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T cells play an important role in the development of focal segmental glomerulosclerosis (FSGS). The mechanism underlying such T cell‐based kidney disease, however, remains elusive. Here the authors report that activated CD8 T cells elicit renal inflammation and tissue injury via releasing miR‐186‐5p‐enriched exosomes. Continuing the cohort study identifying the correlation of plasma level of miR‐186‐5p with proteinuria in FSGS patients, it is demonstrated that circulating miR‐186‐5p is mainly derived from activated CD8 T cell exosomes. Renal miR‐186‐5p, which is markedly increased in FSGS patients and mice with adriamycin‐induced renal injury, is mainly delivered by CD8 T cell exosomes. Depleting miR‐186‐5p strongly attenuates adriamycin‐induced mouse renal injury. Supporting the function of exosomal miR‐186‐5p as a key circulating pathogenic factor, intravenous injection of miR‐186‐5p or miR‐186‐5p‐containing T cell exosomes results in mouse renal inflammation and tissue injury. Tracing the injected T cell exosomes shows their preferential distribution in mouse renal tubules, not glomerulus. Mechanistically, miR‐186‐5p directly activates renal tubular TLR7/8 signal and initiates tubular cell apoptosis. Mutating the TLR7‐binding sequence on miR‐186‐5p or deleting mouse TLR7 largely abolishes renal tubular injuries induced by miR‐186‐5p or adriamycin. These findings reveal a causative role of exosomal miR‐186‐5p in T cell‐mediated renal dysfunction. [ABSTRACT FROM AUTHOR]

Bioremediation of crude oil (or petroleum) pollution in the saline-alkali environment is challenging due to the lack of halotolerant and alkali tolerant oil-degrading bacteria. It is shown here that a newly isolated Acinetobacter strain D2 able to degrade crude oil was moderately haloalkaliphilic. Physiological characterization showed that the optimal crude oil degradation conditions for D2 strain occurred at pH = 9 and NaCl concentration of 2% w/v. Moreover, D2 can tolerate pH 11 and NaCl concentration of 8% w/v. Kinetic analysis indicated that crude oil (0.2% and 0.5% w/v) biodegradation by D2 followed the first-order kinetic model, with the k constant estimated as 0.089–0.111 d−1 and the half-life period of petroleum degradation as 6.24–7.79 d. The results of the gas chromatographic analysis revealed that strain D2 could degrade most saturated hydrocarbons, with higher removal efficiencies for shorter-chain alkanes. Strain D2 can also remove aromatic hydrocarbons with an average efficiency of 33.4%. Combined, these results demonstrated that a moderately haloalkaliphilic Acinetobacter strain can be a suitable candidate for bioremediation of oil-contaminated saline soil and oilfield produced water. [ABSTRACT FROM AUTHOR]

• Viruses exploit a common survival strategy of inducing host cell polyribonucleotide nucleotidyltransferase 1 (PNPT1). • PNPT1 mitigates the integrated stress response mediated by mitochondrial double-stranded RNAs (mt-dsRNAs) during viral propagation. • PNPT1 depletion inhibits pan-viral propagation by activating the mt-dsRNA-RNA-activated protein kinase-eukaryotic initiation factor 2α signal axis. • The PNPT1 inhibitor, lanatoside C, was identified as a potent blocker of pan-viral propagation. For successful viral propagation within infected cells, the virus needs to overcome the cellular integrated stress response (ISR), triggered during viral infection, which, in turn, inhibits general protein translation. This paper reports a tactic employed by viruses to suppress the ISR by upregulating host cell polyribonucleotide nucleotidyltransferase 1 (PNPT1). The propagation of adenovirus, murine cytomegalovirus and hepatovirus within their respective host cells induces PNPT1 expression. Notably, when PNPT1 is knocked down, the propagation of all three viruses is prevented. Mechanistically, the inhibition of PNPT1 facilitates the relocation of mitochondrial double-stranded RNAs (mt-dsRNAs) to the cytoplasm, where they activate RNA-activated protein kinase (PKR). This activation leads to eukaryotic initiation factor 2α (eIF2α) phosphorylation, resulting in the suppression of translation. Furthermore, by scrutinizing the PNPT1 recognition element and screening 17,728 drugs and bioactive compounds approved by the US Food and Drug Administration, lanatoside C was identified as a potent PNPT1 inhibitor. This compound impedes the propagation of adenovirus, murine cytomegalovirus and hepatovirus, and suppresses production of the severe acute respiratory syndrome coronavirus-2 spike protein. These discoveries shed light on a novel strategy to impede pan-viral propagation by activating the host cell mt-dsRNA-PKR-eIF2α signalling axis. [ABSTRACT FROM AUTHOR]

The treatment of chronic diabetic wounds remains challenging due to the rapid bacterial infection, severe inflammation, and insufficient angiogenesis. To address these challenges, a novel multifunctional composite nanoparticle is developed by co -assembling antisolvent-induced co-assembling silk-fibroin ε-poly- l -Lysine nanoparticles (nSF-EPL) and further assembling nSF-EPL with polydeoxyribonucleotide (PDRN) and exosome derived from human umbilical mesenchymal stem cells (Exo). Owing to the modification of EPL, PDRN and Exo, composite nanoparticles exhibited synergistic antibacterial action, anti-inflammatory and angiogenesis, which can significantly benefit for promoting wound healing. Release results show that the composite nanoparticles exhibit long-term sustained PDRN and Exo release profiles as well as outstanding release efficiency. Furthermore, in vitro studies show that the composite nanoparticles exhibit effective antibacterial activity, thus inducing an anti-inflammatory M2 macrophages phenotype and promoting angiogenesis. In vivo research results of investigations pertaining to diabetic wound healing show that the composite nanoparticles have good anti-inflammatory and angiogenesis capabilities, which can promote granulation tissue formation, collagen deposition, wound tissue epithelialization, and significantly accelerate skin healing. This study presents a promising strategy for the clinical treatment of chronic diabetic wounds. [ABSTRACT FROM AUTHOR]

An optimized structure is of considerable importance for nickle oxide (NiO)‐based materials to achieve high performance as catalyst for contaminant degradation due to the inherent large band gap. Herein, a series of hybrids of NiO nanoparticles doped with zinc oxide (ZnO) semiconductor were fabricated via a facile one‐step calcination of bimetallic metal‐organic frameworks with varied Ni2+/Zn2+ molar ratios (MOF‐NiZn). It is worth noting that partial positions of Ni in NiO lattice are replaced by Zn to form a Ni0.9Zn0.1O phase. Benefiting from the unique hybrid advantage, the rationally designed material could effectively lower the band gap of NiO, thus improving the photocatalytic performance. The optimized ZnO/Ni0.9Zn0.1O‐82 catalyst exhibits the highest degradation activity towards methylene blue (MB) with efficiency up to 97.4 % within 60 min. Additionally, the radicals trapping experiments reveal that the photo‐generated hydroxyl radical (.OH) is the predominant active species during the photodegradation of MB. [ABSTRACT FROM AUTHOR]

In specific, miR-186-5p is enriched in exosomes of activated CD8 T cells and preferentially enters renal tubular cells where it directly binds endosomal TLR7/8 and initiates renal inflammation. CD8 T Cell-Derived Exosomal miR-186-5p Elicits Renal Inflammation via Activating Tubular TLR7/8 Signal Axis (Adv. Sci. 25/2023) In article number 2301492, Ke Zen, Zhihong Liu, and co-workers identify exosomal miR-186-5p from activated CD8 T cells as such circulating pathogenic factor that causes renal dysfunction. [Extracted from the article]

Entomopathogenic fungi can invade wide range of insect hosts in the natural world and have been used as environmentally friendly alternatives to chemical insecticides for pest control. Studies of host-pathogen interactions provide valuable insights into the coevolutionay arms race between fungal pathogens and their hosts. Entomopathogenic fungi have evolved a series of sophisticated strategies to counter insect immune defenses. In response to fungal infection, insect hosts rely on behavior avoidance, physical barrier and innate immune defenses in the fight against invading pathogens. The insect cuticle acts as the first physical barrier against pathogens. It is an inhospitable physiological environment that contains chemicals (e.g., antimicrobial peptides and reactive oxygen species), which inhibit fungal growth. In addition, innate immune responses, including cellular immunity and humoral immunity, play critical roles in preventing fungal infection. In this review, we outline the current state of our knowledge of insect defenses to fungal infection and discuss the strategies by which entomopathogenic fungi counter the host immune system. Increased knowledge regarding the molecular interactions between entomopathogenic fungi and the insect host could provide new strategies for pest management. [ABSTRACT FROM AUTHOR]

It is acknowledged that postnatal mammalian cardiomyocytes (CMs) turn over with a very limited efficacy in both physiological and pathological conditions. Recent studies showed that those newly formed CMs are derived from preexisting CMs. Thus, stimulating CM proliferation becomes a promising strategy for inducing cardiac regeneration. Noncoding RNAs were found differently expressed in CMs with different proliferation potential. Moreover, manipulation of noncoding RNAs, in particular microRNAs, was proved to promote or suppress CM proliferation, indicating that noncoding RNAs are involved in the underlying mechanism of CM proliferation. This review mainly summarizes the roles of noncoding RNAs, as a class of influential factors, in the regulation of CM proliferation. [ABSTRACT FROM AUTHOR]

Influenza is caused by a respiratory virus and has a major global impact on human health. Influenza A viruses in particular are highly pathogenic to humans and have caused multiple pandemics. An important consequence of infection is viral pneumonia, and with serious complications of excessive inflammation and tissue damage. Therefore, simultaneously reducing direct damage caused by virus infection and relieving indirect damage caused by excessive inflammation would be an effective treatment strategy. Lycium barbarum glycopeptide (LbGp) is a mixture of five highly branched polysaccharide-protein conjuncts (LbGp1-5) isolated from Lycium barbarum fruit. LbGp has pro-immune activity that is 1–2 orders of magnitude stronger than that of other plant polysaccharides. However, there are few reports on the immunomodulatory and antiviral activities of LbGp. In this study, we evaluated the antiviral and immunomodulatory effects of LbGp in vivo and in vitro and investigated its therapeutic effect on H1N1-induced viral pneumonia and mechanisms of action. In vitro , cytokine secretion, NF-κB p65 nuclear translocation, and CD86 mRNA expression in LPS-stimulated RAW264.7 cells were constrained by LbGp treatment. In A549 cells, LbGp can inhibit H1N1 infection by blocking virus attachment and entry action. In vivo experiments confirmed that administration of LbGp can effectively increase the survival rate, body weight and decrease the lung index of mice infected with H1N1. Compared to the model group, pulmonary histopathologic symptoms in lung sections of mice treated with LbGp were obviously alleviated. Further investigation revealed that the mechanism of LbGp in the treatment of H1N1-induced viral pneumonia includes reducing the viral load in lung, regulating the phenotype of pulmonary macrophages, and inhibiting excessive inflammation. In conclusion, LbGp exhibits potential curative effects against H1N1-induced viral pneumonia in mice, and these effects are associated with its good immuno-regulatory and antiviral activities. • LbGp can inhibit IAV infection, its antiviral activity is related to blocking the process of virus attachment and entry. • LbGp has immunomodulatory effects on macrophages by regulating NF-κB related signaling pathways and phenotype. • LbGp alleviates H1N1 induced viral pneumonia in mice. • LbGp has curative effects on pneumonia caused by H1N1, which are related to its immune regulation and antiviral activity. [ABSTRACT FROM AUTHOR]

The development of high-efficient and cost-effective electrocatalysts is crucial to remove nitrate pollutant in wastewater. Herein, we design and prepare mesoporous Co-doped Cu 2 (OH) 2 CO 3 malachite nanosheets as an electrocatalyst toward highly efficient nitrate reduction using a facile CO 2 bubble-assisted coprecipitation synthesis. The electrocatalytic performance is subject to the Co/Cu ratio of this malachite. Remarkably, compared with the pristine monometal Cu or Co-based electrocatalyst, the optimal electrocatalyst, 0.3Co@Cu 2 (OH) 2 CO 3 , displays fast and highly efficient removal capacity of nitrate with an impressive high total nitrogen (TN) removal of 8628.99 mg N g−1 CoCu (398.79 mg N g cat −1 h−1), N 2 selectivity of 97.11% as well as negligible nitrite product at 100 mg L−1 NO 3 --N and 2000 mg L−1 Cl- neutral electrolyte. Above all, high total nitrogen removal efficiency (81.92%) and chemical oxygen demand (73.74%) in actual wastewater. Its excellent electrocatalytic performance is achieved by regulating the electronic structure and the adsorption/desorption of the intermediate. This study discovers a new type of electrode materials for nitrate removal in wastewater. [Display omitted] • Mesoporous Co-doped Cu 2 (OH) 2 CO 3 nanosheets have been synthesized by an in-situ CO 2 template. • 0.3@Cu 2 (OH) 2 CO 3 catalyst has excellent NO 3 reduction performance and long-term durability. • 0.3@Cu 2 (OH) 2 CO 3 catalyst displays fast and impressive high total nitrogen (TN) removal. • DFT results show its unique structure and composition improve electrocatalytic performance. [ABSTRACT FROM AUTHOR]

Validamycin A (VAL-A) is a CN aminocyclitol antibiotic produced by Streptomyces hygroscopicus var. jinggangensis 5008, which has been widely used as antifungal agent against rice sheath blight disease. VAL-A biosynthesis has been proven to be affected by γ-butyrolactone and temperature. Herein, we showed that GlnR, a global regulator in nitrogen metabolism, is specifically associated with valK-valA intergenic promoter region by DNA-affinity chromatography and MS-based protein identification. Subsequent EMSA and DNase I footprinting assays revealed two GlnR binding sites in this promoter region. Targeted disruption of glnR in S. hygroscopicus 5008 led to a significant increase in the transcription of VAL-A structural genes, albeit the VAL-A production was reduced by 80 % and the sporulation of the mutant was impaired. Compared with the wild-type 5008, site-specific mutagenesis of GlnR binding site I enhanced VAL-A production by 2.5-fold, whereas the mutation of GlnR binding site II resulted in a 50 % reduction of VAL-A yield. Moreover, tandem mutation of site I in the site II mutant led to a 66 % increase of VAL-A production. The result suggested that GlnR not only serves as an inhibitor by binding site I but also as an activator by binding site II for VAL-A biosynthesis. Furthermore, overexpression of glnR in the site I mutant JG45 improved VAL-A production for 41 % compared with the control strain containing the vector. Therefore, the obtained data illustrate a novel regulatory feature of the global regulator GlnR. GlnR is firstly proved to act simultaneously as an activator and a repressor in validamycin biosynthesis by binding to different loci within a promoter region of the gene cluster. [ABSTRACT FROM AUTHOR]

BACKGROUND Internal tandem duplication of FMS-like tyrosine kinase (FLT3-ITD) is well known to be involved in acute myeloid leukemia (AML) progression, but FLT3-ITD-negative AML cases account for 70% to 80% of AML, and the mechanisms underlying their pathology remain unclear. This study identifies protein tyrosine phophatase PRL-3 as a key mediator of FLT3-ITD-negative AML. METHODS A total of 112 FLT3-ITD-negative AML patients were sampled between 2010 and 2013, and the occurrence of PRL-3 hyperexpression in FLT3-ITD-negative AML was evaluated by multivariate probit regression analysis. Overexpression or depletion of endogenous PRL-3 expression with the specific small interfering RNAs was performed to investigate the role of PRL-3 in AML progression. Xenograft models were also used to confirm the oncogenic role of PRL-3. RESULTS Compared to healthy donors, PRL-3 is upregulated more than 3-fold in 40.2% of FLT3-ITD-negative AML patients. PRL-3 expression level is adversely correlated to the overall survival of the AML patients, and the AML relapses accompany with re-upregulation of PRL-3. Mechanistically, aberrant PRL-3 expression promoted cell cycle progression and enhanced the antiapoptotic machinery of AML cells to drug cytotoxicity through downregulation of p21 and upregulation of Cyclin D1 and CDK2 and activation of STAT5 and AKT. Depletion of endogenous PRL-3 sensitizes AML cells to therapeutic drugs, concomitant with apoptosis by upregulation of cleaved PARP (poly ADP ribose polymerase) and apoptosis-related caspases. Xenograft assays further confirmed PRL-3's oncogenic role in leukemogenesis. CONCLUSIONS Our results demonstrated that PRL-3 is a novel independent crucial player in both FLT3-ITD-positive and FLT3-ITD-negative AML and could be a potential therapeutic target. Cancer 2014;120:2130-2141. © 2014 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. [ABSTRACT FROM AUTHOR]

Abstract: The effect of misorientation of 6H–SiC substrate on the structural quality of GaN epilayer grown by organometallic vapor phase epitaxy (MOVPE) has been investigated. The results reveal that the structural quality of GaN epilayer is significantly influenced by the misorientation of 6H–SiC substrate. Larger misorientation angle of 6H–SiC substrate results in better structural quality of GaN epilayer, such as narrower atomic step widths of GaN surface, less yellow luminescence band/edge emission (I y /I b ) ratio of PL, and lower dislocations density. It is also found that the I y /I b ratio of GaN epilayer is affected only by the misorientation angle of 6H–SiC substrate, but the screw dislocation density and edge dislocation density are influenced by both the misorientation angle and the misorientation direction of 6H–SiC substrate. GaN epilayer grown on 6H–SiC substrate with 2.3° misorientation angle towards direction has the best structural quality. [Copyright &y& Elsevier]

Abstract: The influence of AlN buffer growth temperature on the quality and stress of 4.5μm GaN epilayer on 6H–SiC substrate by organometallic vapor phase epitaxy (MOVPE) has been investigated. The crystalline quality and the atomic surface morphology were improved, the density of the pits and the stress of the GaN epilayer were reduced by increasing the growth temperature of the AlN buffer in the range from 950°C to 1100°C. By employing the optimized 1100°C growth temperature of AlN buffer, very high quality of GaN epilayer was achieved. The X-ray full width of half maximums (FWHMs) of (002) and (102) reflection rocking curves of the GaN epilayer have been improved to 159arcsec and 194arcsec, respectively, and the surface RMS to only 0.31nm in the 5μm×5μm atomic force microscopy (AFM) scan. The stress of GaN epilayer was investigated by X-ray diffraction and Raman scattering as well. The degree of the tensile stress in GaN epilayer could be suppressed by increasing the growth temperature of AlN buffer. Finally, a high quality of crack-free 4.5μm thick GaN epilayer was obtained on 6H–SiC substrate using the optimized 1100°C AlN growth temperature. [Copyright &y& Elsevier]

New poly(ethylene terephthalate) (PET)-based poly(ether-ester)s were successfully synthesized, by using the bi co mponent catalyst of titanium isopropoxide (TPT) and methanesulfonic acid (MSA) to directly catalyze polycondensation of terephthalic acid and ethylene glycol, for randomly copolymerizing poly(ethylene terephthalate) (PET), poly(diethylene terephthalate) (PDET) and poly(ethylene oxide terephthalate) (PEOT), which denoted as linear PET- co -PDET- co -PEOT. The chemical structures of PET- co -PDET- co -PEOT were evidenced by two-dimensional and one-dimensional nuclear magnetic resonance (2D and 1D-NMR) techniques, and the segment contents of the poly(ether-ester) were tunable by adjusting the feeding molar ratios of catalytic systems. The thermal properties, mechanical properties and rheological behavior of linear PET- co -PDET- co -PEOTs were studied in detail. In particular, the branched PET- co -PDET- co -PEOT were afforded via introducing the multifunctional reagents, such as 1,1,1-tris(hydroxymethyl) ethane (TME), 2,2-dimethylolpropionic acid (DMPA) or 1,2,3-propanetricarboxylic acid (PTA). Compared to linear PET- co -PDET- co -PEOTs, the elongation at break of the branched PET- co -PDET- co -PEOTs were strongly enhanced to 409%, and their flow properties were accordingly altered, as revealed by rheological analysis. The novel PET-based poly(ether-ester)s will be promising as potential thermal elastomers. [Display omitted] • The synthesis of PET-based PEEs via direct polycondensation of TA and EG • The first report on the PEEs with poly(diethylene terephthalate) (PDET) as the soft segment. • PET-based PEEs exhibited striking mechanical properties and elasticity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Experimental and theoretical research on the fire resistance of reinforced concrete beams is summarized. • The important parameters are selected by parameter correlation analysis. • The fire resistance prediction equation is proposed by Machine Learning and regression analysis. Reinforced concrete (RC) beams are widely applied in building structures, and fire resistance performance becomes a focus of fire research with the high frequency of building fires. This paper aims to summarize the fire resistance performance of 216 specimens in 80 references and propose a fire resistance prediction equation. Firstly, the factors of fire resistance are considered in these specimens such as load ratio, concrete cover thickness and longitudinal reinforcement ratio. The influence rules of these factors are summarized. And the theoretical analysis, finite element simulation and fire resistance prediction equation of RC beams are also summarized. It is found that the parameters such as load ratio and concrete cover thickness have a great impact on fire resistance, while the parameters such as stirrup spacing have a minor impact on fire resistance. Secondly, the Pearson correlation analysis of 10 parameters is conducted in 216 specimens and 6 parameters with a correlation degree greater than 0.1 are identified as important parameters. The database is established by 4 Machine Learning (ML) algorithms. It is found that the database established by the Random Forest (RF) algorithm has high performance. Finally, the fire resistance prediction equation of RC beam is obtained by the database and nonlinear regression analysis. The prediction equation is compared with existing equations, and it is found that the proposed equation with R 2 of 0.935 has high precision in predicting fire resistance. The proposed equation can be adopted to guide the fire resistance design of RC beams. [ABSTRACT FROM AUTHOR]

Mono‐methylation of histone H3 on Lys 4 (H3K4me1), which is catalyzed by histone‐lysine N‐methyltransferase 2D (KMT2D), serves as an important epigenetic regulator in transcriptional control. In this study, the authors identify early B‐cell factor 2 (EBF2) as a binding protein of H3K4me1. Combining analyses of RNA‐seq and ChIP‐seq data, the authors further identify killin (KLLN) as a transcriptional target of KMT2D and EBF2 in pancreatic ductal adenocarcinoma (PDAC) cells. KMT2D‐dependent H3K4me1 and EBF2 are predominantly over‐lapped proximal to the transcription start site (TSS) of KLLN gene. Comprehensive functional assays show that KMT2D and EBF2 cooperatively inhibit PDAC cells proliferation, migration, and invasion through upregulating KLLN. Such inhibition on PDAC progression is also achieved through increasing H3K4me1 level by GSK‐LSD1, a selective inhibitor of lysine‐specific demethylase 1 (LSD1). Taken together, these findings reveal a new mechanism underlying PDAC progression and provide potential therapeutic targets for PDAC treatment. [ABSTRACT FROM AUTHOR]

Background: Juglans sigillata L. (walnut) has a high economic value for nuts and wood and has been widely grown and eaten around the world. Light plays an important role in regulating the development of the walnut embryo and promoting nucleolus enlargement, which is one of the factors affecting the yield and quality of walnut. However, little is known about the effect of light on the growth and quality of walnuts. Studies have shown that far red prolonged hypocotyl 3 (FHY3) and far red damaged response (FAR1) play important roles in plant growth, light response, and resistance. Therefore, FHY3/FAR1 genes were identified in walnuts on a genome-wide basis during their growth and development to reveal the potential regulation mechanisms involved in walnut kernel growth and development. Results: In the present study, a total of 61 FHY3/FAR1 gene family members in walnuts have been identified, ranging in length from 117 aa to 895 aa. These gene family members have FHY3 or FAR1 conserved domains, which are unevenly distributed on the 15 chromosomes (Chr) of the walnut (except for the Chr16). All 61 FHY3/FAR1 genes were divided into five subclasses (I, II, III, IV, and V) by phylogenetic tree analysis. The results indicated that FHY3/FAR1 genes in the same subclasses with similar structures might be involved in regulating the growth and development of walnut. The gene expression profiles were analyzed in different walnut kernel varieties (Q, T, and F). The result showed that some FHY3/FAR1 genes might be involved in the regulation of walnut kernel ripening and seed coat color formation. Seven genes (OF07056-RA, OF09665-RA, OF24282-RA, OF26012-RA, OF28029-RA, OF28030-RA, and OF08124-RA) were predicted to be associated with flavonoid biosynthetic gene regulation cis-acting elements in promoter sequences. RT-PCR was used to verify the expression levels of candidate genes during the development and color change of walnut kernels. In addition, light responsiveness and MeJA responsiveness are important promoter regulatory elements in the FHY3/FAR1 gene family, which are potentially involved in the light response, growth, and development of walnut plants. Conclusion: The results of this study provide a valuable reference for supplementing the genomic sequencing results of walnut, and pave the way for further research on the FHY3/FAR1 gene function of walnut. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the incidences of pre- and post-operative lower extremity deep venous thrombosis (DVT) in hospitalized patients with intertrochanteric fractures and to analyze the relevant risk factors. Methods: A retrospective study was conducted between July 2014 and October 2016 in 218 intertrochanteric fracture patients who presented at Xi'an Honghui Hospital and underwent Doppler ultrasonography for DVT diagnosis. We divided DVT into distal, proximal, and mixed thrombosis. Patients were divided into either the thrombosis or no thrombosis group according to preoperative and postoperative ultrasonography results. All patients were evaluated for the risk factors associated with thrombosis. Results: A total of 37.61% of preoperative patients had DVT, and the postoperative incidence increased to 58.72%. The days between fracture and hospitalization and the days between fracture and surgery were independent risk factors for preoperative DVT. The days between fracture and hospitalization and d-dimer levels at postoperative 1 day were independent risk factors of postoperative DVT. In total 23.4% of the patients progressed from having no thrombosis preoperatively to having distal, proximal, or mixed DVT postoperatively (22.02%, 0.46%, and 0.92%, respectively). Distal DVT constituted 86.59% and 90.63% of all preoperative and postoperative DVTs, respectively. Conclusion: Intertrochanteric fracture is a common type of hip fracture in the elderly, and the incidence of DVT after intertrochanteric fracture may be underestimated. Early intervention (early admission and early surgery) might reduce the incidence of DVT. [ABSTRACT FROM AUTHOR]

Background: Perioperative anxiety is common in pediatric patients undergoing surgery. Aims: The aim of this study was to determine whether an infusion of dexmedetomidine prior to hernia repair in children provides better postoperative anxiety outcomes that a preoperative infusion of midazolam. Methods: Ninety 6‐11‐year‐old children, who were scheduled to undergo elective hernia repair, were enrolled for this double‐blind, randomized controlled trial. Group D (n = 45) received an intravenous infusion of dexmedetomidine (0.5 μg/kg) and Group M (n = 45) received an intravenous infusion of midazolam (0.08 mg/kg) in 20 mL of normal saline for 10 minutes before the induction of anesthesia. Pre‐ and postoperative scores on the modified Yale Preoperative Anxiety Scale were the main outcomes. Secondary outcomes included systolic blood pressure, diastolic blood pressure, heart rate, and postoperative pain measured on a visual analogue scale and patient satisfaction using a numerical rating scale. Results: Postoperative anxiety in Group D was significantly lower than preoperative anxiety (2 hours postoperatively mean difference [95% CI]: 2.83 [0.87‐4.79], P = 0.036, 4 hours postoperatively mean difference [95% CI]: 3.29 [1.39‐5.20], P = 0.005). Preoperative and postoperative anxiety in Group M was similar. Anxiety scores in Group D were also significantly lower than anxiety in Group M 2 hours (mean difference [95% CI]: 1.89 [0.52‐3.26], P = 0.01) and 4 hours (mean difference [95% CI]: 3.32 [1.98‐4.66], P < 0.001) postoperatively. Systolic blood pressure, diastolic blood pressure and heart rate were lower in Group D than in Group M after administration of sedative drugs until children left PACU (SBP mean difference [95% CI]: 13.87 [10.30‐17.43], P < 0.001, DBP mean difference [95% CI]: 5.96[3.80‐8.11], P < 0.001, HR mean difference [95% CI]: 10.36 [7.58‐13.13], P < 0.001). Pain was also significantly lower in Group D than in Group M at 2 hours (median difference [95% CI]: 1 [0.26‐1.34], P = 0.004), 4 hours (median difference [95% CI]: 1 [0.31‐1.02], P = 0.003), and 1 day (median difference [95% CI]: 0 [0.22‐0.76], P = 0.003) postoperatively. Patient satisfaction scores were significantly higher in Group D than in Group M 1 day (median difference [95% CI]: 0 [−0.83 to −0.24], P = 0.006) and somewhat higher 1 week (median difference [95% CI]: 0 [−0.67 to −0.04], P = 0.06) postoperatively. Conclusion: Compared with midazolam, a single preoperative intravenous dose of dexmedetomidine appears to provide better postoperative anxiolytic effects for children undergoing same‐day surgery. [ABSTRACT FROM AUTHOR]

Extracellular microRNAs (miRNAs) play a critical role in horizontal gene regulation. Uptake of extracellular miRNAs by recipient cells and their intracellular transport, however, remains elusive. Here RNA phase separation is shown as a novel pathway of miRNA uptake. In the presence of serum, synthetic miRNAs rapidly self‐assembly into ≈110 nm discrete nanoparticles, which enable miRNAs' entry into different cells. Depleting serum cationic proteins prevents the formation of such nanoparticles and thus blocks miRNA uptake. Different from lipofectamine‐mediated miRNA transfection in which majority of miRNAs are accumulated in lysosomes of transfected cells, nanoparticles‐mediated miRNA uptake predominantly delivers miRNAs into mitochondria in a polyribonucleotide nucleotidyltransferase 1(PNPT1)‐dependent manner. Functional assays further show that the internalized miR‐21 via miRNA phase separation enhances mitochondrial translation of cytochrome b (CYB), leading to increase in adenosine triphosphate (ATP) and reactive oxygen species (ROS) reduction in HEK293T cells. The findings thus reveal a previously unrecognized mechanism for uptake and delivery functional extracellular miRNAs into mitochondria. [ABSTRACT FROM AUTHOR]

Bacterial pneumonia is one of the leading causes of death worldwide and exerts a significant burden on health-care resources. Antibiotics have long been used as first-line drugs for the treatment of bacterial pneumonia. However, antibiotic therapy and traditional antibiotic delivery are associated with important challenges, including drug resistance, low bioavailability, and adverse side effects; the existence of physiological barriers further hampers treatment. Fortunately, these limitations may be overcome by the application of nanotechnology, which can facilitate drug delivery while improving drug stability and bioavailability. This review summarizes the challenges facing the treatment of bacterial pneumonia and also highlights the types of nanoparticles that can be used for antibiotic delivery. This review places a special focus on the state-of-the-art in nanomaterial-based approaches to the delivery of antibiotics for the treatment of pneumonia. [ABSTRACT FROM AUTHOR]

Background: Adverse environmental exposure during the prenatal period can lead to diseases in the offspring, including hypertension. Whether or not the hypertensive phenotype can be transgenerationally transmitted is not known.Methods: Pregnant Sprague Dawley rats were intraperitoneally injected with lipopolysaccharide (LPS) on gestation days 6, 8, 10, and 12 to generate the prenatal LPS exposure model. Blood pressure was monitored by both telemetry and tail-cuff method. RNA sequencing was performed to analyze transcriptome alteration in the kidney of the third generation. Tempol and spironolactone were used to test the potential preventative and therapeutic effect of targeting reactive oxygen species and mineralocorticoid receptor signaling, respectively. Molecular biological experiments were performed to illustrate the mechanism of epigenetic and transcription regulation.Results: Prenatal LPS exposure can impair the ability to excrete a salt load and induce hypertension from the first to the third generations, with the fourth and fifth generations, inducing salt-sensitive hypertension. Compared with control pups, the transcriptome in the kidney of the hypertensive third-generation prenatal LPS-exposed offspring have upregulation of the Ras-related C3 botulinum toxin substrate 1 (Rac1) gene and activation of mineralocorticoid receptor signaling. Furthermore, we found that LPS exposure during pregnancy triggered oxidative stress that upregulated KDM3B (histone lysine demethylase 3B) in the oocytes of first-generation female rats, leading to an inheritable low level of H3K9me2 (histone H3 lysine 9 dimethylation), resulting in the transgenerational upregulation of Rac1. Based on these findings, we treated the LPS-exposed pregnant rats with the reactive oxygen species scavenger, tempol, which successfully prevented hypertension in the first-generation offspring and the transgenerational inheritance of hypertension.Conclusions: These findings show that adverse prenatal exposure induces transgenerational hypertension through an epigenetic-regulated mechanism and identify potentially preventive and therapeutic strategies for hypertension. [ABSTRACT FROM AUTHOR]

Background: Genetic variants of coding genes related to blood pressure regulation participate in the pathogenesis of hypertension and determines the response to specific antihypertensive drugs. G protein-coupled receptor kinase 4 (GRK4) and its variants are of great importance in pathogenesis of hypertension. However, little is known about role of GRK4 variants in determine circadian rhythm of blood pressure and response to candesartan in hypertension. The aim of this study was to analyze the correlation of GRK4 variants and circadian rhythm of blood pressure, and to explore their effect on antihypertensive efficiency of candestartan. Methods: In this study, a total of 1239 cases were eligible, completed ambulatory blood pressure monitoring (ABPm) observation and exon sequencing of G protein-coupled receptor kinase 4 (GRK4). ABPm was obtained before and after 4-week treatment of candesartan. Diurnal variation of systolic blood pressure and antihypertensive effect of candesartan were then assessed. Results: Compared to GRK4 wild type (GRK4-WT), patients with GRK4 variants were more likely to be non-dippers (odds ratio (OR) 6.672, 95% confidence interval (CI) 5.124–8.688, P <.001), with GRK4 A142V (OR 5.888, 95% CI 4.332–8.003, P <.001), A486V (OR 7.102, 95% CI 5.334–9.455, P <.001) and GRK4 R65L (OR 3.273, 95% CI 2.271–4.718, P <.001), respectively. Correlation analysis revealed that non-dippers rhythm of blood pressure were associated with GRK4 variants (r =.420, P <.001), with GRK4 A142V (r =.416, P <.001), A486V (r =.465, P <.001) and GRK4 R65L (r =.266, P <.001), respectively. When given 4-week candesartan, patients with GRK4 variants showed better antihypertensive effect as to drop in blood pressure (24 h mSBP, 21.21 ± 4.99 vs 12.34 ± 4.78 mmHg, P <.001) and morning peak (MP-SBP, 16.54 ± 4.37 vs 11.52 ± 4.14 mmHg, P <.001), as well as greater increase in trough to peak ratio (SBP-T/P,.71 ±.07 vs.58 ±.07, P <.001) and smoothness index (SBP-SI, 1.44 ±.16 vs 1.17 ±.11, P <.001) than those with GRK4 WT. Conclusion: This study indicates that hypertensive patients with GRK4 variants are more likely to be non-dippers. What's more, patients with GRK4 variants possess a significantly better antihypertensive response to candesartan than those with GRK4 WT. [ABSTRACT FROM AUTHOR]

Background: Use of an LMA ProSeal™ laryngeal mask airway (P-LMA; Teleflex) with no neuromuscular block is considered a safe alternative to tracheal intubation in short-duration paediatric laparoscopic surgery. However, few studies have evaluated surgical conditions of short-duration paediatric laparoscopic surgery using this anaesthetic technique. We assessed surgical conditions for paediatric laparoscopic inguinal hernia repair using P-LMA with and without neuromuscular block.Methods: Sixty-six patients undergoing laparoscopic inguinal hernia repair were randomised to receive a neuromuscular block (train-of-four 1-2 twitches) using rocuronium or no neuromuscular block with the P-LMA. All operations were performed by the same surgeon who determined the surgical conditions using the Leiden-surgical rating scale (L-SRS). Secondary outcomes included perioperative data, haemodynamics, and adverse events.Results: Neuromuscular block improved surgical conditions compared with no neuromuscular block: mean (standard deviation) L-SRS 4.1 (0.5) vs 3.5 (0.6), respectively (P<0.0001). Mean rocuronium dose in the neuromuscular block group was 12.7 (4.4-29.7) mg or 0.7 (0.6-0.8) mg kg-1. The insufflation Ppeak was higher in the no neuromuscular block group than in the neuromuscular block group: mean (standard deviation) Ppeak 17.9 (1.8) cm H2O vs 16.2 (1.9) cm H2O, respectively (P=0.0004). Fifteen children (45.5%) in the no neuromuscular block group had adverse events during the surgery and anaesthesia vs four children (12.1%) in the neuromuscular block group (P=0.006).Conclusions: Neuromuscular block significantly improved surgical conditions and reduced the incidence of adverse events during surgery and anaesthesia when an LMA Proseal™ was used in short-duration paediatric laparoscopic surgery.Clinical Trial Registration: ChiCTR2000038529. [ABSTRACT FROM AUTHOR]

Background: Surgery results in systemic inflammation, which can affect the central nervous system, leading to changes in mood, emotion, and behavior. Our previous study has shown that compared to midazolam, dexmedetomidine premedication effectively decreased children's postoperative anxiety. Aim: To investigate whether dexmedetomidine infusion before hernia repair alleviates postoperative systemic inflammation in children and whether postoperative anxiety may be associated with postoperative inflammation. Methods: This prospective double‐blind randomized controlled trial was conducted in 120 children scheduled to undergo elective hernia repair. Before anesthesia induction, all children received an intravenous infusion consisted of dexmedetomidine (n = 40; 0.5 µg/g, group D), midazolam (n = 40; 0.08 mg/kg, group M), or normal saline (n = 40; group C). One‐way ANOVA with least significant difference multiple comparison test was used for multigroup comparisons of postoperative plasma levels of inflammatory cytokines and m‐YPAS scores. Spearman rank correlation tests were used for analyzing m‐YPAS scores with postoperative plasma levels of inflammatory cytokines. Results: Plasma levels of tumor necrosis factor‐alpha (7.0 ± 1.6 vs. 8.1 ± 1.6, mean difference [95% CI]: 1.19 [0.26–2.11], p =.008) (pg/ml) and of interleukin‐6 (1.8 ± 1.2 vs. 3.3 ± 1.6, mean difference [95% CI]: 1.49 [0.74–2.25], p <.001) (pg/ml) and neutrophils‐to‐lymphocyte ratio (1.0 ± 0.5 vs. 1.5 ± 0.7, mean difference [95% CI]: 0.48 [0.17–0.78], p <.001) were significantly lower in group D than in group C. Furthermore, compared to group M, group D showed significantly lower plasma tumor necrosis factor‐alpha levels (7.0 ± 1.6 vs. 7.9 ± 1.9, mean difference [95% CI]: 0.96 [0.04–1.88], p =.04) (pg/ml) and interleukin‐6 levels (1.8 ± 1.2 vs. 2.9 ± 1.5, mean difference [95% CI]: 1.06 [0.31–1.81], p =.004) (pg/ml), and neutrophil‐to‐lymphocyte ratio (1.0 ± 0.5 vs. 1.5 ± 0.6, mean difference [95% CI]: 0.42 [0.11–0.72], p =.004). Anxiety scores at postoperative 2 and 4 h in the three groups positively correlated with plasma levels of proinflammatory cytokines. Conclusion: A single preoperative intravenous dexmedetomidine dose in children undergoing same‐day surgery reduces postoperative systemic inflammation. [ABSTRACT FROM AUTHOR]

By index input and standard incidence rate, an epidemic model of tuberculosis repeated infection with inoculation disease was established. The disease-free equilibrium was obtained, and the disease-free e-quilibrium point of the local and global stability was studied. Numerical simulation results further verified the correctness of theoretical results. [ABSTRACT FROM AUTHOR]

Objectives: Au nanoclusters (AuNCs) have been used widely in fluorescence bio‐imaging because of their good fluorescence, small particle size and non‐cytotoxicity. AuNCs are also efficient in computed tomography (CT) imaging. Hence, a dual‐modal imaging probe can be constructed without any complicated modification processes by exploiting the excellent performance of AuNCs. In the present study, AuNCs were enriched with mesoporous silica nanoparticles (MSNs) to obtain enhanced fluorescence/CT dual‐modal imaging, which was capable of acquiring more imaging information for diseases compared with single‐mode imaging. Materials and methods: Biocompatible bovine serum albumin (BSA)‐capped AuNCs were prepared and loaded into amine‐functionalized MSNs to form MSN@AuNCs. BSA‐AuNCs, MSNs, and MSN@AuNCs were characterized by ultraviolet‐visible (UV‐vis) spectra, transmission electron microscopy (TEM), fluorescence spectra, and zeta potential. CT imaging was recorded using micro‐CT scanning. Fluorescence imaging was measured using confocal laser scanning microscopy and flow cytometry. Results: The prepared AuNCs and MSNs possessed good properties as previously reported. The fluorescence intensity and CT value of the AuNCs were enhanced after being enriched with MSNs. The nanoparticles were both non‐cytotoxic. Confocal laser scanning microscopy and flow cytometry indicated that MSN@AuNCs in CAL‐27 cells showed improved fluorescence imaging compared with simple AuNCs at the same concentration. Conclusions: The results revealed that the strategy of enriching AuNCs with MSNs can obtain highly sensitive fluorescence/CT dual‐modal imaging, which indicated the potential of this nanoparticle in the diagnosis and treatment of disease. [ABSTRACT FROM AUTHOR]

Objectives: The mechanisms responsible for the postnatal loss of mammalian cardiac regenerative capacity are not fully elucidated. The aim of the present study is to investigate the role of progesterone in cardiac regeneration and explore underlying mechanism. Materials and Methods: Effect of progesterone on cardiomyocyte proliferation was analysed by immunofluorescent staining. RNA sequencing was performed to screen key target genes of progesterone, and yes‐associated protein (YAP) was knocked down to demonstrate its role in pro‐proliferative effect of progesterone. Effect of progesterone on activity of YAP promoter was measured by luciferase assay and interaction between progesterone receptor and YAP promoter by electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP). Adult mice were subjected to myocardial infarction, and then, effects of progesterone on adult cardiac regeneration were analysed. Results: Progesterone supplementation enhanced cardiomyocyte proliferation in a progesterone receptor‐dependent manner. Progesterone up‐regulated YAP expression and knockdown of YAP by small interfering RNA reduced progesterone‐mediated cardiomyocyte proliferative effect. Progesterone receptor interacted with the YAP promoter, determined by ChIP and EMSA; progesterone increased luciferase activity of YAP promoter and up‐regulated YAP target genes. Progesterone administration also promoted adult cardiomyocyte proliferation and improved cardiac function in myocardial infarction. Conclusion: Our data uncover a role of circulating progesterone withdrawal as a novel mechanism for the postnatal loss of mammalian cardiac regenerative potential. Progesterone promotes both neonatal and adult cardiomyocyte proliferation by up‐regulating YAP expression. [ABSTRACT FROM AUTHOR]

Objective. This study is aimed at investigating the incidence of deep vein thrombosis (DVT) in the uninjured limb during hospitalization and 1 month after surgery in patients with lower extremity fractures. Methods. We collected the clinical data of patients with lower extremity fractures in Xi'an Honghui Hospital. Doppler ultrasonography was used to diagnose DVT. According to the results of ultrasonography, the patients were divided into two groups: uninjured limb with DVT group and uninjured limb without DVT group. Results. A total of 494 patients who met all inclusion criteria were included in this study. The incidence rate of DVT in the uninjured limb was 19.84% and 18.83% during hospitalization and 1 month after surgery, respectively. Age (OR = 1.035 , 95% CI: 1.013–1.059; P = 0.002) and D-dimer level 1 day after surgery (OR = 1.065 , 95% CI: 1.030–1.102; P < 0.001) were independent risk factors for DVT during hospitalization. Similarly, age (OR = 1.045 , 95% CI: 1.021–1.070; P < 0.001) and D-dimer level 1 day after surgery (OR = 1.048 , 95% CI: 1.014–1.083; P = 0.006) were independent risk factors for DVT 1 month after surgery. During hospitalization and 1 month after surgery, 15.79% and 12.35% of patients had double lower limb thrombosis and 4.04% and 6.48% of patients had DVT in the uninjured limb only, respectively. Conclusion. The actual incidence of DVT in the uninjured limb in patients with lower extremity fractures cannot be ignored despite the use of anticoagulants for prevention or treatment during hospitalization. We should also be aware of DVT in the uninjured limb while focusing on DVT in the injured limb. [ABSTRACT FROM AUTHOR]

A diamine ligand having an electron-pulling oxadiazole ring in its molecular structure was synthesized. Its Cu(I) complex was established using PPh 3 as an auxiliary ligand. Geometric structure, electronic transition and photophysical feature of this Cu(I) complex were reported and discussed in detail. It followed a traditional tetrahedral coordination field and suffered from geometric relaxation badly. Aiming at an effective limitation for this geometric relaxation, this Cu(I) complex was immobilized into a polymer matrix via electrospinning technique. A full comparison between solid sample, solution sample and composite sample suggested that such geometric relaxation was effectively limited by polymer immobilization effect. A detailed analysis indicated that polymer host offered a rigid and protective microenvironment for dopant molecules, limiting their geometric relaxation in excited state. As a consequence, photophysical performance was improved, including emission blue shift, long emissive lifetime and improved photostability. [ABSTRACT FROM AUTHOR]

In this paper, a novel method for extraction of electron mobility in the two-dimensional electron gas (2DEG) under the gate of power HEMTs is presented. Using this method enables the potential impact of the gate metal and the gate voltage on electron mobility in the 2DEG under the gate to be measured without the error due to the resistive regions outside the gate, which are the gate-to-source and gate-to-drain regions. The application of the new method was demonstrated by measurements on fabricated circular HEMTs. [ABSTRACT FROM AUTHOR]

Abstract: Electroluminescence (EL) spectra of blue InGaN/GaN multiple-quantum-well light-emitting diode (LED) have been investigated over a wide range of injection current (0.001–200mA) and at various temperatures (6–300K). Surprisingly, with increasing the injection current the EL peak energy shows an initial blueshift accompanied by a broadening of the EL linewidth at low temperatures (below 30K). This trend differs from the usual photoluminescence (PL) measurement results, which have shown that with increasing the optical excitation power the PL peak energy gave an initial blueshift accompanied by a narrowing of the PL linewidth at low temperatures. The anomalous current behavior of the EL spectra may be attributed to electron leakage results in the failure of Coulomb screening effect and the relative enhancement of the low-energetic localized state filling at low temperatures and low currents. The electron leakage for the LED is further confirmed by both the current dependence of the EL intensity and the temperature dependence of the EL efficiency. [Copyright &y& Elsevier]

Abstract: To investigate the mechanism of the yellow luminescence (YL) in GaN, N-face GaN epitaxial film was prepared by wafer bonding and laser lift off from sapphire substrate. The exposed N-polar surface could be etched with potassium hydroxide aqueous solution. Intriguingly, we observed the yellow-to-band-edge luminescence ratio increased by 3.2 times after KOH etching. Since KOH etching is dislocation selective and changes the surface states of GaN, we associated the outstanding increase of YL to the presence of surface states instead of dislocations. It is further confirmed by X-ray photoelectron spectroscopy studies that the Ga vacancies dominate the YL in GaN. [Copyright &y& Elsevier]

Abstract: In this paper, GaN films were successfully grown on the samples of MOCVD-GaN/Al2O3 (MGA) and MOCVD-GaN/6H-SiC (MGS) by HVPE method. We compare the strain of GaN films grown on the two samples by employing various characterization techniques. The surface morphology of GaN films were characterized by field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). The variations of strain characteristic were also microscopically identified using the Z scan of Raman spectroscopy. The Raman peak (E2) shift indicates that the stress enhanced gradually as a function of increasing the measurement depth. The strain of GaN grown on MGA sample is compressive strain, while on MGS is tensile strain. The stress of GaN films grown on MGA and MGS sample are calculated. The difference in the value of stress between calculation and measurement was interpreted. [Copyright &y& Elsevier]

Abstract: The influence of GaCl carrier gas flow rate on GaN films grown by hydride vapor-phase epitaxy (HVPE) was investigated. The symmetric (0002) and asymmetric (10–12) ω scans were detected to estimate the quality of GaN films. Optical properties were studied by room temperature photoluminescence spectra. Raman spectroscopy was employed to analyze the residual stress in the samples. The surface morphology of the GaN films was investigated by atomic force microscopy (AFM). On the basis of process optimization the optimal GaCl carrier gas flow rate for growth of high quality GaN films in our system was obtained as 1.3L/min. [Copyright &y& Elsevier]

Abstract: The hydride vapor phase epitaxy (HVPE) grown GaN samples were etched by H3PO4, mixed solution of H2SO4 and H3PO4 (HH) and molten eutectic of KOH–NaOH (E), respectively. The etching characteristics and surface morphologies were studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The density of etch pits obtained by E etching under optimum etching condition was around 3.0×108 cm−2, which was consistent with the results obtained by the cathodoluminescence (CL) investigation. Two types of etch pits with different sizes were all revealed on the GaN surface using different etching methods. The large etch pits were formed on screw or mixed dislocations, while small etch pits were formed on edge dislocations. The difference in the size of etch pits was interpreted by Cabrera''s thermodynamic theory. Prolonging etching time, the morphology changes of etch pits were different by using H3PO4, HH and E. The etching rate by H3PO4 etching was the fastest and that by E etching was the slowest. According to these etching results, it could be concluded that E etching was a better method for evaluation of dislocations. [Copyright &y& Elsevier]

• Bending-shear test of steel reinforced fast-growing poplar glulam was carried out. • The failure modes of steel reinforced fast-growing poplar glulam beams with different shear span ratios were flexural failure or interlaminar shear failure. • The steel reinforced fast-growing poplar glulam improved bearing capacity, stiffness and ductility. • Theoretical models were proposed to calculate flexural and shear capacity. A new type of steel reinforced fast-growing poplar glulam beam was proposed to improve the mechanical properties of fast-growing poplar glulam beam in this paper. 8 specimens were tested by a four-point bending method. The test was considered two factors: material properties (fast-growing poplar glulam beam, steel reinforced fast-growing poplar glulam beams) and shear-span ratios (1.5, 2, 2.5, 3, 3.5, 4, 6). Test results showed that: (1) The failure mode of the fast-growing poplar glulam beam was interlaminar shear failure. (2) When shear-span ratio (a/h) was between 3 and 6, the failure modes of the steel reinforced fast-growing poplar glulam beams were flexural failure; when shear-span ratio (a/h) was between 1.5 and 2.5, the failure modes of all steel reinforced fast-growing poplar glulam beams were interlaminar shear failure. (3) Compared with the fast-growing poplar glulam beam, the ductile coefficient, the ultimate load, the ultimate displacement and the initial bending stiffness of the steel reinforced fast-growing poplar glulam beams was increased by 92%, 34.7%, 64.7% and 60.9%, respectively. (4) With the increase of a/h, the ultimate load and the initial bending stiffness of the steel reinforced fast-growing poplar glulam beams decreased gradually, while the ultimate displacement and the ductile coefficient decreased first and then increased. Finally, the theoretical model is respectively proposed to estimate the flexural and shear capacity of the steel reinforced fast-growing poplar glulam beams. [ABSTRACT FROM AUTHOR]

We have investigated temperature-dependent photoluminescence (PL) of green and blue light-emitting InGaN/GaN multiple quantum wells at different excitation powers. Two InGaN-related PL peaks centered at around 2.4 and 2.7 eV are assigned to quasi-quantum dot (QD) emissions (PD) and the InGaN matrix emission (PM), respectively, due to a strong phase separation confirmed by high-resolution transmission electron microscopy. In contrast to the S-shaped temperature-dependent behavior of the PM peak energy, the PD peak energy initially decreased and then increased with increasing temperature up to 300 K, indicating that the carriers within QDs relax to stronger localized states first and then are thermalized to higher levels with increasing temperature. Interestingly, it was found that with increasing temperature both the emission intensities initially increased and then decreased. This behavior was attributed to an increased carrier localization effect and then enhanced non-radiative recombination with increasing temperature; this was consistent with the temperature-related behavior of the emission energy. In addition, the temperature dependence of the intensity ratio of PM to PD further shows that the enhanced thermalization effect of the carriers inside the QDs with increasing temperature, resulted in the significant decrease of PD intensity relative to PM intensity. [ABSTRACT FROM AUTHOR]

Photoluminescence (PL) properties of InGaN/GaN multiple quantum wells are studied. Two InGaN-related peaks are observed in the full PL spectrum and are assigned to the quasi-quantum dots (QDs) (2.42 eV) and the InGaN matrix (2.66 eV), due to a strong phase separation. As the carriers transfer from the matrix down to the QDs, an increase of the QDs-related PL intensity (ID) accompanied by the decrease of the matrix-related PL intensity (IM) results. A slight increase of the total PL intensity is also observed, and is attributed to the QDs providing deep potential levels to suppress the outflow of carriers toward surrounding nonradiative centers. A piezoelectric field resulting from the high indium content inside the QDs is observed, which is speculated from Coulomb screening effect. Additionally, we find that the sublinear dependence of the ID on excitation power (P) is due to the saturation of the QDs states, while the superlinear dependence of the IM on P is simultaneously attributed to the suppression of the carriers transferring from the matrix to the QDs and the saturation of the nonradiative centers in the matrix. [ABSTRACT FROM AUTHOR]