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The functional significance of residual yolk in lizards

Current Zoology 2023年第2期69卷 192-199页

作者： kun Guo Cai-Feng Wang yu du Yan-Fu Qu Florentino Brana Xiang Ji Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection College of Life and Environmental SciencesWenzhou UniversityWenzhou 325035ZhejiangChina Hainan Key Laboratory of Herpetological Research College of Fisheries and Life ScienceHainan Tropical Ocean UniversitySanya 572022HainanChina College of Life Sciences Nanjing Normal UniversityNanjing 210023China Departamento de Biologia de Orgar smos v Sistemas.Universidad de 0viedo Oviedo 33071Spain

Residual yolk is assumed to be an important source of energy and nutrients during early life in nonmammalian amniotes.Available data show that the mean size of residual yolk is far smaller in lizards than in turtles,snakes,crocodiles,and birds,raising a question of whether residual yolk is of functional significance in lizards.Here,we compared data from 26 lizard species with those from other nonmammalian amniotes to test the hypothesis that residual yolk is functionally less significant in species producing more fully developed offspring.In our sample,species mean offspring water contents ranged from 73%to 84%of body wet mass;species mean proportions of carcass dry mass,fat-body dry mass,and residual yolk dry mass to offspring dry mass ranged from 84%to 99%,0%to 5.0%,and 0%to 14.4%,respectively.Lizards are,on average,more fully developed at hatching or birth than snakes,as revealed by the fact that the mean proportion of carcass dry mass to body dry mass and offspring water contents were both higher in lizards than in snakes.We conclude that the functional significance of residual yolk during early life is generally less evident in lizards.Even in the lizards where residual yolk is of potential functional significance,this portion of yolk contributes little,if any,to postembryonic growth.Future work could usefully collect data across a wider spectrum of reptile taxa to establish a precocial-altricial continuum and test the hypothesis that species with a smaller amount of residual yolk are closer to the precocial end of the continuum.

关键词： carcass fatbody lizards offspring postembryonicgrowth residual yolk

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Comparison of structural and physicochemical properties of potato protein and potato flour modified with tyrosinase

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Journal of Integrative Agriculture 2022年第5期21卷 1513-1524页

作者： ZHU yu yuAN yu-han MEI Li-ping DING Shuang-kun GAO yu-chen du Xian-feng GUO Li Anhui Engineering Laboratory of Agro-products Processing Anhui Agricultural UniversityHefei 230036P.R.China State Key Laboratory of Biobased Material and Green Papermaking School of Food Sciences and EngineeringQilu University of Technology(Shandong Academy of Sciences)Jinan 250353P.R.China College of Life Science and Technology Xinjiang UniversityUrumchi 830046P.R.China

The present study modified potato protein and flour with tyrosinase to promote the diversification of potato staple foods.The results indicated that tyrosinase treatment markedly altered the secondary structure of proteins.After tyrosinase treatment,the maximum decomposition temperature of potato protein and flour increased from 322.32 to 332.40℃ and from 294.24 to 299.61℃,respectively.Tyrosinase treatment remarkably reduced the pasting viscosity of potato flour,that is,the peak viscosity,through reducing viscosity,breakdown,final viscosity,and setback by 32.50,60.98,13.04,68.24,and 74.31%,respectively.In contrast,tyrosinase treatment increased the shear resistance and hardness of the protein and flour gels;the maximum stress values of the protein and flour gels increased from 1.48 to 10.1% and from 6.87 to 14.8%,respectively.Furthermore,tyrosinase treatment promoted viscoelastic properties and structural stability of potato protein and flour.These results may provide an important foundation for the development of novel potato staple foods.

关键词： potato protein starch structural tyrosinase physicochemical features

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Shock initiation performance of NTO-based polymer bonded explosive

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Defence Technology（防务技术） 2022年第9期18卷 1538-1545页

作者： Peng-song Nie Shao-hua Jin Li-xiao-song du Li-jie Li kun Chen yu Chen Rui yu School of Materials Science and Engineering Beijing Institute of TechnologyZhongguancun South Street 5Beijing100081China Xi'an Modern Control Technology Research Institute Xi'an710065China

3-nitro-1,2,4-tri-azol-5-one(NTO) is a high energy insensitive explosive. To study the shock initiation process of NTO-based polymer bonded explosive JEOL-1(32%octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX), 32% NTO, 28% Al and 8% binder system), the cylinder test, the gap experiments and numerical simulation were carried out. Firstly, we got the detonation velocity(7746 m/s) and the parameters of Jones-Wilkins-Lee(JWL) equation of state(EOS) for detonation product by cylinder test and numerical simulation. Secondly, the Hugoniot curve of unreacted explosive for JEOL-1 was obtained calculating the data of pressure and time at different Lagrangian positions. Then the JWL EOS of unreacted explosive was obtained by utilizing the Hugoniot curve as the reference curve. Finally, we got the pressure growth history of JEOL-1 under shock wave stimulation and the parameters of the ignition and growth reaction rate equation were obtained by the pressure-time curves measured by the shockinitiation gap experiment and numerical simulation. The determined trinomial ignition and growth model(IG model) parameters can be applied to subsequently simulation analysis and design of insensitive ammunition with NTO-based polymer bonded explosive.

关键词： NTO Shock initiation Hugoniot data JWL Ignition and growth reactive model

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DETERMINATION OF ROCK-BREAKING PERFORMANCE OF HIGH-PRESSURE SUPERCRITICAL CARBON DIOXIDE JET

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Journal of Hydrodynamics 2012年第4期24卷 554-560页

作者： du yu-kun WANG Rui-he NI Hong-jian LI Mu-kun SONG Wei-qiang SONG Hui-fang College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China

In this study, a well-designed experimental setup is used to determine the rock-breaking performance of a high-pressure supercritical carbon dioxide （SC-CO2） jet. Its rock-breaking performance is first compared with that of a high-pressure water jet under the same operation conditions. The effects of five major factors that affect the rock-breaking performance of the high-pressure SC-CO2 jet, i.e., the nozzle diameter, the standoff distance, the jet pressure, the rock compressive strength and the jet temperature are experimentally determined. The experimental results indicate that the rock-breaking performance of the SC-CO2 jet is significantly improved over the high-pressure water jet. It is also found that the rock-breaking performance of the SC-CO2 jet is improved with the increase of the nozzle diameter or the standoff distance, until the nozzle diameter or the standoff distance reaches a certain critical value and after that it begins to deteriorate. The rock-breaking performance of the SC-CO2 jet improves monotonically with the increase of the jet pressure, while it shows a monotonic deterioration with the increase of the rock compressive strength. In addition, it is found that, under the same working conditions, the SC-CO2 jet can always provide a better rock-breaking performance than the subcritical liquid CO2 jet.

关键词： supercritical carbon dioxide drilling engineering rock-breaking performance

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Recent advances in isolation,identification,and culture of mammalian spermatogonial stem cells

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Asian Journal of Andrology 2022年第1期24卷 5-14页

作者： Hua-Ming Xi Yi-Jie Ren Fa Ren yu Li Tian-yu Feng Zhi Wang Ye-Qing du Li-kun Zhang Jian-Hong Hu Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest Agriculture and Forestry UniversityYangling 712100China

Continuous spermatogenesis depends on the self-renewal and differentiation of spermatogonial stem cells(SSCs).SSCs,the only male reproductive stem cells that transmit genetic material to subsequent generations,possess an inherent self-renewal ability,which allows the maintenance of a steady stem cell pool.SSCs eventually differentiate to produce sperm.However,in an in vitro culture system,SSCs can be induced to differentiate into various types of germ cells.Rodent SSCs are well defined,and a culture system has been successfully established for them.In contrast,available information on the biomolecular markers and a culture system for livestock SSCs is limited.This review summarizes the existing knowledge and research progress regarding mammalian SSCs to determine the mammalian spermatogenic process,the biology and niche of SSCs,the isolation and culture systems of SSCs,and the biomolecular markers and identification of SSCs.This information can be used for the effective utilization of SSCs in reproductive technologies for large livestock animals,enhancement of human male fertility,reproductive medicine,and protection of endangered species.

关键词： culture identification isolation male germline stem cell spermatogonial stem cell transplantation

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Validation of the Simplified Chinese-character Version of the International Physical Activity Questionnaire-Long Form in Urban Community-dwelling Adults:a Cross-sectional Study in Hangzhou,China

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Biomedical and Environmental Sciences 2017年第4期30卷 255-263页

作者： REN Yan Jun SU Meng LIU Qing Min TAN Ya yun DU Yu Kun LI Li Ming Lyu Jun Department of Chronic Non-communicable Disease Control and Prevention Hangzhou Center for Disease Control and Prevention National Clinical Research Center of Cardiovascular Diseases State Key Laboratory of Cardiovascular DiseaseFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical College Department of Epidemiology and Biostatistics School of Public HealthPeking University

Objective To assess the test-retest reliability and criterion validity of the Simplified Chinese-character version of the International Physical Activity Questionnaire Long form （IPAC）.-L） in urban community-dwelling adults in Hanghzou, China. Methods A total of 158 eligible participants aged 25-59 years from 6 neighbourhoods in two central districts of Hangzhou completed the IPAQ-L questionnaire twice within a 7-day interval. Half of the subjects wore pedometers during the first 7 days. Test-retest reliability was examined by comparing the first （Day 1） and the second （Day 9） survey of IPAQ-L Criterion validity was assessed by comparing IPAO,-L with pedometer data. Results Modest to good test-retest reliability was found with intraclass correlation coefficients of 0.67 for total PA, 0.37 to 0.73 for specific dimensions, and 0.56 to 0.71 for different intensities of PA. Total PA measured by IPAO.-L was moderately correlated with exercise levels （partial r = 0.27, P = 0.020） and walking distance （partial r = 0.31, P = 0.007）, which were measured by a pedometer, after adjusting for gender, age, educational attainment and employment status. Conclusion Our results indicate that the IPAO.-L is a reliable and validated measure for assessing physica activity levels in this population and possibly the adult population in other mainland Chinese cities.

关键词： PAO. Long form China Physical activity Reliability Validity Pedometer

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Co-splitting of Simple Lie Algebras of Type A, D, E

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Communications in Mathematical Research 2015年第3期31卷 229-241页

作者： Zhao yu-e du Xian-kun School of Mathematics Qingdao University

In this paper, through a meticulous description of finite root system,a concrete comultiplication with an explicit action on the basis elements of finitedimensional simple Lie algebras of type A; D; E is constructed. Then any finitedimensional simple Lie algebra of type A; D; E is endowed with a new generalizedLie coalgebra splitting. This construction verifies the known existence of a co-splitLie structure on any finite dimensional complex simple Lie algebra.

关键词： Lie coalgebra co-splitting finite-dimensional simple Lie algebra

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Cocrystal virtual screening based on the XGBoost machine learning model

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中国化学快报:英文版 2023年第8期34卷 398-403页

作者： Dezhi Yang Li Wang Penghui yuan Qi An Bin Su Mingchao yu Ting Chen kun Hu Li Zhang Yang Lu Guanhua du Beijing City Key Laboratory of Polymorphic Drugs Center of Pharmaceutical PolymorphsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Shandong Soteria Pharmaceutical Co. Ltd.Laiwu 271100China Beijing City Key Laboratory of Drug Target and Screening Research National Center for Pharmaceutical ScreeningInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Co-crystal formation can improve the physicochemical properties of a compound,thus enhancing its druggability.Therefore,artificial intelligence-based co-crystal virtual screening in the early stage of drug development has attracted extensive attention from researchers.However,the complexity of developing and applying algorithms hinders it wide application.This study presents a data-driven co-crystal prediction method based on the XGBoost machine learning model of the scikit-learn package.The simplified molecular input line entry specification(SMILES)information of two compounds is simply inputted to determine whether a co-crystal can be formed.The data set includs the co-crystal records presented in the Cambridge Structural Database(CSD)and the records of no co-crystal formation from extant literature and experiments.RDKit molecular descriptors are adopted as the features of a compound in the data set.The developed model shows excellent performance in the proposed co-crystal training and validation sets with high accuracy,sensitivity,and F1 score.The prediction success rate of the model exceeds 90%.The model therefore provides a simple and feasible scheme for designing and screening co-crystal drugs efficiently and accurately.

关键词： Cocrystal Machine learning XGBoost Molecular descriptor Praziquantel Nefiracetam

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Crystal Structures, Stability, and Solubility Evaluation of a 2:1 Diosgenin-Piperazine Cocrystal

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Natural Products and Bioprospecting 2020年第4期10卷 261-267页

作者： Ningbo Gong Hongmei yu Ying Wang Cheng Xing kun Hu Guanhua du Yang Lu Beijing Key Laboratory of Polymorphic Drugs Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Beijing City Key Laboratory of Drug Target Identification and Drug Screening Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

A cocrystal of diosgenin with piperazine in 2:1 stoichiometry was successfully synthesized.The solid form was prepared by liquid assisted grinding,slurry and crystallization methods.The cocrystal was characterized by powder X-ray diffraction,differential scanning calorimetry,thermogravimetric analysis,Fourier transform infrared spectroscopy,and structure determined by single crystal X-ray diffraction,the hydrogen bonds formed into fish bone structure along the[010]direction and all the molecules packed into 3D layer structure along a axis.After formation of cocrystal,the solubility of diosgenin was improved,and the solubility value in 0.2%SDS solution was approximately 1.5 times as large as that of the parent material.

关键词： Diosgenin Piperazine Cocrystal Characterization Solubility

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A Note on Comparison Between the Wiener Index and the Zagreb Indices

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Communications in Mathematical Research 2018年第4期34卷 296-302页

作者： YOU ZHI-FU HUANG yu-FEI du Xian-kun School of Computer Science Guangdong Polytechnic Normal UniversityGuangzhou510665 Department of Mathematics Teaching Guangzhou Civil Aviation CollegeGuangzhou510403 不详

In this note, we correct a wrong result in a paper of Das et al. with regard to the comparison between the Wiener index and the Zagreb indices for trees （Das K C, Jeon H, Trinajstic N. The comparison between the Wiener index and the Zagreb indices and the eccentric connectivity index for trees. Discrete Appl. Math., 2014, 171：35 41）, and give a simple way to compare the Wiener index and the Zagreb indices for trees. Moreover, the comparison between the Wiener index and the Zagreb indices for unicyclic graphs is carried out.

关键词： Wiener index Zagreb indice tree unicyclic graph

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