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Palladium-Catalyzed Coupling of Propargylic Alcohols with Boronic Acids under Ambient Conditions

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Chinese Journal of Chemistry 2020年第4期38卷 372-382页

作者： Anni qin Hui Qian qin chen Shengming Ma Research Center for Molecular Recognition and Synthesis Department of ChemistryFudan University220 Handan LuShanghai 200433China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai 200032Chino

Summary of main observation and conclusion A highly eficient palladium-catalyzed direct coupling of propargylic alcohols with organoboronic acids to synthesize tri-and tetra-substituted llenes has been developed under mild reaction *** useful functional groups are tolerated in this pro-cess with high to excellent *** biological studies showed that several tri-and tetra-substituted allenes exhibited potent anti-diabetic activi-ties.

关键词： conditions. substituted Palladium

3D printing of cell-delivery scaffolds for tissue regeneration Jianmin Xue and others

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Regenerative Biomaterials 2023年第1期10卷 839-852页

作者： Jianmin Xue chen qin chengtie Wu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Tissue engineering strategy that combine biomaterials with living cells has shown special advantages in tissue regeneration and promoted the development of regenerative *** particular,the rising of 3D printing technology further enriched the structural design and composition of tissue engineering scaffolds,which also provided convenience for cell loading and cell delivery of living *** this review,two types of cell-delivery scaffolds for tissue regeneration,including 3D printed scaffolds with subsequent cell-seeding and 3D cells bioprinted scaffolds,are mainly *** devote a major part to present and discuss the recent advances of two 3D printed cell-delivery scaffolds in regeneration of various tissues,involving bone,cartilage,skin tissues *** two types of 3D printed cell-delivery scaffolds have some shortcomings,they do have generally facilitated the exploration of tissue engineering scaffolds in multiple tissue *** is expected that 3D printed cell-delivery scaffolds will be further explored in function mechanism of seeding cells in vivo,precise mimicking of complex tissues and even organ reconstruction under the cooperation of multiple fields in future.

关键词： cell-delivery 3D printing tissue regeneration

Does a General Temperature-Dependent Q10 Model of Soil Respiration Exist at Biome and Global Scale？

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Journal of Integrative Plant Biology 2005年第11期47卷 1288-1302页

作者： Hua chen Han-qin TIAN School of Forestry and Wildlife Sciences Auburn University Auburn AL 36849 USA

Soil respiration （SR） is commonly modeled by a Q10 （an indicator of temperature sensitivity） function in ecosystem models. Q10 is usually treated as a constant of 2 in these models, although Q10 value of SR often decreases with increasing temperatures. It remains unclear whether a general temperature- dependent Q10 model of SR exists at biome and global scale. In this paper, we have compiled the long-term Q10 data of 38 SR studies ranging from the Boreal, Temperate, to Tropical/Sublropical biome on four continents. Our analysis indicated that the general temperature-dependent biome Q10 models of SR existed, especially in the Boreal and Temperate biomes. A single-exponential model was better than a simple linear model in fitting the average Q10 values at the biome scale. Average soil temperature is a better predictor of Q10 value than average air temperature in these models, especially in the Boreal biome. Soil temperature alone could explain about 50% of the Q10 variations in both the Boreal and Temperate biome single-exponential Q10 model. Q10 value of SR decreased with increasing soil temperature but at quite different rates among the three biome Q10 models. The k values （Q10 decay rate constants） were 0.09, 0.07, and 0.02/℃ in the Boreal, Temperate, and Tropical/Subtropical biome, respectively, suggesting that Q10 value is the most sensitive to soil temperature change in the Boreal biome, the second in the Temperate biome, and the least sensitive in the Tropical/ Subtropical biome. This also indirectly confirms that acclimation of SR in many soil warming experiments probably occurs. The k value in the ＂global＂ single-exponential Q10 model which combined both the Boreal and Temperate biome data set was 0.08/℃. However, the global general temperature-dependent Q10 model developed using the data sets of the three biomes is not adequate for predicting Q10 values of SR globally. The existence of the general temperature-dependent Q10 models of SR in the Boreal and Temp

关键词： air temperature biome Q10 model global Q10 model simple linear model single-exponentialmodel soil respiration (SR) soil temperature temperature sensitivity (Q10).

Perception and Recognition of Vocalization in Anuran Mate Choice

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Asian Herpetological Research 2020年第4期11卷 394-400页

作者： Fang LU Yezhong TANG qin chen Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041SichuanChina chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina

Vocal communications in frogs and toads have been highly diversified and become a hot topic in the fields of herpetology,ecology,and behavioral *** present short review summarized several interesting phenomena of vocal communication found mainly in anurans that might contribute to the individual identification of mates or rivals,including call matching,aggressive signaling,acoustic complexity,signal exaggeration,the first note effect and left hemisphere *** on the perception and recognition of vocal communications will facilitate our comprehension of the adaptive mechanisms and evolutionary paths of anuran signaling *** proposed here that comparative studies on acoustic signal structures,codes of sender status,and auditory neural responses based on phylogenetic relationships across species can highlight further the evolutionary trajectory in anurans.

关键词： anuran adaptive mechanism evolution phonotaxis vocal communication

Properties on Solutions of Some q-Difference Equations

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1877-1886页

作者： Bao qin chen Zong Xuan chen Sheng LI School of Mathematical Sciences South China Normal University Guangzhou 510631 P. R. China

We consider the properties on solutions of some q-difference equations of the form ∑ n j=0 aj（z）f（qj z）=an＋1（z）, where a0（z）,..., an＋1（z） are meromorphic functions, a0（z）an（z） ≠ 0 and q ∈ C such that 0 〈｜q｜ ≤ 1. We give estimates on the upper bound for the length of the gap in the power series of entire solutions of （＊） when the coefficients a0（z）,..., an＋1（z） are polynomials and 0 〈｜q｜〈 1. For some special cases, we give estimates of growth of f（z）. And we also show that the case 0 〈｜q｜〈 1 is different from the case ｜q｜=1.

关键词： q-difference equation entire coefficient Fabry gap growth

Relationship between CME velocities and X-ray fluxes of associated flares

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 470-474页

作者： An-qin chen Wei-Guo Zong National Center for Space Weather China Meteorological Administration Beijing 100081 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100080 China

Coronal mass ejection （CME） velocities have been studied over recent decades. We present a statistical analysis of the relationship between CME velocities and X-ray fluxes of the associated flares. We study two types of CMEs. One is the FL type associated only with flares, while the other is the intermediate type associated with both filament eruptions and flares. It is found that the velocities of the FL type CMEs are strongly correlated with both the peak and the time-integrated X-ray fluxes of the associated flares. However, the correlations between the intermediate type CME velocities and the corre- sponding two parameters are poor. It is also found that the correlation between the CME velocities and the peak X-ray fluxes is stronger than that between the CME velocities and the time-integrated X-ray fluxes of the associated flares.

关键词： Sun coronal mass ejections (CMEs)-Sun flares-Sun filaments

General Decay for a Thermoelastic Problem of a Microbeam with Gurtin-Pipkin Thermal Law

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 426-440页

作者： Dong-qin chen Wen-jun LIU Zhi-jing chen School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

In this paper,we study the well-posedness and the asymptotic stability of a one-dimensional thermoelastic microbeam system,where the heat conduction is given by Gurtin-Pipkin thermal *** first establish the well-posedness of the system by using the semigroup arguments and Lumer-Phillips *** then obtain an explicit and general formula for the energy decay rates through perturbed energy method and some properties of the convex functions.

关键词： microbeam system Gurtin-Pipkin thermal law well-posedness general decay

Fertility control of Rattus nitidus using quinestrol:effects on reproductive organs and social behavior

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Integrative Zoology 2013年第1期8卷 9-17页

作者： Quansheng LIU Jiao qin qin chen Deng WANG Dazhao SHI Guangdong Entomological Institute GuangzhouChina College of Agronomy and Biotechnology China Agricultural UniversityBeijingChina Guangdong Provincial Public Laboratory on Wild Animal Conservation and Management GuangzhouChina

Fertility control has been identified by studies in the laboratory and the field as a more appropriate and long-term control strategy for rodent pests than lethal *** this study,we investigated the effects of quinestrol on mass of reproductive organs and on social behaviors in female and male Himalayan field rats(Rattus nitidus).A total of 16 adult females and 16 adult males were randomly assigned to 4 *** male and one female group were fed rice with 0.005%quinestrol by weight for 7 days,and another 2 groups were fed rice *** 7 days,rats were assigned to 10 min dyadic encounters between groups,and investigation,aggression,defense and attack latency were *** animals were killed on day 10,and reproductive organs were dissected and *** encounter data showed that there were obvious changes in social behaviors of quinestrol-treated *** significantly inhibited the investigative behavior of quinestrol-treated males toward control females in Rattus nitidus,but seldom affected investigation between control males and quinestrol-treated *** of control females toward quinestrol-treated males was higher than that of quinestrol-treated females,and defense of quinestrol-treated males toward control females was more remarkable than that of control *** remarkably decreased wet masses of epididymis and spermotophore in males and ovaries in females,but had no effect on wet masses of testes and uteri after quinestrol *** results indicate that the anti-fertility effects of quinestrol on *** are attributed to not only suppressing reproductive organs but also impacting social behaviors associated with territory defense and mate choice.

关键词： fertility control quinestrol Rattus nitidus rodent pest social behavior

Upper Cretaceous alluvial fan deposits in the Jianglangshan Geopark of Southeast China:implications for bedrock control on Danxia landform evolution

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Journal of Mountain Science 2017年第5期14卷 926-935页

作者： chen Liu-qin GUO Fu-sheng State Key Laboratory Breeding Base of Nuclear Resources and Environment East China University of TechnologyNanchang 330013 China School of Earth Sciences East China University of Technology Nanehang 330013 China

The Jianglangshan Geopark in the western Zhejiang Province of Southeast China is well-known for its spectacular red-colored sandstone landforms. Little is known about the depositional processes of the conglomerate-dominated Fangyan Formation, the lithologic base of the Danxia landforms in this geopark. Based on detailed field investigation of lithology, sedimentary structures, bed thickness and geometry, five facies are recognized: facies A(matrixsupported cobble conglomerate), facies B(pebble conglomerate), facies C(pebbly sandstone), facies D(fine-grained sandstone) and facies E(mudstone). The results show that streamflow-dominated fans were the main depositional processes responsible for the accumulation of the Fangyan Formation along the mountain fronts. These fan conglomerates form the base for the evolution of the Danxia landscapes owing to the uplift and erosion of the study area. In contrast, the fine-grained sedimentary successions produced by fluvial floodplains in the distal part of the fans were thinner and more easily weathered. Such sedimentary facies distribution patterns were thought to be similar during Late Cretaceous across Southeast China. The Danxia landforms are largely the geographical expressions of the conglomerate-dominated redbeds in the proximal-middle fans.

关键词： Danxia landform Late Cretaceousredbeds Alluvial fan Jianglangshan Geopark Landscape evolution