Hypergraph Computation

Practical real-world scenarios such as the Internet,social networks,and biological networks present the challenges of data scarcity and complex correlations,which limit the applications of artificial intelligence.The graph structure is a typical tool used to formulate such correlations,it is incapable of modeling highorder correlations among different objects in systems;thus,the graph structure cannot fully convey the intricate correlations among objects.Confronted with the aforementioned two challenges,hypergraph computation models high-order correlations among data,knowledge,and rules through hyperedges and leverages these high-order correlations to enhance the data.Additionally,hypergraph computation achieves collaborative computation using data and high-order correlations,thereby offering greater modeling flexibility.In particular,we introduce three types of hypergraph computation methods:①hypergraph structure modeling,②hypergraph semantic computing,and③efficient hypergraph computing.We then specify how to adopt hypergraph computation in practice by focusing on specific tasks such as three-dimensional(3D)object recognition,revealing that hypergraph computation can reduce the data requirement by 80%while achieving comparable performance or improve the performance by 52%given the same data,compared with a traditional data-based method.A comprehensive overview of the applications of hypergraph computation in diverse domains,such as intelligent medicine and computer vision,is also provided.Finally,we introduce an open-source deep learning library,DeepHypergraph(DHG),which can serve as a tool for the practical usage of hypergraph computation.

北京2022年冬奥会六足冰壶机器人机构设计与运动规划

When a curling rock slides on an ice sheet with an initial rotation,a lateral movement occurs,which is known as the curling phenomenon.The force of friction between the curling rock and the ice sheet changes continually with changes in the environment;thus,the sport of curling requires great skill and experience.The throwing of the curling rock is a great challenge in robot design and control,and existing curling robots usually adopt a combination scheme of a wheel chassis and gripper that differs significantly from human throwing movements.A hexapod curling robot that imitates human kicking,sliding,pushing,and curling rock rotating was designed and manufactured by our group,and completed a perfect show during the Beijing 2022 Winter Olympics Games.Smooth switching between the walking and throwing tasks is realized by the robot’s morphology transformation based on leg configuration switching.The robot’s controlling parameters,which include the kicking velocity v_(k),pushing velocity v_(p),orientation angle θc,and rotation velocityω,are determined by aiming and sliding models according to the estimated equivalent friction coefficientμ_(equ)and ratio e of the front and back frictions.The stable errors between the target and actual stopping points converge to 0.2 and 1.105 m in the simulations and experiments,respectively,and the error shown in the experiments is close to that of a well-trained wheelchair curling athlete.This robot holds promise for helping ice-makers rectify ice sheet friction or assisting in athlete training.

New advances of adiponectin in regulating obesity and related metabolic syndromes

Obesity and related metabolic syndromes have been recognized as important disease risks,in which the role of adipokines cannot be ignored.Adiponectin(ADP)is one of the key adipokines with various beneficial effects,including improving glucose and lipid metabolism,enhancing insulin sensitivity,reducing oxidative stress and inflammation,promoting ceramides degradation,and stimulating adipose tissue vascularity.Based on those,it can serve as a positive regulator in many metabolic syndromes,such as type 2 diabetes(T2D),cardiovascular diseases,non-alcoholic fatty liver disease(NAFLD),sarcopenia,neurodegenerative diseases,and certain cancers.Therefore,a promising therapeutic approach for treating various metabolic diseases may involve elevating ADP levels or activating ADP receptors.The modulation of ADP genes,multimerization,and secretion covers the main processes of ADP generation,providing a comprehensive orientation for the development of more appropriate therapeutic strategies.In order to have a deeper understanding of ADP,this paper will provide an all-encompassing review of ADP.

Lesch-Nyhan综合征家兔模型的建立及其表型分析

Lesch-Nyhan综合征(Lesch-Nyhan syndrome,LNS)是一种先天性的嘌呤代谢缺陷病,次黄嘌呤鸟嘌呤磷酸核糖转移酶(hypoxanthine phosphoribosyltransferase,HPRT)是其主要致病基因,临床特征表现为尿酸分泌过多、痛风、肾结石及肾脏损伤等,目前致病机制尚未被完全阐明且无有效治愈手段。动物模型在疾病致病机理研究和治疗方式探索中发挥着重要功能。本研究采用高效的CRISPR/Cas9基因编辑技术和显微注射的方式敲除家兔(Oryctolagus cuniculus)HPRT基因建立了LNS家兔模型,以期能更好的模拟该疾病的表型。首先针对兔HPRT基因第3外显子设计一条sgRNA,将体外转录的sgRNA和Cas9 mRNA共注射到兔受精卵中,注射后的胚胎移植到代孕母兔子宫中,待仔兔出生后对其基因型及表型进行鉴定与分析。共出生4只仔兔(分别编号为R1、R2、R3和R4),测序结果显示4只仔兔都产生了不同程度的基因修饰,基因编辑效率达100%,其中R4仔兔T载体测序结果在基因编辑靶点未检测到野生型序列。通过6-硫代鸟嘌呤(6-Thioguanine,6-TG)药物测试,证明R4仔兔HPRT酶活性缺失;肾组织HE染色发现4只仔兔表现出肾小球炎细胞浸润、集合管脱落等肾脏损失。本研究成功设计了1条能够敲除家兔HPRT基因的sgRNA,并采用CRISPR/Cas9基因编辑技术和显微注射方式成功构建了HPRT基因修饰家兔,为研究LNS综合征致病机制和治疗方式提供了新的非啮齿类动物模型。

Crocus sativus L.produces anti-inflammatory effects and regulates the NLRP3–NF-κB pathway

Objective:This study aimed to evaluate the anti-inflammatory effects of petal and stamen extracts of saffron crocus(Crocus sativus)and explore the underlying mechanism.Methods:Local and systemic inflammation models were used to investigate the anti-inflammatory effects of C.sativus.A xyleneinduced inflammation model or lipopolysaccharide(LPS)-induced inflammation model was used in this study.C.sativus petal and stamen extracts were each administered to the mice in the xylene and LPS models by gavage for 14 d at 0.1 and 0.4 g/kg doses,respectively.Enzyme-linked immunosorbent assay(ELISA)was used to measure the concentrations of tumor necrosis factor(TNF)-αand interleukin(IL)-1βin mouse serum.Hematoxylin and eosin(H&E)staining was used to observe the pathological changes in the ear in the xylene-induced inflammation model and in the spleen in the LPS-induced inflammation model.NOD-like receptor thermal protein domain associated protein 3(NLRP3)protein levels within the nuclear factor-kappa B(NF-κB)pathway were assessed using western blotting.RAW264.7 cells were treated with LPS(5μg/mL)and LPS+C.sativus(0.05,0.1,and 0.2 mg/mL)for 24 h,and a Cell Counting Kit-8 was used to measure cell proliferation.Changes in NLRP3 and NF-κB levels were evaluated by western blotting.Results:Petal and stamen extracts of C.sativus attenuated the anti-inflammatory effects in local or systemic inflammatory models and repaired pathological changes in the ear in the xylene-induced inflammation model and spleen in the LPS-induced inflammation model.These extracts also decreased the concentrations of TNF-αand IL-1βin the mouse serum in the LPS-induced inflammation model.C.sativus downregulated NLRP3 protein level through the NF-κB pathway and downregulated LC-3 and BECLIN1 in vivo and in vitro.Carbonyl Cyanide3-ChloroPhenylhydrazone(CCCP)weakened the effects of C.sativus on the NLRP3–NF-κB pathway.Conclusion:C.sativus has anti-inflammatory effects and regulates the NLRP3-NF-κB pathway.

Ferulic acid reduces inflammatory response induced by radiation through Sirt1-NLRP3 pathway

Objective:A model of inflammatory damage was induced by radiation to investigate whether ferulic acid(FA)can reduce the inflammatory response through the Sirt1-NLRP3 inflammatory pathway.This will help discover radiation-protective drugs and elucidate the molecular mechanisms related to radiation-induced inflammatory damage.Methods:A mouse model of radiation-induced immunoinflammatory injury was established to verify the anti-inflammatory effects of FA in vivo.C57BL/6J mice were randomly divided into six groups,and 5 Gy whole-body irradiation was used for modeling.Mice were administered a gastric solvent,amifostine,or 25,50,or 100 mg/kg FA daily for 12 days,consecutively,before irradiation.The serum of mice was collected 24 hour after irradiation to observe the content of inflammatory factors interleukin(IL)-1β,IL-18,IL-6,and tumor necrosis factor(TNF)-α.The spleen and thymus tissues of mice were weighed and the organ index was calculated for pathological testing and immunofluorescence detection.Results:FA reduced the radiation-induced decrease in the spleen and thymus indices.FA significantly reduced the secretion of inflammatory factors in the serum and reversed the radiation-induced reduction in lymphocytes in the spleen and thymus of mice.FA activated Sirt1 and inhibited the expression of the NLRP3 inflammasome to alleviate the inflammatory response.Conclusions:FA reduced radiation-induced inflammation in animals,possibly by activating Sirt1 and reducing nucleotide oligomerization domain(NOD)-like receptor thermal protein domain associated protein 3(NLRP3)inflammasome expression,thereby reducing the secretion of inflammatory factors.

Effectiveness of onsite and online education in enhancing knowledge and use of human immunodeficiency virus pre-and postexposure prophylaxis

BACKGROUND Enhancing awareness and use of pre-exposure prophylaxis(PrEP)and postexposure prophylaxis(PEP)is vital to curb human immunodeficiency virus(HIV)spread.High-risk behaviors prevalent among sexually transmitted infection clinic outpatients underscore the need for increased PrEP/PEP education in this group.AIM To investigate the effects of both onsite and online health education on the knowledge of,and willingness to use,PrEP and PEP among individuals receiving PEP services.METHODS Participants were drawn from a cohort study on PEP service intervention at an STD/AIDS outpatient clinic in designated HIV/AIDS hospitals in Beijing,conducted from January 1 to June 30,2022.Health education was provided both onsite and online during follow-up.Surveys assessing knowledge of,and willingness to use,PrEP/PEP were administered at baseline and again at 24 wk post-intervention.RESULTS A total of 112 participants were enrolled in the study;105 completed the follow-up at week 24.The percentage of participants with adequate knowledge of,and willingness to use,PrEP significantly increased from 65.2%and 69.6%at baseline to 83.8%and 82.9%at the end of the intervention(both P<0.05).Similarly,those with adequate knowledge of,and willingness to use,PEP increased from 74.1%and 77.7%at baseline to 92.4%and 89.5%at week 24(P<0.05).Being between 31 years and 40 years of age,having a postgraduate degree or higher,and reporting a monthly expenditure of RMB 5000 or more were found to be significantly associated with knowledge of PrEP and PEP(both P<0.05).CONCLUSION The findings show that both onsite and online health education significantly improved the knowledge of,and increased willingness to use,PrEP and PEP in individuals utilizing PEP services.

Predictive value of angiopoietin-like protein 8 in metabolic dysfunction-associated fatty liver disease and its progression:A case-control study

BACKGROUND The prevalence of metabolic dysfunction-associated fatty liver disease(MAFLD)is rapidly increasing,currently affecting approximately 25%of the global population.Liver fibrosis represents a crucial stage in the development of MAFLD,with advanced liver fibrosis elevating the risks of cirrhosis and hepatocellular carcinoma.Simple serum markers are less effective in diagnosing liver fibrosis compared to more complex markers.However,imaging techniques like transient elastography face limitations in clinical application due to equipment and technical constraints.Consequently,it is imperative to identify a straightforward yet effective method for assessing MAFLD-associated liver fibrosis.AIM To investigate the predictive value of angiopoietin-like protein 8(ANGPTL8)in MAFLD and its progression.METHODS We analyzed 160 patients who underwent abdominal ultrasonography in the Endocrinology Department,Xiaogan Central Hospital affiliated to Wuhan University of Science and Technology,during September 2021-July 2022.Using abdominal ultrasonography and MAFLD diagnostic criteria,among the 160 patients,80 patients(50%)were diagnosed with MAFLD.The MAFLD group was divided into the liver fibrosis group(n=23)and non-liver fibrosis group(n=57)by using a cut-off fibrosis-4 index≥1.45.Logistical regression was used to analyze the risk of MAFLD and the risk factors for its progression.Receiver operating characteristic curves were used to evaluate the predictive value of serum ANGPTL8 in MAFLD and its progression.RESULTS Compared with non-MAFLD patients,MAFLD patients had higher serum ANGPTL8 and triglyceride-glucose(TyG)index(both P<0.05).Serum ANGPTL8(r=0.576,P<0.001)and TyG index(r=0.473,P<0.001)were positively correlated with MAFLD.Serum ANGPTL8 was a risk factor for MAFLD[odds ratio(OR):1.123,95%confidence interval(CI):1.066-1.184,P<0.001).Serum ANGPTL8 and ANGPTL8+TyG index predicted MAFLD[area under the curve(AUC):0.832 and 0.886,respectively;both P<0.05].Compared with MAFLD patients without fibrosis,those with fibrosis had higher serum ANGPTL8 and TyG index(both P<0.05),and both parameters were positively correlated with MAFLD-associated fibrosis.Elevated serum ANGPTL8(OR:1.093,95%CI:1.044-1.144,P<0.001)and TyG index(OR:2.383,95%CI:1.199-4.736,P<0.013)were risk factors for MAFLD-associated fibrosis.Serum ANGPTL8 and ANGPTL8+TyG index predicted MAFLD-associated fibrosis(AUC:0.812 and 0.835,respectively;both P<0.05).CONCLUSION The serum levels of ANGPTL8 are elevated and positively correlated with MAFLD.They can serve as predictors for the risk of MAFLD and liver fibrosis,with the ANGPTL8+TyG index potentially exhibiting even higher predictive value.

基于PLC的智能手环全自动充电触点铜柱装配机设计

智能手环的市场需求量持续增大,但因其结构复杂精细,传统人工装配生产效率低下且易因疲劳导致装配精度较差等质量问题。对此,提出一款基于PLC集成的智能手环充电触点铜柱全自动安装设备。设备采用可编程控制器PLC作为核心控制器,通过光电传感器和磁性开关采集机械装置工作状态信息并进行实时反馈与控制,实现智能手环充电触点铜柱全自动安装,推动智能手环产能、装配质量与优品率协同提升。

The Antidepressant Mechanism of JiaWeiWenDan Decoction Regulating p38MAPK-ERK5 Signal Transduction Pathway

Objective: To investigate the anti-depression mechanism of JiaWeiWenDan Decoction in regulating p38MAPK-ERK5 signal transduction pathway. Methods: Depression model rats were randomly divided into Blank Control Group, Model Control Group, Chinese Medicine Treatment Group, and Western Medicine Treatment Group (hereinafter referred to as Blank Group, Model Group, Chinese Medicine Group, and Western Medicine Group), with 48 rats in each group. The mice were treated with p38MAPK-ERK5 on the 7th day, 14th day and 21st day, respectively, and the mice were treated for 28 days. The key targets and cytokines in p38MAPK-ERK5 signal transduction pathway were detected. Results: Compared with the Blank Group, the expression of p38MAPKmRNA in the hippocampus of the Model Group was increased. The Chinese Medicine Group and Western Medicine Group could reduce the expression of p38MAPK mRNA (P P P P Conclusion: The anti-inflammatory effect of JiaWeiWenDan Decoction may be related to the regulation of p38MAPK-ERK5 signaling pathway. With the advance of the treatment week, the best effect was obtained when the treatment was started on the 7th day of modeling.

摩罗丹致药物性肝损伤1例

患者,女,60岁,因慢性萎缩性胃炎予摩罗丹(16丸,po,tid)、奥美拉唑(20 mg,po,bid)等药物治疗后出现乏力、纳差、厌油腻、皮肤巩膜黄染、尿黄等症状,肝功能指标显著升高,丙氨酸氨基转移酶(ALT)1483 U·L^(-1),天冬氨酸氨基转移酶(AST)1066 U·L^(-1),碱性磷酸酶(AKP)351 U·L^(-1),γ-谷氨酰转肽酶(γ-GT)246 U·L^(-1),总胆红素(TBil)28.4μmol·L^(-1),直接胆红素(DBil)24.9μmol·L^(-1)。患者用药前肝功能正常,既往有摩罗丹导致肝功能损伤的病史,根据药物性肝损伤的Roussel Uclaf因果关系评估法,得分9分,考虑“极可能”是摩罗丹导致的药物性肝损伤,予停用摩罗丹并给予保肝治疗,肝功能恢复正常,随访半年,肝功能指标未见异常。

A Scd1-mediated metabolic alteration participates in liver responses to low-dose bavachin

Hepatotoxicity induced by bioactive constituents in traditional Chinese medicines or herbs,such as bavachin(BV)in Fructus Psoraleae,has a prolonged latency to overt drug-induced liver injury in the clinic.Several studies have described BV-induced liver damage and underlying toxicity mechanisms,but little attention has been paid to the deciphering of organisms or cellular responses to BV at no-observed-adverse-effect level,and the underlying molecular mechanisms and specific indicators are also lacking during the asymptomatic phase,making it much harder for early recognition of hepatotoxicity.Here,we treated mice with BV for 7 days and did not detect any abnormalities in biochemical tests,but found subtle steatosis in BV-treated hepatocytes.We then profiled the gene expression of hepatocytes and non-parenchymal cells at single-cell resolution and discovered three types of hepatocyte subsets in the BV-treated liver.Among these,the hepa3 subtype suffered from a vast alteration in lipid metabolism,which was characterized by enhanced expression of apolipoproteins,carboxylesterases,and stearoyl-CoA desaturase 1(Scd1).In particular,increased Scd1 promoted monounsaturated fatty acids(MUFAs)synthesis and was considered to be related to BV-induced steatosis and polyunsaturated fatty acids(PUFAs)generation,which participates in the initiation of ferroptosis.Additionally,we demonstrated that multiple intrinsic transcription factors,including Srebf1 and Hnf4a,and extrinsic signals from niche cells may regulate the above-mentioned molecular events in BV-treated hepatocytes.Collectively,our study deciphered the features of hepatocytes in response to BV insult,decoded the underlying molecular mechanisms,and suggested that Scd1 could be a hub molecule for the prediction of hepatotoxicity at an early stage.

Nanomedicine-boosting icaritin-based immunotherapy of advanced hepatocellular carcinoma

Traditional treatments for advanced hepatocellular carcinoma(HCC),such as surgical resection,transplantation,radiofrequency ablation,and chemotherapy are unsatisfactory,and therefore the exploration of powerful therapeutic strategies is urgently needed.Immunotherapy has emerged as a promising strategy for advanced HCC treatment due to its minimal side effects and long-lasting therapeutic memory effects.Recent studies have demonstrated that icaritin could serve as an immunomodulator for effective immunotherapy of advanced HCC.Encouragingly,in 2022,icaritin soft capsules were approved by the National Medical Products Administration(NMPA)of China for the immunotherapy of advanced HCC.However,the therapeutic efficacy of icaritin in clinical practice is impaired by its poor bioavailability and unfavorable in vivo delivery efficiency.Recently,functionalized drug delivery systems including stimuli-responsive nanocarriers,cell membrane-coated nanocarriers,and living cell-nanocarrier systems have been designed to overcome the shortcomings of drugs,including the low bioavailability and limited delivery efficiency as well as side effects.Taken together,the development of icaritin-based nanomedicines is expected to further improve the immunotherapy of advanced HCC.Herein,we compared the different preparation methods for icaritin,interpreted the HCC immune microenvironment and the mechanisms underlying icaritin for treatment of advanced HCC,and discussed both the design of icaritin-based nanomedicines with high icaritin loading and the latest progress in icaritinbased nanomedicines for advanced HCC immunotherapy.Finally,the prospects to promote further clinical translation of icaritin-based nanomedicines for the immunotherapy of advanced HCC were proposed.

老年患者术中每搏变异度指导液体治疗对肾功能的影响

目的:探讨老年患者在硬膜外联合全身麻醉下实施腹腔镜结直肠癌根治术,术中使用每搏变异度(stroke volume variation,SVV)指导液体治疗对肾功能的影响。方法:前瞻性选取内蒙古医科大学附属医院100例老年患者在硬膜外联合全身麻醉下行腹腔镜结直肠癌根治术,随机分为对照组(C组)和试验组(S组),每组50例。C组采用常规补液法,S组在SVV指导下行液体补液。评估比较两组患者术前、术后血清肌酐(serum creatinine,Scr)、血尿素氮(blood urea nitrogen,BUN)、中性粒细胞明胶酶相关脂钙蛋白(neutrophil gelatinase-associated lipocalin protein,NGAL)、肾损伤分子-1(kidney injury molecule-1,KIM-1)。结果:S组术后2 h、24 h的NGAL浓度均较C组降低(P=0.033,P=0.014)。S组术后24 h的KIM-1明显低于C组(P=0.012)。S组术后1天Scr明显低于C组(P=0.049)。C组术后急性肾损伤(acute kidney injury,AKI)发生率显著高于S组(P=0.027)。结论:老年患者腹腔镜结直肠癌根治术中,使用SVV指导液体治疗,可降低术后血清中肾损伤标记物浓度及术后AKI的发生率,对肾功能有保护作用。

Inosine:A broad-spectrum anti-inflammatory against SARS-CoV-2 infection-induced acute lung injury via suppressing TBK1 phosphorylation

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced cytokine storms constitute the primary cause of coronavirus disease 19(COVID-19)progression,severity,criticality,and death.Glucocorticoid and anti-cytokine therapies are frequently administered to treat COVID-19,but have limited clinical efficacy in severe and critical cases.Nevertheless,the weaknesses of these treatment modalities have prompted the development of anti-inflammatory therapy against this infection.We found that the broad-spectrum anti-inflammatory agent inosine downregulated proinflammatory interleukin(IL)-6,upregulated anti-inflammatory IL-10,and ameliorated acute inflammatory lung injury caused by multiple infectious agents.Inosine significantly improved survival in mice infected with SARS-CoV-2.It indirectly impeded TANK-binding kinase 1(TBK1)phosphorylation by binding stimulator of interferon genes(STING)and glycogen synthase kinase-3β(GSK3β),inhibited the activation and nuclear translocation of the downstream transcription factors interferon regulatory factor(IRF3)and nuclear factor kappa B(NF-κB),and downregulated IL-6 in the sera and lung tissues of mice infected with lipopolysaccharide(LPS),H1N1,or SARS-CoV-2.Thus,inosine administration is feasible for clinical anti-inflammatory therapy against severe and critical COVID-19.Moreover,targeting TBK1 is a promising strategy for inhibiting cytokine storms and mitigating acute inflammatory lung injury induced by SARS-CoV-2 and other infectious agents.

Cross-species recognition of bat coronavirus RsYN04 and cross-reaction of SARS-CoV-2 antibodies against the virus

Following the outbreak of coronavirus disease 2019(COVID-19),several severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-related coronaviruses have been discovered.Previous research has identified a novel lineage of SARS-CoV-2-related CoVs in bats,including RsYN04,which recognizes human angiotensin-converting enzyme 2(ACE2)and thus poses a potential threat to humans.Here,we screened the binding of the RsYN04receptor-binding domain(RBD)to ACE2 orthologs from 52animal species and found that the virus showed a narrower ACE2-binding spectrum than SARS-CoV-2.However,the presence of the T484W mutation in the RsYN04 RBD broadened its range.We also evaluated 44 SARS-CoV-2antibodies targeting seven epitope communities in the SARS-CoV-2 RBD,together with serum obtained from COVID-19 convalescents and vaccinees,to determine their cross-reaction against RsYN04.Results showed that no antibodies,except for the RBD-6 and RBD-7 classes,bound to the RsYN04 RBD,indicating substantial immune differences from SARS-CoV-2.Furthermore,the structure of the RsYN04 RBD in complex with cross-reactive antibody S43 in RBD-7 revealed a potently broad epitope for the development of therapeutics and vaccines.Our findings suggest RsYN04 and other viruses belonging to the same clade have the potential to infect several species,including humans,highlighting the necessity for viral surveillance and development of broad anticoronavirus countermeasures.

离合器减振弹簧断裂原因

某型号离合器从动盘总成在扭转耐久性试验过程中,其减振弹簧发生断裂。采用宏观观察、化学成分分析、硬度测试、金相检验、扫描电镜及能谱分析等方法研究了该弹簧断裂的原因。结果表明:减振弹簧内侧存在原始裂纹和摩擦损伤,使弹簧在低应力作用下发生弯曲疲劳断裂。

基于流程管理的高校科研暂付款催收模式研究

随着科教兴国战略的不断推进和完善,高校科研经费持续增加、科研合作范围不断扩大,高校暂付款占流动资产比重不断攀升,严重影响了科研经费使用效率,如何催收暂付款成为高校财务管理工作中亟待解决的难题。本文以某重点T大学为背景,使用问卷调研法和专家访谈法,分析了现阶段高校科研经费暂付款的现状与成因,基于流程管理理论,优化了高校科研暂付款催收的流程,强化自动化催收节点,实现暂付款自动催收。研究有助于提高研究型大学科研暂付款的催收效率。

Development and Demonstration of Australian First Working Sodium Guide Star Laser

The Australian first working sodium guide star laser system has been designed and developed for various astronomical and space-related applications. A completely diode-pumped pulsed system was developed initially followed by a largely fiber-based continuous wave (CW) system operating at 589 nm achieved through a unique wavelength conversion scheme by combining 1342 and 1050 nm through a sum frequency generation process. For the CW system, single-mode laser beams at both 1342 and 1050 nm are achieved from fiber-based seed oscillators and fiber amplifiers. The output power of ~25 W at 1342 nm is achieved from a single frequency fiber Raman amplifier. Output power up to 70 W at 1050 nm is achieved from a Yb-doped fiber pre-amplifier followed by a Yb-doped fiber power amplifier. For the sum frequency generation process, optimum focusing parameters are evaluated and determined. The CW system has generated more than 20 W output power at 589 nm, a circularly polarised beam with a good beam quality, spectral linewidth ≤ 2 MHz, and the laser output locked on the sodium D2 line at 589.159 nm. The system has been successfully demonstrated at EOS Space Research Centre, Mt Stromlo, Canberra, and become the Australian first working sodium guide star laser system.

高能电子束电磁透镜的研究进展

在电子束加工设备中,聚焦系统和偏转系统是决定电子枪性能的关键因素。介绍了电子束聚焦、偏转技术的原理和特点,归纳整理了电磁透镜结构的优化结果、电子束聚焦规律以及减小束斑像差控制等方面所取得的研究进展。分析了目前电磁透镜控制电子束加工中存在的不足,并对未来电子枪发展趋势做出了展望。