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Inducible regulation of GDNF expression in human neural stem cells

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Science China(Life Sciences) 2013年第1期56卷 32-39页

作者： WANG ShuYan REN Ping guan yunqian ZOU ChunLin FU LinLin ZHANG Yu Cell Biology Room Xuanwu HospitalCapital Medical Universityand Key Laboratory of NeurodegenerationMinistry of Education

Glial cell derived neurotrophic factor （GDNF） holds promises for treating neurodegenerative diseases such as Parkinson＇s dis- ease. Human neural stem cells （hNSCs） have proved to be a suitable cell delivery vehicle for the safe and efficient introduction of GDNF into the brain. In this study, we used hNSCs-infected with a lentivirus encoding GDNF and the hygromycin re- sistance gene as such vehicles. A modified tetracycline operator 7 （tetO7） was inserted into a region upstream of the EFI-α promoter to drive GDNF expression. After hygromycin selection, hNSCs were infected with a lentivirus encoding a KRAB-tetracycline repressor fusion protein （TTS）. TTS bound to tetO7 and suppressed the expression of GDNF in hNSCs. Upon administration of doxycycline （Dox） the TTS-tetO7 complex separated and the expression of GDNF resumed. The hNSCs infected with GDNF expressed the neural stem cell specific markers, nestin and sox2, and exhibited no significant change in proliferation rate. However, the rate of apoptosis in hNSCs expressing GDNF was lower compared with normal NSCs in response to actinomycin treatment. Furthermore, a higher percentage of Tuj-I positive cells were obtained from GDNF-producing NSCs under conditions that induced differentiation compared to control NSCs. The inducible expression of GDNF in hNSCs may provide a system for the controllable delivery of GDNF in patients with neurodegenerative diseases.

关键词： neural stem cells GDNF lentivirus vectors tetracycline operator

The stress-thermal equivalence“memory effect”in glass materials

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 175-176页

作者： Pengfei guan Beijing Computational Science Research Center Beijing 100193China

Glass materials,including metallic,organic,and silicate glasses,are crucial in various engineering applications due to their unique disordered atomic packing ***,these materials suffer from stress decay under constant... 详细信息

关键词： glasses glass stress

A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1171-1188页

作者： Wei WEI Feng guan Xin FANG College of Intelligent Science National University of Defense TechnologyChangsha410073China Naval Research Academy Beijing100161China

A metamaterial vibration isolator,termed as wave-insulating isolator,is proposed,which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave *** consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and *** bandgap mechanisms,vibration isolation properties,effects of key parameters,and robustness to complex conditions are *** experimentally demonstrated,the wave-insulating isolator can improve the vibration insulation in the ranges of[50 Hz,180 Hz]and[260 Hz,400 Hz]by 15 dB and 25 dB,respectively,in contrast to the conventional isolator with the same first resonant frequency.

关键词： metamaterial and metastructure vibration isolation bandgap wave insulation plate

Brain Mechanisms Underlying Panic Attack and Panic Disorder

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Neuroscience Bulletin 2024年第6期40卷 795-814页

作者： Xuyan guan Peng Cao Tsinghua Institute of Multidisciplinary Biomedical Research Tsinghua UniversityBeijing102206China National Institute of Biological Sciences(NIBS) Beijing102206China

Panic disorder is a psychiatric disorder characterized by recurrent panic attacks,with a prevalence of~4%in the general population,causing heavy personal and socioeconomic *** similarities of animal defense responses to clinical panic attack symptoms in humans make it possible to translate neuroanatomical pathways identified in animal studies to panic disorder in ***,in this review we first present a basic overview of panic disorder in humans including the main subtypes,models commonly used to trigger panic attacks,related hypotheses,the neurotransmitter systems that may be involved,and the current clinical treatments to give the reader a comprehensive understanding of panic *** animal section introduces the models that trigger panic-like behavior in animals and the brain regions that may be involved,providing insights for future elucidation of the neural circuit mechanisms behind panic attacks.

关键词： Panic disorder Panic attack Defense responses Animal studies Humans

3D Localization for Multiple AUVs in Anchor-Free Environments by Exploring the Use of Depth Information

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1051-1053页

作者： Yichen Li Wenbin Yu Xinping guan the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai Jiao Tong UniversityShanghai 200240China

Dear Editor,This letter investigates the cooperative localization problem for multiple autonomous underwater vehicles(AUVs)in underwater anchor-free environments,where AUV localization errors grow without bound due to the accumulated errors in inertial measurements(termed accumulated errors hereafter)and the lack of anchors(with known positions).

关键词： AUVs underwater hereafter

Proactive Resilience Enhancement of Power Systems with Link Transmission Model-based Dynamic Traffic Assignment Among Electric Vehicles

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1320-1330页

作者： Haoyuan Yan Tianyang Zhao Zhanglei guan Energy Electricity Research Center Jinan UniversityGuangzhou 510632China Energy Research Institute Nanyang Technological UniversitySingapore IEEE

The rapid development of electric vehicles(EVs)is strengthening the bi-directional interactions between electric power networks(EPNs)and transportation networks(TNs)while providing opportunities to enhance the resilience of power systems towards extreme *** quantify the temporal and spatial flexibility of EVs for charging and discharging,a novel dynamic traffic assignment(DTA)problem is *** DTA problem is based on a link transmission model(LTM)with extended charging links,depicting the interaction between EVs and power *** models the charging rates as continuous variables by an energy boundary *** consider the evacuation requirements of TNs and the uncertainties of traffic conditions,the DTA problem is extended to a two-stage distributionally robust *** is further incorporated into a two-stage distributionally robust unit commitment problem to balance the enhancement of EPNs and the performance of *** problem is reformulated into a mixed-integer linear programming problem and solved by off-the-shelf commercial *** studies are performed on two test *** effectiveness is verified by the numerical results,e.g.,reducing the load shedding amount without increasing the unmet traffic demand.

关键词： Coupled transportation and power network link transmission model resilience enhancement

Reduced magma generation and its implications for the Pulang giant porphyry Cu-polymetallic deposit in Northwest Yunnan,China

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Acta Geochimica 2024年第4期43卷 802-813页

作者： Jingwei guan Tao Ren Lei Wang Shenjin guan Lianrong Wu Baosheng Shi Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093People’s Republic of China Diqing Nonferrous Metals Co. LtdShangri-La 674400People’s Republic of China

The Pulang giant porphyry Cu-Mo polymetallic deposit is located in the Zhongdian area in the center of the Sanjiang Tethys tectonic domain,which was formed by the westward subduction of the Garze-Litang oceanic slab beneath the Zhongza ***-pyrrhotite-pyritemolybdenite occurs as disseminations,veins,veinlets,and stockworks distributed in the K-silicate alteration zone in the monzonite porphyry,which is superimposed by *** chemical compositions of biotite and amphibole analyzed by electron probe microanalysis(EPMA)indicate that the ore-forming magma and exsolved fluids experienced a continuous decrease in the oxygen fugacity(fO_(2)).Primary amphibolite and biotite(type I)crystallized at relatively high temperatures(744-827°C)and low fO_(2)(log fO_(2)=−12.26 to−11.91)during the magmatic *** fluids exsolved from the magma have a relatively lower temperature(621-711°C)and fO_(2)(log fO_(2)=−14.36 to−13.32)than the original *** addition,the presence of a high abundance of pyrrhotite and an insufficiency of primary magnetite and sulfate in the ore(i.e.,anhydrite and gypsum)indicate that the deposit may be a reduced porphyry *** and fluid fO_(2)results,combined with previous research on magmatic fO_(2)at the Pulang deposit,indicate that the magma associated with the reduced Pulang ore assemblages was initially generated as a highly oxidized magma that was subsequently reduced by sedimentary rocks of the Tumugou Formation.

关键词： Porphyry deposit Oxygen fugacity(fO_(2)) Contamination of surrounding rock Pulang Zhongdian arc

Automatic Requirement Dependency Extraction Based on Integrated Active Learning Strategies

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Machine Intelligence Research 2024年第5期21卷 993-1010页

作者： Hui guan Guorong Cai Hang Xu Department of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China Key Laboratory of Industrial Intelligence Technology on Chemical Process Shenyang110142China

Since requirement dependency extraction is a cognitively challenging and error-prone task,this paper proposes an automatic requirement dependency extraction method based on integrated active learning *** this paper,the coefficient of variation method was used to determine the corresponding weight of the impact factors from three different angles:uncertainty probability,text similarity difference degree and active learning variant prediction divergence *** combining the three factors with the proposed calculation formula to measure the information value of dependency pairs,the top K dependency pairs with the highest comprehensive evaluation value are selected as the optimal *** the optimal samples are continuously added into the initial training set,the performance of the active learning model using different dependency features for requirement dependency extraction is rapidly ***,compared with other active learning strategies,a higher evaluation measure of requirement dependency extraction can be achieved by using the same number of ***,the proposed method using the PV-DM dependency feature improves the weight-F1 by 2.71%,the weight-recall by 2.45%,and the weight-precision by 2.64%in comparison with other strategies,saving approximately 46%of the labelled data compared with the machine learning approach.

关键词： Requirement dependency dependency extraction dependency features integrated active learning strategies coefficient of variation

W-band millimeter wave vialess microstrip-to-microstrip vertical transition in multilayer LCP substrate

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The Journal of China Universities of Posts and Telecommunications 2024年第3期31卷 87-94页

作者： Liu Weihong Zhang Xu guan Dongyang School of Electronic Engineering Xian University of Posts and TelecommunicationsXi'an 710121China

In this paper,a W-band broadband vialess microstrip(MS)-to-MS vertical transition in multilayer liquid crystal polymer(LCP)substrate is presented,which consists of two MS lines in the top layer,a common ground plane and slotline resonators in the second layer,and a close-loop transmission-line in the third *** increase the passband of the vialess vertical transition,an H-shaped slotline resonator is introduced,which greatly improves the impedance performance of the slotline resonator,and the full-wave simulated results indicate that insertion loss(IL)is less than 2 dB and return loss(RL)is better than 10 dB at *** verify this design,the broadband vertical transition is fabricated and *** measured results indicate that a broadband vertical transition with RL better than 10 dB and IL less than 5.67 dB can be obtained in the frequency range from 70.00 GHz to 104.09 *** to the fabrication error in the preparation process,the measured results are deteriorated compared to the simulated results,and the investigation indicates that the deviation is caused by the thickness error of the LCP substrate.

关键词： W-band broadband microstrip(MS)-to-MS vialess vertical transition liquid crystal polymer(LCP)