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Diabetes is not solely a metabolic disorder but also involves inflammatory processes. The immune response it incites is a primary contributor to damage in target organs. Research indicates that during the initial phases of diabetic nephropathy, macrophages infiltrate the kidneys alongside lymphocytes, initiating a cascade of inflammatory reactions. The interplay between macrophages and other renal cells is pivotal in the advancement of kidney disease within a hyperglycemic milieu. While M1 macrophages react to the inflammatory stimuli induced by elevated glucose levels early in the disease progression, their subsequent transition to M2 macrophages, which possess anti-inflammatory and tissue repair properties, also contributes to fibrosis in the later stages of nephropathy by transforming into myofibroblasts. Comprehending the diverse functions of macrophages in diabetic kidney disease and regulating their activity could offer therapeutic benefits for managing this condition. [ABSTRACT FROM AUTHOR]

Redox is a constant phenomenon in organisms. From the signaling pathway transduction to the oxidative stress during the inflammation and disease process, all are related to reduction-oxidation (redox). Nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor targeting many antioxidant genes. In non-stressed conditions, NRF2 maintains the hemostasis of redox with housekeeping work. It expresses constitutively with basal activity, maintained by Kelch-like-ECH-associated protein 1 (KEAP1)-associated ubiquitination and degradation. When encountering stress, it can be up-regulated by several mechanisms to exert its anti-oxidative ability in diseases or inflammatory processes to protect tissues and organs from further damage. From acute kidney injury to chronic kidney diseases, such as diabetic nephropathy or glomerular disease, many results of studies have suggested that, as a master of regulating redox, NRF2 is a therapeutic option. It was not until the early termination of the clinical phase 3 trial of diabetic nephropathy due to heart failure as an unexpected side effect that we renewed our understanding of NRF2. NRF2 is not just a simple antioxidant capacity but has pleiotropic activities, harmful or helpful, depending on the conditions and backgrounds. [ABSTRACT FROM AUTHOR]

Treatment for glomerular diseases has been extrapolated from the experience of other autoimmune disorders while the underlying pathogenic mechanisms were still not well understood. As the classification of glomerular diseases was based on patterns of juries instead of mechanisms, treatments were typically the art of try and error. With the advancement of molecular biology, the role of the immune agent in glomerular diseases is becoming more evident. The four-hit theory based on the discovery of gd-IgA1 gives a more transparent outline of the pathogenesis of IgA nephropathy (IgAN), and dysregulation of Treg plays a crucial role in the pathogenesis of minimal change disease (MCD). An epoch-making breakthrough is the discovery of PLA2R antibodies in the primary membranous nephropathy (pMN). This is the first biomarker applied for precision medicine in kidney disease. Understanding the immune system's role in glomerular diseases allows the use of various immunosuppressants or other novel treatments, such as complement inhibitors, to treat glomerular diseases more reasonable. In this era of advocating personalized medicine, it is inevitable to develop precision medicine with mechanism-based novel biomarkers and novel therapies in kidney disease. [ABSTRACT FROM AUTHOR]

• The coupling effect of disorder and rigidity on system's failure behaviors is investigated. • Correlation in disorder has an anomalous effect on the cases of low rigid system. • Crossover in the distribution of avalanches is observed with the influence of disorder and rigidity. Mechanical rigidity and disorder are two important parameters that influence the failure process of solid materials. We investigate the nonlinear mechanics under their coupled effect as well as the influence of disorder's spatial correlation with 2-D network model. The strain–stress relations present strong nonlinearity and rigidity regain phenomenon when there is strong disorder and high rigidity. The correlation of disorder would weaken the effect and has a great influence on the peak stress, initial stiffness, and system toughness. The crossover of power-law exponents of avalanches is observed with consideration of disorder and the transitions in the cluster distribution induced by correlated disorder disappear as the system rigidity decrease. We conclude that although the disorder can be seen as a reduction of average coordinated number for small rupture thresholds system, the correlated disorder still has a great influence on the failure behaviors of heterogeneous materials. [ABSTRACT FROM AUTHOR]

Carboxyl end-functionalized poly(3-hexylthiophene) (P3HT-COOH) was grafted chemically with CdSe nanocrystals (NCs) by a phosphine-free method. The particle quality of P3HT-COOH/CdSe nanocomposites was better than that of P3HT/CdSe nanocomposites, which were synthesized using the same method. Nanocrystals with controllable particle size exhibited a wurtzite crystalline structure and showed excellent nanocrystal dispersion in the P3HT-COOH matrix. Photoluminescence (PL) characterization performed on nanocomposites suggested the efficient charge transfer at the P3HT-COOH/CdSe interface. This approach based on the phosphine-free method is not only environmentally friendly but also highly efficient. [ABSTRACT FROM AUTHOR]

The influences of spatially correlated disorder in microstructure strength are systematic studies in both aspects of failure behaviors and mechanical properties. For the same level of disorder, its spatial distribution has a great influence on failure dynamics and results in different stress–strain responses. The power-law distributions for avalanches and clusters no longer hold when there is a strong correlation between microscope element strength. The brittle and ductile transition is also observed with the change in the disorder's spatial correlation. The results address the importance of the internal correlation structure of disorder and the necessity of considering correlated disorder when studying the failure of heterogeneous materials. • Correlated disorder is introduced and its influence on system's failure behaviors is investigated. • Some universal critical features are broken with the introduction of correlation. • Provide a new viewpoint for study disordered system. [ABSTRACT FROM AUTHOR]

The poly(ethylene glycol) (PEG, with M 2000)-urea inclusion compound (IC) crystallized at high temperature region showed two typical orientations, flat-on and edge-on crystals. 2D-XRD and polarized FTIR spectroscopy revealed that the PEG chains within urea channels were perpendicular to the substrate in flat-on oriented crystals, while PEG chain axes were parallel to the substrate and lay along the growth direction in the edge-on crystals. FTIR absorption bands of PEG in the ICs are sensitive to orientation of the crystals. A scheme of PEG chain packing in the urea IC channel was proposed, which could explain the orientation of the crystal nucleus causing the two types of morphologies. Furthermore, functioning of PEG2000 chain end with analine had significantly influence on the morphology and orientation of the inclusion compound crystals, due to the defects caused by large terminal groups included in the urea channel. [ABSTRACT FROM AUTHOR]

This study presents the green InGaN/GaN multiple quantum wells light-emitting diodes (LEDs) grown on a GaN nanorods template with SiO2 nanomasks by metal-organic chemical vapor deposition. By nanoscale epitaxial lateral overgrowth, microscale air voids were formed between nanorods and the threading dislocations were efficiently suppressed. The electroluminescence measurement reveals that the LEDs on nanorods template with SiO2 nanomasks suffer less quantum-confined Stark effect and exhibit higher light output power and lower efficiency droop at a high injection current as compared with conventional LEDs. [ABSTRACT FROM AUTHOR]

Abstract: We present a study of high quality (11¯01) GaN films and the InGaN/GaN multiple quantum wells (MQWs) using epitaxial lateral overgrowth (ELO) technique by atmospheric pressure metal organic chemical vapor deposition (MOCVD). The smooth coalescence of the stripes and surface morphology was measured by scanning electron microscope (SEM) and atomic force microscopy (AFM). Due to reduction in internal electric field, semipolar InGaN/GaN MQWs have higher radiative recombination rate from time-resolved photoluminescence (TRPL) measurement. In addition, from degree of polarization (DOP) measurement, we observed higher polarization ratio attributed to the induced anisotropic compressive strain. [Copyright &y& Elsevier]

Abstract: A low insertion loss single-pole-single-throw (SPST) pseudomorphic high electron mobility transistor (pHEMT) switch utilizing the n+-type doping in AlAs etching stop layer was fabricated and investigated. This novel design reduces device sheet resistance resulting in an improvement of dc and rf power performance. In addition, the gate recess selectivity for GaAs/AlAs interface was not sacrificed after highly n+-type doping in AlAs etching stop layer. The pHEMT with n+-AlAs etching stop layer, also named Modified pHEMT (M-pHEMT), demonstrated a lower sheet resistance (R sh) of 65.9Ω/γ, a higher maximum drain-to-source current (I dmax) of 317.8mA/mm and a higher peak transconductance (g m) of 259.3mS/mm which are superior to standard pHEMT performance with values of 71.9Ω/γ, 290.3mA/mm and 252.1mS/mm, respectively. Due to a significant sheet resistance improvement from this novel epitaxial design, an SPST pHEMT switch was realized to manifest its industrial application potential. The results achieved an on-state insertion loss of 1.42dB, an off-state isolation of 13.02dB at 0.9GHz, which were superior to traditional pHEMT switch under same condition of operation with values of 1.68dB and 11.42dB, respectively. It is proved that dual n+-doping AlAs etching stop layers scheme is beneficial for low loss microwave switches applications. [Copyright &y& Elsevier]

Atmospheric mercury (Hg) has been monitored at the Lulin Atmospheric Background Station (LABS) in Taiwan since April 2006 and is still continuing. Here we reported the trend in gaseous elemental Hg (GEM) concentrations at LABS between April 2006 and December 2016, before the Minamata Convention on Mercury entered into force in 2017. Previous research indicated nighttime (0–8 am) data collected at LABS are better representative of regional influence. Therefore, only nighttime GEM data were used for trend analysis. A significant decreasing trend in GEM at a rate of −1.5% yr−1 (−0.022 ng m−3 yr−1, p < 0.01) was found, comparable to the decreasing trends observed in Europe, North America, South Africa, and over the North Atlantic Ocean. Five major GEM source regions to the LABS were identified, including northern Indochina Peninsula, China, Northeast Asia, the Pacific Ocean, and South China Sea. Significant decreasing trends in GEM were found for air masses coming from northern Indochina Peninsula (−0.042 ng m−3 yr−1, −2.6% yr−1, p < 0.01), China (−0.041 ng m−3 yr−1, −2.4% yr−1, p < 0.01), Northeast Asia (−0.031 ng m−3 yr−1, −2.0% yr−1, p < 0.05), and the Pacific Ocean (−0.022 ng m−3 yr−1, −1.7% yr−1, p < 0.05). Decreasing GEM trend (−0.020 ng m−3 yr−1, −1.5% yr−1), but insignificant (p > 0.05), was also found for air masses coming from South China Sea. The decreasing trends observed with air from the Pacific Ocean and South China Sea indicated declining background GEM concentrations in Northern Hemisphere. Decrease in GEM concentrations at the LABS was in agreement with the reduction in atmospheric Hg export from the East Asia continent caused by changes in Hg emission quantity and speciation, and temporal and spatial distribution in emission sources that have been suggested by recent research. Additionally, changes in the frequency distribution of air mass origins and transport paths may also contribute to the changes in GEM concentrations at LABS. Unlabelled Image • The first long-term (2006–2016) GEM trend reported from a mountain site downwind of the East Asia continent • A significant decreasing GEM trend was found, comparable to decreasing trends observed in Europe and North America. • Reduction in atmospheric Hg export from East Asia is suggested to contribute to the decreasing GEM trend at LABS. [ABSTRACT FROM AUTHOR]

In this paper, the light emission performance from nonpolar a -plane gallium nitride (GaN)-based photonic crystal (PC) slabs with line-type defect cavities has been investigated. Via the focused ion beam milling technique, thin membrane structures of the nonpolar GaN PC defect cavities were engineered, exhibiting one dominated resonant mode occurred at 419.3 nm with a high quality factor of 1.9\times 10^{3} in the photoluminescence emission characterizations. In the far-field region, light emission performance shows a high polarization degree of 50% with the beam direction perpendicular to the defect cavity. Compared with the PC defect cavity patterns fabricated on c$ -axial oriented GaN materials, the $a$ -plane PC defect cavities display not only the linear light output–input power dependence, but also an invariant resonant mode of constant light emission behavior with increasing the injection carriers, therefore providing a new perspective for the future development of promising optoelectronic devices. [ABSTRACT FROM AUTHOR]

The tumor suppressor p53 is the most frequently mutated protein in human cancer. The majority of these mutations are missense mutations in the DNA binding domain of p53. Restoring p53 tumor suppressor function could have a major impact on the therapy for a wide range of cancers. Here we report a virtual screening approach that identified several small molecules with p53 reactivation activities. The UCI-LC0023 compound series was studied in detail and was shown to bind p53, induce a conformational change in mutant p53, restore the ability of p53 hotspot mutants to associate with chromatin, reestablish sequence-specific DNA binding of a p53 mutant in a reconstituted in vitro system, induce p53-dependent transcription programs, and prevent progression of tumors carrying mutant p53, but not p53null or p53WT alleles. Our study demonstrates feasibility of a computation-guided approach to identify small molecule corrector drugs for p53 hotspot mutations. [Display omitted] • Small molecules targeting a cryptic L1/S3 pocket of p53 are identified • Experimental validation led to the identification of mutant p53 reactivators • Compounds restore DNA binding of p53MUT in vitro and in vivo • Compounds directly bind to p53MUT and exert anti-tumor effect in tumor models A large fraction of human tumors inactivate the major tumor suppressor p53 by mutations. Corrector drugs reactivating mutant p53 are of high clinical value for cancer therapy. Durairaj et al. identify small drug-like compounds that restore wild-type activity to mutant forms of p53 and exhibit anti-tumor effects. [ABSTRACT FROM AUTHOR]

Concentrations of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particle-bound mercury (PBM) were measured at a suburban site in northern Taiwan between October 2017 and September 2018. Mean concentrations of GEM, GOM, and PBM were 2.61 ± 6.47 ng m−3, 12.1 ± 34.3 pg m−3, and 18.7 ± 86.8 pg m−3, respectively. On 35% of the days, elevated atmospheric mercury (Hg) concentration occurred between midnight and early morning when local wind direction shifted and came from sectors between SSW and S, indicating influence of local anthropogenic emission sources. As such, a diurnal pattern with nighttime peaks was observed for GEM, GOM, and PBM. However, elevated GOM values were also observed around noon on 87 occasions, coinciding with peak O 3 and solar radiation, suggesting additional contribution from in situ photochemical reactions. Seasonally, atmospheric Hg concentrations were higher in spring than in the other seasons. Besides the contribution from local emissions and the East Asian outflow, lower wind speed, cumulative rainfall, and days of rain in spring suggesting poor air dispersion and inefficient pollutant removal, hence leading to the accumulation of atmospheric Hg and thus higher concentrations. Two trans-boundary haze events from China were encountered during this study. Concentrations of GEM and PBM were enhanced on haze days, with particularly significant enhancement in PBM. Comparison of the maximum PBM values during these haze events to respective pre-event PBM values showed enhancements of 378% and 1438%, whereas enhancements of 100% and 147% were observed for GEM. GOM remained relatively low and stable during haze events, which could be due to the favored partitioning of GOM toward solid phase under high PM 2.5 concentrations and the lack of sunlight to fuel the photochemical production of GOM. Backward trajectories indicated that Hg emissions in east China likely contributed to the enhancements in atmospheric Hg concentrations measured at the suburban site in northern Taiwan during these two trans-boundary haze events. • Both local sources and regional transport contributed to the measured atmospheric Hg. • Two trans-boundary haze events from China were encountered. • Concentrations of GEM and PBM were enhanced on haze days, but GOM remained low. • Yangtze River Delta and east China were the Hg source regions for these haze events. [ABSTRACT FROM AUTHOR]

The Asia Pacific Mercury Monitoring Network (APMMN) cooperatively measures mercury in precipitation in a network of sites operating in Asia and the Western Pacific region. The network addresses significant data gaps in a region where mercury emission estimates are the highest globally, and available measurement data are limited. The reduction of mercury emissions under the Minamata Convention on Mercury also justifies the need for continent-wide and consistent observations that can help determine the magnitude of the problem and assess the efficacy of reductions over time. The APMMN's primary objectives are to monitor wet deposition and atmospheric concentrations of mercury and assist partners in developing their own monitoring capabilities. Network planning began in 2012 with wet deposition sampling starting in 2014. Currently, eight network sites measure mercury in precipitation following standardized procedures adapted from the National Atmospheric Deposition Program. The network also has a common regional analytical laboratory (Taiwan), and quality assurance and data flagging procedures, which ensure the network makes scientifically valid and consistent measurements. Results from our ongoing analytical and field quality assurance measurements show minimal contamination in the network and accurate analytical analyses. We are continuing to monitor a potential concentration and precipitation volume bias under certain conditions. The average mercury concentration in precipitation was 11.3 (+9.6) ng L−1 for 139 network samples in 2018. Concentrations for individual sites vary widely. Low averages compare to the low concentrations observed on the U.S. West Coast; while other sites have average concentrations similar to the high values reported from many urban areas in China. Future APMMN goals are to (1) foster new network partnerships, (2) continue to collect, quality assure, and distribute results on the APMMN website, (3) provide training and share best monitoring practices, and (4) establish a gaseous concentration network for estimating dry deposition. [ABSTRACT FROM AUTHOR]