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Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ... Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined. 展开更多
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
Evidence for the decays of ∧c^+→∑^+η and ∑^+η’
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作者 麦迪娜 M.N.Achasov +146 位作者 S.Ahmed M.Albrecht M.Aleksee A.Amoroso 安芬芬 安琪 白羽 O.Bakina R. Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 O.Cakir A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈平亮 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 段鹏飞 范荆州 方建 房双世 方易 R.Farinelli L.Fava S.Fegan F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 T.Hussain N.Hu sken W.Ikegami Andersson M.Irshad 纪全 姬清平 季晓斌 季筱璐 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson A.Julin N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kornicer M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kuhn J.S.Lange P.Larin L.La 《中国物理C:英文版》 SCIE CAS CSCD 2019年第8期15-23,共9页
We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII col... We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays ∧^+→∑^+η and ∑^+η' and with statistical significance of and , respectively. Normalizing to the reference decays ∧^+→∑^+π^0 and ∑^+ω, we obtain the ratios of the branching fractions B(∧C^+→∑^+η)/V(∧^→∑^+π^0)and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)to be and , respectively. The upper limits at the 90% confidence level are set to be B(∧C^→∑^+η)/V(∧^+→∑^+π^0)<0.58 and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)<1.2. Using BESIII measurements of the branching fractions of the reference decays, we determine B(∧C^+→∑^+η)=(0.41±019±0.05)%(<0.68%) and B(∧C^+→∑^+η)=(1.34+0.53+0.19)%(<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching fraction of ∧C^+→∑^+η is consistent with the previous measurement, and the branching fraction of ∧C^+→∑^+η is measured for the first time. 展开更多
关键词 charmed BARYON ∧c^+ DECAYS branching FRACTIONS
Adaptive multi-resolution Modularity for detecting communities in networks
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作者 Shi Chen Zhi-Zhong Wang +5 位作者 Mei-Hua Bao Liang Tang Ji Zhou Ju Xiang Jian-Ming Li Chen-He Yi 《长沙医学院学报》 2019年第1期1-14,共14页
Community structure is a common topological property of complex networks, which attracted much attention from various fields. Optimizing quality functions for community structures is a kind of popular strategy for com... Community structure is a common topological property of complex networks, which attracted much attention from various fields. Optimizing quality functions for community structures is a kind of popular strategy for community detection, such as Modularity optimization. Here, we introduce a general definition of Modularity, by which several classical(multi-resolution) Modularity can be derived, and then propose a kind of adaptive(multi-resolution) Modularity that can combine the advantages of different Modularity. By applying the Modularity to various synthetic and real-world networks, we study the behaviors of the methods, showing the validity and advantages of the multi-resolution Modularity in community detection. The adaptive Modularity, as a kind of multi-resolution method, can naturally solve the first-type limit of Modularity and detect communities at different scales;it can quicken the disconnecting of communities and delay the breakup of communities in heterogeneous networks;and thus it is expected to generate the stable community structures in networks more effectively and have stronger tolerance against the secondtype limit of Modularity. 展开更多
关键词 Complex NETWORKS COMMUNITY detection MODULARITY MULTI-RESOLUTION
Generalized gravitomagnetic field and gravitational waves
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作者 XiaoKai He JiLiang Jing ZhouJian Cao 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第11期138-141,共4页
Synge was the first to derive the geodesic deviation entirely mathematically (1)Only later did people realize its importance [2] for describing the physical behavior of curved spacetime [3], particularly that it can u... Synge was the first to derive the geodesic deviation entirely mathematically (1)Only later did people realize its importance [2] for describing the physical behavior of curved spacetime [3], particularly that it can unambiguously manifest gravitational waves (4, 5)The geodesic deviation relates purely to the 'electric' part of a curved spacetime, while the complementary 'magnetic' part is related to the way gyroscopes adapt to geodesics. For Ricci flat spacetimes. 展开更多
关键词 GENERALIZED gravitomagnetic FIELD and GRAVITATIONAL WAVES
Research on Mobile Internet Mobile Agent System Dynamic Trust Model for Cloud Computing 预览
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作者 Weijin Jiang Yang Wang +3 位作者 Yirong Jiang Jiahui Chen Yuhui Xu Lina Tan 《中国通信:英文版》 SCIE CSCD 2019年第7期174-194,共21页
This paper analyzes the reasons for the formation of security problems in mobile agent systems, and analyzes and compares the security mechanisms and security technologies of existing mobile agent systems from the per... This paper analyzes the reasons for the formation of security problems in mobile agent systems, and analyzes and compares the security mechanisms and security technologies of existing mobile agent systems from the perspective of blocking attacks. On this basis, the host protection mobile agent protection technology is selected, and a method to enhance the security protection of mobile agents (referred to as IEOP method) is proposed. The method first encrypts the mobile agent code using the encryption function, and then encapsulates the encrypted mobile agent with the improved EOP protocol IEOP, and then traces the suspicious execution result. Experiments show that using this method can block most malicious attacks on mobile agents, and can protect the integrity and confidentiality of mobile agents, but the increment of mobile agent tour time is not large. 展开更多
关键词 MOBILE internet CLOUD COMPUTING MOBILE agent system SUBJECTIVE TRUST dynamic TRUST management
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Superposed Transparency Effect and Entanglement Generation with Hybrid System of Photonic Molecule and Dipole Emitter
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作者 袁季兵 彭朝晖 +1 位作者 唐世清 张登玉 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第3期41-44,共4页
We theoretically investigate the transparency effect with a hybrid system composed of a photonic molecule and dipole emitter. It is shown that the transparency effect incorporates both the coupled resonator-induced tr... We theoretically investigate the transparency effect with a hybrid system composed of a photonic molecule and dipole emitter. It is shown that the transparency effect incorporates both the coupled resonator-induced transparency(CRIT) effect and the dipole-induced transparency(DIT) effect. It is found that the superposed transparency windows are consistently narrower than the CRIT and DIT transparency windows. Benefiting from the superposed transparency effect, the photonic Faraday rotation effect could be realized in the photonic molecule system, which is useful for entanglement generation and quantum information processing. 展开更多
关键词 DIT TRANSPARENCY PHOTONIC MOLECULE EMITTER
Endoscopic mucosal resection of a bile duct polyp: A case report 预览
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作者 Shu Yang Li Yang +1 位作者 Xiang-Yang Wang Yu-Ming Yang 《世界临床病例杂志》 2019年第18期2864-2870,共7页
BACKGROUND Bile duct polyps are difficult to diagnose and are usually excised by open abdominal surgery or snare polypectomy using choledochoscopy via the T-tube sinus tract. However, these two resection methods requi... BACKGROUND Bile duct polyps are difficult to diagnose and are usually excised by open abdominal surgery or snare polypectomy using choledochoscopy via the T-tube sinus tract. However, these two resection methods require the surgeon to open the abdomen and cut the bile duct to place the “T” tube. Moreover, simple snare polypectomy, without submucosal injection, can only remove pedunculated polyps and not flat polyps. Therefore, a new method is required for the excision of bile duct polyps, including flat polyps. CASE SUMMARY A 63-year-old woman was hospitalized following epigastric pain lasting a month. She had a 30-year history of cholelithiasis and had undergone cholecystectomy because of cholecystolithiasis, and had undergone cholangiolithotomy twice due to choledocholithiasis. Computed tomography (CT) and magnetic resonance imaging showed a communication between the bile duct and duodenal bulb. Inside the communication, CT showed a high-density shadow which was a hypointense lesion in T2 weighted image. The lesion showed no enhancement in T1 weighted image contrast enhanced. Gastroscopy revealed an incarcerated bile duct stone in the anterior wall of the duodenal bulb, which was removed with a basket under gastroscopy. Thereafter, a choledochoduodenal fistula was revealed. Finally, a flat polyp was detected in the lower part of the common bile duct and was removed by endoscopic mucosal resection (EMR) through the fistula. To our knowledge, this is the first reported case of the removal of a bile duct polyp using EMR. CONCLUSION EMR is a safe, effective, and low-cost method for the resection of all bile duct polyps. 展开更多
关键词 Case report Cholangiolithiasis BILE DUCT POLYP ENDOSCOPIC MUCOSAL RESECTION
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Identification of microRNA transcriptome reveals that miR-100 is involved in the renewal of porcine intestinal epithelial cells
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作者 Lijun Zou Xia Xiong +4 位作者 Huansheng Yang Kexing Wang Jian Zhou Dinghong Lv Yulong Yin 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第6期816-828,共13页
MicroRNAs play important roles in various cellular processes, including differentiation, proliferation and survival. Using a pig model, this study sought to identify the miRNAs responsible for crypt-villus axis renewa... MicroRNAs play important roles in various cellular processes, including differentiation, proliferation and survival. Using a pig model, this study sought to identify the miRNAs responsible for crypt-villus axis renewal of the small intestinal epithelium.Compared to the villus upper cells, there were 15 up-regulated and 41 down-regulated miRNAs in the crypt cells of the jejunum.Notably, we found that miR-100 was expressed more in the villus upper cells than in the crypt cells, suggesting an effect on intestinal epithelium differentiation. Overexpression of miR-100 increased the activity of alkaline phosphatase, confirming that miR-100 promoted IPEC-J2 cell differentiation. MiR-100 can inhibit cell proliferation as evidenced by CCK-8 and cell cycle assay results. We also showed that miR-100 significantly inhibited the migration of IPEC-J2 cells and promoted cell apoptosis through caspase-3-dependent cleavage of Bcl-2. Furthermore, FGFR3 was identified as a potential target of miR-100 by bioinformatics analysis. We confirmed that overexpression of miR-100 suppressed FGFR3 expression in IPEC-J2 cells by directly targeting the FGFR3 3′-UTR. This is the first report of miRNAs acting on the renewal of the intestinal crypt-villus axis.Our results also showed that miR-100 promotes the differentiation and apoptosis, and inhibits the proliferation and migration of enterocytes of pigs. 展开更多
关键词 MicroRNAs SUCKLING PIGLETS crypt-villus axis cell RENEWAL IPEC-J2 cells
Sand source and formation mechanism of riverine sand dunes: a case study in Xiangshui River, China
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作者 WANG Yong YAN Ping +2 位作者 HAN Guang WU Wei ZHANG Run 《干旱区科学:英文版》 SCIE CSCD 2019年第4期525-536,共12页
Riverine sand dunes develop as a result of fluvial-aeolian interactions. The primarily barchan dune chains along the Xiangshui River(a branch of the Xar Moron River in the western part of the Horqin Sandy Land of Chin... Riverine sand dunes develop as a result of fluvial-aeolian interactions. The primarily barchan dune chains along the Xiangshui River(a branch of the Xar Moron River in the western part of the Horqin Sandy Land of China) form a typical riverine dune field. We collected a series of samples from the riverine sand dunes parallel to the direction of the prevailing wind and investigated the sand sources and formation mechanisms of these dunes by determining the grain size, heavy mineral content and optically stimulated luminescence(OSL) of the samples. The sand of the near-river dunes was coarser than the sand of the dunes distant from the river, indicating that coarse sand of the valley mainly deposited on near-river dunes. The heavy mineral analysis suggested that wind-sand activity levels were intense on the upwind dunes, but relatively weak on the downwind dunes. This indicated that the sand sources for the near-river dunes were more abundant than those of the distant dunes. Our OSL analysis of samples suggested that the deposition rates on dunes near the river were greater than the deposition rates on dunes distant from the river. The development of dunes along the river indicated that the river played an important role in dune formation and development. In addition, airflow fluctuation and the formation of the waveform dunes had a type of feedback relationship. Grain size, heavy mineral and OSL analyses are widely used methods in wind-sand research. Sand dune grain size characteristics reflect the effects of airflow on the transport and separation of sand materials, as well as the physical characteristics of the sand sources. Heavy mineral characteristics are often used to investigate the relationships between sediments and sand sources. OSL indicates dune age, revealing formation of dunes. Therefore, it is useful to explore dune sand sources, as well as the mechanisms underlying dune formation, by determining grain size, heavy mineral content and OSL. This study investigated the sand sources of riverine dunes an 展开更多
关键词 RIVERINE DUNE grain size heavy mineral optically stimulated luminescence(OSL) Horqin SANDY Land
Establishment and application of distant hybridization technology in fish
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作者 Shi Wang Chenchen Tang +11 位作者 Min Tao Qinbo Qin Chun Zhang Kaikun Luo Rurong Zhao Jing Wang Li Ren Jun Xiao Fangznou Hu Rong Zhou Wei Duan Shaojun Liu 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第1期22-45,共24页
Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated an... Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated and obtained the main rules regarding inheritance and reproduction related to fish distant hybridization. Furthermore, we established one-step and multistep breeding technologies that were suitable for interspecific hybridization and intraspecific hybridization. Simultaneously, we used these two breeding technologies to produce a batch of diploid fish lineages and tetraploid fish lineages and improved fishes. In addition, we widely discuss the methods, technologies and results of hybridization breeding, referring to the domestic and foreign literature on fish hybridization. We hope that this paper will be beneficial for the research and application of fish hybrid breeding. 展开更多
关键词 FISH DISTANT HYBRIDIZATION INTRASPECIFIC HYBRIDIZATION breeding TECHNOLOGY LINEAGE
Targeted disruption of tyrosinase causes melanin reduction in Carassius auratus cuvieri and its hybrid progeny
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作者 Qingfeng Liu Yanhua Qi +9 位作者 Qiuli Liang Jia Song Junmei Liu Wuhui Li Yuqin Shu Min Tao Chun Zhang Qinbo Qin Jing Wang Shaojun Liu 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第9期1194-1202,共9页
The white crucian carp(Carassius auratus cuvieri,WCC) not only is one of the most economically important fish in Asia,characterized by strong reproductive ability and rapid growth rates,but also represents a good germ... The white crucian carp(Carassius auratus cuvieri,WCC) not only is one of the most economically important fish in Asia,characterized by strong reproductive ability and rapid growth rates,but also represents a good germplasm to produce hybrid progenies with heterosis.Gene knockout technique provides a safe and acceptant way for fish breeding.Achieving gene knockout in WCC and its hybrid progeny will be of great importance for both genetic studies and hybridization breeding.Tyrosinase(TYR) is a key enzyme in melanin synthesis.Depletion of tyr in zebrafish and mice results in mosaic pigmentation or total albinism.Here,we successfully used CRISPR-Cas9 to target tyr in WCC and its hybrid progeny(WR) derived from the cross of WCC(♀) and red crucian carp(Carassius auratus red var.,RCC,♂).The level of TYR protein was significantly reduced in mutant WCC.Both the mutant WCC and the mutant WR showed different degrees of melanin reduction compared with the wild-type sibling control fish,resulting from different mutation efficiency ranging from 60% to 90%.In addition,the transcriptional expression profiles of a series of pivotal pigment synthesis genes,i.e.tyrp1,mitfa,mitfb,dct and sox10,were down-regulated in tyr-CRISPR WCC,which ultimately caused a reduction in melanin synthesis.These results demonstrated that tyr plays a key role in melanin synthesis in WCC and WR,and CRISPR-Cas9 is an effective tool for modifying the genome of economical fish.Furthermore,the tyr-CRISPR models could be valuable in understanding fundamental mechanisms of pigment formation in non-model fish. 展开更多
关键词 white crucian CARP HYBRIDIZATION CRISPR-Cas9 TYROSINASE PIGMENTATION
Syntheses, Structures and Herbicidal Activity of Bis(5-R-2-hydroxybenzylidene) Thiocarbohydrazide Monobutyltin Complexes [R: H(T1), Me(T2)] 预览
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作者 冯泳兰 张复兴 邝代治 《结构化学》 SCIE CAS CSCD 2019年第5期719-726,668共9页
The 1,5-disubstituted thiocarbohydrazide ligands were prepared by the condensation of thiocarbohydrazide with salicylaldehyde and 5-methylsalicylaldehyde, respectively. The butyltin complexes,[(5-R-2-hydroxy)ArCH=NNH]... The 1,5-disubstituted thiocarbohydrazide ligands were prepared by the condensation of thiocarbohydrazide with salicylaldehyde and 5-methylsalicylaldehyde, respectively. The butyltin complexes,[(5-R-2-hydroxy)ArCH=NNH]2 CS(n-BuSnCl)2, R = H(T1);R = Me(T2), based on the1,5-disubstituted thiocarbohydrazide were obtained by microwave-assisted solvothermal reaction of n-butyltintrichloride precursor with the ligands in methanol environments, which have been structurally characterized by elemental analysis, IR and(1 H, 13 C) NMR spectra. The crystals belong to monoclinic system, space groups C2/c(T1) and Pc(T2), respectively. The Sn atom is six-coordinated with distorted octahedral geometry by O, N and S atoms from ligand, C atom of butyl and two Cl atoms. In the crystal, complex T1 forms three-dimensional supramolecular assembly mediated by noncovalent interactions such as C–H···Cl and π-stacking interactions.Similarly, T2 forms an interesting two-dimensional supramolecular structure by noncovalent interactions(e.g. C–H×××Cl and N–H×××Cl) of one-dimensional band-like chain. These ligands and its butyltin complexes have growth effect on the target plants, such as Portulaca oleracea L.,Amaranthus spinosus L., Cassia tora L., Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee and Amaranthus tricolor L. The ligand L1 has a good inhibitory effect on the growth of Cassia tora L., and complex T2 has selective inhibition on the growth of Portulaca oleracea L. and Amaranthus tricolor L., which can be used as a candidate compound for Cassia tora L., Portulaca oleracea L.and Amaranthus tricolor L. herbicide. 展开更多
关键词 bis(2-hydroxybenzylidene)thiocarbohydrazide BUTYLTIN microwave SOLVOTHERMAL synthesis crystal structure herbicidal activity
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Graphene Tamm plasmon-induced giant Goos–H?nchen shift at terahertz frequencies
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作者 唐娇 许姣 +6 位作者 郑之伟 董胡 董俊 钱盛友 郭珺 蒋乐勇 项元江 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第2期29-34,共6页
In this Letter, we have shown that a giant Goos–H?nchen shift of a light beam reflected at terahertz frequencies can be achieved by using a composite structure, where monolayer graphene is coated on one-dimensional p... In this Letter, we have shown that a giant Goos–H?nchen shift of a light beam reflected at terahertz frequencies can be achieved by using a composite structure, where monolayer graphene is coated on one-dimensional photonic crystals separated by a dielectric slab. This giant Goos–H?nchen shift originates from the enhancement of the electrical field, owing to the excitation of optical Tamm states at the interface between the graphene and onedimensional photonic crystal. It is shown that the Goos–H?nchen shift in this structure can be significantly enlarged negatively and can be switched from negative to positive due to the tunability of graphene’s conductivity. Moreover, the Goos–H?nchen shift of the proposed structure is sensitive to the relaxation time of graphene and the thickness of the top layer, making this structure a good candidate for a dynamic tunable optical shift device in the terahertz regime. 展开更多
关键词 GRAPHENE Tamm plasmon-induced
Li2FeSiO4/C/Ag复合正极材料的合成与性能研究 预览
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作者 唐轶群 刘喜 +3 位作者 黄小兵 丁祥 周诗彪 陈远道 《中南大学学报:英文版》 SCIE EI CAS CSCD 2019年第6期1443-1448,共6页
Li2FeSiO4正极材料因其资源丰富、成本低、安全性能高等优点备受研究者关注,但其电导率低,倍率性能较差,极大地限制在动力和储能领域的应用。针对上述问题,本文采用固相法合成C和Ag共包覆的Li2FeSiO4,以提高其电子电导率和离子扩散系数... Li2FeSiO4正极材料因其资源丰富、成本低、安全性能高等优点备受研究者关注,但其电导率低,倍率性能较差,极大地限制在动力和储能领域的应用。针对上述问题,本文采用固相法合成C和Ag共包覆的Li2FeSiO4,以提高其电子电导率和离子扩散系数。结果表明:与Li2FeSiO4/C复合物相比,Li2FeSiO4/C/Ag复合物具有较好的电化学性能,在0.2C、5C和10C下的放电比容量分别为152、121和108 mA·h/g;1C下循环100次后,其放电容量保留为97.9%。 展开更多
关键词 锂离子电池 正极材料 硅酸亚铁锂 沥青 碳-银共包覆
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长株潭城市群地区乡村功能的动态演变及驱动机制(英文)
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作者 谭雪兰 欧阳巧玲 +3 位作者 安悦 米胜渊 蒋凌霄 周国华 《地理学报:英文版》 SCIE CSCD 2019年第8期1381-1395,共15页
As the Rural Revitalization Strategy is gradually implemented, China’s rural areas are set to have more diverse function requirements. This paper selects the Changsha-Zhuzhou-Xiangtan region(Chang-Zhu-Tan) consisting... As the Rural Revitalization Strategy is gradually implemented, China’s rural areas are set to have more diverse function requirements. This paper selects the Changsha-Zhuzhou-Xiangtan region(Chang-Zhu-Tan) consisting of 23 county-level units) as a case study and looks at its economic development, agricultural product supply, social security and ecological service functions during 1996–2016. It then constructs an index system to evaluate the temporal evolution of the region’s rural functions. SPSS 19.0 and DPS 7.05 software, as well as Pearson’s correlation coefficient analysis, system clustering, optimal segmentation of ordered samples and other methods, are used to study the evolution traits, regional differentiation characteristics and driving forces of rural functions in the region. The results show, first of all, that the overall evolution trend is increasing in functions with periodic characteristics, the key nodes being 2000 and 2008. Second, there is clear geographical differentiation in the evolution of rural functions. The economic development function shows rapid growth in the urban agglomeration’s center and relatively weak growth at the periphery;the agricultural product supply function and ecological service function are concentrated in county-level units with abundant cultivated and forest land;and the social security function displays similar geographical differentiation to the economic development function. Overall, there is an obvious discrepancy in the degree of development of rural functions among county-level units of the Changsha-Zhuzhou-Xiangtan urban agglomeration;the rural functions of the agglomeration and peripheral county-level units have different development traits;and county-level units display functional differentiation. Third, rural functions have evolved as a result of interactions between various factors, such as natural resources, socio-economic conditions and local transport conditions. The new driving forces caused by urbanization are ultimately leading the evolution 展开更多
关键词 RURAL functions SEQUENTIAL evolution regional differentiation driving FORCES RURAL REVITALIZATION Changsha-Zhuzhou-Xiangtan
Spin glassy behavior and large exchange bias effect in cubic perovskite Ba0.8Sr0.2FeO3-δ
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作者 刘宇轩 刘哲宏 +5 位作者 叶旭斌 申旭东 王潇 周博文 周光辉 龙有文 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期433-437,共5页
A single-phase iron oxideBa0.8Sr0.2FeO3-δwith a simple cubic perovskite structure in Pm-3 m symmetry is successfully synthesized by a solid-state reaction method in O2 flow. The oxygen content is determined to be abo... A single-phase iron oxideBa0.8Sr0.2FeO3-δwith a simple cubic perovskite structure in Pm-3 m symmetry is successfully synthesized by a solid-state reaction method in O2 flow. The oxygen content is determined to be about 2.81, indicating the formation of mixed Fe3+and Fe4+charge states with a disorder fashion. As a result, the compound shows small-polaron conductivity behavior, as well as spin glassy features arising from the competition between the ferromagnetic interaction and the antiferromagnetic interaction. Moreover, the competing interactions also give rise to a remarkable exchange bias effect in Ba0.8 Sr0.2 FeO2.81, providing an opportunity to use it in spin devices. 展开更多
关键词 high-pressure synthesis exchange BIAS effect SPIN GLASS
Biomimetic nanochannel membrane for cascade response of borate and cis-hydroxyl compounds: An IMP logic gate device
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作者 Meitao Deng Meng Yang +6 位作者 Yaqing Xu Yuqiong Sun Qing Wang Jianbo Liu Jin Huang Xiaohai Yang Kemin Wang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第7期1397-1400,共4页
Biomimetic nanodevice is an important branch to expand the potential applications of artificial nanochannels. Here, we constructed nanochannels for cascade response of borate and cis-hydroxyl compounds by modifying th... Biomimetic nanodevice is an important branch to expand the potential applications of artificial nanochannels. Here, we constructed nanochannels for cascade response of borate and cis-hydroxyl compounds by modifying the nanochannels of track-etched polycarbonate (TEPC) membranes with polyvinyl alcohol (PVA). Firstly, borate bound to PVA and increased the negative charge density on the surface of the nanochannels, which obstructed the transport of 1,5-naphthalene disulfonate (NDS2-). Subsequently, the addition of cis-hydroxyl compounds induced leaving of borate due to the stronger binding affinities between borate and cis-hydroxyl compounds, which reduced the negative charge density on nanochannels and then enhanced the transport of NDS2-. The cascade response of the nanochannels also accord with the properties of IMP (implication) logic gate. In addition, such nanochannels showed good reproducibility and reversibility. Therefore, this cascade response model based on nanochannels has the potential to be used as switches in area of actuators and biosensors, and is also expected to be used to understand the interaction of substances in nanoscale and simulate the physiological functions of boron. 展开更多
关键词 BIOMIMETIC NANOCHANNEL CASCADE RESPONSE Logic gate BORATE cis-Hydroxyl compound
Elastic Properties and Stacking Fault Energies of Borides,Carbides and Nitrides from First-Principles Calculations
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作者 Yong Zhang Zi-Ran Liu +4 位作者 Ding-Wang Yuan Qin Shao Jiang-Hua Chen Cui-Lan Wu Zao-Li Zhang 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第9期1099-1110,共12页
Owing to the excellent elastic properties and chemical stability,binary metal or light element borides,carbides and nitrides have been extensively applied as hard and low-compressible materials.Researchers are searchi... Owing to the excellent elastic properties and chemical stability,binary metal or light element borides,carbides and nitrides have been extensively applied as hard and low-compressible materials.Researchers are searching for harder materials all the time.Recently,the successful fabrication of nano-twinned cubic BN(Tian et al.Nature 493:385–388,2013)and diamond(Huang et al.Nature 510:250–253,2014)exhibiting superior properties than their twin-free counterparts allows an efficient way to be harder.From this point of view,the borides,carbides and nitrides may be stronger by introducing twins,whose formation tendency can be measured using stacking fault energies(SFEs).The lower the SFEs,the easier the formation of twins.In the present study,by means of first-principles calculations,we first calculated the fundamental elastic constants of forty-two borides,seventeen carbides and thirty-one nitrides,and their moduli,elastic anisotropy factors and bonding characters were accordingly derived.Then,the SFEs of the{111}<112>glide system of twenty-seven compounds with the space group F43 m or Fm3m were calculated.Based on the obtained elastic properties and SFEs,we find that(1)light element compounds usually exhibit superior elastic properties over the metal borides,carbides or nitrides;(2)the 5 d transitionmetal compounds(ReB2,WB,OsC,RuC,WC,OsN2,TaN and WN)possess comparable bulk modulus(B)with that of cBN(B=363 GPa);(3)twins may form in ZrB,HfN,PtN,VN and ZrN,since their SFEs are lower or slightly higher than that of diamond(SFE=277 mJ/m^2).Our work can be used as a valuable database to compare these compounds. 展开更多
关键词 INORGANIC compounds Elastic properties STACKING FAULT ENERGIES FIRST-PRINCIPLES calculations
Selected spherical photon orbits around a deformed Kerr black hole
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作者 ChangQing Liu ChiKun Ding JiLiang Jing 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第1期16-26,共11页
In this paper, we investigate the so-called spherical photon orbits around a deformed Kerr black hole with an extra deformation parameter. The change in the azimuth △φ and the angle of dragging of nodes per revoluti... In this paper, we investigate the so-called spherical photon orbits around a deformed Kerr black hole with an extra deformation parameter. The change in the azimuth △φ and the angle of dragging of nodes per revolution △Ω of a complete latitudinal oscillated orbit is calculated analytically. Finally, representative six examples orbits are plotted out to illustrate how spherical photon orbits look like and exhibit some interesting behavior. Especially, these spherical photon orbits are absent in circular orbits and different from the Kerr case. 展开更多
关键词 SPHERICAL PHOTON ORBITS HAMILTONIAN FORMULATION periodic latitudinal oscillation
Binary black hole systems do not interact in the Kastor-Traschen spacetime
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作者 Bing Sun ZhouJian Cao XiaoKai He 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第4期106-109,共4页
The laser-interferometer gravitational-wave observatory (LIGO) has reported several observations of binary black hole mergers. Unfortunately, no exact solutions to the equations describing binary black hole systems ex... The laser-interferometer gravitational-wave observatory (LIGO) has reported several observations of binary black hole mergers. Unfortunately, no exact solutions to the equations describing binary black hole systems exist. In particular, no exact solutions are available for the case in which a binary black hole system undergoes a merger;hence, we must rely on numerical calculations of the Maxwell-Einstein equations to construct the templates used to analyze gravitational wave data about suspected binary black hole systems [1,2]. 展开更多
关键词 LIGO black HOLE system
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