Capillary force lithography with impermeable molds

Capillary force lithography (CFL) with impermeable mold is presented. For the CFL to be operative over large area, either the mold or the substrate has to be flexible. With a silicon wafer mold and a flexible substrate, a repeated line and space pattern with a spacing of 30 nm is shown to be well patterned. With a flexible mold and a hard substrate, a similar pattern with a spacing of 60 nm is demonstrated by CFL. The flexibility is needed for the intimate contact that is required between the mold and the substrate for the capillarity to take hold over large area. The forte of CFL with impermeable mold lies in the fact that the driving force for the patterning, which is capillary force, increases with decreasing pattern size.This work was supported by the Korea Foundation Grant funded by MOEHRD (KRF-2005-041-D00250)

Classification of rice (oryza sativa l. japonica nipponbare) immunophilins (fkbps, cyps) and expression patterns under water stress

<p>Abstract</p> <p>Background</p> <p>FK506 binding proteins (FKBPs) and cyclophilins (CYPs) are abundant and ubiquitous proteins belonging to the peptidyl-prolyl <it>cis/trans </it>isomerase (PPIase) superfamily, which regulate much of metabolism through a chaperone or an isomerization of proline residues during protein folding. They are collectively referred to as immunophilin (IMM), being present in almost all cellular organs. In particular, a number of IMMs relate to environmental stresses.</p> <p>Results</p> <p>FKBP and CYP proteins in rice (<it>Oryza sativa </it>cv. Japonica) were identified and classified, and given the appropriate name for each IMM, considering the ortholog-relation with <it>Arabidopsis </it>and <it>Chlamydomonas </it>or molecular weight of the proteins. 29 FKBP and 27 CYP genes can putatively be identified in rice; among them, a number of genes can be putatively classified as orthologs of <it>Arabidopsis </it>IMMs. However, some genes were novel, did not match with those of <it>Arabidopsis </it>and <it>Chlamydomonas</it>, and several genes were paralogs by genetic duplication. Among 56 IMMs in rice, a significant number are regulated by salt and/or desiccation stress. In addition, their expression levels responding to the water-stress have been analyzed in different tissues, and some subcellular IMMs located by means of tagging with GFP protein.</p> <p>Conclusion</p> <p>Like other green photosynthetic organisms such as <it>Arabidopsis </it>(23 FKBPs and 29 CYPs) and <it>Chlamydomonas </it>(23 FKBs and 26 CYNs), rice has the highest number of IMM genes among organisms reported so far, suggesting that the numbers relate closely to photosynthesis. Classification of the putative FKBPs and CYPs in rice provides the information about their evolutional/functional significance when comparisons are drawn with the relatively well studied genera, <it>Arabidopsis </it>and <it>Chlamydomonas</it>. In addition, many of the genes upregulated by water stress offer the possibility of manipulating the stress responses in rice.</p

Consecutive Junction-Induced Efficient Charge Separation Mechanisms for High-Performance MoS2/Quantum Dot Phototransistors.

Phototransistors that are based on a hybrid vertical heterojunction structure of two-dimensional (2D)/quantum dots (QDs) have recently attracted attention as a promising device architecture for enhancing the quantum efficiency of photodetectors. However, to optimize the device structure to allow for more efficient charge separation and transfer to the electrodes, a better understanding of the photophysical mechanisms that take place in these architectures is required. Here, we employ a novel concept involving the modulation of the built-in potential within the QD layers for creating a new hybrid MoS2/PbS QDs phototransistor with consecutive type II junctions. The effects of the built-in potential across the depletion region near the type II junction interface in the QD layers are found to improve the photoresponse as well as decrease the response times to 950 μs, which is the faster response time (by orders of magnitude) than that recorded for previously reported 2D/QD phototransistors. Also, by implementing an electric-field modulation of the MoS2 channel, our experimental results reveal that the detectivity can be as large as 1 × 1011 jones. This work demonstrates an important pathway toward designing hybrid phototransistors and mixed-dimensional van der Waals heterostructures.The research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP/2007−2013)/ERC Grant Agreement no. 340538. This work was also supported by the National Research Foundation of Korea (NRF) (2015M2A2A6A02045252) and Samsung Global Research Outreach (Samsung GRO) program. In addition, S.M.M. would like to thank The Royal Society for financial support

Strain-Mediated Interlayer Coupling Effects on the Excitonic Behaviors in an Epitaxially Grown MoS2/WS2 van der Waals Heterobilayer.

van der Waals heterostructures composed of two different monolayer crystals have recently attracted attention as a powerful and versatile platform for studying fundamental physics, as well as having great potential in future functional devices because of the diversity in the band alignments and the unique interlayer coupling that occurs at the heterojunction interface. However, despite these attractive features, a fundamental understanding of the underlying physics accounting for the effect of interlayer coupling on the interactions between electrons, photons, and phonons in the stacked heterobilayer is still lacking. Here, we demonstrate a detailed analysis of the strain-dependent excitonic behavior of an epitaxially grown MoS2/WS2 vertical heterostructure under uniaxial tensile and compressive strain that enables the interlayer interactions to be modulated along with the electronic band structure. We find that the strain-modulated interlayer coupling directly affects the characteristic combined vibrational and excitonic properties of each monolayer in the heterobilayer. It is further revealed that the relative photoluminescence intensity ratio of WS2 to MoS2 in our heterobilayer increases monotonically with tensile strain and decreases with compressive strain. We attribute the strain-dependent emission behavior of the heterobilayer to the modulation of the band structure for each monolayer, which is dictated by the alterations in the band gap transitions. These findings present an important pathway toward designing heterostructures and flexible devices

Multimorbidity and Health-Related Quality of Life in Korean Older Adults: A Mediation Analysis on Handgrip Strength

Background: The influence of handgrip strength on the relationship of multimorbidity with health-related quality of life (HRQoL) is unknown in geriatric populations. The current study investigated whether or not handgrip strength mediates the association between multimorbidity and HRQoL in a representative sample of Korean adults (3139 men/3753 women) aged 65 years and older. Methods: The data obtained from the 2014–2019 Korea National Health and Nutrition Examination Survey (KNHNES) were used in the current study. The EuroQoL group was used to assess HRQoL. Multimorbidity was defined as co-existence of more than one of the 26 diagnosed diseases specified in the KNHNES. A digital hand dynamometer was used to measure handgrip strength. The covariates included in this study were age, gender, parameters of body fatness, socio-demographics, and parameters of health behaviors. Results: Analysis of variance showed that HRQoL was inversely associated with number of chronic conditions and positively with relative handgrip strength. Particularly, a mediation analysis using the PROCESS macro in SPSS-PC showed that relative handgrip strength partially mediates the influence of multimorbidity on HRQoL. Bootstrapping showed that the indirect effect of comorbidity on HRQoL via relative handgrip strength was significant (p < 0.001) even after adjustments for all the covariates, explaining 8.1% the total effect. Conclusions: The findings of the study emphasize the importance of health-related physical fitness while managing and/or treating multiple chronic conditions for better HRQoL in geriatric populations

Unintentional weight loss as a predictor of all-cause and cardiovascular disease mortality in older Korean men

Background and objective: Little is known regarding the prognostic role of unintentional weight loss (UWL) in mortality risk among older Korean men. This study examined the associations of UWL and unhealthy behaviors with all-cause and cardiovascular disease (CVD) mortality in Korean men aged 60 years and older. Material and Methods: Data (n = 2,309) obtained from the Korean longitudinal study of aging were analyzed. Exposures were UWL, smoking, alcohol abuse, underweight/obesity, and physical inactivity. Primary outcomes were all-cause mortality and CVD mortality. Covariates included parameters of sociodemographics and health conditions. Results: Individuals with three or more risk factors had significantly higher risks of all-cause mortality (hazard ratio [HR] = 1.536, 95% confidence interval [CI] = 1.084~2.175, P = 0.016) and CVD mortality (HR = 2.925, 95% CI = 1.386~6.174, P = 0.005) even after adjustments for parameters of sociodemographics, health conditions, and UWL compared to individuals with zero risk factors (HR = 1). Additionally, individuals with UWL had a significantly higher risk of all-cause mortality (HR = 1.307, 95% CI = 1.052~1.623, P = 0.016) even after adjustments for the covariates and lifestyle risk factors compared to individuals with normal weight (HR = 1). Conclusion: The current findings show that exposure to three or more lifestyle risk factors is an independent predictor of all-cause mortality and CVD mortality, and UWL was a predictor of all-cause mortality in older Korean men

The Relationship between Depressive Symptoms and Modifiable Lifestyle Risk Factors in Office Workers

Background : This study investigated the relationship between depressive symptoms and physical fitness, obesity indices, and vitamin D status in office workers. Methods : The subjects were 514 adults with more 30 years of experience as office workers in the city of Seoul. Lifestyle risk factors, obesity indices, physical fitness, and serum vitamin D levels were assessed with a standardized protocol. The Beck Depression Inventory (BDI) was used to assess depression status. Vitamin D status was assessed by measuring serum 25-hydroxyvitamin D concentrations. Based on the BDI scores, participants were classified into no depression (ND, BDI ≤9), mild depression (MiD, 10≤BDI≤15), and moderate depression (MoD, 16≤BDI≤23) groups. Results : Compared with the high cardiorespriatory fitness group, the low cardiorespiratory fitness (men OR=2.618, women OR=1.596) an middle cardiorespiratory fitness group (men OR=1.256, women OR=1.110) had significantly higher odds ratio for having depressive symptoms, even after adjustment for age, hypertension, diabetes, hyperlipidemia, cardiovascular disease, alcohol intake, smoking, body mass index (BMI), percent body fat (%BF), and waist circumference (WC). Compared with the insufficient or deficient vitamin D group, the sufficient vitamin D group had significantly lower odds ratios for having depressive symptoms (men OR=0.121, women OR=0.114), even after adjustment for age, hypertension, diabetes, hyperlipidemia, cardiovascular disease, alcohol intake, smoking, BMI, %BF, and WC. Conclusion : Vitamin D supplementation and outdoor activities should be key components of a lifestyle intervention against office workers’ depression

The Relationship of Lifestyle Risk Factors and Depression in Korean Adults: A Moderating Effect of Overall Nutritional Adequacy

Background: Little is known regarding the role of nutrition in determining the associations between lifestyle risk factors and depression. Objectives: This study examined whether or not nutritional adequacy modulates the relationship between depression and lifestyle risk factors in Korean adults aged 18-65 years (n = 7446). Methods: Data were obtained from the 2016 and 2018 Korea National Health and Examination Survey. Depression, smoking, at-risk alcohol consumption, physical inactivity, sleep deprivation, and mean adequacy ratio (MAR) were assessed. Results: Individuals with two (OR = 1.960, p &lt; 0.001), three (OR = 4.237, p &lt; 0.001), or four (OR = 5.312, p &lt; 0.001) risk factors had a significantly higher risk of depression compared to individuals with one or zero risk factor. In contrast, individuals with moderate MAR (OR = 0.607, p &lt; 0.001) and high (OR = 0.698, p &lt; 0.001) MAR had a lower depression risk compared to individuals with low MAR. Moderation analysis showed a moderating effect of MAR (coefficient = −0.220, p = 0.007) on the relationship between risk factors and depression. Conclusions: The current findings suggest that overall nutritional adequacy plays a modulating role in determining the relationship between depression and lifestyle risk factors in Korean adults

Insulin Resistance and Its Association with Metabolic Syndrome in Korean Children

Background. This study investigated the association between insulin resistance (IR) and metabolic syndrome (MetS) in children. Methods. A cross-sectional study involving 1036 healthy children aged between 7 and 13 years was conducted. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated as an index of IR. Participants were classified according to the HOMA-IR quartiles. Results. Incremental, linear trends were found in age (p<0.001), body mass index (BMI) (p<0.001), body fat (p<0.001), waist circumference (p<0.001), resting blood pressures (BP) (p<0.001), triglycerides (TG) (p<0.001), total cholesterol (TC) (p<0.001), high density lipoprotein-cholesterol (HDL-C) (p<0.001), FBG (p<0.001), and insulin (<0.001) according to incremental HOMA-IR categories (from the 1st to 4th quartile). Compared with children in the 1st HOMA-IR quartile, children in the 4th HOMA-IR quartile had significantly higher odd ratios (ORs) of abnormalities in systolic (p=0.051) and diastolic BP (p=0.005), FBG (p<0.001), TG (p<0.001), TC (p=0.016), and HDL-C (p=0.006) even after adjustments for age, gender, BMI, and body fat percentage. Children in the 3rd HOMA-IR quartile had significant abnormalities in FBG (p<0.001), TG (p=0.001), and HDL-C (p=0.010) even after adjustments for the covariates. Conclusion. The current findings suggest that IR is significantly associated with the clustering of MetS risk factors in children in Korea