26 research outputs found
Mild-to-Moderate Kidney Dysfunction and Cardiovascular Disease: Observational and Mendelian Randomization Analyses
BACKGROUND: End-stage renal disease is associated with a high risk of cardiovascular events. It is unknown, however, whether mild-to-moderate kidney dysfunction is causally related to coronary heart disease (CHD) and stroke. METHODS: Observational analyses were conducted using individual-level data from 4 population data sources (Emerging Risk Factors Collaboration, EPIC-CVD [European Prospective Investigation into Cancer and Nutrition-Cardiovascular Disease Study], Million Veteran Program, and UK Biobank), comprising 648 135 participants with no history of cardiovascular disease or diabetes at baseline, yielding 42 858 and 15 693 incident CHD and stroke events, respectively, during 6.8 million personyears of follow-up. Using a genetic risk score of 218 variants for estimated glomerular filtration rate (eGFR), we conducted Mendelian randomization analyses involving 413 718 participants (25917 CHD and 8622 strokes) in EPIC-CVD, Million Veteran Program, and UK Biobank. RESULTS: There were U-shaped observational associations of creatinine-based eGFR with CHD and stroke, with higher risk in participants with eG FR values 105 mL.min(-1).1.73 m(-2), compared with those with eG FR between 60 and 105 mL.min(-1).1.73 m(-2). Mendelian randomization analyses for CHD showed an association among participants with eGFR 105 mL.min(-1).1.73 m(-2). Results were not materially different after adjustment for factors associated with the eGFR genetic risk score, such as lipoprotein(a), triglycerides, hemoglobin Alc, and blood pressure. Mendelian randomization results for stroke were nonsignificant but broadly similar to those for CHD. CONCLUSIONS: In people without manifest cardiovascular disease or diabetes, mild-to-moderate kidney dysfunction is causally related to risk of CHD, highlighting the potential value of preventive approaches that preserve and modulate kidney function
Hydrogen production from some agricultural residues by catalytic subcritical and supercritical water gasification
The subcritical and supercritical water gasification of residue of some agricultural biomass samples (cotton and tobacco stalks) was investigated in a batch reactor at temperature range of 300-600 °C and experiments were performed by addition of 10 wt.% of different natural mineral catalysts (Trona, Dolomite and Borax). The yield and composition of gaseous, aqueous products and residue were identified by different analytical techniques. Gaseous products consisted mainly of permanent gases such as hydrogen, carbon dioxide, methane, carbon monoxide and C 2-C 4 compounds. Aqueous products consisted mainly of carboxylic acids (hydroxyacetic acid, formic acid and acetic acid), furfurals, phenols (phenol and cresols), aldehydes (formaldehyde and acetaldehyde). The effectiveness of three different natural mineral catalysts in SCWG can be classified as being Trona [Na 3(CO 3)(HCO 3)·2H 2O] > Borax [Na 2B 4O 7·10H 2O] > Dolomite [CaMg(CO 3) 2]. The results showed that the addition of Trona as catalysts at reaction temperature of 600 °C, hydrogen yields of tobacco and cotton stalks were increased by 42.9% and 39.9%, respectively.© 2012 Published by Elsevier B.V.2008BIL017 106T748 National Council for Scientific ResearchWe gratefully acknowledge the financial support provided by The Scientific and Technological Research Council of Turkey (TÜBİTAK) (Project No: 106T748) and Ege University-EBILTEM (Project No: 2008BIL017). Thanks go to Mr. G. Serin for the feed preparation procedure and the mechanical work during the experiments. -
Comparative study of the thermoluminescence properties of natural metamorphic quartz belonging to Turkey and Spain
The aim of this study is to investigate the sensitization of the thermoluminescence (TL) peak of metamorphic quartzes from Adiyaman in Turkey (TMQ) and from Madrid in Spain (SMQ). Quartz samples of two different origins were ß-irradiated between ~6.689. Gy and 4816. Gy at room temperature. X-ray diffraction analysis has indicated that both TMQ and SMQ have the same crystal structure. Chemical analyses of both TMQ and SMQ were performed using the XRF technique. The preheat processes were carried out at 125. °C for 10. s in the TL measurement. TMQ and SMQ samples have different TL properties in two ways. First TMQ has four first order TL glow peaks while SMQ has five first order TL peaks and secondly, the observed dose sensitivity of TMQ samples is higher than the SMQ samples. © 2013 Elsevier Ltd.105Y349This study was carried out at the Cukurova University, Adiyaman University. The authors are grateful to TUBITAK (Turkish Scienti?c and Technology Research Council) for its ?nancial support under the contract number 105Y349 to purchase RISØ TL/OSL DA-20 equipment
Study of thermoluminescence response of purple to violet amethyst quartz from Balikesir, Turkey
In thermoluminescence (TL) dosimetry, the phosphor amethyst quartz as a thermoluminescent, appears to be one of the materials arousing the highest interest. In this study the dosimetric characteristics of natural amethyst quartz crystals collected from Balikesir-Dursunbey (Turkey) were investigated for the purpose of determination of the general properties that phosphors should have in order to be useful for thermoluminescence dosimetry. The natural thermoluminescence was drained by annealing the powder samples at 450 °C for 1.5 h. The effects of high temperature annealing, dose response curves, glow curves after a postirradiation annealing, reusability of the samples and storage of trapped electrons in dark at room temperature were clarified through irradiating the samples with the desired exposures by 90Sr/90Y beta particles. Isothermal annealing before and after irradiation was found to have a definite effect upon the TL glow curve of amethyst crystal powder. The same sample varied in sensitivity depending upon its previous thermal and radiation history. The peak heights of the glow peaks were examined with respect to dose response at dose levels between 1 Gy and 5 kGy. The intermediate temperature (IT) and high temperature (HT) peaks of 230 °C and 300 °C, respectively, exhibit dose-response curves as superlinear when dose is on the logarithmic scale except the dose response of 300 °C peak for the dose values of 1 < D < 20 Gy in which linear dose response was acquired. At the end of the storage time between exposure and readout which was about one month at room temperature, the emitted light reduction was 14% comparing to the initial state. Repeating the measurements of the same sample, exposed with 0.1, 0.5, 0.8 and 1 kGy beta exposures, resulted in between 4% and 11% increase in the TL sensitivity of the material. © 2015 Elsevier B.V. All rights reserved.105Y349This study was carried out at Çukurova University (CU), Department of Physics. We are grateful to TUBITAK ( Turkish Scientific and Technology Research Council ) for its financial support under the Contract No. 105Y349 to purchase RISO TL/OSL DA-20 equipment. We would like to acknowledge the Çukurova University Rectorate , Scientific Research Unit for its providing the financial support for this research as a PhD study under the Contract No. FEF2006D11 . [48] http://www.thermoscientific.com/en/product/tld-100-thermoluminescent-dosimetry-material.html . [49] http://www.thermoscientific.com/en/product/high-sensitivity-lif-mg-cu-p-thermoluminescent-dosimetry-materials-1.html . [50] http://www.thermoscientific.com/en/product/tld-200-thermoluminescent-dosimetry-material.html . [51] http://www.landauer.com/Industry/Products/Dosimeters/nanoDot_OSLD.aspx
Numerical solutions and error estimations for the space fractional diffusion equation with variable coefficients via Fibonacci collocation method
Scalable manufacturing of fibrous nanocomposites for multifunctional liquid sensing
Cellulose-based paper electronics is an attractive technology to meet the growing demands for naturally abundant, biocompatible, biodegradable, flexible, inexpensive, lightweight and highly miniaturizable sensory materials. The price reduction of industrial carbon nanotube (CNT) grades offers opportunities to manufacture electrically conductive papers whose resistivity is responsive to environmental stimuli, such as the presence of water or organic solvents. Here, a highly sensitive paper nanocomposite is developed by integrating CNTs into a hierarchical network of pulp fibers and nanofibrillated cellulose. The aqueous-phase dynamic web forming process enables the scalable production of sensory paper nanocomposites with minimal nanoparticle loss due to the tailored interfacial bonding between CNT and cellulose components. The resulting materials are applied as multifunctional liquid sensors, such as leak detection and wave monitoring. The sensitivity to liquid water spans an outstanding four orders of magnitude even after 30 cycles and 6-month natural aging, due to the hydroexpansion of the hierarchical cellulose network, which alters the intertube distance between neighboring CNTs. The re-organization of percolated CNTs modifies the electron transport in wet areas of the sheet, which can be predicted by an equivalent circuit of resistors for the rapid detection and quantification of various liquids over large surfaces
Shifted Legendre method with residual error estimation for delay linear Fredholm integro-differential equations
Nivolumab for relapsed or refractory Hodgkin lymphoma: Real-life experience
Background: Reed-Sternberg cells of classical Hodgkin's lymphoma (cHL) are characterized by genetic alterations at the 9p24.1 locus, leading to over-expression of programmed death-ligand 1 and 2. In a phase 1b study, nivolumab, a PD-1-blocking antibody, produced a high response in patients with relapsed or refractory cHL, with an acceptable safety profile. Patients and methods: We present a retrospective analysis of 82 patients (median age: 30 years; range: 18-75) with relapsed/refractory HL treated with nivolumab in a named patient program from 24 centers throughout Turkey. The median follow-up was 7 months, and the patients had a median of 5 (2-11) previous lines of therapy. Fifty-seven (70%) and 63 (77%) had been treated by stem-cell transplantation and brentuximab vedotin, respectively. Results: Among 75 patients evaluated after 12 weeks of nivolumab treatment, the objective response rate was 64%, with 16 complete responses (CR; 22%); after 16 weeks, it was 60%, with 16 (26%) patients achieving CR. Twenty patients underwent subsequent transplantation. Among 11 patients receiving allogeneic stem-cell transplantation, 5 had CR at the time of transplantation and are currently alive with ongoing response. At the time of analysis, 41 patients remained on nivolumab treatment. Among the patients who discontinued nivolumab, the main reason was disease progression (n = 19). The safety profile was acceptable, with only four patients requiring cessation of nivolumab due to serious adverse events (autoimmune encephalitis, pulmonary adverse event, and two cases of graft-versus-host disease aggravation). The 6-month overall and progression-free survival rates were 91.2% (95% confidence interval: 0.83-0.96) and 77.3% (0.66-0.85), respectively. Ten patients died during the follow-up; one of these was judged to be treatment-related. Conclusions: Nivolumab represents a novel option for patients with cHL refractory to brentuximab vedotin, and may serve as a bridge to transplantation; however, it may be associated with increased toxicity