Light-emitting devices based on atomically thin MoSe_(2)

Atomically thin MoSe_(2) layers,as a core member of the transition metal dichalcogenides(TMDs)family,benefit from their appealing properties,including tunable band gaps,high exciton binding energies,and giant oscillator strengths,thus pro-viding an intriguing platform for optoelectronic applications of light-emitting diodes(LEDs),field-effect transistors(FETs),sin-gle-photon emitters(SPEs),and coherent light sources(CLSs).Moreover,these MoSe_(2) layers can realize strong excitonic emis-sion in the near-infrared wavelengths,which can be combined with the silicon-based integration technologies and further encourage the development of the new generation technologies of on-chip optical interconnection,quantum computing,and quantum information processing.Herein,we overview the state-of-the-art applications of light-emitting devices based on two-dimensional MoSe_(2) layers.Firstly,we introduce recent developments in excitonic emission features from atomically thin MoSe_(2) and their dependences on typical physical fields.Next,we focus on the exciton-polaritons and plasmon-exciton polaritons in MoSe_(2) coupled to the diverse forms of optical microcavities.Then,we highlight the promising applications of LEDs,SPEs,and CLSs based on MoSe_(2) and their heterostructures.Finally,we summarize the challenges and opportunities for high-quality emis-sion of MoSe_(2) and high-performance light-emitting devices.

Red light induces salicylic acid accumulation by activating CaHY5 to enhance pepper resistance against Phytophthora capsici

Pepper(Capsicum annuum L.)is frequently challenged by various pathogens,among which Phytophthora capsici is the most devastating to pepper production.Red light signal acts as a positive induction of plant resistance against multiple pathogens.However,little is known about how the red light signal affects pepper resistance to P.capsici infection(PCI).Here,we report that red light regulates salicylic acid(SA)accumulation by activating elongated hypocotyl5(CaHY5),a basic leucine zipper(bZIP)transcription factor,thereby decreasing pepper susceptibility to PCI.Exogenous SA treatment reduced pepper susceptibility to PCI,while silencing of CaPHYB(a red light photoreceptor)increased its susceptibility.PCI significantly induced CaHY5 expression,and silencing of CaHY5 reduced SA accumulation,accompanied by decreases in the expression levels of phenylalanine ammonia-lyase 3(CaPAL3),CaPAL7,pathogenesis-related 1(CaPR1),and CaPR1L,which finally resulted in higher susceptibility of pepper to PCI.Moreover,CaHY5 was found to activate the expression of CaPAL3 and CaPAL7,which are essential for SA biosynthesis,by directly binding to their promoters.Further analysis revealed that exogenous SA treatment could restore the resistance of CaHY5-silenced pepper plants to PCI.Collectively,this study reveals a critical mechanism through which red light induces SA accumulation by regulating CaHY5-mediated CaPAL3 and CaPAL7 expression,leading to enhanced resistance to PCI.Moreover,red light-induced CaHY5 regulates pepper resistance to PCI,which may have implications for PCI control in protected vegetable production.

多巴胺对碳纤维增强聚苯硫醚复合材料界面性能的影响

碳纤维增强聚苯硫醚复合材料(CF/PPS)因其具有优异的综合性能被广泛关注,但实际应用中发现碳纤维与聚苯硫醚的界面结合并不理想,因此,改善CF/PPS界面结合强度来提升其宏观力学性能就有着深远的理论意义和应用价值。文中基于微球脱粘技术,将具有优良黏附性的多巴胺水溶液作为界面改性剂,对纤维进行表面改性,采用微球脱粘实验和宏观拉伸等实验测试探究了不同多巴胺浓度对CF/PPS界面性能的影响。结果表明,当多巴胺浓度为2 g/L时,聚多巴胺在碳纤维表面均匀黏附,形成较好的微纳结构,涂覆效果最佳,表观界面剪切强度最大为36.09 MPa,较未改性前增加13.50%;PDA-CF2/PPS拉伸试样的断面呈现凹凸不平的形态,拔出的碳纤维上残留树脂基体最多,具有良好的界面改性效果。

In-situ measurement via the flow-through method and numerical simulations for radon exhalation during measurements of the radon exhalation rate

Small-scale measurements of the radon exhalation rate using the flow-through and closed-loop methods were conducted on the surface of a uranium tailing pond to better understand the differences between the two methods.An abnormal radon exhalation behavior was observed,leading to computational fluid dynamics(CFD)-based simulations in which dynamic radon migration in a porous medium and accumulation chamber was considered.Based on the in-situ experimental and numerical simulation results,variations in the radon exhalation rate subject to permeability,flow rate,and insertion depth were quantified and analyzed.The in-situ radon exhalation rates measured using the flow-through method were higher than those measured using the closed-loop method,which could be explained by the negative pressure difference between the inside and outside of the chamber during the measurements.The consistency of the variations in the radon exhalation rate between the experiments and simulations suggests the reliability of CFD-based techniques in obtaining the dynamic evolution of transient radon exhalation rates for diffusion and convection at the porous medium-air interface.The synergistic effects of the three factors(insertion depth,flow rate,and permeability)on the negative pressure difference and measured exhalation rate were quantified,and multivariate regression models were established,with positive correlations in most cases;the exhalation rate decreased with increasing insertion depth at a permeability of 1×10^(−11) m^(2).CFD-based simulations can provide theoretical guidance for improving the flow-through method and thus achieve accurate measurements.

4种肌少症筛查工具在慢性肝病患者中应用的性能比较

目的比较shii评分、 肌少症筛查5项评分量表(Strength, Assistance with Walking, Rise from aChair, Climb Stairs and Falls , SARC-F).肌少症筛查5项评分联合小腿围量表(SARC-F and Calf Circumferen-ce, SARC-CalF)及迷你肌少症风险评估-7条目问卷(Mini Sarcopenia Risk Assessment-7 ,MSRA-7)筛查慢性肝病患者肌少症的相对准确性。方法该前瞻性研究纳人366例慢性肝病患者。应用Ishii评分.SARC-F、SARC-CalF和MSRA-7对患者进行筛查。肌少症由临床医生根据亚洲肌少症工作组(AsiaWorkingGroupforSarco-penia,AWGS)2019标准进行诊断,以此为金标准对4种筛查工具的性能进行比较。结果基于AWGS2019标准,本组慢性肝病患者的肌少症患病率为17.5%。Ishii评分、SARC-F .SARC-CalF和MSRA-7的受试者工作特征(receiver operating characteristic, ROC)曲线下面积(敏感度,特异度)分别为0.820(8594% ,78.15%)、0.528(6.25% , 99.34%) 0.642(45.31% , 83.1 1%).0.552(87.50% ,22.85%)。根据ROC曲线下面积、决策曲线以及校准曲线分析结果,Ishi评分筛查馒性肝病患者肌少症的性能优于其他3个工具(P<0.0001)。结论Ishii评分比SARC-F.SARC-CalF和MSRA-7更适合用于筛查馒性肝病患者的肌少症。护士在临床工作中可应用Ishii评分对慢性肝病患者进行肌少症筛查,早期发现肌少症风险,为进一步诊断肌少症提供依据。

Improving the performance of arylamine-based hole transporting materials in perovskite solar cells： Extending π-conjugation length or increasing the number of side groups？

In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups compared with reference compound on the photophysical, electrochemical, hole mobility properties and performance in perovskite solar cells were further studied. It is noted that these two kinds of molecular modifications can significantly lower the HOMO level and improve the hole mobility, thus improving the hole injection from valence band of perovskite. On the other hand, the compound with more side groups showed higher hole injection efficiency due to lower HOMO level and higher hole mo- bility compared with the compound with extending π-conjugation length. The perovskite solar cells with the modified molecules as hole transporting materials showed a higher efficiency of 15.40% and 16.95%, respectively, which is better than that of the reference compound （13.18%）. Moreover, the compound with increasing number of side groups based devices showed comparable photovoltaic performance with that of conventional spiro-OMeTAD （16.87%）.

Optimal choice of stapler and digestive tract reconstruction method after distal gastrectomy for gastric cancer:A prospective case–control study

BACKGROUND Gastric cancer is the most common cause of cancer-related deaths,and is classified according to its location in the proximal,middle,or distal stomach.Surgical resection is the primary approach for treating gastric cancer.This prospective study aimed to determine the best reconstruction method after distal gastrectomy for gastric cancer.AIM To explore the efficacy of different staplers and digestive tract reconstruction(DTR)methods after radical gastrectomy and their influence on prognosis.METHODS Eighty-seven patients who underwent radical gastrectomy for distal gastric cancer at our institution between April 2017 and April 2020 were included in this study,with a follow-up period of 12-26 mo.The patients were assigned to four groups based on the stapler and DTR plan as follows:BillrothⅠ(B-I)reconstruction+linear stapler group(group A,22 cases),B-I reconstruction+circular stapler group(group B,22 cases),Billroth II(B-II)reconstruction+linear stapler group(group C,22 cases),and B-II reconstruction+circular stapler group(group D,21 cases).The pathological parameters,postoperative gastrointestinal function recovery,postoperative complications,and quality of life(QOL)were compared among the four groups.RESULTS No significant differences in the maximum diameter of the gastric tumors,total number of lymph nodes dissected,drainage tube removal time,QLQ(QOL questionnaire)-C30 and QLQ-STO22 scores at 1 year postoperatively,and incidence of complications were observed among the four groups(P>0.05).However,groups A and C(linear stapler)had significantly lower intraoperative blood loss and significantly shorter anastomosis time,operation time,first fluid diet intake time,first exhaust time,and length of postoperative hospital stay(P<0.05)than groups B and D(circular stapler).CONCLUSION Linear staplers offer several advantages for postoperative recovery.B-I and B-II reconstruction methods had similar effects on QOL.The optimal solution can be selected according to individual conditions and postoperative convenience.

Transcriptomic analysis reveals the defense mechanisms of citrus infested with Diaphorina citri

Huanglongbing(HLB) is a devastating disease that has led to an acute crisis for growers of citrus, one of the world's most important fruit crops. The phloem-feeding Asian citrus psyllid(ACP), Diaphorina citri, is the main pest at the new shoot stage and is the only natural vector of HLB pathogenic bacteria. Little is known about how plants perceive and defend themselves from this destructive pest. Here, we characterized changes in the expression of various genes in citrus plants that were continuously infested by D. citri for different durations(12, 24, and 48 h). A total of 5 219 differentially expressed genes(DEGs) and 643 common DEGs were identified across all time points. Several pathways related to defense were activated, such as peroxisome, alpha-linolenic acid metabolism, and phenylpropanoid and terpenoid biosynthesis, and some pathways related to growth and signal transduction were suppressed in response to D. citri infestation. The expression of genes including kinases(CML44, CIPK6, and XTH6), phytohormones(SAMT, LOX6, and NPR3), transcription factors(bHLH162, WRKY70, and WRKY40), and secondary metabolite synthesis-related genes(PAL, 4CL2, UGT74B1 and CYP82G1) was significantly altered in response to D. citri infestation. The findings of this study greatly enhance our understanding of the mechanisms underlying the defense response of citrus plants to D. citri infestation at the molecular level. Functional characterization of the candidate defense-related genes identified in this study will aid the molecular breeding of insect-resistant citrus varieties.

Generating barcodes for nanopore sequencing data with PRO

DNA barcodes,short and unique DNA sequences,play a crucial role in sample identification when processing many samples simultaneously,which helps reduce experimental costs.Nevertheless,the low quality of long-read sequencing makes it difficult to identify barcodes accurately,which poses significant challenges for the design of barcodes for large numbers of samples in a single sequencing run.Here,we present a comprehensive study of the generation of barcodes and develop a tool,PRO,that can be used for selecting optimal barcode sets and demultiplexing.We formulate the barcode design problem as a combinatorial problem and prove that finding the optimal largest barcode set in a given DNA sequence space in which all sequences have the same length is theoretically NP-complete.For practical applications,we developed the novel method PRO by introducing the probability divergence between two DNA sequences to expand the capacity of barcode kits while ensuring demultiplexing accuracy.Specifically,the maximum size of the barcode kits designed by PRO is 2,292,which keeps the length of barcodes the same as that of the official ones used by Oxford Nanopore Technologies(ONT).We validated the performance of PRO on a simulated nanopore dataset with high error rates.The demultiplexing accuracy of PRO reached 98.29%for a barcode kit of size 2,922,4.31%higher than that of Guppy,the official demultiplexing tool.When the size of the barcode kit generated by PRO is the same as the official size provided by ONT,both tools show superior and comparable demultiplexing accuracy.

A simple hydroxypyridine ionic liquids for conversion of CO_(2)into quinazoline-2,4(1H,3H)-diones under atmospheric conditions

The transformation of CO_(2)into high value-added product is a promising pathway for utilizing CO_(2).However,the process tends to require harsh reaction conditions owing to CO_(2)chemical inertness.Designing a high efficiency catalytic system with environmentally benign characteristic are important determinants.In this work,protic ionic liquids[TMG][2-OPy]were prepared via one-step neutralization between 1,1,3,3-tetramethylguanidine and 2-hydroxypyridine,applying to the domain of synthesizing quinzoline-2,4(1 H,3H)-diones from CO_(2)and 2-aminobenzontiles without any solvent or metal,achieving the yield of 97%at 90℃for 8 h under atmospheric.A series of substrates with good to acceptable yield were detected,revealing the generality and universality of the catalyst.Furthermore,the system could be facilely reused for at least six runs,retaining the yield of 94%.A preliminary kinetic equation is calculated with the activation energy of 68 kJ·mol^(-1),and a plausible reaction mechanism was put forward.This study highlights that the[TMG][2-OPy]enables to activate CO_(2)carboxylation efficiently.

Identification of lncRNAs associated with T cells as potentialbiomarkers and therapeutic targets in lung adenocarcinoma

Lung adenocarcinoma (LUAD) is the most common and deadliest subtype of lung cancer. To select moretargeted and effective treatments for individuals, further advances in classifying LUAD are urgently needed. Thenumber, type, and function of T cells in the tumor microenvironment (TME) determine the progression andtreatment response of LUAD. Long noncoding RNAs (lncRNAs), may regulate T cell differentiation, development,and activation. Thus, our aim was to identify T cell-related lncRNAs (T cell-Lncs) in LUAD and to investigatewhether T cell-Lncs could serve as potential stratifiers and therapeutic targets. Seven T cell-Lncs were identified tofurther establish the T cell-related lncRNA risk score (TRS) in LUAD. Low TRS individuals were characterized byrobust immune status, fewer genomic alterations, and remarkably longer survival than high TRS individuals. Theexcellent accuracy of TRS in predicting overall survival (OS) was validated in the TCGA-LUAD training cohort andthe GEO-LUAD validation cohort. Our data demonstrated the favorable predictive power of the TRS-basednomogram, which had important clinical significance in estimating the survival probability for individuals. Inaddition, individuals with low TRS could respond better to chemotherapy and immunotherapy than those with highTRS. LINC00525 was identified as a valuable study target, and the ability of LUAD to proliferate or invade wassignificantly attenuated by downregulation of LINC00525. In conclusion, the TRS established by T cell-Lncs couldunambiguously classify LUAD patients, predict their prognosis and guide their management. Moreover, our identifiedT cell-Lncs could provide potential therapeutic targets for LUAD.

Detection of Citrus Psyllid Based on Improved YOLOX Model

[Objectives]The paper was to explore a faster and more accurate detection method for citrus psyllid to prevent and control yellow-shoot disease and inhibit its transmission.[Methods]We used an improved YOLOX based edge detection method for psyllid,added Convolutional Block Attention Module(CBAM)to the backbone network,and further extracted important features in the channel and space dimensions.The Cross Entropy Loss in the object loss was changed to Focal Loss to further reduce the missed detection rate.[Results]The algorithm described in the study fitted in with the detection platform of psyllid.The data set of psyllid was taken in Lianjiang Orange Garden,Zhanjiang City,Guangdong Province,deeply adapted to the actual needs of agricultural and rural development.Based on YOLOX model,the backbone network and loss function were improved to achieve a more excellent detection method of citrus psyllid.The AP value of 85.66%was obtained on the data set of citrus psyllid,which was 2.70%higher than that of the original model,and the detection accuracies were 8.61%,4.32%and 3.62%higher than that of YOLOv3,YOLOv4-Tiny and YOLOv5-s,respectively,which had been greatly improved.[Conclusions]The improved YOLOX model can better identify citrus psyllid,and the accuracy rate has been improved,laying a foundation for the subsequent real-time detection platform.

乳杆菌抑制幽门螺杆菌感染的分子机制

乳杆菌具有调节胃肠道菌群、改善胃肠道功能的益生作用。幽门螺杆菌是定植于胃黏膜的革兰阴性致病菌,可诱发胃癌。目前,幽门螺杆菌根除率逐年下降,临床上开始尝试应用嗜酸乳杆菌、鼠李糖乳杆菌和加氏乳杆菌等乳杆菌联合抗生素治疗幽门螺杆菌。然而不同临床研究结论有差异,临床疗效仍有待提升。该文通过综述乳杆菌治疗幽门螺杆菌的临床研究,进一步探讨其抑制幽门螺杆菌感染的分子机制,包括细菌素的直接杀菌、黏附抑制、胃肠道微生物群调节、炎症抑制等,为筛选理想乳杆菌菌株,提高幽门螺杆菌临床疗效提供新方案。

白内障超声乳化手术前后眼表的变化

目的:应用眼表综合分析仪联合结膜印记细胞学观察白内障超声乳化手术前后眼表参数的变化。方法:选择2016-12/2017-12于福建省立医院眼科行白内障超声乳化和人工晶状体植入手术的患者39例39眼。观察和分析患者术前,术后1d,1wk,1、2mo的干眼症状评估OSDI量表。应用眼表综合分析仪(Keratograph5M)测量泪河高度、泪膜破裂时间、结膜充血以及进行结膜印迹细胞学检查。结果:术前,术后1d,1wk,1、2mo的OSDI量表的评分:9.30±3.80、19.8±3.42、33.2±5.63、18.8±3.49、20.3±8.65分(P<0.05);结膜杯状细胞密度分别是376.00±73.88、289±69.50、243.02±80.81、336.72±81.60、346.70±67.35个/mm 2(P<0.05);首次泪膜破裂时间分别是6.91±4.52、6.12±3.55、5.18±3.37、6.28±4.70、5.96±3.17s,平均泪膜破裂时间分别是10.21±5.20、8.89±4.47、6.87±3.68、7.35±3.52、9.00±4.23s,术后1wk的泪膜破裂时间与术前有差异(P<0.05)。结论:白内障超声乳化手术破坏眼表,患者的泪膜稳定性和结膜细胞损害于术后1d开始,术后1wk加剧,术后2mo患者的眼表状态仍然无法完全恢复。

电针对透镜诱导型近视豚鼠脉络膜血流和内皮素-1及其受体表达的影响

目的:观察透镜诱导型近视豚鼠脉络膜毛细血管密度的变化,探讨脉络膜内皮素-1(ET-1)、内皮素受体A(ETAR)及受体B(ETBR)的表达变化及电针治疗机制。方法:将54只豚鼠随机分为正常对照组(NC组)、透镜诱导组(LIM组)和电针+透镜诱导组(LIM+EA组)。NC组正常饲养,不干预;LIM组和LIM+EA组右眼配戴-6.00D透镜片,建立近视模型。造模2、4wk测量各组豚鼠屈光度、眼轴和脉络膜毛细血管密度,实时荧光定量PCR(q-PCR)、酶联免疫吸附试验(ELISA)和免疫组化检测各组脉络膜ET-1、ETAR和ETBR mRNA及蛋白表达水平。结果:造模2、4wk后,与NC组相比,LIM组和LIM+EA组近视屈光度和眼轴均增加(均P<0.001);LIM+EA组与LIM组相比,屈光度和眼轴均减小(均P<0.05)。造模2、4wk后,与NC组相比,LIM组脉络膜毛细血管密度均降低(P<0.001),脉络膜ET-1、ETAR及ETBR mRNA和蛋白水平均增加(均P<0.05);而LIM+EA组与LIM组相比,脉络膜毛细血管密度升高(P<0.01),脉络膜ET-1、ETAR及ETBR mRNA和蛋白水平均降低。结论:在透镜诱导型近视豚鼠中,随着屈光度和眼轴的增长脉络膜血流减少,而电针可能通过神经调控改善了脉络膜的血流,影响了血管剪切力,下调ET-1及其受体含量以延缓近视的发生发展。

A Regional Ocean Reanalysis System for Coastal Waters of China and Adjacent Seas

A regional ocean reanalysis system for the coastal waters of China and adjacent seas has been developed by the National Marine Data and Information Service（NMDIS）.It produces a dataset package called CORA （China ocean reanalysis）.The regional ocean model used is based on the Princeton Ocean Model with a generalized coordinate system（POMgcs）.The model is parallelized by NMDIS with the addition of the wave breaking and tidal mixing processes into model parameterizations.Data assimilation is a sequential three-dimensional variational（3D-Var） scheme implemented within a multigrid framework.Observations include satellite remote sensing sea surface temperature（SST）,altimetry sea level anomaly（SLA）,and temperature/salinity profiles.The reanalysis fields of sea surface height,temperature,salinity,and currents begin with January 1986 and are currently updated every year. Error statistics and error distributions of temperature,salinity and currents are presented as a primary evaluation of the reanalysis fields using sea level data from tidal gauges,temperature profiles,as well as the trajectories of Argo floats.Some case studies offer the opportunity to verify the evolution of certain local circulations.These evaluations show that the reanalysis data produced provide a good representation of the ocean processes and phenomena in the coastal waters of China and adjacent seas.

Comparison of different methods of intestinal obstruction in a rat model

AIM:To investigate different methods of creating incomplete intestinal obstruction in a rat model and to compare their electrophysiologic,morphologic and histologic characteristics. METHODS:Rat ileum was partially obstructed by the respective application of:braided silk(penetrated the mesentery and surrounded intestine);half ligation (penetrated directly and ligated 1/2 cross-section of the intestine);wide pipe(6 mm in width,surrounded the intestine);narrow pipe(2 mm in width,surrounded the intestine).A control was also included(no obstruction). Various behavioral and electrophysiologic variables, as well as morphologic and immunohistochemical observations were recorded by blinded investigators at different time points(12,24,48,72 h),including daily general condition,ileal wet weight and circumference, macromorphous and micromorphous intestine,bowel movement capability in vivo and in vitro,slow wave and neural electrical activity,and the number of c-Kit positive interstitial cells of Cajal(ICC). RESULTS:Despite being of a similar general condition, these methods resulted in different levels of obstruction in each group compared with the control at different time points(12,24,48,72 h).However,these fields of the wide pipe rat showed significantly differences when compared with the other three obstructed groups at 12 to 72 h,including macroscopic and histological presentation,intestinal transit ratio and contractility,circumference and wet weight,amplitude and frequency of nerve electrical discharge and slow wave,and ICC numbers(all P<0.01). CONCLUSION:The wide pipe rat method is significantly more reliable and stable than the other methods of obstruction,demonstrating that use of the wide pipe method can be a useful model of incomplete intestinal obstruction.

EF-Hand蛋白研究进展

EF-hand蛋白作为钙离子结合蛋白家族中的特殊成员和钙离子一起参与了从细胞增殖到细胞凋亡各方面的功能调节,EF-hand蛋白调节信号的异常也被认为是人类多种疾病的诱因。按照功能分类,EF-hand蛋白可以分为具有调控功能的Ca2+信号蛋白和只参与Ca2+转运、缓冲的Ca2+缓冲蛋白两大类。EF-hand蛋白功能的多样性与EF-hand结构的构象、组织形式、对钙离子的响应程度等密切相关。本文就EF-hand蛋白结构与功能的差异以及与疾病的关系进行简要综述。

Orbital period changes of the W UMa binary YY Eri

Orbital period changes of the W UMa-type binary YY Eri are analyzed by using all photoelectric and ccd times of light minimum. The results show that its orbital period is undergo- ing a secular increase superposed on two cyclic oscillations. The continuous increase at the rate of dP/dt = 6.3806 × 10^-8 d yr^-1 may be accounted for by mass transfer from the less massive com- panion to the more massive one. Two periodic variations with periods of 38.6192 and 22.3573 yr may be attributed to the light-time effect of a faint third star and the cyclic magnetic activity of the system, respectively.