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Despite the improved conversion efficiency of Cu2(ZnSn)Se4 (CZTSe) solar cells, their roll-to-roll fabrication nonetheless leads to low performance. The selenization time and temperature are typically considered major parameters for a powder-based CZTSe film; meanwhile, the importance of the densification during the roll-to-roll process is often overlooked. The densification process is related to the porosity of the light-absorbing layer, where high porosity lowers cell performance. In this study, we fabricated a dense CZTSe absorber layer as a method of controlling the compression of a powder precursor (Cu1.7(Zn1.2Sn1.0)S4.0 (CZTS)) during the roll-press process. The increased particle packing density of the CZTS layer was crucial in sintering the powder layer into a dense film and preventing severe selenization of the Mo back electrode. The pressed absorber layer of the CZTSe solar cell exhibited a more uniform chemical composition determined using dynamic secondary ion mass spectrometry (SIMS). Under the AM 1.5G illumination condition, the power conversion efficiency of the pressed solar cell was 6.82%, while the unpressed one was 4.90%.

Cu(In,Ga)Se2 thin films have been used as a light absorbing layer in high-efficiency solar cells. Among many methods, the powder process for fabricating Cu(In,Ga)Se2 thin films is advantageous, due to its simplicity and minimal usage of materials. However, Cu(In,Ga)Se2 layers produced by the powder process often result in high porosity and small grain sizes, which has been a significant barrier to wide application. In this report, we demonstrate that simple compression of the Cu(In,Ga)S2 powder coat and a cost-efficient selenization using a mixture of Se and Al2O3 can reduce porosity and enlarge the grain size. It is surmised that improved particle packing density in the powder coats, in addition to sintering with a steady supply of Se vapor, synergistically enhances highly sintered Cu(In,Ga)Se2 thin films.

Stable isotope ratios have been reported to be potential biomarkers of dietary intake and nutritional status. High serum levels of leptin, a hormone which regulates energy metabolism and food intake, are associated with insulin resistance and metabolic syndrome. However, little is known about the association between stable isotope ratios and the metabolic risk in humans. We investigated whether the carbon and nitrogen stable isotope ratios in hair are associated with serum leptin levels. Hair samples were collected from 399 healthy adults (233 men and 166 women) aged 40 to 70 years of a community-based cohort in Korea and the bulk stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) were measured for all hair samples. Serum leptin levels were analyzed by radioimmunoassay. δ15N showed positive correlations with serum leptin levels. In multivariate models, increasing δ15N were associated with elevated serum leptin levels (defined as ≥ the median values), whereas δ13C were not significantly associated with serum leptin levels. The odds ratio (95% confidence interval) per 1‰ increase in δ15N for an elevated serum leptin level was 1.58 (1.11-2.26). In participants with high body mass index, δ15N showed positive associations with serum leptin levels, whereas these associations were not seen in participants with low body mass index. The nitrogen stable isotopic ratio in hair is positively associated with serum leptin levels. The hair δ15N could be used as a clinical marker to estimate metabolic risk.

Precipitation and re-precipitation of metal ions has been carried out from original and supernatant solution producing Bi 3+ – Eu 3+ doped Y 2 O 3 :Eu 3+ and Eu 3+ /Tb 3+ doped Y 2 O 3 , respectively. Shorter reaction time is unable to consume all metal ions present in the solution which can be utilized through re-precipitation process. The doping of Bi 3+ – Eu 3+ in Y 2 O 3 helps to absorb maximum UV light. The activation of Y 2 O 3 matrix by Bi 3+ and Eu 3+ ions, together and separately, were studied considering the excitation energy transfer to the luminescence centers. The successful replacement of Y 3+ by RE 3+ ions can help for fine tuning of emission wavelength. Re-precipitation of supernatant solution by adding terbium precursor can successively produce uniform sized Tb 3+ doped Y 2 O 3 :Eu 3+ . The re-precipitation of the supernatant solution ensures maximum consumption of metal ions for higher product yield and possible fine tuning of emission wavelengths.

Properties of the quantum-cutting phosphors are dependent on various factors such as dopant concentration, crystallinity, homogeneity, particle size and surface morphology. Effective control of the above parameters can enhance the quantum-cutting ability of the phosphor material. Nano-sized particles of Y2O3:Tb3+,Yb3+ were prepared with a solution-based co-precipitation method and subsequent calcination. Effective control of the reaction parameters and doping concentration helped to produce uniform nanostructures with high quantum-cutting efficiency up to 181.1 %. The energy transfer mechanism between Tb3+ and Yb3+ was studied by considering their spectroscopic properties and time-resolved spectroscopy. The high efficiency and small particle size of the quantum-cutting phosphor Y2O3:Tb3+,Yb3+ make it a suitable candidate for its application in solar cells.

Kesterite Cu2ZnSnSe4 (CZTSe) thin films prepared by the selenization of mechanochemically synthe- sized Cu2ZnSnS4 (CZTS) nanocrystal films are systematically investigated as a function of the annealing time in terms of the phase purity, microstructure, composition, and device characteristics. It is shown that selenization for an extended time does not cause a noticeable amount of Sn loss or segregation of Zn-rich layers. Thus, the prolonged annealing leads to improvements (reduction) in the shunt conductance, reverse saturation current, and diode ideality factor. However, it also leads to a deterioration of the series resistance, of which influence turned out to overwhelm all of the aforementioned positive effects on the device performance. As a consequence, the CZTSe solar cell exhibits its highest efficiency (5.43%) at the shortest annealing time (10 min). Impedance spectroscopy is demonstrated to be of good use in detecting the change in the back contact of CZTSe solar cells during annealing. The impedance spectra of the CZTSe solar cells are analyzed in association with the microstructures of the back-contact electrodes, demonstrating that the increase in the series resistance is attributed to the formation of the resistive MoSe2 layer.

The synthesis of pure and rare-earth doped gallium oxide (β-Ga₂O₃) nanoparticles is reported. The synthesized nanoparticles are characterized with XRD, TEM, and PL analyses. Strong blue emission is observed from un-doped gallium oxide nanoparticles, while nanoparticles doped with Eu 3+ and Tb 3+ give strong red and green emissions, respectively. When doped with Eu 3+ and Tb 3+ together, gallium oxide nanoparticles emit white light. The CIE co-ordinate of the emitted light was found to be (0.33, 0.33), which is well within the white light region.

Aims The aim of this study was to investigate the association between serum adiponectin level and new-onset hypertension, and the relative contribution of obesity and low serum adiponectin levels to the development of hypertension in normotensive men and women. Methods We analyzed 1553 adults (584 men and 969 women) without hypertension, aged 40–70 years, who had participated in a cohort study in both time periods from 2005 to 2008 for baseline and 2008 to 2011 for follow-up. We divided participants into sex-specific tertiles according to serum adiponectin levels. We defined the highest tertile of serum adiponectin as ‘high adiponectin’. Participants were then stratified into four groups: the non-obese with high adiponectin; the non-obese with low adiponectin; the obese with high adiponectin; and the obese with low adiponectin. Results During an average of 2.6 years of follow-up, 79 men (13.5%) and 99 women (10.2%) developed hypertension. Low serum adiponectin level was an independent predictor of new-onset hypertension in men (Odds Ratio[OR]: 1.99; 95% CI: 1.03–3.86). The Obese men with low adiponectin had an increased risk of new-onset hypertension compared with the control group (OR: 2.80; 95% CI: 1.35–5.81). In postmenopausal women, the obese subjects with low adiponectin had an increased risk of new-onset hypertension compared with the control group (OR: 2.41; 95% CI 1.16–5.04). Conclusion Low serum adiponectin levels were associated with an increased risk of new-onset hypertension in men and postmenopausal women.

Monodispersed spherical silica nanoparticles synthesized by the Stober process contain large amounts of impurities and adsorbed- and structural water which cause structural and thermal instability of the microspheres. Proper heat treatment was applied to remove the impurities and water endowing the particles with high thermal and structural stability suitable for post-processes. Intrinsic changes of as-prepared silica particles during heat treatment at 550 °C were thoroughly examined by TGA, FT-IR, SAXS, TEM and SEM characterization. The annealed silica particles became much more reliable building blocks for a self-assembled thin film, as evidenced by low crack/defect density in the fabricated film. In this paper, we provide a method of stabilizing silica particles and thereby aligning them into a close packed structure without macroscopic defects. This method is potentially useful for the delicate silica alignment for patterning and fabrication of high-quality photonic crystals adequate for optical switches, wave-guides, lasers and antireflective films for solar cells.

Tungsten-doped TiO2 nanopowders (W-TiO2) were prepared by chemical vapor synthesis and the effects of a post-heat treatment on their physical, surface, and photocatalytic properties were investigated. The W-TiO2 nanopowders containing about 1.0 mol % of tungsten were obtained and annealed from 400 to 700 °C. The as-synthesized and annealed W-TiO2 nanopowders were carefully examined for their crystalline and opto-electronic structure and morphology by means of X-ray diffraction, UV–Vis spectroscopy, and transmission electron microscopy. In addition, the surface condition was investigated by X-ray photoelectron spectroscopy. The photocatalytic activities were studied by the oxidative degradation of 2-propanol under UV light irradiation. We found that the photocatalytic activity of W-TiO2 varied significantly with the temperature of the heat treatment, exceeding the performance of P25 after annealing at 600 °C. Interestingly, the chemical composition of titanium and tungsten of W-TiO2 played a crucial role to its photocatalytic activity as the mixed valence states, Ti n+ (n = 4, 3, 2, 0) and W n+ (n = 6, 5, 4), were found in accordance with altering the annealing temperature.

Cu(In,Ga)Se2 (CIGS) is a compound semiconductor and is one of the most attractive light-absorbing materials for use in thin film solar cells. Among the various approaches to prepare CIGS thin films, the powder process offers an extremely simple and materials-efficient method. Here, we report the mechano-chemical preparation of CIGS compound powders suitable for fabrication of CIGS films by a powder process. We found that the CIGS phase was formed from the elemental powders of Cu, In, and Se and liquid Ga using high energy milling process with a milling time as short as 40 min at 200 rpm due to a self-accelerating exothermic reaction. The morphology and size of the CIGS powders changed with a function of the milling speed (100-300 rpm), leading to an optimal condition of milling at 200 rpm for 120 min. We also found that it was difficult to obtain a monolithic phase of the CIGS powders without severe particle aggregation by mechano-chemical milling alone. Therefore, in combination with the milling, subsequent heat-treatment at 300 degrees C was performed, which successfully provided monolithic CIGS nanopowders suitable for powder process. When a thin film was fabricated from the monolithic CIGS nanopowders, a highly dense film with large crystalline grains was obtained. The CIGS film preserved its chemical composition of CuIn0.7Ga0.3Se2 after sintering as evidenced by Raman spectroscopy, EDS and SAED pattern of transmission electron microscopy. The film was also found suitable for a light absorbing layer of CIGS solar cells with its band gap energy of 1.14 eV evaluated by transmittance spectroscopy.

To describe the rationale, objectives, protocol, and preliminary results for a new prospective cohort study of cardiovascular disease (CVD) risk factors in South Korea.Study members were recruited from participants in routine health assessments at health promotion centres across South Korea. Established and emerging CVD risk factors were measured. Eighteen centres holding electronic health records agreed to linkage of participants' records to future health insurance claims for monitoring of disease events. The recruitment of 430,920 participants (266,782 men, 164,138 women), aged 30-74 years, provides broad geographical reach across South Korea.Risk factor prevalence was more favourable in women than men, and, in general, in the younger rather than older study members. There was also close similarity between the characteristics of the present sample and the Korean National Health and Nutrition Examination Survey. The expected associations between risk factors and both CVD and death were also apparent.Data from the present sample, based on data linkage, show close agreement with South Korea-wide surveys (for risk factor prevalence) and the extant literature (for risk factor associations). These findings gives confidence in future results anticipated from this cohort study of east Asians - a group that has been traditionally under-researched.

Relationship between Osteoporosis and Cardiovascular Risk Factors according to Sasang Constitution in Rural Wonju Cohort Hak-Soo Song, Jae-Wan Choi * , Jun-Sang Yu † , Jong-Ku Park ‡ Gamchodang Korean Medicine Clinic, * Yoonjewoo Korean Medicine Clinic, † Dept. of Sasang Constitutional Medicine, College of Korean Medicine, Sangji University, ‡ Dept. of Preventive Medicine, Wonju College of Medicine, Yonsei UniversityObjectivesThe purpose of this study was to investigate the relationship between osteoporosis and cardiovascular risk factorsaccording to Sasang constitution. Methods A total of 1773 participants, over 40 years old, were examined as part of a community-based cohort in Wonju city in Gangwon province of South Korea, from June 2006 to August 2009. We measured bone mineral density by Achilles ultrasonometer, serum levels of lipids, fasting blood sugar, insulin and other cardiovascular risk factorslike blood pressure and waist circumference. Constitution was verified by a Sasang constitution specialist using the results of PSSC(Phonetic System for Sasang Constitution), facial photos and a simplified Sasang constitutionalquestionnaire. Results The prevalence rate was 11.2% in total participants, and 10.6% in Soyangin, 10.4% in Taeeumin and 13.9% in Soeumin. In general characteristics, educational and economic property and exercise were concerned with osteoporosis.Systolic blood pressure, pulse rate and total cholesterol were significantly high in osteoporosis group. Age and menopause were the key risk factors for osteoporosis. There was a significantly high prevalence in Soeumin for osteoporosis in men alone. Low physical activity was a major risk factor for osteoporosis. Waist circumference and hip circumference had significantly high odds ratio and weight had significantly low odds ratio. By Sasang constitution, Soyangin has the negative correlation with free fatty acid, Taeeumin has the negative correlation with waist circumference, pulse rate, systolic blood pressure, total cholesterol and low density lipoprotein and Soeumin has the positive correlation with body fat amount. Conclusions Regimens on osteoporosis should be considered according to Sasang constitution. Cardiovascular diseases should be considered according to Sasang constitution. Soeumin should be cautious of osteoporosis and gain weights and reasonable amount of fat food. Soyangin had better do exercise lower body and eat little food containing triglyceride. Taeeumin had better lose weights and eat little cholesterol food.

Objectives : The objective of this study is to investigate various factors concerning Hwa-byung Methods : The research for various factors of Hwa-Byung was carried out for 686 female Participants. Hwa-Byung was diagnosed by Hwa-Byung Diagnostic Interview Schedule (HBDIS). Results : The rate of Past History about Chronic Bronchitis, Peptic Ulcer, Chronic Hepatitis/Hepatic Cirrhosis, Allergy, Arthritis, Hyperlipidemia is high in the Hwa-Byung group compared with the Control group. In the study of external environments, Hwa-Byung has tendency diagnosed in monthly income under 2,000,000 won, doing regular occupation, marriage, below graduation from high school. In the study of personal relationship, Hwa-Byung has tendency more influenced by negative influencing people than by positive influencing people. In the study of personal factors, Hwa-Byung has a short sleeping time, does not exercise regularly, feels more overburdened, and understimates their own condition to do easy tasks. Conclusions : According to the below results, in the study of Past History, the rate of Chronic Bronchitis, Peptic Ulcer, Chronic Hepatitis/Hepatic Cirrhosis, Allergy, Arthritis, and Hyperlipidemia is high in the Hwa-Byung group compared with the Control. Hwa-Byung has a tendency to be diagnosed by various factors such as the external environment, personal relationships, and personal factors.

Photocatalytic properties of TiO2 nanopowders has been received much attention due to their high potentials for environmental applications such as remediation of polluted environments. The TiO2 nanopowders doped with metal or non-metal elements have been synthesized by variety methods such as flame method, chemical vapor synthesis, sol-gel, ion implantation, which affect a doping behav- ior in different ways resulting in different surface characteristics, leading to different photocatalytic activity. In addition to an effect of synthesis methods, the photocatalytic activity of TiO2 nanopowders can be improved by subsequent heat-treatments. In this study, to obtain a highly efficient photocatalyst, we synthesized TiO2 nanopowders doped with tungsten by the chemical vapor synthesis method (CVS) and determined their physical properties and photocatalytic act ivity, together with subsequent post-treatment in the range of 300℃ to 700℃.

We developed a simple and effective method for the large scale formation of self-assembled Cu(In,Ga)Se 2 (CIGS) nanocrystals by ion beam irradiation. The compositional changes and morphological evolution were observed as a function of the irradiation time. As the ion irradiation time increased, the nano-dots were transformed into a nano-ridge structure due to the competition between sputtering and diffusion processes during irradiation. In terms of the stoichiometry of the CIGS nano-dots, an increase in the Cu content was observed while the Se content decreased. The PL peak of the nano-dots formed CIGS thin film exhibited a blue-shift. Uniformly formed crystalline CIGS nano-dots can be adopted to increase the p–n junction area and the size confinement effect between the CdS and CIGS film in solar cell systems. This simple method can be exploited for band-gap engineering and enhancing photovoltaic properties.

V-doped TiO2 nanopowders (Ti1-xVxO2) were manufactured by aerosol-assisted chemical vapor synthesis and were annealed for the observation of the oxidation of V and a phase transition. The nanopowder showed the red shift as well as a large visible absorption in UV–vis spectra due to many bridging Ti-O-V bonds. Copyright © 2012 John Wiley & Sons, Ltd.

We report a phenomenological study of Cu(In,Ga)Se2 (CIGS) dots and their morphological transition into nano-ridge shapes induced by application of a focused ion beam (IB) to CIGS film. Real-time observations of nano-structure evolution during IB irradiation were obtained by recording sequential images at various ion energies of 1 to 30 keV. We observed that as irradiation time increased, the dots became larger and developed elongated ridge structures under continuous sputtering. This transition process was induced by a combination of the Ostwald ripening processes and cluster diffusion. Compositional analysis revealed that the nano-dots changed from pristine CIGS to Cu-rich CIGS. The Ga content of the dots was also found to increase due to sputtered implantation, while levels of In and Se decreased. Copyright © 2012 John Wiley & Sons, Ltd.

During chemical vapor synthesis of TiO2 nanopowders, nitrogen atoms were doped into the crystal lattice of TiO2. The nitrogen atoms were predominantly incorporated substitutionally in the crystal lattice of TiO2 nanopowders up to the doping level of 1.25 mol% nitrogen, whereas they were in both interstitial and substitutional sites over about 1.43 mol% nitrogen. From the photocatalytic activity of nitrogen-doped TiO2 estimated by decomposition of methylene blue under visible light, it was found that the substitutional nitrogen anions appearing at the low level doping was beneficial to its photocatalytic activity, whereas the interstitial ones appearing at the high level doping over 1.25 mol% nitrogen were not. The improved photocatalytic activity due to the substitutionally doped nitrogen was attributed to band gap narrowing which was confirmed by the studies of XPS, near edge X-ray absorption fine structure, and UV–Vis absorption.

Background Leptin and adiponectin are adipokines, shown to have opposing functions for fat metabolism and development of metabolic syndrome. We determined if the ratio of serum leptin to adiponectin (L/A ratio) adjunctively contributes to the risk of metabolic syndrome beyond the homeostasis model assessment of insulin resistance (HOMA-IR). Methods This study included 1532 men and 1856 women, aged 40–70 y assessed in the Korean Genomic Rural Cohort Study from 2005 to 2008. The serum concentrations of adiponectin and leptin were measured by radioimmunoassay. Area under the receiver operating characteristic curve (AUROC) analyses were used to describe the ability of L/A ratio and HOMA-IR to differentiate between subjects with and without metabolic syndrome. Results There were no significant differences in the ability of L/A ratio and HOMA-IR to predict metabolic syndrome (AUROC of L/A ratio vs. HOMA-IR, 0.771 vs. 0.774, p = 0.8006 for men; 0.677 vs. 0.691, p = 0.3088 for women). There was a significant adjunctive contribution by the L/A ratio, beyond that of HOMA-IR, to the risk of metabolic syndrome in men ( p p = 0.025 with 0.017 increased AUROC). Conclusions The L/A ratio provides significant adjunctive information to the risk of metabolic syndrome beyond HOMA-IR alone. The L/A ratio could be a good surrogate marker to assess metabolic syndrome.

Objectives : This study was to research the relationship between Hwa-Byung and Framingham coronary risk score(FRS), cardiovascular disease. Methods : 649 people participated in the community based cohort study in Wonju City of South Korea from July 2nd to August 30th in 2006. Educated investigators checked up systolic & diastolic blood pressure and surveyed Hwa-Byung Diagnostic Interview Schedule(HBDIS), cohort questionnaire about gender, age, smoking, diabetes. Blood sample was collected from participants to analyze total cholesterol, HDL-cholesterol. FRS was calculated from collected data. 10-year prediction of coronary heart disease was determined from FRS by using score sheet that is estimated by Wilson et al. Collected data were analyzed by the chi-square test. Results : 1. Low risk number of people was 18(52.9%) in Hwa-Byung group, 263(42.8%) in non Hwa-Byung group. p-value was 0.472. Difference of the two group was invalid. 2. The number of people below or equal to average 10-year prediction of coronary heart disease as gnder & age, Hwa-Byung group was 19(55.9%), non Hwa-Byung group was 412(67.0%). p-value was 0.251. Difference of the two group was invalid. Conclusions : There was no correlationship Between Hwa-Byung and 10-year prediction of coronary heart disease.

Metabolic syndrome (MetS) is considered to be an insulin-resistance syndrome, but recent evidence suggests that MetS has multiple physiological origins which may be related to atherosclerosis. This study investigated clustering patterns of metabolic risk factors and its association with sub-clinical atherosclerosis.This study used factor analysis of 11 metabolic factors in 1374 individuals to define clustering patterns and determine their association with carotid intima-media thickness (CIMT). Eleven metabolic factors were used: body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), fasting blood insulin (FBI), serum triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), homeostasis model assessment-insulin resistance (HOMA-IR), high-sensitivity C-reactive protein (hsCRP) and adiponectin. Two regression analyses were done, the first using individual metabolic variables and the second using each factor from the factor analysis to evaluate their relationships with CIMT.Four clustering patterns, insulin-resistance factor (FBG, FBI, HOMA-IR), obesity-inflammatory factor (BMI, WC, hsCRP), blood pressure factor (SBP, DBP) and lipid metabolic factor (HDL-C, TG, adiponectin) were categorized. In a multivariate regression model after adjustment for age, sex, low-density lipoprotein cholesterol and smoking history (pack year), insulin resistance factor (B = 11.09, p = 0.026), obesity-inflammatory factor (B = 18.50, p0.001), blood pressure factor (B = 12.84, p = 0.010) and lipid metabolic factor (B = - 11.55, p = 0.023) were found to be significantly associated with CIMT.In conclusion, metabolic risk factors have four distinct clustering patterns that are independently associated with sub-clinical atherosclerosis.

Objectives : The purpose of this research is to investigate the corelationship between Hwa-Byung and type A behavior pattern (TABP), cardiovascular disease. Methods : 637 people participated in the community based cohort study in Wonju City of South Korea from July 2nd to August 30th in 2006. Educated investigators checked up EKG and surveyed Hwa-Byung Diagnostic Interview Schedule(HBDIS), Framingham Type A Pattern Score(FTA score). Collected data were analyzed by the chi-square test & t-test. Results : 1. TABP, Hwa-Byung group was 24(70.6%), non Hwa-Byung group was 288(27.8%) p-value was 0.016. Difference of the two group was valid. 2. FTA score, Hwa-Byung group was , non Hwa-Byung group was , p-value was 0.002. Difference of the two group was valid. Conclusions : TABP ratio, FTA score was high in Hwa-Byung group compared with non Hwa-Byung group.

Previous studies have reported an inconsistent relationship between alcohol consumption and bone health. A growing body of research has shown that chronic alcoholism leads to osteopenia and increased incidence of skeletal fractures, but some studies have concluded that alcohol consumption may be associated with higher bone mineral density in elderly populations. However, most studies showing a significant relationship between alcohol consumption and bone status have been in Western countries; and subjects have usually been postmenopausal women. The purpose of the present study was to investigate the association of alcohol consumption with bone strength in Korean adults. Data were from the Korean Genomic Rural Cohort Study, which is an ongoing population-based study of adults aged 40 to 70 years from 5 regions. A total of 7713 participants (3368 men, 4345 women) were surveyed about their annual consumption of alcohol such as soju, beer, makkolli, wine, and whisky. Bone strength was measured by stiffness index using the calcaneal quantitative ultrasound method. Overall, the annual age-specific decrease rate in the stiffness index of women was 2.7 times higher than that of men (0.463% for women, 0.169% for men).After adjustment for eligible covariates, the association between alcohol consumption and risk of reduced bone strength showed a J-shaped curve for both men and women. Compared with nondrinkers, the relative risk of reduced bone strength was 0.52 (95% confidence interval, 0.33-0.83) in men who drank 4 to 5 cups of soju for an amount of 29.626 to 49.375 g of alcohol per day and 0.61 (95% confidence interval, 0.38-0.86) in men who drank 6 to 7 cups of soju for an amount of 49.376 to 69.125 g of alcohol per day. We found no significant relationship between alcohol consumption and bone strength in any other group of men. For women, results suggested that the risk of reduced bone strength was lower in the moderate-consumption group; but no significant relationship was found between alcohol consumption at any level and bone strength. Among Korean adults, alcohol consumption has a J-shaped relationship with risk of reduced bone strength.

Growing body of evidence suggests an association between circulating adiponectin and the development of atherosclerosis. However most of these studies have been performed with healthy subjects with relatively small sample size or patients with preexisting cardiovascular diseases. The results obtained are inconstant for an independent association between adiponectin and subclinical atherosclerosis. We aimed to evaluate the association between circulating adiponectin and carotid intima media thickness (CIMT) in a large sample of individuals from the community. We performed a non-diabetic community based cohort study conducted on a healthy Korean adults (age>40 years) population. The serum adiponectin concentrations were measured by a radioimmunoassay. The mean adiponectin level was significantly lower in subjects with high CIMT defined by >0.9 mm than those with low CIMT (9.18 vs. 10.44 g/mL, P=0.03). The adiponectin level was correlated negatively with waist circumference (r=−0.27), body mass index (r=−0.21), systolic blood pressure (r=−0.11), diastolic blood pressure (r=−0.10), triglyceride (r=−0.30), LDL-cholesterol (r=−0.02), glucose (r=−0.16), insulin (r=−0.17), homeostasis assessment-insulin resistance (r=−0.23) and C-reactive protein (r=−0.11), and correlated positively with HDL cholesterol (r=0.30) (all P

Carotid intima-media thickness (CIMT) is considered as a surrogate marker for cardiovascular disease (CVD). We determined the normative value of CIMT and correlates of CVD risk factors and Framingham risk score (FRS) in Korean rural middle-aged population. We measured CIMT with a B-mode ultrasonography in 1,759 subjects, aged 40 to 70 yr, in a population-based cohort in Korea. A healthy reference sample (n = 433) without CVD, normal weight and normal metabolic parameters was selected to establish normative CIMT values. Correlates between CIMT and conventional CVD risk factors were assessed in the entire population. Mean values of CIMT (in mm) for healthy reference sample aged 40-49, 50-59, and 60-70 yr were 0.55, 0.59, and 0.66 for men and 0.48, 0.55, and 0.63 for women, respectively. In multivariate regression analysis, CIMT was correlated with older age, higher BMI, male gender, higher LDL-cholesterol level and history of diabetes mellitus. The mean CIMT was also correlated with FRS in both gender (r(2) = 0.043, P < 0.01 for men; r(2) = 0.142, P < 0.01 for women). We identified normative value of CIMT for the healthy Korean rural middle-aged population. The CIMT is associated with age, obesity, gender, LDL-cholesterol, diabetes mellitus and FRS.

Background Albuminuria is a surrogate marker of endothelial dysfunction and a predictor of cardiovascular events. Data are limited with regard to the relationship between albuminuria and subclinical atherosclerosis in a community-based cohort. We determined the association between albuminuria measured by the urine albumin creatinine ratio (UACR) and carotid intima media thickness (CIMT) in a Korean rural population. Methods We enrolled 1,369 healthy subjects older than 40 years (857 males and 518 females) with normal renal function and measured the CIMT. We excluded subjects with overt proteinuria (> 300 mg/day) or with treatment of diabetes mellitus, hypertension, dyslipidemia, and any cardiovascular disease. The subjects were stratified into the quartile value of the UACR (lowest quartile: UACR < 4.8 and highest quartile: UACR > 17.7). And we evaluate the relationship between UACR and CIMT by linear regression and logistic regression analysis. Results Increasing quartile of the UACR had a stepwise increase in body mass index, blood pressure, cholesterol profile [low density lipoprotein (LDL)-cholesterol and triglyceride], glucose, homeostratic model assessment of insulin resistance (HOMA-IR), and C-reactive protein (all p values < 0.001). Maximal CIMT from the 1st to the 4th quartile values of the UACR were 0.74 ± 0.17, 0.77 ± 0.18, 0.78 ± 0.18, and 0.82 ± 0.21 mm, respectively (p < 0.001). In a multivariate regression model adjusted for age, sex, systolic blood pressure, triglyceride, LDL-cholesterol, fasting blood sugar, waist circumference, adiponectin, HOMA-IR, high sensitive C-reactive protein, smoking, UACR showed a significant association with maximal CIMT (B = 0.014, R2 = 0.145, p = 0.002). Conclusion Albuminuria measured by the UACR was significantly associated with both CIMT and traditional risk factors of atherosclerosis except for smoking in healthy Koreans.

This paper describes a pH-responsive multilayer film composed of two layered components, namely poly(allylamine hydrochloride) (PAH) and a copolymer of acrylic acid and [1,3]oxazine-modified acrylate (POA). The oxazine ring is an acidochromic chromophore and opens to form either cationic 3H-indolium or anionic hemiaminal in a pH-dependent manner. This structural transition was used to generate a net positive or negative charge on the membrane for selective ion permeation. Interestingly, the reversible oxazine ring opening and closing proceeded smoothly without significant steric hindrance in the multilayer film comprising 10 PAH/POA bilayers. The pH-responsive permselectivity for cationic and anionic probe molecules was demonstrated using a POA monolayer film adsorbed electrostatically onto an amino-functionalized ITO electrode. The origin of the excellent ion-transport selectivity in the 1 nm ultrathin POA membrane is discussed in terms of alternating charges of the aromatic amphoteric group, oxazine, in the polyeletrolyte membrane.

The Korean Society for the Study of Obesity (KSSO) has defined the waist circumference cutoff value of central obesity as 90 cm for men and 85 cm for women. The purpose of this investigation was to determine the corresponding waist circumference values. A total of 3,508 persons in the Korean Rural Genomic Cohort Study were enrolled in this survey. Receiver operating characteristic (ROC) curve analysis was used to find appropriate waist circumference cutoff values in relation to insulin resistance determined by homeostasis model assessment for insulin resistance (HOMA-IR), body mass index (BMI), and components of metabolic syndrome. The optimal waist circumference cutoff values were 87 cm for men and 83 cm for women by ROC analysis to HOMA-IR and 86 cm for men and 83 cm for women by ROC analysis to value with more than two components of metaobolic syndrome. By using a BMI > or =25 kg/m(2), 86 cm for men and 82 cm for women were optimal waist circumference cutoff values. In this study, we suggest that the most reasonable waist circumference cutoff values are 86-87 cm for men and 82-83 cm for women.

The objective of this study was to assess relationships between adiponectin and the status of glucose metabolism and to investigate whether low adiponectin levels were independently associated with the risk of impaired glucose metabolism and type 2 diabetes in Korean population. A total of 3,508 participants (mean age 56.3±8.0 years; BMI 24.7±3.2 kg/ m2; 41.0% male) were enrolled. Participants with normal glucose metabolism (NGM), impaired glucose metabolism (IGM), and type 2 diabetes were 58.0%, 28.9%, and 13.1%. Adiponectin levels in both men and women were significantly lower in participants with IGM and type 2 diabetes than participants with NGM. Low adiponectin levels in both men and women were strongly associated with the risk of IGM and type 2 diabetes in large population-based cohort of rural adult Koreans.

Toward the realization of nanoscale device control, we report a novel method for photoregulation of ion flux through a polyelectrolyte multilayer membrane by chromophore orientation that is adjusted either by illumination at normal incidence or by slantwise irradiation at an angle of 10 degrees with respect to the surface. Our results indicate that the chromophore reorientation caused by the slantwise irradiation controls the effective pore size and, consequently, the transport behavior on the nanoscale. The slantwise illumination, which includes six EZE photoisomerization cycles generated by alternately irradiating with ultraviolet (lambda = 360 nm) and visible (lambda = 450 nm) light, reversibly switches the orientation of E-azobenzene in the membrane between 53 +/- 2 degrees (high tilt) and 17 +/- 5 degrees (low tilt) with respect to the surface. The novel feature of this light-gated valve system is its extremely long-lived open-switch state; this behavior stands in contrast to that of other systems based on labile photoisomers, which tend to instantly return to the thermodynamically stable state.

Anatase-type TiO2 nanopowders less than 10 nm in average diameter were synthesized by a chemical vapor synthesis method. The TiO2 nanopowders showed very poor photocatalytic properties, in spite of their large surface area. With subsequent heat treatment of the TiO2 powders, their photocatalytic properties determined by measuring the degradation of 2-propanol were improved at temperatures up to 600 °C and then diminished along with formation of a rutile phase. This improvement in the photocatalytic properties of TiO2 nanopowders was attributed to both a morphology change and a change in the electronic surface characteristics of TiO2 particles during heat treatment.

A flame aerosol method has been employed to prepare spherical TiO2 nano-particle photocatalysts with controlled anatase/rutile phase ratios without calcination at higher temperatures. This method was found to have important advantages since the main factors in achieving high photocatalytic activity such as the particle size, crystallinity and the anatase/rutile phase ratios could be easily controlled. In particular, the incorporation of small amounts of bimetals, such as Fe and Zn, were found to initiate the formation of well-crystalline, small and uniform spherical nano-size particles with a well-defined anatase/rutile phase ratio of around 60/40, similar to P-25 TiO2. This suppressed the recombination of the photoformed charge carriers leading to a significant increase in the photocatalytic reactivity of the TiO2 nano-particles. The incorporation of very small amounts of mono-metals, such as Fe, Cr and Zn (around 1 at.%), within the TiO2 nano-particles led to a slight increase in the photocatalytic activity of the TiO2 nano-particle photocatalysts for the complete oxidation of 2-propanol dissolved in water into CO2 and H2O as compared with the unincorporated pure TiO2. The incorporation of bimetals of Fe and Zn within TiO2 (Fe/Zn–TiO2) nano-particles, on the other hand, led to a remarkable enhancement in the photocatalytic activity as compared with the unincorporated and mono-metal incorporated TiO2.

Objectives: The challenge of an increasing elderly population has coupled with everpresent social concerns in Korea. A major problem in health center for the frail older people is that medical, healthcare, and welfare services are often fragmented in terms of providers and settings without appropriate coordination. The purpose of this study was to investigate the need of health center-based integrated healthcare services and its related factors for the elderly. Methods: A total of 110 elderly people who had visited at a county Health Center were interviewed using a self-administered questionnaire from November to December, 2005. The questionnaire consists of five domains according to the Program of All-inclusive Care for the Elderly. Results: Respondents had high need (total mean score with the 5-point Likert-type sacle: 3.67) of health center-based integrated healthcare services including home visiting service (mean: 4.08), chronic disease care service (mean: 4.06), and transportation service (mean 4.05). According to the results of hierarchical multiple regression analysis, among three regression models the magnititude of the variance of full model that is explained by the need of welfare-domain service was significantly larger than two reduced model. Income was a significant variable in increasing the need of health care and welfare services. Conclusions: This study suggests that the health center-based integrated healthcare services for the elderly must be continuously developed and provided for the health promotion and improved the quality of life of the elderly who live in rural area in Korea.

In the fabrication of dye-sensitized solar cells (DSSCs), carbon counter electrode has been tested for replacing the platinum counter electrode which has two drawbacks: limited surface area and high material cost. Poor mechanical stability of carbon layer due to weak bonding strength to electrically conductive TCO (transparent conducting oxide) glass substrate is a crucial barrier for practical application of carbon counter electrode. In the present study a carbon counter electrode with high conversion efficiency, comparable to Pt counter electrode, could be fabricated by adaption of a bonding layer between particulate carbon material and TCO substrate.

Bimetal incorporated TiO2 photocatalysts (FeZn–TiO2) prepared by a flame method showed high photocatalytic activity for the degradation of 2-propanol dissolved in water as compared with mono-metal incorporated or unincorporated TiO2. By using this flame method, parameters such as uniform particle size, crystallinity as well as the anatase and rutile phase ratio (anatase/rutile) could be controlled without calcination of the catalysts at high temperatures, the parameters being important to achieve a high photocatalytic activity. The presence of a small amount of bimetals such as Fe and Zn plays a vital role as a catalyst in the formation of highly crystalline, small and uniform size particles with defined anatase/rutile phase ratio of around 60/40, this being similar to that of P-25 which is well known as a highly active photocatalyst.

To manufacture a flange for a compressor with a relief groove by using powder metallurgy in order to prevent deformation to the compressor in operation, powder material for the flange is charged into a mold; an ablative member having a melting point lower than that of the powder material is positioned at a place where a relief groove is to be formed; the flange is formed by compressing the powder material and the ablative member; and the formed flange is sintered at a temperature between the melting point of the powder material and the ablative member so as to melt and remove the ablative member. It made according to the new method has more excellent strength and airtight property than the conventional one. It is analyzed that the ablative member is melted and penetrated into the flange structure during the sintering process, which results in improvement of the airtight property and increase of the strength.

TiO2 nanoparticle was synthesized by the flame method using a metal organic precursor of titanium tetraisopropoxide (TTIP, Ti(OC3H7)4), which was controlled by varying the ratio and flow rate of gas mixtures consisting of oxygen (oxidizer), methane (fuel) and nitrogen (carrier gas). The morphology and the size distribution of nanoparticles were observed with TEM and FESEM, and the phase evolution was analyzed by XRD measurement using a monochromator. The crystalline phases of TiO2 nanoparticle depended strongly on the temperature distribution in the flame, whereas the morphology was not sensitive. During the flame synthesis of TiO2 nanoparticle, anatase TiO2 nanoparticle was predominantly synthesized at the high flame temperature and rapid flame cooling condition. The low flame temperature and long flame length enabled to form almost rutile TiO2 nanoparticle (>95%). The anatase nanoparticle was formed by a homogeneous nucleation and has finally kept the anatase phase without the phase transformation any more in the flame. However, the rutile TiO2 nanoparticle was not formed directly and homogeneously in flame, and was manufactured by the phase transformation such as amorphousanataserutile. It was proved that the rutile phase was nucleated heterogeneously from the amorphous or anatase particles.

The spherical anatase TiO2 nanoparticle of 50 nm in diameter was manufactured by flame method and was subsequently heat-treated to investigate the transformation behavior from anatase to rutile using TEM observation. The anatase particle was facetted at the free surface and a neck formed between the anatase particles prior to the phase transformation. This resulted in the severe lattice distortion at the region of the interface. Unfortunately, we could not find the rutile grain nucleated in the anatase particle due to very fast grain growth. All the phase boundaries observed in HRTEM images existed in the contact between anatase and rutile particles. The nucleation of rutile phase in anatase particle was suppressed at the low heat-treated temperature but the grain growth of rutile particles after the phase transformation grew very fast by the sweeping phenomena of grain boundary. It leaded to the microstructure without the rutile phase traped in anatase particle.