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Permeation of dimethyl sulfoxide into articular cartilage at subzero temperatures

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第3期13卷 213-220页

作者： Shao-zhi ZHANG xiao-yi yu guang-ming CHEN Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Osteochondral allografting has been proved to be a useful method to treat diseased or damaged areas of joint surfaces. Operational long-term stocks of grafts which supply a buffer between procurement and utilization would contribute to the commercialization or industrialization of this technology. Vitrification has been thought to be a promising method for successful preservation of articular cartilage （AC）, but high concentration cryoprotectants （CPAs） are used which may cause high cellular toxicity. An effective way to reduce CPA toxioity is to increase CPA concen- tration gradually while the temperature is lowered. Understanding the mechanism of （31~A permeation at subzero temperatures is important for designing the cryopreservation protocol. In this research, the permeation of dimethyl sulfoxide （MezSO） in ovine AC at subzero temperatures was studied experimentally. Pretreated AC discs were ex- posed in Me2SO solutions for different time （0, 5, 15, 30, 50, 80, and 120 min） at three temperature levels （-10, -20, and -30℃）. The Me2SO concentration within the tissue was determined by ultraviolet （UV） spectrophotometry. The diffusion coefficients were estimated to be 0.85×10-6, 0.48×10-8, and 0.27×10-6 cm2/s at -10, -20, and -,30℃, respectively, and the corresponding activation energy was 29.23 kJ/mol. Numerical simulation was performed to com- pare two Me2SO addition protocols, and the results demonstrated that the total loading duration could be effectively reduced with the knowledge of permeation kinetics.

关键词： Articular cartilage Vitrification Dimethyl sulfoxide Permeation Diffusion coefficient Subzero temperature

Influence of Integral Instability of Kramers-Kronig Transformation on Photoabsorption Cross Sections

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Communications in Theoretical Physics 2009年第8期52卷 369-376页

作者： MA xiao-guang GONG yu-Bing QU Zhao-Jun Department of Physics Ludong University Yantai 264025 China

The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent not only on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomie interactions in condensed environment. The real parts of the polarizabilities calculated usually by using the famous Kramers-Kronig transformation （KKT） from the photoabsorption cross sections of the isolated atoms are very sensitive to the accuracy of the implementation method of the infinite integral in the KKT. The influence of the integral instability of the KKT and the real part of the polarizability on the variation of the photoabsorption cross sections with the number density and the structure of the condensed matter has been studied in the present work for the first time. The conclusion is that the integration method with interpolation has given more reasonable results than the direct truncation method if some appropriate interpolation functions have been used. Some notes and conclusions have also been given for the applications of the alternative coupled expressions of photoabsorption cross sections.

关键词： condensed-phase photoabsorption Kramers-Kronig transformation dynamic polarizability

Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： Ying Qin Kai-Fan Ji Hui Liu xiao-guang yu yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set,1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test *** data preprocessing,we randomly cropped 128×128 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512×512 sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

A large-scale gene discovery for the red palm weevil Rhynchophorus ferrugineus （Coleoptera： Curculionidae）

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Insect Science 2013年第6期20卷 689-702页

作者： Lei Wang xiao-Wei Zhang Lin-Lin Pan Wan-Fei Liu Da-Peng Wang guang-yu Zhang yu-Xin Yin An Yin Shan-Gang Jia xiao-guang yu Gao-yuan Sun Song-Nian Hu Ibrahim S. AI-Mssallem Jun yu Joint Center for Genomics Research (JCGR) King Abdulaziz City for Science and Technology (KACST) and Chinese Academy of Sciences (CAS) Riyadh Kingdom of Saudi Arabia CAS Key Laboratory of Genome Sciences and Information Beijing Institute of Genomics Chinese Academy of Sciences Beijing Graduate University of Chinese Academy of Sciences Beijing China Department of Biotechnology College of Agriculture and Food Sciences King Faisal University AI-Hssa Hofuf Kingdom of Saudi Arabia

The red palm weevil （RPW; Rhynchophorusferrugineus） is a devastating pest of palms, prevalent in the Middle East as well as many other regions of the world. Here, we report a large-scale de novo complementary DNA （cDNA） sequencing effort that acquired ~5 million reads and assembled them into 26 765 contigs from 12 libraries made from samples of different RPW developmental stages based on the Roche/454 GS FLX platform. We annotated these contigs based on the publically available known insect genes and the Tribolium castaneum genome assembly. We find that over 80% of coding sequences （CDS） from the RPW contigs have high-identity homologs to known proteins with complete CDS. Gene expression analysis shows that the pupa and larval stages have the highest and lowest expression levels, respectively. In addition, we also identified more than 60 000 single nucleotide polymorphisms and 1 200 simple sequence repeat markers. This study provides the first large-scale eDNA dataset for RPW, a much-needed resource for future molecular studies.

关键词： full-length cDNA gene expression GS FLX Titanium pest red palm weevil

An Exposure Meter of Lijiang Fiber-fed High-Resolution Spectrograph

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Research in Astronomy and Astrophysics 2023年第11期23卷 60-66页

作者： xiao-guang yu Kai-Fan Ji Xi-Liang Zhang Liang Chang yun-Fang Cai Ying Qin Zhen-Hong Shang yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China

In 2016,an exposure meter was installed on the Lijiang Fiber-fed High-Resolution Spectrograph to monitor the coupling of starlight to the science fiber during *** on it,we investigated a method to estimate the exposure flux of the CCD in real time by using the counts of the photomultiplier tubes(PMT)of the exposure meter,and developed a piece of software to optimize the control of the exposure ***,by using flat-field lamp observations,we determined that there is a linear and proportional relationship between the total counts of the PMT and the exposure flux of the ***,using historical observations of different spectral types,the corresponding relational conversion factors were determined and obtained ***,the method was validated using actual observation data,which showed that all values of the coefficient of determination were greater than ***,software was developed to display the counts of the PMT and the estimated exposure flux of the CCD in real-time during the observation,providing a visual reference for optimizing the exposure time control.

关键词： telescopes instrumentation:spectrographs instrumentation:photometers

Modeling of Strain-Induced Precipitation Kinetics and Evolution of Austenite Grains in Nb Microalloyed Steels

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Journal of Iron and Steel Research International 2008年第3期15卷 65-69页

作者： ZHOU xiao-guang LIU Zhen-yu yuAN Xiang-qian WU Di WANG Guo-dong LIU Xiang-hua State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004 Liaoning China

Considering the effect of strain and chemical composition onprecipitation behavior, new models for the start and end time of Nb（C,N） precipitation in austenite under the conditions of different temperatures and strains have been investigated for Nb microalloyed steel. The value of n in the precipitation kinetic equation has been determined by using the available experimental data in literature, which indicated that n is a constant and independent of temperature. The values of the start and end time of the predicted precipitation are compared with the experimental values. Calculated results are in good agreement with the experimental results. Also, the evolution of austenite grains before ferrite transformation is simulated by taking the effect of precipitation into consideration. The measured austenite grain size is in good agreement with predicted one prior to ferrite transformation.

关键词： strain-induced precipitation start time precipitation static recrystallization grain size

A correction method for the telluric absorptions and application to Lijiang Observatory

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Research in Astronomy and Astrophysics 2021年第7期21卷 281-289页

作者： Kai-Xing Lu Zhi-Xiang Zhang Ying-Ke Huang An-Bing Ren Liang Xu Hai-Cheng Feng yu-Xin Xin Xu Ding xiao-guang yu Jin-Ming Bai yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Department of Astronomy Xiamen UniversityXiamen 361005China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China Department of Astronomy China West Normal UniversityNanchong 637002China

Observing a telluric standard star for correcting the telluric absorption lines of spectrum will take a significant amount of precious telescope time,especially in the long-term spectral monitoring *** that,it is difficult to select a suitable telluric standard star near in both time and airmass to the scientific *** this paper,we present a method of correcting the telluric absorption lines by combining the advantages of long slit *** rotating the slit,we observed the scientific object and a nearby comparison star in one exposure,so that the spectra of both objects should have the same telluric transmission *** telluric transmission spectrum was constructed by dividing the observed spectrum of the comparison star by its stellar template,and was used to correct the telluric absorption lines of the scientific *** the long slit spectrograph of the Lijiang 2.4-meter telescope,we designed a long-term spectroscopic observation strategy,and finished a four-year spectroscopic monitoring for a pair of objects(an active galactic nucleus and a non-varying comparison star).We applied this method to correct the telluric absorption lines of the long-term monitored spectra by the Lijiang 2.4-meter telescope,and investigated the variation of the telluric absorptions at Lijiang *** found that the telluric absorption transparency is mainly modulated by the seasonal variability of the relative humidity,airmass and *** the scatter of the [O Ⅲ] λ5007 fluxes emitted from the narrow-line region of active galactic nuclei as an indicator,we found that the correction accuracy of the telluric absorption lines is 1%.

关键词： techniques:telluric absorption methods:data analysis techniques:spectroscopic quasars:individual(SDSS J1536+0441)

Antimicrobial resistance crisis:could artificial intelligence be the solution?

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Military Medical Research 2025年第1期12卷 72-95页

作者： guang-yu Liu Dan yu Mei-Mei Fan Xu Zhang Ze-yu Jin Christoph Tang xiao-Fen Liu Department of Immunology and Pathogen Biology School of Basic Medical SciencesHangzhou Normal UniversityKey Laboratory of Aging and Cancer Biology of Zhejiang ProvinceKey Laboratory of Inflammation and Immunoregulation of HangzhouHangzhou Normal UniversityHangzhou 311121China National Key Discipline of Pediatrics Key Laboratory of Major Diseases in Children Ministry of Education Laboratory of DermatologyBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Robert and Arlene Kogod Center on Aging Mayo ClinicRochesterMN 55905USA Department of Biochemistry and Molecular Biology Mayo ClinicRochesterMN 55905USA Department of Molecular and Human Genetics Baylor College of MedicineHoustonTX 77030USA Sir William Dunn School of Pathology University of OxfordOxford OX13REUK Institute of Antibiotics Huashan HospitalFudan UniversityKey Laboratory of Clinical Pharmacology of AntibioticsNational Health Commission of the People’s Republic of ChinaNational Clinical Research Centre for Aging and MedicineHuashan HospitalFudan UniversityShanghai 200040China

Antimicrobial resistance is a global public health threat,and the World Health Organization(WHO)has announced a priority list of the most threatening pathogens against which novel antibiotics need to be *** discovery and introduction of novel antibiotics are time-consuming and *** to WHO’s report of antibacterial agents in clinical development,only 18 novel antibiotics have been approved since ***,novel antibiotics are critically *** intelligence(AI)has been rapidly applied to drug development since its recent technical breakthrough and has dramatically improved the efficiency of the discovery of novel ***,we first summarized recently marketed novel antibiotics,and antibiotic candidates in clinical *** addition,we systematically reviewed the involvement of AI in antibacterial drug development and utilization,including small molecules,antimicrobial peptides,phage therapy,essential oils,as well as resistance mechanism prediction,and antibiotic stewardship.

关键词： Antibiotic Artificial intelligence(AI) Clinical development Machine learning(ML) Antimicrobial peptide Phage therapy Antibiotic stewardship

YFPOL: A Linear Polarimeter of Lijiang 2.4 m Telescope

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Research in Astronomy and Astrophysics 2022年第9期22卷 10-34页

作者： yu-Xin Xin Jin-Ming Bai Zhong-Quan Qu Zhi Xu Ji-Rong Mao Kai Ye Bao-Li Lun Xu Ding Hong-Tao Liu yue Zhong yu-Feng Fan xiao-guang yu Liang Xu xiao-Bo Dong Jian-Guo Wang Ding-Rong Xiong yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China

Polarimetry plays an important role in investigating physical properties for celestial objects. We present a polarimeter named YFPOL for the Cassegrain focus of the Lijiang 2.4 m Telescope(LJT) of yunnan Observatories, Chinese Academy of Sciences. YFPOL is a traditional single-beam polarimeter with a rotating polarizer. As the focal-reducer instrument yunnan Faint Object Spectrograph and Camera(YFOSC) is always positioned on the Cassegrain focal plane of LJT, we develop two sets of ultra-thin(thickness <12 mm) polarizer rotation control systems with wireless charging and control functions, which are suitable for mounting on the two front-wheels of YFOSC. One set is used as the polarimetric calibration unit, and the other is for the polarimetric modulation unit. Both of the polarizers have an ultra-high contrast ratio of 1,000,000:1 in the optical band. We investigate the instrumental polarization characteristics(IPCs) in the full field of view that is transferred from YFOSC. Furthermore, we identify that the IPCs change when the Cassegrain axis rotates. The spurious polarization from the IPCs can be effectively minimized by flat-fielding using the unpolarized domeflat, when the Cassegrain rotation angle is the same or nearest to that of the polarization observation. We develop a quasiautomatic pipeline for YFPOL and its effectiveness has been verified by tests of the polarimetric observation with blazar S5 0716+714. The calibration is performed by observing the zero-polarized and highly-polarized standard stars. We successfully reach high precision polarization in the 7’ field of view, and the systematic uncertainty is below 0.8% for a V = 11.68 target with a 10 s exposure. The instrument polarization angle offset is 2°. 6. YFPOL is not only a simple polarimeter, but also a spectropolarimeter with grisms that can be considered in the future.

关键词： polarization instrumentation:polarimeters techniques:image processing techniques:polarimetric