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To integrate circuits into the organic light emitting diode displays, it is necessary to fabricate polycrystalline silicon (poly-Si) based thin-film transistors (TFTs) on the glass substrates. In this work we investigated the correlation between the electrical characteristics and the poly-Si morphology of the excimer laser annealed (ELA) TFTs in ultralow oxygen concentrations (~ ppm). The main feature of ELA poly-Si films is the protrusion at grain boundaries that makes the film surface rough. The surface roughness increases with an increasing oxygen concentration during the laser annealing and degrades the TFT characteristics in the on-state as well as the breakdown voltage of the gate insulator, while the off current is independent of process conditions. This result is attributed to the increased oxygen incorporation in the film in the case of an ELA process. Since oxygen increased the defect density in the polysilicon bandgap, controlling the oxygen concentrations in the process chamber helped to improve the performance of the ELA poly-Si TFTs. Based on these results, we discuss the relationship between performance of active matrix organic light emitting display panels and oxygen concentrations during ELA.

This study was performed to investigate the effect of gastric banding surgery on the improvement of glycated hemoglobin (HbA1c) of morbidly obese (MO) patients with type 2 diabetes mellitus (T2DM) with the consideration that obesity was associated with insulin resistance and T2DM. We retrospectively reviewed the medical records of 38 MO with T2DM patients and 50 MO patients. Pre-surgery and post-surgery data were analyzed a year later. The medical data from these patients, including sex, age, height, weight, body composition, HbA1c, triglyceride, total cholesterol, aspartate transaminase (AST), and alanine transaminase (ALT) were measured. There were significant reductions of body weight and body mass index (BMI), body fat, body fat percentage, waist-hip ratio, visceral fat, and obesity in each group before and after gastric banding surgery. Results of AST, ALT, and HbA1c had significant reductions in each group. For HbA1c, treatment rate was 71% in the MO group with T2DM with significant reduction of 22.8%. It is thought that a gastric banding surgery is one of the breakthrough methods not only for weight loss but also for the prevention of complication of the obese patients with T2DM. Thus, gastric banding surgery could be effective in controlling HbA1c in obese patients with type 2 diabetes mellitus.

Flexible copper indium gallium selenide (CIGS)-based solar cells were developed on stainless steel (STS) substrates covered with an insulating layer. The properties of the CIGS films fabricated on STS foils coated with SiO 2 -based soluble material (“sol-SiO 2 ”) were compared with those on plasma enhanced chemical vapor-deposited silicon oxide (“PE-SiO 2 ”)/MoNa/STS and SLG substrates. The decrease in compensating donor due to sufficient Na doping from the insulating layer was attributed to higher open-circuit voltage and fill factor. Furthermore, the double graded Ga composition in the CIGS films grown on the STS substrates was preserved, and the open-circuit voltage was enhanced with a minor decrease in the short-circuit current. As a result, solar cells with 14% efficiency were produced on sol-SiO 2 /STS samples with a Fe atom diffusion barrier and external Na incorporation. This was far higher than the 9.5% and 12.8% obtained from the solar cells on PE-SiO 2 /MoNa/STS and SLG, respectively.

Objective Quercetin has been reported to exert many beneficial effects on the protection against various diseases, such as diabetes, cancer, and inflammation. The aim of this study is to evaluate the potential osteogenic differentiation ability of mesenchymal stem cells in the presence of quercetin. Material and methods Quercetin-loaded poly(lactic-co-glycolic acid) microspheres were prepared using an electrospraying technique. Characterization of the microspheres was evaluated with a scanning electron microscope and release profile. Three-dimensional cell spheroids were fabricated using silicon elastomer-based concave microwells. Qualitative results of cellular viability were seen under a confocal microscope, and quantitative cellular viability was evaluated using the Cell Counting Kit-8 assay. The alkaline phosphatase activity and Alizarin Red S staining were performed. A quantitative real-time polymerase chain reaction and a western blot analysis were performed. Results Spheroids were well formed irrespective of quercetin concentration. Most of the cells in spheroids emitted green fluorescence, and the morphology was round without significant changes. The application of quercetin-loaded microspheres produced a significant increase in the alkaline phosphatase activity. The real-time polymerase chain reaction results showed a significant increase in Runx2, and western blot results showed higher expression of Runx2 protein expression. Conclusion Biodegradable microspheres loaded with quercetin produced prolonged release profiles with increased mineralization. Microspheres loaded with quercetin can be used for the enhancement of osteoblastic differentiation in cell therapy.

Flexible copper indium gallium diselenide (CIGS)-based solar cells are developed on stainless steel (STS) substrates covered with an insulating layer. The Na containing AlPO 4 (“Na-AlPO 4 ”) material is processed using the slot-die coating method. The coated film is analyzed using various spectroscopic methods including scanning electron microscopy, energy dispersive X-ray spectrometry, transmission electron microscopy, secondary-ion mass spectrometry, X-ray diffraction, and 3D profiler. The characteristics of the solar cells fabricated on these insulating films are also evaluated. The application of the Na-AlPO 4 layer on the STS substrates is compared with the electrical performance of the CIGS solar cells fabricated on metal foil. Although the insertion of the insulating layer does not influence the formation of the CIGS film and solar cell performance, a better uniformity in the current–voltage curve is obtained.

In general, the ocean wave vibration power generator consists of buoy, vibration system and linear generation system. It maximized energy efficiency by using resonance phenomenon that turned to thenatural frequency of vibration system and frequency of ocean wave energy. But it is difficult to obtain efficiently energy from ocean wave because the frequency of ocean wave changes from moment to moment. In this paper, we study the buoy and vibration system of ocean wave power generator to solve these problem. Firstly, we designed the buoy that gives rise to resonance between ocean wave and buoy. Secondly, we designed vibration system that is occurred to resonance between buoy and vibration system.And then the relative velocity between the buoy and magnetic of ocean wave vibration generator increasesand the relative displacement between buoy and ocean wave decreases at the same time. As a result, the method which is proposed in this paper has merits not only securing its stability from harsh ocean wave environment but also obtaining more kinetic energy from ever-changing ocean wave.

Background Gut hormones play a role in diabetes remission after a Roux-en-Y gastric bypass (RYGB). Our aim was to investigate differences in gut hormone secretion according to diabetes remission after surgery. Second, we aimed to identify differences in insulin secretion and sensitivity according to diabetes remission after RYGB. Methods Twenty-two severely obese patients with type 2 diabetes underwent RYGB. A meal tolerance test (MTT) was performed 12 months after RYGB. The secretions of active glucagon-like peptide-1 (active GLP-1), glucose-dependent insulinotropic peptide (GIP), peptide YY, C-peptide and insulin during the MTT test were calculated using total area under the curve values (AUC). Remission was defined as glycated haemoglobin (A1C) of

This study evaluated the effects of precursor concentration ranging from 0.06 to 1.5 M on the properties of hydrothermally grown ZnO on annealed ZnO buffered Si substrates. At relatively low concentrations (no more than 0.5 M), well-aligned ZnO arrays were grown on ZnO/Si(1 0 0) due to heterogeneous nucleation. As the concentration was increased to 1.0 M, the morphologies changed to randomly accumulated particles as a result of homogeneous nucleation. The crystal and optical properties of the materials were investigated by X-ray diffractometer (XRD) and photoluminescence (PL) measurement, respectively. It was found that the best crystal and optical properties were obtained with concentrations of 0.5 and 0.3 M, respectively. These properties were observed to degrade when the concentration was raised to more than 1.0 M.

ZnO thin films prepared by PLD method exhibit an excellent optical property, but may have some problems such as incomplete surface roughness and crystallinity. In this study, undoped ZnO buffer layers were deposited on (0001) sapphire substrates by ultra high vacuum pulse laser deposition (UHV-PLD) and molecular beam epitaxy (MBE) methods, respectively. After post annealing of ZnO buffer layer, undoped ZnO thin films were deposited under different oxygen pressure ( mtorr) conditions. The Arsenic-doped (1, 3 wt%) ZnO thin layers were deposited on the buffer layer of undoped ZnO by UHV-PLD method. The optical property of the ZnO thin films was analyzed by photoluminescence (PL) measurement. The XRD analysis exhibited a strong (002)-peak, which indicates c-axis preferred orientation. Field emission-scanning electron microscope (FE-SEM) revealed that microstructures of the ZnO thin films were varied by oxygen partial pressure, Arsenic doping concentration, and deposition method of the undoped ZnO buffer layer. The denser and smoother films were obtained when employing MBE-buffer layer under lower oxygen partial pressure. It was also found that higher Arsenic concentration gave the enhanced growing of columnar structure of the ZnO thin films.

Highly concentrated p-type ZnO thin films can be obtained by doping of N, P and As elements. In this study, undoped ZnO buffer layers were prepared on a (0001) sapphire substrate by a ultra high vaccum pulsed laser deposition(UHV-PLD) method. ZnO buffer layers were deposited with various deposition temperature() at 350 mtorr of oxygen working pressure. Arsenic doped(1 wt%) ZnO thin films were deposited on the ZnO buffer layers by UHV-PLD. Crystallinity of the samples were evaluated by X-ray diffractometer and scanning electron microscopy. Optical, electrical properties of the ZnO thin films were estimated by photoluminescence(PL) and Hall measurements. The optimal condition of the undoped ZnO buffer layer for the deposition of As-doped ZnO thin films was at of deposition temperature.

The remodeling process of bone is accompanied by complex changes in the expression levels of various genes. Several approaches have been employed to detect differentially-expressed genes in regard to osteoclast differentiation. In order to identify the genes that are involved in osteoclast differentiation, we used a cDNAarray-nylon membrane. Among 1,200 genes that showed a measurable signal, 19 genes were chosen for further study. Eleven genes were up-regulated; eight genes were downregulated. TIS21 was one of the up-regulated genes which were highly expressed in mature osteoclasts. To verify the cDNA microarray results, we carried out RT-PCR and real-time RT-PCR for the TIS21 gene. The TIS21 mRNA level was higher in differentiated-osteoclasts when compared to undifferentiated bone-marrow macrophages. Furthermore, the treatment with 1 mM of a TIS21 antisense oligonucleotide reduced the formation of osteoclasts from the bone-marrow-precursor cells by approximately 30%. These results provide evidence for the potential role of TIS21 in the differentiation of osteoclasts

The reaction of [Ru3(CO)12] with malonic acid or oxalic acid, followed by the addition of PMe3, yielded {[Ru2(CO)4(PMe3)2](μ-O2CCH2CO2)}2 (1) and {[Ru2(CO)4(PMe3)2](μ-O2CCO2)}4 (2), respectively. The molecular structures of both 1 and 2 were determined by single-crystal X-ray diffraction to reveal that 1 is a molecular loop, while 2 is the first example of molecular squares containing {Ru2(CO)4(PR3)2} building blocks.

Detailed optical characteristics of excitonic green emission/absorption in ZnSSe:Te epitaxial layers, grown by molecular beam epitaxy, were studied by photoluminescence (PL) and PL excitation measurements. Based on these optical properties, we have developed bright and long-lived green (~500 nm) light-emitting diodes (LEDs) using ZnS0.11Se0.85:Te0.04 epilayers as active layers. The ZnSSe:Te-based LEDs exhibit a fairly long device lifetime (>2000 h) when operated at 3 A/cm2 under CW condition at room temperature. The green LEDs show only slow-mode degradation, and the degradation mode is quite different from that of II–VI-based laser diodes (LDs) and LEDs employing the ZnCdSe–ZnSe system. It is confirmed that the Te-doping-induced "alloy-hardening effect" plays an important role in both efficient emission and strong suppression of the device degradation.

Bright green and blue light emitting diodes have been developed based on ZnSSe:Te active layer, with high crystal quality and a close lattice-match to GaAs substrate. The green LEDs exhibit a fairly long lifetime (>2000 h) at room temperature, which is attributable to the crystal-hardening effect by Te-doping. The devices show slow-mode degradation due to the gradual enhancement of microscopic defects in p-ZnMgSSe cladding layer. No detectable changes in dark-spot and dark-line formation due to macroscopic defects are observed during device operation.

Dislocation-free blue-green laser diodes of (ZnCd)Se/(ZnMg)(SSe) show a slow-mode degradation during device operation. This degradation is caused not by generation and propagation of macroscopic defects, but by microscopic-point defect reaction (marked enhancement in its concentration and resulting migration process) during high-density carrier-injection. It is also evidenced experimentally that the direct driving force on the marked defect reaction is derived from minority carrier injection induced e-h non-radiative recombination process at localized point defect centers in the p-type cladding layer of the LD devices.

We have investigated the optical properties of Te-doped ternary ZnSSe epilayers grown on (100) GaAs substrates by molecular-beam epitaxy for the first time. The case of ZnS x Se 1-x-y : Te y (x = 0.11, y = 0.042) specimen is represented by a good crystal quality; a good lattice matching to GaAs (Δa/a 1000 h) operated at 3 A/cm 2 (300 K).

Effects of bonding materials in a screen-printing paste on field emission properties were investigated for carbon nanotube (CNT) cathodes. The CNT cathodes were characterized for their dependence on current density in terms of the sintering behavior of the bonding material. As the diameter of the Ag particles in the bonding material decreased from 1000 nm to 10 nm, the current density of the CNT cathode increased. The sintering temperature of bonding materials was decreased for small silver (Ag) particles in bonding material. The higher current density for a CNT cathode fabricated with smaller Ag particles was primarily due to the lower sheet resistance of the bonding material after heat treatment.

Gut hormones play a role in diabetes remission after a Roux-en-Y gastric bypass (RYGB). Our aim was to investigate differences in gut hormone secretion according to diabetes remission after surgery. Second, we aimed to identify differences in insulin secretion and sensitivity according to diabetes remission after RYGB.Twenty-two severely obese patients with type 2 diabetes underwent RYGB. A meal tolerance test (MTT) was performed 12 months after RYGB. The secretions of active glucagon-like peptide-1 (active GLP-1), glucose-dependent insulinotropic peptide (GIP), peptide YY, C-peptide and insulin during the MTT test were calculated using total area under the curve values (AUC). Remission was defined as glycated haemoglobin (A(1C)) of6.5% and a fasting glucose concentration of126 mg/dL for 1 year or more without active pharmacological therapy.Of the 22 patients, 16 (73%) had diabetes remission (remission group). The secretion CURVES of active GLP-1, GIP and peptide YY were not different between the groups. AUC of insulin and C-peptide were also not different. Homeostasis model assessment estimate of insulin resistance was significantly lower (1.26 ± 1.05 versus 2.37 ± 1.08, p = 0.006), and Matsuda index of insulin sensitivity was significantly higher in the remission group (10.5 ± 6.2 versus 5.8 ± 2.1, p = 0.039). The disposition index (functional reserve of beta cells) was significantly higher in the remission group compared with that in the non-remission group (5.34 ± 2.74 versus 1.83 ± 0.70, p0.001).Remission of diabetes after RYGB is not associated with a difference in gut hormone secretion. Patients remaining diabetic had higher insulin resistance and decreased β cell functional reserve.

Our aim was to identify preoperative anthropometric and clinical parameters that predict the remission of diabetes after Roux-en-Y gastric bypass (RYGB). Fifty severely obese Korean patients with type 2 diabetes underwent RYGB. Visceral and abdominal subcutaneous fat area (SFA) was assessed using computed tomography before and 6 and 12 months after RYGB. Remission was defined as a glycated hemoglobin (A(1C)) level

Purpose: This study was planned to determine the characteristics of extremely obese patients during Bariatric surgery and to evaluate how the difference in the number of postsurgical personal nutritional educations they received affected the weight loss. Methods: This is a retrospective study on the basis of the medical records of extremely obese patients for 15 months after receiving gastric banding. A total of 60 people were selected as the study subjects and they were divided into the Less Educated Group and the More Educated Group according to the average number of personal nutritional educations they received. We investigated both groups to determine the general characteristic, health related lifestyle habits, obesity related complications and symptoms in possession, and eating habits before their surgery, the body composition measurement result, obesity determination indices at 1, 3, 6, 9, 12, and 15 months before and after their surgery, and the biochemical parameters at 6 months before and after their surgery. Results: Body fat and weight showed rapid reduction until 6 months after the surgery, but thereafter reduced slowly depending on the result of body composition measurement. Regarding body fat and weight, the More Educated Group, who received nutrition education more often, showed significantly lower levels than the Less Educated Group at 15 months after surgery. Regarding BMI and degree of obesity, the More Educated Group showed significantly lower levels than the Less Educated Group at 15 months after surgery. Here, we were assured that BMI is reversely proportional to the number of personal nutritional educations at 15 months, which is more outstanding after surgery than before surgery. Conclusion: Long-term nutritional education is a key factor for the extremely obese patient in maintaining the effects of Bariatric surgery on weight and body fat reduction onwards. In the next stage, considering the characteristics of the study subjects, adoption of individual nutrition education is recommended for postsurgical prospective arbitration of obesity in order to monitor blood pressure, obesity related complications, symptoms in possession, and how eating habits and health related life habits change, and to judge the actual effect of the nutritional education method at the same time.

A survey to evaluate the current status of bariatric and metabolic operations in Korea was conducted. Data from 5467 cases (32 hospitals) were collected. The annual numbers of bariatric and metabolic operations increased each year, from 139 in 2003 to 1686 in 2013. Adjustable gastric band (AGB, 67.2 %) was the most common operation, followed by sleeve gastrectomy (SG, 14.2 %), and Roux-en-Y gastric bypass (RYGB, 12.7 %). Mean patient age and body mass index (BMI) were 35.4 years and 35.9 kg/m2, respectively. In-hospital morbidity and mortality rates were 6 % (114/2305) and 0.25 % (5/2176), respectively. In Korea, AGB was the most common operation because of the availability and activity of specialized bariatric clinics. These national survey results established a baseline for future data collection.