5,646 research outputs found

    A new coordinate transformation for turbulent boundary layer flows

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    The transformation permits a uniform mesh to be used in the computational coordinate which extends across the layer. This coordinate transformation uses the local value of the skin friction coefficient to scale the thickness of the wall layer region, and the local maximum value of turbulent viscosity to scale the boundary-layer thickness. Results are presented for two dimensional boundary layers in both positive and negative pressure gradients and comparisons are made with experimental data and conventional variable-grid results for low speed turbulent boundary-layers. The cases chosen illustrate the capability of this new transformation to capture the boundary layer growth over the full extent of laminar, transitional, and turbulent flow with no grid adjustment as well as its ability to consistently enlarge the wall layer region for accurate shear stress representation. Results of mesh refinement studies using the new coordinate transformation are presented

    Identifying infection in chronic wounds in a community setting: a systematic review of diagnostic test accuracy studies

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    To determine the diagnostic accuracy of different methods currently available to identify infection in chronic wounds applicable to adult patients in a community setting. Systematic review of diagnostic test accuracy studies. Two authors independently completed screening, data extraction and quality and bias assessments (QUADAS2). Eligible studies compared a method (index test) for detecting infection (diagnosis of interest) with microscopy and culture of either deep tissue biopsy or wound swab (reference test) in adult patients with wounds of >4 weeks duration (participants). The results were synthesized narratively. We systematically searched CINAHL, Embase and Medline from 2011 to April 2022. Four studies were included, all recruiting from secondary care wound clinics. Two studies assessed the diagnostic accuracy of Moleculight i:X, a bacterial fluorescence imaging device against deep tissue biopsy culture. One study assessed the diagnostic accuracy of the elevation of various enzymes detected in wound fluid against wound swab microscopy of culture. One study assessed the diagnostic accuracy of bacterial protease activity against wound swab microscopy and culture. Sensitivities of these methods ranged from 50 to 75% and specificities from 47 to 100%. Only a small number of studies were included in this systematic review due to our strict inclusion criteria. We have not identified any methods for diagnosing infection in chronic wounds with either a sufficient quality of evidence to recommend their use in community settings at present. Further research is needed to develop and evaluate appropriate diagnostics for this purpose. This study highlights the paucity of research into wound diagnostics in a community setting and should prompt further research in this area. Accurate diagnostic tests have the potential to improve community-based wound care by optimizing antibiotic use and potentially improving healing time. PRISMA-DTA checklist. The PPI group for the NIHR Community Healthcare MIC were supportive of this topic of work

    Als3 is a Candida albicans invasin that binds to cadherins and induces endocytosis by host cells.

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    Candida albicans is the most common cause of hematogenously disseminated and oropharyngeal candidiasis. Both of these diseases are characterized by fungal invasion of host cells. Previously, we have found that C. albicans hyphae invade endothelial cells and oral epithelial cells in vitro by inducing their own endocytosis. Therefore, we set out to identify the fungal surface protein and host cell receptors that mediate this process. We found that the C. albicans Als3 is required for the organism to be endocytosed by human umbilical vein endothelial cells and two different human oral epithelial lines. Affinity purification experiments with wild-type and an als3delta/als3delta mutant strain of C. albicans demonstrated that Als3 was required for C. albicans to bind to multiple host cell surface proteins, including N-cadherin on endothelial cells and E-cadherin on oral epithelial cells. Furthermore, latex beads coated with the recombinant N-terminal portion of Als3 were endocytosed by Chinese hamster ovary cells expressing human N-cadherin or E-cadherin, whereas control beads coated with bovine serum albumin were not. Molecular modeling of the interactions of the N-terminal region of Als3 with the ectodomains of N-cadherin and E-cadherin indicated that the binding parameters of Als3 to either cadherin are similar to those of cadherin-cadherin binding. Therefore, Als3 is a fungal invasin that mimics host cell cadherins and induces endocytosis by binding to N-cadherin on endothelial cells and E-cadherin on oral epithelial cells. These results uncover the first known fungal invasin and provide evidence that C. albicans Als3 is a molecular mimic of human cadherins

    Keck/LRIS Spectroscopic Confirmation of Coma Cluster Dwarf Galaxy Membership Assignments

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    Keck/LRIS multi-object spectroscopy has been carried out on 140 of some of the lowest and highest surface brightness faint (19 < R < 22) dwarf galaxy candidates in the core region of the Coma Cluster. These spectra are used to measure redshifts and establish membership for these faint dwarf populations. The primary goal of the low surface brightness sample is to test our ability to use morphological and surface brightness criteria to distinguish between Coma Cluster members and background galaxies using high resolution HST/ACS images. Candidates were rated as expected members, uncertain, or expected background. From 93 spectra, 51 dwarf galaxy members and 20 background galaxies are identified. Our morphological membership estimation success rate is ~100% for objects expected to be members and better than ~90% for galaxies expected to be in the background. We confirm that low surface brightness is a very good indicator of cluster membership. High surface brightness galaxies are almost always background with confusion arising only from the cases of the rare compact elliptical galaxies. The more problematic cases occur at intermediate surface brightness. Many of these galaxies are given uncertain membership ratings, and these were found to be members about half of the time. Including color information will improve membership determination but will fail for some of the same objects that are already mis-identified when using only surface brightness and morphology criteria. Compact elliptical galaxies with B-V colors ~0.2 magnitudes redward of the red sequence in particular require spectroscopic follow-up. In a sample of 47 high surface brightness, UCD candidates, 19 objects have redshifts which place them in the Coma Cluster. Redshift measurements are presented and the use of indirect means for establishing cluster membership is discussed.Comment: Accepted for publication in ApJ, 25 pages, 15 figure

    An Internet-Based Weight Loss Intervention Initiated by a Newspaper

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    Background: An estimated two-thirds of North Carolina residents are overweight or obese. Mass media, such as newspapers and the Internet, can be used to broadly convey health messages for weight loss. Context: Newspapers have traditionally been a primary source of health information for the general public. They may be uniquely suited to initiate and manage a community-based weight loss program by quickly reaching a broad readership. Methods: Participants in the 2005 Lose to Win weight loss challenge visited the Herald-Sun Web site and anonymously entered a nickname and identification number and reported their weight each week. Participants had access to weekly articles on diet and physical activity and 4 free educational seminars. Consequences: Of the 154 participants who self-reported weight at baseline and during the last week of the challenge, the mean weight lost was 5.9 lb. Interpretation: Results suggest that this challenge fostered health awareness and promoted weight loss in the community. Future interventions of this type should use strategies to increase participation and retention, improve the accuracy of reported weight, and evaluate long-term success of the program. This type of intervention may be a useful first step to reach residents who are interested in losing weight

    Book review of 'the people make the place: dynamic linkages between individuals and organizations edited by D. Brent Smith'

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    The People Make the Place is a festschrift celebrating the work of industrial/organizational psychologist Benjamin Schneider. It contains 11 specially written chapters each addressing a different element of Schneider’s work. The twelfth chapter, written by the honored scholar, summarizes the contributions and uses the opportunity to clarify many of the ideas surrounding attraction-selection-attrition (ASA) theory

    Carcinomas of Distal Fallopian Tube and Their Association with Tubal Intraepithelial Carcinoma: Do They Share a Common “Precursor” Lesion? Loss of Heterozygosity and Immunohistochemical Analysis Using PAX 2, WT-1, and P53 Markers

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    As the role of distal fallopian tube as organ of serous carcinogenesis is emerging, additional literature on the role of tubal intraepithelial carcinoma (TIC) as a precursor lesion in a subset of primary peritoneal serous carcinomas (PPSC is emerging as well. TIC although fallopian tube in origin can be genetically related to ovarian/peritoneal carcinomas. The role of PAX2 in primary fallopian tube carcinomas (PFTC)/PPSC is yet to be defined. The aim of our study was to understand if the biologic properties of tumors arising in the distal fallopian tube that remain as PFTC are different when they seed on to the peritoneal surface (PPSC). A panel of 6 polymorphic microsatellite markers corresponding to p53, PAX2, and WT1 tumor suppressor genes were studied. Invasive carcinomas as well as TIC arising in the distal fallopian tube when remain as PFTC appears to exhibit different LOH patterns in comparison to PPSC. PAX 2 LOH patterns might represent a “hidden PAX 2 signature” analogous to p53 signatures. PAX 2 might be an emerging marker for detection of early serous carcinomas particularly in BRCA + women
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