78 research outputs found
Abstract This study applied the Model of Acidification
of Groundwater in Catchments (MAGIC) to estimate the sensitivity of 66 watersheds in the Southern Blue Ridge Province of the Southern Appalachian Mountains, United States, to changes in atmospheric sulfur (S) deposition. MAGIC predicted that stream acid neutralizing capacity (ANC) values were above 20 μeq/L in all modeled watersheds in 1860. Hindcast simulations suggested that the media
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Estimating vertebrate, benthic macroinvertebrate, and diatom taxa richness in raftable Pacific Northwest rivers for bioassessment purposes
The number of sites sampled must be considered when determining the effort necessary for adequately assessing taxa richness in an ecosystem for bioassessment purposes; however, there have been few studies concerning the number of sites necessary for bioassessment of large rivers. We evaluated the effect of sample size (i.e., number of sites) necessary to collect vertebrate (fish and aquatic amphibians), macroinvertebrate, and diatom taxa from seven large rivers in Oregon and Washington, USA during the summers of 2006–2008. We used Monte Carlo simulation to determine the number of sites needed to collect 90–95% of the taxa 75–95% of the time from 20 randomly located sites on each river. The river wetted widths varied from 27.8 to 126.0 m, mean substrate size varied from 1 to 10 cm, and mainstem distances sampled varied from 87 to 254 km. We sampled vertebrates at each site (i.e., 50 times the mean wetted channel width) by nearshore-raft electrofishing. We sampled benthic macroinvertebrates nearshore through the use of a 500-μm mesh kick net at 11 systematic stations. From each site composite sample, we identified a target of 500 macroinvertebrate individuals to the lowest possible taxon, usually genus. We sampled benthic diatoms nearshore at the same 11 stations from a 12-cm² area. At each station, we sucked diatoms from soft substrate into a 60-ml syringe or brushed them off a rock and rinsed them with river water into the same jar. We counted a minimum of 600 valves at 1,000× magnification for each site. We collected 120–211 diatom taxa, 98–128 macroinvertebrate taxa, and 14–33 vertebrate species per river. To collect 90-95% of the taxa 75-95% of the time that were collected at 20 sites, it was necessary to sample 11–16 randomly distributed sites for vertebrates, 13–17 sites for macroinvertebrates, and 16–18 sites for diatoms. We conclude that 12–16 randomly distributed sites are needed for cost-efficient sampling of vertebrate richness in the main stems of our study rivers, but 20 sites markedly underestimates the species richness of benthic macroinvertebrates and diatoms in those rivers.KEYWORDS: Fish, Benthos, Oregon, Washington, Large unwadeable rivers, Sampling effort, Periphyto
Eff ectiveness of 4% chlorhexidine umbilical cord care on neonatal mortality in Southern Province, Zambia (ZamCAT): a cluster-randomised controlled trial
Background Chlorhexidine umbilical cord washes reduce neonatal mortality in south Asian populations with high
neonatal mortality rates and predominantly home-based deliveries. No data exist for sub-Saharan African populations
with lower neonatal mortality rates or mostly facility-based deliveries. We compared the eff ect of chlorhexidine with
dry cord care on neonatal mortality rates in Zambia.
Methods We undertook a cluster-randomised controlled trial in Southern Province, Zambia, with 90 health facilitybased
clusters. We enrolled women who were in their second or third trimester of pregnancy, aged at least 15 years,
and who would remain in the catchment area for follow-up of 28 days post-partum. Newborn babies received clean
dry cord care (control) or topical application of 10 mL of a 4% chlorhexidine solution once per day until 3 days after
cord drop (intervention), according to cluster assignment. We used stratifi ed, restricted randomisation to divide
clusters into urban or two rural groups (located <40 km or ≥40 km to referral facility), and randomly assigned clusters
(1:1) to use intervention (n=45) or control treatment (n=45). Sites, participants, and fi eld monitors were aware of their
study assignment. The primary outcomes were all-cause neonatal mortality within 28 days post-partum and all-cause
neonatal mortality within 28 days post-partum among babies who survived the fi rst 24 h of life. Analysis was by
intention to treat. Neonatal mortality rate was compared with generalised estimating equations. This study is
registered at ClinicalTrials.gov (NCT01241318).
Findings From Feb 15, 2011, to Jan 30, 2013, we screened 42 356 pregnant women and enrolled 39 679 women (mean
436·2 per cluster [SD 65·3]), who had 37 856 livebirths and 723 stillbirths; 63·8% of deliveries were facility-based. Of
livebirths, 18 450 (99·7%) newborn babies in the chlorhexidine group and 19 308 (99·8%) newborn babies in the dry cord
care group were followed up to day 28 or death. 16 660 (90·0%) infants in the chlorhexidine group had chlorhexidine
applied within 24 h of birth. We found no signifi cant diff erence in neonatal mortality rate between the chlorhexidine
group (15·2 deaths per 1000 livebirths) and the dry cord care group (13·6 deaths per 1000 livebirths; risk ratio [RR] 1·12,
95% CI 0·88–1·44). Eliminating day 0 deaths yielded similar fi ndings (RR 1·12, 95% CI 0·86–1·47).
Interpretation Despite substantial reductions previously reported in south Asia, chlorhexidine cord applications did not
signifi cantly reduce neonatal mortality rates in Zambia. Chlorhexidine cord applications do not seem to provide clear
benefi ts for newborn babies in settings with predominantly facility-based deliveries and lower (<30 deaths per
1000 livebirths) neonatal mortality rates
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Perturbed myoepithelial cell differentiation in BRCA mutation carriers and in ductal carcinoma in situ.
Myoepithelial cells play key roles in normal mammary gland development and in limiting pre-invasive to invasive breast tumor progression, yet their differentiation and perturbation in ductal carcinoma in situ (DCIS) are poorly understood. Here, we investigated myoepithelial cells in normal breast tissues of BRCA1 and BRCA2 germline mutation carriers and in non-carrier controls, and in sporadic DCIS. We found that in the normal breast of non-carriers, myoepithelial cells frequently co-express the p63 and TCF7 transcription factors and that p63 and TCF7 show overlapping chromatin peaks associated with differentiated myoepithelium-specific genes. In contrast, in normal breast tissues of BRCA1 mutation carriers the frequency of p63+TCF7+ myoepithelial cells is significantly decreased and p63 and TCF7 chromatin peaks do not overlap. These myoepithelial perturbations in normal breast tissues of BRCA1 germline mutation carriers may play a role in their higher risk of breast cancer. The fraction of p63+TCF7+ myoepithelial cells is also significantly decreased in DCIS, which may be associated with invasive progression
Militarization, human rights violations and community responses as determinants of health in southeastern Myanmar: results of a cluster survey
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2010 Seed production research at Oregon State University, USDA-ARS cooperating
Pathology Case Study: Progressive Dyspnea and Bilteral Pulmonary Infiltrates
This is a case study presented by the University of Pittsburgh Department of Pathology in which a woman died two days after presenting with mass lesions on her lungs. Visitors are given both the microscopic and gross descriptions, including images, and are given the opportunity to diagnose the patient. This is an excellent resource for students in the health sciences to familiarize themselves with using patient history and laboratory results to diagnose disease. It is also a helpful site for educators to use to introduce or test student learning in pulmonary pathology
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