243 research outputs found

    The future impact of climate and land-use changes on Anatolian ground squirrels under different scenarios

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    Climate and land-use changes are among the most important drivers of biodiversity loss and, moreover, their impacts on biodiversity are expected to increase further in the 21st century. In this study, the future impact of climate and land-use changes on Anatolian ground squirrels (Spermophilus xanthoprymnus) was assessed. Accordingly, a hierarchical approach with two steps was used. First, ecological niche modelling was used to assess the impact of climate change in areas accessible to Anatolian ground squirrels through dispersal (i.e. the impact of climate change). Second, based on the habitat preferences of ground squirrels, land-use data were used to assess the impact of land-use change in suitable bioclimatic areas for Anatolian ground squirrels under present and future conditions (i.e. the combined impact of both changes). Also, priority areas for the conservation of Anatolian ground squirrels were identified based on in-situ climate change refugia. This study represents a first attempt to combine niche modelling and land-use data for a species in Anatolia, one of the most vulnerable regions to the drivers of biodiversity loss, because it is the region where three of biodiversity hotspots meet, and interact. Habitat suitability (i.e. suitable habitats across suitable bioclimatic areas) was projected to decline by 19-69% in the future (depending on the scenario), mainly due to the loss of suitable bioclimatic areas (47-77%, depending on the scenario) at lower elevations and in the western part of the central Anatolia and in the eastern Anatolia, suggesting that Anatolian ground squirrels will contract their range in the future, mainly due to climate change. Thus, in-situ climate change refugia were projected mainly in the eastern and southeastern parts of the central Anatolia, suggesting these regions as priority areas for the conservation of Anatolian ground squirrels

    Nondestructive Evaluation of Additively Manufactured Metallic Components

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    Nondestructive evaluation (NDE) methods are successfully used for detection of surface and internal flaws, and also for characterization of materials. Additive manufacturing (AM) of metallic components is rather complicated due to many process variables affecting the performance and quality of the final product. Qualification, verification, and industry adoption of AM parts is dependent upon the capability of NDE. This paper presents the initial results of the on-going studies about NDE of additively manufactured metallic parts, performed at METU

    Effects of heat input on metallurgical behavior in HAZ of multi-pass and multi-layer welded IN-939 superalloy

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    The hot components of a gas turbine are susceptible to damage in the high-temperature environment of turbine engine operation. Given that these components are relatively costly to manufacture, they are often repaired than replaced when damaged. Fusion welding is an economical method for repairing the damaged components of a gas turbine. This research examines the roles of heat input, pass number and layer number on the intergranular liquation cracking of the Inconel-939 (IN-939) precipitate nickel base superalloy during tungsten arc welding. Several specimens were welded with IN-625 filler alloy under argon gas by following the Taguchi method and an L8 array. These specimens were then characterized via metallographic investigations and hardness measurements. Results show that, during welding, the IN-939 heat-affected zone (HAZ) is acutely prone to cracks that propagate along the grain boundaries. Moreover, layer number, heat input and pass number significantly influence the microstructure and liquation cracking of HAZs with impact percentages of 72.37%, 22.17% and 4.84%, respectively

    The Value of Serum Biomarkers (Bc1, Bc2, Bc3) in the Diagnosis of Early Breast Cancer

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    Background: Surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF) is an approach to biomarker discovery that combines chromatography and mass spectrometry. We aimed to consider the efficacy of Bc1, Bc2, and Bc3 serum biomarkers on early detection of breast cancer (BC) in this study

    Validity and reliability of the assessment tool for Asthma (ATA) questionnaire: the ATA study

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    OBJECTIVES: A multicenter trial was designed to validate the “Assessment Tools for Asthma (ATA)” questionnaire, a newly developed questionnaire, which evaluates both asthma control and risk factors associated with asthma control with a single instrument. MATERIALS AND METHODS: This cross-sectional study involved 810 cases from 14 clinics in 9 Turkish cities. The ATA questionnaire and Asthma Control Test (ACT) were administered. The Visual Analog Scale (VAS) was used to evaluate the control status of 100 randomized cases. ATA is an eight-item physician-administered questionnaire. It comprises the following two sections-ATA1, assesses symptomatic control criteria, and the remaining section, queries the flre-up of asthma, control of comorbidities, treatment adherence, and inhaler technique. RESULTS: The mean scores for ATA1, ATA total, VAS, and ACT were 24.7±14.8, 53.8±19, 7.1±3, and 18.8±5.5, respectively. According to the ATA questionnaire, among all patients, 34.3% had controlled, 18.8% had partly controlled, and 46.9% had uncontrolled asthma. Furthermore, 16.6% patients had flre-ups between visits, 96.4% patients had uncontrolled comorbidity, 17% patients had irregular asthma treatment, and only 8.4% patients used the incorrect inhaler technique. The ATA questionnaire showed internal consistency (Cronbach’s alpha coeffiient=0.683). ACT, ATA1, and two specialists’ evaluations using VAS correlated strongly with the ATA total scores (Spearman correlation coeffiient (r) values: 0.776, 0.783, and 0.909, respectively; p-values: p<0.001, p<0.001, and p<0.001, respectively). According to Receiver Operating Characteristic analysis, the cut-off value of ATA was 50 (sensitivity=84.4%, specifiity=82.40%). CONCLUSION: The validated ATA questionnaire may be a practical tool for physicians in asthma management
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