from PrEP initiation to discontinuation
or study end was 305 days (interquartile range: 232–325 days). Across the follow-up time
points, 57% – 72% of participants self-reported taking protective levels of PrEP and 59% – 74%
were adherent to PrEP as indicated by pill counts. Fewer (≤ 18%) achieved protective TFV-DP
concentrations of ≥ 700 fmol/punch in dried blood spots. Side effects, while typically mild,
were the most commonly cited reason by participants for early PrEP discontinuation.
CONCLUSION : Many MSM and TGW initiated and maintained PrEP, demonstrating that PrEP
can be successfully delivered to South African MSM and TGW in diverse programmatic
contexts. Biologic adherence measures suggest MSM and TGW may experience challenges
taking PrEP regularly. Counselling for coping with side effects and motivating daily pill taking
is recommended to support South African MSM and TGW in achieving protection with PrEP.The Center for AIDS Research at Emory University and the National Institute for Allergy and Infectious Diseases.http://www.sajhivmed.org.zaam2023School of Health Systems and Public Health (SHSPH
Sexually transmitted infection screening, prevalence and incidence among South African men and transgender women who have sex with men enrolled in a combination HIV prevention cohort study : the Sibanye Methods for Prevention Packages Programme (MP3) project
INTRODUCTION : Men who have sex with men (MSM) and transgender women (TGW) experience high incidence and prevalence
of sexually transmitted infections (STI), and data are needed to understand risk factors for STIs in these populations. The Sibanye
Health Project was conducted in Cape Town and Port Elizabeth, South Africa from 2015 to 2016 to develop and test a
package of HIV prevention interventions for MSM and TGW. We describe the incidence, prevalence and symptoms of Chlamydia
trachomatis (CT), Neisseria gonorrhea (NG) and syphilis observed during the study.
METHODS : Participants completed HIV testing at baseline. All participants who were HIV negative were followed prospectively.
Additionally, a sample of participants identified as living with HIV at baseline was selected to be followed prospectively so that
the prospective cohort was approximately 20% HIV positive; the remaining participants identified as HIV positive at baseline
were not followed prospectively. Prospective participants were followed for 12 months and returned for clinic-based STI/HIV
testing and assessment of STI symptoms at months 6 and 12. Additional HIV/STI testing visits could be scheduled at participant
request.
RESULTS : Following consent, a total of 292 participants attended a baseline visit (mean age = 26 years), and 201 were enrolled
for the 12-month prospective study. Acceptance of screening for syphilis and urethral NG/CT was near universal, though
acceptance of screening for rectal NG/CT was lower (194/292; 66%). Prevalence of urethral CT and NG at baseline was 10%
(29/289) and 3% (8/288) respectively; incidence of urethral CT and NG was 12.8/100 person-years (PY) and 7.1/100 PY
respectively. Prevalence of rectal CT and NG at baseline was 25% (47/189) and 16% (30/189) respectively; incidence of rectal
CT and NG was 33.4/100 PY and 26.8/100 PY respectively. Prevalence of syphilis at baseline was 17% (45/258) and incidence
was 8.2/100 PY. 91%, 95% and 97% of diagnosed rectal NG/CT, urethral NG/CT and syphilis infections, respectively,
were clinically asymptomatic.
CONCLUSIONS : Prevalence and incidence of urethral and rectal STIs were high among these South African MSM and TGW, and
were similar to rates in other settings in the world. Clinical symptoms from these infections were rare, highlighting limitations
of syndromic surveillance and suggesting the need for presumptive testing and/or treatment to address the STI epidemic
among MSM/TGW in South Africa.Table S1. Acceptance of urethral and syphilis STI screening at
baseline and over 12 months of follow-up among men who
have sex with men and transgender women in Cape Town
and Port Elizabeth, South Africa.Table S2. Rate (per 100 person years), unadjusted rate ratios
(RR), and 95% confidence intervals of urethral and rectal
chlamydia, urethral and rectal gonorrhea, and syphilis among
men who have sex with men (MSM) in Cape Town and Port
Elizabeth, South Africa.The National Institutes of Healthhttp://www.jiasociety.orgam2021School of Health Systems and Public Health (SHSPH
Early disease onset is predicted by a higher genetic risk for lupus and is associated with a more severe phenotype in lupus patients
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94407/1/Webb_2011_Early_disease_onset.pdf165
The IASLC Lung Cancer Staging Project: A Renewed Call to Participation
Over the past two decades, the International Association for the Study of Lung Cancer (IASLC) Staging Project has been a steady source of evidence-based recommendations for the TNM classification for lung cancer published by the Union for International Cancer Control and the American Joint Committee on Cancer. The Staging and Prognostic Factors Committee of the IASLC is now issuing a call for participation in the next phase of the project, which is designed to inform the ninth edition of the TNM classification for lung cancer. Following the case recruitment model for the eighth edition database, volunteer site participants are asked to submit data on patients whose lung cancer was diagnosed between January 1, 2011, and December 31, 2019, to the project by means of a secure, electronic data capture system provided by Cancer Research And Biostatistics in Seattle, Washington. Alternatively, participants may transfer existing data sets. The continued success of the IASLC Staging Project in achieving its objectives will depend on the extent of international participation, the degree to which cases are entered directly into the electronic data capture system, and how closely externally submitted cases conform to the data elements for the project
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