检索结果-南通市图书馆

Computational protein design and structure prediction——the 2024 Nobel prize in chemistry

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第3期 812-814页

作者： Peilong Lu Lei Liu School of Life Sciences and Research center for Industries of the Future Westlake University Tsinghua-Peking Joint center for Life Sciences Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyCenter for Synthetic and Systems BiologyDepartment of ChemistryTsinghua University

The 2024 Nobel prize in chemistry recognizes groundbreaking advancements in protein science,highlighting the power of artificial intelligence(AI) to decipher and design the molecular machinery of *** of the prize was awarded to David Baker for the computational design of proteins;the other to Demis Hassabis and John Jumper for their AI-driven predictions of protein structures.

关键词：

同方期刊数据库

Convergent and conserved roads lead to Rome: now archaea fill the gap of transcription termination

在线全文

学校读者我要写书评

暂无评论

Science China Life Sciences 2025年

作者： Ning Song Meng Li Archaeal biology center Synthetic Biology Research Center Shenzhen Key Laboratory of Marine Microbiome Engineering Key Laboratory of Marine Microbiome Engineering of Guangdong Higher Education Institutes Institute for Advanced Study Shenzhen University

Transcription termination is a crucial step in gene expression and is pivotal for the accurate completion of mRNA *** bacteria and eukaryotes employ distinct regulatory mechanisms for this process, intriguing parallels exist. In bacteria, transcription termination occurs via two primary mechanisms:the intrinsic (Rho-independent) and the Rho-dependent pathways. The intrinsic pathway hinges on the formation of a hairpin loop by specific RNA sequences and the following poly(U) sequence, which prompts the release of the nascent RNA and the detachment of RNA polymerase(RNAP) from DNA (You et al., 2023).

关键词：

Two paths, one goal: mechanism of calcium homeostasis to balance plant growth and immunity

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2025年第1期68卷 306-308页

作者： Aziz Ul Ikram Yanping Jing Huan Chen Jian Chen International Genome center Jiangsu UniversityZhenjiang 212013China Joint center for Single Cell biology School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China

Calcium(Ca^(2+))is an essential nutrient and a cellular signal in *** level of free Ca^(2+)in the apoplast is~10,000-fold higher than that in the cytoplasm at the resting *** large Ca^(2+)level gradient across the membrane between the interior and exterior can cause Ca^(2+)overload and *** have evolved mechanisms to export Ca^(2+)out of the cytoplasm or store it in intracellular organelles,such as endoplasmic reticulum(ER),mitochondria,and ***,Ca^(2+)-binding proteins,including those containing the most common Ca^(2+)-binding EF-hand domains,maintain the cytosolic Ca^(2+)level by directly binding them,thus participating in Ca^(2+)***^(2+)/H+exchangers(CAXs,antiporter)and Ca^(2+)-ATPases(ACAs)are responsible for transferring Ca^(2+)from the cytosol to either the external space or intracellular stores(Bose et al.,2011).However,it is still unknown how these Ca^(2+)-scavenging transporters are activated when the cytosolic Ca^(2+)level is elevated to threshold ***“auto-regulatory”mechanism to scavenge excess cytosolic Ca^(2+),providing a guarding system to maintain cytosolic Ca^(2+)homeostasis in plants.

关键词： maintain mechanism immunity

维普期刊数据库

Harnessing the Streptomyces-originating type I-E CRISPR/Cas system for efficient genome editing in Streptomyces

在线全文

学校读者我要写书评

暂无评论

Science China Life Sciences 2025年

作者： Yuhui Xie Xiaoyan Liu Tingting Wu Yunzi Luo Frontiers Science center for synthetic biology and Key Laboratory of systems Bioengineering (Ministry of Education) School of Chemical Engineering and TechnologyTianjin University Department of Gastroenterology State Key Laboratory of BiotherapyWest China HospitalSichuan University Georgia Tech Shenzhen Institute Tianjin University Haihe Laboratory of Sustainable Chemical Transformations

Since their discovery,CRISPR/Cas systems have significantly expanded the genetic toolbox,aiding in the exploration and enhanced production of natural products across various *** these,class 2 CRISPR/Cas systems are simpler and more broadly used,but they frequently fail to function effectively in many Streptomyces *** this study,we present an engineered class 1 type I CRISPR/Cas system derived from Streptomyces avermitilis,which enables efficient gene editing in phylogenetically distant Streptomyces *** a plasmid interference assay,we identified the effective protospacer adjacent motif as 5′-AAN-3′.Utilizing this system,we achieved targeted chromosomal deletions ranging from 8 bp to 100 kb,with efficiencies exceeding 92%.We further utilized this system to insert DNA fragments into different Streptomyces genomes,facilitating the heterologous expression of exogenous genes and the activation of endogenous natural product biosynthetic gene ***,we established a type I CRISPR/Cas-based gene-editing methodology that significantly advances the exploration of Streptomyces,known for their rich natural product *** is the first report of a gene editing tool developed based on the endogenous class 1 type I CRISPR/Cas system in Streptomyces *** work enriches the Streptomyces gene manipulation toolbox and advances the discovery of valuable natural products within these organisms.

关键词：

Dual atom-bridge effect promoting interfacial charge transfer in 2D/2D Cs3Bi2Br9/BiOBr epitaxial heterojunction for efficient photocatalysis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2025年第2期36卷 218-223页

作者： Yuan Teng Zichun Zhou Jinghua Chen Siying Huang Hongyan Chen Daibin Kuang MOE Key Laboratory of Bioinorganic and synthetic Chemistry LIFM GBRCE for Functional Molecular Engineering School of Chemistry IGCME Sun Yat-sen University National Experimental Teaching Demonstration center for Chemistry College of Chemistry and Chemical Engineering Jishou University

Optimizing the interfacial quality of halide perovskites heterojunction to promote the photogenerated charge separation is of great significance in photocatalytic ***,the delicately regulation of interfacial structure and properties of halide perovskites hybrid is still a big challenge owing to the growth uncontrollability and incompatibility between different *** we use Bi OBr nanosheets as the start-template to in situ epitaxially grow Cs3Bi2Br9nanosheets by“cosharing”Bi and Br atoms strategy for designing a 2D/2D Cs3Bi2Br9/BiOBr *** studies show that the epitaxial heterojunction can optimize the synergistic effect of Bi OBr and Cs3Bi2Br9via the formation of tight-contact interfaces,strong interfacial electronic coupling and charge redistribution,which can not only drive the Z-scheme charge transfer mechanism to greatly promote the spatial separation of electronhole pairs,but also modulate the interfacial electronic structure to facilitate the adsorption and activation of toluene *** heterojunction exhibited 62.3 and 2.4-fold photoactivity improvement for toluene oxidation to benzaldehyde than parental Bi OBr and Cs3Bi2Br9,*** study not only proposed a novel dual atom-bridge protocol to engineer high-quality perovskite heterojunctions,but also uncovered the potential of heterojunction in promoting electron-hole separation as well as the application in photocatalytic organic synthesis.

关键词： Bismuth oxyhalide Bismuth-based perovskite Direct Z-scheme heterojunction Dual atom-bridge effect Photocatalytic C(sp3)-H bond activation

Response surface optimization of preparation parameters and evaluation of the antioxidant and antihypertensive activities of Spirulina protein hydrolysates

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2025年第1期43卷 196-209页

作者： Qishan SUO Zhenzhen DENG Yang YUE Jing WANG Ning WU Lihua GENG Quanbin ZHANG CAS and Shandong Province Key Laboratory of Experimental Marine biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine biology and Biotechnology Qingdao Marine Science and Technology CenterQingdao 266237China University of Chinese Academy of Sciences Beijing 101408China

Safety,high protein content,and the numerous health benefits make Spirulina an outstanding source of bioactive *** from Spirulina,which exhibit antioxidant,anti-inflammatory,and antihypertensive effects,may assist in the management of cardiovascular diseases(CVDs).Here,we present the optimization of enzyme-digested hydrolysates derived from Spirulina *** using response surface methodology(RSM).We also evaluated the biological activity of Spirulina protein hydrolysates(SPHs)in contributing to the amelioration of hypertension and associated cardiovascular *** findings suggest that Spirulina protein extracts contain a complex proteinaceous composition with phycocyanin being the dominant protein,as evidenced by both SDS-PAGE and LC-MS/MS *** protease,protease K,andα-chymotrypsin exhibited a substantial hydrolytic effect on Spirulina protein,taking into account their degree of hydrolysis(DH),peptide yield,and molecular weight ***-factor experiments identified pH,temperature,and enzyme/substrate ratio as the key factors influencing ***,optimal hydrolysis conditions for the proteases were determined via RSM,leading to a considerable enhancement of the actual *** showed that SPHs have strong antioxidant activity against various free radicals,with a higher ability to scavenge hydroxyl ***,SPHs inhibited macrophage nitric oxide secretion and significantly inhibited angiotensin I-converting enzyme in vitro at 400μg/*** is worth noting that SPHs prepared with protease K exhibited a potent anti-hypertensive effect in *** findings indicate the potential usefulness of including dietary SPHs in preventing hypertension and associated *** research could be valuable in guiding the development of health-promoting foods within the Spirulina industry.

关键词： antioxidant activity antihypertensive effect angiotensin converting enzyme inhibition response surface methodology Spirulina

维普期刊数据库

An Online Exploratory Maximum Likelihood Estimation Approach to Adaptive Kalman Filtering

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 228-254页

作者： Jiajun Cheng Haonan Chen Zhirui Xue Yulong Huang Yonggang Zhang the College of Intelligent systems Science and Engineering Harbin Engineering University the Engineering Research center of Navigation Instruments Ministry of Education the College of Intelligent systems Science and Engineering the College of Future Technology Harbin Engineering University IEEE

Over the past few decades, numerous adaptive Kalman filters(AKFs) have been proposed. However, achieving online estimation with both high estimation accuracy and fast convergence speed is challenging, especially when both the process noise and measurement noise covariance matrices are relatively inaccurate. Maximum likelihood estimation(MLE) possesses the potential to achieve this goal, since its theoretical accuracy is guaranteed by asymptotic optimality and the convergence speed is fast due to weak dependence on accurate state ***, the maximum likelihood cost function is so intricate that the existing MLE methods can only simply ignore all historical measurement information to achieve online estimation,which cannot adequately realize the potential of MLE. In order to design online MLE-based AKFs with high estimation accuracy and fast convergence speed, an online exploratory MLE approach is proposed, based on which a mini-batch coordinate descent noise covariance matrix estimation framework is developed. In this framework, the maximum likelihood cost function is simplified for online estimation with fewer and simpler terms which are selected in a mini-batch and calculated with a backtracking method. This maximum likelihood cost function is sidestepped and solved by exploring possible estimated noise covariance matrices adaptively while the historical measurement information is adequately utilized. Furthermore, four specific algorithms are derived under this framework to meet different practical requirements in terms of convergence speed, estimation accuracy,and calculation load. Abundant simulations and experiments are carried out to verify the validity and superiority of the proposed algorithms as compared with existing state-of-the-art AKFs.

关键词： Adaptive Kalman filtering coordinate descent maximum likelihood estimation mini-batch optimization unknown noise covariance matrix

Power synchronization: taming massive diversified serverless functions under power constraints

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年第03期68卷 47-65页

作者： Du LIU Lu ZHANG Yechen XU Xinkai WANG Lingyu SUN Yifei PU Xiaofeng HOU Chao LI Minyi GUO Department of Computer Science and Engineering Shanghai Jiao Tong University AI Chip center for Emerging Smart systems The Hong Kong University of Science and Technology

Carbon neutrality has become an important design objective worldwide. However, the on-going shift to cloud-naive era does not necessarily mean energy efficiency. From the perspective of power management, co-hosted serverless functions are difficult to tame. They are lightweight, short-lived applications sensitive to power capping activities. In addition, they exhibit great individual and temporal variability, presenting idiosyncratic performance/power scaling goals that are often at odds with one another. To date, very few proposals exist in terms of tailored power management for serverless platforms. In this work, we introduce power synchronization, a novel yet generic mechanism for managing serverless functions in a power-efficient way. Our insight with power synchronization is that uniform application power behavior enables consistent and uncompromised function operation on shared host machines. We also propose PowerSync, a synchronization-based power management framework that ensures optimal efficiency based on a clear understanding of functions. Our evaluation shows that PowerSync can improve the energy efficiency of functions by up to 16% without performance loss compared to conventional power management strategies.

关键词： serverless computing variability energy efficiency power management power synchronization

Solar refinery: a disruptive strategy for upcycling plastic wastes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Baowen Zhou Ding Wang Key Laboratory for Power Machinery and Engineering of Ministry of Education Research Center for Renewable Synthetic Fuel School of Mechanic Engineering Shanghai Jiao Tong University

Waste or treasure. Plastics, derived from fossil fuels, have revolutionized modern life by providing convenience and benefits across various industries, including packaging,housing, biomedicine, and automotive. Since their commercialization in the 1930s and 1940s [1], over 7 billion tons of plastics have been produced, with an annual output exceeding 380 million tons [2].

关键词：