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Aggregate segregation compromises the homogeneity of asphalt pavement, which diminishes the road performance of the asphalt mixture. The segregation behavior and damage mechanism of asphalt mixture are complex. To investigate the mechanical properties and cracking behavior of asphalt mixtures with varying degrees of aggregate segregation, the dense-graded asphalt mixture with the nominal maximum size of 13.2 mm (AC-13) and Open Graded Friction Course with the nominal maximum size of 16.0 mm (OGFC-16) with varying degrees of segregation were designed. Indirect tensile test and the digital image correlation (DIC) technology was employed to analyze the strain distribution and strain evolution at the crack initiation point within the asphalt mixtures. The parameters were also proposed to evaluate the resistance to cracking for the segregated asphalt mixtures at a mesoscopic scale. The results show that increased segregation of coarse aggregates in AC-13 mixtures leads to decreased indirect tensile strength, lower maximum tensile strain along the horizontal direction (E11), and reduced failure displacement. Conversely, segregation of fine aggregates in OGFC-16 mixtures results in increased tensile strength, maximum strain, and failure displacement. Higher amount of coarse aggregates in the asphalt mixture contributes to a more intricate strain distribution and a greater number of strain peaks. Dense-graded mixtures show larger strain concentration zones prior to cracking, while smaller stress concentration zones are observed in open-graded mixtures. The horizontal strain-time curve displays distinct stages of stable growth, rapid growth, and rapid decline. Aggregate segregation results in more intricate crack patterns with larger inclination angles, influenced by the random distribution and shapes of coarse aggregates. Novel indexes such as strain uniformity (P1,2) and strain density during crack development (DW) effectively evaluate mesoscopic cracking resistance of asphalt mixtures. The results offer valuable insights into cracking behavior and improve evaluation methods for the mechanical performance of aggregate-segregated asphalt mixtures.

Understanding soil moisture dynamics is crucial for crop growth. The digital mapping of field soil moisture distribution provides valuable information for agricultural water management. The optical satellite data provides fine scale soil moisture information for a region. However, these data are greatly limited due to cloud contamination and revisit period. Despite the reported beneficial effects of spatiotemporal fusion methods, the accurate estimates of high-resolution soil moisture through spatiotemporal fusion data are still unclear, particularly when using Sentinel-2/3 fusion images. This study introduces a new soil moisture estimation framework integrating spatio-temporal spectral information from Sentinel-2/3 fusion images and machine learning algorithm,and thus provide spatiotemporally continuous soil moisture estimation. The framework includes four fusion methods (ESTARRFM, Fit-FC, FSDAF and STFMF) and four machine learning models (PLSR, SVM, RF and GBRT). The feasibility of the framework was validated in the Hetao Irrigation Area of Inner Mongolia, China. The results showed that the Sentinel-2/3 fused image generated by Fit-FC was visually the closest to the true image, followed by ESTARFM, FSDAF, and STFMF. The spatiotemporal fusion-machine learning estimation framework provided reliable estimation for multi-layer (0 ∼ 20, 20 ∼ 40 and 40 ∼ 60 cm) soil water in the irrigation area. The dense time series of soil water generated by the framework facilitated the detection of irrigation events in the irrigated farmland. Our findings highlighted the effectiveness of Sentinel-2/3 fused images in providing high-resolution continuous daily monitoring of farmland soil water on a large scale. These high spatial–temporal resolution time series are valuable for monitoring crop growth and water resource management, contributing to further expanding the application of satellite remote sensing in precision agriculture.

Abstract The quest for alternatives to Pt as an oxygen reduction electrocatalyst, possessing high activity, stability, and abundant reserves, holds great significance for H2/O2 fuel cells. Recently, metal‐nitrogen‐carbon (M‐N‐C) electrocatalysts have garnered substantial attention as promising substitutes. These electrocatalysts not only exhibit well‐defined structures but also offer the flexibility to adjust the central metal atoms and coordination atoms. It is beneficial in elucidating the active sites during the catalytic process and in the design of highly active electrocatalysts. In this review, the real active site of M‐N‐C electrocatalyst‐driven ORR is investigated in depth by in situ characterization techniques such as X‐ray absorption spectroscopy, Raman spectroscopy, Fourier‐transform infrared spectroscopy. It′s worth noting that the catalytic activity of M‐N‐C electrocatalysts originates from the dynamic evolution of electrocatalyst structure. Subsequently, we review various synthetic strategies, including the wet chemistry method, spatial confinement, and template‐assisted method, aimed at the rational design of M‐N‐C electrocatalysts. Moreover, recent progresses of M‐N‐C electrocatalysts with varying configurations, encompassing single‐atom, and double‐atom electrocatalysts are discussed, Finally, summary and perspectives on the development of M‐N‐C are provided.

The crystal and electronic structures determine a material's physical and chemical properties. Here, using particle swarm optimization method and first-principles calculations, we conducted a systematically investigation on the ordered CuxBey alloys. Two novel stable phase CuxBey (P4¯m2-CuBe3, and I4/mmm-Cu2Be) and five novel metastable CuxBey alloys (F4¯3m-CuBe5, P21/m-CuBe4, P4/mmm-Cu3Be, P4/mmm-Cu4Be, and P4/mmm-Cu5Be) are predicted for the first time. The primary alloying form of ordered CuxBey alloys is the substitution of certain Be atoms for some Cu atoms in the FCC-Cu according to structural study. Obvious valence electrons transfer from Be to Cu and the lattice interstice are observed, which leads to Cu exhibiting negative valence state in CuxBey and Be-rich CuxBey acting as zero-dimensional electrides. Furthermore, these Be-rich CuxBey have good structural stability due to the interaction between interstitial anionic electrons and Be atoms in the Be-tetrahedron. These findings help us in the design and application of CuxBey alloys and related materials.

Epitaxial heterostructures, in particular those 2D vertical heterostructures with close face-to-face contact, are appealing candidates for photocatalytic CO2 reduction. Usually, precise control of the growth rate and a seed nanosheet having a small lattice mismatch with the overlayer is essential for the realization of epitaxial growth. Here we present a CO2-initiated solution-phase epitaxial growth strategy to directly fabricate 2D facet-coupled vertical heterostructures without a seed-layer assistant, in which supercritical CO2 liquid can not only manipulate the nucleation and growth of BiOIO3 to match with the epitaxial growth of the Bi2O2CO3 layer, but also provide better wetting conditions to minimize the interfacial energy, thus facilitating the 2D layer-by-layer growth. The obtained heterostructures exhibit the highest CO2-to-CO conversion rate of 224.71 µmol g−1 h−1 in pure water. These findings open up a new platform for highly controlled epitaxial growth of heterostructures.

The chemical engineering of natural extracts has emerged as an effective strategy for the production of diverse libraries of chemicals, making it integral to drug discovery. A chemical engineering strategy based on the epoxidation and ring-opening reactions was used to prepare diversity-enhanced extracts of Chaetomium madrasense 375. Eleven unnatural cytochalasan derivatives (1–11) with unique functional groups, such as amine and isoxazole, were isolated and characterized from these chemically engineered extracts of C. madrasense 375. The identification of these new structures was accomplished through comprehensive spectroscopic analysis, supplemented by synthetic considerations. Notably, compounds 5 and 13–16 displayed potent phytotoxic effects on Arabidopsis thaliana, while compounds 1, 2, 5, 10, and 12 demonstrated inhibitory activities on LPS-induced NO production in RAW264.7 cells. Among them, compound 1 was found to be able to inhibit the upregulated expression of the inducible nitric oxide synthase (iNOS) protein induced by LPS, while also decreasing the production of pro-inflammatory cytokines (IL-6) and influencing the phosphorylation of p38, ERK1/2, and JNK at 100 μM. Our findings demonstrate that the chemical engineering of natural product extracts can be an efficient technique for the generation of novel bioactive molecules.

The lack of highly efficient, inexpensive catalysts severely hinders the large‐scale application of electrochemical energy conversion technologies (e.g., electrochemical hydrogen evolution reaction (HER) for hydrogen production, metal–air batteries (Cathode: oxygen reduction reaction (ORR))). As a new class of nanomaterials with a high ratio of surface atoms and tunable composition and electronic structure, metal nanocluster (NCs) are promising candidates as catalysts. Herein, a novel catalyst using S,N‐doped carbon matrix (NSCSs) is synthesized to efficiently stabilize high density and ultra‐uniform ruthenium (Ru) nanoclusters (Ru@NSCSs) by small‐molecule self‐assembly pyrolysis approach. The obtained Ru@NSCSs catalyst exhibits outstanding HER activity in all pH conditions (especially with a low overpotential of 5 mV at a current density of 10 mA cm−2 in 1 m KOH) and excellent ORR performance (half‐wave potential (E 1/2) of 0.854 V in 0.1 m KOH). Based on the experimental investigations and theoretical calculations, it is discovered that the S‐atom can modulate the electronic structure and optimization of redox states on the surficial sites of Ru NCs during the ORR process. This work provides a feasible strategy for understanding and regulating the metal–support interface of ultra‐uniform nanoclusters catalysts.

Abstract Maladaptive fear memory processing after a traumatic event is a major contributor to the development of the comorbidities related to posttraumatic stress disorder (PTSD). An intervention to normalize this process could be a first-line treatment to prevent PTSD development. However, little progress has been made in identifying interventions that can prevent trauma survivors from developing PTSD. A treatment that could help trauma survivors cope with traumatic memories and decrease the prevalence of PTSD is thus in high demand. This study was designed to investigate the potential beneficial effects of early photobiomodulation (PBM) interventions to prevent PTSD-like comorbidities in animals. PTSD-like comorbidities in rats were induced by an underwater trauma (UWT) procedure, followed by multiple swimming sessions on later days for memory recall. Immediately after UWT and swimming, rats were restrained with or without PBM treatment (808 nm, 25 mW/cm2, 3 J/day). PTSD-like commodities, such as anxiety-like behavior, depression-like behavior, and cognitive dysfunction, were reproduced in UWT-rats. These comorbidities, however, could be prevented by early PBM interventions. By measuring the expression of immediate early genes (IEGs) as neuronal activity markers, we found that PBM treatment differentially regulated Arc and c-fos expression in the hippocampus and amygdala, two PTSD-related brain regions. Additionally, PBM boosted ATP production and regulated protein expression in the hippocampus following stress. Our results demonstrate that PBM can modulate brain activity in response to traumatic and stressful events and that early PBM intervention can prevent the occurrence of PTSD-like comorbidities in rats.

Abstract Interfacial engineering is a powerful method to improve the bifunctional electrocatalytic performance of pure phase catalysts. While it is expected to further optimize the electronic configuration of heterojunctions to boost the reaction kinetics in hydrogen/oxygen evolution reaction (HER/OER), but remains a challenge. Herein, a novel in situ hybrid heterojunction strategy is developed to construct 2D porous Co‐doped Ni/Ni3N heterostructure nanosheets (Co–Ni/Ni3N) by pyrolysis of partially cobalt substituted nickel‐zeolitic imidazolate framework (CoNi‐ZIF) nanosheets under NH3 atmosphere. A combined experimental and theoretical studies manifest that the hybrid heterostructures can display regulative electronic states and downshift d‐band center from the Fermi level, as well as optimize the adsorption energy of reaction intermediates, thus reducing the thermodynamic energy barriers and accelerating the catalytic kinetics. Consequently, benefitting from the optimized electronic configuration, hierarchical hollow nanosheets architecture, and abundant doped heterojunctions, the hybrid Co–Ni/Ni3N heterostructure catalyst exhibits efficient catalytic activity for both HER (60 mV) and OER (322 mV) at 10 mA cm−2 in alkaline media, which is 105 and 47 mV lower than that of pure Ni3N, respectively. The electrochemically active surface area of Co–Ni/Ni3N is two times higher than that of Ni3N. Furthermore, the coupled practical water electrolyzer requires a low voltage of 1.575 V to reach 10 mA cm−2, and it can be driven by a 1.5 V battery. This work highlights the interface engineering guidance for the rational establishment of hybrid interfaces by electronic modulation of interfacial effect for alkaline water splitting.

Abstract Background Current there are different screws fixation methods used for fixation of the talar neck fracture. However, the best method of screws internal fixation is still controversial. Few relevant studies have focused on this issue, especially by finite element analysis. The purpose of this study was to explore the mechanical stability of dual screws internal fixation methods with different approaches and the best biomechanical environment of the fracture section, so as to provide reliable mechanical evidence for the selection of clinical internal fixation. Methods The computed tomography (CT) image of the healthy adult male ankle joint was used for three-dimensional reconstruction of the ankle model. Talus neck fracture and screws were constructed by computer-aided design (CAD). Then, 3D model of talar neck fracture which fixed with antero-posterior (AP) parallel dual screws, antero-posterior (AP) cross dual screws, postero-anterior (PA) parallel dual screws, and postero-anterior (PA) cross dual screws were simulated. Finally, under the condition of 2400N vertical load, finite element analysis (FEA) were carried out to compare the outcome of the four different internal fixation methods. The results of Von Mises stress, displacement of four groups which contain talus fracture fragments and screws internal fixations were analyzed. Results Compared with the other three groups, postero-anterior (PA) parallel dual screws had better results in the stress peak, stress distribution, and displacement of talus and internal fixation. Conclusions To sum up, the Von Mises stress of fracture section was the smallest, the stress distribution of screws were the most scattered, and the peak value was the smallest in posterior to anterior parallel double screws fixation, which was obviously better than that in the other three groups. When using screws internal fixation, the method of posterior to anterior screws fixation is better than that of anterior to posterior screws fixation, and the peak value and stress distribution of parallel double screws fixation is better than that of cross double screws fixation. Thus, for the talar neck fracture, the use of posterior to anterior parallel double screws fixation is recommended in clinical surgery.

Abstract Defect engineering is a desired manner to promote the performance of electrodes. Herein, by employing the boron atom substitution and carbon–boron vacancy–vacancy pairs in graphene, a defect‐induced two‐dimensional new phase, popC5B, is formed. The evidences indicate that it has dynamic, thermal, and mechanical stabilities. When used as anodes in Li/Na‐ion batteries, it possesses high theoretical specific capacities of 1891/1135 mAh/g. The high capacity is attributed to the synergy effect of various defect engineering and defect‐induced phase transition that lead to the charge delocalization in popC5B and promote the electron transfer between metal ions and popC5B. This study demonstrates that the synergy effect of various kinds of defects could be an effective approach to acquire high performance electrodes in batteries.

In this study, a quantitative method for the content determination of rutin, 5-O-coumaroylquinic acid methyl ester, chlorogenic acid butyl ester, and kaempferol in Amygdalus persica L. flowers during different harvest periods was established to investigate its various rules and determine the optimal harvesting period. The determination was performed on the XTERRA MS C18 column with a mobile phase consisting of 0.1% formic acid aqueous solution and acetonitrile (gradient elution) at a flow rate of 1.0 mL/min. In combination with other validation data, including precision, stability, and recovery tests, this method demonstrated good reliability and sensitivity. The results showed that the contents of rutin, 5-O-coumaroylquinic acid methyl ester, chlorogenic acid butyl ester, and kaempferol in A. persica flowers during different harvest periods were quite different, and the content in samples at the early blooming stage was the highest. The method is simple, accurate, and rapid for determining the contents of four active ingredients in A. persica flowers.

The coordinated control method of Unmanned Electric Formula Racing (UEFC) was studied to improve the handling stability of UEFC. The UEFC’s mechanical structure, which is based on the driving system and transmission system, was designed. In accordance with mechanical structure of the designed racing car, a seven-degree of freedom mathematical model of the UEFC was established. In accordance with the built mathematical model of racing car, the lateral controller of racing car was designed by using a fuzzy neural network method. The longitudinal controller of the racing car was designed by using the method of incremental PID control, and the coordination controller of the racing car was designed by combining the lateral controller and the longitudinal controller so as to realize the lateral and longitudinal coordination control of the UEFC. The experimental results showed that the output parameters such as yaw rate, vehicle speed and heading angle were slightly different from the expected output. It was confirmed that the research method can enhance the handling stability of the UEFC.

Amyloid-β protein (Aβ) is an important biomarker and plays a key role in the early stage of Alzheimer’s disease (AD). Here, an ultrasensitive photoelectrochemical (PEC) sensor based on ZnO@polydopamine/Au nanocomposites was constructed for quantitative detection of Aβ. In this sensing system, the ZnO nanorod array decorated with PDA films and gold nanoparticles (Au NPs) have excellent visible-light activity. The PDA film was used as a sensitizer for charge separation, and it also was used for antibody binding. Moreover, Au NPs were loaded on the surface of PDA film by in situ deposition, which further improved the charge transfer efficiency and the PEC activity in visible light due to the localized surface plasmon resonance effect of Au NPs. Therefore, in ZnO@polydopamine/Au nanocomposites, a significantly enhanced photocurrent response was obtained on this photoelectrode, which provides a good and reliable signal for early detection of AD. Under the optimized conditions, the PEC immunosensor displayed a wide linear range from 1 pg/mL to 100 ng/mL and a low detection limit of 0.26 pg/mL. In addition, this PEC immunosensor also presented good selectivity, stability, and reproducibility. This work may provide a promising point-of-care testing method toward advanced PEC immunoassays for AD biomarkers.

Abstract Background The efficacy and safety of multikinase inhibitor anlotinib have been confirmed in the treatment of advanced non-small cell lung cancer (NSCLC). However, the direct functional mechanisms of tumor lethality mediated by anlotinib were not fully elucidated, and the underlying mechanisms related to resistance remain largely elusive. Methods Cell viability, colony formation, apoptosis and tumor growth assays were performed to examine the effect of anlotinib on lung cancer cells in vitro and in vivo. The punctate patterns of LC3-I/II were detected by confocal microscopy. HUVECs motility was detected using Transwell and scratch wound-healing assay. To visualize the microvessels, tubular formation assay was performed. The expression of LC3-I/II and beclin-1 and the changes of JAK2/STAT3/VEGFA pathway were detected by western blotting. The VEGFA levels in tumor supernatant were measured by ELISA. Results Anlotinib treatment decreased cell viability and induced apoptosis in Calu-1 and A549 cells. Moreover, anlotinib induced human lung cancer cell autophagy in a dose- and time-dependent manner. Blocking autophagy enhanced the cytotoxicity and anti-angiogenic ability of anlotinib as evidenced by HUVECs migration, invasion, and tubular formation assay. Co-administration of anlotinib and chloroquine (CQ) further reduced VEGFA level in the tumor supernatant, compared with that of anlotinib or CQ treatment alone. When autophagy was induced by rapamycin, the JAK2/STAT3 pathway was activated and VEGFA was elevated, which was attenuated after deactivating STAT3 by S3I-201. Further in vivo studies showed that anlotinib inhibited tumor growth, induced autophagy and suppressed JAK2/STAT3/VEGFA pathway, and CQ enhanced this effect. Conclusion Anlotinib induced apoptosis and protective autophagy in human lung cancer cell lines. Autophagy inhibition further enhanced the cytotoxic effects of anlotinib, and potentiated the anti-angiogenic property of anlotinib through JAK2/STAT3/VEGFA signaling.

“Diversity-enhanced extracts” is an effective method of producing chemical libraries for the purpose of drug discovery. Three rare new cytochalasan derivative chaetoglobosins B1-B3 (1–3) were obtained from chemically engineered crude broth extracts of Chaetomium madrasense 375 prepared by reacting with hydrazine monohydrate and four known metabolite chaetoglobosins (4–7) were also identified from the fungus. The structures were identified by NMR and MS analysis and electronic circular dichroism simulation. In addition, the antiproliferative activities of these compounds were also evaluated, and the drug-resistant activities of cytochalasans were evaluated for the first time. Compound 6 possessed potent activity against four human cancer cells (A549, HCC827, SW620, and MDA-MB-231), and two drug-resistant HCC827 cells (Gefitinib-resistant, Osimertinib-resistant) compared with the positive controls.

Amygdalus persica L., belongs to Rosaceae family, and its flowers are used as medicine and food. n-Butanol extract of A. persica flowers were isolated and purified with various column chromatographies, and the fourteen compounds, chlorogenic acid butyl ester (1), rutin (2), protocatechuic acid (3), caffeic acid (4), 5-O-coumarroylquinic acid methyl ester (5), kaempferol-3-O-neohesperidoside (6), quercetin-3-O-β-D-glucoside (7), 3,5-dicaffeoylquinic acid (8), quercetin-3-O-α-L-rhamnoside (9), 5-O-coumaroylquinic acid (10), kaempferol-3-O-α-L-rhamnoside (11), kaempferol-3-O-β-D-galactoside (12), D-glucitol (13), and multiflorin A (14), were identified by spectroscopic data and physical data. All the compounds except compound 2 were identified from A. persica flowers for the first time. The compounds were investigated for their coagulation activity by activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), and bibrinogen (FIB) in vitro. The results of coagulation activity showed that rutin (2), caffeic acid (4), kaempferol-3-O-neohesperidoside (6), kaempferol-3-O-α-L-rhamnoside (11), and kaempferol-3-O-β-D-galactoside (12) exhibited significant procoagulant activity, while chlorogenic acid butyl ester (1) possessed anticoagulant activity in vitro.

The etiology of Posner-Schlossman syndrome (PSS) remains unknown. The association of human leukocyte antigens (HLA) allelic diversity with PSS has been poorly investigated. To evaluate the association of allelic polymorphisms of class I HLA-A, -B and -C and class II HLA-DRB1 and -DQB1 with PSS, 100 unrelated patients with PSS and 128 age- and ethnically matched control subjects were recruited from a southern Chinese Han population. Polymorphisms in exons 2-4 for HLA-A, -B, -C loci, exon 2 for HLA-DRB1 and exons 2,3 for HLA-DQB1 were analyzed for association with PSS at allele and haplotype levels. The allele frequency of HLA-C*1402 in PSS patients was significantly higher than that in controls (P = 0.002, OR = 4.12). This association survived the Bonferroni correction (Pc = 0.04). The allele frequency of HLA-B*1301 in PSS patients was lower than that in the control group (P = 0.003, OR = 0.21), although this association did not survive the Bonferroni correction (Pc = 0.16). In PSS patients, the haplotype frequencies of HLA-A*1101~C*1402 and B*5101~C*1402 were higher than that in controls (P = 0.03, OR = 4.44; P = 0.02, OR = 3.20; respectively), while the HLA-B*1301~C*0304 was lower than that in controls (P = 0.007, OR = 0.23), although these associations did not survive the Bonferroni correction (Pc > 0.16). This study for the first time demonstrated that polymorphisms at the HLA-B and HLA-C loci were nominally associated with PSS in the southern Chinese Han population. Our results suggest that HLA-C*1402, A*1101~C*1402 and B*5101~C*1402 might be risk factors for PSS, whereas HLA-B*1301 plus B*1301~C*0304 might be protective factors against PSS, but even larger datasets are required to confirm these findings. Findings from this study provide valuable new clues for investigating the mechanisms and development of new diagnosis and treatment for PSS.

Nonstructural protein 3 (NS3) of hepatitis C virus (HCV), codes for protease and helicase carrying NTPase enzymatic activities, plays a crucial role in viral replication and an ideal target for diagnosis, antiviral therapy and vaccine development. In this study, monoclonal antibodies (mAbs) to NS3 helicase were characterized by epitope mapping and biological function test. A total of 29 monoclonal antibodies were produced to the truncated NS3 helicase of HCV-1b (T1b-rNS3, aa1192-1459). Six mAbs recognized 8/29 16mer peptides, which contributed to identify 5 linear and 1 discontinuous putative epitope sequences. Seven mAbs reacted with HCV-2a JFH-1 infected Huh-7.5.1 cells by immunofluorescent staining, of which 2E12 and 3E5 strongly bound to the exposed linear epitope (1231)PTGSGKSTK(1239) (EP05) or core motif (1373)IPFYGKAI(1380) (EP21), respectively. Five other mAbs recognized semi-conformational or conformational epitopes of HCV helicase. MAb 2E12 binds to epitope EP05 at the ATP binding site of motif I in domain 1, while mAb 3E5 reacts with epitope EP21 close to helicase nucleotide binding region of domain 2. Epitope EP05 is totally conserved and EP21 highly conserved across HCV genotypes. These two epitope peptides reacted strongly with 59-79% chronic and weakly with 30-58% resolved HCV infected blood donors, suggesting that these epitopes were dominant in HCV infection. MAb 2E12 inhibited 50% of unwinding activity of NS3 helicase in vitro. Novel monoclonal antibodies recognize highly conserved epitopes at crucial functional sites within NS3 helicase, which may become important antibodies for diagnosis and antiviral therapy in chronic HCV infection.

The water-soluble CdSe nanocrystal/poly(allylamine) clusters are prepared using 3-amino-1-propanol as a compatibilizing agent. It is found that decreasing the pH value below 12 resulted in dramatic reduction in PL brightness, despite cluster densification due to partial ionization and dissolution of the amine-based NC surface-capping agents.

A controlled O2-assisted etching of CdSe nanaocrystals (NCs) by heating them at 80 degrees Celsius in 10/1 [3-amino-1-propanol (APOL)]/water mixtures are described. The photoluminescence quantum yield (QY) maxima and fwhm emission minima in the plateau regions of bottleneck type of etching could provide a possible venue for reconstruction and surface modification of CdSe NCs.

The need for physicians and technical consultants specialized in transfusion medicine is urgent in China, as there are 20 000 hospitals and 500 blood centers in need of staff with this expertise. The progress made in transfusion medicine as a specialty has been relatively slow in China. Current Chinese medical education and service systems have not developed transfusion medicine as a stand-alone medical specialty. Most physicians receive only minimal training in transfusion medicine in medical school. This training is usually integrated into surgical training and addresses the most common technologies. In 2008, a 5-year bachelor's diploma program in transfusion medicine was established as an undergraduate specialty in Southern Medical University, Guangzhou, China. This article intends to summarize the 8 years of experience educating undergraduates in the specialty of transfusion medicine. [ABSTRACT FROM AUTHOR]

Background: Neonatal hepatitis B vaccination program at birth has been implemented nationwide since 1992 in China. However, current HBV prevalence status in blood donors has not been entirely examined, which may impact HBV safety in blood donations as the vaccinees over 18 years old progressively become the majority population of blood donors.Methods: In this study, 569,145 blood donors were screened for HBsAg by rapid tests and enzyme immunoassays, among them 475,538 blood samples with negative HBsAg were further screened for HBV DNA by nucleic acid testing between 2005 and 2014 at Shenzhen blood center.Results: An overall 2.3 % HBsAg prevalence was found in the blood donor population during the past 10 years (2.86 % in 2005, 1.76 % in 2010, and 2.79 % in 2014, respectively). HBsAg seroconversion occurred in 0.37 % of repeat-donors. When stratified by age, the prevalence of HBsAg was found significantly higher in younger donors age 18-25 years (2.73 %) than in those 26-35 years (2.13 %), 36-45 years (2.03 %) and 46-58 years (1.71 %) (P < 0.001), unexpectedly suggesting that younger donors remained at risk of chronic HBV infection. Assuming that donors aged 18-22 born before or after 1992 were non-vaccinated and vaccinated, respectively, HBsAg prevalence was higher in first-time donors born ≥1992 (3.9 %) than prior to 1992 (3.5 %, P = 0.005). The incidence of HBV infection in the 5-year period examined was significantly lower in repeat-donors born ≥1992 (0.27 %) than prior to 1992 (0.6 %, P = 0.008). The yield of HBV DNA+/HBsAg- donors was 1:3,302, including 1:4,486 occult infections and 1:43,231 window period infections.Conclusion: Young blood donors born after implementation of universal HBV vaccination in China presented higher prevalence of HBsAg but lower incidence of HBsAg seroconversion than older, presumed unvaccinated, donors. HBV vaccine boosting for adolescents at 15-17 years old prior to reaching blood donor age might help improve blood safety. [ABSTRACT FROM AUTHOR]

Understanding the effect of defects on mechanical responses and failure behaviors of a graphene membrane is important for its applications. As examples, in this paper, a family of graphene with various 5-8-5 defects are designed and their mechanical responses are investigated by employing molecular dynamics simulations. The dependence of fracture strength and strain as well as Young's moduli on the nearest neighbor distance and defect types is examined. By introducing the 5-8-5 defects into graphene, the fracture strength and strain become smaller. However, the Young's moduli of DL (Linear arrangement of repeat unit 5-8-5 defect along zigzag-direction of graphene), DS (a Slope angle between repeat unit 5-8-5 defect and zigzag direction of graphene) and DZ (Zigzag-like 5-8-5 defects) defects in the zigzag direction become larger than those in the pristine graphene in the same direction. A maximum increase of 11.8% of Young's modulus is obtained. Furthermore, the brittle cracking mechanism is proposed for the graphene with 5-8-5 defects. The present work may provide insights in controlling the mechanical properties by preparing defects in the graphene, and give a full picture for the applications of graphene with defects in flexible electronics and nanodevices. [ABSTRACT FROM AUTHOR]

Insulin resistance is common in critically ill patients and seriously affects their prognosis. The anesthetic propofol (2,6-diisopropylphenol) has been shown to cause insulin resistance in rats; however, the specific mechanism underlying this phenomenon remains unknown. Thus, the aim of the present study was to determine the molecular mechanism through which propofol influences insulin resistance in the liver. The current study assessed the effects of propofol on the phosphorylation level of key enzymes involved in the insulin signaling pathway, as well as the glycogen content in primary mouse hepatocytes. Propofol administration was demonstrated to considerably reduce the phosphorylation levels of Akt (Ser473) and glycogen synthase kinase (GSK)-3β (Ser9) in the primary mouse hepatocytes. In addition, propofol was shown to downregulate the phosphoinositide 3-kinase (PI3K)/Akt/GSK-3β signaling pathway and inhibit glycogen synthesis in hepatocytes. Thus, the present results indicated that propofol induced insulin resistance in primary mouse hepatocytes. Notably, pretreatment with propofol in tumor necrosis factor (TNF)-α-induced primary mouse hepatocytes with insulin resistance was demonstrated to alleviate the inhibitory effects of TNF-α on the PI3K/Akt/GSK-3β signaling pathway and glycogen synthesis. These results indicated that propofol exerts a protective effect against insulin resistance in primary mouse hepatocytes induced by TNF-α, indicating that propofol therapy may be clinically feasible to alleviate insulin resistance in critically ill patients. [ABSTRACT FROM AUTHOR]

The neutral and anionic ConCN (n = 1-5) clusters were investigated using density functional calculations. The most stable structures of neutral and anionic ConCN (n = 1-5) clusters have been identified. In these structures, the CN radical retains its integrity as a structural unit. For anionic ConCN- (n = 1-5) and neutral ConCN (n = 1-2) clusters, the CN prefers to be adsorbed on the top sites of Con clusters via the C terminal, forming a linear or quasi-linear N-C-Co structure. For neutral ConCN (n = 3-5) clusters, the CN is adsorbed on the bridge sites of Con (n = 3-5) by both C and N atoms. Compared to the free CN radical calculated at the same level, the C-N stretching frequencies of neutral ConCN (n = 3-5) are red-shifted while they are blue-shifted for neutral ConCN (n = 1-2). The adiabatic and vertical detachment energies of anionic ConCN- (n = 1-5) clusters are calculated based on density functional calculations. In addition, the most favored dissociation channels of neutral and anionic ConCN (n = 1-5) clusters are determined by calculating the dissociation energies of various possible dissociation pathways. [ABSTRACT FROM AUTHOR]

A new electrochemical voltammetric sensor, Langmuir-Blodgett (LB) film of 25,27-dimethoxy-26-( N-trichloroacetyl)carbamoyloxy- p-tert-butylcalix[4]arene (DCA) modified GCE (LB-GCE), was designed and successfully used for recognition and determination of trace amounts of Ag in water. Under the optimum experimental conditions, the lowest detectable concentration of Ag reached 1 × 10 mol L. Moreover, LB-GCE exhibited a well-defined response relating to the Ag with good sensitivity, selectivity, reproducibility, and long stability. The recognizing mechanism of LB-GCE for silver ion in aqueous solution was also discussed. The results show that the size of calixarene cavity may be the predominate factor affecting recognition of calixarene for silver ions. A new electrochemical voltammetric sensor, based on a DCA LB film modified electrode, was fabricated and used for Ag determination. The result indicated that such materials with corresponding size of cavity may have an interaction effect with metal ions and could be used for the determination of metal ions. [ABSTRACT FROM AUTHOR]

Phase-pure bismuth oxide (Bi2O3) nanorods with an average diameter of 75 nm were fabricated through a facile hydrothermal method for the first time. The UV-vis spectra suggest that the band gap of Bi2O3 nanorods is of a 0.03 eV red shift than the bulky Bi2O3. PL spectra demonstrate that the Bi2O3 nanorods show strong room temperature luminescence at 440 nm. Under UV-pulsed illumination, the photocurrent density of the Bi2O3 nanorod photoanode increases obviously with the applied potential, indicating potential applications in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Developing advanced electrochemical electrode materials with excellent performance is critical to their future energy storage devices. Herein, we design and synthesize two-dimensional (2D) porous structure nickel oxide (NiO) nanosheets via a facile and scalable hydrothermal approach, and further heating. The effects of heating time on the electrochemical performances are investigated. The results indicate that the maximum specific capacitance is achieved for NiO nanosheets when heating temperature and time are 300 °C and 3 h, respectively (namely NiO-3). The as-prepared NiO-3 nanosheet are grown uniform on the skeleton of reduced graphene oxide (rGO). The optimum NiO/rGO displays a reversible discharge capacity of 781.7 F g−1 at 1 A g−1, and shows an ultra-long life-span with over 94% capacitance retention after 4000 cycles. The enhanced electrochemical properties for NiO/rGO can be ascribed to a collaborative effect between NiO and rGO, which possess high capacitance storage ability and excellent conductivity, respectively. [ABSTRACT FROM AUTHOR]

We have demonstrated a novel three-dimensional (3D) architecture of a graphene/carbon nanotube (G-CNT) hybrid synthesized at large scale within just 5 s via a simple microwave-heating method without the usage of any other conducting or expanding agent for the first time. The carbon composites obtained consist of evenly grown CNTs with an average diameter of about 15 nm on the surface of graphene nanosheets. The G-CNT hybrid exhibits enhanced electrochemical performance for both aqueous and organic supercapacitor devices. Particularly, the G-CNT electrodes demonstrate an enhanced specific capacitance of 361 F g−1 at a current density of 1.1 A g−1 in an aqueous electrolyte and a volumetric capacitance of 254 F cm−3 in an organic electrolyte. They also display excellent cycle stability with nearly 91.2% of the initial capacitance retained after 10 000 charging-discharging cycles at a current density of 15 A g−1. This demonstrates that the developed composites have potential applications in supercapacitors and other energy storage devices. [ABSTRACT FROM AUTHOR]

Freestanding polyaniline (PANI) nanorods grown in situ on microwave-expanded graphene oxide (MEGO) sheets were prepared through a facile solution method. The morphological characterization indicates that large quantity of free-standing PANI nanorods with average diameter of 50 nm were uniformly deposited onto the double sides of the MEGO nanosheets to form a sandwich structure. The hybrid of PANI/MEGO (GPANI) exhibit high specific surface area and high electrical conductivity, compared with pristine PANI nanorods. When evaluated as electrodes for supercapacitors, the GPANI demonstrate high specific capacitance of 628 F g−1 at a current density of 1.1 A g−1, high-rate performance, and excellent cycle stability compared to individual component. Such excellent electrochemical performance should be attributed to the combined double-layer capacitance and pseudo -capacitance mechanisms from the MEGO sheets and PANI nanorods. [ABSTRACT FROM AUTHOR]

MnO2 nanoplates grown on graphene sheets have been directly synthesized during the graphite oxide (GO) reduction. The synthetic method is efficient, green and controllable with GO reduced and MnO2 nanoplates formed in one step. Compared with conventional methods, this method is easier to implement without using binders or any conductive additives. The as-prepared MnO2 nanoplates and graphene composites (GM) electrodes exhibit enhanced electrochemical performances, including ultrahigh specific capacitance (385Fg-1, at current density of 1Ag-1) and excellent cycling stabilities with 1M Na2SO4 electrolytes. This improvement is due to the tighter contact between graphene sheets and MnO2 nanoplates, and the higher conductive and capacitive characteristics of graphene. [ABSTRACT FROM AUTHOR]