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Recent advances in CRISPR-based genome editing technology and its applications in cardiovascular research

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Military Medical Research 2023年第6期10卷 862-880页

作者： Zhen-Hua Li Jun wang Jing-ping Xu jian wang Xiao Yang State Key Laboratory of Proteomics Beijing Proteome Research CenterNational Center for Protein SciencesBeijing Institute of LifeomicsBeijing 100071China Yaneng BIOScience(Shenzhen)Co. Ltd.Shenzhen 518102GuangdongChina

The rapid development of genome editing technology has brought major breakthroughs in the fields of life science and medicine. In recent years, the clustered regularly interspaced short palindromic repeats(CRISPR)-based genome editing toolbox has been greatly expanded, not only with emerging CRISPR-associated protein(Cas) nucleases, but also novel applications through combination with diverse effectors. Recently, transposon-associated programmable RNA-guided genome editing systems have been uncovered, adding myriads of potential new tools to the genome editing toolbox. CRISPR-based genome editing technology has also revolutionized cardiovascular research. Here we first summarize the advances involving newly identified Cas orthologs, engineered variants and novel genome editing systems, and then discuss the applications of the CRISPR-Cas systems in precise genome editing, such as base editing and prime editing. We also highlight recent progress in cardiovascular research using CRISPR-based genome editing technologies, including the generation of genetically modified in vitro and animal models of cardiovascular diseases(CVD) as well as the applications in treating different types of CVD. Finally, the current limitations and future prospects of genome editing technologies are discussed.

关键词： Genome editing CRISPR-Cas system Base editing Prime editing Transposon-associated genome editing Cardiovascular disease Heart Blood vessel Gene therapy

Modeling the optimal compensation capacitance of a giant magnetostrictive ultrasonic transducer with a loosely-coupled contactless power transfer system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第10期23卷 757-770页

作者： Tian LAN ping-fa FENG jian-jian wang jian-fu ZHANG Hui-lin ZHOU State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBejing 100084China'China China Ordnance Industry Navigation and Control Technology Research Institute Beijing 10089China

The giant magnetostrictive rotary ultrasonic processing system(GMUPS)with a loosely-coupled contactless power transfer(LCCPT)has emerged as a high-performance technique for the processing of hard and brittle materials,owing to its high power density.A capacitive compensation is required to achieve the highest energy efficiency of GMUPS to provide sufficient vibration amplitude when it works in the resonance state.In this study,an accurate model of the optimal compensation capacitance is derived from a new electromechanical equivalent circuit model of the GMUPS with LCCPT,which consists of an equivalent mechanical circuit and an electrical circuit.The phase lag angle between the mechanical and electrical circuits is established,taking into account the non-negligible loss in energy conversion of giant magnetostrictive material at ultrasonic frequency.The change of system impedance characteristics and the effectiveness of the system compensation method under load are analyzed.Both idle vibration experiments and machining tests are conducted to verify the developed model.The results show that the GMUPS with optimal compensation capacitance can achieve the maximum idle vibration amplitude and smallest cutting force.In addition,the effects of magnetic conductive material and driving voltages on the phase lag angle are also evaluated.

关键词： Rotary ultrasonic machining Giant magnetostrictive transducer(GMT) Loosely-coupled contactless power transfer(LCCPT) Electromechanical equivalent circuit Optimal compensation capacitance

Signal modeling and impulse response shaping for semiconductor detectors

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Nuclear Science and Techniques 2022年第4期33卷 72-82页

作者： Xue-Yuan wang jian-Bin Zhou Ming wang Huai-ping wang Xu Hong Yi Liu ping Huang College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyErxian BridgeNo.1 East 3 RoadChenghua DistrictChengdu 610059China jiangxi Engineering Technology Research Center of Nuclear Geoscience Data Science and System East China University of TechnologyNanchang 330013China China Testing Technology Co. LtdChengdu 610021China

The output-signal models and impulse response shaping(IRS)functions of semiconductor detectors are important for establishing high-precision measurement systems.In this paper,an output-signal model for semiconductor detector systems is proposed.According to the proposed model,a multistage cascade deconvolution IRS algorithm was developed using the C-R inverse system,R-C inverse system,and differentiator system.The silicon drift detector signals acquired from the analog-to-digital converter were tested.The experimental results indicated that the shaped pulses obtained using the proposed model had no undershoot,and the average peak base width of the output shaped pulses was reduced by 36%compared with that for a simple model proposed in a previous work[1].Offline processing results indicated that compared with the traditional IRS algorithm,the average peak base width of the output shaped pulses obtained using the proposed algorithm was reduced by 11%,and the total elapsed time required for pulse shaping was reduced by 26%.The proposed algorithm avoids recursive calculation.If the sampling frequency of the digital system reaches 100 MHz,the proposed algorithm can be simplified to integer arithmetic.The proposed IRS algorithm can be applied to high-resolution energy spectrum analysis,highcounting rate energy spectrum correction,and coincidence and anti-coincidence measurements.

关键词： Output-signal model Impulse response shaping C-R inverse system R-C inverse system Integer arithmetic

Incipient plasticity and activation volume of dislocation nucleation for TiZrNbTaMo high-entropy alloys characterized by nanoindentation

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Journal of Materials Science & Technology 2019年第5期35卷 812-816页

作者： Shao-ping wang jian Xu Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China University of Chinese Academy of Sciences 19(A) Yuquan Road Beijing 100049 China

With instrumented nanoindentation, incipient plasticity of two as-cast BCC TiZrNbTa and TiZrNbTaMo high-entropy alloys(HEAs) are investigated in terms of pop-in events during loading, to characterize the dislocation behavior in these solid-solution alloys. It is shown that the maximum shear stress (max)required for dislocation nucleation is determined to be 1/16-1/12 and 1/18-1/14 of shear modulus for the TiZrNbTa and TiZrNbTaMo HEAs, respectively, which is nearly comparative to the theoretical shear stress of these alloys. The activation volumes of dislocation nucleation the TiZrNbTa and TiZrNbTaMo HEAs are determined to be 1.2 b^3 for and 1.3 b^3, respectively, which is substantially irrespective of alloying with Mo. Furthermore, activation volumes of these two HEAs are on the order of cubic burger’s vector and only one-third of the value for TiZrHfNb HEA, suggesting that a heterogeneous nucleation of dislocation took place in a way of direct atom-vacancy exchange, rather than of the cooperative motion of several atoms. These findings reveal the unique feature in deformation of BCC solid-solution complex alloys.

关键词： High-entropy alloys Nanoindentation Refractory metals BCC phase Incipient plasticity

Evaluation of increasing service life of epoxy zinc-rich coating on 3 wt.%Ni-advanced low-alloy steel in marine atmospheric environment

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Journal of Iron and Steel Research(International) 2022年第4期29卷 698-706页

作者： Sheng-rong wang jian-wei Yang jian-ping Cao Shan jiang Fei-fan Xu Shougang Research Institute of Technology of Shougang Group Co. Ltd.Beijing 100043China Beijing Key Laboratory of Green Recyclable Process for Iron&Steel Production Technology Beijing 100043China

The addition of Ni element into steel to prolong the service life of coated steel was investigated in marine atmospheric environment by laboratory simulated accelerated experiment.The scanning electron microscope and electron probe microanalysis combined with electrochemical impedance spectroscopy were used to characterize coated steel properties and examined the anti-corrosion performance.The results showed that 3 wt.%Ni-advanced steel(3Ni steel)substrate obviously delayed the failure time of coating compared to carbon steel,therefore prolonging the service life of coating on the steel.X-ray diffraction patterns for the corrosion products under the scratched coating on 3Ni steel exhibited that FeNi_(2)O_(4) and Fe_(2)O_(3) occurred in the corrosion product of 3Ni steel.It was also found that Ni element enriched in the product layer through analyzing the appearance and composition of corrosion products by electron probe micro-analysis.Chloride ions were blocked out of product by the enrichment of Ni element in rust layer.

关键词： 3wt.% Ni-advanced low-alloy steel Coating failure Service life Corrosion product Marine atmosphere

Controlling oxygen content in electro-slag remelting steel by optimizing slag-steel reaction process

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China Foundry 2023年第6期20卷 503-510页

作者： Dian-dong Sun Yong wang Lei Jin Zong-xu Pang jian Huang jian-ping Zhang Iron&Steel Research Institutes of Ansteel Group Corporation Anshan 114009LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114009LiaoningChina Shenyang Research Institute of Foundry Co. Ltd.CAMNational Key Laboratory of Advanced Casting TechnologiesShenyang 110022China

The thermodynamic equilibrium of deoxidation reactions between molten slag and steel was calculated using a slag-steel coupling thermodynamic model and the mass conservation model based on the ion-molecular coexistence theory.The study focused on the effects of slag composition and deoxidizer type on the oxygen content of low alloy steel during the electroslag remelting(ESR)process.The measured and predicted values of the oxygen content in remelted ingots,and the contents of FeO and MnO in slags were compared and analyzed.Results show that the measured content of total oxygen has a certain correlation with the trend of dissolved oxygen predicted by the model when using Ca-Si alloys as deoxidizer,but it is not correlated with the trend of dissolved oxygen predicted by the model when using Al as deoxidizer.The deoxidation mechanisms of Ca-Si and Al are different.Ca-Si alloy directly reacts with FeO and MnO in slag to reduce the oxygen potential of slag,hence it can inhibit the transfer of oxygen from the slag to molten steel.While,when Al deoxidizer is used,the oxygen content in steel is mainly reduced through floating up the alumina inclusions.Compared to Al,utilizing Ca-Si alloy as a deoxidizer is more effective in reducing the oxygen content and the amount of inclusions in ESR ingot.

关键词： ion-molecular coexistence theory slag-steel reaction deoxidation electro-slag remelting

Denaturation behavior of inclusions in industrial pure iron by calcium treatment

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Journal of Iron and Steel Research(International) 2023年第2期30卷 249-258页

作者： Xin Liu Yan-ping Bao Cheng-jian Hua jian-hua Chu Chao Gu Min wang State Key Lab of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

Only a few Chinese enterprises can produce high-quality industrial pure iron,and studies on the smelting process of industrial pure iron were limited.The inclusions in a melting process were characterized by means of electron microscopy and an automatic inclusion analysis system,and the evolution mechanism of inclusion was studied using thermodynamic calculation to optimize the calcium alloy addition in liquid window.The results show that during the smelting process,inclusions mainly composed of Al_(2)O_(3)and spinel are formed before calcium treatment.After calcium treatment,they continuously react with[Ca],[S]and[Ti],grow up,and are removed during refining and tundish pouring.In the end,there are more small-sized inclusions containing CaS,and the contents of Al_(2)O_(3)and spinel are less.According to thermodynamic calculations,the appropriate calcium treatment liquid window for the molten steel composition is(10-38)×10^(-6).Calcium treatment has changed the main types of inclusions in industrial pure iron from Al_(2)O_(3)to small-sized inclusions containing CaS and effectively reduces the influence of Al_(2)O_(3)inclusions on the quality of industrial pure iron.

关键词： Industrial pure iron Calcium treatment Inclusion Thermodynamic CaS

A simple and successful treatment for rupture and defect of the posterior third superior sagittal sinus caused by open depressed skull fracture:A case report

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Chinese Journal of Traumatology 2022年第2期25卷 115-117页

作者： Geng-Huan wang He-ping Shen Zheng-Min Chu jian-Guo Shen jian Shen Department of Neurosurgery The Second Affiliated Hospital of Jiaxing UniversityJiaxing314000Zhejiang ProvinceChina

It is extremely dangerous to treat the posterior third of the superior sagittal sinus (PTSSS) surgically, since it is usually not completely ligated. In this report, the authors described the case of a 27-year-old man with a ruptured and defective PTSSS caused by an open depressed skull fracture, which was treated by ligation of the PTSSS and the patient achieved a positive recovery. The patient's occiput was hit by a height-limiting rod and was in a mild coma. A CT scan showed an open depressed skull fracture overlying the PTSSS and a diffuse brain swelling. He underwent emergency surgery. When the skull fragments were removed, a 4 cm segment of the superior sagittal sinus (SSS) and the adjacent dura mater were removed together with bone fragments. Haemorrhage occurred and blood pressure dropped. We completed the operation by ligating the severed ends of the fractured sagittal sinus. One month after the operation, apart from visual field defects, he recovered well. In our opinion, in primary hospitals, when patients with severely injured PTSSS cannot sustain a long-time and complicated operation, e.g., the bypass using venous graft, and face life-threatening conditions, ligation of the PTSSS is another option, which may unexpectedly achieve good results.

关键词： Depressed skull fracture Superior sagittal sinus Ligation Prognoses

Effect of quenching-partitioning treatment on the microstructure, mechanical and abrasive properties of high carbon steel

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 676-687页

作者： jian-ping Lai Jia-xin Yu Jiong wang Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education Mianyang 621010China School of Manufacturing Science and Engineering Southwest University of Science and TechnologyMianyang 621010China Central Sichuan Oil-Gas District Petro-China Southwest Oil and Gas Field CompanySuining 629000China

The present work employed the X-ray diffraction, scanning electron microscopy, electron backscattered diffraction, and electron probe microanalysis techniques to identify the microstructural evolution and mechanical and abrasive behavior of high carbon steel during quenching-partitioning treatment with an aim to enhance the toughness and wear resistance of high carbon steel.Results showed that, with the increase in partitioning temperature from 250 to 400℃, the amount of retained austenite(RA) decreased resulting from the carbide precipitation effect after longer partitioning times.Moreover, the stability of RA generally increased because of the enhanced degree of carbon enrichment in RA.Given the factors affecting the toughness of high carbon steel, the stability of RA associated with size, carbon content, and morphology plays a significant role in determining the toughness of high carbon steel.The analysis of the wear resistance of samples with different mechanical properties shows that hardness is the primary factor affecting the wear resistance of high carbon steel, and the toughness is the secondary one.

关键词： high carbon steel quenching and partitioning microstructural evolution retained austenite