40.5 kV及以下C-GIS真空断路器低温环境下机械操作性能的试验研究

40.5 kV及以下C-GIS真空断路器在低温工况下机械操作异常偶有发生,迫切需要提高低温时的机械操作可靠性。对真空断路器低温环境下机械操作性能的影响因素进行了深入分析,并通过试验的方法对低温下的机械操作性能进行了研究。试验结果表明:(1)润滑脂的粘性阻力是影响真空断路器在低温环境下操作异常的主要因素。(2)真空断路器传动链运动副选用低温润滑脂在正常环境温度以及低至-30℃时均可保证正常机械操作。真空断路器的传动链运动副优化及低温润滑脂选用提高了机械操作的稳定性和可靠性。

外加压力和液浸作用下煤中瓦斯解吸特性实验研究

为了研究外加压力和液浸作用下煤样中瓦斯的解吸规律,使用高压注液含瓦斯煤恒温解吸实验装置,以不同时间的瓦斯累计解吸量和解吸速度为评价指标,考察了不同注入压力、不同注入溶液以及不同煤样变质程度对瓦斯解吸特性的影响。结果表明:注入压力越高,注入溶液中复合表面活性剂FHR-1的浓度越大,煤样在不同时间的累计瓦斯解吸量和解吸速度相对就越小;注入压力的升高以及复合表面活性剂FHR-1浓度的增大对瓦斯前期解吸速度的影响相对较大,而对后期解吸速度的影响则相对较小;煤样的变质程度越大,瓦斯累计解吸量和解吸速度相对就越大,其中无烟煤的累计瓦斯解吸量和解吸速度明显大于气煤和褐煤。研究结果认为外加压力和液浸作用下煤层中的瓦斯解吸量和解吸速度均有所减小,注入表面活性剂溶液比注纯水更能有效防止瓦斯突出问题。

烧伤伤员胃肠道屏障损伤机制与治疗药物的研究进展

烧伤休克伤员的救治是医学救援的重要工作之一。烧伤后胃肠道屏障损伤机制仍不明确,胃肠道血流量、胃酸分泌、再灌注损伤等因素都被证实与其有关。目前烧伤后胃肠道屏障损伤的主要治疗药物包括抗生素、谷氨酰胺、整蛋白型肠内营养剂等,但治疗效果并不理想。为提高烧伤的救治水平,本文对烧伤伤员胃肠道屏障损伤的机制、主要药物及新兴疗法进展作一综述。

基于联邦学习的工业互联网平台研究

基于联邦学习,建立“多边”协同训练三层网络架构的工业互联网联邦学习应用平台,将平台架构自上而下分为应用层、ML核心组件层、安全协议层、基础层四层。此平台功能主要为:提供了一种基于数据隐私保护的分布式安全计算框架;为机器学习、深度学习等常用算法提供高性能的安全计算支持;支持同态加密、秘密共享等多种多方安全计算协议,确保数据和模型的安全。通过联邦学习模型在工业互联网平台上的部署进行研究设计,并在预测性维护、资源优化、制造过程优化、安全和风险管理、联合监控和质量控制等多场景中得到应用,为工业领域提供更安全的数据分析和建模解决方案,推动工业互联网智能化转型。

EMS诱变技术在小麦上的应用

小麦遗传基础日趋狭窄成为小麦遗传改良的瓶颈。甲基磺酸乙酯(EMS)是一种高效稳定的烷化类诱变剂,能诱发产生高密度系列等位基因点突变,可在创造作物新品种、新种质、遗传材料以及解决育种工作中某些特殊问题等方面取得突破。本文从EMS诱变的原理和特点着手,简述了小麦EMS诱变及突变体鉴选方法,绘制了EMS诱变研究备选方案图,为小麦科研工作者提供研究思路和参考依据。同时对EMS诱变技术在抗病基因克隆、品质性状改良、叶片持绿机制研究、农艺性状解析、突变体库构建等方面的研究进展进行了前沿报道,分析了EMS诱变在小麦研究中存在的问题及应对方法,并在此基础上对EMS诱变技术在小麦上的发展前景进行展望。这对于丰富小麦遗传资源、加快育种进程和开展基因功能研究具有重要意义。

基于邻域粗糙集概念的一种滚动轴承特征提取方法

针对滚动轴承早期微弱故障识别率偏低的问题,提出一种基于EEMD、邻域粗糙集和模糊C均值聚类(FCM)算法相结合的滚动轴承特征提取方法.该方法将滚动轴承的原始信号进行EEMD分解得到若干个IMF分量,通过均方差和欧氏距离两个评价指标选取出敏感特征分量,构造原始特征数据集,对处理后的原始特征集属性进行NRS约简,剔除冗余属信息,最后将剩余属性的特征数据集作为模糊C均值聚类的输入,实现滚动轴承故障识别.为了对比本文方法对于滚动轴承的故障识别效果,分别添加了FCM、NRS-FCM和EEMD-FCM三种方法进行故障辨识,利用划分系数(PC)和划分熵(CE)对聚类结果进行评价与对比.通过实验表明:邻域粗糙集对于改进滚动轴承的故障识别效果十分明显,具有良好的应用前景.

体系部队“三医联动保障”模式

基于国家医疗联合体发展战略,借鉴国内外医联体建设经验,根据体系保障部队某特战旅官兵医疗救治需求实际,运用文献研究、部队调研、专家咨询等方法,研究探索构建“军队中心医院、地方综合医院、部队卫生队医疗机构”三位一体、联合救治伤员的“三医联动保障”模式及相关理论。总结某院会同驻地地方医院和体系保障部队某特战旅卫生队进行联合保障任务工作经验,进一步探索“三医联动保障模式”的现实可行性,提高部队急危重症伤员的救治时效性,为我军进一步完善部队官兵医疗保障工作探索新思路、积累新经验。

Experimental Realization of a Magnetically Tunable Cavity in a Gyromagnetic Photonic Crystal

We theoretically and experimentally study the cavity modes in a gyromagnetic photonic crystal (GPC).Because the permeability of gyromagnetic material relies on the dc magnetic field exerted upon it,the band gap of the GPC is supposed to be tunable.Based on this,it is expected that the cavity mode in the GPC is also tunable under the variation of dc magnetic fields.The relation between the frequency of the cavity mode and exerted dc magnetic field is theoretically investigated.Furthermore,we measure the frequency variation of the cavity mode in the GPC and demonstrate the tunable property of GPC cavity.

Automated screening of primary cell-based aptamers for targeting and therapy of pancreatic cancer

Although it has been developed for many years, nucleic acid aptamer screening technology still fails to be widely used, a considerable part of it is due to the variability of tumor cell morphology, which leads to the use of immortalized cell lines in the laboratory to screen nucleic acid aptamers for recognition ability of tumor cells in the diseased body.To address this, primary cells that can be stably passaged were isolated and extracted from spontaneous tumors of genetically engineered pancreatic ductal adenocarcinoma model mice in this study.Next, an automated screening instrument for nucleic acid aptamers developed autonomously by our group was used to perform efficient aptamer screening using a limited number of cells, and the obtained nucleic acid aptamers were affinity verified at the cellular level.Finally, to answer the question of the cell growth environment difference on the recognition ability of nucleic acid aptamers, we verified its targeting ability to tumors in vivo on a nude mice xenograft tumor model, and further used a common antitumor drug doxorubicin combined with nucleic acid aptamers to verify the drug loading ability of this aptamer combined with the targeting therapeutic ability.

A human-specific insertion promotes cell proliferation and migration by enhancing TBC1D8B expression

Human-specific insertions play important roles in human phenotypes and diseases.Here we reported a 446-bp insertion(Insert-446)in intron 11 of the TBC1D8B gene,located on chromosome X,and traced its origin to a portion of intron 6 of the EBF1 gene on chromosome 5.Interestingly,Insert-446 was present in the human Neanderthal and Denisovans genomes,and was fixed in humans after human-chimpanzee divergence.We have demonstrated that Insert-446 acts as an enhancer through binding transcript factors that promotes a higher expression of human TBC1D8B gene as compared with orthologs in macaques.In addition,over-expression TBC1D8B promoted cell proliferation and migration through“a dual finger”catalytic mechanism(Arg538 and Gln573)in the TBC domain in vitro and knockdown of TBC1D8B attenuated tumorigenesis in vivo.Knockout of Insert-446 prevented cell proliferation and migration in cancer and normal cells.Our results reveal that the human-specific Insert-446 promotes cell proliferation and migration by upregulating the expression of TBC1D8B gene.These findings provide a significant insight into the effects of human-specific insertions on evolution.

简统化接触网腕臂及定位装置仿真检验技术研究

简统化接触网是中国标准的接触网零部件装备,本文针对简统化接触网腕臂及定位装置的预配成品的仿真检验技术进行了研究,提出了仿真检验的理论算法,并且依托算法设计了自动化监测装备,实现真实模拟接触网弓网关系的自动化装备技术。通过腕臂预配工厂试挂进行预配数据的检验,为简统化接触网的工程应用提供了装备基础。该成果在盐通高铁进行了应用,通过静态、动态检测及试运行,验证了该技术的可靠性,随着简统化接触网的逐步普及,具有较大的推广应用价值。

Recent advancements in DNA nanotechnology-enabled extracellular vesicles detection and diagnosis:A mini review

Extracellular vesicles(EVs)are cell-derived nanosized vesicles widely recognized for their critical roles in various pathophysiological processes.Molecular analysis of EVs is currently being considered an emerging tool for diseases diagnosis.However,the small size and heterogeneity of EVs has staggered the EVs research for diseases diagnosis.DNA nanotechnology enables self-assembly of versatile DNA nanostructures and has shown enormous potential in assisting EVs biosensing.In this review,we briefly introduce the recent advances in DNA nanotechnology approaches for EVs detection.The approaches were categorized based on the dimension of DNA nanostructures.We provide critical evaluation of these approaches,and summarize the pros and cons of specific methods.Further,we discuss the challenges and future perspectives in this field.

CRISPR-Cas13a mediated nanosystem for attomolar detection of canine parvovirus type 2

Canine parvovirus type 2(CPV-2) infection is the most lethal disease of dogs with higher mortality in puppies worldwide.In today’s world,dogs are an integral part of our communities as well as dogs breeding and rearing has become a lucrative business.Therefore,a fast,accurate,portable,and costeffective CPV-2 detection method with the ability for on-site detection is highly desired.In this study,we for the first time proposed a nanosystem for CPV-2 DNA detection with RNA-guided RNA endonuclease Cas13 a,which upon activation results in collateral RNA degradation.We expressed LwCasl3 a in prokaryotic expression system and purified it through nickel column.Activity of Cas13 a was verified by RNA-bound fluorescent group while using a quenched fluorescent probe as signals.Further Cas13 a was combined with Recombinase polymerase amplification(RPA) and T7 transcription to establish molecular detection system termed specific high-sensitivity enzymatic reporter un-locking(SHERLOCK) for sensitive detection of CPV-2 DNA.This nanosystem can detect 100 amol/L CPV-2 DNA within 30 min.The proposed nanosystem exhibited high specificity when tested for CPV-2 and other dog viruses.This CRISPR-Cas13 a mediated sensitive detection approach can be of formidable advantage during CPV-2 outbreaks because it is time-efficient,less laborious and does not involve the use of sophisticated instruments.

Highly sensitive smartphone-based detection of Listeria monocytogenes using SYTO9

Listeriosis is caused by Listeria monocytogenes(LM) and is currently considered to be one of the leading food-borne diseases worldwide, with mortality rate of 20%~30%. Currently, detection methods for LM are time-consuming with low sensitivity, and delayed detection results. SYTO9 has a high affinity for DNA and exhibits enhanced fluorescence upon binding. Therefore, this study used SYTO9 staining and image processing to develop a rapid loop mediated isothermal amplification(LAMP) detection method for LM. Smartphone was successfully used for detecting the color change in different concentrations of LM. Besides, the optimized LAMP reaction temperature was 63 °C by color identification, and the limit of detection for LM was 6 copies/μL in the green channel. So, the developed method, based on image processing, is simple, sensitive and rapid, which provides a new idea and method for rapid detection of LM and other food-borne bacterial pathogens.

Current signal amplification strategies in aptamer-based electrochemical biosensor:A review

Due to their high specificity and affinity towards various targets,along with other unique advantages such as stability and low cost,aptamers are widely applied in analytical techniques.A typical aptamerbased electrochemical biosensor is composed of a aptamer as the biological recognition element and transducer converting the biologic interaction into electrical signals for the quantitative measurement of targets.Improvement of the sensitivity of a biosensor is significantly important in order to achieve the detection of biomolecules with low abundance,and different amplification strategies have been explored.The strategies either employ nanomaterials such as gold nanoparticles to con struct electrodes which can transfer the biological reactions more efficiently,or attempt to obtain enhanced signal through multi-labeled carriers or utilize enzyme mimics to catalyze redox cycling.This review discusses recent advances in signal amplification methods and their applications.Critical assessment of each method is also considered.

Grey clustering evaluation based on AHP and interval grey number

Purpose–The purpose of this paper is to propose a grey clustering evaluation model based on analytic hierarchy process(AHP)and interval grey number(IGN)to solve the clustering evaluation problem with IGNs.Design/methodology/approach–First,the centre-point triangular whitenisation weight function with real numbers is built,and then by using interval mean function,the whitenisation weight function is extended to IGNs.The weights of evaluation indexes are determined by AHP.Finally,this model is used to evaluate the flight safety of a Chinese airline.The results indicate that the model is effective and reasonable.Findings–When IGN meets certain conditions,the centre-point triangular whitenisation weight function based on IGN is not multiple-cross and it is normative.It provides a certain standard and basis for obtaining the effective evaluation indexes and determining the scientific evaluation of the grey class.Originality/value–The traditional grey clustering model is extended to the field of IGN.It can make full use of all the information of the IGN,so the result of the evaluation is more objective and reasonable,which provides supports for solving practical problems.

Washing-free chemiluminescence immunoassay for rapid detection of cardiac troponin Ⅰ in whole blood samples

Chemiluminescence immunoassay(CLⅠA) has always been a great challenge in detecting cardiac troponin Ⅰ(c Tn Ⅰ) in whole blood samples without centrifugation because of the interference of red blood cells and low sensitivity. Ⅰn this study, the antigens and erythrocytes in the blood were captured by the antibodies immobilized on the magnetic particles, recognized by another biotinconjugated c Tn Ⅰ antibody and detected by streptavidin/acridine aster-conjugated polychloromethylstyrene microspheres(PCMS). After magnetic separation, the supernatant was transferred and measured. No significant difference was noted between the c Tn Ⅰ concentrations of the serum samples,plasma samples and whole blood. The prepared PCMS provided more functional areas to conjugate streptavidin and acridinium ester, so the immunoassay has highly sensitive, the limits of blank at0.012 ng/mL, and functional sensitivity at 0.019 ng/mL with a CV of 20%, and 0.058 ng/mL with a CV of 10%. Total precision of any sample type ranged from 2.62%~5.67%. The assay was linear over the studied range of 0.01-50.00 ng/mL, and no hook effect was found when c Tn Ⅰ concentrations reached 1900 ng/mL. No significant interference was noted with the potential endogenous interfering substances. Compared with the commercial kit(Abbott assay kit), the correlation coefficient was 0.9859. A washing-free CLⅠA was established for the rapid detection of c Tn Ⅰ in human whole blood, using erythrocyte capture antibodies-conjugated magnetic nanoparticles for eliminating the influence of erythrocytes and PCMS for signal amplification, which showed great potential in clinical application.

A microfluidic device for accurate detection of hs-cTnI

This device is aimed at ensuring that the sample is uniformly and equivalently reacted with the antibody on the NC membrane in each test when the microfluidic liquid system is introduced to the chip.In this study,the developed microfluidic chip can avoid the presence of the sample and conjugate pads in the chip,while the precision of the chro matography system can be greatly improved using the same particles,NC membrane and antibody alongside the traditional strip.The results,taking the detection of cTnI as an example,revealed that the coefficient of variation(CV)is controlled within 4%,while the maximum record of the contrast chromatographic reagent strip can reach 15%.Additionally,the detection sensitivity can maintain the same order of magnitudes with that of the traditional chromatographic strip.With the results,the determination correlation of the developed microfluidic chip has been greatly improved.In addition,the CV of the chip in this study is greatly improved in comparison with that of the traditional strip.The biggest improvement lies in the mixing between the sample and the microspheres,indicating that this is a new approach to improve the CV of the traditional strip.

甜蜜的相遇——营养与激素信号协同调节植物生长的新机制

为应对持续不断的环境压力和逆境胁迫,植物需要整合内部和外部信息来调整自身的生长发育,以适应环境。其中,可溶性糖不仅是基础能量和营养代谢的必需分子,也是参与植物生长发育和应对胁迫的信号分子。然而,植物整合糖信号,平衡营养代谢和胁迫应答的分子机制尚不清楚。最近,福建农林大学熊延团队发现,居于植物营养感受通路中心地位的TOR激酶能够直接磷酸化乙烯信号核心组分EIN2蛋白,形成1个葡萄糖-TOR-EIN2的营养感受和调控轴心。植物通过不同的蛋白激酶(TOR和CTR1)精确调控EIN2不同位点的磷酸化,从而使EIN2成为葡萄糖信号和乙烯信号的交叉中心,精巧地调节植物的生长发育。

Discussion of the protein characterization techniques used in the identification of membrane protein targets corresponding to tumor cell aptamers

Aptamer is an oligonucleotide chain with specific binding ability to protein and other targets,which is widely used in ma ny fields.Because of its ability to screen the premise of unknown targets,it can be used to discover some novel tumor markers,i.e.,membrane proteins that are specifically highly expressed on the surface of tumor cells.Tumor markers can be used in many fields such as early diagnosis and treatment,and a new type of tumor marker proved to be effective can significantly improve the therapeutic effect of such tumors.However,further characterization of newly acquired membrane proteins is essential for their clinical use as tumor markers.This review first briefly introduced the process of obtaining novel tumor markers from nucleic acid aptamers.Next,the commonly used protein characterization methods could be used as a technical means to identify membrane protein targets corresponding to tumor cell aptamers,to clarify the principles,advantages and disadvantages of various means,and to analyze the most suitable situations for various experimental methods.Finally,the outlook was made and the characterization methods that should be used in such experiments were summarized.