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Post-acute ischemic stroke hyperglycemia aggravates destruction of the blood-brain barrier 被引量:1
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作者 Tianqi Xu Jianhong Yang +5 位作者 Yao Xu xiaofeng wang Xiang Gao Jie Sun Chenhui Zhou Yi Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1344-1350,共7页
Post-acute ischemic stroke hyperglycemia increases the risk of hemorrhagic transformation,which is associated with blood-brain barrier disruption.Brain microvascular endothelial cells are a major component of the bloo... Post-acute ischemic stroke hyperglycemia increases the risk of hemorrhagic transformation,which is associated with blood-brain barrier disruption.Brain microvascular endothelial cells are a major component of the blood-brain barrier.Intercellular mitochondrial transfer has emerged as a novel paradigm for repairing cells with mitochondrial dysfunction.In this study,we first investigated whether mitochondrial transfer exists between brain microvascular endothelial cells,and then investigated the effects of post-acute ischemic stroke hyperglycemia on mitochondrial transfer between brain microvascular endothelial cells.We found that healthy brain microvascular endothelial cells can transfer intact mitochondria to oxygen glucose deprivation-injured brain microvascular endothelial cells.However,post-oxygen glucose deprivation hyperglycemia hindered mitochondrial transfer and exacerbated mitochondrial dysfunction.We established an in vitro brain microvascular endothelial cell model of the blood-brain barrier.We found that post-acute ischemic stroke hyperglycemia reduced the overall energy metabolism levels of brain microvascular endothelial cells and increased permeability of the blood-brain barrier.In a clinical study,we retrospectively analyzed the relationship between post-acute ischemic stroke hyperglycemia and the severity of hemorrhagic transformation.We found that post-acute ischemic stroke hyperglycemia serves as an independent predictor of severe hemorrhagic transformation.These findings suggest that post-acute ischemic stroke hyperglycemia can aggravate disruption of the blood-brain barrier by inhibiting mitochondrial transfer. 展开更多
关键词 acute ischemic stroke blood-brain barrier brain microvascular endothelial cells mitochondrial transfer stress hyperglycemia
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A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM
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作者 Yili wang Changsheng Li xiaofeng wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期463-474,共12页
When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ... When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of layers.To address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent network.By leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration process.The analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,respectively.The model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target plates.The maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed model.Moreover,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves. 展开更多
关键词 Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion
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Perpendicular-Cutdepth:Perpendicular Direction Depth Cutting Data Augmentation Method
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作者 Le Zou Linsong Hu +2 位作者 Yifan wang Zhize Wu xiaofeng wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期927-941,共15页
Depth estimation is an important task in computer vision.Collecting data at scale for monocular depth estimation is challenging,as this task requires simultaneously capturing RGB images and depth information.Therefore... Depth estimation is an important task in computer vision.Collecting data at scale for monocular depth estimation is challenging,as this task requires simultaneously capturing RGB images and depth information.Therefore,data augmentation is crucial for this task.Existing data augmentationmethods often employ pixel-wise transformations,whichmay inadvertently disrupt edge features.In this paper,we propose a data augmentationmethod formonocular depth estimation,which we refer to as the Perpendicular-Cutdepth method.This method involves cutting realworld depth maps along perpendicular directions and pasting them onto input images,thereby diversifying the data without compromising edge features.To validate the effectiveness of the algorithm,we compared it with existing convolutional neural network(CNN)against the current mainstream data augmentation algorithms.Additionally,to verify the algorithm’s applicability to Transformer networks,we designed an encoder-decoder network structure based on Transformer to assess the generalization of our proposed algorithm.Experimental results demonstrate that,in the field of monocular depth estimation,our proposed method,Perpendicular-Cutdepth,outperforms traditional data augmentationmethods.On the indoor dataset NYU,our method increases accuracy from0.900 to 0.907 and reduces the error rate from0.357 to 0.351.On the outdoor dataset KITTI,our method improves accuracy from 0.9638 to 0.9642 and decreases the error rate from 0.060 to 0.0598. 展开更多
关键词 PERPENDICULAR depth estimation data augmentation
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具有定向电荷传递能力的晶态线型聚酰亚胺材料驱动光催化CO_(2)还原
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作者 李慧珍 陈艳蕾 +5 位作者 牛青 王小凤 刘哲源 毕进红 于岩 李留义 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第6期152-159,共8页
利用太阳能和半导体催化材料将CO_(2)还原为具有高附加值的含碳化学品为解决能源危机等问题提供了一个有前景的解决方案.目前半导体光催化CO_(2)还原的效率仍然很低,这主要是光激发的载流子复合严重等问题导致的.探索有效策略来增强半... 利用太阳能和半导体催化材料将CO_(2)还原为具有高附加值的含碳化学品为解决能源危机等问题提供了一个有前景的解决方案.目前半导体光催化CO_(2)还原的效率仍然很低,这主要是光激发的载流子复合严重等问题导致的.探索有效策略来增强半导体光催化材料光生电荷分离和传输性能被认为是提高CO_(2)还原效率的关键之一.设计制备具有定向电荷传输性能的光催化材料将有助于抑制光生电荷复合,从而实现高效光催化性能.线型共轭有机聚合物具有直链状结构、明晰和多样的元素组成、良好的水热稳定性等优点在光催化领域受到持续的关注和研究.本文通过均苯四甲酸二酐和二胺单体的缩合反应制备了三例晶态线型共轭聚酰亚胺材料用于光催化CO_(2)还原.利用粉末X射线衍射、傅里叶红外光谱、扫描电子显微镜、透射电子显微镜、紫外可见吸收光谱和气体吸附测试等对合成的聚酰亚胺的晶态结构、光吸收性质、形貌结构和孔结构等进行了表征.利用光电化学、电子顺磁共振波普分析、电位分析和密度泛函理论计算等研究了构筑单元的电子推拉效应对聚合物电荷分离及催化性能的影响.结果表明,三种结晶型聚酰亚胺均对CO_(2)具有良好的吸附能力且满足光催化CO_(2)还原电势的能带结构要求.光生载流子的复合程度随着重复结构单元偶极距的增强而降低,其中基于苯并噻吩砜的晶态线型聚酰亚胺(CLP-CS)具有最优的载流子分离能力.在光催化CO_(2)还原反应中,CLP-CS表现出高达1700μmol h-1gcat-1的CO析出效率和90%的选择性.CLP-CS在高低温和紫外灯照射等极端条件下,仍保持良好的结构稳定性和催化活性.实验发现,聚合物的CO_(2)还原活性与重复结构单元的偶极距及方向密切有关.局部结构的不对称性,扩大了分子偶极,增强了材料的内建电场驱动力.此外,长程有序的线型结构为光生电荷传输提供了快速迁移通道,促进了载流子迁移.综上,本文报道了基于晶态线型聚合物的光催化体系,为实现光生电荷定向传输和开发高效光催化材料提供了途径. 展开更多
关键词 光催化 结晶聚合物 聚酰亚胺 二氧化碳还原 电子定向转移
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早期非小细胞肺癌患者立体定向放射治疗的预后分析 被引量:1
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作者 余璐 李俊毅 +4 位作者 高苗苗 王小凤 柏慧 关勇 袁智勇 《中国肺癌杂志》 CAS CSCD 北大核心 2023年第4期274-280,共7页
背景与目的随着人口老龄化和肺癌筛查受重视程度的提高,近年来早期肺癌就诊量呈上升趋势。其病理类型以非小细胞肺癌(non-small cell lung cancer,NSCLC)为主,可被划分为可手术早期肺癌和不可手术早期肺癌。立体定向放射治疗(stereotact... 背景与目的随着人口老龄化和肺癌筛查受重视程度的提高,近年来早期肺癌就诊量呈上升趋势。其病理类型以非小细胞肺癌(non-small cell lung cancer,NSCLC)为主,可被划分为可手术早期肺癌和不可手术早期肺癌。立体定向放射治疗(stereotactic body radiation therapy,SBRT)是不可手术早期NSCLC的首选治疗方法。本研究旨在探讨我院早期NSCLC患者行SBRT后的预后及其影响因素,以期提高早期NSCLC患者接受SBRT后的生存期。方法收集2010年8月-2020年8月在我院接受SBRT的早期NSCLC患者的临床资料及随访情况,采用Kaplan-Meier法评估预后,采用Cox比例风险模型进行多因素分析寻找影响预后的因素。结果共纳入165例患者,中位随访时间为43.2(范围:4.8-132.1)个月。1年、2年、5年局部控制(local control,LC)率分别为98.1%、94.8%和86.5%,卡氏功能状态评分(Karnofsky performance status,KPS)>80分是LC的独立预后因素(P=0.02);1年、2年、5年总生存(overall survival,OS)率分别为97.6%、93.0%和68.9%,生物等效剂量(biological equivalent dose whenα/β=10,BED_(10))>132 Gy是OS的独立预后因素(P=0.04);1年、2年、5年无进展生存(progression-free survival,PFS)率分别为93.3%、79.5%和55.3%;1年、2年、5年无远处转移生存(distance metastasis free survival,DMFS)率分别为94.5%、83.2%和58.4%,BED_(10)>150 Gy是DMFS的独立预后因素(P=0.02);1年、2年、5年区域控制(region control,RC)率分别为98.8%、95.4%和87.9%。结论SBRT治疗早期NSCLC疗效好,KPS>80分是影响LC的独立预后因素;BED_(10)>132Gy是OS的独立预后因素;BED_(10)>150 Gy是DMFS的独立预后因素。 展开更多
关键词 肺肿瘤 立体定向放射治疗 预后
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Prognostic-related genes for pancreatic cancer typing and immunotherapy response prediction based on single-cell sequencing data and bulk sequencing data
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作者 XUEFENG wang SICONG JIANG +3 位作者 XINHONG ZHOU xiaofeng wang LAN LI JIANJUN TANG 《Oncology Research》 SCIE 2023年第5期697-714,共18页
Pancreatic cancer is associated with high mortality and is one of the most aggressive of malignancies,but studies have not fully evaluated its molecular subtypes,prognosis and response to immunotherapy of different su... Pancreatic cancer is associated with high mortality and is one of the most aggressive of malignancies,but studies have not fully evaluated its molecular subtypes,prognosis and response to immunotherapy of different subtypes.The purpose of this study was to explore the molecular subtypes and the key genes associated with the prognosis of pancreas cancer patients and study the clinical phenotype,prognosis and response to immunotherapy using single-cell seq data and bulk RNA seq data,and data retrieved from GEO and TCGA databases.Methods:Single-cell seq data and bioinformatics methods were used in this study.Pancreatic cancer data were retrieved from GEO and TCGA databases,the molecular subtypes of pancreatic cancer were determined using the six cGAS-STING related pathways,and the clinical phenotype,mutation,immunological characteristics and pathways related to pancreatic cancer were evaluated.Results:Pancreatic cancer was classified into 3 molecular subtypes,and survival analysis revealed that patients in Cluster3(C3)had the worst prognosis,whereas Cluster1(C1)had the best prognosis.The clinical phenotype and gene mutation were statistically different among the three molecular subtypes.Analysis of immunotherapy response revealed that most immune checkpoint genes were differentially expressed in the three subtypes.A lower risk of immune escape was observed in Cluster1(C1),indicating higher sensitivity to immunotherapeutic drugs and subjects in this Cluster are more likely to benefit from immunotherapy.The pathways related to pancreatic cancer were differentially enriched among the three subtypes.Five genes,namely SFRP1,GIPR,EMP1,COL17A and CXCL11 were selected to construct a prognostic signature.Conclusions:Single-cell seq data were to classify pancreatic cancer into three molecular subtypes based on differences in clinical phenotype,mutation,immune characteristics and differentially enriched pathways.Five prognosis-related genes were identified for prediction of survival of pancreatic cancer patients and to evaluate the efficacy of immunotherapy in various subtypes. 展开更多
关键词 Pancreatic cancer Molecular subtypes Single-cell sequencing Immune microenvironment Tumor immunity
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Roles of gypsum/salt-bearing sequence in hydrocarbon accumulation and storage
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作者 Wenhui Liu Yining Li +5 位作者 Quanyou Liu xiaofeng wang Qingqiang Meng Dianwei Zhang Longfei Lu Houyong Luo 《Energy Geoscience》 2023年第1期93-102,共10页
Gypsum/salt beds are widely developed in petroliferous basins across the world.Most basins with gypsum/salt beds have been proven to host abundant hydrocarbon resources.Previous studies on the effects of gypsum/salt b... Gypsum/salt beds are widely developed in petroliferous basins across the world.Most basins with gypsum/salt beds have been proven to host abundant hydrocarbon resources.Previous studies on the effects of gypsum/salt beds on hydrocarbon reservoirs primarily focused on their excellent sealing property as cap rocks.However,an increasing number of exploration discoveries have shown that gypsum/salt beds have the potential to promote the formation of high-quality source rocks and hydrocarbon reservoirs.Gypsum/salt beds influence the generation,preservation and accumulation of hydrocarbons.Based on the systematic analysis of the generation of hydrocarbons in global gypsum/saltbearing sequences,the study discussed the control of gypsum/salt beds on play elements,and explore the relationship between the development of gypsum/salt beds and global large-and medium-scale hydrocarbon reservoirs.Furthermore,we analyzed the correlation between typical gypsum/saltbearing sequences and their hydrocarbon generation potentials in China.In-depth analysis shows three patterns in terms of the spatial superimposition of gypsum/salt beds and source rocks,that is,postsalt pattern,inter-salt pattern and pre-salt pattern.Among others,the source rocks of the inter-salt pattern are widely developed in salt basins and of great potential for hydrocarbon exploration. 展开更多
关键词 Gypsum/salt bed Hydrocarbon reservoir Source rock Play element
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The Global Boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System) 被引量:66
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作者 Xu Chen Jiayu Rong +7 位作者 Junxuan Fan Renbin Zhan Charles E. Mitchell David A. T. Harper Michael J. Melchin Ping'an Peng Stan C. Finney xiaofeng wang 《Episodes》 SCIE 2006年第3期183-196,共14页
The Global boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System) is defined at a point 0.39m below the base of the Kuanyinchiao Bed in the Wangj... The Global boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System) is defined at a point 0.39m below the base of the Kuanyinchiao Bed in the Wangjiawan North section. The section is located near Wangjiawan village, 42 km north of Yichang city (western Hubei, China), at 30° 58′56″N and 111° 25′10″E. The GSSP level coincides with the first appearance of the graptolite species Normalograptus extraordinarius (Sobolevskaya). Secondary markers include the onset of a positive carbon-isotope excursion, and a slightly earlier first appearance of Normalograptus ojsuensis ( Koren and Mikhailova ). The Wangjiawan North section possesses continuity of sedimentation and biozonation with completeness of exposures, abundant and well-preserved graptolites and shelly fossils, i. e. the Hirnantia- Dalmanitina shelly fauna which is a key element for recognition of the Hirnantian Stage. The Wangjiawan North, South and Riverside sections possess favorable facies and widespread correlation potential, are free from structure complication, metamorphism and other alteration, and have good accessibility. The Riverside section in particular possesses amenability to isotopic age determination. The beginning of the Hirnantian was followed by a global episode of a major extinction event, which happened in the Diceratograptus mirus Subzone. The proposal was voted by the International Subcommission on Ordovician Stratigraphy in October, 2004, approved by the International Commission on Stratigraphy in February, 2006, and ratified by the International Union of Geological Sciences in May, 2006. 展开更多
关键词 全球界线层型剖面和节点 奥陶纪 GSSP 地层学
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Antenatal taurine reduces cerebral cell apoptosis in fetal rats with intrauterine growth restriction 被引量:9
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作者 Jing Liu xiaofeng wang +3 位作者 Ying Liu Na Yang Jing Xu Xiaotun Ren 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第23期2190-2197,共8页
From pregnancy to parturition, Sprague-Dawley rats were daily administered a low protein diet to establish a model of intrauterine growth restriction. From the 12th day of pregnancy, 300 mg/kg taurine was daily added ... From pregnancy to parturition, Sprague-Dawley rats were daily administered a low protein diet to establish a model of intrauterine growth restriction. From the 12th day of pregnancy, 300 mg/kg taurine was daily added to food until spontaneous delivery occurred. Brain tissues from normal neonatal rats at 6 hours after delivery, neonatal rats with intrauterine growth restriction, and neo- natal rats with intrauterine growth restriction undergoing taurine supplement were obtained for fur- ther experiments. The terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick-end labeling assay revealed that the number of apoptotic cells in the brain tissue of neonatal rats with intrauterine growth restriction significantly increased. Taurine supplement in pregnant rats reduced cell apoptosis in brain tissue from neonatal rats with intrauterine growth restriction. Immu- nohistochemical staining revealed that taurine supplement increased glial cell line-derived neuro- trophic factor expression and decreased caspase-3 expression in the cerebral cortex of intrauterine growth-restricted fetal rats. These results indicate that taurine supplement reduces cell apoptosis through the glial cell line-derived neurotrophic factor-caspase-3 signaling pathway, resulting in a protective effect on the intrauterine growth-restricted fetal rat brain. 展开更多
关键词 neural regeneration intrauterine growth restriction fetal rats brain neural cells TAURINE cell apop-tosis glial cell line-derived neurotrophic factor caspase-3 neural development grants-supportedpaper NEUROREGENERATION
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Effect of terrain on landscape patterns and ecological effects by a gradient-based RS and GIS analysis 被引量:6
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作者 Wenfeng Gong Haibo wang +2 位作者 xiaofeng wang Wenyi Fan Philip Stott 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第5期1061-1072,共12页
Terrain is an important environment factor that plays a vital role in human development by influencing the spatial layout of land use patterns. The terrain niche index, combined with slope and elevation, can comprehen... Terrain is an important environment factor that plays a vital role in human development by influencing the spatial layout of land use patterns. The terrain niche index, combined with slope and elevation, can comprehensively present detailed information about spatial differences in terrain and is superior to single terrain factors. We applied remote sensing and geographical information system to terrain gradient, used the non-dimensional distribution index to examine spatial distribution characteristics of various landscape types, and analyzed the ecological effects of landscape were quantitatively on terrain gradients. Eco-environment quality (EEQ) was evaluated using the forestry operation area as the evaluation unit. The spatial distributions in various landscapes were significantly influenced by terrain factors, especially by bodies of water, cropland and residential land. The spatial distribution varied greatly in different terrain gradients for similar landscape types. The areas associated with good, intermediate and poor EEQ were occupied primarily by natural landscape, semi-natural and largely artificial landscapes, respectively. 展开更多
关键词 Terrain niche index Spatial distribution characteristics Distribution index Eco-environment quality
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Efficacy and safety of degarelix in patients with prostate cancer:Results from a phase III study in China 被引量:3
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作者 Yinghao Sun Liping Xie +4 位作者 Tao Xu Jorn S.Jakobsen Weiqing Han Per S.Sorensen xiaofeng wang 《Asian Journal of Urology》 CSCD 2020年第3期301-308,共8页
Objective:To establish non-inferiority of gonadotropin-releasing hormone degarelix compared with goserelin in suppressing and maintaining castrate testosterone levels from Day 28 to Day 364 in Chinese patients with pr... Objective:To establish non-inferiority of gonadotropin-releasing hormone degarelix compared with goserelin in suppressing and maintaining castrate testosterone levels from Day 28 to Day 364 in Chinese patients with prostate cancer.Methods:This is an open-label,multi-centre study in which men aged18 years were randomised in a 1:1 ratio to once-a-month subcutaneous injection of either degarelix(240/80 mg)or goserelin(3.6 mg)for 12 months.The primary endpoint was difference in 1-year cumulative probability of suppressing testosterone to ≤0.5 ng/mL.Non-inferiority was to be established if the lower 95% confidence interval(CI)limit for difference in cumulative probability between the treatment arms was greater than -10%.Secondary endpoints included cumulative probability of prostate-specific-antigen-progression-free-survival(PSA-PFS).Safety was also assessed.Results:Baseline demographics and disease characteristics were similar between degarelix(n=142)and goserelin(n=141)treatment arms.The difference in cumulative probability of maintaining castrate levels from Day 28-364 was 3.6%(95%CI:-1.5%,8.7%),demonstrating non-inferiority of degarelix.The cumulative probability of PSA-PFS at Day 364 was higher for degarelix(82.3%,95%CI:74.7%,87.7%)versus goserelin(71.7%,95%CI:63.2%,78.5%,p=0.038).Adverse events(AEs)were similar between treatment arms,except for more injection site reactions with degarelix versus goserelin.Four(2.8%)and nine(6.4%)patients discontinued due to AEs in degarelix and goserelin groups,respectively. 展开更多
关键词 DEGARELIX GOSERELIN GnRH antagonist GnRH agonist Prostate cancer China
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Analysis of the Relationship between the Cloud Water Path and Precipitation Intensity of Mature Typhoons in the Northwest Pacific Ocean 被引量:2
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作者 Shuang LUO Yunfei FU +2 位作者 Shengnan ZHOU xiaofeng wang Dongyong wang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第4期359-376,共18页
The relationship between precipitation intensity and cloud water in typhoon systems remains unclear.This study combined time-and space-synchronized precipitation and spectral data obtained by the Precipitation Radar(P... The relationship between precipitation intensity and cloud water in typhoon systems remains unclear.This study combined time-and space-synchronized precipitation and spectral data obtained by the Precipitation Radar(PR)as well as the Visible and Infrared Scanner(VIRS)onboard the TRMM satellite,to overcome the limitations of precipitation properties and cloud parameters not being synchronized in previous studies.A merged dataset of near-surface rain rate(RR)and corresponding cloud water path(CWP)was established and used to analyze the potential correlation between cloud microphysical properties and precipitation,to deepen our understanding of the evolution of cloud to rain.In addition,25 collocated satellite overpasses of mature typhoon cases in the Northwest Pacific Ocean from 1998 to 2012 were obtained,and the relationships between the CWP and RR of 144515 pixels were analyzed in detail.The results show that the CWP and RR of mature typhoon systems with different precipitation types,precipitation cloud phases,and vertical depths of precipitation can be fitted by a notable sigmoid function,which may be useful for estimating CWP and parameterizing precipitation in models.Furthermore,the relationship was applied and tested with an independent sample to show that RR is a significant indicator of CWP. 展开更多
关键词 cloud water PATH convective PRECIPITATION STRATIFORM PRECIPITATION TRMM tropical cyclone
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High-Performance Photo-Modulated Thin-Film Transistor Based on Quantum dots/Reduced Graphene Oxide Fragment-Decorated ZnO Nanowires 被引量:2
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作者 Zhi Tao Yi-an Huang +7 位作者 Xiang Liu Jing Chen Wei Lei xiaofeng wang Lingfeng Pan Jiangyong Pan Qianqian Huang Zichen Zhang 《Nano-Micro Letters》 SCIE EI CAS 2016年第3期247-253,共7页
In this paper, a photo-modulated transistor based on the thin-film transistor structure was fabricated on the flexible substrate by spin-coating and magnetron sputtering. A novel hybrid material that composed of Cd Se... In this paper, a photo-modulated transistor based on the thin-film transistor structure was fabricated on the flexible substrate by spin-coating and magnetron sputtering. A novel hybrid material that composed of Cd Se quantum dots and reduced graphene oxide(RGO) fragment-decorated ZnO nanowires was synthesized to overcome the narrow optical sensitive waveband and enhance the photo-responsivity. Due to the enrichment of the interface and heterostructure by RGO fragments being utilized, the photo-responsivity of the transistor was improved to 2000 AW^(-1) and the photo-sensitive wavelength was extended from ultraviolet to visible. In addition, a positive back-gate voltage was employed to reduce the Schottky barrier width of RGO fragments and ZnO nanowires. As a result, the amount of carriers was increased by 10 folds via the modulation of back-gate voltage. With these inherent properties, such as integrated circuit capability and wide optical sensitive waveband, the transistor will manifest great potential in the future applications in photodetectors. 展开更多
关键词 Thin-film TRANSISTOR Quantum DOTS Reduced graphene oxide ZnO NANOWIRES
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Pseudo-capacitance of ruthenium oxide/carbon black composites for electrochemical capacitors 被引量:3
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作者 xiaofeng wang Dianbo Ruan +1 位作者 Peng wang Yiqiang Lu 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期816-821,共6页
Hydrous ruthenium oxide was formed by a new process. The precursor was obtained by mixing the aqueous solutions of RuCl3xH2O and NaHCO3. The addition of NaHCO3 led to the formation of an oxide with extremely fine RuO2... Hydrous ruthenium oxide was formed by a new process. The precursor was obtained by mixing the aqueous solutions of RuCl3xH2O and NaHCO3. The addition of NaHCO3 led to the formation of an oxide with extremely fine RuO2 particles forming a porous network structure in the oxide electrode. Polyethylene glycol was added as a controller to partly inhibit the sol-gel reaction. The rate capacitance of 530 F·g^-1 was measured for the powder formed at an optimal annealing temperature of 210℃. Several details concerning this new material, including crystal structure, particle size as a function of temperature, and electrochemical properties, were also reported. In addition, the rate capacitance of the composite electrode reached 800 F·g^-1 after carbon black was added. By using the modified electrode of a RuO2/carbon black composite electrode, the electrochemical capacitor exhibits high energy density and stable power characteristics. The values of specific energy and maximum specific power of 24 Wh·kg^-1 and 4 kW·kg^-1, respectively, are demonstrated for a cell voltage between 0 and 1 V. 展开更多
关键词 electrochemical capacitor ruthenium oxide polyethylene glycol carbon black
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TOEPLITZ OPERATORS WITH POSITIVE OPERATOR-VALUED SYMBOLS ON VECTOR-VALUED GENERALIZED FOCK SPACES 被引量:2
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作者 Jianjun CHEN xiaofeng wang Jin XIA 《Acta Mathematica Scientia》 SCIE CSCD 2020年第3期625-640,共16页
In this article,we study some characterizations of Toeplitz operators with positive operator-valued function as symbols on the vector-valued generalized Bargmann-Fock spaces Fψ^2.Main results including Fock-Carleson ... In this article,we study some characterizations of Toeplitz operators with positive operator-valued function as symbols on the vector-valued generalized Bargmann-Fock spaces Fψ^2.Main results including Fock-Carleson condition,bounded Toeplitz operators,compact Toeplitz operators,and Toeplitz operators in the Schatten-p class are all considered. 展开更多
关键词 Toeplitz operator operator-valued symbol generalized Fock space
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Spatiotemporal variation and driving factors of water yield services on the Qingzang Plateau 被引量:4
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作者 xiaofeng wang Bingyang Chu +4 位作者 Xiaoming Feng Yuehao Li Bojie Fu Shirong Liu Jiming Jin 《Geography and Sustainability》 2021年第1期31-39,共9页
Water resources are a basic need for social sustainable development and human existence.As an important national strategy for water resources security,spatial and temporal patterns and driving mechanisms of water yiel... Water resources are a basic need for social sustainable development and human existence.As an important national strategy for water resources security,spatial and temporal patterns and driving mechanisms of water yield ecosystem services on the Qingzang Plateau(QP)are critical for water resources management,optimal water allocation and the improvement of ecological water protection efficiency.However,only a few relevant studies are currently available.In this study,we simulated the water yield(WY)of the QP over 34 years,from 1982 to 2015,using the InVEST model and analyzed the spatiotemporal dynamic relationships between WY and climate change as well as between WY and vegetation change,using geographically weighted regression(GWR)models.The results showed that:1)from 1982 to 2015,the WY of the QP increased at an average rate of 3.8 mm/yr;2)WY presented a reduced spatial pattern from southeast to northwest;and 3)the WY driving factors have individual and spatial differences.In terms of the area percentage in promoting WY when analyzing each driving factor,precipitation(99.8%)and air pressure(53.3%)played the major roles in promoting WY,while temperature(71.9%),wind speed(57.2%),net primary productivity(87.2%),radiation(68.3%)and lake(87.7%)played negative roles.The areas where WY are dominated by temperature are the largest(41.1%),and followed by areas dominated by pressure(19.7%)and precipitation(18.5%).The results of this study provide scientific support for formulating regional water resources policy,social and economic development planning and other macro decisions for the QP. 展开更多
关键词 Qingzang Plateau Water yield GWR models
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Photosynthetic biomaterials: applications of photosynthesis in algae as oxygenerator in biomedical therapies 被引量:1
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作者 Yong wang Yanan Xue +8 位作者 Tao Zhang Qingqing Fang Mingyuan Jin xiaofeng wang Zhengcai wang Yanyan Hu Wanyi Zhao Dong Lou Wei-Qiang Tan 《Bio-Design and Manufacturing》 SCIE EI CSCD 2021年第3期596-611,共16页
For most organisms,molecular oxygen is indispensable for normal physiological metabolism;in humans,prolonged hypoxia in tissues can induce many diseases,exemplified by cardiovascular disease,chronic wounds,and tissue ... For most organisms,molecular oxygen is indispensable for normal physiological metabolism;in humans,prolonged hypoxia in tissues can induce many diseases,exemplified by cardiovascular disease,chronic wounds,and tissue necrosis.Therefore,the oxygen in our environment is vital for life.As a main source of oxygen in the natural world that transforms light energy into chemical energy and oxygen,photosynthesis has been widely studied in scientific research and used in production of food,fuel,and medicine.In recent years,photosynthesis has become more closely involved in biomedicine and has been widely used in photodynamic therapy,tissue regeneration,transplantation,and in treatment of specific diseases.This review summarizes innovative applications of photosynthesis in biomedical research and highlights the theory and implications of clinical treatment for specific diseases. 展开更多
关键词 BIOMATERIALS PHOTOSYNTHESIS Hypoxia Myocardial infarction Photodynamic therapy Tissue engineering
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Cytotoxic T-lymphocytes response in vitro activated by dendritic cells pulsed with heat shock protein 70 derived from human bladder tumor cell lines of EJ 被引量:1
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作者 Lingfeng He Jianhua wang +5 位作者 xiaofeng wang Xiangjun He Zheng Yan Kexin Xu Kaopeng Guan Shukun Hou 《The Chinese-German Journal of Clinical Oncology》 CAS 2008年第12期713-718,共6页
Objective: To investigate whether human dendritic cells (DC) derived from peripheral blood mononuclear cells (PBMC), which were pulsed by heat shock protein 70 (HSP70) isolated from human bladder tumor cell lin... Objective: To investigate whether human dendritic cells (DC) derived from peripheral blood mononuclear cells (PBMC), which were pulsed by heat shock protein 70 (HSP70) isolated from human bladder tumor cell lines of E J, were able to induce peptide specific cytotoxic T-lymphocytes (CTL) response in vitro and give the experimental foundation for the future clinical trials of immunotherapy in bladder tumor. Methods: The E J-derived HSP70 co-cultured with DC from the healthy volunteers' PBMC, along with the crude lysate (the supematant before HSP70 purification) from EJ cells were used as the experimental groups and DC not pulsed by any tumor cells antigen were the blank control. The autologous T-lymphocytes were added into the above various DC groups, and after incubation, the stimulation indexes (SI) and interferon-y (IFN-γ) were detected to evaluate the immune activities of various DC groups. The killing effects of CTL to target cells, EJ and Hela cells, were determined with 51^Cr releasing test. Results: Both DC/HSP70 and DC/the crude lysate could effectively activate CTL in vitro and kill target cells EJ. The killing effect of DC/HSP70 to EJ was much stronger than DC/the crude lysate (the supernatant before HSP70 purification) (P 〈 0.05). DC without any tumor cell antigens had a lower killing power to EJ. Meanwhile, DC/ HSP70 had little killing power to Hela non-relevant to bladder tumor histopathologically as compared with EJ cells (P 〈 0.05). Conclusion: The DC pulsed by HSP70 derived from the autologous tumor cells could induce a peptide complexes specific CTL response to tumor cells, and the CTL response induced by the DC/HSP70 was stronger, which display the basis of the possible clinical application of DC/HSP70 for bladder tumor. 展开更多
关键词 heat shock protein 70 (HSP70) dendritic cells (DC) cytotoxic T-lymphocytes (CTL) bladder tumor
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Concentration-induced structural diversity and catalytic activity of BF3/n-BuOH complexes for n-decene polymerization
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作者 Jun wang Hongpeng Li +7 位作者 Xi Chen Weiguang Shi Na Zhang Fuquan Bai xiaofeng wang Sihan wang Xianming Xu Libo wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2687-2695,共9页
The BF3/n-BuOH complexes were investigated as active species in catalyzing n-decene polymerization reaction.The structures of BF3/n-BuOH complexes were characterized not only by modern spectrum but also by calculation... The BF3/n-BuOH complexes were investigated as active species in catalyzing n-decene polymerization reaction.The structures of BF3/n-BuOH complexes were characterized not only by modern spectrum but also by calculation at theoretical level. The results confirmed that BF3/n-BuOH complexes changed from BF3·(n-BuOH)2 complexes to BF3·n-BuOH complexes with the mass fraction of BF3 increasing. These two complexes have different catalytic activity, but BF3·n-BuOH was superior. The highest n-decene conversion could reach 99% and the most excellent selectivity of n-decene trimer and tetramer could reach up to 80% yield by a series of controlled conditions. This work can help to understand the catalytic active species of n-decene polymerization and provide support for industrialization of poly-alpha-olefins(PAOs). 展开更多
关键词 BORON TRIFLUORIDE n-BuOH n-decene POLYMERIZATION Catalyst structures
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北京市种猪集中测定情况分析与展望 被引量:1
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作者 李爽 郭峰 +2 位作者 王晓凤 郑美丽 陈少康 《猪业科学》 2021年第10期112-114,共3页
为掌握北京市种猪生产性能水平,文章对2015—2020年北京市种猪集中收测结果,包括达100 kg体重日龄、达100 kg体重活体背膘厚、30~100 kg平均日增重和饲料转化率相关数据进行了分析比较,并结合种猪生产企业现状,对集中测定的重要性进行... 为掌握北京市种猪生产性能水平,文章对2015—2020年北京市种猪集中收测结果,包括达100 kg体重日龄、达100 kg体重活体背膘厚、30~100 kg平均日增重和饲料转化率相关数据进行了分析比较,并结合种猪生产企业现状,对集中测定的重要性进行探讨与展望,以期为指导种猪选育,开展联合育种工作提供更多思路。 展开更多
关键词 种猪 生产性能 集中测定
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