Prefabricated Steel-Reinforced Concrete Composite Column

In conventional concrete-encased steel composite columns, a steel section is placed at the center of the cross section. Thus, the contribution of the steel section to the overall flexural capacity of the column could be limited. For better efficiency and economy, particularly under biaxial moment, the steel section needs to be placed at the corners, rather than at the center of the cross section. Recently, a prefabricated steel-reinforced concrete column has been developed to utilize the advantages of the reinforced concrete column and the steel-concrete composite column. In the composite column, four steel angles are placed at the corners of the cross section, and transverse bars and plates are used to connect the angles by welding or bolting. The composite column has been widely applied to industrial buildings that require large sized columns and fast construction. In this chapter, the newly developed composite column is introduced, and basic mechanism, structural performance, and field application case are discussed

Decoding Single Molecule Time Traces with Dynamic Disorder

Single molecule time trajectories of biomolecules provide glimpses into complex folding landscapes that are difficult to visualize using conventional ensemble measurements. Recent experiments and theoretical analyses have highlighted dynamic disorder in certain classes of biomolecules, whose dynamic pattern of conformational transitions is affected by slower transition dynamics of internal state hidden in a low dimensional projection. A systematic means to analyze such data is, however, currently not well developed. Here we report a new algorithm - Variational Bayes-double chain Markov model (VB-DCMM) - to analyze single molecule time trajectories that display dynamic disorder. The proposed analysis employing VB-DCMM allows us to detect the presence of dynamic disorder, if any, in each trajectory, identify the number of internal states, and estimate transition rates between the internal states as well as the rates of conformational transition within each internal state. Applying VB-DCMM algorithm to single molecule FRET data of H-DNA in 100 mM-Na$^+$ solution, followed by data clustering, we show that at least 6 kinetic paths linking 4 distinct internal states are required to correctly interpret the duplex-triplex transitions of H-DNA

MixRL: Data Mixing Augmentation for Regression using Reinforcement Learning

Data augmentation is becoming essential for improving regression accuracy in critical applications including manufacturing and finance. Existing techniques for data augmentation largely focus on classification tasks and do not readily apply to regression tasks. In particular, the recent Mixup techniques for classification rely on the key assumption that linearity holds among training examples, which is reasonable if the label space is discrete, but has limitations when the label space is continuous as in regression. We show that mixing examples that either have a large data or label distance may have an increasingly-negative effect on model performance. Hence, we use the stricter assumption that linearity only holds within certain data or label distances for regression where the degree may vary by each example. We then propose MixRL, a data augmentation meta learning framework for regression that learns for each example how many nearest neighbors it should be mixed with for the best model performance using a small validation set. MixRL achieves these objectives using Monte Carlo policy gradient reinforcement learning. Our experiments conducted both on synthetic and real datasets show that MixRL significantly outperforms state-of-the-art data augmentation baselines. MixRL can also be integrated with other classification Mixup techniques for better results.Comment: 15 pages, 9 figures, 7 table

Time-resolved imaging of non-diffusive carrier transport in long-lifetime halide perovskite thin films

Owing to their exceptional semiconducting properties, hybrid inorganic-organic perovskites show great promise as photovoltaic absorbers. In these materials, long-range diffusion of charge carriers allows for most of the photogenerated carriers to contribute to the photovoltaic efficiency. Here, time-resolved photoluminescence (PL) microscopy is used to directly probe ambipolar carrier diffusion and recombination kinetics in hybrid perovskites. This technique is applied to thin films of methylammonium lead tri-iodide MAPbI$_3$ obtained with two different fabrication routes, methylammonium lead tribromide (MAPbBr$_3$), and an alloy of formamidinium lead tri-iodide (FAPbI$_3$) and methylammonium lead bromide FA$_{0.85}$MA$_{0.15}$Pb(I$_{0.85}$Br_${0.15}$)$_3$. Average diffusion coefficients in the films leading to the highest device efficiencies and longest lifetimes, i.e., in FA$_{0.85}$MA$_{0.15}$Pb(I$_{0.85}$Br$_{0.15}$)$_3$ and acetonitrile-processed MAPbI$_3$, are found to be several orders of magnitude lower than in the other films. Further examination of the time-dependence shows strong evidence for non-diffusive transport. In particular, acetonitrile-processed MAPbI$_3$ shows distinct diffusion regimes on short and long timescales with an effective diffusion constant varying over 2 orders of magnitude. Our results also highlight the fact that increases in carrier lifetime in this class of materials are not necessarily concomitant with increased diffusion lengths and that the PL quantum efficiency under solar cell operating conditions is a greater indication of material, and ultimately device, quality

Elastomeric membrane valves in a disc

We present elastomeric membrane valves integrated into a centrifugal microfluidic platform for precise control of fluid on a disc. The amount of the fluid passing through the valves, which depends on the rotating speed of the disc and the membrane thickness, has been characterized, and could be precisely controlled by tuning the disc motion.close131

?????? ????????? ????????? ?????? ?????? ?????? ??????

Department of Biological SciencesThe type 2 diabetes mellitus (T2DM) was one of the most significant public health challenges in 21th century. The T2DM in most instances are characterized by alteration in insulin secretion and insulin sensitivity or a combination of both. For the last decade, a lot of attention has been focused on insulin resistance as a critical cause on development of T2DM. However, after many years from diagnosis of the T2DM, individuals with the disease were largely accompanied by continuous decline in ??-cell function. Indeed, pancreatic ??-cells have vital role in pathogenesis of T2DM and understanding ??-cells physiology can reliably alleviates the disease. Thus, in the future, cure for T2DM will require genetic or pharmacological approaches to be beneficial to ??-cells. Here, I focused the phospholipase C?? (PLC??) for elucidation of molecular aetiology for T2DM and zafirlukast drug for effective interventions to combat T2DM epidemic. In the first chapter of this dissertation, I reviewed overall regulatory mechanism of insulin secretion, especially focused on PLC??s and high-throughput tools for discovering regulator of insulin secretion. In the second chapter, I described the PLC??1-mediated insulin secretion. Phospholipase C?? (PLC??) exerts biological influences through G protein-coupled receptors (GPCRs). GPCRs are involved in regulating glucose-stimulated insulin secretion (GSIS). Previous studies have suggested that PLC??s might play an important role in pancreatic ??-cells. However, due to a lack of the specific inhibitors of PLC?? isozymes and appropriate genetic models, the in vivo function of specific PLC?? isozymes in pancreatic ??-cells and their physiological relevance in the regulation of insulin secretion has not been studied so far. The present study showed that PLC??1 was crucial for ??-cell function by generation of each PLC?? conditional knockout mice. Mice lacking PLC??1 in ??-cells exhibited a marked defect in GSIS, leading to glucose intolerance. In ex vivo studies, the secreted insulin level and Ca2+ response in Plcb1f/f; Pdx1-CreERt2 islets was lower than those in the Plcb1f/f islets under the high glucose condition. PLC??1 led to potentiate insulin secretion via stimulation of particular Gq proteincoupled receptors. Plcb1f/f; Pdx1-CreERt2 mice fed a high fat diet developed more severe glucose intolerance due to a defect in insulin secretion. In the last chapter, I reported a novel function of zafirlukast as insulin secretagogue. The zafirlukast has been reported to be anti-inflammatory and widely used to alleviate the symptoms of asthma. However, its influence on insulin secretion in pancreatic ??-cells has not been investigated. Herein, we examined the effects of zafirlukast on insulin secretion and the potential underlying mechanisms. Among the cysteinyl leukotriene receptor 1 antagonists, zafirlukast, pranlukast, and montelukast, only zafirlukast enhanced insulin secretion in a concentration-dependent manner in both low and high glucose conditions and elevated the level of [Ca2+]i, further activating Ca2+/calmodulindependent protein kinase II (CaMKII), protein kinase B (AKT), and extracellular signal-regulated kinase (ERK) signaling. These effects were nearly abolished by the L-type Ca2+ channel antagonist nifedipine, while treatment with thapsigargin, a sarco/endoplasmic reticulum Ca2+ ATPase inhibitor, did not have the same effect, suggesting that zafirlukast primarily induces the entry of extracellular Ca2+ rather than intracellular Ca2+ from the endoplasmic reticulum. Zafirlukast treatment resulting in a significant drop in glucose levels and increased insulin secretion in C57BL/6J mice. The present study identified PLC??1 and zafirlukast as an important factor that regulates ??-cell insulin secretion. These findings will contribute to an improved understanding of the ??-cell pathophysiology and can be considered as candidate for therapeutic intervention in diabetes mellitus.clos