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Continuous-flow synthesis of polysubstituted γ-butyrolactones via enzymatic cascade catalysis

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Chinese Chemical Letters 2024年第4期35卷 404-408页

作者： Liliang Chu Xiaoyan Zhang Jianing Li Xuelei Deng Miao Wu Ya Cheng Weiping Zhu Xuhong Qian Yunpeng Bai State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Center for BiomanufacturingEast China University of Science and TechnologyShanghai 200237China The Extreme Optoelectromechanics Laboratory School of Physics and Materials ScienceEast China Normal UniversityShanghai 200241China

Polysubstituted chiral γ-butyrolactones are the core structural units of many natural products and high value-added flavors and fragrances used in the food and cosmetic industry. Current enzymatic cascade synthesis of these molecules faces the problems of low enzyme activity and phase separation in batch reaction, resulting in low productivity. Herein, we report a new continuous-flow process to synthesize the optically pure Nicotiana tabacum lactone(3S,4S)-4a and whisky lactone(3R,4S)-4b from α,β-unsaturatedγ-ketoesters. A new ene reductase(ER) from Swingsia samuiensi(Ss ER) and a carbonyl reductase(Ss CR)were engineered by directed evolution to improve their activity and thermostability. The continuous-flow preparative reactions were performed in two 3D microfluidic reactors, generating(3S,4S)-4a(99% ee and87% de) and(3R,4S)-4b(99% ee and 98% de) with space-time yields 3 and 7.4 times higher than those of the batch reactions. The significant enhancement in the productivity of enzyme cascade catalysis brought by cutting-edge continuous microfluidic technology will benefit the general multi-enzyme catalytic systems in the future.

关键词： Enzyme catalysis Cascade catalysis Directed evolution Continuous-flow γ-Butyrolactones

Construction and characterization of a humanized SLCO1B1 rat model with its application in evaluating the uptake of different statins

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1592-1604页

作者： Yuanjin Zhang Junze Huang Shengbo Huang Jie Liu Luyao Deng Chenmeizi Liang Yuanqing Guo Bingyi Yao Xin Wang Changning Maternity and Infant Health Hospital and School of Life Sciences Shanghai Key Laboratory of Regulatory BiologyEast China Normal UniversityShanghai 200241China

Organic anion-transporting polypeptides IB1(OATPIB1)plays a crucial role in the transport of ***,there are too few animal models related to OATPIB1,especially humanized animal *** this study,the human SLCOIB1 cDNA was inserted into the second exon of the rat Slcolb2 gene using CRISPR/Cas9 *** characteristics of statins were conducted in wild-type(WT),humanized OATPIB1(hOATPIB1),and OATPIB2 knockout(OATPIB2 KO)rats,*** results showed that human OATPIB1 was successfully expressed in rat liver and exhibited transport ***,the pharmacokinetic results revealed that OATPIB1 exhibited varying uptake levels of pivastatin,rosuvastatin,and fluvastatin,leading to different levels of exposure within the *** results were consistent with those obtained from in vitro experiments using overexpressed cell *** conclusion,we established a novel humanized SLCOIBI transgenic rat model to assess the role of human OATPIB1 in the uptake of different *** different uptake mediated by OATPIB1 may be an important reason for the different efficacy of *** hOATPIB1 rat is a promising model for improving the prediction of human drug transport.

关键词： CRISPR/Cas9 Drug transport Drug disposition Geneediting Humanized rat model OATP1B1 SLCO1B1 Statins

Promoting Environmental Risk Assessment and Control of Emerging Contaminants in china

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Engineering 2024年第6期37卷 13-17页

作者： Bin Wang Qian Sui Huijuan Liu Gang Yu Jiuhui Qu School of Environment Tsinghua UniversityBeijing 100084China School of Resources and Environmental Engineering East China University of Science and TechnologyShanghai 200237China Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal UniversityZhuhai 519000China

*** In recent years,china has carried out an extensive preventative battle against air,water,and soil pollution,and the nation’s environmental quality-as reflected by conventional pollutant indicators—has significantly *** the same time,the issue of emerging contaminants(ECs)is beginning to receive increasing *** generally refer to newly discovered or noticeable pollutants that pose risks to the ecological environment or human *** they have not been included in environmental management,or existing management measures are insufficient to effectively prevent and control their *** ECs of greatest concern generally include persistent organic pollutants(POPs),endocrine-disrupting chemicals(EDCs),pharmaceuticals and personal care products(PPCPs),and *** four categories of ECs are not entirely separate,as they interrelate with each other(Fig.1).Chemical production and product usage are the main sources of *** is the world’s largest producer and consumer of bulk chemicals,and the production value of china’s chemical industry is predicted to reach 50%of the global total by 2030[1].Scientific control of ECs based on their environmental risk assessment is a necessary way to support the prevention and legal governance of ECs.

关键词： legal entirely prevention

Centroid Hom-associative Algebras and Centroid Hom-Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第4期40卷 935-961页

作者： Yu Xiu BAI Leonid A.BOKUT Yu Qun CHEN Ze Rui ZHANG department of mathematics Teaching Guangzhou Civil Aviation CollegeGuangzhou 510403P.R.China Sobolev Institute of mathematics Novosibirsk 630090Russia Novosibirsk State university Novosibirsk 630090Russia School of Mathematical Sciences South China Normal UniversityGuangzhou 510631P.R.China

In this article,we construct free centroid hom-associative algebras and free centroid hom-Lie *** also construct some other relatively free centroid hom-associative algebras by applying the Gr?bner-Shirshov basis theory for(unital)centroid hom-associative ***,we prove that the"Poincaré-Birkhoff-Witt theorem"holds for certain type of centroid hom-Lie algebras over a field of characteristic 0,namely,every centroid hom-Lie algebra such that the eigenvectors of the mapβlinearly generates the whole algebra can be embedded into its universal enveloping centroid hom-associative algebra,and the linear basis of the universal enveloping algebra does not depend on the multiplication table of the centroid hom-Lie algebra under consideration.

关键词： Centroid hom-Lie algebra centroid hom-associative algebra Gr?bner-Shirshov basis

Dynamic analysis of a latent HIV infection model with CTL immune and antibody responses

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International Journal of Biomathematics 2024年第3期17卷 289-316页

作者： Zhiqi Zhang Yuming Chen Xia Wang Libin Rong School of mathematics and Statistics Xinyang normal university XinyangHenan 464000P.R.China department of mathematics Wilfrid Laurier university WaterlooONN2L 3C5Canada department of mathematics university of Florida GainesvilleFL 32611USA

This paper develops a mathematical model to investigate the Human Immunodeficiency Virus(HIV)infection *** model includes two transmission modes(cell-to-cell and cell-free),two adaptive immune responses(cytotoxic T-lymphocyte(CTL)and antibody),a saturated CTL immune response,and latent HIV *** existence and local stability of equilibria are fully characterized by four reproduction *** sensitivity analyses,we assess the partial rank correlation coefficients of these reproduction numbers and identify that the infection rate via cell-to-cell transmission,the number of new viruses produced by each infected cell during its life cycle,the clearance rate of free virions,and immune parameters have the greatest impact on the reproduction ***,we compare the effects of immune stimulation and cell-to-cell spread on the model's *** findings highlight the significance of adaptive immune responses in increasing the population of uninfected cells and reducing the numbers of latent cells,infected cells,and ***,cell-to-cell transmission is identified as a facilitator of HIV *** analytical and numerical results presented in this study contribute to a better understanding of HIV dynamics and can potentially aid in improving HIV management strategies.

关键词： HIV infection cell-to-cell transmission adaptive immune response latent infection local stability

Remodeling the immune microenvironment for gastric cancer therapy through antagonism of prostaglandin E2 receptor 4

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Genes & Diseases 2024年第4期11卷 411-425页

作者： Mengmeng Guo Pan Hu Jiayi Xie Kefu Tang Shixiu Hu Jialiang Sun Yundong He Jing Li Weiqiang Lu Huirong Liu Mingyao Liu Zhengfang Yi Shihong Peng Shanghai Key Laboratory of Regulatory Biology School of Life SciencesEast China Normal UniversityShanghai 200241China Prenatal Diagnosis Center Department of Clinical LaboratoryChangning Maternity and Infant Health HospitalEast China Normal UniversityShanghai 200051China Key Laboratory of Acupuncture and Immunological Effects Shanghai University of Traditional Chinese MedicineShanghai 201203China Fengxian Hospital Affiliated to Southern Medical university Shanghai 201400China Shanghai Yuyao Biotech Co. Ltd.Shanghai 200241China

Gastric cancer is highly prevalent among digestive tract *** to the intri-cate nature of the gastric cancer immune microenvironment,there is currently no effective treatment available for advanced gastric ***,there is promising potential for immunotherapy targeting the prostaglandin E2 receptor subtype 4(EP4)in gastric *** our previous study,we identified a novel small molecule EP4 receptor antagonist called *** with YY001 alone demonstrated a significant reduction in gastric cancer growth and inhibited tumor metastasis to the lungs in a mouse ***,adminis-tration of YYo01 stimulated a robust immune response within the tumor microenvironment,characterized by increased infiltration of antigen-presenting cells,T cells,and M1 ***,our research revealed that YYo01 exhibited remarkable synergistic ef-fects when combined with the PD-1 antibody and the clinically targeted drug apatinib,rather than *** findings suggest that YYo01 holds great promise as a potential therapeutic strategy for gastric cancer,whether used as a standalone treatment or in combination with other drugs.

关键词： EP4 Immunomodulation Synergy Tumor microenvironment YY001

Intrinsically asymmetric atomic character regulates piezoelectricity in two-dimensional materials

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Frontiers of physics 2024年第3期19卷 153-162页

作者： Yun-Qin Li Qi-Wen He Dai-Song Tang Xiao Shang Xiao-Chun Wang School of Physics Science and Information Technology Liaocheng UniversityLiaocheng 252000China Key Laboratory of Polar Materials and Devices Ministry of EducationDepartment of ElectronicsEast China Normal UniversityShanghai 200241China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

Decreasing of layer thickness causes the decrease of polarization until it disappears due to the existence of depolarization ***,the search for strong piezoelectric materials is highly desirable for multifunctional ultra-thin piezoelectric ***,we propose a common strategy for achieving strong piezoelectric materials through the electronic asymmetry induced by the intrinsically asymmetric atomic character of different chalcogen ***,in the tetrahedral lattice structures,for example,M4X3Y3(M=Pd/Ni,X/Y=S,Se or Te,X≠Y)monolayers are proved to display excellent out-of-plane ***4Se3Te3 possesses the largest piezoelectric coefficient d33 of 61.57 pm/V,which is much larger than that of most 2D *** the electronic asymmetry further increases the out-of-plane piezoelectricity of Janus M4X3Y3 ***,the out-of-plane piezoelectricity is positively correlated with the ratio of electronegativity difference(Red)and the electric dipole moment(P).This work provides alternative materials for energy harvesting nano-devices or self-energized wearable devices,and supplies a valuable guideline for predicting 2D materials with strong out-of-plane piezoelectricity.

关键词： piezoelectricity intrinsically asymmetric atomic character ratio of electronegativity difference electric dipole moment first-principles calculations

Enhancing SAEAs with unevaluated solutions:a case study of relation model for expensive optimization

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Science china(Information Sciences) 2024年第2期67卷 41-58页

作者： Hao HAO Xiaoqun ZHANG Aimin ZHOU Institute of Natural Sciences Shanghai Jiao Tong University Shanghai Frontiers Science Center of Molecule Intelligent Syntheses School of Computer Science and Technology East China Normal University

Surrogate-assisted evolutionary algorithms(SAEAs) hold significant importance in resolving expensive optimization problems. Extensive efforts have been devoted to improving the efficiency of SAEAs through the development of proficient model-assisted solution selection methods, which, however, first requires generating high-quality solutions. The fundamental paradigm of evaluating a limited number of solutions in each generation within SAEAs reduces the variance of adjacent populations, thereby affecting the quality of offspring solutions. This is a frequently encountered issue yet receives little attention. To address the issue, this paper presents a framework using unevaluated solutions to enhance the efficiency of *** surrogate model is employed to identify high-quality solutions for the direct generation of new solutions without evaluation. To ensure dependable selection, we have introduced two tailored relation models to select the optimal solution and the unevaluated population. A comprehensive experimental analysis is performed on two test suites, which showcases the superiority of the relation model over regression and classification models in the solution selection phase. Furthermore, the surrogate-selected unevaluated solutions with high potential have been shown to enhance the efficiency of the algorithm significantly.

关键词： expensive optimization unevaluated solutions relation model surrogate-assisted evolutionary algorithm

Quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms

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Journal of Mountain Science 2024年第1期21卷 322-334页

作者： QIN Yanhui MA Haoyuan ZHANG Lele YIN Jinshuai ZHENG Xionghui LI Shuo department of Civil Engineering Qingdao University of TechnologyQingdao 266520China department of Geography Qinghai Normal UniversityXining 810008China

The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP.

关键词： Freeze–thaw cycles Quantification Machine learning algorithms Qinghai–Tibet Plateau Concrete