检索结果-南通市图书馆

Reevaluation by the CRISPR/Cas9 knockout approach revealed that multiple pluripotency-associated lncR NAs are dispensable for pluripotency maintenance while Snora73a/b is essential for pluripotency exit

引用

Science China Life sciences 2024年

作者： Zhen Li Xuefei Li Jingxia Lin Yangming Wang Huiqing Cao Jiajian Zhou Institute of Molecular Medicine College of Future Technology Peking University Dermatology Hospital Southern Medical University Beijing Advanced Center of RNA Biology (BEACON) Peking University

Many long noncoding RNAs(lncRNAs) have been identified through siRNA-based screening as essential regulators of embryonic stem cell(ESC) pluripotency. However, the biological and molecular functions of most lncRNAs remain unclear. Here, we employed CRISPR/Cas9-mediated knockout technology to explore the functions of 8 lncRNAs previously reported to promote pluripotency in mouse ESCs. Unexpectedly, all of these lncRNAs were dispensable for pluripotency maintenance and proliferation in mouse ESCs when disrupted individually or in combination. Single-cell transcriptomic analysis also showed that the knockout of these lncRNAs has a minimal impact on pluripotency gene expression and cell identity. We further showed that several small hairpin RNAs(shRNAs) previously used to knock down lncRNAs caused the downregulation of pluripotency genes in the corresponding lncRNA-knockout ESCs, indicating that off-target effects likely responsible for the pluripotency defects caused by these shRNAs. Interestingly, linc1343-knockout and linc1343-knockdown ESCs failed to form cystic structures and exhibited high expression of pluripotency genes during embryoid body(EB) differentiation. By reintroducing RNA products generated from the linc1343 locus, we found that two snoRNAs, Snora73a and Snora73b, but not lncRNAs, could rescue pluripotency silencing defects during EB differentiation of linc1343 knockout ESCs. Our results suggest that the 8 previously annotated pluripotency-regulating lncRNAs have no overt functions in conventional ESC culture; however, we identified snoRNA products derived from an annotated lncRNA locus as essential regulators for silencing pluripotency genes.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Evaluating the effectiveness of marine actinobacterial extract and its mediated titanium dioxide nanoparticles in the degradation of azo dyes

引用

Journal of Environmental sciences 2014年第4期26卷 775-782页

作者： S Priyaragini S Veena D Swetha L Karthik G Kumar K V Bhaskara Rao Molecular and Microbiology Research Laboratory Environmental Biotechnology Division School of Bio Sciences and Technology VIT University

Aim of the present study was to synthesize titanium dioxide nanoparticles （YiO2 NPs） from marine actinobacteria and to develop an eco-friendly azo-dye degradation method. A total of five actinobacterial isolates were isolated from Chennai marine sediments, Tamilnadu, India and analyzed for the synthesis of TiO2 NPs using titanium hydroxide. Among these, the isolate PSV 3 showed positive results for the synthesis of TiO2 NPs, which was confirmed by UV analysis. Further characterization of the synthesized TiO2 NPs was done using XRD, AFM and FI＇-IR analysis. Actinobacterial crude extract and synthesized TiO2 NPs was found efficient in degrading azo dye such as Acid Red 79 （AR-79） and Acid Red 80 （AR-80）. Degradation percentage was found to be 81% for AR-79, 83% for AR-80 using actinobacterial crude extract and 84% for AR-79, 85% for AR-80 using TiO2 NPs. Immobilized actinobacterial ceils showed 88% for AR-79 and 81% for AR- 80, dye degrading capacity. Degraded components were characterized by FT-IR and GC-MS analysis. The phytotoxicity test with 500 μg/mL of untreated dye showed remarkable phenotypic as well as cellular damage to Tagetes erecta plant. Comparatively no such damage was observed on plants by degraded dye components. In biotoxicity assay, treated dyes showed less toxic effect as compared to the untreated dyes.

关键词： actinobacteria azo dye degradation ZiO2 NPs biotoxicity Tagetes erecta

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Global optimization of double protograph LDPC codes for JSCC scheme

引用

Science China(Information sciences) 2024年第6期67卷 455-456页

作者： Qiwang CHEN Chen CHEN Yu-Cheng HE Zhiping XU Xiamen Key Laboratory of Mobile Multimedia Communications College of Information Science and EngineeringHuaqiao University Key Laboratory of Underwater Acoustic Communication and Marine Information technology (Xiamen University) Ministry of Education School of Ocean Information Engineering Jimei University

A double low-density parity-check (D-LDPC) coding system was proposed in[1]as a typical joint source-channel coding(JSCC) scheme[1–5].In this system,two LDPC coding matrices perform source and channel coding,respectively.An important concept in a D-LDPC coding system is the introduction of a linking matrix between the check nodes (CNs)of the source coding matrix and the variable nodes (VNs) of the channel LDPC coding matrix.

关键词： JOINT SOURCE DESIGN

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Integrated Test System for Large-aperture Telescopes Based on Astrophotonics Interconnections

引用

Instrumentation 2024年第1期11卷 1-9页

作者： Qichang An Kun Wang Xinyue Liu Hongwen Li Jiakang Zhu Changchun Institute of Optical Precision Machinery and Physics Chinese Academy of SciencesChangchunJilin 130033China University of Chinese Academy of sciences Beijing 100039China Jilin Key Laboratory of Intelligent Wavefront Sensing and Control ChangchunJilin 130033China

This study aims to improve the integrated testing of large-aperture telescopes to clarify the fundamental principles of an integrated testing system based on astrophotonics.Our demonstration and analyses focused on element-position sensing and modulation based on spatial near-geometric beams,high-throughput step-difference measurements based on channel spectroscopy,distributed broadband-transmittance testing,and standard spectral tests based on near-field energy regulation.Comprehensive analyses and experiments were conducted to confirm the feasibility of the proposed system in the integrated testing process of large-aperture telescopes.The results demonstrated that the angular resolution of the light rays exceeded 5arcsec,which satisfies the requirements for component-position detection in future large-aperture telescopes.The measurement resolution of the wavefront tilt was better than 0.45μrad.Based on the channel spectral method—which combined a high signal-to-noise ratio and high sensitivity,along with continuous-spectral digital segmentation and narrowband-spectral physical segmentation—a resolution of 0.050μm and a range of 50μm were obtained.After calibration,the measurement resolution of the pupil deviation improved to exceed 4%accuracy,and the transmission measurements achieved a consistency of over 2%accuracy.Regarding fringe-broadband interferometry measurements,the system maintained high stability,ensuring its operation within the coherence length,and robustly detected the energy without unwrapping the phase.The use of a projector for calibrating broadband-spectrum measurements led to a reduction in contrast from 0.8142 to 0.6038,which further validates the system's applicability in the integrated testing process of large-aperture telescopes.This study greatly enhanced the observational capabilities of large-aperture telescopes while reducing the integrated system's volume,weight,and power consumption.

关键词： curvature sensing wavefront aberration astrophotonics large-aperture telescope

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Studies on biodiversity and bioprospecting of active mud volcano associated bacteria and actinobacteria from Baratang,Andaman Islands,India

引用

Systems Microbiology and Biomanufacturing 2023年第2期3卷 339-357页

作者： Balakrishnan Meena Lawrance Anburajan Karankal Aryamol Nambali Valsalan Vinithkumar Gopal Dharani Atal Centre for Ocean Science and technology for Islands National Institute of Ocean TechnologyMinistry of Earth SciencesGovernment of IndiaDollygunjPort BlairAndaman and Nicobar Islands 744103India Marine Biotechnology division Ocean Science and Technology for Islands GroupNational Institute of Ocean TechnologyMinistry of Earth SciencesGovernment of IndiaChennaiTamil Nadu 600100India Department of Marine Biology Kerala University of Fisheries and Ocean StudiesKochiKerala 682506India

A total of 79 bacteria and 101 actinobacteria strains were isolated from the sediment samples of the different points of Baratang mud volcano viz.,point of the eruption(M),middle of the volcano(MD),and the dried part of the mud volcano(E).Based on the biochemical and molecular characterization,the isolates were categorized under the phyla Proteobacteria,Firmicutes and Proteobacteria included representatives of Classes Alphaproteobacteria,Gammaproteobacteria and Deltaproteobacteria of 29 genera with 38 distinct ribotypes.Thirty-eight bacterial strains from four different regions of mud volcano revealed excellent activity for indole-3-acetic acid(IAA)production.Excellent antagonistic property,plant growth promoting properties such as IAA production,phosphate,potassium and zinc solubilization were identified in Bacillus megaterium NIOT_MV 31 strain of 38 studied isolates.In this study,we investigated the optimization of IAA production by B.megaterium NIOT_MV 31 and its formulation as a plant growth promoter to improve economic and agricultural development.Maximum IAA yield was achieved using optimal conditions(42.63 mg/mL)in the presence of optimized tryptophan after 4 days of incubation.Twofold increase in the plant growth parameters were observed to that of control plants.Optimization of culture conditions resulted in a fourfold increase in IAA production by B.megaterium NIOT_MV 31 cells.The results clearly demonstrated that,B.megaterium NIOT_MV 31 holds great potential as a source for IAA production and may be useful for commercial applications.

关键词： Mud volcano Plant growth promoter Indole-3-acetic acid Seed germination Bacillus megaterium

来源：

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

通过镧掺杂调控提升电子缺陷型CoO的硝酸盐电还原制氨效率(英文)

引用

Science China Materials 2024年

作者：何勋谢婷董凯南爵孙航姚永超范晓娅郑冬冬罗永嵩孙圣钧刘倩李露明储伟谢丽思孔清泉孙旭平 Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of China College of Chemistry Chemical Engineering and Materials Science Shandong Normal University Department of Science and Environmental Studies Faculty of Liberal Arts and Social Science The Education University of Hong Kong Institute for Advanced Study Chengdu University

电催化还原硝酸盐(NO3-)能有效转化NO3-为氨(NH3),实现废水中NO3-污染物的去除和NH3的生产.在本研究中,我们采用稀土元素镧掺杂的Co3O4纳米线阵列生长在碳布上(La-Co3O4/CC)作为高效的电催化剂,实现了NO3-向NH3的转化.La-Co3O4/CC展示...

电催化还原硝酸盐(NO3-)能有效转化NO3-为氨(NH3),实现废水中NO3-污染物的去除和NH3的生产.在本研究中,我们采用稀土元素镧掺杂的Co3O4纳米线阵列生长在碳布上(La-Co3O4/CC)作为高效的电催化剂,实现了NO3-向NH3的转化.La-Co3O4/CC展示了高的NH3法拉第效率(96.36%)和NH3产率(537.44μmol h-1cm-2),明显优于Co3O4(87.78%,279.4μmol h-1cm-2).理论计算表明,La掺杂促进了NO3-的吸附并优化了氢化过程,从而提高了Co3O4在NO3-转换和NH3选择性方面的电还原活性.此外,以La-Co3O4/CC组装的Zn-NO3-电池实现了9.86 mW cm-2的峰值功率密度.本项工作推动了基于Co3O4的电极在电催化领域的应用,并突显了稀土元素掺杂在NO3-还原反应中的有效性.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Are cyclones in Jupiter's polar regions modulated by the radially directional Rayleigh–Taylor instability?

引用

Earth and Planetary Physics 2023年第2期7卷 229-236页

作者： ChuXin Chen Chinese Academy of sciences Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesSchool of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

The persistence and symmetry of cyclones around the poles of Jupiter are unknown.In the present investigation,inspired by cyclones at the South Pole of the Earth,we propose a mechanism that provides an explanation for this problem.The negative temperature gradient with respect to latitude may play an important role here.This temperature gradient is induced by solar radiation because of the small axial inclination of Jupiter.Our numerical simulations suggest that cyclones in the polar regions of Jupiter may be modulated or controlled by the radially directional Rayleigh–Taylor instability,driven by centrifugal force and the negative temperature gradient along the latitude.

关键词： cyclone polar region of Jupiter temperature gradient along the latitude Rayleigh–Taylor instability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Radiation Principle and Spatial Direct Modulation Method of a Low Frequency Antenna Based on Rotating Permanent Magnet

引用

Chinese Journal of Electronics 2022年第4期31卷 674-682页

作者： LIU Wenyi ZHANG Feng SUN Faxiao GONG Zhaoqian LIU Xiaojun FANG guangyou Aerospace Information Research Institute Chinese Academy of Sciences Key laboratory of Electromagnetic Radiation and Sensing technology University of Chinese Academy of sciences

The theory of mechanical antenna is still in its infancy at present, and its radiation mechanism,field distribution, modulation methods and other basic theories need to be explored and improved. The radiation mechanism of a rotating-magnet based mechanical antenna(RMBMA) is explored. An equivalent radiation model of the mechanical antenna is established. The field formula of mechanical antenna is derived using this model and rotation matrix. The spatial direct modulation method of mechanical antenna is also investigated. Two prototype antennas are fabricated using DC/AC servo motors and Nd Fe B magnets, and experiments are carried out to verify the correctness of the derivation and analysis. The measured and simulated results are in consistent with each other. By precisely controlling the moving parameters of an AC servo motor, signal of binary amplitude shift keying(BASK) is generated, and the original code sequence is recovered by demodulation.

关键词： Mechanical antenna Rotating permanent magnet Rotation matrix Spatial direct modulation

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Metabolic utilization of intravenously injected iron from different iron sources in target tissues of broiler chickens

引用

Animal Nutrition 2022年第2期9卷 74-83页

作者： Lin Lu Xueyu Dong Xuelian Ma Liyang Zhang Sufen Li Xugang Luo Xiudong Liao Mineral Nutrition Research division State Key Laboratory of Animal NutritionInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing100193China Poultry Mineral Nutrition Laboratory College of Animal Science and TechnologyYangzhou UniversityYangzhou225000China Department of Animal Science Hebei Normal University of Science and TechnologyQinhuangdao066004China

No information is available regarding the utilization of iron (Fe) from different Fe sources at a targettissue level. To detect differences in Fe metabolic utilization among Fe sources, the effect of intravenouslyinjected Fe on growth performance, hematological indices, tissue Fe concentrations and Fe-containingenzyme activities and gene expressions of Fe-containing enzymes or protein in broilers was investigated.On d 22 post-hatching, a total of 432 male chickens were randomly allotted to 1 of 9 treatments ina completely randomized design. Chickens were injected with either a 0.9% (wt/vol) NaCl solution(control) or a 0.9% NaCl solution supplemented with Fe sulphate or 1 of 3 organic Fe sources. The 3organic Fe sources were Fe chelates with weak (Fe-MetW), moderate (Fe-ProtM) or extremely strong (Fe-ProtES) chelation strength. The 2 Fe dosages were calculated according to the Fe absorbabilities of 10%and 20% every 2 d for a duration of 20 d. Iron injection did not affect (P > 0.05) ADFI, ADG or FCR duringeither 1 to 10 d or 11 to 20 d after injections. Hematocrit and Fe concentrations in the liver and kidney ond 10 after Fe injections, and Fe concentrations in the liver or pancreas and ferritin heavy-chain (FTH1)protein expression level in the liver or spleen on d 20 after Fe injections increased (P≤0.05) as injectedFe dosages increased. When the injected Fe level was high at 20% Fe absorbability, the chickens injectedwith Fe-ProtES had lower (P < 0.001) liver or kidney Fe concentrations and spleen FTH1 protein levelsthan those injected with Fe-MetW or Fe-ProtM on d 20 after injections. And they had lower (P < 0.05)liver cytochrome C oxidase mRNA levels on d 20 after injections than those injected with Fe-MetW or Fesulphate. The results from this study indicate that intravenously injected Fe from Fe-ProtES was the least utilizable and functioned in the sensitive target tissue less effectively than Fe from Fe sulfate, Fe-MetW or Fe-ProtM.

关键词： Intravenous injection Iron-containing protein Gene expression Iron source Broiler

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Sphingosine 1-phosphate receptor 1 regulates bloodbrain barrier permeability in epileptic mice

引用

Neural Regeneration Research 2023年第8期18卷 1763-1769页

作者： Li-Xiang Yang Yuan-Yuan Yao Jiu-Rong Yang Hui-Lin Cheng Xin-Jian Zhu Zhi-Jun Zhang Department of Neurosurgery Zhongda HospitalSchool of MedicineSoutheast UniversityNanjingJiangsu ProvinceChina Department of Pharmacology Medical School of Southeast UniversityNanjingJiangsu ProvinceChina Department of Neurology Zhongda HospitalSchool of MedicineInstitution of NeuropsychiatryKey Laboratory of Developmental Genes and Human DiseaseSoutheast UniversityNanjingJiangsu ProvinceChina Department of Mental health and Public health Faculty of Life and Health SciencesShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Destruction of the blood-brain barrier is a critical component of epilepsy pathology.Several studies have demonstrated that sphingosine 1-phosphate receptor 1 contributes to the modulation of vascular integrity.However,its effect on blood-brain barrier permeability in epileptic mice remains unclear.In this study,we prepared pilocarpine-induced status epilepticus models and pentylenetetrazol-induced epilepsy models in C57BL/6 mice.S1P1 expression was increased in the hippocampus after status epilepticus,whereas tight junction protein expression was decreased in epileptic mice compared with controls.Intraperitoneal injection of SEW2871,a specific agonist of sphingosine-1-phosphate receptor 1,decreased the level of tight junction protein in the hippocampus of epileptic mice,increased blood-brain barrier leakage,and aggravated the severity of seizures compared with the control.W146,a specific antagonist of sphingosine-1-phosphate receptor 1,increased the level of tight junction protein,attenuated blood-brain barrier disruption,and reduced seizure severity compared with the control.Furthermore,sphingosine 1-phosphate receptor 1 promoted the generation of interleukin-1βand tumor necrosis factor-αand caused astrocytosis.Disruption of tight junction protein and blood-brain barrier integrity by sphingosine 1-phosphate receptor 1 was reversed by minocycline,a neuroinflammation inhibitor.Behavioral tests revealed that sphingosine 1-phosphate receptor 1 exacerbated epilepsy-associated depression-like behaviors.Additionally,specific knockdown of astrocytic S1P1 inhibited neuroinflammatory responses and attenuated blood-brain barrier leakage,seizure severity,and epilepsy-associated depression-like behaviors.Taken together,our results suggest that astrocytic sphingosine 1-phosphate receptor 1 exacerbates blood-brain barrier disruption in the epileptic brain by promoting neuroinflammation.

关键词： adeno-associated virus astrocytes blood-brain barrier epilepsy epilepsy-associated depression-like behavior neuroinflammation pentylenetetrazol pilocarpine tight junction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：