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Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

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Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao Qin Dong Dan Zou zhijun Yang Lili guo Ruxiang Xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

Predicting landslide scenes under potential earthquake scenarios in the Xianshuihe fault zone, Southwest China

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Journal of Mountain Science 2017年第7期14卷 1262-1278页

作者： ZHANG Yong-shuang YANG zhi-hua guo chang-bao WANG Tao WANG Dong-hui DU guo-liang China Institute of Geo-Environment Monitoring Institute of Geomechanics Chinese Academy of Geological Sciences Chengdu Center China Geological Survey

Earthquake-induced landslides can seriously aggravate the earthquake's destructive consequences and have caused widespread concern in recent decades. The Xianshuihe fault is a large active left-lateral strike-slip fault in the southeast margin of Qinghai-Tibet Plateau, Southwest China, where the frequent strong earthquakes have brought abundant geo-hazards. This study focuses mainly on exploring and predicting the landslide scenes induced by the potential earthquakes. Firstly, the sophisticated Newmark model is improved through landslide cases induced by the Ms7.9 Luhuo earthquake in 1973 to adapt the field seismotectonics of the Xianshuihe fault zone. Then, it is used to predict the landslide scenes under one speculated potential earthquake scenario with the similar focal mechanism with the Luhuo earthquake. The preliminary results show that the slope displacement resulted from Newmark model can reflect spatial distribution characteristics ofearthquake-induced landslides. The predicted potential earthquake-induced landslide scenes present an obvious extending trend along the Xianshuihe fault. The landslide hazard is greater in the northeast regions than southwest regions of the Xianshuihe fault, where there are more complex topographic conditions. The study procedure will be a helpful demonstration for exploration and prediction of landslide scenes under potential earthquakes in the regions with high seismic activity.

关键词： Qinghai-Tibet Plateau Xianshuihe fault Potential earthquake Landslide Newmark model

Variation of sea ice and perspectives of the Northwest Passage in the Arctic Ocean

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Advances in Climate change Research 2021年第4期12卷 447-455页

作者： CHEN Jin-Lei KANG Shi-chang guo Jun-Ming XU Min ZHANG zhi-Min State Key Laboratory of Cryosphere Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Centre for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing100101China Gansu Construction Vocational Technology College Lanzhou730000China

The continued warming of the Arctic atmosphere and ocean has led to a record retreat of sea ice in the last *** retreat has increased the probability of the opening of the Arctic Passages in the near *** Northwest Passage(NWP)is the most direct shipping route between the Atlantic and Pacific Oceans,producing notable economic *** variations of sea ice and its influencing factors from a high-resolution unstructured-grid finite-volume community ocean model were investigated along the NWP in 1988-2016,and the accessibility of the NWP was assessed under shared socioeconomic pathways(SSP245 and 585)and two vessel classes with the Arctic transportation acces-sibility model in *** ice thickness has decreased with increasing seawater temperature and salinity,especially within the Canadian Arctic Archipelago(CAA)in 1988-2016,which has facilitated the opening of the *** ship navigation is projected to be possible for polar class 6 ships in August-December in 2021-2025,after when it may extends to July under SSP585 in 2026-2030,while open water ships will not be able to pass through the NWP until September in mid-21st *** navigability of the NWP is mainly affected by the ice within the *** the accessibility of the Parry Channel,the west part is worse than that of the eastern part,especially in the Viscount-Melville Sound.

关键词： Arctic Sea ice Northwest passage Canadian arctic archipelago Strait

Side-chain engineering of high-efficiency conjugated polymer photovoltaic materials

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Science China Chemistry 2015年第2期58卷 192-209页

作者： zhi-guo Zhang Yongfang Li Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Laboratory of Advanced Optoelectronic Materials College of Chemistry Chemical Engineering and Materials Science Soochow University

In recent years,conjugated polymers have attracted great attention in the application as photovoltaic donor materials in polymer solar cells(PSCs).Broad absorption,lower-energy bandgap,higher hole mobility,relatively lower HOMO energy levels,and higher solubility are important for the conjugated polymer donor materials to achieve high photovoltaic ***-chain engineering plays a very important role in optimizing the physicochemical properties of the conjugated *** this article,we review recent progress on the side-chain engineering of conjugated polymer donor materials,including the optimization of flexible side-chains for balancing solubility and intermolecular packing(aggregation),electron-withdrawing substituents for lowering HOMO energy levels,and two-dimension(2D)-conjugated polymers with conjugated side-chains for broadening absorption and enhancing hole *** the molecular structural optimization by side-chain engineering,the2D-conjugated polymers based on benzodithiophene units demonstrated the best photovoltaic performance,with powerconversion efficiency higher than 9%.

关键词： polymer solar cells conjugated polymers side-chain engineering photovoltaic materials 2D-conjugated polymers

Backstepping Approach to the Adaptive Regulator Design for a One-Dimensional Wave Equation with General Input Harmonic Disturbance

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Journal of Systems Science & Complexity 2017年第2期30卷 253-279页

作者： guo Wei SHAO zhi-Chao Department of Applied Mathematics School of StatisticsUniversity of International Business and EconomicsBeijing 100029China

This paper considers the parameter estimation and stabilization of an unstable one-dimen- sional wave equation with matched general harmonic disturbance at the controlled end. The back- stepping method for infinite-dimensional system is adopted in the design of the adaptive regulator. It is shown that the resulting closed-loop system is asymptotically stable. Meanwhile, the estimated parameter is shown to be convergent to the unknown parameter as time unes tn ~n^nitv

关键词： Backstepping method distributed parameter system disturbance rejection stability.

Effect of Dy substitution on the microstructure and magnetic properties of nanograin Nd-Fe-B single-phase alloys

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 335-339页

作者： zhi-an Chen Ji Luo zhi-meng guo School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nanocrystalline single-phase alloys with the nominal compositions （at%） of Nd12.3-xDyxFe79.7Zr0.8Nb0.8Cu0.4B6.0 （x=0, 0.5, 1.5, and 2.5） were prepared by melt-spinning and subsequent annealing. X-ray diffraction analysis shows that the as-spun ribbons were mainly com- posed of the amorphous phase. A slight content of Dy stabilizes the amorphous phase during annealing treatment. The grain size becomes smaller and the coercivity of the annealed ribbon is gradually improved with the increase of Dy content. Excessive Dy is harmful to the remanence. It is found that no intergramtlar phase exists between the grains by high-resolution transmission electron microscopy, and the grain boundaries are crystallographically coherent in the optimally annealed sample. The optimum magnetic properties of remanence （Jr=1.09 T）, coercivity （Hei=1048 kA/m）, and maximum magnetic energy product （（BH）m=169.5 kJ/m3） are obtained from the x=0.5 ribbon in a post heat-treated state （700℃, 10 min）.

关键词： NdFeB magnets dysprosium nanocrystalline amorphous grain size magnetic properties

The School that changes Mindsets

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China Today 2025年第1期74卷 62-64页

作者： guo QING KONG SIQI 不详

China’s highest-altitude primary school is not only teaching children of farmers and herders but their parents as *** Sinopec Primary School in Nagqu,a city in Xizang Autonomous Region in southwest China,is known as the school“the closest to the sky”due to its high-altitude location-a breathtaking 4,700 meters above sea *** by oil and gas giant Sinopec as part of its corporate social responsibility,the school opened in 2012 and has since become a microcosm of China’s drive for education,especially in remote and rural areas,to ensure that no one is left behind.

关键词： altitude farmers southwest

Gain and phase errors active calibration method based on neural network for arrays with arbitrary geometry

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The Journal of China Universities of Posts and Telecommunications 2023年第2期30卷 8-17页

作者： Han Ziwen Zhang zhi guo Yu State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The manifold matrix of the received signals can be destroyed when the array is with the gain and phase errors,which will affect the performance of the traditional direction of arrival(DOA)estimation *** this paper,a novel active array calibration method for the gain and phase errors based on a cascaded neural network(GPECNN)was *** cascaded neural network contains two parts:signal-to-noise ratio(SNR)classification network and two sets of error estimation *** calibration subnetworks are activated according to the output of the SNR classification network,each of which consists of a gain error estimation network(GEEN)and a phase error estimation network(PEEN),*** disadvantage of neural network topology architecture is changing when the number of array elements varies is addressed by the proposed group calibration ***,due to the data characteristics of the input vector,the cascaded neural network can be applied to arrays with arbitrary geometry without repetitive *** results demonstrate that the GPECNN not only achieves a better balance between calibration performance and calibration complexity than other methods but also can be applied to arrays with different numbers of sensors or different shapes without repetitive training.

关键词： active array calibration cascaded neural network direction of arrival(DOA)estimation

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Tetra-detector size exclusion chromatography characterization of molecular and solution properties of soluble microbial polysaccharides from an anaerobic membrane bioreactor

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Frontiers of Environmental Science & Engineering 2017年第2期11卷 165-174页

作者： Qingbin guo Sheng chang School of Engineering University of Guelph Guelph Ontario N 1G 2W1 Canada

Characterization of the molecular properties of soluble microbial products （SMP） is critical for understanding the membrane filtration and fouling mechanisms in anaerobic and aerobic membrane bioreactors （AnMBR ＆ MBR）. In this study, the distributions of the absolute molecular weight and intrinsic viscosity of SMP polysaccharides from an AnMBR were effectively determined by a high pertbrmance size exclusion chromatography （HPSEC） that was coupled with the refractive index （RI）,cliode array UV （DAUV）, right and low angle light scattering （LS）, and viscometer （Vis） detectors. Based on the tetra-detector HPSEC determined absolute molecular weights and intrinsic viscosity, a universal calibration relationship for the SMP polysaccharides was developed and the molecularconformations, average molecular weights~ and hydrodynamic sizes of the SMP polysaccharides were also explored. Two factors which can be derived from the tetra-detector HPSEC analysis were proposed for the characterization of the viscous and osmotic pressure properties of the SMP polysaccharides. In addition, it was also extrapolated how to analyze the resistance characteristics of the concentration polarization layers formed in membrane filtration based on the molecular properties determined by the tetra-detector HPSEC analysis.

关键词： Soluble microbial productExtracellular polymeric substanceMembrane bioreactorMembrane foulingMolecular weightIntrinsic viscosity