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Chondroitinase ABC combined with Schwann cell transplantation enhances restoration of neural connection and functional recovery following acute and chronic spinal cord injury
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作者 Wenrui Qu Xiangbing Wu +13 位作者 Wei Wu Ying Wang Yan Sun Lingxiao Deng Melissa Walker Chen Chen Heqiao Dai Qi Han Ying Ding Yongzhi Xia George Smith Rui Li Nai-Kui Liu Xiao-Ming Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1467-1482,共16页
Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration... Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration-approved Phase I clinical trial has been conducted to evaluate the safety of transplanted human autologous Schwann cells to treat patients with spinal cord injury.A major challenge for Schwann cell transplantation is that grafted Schwann cells are confined within the lesion cavity,and they do not migrate into the host environment due to the inhibitory barrier formed by injury-induced glial scar,thus limiting axonal reentry into the host spinal cord.Here we introduce a combinatorial strategy by suppressing the inhibitory extracellular environment with injection of lentivirus-mediated transfection of chondroitinase ABC gene at the rostral and caudal borders of the lesion site and simultaneously leveraging the repair capacity of transplanted Schwann cells in adult rats following a mid-thoracic contusive spinal cord injury.We report that when the glial scar was degraded by chondroitinase ABC at the rostral and caudal lesion borders,Schwann cells migrated for considerable distances in both rostral and caudal directions.Such Schwann cell migration led to enhanced axonal regrowth,including the serotonergic and dopaminergic axons originating from supraspinal regions,and promoted recovery of locomotor and urinary bladder functions.Importantly,the Schwann cell survival and axonal regrowth persisted up to 6 months after the injury,even when treatment was delayed for 3 months to mimic chronic spinal cord injury.These findings collectively show promising evidence for a combinatorial strategy with chondroitinase ABC and Schwann cells in promoting remodeling and recovery of function following spinal cord injury. 展开更多
关键词 axonal regrowth bladder function chondroitinase ABC functional recovery glial scar LENTIVIRUS migration Schwann cell spinal cord injury TRANSPLANTATION
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Beyond Defense: Proactive Approaches to Disaster Recovery and Threat Intelligence in Modern Enterprises
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作者 Meysam Tahmasebi 《Journal of Information Security》 2024年第2期106-133,共28页
As cyber threats keep changing and business environments adapt, a comprehensive approach to disaster recovery involves more than just defensive measures. This research delves deep into the strategies required to respo... As cyber threats keep changing and business environments adapt, a comprehensive approach to disaster recovery involves more than just defensive measures. This research delves deep into the strategies required to respond to threats and anticipate and mitigate them proactively. Beginning with understanding the critical need for a layered defense and the intricacies of the attacker’s journey, the research offers insights into specialized defense techniques, emphasizing the importance of timely and strategic responses during incidents. Risk management is brought to the forefront, underscoring businesses’ need to adopt mature risk assessment practices and understand the potential risk impact areas. Additionally, the value of threat intelligence is explored, shedding light on the importance of active engagement within sharing communities and the vigilant observation of adversary motivations. “Beyond Defense: Proactive Approaches to Disaster Recovery and Threat Intelligence in Modern Enterprises” is a comprehensive guide for organizations aiming to fortify their cybersecurity posture, marrying best practices in proactive and reactive measures in the ever-challenging digital realm. 展开更多
关键词 Advanced Persistent Threats (APT) Attack Phases Attack Surface DEFENSE-IN-DEPTH disaster recovery (dr) Incident Response Plan (IRP) Intrusion Detection Systems (IDS) Intrusion Prevention System (IPS) Key Risk Indicator (KRI) Layered Defense Lockheed Martin Kill Chain Proactive Defense Redundancy Risk Management Threat Intelligence
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Risk assessment of coastal flooding disaster by storm surge based on Elevation-Area method and hydrodynamic models:Taking Bohai Bay as an example
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作者 Fu Wang Xue-zheng Liu +3 位作者 Yong Li Heng Yu Ming-zheng Wen Yun-zhuang Hu 《China Geology》 CAS CSCD 2024年第3期494-504,共11页
The future inundation by storm surge on coastal areas are currently ill-defined.With increasing global sealevel due to climate change,the coastal flooding by storm surge is more and more frequently,especially in coast... The future inundation by storm surge on coastal areas are currently ill-defined.With increasing global sealevel due to climate change,the coastal flooding by storm surge is more and more frequently,especially in coastal lowland with land subsidence.Therefore,the risk assessment of such inundation for these areas is of great significance for the sustainable socio-economic development.In this paper,the authors use Elevation-Area method and Regional Ocean Model System(ROMS)model to assess the risk of the inundation of Bohai Bay by storm surge.The simulation results of Elevation-Area method show that either a 50-year or 100-year storm surge can inundate coastal areas exceeding 8000 km^(2);the numerical simulation results based on hydrodynamics,considering ground friction and duration of the storm surge high water,show that a 50-year or 100-year storm surge can only inundate an area of over 2000 km^(2),which is far less than 8000 km^(2);while,when taking into account the land subsidence and sea level rise,the very inundation range will rapidly increase by 2050 and 2100.The storm surge will greatly impact the coastal area within about 10-30 km of the Bohai Bay,in where almost all major coastal projects are located.The prompt response to flood disaster due to storm surge is urgently needed,for which five suggestions have been proposed based on the geological background of Bohai Bay.This study may offer insight into the development of the response and adaptive plans for flooding disasters caused by storm surge. 展开更多
关键词 Storm surge ROMS Elevation-Area method Numerical simulation Land subsidence Flooding disaster Sea level rise Marine geological survey engineering Geological disaster survey engineering Bohai Bay
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Hydrometallurgical process and recovery of valuable elements for limonitic laterite:A review
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作者 Xinglong Xiong Baozhong Ma +4 位作者 Xiang Li Jiancheng Yu Longfei Shi Chengyan Wang Yongqiang Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期189-201,共13页
Nickel is a strategic resource in social life and defense technology,playing an essential role in many fields,such as alloys and batteries.With the decrease in nickel sulfide,it is of great significance to extract nic... Nickel is a strategic resource in social life and defense technology,playing an essential role in many fields,such as alloys and batteries.With the decrease in nickel sulfide,it is of great significance to extract nickel from laterite.The limonitic laterite is a kind of rich nickel-cobalt-scandium resource.At present,there are few reviews on the extraction of limonitic laterite.This study reviews the hydrometallurgical processes for limonitic laterite ores and the methods of recovering valuable elements.The mineralogical characteristics are analyzed,and the typical mineral compositions are summarized.The main hydrometallurgical processes are compared and discussed,including reduction roasting-ammonia leaching,sulfuric acid pressure leaching,nitric acid pressure leaching,and the atmospheric nitric acid leaching(DNi process).The methods of recovering nickel,cobalt,scandium,and iron are emphatically outlined.Finally,reasonable suggestions are proposed for comprehensive utilization.This study can provide a reference for industrial development and diversified applications. 展开更多
关键词 Limonitic laterite HYdrOMETALLURGY Comprehensive utilization LEACHING recovery Chemical processes
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Analysis of Factors Associated with the Abandonment of Nutritional Recovery among Parents of Severely Malnourished Children Aged 6 to 59 Months in the Health District of Titao, Burkina Faso
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作者 Aminata Gansore Patrice Ngangue +7 位作者 Birama Apho Ly Ludovic K. N’Tcha Douglas Mbang Massom Gbètogo Maxime Kiki Josiane Seu Nestor Bationo Noufou Gustave Nana Fla Koueta 《Open Journal of Nursing》 2024年第9期477-490,共14页
Introduction: In Burkina Faso, undernutrition is a public health problem associated with more than 40% of infant and child mortality. Undernutrition management is complex, and there is often a risk of treatment abando... Introduction: In Burkina Faso, undernutrition is a public health problem associated with more than 40% of infant and child mortality. Undernutrition management is complex, and there is often a risk of treatment abandonment. Studies on this topic have not explored the influence of environmental and therapeutic factors on parental compliance. This study proposes an analysis of factors influencing the abandonment of nutritional recovery by parents of malnourished children aged 6 to 59 months in ambulatory care. Methods: This was a descriptive and exploratory qualitative study. Data collection took place in February 2020. Data were collected from seventeen (17) participants via in-depth interviews (IDI) and direct observation. The IDIs were transcribed verbatim and thematically analyzed using Nvivo software. Results: The results revealed that factors related to the physical environment, such as geographical inaccessibility, pastoral occupation, displacement at auriferous sites, and insecurity, are important causes of nutritional recovery abandonment. They also prove that factors related to the social environment, such as lack of family and social support, feelings of shame, stigmatization, occupation of the mother, and social events, lead to this abandonment. In addition, therapeutic factors such as interruptions of supplies of Ready to Use Therapeutic Food (RUTF), feeling of improvement or worsening of the state of health, recourse to traditional medicine, and ignorance of undernutrition are also associated with this issue. Conclusion: This study highlighted barriers to the abandonment of nutritional recovery among parents of severely malnourished children aged 6 to 59 months in the health district of Titao, Burkina Faso. It is more important to consider these different factors when evaluating care protocols so that policies to reduce child undernutrition can considerably impact the targets. 展开更多
关键词 Nutritional recovery Severe Acute Malnutrition Environmental Factors Therapeutic Factors ABANDONMENT Burkina Faso
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Deterministic tools to predict gas assisted gravity drainage recovery factor
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作者 Maryam Hasanzadeh Mohammad Madani 《Energy Geoscience》 EI 2024年第3期24-38,共15页
Naturally fractured rocks contain most of the world's petroleum reserves.This significant amount of oil can be recovered efficiently by gas assisted gravity drainage(GAGD).Although,GAGD is known as one of the most... Naturally fractured rocks contain most of the world's petroleum reserves.This significant amount of oil can be recovered efficiently by gas assisted gravity drainage(GAGD).Although,GAGD is known as one of the most effective recovery methods in reservoir engineering,the lack of available simulation and mathematical models is considerable in these kinds of reservoirs.The main goal of this study is to provide efficient and accurate methods for predicting the GAGD recovery factor using data driven techniques.The proposed models are developed to relate GAGD recovery factor to the various parameters including model height,matrix porosity and permeability,fracture porosity and permeability,dip angle,viscosity and density of wet and non-wet phases,injection rate,and production time.In this investigation,by considering the effective parameters on GAGD recovery factor,three different efficient,smart,and fast models including artificial neural network(ANN),least square support vector machine(LSSVM),and multi-gene genetic programming(MGGP)are developed and compared in both fractured and homogenous porous media.Buckinghamπtheorem is also used to generate dimensionless numbers to reduce the number of input and output parameters.The efficiency of the proposed models is examined through statistical analysis of R-squared,RMSE,MSE,ARE,and AARE.Moreover,the performance of the generated MGGP correlation is compared to the traditional models.Results demonstrate that the ANN model predicts the GAGD recovery factor more accurately than the LSSVM and MGGP models.The maximum R^(2)of 0.9677 and minimum RMSE of 0.0520 values are obtained by the ANN model.Although the MGGP model has the lowest performance among the other used models(the R2 of 0.896 and the RMSE of 0.0846),the proposed MGGP correlation can predict the GAGD recovery factor in fractured and homogenous reservoirs with high accuracy and reliability compared to the traditional models.Results reveal that the employed models can easily predict GAGD recovery factor without requiring complicate governing equations or running complex and time-consuming simulation models.The approach of this research work improves our understanding about the most significant parameters on GAGD recovery and helps to optimize the stages of the process,and make appropriate economic decisions. 展开更多
关键词 Gas assisted gravity drainage recovery factor Deterministic tools Statistical evaluation
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Disaster Risk Reduction (DRR) Education from Social Disciplinary Theoretical Perspectives
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作者 Yagya Raj Pant 《Open Journal of Earthquake Research》 2024年第1期41-83,共43页
Disaster is a social phenomenon. The occurrence and impacts of disasters including the education sector can be studied through a social problem lens. This paper draws meaning and understanding of DRR education using t... Disaster is a social phenomenon. The occurrence and impacts of disasters including the education sector can be studied through a social problem lens. This paper draws meaning and understanding of DRR education using the sociological disciplinary framework in a detailed qualitative case study of three schools as they responded to the devastating Gorakha earthquake in 2015 and other disasters in Nepal. This paper considers the three sub-disciplines of sociology: the sociology of disaster, the sociology of education and the sociology of education governance in a development context. These sub-disciplines are nested together to analyse social, political and historical factors and their relationships which are helpful to identify risks and vulnerabilities in the education sector in Nepal. These are the major areas to explore the disaster context and needs of context-specific education acts (hereafter DRR education) to minimise the potential risks of disasters. The article concludes that the social disciplinary framework is significantly useful to analyse DRR education provisions and implications of education governance to mobilise school in disaster preparedness, response and recovery. 展开更多
关键词 Sociology of disaster Social Vulnerability disaster Governance Education Governance disaster Risk Reduction (drR) Education Pluri-Scalar Education Governance
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Regression analysis and its application to oil and gas exploration:A case study of hydrocarbon loss recovery and porosity prediction,China
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作者 Yang Li Xiaoguang Li +3 位作者 Mingyu Guo Chang Chen Pengbo Ni Zijian Huang 《Energy Geoscience》 EI 2024年第4期240-252,共13页
In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not... In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not just at predicting geophysical logging curve values but also innovatively mitigate hydrocarbon depletion observed in geochemical logging.Through a rigorous assessment,we explore the efficacy of eight regression models,bifurcated into linear and nonlinear groups,to accommodate the multifaceted nature of geological datasets.Our linear model suite encompasses the Standard Equation,Ridge Regression,Least Absolute Shrinkage and Selection Operator,and Elastic Net,each presenting distinct advantages.The Standard Equation serves as a foundational benchmark,whereas Ridge Regression implements penalty terms to counteract overfitting,thus bolstering model robustness in the presence of multicollinearity.The Least Absolute Shrinkage and Selection Operator for variable selection functions to streamline models,enhancing their interpretability,while Elastic Net amalgamates the merits of Ridge Regression and Least Absolute Shrinkage and Selection Operator,offering a harmonized solution to model complexity and comprehensibility.On the nonlinear front,Gradient Descent,Kernel Ridge Regression,Support Vector Regression,and Piecewise Function-Fitting methods introduce innovative approaches.Gradient Descent assures computational efficiency in optimizing solutions,Kernel Ridge Regression leverages the kernel trick to navigate nonlinear patterns,and Support Vector Regression is proficient in forecasting extremities,pivotal for exploration risk assessment.The Piecewise Function-Fitting approach,tailored for geological data,facilitates adaptable modeling of variable interrelations,accommodating abrupt data trend shifts.Our analysis identifies Ridge Regression,particularly when augmented by Piecewise Function-Fitting,as superior in recouping hydrocarbon losses,and underscoring its utility in resource quantification refinement.Meanwhile,Kernel Ridge Regression emerges as a noteworthy strategy in ameliorating porosity-logging curve prediction for well A,evidencing its aptness for intricate geological structures.This research attests to the scientific ascendancy and broad-spectrum relevance of these regression techniques over conventional methods while heralding new horizons for their deployment in the oil and gas sector.The insights garnered from these advanced modeling strategies are set to transform geological and engineering practices in hydrocarbon prediction,evaluation,and recovery. 展开更多
关键词 Regression analysis Oil and gas exploration Multiple linear regression model Nonlinear regression model Hydrocarbon loss recovery Porosity prediction
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Analyzing Disaster Mitigation Policies in Japan and China from an Eco-DRR Perspective:A Comparative Study of Shanghai and Tokyo
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作者 Minghui Tang Naoko Fujita 《Journal of Architectural Research and Development》 2024年第1期14-19,共6页
Global climate change-induced natural disasters require international efforts and the adoption of Eco-Disaster Risk Reduction(Eco-DRR)policies for sustainable development.This study examines the status of Eco-DRR in d... Global climate change-induced natural disasters require international efforts and the adoption of Eco-Disaster Risk Reduction(Eco-DRR)policies for sustainable development.This study examines the status of Eco-DRR in disaster prevention policies through word cloud analysis,providing insights for policymakers to enhance disaster prevention amid increasing climate-related challenges.Tokyo and Japan prioritize soft aspects,while Shanghai and China emphasize engineering for flood prevention,revealing a gap in Eco-DRR application.Despite these differing approaches,the shared focus on water-related disasters indicates a shift towards urban resilience.Future research should assess policy effectiveness and the impact of Eco-DRR on disaster risk reduction and ecosystem protection. 展开更多
关键词 disaster Policy Eco-drR Word-cloud
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Forecast future disasters using hydro-meteorological datasets in the Yamuna river basin,Western Himalaya:Using Markov Chain and LSTM approaches
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作者 Pankaj Chauhan Muhammed Ernur Akiner +1 位作者 Rajib Shaw Kalachand Sain 《Artificial Intelligence in Geosciences》 2024年第1期114-136,共23页
This research aim to evaluate hydro-meteorological data from the Yamuna River Basin,Uttarakhand,India,utilizing Extreme Value Distribution of Frequency Analysis and the Markov Chain Approach.This method assesses persi... This research aim to evaluate hydro-meteorological data from the Yamuna River Basin,Uttarakhand,India,utilizing Extreme Value Distribution of Frequency Analysis and the Markov Chain Approach.This method assesses persistence and allows for combinatorial probability estimations such as initial and transitional probabilities.The hydrologic data was generated(in-situ)and received from Uttarakhand Jal Vidut Nigam Limited(UJVNL),and meteorological data was acquired from NASA’s archives MERRA-2 product.A total of sixteen years(2005-2020)of data was used to foresee daily Precipitation from 2020 to 2022.MERRA-2 products are utilized as observed and forecast values for daily Precipitation throughout the monsoon season,which runs from July to September.Markov Chain and Long Short-Term Memory(LSTM)findings for 2020,2021,and 2022 were observed,and anticipated values for daily rainfall during the monsoon season between July and September.According to test findings,the artificial intelligence technique cannot anticipate future regional meteorological formations;the correlation coefficient R^(2) is around 0.12.According to the randomly verified precipitation data findings,the Markov Chain model has a success rate of 79.17 percent.The results suggest that extended return periods should be a warning sign for drought and flood risk in the Himalayan region.This study gives a better knowledge of the water budget,climate change variability,and impact of global warming,ultimately leading to improved water resource management and better emergency planning to the establishment of the Early Warning System(EWS)for extreme occurrences such as cloudbursts,flash floods,landslides hazards in the complex Himalayan region. 展开更多
关键词 Forecast disasters Western Himalaya Hydro-meteorological hazards LSTM Markov chain Yamuna river basin
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Intestinal Microecology in Children with Pneumonia: The Relationship Between Digestive Health and Disease Recovery
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作者 Weina Song Shuyan Zhang +3 位作者 Zhaorui Wang Fanyan Meng Ben Wang Ning Yang 《Journal of Clinical and Nursing Research》 2024年第6期15-20,共6页
This paper explores the association between intestinal microecology and digestive health and disease recovery in children with pneumonia.Intestinal microecological imbalance is common in children with pneumonia,which ... This paper explores the association between intestinal microecology and digestive health and disease recovery in children with pneumonia.Intestinal microecological imbalance is common in children with pneumonia,which is closely associated with digestive health and disease recovery.Intestinal microecological imbalance may affect digestive enzyme activity,intestinal mucosal barrier function,and nutrient absorption,which in turn affects digestive health.In addition,intestinal microecological imbalances may be associated with immune regulation,inflammatory responses,and pathogen suppression,affecting disease recovery.Strategies to regulate intestinal microecology include probiotic supplementation,dietary modification,and pharmacological treatment.Currently,the study of intestinal microecology in children with pneumonia faces challenges,and there is a need for improved research methods,individualized treatment strategies,and the development of novel probiotics.In conclusion,the intestinal microecology of children with pneumonia is closely related to digestive health and disease recovery,and the regulation of intestinal microecology is of great significance to the treatment of children with pneumonia.Furthermore,future research should further explore the application of the microecology of the intestinal microecology in the treatment of children with pneumonia. 展开更多
关键词 Children with pneumonia Intestinal microecology Digestive health Disease recovery PROBIOTICS IMMUNOMODULATION
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Pharmacological targeting cGAS/STING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury
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作者 Ziwei Fan Mengxian Jia +16 位作者 Jian Zhou Zhoule Zhu Yumin Wu Xiaowu Lin Yiming Qian Jiashu Lian Xin Hua Jianhong Dong Zheyu Fang Yuqing Liu Sibing Chen Xiumin Xue Juanqing Yue Minyu Zhu Ying Wang Zhihui Huang Honglin Teng 《Neural Regeneration Research》 SCIE CAS 2025年第11期3287-3301,共15页
The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord injury.Regulation of shifting microglia ... The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord injury.Regulation of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be crucial.Tryptanthrin possesses an anti-inflammatory biological function.However,its roles and the underlying molecular mechanisms in spinal cord injury remain unknown.In this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in vitro.Tryptanthrin promoted M2 polarization through inactivating the cGAS/STING/NF-κB pathway.Additionally,we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord injury.Finally,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal apoptosis.Taken together,these results suggest that by targeting the cGAS/STING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype. 展开更多
关键词 cGAS/STING functional recovery MICROGLIA neuroinflammation neuroprotection nuclear factor-κB POLARIZATION spinal cord injury TRYPTANTHRIN
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Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex
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作者 Yan Li Peng Hao +6 位作者 Hongmei Duan Fei Hao Wen Zhao Yudan Gao Zhaoyang Yang Kwok-Fai So Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第10期2923-2937,共15页
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne... The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries. 展开更多
关键词 adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation
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Recovery of alumina from circulating fluidized bed combustion Al-rich fly ash using mild hydrochemical process 被引量:16
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作者 杨权成 马淑花 +1 位作者 郑诗礼 张然 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1187-1195,共9页
To utilize CFBC Al-rich fly ash, a mild hydrochemical extraction process was investigated for recovery of alumina. An alumina extraction efficiency of 92.31%was attained using a 45%NaOH solution, an original caustic r... To utilize CFBC Al-rich fly ash, a mild hydrochemical extraction process was investigated for recovery of alumina. An alumina extraction efficiency of 92.31%was attained using a 45%NaOH solution, an original caustic ratio (molar ratio of Na2O to Al2O3 in the sodium aluminate solution) of 25, a molar ratio of CaO to SiO2 in the fly ash of 1.1, a liquid volume to solid mass ratio of 9, a reaction temperature of 280 ℃, and a residence time of 1 h when treating fly ash with an alumina to silica mass ratio (A/S) of 0.78 and an alumina content of 32.43%. Additionally, the alumina leaching mechanism was explored via structural and chemical analysis, which revealed that after alkaline digestion, the main solid phase containing silica was NaCaHSiO4 with a theoretical A/S of zero. 展开更多
关键词 recovery of alumina fly ash phase transformation circulating fluidized bed combustion (CFBC)
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Recovery of titanium from undissolved residue(tionite) in titanium oxide industry via NaOH hydrothermal conversion and H_2SO_4 leaching 被引量:3
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作者 孟凡成 薛天艳 +2 位作者 刘亚辉 张国之 齐涛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第6期1696-1705,共10页
To recover titanium from tionite, a new process consisting of NaOH hydrothermal conversion, water washing, and H2SO4 leaching for TiO2 preparation was developed. The experimental results show that under the optimum ... To recover titanium from tionite, a new process consisting of NaOH hydrothermal conversion, water washing, and H2SO4 leaching for TiO2 preparation was developed. The experimental results show that under the optimum hydrothermal conversion conditions, i.e., 50% NaOH (mass fraction) solution, NaOH/tionite mass ratio of 4:1, reaction temperature of 240 ℃reaction time of 1 h and oxygen partial pressure of 0.25 MPa, the titanium was mainly converted into Na2TiO3, and the conversion was 97.2%. The unwanted product Na2TiSiO5 remained stable in water washing, and its formation was prevented by improving NaOH concentration. In water washing process, about 97.6% of Na+ could be recycled by washing the hydrothermal product. The NaOH solutions could be reused after concentration. 96.7% of titanium in the washed product was easily leached in H2SO4 solution at low temperatures, forming titanyl sulfate solution to further prepare TiO2. 展开更多
关键词 tionite titanium recovery NaOH hydrothermal conversion water washing H2SO4 leaching
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Review on Drought Disasters in the Five Provinces of Northern China in 1920
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作者 王鑫宏 《Meteorological and Environmental Research》 CAS 2010年第4期87-91,共5页
This paper analyzed the severe drought that took place in the five provinces of Northern China in 1920.Study suggested that the severe damage caused by the drought was resulted from many reasons,such as certain specif... This paper analyzed the severe drought that took place in the five provinces of Northern China in 1920.Study suggested that the severe damage caused by the drought was resulted from many reasons,such as certain specific natural conditions,deterioration of ecological environment,malformations of the rural economy and turbulence of domestic politics.However,some new phenomena took shapes during this time disaster relief activity. 展开更多
关键词 1920 Five provinces in northern China drOUGHT Characteristics Cause of formation disaster relief China
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Robust Disaster Recovery System Model 被引量:2
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作者 WANG Kun SU Rui-dan +2 位作者 LI Zeng-xin CAI Zhen ZHOU Li-hua 《Wuhan University Journal of Natural Sciences》 CAS 2006年第1期170-174,共5页
Highly security-critical system should possess features of continuous service. We present a new Robust Disaster Recovery System Model (RDRSM). Through strengthening the ability of safe communications, RDRSM guarante... Highly security-critical system should possess features of continuous service. We present a new Robust Disaster Recovery System Model (RDRSM). Through strengthening the ability of safe communications, RDRSM guarantees the secure and reliable command on disaster recovery. Its self-supervision capability can monitor the integrality and security of disaster recovery system itself. By 2D and 3D rea-time visible platform provided by GIS, GPS and RS, the model makes the using, management and maintenance of disaster recovery system easier. RDRSM possesses predominant features of security, robustness and controllability. And it can be applied to highly security-critical environments such as E-government and bank. Conducted by RDRSM, an important E-government disaster recovery system has been constructed successfully. The feasibility of this model is verified by practice. We especially emphasize the significance of some components of the model, such as risk assessment, disaster recovery planning, system supervision and robust communication support. 展开更多
关键词 continuous service E-GOVERNMENT information security disaster recovery high availability risk assessment data backup
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Phosphate removal and recovery through crystallization of hydroxyapatite using xonotlite as seed crystal 被引量:25
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作者 CHEN Xuechu, KONG Hainan, WU Deyi, WANG Xinze, LIN Yongyong School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期575-580,共6页
Xonotlite was synthesized and tested for phosphate removal and recovery from synthetic solution in a batch mode. The effects of pH, initial calcium concentration, bicarbonate concentration on phosphate removal through... Xonotlite was synthesized and tested for phosphate removal and recovery from synthetic solution in a batch mode. The effects of pH, initial calcium concentration, bicarbonate concentration on phosphate removal through crystallization were examined. The morphology and X-ray diffraction (XRD) pattern of xonotlite before and after crystallization confirmed the formation of crystalline hydroxyapatite. The results indicated that the crystallization product had a very high P content (〉 10%), which is comparable to phosphate rock at the dosage of 50-200 mg xonotlite per liter, with a maximum P content of 16.7%. The kinetics of phosphate removal followed the second-order reaction equation. The phosphate removal ability increased with increasing pH. The precipitation of calcium phosphate took place when pH was higher than 7.2, whereas the crystallization occurred at pH 6.0. A high calcium concentration could promote the removal of phosphate via crystallization, while a high bicarbonate concentration also enhanced phosphate removal, through that the pH was increased and thus induced the precipitation process. When xonotlite was used to remove phosphate from wastewater, the removal efficiency could reach 91.3% after 24 h reaction, with removal capacity 137 mg/g. The results indicated that xonotlite might be used as an effective crystal seed for the removal and recovery of phosphate from aqueous solution. 展开更多
关键词 PHOSPHATE recovery CRYSTALLIZATION XONOTLITE
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A review: Enhanced recovery of natural gas hydrate reservoirs 被引量:8
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作者 Fengguang Li Qing Yuan +3 位作者 Tianduo Li Zhi Li Changyu Sun Guangjin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第9期2062-2073,共12页
Natural gas hydrate(NGH)is a highly efficient and clean energy,with huge reserves and widespread distribution in permafrost and marine areas.Researches all over the world are committed to developing an effective explo... Natural gas hydrate(NGH)is a highly efficient and clean energy,with huge reserves and widespread distribution in permafrost and marine areas.Researches all over the world are committed to developing an effective exploring technology for NGH reservoirs.In this paper,four conventional in-situ hydrate production methods,such as depressurization,thermal stimulation,inhibitor injection and CO2 replacement,are briefly introduced.Due to the limitations of each method,there has been no significantly breakthrough in hydrate exploring technology.Inspired by the development of unconventional oil and gas fields,researchers have put forward some new hydrate production methods.We summarize the enhanced hydrate exploiting methods,such as CO2/N2–CH4 replacement,CO2/H2–CH4 replacement,hydraulic fracturing treatment,and solid exploration;and potential hydrate mining techniques,such as self-generating heat fluid injection,geothermal stimulation,the well pattern optimization of hydrate exploring.The importance of reservoir stimulation technology for hydrate exploitation is emphasized,and it is believed that hydrate reservoir modification technology is a key to open hydrate resources exploitation,and the major challenges in the process of hydrate exploitation are pointed out.The combination of multiple hydrate exploring technologies and their complementary advantages will be the development trend in the future so as to promote the process of hydrate industrialization. 展开更多
关键词 HYdrATE Exploration/exploitation recovery Production STIMULATION technology
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Historical drought and water disasters in the Weihe Plain 被引量:8
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作者 YINShuyan HUANGChunchang LIXinyan 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期97-105,共9页
Through detailed statistics and analysis of drought and water disasters in the Weihe Plain in the historical period, we discovered that in more than 2300 years (from 370 BC to 2000 AD), natural disasters occurred most... Through detailed statistics and analysis of drought and water disasters in the Weihe Plain in the historical period, we discovered that in more than 2300 years (from 370 BC to 2000 AD), natural disasters occurred most frequently in two periods. One is from 610 to 850 AD (from the late Sui Dynasty to the late Tang Dynasty) and the other is from 1580 to 2000 AD (after the late Ming Dynasty). Different natural disasters occurred synchronously, that is to say, when the drought occurred frequently, water disasters occurred frequently in the same periods. Frequencies of natural disasters, on the one hand, connected with climate changes and development course of ancient cities, while on the other, related closely to population changes. The excessive exploitation of natural resources and human disturbance and damages to ecological environment are the major reasons for the increased drought and water disasters. 展开更多
关键词 natural disasters ancient city human impact the Weihe Plain
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