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Effects of depth-and composition-dependent thermal conductivity and the compositional viscosity ratio on the long-term evolution of large thermochemical piles of primordial material in the lower mantle of the Earth:Insights from 2-D numerical modeling

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Science China Earth Sciences 2023年第8期66卷 1865-1876页

作者： Yang LI Zhigang ZHANG Juan LI Zhidong SHI Liang ZHAO State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Science University of Chinese Academy of SciencesBeijing 100049China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Thermal conductivity plays an important role in the thermochemical evolution of Earth’s mantle.Recent mineral physics studies suggest that the thermal conductivity of the mantle varies with pressure and composition,and this may play an important role in the evolution of the Earth’s mantle.Meanwhile,the rheology of the deep mantle is also supposed to be composition-dependent.However,the dynamic influences of these factors remain not well understood.In this study,we performed numerical experiments of thermochemical mantle convection in 2-D spherical annulus geometry to systematically investigate the effects of depth-and composition-dependent thermal conductivity and the compositional viscosity ratio on the long-term evolution of the large thermochemical structure of primordial material in Earth’s mantle.Our results show that increasing the depth-dependent thermal conductivity leads to a larger core-mantle boundary(CMB)heat flow and allows the formation of more stable large thermochemical piles(e.g.,Large Low Shear Velocity Provinces,LLSVPs);while decreasing the composition-dependent thermal conductivity would slightly destabilize the primordial thermochemical piles,increase the altitude of these piles and the temperature differences between the piles and the ambient mantle.If the primordial mantle material is compositionally more viscous(e.g.,20 times than that of the ambient mantle),the long-term stability of the thermochemical piles of primordial material decreases,and this destabilizing effect will be enhanced by decreasing the composition-dependent thermal conductivity.As a result,the thermochemical piles would be unstable in the core-mantle boundary region.Therefore,our study indicates that the combined effects of depth-and composition-dependent thermal conductivity and compositional viscosity ratio are pronounced to the thermochemical evolution of the mantle.

关键词： Mantle convection Thermal conductivity Core-mantle boundary heat flow Primordial mantle material LLSVPs

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Compound soft regenerated skull material for repairing dog skull defects using bone morphogenetic protein as an inductor and nanohydroxyapatite as a scaffold

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Neural Regeneration Research 2008年第8期3卷 843-846页

作者： Zhidong SHI Mingwang Liu Zhongzong Qin Qinmei Wang Ying Guo Haiyong He Zhonghe Yu Department of Neurosurgery Third Affiliated Hospital Sun Yat-sen University Guangzhou 510630 Guangdong Province China Laboratory of Artificial Heart First Affiliated Hospital Sun Yat-sen University Guangzhou 510630 Guangdong Province China Animal Room Third Affiliated Hospital Sun Yat-sen University Guangzhou 510630 Guangdong Province China

BACKGROUND：In previous studies of skull defects and regeneration, bone morphogenetic protein as an inductor and nanohydroxyapatite as a scaffold have been cocultured with osteoblasts. OBJECTIVE： To verify the characteristics of the new skull regenerated material after compound soft regenerated skull material implantation. DESIGN, TIME AND SETTING： The self-control and inter-group control animal experiment was performed at the Sun Yat-sen University, China from February to July 2007. MATERIALS： Twenty-four healthy adult dogs of both genders weighing 15–20 kg were used in this study. Nanohydroxyapatite as a scaffold was cocultured with osteoblasts. Using demineralized canine bone matrix as a carrier, recombinant human bone morphogenetic protein-2 was employed to prepare compound soft regenerated skull material. Self-designed compound soft regenerated skull material was implanted in models of skull defects. METHODS： Animals were randomly assigned into two groups, Group A （n = 16） and Group B （n = 8）. Bilateral 2.5-cm-diameter full-thickness parietal skull defects were made in all animals. In Group A, the right side was reconstructed with calcium alginate gel, osteoblasts, and nanometer bone meal composite; the left side was reconstructed with calcium alginate gel, osteoblasts, nanometer bone meal and recombinant human bone morphogenetic protein-2 composite. In Group B, the right side was kept as a simple skull defect, and the left side was reconstructed with calcium alginate gel, osteoblasts, nanometer bone meal and recombinant human bone morphogenetic protein-2 composite. MAIN OUTCOME MEASURES： Bone regeneration and histopathological changes at the site of the skull defect were observed with an optical microscope and a scanning electron microscope after surgery. The ability to form bone was measured by alizarin red S staining. In vitro cultured osteoblasts were observed for morphology. RESULTS： One month following surgery, newly formed bone trabeculae mostly covered the broken ends of the fractured bone and grew to

关键词： tissue engineering skull regeneration animal experiment

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Magic angles and flat Chern bands in alternating-twist multilayer graphene system

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Journal of Materials Science & Technology 2022年第16期111卷 28-34页

作者： Zhiyong Liu Wenyuan shi Teng Yang zhidong Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Western Reserve Academy 115 College Street HudsonOhio 44236United States

Based on the effective continuum model,we study alternating-twist multilayer graphene system and emergence of magic angles and flat band topology.All the alternating-twist multilayer graphene system(from triple layers to few layers)are found to have flat bands at magic angles where the area of AA stacking equals n-fold(n is an integer)electron cyclotron area.From the pseudo-Landau-level representation,there is always an isolated Dirac band in the alternating-twist graphene system constructed by odd number of layers.Since each pair of flat bands can be perceived as the zeroth pseudo-Landau-levels in two dimensional Dirac fermions,electron in the flat band pair can feel a pseudo-magnetic field with the same magnitude but the opposite sign.Calculated Chern number for each flat band is+1(or-1)which can be tuned by twisting in the vicinity of magic angles or by gating.The concurrent appearance of strong correlation and band topology of flat bands in the alternating-twist multilayer graphene may pave an avenue for the new understanding of superconductivity observed in triple-layered graphene,and supply a new playground for realizing(quantum)anomalous Hall effect.

关键词： Alternating-twist multilayer graphene Magic angle Flat band Band topology

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Application of a venous conduit as a stent for repairing rabbit facial nerve injury

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Neural Regeneration Research 2007年第12期2卷 717-721页

作者： Zhidong SHI Mingwang Liu Zhongzong Qin Qinmei Wang Ying Guo Zhuopeng Ye Zhonghe Yu Department of Neurosurgery Third Hospital Affiliated to Sun Yat-sen University Guangzhou 510630 Guangdong Province China Laboratory for Artificial Heart First Hospital Affiliated to Sun Yat-sen University Guangzhou 510089 Guangdong Province China Animal Laboratory Third Hospital Affiliated to Sun Yat-sen University Guangzhou 510630 Guangdong Province China

BACKGROUND： Recently, many investigators have tried to use natural biomaterials, such as, artery, vein, decalcified bone, etc., as conduits for nerve repair. However, immunological rejection of conduits made of natural biomaterials limits their application. Therefore, it is essential to identify more suitable types of biomaterials. OBJECTIVE： To observe the characteristics of a bioengineering processing method using venous conduit as a stent for repairing facial nerve injury. DESIGN： A controlled observational experiment. SETTING： Animal Laboratories of the Third Hospital Affiliated to Sun Yat-sen University and the 157 Hospital. MATERIALS： Thirty-three male New Zealand rabbits of pure breed, weighing 1.5 to 2.0 kg, were provided by Medical Experimental Animal Room of Sun Yat-sen University. The protocol was carried out in accordance with animal ethics guidelines for the use and care of animals. Venous conduits and autogenous nerves were transplanted into the left and right cheeks, respectively. Eleven animals were chosen for anatomical observations at 5, 10 and 15 weeks after surgery. METHODS： This experiment was carried out in the Animal Laboratories of the Third Hospital Affdiated to Sun Yat-sen University and the 157 Hospital between May and November 2006. After animals were anesthetized, 15 mm of retromandibular vein was harvested for preparing a venous conduit. Approximately 3 cm of low buccal branch of facial nerve was exposed. A segment of 1.2 cm nerve was resected from the middle, and a gap of 1.5 cm formed due to bilateral retraction. The prepared venous conduit of 1.5 cm was sutured to the outer membrane of the severed ends of the nerve. Muscle and skin were sutured layer by layer. Using the same above-mentioned method, the low buccal branch of right autogenous facial nerve was resected, and the left facial nerve segment from the same animal was transplanted using end-to-end neurorrhaphy for control. MAIN OUTCOME MEASURES：（1）Post-operatively, food intake, vibrissae activity and wound heali

关键词： bioengineering venous conduit repair facial nerve injury

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白云石晶体结构和地球化学特征对沉积环境响应:以扬子地台晚埃迪卡拉纪灯影组白云岩为例

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地学前缘 2024年第3期31卷 68-79页

作者：杨志波季汉成鲍志东史燕青赵雅静向鹏飞中国石油大学(北京)地球科学学院北京102249 中国石油大学(北京)油气资源与探测国家重点实验室北京102249

受沉积环境的影响,在白云石形成过程中,其晶体结构与地球化学记录着相应的环境信息。本文以扬子地台晚埃迪卡拉纪灯影组杨坝剖面为例,通过系统采样研究了白云石的晶体结构和地球化学特征,明晰了基于岩石学和地球化学特征的灯影组沉积环... 详细信息

受沉积环境的影响,在白云石形成过程中,其晶体结构与地球化学记录着相应的环境信息。本文以扬子地台晚埃迪卡拉纪灯影组杨坝剖面为例,通过系统采样研究了白云石的晶体结构和地球化学特征,明晰了基于岩石学和地球化学特征的灯影组沉积环境演化,归纳出了白云石晶体结构、地球化学特征与形成环境的耦合关系。结果表明:(1)杨坝剖面灯影组主要发育叠层石、核形石、泡沫棉石及凝块石等4种微生物白云岩和少量的晶粒、颗粒及角砾白云岩,垂向发育多期的微生物白云岩叠置韵律层,主要为局限台地潮坪相颗粒滩相。(2)地球化学分析表明,灯影组沉积演化过程为:一段主要为干旱气候、较高盐度的较浅水体,发育泥、粉晶白云岩沉积;二段下部水体加深、潮湿、低盐度,微生物白云岩最为发育;二段中上部水体总体相对较浅,湿度降低,盐度略增高;四段时水体先加深后迅速变浅,湿度逐渐降低,盐度亦逐渐增大。(3)研究区白云石晶体结构特征突显出典型的高Mg/Ca环境下流体参与形成,在干旱、高盐度的环境下,a/c值负偏,潮湿、低盐度的环境会导致晶胞参数a/c值正偏。有序度分布表明,随有序度的增加,a/c值逐渐靠近理想白云石。该结果不仅阐明准同生白云石晶体结构与形成环境关联,还揭示元古宇灯影组古海水环境特征。

关键词：晶体结构地球化学特征沉积环境扬子地台灯影组

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气单胞菌属低温淀粉酶基因改造与原核表达

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新疆农业科学 2024年第2期61卷 479-484页

作者：楚敏史应武顾美英杨红梅霍向东张志东新疆农业科学院微生物应用研究所/新疆特殊环境微生物实验室乌鲁木齐830091

【目的】获取低温淀粉酶基因,分析其相关功能,为工业生产上的应用提供参考。【方法】以气单胞菌(Aeromonas)LA77为出发菌株克隆低温α-淀粉酶基因,以BL-21(DE3)为宿主菌进行克隆。分析其它已知气单胞菌属低温α-淀粉酶基因同源性,设计... 详细信息

【目的】获取低温淀粉酶基因,分析其相关功能,为工业生产上的应用提供参考。【方法】以气单胞菌(Aeromonas)LA77为出发菌株克隆低温α-淀粉酶基因,以BL-21(DE3)为宿主菌进行克隆。分析其它已知气单胞菌属低温α-淀粉酶基因同源性,设计特异引物,PCR扩增获得C13片段,将其克隆到pMAL-2X,转化到BL-21(DE3)中,筛选蓝白斑,验证PCR及EcoRⅠ和HindⅢ的双酶切,获得高效表达生物工程菌株pMAL-2X-C13。设计定点突变引物,以pMAL-2X-C13为模板,获得低温淀粉酶基因突变株三株C19、C29、C43。【结果】表达蛋白的分子大小为114kD,突变菌株C19蛋白表达量均高于pMAL-2X-C13。【结论】低温淀粉酶基因突变株C19比原始菌株pMAL-2X-C13淀粉酶基因蛋白表达量更高。

关键词：气单胞菌属 α-低温淀粉酶基因改造原核表达

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DSEMR: A database for special environment microorganisms resource and associating them with synthetic biological parts

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Synthetic and Systems Biotechnology 2023年第4期8卷 647-653页

作者： Yuzhou Wang Jinyi Qian Fang Yan Yuetong Wang Tianqiong shi zhidong Zhang Chao Ye He Huang School of Food Science and Pharmaceutical Engineering Nanjing Normal UniversityNanjing210023China Institute of Microbiology Xinjiang Academy of Agricultural SciencesUrumqi830091China

Special environmental microorganisms are considered to be of great industrial application value because of their special genotypes,physiological functions and metabolites.The research and development of special environmental microorganisms will certainly bring about some innovations in biotechnology processes and change the face of bioengineering.The Special Environmental Microbial Database(DSEMR)is a comprehensive database that provides information on special environmental microbial resources and correlates them with synthetic biological parts.DSEMR aggregates information on specific environmental microbial genomes,physiological properties,culture media,biological parts,and metabolic pathways,and provides online tool analysis data,including 5268 strains from 620 genera,31 media,and 42,126 biological parts.In short,DSEMR will become an important resource for the study of microorganisms in special environments and actively promote the development of synthetic biology.

关键词： Special environment microorganism Physiological functions Synthetic biological parts

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Synthesis and characterization of (Ni,Sb)-co-doped rutile ceramic pigment via mechanical activation-assisted solid-state reaction

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Particuology 2018年第6期16卷 20-29页

作者： shi Zhang zhidong Pan Yanmin Wang School of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China

(Ni,Sb)-co-doped rutile yellow ceramic pigments were synthesized via a mechanical activation-assisted solid-state reaction in a stirred bead mill.The effects of mechanical grinding of the raw materials on the synthesis of (Ni,Sb)-co-doped rutile pigment were investigated.The results show that mechanical activation effectively decreased the crystallinity of the mixed precursors,thus enhancing their reactivity and the migration rate of ions.These effects lowered the temperature required for formation of the rutile phase.Compared with results from a mixture of separately ground precursors,the mixture of raw materials ground together was more effective for accelerating nickel/antimony ions doping into the TiO2structure and improved the color performance of the pigment.The pigment from the mixed raw materials ground for 2.0h and heat-treated at 1100℃ could be used as an environmentally-friendly ceramic yellow pigment owing to its low-toxicity,bright yellow hue,good chemical/thermal durability, and high cost-effectiveness.

关键词： Mechanical activation Solid-state synthesis (Ni,Sb)-co-doped rutile Ceramic pigment

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甘南牦牛(Bos grunniens)FBXO32基因突变及其与胴体和肉质性状关联分析

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基因组学与应用生物学 2024年第3期43卷 465-477页

作者：周瑞锋石斌刚王向彦祁有鹏何兆华朱春娥张雪萍白彦斌赵志东胡江甘肃农业大学动物科学技术学院甘肃省草食动物生物技术重点实验室甘肃省牛羊基因改良工程实验室兰州730070

为了分析甘南牦牛(Bos grunniens)肌肉萎缩盒蛋白32(F-box protein 32,FBXO32)基因的单核苷酸多态性(single nucleotide polymorphism,SNP)位点,以及基因型与胴体和肉质性状间的相关性,本研究以593头甘南牦牛为研究对象,采用混池测序和... 详细信息

为了分析甘南牦牛(Bos grunniens)肌肉萎缩盒蛋白32(F-box protein 32,FBXO32)基因的单核苷酸多态性(single nucleotide polymorphism,SNP)位点,以及基因型与胴体和肉质性状间的相关性,本研究以593头甘南牦牛为研究对象,采用混池测序和竞争性等位基因特异性PCR(kompetitive allele specific PCR,KASP)技术,检测了甘南牦牛FBXO32基因突变位点及基因型,分析了基因型与甘南牦牛胴体及肉质性状的相关性。结果表明,从甘南牦牛FBXO32基因检测到7个SNP位点,分别是位于5′UTR区的SNP1(g.267A>C)、外显子1区的SNP2(g.326G>T)、外显子8区的SNP3(g.31231G>C),以及3′UTR区的SNP4(g.31352G>A)、SNP5(g.31424C>T)、SNP6(g.31503A>C)和SNP7(g.31504A>G)。其中,SNP1、SNP4、SNP5、SNP6与肌肉嫩度显著相关(P<0.05),SNP3、SNP6、SNP7与失水率显著相关(P<0.05),SNP1、SNP2、SNP3、SNP4、SNP5、SNP7与眼肌面积显著相关(P<0.05),SNP2、SNP5、SNP6与胴体重显著相关(P<0.05)。7个SNP位点构建的9种有效单倍型组合中,单倍型组合H2H2的个体肌肉嫩度小、熟肉率高,单倍型组合H1H2的个体熟肉率高、眼肌面积大、失水率低。FBXO32基因突变位点可作为甘南牦牛胴体及肉质性状潜在分子遗传标记,研究结果丰富了甘南牦牛经济性状分子遗传理论基础。

关键词：甘南牦牛(Bos grunniens) FBXO32基因胴体性状肉质性状单倍型

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Change of Cytokines in Chronic Hepatitis B Patients and HBeAg are Positively Correlated with HBV RNA, Based on Real-world Study

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Journal of Clinical and Translational Hepatology 2022年第3期10卷 390-397页

作者： Qiqi Zhang Hui Huang Aijun Sun Chunyan Liu zhidong Wang Feifan shi Wei Duan Xueying Sun Qi Wang Ping Sun Chunwen Pu Yong Zhang Department of Biobank The Sixth Affiliated People’s Hospital of Dalian Medical UniversityDalianLiaoningChina Outpatient Department of Hepatitis The Sixth Affiliated People’s Hospital of Dalian Medical UniversityDalianLiaoningChina Department of Pathology The Sixth Affiliated People’s Hospital of Dalian Medical UniversityDalianLiaoningChina School of Pharmacy Shenyang Pharmaceutical UniversityShenyangLiaoningChina School of Medicine Deakin UniversityVictoriaAustralia

Background and Aims:The natural course of chronic hepatitis B virus(HBV)infection is widely studied;however,follow-up studies of the same patients are scanty.Here,we studied the dynamic changes of serum HBV RNA and cytokines in hepatitis B virus e antigen(HBeAg)-positive patients treated with entecavir(ETV)to explore the relationship between the HBV serum viral nucleic acids and host immunity.Methods:Thirty-three chronic hepatitis B patients who are HBeAg-positive,with high virus load(HBV DNA>20,000 IU/mL),and received standard nucleos(t)ide analogue(NA)antiviral therapy(ETV)for more than 48 weeks were included.The serum levels of HBV nucleic acids and selected cytokines were measured at 0,12,24,and 48 weeks respectively.Results:Serum HBV RNA could still be detected while serum HBV DNA had fallen below the detection limit in patients treated with ETV.There was a strong positive correlation between HBV RNA and HBeAg,with a concomitant decrease in the secretion of cytokines from type 1 helper T(Th1)/type 2 helper T(Th2)/interleukin(IL)-17 producing T(Th17)cells.IL-4 and IL-10 were the main cytokines negatively associated with serum HBV RNA.Conclusions:HBeAg can be used to reflect the load of HBV RNA indirectly,because serum HBV RNA has not been widely used in clinical practice.Meanwhile,serum IL-4 and IL-10 might be explored in combination with HBV RNA in guiding future clinical antiviral therapy.

关键词： HBV RNA Cytokines HBeAg positive Entecavir Chronic hepatitis B

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