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Cobalt-Catalyzed Switchable[4.1]and[4.1+1]Spirocyclization of Aromatic Amides with 2-Diazo-1H-indene-1,3.2H)-dione:Access to Spiro Indene-2,1'-isoindolinones and Spiro Isochroman-3.1'-isoindolinones

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Chinese Journal of Chemistry 2024年第4期42卷 363-369页

作者： Bin Li Mengmeng Xie Jingyu Li nana Shen Xinying Zhang Xuesen Fan State Key Laboratory of Antiviral Drugs Pingyuan LaboratoryKey Laboratory of Green Chemical Media and ReactionsKey Laboratory for Yellow River and Huai River Water Environmental Pollution ControlMinistry of EducationSchool of EnvironmentSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China

Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3.1'-isoindolinones through cobalt-catalyzed formal[4.1]and[4.1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3.2H)-*** the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4.1]*** the reaction is run under O2 in CH3.N,on the other hand,spiro isochroman-3.1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen *** general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.

关键词： Spiro indene-2,1'-isoindolinones Spiro isochroman-3.1'-isoindolinones 3. Transition metals Cobalt-catalyzed C-H Activation Switchable[4.1]and[4.1+1]spirocyclization Aromatic amides 2-Diazo-1H-indene-1,3.2H)-dione

OPTIMAL CONTROL OF MULTISOLUTION ORDINARY DIFFERENTIAL EQUATIONS IN THE ABSENCE OF CONVEXITY

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Journal of Systems Science & Complexity 2010年第2期23卷 321-333页

作者： Shu luan Hang GAO school of Mathematics and Computation Science Zhanjiang Normal College Zhanjiang 524048 China. school of Mathematics and Statistics Northeast Normal University Changchun 130024 China.

In this paper,the authors study an optimal control problem governed by a class of multistateordinary differential equations in the absence of *** overcome the difficulty that thecorresponding approximate optimal control problem may have no solution,relaxed controls are *** the help of relaxation theory,Pontryagin's maximum principle for the optimal pairs ofthe original control problem is *** the end of this paper,the authors discuss the applicationof the maximum principle by an example.

关键词： Multisolution ODEs optimal control Pontryagin's maximum principle relaxed controls.

Local field potentials,spiking activity,and receptive fields in human visual cortex

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Science china(Life sciences) 2024年第3期67卷 543-554页

作者： Lu Luo Xiongfei Wang Junshi Lu Guanpeng Chen Guoming luan Wu Li Qian Wang Fang Fang school of Psychological and Cognitive sciences and Beijing Key Laboratory of Behavior and Mental Health Peking UniversityBeijing 100871China school of Psychology Beijing Sport UniversityBeijing 100084China Department of Neurosurgery Sanbo Brain HospitalCapital Medical UniversityBeijing 100093China Beijing Key Laboratory of Epilepsy Epilepsy CenterSanbo Brain HospitalCapital Medical UniversityBeijing 100093China IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China Peking-Tsinghua Center for Life sciences Peking UniversityBeijing 100871China Beijing Institute for Brain Disorders Beijing 100069China State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China

The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2/V3.. We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–3. Hz) were larger than those estimated from low-gamma activity(LGA, 3.–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.

关键词： human visual cortex receptive field intracranial EEG local field potential spiking activity

Three-dimensional porous In_(2)O_(3. arrays for self-powered transparent solar-blind photodetectors with high responsivity and excellent spectral selectivity

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Nano Research 2024年第5期17卷 4471-4477页

作者： nana Zhang Xinyu Gao Haoran Guan Simin Sun Jiaming Liu Zhitao Shao Qiyue Gao Yuan Zhang Ruyu Sun Guang Yang Feng Gao Wei Feng College of Chemistry Chemical Engineering and Resource UtilizationNortheast Forestry UniversityHarbin 150040China Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China

Transparent solar-blind ultraviolet photodetectors(SBUV PDs)have extensive applications in versatile scenarios,such as optical ***,it is still challenging to simultaneously achieve high responsivity,high transparency,and satisfying self-powered ***,we demonstrated high-performance,transparent,and self-powered photoelectrochemical-type(PEC)SBUV PDs based on vertically grown ultrathin In_(2)O_(3. nanosheet arrays(NAs)with a three-dimensional(3.)porous *** 3. porous structure simultaneously improves the transmittance in the visible light region,accelerates interfacial reaction kinetics,and promotes photogenerated carrier *** performance of In_(2)O_(3. NAs photoanodes exceeds most reported self-powered PEC SBUV PDs,exhibiting a high transmittance of approximately 80%in the visible light region,a high responsivity of 86.15 mA/W for 254.nm light irradiation,a fast response speed of 15/18 ms,and good multicycle *** In_(2)O_(3. NAs also show excellent spectral selectivity with an ultrahigh solar-blind rejection ratio of 13.9.3.,attributed to the quantum confinement effect induced by the ultrathin feature(2-3.nm).Furthermore,In_(2)O_(3. NAs photoanodes show good capability in underwater optical *** work demonstrated that a 3. porous structure is a powerful strategy to synchronously achieve high responsivity and transparency and provides a new perspective for designing high-performance,transparent,and self-powered PEC SBUV PDs.

关键词： In_(2)O_(3. three-dimensional porous transparent photoelectrochemical solar-blind photodetectors

Anion cascade reactions Ⅲ:Synthesis of 3.isoquinuclidone bridged polycyclic lactams

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Chinese Chemical Letters 2024年第2期35卷 426-430页

作者： Zhiguo Zhang Bingbing Shi Xiyang Cao nana Ma Hao Wu Xingjie Zhang Guisheng Zhang Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Centre of Henan Province for Green Manufacturing of Fine ChemicalsNMPA Key Laboratory for Research and Evaluation of Innovative DrugSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China

Bridged polycyclic lactams are important structural units in organic functional materials,natural products,and pharmaceuticals.A flexible and efficient anion cascade reaction was developed for the preparation of bridged polycyclic lactams from readily available malonamides and 1,4.*** highly substituted bridged polycyclic lactams were synthesized in good to excellent yields by tandem nucleophilic sequences in the presence of t BuOK in commercially available EtOH solvent at 60℃.Notably,the simple reactions can be run on a gram ***,bis-Michael addition reaction and hemiaminalization reactions are involved in the tandem transformation.

关键词： Anion cascade reactions 3.Isoquinuclidone Bridged polycyclic lactams Bis-Michael addition reaction Hemiaminalization

IRE1α regulates the PTHrP-IHH feedback loop to orchestrate chondrocyte hypertrophy and cartilage mineralization

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Genes & Diseases 2024年第1期11卷 464-478页

作者： Mengtian Fan nana Geng Xingyue Li Danyang Yin Yuyou Yang Rong Jiang Cheng Chen Naibo Feng Li Liang Xiaoli Li Fengtao Luo Huabing Qi Qiaoyan Tan Yangli Xie Fengjin Guo Laboratory of Developmental Biology Department of Cell Biology and GeneticsSchool of Basic Medical ScienceChongqing Medical UniversityChongqing 400016China Laboratory of Stem Cells and Tissue Engineering School of Basic Medical ScienceChongqing Medical UniversityChongqing 400016China Department of Orthopedics The 1st Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Wound Repair and Rehabilitation Medicine State Key Laboratory of TraumaBurns and Combined InjuryTrauma CenterResearch Institute of SurgeryDaping HospitalArmy Medical UniversityChongqing 400042China

Cartilage development is controlled by the highly synergistic proliferation and differentiation of growth plate chondrocytes,in which the Indian hedgehog(IHH)and parathyroid hormone-related protein-parathyroid hormone-1 receptor(PTHrP-PTH1R)feedback loop is *** inositol-requiring enzyme 1a/X-box-binding protein-1 spliced(IRE1α/XBP1s)branch of the unfolded protein response(UPR)is essential for normal cartilage ***,the precise role of ER stress effector IRE1α,encoded by endoplasmic reticulum to nucleus signaling 1(ERN1),in skeletal development remains ***,we reported that loss of IRE1α accelerates chondrocyte hypertrophy and promotes endochondral bone ***1 acts as a negative regulator of chondrocyte proliferation and differentiation in postnatal growth *** deficiency interrupted PTHrP/PTH1R and IHH homeostasis leading to impaired chondrocyte hypertrophy and ***1s,produced by p-IRE1α-mediated splicing,binds and up-regulates PTH1R and IHH,which coordinate cartilage ***,ER stress cannot be activated normally in ERN1-deficient *** conclusion,ERN1 deficiency accelerates chondrocyte hypertrophy and cartilage mineralization by impairing the homeostasis of the IHH and PTHrP/PTH1R feedback loop and ER ***1 may have a potential role as a new target for cartilage growth and maturation.

关键词： Cartilage development ER stress ERN1 IHH PTHrP/PTH1R

Weak Galerkin finite element method for valuation of American options

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Frontiers of Mathematics in china 2014年第2期9卷 455-476页

作者： Ran ZHANG Haiming SONG nana luan school of Mathematics Jilin University Changchun 130012 China school of Insurance and Economics University of International Business and Economics Beijing 100190 China

We introduce a weak Galerkin finite element method for the valuation of American options governed by the Black-Scholes equation. In order to implement, we need to solve the optimal exercise boundary and then introduce an artificial boundary to make the computational domain bounded. For the optimal exercise boundary, which satisfies a nonlinear Volterra integral equation, it is resolved by a higher-order collocation method based on graded meshes. With the computed optimal exercise boundary, the front-fixing technique is employed to transform the free boundary problem to a one- dimensional parabolic problem in a half infinite area. For the other spatial domain boundary, a perfectly matched layer is used to truncate the unbounded domain and carry out the computation. Finally, the resulting initial-boundary value problems are solved by weak Galerkin finite element method, and numerical examples are provided to illustrate the efficiency of the method.

关键词： American option optimal exercise boundary weak Galerkin finite element method

OsFK1 encodes C-14.sterol reductase,which is involved in sterol biosynthesis and affects premature aging of leaves in rice

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The Crop Journal 2024年第4期12卷 1010-1021页

作者： Ping Li Xia Zhang Wuzhong Yin Yang Shui Jie Zhang nana Xu Dasong Bai Qingxiong Huang Yuanyuan Li Pan Qi Xing Li Qianlong Li Shihong Yang Guotao Yang Hong Chen Peng Qin Yungao Hu Youlin Peng Rice Research Institute School of Life Science and EngineeringSouthwest University of Science and TechnologyMianyang 621010SichuanChina Hainan Yazhou Bay Seed Laboratory Sanya 572025HainanChina Rice Research Institute State Key Laboratory of Crop Gene Exploration and Utilization in Southwest ChinaSichuan Agricultural UniversityChengdu 610061SichuanChina Yazhouwan National Laboratory Sanya 572704HainanChina

The enzyme C-14.sterol reductase is involved in biosynthesis of brassinosteroids(BR)and sterols,as well as plant ***1,a member of the sterol biosynthesis pathway located in the endoplasmic reticulum(ER),encodes C-14.sterol ***,there is little research on the function of C-14.sterol reductase in *** with the wild type,an osfk1 mutant showed dwarf phenotype and premature aging in the second leaf during the trefoil stage,and abnormal development of leaf veins during the tillering *** osfk1 mutant showed signs of aberrant PCD,as evidenced by TUNEL *** suggested that high ROS buildup caused DNA damage and ROS-mediated cell death in the *** osfk1 mutant also showed decreased chlorophyll content and aberrant chloroplast *** of the osfk1 mutant allele revealed a non-synonymous G to A mutation in the final intron,leading to early ***,we identified the OsFK1 allele,cloned it by Mutmap sequencing,and verified it by ***-MS/MS assays demonstrated that the osfk1 mutation caused lower phytosterol *** findings showed that the OsFK1 allele encoding C-14.sterol reductase is involved in phytosterol biosynthesis and mediates normal development of rice plants.

关键词： Leaf development ROS Phytosterol biosynthesis Rice

非社会的社会性:弥补人工智能责任缺口的一种纾困尝试

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医学与哲学 2024年第9期45卷 1-5页

作者：栾云镪南京师范大学马克思主义学院江苏南京210023

人工智能(artificial intelligence,AI)的突破性发展为人类提供诸多便利,但技术的社会属性引发了医学、哲学、法学等学科领域对其道德责任缺口问题的深层隐忧,争议的核心是AI技术发展是否可控,AI是否可以像人类一样具有能动性和体验性,... 详细信息

人工智能(artificial intelligence,AI)的突破性发展为人类提供诸多便利,但技术的社会属性引发了医学、哲学、法学等学科领域对其道德责任缺口问题的深层隐忧,争议的核心是AI技术发展是否可控,AI是否可以像人类一样具有能动性和体验性,如何提高AI的道德敏感度。“非社会的社会性”理论为弥补AI的道德缺口提供了一种纾困策略:将“人是目的”作为道德尺度,以人类自身责任主动把握智能技术伦理主动,重塑智能技术在人类社会中的限制条件,为引导其向负责任发展提供规范性道德指引。

关键词：非社会性社会性人工智能责任伦理边界伦理规范