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A low-cost and high-performance technique for adaptive optics static wavefront correction

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Research in Astronomy and Astrophysics 2021年第7期21卷 261-268页

作者： De-Qing ren tian-yu Zhang Gang Wang California State University Northridge Department of Physics and AstronomyNorthridgeCA 91330USA National Astronomical Observatories/Nanjing Institute of Astronomical Optics and Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics and Technology Nanjing Institute of Astronomical Optics and TechnologyNanjing 210042China University of Chinese Academy of Sciences Beijing 100049China

Non-Common Path Error(NCPE) is one of the factors that limit an Adaptive Optics(AO)system from delivering ultra-high performance. To correct the NCPE associated static aberration, we propose a simple but robust and high-performance pupil-plane based wavefront measurement and correction technique, which can copy a single-mode fiber generated perfect wavefront to the AO system via an iteration optimization process, and the NCPE can be effectively corrected by directly commanding the Deformable Mirror(DM) of the AO system. Compared with the previous focal-plane based approach that uses focal plane based Point Spread Function(PSF) for correction evaluation, the pupil-plane based approach can be reliably and rapidly converged to a global optimization result and provides better performance, in particular for an AO system with a large initial static wavefront error. This technique we proposed can be implemented in astronomical AO systems where extremely high performance is required.

关键词： astronomical instrumentation:adaptive optics astronomical instrumentation:high angular resolution astronomical techniques:high angular resolution

Significantly enhanced energy density of nanodiamond/polyimide composites at high temperatures with ultralow nanodiamond contents

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Science China(Technological Sciences) 2023年第4期66卷 956-965页

作者： WANG ChengWei CAO XiaoDan tian Junyuan yu Fang JIANG FengYing ren KaiLiang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBejing 100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBejing 100049China Center on Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNaning 530004China

The development of miniature devices has generated a large demand for dielectric polymers with high energy storage density,especially at high temperatures.First,poly(methyl methacrylate)(PMMA)-coated nanodiamond(ND)particles were incorporated into a polyimide(PI)substrate to fabricate ND-g-PMMA/PI(NPP)composites.We found for the first time that with a very low content(0.4 vol.%)of ND particles,NPP-0.4 composite material gave the dielectric constant of 4.4,which is 37.5%higher than that of the PI film.The maximum energy density of the NPP-0.4 composite film achieves 9.4 J cm^(-3)at room temperature,which is 54%higher than that of the PI film.Furthermore,we found that the NPP-0.2 composite reaches the highest energy density and discharge efficiency of 5.77 J cm^(-3)and 72.3%at 150℃,which are 104%and 51.3%higher than those of the PI film at 150℃.This result shows a much higher energy density than most previously published results for high-temperature polymer capacitors.This phenomenon can be explained by the simulation results using COMSOL in which the interface polarization of ND/PI composites reached their maximum value with ultralow ND contents(0.4 vol.%).This research shows great promise for polymer capacitors with relatively high energy density at high temperatures.

关键词： energy storage high-temperature capacitor nanodiamond interface polarization

FOXA1 in prostate cancer

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Asian Journal of Andrology 2023年第3期25卷 287-295页

作者： Hui-yu Dong Lei Ding tian-ren Zhou Tao Yan Jie Li Chao Liang Department of Urology The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Department of Clinical Medicine Suzhou Vocational Health CollegeSuzhou 215009China

Most prostate cancers initially respond to androgen deprivation therapy(ADT).With the long-term application of ADT,localized prostate cancer will progress to castration-resistant prostate cancer(CRPC),metastatic CRPC(mCRPC),and neuroendocrine prostate cancer(NEPC),and the transcriptional network shifted.Forkhead box protein A1(FOXA1)may play a key role in this process through multiple mechanisms.To better understand the role of FOXA1 in prostate cancer,we review the interplay among FOXA1-targeted genes,modulators of FOXA1,and FOXA1 with a particular emphasis on androgen receptor(AR)function.Furthermore,we discuss the distinct role of FOXA1 mutations in prostate cancer and clinical significance of FOXA1.We summarize possible regulation pathways of FOXA1 in different stages of prostate cancer.We focus on links between FOXA1 and AR,which may play different roles in various types of prostate cancer.Finally,we discuss FOXA1 mutation and its clinical significance in prostate cancer.FOXA1 regulates the development of prostate cancer through various pathways,and it could be a biomarker for mCRPC and NEPC.Future efforts need to focus on mechanisms underlying mutation of FOXA1 in advanced prostate cancer.We believe that FOXA1 would be a prognostic marker and therapeutic target in prostate cancer.

关键词： androgen receptor forkhead box protein A1 mutation prostate cancer

Recent progress in bio-inspired macrostructure array materials with special wettability—from surface engineering to functional applications

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International Journal of Extreme Manufacturing 2024年第1期6卷 208-256页

作者： Zhongxu Lian Jianhui Zhou Wanfei ren Faze Chen Jinkai Xu Yanling tian Huadong yu School of Mechanical and Aerospace Engineering Jilin UniversityChangchun 130022People’s Republic of China Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing Changchun University of Science and TechnologyChangchun 130022People’s Republic of China College of Mechanical and Electrical Engineering Changchun University of Science and TechnologyChangchun 130022People’s Republic of China School of Mechanical Engineering Tianjin UniversityTianjin 300350People’s Republic of China School of Engineering University of WarwickCoventry CV47ALUnited Kingdom

Bio-inspired macrostructure array(MAA,size:submillimeter to millimeter scale)materials with special wettability(MAAMs-SW)have attracted significant research attention due to their outstanding performance in many applications,including oil repellency,liquid/droplet manipulation,anti-icing,heat transfer,water collection,and oil–water separation.In this review,we focus on recent developments in the theory,design,fabrication,and application of bio-inspired MAAMs-SW.We first review the history of the basic theory of special wettability and discuss representative structures and corresponding functions of some biological surfaces,thus setting the stage for the design and fabrication of bio-inspired MAAMs-SW.We then summarize the fabrication methods of special wetting MAAs in terms of three categories:additive manufacturing,subtractive manufacturing,and formative manufacturing,as well as their diverse functional applications,providing insights into the development of these MAAMs-SW.Finally,the challenges and directions of future research on bio-inspired MAAMs-SW are briefy addressed.Worldwide efforts,progress,and breakthroughs from surface engineering to functional applications elaborated herein will promote the practical application of bio-inspired MAAMs-SW.

关键词： macrostructure arrays superhydrophobic 3D printing laser droplet manipulation

Recent advances in isolation,identification,and culture of mammalian spermatogonial stem cells

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Asian Journal of Andrology 2022年第1期24卷 5-14页

作者： Hua-Ming Xi Yi-Jie ren Fa ren yu Li tian-yu Feng Zhi Wang Ye-Qing Du Li-Kun Zhang Jian-Hong Hu Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest Agriculture and Forestry UniversityYangling 712100China

Continuous spermatogenesis depends on the self-renewal and differentiation of spermatogonial stem cells(SSCs).SSCs,the only male reproductive stem cells that transmit genetic material to subsequent generations,possess an inherent self-renewal ability,which allows the maintenance of a steady stem cell pool.SSCs eventually differentiate to produce sperm.However,in an in vitro culture system,SSCs can be induced to differentiate into various types of germ cells.Rodent SSCs are well defined,and a culture system has been successfully established for them.In contrast,available information on the biomolecular markers and a culture system for livestock SSCs is limited.This review summarizes the existing knowledge and research progress regarding mammalian SSCs to determine the mammalian spermatogenic process,the biology and niche of SSCs,the isolation and culture systems of SSCs,and the biomolecular markers and identification of SSCs.This information can be used for the effective utilization of SSCs in reproductive technologies for large livestock animals,enhancement of human male fertility,reproductive medicine,and protection of endangered species.

关键词： culture identification isolation male germline stem cell spermatogonial stem cell transplantation

Heteroatom-Induced Accelerated Kinetics on Nickel Selenide for Highly Efficient Hydrazine-Assisted Water Splitting and Zn-Hydrazine Battery

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Nano-Micro Letters 2023年第9期15卷 492-504页

作者： Hao-yu Wang Lei Wang Jin-Tao ren Wen-Wen tian Ming-Lei Sun Zhong-Yong yuan School of Materials Science and Engineering Smart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300350People’s Republic of China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071People’s Republic of China

Hydrazine-assisted water electrolysis is a promising energy conversion technology for highly efficient hydrogen production.Rational design of bifunctional electrocatalysts,which can simultaneously accelerate hydrogen evolution reaction(HER)/hydrazine oxidation reaction(HzOR)kinetics,is the key step.Herein,we demonstrate the development of ultrathin P/Fe co-doped NiSe_(2) nanosheets supported on modified Ni foam(P/Fe-NiSe_(2)) synthesized through a facile electrodeposition process and subsequent heat treatment.Based on electrochemical measurements,characterizations,and density functional theory calculations,a favorable“2+2”reaction mechanism with a two-step HER process and a two-step HzOR step was fully proved and the specific effect of P doping on HzOR kinetics was investigated.P/Fe-NiSe_(2) thus yields an impressive electrocatalytic performance,delivering a high current density of 100 mA cm^(−2) with potentials of−168 and 200 mV for HER and HzOR,respectively.Additionally,P/Fe-NiSe_(2) can work efficiently for hydrazine-assisted water electrolysis and Zn-Hydrazine(Zn-Hz)battery,making it promising for practical application.

关键词： Water electrolysis Hydrogen production Hydrazine oxidation Bifunctional electrocatalyst Heteroatom doping

Transfer of disulfide bond formation modules via yeast artificial chromosomes promotes the expression of heterologous proteins inKluyveromyces marxianus

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mLife 2024年第1期3卷 129-142页

作者： Pingping Wu Wenjuan Mo tian tian Kunfeng Song Yilin Lyu Haiyan ren Jungang Zhou Yao yu Hong Lu State Key Laboratory of Genetic Engineering School of Life SciencesFudan UniversityShanghaiChina Shanghai Engineering Research Center of Industrial Microorganisms ShanghaiChina

Kluyveromyces marxianus is a food-safe yeast with great potential for producing heterologous proteins.Improving the yield in K.marxianus remains a challenge and incorporating large-scale functional modules poses a technical obstacle in engineering.To address these issues,linear and circular yeast artificial chromosomes of K.marxianus(KmYACs)were constructed and loaded with disulfide bond formation modules from Pichia pastoris or K.marxianus.These modules contained up to seven genes with a maximum size of 15 kb.KmYACs carried telomeres either from K.marxianus or Tetrahymena.KmYACs were transferred successfully into K.marxianus and stably propagated without affecting the normal growth of the host,regardless of the type of telomeres and configurations of KmYACs.KmYACs increased the overall expression levels of disulfide bond formation genes and significantly enhanced the yield of various heterologous proteins.In high-density fermentation,the use of KmYACs resulted in a glucoamylase yield of 16.8 g/l,the highest reported level to date in K.marxianus.Transcriptomic and metabolomic analysis of cells containing KmYACs suggested increased flavin adenine dinucleotide biosynthesis,enhanced flux entering the tricarboxylic acid cycle,and a preferred demand for lysine and arginine as features of cells overexpressing heterologous proteins.Consistently,supplementing lysine or arginine further improved the yield.Therefore,KmYAC provides a powerful platform for manipulating large modules with enormous potential for industrial applications and fundamental research.Transferring the disulfide bond formation module via YACs proves to be an efficient strategy for improving the yield of heterologous proteins,and this strategy may be applied to optimize other microbial cell factories.

关键词： disulfide bond formation expression of heterologous proteins Kluyveromyces marxianus telomere yeast artificial chromosome

Operation of silicon-germanium heterojunction bipolar transistors with different structures at deep cryogenic temperature

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Science Bulletin 2019年第7期64卷 469-477页

作者： Guofang yu renrong Liang Xiawa Wang Jun Xu tian-Ling ren Institute of Microelectronics Tsinghua University Beijing National Research Center for Information Science and Technology (BNRist) Tsinghua University

In this work, the device performances of discrete and integrated SiGe heterojunction bipolar transistors(HBTs) with different device structures from 300 to 4.8 K were investigated. The turn-on voltages of baseemitter and base-collector junctions increased non-linearly with temperature cooled to 4.8 K. Energy bandgap engineering was taken into account for the analytical model of the turn-on voltage versus temperature. Incomplete ionization occurred in the base-collector junction because of the low doping concentration. The trap-assisted tunneling current in the forward base current was clearly observed below20 K. The ideality factor and saturation current were shown to be temperature dependence. The ideality factor was much larger than 2 below 40 K, indicating that the current is not only contributed by drift, diffusion and recombination, but also by tunneling. The peak current gain of the discrete SiGe HBTs achieved the maximum value of 3,388 at 80 K, while that of the integrated was 546 at 140 K. The transconductance in logarithm was linearly dependent on reciprocal temperature above 50 K, but flattened below 50 K.Early effect was evidently observed below 77 K in the fixed base current output characteristics of the discrete SiGe HBTs, and it was not obvious for the integrated SiGe HBTs.

关键词： SiGe HBTs Quantum computing Cryogenic temperature Analytical model

Extractive desulfurization of model fuels with a nitrogen-containing heterocyclic ionic liquid

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Frontiers of Chemical Science and Engineering 2022年第12期16卷 1735-1742页

作者： Guojia yu Dongyu Jin Xinyu Li Fan Zhang Shichao tian Yixin Qu Zhiyong Zhou Zhongqi ren College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

A nitrogen-containing ionic liquid was synthesized using an aromatic nitrogen-containing heterocyclic and an amino acid,and applied to the extractive desulfurization process to remove benzothiophene,dibenzothiophene,and 4,6-dimethyldibenzothiphene from a model fuel oil.Chemical characterizations and simulation using Gaussian 09 software confirmed the rationality of an ionic liquid structure.Classification of non-covalent interactions between the ionic liquid and the three sulfur-containing contaminants was studied by reduced density gradient analysis.The viscosity of the ionic liquid was adjusted by addition of polyethylene glycol.Under extraction conditions of the volume of ionic liquid to oil as 1:1 and temperature as room temperature,the desulfurization selectivity of ionic liquid followed the order of 4,6-dimethyldibenzothiphene(15 min)

关键词： extractive desulfurization nitrogen-containing heterocyclic ionic liquid reduced density gradient analysis desulfurization selectivity