Journal of reconstructive microsurgery, Jan 26, 2016
Background Epigallocatechin gallate (EGCG) is a substance abundant in green tea. In this study, t... more Background Epigallocatechin gallate (EGCG) is a substance abundant in green tea. In this study, the effects of EGCG on perforator flap viability were investigated. Methods A total of 40 rats were assigned to four groups of 10 each. In each subject, a 4 × 6 cm abdominal skin flap was raised and adapted back onto its place. In the control group, no further procedures were taken. In the flap group, 40 mg/kg/d EGCG was injected into the flap. In the gavage group, 100 mg/kg/d EGCG was given through a feeding tube. In the intraperitoneal group, 50 mg/kg/d EGCG was injected intraperitoneally. On the 7th postoperative day, flaps were photographed and the viable areas were measured and compared via a one-way analysis of variance. Results The ratios of viable and contracted flap area were 9.15/12.01, 4.59/16.46, 11.56/11.20, and 11.65/10.77 cm(2) for the control, flap group, gavage group, and intraperitoneal group, respectively. While the flap group yielded the worst results in the sense of f...
Vessel grafting is commonly used for revascularization or pedicle lengthening. Although veins are... more Vessel grafting is commonly used for revascularization or pedicle lengthening. Although veins are more commonly used, they can form aneurysms when bridging an arterial gap. This can lead to thrombosis, and the risk is increased when there is a size discrepancy. This study reports the long-term results of arterial lengthening via size discrepant carotid artery and femoral vein grafts in a rat femoral artery model (1:1.5 ratio). A total of 28 rats were used in this study, divided into two groups of 14. By the 21st day, one anastomosis in each group has been found to be thrombosed. Long-term patency rates were the same for both groups (93.3%). Radiologic imaging showed that size match in the carotid artery grafts was excellent despite of slightly fusiform dilatation, but in the vein groups, pronounced aneurismal deformation and distortion in the anastomosis was seen. Histologic analysis revealed that in the arterial grafts, endothelial continuity was smooth and mural inflammation was less than that of the vein grafts. Organized or recanalized mural thrombi were seen in 38.5% in the vein grafts, whereas in arterial grafts there were none.
Radiation of dominant plane sound wave from a semi-infinite rigid circular cylindrical pipe with ... more Radiation of dominant plane sound wave from a semi-infinite rigid circular cylindrical pipe with a perforated end is investigated rigorously by the Wiener-Hopf technique. The solution involves a set of infinitely many expansion coefficients satisfying an infinite system of ...
Abstract: Radiation of sound waves from a rigid circular cylindrical pipe with a partial internal... more Abstract: Radiation of sound waves from a rigid circular cylindrical pipe with a partial internal impedance loading is investigated rigorously by a modified version of the Wiener-Hopf technique. The solution involves a set of infinitely many expansion coefficients satisfying ...
Aft fan noise radiating from a lined bypass exhaust duct with lined afterbody is modelled in a wa... more Aft fan noise radiating from a lined bypass exhaust duct with lined afterbody is modelled in a way that allows an analytical solution of generalised Wiener-Hopf type. A preliminary set of numerically evaluated examples, based on the experiments by Tester at al. seem to confirm their conclusions that the beneficial effect of a lined afterbody is mainly found without mean flow.
ABSTRACT In this study, the novel tetra nonperipherally α-substituted 1(4), 8(11), 15(18), 22(25)... more ABSTRACT In this study, the novel tetra nonperipherally α-substituted 1(4), 8(11), 15(18), 22(25)-tetrakis undecyloxy phthalocyanine derivatives bearing 1-dodecanol moiety, M{Pc[O–(CH2)11CH3)]4 (MCo(2), Zn(3), Cu(4), Mn(5))}, (Pc: Phthalocyanine) have been synthesized for the first time and their structures characterized by using 1H NMR, 13C NMR, FT-IR, MALDI-TOF/MS, UV–vis spectral and elemental analysis. Also Surface morphology of phthalocyanine complexes were investigated by atomic force microscope (AFM) as complementary technic. The new synthesized complexes are soluble in both polar solvents, such as THF and DMF, and nonpolar solvents such as CHCl3, CH2Cl2, benzene and hexane. An organic thin film transistor (OTFT) or organic field effect transistor (OFET), based on novel cobalt phthalocyanine (CoPc) was fabricated with SiO2 as the gate dielectric material. We have also investigated electrical characterization of the OTFT of the new synthesis CoPc layer and composite semiconductor material. While Au was deposited as gate contact, source and drain contacts of the device were coated with Ag by using thermal evaporation method. CoPc layer was prepared with spin coater method. Our study has shown that the new synthesis CoPc make a noteworthy on the OTFT. The CoPc OTFT exhibited saturation at the order of μFET of 2,01 × 10−1 cm2/V s. Ion/Ioff and VT of this device are 2 × 102 and −2,25 V, respectively.
Clinical and experimental obstetrics & gynecology, 2014
To evaluate agreement of conventional sperm analysis with computer-aided semen analysis (CASA) re... more To evaluate agreement of conventional sperm analysis with computer-aided semen analysis (CASA) regarding concentration, motility, and morphology using samples from infertile men. In this study a total of 195 male partners of couples who underwent evaluation of infertility were included. All semen samples were examined by conventional method and CASA in terms of morphology, motility, and concentration. Pearson correlation analysis and the Bland-Altman method were used to assess correlation and agreement between conventional semen analysis and CASA measurements. When the two methods were compared in terms of concentration, motility, and morphology, there was a statistically significant correlation in all variables. The best correlation was obtained for sperm concentration. However, there was a poor correlation for sperm morphology between conventional method and CASA. Sperm concentration and morphology obtained by CASA were 14% and 87% lower, respectively; motility was 21% higher than...
The European Journal of Contraception and Reproductive Health Care, 2014
OBJECTIVES To evaluate the predictive value of uterine artery Doppler characteristics in predicti... more OBJECTIVES To evaluate the predictive value of uterine artery Doppler characteristics in predicting copper intrauterine device (IUD)-induced side effects such as dysmenorrhoea and menorrhagia, and worsening of dyspareunia. METHODS One hundred and twenty regularly menstruating women were enrolled in the study. All underwent transvaginal uterine artery Doppler analysis in the early follicular phase, on two occasions: before insertion of the IUD, and six months after insertion. Pre- and post-insertion resistance (RI) and pulsatility (PI) indices of the uterine arteries were measured. Doppler parameters were compared between subjects experiencing an increase in IUD-mediated side effects and those reporting no change. RESULTs RI and PI of all participants before and after IUD insertion were not significantly different (0.75 ± 0.06 vs. 0.74 ± 0.09, p = 0.49; 1.81 ± 0.55 vs. 1.83 ± 0.70, p = 0.7, respectively). No significant difference was found in the comparison of pre- and post-insertion PI and RI values of women who had increased- and those who experienced no change in dysmenorrhoea, dyspareunia and duration/amount of menstruation. CONCLUSIONS No major changes in uterine blood flow were observed in women experiencing increased menstrual bleeding, dyspareunia or dysmenorrhoea after insertion of a copper IUD. The occurrence of these effects cannot be predicted by prior Doppler flow analysis.
Bu çalışma Satın Alma Gücü Paritesi (SAGP) kuramını Türkiye ile en yüksek dış ticaret hacmine sah... more Bu çalışma Satın Alma Gücü Paritesi (SAGP) kuramını Türkiye ile en yüksek dış ticaret hacmine sahip beş ülke (ABD, Almanya, Fransa, Italya ve Ingiltere) için 1969-1996 dönemi için test etmek amacındadır. Yöntem olarak birim kök (unit root) ve birlikte bütünleşme (cointegration) kullanılmıştır. Uygulama sonuçları 1969-1996 döneminde, SAGP kuramının Türkiye ile Almanya ve Fransa arasında geçerli olduğunu ortaya koyarken, ABD, Italya
ABSTRACT To determine whether embryos having all top qualified both on Day 3 and Day 5 have highe... more ABSTRACT To determine whether embryos having all top qualified both on Day 3 and Day 5 have higher pregnancy rates than the oth- ers. The study included 143 consecutive cycles were recruited in which Day 5 embryo transfer was available. Cleavage stage embryos were graded according to 1 to 4 scoring system, based on fragmentation, cell symmetry, and blastomere num- ber. Among cleavage stage embryos, Grade 1 and Grade 2a/2b were further stratified as 'top quality' embryos to be transferred, others were defined as control group. Blastocyst stage embryos were graded from 1 to 6 according to intracellular mass (ICM) and trophec- toderm (TE). Day 5 fresh embryo transfer was performed in all cases using soft catheter. Positive pregnancy test was accepted when serum beta-human chorionic gonadotrophin (1-hCG) exceeded 20 mIU/ml. On the cleavage stage, top quality embryo was available in 47 of 143(32.9%) cases. Of the 47 embryos, the number of cases reaching any Grade 4, 3 quality, and early blastocyst on Day 5 were 22 (46.8%), 15 (31.9%), and 10 (21.3%). The respective figures on the control group (n = 96) were 33 (34.4%), 37 (38.5%), and 26 (27.1%) (p > 0.05). The pregnancy rates were also similar. All top qualified embryos both on Day 3 and 5 did not reveal higher pregnancy rate than the others.
The question of what determines the quantity of resources a country devotes to medical care conti... more The question of what determines the quantity of resources a country devotes to medical care continues to get attention from researchers and policy makers. Many of the studies find that there is a strong and positive correlation between the gross domestic product (GDP) of a country and the national expenditure on health care (HCE) . Most of these studies use a demand function approach to specify their model in which real per capita HCE is expressed as a function of real per capita income (GDP) and other selected variables. For example, Newhouse [18] reports that a large proportion (92) of variation in HCE per person can be explained by variations in level of national income per person. Use of expenditure data at the national level may help policy makers to plan health reforms, allocate the resources efficiently, and assess the impact of these reforms on the economy. Most studies also calculate the income elasticity of HCE and report an income elasticity greater than 1, implying that medical care is deemed to be a luxury good.
Au/poly(propylene glycol)-b-polystyrene/n-Si (D1) and Au/poly(propylene glycol)-b-polystyrene(HAu... more Au/poly(propylene glycol)-b-polystyrene/n-Si (D1) and Au/poly(propylene glycol)-b-polystyrene(HAuCl 4 dispersed)/n-Si (D2) diodes were fabricated and their response to UV illumination was investigated using current-voltage measurements in dark and under various illumination intensities (50-250 mW/cm 2 ). Scanning Electron Microscope micrographs of the diodes were provided for morphological analysis. Main electrical parameters; such as ideality factor, barrier height and reverse saturation current, are calculated using Thermionic Emission and Norde's method, and it was found that they show dependence on UV illumination. Ideality factor values of D1 and D2 diodes in dark is 2.53 and 2.29 whereas they are 3.37 and 3.39 under 100 mW/cm 2 UV illumination, respectively. A noticeable effect of UV illumination is the considerable increase of current in the reverse bias region compared with current in dark such that current value increases by $10 3 times with 100 mW/cm 2 UV illumination for both diodes. Furthermore, density distribution profiles of surface states in these diodes were also investigated.
Bu çalışmada sızıntı suyu geri devirli olarak işletilen depo sahalarında aerobik ve anaerobik ayr... more Bu çalışmada sızıntı suyu geri devirli olarak işletilen depo sahalarında aerobik ve anaerobik ayrışma süreçlerinin belirlenmesi amacıyla 1 m yüksekliğinde ve 40 cm çapında laboratuar ölçekli, iki adet reaktöre İstanbul kentsel katı atıklarını temsil edecek şekilde atıklar yerleştirildikten sonra, sızıntı suyu bileşenleri izlenerek havalandırmanın atık stabilizasyonu üzerindeki etkileri tespit edilmiştir. Biri aerobik diğeri anaerobik olarak işletilen reaktörlerin tabanında bulunan sızıntı suyu musluklarından haftalık olarak alınan numunelerde pH, ORP, Alkalinite, Klorür ve KOI parametreleri izlenmiştir Havalandırmanın depo sahalarında atık ayrışmasını hızlandırdığı, ve yüksek kirletici yüküne sahip sızıntı suyu kalitesini iyileştirdiği gözlenmiştir.
Radiation of sound from a simplified model of a buried nozzle with bypass flow is studied. More p... more Radiation of sound from a simplified model of a buried nozzle with bypass flow is studied. More precisely, a semi-infinite duct (the inner nozzle) is situated inside a larger semi-infinite duct. The exit plane of the larger duct either coincides with the exit plane of the smaller duct, or extends beyond it. Differences in the piece-wise subsonic mean flow velocity, density and temperature are taken into account. The inner nozzle issues the core flow inside the bypass jet flow. The bypass nozzle issues the bypass jet flow inside the ambient co-flow. Two vortex sheets, attached to the duct exits, separate the different flows from each other. These vortex sheets are unstable due to this mean velocity discontinuity. The application of the Kutta condition at the respective trailing edges guarantees shedding of vorticity which excites these instabilities. The system is set up to respond to an incident annular duct mode, but the analysis would be very similar for an inner duct mode.
Analytical solutions for the problem of radiation of sound from a duct with flow have been shown ... more Analytical solutions for the problem of radiation of sound from a duct with flow have been shown to serve as an important first model for acoustic engine-aircraft engineering applications, useful for understanding the physics and for validating and benchmarking numerical solutions.
Aim: The aim of the study was to evaluate how obesity effects the coagulation and fibrinolytic sy... more Aim: The aim of the study was to evaluate how obesity effects the coagulation and fibrinolytic system in the postmenopausal period. Method: Forty-eight obese (body mass index (BMI) ≥30 kg/m 2 ) and 38 nonobese (BMI < 30 kg/m 2 ) postmenopausal women were enrolled in the study. Fat mass and insulin resistance were calculated. Plasma levels of plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA), D-dimer, thrombomodulin, and thrombin activatable fibrinolysis inhibitor (TAFI) antigen were determined by ELISA method. TAFI activity was measured using the chromogenic assay. Results: Obese subjects had higher PAI-1 (73.5 ± 35.7 ng/mL vs. 57.1 ± 34.2 ng/mL, p < 0.05) levels but lower tPA/PAI-1 ratio (0.59 ± 0.50 vs. 38 ± 0.21, p < 0.05) than their nonobese counterparts. Obesity was not statistically significant for other haemostatic variables. BMI and fat mass were positively correlated with PAI-1 (r = 0.312, p = 0.003; r = 0.381, p = 0.005, respectively) and negatively correlated with tPA/PAI-1 ratio (r = −0.273, p = 0.01; r = −0.545, p = 0.01, respectively). HOMA scores were also positively correlated with PAI-1 levels (r = 0.236, p = 0.04). Conclusion: We found that tendency to hypercoagulability in the postmenopausal women was due to increased PAI-1 rather than TAFI levels, which may contribute to adverse cardiovascular outcomes in this cohort. Further studies should be undertaken to evaluate effects of weight loss on the coagulation and fibrinolytic system.
Journal of reconstructive microsurgery, Jan 26, 2016
Background Epigallocatechin gallate (EGCG) is a substance abundant in green tea. In this study, t... more Background Epigallocatechin gallate (EGCG) is a substance abundant in green tea. In this study, the effects of EGCG on perforator flap viability were investigated. Methods A total of 40 rats were assigned to four groups of 10 each. In each subject, a 4 × 6 cm abdominal skin flap was raised and adapted back onto its place. In the control group, no further procedures were taken. In the flap group, 40 mg/kg/d EGCG was injected into the flap. In the gavage group, 100 mg/kg/d EGCG was given through a feeding tube. In the intraperitoneal group, 50 mg/kg/d EGCG was injected intraperitoneally. On the 7th postoperative day, flaps were photographed and the viable areas were measured and compared via a one-way analysis of variance. Results The ratios of viable and contracted flap area were 9.15/12.01, 4.59/16.46, 11.56/11.20, and 11.65/10.77 cm(2) for the control, flap group, gavage group, and intraperitoneal group, respectively. While the flap group yielded the worst results in the sense of f...
Vessel grafting is commonly used for revascularization or pedicle lengthening. Although veins are... more Vessel grafting is commonly used for revascularization or pedicle lengthening. Although veins are more commonly used, they can form aneurysms when bridging an arterial gap. This can lead to thrombosis, and the risk is increased when there is a size discrepancy. This study reports the long-term results of arterial lengthening via size discrepant carotid artery and femoral vein grafts in a rat femoral artery model (1:1.5 ratio). A total of 28 rats were used in this study, divided into two groups of 14. By the 21st day, one anastomosis in each group has been found to be thrombosed. Long-term patency rates were the same for both groups (93.3%). Radiologic imaging showed that size match in the carotid artery grafts was excellent despite of slightly fusiform dilatation, but in the vein groups, pronounced aneurismal deformation and distortion in the anastomosis was seen. Histologic analysis revealed that in the arterial grafts, endothelial continuity was smooth and mural inflammation was less than that of the vein grafts. Organized or recanalized mural thrombi were seen in 38.5% in the vein grafts, whereas in arterial grafts there were none.
Radiation of dominant plane sound wave from a semi-infinite rigid circular cylindrical pipe with ... more Radiation of dominant plane sound wave from a semi-infinite rigid circular cylindrical pipe with a perforated end is investigated rigorously by the Wiener-Hopf technique. The solution involves a set of infinitely many expansion coefficients satisfying an infinite system of ...
Abstract: Radiation of sound waves from a rigid circular cylindrical pipe with a partial internal... more Abstract: Radiation of sound waves from a rigid circular cylindrical pipe with a partial internal impedance loading is investigated rigorously by a modified version of the Wiener-Hopf technique. The solution involves a set of infinitely many expansion coefficients satisfying ...
Aft fan noise radiating from a lined bypass exhaust duct with lined afterbody is modelled in a wa... more Aft fan noise radiating from a lined bypass exhaust duct with lined afterbody is modelled in a way that allows an analytical solution of generalised Wiener-Hopf type. A preliminary set of numerically evaluated examples, based on the experiments by Tester at al. seem to confirm their conclusions that the beneficial effect of a lined afterbody is mainly found without mean flow.
ABSTRACT In this study, the novel tetra nonperipherally α-substituted 1(4), 8(11), 15(18), 22(25)... more ABSTRACT In this study, the novel tetra nonperipherally α-substituted 1(4), 8(11), 15(18), 22(25)-tetrakis undecyloxy phthalocyanine derivatives bearing 1-dodecanol moiety, M{Pc[O–(CH2)11CH3)]4 (MCo(2), Zn(3), Cu(4), Mn(5))}, (Pc: Phthalocyanine) have been synthesized for the first time and their structures characterized by using 1H NMR, 13C NMR, FT-IR, MALDI-TOF/MS, UV–vis spectral and elemental analysis. Also Surface morphology of phthalocyanine complexes were investigated by atomic force microscope (AFM) as complementary technic. The new synthesized complexes are soluble in both polar solvents, such as THF and DMF, and nonpolar solvents such as CHCl3, CH2Cl2, benzene and hexane. An organic thin film transistor (OTFT) or organic field effect transistor (OFET), based on novel cobalt phthalocyanine (CoPc) was fabricated with SiO2 as the gate dielectric material. We have also investigated electrical characterization of the OTFT of the new synthesis CoPc layer and composite semiconductor material. While Au was deposited as gate contact, source and drain contacts of the device were coated with Ag by using thermal evaporation method. CoPc layer was prepared with spin coater method. Our study has shown that the new synthesis CoPc make a noteworthy on the OTFT. The CoPc OTFT exhibited saturation at the order of μFET of 2,01 × 10−1 cm2/V s. Ion/Ioff and VT of this device are 2 × 102 and −2,25 V, respectively.
Clinical and experimental obstetrics & gynecology, 2014
To evaluate agreement of conventional sperm analysis with computer-aided semen analysis (CASA) re... more To evaluate agreement of conventional sperm analysis with computer-aided semen analysis (CASA) regarding concentration, motility, and morphology using samples from infertile men. In this study a total of 195 male partners of couples who underwent evaluation of infertility were included. All semen samples were examined by conventional method and CASA in terms of morphology, motility, and concentration. Pearson correlation analysis and the Bland-Altman method were used to assess correlation and agreement between conventional semen analysis and CASA measurements. When the two methods were compared in terms of concentration, motility, and morphology, there was a statistically significant correlation in all variables. The best correlation was obtained for sperm concentration. However, there was a poor correlation for sperm morphology between conventional method and CASA. Sperm concentration and morphology obtained by CASA were 14% and 87% lower, respectively; motility was 21% higher than...
The European Journal of Contraception and Reproductive Health Care, 2014
OBJECTIVES To evaluate the predictive value of uterine artery Doppler characteristics in predicti... more OBJECTIVES To evaluate the predictive value of uterine artery Doppler characteristics in predicting copper intrauterine device (IUD)-induced side effects such as dysmenorrhoea and menorrhagia, and worsening of dyspareunia. METHODS One hundred and twenty regularly menstruating women were enrolled in the study. All underwent transvaginal uterine artery Doppler analysis in the early follicular phase, on two occasions: before insertion of the IUD, and six months after insertion. Pre- and post-insertion resistance (RI) and pulsatility (PI) indices of the uterine arteries were measured. Doppler parameters were compared between subjects experiencing an increase in IUD-mediated side effects and those reporting no change. RESULTs RI and PI of all participants before and after IUD insertion were not significantly different (0.75 ± 0.06 vs. 0.74 ± 0.09, p = 0.49; 1.81 ± 0.55 vs. 1.83 ± 0.70, p = 0.7, respectively). No significant difference was found in the comparison of pre- and post-insertion PI and RI values of women who had increased- and those who experienced no change in dysmenorrhoea, dyspareunia and duration/amount of menstruation. CONCLUSIONS No major changes in uterine blood flow were observed in women experiencing increased menstrual bleeding, dyspareunia or dysmenorrhoea after insertion of a copper IUD. The occurrence of these effects cannot be predicted by prior Doppler flow analysis.
Bu çalışma Satın Alma Gücü Paritesi (SAGP) kuramını Türkiye ile en yüksek dış ticaret hacmine sah... more Bu çalışma Satın Alma Gücü Paritesi (SAGP) kuramını Türkiye ile en yüksek dış ticaret hacmine sahip beş ülke (ABD, Almanya, Fransa, Italya ve Ingiltere) için 1969-1996 dönemi için test etmek amacındadır. Yöntem olarak birim kök (unit root) ve birlikte bütünleşme (cointegration) kullanılmıştır. Uygulama sonuçları 1969-1996 döneminde, SAGP kuramının Türkiye ile Almanya ve Fransa arasında geçerli olduğunu ortaya koyarken, ABD, Italya
ABSTRACT To determine whether embryos having all top qualified both on Day 3 and Day 5 have highe... more ABSTRACT To determine whether embryos having all top qualified both on Day 3 and Day 5 have higher pregnancy rates than the oth- ers. The study included 143 consecutive cycles were recruited in which Day 5 embryo transfer was available. Cleavage stage embryos were graded according to 1 to 4 scoring system, based on fragmentation, cell symmetry, and blastomere num- ber. Among cleavage stage embryos, Grade 1 and Grade 2a/2b were further stratified as &#39;top quality&#39; embryos to be transferred, others were defined as control group. Blastocyst stage embryos were graded from 1 to 6 according to intracellular mass (ICM) and trophec- toderm (TE). Day 5 fresh embryo transfer was performed in all cases using soft catheter. Positive pregnancy test was accepted when serum beta-human chorionic gonadotrophin (1-hCG) exceeded 20 mIU/ml. On the cleavage stage, top quality embryo was available in 47 of 143(32.9%) cases. Of the 47 embryos, the number of cases reaching any Grade 4, 3 quality, and early blastocyst on Day 5 were 22 (46.8%), 15 (31.9%), and 10 (21.3%). The respective figures on the control group (n = 96) were 33 (34.4%), 37 (38.5%), and 26 (27.1%) (p &gt; 0.05). The pregnancy rates were also similar. All top qualified embryos both on Day 3 and 5 did not reveal higher pregnancy rate than the others.
The question of what determines the quantity of resources a country devotes to medical care conti... more The question of what determines the quantity of resources a country devotes to medical care continues to get attention from researchers and policy makers. Many of the studies find that there is a strong and positive correlation between the gross domestic product (GDP) of a country and the national expenditure on health care (HCE) . Most of these studies use a demand function approach to specify their model in which real per capita HCE is expressed as a function of real per capita income (GDP) and other selected variables. For example, Newhouse [18] reports that a large proportion (92) of variation in HCE per person can be explained by variations in level of national income per person. Use of expenditure data at the national level may help policy makers to plan health reforms, allocate the resources efficiently, and assess the impact of these reforms on the economy. Most studies also calculate the income elasticity of HCE and report an income elasticity greater than 1, implying that medical care is deemed to be a luxury good.
Au/poly(propylene glycol)-b-polystyrene/n-Si (D1) and Au/poly(propylene glycol)-b-polystyrene(HAu... more Au/poly(propylene glycol)-b-polystyrene/n-Si (D1) and Au/poly(propylene glycol)-b-polystyrene(HAuCl 4 dispersed)/n-Si (D2) diodes were fabricated and their response to UV illumination was investigated using current-voltage measurements in dark and under various illumination intensities (50-250 mW/cm 2 ). Scanning Electron Microscope micrographs of the diodes were provided for morphological analysis. Main electrical parameters; such as ideality factor, barrier height and reverse saturation current, are calculated using Thermionic Emission and Norde's method, and it was found that they show dependence on UV illumination. Ideality factor values of D1 and D2 diodes in dark is 2.53 and 2.29 whereas they are 3.37 and 3.39 under 100 mW/cm 2 UV illumination, respectively. A noticeable effect of UV illumination is the considerable increase of current in the reverse bias region compared with current in dark such that current value increases by $10 3 times with 100 mW/cm 2 UV illumination for both diodes. Furthermore, density distribution profiles of surface states in these diodes were also investigated.
Bu çalışmada sızıntı suyu geri devirli olarak işletilen depo sahalarında aerobik ve anaerobik ayr... more Bu çalışmada sızıntı suyu geri devirli olarak işletilen depo sahalarında aerobik ve anaerobik ayrışma süreçlerinin belirlenmesi amacıyla 1 m yüksekliğinde ve 40 cm çapında laboratuar ölçekli, iki adet reaktöre İstanbul kentsel katı atıklarını temsil edecek şekilde atıklar yerleştirildikten sonra, sızıntı suyu bileşenleri izlenerek havalandırmanın atık stabilizasyonu üzerindeki etkileri tespit edilmiştir. Biri aerobik diğeri anaerobik olarak işletilen reaktörlerin tabanında bulunan sızıntı suyu musluklarından haftalık olarak alınan numunelerde pH, ORP, Alkalinite, Klorür ve KOI parametreleri izlenmiştir Havalandırmanın depo sahalarında atık ayrışmasını hızlandırdığı, ve yüksek kirletici yüküne sahip sızıntı suyu kalitesini iyileştirdiği gözlenmiştir.
Radiation of sound from a simplified model of a buried nozzle with bypass flow is studied. More p... more Radiation of sound from a simplified model of a buried nozzle with bypass flow is studied. More precisely, a semi-infinite duct (the inner nozzle) is situated inside a larger semi-infinite duct. The exit plane of the larger duct either coincides with the exit plane of the smaller duct, or extends beyond it. Differences in the piece-wise subsonic mean flow velocity, density and temperature are taken into account. The inner nozzle issues the core flow inside the bypass jet flow. The bypass nozzle issues the bypass jet flow inside the ambient co-flow. Two vortex sheets, attached to the duct exits, separate the different flows from each other. These vortex sheets are unstable due to this mean velocity discontinuity. The application of the Kutta condition at the respective trailing edges guarantees shedding of vorticity which excites these instabilities. The system is set up to respond to an incident annular duct mode, but the analysis would be very similar for an inner duct mode.
Analytical solutions for the problem of radiation of sound from a duct with flow have been shown ... more Analytical solutions for the problem of radiation of sound from a duct with flow have been shown to serve as an important first model for acoustic engine-aircraft engineering applications, useful for understanding the physics and for validating and benchmarking numerical solutions.
Aim: The aim of the study was to evaluate how obesity effects the coagulation and fibrinolytic sy... more Aim: The aim of the study was to evaluate how obesity effects the coagulation and fibrinolytic system in the postmenopausal period. Method: Forty-eight obese (body mass index (BMI) ≥30 kg/m 2 ) and 38 nonobese (BMI < 30 kg/m 2 ) postmenopausal women were enrolled in the study. Fat mass and insulin resistance were calculated. Plasma levels of plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA), D-dimer, thrombomodulin, and thrombin activatable fibrinolysis inhibitor (TAFI) antigen were determined by ELISA method. TAFI activity was measured using the chromogenic assay. Results: Obese subjects had higher PAI-1 (73.5 ± 35.7 ng/mL vs. 57.1 ± 34.2 ng/mL, p < 0.05) levels but lower tPA/PAI-1 ratio (0.59 ± 0.50 vs. 38 ± 0.21, p < 0.05) than their nonobese counterparts. Obesity was not statistically significant for other haemostatic variables. BMI and fat mass were positively correlated with PAI-1 (r = 0.312, p = 0.003; r = 0.381, p = 0.005, respectively) and negatively correlated with tPA/PAI-1 ratio (r = −0.273, p = 0.01; r = −0.545, p = 0.01, respectively). HOMA scores were also positively correlated with PAI-1 levels (r = 0.236, p = 0.04). Conclusion: We found that tendency to hypercoagulability in the postmenopausal women was due to increased PAI-1 rather than TAFI levels, which may contribute to adverse cardiovascular outcomes in this cohort. Further studies should be undertaken to evaluate effects of weight loss on the coagulation and fibrinolytic system.
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