2,228 research outputs found

    Global transcriptomic response of Leptospira interrogans serovar Copenhageni upon exposure to serum

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    <p>Abstract</p> <p>Background</p> <p>Leptospirosis is a zoonosis of worldwide distribution caused by infection with pathogenic serovars of <it>Leptospira </it>spp. The most common species, <it>L. interrogans</it>, can survive in the environment for lengthy periods of time in between infection of mammalian hosts. Transmission of pathogenic <it>Leptospira </it>to humans mostly occurs through abraded skin or mucosal surfaces after direct or indirect contact with infected animals or contaminated soil or water. The spirochete then spreads hematogenously, resulting in multi-organ failure and death in severe cases. Previous DNA microarray studies have identified differentially expressed genes required for adaptation to temperature and osmolarity conditions inside the host compared to those of the environment.</p> <p>Results</p> <p>In order to identify genes involved in survival in the early spirochetemic phase of infection, we performed a transcriptional analysis of <it>L. interrogans </it>serovar Copenhageni upon exposure to serum in comparison with EMJH medium. One hundred and sixty-eight genes were found to be differentially expressed, of which 55 were up-regulated and 113 were down-regulated. Genes of known or predicted function accounted for 54.5 and 45.1% of up- and down-regulated genes, respectively. Most of the differentially expressed genes were predicted to be involved in transcriptional regulation, translational process, two-component signal transduction systems, cell or membrane biogenesis, and metabolic pathways.</p> <p>Conclusions</p> <p>Our study showed global transcriptional changes of pathogenic <it>Leptospira </it>upon exposure to serum, representing a specific host environmental cue present in the bloodstream. The presence of serum led to a distinct pattern of gene expression in comparison to those of previous single-stimulus microarray studies on the effect of temperature and osmolarity upshift. The results provide insights into the pathogenesis of leptospirosis during the early bacteremic phase of infection.</p

    Cloud2FEM: A finite element mesh generator based on point clouds of existing/historical structures

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    Nowadays, the common output of surveying activities on existing/historical structures consists of dense point clouds. However, the direct and automatic exploitation of point clouds for structural purposes, i.e. to generate finite element models, is still very limited. In this framework, the Cloud2FEM software supplies an automatic finite element mesh generator based on point clouds of existing/historical structures. Cloud2FEM is based on open-source Python libraries with graphical interface. The point cloud is initially sliced along with the vertical direction. Then, closed polygons are recognized on each slice and stacked vertically thanks to the use of voxels. The voxelized volume is exported into 3D solid hexahedron-based finite element meshes. Suitable graphical tools are developed to help the user adjusting local potential criticalities in the slices, also when partial information is missing in the points cloud. An illustrative example is given to highlight the Cloud2FEM potentialities

    Community Priority Index: utility, applicability and validation for priority setting in community-based participatory research

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    Background. Providing practitioners with an intuitive measure for priority setting that can be combined with diverse data collection methods is a necessary step to foster accountability of the decision-making process in community settings. Yet, there is a lack of easy-to-use, but methodologically robust measures, that can be feasibly implemented for reliable decision-making in community settings. To address this important gap in community based participatory research (CBPR), the purpose of this study was to demonstrate the utility, applicability, and validation of a community priority index in a community-based participatory research setting. Design and Methods. Mixed-method study that combined focus groups findings, nominal group technique with six key informants, and the generation of a Community Priority Index (CPI) that integrated community importance, changeability, and target populations. Bootstrapping and simulation were performed for validation. Results. For pregnant mothers, the top three highly important and highly changeable priorities were: stress (CPI=0.85; 95%CI: 0.70, 1.00), lack of affection (CPI=0.87; 95%CI: 0.69, 1.00), and nutritional issues (CPI=0.78; 95%CI: 0.48, 1.00). For non-pregnant women, top priorities were: low health literacy (CPI=0.87; 95%CI: 0.69, 1.00), low educational attainment (CPI=0.78; 95%CI: 0.48, 1.00), and lack of self-esteem (CPI=0.72; 95%CI: 0.44, 1.00). For children and adolescents, the top three priorities were: obesity (CPI=0.88; 95%CI: 0.69, 1.00), low self-esteem (CPI=0.81; 95%CI: 0.69, 0.94), and negative attitudes toward education (CPI=0.75; 95%CI: 0.50, 0.94). Conclusions. This study demonstrates the applicability of the CPI as a simple and intuitive measure for priority setting in CBPR

    The market efficiency in the stock markets

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    We study the temporal evolution of the market efficiency in the stock markets using the complexity, entropy density, standard deviation, autocorrelation function, and probability distribution of the log return for Standard and Poor's 500 (S&P 500), Nikkei stock average index, and Korean composition stock price index (KOSPI). Based on the microscopic spin model, we also find that these statistical quantities in stock markets depend on the market efficiency.Comment: 8 pages, 5 figure

    How cold is Dark Matter? Constraints from Milky Way Satellites

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    We test the luminosity function of Milky Way satellites as a constraint for the nature of Dark Matter particles. We perform dissipationless high-resolution N-body simulations of the evolution of Galaxy-sized halo in the standard Cold Dark Matter (CDM) model and in four Warm Dark Matter (WDM) scenarios, with a different choice for the WDM particle mass (m_w). We then combine the results of the numerical simulations with semi-analytic models for galaxy formation, to infer the properties of the satellite population. Quite surprisingly we find that even WDM models with relatively low m_w values (2-5 keV) are able to reproduce the observed abundance of ultra faint (Mv<-9) dwarf galaxies, as well as the observed relation between Luminosity and mass within 300 pc. Our results suggest a lower limit of 1 keV for thermal warm dark matter, in broad agreement with previous results from other astrophysical observations like Lyman-alpha forest and gravitational lensing.Comment: 6 pages, 5 figures. Introduction improved, references added. Accepted for publication on MNRAS Letter

    Vesicostomy as a Protector of Upper Urinary Tract in Long-Term Follow-Up

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    Introduction: The aim of this study was to analyze the results of vesicostomy in children as a protector of the upper urinary tract and assess the adjustments taken by the caregivers. Materials and Methods: Twenty-one children who had undergone vesicostomy with the Blocksom technique were evaluated. Their mean age was 3.7 years (range, < 1 to 10 years). The evaluation consisted of kidney function tests, cystography, and analysis of complications. Twenty parents or caregivers were interviewed about their attitudes towards vesicostomy and its outcomes. Results: The main causes of the vesical dysfunction were posterior urethral valve in 7 (33.3%) and myelomeningocele in 5 patients (23.8%). Ten children (58.8%) showed improvement and 7 (41,2%) showed cure. Hydronephrosis observed in 17 children was alleviated or cured following the procedure. Kidney function, tested by creatinine clearance calculation, remained stable or improved in 20 patients (95.2%). Episodes of urinary tract infection and 1 (71.4%), vesicoureteral reflux lowered in 8 of 21 (38.1%) and 10 of 14 patients respectively. Subjective evaluation of 20 cases showed that 18 children (90.0%) remained dry during the day and 14 caregivers/parents (70.0%) felt they had acquired the skills necessary to handle a patient with vesicostomy. The mean global rate of satisfaction of the results of the surgery ranging from 0 (worst result) to 10 (best result) was 8.7. Conclusion: Vesicostomy is a simple surgery that protects the upper urinary tract, decreases hydronephrosis, and improves kidney function. There was adequate adjustment to vesicostomy and a positive global evaluation as reported by the parents and caregivers.629610

    Fully Dynamic Numerical Simulation of the Hammer Peening Fatigue Life Improvement Technique

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    AbstractThis paper presents the results of the development process for a Finite Element Analysis of the Hammer Peening Fatigue Life Improvement Technique. The Fatigue Life of welded structures is still in need for improvement. The sheer number of Fatigue Live Improvement Techniques parameters leads to the need of simulating and predicting their results. For this study, two different materials were used, an Austenitic Stainless Steel and a Duplex Stainless Steel. Non-load carrying cruciform weld joints were produced and fatigue tested, with and without the Hammer Peening treatment. Finally a FEA code (ABAQUS®) was used to simulate the Hammer Peening technique. A fully dynamic model was used, combined with the Chaboche Kinematic-hardening material model and different Hammering parameter experimentally determined. Alongside the residual stresses introduced by the Hammer Peening Technique, the predicted Fatigue Life using the FEA model were compared with the experimental results, showing a very good agreement between them. Also the effect of several parameters, like the hammering impact load, the hammer positioning or the number of hammering passages, were analysed as a way to validate the FEA model. The most important result was of course the Fatigue Strength Gain factor, for the Hammer Peening Technique, that in both cases was found to be superior to 1.3

    Implementing mentor mothers in family practice to support abused mothers: Study protocol

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    Contains fulltext : 97988.pdf (postprint version ) (Open Access)ABSTRACT: BACKGROUND: Intimate partner violence is highly prevalent and mostly affects women with negative consequences for their physical and mental health. Children often witness the violence which has negative consequences for their well-being too. Care offered by family physicians is often rejected because abused women experience a too high threshold. Mentor mother support, a low threshold intervention for abused mothers in family practice, proved to be feasible and effective in Rotterdam, the Netherlands. The primary aim of this study is to investigate which factors facilitate or hinder the implementation of mentor mother support in family practice. Besides we evaluate the effect of mentor mother support in a different region. METHODS/DESIGN: An observational study with pre- and posttests will be performed. Mothers with home living children or pregnant women who are victims of intimate partner violence will be offered mentor mother support by the participating family physicians. The implementation process evaluation consists of focus groups, interviews and questionnaires. In the effect evaluation intimate partner violence, the general health of the abused mother, the mother-child relationship, social support, and acceptance of professional help will be measured twice (t = 0 and t = 6 months) by questionnaires, reporting forms, medical records and interviews with the abused mothers. Qualitative coding will be used to analyze the data from the reporting forms, medical records, focus groups, interviews, and questionnaires. Quantitative data will be analyzed with descriptive statistics, chi square test and t-test matched pairs. DISCUSSION: While other intervention studies only evaluate the feasibility and effectiveness of the intervention, our primary aim is to evaluate the implementation process and thereby investigate which factors facilitate or hinder implementation of mentor mother support in family practice.6 p

    Ovine multiparity is associated with diminished vaginal muscularis, increased elastic fibres and vaginal wall weakness: implication for pelvic organ prolapse

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    This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/Pelvic Organ Prolapse (POP) is a major clinical burden affecting 25% of women, with vaginal delivery a major contributing factor. We hypothesised that increasing parity weakens the vagina by altering the extracellular matrix proteins and smooth muscle thereby leading to POP vulnerability. We used a modified POP-quantification (POP-Q) system and a novel pressure sensor to measure vaginal wall weakness in nulliparous, primiparous and multiparous ewes. These measurements were correlated with histological, biochemical and biomechanical properties of the ovine vagina. Primiparous and multiparous ewes had greater displacement of vaginal tissue compared to nulliparous at points Aa, Ap and Ba and lower pressure sensor measurements at points equivalent to Ap and Ba. Vaginal wall muscularis of multiparous ewes was thinner than nulliparous and had greater elastic fibre content. Collagen content was lower in primiparous than nulliparous ewes, but collagen organisation did not differ. Biomechanically, multiparous vaginal tissue was weaker and less stiff than nulliparous. Parity had a significant impact on the structure and function of the ovine vaginal wall, as the multiparous vaginal wall was weaker and had a thinner muscularis than nulliparous ewes. This correlated with “POP-Q” and pressure sensor measurements showing greater tissue laxity in multiparous compared to nulliparous ewes

    Exploring the Life Course Perspective in Maternal and Child Health through Community-Based Participatory Focus Groups: Social Risks Assessment

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    Little is known about the patterns of risk factors experienced by communities of color and how diverse community contexts shape the health trajectory of women from the early childhood period to the time of their pregnancies. Thus, we conducted a focus group study to identify social risks over the life course that contribute to maternal and child health from the perspective of community members residing in low income urban areas. Ten community-based participatory focus groups were conducted with residents from selected communities in Tampa, Florida, from September to November 2013. We used the life course perspective to illuminate and explain the experiences reported by the interviewees. A total of 78 residents participated in the focus groups. Children and adolescents’ health risks were childhood obesity, lack of physical activity, and low self-esteem. Women’s health risks were low self-esteem, low educational level, low health literacy, inadequate parenting skills, and financial problems. Risks during pregnancy included stress, low self-esteem, inadequate eating patterns, lack of physical activity, healthcare issues, lack of social support, and lack of father involvement during pregnancy. Multiple risk factors contribute to maternal and child health in low income communities in Tampa Bay. The intersection of risk factors in different life periods suggest possible pathways, cumulative, and latent effects, which must be considered in future longitudinal studies and when developing effective maternal and child health programs and policies
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