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| 1 | Structural Synthesis of a Class of 2R2T Hybrid Mechanisms显示文摘Conventional overconstrained parallel manipulators have been widely studied both in industry and academia,however the structural synthesis of hybrid mechanisms with additional constraints is seldom studied,especially for the four degrees of freedom(DOF) hybrid mechanisms.In order to develop a manipulator with additional constraints,a class of important spatial mechanisms with coupling chains(CCs) whose motion type is two rotations and two translations(2R2T) is presented.Based on screw theory,the combination of different types of limbs which are used to construct parallel mechanisms and coupling chains is proposed.The basic types of the general parallel mechanisms and geometric conditions of the kinematic chains are given using constraint synthesis method.Moreover,the 2R2T motion pattern hybrid mechanisms which are derived by adding coupling chains between different serial kinematic chains(SKCs) of the corresponding parallel mechanisms are presented.According to the constraint analysis of the mechanisms,the movement relationship of the moving platform and the kinematic chains is derived by disassembling the coupling chains.At last,fourteen novel hybrid mechanisms with two or three serial kinematic chains are presented.The proposed novel hybrid mechanisms and construction method enrich the family of the spatial mechanisms and provide an instruction to design more complex hybrid mechanisms. | TIAN Chunxu FANG Yuefa GUO Sheng | 2016 | Chinese Journal of Mechanical Engineering2016，29，4： | 5 |
| 2 | First experimental constraints on WIMP couplings in the effective field theory framework from CDEX显示文摘We present weakly interacting massive particles(WIMPs) search results performed using two approaches of effective field theory from the China Dark Matter Experiment(CDEX), based on the data from both CDEX-1B and CDEX-10 stages. In the nonrelativistic effective field theory approach, both time-integrated and annual modulation analyses were used to set new limits for the coupling of WIMP-nucleon effective operators at 90% confidence level(C.L.) and improve over the current bounds in the low mχregion. In the chiral effective field theory approach, data from CDEX-10 were used to set an upper limit on WIMP-pion coupling at 90% C.L. We for the first time extended the limit to the m_(χ)<6 GeV/c^(2) region. | Yi Wang Zhi Zeng Qian Yue LiTao Yang KeJun Kang YuanJing Li Mehment Agartioglu HaiPeng An JianPing Chang JingHan Chen YunHua Chen JianPing Cheng Cheng Yi Chiang WenHan Dai Zhi Deng ChangHao Fang XinPing Geng Hui Gong QiuJu Guo XuYuan Guo HongJian He Li He ShengMing He JinWei Hu TuChen Huang HanXiong Huang HaiTao Jia LiPing Jia Xi Jiang HauBin Li JianMin Li Jin Li MingXuan Li RenMingJie Li Xia Li YuLan Li Bin Liao FongKay Lin ShinTed Lin ShuKui Liu YanDong Liu Yu Liu YuanYuan Liu ZhongZhi Liu Hao Ma YuCai Mao QiYuan Nie JinHua Ning Hui Pan NingChun Qi Jie Ren XiChao Ruan ChangSong Shang Vivek Sharma Ze She Lakhwinder Singh Monoj Kumar Singh TianXi Sun ChangJian Tang WeiYou Tang Yang Tian GuangFu Wang Li Wang Qing Wang Yu Chen Wang YunXiang Wang Zhen Wang Henry Tsz-King Wong ShiYong Wu YuCheng Wu HaoYang Xing Yin Xu Tao Xue YuLu Yan Nan Yi ChunXu Yu HaiJun Yu JianFeng Yue Ming Zeng BingTao Zhang Lei Zhang FengShou Zhang ZhenYu Zhang KangKang Zhao MingGang Zhao JiFang Zhou ZuYing Zhou JingJun Zhu | 2021 | Science China(Physics,Mechanics & Astronomy)2021，64，8： | 3 |
| 3 | Human activity during the late Pleistocene in the Lop Nur region, northwest China: Evidence from a buried stone artifact显示文摘The Lop Nur region, in the east part of Tarim Basin, was an important transportation junction between west and east,north and south Eurasia. However, previous studies on prehistoric human activity have concentrated mostly on the Bronze Age,whereas that during the Stone Age remains largely unresearched. Here, we present a new direct evidence of human activity in the late Pleistocene, recorded on a grinding stone buried in a lacustrine sediment section of the Lop Nur region. The grain size distribution of the sediment section indicates that the site was probably in the center of a lake with weak hydrodynamic environment. Therefore, the stone artifact can only be carried to here by people instead of river and it was never move as soon as left here. Results of radiocarbon dating, the evident stratigraphic relations between the stone artifact and the sedimentary formation, indicate that the human activity could extend to approximately 13 ka BP. Furthermore, the results of starch-grain and use-wear analyses suggest that ancient humans gathered seeds of Triticeae, roots, and tubers and used the grinding stone to simply process selected plant as plant foodstuffs during this period. It implies that the environmental conditions in the river delta of the Lop Nur were inhabitable during the late Pleistocene. | Kangkang LI Xiaoguang QIN Xiaoyan YANG Bing XU Lei ZHANG Guijin MU Dong WEI Chunxue WANG Yong WU Xiaohong TIAN Yongchong LIN Wen LI Jiaqi LIU Yinxin JIAO | 2018 | Science China Earth Sciences2018，61，11： | 1 |
| 4 | A hydrogel spinal dural patch with potential anti-inflammatory,pain relieving and antibacterial effects显示文摘CSFL caused by spinal dural defect is a common complication of spinal surgery,which need repair such as suture or sealants.However,low intracranial pressure symptoms,wound infection and prolonged hospital associated with pin-hole leakage or loose seal effect were often occurred after surgical suture or sealants repair.Stable,pressure resistance and high viscosity spinal dural repair patch in wet environment without suture or sealants was highly needed.Herein,a bioactive patch composed of alginate and polyacrylamide hydrogel matrix cross-linked by calcium ions,and chitosan adhesive was proposed.This fabricated patch exhibits the capabilities of promoting defect closure and good tight seal ability with the bursting pressure is more than 790 mm H2O in wet environment.In addition,the chitosan adhesive layer of the patch could inhibit the growth of bacterial in vitro,which is meaningful for the postoperative infection.Furthermore,the patch also significantly reduced the expression of GFAP,IBA-1,MBP,TNF-α,and COX-2 in early postoperative period in vivo study,exerting the effects of anti-inflammatory,analgesic and adhesion prevention.Thus,the bioactive patch expected to be applied in spinal dural repair with the good properties of withstanding high pressure,promoting defect closure and inhibiting postoperative infection. | Jiahao Li Jingjing Tian Chunxu Li Longyun Chen Yu Zhao | 2022 | Bioactive Materials2022，7，8： | 0 |
| 5 | Functional conservation and divergence of miR156 and miR529 during rice development显示文摘MicroRNAs(miRNAs)are important regulatory elements involved in the regulation of various plant developmental and physiological processes by blocking the expression of target genes.MiR156 and miR529 are two combinatorial regulators,which cooperatively target the SQUAMOSA PROMOTER BINDING-LIKE(SPL)family genes.However,there has been no report about the functional conservation and divergence of miR156 and miR529 during plant development to date.In this study,the biological function and relationship of miR156,miR529 and their target Os SPL14 in rice were explored.Overexpression of miR156e or miR529a(miR156e-OE and miR529a-OE)increased the grain size and tiller number but decreased the plant height and panicle length,while an opposite phenotype was observed for their target mimicry(miR156-MIMIC and miR529a-MIMIC)transgenic plants.Stem-loop RT-PCR results revealed ubiquitous expression of miR156 in roots,axillary buds and leaves,while miR529 was preferentially expressed in the panicle.Accordingly,Os SPL14 could be preferentially and precisely cleaved by miR529a in young panicle but by miR156 in vegetative tissues.Transgenic plants generated by the target immune strategy exhibited obvious growth defects upon the blocking of miR156 and/or miR529 function in rice,confirming that both miR156 and miR529 play important roles in controlling rice growth and development.Moreover,the miR156/miR529-Os SPL14 module negatively controlled grain size by regulating the genes associated with grain size and cell cycling,and controlled plant height through a more complicated mechanism.Taken together,our results demonstrate that miR156 and miR529 respectively function dominantly in the vegetative stage and reproductive stage to control rice growth and development by regulating the accumulation of Os SPL14.These findings facilitate a better understanding of the functional conservation and divergence of miR156 and miR529 family in the miRNA combinatorial regulatory network of plants. | Yan Li Yizhou He Tian Qin Xuelian Guo Kun Xu Chunxue Xu Wenya Yuan | 2023 | The Crop Journal2023，11，3： | 0 |
| 6 | Performances of a prototype point-contact germanium detector immersed in liquid nitrogen for light dark matter search显示文摘The CDEX-10 experiment searches for light weakly interacting massive particles, a form of dark matter, at the China Jinping Underground Laboratory, where approximately 10 kg of germanium detectors are arranged in an array and immersed in liquid nitrogen. Herein, we report on the experimental apparatus, detector characterization, and spectrum analysis of one prototype detector. Owing to the higher rise-time resolution of the CDEX-10 prototype detector as compared with CDEX-1 B, we identified the origin of an observed category of extremely fast events. For data analysis of the CDEX-10 prototype detector, we introduced and applied an improved bulk/surface event discrimination method. The results of the new method were compared to those of the CDEX-1 B spectrum. Both sets of results showed good consistency in the 0-12 ke Vee energy range, except for the 8.0 keV K-shell X-ray peak from the external copper. | Hao Jiang LiTao Yang Qian Yue KeJun Kang JianPing Cheng YuanJing Li Henry Tsz-King Wong M.A?artio?lu HaiPeng An JianPing Chang JingHan Chen YunHua Chen Zhi Deng Qiang Du Hui Gong Li He Jin Wei Hu QingDong Hu HanXiong Huang LiPing Jia HauBin Li Hong Li Jian Min Li Jin Li Xia Li XueQian Li YuLan Li Bin Liao FongKay Lin ShinTed Lin ShuKui Liu YanDong Liu YuanYuan Liu ZhongZhi Liu Hao Ma JingLu Ma Hui Pan Jie Ren XiChao Ruan B.Sevda Vivek Sharma ManBin Shen Lakhwinder Singh Monoj Kumar Singh TianXi Sun ChangJian Tang WeiYou Tang Yang Tian GuangFu Wang JiMin Wang Li Wang Qing Wang Yi Wang ShiYong Wu YuCheng Wu HaoYang Xing Yin Xu Tao Xue SongWei Yang Nan Yi ChunXu Yu HaiJun Yu JianFeng Yue XiongHui Zeng Ming Zeng Zhi Zeng FengShou Zhang YunHua Zhang MingGang Zhao JiFang Zhou ZuYing Zhou JingJun Zhu ZhongHua Zhu | 2019 | Science China(Physics,Mechanics & Astronomy)2019，62，3： | 0 |
| 7 | Continuously released Zn^(2+)in 3D-printed PLGA/β-TCP/Zn scaffolds for bone defect repair by improving osteoinductive and anti-inflammatory properties显示文摘Long-term nonunion of bone defects has always been a major problem in orthopedic treatment.Artificial bone graft materials such as Poly(lactic-co-glycolic acid)/β-tricalcium phosphate(PLGA/β-TCP)scaffolds are expected to solve this problem due to their suitable degradation rate and good osteoconductivity.However,insufficient mechanical properties,lack of osteoinductivity and infections after implanted limit its large-scale clinical application.Hence,we proposed a novel bone repair bioscaffold by adding zinc submicron particles to PLGA/β-TCP using low temperature rapid prototyping 3D printing technology.We first screened the scaffolds with 1 wt%Zn that had good biocompatibility and could stably release a safe dose of zinc ions within 16 weeks to ensure long-term non-toxicity.As designed,the scaffold had a multi-level porous structure of biomimetic cancellous bone,and the Young’s modulus(63.41±1.89 MPa)and compressive strength(2.887±0.025 MPa)of the scaffold were close to those of cancellous bone.In addition,after a series of in vitro and in vivo experiments,the scaffolds proved to have no adverse effects on the viability of BMSCs and promoted their adhesion and osteogenic differentiation,as well as exhibiting higher osteogenic and anti-inflammatory properties than PLGA/β-TCP scaffold without zinc particles.We also found that this osteogenic and anti-inflammatory effect might be related to Wnt/β-catenin,P38 MAPK and NFkB pathways.This study lay a foundation for the follow-up study of bone regeneration mechanism of Zn-containing biomaterials.We envision that this scaffold may become a new strategy for clinical treatment of bone defects. | Chunxu Li Fengbo Sun Jingjing Tian Jiahao Li Haidan Sun Yong Zhang Shigong Guo Yuanhua Lin Xiaodan Sun Yu Zhao | 2023 | Bioactive Materials2023，，6： | 0 |
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