32 research outputs found

    Twelve Channel Optical Fiber Connector Assembly: From Commercial Off the Shelf to Space Flight Use

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    The commercial off the shelf (COTS) twelve channel optical fiber MTP array connector and ribbon cable assembly is being validated for space flight use and the results of this study to date are presented here. The interconnection system implemented for the Parallel Fiber Optic Data Bus (PFODB) physical layer will include a 100/140 micron diameter optical fiber in the cable configuration among other enhancements. As part of this investigation, the COTS 62.5/125 microns optical fiber cable assembly has been characterized for space environment performance as a baseline for improving the performance of the 100/140 micron diameter ribbon cable for the Parallel FODB application. Presented here are the testing and results of random vibration and thermal environmental characterization of this commercial off the shelf (COTS) MTP twelve channel ribbon cable assembly. This paper is the first in a series of papers which will characterize and document the performance of Parallel FODB's physical layer from COTS to space flight worthy

    Response to the Novel Corona Virus (COVID-19) Pandemic Across Africa: Successes, Challenges, and Implications for the Future

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    Background: The COVID-19 pandemic has already claimed considerable lives. There are major concerns in Africa due to existing high prevalence rates for both infectious and non-infectious diseases and limited resources in terms of personnel, beds and equipment. Alongside this, concerns that lockdown and other measures will have on prevention and management of other infectious diseases and non-communicable diseases (NCDs). NCDs are an increasing issue with rising morbidity and mortality rates. The World Health Organization (WHO) warns that a lack of nets and treatment could result in up to 18 million additional cases of malaria and up to 30,000 additional deaths in sub-Saharan Africa. Objective: Document current prevalence and mortality rates from COVID-19 alongside economic and other measures to reduce its spread and impact across Africa. In addition, suggested ways forward among all key stakeholder groups. Our Approach: Contextualise the findings from a wide range of publications including internet-based publications coupled with input from senior-level personnel. Ongoing Activities: Prevalence and mortality rates are currently lower in Africa than among several Western countries and the USA. This could be due to a number of factors including early instigation of lockdown and border closures, the younger age of the population, lack of robust reporting systems and as yet unidentified genetic and other factors. Innovation is accelerating to address concerns with available equipment. There are ongoing steps to address the level of misinformation and its consequences including fines. There are also ongoing initiatives across Africa to start addressing the unintended consequences of COVID-19 activities including lockdown measures and their impact on NCDs including the likely rise in mental health disorders, exacerbated by increasing stigma associated with COVID-19. Strategies include extending prescription lengths, telemedicine and encouraging vaccination. However, these need to be accelerated to prevent increased morbidity and mortality. Conclusion: There are multiple activities across Africa to reduce the spread of COVID-19 and address misinformation, which can have catastrophic consequences, assisted by the WHO and others, which appear to be working in a number of countries. Research is ongoing to clarify the unintended consequences given ongoing concerns to guide future activities. Countries are learning from each other

    SmCL3, a Gastrodermal Cysteine Protease of the Human Blood Fluke Schistosoma mansoni

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    Parasitic infection caused by blood flukes of the genus Schistosoma is a major global health problem. More than 200 million people are infected. Identifying and characterizing the constituent enzymes of the parasite's biochemical pathways should reveal opportunities for developing new therapies (i.e., vaccines, drugs). Schistosomes feed on host blood, and a number of proteolytic enzymes (proteases) contribute to this process. We have identified and characterized a new protease, SmCL3 (for Schistosoma mansoni cathepsin L3), that is found within the gut tissue of the parasite. We have employed various biochemical and molecular biological methods and sequence similarity analyses to characterize SmCL3 and obtain insights into its possible functions in the parasite, as well as its evolutionary position among cathepsin L proteases in general. SmCL3 hydrolyzes major host blood proteins (serum albumin and hemoglobin) and is expressed in parasite life stages infecting the mammalian host. Enzyme substrate specificity detected by positional scanning-synthetic combinatorial library was confirmed by molecular modeling. A sequence analysis placed SmCL3 to the cluster of other cathepsins L in accordance with previous phylogenetic analyses

    Characterization of a novel testicular form of human hormone-sensitive lipase

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    Hormone-sensitive lipase (HSL) is an esterase and lipase, which are essential for spermatogenesis. Two HSL mRNAs are expressed in human testis. A long form is encoded by a testis-specific exon and nine exons common to testis and adipocyte HSL. Here we show that the short-form 3.3-kb mRNA possesses a unique 5' end that is transcribed from a novel testis-specific exon. The corresponding protein is similar to the 775-amino-acid-long adipocyte HSL. Immunohistochemistry experiments on human testis sections revealed that the long form is strictly expressed in haploid germ cells whereas the short form is expressed in interstitial and tubular somatic cells as well as premeiotic germ cells

    Hair Dye Substance Database (HDSD)

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    Fully 2D-curated database of 313 QSAR-ready hair dye substances available for download as Excel spreadsheet or SDF (structure-data file). Includes information such as substance name, structure, CASRNs, DTXSIDs, classes, color (if applicable), and computed properties. SDF can be opened using chemical drawing software such as ChemDraw Professional or MarvinView. Marvin (ChemAxon) can be downloaded at: https://chemaxon.com/products/marvin/download<div><br></div><div>New with Version 3: Better defined structures for substances with HDSD ID: 91, 99 and 110 (aromaticity issues resolved).</div><div><br></div><div>For details regarding database development, analysis, and potential applications, see https://dx.doi.org/10.1021/acssuschemeng.7b03795. <div><br></div><div> We are seeking to improve the HDSD. Please contact Tova N. Williams at [email protected] for suggestions.</div></div

    Toward the Rational Design of Sustainable Hair Dyes Using Cheminformatics Approaches: Step 1. Database Development and Analysis

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    Herein, we report on the initial step of the design process of new hair dyes with the desired properties. The first step is dedicated to the development of the largest, publicly available database of hair dye substances (containing temporary and semipermanent hair dyes as well as permanent hair dye precursors) used in commercial hair dye formulations. The database was utilized to perform a cheminformatics study assessing the computed physicochemical properties of the different hair dye substances, especially within each cluster of structurally similar dyes. The various substances could be differentiated based on their average molecular weight, hydrophobicity, topological polar surface area, and number of hydrogen bond acceptors, with some overlap also observed. In particular, we found that dyes such as C.I. Basic Orange 1 and 2 were clustered among the precursors, suggesting that their diffusion behavior is similar to that of permanent hair dye precursors. We anticipate taking advantage of this interesting knowledge in the second design phase of our investigation. As a step in that direction, we used QSAR models and noted that 65% of the substances were predicted to be mutagenic (22 with confidence thresholds >90%), whereas 79% were predicted to be skin sensitizers (37 with confidence thresholds >90%). We discuss the relevance of these preliminary calculations in view of literature-extracted experimental data

    Imposing compulsory Rugby Union on schoolchildren: an analysis of English state-funded secondary schools

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    Objective: to establish the extent to which Rugby Union was a compulsory physical education activity in state-funded secondary schools in England and to understand the views of Subject Leaders for Physical Education with respect to injury risk. Method: a cross-sectional research study using data obtained under the Freedom of Information Act (2000) from 288 state-funded secondary schools. Results: Rugby Union was delivered in 81% (n = 234 of 288) of state-funded secondary school physical education curricula, including 83% (n = 229 of 275) of state-funded secondary school boys’ and 54% (n = 151 of 282) of girls’ physical education curricular. Rugby Union was compulsory in 91% (n = 208 of 229) of state-funded secondary schools that delivered it as part of the boys’ physical education curriculum and 54% (n = 82 of 151) of state-funded secondary schools that delivered contact Rugby Union as part of the girls’ physical education curriculum. Subject Leaders for Physical Education also perceived Rugby Union to have the highest risk of harm of the activities they delivered in their school physical education curriculum. Conclusion: Notwithstanding discussions of appropriate measures (i.e., mandatory concussion training, Rugby Union specific qualifications and CPD) to reduce injury risk, it is recommended that Rugby Union should not be a compulsory activity given that it has a perceived high risk of injury and is an unnecessary risk for children in physical education
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