572 research outputs found

    Fatigue Behavior of Friction Stir Welded Joints of Pure Copper with Ultra-fine Grains

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    AbstractIn order to determine the long term durability of friction stir welded joints with ultra-fine grained microstructure, investigation of the mechanical response with specific emphasis on fatigue behaviour is critical. In this paper, fatigue behavior of friction stir welded joints of pure copper in low cycle; strain-controlled regime was investigated. Microstructural characterizations indicated the formation of recrystallized ultrafine-grained microstructure in the nugget zone (NZ) after friction stir welding. Fatigue properties were specified at a strain ratio of 0.1 with total strain amplitudes of 0.01, 0.1, and 0.2%. The results attained from the experiments demonstrated cyclic hardening effect at high strain amplitudes, while softening was observed in low strain amplitude of 0.01%. The hysteresis loops indicated the concavity along with the small portion of linear behavior after the reversal point. Localized deformation in the form of shear bands along with equiaxed cells and noticeable misorientation were observed on the fracture surface

    Equine Herpesvirus type 1 and 4 in Individually Reared Horses in Central and Western Turkey

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    The objective of the study was to investigate EHV type 1 and 4 infections serologically in individually reared horses in Turkey. Equine herpesvirus 1 (EHV1) and 4 comprise two distinct viruses of horses of the Alphaherpesvirinae subfamily. EHV1 is a major cause of abortion, respiratory and neurological disorders in horses. EHV4 is responsible for respiratory disease in foals. In this study, EHV1 and 4 infections were investigated serologically in individually reared horses in Turkey. A total of 188 unvaccinated horses in four provinces were sampled and tested using indirect ELISA. EHV1- specific antibodies were found to be in three out of four provinces as 3.7% (7/188) between 4.5–6.9%. Test results showed that EHV4 is more prevalent than EHV1, the proportion varied among 48.4% and 65.7% in four provinces, 107 out of 188 samples (56.9%) were found to be seropositive. This is the first serological investigation for EHV1 and EHV4 in Turkey

    Determination of heavy metal content in commercial marine fish hunted from southeast Aegean Sea (Turkey) and their potential risk for public health

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    In this study, heavy metals such as Al, Cr, Cu, Zn, Cd, Hg, Pb etc. content in liver, muscle and gill of three economical marine species [striped seabream (Lithognathus mormyrus Linneaus, 1758), two-band bream (Diplodus vulgaris Geoffroy Saint-Hilaire, 1817) and Common pandora (Pagellus erythrinus Linneaus, 1758)] obtained from 4 stations (Fethiye, Bodrum, Datça, Marmaris) in South Aegean coast were analyzed. After tissues were mineralized with wet-ashing, their heavy metal concentrations were measured with inductively coupled plasma mass spectrometry (ICP-MS). According to the findings, sediment samples had more heavy metals than water samples and none of heavy metal concentrations in the water samples exceeded national legal limits. Furthermore it was reported that the accumulation of heavy metal in liver and gill was the highest whereas in muscle the proportion was the lowest. Results showed that the mean concentration of the studied heavy metals in muscle tissues did not pose a risk in terms of public health in comparison with the international standards

    Brain Atrophy and Hypomyelination Associated with Iatrogenic Cushing’s Syndrome in an Infant

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    Prolonged use of topical corticosteroids, particularly in infants, albeit rare, may lead to Cushing's syndrome. Central nervous system abnormalities including brain atrophy and delayed myelination on cranial magnetic resonance imaging has been reported in patients with corticosteroid treatment. We herein report a 5-month-old female infant with brain atrophy and myelination delay that might be due to iatrogenic Cushing's syndrome caused by topical corticosteroid use

    Protocol study: Sexual and reproductive health knowledge, information-seeking behaviour and attitudes among Saudi women: A questionnaire survey of university students

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    Copyright © 2014 Farih et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background - Sexual and reproductive health (SRH), a basic right for women worldwide, is infrequently researched in countries in the Middle East and North Africa (MENA). No empirical studies of SRH among Saudi women exist. This protocol describes a study to explore the SRH knowledge, information-seeking behaviour and attitudes of Saudi female university students. Methods/Design - This study will administer a questionnaire survey to female students at 13 universities in Riyadh, Saudi Arabia. The questionnaire was developed following a literature search to identify relevant content, with psychometrically tested tools used when available. The content layout and the wording and order of the questions were designed to minimize the risk of bias. The questionnaire has been translated into Arabic and piloted in preparation for administration to the study sample. Ethical approval for the study has been granted (reference no. QMREC2012/54). After questionnaire administration, the data will be collated, analysed and reported anonymously. The findings will be published in compliance with reporting guidelines for survey research. Discussion - This study will be the first to provide fundamental information concerning Saudi females university students SRH knowledge and information needs.King Abdullah Scholarship Program, Saudi Arabi

    High-Transmission-Efficiency and Side-Viewing Micro OIDRS Probe for Fast and Minimally Invasive Tumor Margin Detection

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    The determination of a cancer free margin I organ is a difficult and time consuming process, with an unmet need for rapid determination of tumor margin at surgery. In this paper, we report the design, fabrication, and testing of a novel miniaturized optical sensor probe with “side-viewing” capability. Its unprecedented small size, unique “side-viewing” capability, and high optical transmission efficiency enable the agile maneuvering and efficient data collection even in the narrow cavities inside the human body. The sensor probe consists of four micromachined substrates with optical fibers for oblique light incidence and collection of spatially resolved diffuse reflectance from the contacted tissues. The optical sensor probe has been used to conduct the oblique incidence diffuse reflectance spectroscopy (OIDRS) on a human pancreatic specimen. Based on the measurement results, the margin of the malignant tumor has been successfully determined optically, which matches well with the histological results

    Prevalence and Associated Features of Anxiety Disorder Comorbidity in Bipolar Disorder: A Meta-Analysis and Meta-Regression Study

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    Objective: Bipolar disorder is highly comorbid with anxiety disorders, however current and lifetime comorbidity patterns of each anxiety disorder and their associated features are not well studied. Here, we aimed to conduct a meta-analysis and meta-regression study of current evidence.Method: We searched PubMed to access relevant articles published until September 2015, using the keywords “Bipolar disorder” or “Affective Psychosis” or “manic depressive” separately with “generalized anxiety,” “panic disorder,” “social phobia,” “obsessive compulsive,” and “anxiety.” Variables for associated features and prevalence of anxiety disorders were carefully extracted.Results: Lifetime any anxiety disorder comorbidity in BD was 40.5%; panic disorder (PD) 18.1%, generalized anxiety disorder (GAD) 13.3%, social anxiety disorder (SAD) 13.5% and obsessive compulsive disorder (OCD) 9.7%. Current any anxiety disorder comorbidity in BD is 38.2%; GAD is 15.2%, PD 13.3%, SAD 11.7%, and OCD 9.9%. When studies reporting data about comorbidities in BDI or BDII were analyzed separately, lifetime any anxiety disorder comorbidity in BDI and BDII were 38% and 34%, PD was 15% and 15%, GAD was 14% and 16.6%, SAD was 8% and 13%, OCD was 8% and 10%, respectively. Current any DSM anxiety disorder comorbidity in BDI or BDII were 31% and 37%, PD was 9% and 13%, GAD was 8% and 12%, SAD was 7% and 11%, and OCD was 8% and 7%, respectively. The percentage of manic patients and age of onset of BD tended to have a significant impact on anxiety disorders. Percentage of BD I patients significantly decreased the prevalence of panic disorder and social anxiety disorder. A higher rate of substance use disorder was associated with greater BD–SAD comorbidity. History of psychotic features significantly affected current PD and GAD.Conclusions: Anxiety disorder comorbidity is high in BD with somewhat lower rates in BDI vs BDII. Age of onset, substance use disorders, and percentage of patients in a manic episode or with psychotic features influences anxiety disorder comorbidity

    Bright ligand-activatable fluorescent protein for high-quality multicolor live-cell super-resolution microscopy

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    We introduce UnaG as a green-to-dark photoswitching fluorescent protein capable of high-quality super-resolution imaging with photon numbers equivalent to the brightest photoswitchable red protein. UnaG only fluoresces upon binding of a fluorogenic metabolite, bilirubin, enabling UV-free reversible photoswitching with easily controllable kinetics and low background under Epi illumination. The on- and off-switching rates are controlled by the concentration of the ligand and the excitation light intensity, respectively, where the dissolved oxygen also promotes the off-switching. The photo-oxidation reaction mechanism of bilirubin in UnaG suggests that the lack of ligand-protein covalent bond allows the oxidized ligand to detach from the protein, emptying the binding cavity for rebinding to a fresh ligand molecule. We demonstrate super-resolution single-molecule localization imaging of various subcellular structures genetically encoded with UnaG, which enables facile labeling and simultaneous multicolor imaging of live cells. UnaG has the promise of becoming a default protein for high-performance super-resolution imaging. Photoconvertible proteins occupy two color channels thereby limiting multicolour localisation microscopy applications. Here the authors present UnaG, a new green-to-dark photoswitching fluorescent protein for super-resolution imaging, whose activation is based on a noncovalent binding with bilirubin
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