检索结果-南通市图书馆

Image Field Deformation of LAMOST due to Differential Atmospheric Refraction

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 495-502页

作者： Jin-Ling Li Bo Zhang Yong yu zhao-xiang Qi Ming zhao Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030

A vectorial expression of the image field deformation of LAMOST due to the differential atmospheric refraction is presented. The calculated results are compared with those from previous analyses based on the traditional spherical trigonometric formulas. It is demonstrated that different tangential displacements of star images during the observation tracking given by various authors are simply due to different reference points adopted. It is pointed out that the observational celestial pole is the center of the apparent diurnal motion, that, by referring to the observational celestial pole, the effect of the differential refraction on the image field of LAMOST during the 1.5-hour tracking period is approximately equivalent to a constant rotation of - 13.65″ for all declination belts. It is therefore unnecessary to design a particular tracking velocity for each observation, and this will be obviously advantageous to the observation implementation. If the maximum tracking error of the fibers is 0.2″, then the fibers are required to be able to re-position during observational tracking for sky regions south of declination ＋20° and north of declination ＋60°.

关键词： telescopes -- atmospheric effects -- methods: analytical-- methods: statistical-- astrometry

Cell Fate Switch during In Vitro Plant Organogenesis

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2008年第7期50卷 816-824页

作者： xiang yu zhao Ying Hua Su ZhiJuan Cheng Xian Sheng Zhang State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai'an 271018 China

Plant mature cells have the capability to reverse their state of differentiation and produce new organs under cultured conditions. Two phases, dedifferenUation and redifferentiation, are commonly characterized during in vitro organogenesis. In these processes, cells undergo fate switch several times regulated by both extrinsic and intrinsic factors, which are associated with reentry to the cell cycle, the balance between euchromatin and heterochromatin, reprogramming of gene expression, and so forth. This short article reviews the advances in the mechanism of organ regeneration from plant somatic cells in molecular, genomic and epigenetic aspects, aiming to provide important information on the mechanism underlying cell fate switch during in vitro plant organogenesis.

关键词： cell fate dedifferentiation plant organogenesis redifferentiation regeneration.

Plant cell totipotency: Insights into cellular reprogramming

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2021年第1期63卷 228-240页

作者： Ying Hua Su Li Ping Tang xiang yu zhao Xian Sheng Zhang State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTai'an 271018China

Plant cells have a powerful capacity in their propagation to adapt to environmental change, given that a single plant cell can give rise to a whole plant via somatic embryogenesis without the need for fertilization. The reprogramming of somatic cells into totipotent cells is a critical step in somatic embryogenesis. This process can be induced by stimuli such as plant hormones, transcriptional regulators and stress. Here, we review current knowledge on how the identity of totipotent cells is determined and the stimuli required for reprogramming of somatic cells into totipotent cells. We highlight key molecular regulators and associated networks that control cell fate transition from somatic to totipotent cells. Finally,we pose several outstanding questions that should be addressed to enhance our understanding of the mechanisms underlying plant cell totipotency.

关键词： cell reprogramming plant cell totipotency somatic embryogenesis totipotent cell

Enhancing wheat regeneration and genetic transformation through overexpression of TaLAX1

在线全文

学校读者我要写书评

暂无评论

Plant Communications 2024年第5期5卷 9-24页

作者： Yang yu Haixia yu Jing Peng Wang Jinsong Yao Yi Peng Wang Feng Li Zhang Shi Rong Wang Yajie zhao xiang yu zhao Xian Sheng Zhang Ying Hua Su State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTai’anShandong 271018China

In the realm of genetically transformed crops,the process of plant regeneration holds utmost ***,the low regeneration efficiency of several wheat varieties currently restricts the use of genetic transformation for gene functional analysis and improved crop *** research explores overex-pression of TaLAX PANICLE1(TaLAX1),which markedly enhances regeneration efficiency,thereby boost-ing genetic transformation and genome editing in *** noteworthy is the substantial increase in regeneration efficiency of common wheat varieties previously regarded as recalcitrant to genetic *** study shows that increased expression of TaGROWTH-REGULATING FACTOR(TaGRF)genes,alongside that of their co-factor,TaGRF-INTERACTING FACTOR 1(TaGIF1),enhances cytokinin accumulation and auxin response,which may play pivotal roles in the improved regeneration and transfor-mation of TaLAX1-overexpressing wheat *** of TaLAX1 homologs also significantly in-creases the regeneration efficiency of maize and soybean,suggesting that both monocot and dicot crops can benefit from this *** shed light on a gene that enhances wheat genetic trans-formation and elucidate molecular mechanisms that potentially underlie wheat regeneration.

关键词： plant regeneration genetic transformation TaLAX1 TaGRF4–TaGIF1 cytokinin auxin wheat

Recent Advances of Nanoelectrodes for Single-Cell Electroanalysis:From Extracellular, Intercellular to Intracellular

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Analysis and Testing 2022年第2期6卷 178-192页

作者： yu-Lin Liu yu-xiang zhao Ya-Bei Li zhao-Yang Ye Jun-Jie Zhang Yan Zhou Tian-Yang Gao Fei Li The Key Laboratory of Biomedical Information Engineering of Ministry of Education School of Life Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China Bioinspired Engineering and Biomechanics Center(BEBC) Xi’an Jiaotong UniversityXi’an 710049China School of Chemistry Xi’an Jiaotong UniversityXi’an 710049China

Detection at single-cell level plays a critical role in revealing cell behavior in different *** with high temporal–spatial resolution can precisely and dynamically monitor the physiological and pathological processes of various single *** field of using nanoelectrodes in single-cell electroanalysis is blooming in recent *** this review,we mainly summarize the recent advances of nanoelectrodes for single-cell electroanalysis from extracellular,intercellular to intracellular levels in the past ***,we introduce the main types of nanoelectrodes based on their geometry and characteristics for single-cell ***,the representative works of using nanoelectrodes to investigate cellular signaling biomolecules and to understand various cellular processes from the extracellular,intercellular,and intracellular levels are ***,the challenges and future prospects of nanoelectrodes for single-cell electroanalysis are *** review gives a comprehensive summary of nanoelectrodes for single-cell electroanalysis in the prospects of monitoring cell physiological topography,understanding communication mechanism and revealing physiological functions,which can provide new insights into cell-based pharmacological screening and fundamental studies of disease development mechanisms.

关键词： Nanoelectrode Single-cell electroanalysis Extracellular Intercellular Intracellular

DEK43 is a P-type pentatricopeptide repeat(PPR)protein responsible for the Cis-splicing of nad4 in maize mitochondria

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2020年第3期62卷 299-313页

作者： Ru Chang Ren Li Li Wang Lin Zhang Ya Jie zhao Jia Wen Wu Yi Ming Wei Xian Sheng Zhang xiang yu zhao State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTaian 271018China

Mitochondria, the main energy transducers in plant cells, require the proper assembly of respiratory chain complexes Ⅰ–Ⅴ for their function. The NADH dehydrogenase4(nad4) gene encodes mitochondrial respiratory chain complex Ⅰ subunit Ⅳ, but the mechanism underlying nad4 transcript splicing is unclear. Here, we report that the P-type pentatricopeptide repeat(PPR) protein DEFECTIVE KERNEL 43(DEK43) is responsible for cis-splicing of the nad4 transcript in maize. We demonstrate that DEK43 localizes to both the nucleus and mitochondria. The mutation of Dek43 resulted in embryo-lethal and light-colored defective kernels. Among the 22 mitochondrial group Ⅱ introns, the splicing efficiency of nad4 introns 1 and 3 was reduced by up to 50% compared to the wild type. The levels of complex Ⅰ and supercomplex Ⅰ+Ⅲ2 were also reduced in dek43. Furthermore, in-gel NADH dehydrogenase assays indicated that the activities of these complexes were significantly reduced in dek43. Further, the mitochondrial ultrastructure was altered in the mutant. Together, our findings indicate that DEK43, a dual-localized PPR protein,plays an important role in maintaining mitochondrial function and maize kernel development.

关键词： nad4 function. Together

AtNSF regulates leaf serration by modulating intracellular trafficking of PIN1 in Arabidopsis thaliana

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2021年第4期63卷 737-754页

作者： Li Ping Tang Yi Yang Hui Wang Lixin Li Le Liu yu Liu Jinfeng yuan xiang yu zhao Klaus Palme Ying Hua Su Xugang Li State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTai'an 271018China Sino-German Joint Research Center on Agricultural Biology College of Life SciencesShandong Agricultural UniversityTai'an 271018China Institute of Biology II/Molecular Plant Physiology Faculty of BiologyAlbert-Ludwigs-University of FreiburgSchänzlestrasse 1Freiburg D-79104Germany Key Laboratory of Saline-alkali Vegetation Ecology Restoration Ministry of EducationAlkali Soil Natural Environmental Science CenterNortheast Forestry UniversityHarbin 150040China BIOSS Centre for Biological Signalling Studies Albert-Ludwigs-University FreiburgSignalhausSchänzlestr.18Freiburg D-79104Germany Center for Biological Systems Analysis(ZBSA) Albert-Ludwigs-University FreiburgFreiburg D-79104Germany

In eukaryotes,N-ethylmaleimide-sensitive factor(NSF)is a conserved AAA+ATPase and a key component of the membrane trafficking machinery that promotes the fusion of secretory vesicles with target ***,we demonstrate that the Arabidopsis thaliana genome contains a single copy of NSF,At NSF,which plays an essential role in the regulation of leaf *** At NSF knock-down mutant,atnsf-1,exhibited more serrations in the leaf ***,polar localization of the PINFORMED1(PIN1)auxin efflux transporter was diffuse around the margins of atnsf-1 leaves and root growth was inhibited in the atnsf-1 *** PIN1-GFP accumulated in the intracellular compartments of atnsf-1 plants,suggesting that At NSF is required for intracellular trafficking of PIN between the endosome and plasma ***,the serration phenotype was suppressed in the atnsf-1 pin1-8 double mutant,suggesting that At NSF is required for PIN1-mediated polar auxin transport to regulate leaf *** CUPSHAPED COTYLEDON2(CUC2)transcription factor gene is up-regulated in atnsf-1 plants and the cuc2-3 single mutant exhibits smooth leaf margins,demonstrating that At NSF also functions in the CUC2 *** results reveal that At NSF regulates the PIN1-generated auxin maxima with a CUC2-mediated feedback loop to control leaf serration.

关键词： At NSF Auxin CUC2 leaf serration PIN1 vesicle trafficking

Expanded clinical-grade NK cells exhibit stronger effects than primary NK cells against HCMV infection

在线全文

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2023年第8期20卷 895-907页

作者： Qian-Nan Shang Xing-Xing yu Zheng-Li Xu yu-Hong Chen Ting-Ting Han yuan-yuan Zhang Meng Lv yu-Qian Sun yu Wang Lan-Ping Xu Xiao-Hui Zhang xiang-yu zhao Xiao-Jun Huang Peking University People’s Hospital Peking University Institute of HematologyNational Clinical Research Center for Hematologic DiseaseBeijing Key Laboratory of Hematopoietic Stem Cell TransplantationPeking UniversityBeijingChina Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijingChina

Cytomegalovirus (CMV) reactivation remains a common complication and leads to high mortality in patients who undergo allogeneic hematopoietic stem cell transplantation (allo-HSCT). Early natural killer (NK) cell reconstitution may protect against the development of human CMV (HCMV) infection post-HSCT. Our previous data showed that ex vivo mbIL21/4-1BBL-expanded NK cells exhibited high cytotoxicity against leukemia cells. Nevertheless, whether expanded NK cells have stronger anti-HCMV function is unknown. Herein, we compared the anti-HCMV functions of ex vivo expanded NK cells and primary NK cells. Expanded NK cells showed higher expression of activating receptors, chemokine receptors and adhesion molecules;stronger cytotoxicity against HCMV-infected fibroblasts;and better inhibition of HCMV propagation in vitro than primary NK cells. In HCMV-infected humanized mice, expanded NK cell infusion resulted in higher NK cell persistence and more effective tissue HCMV elimination than primary NK cell infusion. A clinical cohort of 20 post-HSCT patients who underwent adoptive NK cell infusion had a significantly lower cumulative incidence of HCMV infection (HR = 0.54, 95% CI = 0.32–0.93, p = 0.042) and refractory HCMV infection (HR = 0.34, 95% CI = 0.18–0.65, p = 0.009) than controls and better NK cell reconstitution on day 30 post NK cell infusion. In conclusion, expanded NK cells exhibit stronger effects than primary NK cells against HCMV infection both in vivo and in vitro.

关键词： Allogeneic haematopoietic stem cell transplantation Natural killer cells Human cytomegalovirus infection Adoptive infusion

NK cell reconstitution following unmanipulated HLA-mismatched/ haploidentical transplantation compared with matched sibling transplantation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2020年第5期63卷 781-784页

作者： Li-Juan Hu Xun-Hong Cao Xing-Xing yu Xue-Fei Liu Xiao-Su zhao Ying-Jun Chang Xiao-Hui Zhang Lan-Ping Xu yu Wang Kai-Yan Liu Xiao-Jun Huang xiang-yu zhao Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation Peking University People’s Hospital&Peking University Institute of HematologyBeijing 100044China Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation Beijing 100044China Peking-Tsinghua Center for Life Sciences Beijing 100084China

Dear Editor,NK cells are the first cells reconstituted after Allogeneic haematopoietic stem cell transplantation(allo-HSCT)(Raulet and Vance,2006;zhao et al.,2007).The roles of alloreactive NK cells are conflicting in allogeneic transplantation,mainly because several factors influence the reconstitution of NK cells,including different transplantation conditioning regimens,disease backgrounds and graft-versus-host disease(GVHD)prophylaxis(zhao et al.,2011).

关键词： al. matched transplantation