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Recent advances in the construction of axially chiral arylpyrroles

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Science China Chemistry 2023年第9期66卷 2480-2491页

作者： yang-Bo Chen ye-Nan yang Xuan-Zhu Huo Long-Wu ye Bo Zhou Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid SurfacesCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Catalytic enantioselective preparation of axially chiral molecules has gained considerable interest over the past decades, due to their numerous applications in bioactive molecules, natural products, pharmaceuticals, materials, ligands, and catalysts. Compared with the well-established synthetic approaches for six-membered axially chiral skeletons, methodologies directed towards five-membered axially chiral compounds are relatively rare. Among these, axially chiral arylpyrroles are especially important structural motifs with wide utility, and the atroposelective synthesis of them is highly desirable. In recent years, novel strategies have been developed based on transition-metal catalysis and organocatalysis. This review summarizes the recent achievements in atroposelective preparation of arylpyrroles, by emphasizing the synthetic methods for each axially chiral framework, reaction mechanisms, and applications.

关键词： axial chirality pyrrole atropisomers transition-metal catalysis organocatalysis

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Celastrol promotes apoptotic cell death in children neuroblastoma cells through caspases dependent pathway

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Journal of Traditional Chinese Medicine 2022年第6期42卷 877-884页

作者： yang ye ZHANG Aihui LI Anmao Department of Thoracic Surgery Xi'an Children's HospitalXi'an 710003China

OBJECTIVE: To investigate the in-depth pharmacological mechanisms of celastrol in children neuroblastoma treatment. METHODS: In the current study, we examined the effects of celastrol on children neuroblastoma cells viability and proliferation by cell counting kit-8 assay and colony formation assay. Annexin V-FTIC and PI staining were applied to determine cell apoptosis after celastrol treatment. ROS generation levels were examined by 2′, 7′-dichloroflfluorescin diacetate. RESULTS: We found that celastrol could suppress the proliferation of children neuroblastoma cells with few effects on normal cell lines in vitro. Further mechanisms studies have shown that celastrol inhibited cell cycle progression and induced cell apoptosis in QDDQ-NM and SH-SY5Y cells. In addition, ROS production might involve in celastrol-mediated apoptotic cell death in children neuroblastoma cells by activating caspase death pathway. CONCLUSIONS: Our findings demonstrated that celastrol could promote ROS generation-induced apoptosis in neuroblastoma cell by activating caspase death pathway. These findings suggested that celastrol might be a potential novel anti-neuroblastoma agent with minor cytotoxicity.

关键词： neuroblastoma child celastrol apoptosis poly(ADP-ribose)polymerases

The effect of different generalized uncertainty principles on Jeans mass modification

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Communications in Theoretical Physics 2023年第10期75卷 129-137页

作者： ye-xing yang Zheng-wen Long College of Physics Guizhou UniversityGuiyang550025China

Jeans mass is regarded as a crucial factor in the study of nebula *** data shows that Jeans mass is larger in theory than it is in *** mentioned that Jeans mass can be modified by using the generalized uncertainty principle(GUP).However,different physical backgrounds lead to different forms of GUP *** order to make the theoretical values of Jeans mass and its observed values match better,we use three distinct types of GUPs to correct Jeans mass in this *** find that the corrected Jeans masses are smaller than the uncorrected ones,where the Pedram corrected Jeans mass is the minimum and is close to the observed *** addition,we consider the impact of temperature T and the GUP parameters(η,βandγ)for the corrected Jeans mass.

关键词： Jeans mass generalized uncertainty principle Newtonian gravity

Jittor: a novel deep learning framework with meta-operators and unified graph execution

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Science China(Information Sciences) 2020年第12期63卷 118-138页

作者： Shi-Min HU Dun LIANG Guo-ye yang Guo-Wei yang Wen-yang ZHOU Department of Computer Science and Technology Tsinghua University Beijing National Research Center for Information Science and Technology

This paper introduces Jittor, a fully just-in-time(JIT) compiled deep learning framework. With JIT compilation, we can achieve higher performance while making systems highly customizable. Jittor provides classes of Numpy-like operators, which we call meta-operators. A deep learning model built upon these meta-operators is compiled into high-performance CPU or GPU code in real-time. To manage metaoperators, Jittor uses a highly optimized way of executing computation graphs, which we call unified graph execution. This approach is as easy to use as dynamic graph execution yet has the efficiency of static graph execution. It also provides other improvements, including operator fusion, cross iteration fusion, and unified memory.

关键词： deep learning framework meta-operator unified graph execution JIT compilation generative adversarial network

Monitoring impact of mefenacet treatment on soil microbial communities by PCR-DGGE fingerprinting and conventional testing procedures

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Journal of Environmental Sciences 2006年第2期18卷 373-378页

作者： ye yang-fang MIN Hang LU Zhen-mei College of Life Science and Biotechnology Ningbo University Ningbo 315211 China College of Life Science Zhejiang University Hangzhou 310029 China

The effect of acetanilide herbicide mefenacet on soil microbial communities was studied using paddy soil samples with different short-term treatments. The culturable bacteria （plate counts）, dehydrogenase activity and changes in community structure （denaturing gradient gel electrophoresis （DGGE） analysis） were used for biological community assessments. Mefenacet was a significant stimulus to cultural aerobic bacteria and dehydrogenase activity while Sphingobacterium multivorum Y1, a bacterium efficiently degrading the mefenacet, only induced the increasing colony-forming unit （CFU） of bacteria but little effect on dehydrogenase activity during the whole experiment. The degree of similarity between the 16S rDNA profiles of the communities was quantified by numerically analyzing the DGGE band patterns. Similarity dendrograms showed that the microbial community structures of the mefenacet-treated and non-treated soils were not significantly different. But supplement of S. multivorum Y1 could increase the diversity of the microbial community in the mefenacet-polluted paddy soil. This work is a new attempt to apply the S. multivorum Y1 for remediation of the mefenacet-polluted environments.

关键词： denaturing gradient gel electrophoresis(DGGE) soil microbial diversity mefenacet dehydrogenase

Isocartormin, a novel quinochalcone C-glycoside from Carthamus tinctorius

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Acta Pharmaceutica Sinica B 2017年第4期7卷 527-531页

作者： Feng Li Zhisheng He yang ye State Key Laboratory of Drug Research and Natural Products Chemistry Department Shanghai Institute of Materia Medica Chinese Academy of Sciences Department of Molecular and Cellular Biology Baylor College of Medicine

A new semi-quinonechalcone C-glycoside isocartormin along with cartormin and saf fl omin C were isolated from the water extract of Carthamus tinctorius L. The structure of isocartormin was determined by extensive analysis of HR-MS, 1D-and 2D NMR data, and by comparison with those of cartormin reported previously by our group. Isocartormin was identified as a diastereoisomer of cartormin with a reverse configuration at C-18.

关键词： Carthamus tinctorius Compositae Semi-quinone chalcone Cartormin Isocartormin

The Extension Dimension of Subcategories and Recollements of Abelian Categories

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1042-1058页

作者： Xin MA ye yang PENG Zhao Yong HUANG College of Science Henan University of EngineeringZhengzhou 451191P.R.China Department of Mathematics Nanjing UniversityNanjing 210093P.R.China

We investigate the behavior of the extension dimension of subcategories of abelian categories under ***Λ',Λ,Λ"be art in algebras such that(modΛ',mod A,modΛ")is a recollement,and let D'and D"be subcategories of modΛand modΛ"*** any n,m≥0,under some conditions,we get dimΩ^(k)(D)≤dimΩ^(n)(D')+dimΩ^(m)(D")+1,where k=max{m,n}and D is the subcategory of modΛglued by D'and D";moreover,we give a sufficient condition such that the converse inequality holds *** applications,some results for Igusa-Todorov subcategories and syzygy finite sub categories are obtained.

关键词： Recollements extension dimension Igusa–Todorov subcategories syzygy finite subcategories

Alternative splicing and cancer: a systematic review

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Signal Transduction and Targeted Therapy 2021年第3期6卷 807-820页

作者： Yuanjiao Zhang Jinjun Qian Chunyan Gu ye yang The Third Affiliated Hospital of Nanjing University of Chinese Medicine NanjingChina School of Medicine&Holistic Integrative Medicine Nanjing University of Chinese MedicineNanjingChina

The abnormal regulation of alternative splicing is usually accompanied by the occurrence and development of tumors,which would produce multiple different isoforms and diversify protein *** aim of the present study was to conduct a systematic review in order to describe the regulatory mechanisms of alternative splicing,as well as its functions in tumor cells,from proliferation and apoptosis to invasion and metastasis,and from angiogenesis to *** abnormal splicing events contributed to tumor progression as oncogenic drivers and/or bystander *** alterations in splicing factors detected in tumors and other mis-splicing events(i.e.,long non-coding and circular RNAs)in tumorigenesis were also *** findings of recent therapeutic approaches targeting splicing catalysis and splicing regulatory proteins to modulate pathogenically spliced events(including tumor-specific neo-antigens for cancer immunotherapy)were *** emerging RNA-based strategies for the treatment of cancer with abnormally alternative splicing isoforms were also ***,further studies are still required to address the association between alternative splicing and cancer in more detail.

关键词： expression. invasion alterations

Design and Fabrication of Reflective Phase Shifter for Two-Dimensional Terahertz Beam-Scanning Reflectarray

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Chinese Journal of Electronics 2022年第3期31卷 581-588页

作者： yang Jun YIN Mingjun GAO Haoyu YIN Zhiping ye yang DENG Guangsheng LU Hongbo Special Display and Imaging Technology Innovation Center of Anhui Province Academy of Opto-electric TechnologyHefei University of Technology Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing Guilin University of Electronic Technology Space Star Technology Co. Ltd.

A reflective phase shifter is proposed to realize the two-dimensional beam-scanning *** reflectarray is composed of double-dipole resonant elements in which the phase shift is implemented by applying a driving voltage to the liquid crystal(LC). A 30 ×30 phase shifter sample is fabricated on a quartz substrate with a 480 μm thickness and a 4 cm × 4 cm *** to the experimental results, 0 to 360° phase shift can be achieved within the bandwidth of 5 GHz. In order to accomplish two-dimensional beam-scanning and reduce the negative impact of driving lines on the reflectarray, a new LC driving method is developed. To verify the accuracy of the proposed approach, three samples of different driving line numbers are designed using the above-mentioned phase shifter, which all have achieved a0-360° phase shift in the bandwidth of 4 GHz. Considering the influence of LC anisotropy and inhomogeneity, an improved calculation result is obtained and compared with experimental data.

关键词： liquid crystals phase shifters above-mentioned phase shifter reflective phase shifter double-dipole resonant elements submillimetre wave antennas LC anisotropy two-dimensional terahertz beam-scanning reflectarray driving voltage dipole antenna arrays scanning antennas driving line numbers LC driving method reflectarray antennas