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Chinese Journal of Aeronautics 2024年第5期37卷 570-585页

作者： Biao QIN Henan LIU Jian CHENG Jinchuan TIAN Jiangang SUN Zihan ZHOU Chuanzhen MA Mingjun CHEN State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001China

As for the ultra-precision grinding of the hemispherical fused silica resonator,due to the hard and brittle nature of fused silica,subsurface damage(SSD)is easily generated,which enormously influences the performance of such ***,ultra-precision grinding experiments are carried out to investigate the surface/subsurface quality of the hemispherical resonator machined by the small ball-end fine diamond grinding *** influence of grinding parameters on the surface roughness(SR)and SSD depth of fused silica samples is then *** experimental results indicate that the SR and SSD depth decreased with the increase of grinding speed and the decrease of feed rate and grinding *** addition,based on the material strain rate and the maximum undeformed chip thickness,the effect of grinding parameters on the subsurface damage mechanism of fused silica samples is ***,a multi-step ultra-precision grinding technique of the hemispherical resonator is proposed based on the interaction influence between grinding depth and feed ***,the hemispherical resonator is processed by the proposed grinding technique,and the SR is improved from 454.328 nm to 110.449 nm while the SSD depth is reduced by 94%from 40μm to 2.379μ*** multi-step grinding technique proposed in this paper can guide the fabrication of the hemispherical resonator.

关键词： Fused silica Ultra-precision grinding Hemispherical resonator Subsurface damage Grinding technique

Lactate regulates major zygotic genome activation by H3K18 lactylation in mammals

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National science Review 2024年第2期11卷 124-134页

作者： Jingyu Li Weibo Hou Qi Zhao Wei Han Hongdi Cui Songling Xiao Ling Zhu Jiadan Qu Xiaoyu Liu Weitao Cong Jingling Shen Yuzheng Zhao Shaorong Gao Guoning Huang Qingran Kong Chongqing Key Laboratory of Human Embryo Engineering Center for Reproductive Medicine Chongqing Health Center for Women and ChildrenWomen and Children's Hospital of Chongqing Medical University Oujiang Laboratory Zhejiang Provincial Key Laboratory of Medical Genetics Key Laboratory of Laboratory MedicineMinistry of EducationSchool of Laboratory Medicine and Life Sciences Wenzhou Medical University Frontier science Center for Stem Cell Research School of Life Sciences and Technology Tongji University School of Pharmaceutical science Wenzhou Medical University institute of Life sciences College of Life and Environmental Sciences Wenzhou University Optogenetics&Synthetic Biology Interdisciplinary Research Center State Key Laboratory of Bioreactor Engineering Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism School of Pharmacy East China University of Science and Technology

Lactate is present at a high level in the microenvironment of mammalian preimplantation embryos in vivo and in vitro. However, its role in preimplantation development is unclear. Here, we report that lactate is highly enriched in the nuclei of early embryos when major zygotic genome activation(ZGA) occurs in humans and mice. The inhibition of its production and uptake results in developmental arrest at the 2-cell stage, major ZGA failure, and loss of lactate-derived H3K18lac, which could be rescued by the addition of Lac-Co A and recapitulated by overexpression of H3K18R mutation. By profiling the landscape of H3K18lac during mouse preimplantation development, we show that H3K18lac is enriched on the promoter regions of most major ZGA genes and correlates with their expressions. In humans, H3K18lac is also enriched in ZGA markers and temporally concomitant with their expressions. Taken together, we profile the landscapes of H3K18lac in mouse and human preimplantation embryos, and demonstrate the important role for H3K18lac in major ZGA, showing that a conserved metabolic mechanism underlies preimplantation development of mammalian embryos.

关键词： mammalian preimplantation development lactate epigenetic remodeling histone lactylation zygotic genome activation

Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole Cycles

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Chinese Journal of Polymer science 2024年第4期42卷 437-445页

作者： Natalya V.Zakharova Stanislav N.Zelinskiy Mariya S.Strelova Elena N.Danilovtseva Vadim V.Annenkov institute of Macromolecular Compounds of the Russian Academy of sciences Saint Petersburg199004Russia Limnological institute of Siberian Branch of the Russian Academy of sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization

Post-synthetic modifications of MOFs by different bolt ligands for controllable release of cargoes

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Chinese Chemical Letters 2024年第10期35卷 404-407页

作者： Hao Wang Meng-Qi Pan Ya-Fei Wang Chao Chen Jian Xu Yuan-Yuan Gao Chuan-Song Qi Wei Li Xian-He Bu College of New Materials and Chemical Engineering Beijing Key Lab of Special Elastomeric Composite MaterialsBeijing Institute of Petrochemical TechnologyBeijing 102617China School of Materials science and Engineering National Institute for Advanced MaterialsTKL of Metal and Molecule-Based Material ChemistryNankai UniversityTianjin300350China College of Chemical Engineering Inner Mongolia University of TechnologyHohhot 010051China

Post-synthetic modifications(PSM)have drawn great attention as a vigoroso tool to tune or enhance the performance of metal-organic frameworks(MOFs).However,the current PSM method usually have to sacrifice the porosity of MOFs to enrich their functionality,such as pore space partition(PSP)and postsynthetic elimination and insertion(PSE&I),causing a trade-off in this *** address this issue,we herein propose a new PSM strategy of using the size-matching ligands as the bolts to lock MOFs'pores,which could be anchored onto open metal sites(OMSs)after guest loading through a stepwise *** a result,the loaded cargoes undergo a controlled releasing process with respect to different bolt *** proposed strategy provides a promising way to balance the functionality and porosity of MOFs.

关键词： Post-synthetic modifications Metal-organic frameworks Bolting ligand Control release Cargo

Application of Predictive Model for Efficient Cassava (Manihot esculenta Crantz) Yield in the Face of Climate Variability in Enugu State, Nigeria

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American Journal of Climate Change 2024年第2期13卷 361-389页

作者： Emeka Bright Ogbuene Tonia Nkiru Nwobodo Obianuju Gertrude Aloh Achoru Fred Emeka Josiah C. Ogbuka Vivian Amarachi Ozorme Andrew M. Oroke Obiageli Jacinta Okolo Anwara Obianuju Amara E. S. Enemuo Centre for Environmental Management and Control (CEMAC) University of Nigeria Nsukka Nigeria Department of Geography University of Nigeria Nsukka Nigeria Department of Geography and meteorology Enugu State University of Science and Technology (ESUT) Enugu Nigeria School of Civil Engineering Newcastle University Newcastle upon Tyne UK

Climate variability as occasioned by conditions such as extreme rainfall and temperature, rainfall cessation, and irregular temperatures has considerable impact on crop yield and food security. This study develops a predictive model for cassava yield (Manihot esculenta Crantz) amidst climate variability in rainfed zone of Enugu State, Nigeria. This study utilized data of climate variables and tonnage of cassava yield spanning from 1971 to 2012;as well as information from a questionnaire and focus group discussion from farmers across two seasons in 2023 respectively. Regression analysis was employed to develop the predictive model equation for seasonal climate variability and cassava yield. The rainfall and temperature anomalies, decadal change in trend of cassava yield and opinion of farmers on changes in rainfall season were also computed in the study. The result shows the following relationship between cassava and all the climatic variables: R2 = 0.939;P = 0.00514;Cassava and key climatic variables: R2 = 0.560;P = 0.007. The result implies that seasonal rainfall, temperature, relative humidity, sunshine hours and radiation parameters are key climatic variables in cassava production. This is supported by computed rainfall and temperature anomalies which range from −478.5 to 517.8 mm as well as −1.2˚C to 2.3˚C over the years. The questionnaire and focus group identified that farmers experienced at one time or another, late onset of rain, early onset of rain or rainfall cessation over the years. The farmers are not particularly sure of rainfall and temperature characteristics at any point in time. The implication of the result of this study is that rainfall and temperature parameters determine the farming season and quantity of productivity. Hence, there is urgent need to address the situation through effective and quality weather forecasting network which will help stem food insecurity in the study area and Nigeria at large. The study made recommendations such as a

关键词： Climate Variability Cassava (Manihot esculenta Crantz) Predictive Model Yield

Allogenic microglia replacement:A novel therapeutic strategy for neurological disorders

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Fundamental Research 2024年第2期4卷 237-245页

作者： Yanxia Rao Bo Peng Department of Laboratory Animal science MOE Frontiers Center for Brain ScienceFudan UniversityShanghai 200032China Department of Neurosurgery Huashan HospitalInstitute for Translational Brain ResearchState Key Laboratory of Medical NeurobiologyMOE Frontiers Center for Brain ScienceMOE Innovative Center for New Drug Development of Immune Inflammatory DiseasesFudan UniversityShanghai 200000China Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu 226001China

Microglia are resident immune cells in the central nervous system(CNS)that play vital roles in CNS development,homeostasis and disease *** defects in microglia lead to microglial dysfunction,which in turn leads to neurological *** correction of the specific genetic defects in microglia in these disorders can lead to therapeutic *** genetic defect correction approaches are dependent on viral vectorbased genetic defect ***,the viruses used in these approaches,including adeno-associated viruses,lentiviruses and retroviruses,do not primarily target microglia;therefore,viral vector-based genetic defect corrections are ineffective in *** replacement is a novel approach to correct microglial genetic defects via replacing microglia of genetic defects with allogenic healthy *** this paper,we systematically review the history,rationale and therapeutic perspectives of microglia replacement,which would be a novel strategy for treating CNS disorders.

关键词： Microglia Replacement Microglia replacement Microglia depletion Microglia-free niche CSF1R

A New Method for Calculating the Wind Speed Distribution of a Moving Tropical Cyclone

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Advances in Atmospheric sciences 2010年第1期27卷 69-79页

作者：胡邦辉杨修群谭言科王咏青范勇 institute of Severe Weather and Climate Nanjing University institute of meteorology PLA University of Science and Technology Nanjing University of Information science and Technology

Based on gradient wind equations, including frictional force, and considering the effect of the movement of a tropical cyclone on wind speed, the Fujita Formula is improved and further simplified, and the numerical scheme for calculating the maximum wind speed radius and wind velocity distribution of a moving tropical cyclone is derived. In addition, the effect of frictional force on the internal structure of the tropical cyclone is discussed. By comparison with observational data, this numerical scheme demonstrates great advantages, i.e. it can not only describe the asymmetrical wind speed distribution of a tropical cyclone reasonably, but can also calculate the maximum wind speed in each direction within the typhoon domain much more accurately. Furthermore, the combination of calculated and analyzed wind speed distributions by the scheme is perfectly consistent with observations.

关键词： tropical cyclone maximum wind speed radius wind velocity distribution

CHARACTERISTICS OF MEI-YU PRECIPITATION AND SVD ANALYSIS OF PRECIPITATION OVER THE YANGTZE-HUAIHE RIVERS VALLEYS AND THE SEA SURFACE TEMPERATURE IN THE NORTHERN PACIFIC OCEAN

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Journal of Tropical meteorology 2008年第2期14卷 129-132页

作者：毛文书王谦谦彭骏李永华 institute of Atmospheric science NUIST Center of Plateau Atmospheric and Environmental Research Chengdu University of Information Technology Chengdu institute of Plateau meteorology CMA Chongqing institute of meteorology science

Based on the precipitation data of Meiyu at 37 stations in the valleys of Yangtze and Huaihe Rivers from 1954 to 2001, the temporal-spatial characteristics of Meiyu precipitation and their relationships with the sea surface temperature in northern Pacific are investigated using such methods as harmonic analysis, empirical orthogonal ftmction （EOF）, composite analysis and singular value decomposition （SVD）. The results show that the temporal evolution and spatial distribution of Meiyu precipitation are not homogeneous in the Yangtze-Huaihe Rivers basins but with prominent inter-annual and inter-decadal variabilities. The key region between the anomalies of Meiyu precipitation and the monthly sea surface temperature anomalies （SSTA） lies in the west wind drift of North Pacific, which influences the precipitation anomaly of Meiyu precipitation over a key period of time from January to March in the same year. When the SST in the North Pacific west wind drift is warmer （colder） than average during these months, Meiyu precipitation anomalously increases （decreases） in the concurrent year. Results of SVD are consistent with those of composite analysis which pass the significance test of Monte-Carlo at 0.05.

关键词： Meiyu harmonic analysis EOF SVD Monte-Carlo test Sea Surface Temperature (SST) of North Pacific Ocean

Ultrabright near-infrared light

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Light(science & Applications) 2024年第4期13卷 609-609页

作者： Andries Meijerink Debye institute for Nanomaterials science Utrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands

Nature Photonics(2024)https://***/10.1038/s41566-024-01400-7 The recent race for bright and broadband near-infrared(NIR)light sources has focused on new luminescent materials(phosphors)for efficient conversion of blue light emitting diode(LED)emission to broadband *** extreme brightness,blue laser diodes(LDs)are superior to LEDs as they maintain efficiency at high current ***,so far NIR phosphors suffered from severe efficiency droop at these high pumping *** team of Zhiguo Xia from South China University of Technology reported a record high 6 Watt NIR output from LDpumped MgO:Cr^(3+)translucent ceramics emitting around 810 ***,MgO:Cr^(3+)is an old phosphor,extensively studied in the past *** success is based in spark plasma sintering of translucent MgO:Cr^(3+)ceramics using nanosilica as flux,incorporated at grain *** refractive index contrast between MgO and SiO2 induces scattering of blue light,increasing light absorption,and the dense ceramic has excellent thermal conductivity,reducing thermal quenching of NIR *** new scheme using NIR-emitting translucent ceramics for laser-driven NIR light sources will propel photonics applications in night vision,biomedical imaging and sensing.

关键词： ceramics ceramic maintain

A Study of the Effect of Topography on the Merging of Vortices

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Advances in Atmospheric sciences 2004年第1期21卷 13-22页

作者：陈联寿罗哲贤 Chinese Academy of Meteorological science Beijing 100081 Nanjing institute of meteorology Nanjing 210044

Eight sets of numerical experiments are performed in 48 hours of integtation by using a barotropic primitive equation model with a topographic term so as to investigate the effect of topography on the merging of vortices. It is pointed out that the introduction of topography may change the track of vortices, and it causes the low vortices and vorticity lumps to be detained on the southeast side of the topography, thus creating a favorable condition for the merging of the low vortex and vorticity lumps. It is also shown that the effect of topography may cause double mergers of vortices in a horizontally shearing basic flow, and it can strengthen the low vortex remarkably.

关键词： topography vortex vortices merger