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Metal halide perovskites are promising light absorbers for multijunction photovoltaic applications because of their remarkable bandgap tunability, achieved through compositional mixing on the halide site. However, poor energy‐level alignment at the interface between wide‐bandgap mixed‐halide perovskites and charge‐extraction layers still causes significant losses in solar‐cell performance. Here, the origin of such losses is investigated, focusing on the energy‐level misalignment between the valence band maximum and the highest occupied molecular orbital (HOMO) for a commonly employed combination, FA0.83Cs0.17Pb(I1‐xBrx)3 with bromide content x ranging from 0 to 1, and poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine] (PTAA). A combination of time‐resolved photoluminescence spectroscopy and numerical modeling of charge‐carrier dynamics reveals that open‐circuit voltage (VOC) losses associated with a rising energy‐level misalignment derive from increasing accumulation of holes in the HOMO of PTAA, which then subsequently recombine non‐radiatively across the interface via interfacial defects. Simulations assuming an ideal choice of hole‐transport material to pair with FA0.83Cs0.17Pb(I1‐xBrx)3 show that such VOC losses originating from energy‐level misalignment can be reduced by up to 70 mV. These findings highlight the urgent need for tailored charge‐extraction materials exhibiting improved energy‐level alignment with wide‐bandgap mixed‐halide perovskites to enable solar cells with improved power conversion efficiencies. [ABSTRACT FROM AUTHOR]

Two dimensional/three‐dimensional (2D/3D) metal halide perovskite heterostructures have attracted great interest in photovoltaic and light‐emitting diode (LEDs) applications. In both, their implementation results in an improvement in device efficiency yet the understanding of these heterostructures remains incomplete. In this work the role of organic cations, essential for the formation of 2D perovskite structures is unraveled, in a range of metal halide perovskite heterostructures. These heterostructures are used to fabricate efficient green perovskite LEDs and a strong dependence between cation content and device performance is shown. The crystal structure, charge‐carrier transport and dynamics, and the electronic structure of these heterostructures are studied and it is shown that the presence of crystalline 2D perovskite inhibits electron injection and ultimately lowers device performance. This work highlights the importance of optimizing the composition of these heterostructures in ensuring optimal device performance across all parameters and suggests that developing routes to inject charge‐carriers directly into 2D perovskite structures will be important in ensuring the continued development of perovskite LEDs based on these heterostructures. [ABSTRACT FROM AUTHOR]

Bioactive peptides (BPs) are protein fragments that benefit human health. To assess whether leftover green tea residues (GTRs) can serve as a resource for new BPs, we performed in silico proteolysis of GTRs using the BIOPEP database, revealing a wide range of BPs embedded in GTRs. Comparative genomics and the percentage of conserved protein analyses enabled us to select a few probiotic strains for GTR hydrolysis. The selected probiotics digested GTRs anaerobically to yield GTR‐derived peptide fractions. To examine whether green tea (GT) peptide fractions could be potential mediators of host–microbe interactions, we comprehensively screened agonistic and antagonistic activities of 168 human G protein‐coupled receptors (GPCRs). NanoLC‐MS/MS analysis and thin‐layer chromatography allowed the identification of peptide sequences and the composition of glycan moieties in the GTRs. Remarkably, GT peptide fractions produced by Lactiplantibacillus plantarum APsulloc 331261, a strain isolated from GT, showed a potent‐binding activity for P2RY6, a GPCR involved in intestinal homeostasis. Therefore, this study suggests the potential use of probiotics‐aided GTR hydrolysates as postbiotic BPs, providing a biological process for recycling GTRs from agro‐waste into renewable resources as health‐promoting BPs. [ABSTRACT FROM AUTHOR]

The intratumoral accumulation of nanomedicine has been considered a passive process, referred to as the enhanced permeability and retention effect. Recent studies have suggested that the tumor uptake of nanomedicines follows an energy‐dependent pathway rather than being a passive process. Herein, to explore the factor candidates that are associated with nanomedicine tumor uptake, a molecular marker identification platform is developed by integrating microscopic fluorescence images of a nanomedicine distribution with spatial transcriptomics information. When this approach is applied to PEGylated liposomes, molecular markers related to hypoxia, glycolysis, and apoptosis can be identified as being related to the intratumoral distribution of the nanomedicine. It is expected that the method can be applied to explain the distribution of a wide range of nanomedicines and that the data obtained from this analysis can enhance the precise utilization of nanomedicines. [ABSTRACT FROM AUTHOR]

Assessment and evaluation are the essential processes of industrially manufactured products for the determination of the quality and quantity of products. They give justifications in a practical way about whether the machine is perfect or imperfect, which can lead to a better or poorer production. In this study, the authors propose an algorithm that uses morphological geodesic active contour and image processing techniques to perform segmentation and assess the performance of a robot used to manufacture welding beads. The algorithm has four parameters which are pre‐processed images, balloon force, smoothing parameter, and number of iterations. To pre‐process the images, the algorithm uses an inverse Gaussian gradient operator for edge detection and applies the histogram equalization method to level the distribution. To detect the external contour of the bead, the level set is initialized as the region of interest whereby a balloon force can inflate or deflate towards the edges. To smoothen the contour, a smoothing parameter is applied to convert the jagged lines into a curve over a reasonable number of iterations. Based on the experimental results, the authors' algorithm used a fixed balloon force of −2, a smoothing parameter value of 4, and 40 iterations to segment images obtained from three different environments. The computation time for the segmentation and evaluation of one image was 0.70, 0.61, and 0.67 s for datasets with high brightness, low brightness, and normal brightness, respectively. Additionally, the authors' proposed algorithm achieved an outstanding performance of 0.9954, 0.9843, 0.9892, and 0.9435 in terms of recall, precision, F‐measure, and IOU, respectively. To justify the performance of the authors' proposed algorithm, the authors compared it with the existing algorithms and found that it worked better than all the others for segmentation, although it lagged behind the entropy‐based algorithm in terms of speed. [ABSTRACT FROM AUTHOR]

Deacylated lipooligosaccharides (dLOSs) were developed as human vaccine adjuvants. The dLOSs have significant immune activities and markedly lower toxicities than their precursors, lipopolysaccharides (LPSs). In this study, we developed a novel liquid chromatography mass spectrometry (LC–MS) method for characterization of the dLOSs. The structural identification and characterization of the dLOSs were carried out using electrospray ionization tandem mass spectrometric experiments. Finally, we propose the most likely structure of the dLOSs as being composed of a diacyl form of lipid A with seven sugars, 3 HEP + 2 KDO + 1 GlcN + 1 Glc. [ABSTRACT FROM AUTHOR]

Contrary to the classic assumptions in the business and human resource (HR) strategy literatures, real‐world organizations often pursue multiple and potentially contradictory performance goals. They may adopt 'hybrid' strategies to maximize both differentiation and low cost — leading middle managers to face dilemmas in how to achieve different goals using the same HR practices. We link employee‐level surveys of HR practices to establishment‐level data on service quality, labour efficiency and profitability to examine the effects of HR practices on these outcomes. We find that establishments with greater use of high involvement practices have significantly higher service quality, which mediates the relationship between HR practices and profitability. Findings for labour efficiency are positive, but generally not significant. These findings also have implications for the quality of jobs. [ABSTRACT FROM AUTHOR]

The production of spherical agglomerates of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) from acetone by cooling crystallization with poly(vinylpyrrolidone) (PVP) is described. It was found that PVP suppresses the nucleation of RDX at the initial stage, but tremendous nucleation of RDX occurred abruptly after the induction period. The rapid nucleation may be associated with the primary nucleation due to the presence of PVP. It can be concluded that the addition of PVP results in the formation of RDX particles with sufficient number density for spherical agglomeration. It was found that such spherical agglomeration propagates very rapidly after nucleation within one minute and the size of spherical agglomerates is affected by the cooling rate. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a new design of a Wilkinson power divider is presented that offers substantially improved amplitude and reduced size characteristics over a broad frequency range compared to a conventional Wilkinson power divider. The improvement in bandwidth is obtained by reducing inductance and number of lumped components in even mode. The analytical design equations for this proposed power divider are obtained using even and odd mode analysis. This power divider with a compact size is fabricated using 65 nm 1P9M CMOS technology. The measurement results show an operation bandwidth 26-40 GHz with 15 dB input, output return loss, and 0.7 dB insertion loss. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:128-131, 2017 [ABSTRACT FROM AUTHOR]

The individual elements of organic light-emitting diode (OLED) displays degrade at different rates, because each element emits light independently; the resulting luminance differences between individual elements cause image sticking-a phenomenon where a displayed text or pattern remains on the screen even after changing the image contents-and are therefore an important issue in OLED displays. However, the introduction of OLED technology into large TV displays is still recent, and no criterion for image sticking evaluation has yet been established. The keystone of a criterion for image sticking evaluation is the definition of the difference level between the luminance of individual elements at which the viewer feels that image sticking is present. Therefore, in this study, an image sticking perception experiment is carried out in accordance with statistically sound procedures for experimental design, using a comprehensive set of human subjects to evaluate the presence of image sticking in moving images. The obtained results are analyzed, and two criteria for image sticking evaluation are proposed. [ABSTRACT FROM AUTHOR]

The fourth High Level Forum on Aid Effectiveness (HLF-4), held in Busan, South Korea drew the largest number as well as the most diverse group of participants ever. This paper examines the shift towards a new global development cooperation paradigm at the Busan HLF-4; the new global partnership that emerged from Busan; and what South Korea brought to the global discourse on development cooperation as an emerging donor. Although it is premature to argue that a new paradigm was established at Busan, there was a clear political momentum for a shift from aid effectiveness to development effectiveness, a change that was advocated and promoted particularly by new actors such as South Korea. The Busan HLF-4 and the post-Busan process have highlighted the global role of new actors, with South Korea exemplifying through its own experience how aid can help bring about development, contributing to the global discourse on development cooperation and playing a bridging role between traditional and emerging donors. The changing dynamics of the world including the global financial crisis and climate change suggest that the global challenges are different from what had been expected when the HLF process and Millennium Development Goals were begun in the beginning of the 20th century. Thus, we recommend that global development cooperation discourse and activities that had been led by traditional Western donors need to find more effective ways of incorporating new actors and different modalities of development cooperation because the global challenges we face are grave. New development partners can bring to the table lessons, energies and capacities deriving from their own dramatic success in alleviating poverty and attaining development and their visibility as global development actors. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents a research on total synthesis of acinetobactin. It states that key heterocyclic rings, namely oxazoline and imidazole, were constructed by a Molybdenum (IV) oxide-catalyzed dehydrative cyclization and a Copper (2+) promoted multi-component condensation. It reports about the preparation of structural analogs of acinetobactin and potent acinetobactin drug conjugates effective in treating drug-resistant A. baumannii.

Since South Korea has historically experienced a great number of natural hazards, the emergency management system has traditionally focused on natural hazards. However, as several large-scale man-made and/or technological disasters have occurred in South Korea in the 1990s, major changes have taken place in Korea`s emergency management systems. Accordingly, this paper examines the emergency management system in South Korea in terms of structural dimensions for emergency management along with the types of disasters. Discussions on theoretical issues of crisis and emergency management are included, but most of this paper is devoted to an overview of Korean emergency management systems as recent responses to disaster. Korea has had to learn the hard way. The Disaster Management Act was established after Korea experienced serious disasters in the mid 1990s. Korea`s emergency management system is still evolving. This paper concludes that emergency management organizations should have coordinating power for a unified response to a crisis as quickly as possible and that the emergency management system in Korea should be equipped with mitigation and preparedness strategies. [ABSTRACT FROM AUTHOR]

2D‐layered transition metal dichalcogenides (TMDCs) such as molybdenum disulfide (MoS2) are promising materials for next‐generation active matrix organic light‐emitting diode (AMOLED) display technology owing to their high mobility and large bandgap size. However, practical applications of TMDCs in driving circuits for flexible displays remain challenging because of the lack of high‐quality large‐area thin films and suitable fabrication processes. Here, millimeter‐scale large‐area bilayer or trilayer MoS2 thin films are synthesized through chemical vapor deposition (CVD) and an AMOLED driver circuit array consisting of bottom‐gate staggered CVD‐grown MoS2 thin‐film transistors is fabricated on a flexible polyimide substrate. The flexible driver circuit exhibits a stable switching and driving operation under tensile strain induced by a bending radius of 3.5 mm, showing field‐effect mobilities of up to ≈9 cm2 V−1 s−1, large ON‐state current density (up to ≈5 µA µm−1), and high ON/OFF‐state drain current ratio (maximum value of over 108) with an operating gate voltage below 10 V. The results demonstrate that MoS2 backplanes are among the promising candidates for next‐generation deformable and transparent AMOLED displays. A flexible active matrix organic light‐emitting diode (AMOLED) pixel driving‐circuit array on a flexible polyimide substrate is demonstrated, thus addressing the current limitations in the application of transition metal dichalcogenides because of the lack of high‐quality large‐area thin films and suitable fabrication processes. [ABSTRACT FROM AUTHOR]

The article discusses the total evaluation and syntheses of the siderophore functions of fimsbactin B and Its analogs. Topics include the resistance to clinically employed antibiotics of the gram-negative bacterium Acinetobacter Baumannii, syntheses of fimsbactin B and its analogs and the relevance of siderophore-related mechanisms in the discovery of antibiotics.