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Science China Chemistry 2024年第7期67卷 2325-2334页

作者： Xue Li Meng Kai Xu Yuan Huang tao cai Key Laboratory of Biomedical Polymers of Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518057China

Despite the challenges that remain,the synergistic adjustment of various microstructures and photochemical parameters of graphitic carbon nitride(g-C_(3)N_(4))in photocatalytic reactions holds promises for improving catalytic efficiency and reducing energy consumption.Herein,sulfur-doped and nitrogen-defective g-C_(3)N_(4)(n-SC_(3)N_(x))nanosheets were designed and elaborately synthesized.The resultant n-SC_(3)N_(x)possessed a precisely defined 2D layer structure with extensive porosity and incremental specific surface area.Enhanced photoinduced electron transfer-reversible addition-fragmentation chain transfer(PET-RAFT)polymerization of vinyl monomers with low dispersity,excellent temporal control and high chain-end fidelity was achieved under mild blue light irradiation in a nondegassed system.Owing to their ultrathin nanostructures with nitrogen defects and sulfur dopants,n-SC_(3)N_(x)was capable of catalyzing RAFT polymerization in aqueous solutions at significantly accelerated rates,which were nearly 8 times faster compared to bulk g-C_(3)N_(4).The ease of separation and efficient reusability in subsequent polymerizations was enabled by the heterogeneous nature of n-SC_(3)N_(x).The appeal of this approach was illustrated by the fact that utilizing a reusable and metal-free photocatalyst in aqueous environments allowed for the synthesis of polymers with molecular weight up to 300 kg mol-1and a dispersity of 1.32.

关键词： graphitic carbon nitride nitrogen defects sulfur dopants PET-RAFT polymerization recyclability

NEHASH:high-concurrency extendible hashing for non-volatile memory

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Frontiers of Information Technology & Electronic Engineering 2023年第5期24卷 703-715页

作者： tao cai Pengfei GAO Dejiao NIU Yueming MA Tianle LEI Jianfei DAI School of Computer Science and Communication Engineering Jiangsu UniversityZhenjiang 212013China

Extendible hashing is an effective way to manage increasingly large file system metadata,but it suffers from low concurrency and lack of optimization for non-volatile memory(NVM).In this paper,a multilevel hash directory based on lazy expansion is designed to improve the concurrency and efficiency of extendible hashing,and a hash bucket management algorithm based on groups is presented to improve the efficiency of hash key management by reducing the size of the hash bucket,thereby improving the performance of extendible hashing.Meanwhile,a hierarchical storage strategy of extendible hashing for NVM is given to take advantage of dynamic random access memory(DRAM)and NVM.Furthermore,on the basis of the device driver for Intel Optane DC Persistent Memory,the prototype of high-concurrency extendible hashing named NEHASH is implemented.Yahoo cloud serving benchmark(YCSB)is used to test and compare with CCEH,level hashing,and cuckoo hashing.The results show that NEHASH can improve read throughput by up to 16.5%and write throughput by 19.3%.

关键词： Extendible hashing Non-volatile memory(NVM) High concurrency

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独立游戏开发者:坚守创造梦

The World of Chinese 2024年第1期 92-98页

作者： Roman Kierst cai tao 不详

Indie video game developers risk it all for creative and commercial success in an ultracompetitive industry独立游戏开发者:在激烈的行业竞争中坚守创作梦To make his latest video game,Yang Yi had to sell his house.After his previous game had its launch delayed by a licensing freeze in China’s game market in 2018,then suffered poor sales after its final release in 2020,Yang and his small team were in a“pretty dire”financial situation,he says.They had to take on external software development gigs to stay afloat before they ran out of money completely in 2021.

关键词： money competitive float

Directed evolution of a neutrophilic and mesophilic methanol dehydrogenase based on high-throughput and accurate measurement of formaldehyde

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Synthetic and Systems Biotechnology 2023年第3期8卷 386-395页

作者： Jin Qian Liwen Fan Jinxing Yang Jinhui Feng Ning Gao Guimin Cheng Wei Pu Wenjuan Zhou tao cai Shuang Li Ping Zheng Jibin Sun Depei Wang Yu Wang College of Biotechnology Tianjin University of Science and TechnologyTianjin300222China Haihe Laboratory of Synthetic Biology Tianjin300308China Key Laboratory of Engineering Biology for Low-carbon Manufacturing Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308China National Technology Innovation Center of Synthetic Biology Tianjin300308China University of Chinese Academy of Sciences Beijing100049China School of Biology and Biological Engineering South China University of TechnologyGuangzhou510006China

Methanol is a promising one-carbon feedstock for biomanufacturing,which can be sustainably produced from carbon dioxide and natural gas.However,the efficiency of methanol bioconversion is limited by the poor catalytic properties of nicotinamide adenine dinucleotide(NAD^(+))-dependent methanol dehydrogenase(Mdh)that oxidizes methanol to formaldehyde.Herein,the neutrophilic and mesophilic NAD^(+)-dependent Mdh from Bacillus stearothermophilus DSM 2334(Mdh_(Bs))was subjected to directed evolution for enhancing the catalytic activity.The combination of formaldehyde biosensor and Nash assay allowed high-throughput and accurate measurement of formaldehyde and facilitated efficient selection of desired variants.Mdh_(Bs)variants with up to 6.5-fold higher K_(cat)/K_(M)value for methanol were screened from random mutation libraries.The T153 residue that is spatially proximal to the substrate binding pocket has significant influence on enzyme activity.The beneficial T153P mutation changes the interaction network of this residue and breaks theα-helix important for substrate binding into two shortα-helices.Reconstructing the interaction network of T153 with surrounding residues may represent a promising strategy to further improve Mdh_(Bs),and this study provides an efficient strategy for directed evolution of Mdh.

关键词： Methanol dehydrogenase Formaldehyde biosensor Directed evolution C1 bioconversion Methanol oxidation Methylotrophy

MBRidge: an accurate and cost-effective method for profiling DNA methylome at single-base resolution

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分子细胞生物学报:英文版 2015年第4期7卷 299-313页

作者： Wanshi cai Fengbiao Mao Huajing Teng tao cai Fangqing Zhao Jinyu Wu Zhong Sheng Sun Beijing Institutes of Life Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute of Zoology Chinese Academy of SciencesBeijing 100101China Experimental Medicine Section NIDCRNational Institutes of HealthBethesdaMD 20892USA Institute of Genomic Medicine Wenzhou Medical UniversityWenzhou 325035China

Organisms and cells,in response to environmental influences or during development,undergo considerable changes in DNA methylation on a genome-wide scale,which are linked to a variety of biological processes.Using MethylC-seq to decipher DNA methylome at single-base resolution is prohibitively costly.In this study,we develop a novel approach,named MBRidge,to detect the methylation levels of repertoire CpGs,by innovatively introducing C-hydroxylmethylated adapters and bisulfate treatment into the MeDIP-seq protocol and employing ridge regression in data analysis.A systematic evaluation of DNA methylome in a human ovarian cell line T29 showed that MBRidge achieved high correlation(R>0.90)with much less cost(∼10%)in comparison with MethylC-seq.We further applied MBRidge to profiling DNA methylome in T29H,an oncogenic counterpart of T29’s.By comparing methylomes of T29H and T29,we identified 131790 differential methylation regions(DMRs),which are mainly enriched in carcinogenesis-related pathways.These are substantially different from7567 DMRs that were obtained by RRBS and related with cell development or differentiation.The integrated analysis ofDMRsin the promoterand expression of DMR-corresponding genes revealed thatDNAmethylation enforced reverse regulation of gene expression,depending on the distance fromthe proximalDMRto transcription starting sites in both mRNA and lncRNA.Taken together,our results demonstrate that MBRidge is an efficient and cost-effective method that can be widely applied to profiling DNA methylomes.

关键词： DNA methylome MB-seq ridge regression single-base resolution

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大世界小剧场:丁衍庸的晚年“戏画”

美术学报 2024年第1期 35-45页

作者：蔡涛广州美术学院艺术与人文学院

本文关注了丁衍庸晚年在香港地区创作的神鬼题材的水墨画。这些题材新颖多变的画作,一方面反映了他所追求的以“神趣”为要旨的文化自觉和境界升华,同时也让人联想到艺术家披沥的世变沧桑,反映为一种“晚期风格”,尤其在艺术家心理创伤... 详细信息

本文关注了丁衍庸晚年在香港地区创作的神鬼题材的水墨画。这些题材新颖多变的画作,一方面反映了他所追求的以“神趣”为要旨的文化自觉和境界升华,同时也让人联想到艺术家披沥的世变沧桑,反映为一种“晚期风格”,尤其在艺术家心理创伤的层面上,可被视为一种深有意味的癫狂。擅长野兽派画风的丁衍庸,此时对八大山人的大写意画风进行了创造性融合,以一种人鬼神之际、东西洋之交的新颖“戏画”,演绎出一幕幕“大世界小剧场”。而丁氏的晚年“戏画”,在中国现代美术史上占据的重要位置,尚未获得应有的评价。

关键词：丁衍庸野兽派八大山人晚年“戏画” 神鬼题材

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赣深高速铁路桥上半封闭式声屏障设计

工程建设与设计 2024年第7期 112-115页

作者：蔡涛中铁第四勘察设计院集团有限公司武汉430063

赣深高铁涉及深圳市城市建成区,结合城区路段噪声敏感建筑物以及环评降噪要求,对半封闭式声屏障从梁型、结构型式、安装方式等方面进行研究,以期选择最佳的半封闭声屏障,为高速铁路采用半封闭声屏障降噪设计提供了实际工程案例,为后续... 详细信息

赣深高铁涉及深圳市城市建成区,结合城区路段噪声敏感建筑物以及环评降噪要求,对半封闭式声屏障从梁型、结构型式、安装方式等方面进行研究,以期选择最佳的半封闭声屏障,为高速铁路采用半封闭声屏障降噪设计提供了实际工程案例,为后续解决高速铁路城区段噪声问题提供了借鉴。

关键词：高速铁路半封闭式声屏障降噪设计

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Climate change characteristics of Amur River

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Water Science and Engineering 2013年第2期6卷 131-144页

作者： Lan-lan YU Zi-qiang XIA Jing-ku LI tao cai River Basin Authority of Liaoning Province State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Institute of International Rivers Research Academy Hohai University Hydrological Bureau of Liaoning Province

Unusually severe weather is occurring more frequently due to global climate change. Heat waves, rainstorms, snowstorms, and droughts are becoming increasingly common all over the world, threatening human lives and property. Both temperature and precipitation are representative variables usually used to directly reflect and forecast the influences of climate change. In this study, daily data （from 1953 to 1995） and monthly data （from 1950 to 2010） of temperature and precipitation in five regions of the Amur River were examined. The significance of changes in temperature and precipitation was tested using the Mann-Kendall test method. The amplitudes were computed using the linear least-squares regression model, and the extreme temperature and precipitation were analyzed using hydrological statistical methods. The results show the following： the mean annual temperature increased significantly from 1950 to 2010 in the five regions, mainly due to the warming in spring and winter; the annual precipitation changed significantly from 1950 to 2010 only in the lower mainstream of the Amur River; the frequency of extremely low temperature events decreased from 1953 to 1995 in the mainstream of the Amur River; the frequency of high temperature events increased from 1953 to 1995 in the mainstream of the Amur River; and the frequency of extreme precipitation events did not change significantly from 1953 to 1995 in the mainstream of the Amur River. This study provides a valuable theoretical basis for settling disputes between China and Russia on sustainable development and utilization of water resources of the Amur River.

关键词： climate change temperature precipitation extreme weather events Mann-Kendall test method,＂ linear least-squares regression model,＂ Amur River

Novel MSX1 variants identified in families with nonsyndromic oligodontia

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International Journal of Oral Science 2021年第1期13卷 42-51页

作者： Jinglei Zheng Miao Yu Haochen Liu tao cai Hailan Feng Yang Liu Dong Han Department of Prosthodontics Peking University School and Hospital of Stomatology&National Engineering Laboratory for Digital and Material Technology of Stomatology&Beijing Key Laboratory of Digital StomatologyBeijingChina National Institute of Dental and Craniofacial Research NIHBethesdaMDUSA

The goal of this study was to identify MSX1 gene variants in multiple Chinese families with nonsyndromic oligodontia and analyse the functional influence of these variants.Whole-exome sequencing(WES)and Sanger sequencing were performed to identify the causal gene variants in five families with nonsyndromic oligodontia,and a series of bioinformatics databases were used for variant confirmation and functional prediction.Phenotypic characterization of the members of these families was described,and an in vitro analysis was performed for functional evaluation.Five novel MSX1 heterozygous variants were identified:three missense variants[c.662A>C(p.Q221P),c.670C>T(p.R224C),and c.809C>T(p.S270L)],one nonsense variant[c.364G>T(p.G122*)],and one frameshift variant[c.277delG(p.A93Rfs*67)].Preliminary in vitro studies demonstrated that the subcellular localization of MSX1 was abnormal with the p.Q221P,p.R224C,p.G122*,and p.A93Rfs*67 variants compared to the wild type.Three variants(p.Q221P,p.G122*,and p.A93Rfs*67)were classified as pathogenic or likely pathogenic,while p.S270L and p.R224C were of uncertain significance in the current data.Moreover,we summarized and analysed the MSX1-related tooth agenesis positions and found that the type and variant locus were not related to the severity of tooth loss.Our results expand the variant spectrum of nonsyndromic oligodontia and provide valuable information for genetic counselling.

关键词： MSX1 variants likely

RANS simulations on combustion and emission characteristics of a premixed NH_(3)/H_(2) swirling flame with reduced chemical kinetic model

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Chinese Journal of Aeronautics 2021年第12期34卷 17-27页

作者： Yuze SUN tao cai Mohammad SHAHSAVARI Dakun SUN Xiaofeng SUN Dan ZHAO Bing WANG Department of Mechanical Engineering University of CanterburyChristchurch 8041New Zealand School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Collaborative Innovation Center for Advanced Aero-Engine Beihang UniversityBeijing 100083China

Ammonia(NH_(3))is considered as a potential alternative carbon free fuel to reduce greenhouse gas emission to meet the increasingly stringent emission requirements.Co-burning NH_(3) and H_(2) is an effective way to overcome ammonia’s relative low burning velocity.In this work,3D Reynolds Averaged Navier-Stokes(RANS)numerical simulations are conducted on a premixed NH_(3)/H_(2) swirling flame with reduced chemical kinetic mechanism.The effects of(A)overall equivalence ratio Φ and(B)hydrogen blended molar fraction XH2 on combustion and emission characteristics are examined.The present results show that when 100%NH_(3)-0%H_(2)-air are burnt,the NO emission and unburned NH3 of at the swirling combustor outlet has the opposite varying trends.With the increase of Φ,NO emission is found to be decreased,while the unburnt ammonia emission is increased.NH_(2)→HNO,NH→HNO and HNO→NO sub-paths are found to play a critical role in NO formation.Normalized reaction rate of all these three sub-paths is shown to be decreased with increased Φ.Hydrogen addition is shown to significantly increase the laminar burning velocity of the mixed fuel.However,adding H_(2) does not affect the critical equivalence ratio corresponding to the maximum burning velocity.The emission trend of NO and unburnt NH_(3) with increased Φ is unchanged by blending H_(2).NO emission with increased X_(H2) is increased slightly less at a larger Φ than that at a smaller Φ.In addition,reaction rates of NH_(2)→HNO and HNO→NO sub-paths are decreased with increased X_(H2),when Φ is larger.Under all tested cases,blending H_(2) with NH_(3) reduces the unburned NH_(3) emission,especially for rich combustion conditions.In summary,the present work provides research finding on supporting applying ammonia with hydrogen blended in low-emission gas turbine engines.

关键词： Ammonia Emission Hydrogen Premixed combustion Reduced mechanism Swirling flame