1,353 research outputs found
The Great Salt Lakeās Deep Brine Layer and Its Importance for Mercury Bioaccumulation in Brine Shrimp (Artemia franciscana)
Mercury in water bodies is receiving increased attention due to the toxicity of methylmercury (MeHg). Some authors have suggested that stratified lakes with anoxic hypolimnia experience higher rates of mercury methylation. It is believed that this biochemical pathway is promoted by high levels of H2S and organic matter in the deep layers that fuel sulfateāreducing bacteria that produce methylmercury as a byproduct
Using a Guided-Inquiry Approach To Teach MichaelisāMenten Kinetics
Although kinetics forms a foundational part of the chemical curriculum, laboratory experiences with the subject are often limited and lack relevance to the actual practice of chemistry. Presented is an inquiry-based lab focused on MichaelisāMenten kinetics, implemented in an upper-level, university physical chemistry laboratory. Student learning was assessed over the course of three years via a pre- and post-test scheme that evaluated student understanding of MichaelisāMenten concepts and experimental design. Results indicate improvement in both domains, in line with previous results in the inquiry-based laboratory literature
A Comparative Study on the Impact Evaluation of World Visionās Water, Sanitation and Hygiene Program in Malawi, Mozambique, and Zambia: Analyses Using Lives Saved Tool
Background
According to the World Health Organization, diarrheal disease is the second top killer of children under five years of age (U5), claiming around 760,000 young childrenās lives every year, and 88% of diarrheal disease is attributed to unsafe water supply, inadequate sanitation and hygiene. The humanitarian aid organization, World Vision, launched community-based water, sanitation and hygiene (WASH) project in 76 Area Development Programs (ADPs) for 506,019 target U5 population across Southern Africa Region (SAR): Malawi, Mozambique and Zambia in 2010.
Objective
This study estimated the retrospective health impact of the project between 2010 and 2014 to measure how effectively WASH interventions were implemented.
Method
Computer-based modeling software, Lives Saved Tool (LiST) was utilized for quantitative analysis. The effectiveness and scaled up coverage of five WASH interventions ā improved water source, home water connection, improved sanitation, hand washing with soap, and hygienic disposal of childrenās stools ā were calculated by conducting ADP field visits and analyzing SARās quantitative data.
Result
The significant impact demonstrated that the combined effect of interventions have prevented 989,745 diarrheal cases; this translated to the prevention of 1.96 cases of diarrhea for every U5 and 13% prevention rate for diarrhea. It contributed a 209% mean increase in percentage of U5 lives saved and 15.5% mean decrease in U5 mortality rates. The total number of U5 lives saved from diarrhea was 550.
Conclusion
These results suggest that the project is achieving the organizationās ultimate goal, āEvery child deserves clean water,ā and LiST acted as an effective tool for conducting the quantitative impact assessment of the project at subnational level. To reach the universal coverage by 2020 to prevent all 3 cases of diarrhea per child each year, programming activities must include promotion and facilitation of household-level water connection and regular availability of soap or equivalent, WASH-related health interventions must be fully incorporated into programming, and the existing community-level water treatment sensitization meetings should be leveraged as a forum to bring together additional sector representatives for raising awareness about integrated WASH programming
Age and Growth of Spotted Sand Bass, Paralabrax maculatofasciatus, in Bahia de Los Angeles, Baja California, Mexico, with Age Validation using Otolith Edge Analysis
Age and Growth of Spotted Sand Bass, Paralabrax maculatofasciatus, in Bahia de Los Angeles, Baja California, Mexico, with Age Validation using Otolith Edge Analysis
Spotted sand bass, Paralabrax maculatofasciatus, were collected from Bahia de Los Angeles, Baja California, Mexico covering as wide a size range as possible over four seasons (spring, summer, fall, and winter). Age was estimated and growth parameters calculated from growth zones counted in transverse otolith sections. An otolith edge analysis indicated an opaque growth zone was deposited once per year during the summer, validating the annual periodicity. Spotted sand bass from this region are fast growing with a relatively short life span of up to 11 years. Growth differs from the disjunct Pacific coast population by having a higher growth rate and a shorter longevity
Increased risk for other cancers in individuals with Ewing sarcoma and their relatives.
BackgroundThere are few reports of the association of other cancers with Ewing sarcoma in patients and their relatives. We use a resource combining statewide genealogy and cancer reporting to provide unbiased risks.MethodsUsing a combined genealogy of 2.3 million Utah individuals and the Utah Cancer Registry (UCR), relative risks (RRs) for cancers of other sites were estimated in 143 Ewing sarcoma patients using a Cox proportional hazards model with matched controls; however, risks in relatives were estimated using internal cohort-specific cancer rates in first-, second-, and third-degree relatives.ResultsCancers of three sites (breast, brain, complex genotype/karyotype sarcoma) were observed in excess in Ewing sarcoma patients. No Ewing sarcoma patients were identified among first-, second-, or third-degree relatives of Ewing sarcoma patients. Significantly increased risk for brain, lung/bronchus, female genital, and prostate cancer was observed in first-degree relatives. Significantly increased risks were observed in second-degree relatives for breast cancer, nonmelanoma eye cancer, malignant peripheral nerve sheath cancer, non-Hodgkin lymphoma, and translocation sarcomas. Significantly increased risks for stomach cancer, prostate cancer, and acute lymphocytic leukemia were observed in third-degree relatives.ConclusionsThis analysis of risk for cancer among Ewing sarcoma patients and their relatives indicates evidence for some increased cancer predisposition in this population which can be used to individualize consideration of potential treatment of patients and screening of patients and relatives
Regulation of the PMP22 gene through an intronic enhancer
Successful myelination of the peripheral nervous system depends upon induction of major protein components of myelin, such as Peripheral Myelin Protein 22 (PMP22). Myelin stability is also sensitive to levels of PMP22, as a 1.4 Mb duplication on human chromosome 17, resulting in 3 copies of PMP22, is the most common cause of the peripheral neuropathy, Charcot-Marie-Tooth disease (CMT). The transcription factor Egr2/Krox20 is required for induction of high level expression of Pmp22 in Schwann cells but its activation elements have not yet been determined. Using chromatin immunoprecipitation analysis of the rat Pmp22 locus, we find a major peak of Egr2 binding within the large intron of the Pmp22 gene. Analysis of a 250 bp region within the largest intron showed that it is strongly activated by Egr2 expression in reporter assays. Moreover, this region contains conserved binding sites for not only Egr2 but also Sox10, which is also required for Schwann cell development. Our analysis shows that Sox10 is required for optimal activity of the intronic site as well as PMP22 expression. Finally, mouse transgenic analysis revealed tissue-specific expression of this intronic sequence in peripheral nerve. Overall, these data show that Egr2 and Sox10 activity are directly involved in mediating the developmental induction of Pmp22 expression
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