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Fighting hypoxia to improve photodynamic therapy-driven immunotherapy:Alleviating,exploiting and disregarding
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作者 Liangliang Jia Ye Hong +7 位作者 Xinyu He Ying Zhou Liujiao Ren Hongjun Du bin Zhao bin qin Zhe Yang Di Gao 《Chinese Chemical Letters》 2025年第2期29-40,共12页
Innovative anti-cancer therapies that activate the immune system show promise in combating cancers resistant to conventional treatments.Photodynamic therapy(PDT)is one such treatment,which not only directly eliminates... Innovative anti-cancer therapies that activate the immune system show promise in combating cancers resistant to conventional treatments.Photodynamic therapy(PDT)is one such treatment,which not only directly eliminates tumor cells but also functions as an in situ tumor vaccine by enhancing tumor immunogenicity and triggering anti-tumor immune responses through immunogenic cell death(ICD).However,the effectiveness of PDT in enhancing immune responses is influenced by factors,such as photosensitizers and the tumor microenvironment,particularly hypoxia.Current clinically used PDT heavily relies on oxygen(O_(2))availability and can be limited by tumor hypoxia.Additionally,the tumor immunosuppressive microenvironment induced by hypoxia affects the anti-tumor immunity of tumor-infiltrating effector T cells.Meanwhile,the immunosuppressive myeloid-lineage cells are recruited to the hypoxic tumor tissue and exhibit higher immunosuppressive capabilities under hypoxia conditions.Consequently,numerous strategies have been developed to modulate tumor hypoxia or to create hypoxia-compatible PDT,aiming to reduce the effects of tumor hypoxia on PDT-driven immunotherapy.This review investigates these strategies,including approaches to alleviate,exploit,and disregard tumor hypoxia within the context of PDT/immunotherapy.It also emphasizes the role of advanced nanomedicine and its benefits in these strategies,while outlining current challenges and future prospects in the field. 展开更多
关键词 Photodynamic therapy Tumor hypoxia IMMUNOTHERAPY Immunogenic cell death PHOTOSENSITIZERS NANOMEDICINE
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Clinical features of early esophageal neoplastic lesions at different stages and efficacy and prognosis after endoscopic submucosal dissection
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作者 Yuan-Miao Zhang Ning Zhu +9 位作者 Meng-Yao Chen Fang-Lan Li bin qin Jiong Jiang Shen-Hao Wang Jie Wu Xiao-Jing Quan Chu-Ying Wang Ying Zheng Bai-Cang Zou 《World Journal of Gastroenterology》 2025年第38期80-94,共15页
BACKGROUND Esophageal cancer is a common malignancy,and endoscopic submucosal dissection(ESD)is the treatment of choice for early esophageal cancer.AIM To analyze clinicopathological features,ESD efficacy,and prognost... BACKGROUND Esophageal cancer is a common malignancy,and endoscopic submucosal dissection(ESD)is the treatment of choice for early esophageal cancer.AIM To analyze clinicopathological features,ESD efficacy,and prognostic factors of differentiated esophageal neoplasms to optimize management strategies.METHODS A total of 264 Lesions in 245 patients treated with ESD(2014-2022)were retrospectively analyzed.Lesions were categorized as low-grade intraepithelial neoplasia(LGIN),high-grade intraepithelial neoplasia,early-stage carcinoma,or superficial carcinoma.Clinicopathological data and outcomes were compared.RESULTS Early-stage cancers showed more surface vesicles than LGIN(P=0.002).Intraepithelial papillary capillary loop(IPCL)-A predominated in LGIN,while IPCL-B2 was frequent in cancer(P<0.001).Superficial carcinomas had higher vertical margin positivity(P<0.001).Curative resection correlated with differentiation,body mass index(BMI),and symptoms;complications were linked to gender,BMI,and lesion size.The 3-,5-,and 8-year disease-free survival rates were 96.8%,91.7%,and 86.4%,respectively.Age[hazard ratio(HR)=1.018]and prior esophageal cancer(HR=3.050)predicted poorer survival.CONCLUSION Differentiated esophageal neoplasms exhibit distinct clinicopathological features.ESD provides durable efficacy,but high-risk patients(older age,prior cancer)require vigilant surveillance. 展开更多
关键词 Esophageal intraepithelial neoplasia Early esophageal cancer Superficial esophageal cancer Endoscopic submucosal dissection Long-term outcomes
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Research progress and perspectives on rechargeable batteries
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作者 Gaojing Yang Zhimeng Hao +79 位作者 Chun Fang Wen Zhang Xia-hui Zhang Yuyu Li Zhenhua Yan Zhiyuan Wang Tao Sun Xiaofei Yang Fei Wang Chengzhi Zhang Hongchang Jin Shuaifeng Lou Nan Chen Yiju Li Jia-Yan Liang Le Yang Shouyi Yuan Jin Niu Shuai Li Xu Xu Dong Wang Song Jin Bo-Quan Li Meng Zhao Changtai Zhao Baoyu Sun Xiaohong Wu Yuruo Qi Lili Wang Nan Li bin qin Dong Yan Xin Cao Ting Jin Peng Wei Jing Zhang Jiaojiao Liang Li Liu Ruimin Sun Zengxi Wei Xinxin Cao Kaixiang Lei Xiaoli Dong Xijun Xu Xiaohui Rong Zhaomeng Liu Hongbo Ding Xuanpeng Wang Zhanheng Yan Guohui qin Guanghai Chen Yaxin Chen Ping Nie Zhi Chang Fang Wan Minglei Mao Zejing Lin Anxing Zhou Qiubo Guo Wen Luo Xiaodong Shi Yan Guo Longtao Ma Xiangkun Ma Jiangjiang Duan Zhizhang Yuan Jiafeng Lei Hao Fan Jinlin Yang Chao Li Tong Zhou Jiabiao Lian Jin Zhao Huanxin Ju Tinglu Song Zulipiya Shadike Weiguang Lv Jiawei Wen Lingxing Zeng Jianmin Ma 《Chinese Chemical Letters》 2025年第10期9-93,共85页
Energy storage plays a critical role in sustainable development,with secondary batteries serving as vital technologies for efficient energy conversion and utilization.This review provides a comprehensive summary of re... Energy storage plays a critical role in sustainable development,with secondary batteries serving as vital technologies for efficient energy conversion and utilization.This review provides a comprehensive summary of recent advancements across various battery systems,including lithium-ion,sodium-ion,potassium-ion,and multivalent metal-ion batteries such as magnesium,zinc,calcium,and aluminum.Emerging technologies,including dual-ion,redox flow,and anion batteries,are also discussed.Particular attention is given to alkali metal rechargeable systems,such as lithium-sulfur,lithium-air,sodium-sulfur,sodium-selenium,potassium-sulfur,potassium-selenium,potassium-air,and zinc-air batteries,which have shown significant promise for high-energy applications.The optimization of key components—cathodes,anodes,electrolytes,and interfaces—is extensively analyzed,supported by advanced characterization techniques like time-of-flight secondary ion mass spectrometry(TOF-SIMS),synchrotron radiation,nuclear magnetic resonance(NMR),and in-situ spectroscopy.Moreover,sustainable strategies for recycling spent batteries,including pyrometallurgy,hydrometallurgy,and direct recycling,are critically evaluated to mitigate environmental impacts and resource scarcity.This review not only highlights the latest technological breakthroughs but also identifies key challenges in reaction mechanisms,material design,system integration,and waste battery recycling,and presents a roadmap for advancing high-performance and sustainable battery technologies. 展开更多
关键词 Rechargeable batteries Electrode materials Electrolyte chemistry Characterization technologies Battery recycling
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Analyzing the Dynamic Characteristics of Angular Contact Ball Bearings Considering Three-Dimensional Localized Raceway Defects
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作者 Zhen Li qingshan Wang +2 位作者 Ruihua Wang bin qin Wen Shao 《Chinese Journal of Mechanical Engineering》 2025年第6期616-643,共28页
Current research on localized raceway defects of angular contact ball bearings(ACBB)mainly focuses on assuming that localized raceway defects are cube-shaped defects characterized using a half-sine displacement excita... Current research on localized raceway defects of angular contact ball bearings(ACBB)mainly focuses on assuming that localized raceway defects are cube-shaped defects characterized using a half-sine displacement excitation function.However,the assumption of a cube-shaped defect cannot accurately reflect the morphological characteristics of a localized raceway defect,and the half-sine displacement excitation function cannot be used to accurately describe the relationship between the geometric positions of rolling element and raceway in the region of localized raceway defects.In this study,a comprehensive dynamic model of an ACBB considering a three-dimensional localized raceway defect is established based on the nonlinear Hertz contact theory in conjunction with the outer raceway control theory using the improved Newton–Raphson iteration method.Three localized raceway defect distribution types,namely symmetric,offset,and deflection distributions,are considered.The established model is verified by comparing the results of the proposed model with those of existing literature.The dynamic characteristics of the ACBB were analyzed by investigating the effects of the geometrical size and distribution types on the time-varying contact angles,contact forces,and diagonal stiffness of the ACBB.The investigation results show that the appearance of localized raceway defect leads to the time-varying curves of contact angles,contact forces and diagonal stiffness havingΛ-and V-shaped mutations in some time intervals;The variation tendencies of theΛ-and V-shaped mutations are significant with the increase in defect radial depth H,defect axial width a and angular distanceθ_b.The increase in defect eccentric distance L is beneficial to the rolling elements disengaging from the defect area and it can weaken the influence of localized raceway defect on the time-varying contact and stiffness characteristics of ACBB.The time-varying contact and stiffness characteristics appear to change significantly when the defect deflection angleα_βincrease toα_γ.The results of this study provide a theoretical basis for the fault diagnosis of localized raceway defects in ACBB. 展开更多
关键词 Defect radial depth Defect axial width Deflection angle Contact angle Diagonal stiffness
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Clinical characteristics and risk factors of esophageal reflux hypersensitivity:A multicenter study
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作者 Yan-Ping Wu Jia-Xuan Zhou +6 位作者 Hong-Bo Wu Di-Ping Wu Ling-Zhi qin bin qin Xiao-Yu Xu Saleh Abdulaziz Abdulgani Yehya Yan Cheng 《World Journal of Gastroenterology》 2025年第17期20-28,共9页
BACKGROUND Reflux hypersensitivity(RH)constitutes roughly 14%of patients with heartburn and 34%of those with refractory heartburn,yet it is inadequately comprehended.AIM To investigate the clinical characteristics and... BACKGROUND Reflux hypersensitivity(RH)constitutes roughly 14%of patients with heartburn and 34%of those with refractory heartburn,yet it is inadequately comprehended.AIM To investigate the clinical characteristics and risk factors associated with RH.METHODS We conducted a retrospective analysis of 109 patients with RH and 384 healthy controls from three medical centers between January 2022 and December 2023.Comprehensive data encompassing symptoms,motility,impedance-pH monitoring,and psychological evaluations were collected.RESULTS RH patients encountered a greater frequency of weakly acidic reflux(WAR)events compared to acidic reflux or nonacidic reflux(NAR)events.Upright reflux time(1.22%)exceeds supine reflux time(0.54%)(P<0.05).Extraesophageal symptoms were more prevalent among younger patients and those with elevated NAR(P<0.05).The acidic reflux,WAR,NAR,and peristaltic contraction break length in male patients exceeded those in female patients(P<0.05).Age[odds ratio(OR)=5.633],hiatal hernia(OR=13.103),and anxiety(OR=17.342)constituted independent risk factors for RH.CONCLUSION WAR and NAR are pivotal in RH.Patients with increased NAR are more likely to experience extraesophageal symptoms.Age,hiatal hernia,and anxiety are significant independent risk factors for RH. 展开更多
关键词 Gastroesophageal reflux disease Functional esophageal disease Reflux hypersensitivity Clinical characteristics Risk factors
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Developing and validating a computed tomography radiomics strategy to predict lymph node metastasis in pancreatic cancer
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作者 Shuai Ren bin qin +3 位作者 Marcus J Daniels Liang Zeng Ying Tian Zhong-Qiu Wang 《World Journal of Radiology》 2025年第8期44-54,共11页
BACKGROUND Lymph node metastasis(LNM)is a key prognostic factor in pancreatic cancer(PC).Accurate preoperative prediction of LNM remains challenging.Radiomics offers a noninvasive method to extract quantitative imagin... BACKGROUND Lymph node metastasis(LNM)is a key prognostic factor in pancreatic cancer(PC).Accurate preoperative prediction of LNM remains challenging.Radiomics offers a noninvasive method to extract quantitative imaging features that may aid in predicting LNM.AIM To investigate the potential value of a computed tomography(CT)-based radiomics model in prediction of LNM in PC.METHODS A retrospective analysis was performed on 168 pathologically confirmed PC patients who underwent contrast-enhanced-CT.Among them,107 cases had no LNM,while 61 cases had confirmed LNM.These patients were randomly divided into a training cohort(n=135)and a validation cohort(n=33).A total of 792 radiomics features were extracted,comprising 396 features from the arterial phase and another 396 from the portal venous phase.The Minimum Redundancy Maximum Relevance and Least Absolute Shrinkage and Selection Operator methods were used for feature selection and Radiomics model construction.The receiver operating characteristic curve was employed to assess the diagnostic potential of the model,and DeLong test was used to compare the area under the curve(AUC)values of the model.RESULTS Six radiomics features from the arterial phase and nine from the portal venous phase were selected.The Radscore model demonstrated strong predictive performance for LNM in both the training and test cohorts,with AUC values ranging from 0.86 to 0.94,sensitivity between 66.7% and 91.7%,specificity from 71.4% to 100.0%,accuracy between 78.8%and 91.1%,PPV ranging from 64.7% to 100.0%,and negative predictive value between 84.0% and 93.8%.No significant differences in AUC values were observed between the arterial and portal venous phases in either the training or test set.CONCLUSION The preoperative CT-based radiomics model exhibited robust predictive capability for identifying LNM in PC. 展开更多
关键词 Computed tomography Radiomics Lymph node metastasis Pancreatic cancer Model construction
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基于案例推理的高校“双创”实现路径优选 被引量:1
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作者 宾芹 向琳 《创新与创业教育》 2020年第1期81-85,共5页
"双创"是现代化经济体系建设的战略支撑之一,高校是创新创业发展的重要基地。但目前高校的"双创"建设没有全面系统的方案作为参考,其发展参差不齐。通过调查高校"双创"建设的成功案例,进行比较分析,发现... "双创"是现代化经济体系建设的战略支撑之一,高校是创新创业发展的重要基地。但目前高校的"双创"建设没有全面系统的方案作为参考,其发展参差不齐。通过调查高校"双创"建设的成功案例,进行比较分析,发现创新创业平台、创新创业教育、创新团队、导师制、校企合作五个方面对高校"双创"影响较为显著,并针对性地提出了对策建议,以期为高校"双创"和创新型国家建设提供有益借鉴。 展开更多
关键词 “双创” 导师制 校企合作
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Wind Speed Prediction Based on Improved VMD-BP-CNN-LSTM Model
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作者 Chaoming Shu bin qin Xin Wang 《Journal of Power and Energy Engineering》 2024年第1期29-43,共15页
Amid the randomness and volatility of wind speed, an improved VMD-BP-CNN-LSTM model for short-term wind speed prediction was proposed to assist in power system planning and operation in this paper. Firstly, the wind s... Amid the randomness and volatility of wind speed, an improved VMD-BP-CNN-LSTM model for short-term wind speed prediction was proposed to assist in power system planning and operation in this paper. Firstly, the wind speed time series data was processed using Variational Mode Decomposition (VMD) to obtain multiple frequency components. Then, each individual frequency component was channeled into a combined prediction framework consisting of BP neural network (BPNN), Convolutional Neural Network (CNN) and Long Short-Term Memory Network (LSTM) after the execution of differential and normalization operations. Thereafter, the predictive outputs for each component underwent integration through a fully-connected neural architecture for data fusion processing, resulting in the final prediction. The VMD decomposition technique was introduced in a generalized CNN-LSTM prediction model;a BPNN model was utilized to predict high-frequency components obtained from VMD, and incorporated a fully connected neural network for data fusion of individual component predictions. Experimental results demonstrated that the proposed improved VMD-BP-CNN-LSTM model outperformed other combined prediction models in terms of prediction accuracy, providing a solid foundation for optimizing the safe operation of wind farms. 展开更多
关键词 Wind Speed Forecast Long Short-Term Memory Network BP Neural Network Variational Mode Decomposition Data Fusion
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内镜热损伤术后息肉样结节瘢痕的病理性质及处理策略探讨 被引量:1
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作者 杨津 秦斌 +8 位作者 朱洪怡 伍洁 秦赟 姜炅 程妍 张莉 全晓静 龚均 邹百仓 《中国内镜杂志》 2022年第4期81-85,共5页
目的 总结内镜热损伤治疗术后息肉样结节瘢痕(PNS)的病理性质和发生机制,并探讨处理策略。方法 选择2015年3月-2019年3月于该科行内镜氩等离子体凝固术(APC)、内镜下黏膜切除术(EMR)和内镜黏膜下剥离术(ESD)治疗胃黏膜增生性病变的患者... 目的 总结内镜热损伤治疗术后息肉样结节瘢痕(PNS)的病理性质和发生机制,并探讨处理策略。方法 选择2015年3月-2019年3月于该科行内镜氩等离子体凝固术(APC)、内镜下黏膜切除术(EMR)和内镜黏膜下剥离术(ESD)治疗胃黏膜增生性病变的患者,回顾性分析发生PNS的7例患者的诊治及随访资料。同时,在中国知网(CNKI)、万方数据知识服务平台、中国生物医学数据库等中国数据库以及PubMed、Science Direct Online (SDOL)等国外数据库中检索相关文献,总结PNS的病理特征及随访结果。结果 临床资料:该科内镜治疗黏膜增生性病变后PNS发生率为1.21%(7/579),男5例,女2例,病变均位于胃窦。4例追加了ESD,术后标本切缘病理阴性,但随访复查中,手术瘢痕处再次发现息肉样结节。另外3例PNS未追加治疗,其中1例术后3个月发现息肉样结节,未作处理,术后6个月复查结节消失。文献检索结果:中文数据库无相关文献,在Science Direct Online (SDOL)和PubMed中检索到2篇相关文献,1篇为ESD术后发生PNS的个案报道,另一篇为多中心研究,前一篇文献资料包含在后一篇文献中。多中心研究文献显示:ESD术后PNS总体发病率为1.23%,各中心PNS发病率为0.15%~11.40%,所有发生PNS的患者原发病变均位于胃远端,长期随访无恶性肿瘤复发,17.86%的病例PNS于平均随访18个月后消失。结论 只要原发病变根治性切除,PNS在组织学上仅显示为再生和增生性组织,应被视为良性病变,除定期复查外,不需任何干预,即使内镜下切除,仍有可能复发。 展开更多
关键词 息肉样结节瘢痕 热损伤治疗术 病理 发生机制 处理策略
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鳜KLF6序列特征、组织表达及其对BCAAs代谢酶基因表达的影响
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作者 宾琴 宾石玉 +5 位作者 包凌晟 褚武英 张建社 程聪益 曾维 姚舟 《广西师范大学学报(自然科学版)》 CAS 北大核心 2024年第6期236-243,共8页
为研究鳜KLF6基因序列特征、组织表达及其对支链氨基酸代谢酶基因表达的影响,通过在线工具和软件对KLF6基因进行生物信息学分析,运用实时荧光定量PCR(RT-qPCR)技术,检测KLF6基因在鳜7个不同组织的表达丰度及用siRNA干扰后KLF6基因和BCAA... 为研究鳜KLF6基因序列特征、组织表达及其对支链氨基酸代谢酶基因表达的影响,通过在线工具和软件对KLF6基因进行生物信息学分析,运用实时荧光定量PCR(RT-qPCR)技术,检测KLF6基因在鳜7个不同组织的表达丰度及用siRNA干扰后KLF6基因和BCAAs代谢相关酶基因的mRNA表达量。结果表明:鳜KLF6基因编码区全长为3791 bp(登录号:XM_044176560.1),其中5′端和3′端分别为271和2659 bp,开放阅读框860 bp,共编码氨基酸286个。与鳃棘鲈KLF6基因的亲缘关系最近(98.6%),与鲤鱼较远(82.3%)。KLF6有1个KLF6-N型结构域(2-204 aa)、1个COG5048结构域(194-268 aa)和3个Znf-C2H2结构域(分别位于203-227、233-257、263-285个氨基酸之间)。鳜KLF6蛋白二级结构由无规则卷曲(56.99%)、α-螺旋(26.22%)、延伸链(10.84%)和β-转角(5.94%)相互连接而成。RT-qPCR结果发现,KLF6基因在鳜组织的相对表达量大小由高到低依次为心脏、脾脏、脑、肾脏、肠道、肌肉、肝脏。其中,心脏的表达量显著高于肝脏(P<0.01)和肌肉(P<0.05),脾脏、脑、肾脏及肠道的表达量高于肝脏(P<0.05)。在KLF6基因的mRNA表达量受到抑制后,BCAAs代谢酶(BCKDHb、ACADM、MCCC1、MCCC2、MUT、IVD)基因的mRNA表达量显著上升(P<0.05)。本研究为KLF6基因在鳜肌肉BCAAs代谢的调控机制研究提供了依据。 展开更多
关键词 转录因子 支链氨基酸 代谢酶 组织表达
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Parameter selection of support vector regression based on hybrid optimization algorithm and its application 被引量:9
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作者 Xin WANG Chunhua YANG +1 位作者 bin qin Weihua GUI 《控制理论与应用(英文版)》 EI 2005年第4期371-376,共6页
Choosing optimal parameters for support vector regression (SVR) is an important step in SVR. design, which strongly affects the pefformance of SVR. In this paper, based on the analysis of influence of SVR parameters... Choosing optimal parameters for support vector regression (SVR) is an important step in SVR. design, which strongly affects the pefformance of SVR. In this paper, based on the analysis of influence of SVR parameters on generalization error, a new approach with two steps is proposed for selecting SVR parameters, First the kernel function and SVM parameters are optimized roughly through genetic algorithm, then the kernel parameter is finely adjusted by local linear search, This approach has been successfully applied to the prediction model of the sulfur content in hot metal. The experiment results show that the proposed approach can yield better generalization performance of SVR than other methods, 展开更多
关键词 Support vector regression Parameters tuning Hybrid optimization Genetic algorithm(GA)
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Experimental study of transient pressure wave in the behind armor blunt trauma induced by different rifle bullets 被引量:6
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作者 Rui-guo Han Yong-jie Qu +3 位作者 Wen-min Yan bin qin Shu Wang Jian-zhong Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第4期900-909,共10页
Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of BABT.Comparison of pressure wave i... Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of BABT.Comparison of pressure wave in the gelatin behind armor for different rifle bullets is lacking.The aim of this study was to observe dynamic changes in pressure wave induced by ballistic blunt impact on the armored gelatin block and to compare the effects of bullet type on the parameters of the transient pressure wave.The gelatin blocks protected with National Institute of Justice(NIJ) class III bulletproof armor were shot by three types of rifle bullet with the same level of impact energy.The transient pressure signals at five locations were recorded with pressure sensors and three parameters(maximum pressure,maximum pressure impulse,and the duration of the first positive phase) were determined and discussed.The results indicated that the waveform and the twin peak of transient pressure wave were not related to the bullet type.However,the values of pressure wave's parameters were significantly affected by bullet type.Additionally,the attenuation of pressure amplitude followed the similar law for the three ammunitions.These findings may be helpful to get some insight in the BABT and improve the structure design of bullet. 展开更多
关键词 Behind armor blunt trauma Ballistic gelatin Pressure wave Body armor
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分子筛限域单位点钴体系催化芳香族化合物C-H键自调节高效氧化
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作者 党健 李玮杰 +3 位作者 秦斌 柴玉超 武光军 李兰冬 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期133-142,共10页
通过芳香族化合物的碳-氢键活化与选择氧化,可以将廉价芳香烃类原料转化为高附加值含氧产品,因此,该反应在基础研究和工业生产中均受到广泛关注.传统的苯乙酮生产工艺存在毒性底物使用、催化剂回收困难、反应条件苛刻以及产物收率低等问... 通过芳香族化合物的碳-氢键活化与选择氧化,可以将廉价芳香烃类原料转化为高附加值含氧产品,因此,该反应在基础研究和工业生产中均受到广泛关注.传统的苯乙酮生产工艺存在毒性底物使用、催化剂回收困难、反应条件苛刻以及产物收率低等问题.通过大量的研究探索,科研人员进一步改进其生产工艺,利用环烷酸钴作为均相催化剂,实现了无溶剂条件下分子氧直接选择氧化乙苯生成苯乙酮.相比均相催化,多相催化在催化剂回收和产物分离方面具有优势,更适合工业化生产.因此,开发用于乙苯选择氧化制苯乙酮的高效稳定多相催化体系非常重要,但具有较大挑战.本文采用原位配体保护的水热合成法将钴配合物(钴-二乙烯三胺)封装在Y型分子筛中,并经进一步焙烧去除配体成功制得Co@Y分子筛催化剂.在无溶剂、无添加剂的条件下,单位点Co作为Co@Y分子筛催化剂的活性位点可催化乙苯选择氧化生成苯乙酮.X射线粉末衍射、透射电镜、紫外可见光吸收光谱和固体核磁共振谱等结果表明,该单位点Co(Co^(2+))通过与骨架氧原子作用稳定限域在Y型分子筛中.为明确Co@Y分子筛催化剂中单位点Co在乙苯氧化反应中所起的重要作用,本文还对比了不同后合成方法所制备的Y分子筛(Co/Y,Co-Y)催化剂及工业环烷酸钴催化剂的催化性能.结果表明,在相同反应条件下,Co@Y分子筛催化剂表现出最高的催化性能,也说明在乙苯氧化反应过程中Co@Y分子筛催化剂的单位点Co有别于上述其他催化剂的活性位点.此外,在Co@Y催化剂热过滤实验中未检测出Co物种浸出,表明Co@Y分子筛催化乙苯氧化反应为多相催化过程,并且在多次循环测试后,Co@Y催化剂结构和反应活性均未发生明显变化.这两项实验均表明Co@Y催化剂具有高稳定性.值得注意的是,在乙苯氧化反应过程中观察到自加速现象,为此进行了对比实验(添加苯甲醛或1-苯乙醇的对比实验)和反应动力学分析.结果表明,痕量苯甲醛或1-苯乙醇的加入会显著改变Co@Y催化剂在乙苯氧化反应中的催化行为,痕量苯甲醛的加入可将反应表观活化能从69.7降至53.7 kJ/mol.本文也通过第一性原理密度泛函理论(DFT)计算系统研究了Co@Y分子筛催化剂单位点Co处乙苯选择氧化反应机理及反应过程中自加速现象产生的原因.DFT计算结果结合上述对比实验和反应动力学分析结果表明,加入痕量苯甲醛或者1-苯乙醇后部分乙苯会直接氧化生成苯乙酮,而非通过乙苯→1-苯乙醇→苯乙酮的途径生成苯乙酮.DFT计算结果也阐明反应过程中自加速现象的产生源于单位点Co处活性氧物种(O^(*))的生成.该活性氧物种在乙苯、苯甲醛和1-苯乙醇的氧化途径中均能自发生成,并且该物种类似“引发剂”促使后续更多链式反应的发生,在乙苯氧化反应过程中具有非常重要的作用.综上所述,本文为理解芳香族化合物碳-氢键选择氧化实验现象与催化作用机制提供了有益见解,可为理性设计开发更高效的催化剂提供新思路. 展开更多
关键词 碳-氢键活化 多相催化 Co@Y分子筛催化剂 自加速 活性氧物种
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Heterostructured Mn_(3)O_(4)-MnS Multi-Shelled Hollow Spheres for Enhanced Polysulfide Regulation in Lithium-Sulfur Batteries 被引量:4
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作者 bin qin Qun Wang +8 位作者 Weiqi Yao Yifei Cai Yuhan Chen Pengcheng Wang Yongchun Zou Xiaohang Zheng Jian Cao Junlei Qi Wei Cai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期436-444,共9页
Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and... Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and sluggish kinetics of polysulfide in lithium-sulfur(Li-S)batteries.However,a single strategy can only take limited effect.Modulating catalytic hosts with synergistic effects are urgently desired.Herein,Mn_(3)O_(4)-MnS heterogeneous multi-shelled hollow spheres are meticulously designed by controlled sulfuration of Mn2O3 hollow spheres,and then applied as advanced encapsulation hosts for Li-S batteries.Benefiting from the separated spatial confinement by hollow multi-shelled structure,ample exposed active sites and built-in electric field by heterogeneous interface,and synergistic effects between Mn_(3)O_(4)(strong adsorption)and MnS(fast conversion)components,the assembled battery achieves prominent rate capability and decent cyclability(0.016%decay per cycle at 2 C,1000 cycles).More crucially,satisfactory areal capacity reaches up to 7.1 mAh cm^(-2)even with high sulfur loading(8.0 mg cm^(-2))and lean electrolyte(E/S=4.0 pL mg^(-1))conditions.This work will provide inspiration for the rational design of hollow multi-shelled heterostructure for various electrocatalysis applications. 展开更多
关键词 ELECTROCATALYST heterojunction host hollow multi-shelled structure Li-S battery Mn_(3)O_(4)-MnS
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The underlying mechanism of variety–water–nitrogen–stubble damage interactions on yield formation in ratoon rice with low stubble height under mechanized harvesting 被引量:3
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作者 Jingnan Zou Ziqin Pang +11 位作者 Zhou Li Chunlin Guo Hongmei Lin Zheng Li Hongfei Chen Jinwen Huang Ting Chen Hailong Xu bin qin Puleng Letuma Weiwei Lin Wenxiong Lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期806-823,共18页
Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary ... Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary bud sprouting and yield formation in ratoon rice. This study used widely recommended conventional rice Jiafuzhan and hybrid rice Yongyou 2640 as the test materials to conduct a four-factor block design field experiment in a greenhouse of the experimental farm of Fujian Agricultural and Forestry University, China from 2018 to 2019.The treatments included fertilization and no fertilization, alternate wetting and drying irrigation and continuous water flooding irrigation, and plots with and without artificial crushing damage on the rice stubble. At the same time, a 13C stable isotope in-situ detection technology was used to fertilize the pot experiment. The results showed significant interactions among varieties, water management, nitrogen application and stubble status.Relative to the long-term water flooding treatment, the treatment with sequential application of nitrogen fertilizer coupled with moderate field drought for root-vigor and tiller promotion before and after harvesting of the main crop, significantly improved the effective tillers from low position nodes. This in turn increased the effective panicles per plant and grains per panicle by reducing the influence of artificial crushing damage on rice stubble and achieving a high yield of the regenerated rice. Furthermore, the partitioning of 13C assimilates to the residual stubble and its axillary buds were significantly improved at the mature stage of the main crop, while the translocation rate to roots and rhizosphere soil was reduced at the later growth stage of ratooning season rice. This was triggered by the metabolism of hormones and polyamines at the stem base regulated by the interaction of water and fertilizer at this time. We therefore suggest that to achieve a high yield of ratoon rice with low stubble height under mechanized harvesting, the timely application of nitrogen fertilizer is fundamental,coupled with moderate field drying for root-vigor preservation and tiller promotion before and after the mechanical harvesting of the main crop. 展开更多
关键词 mechanized harvesting ratoon rice rice stubble yield attributes
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Dynamic compressive response of porcine muscle measured using a split Hopkinson bar system with a pair of PVDF force transducers 被引量:2
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作者 Yao-ke Wen Liang Xu +2 位作者 Ai-jun Chen Fang-dong Dong bin qin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期298-305,共8页
The classic metallic Split Hopkinson Pressure Bar(SHPB)cannot capture the transmitted signal accurately when measuring soft biological tissue,because of the very low wave impedance and strength of this material.So the... The classic metallic Split Hopkinson Pressure Bar(SHPB)cannot capture the transmitted signal accurately when measuring soft biological tissue,because of the very low wave impedance and strength of this material.So the dynamic compressive response of porcine muscle has been investigated by using a modified SHPB.The forces on both ends of the sample measured using Polyvinylidene fluor(PVDF)transducers were applied to calculate the stress in the specimen instead of the strain gauge signal on the transmitted bar.Moreover,a circular cardboard disk pulse shaper was applied for generating a suitable incident pulse to achieve stress equilibrium and constant strain rates in the specimens.Then,the dynamic mechanical properties of porcine muscle parallel and perpendicular to the fiber directions were measured,and the stress equilibrium process during loading was analyzed,as well as the inertia-induced extra stress being corrected.Furthermore,quasi-static tests were conducted at two different strain rates to investigate the strain rate dependence using a universal material testing machine.The results show that the stress-strain curves are sensitive to strain rate in the two different loading directions.The compressive stress perpendicular to the fiber direction is stiffer than that parallel to the fiber direction.In addition,a strain rate-dependent constitutive model was developed based on the mechanical response of the muscle at different strain rates and fitted to the experimental data.The results show that the overall fit is good,and the constitutive model could describe the muscle's dynamic mechanical properties. 展开更多
关键词 PVDF Hopkinson bar Porcine muscle Dynamic mechanical properties Constitutive model
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Design and development of the beamline for a proton therapy system 被引量:2
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作者 bin qin Xu Liu +8 位作者 Qu-Shan Chen Dong Li Wen-Jie Han Ping Tan Zhong-Qi Zhang Chong Zhou Ao-Te Chen Yi-Cheng Liao Wei Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第12期53-63,共11页
A proton therapy(PT)facility with multiple treatment rooms based on the superconducting cyclotron scheme is under development at Huazhong University of Science and Technology(HUST).This paper attempts to describe the ... A proton therapy(PT)facility with multiple treatment rooms based on the superconducting cyclotron scheme is under development at Huazhong University of Science and Technology(HUST).This paper attempts to describe the design considerations and implementation of the PT beamline from a systematic viewpoint.Design considerations covering beam optics and the influence of high-order aberrations,beam energy/intensity modulation,and beam orbit correction are described.In addition to the technical implementation of the main beamline components and subsystems,including the energy degrader,fast kicker,beamline magnets,beam diagnostic system,and beamline control system are introduced. 展开更多
关键词 Proton therapy BEAMLINE Beam optics Beam energy/intensity modulation
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Characteristics of early gastric tumors with different differentiation and predictors of long-term outcomes after endoscopic submucosal dissection 被引量:2
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作者 Hong-Yi Zhu Jie Wu +7 位作者 Yuan-Miao Zhang Fang-Lan Li Jin Yang bin qin Jiong Jiang Ning Zhu Meng-Yao Chen Bai-Cang Zou 《World Journal of Gastroenterology》 SCIE CAS 2024年第14期1990-2005,共16页
BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological char... BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological characteristics of gastric mucosal tumors with different differentiation degrees and the influencing factors of long-term ESD efficacy may have certain significance for revealing the development of gastric cancer and ESD.AIM To analyze the features of gastric mucosal tumors at different differentiation levels,and to explore the prognostic factors of ESD.METHODS We retrospectively studied 301 lesions in 285 patients at The Second Affiliated Hospital of Xi'an Jiaotong University from 2014 to 2021,according to the latest Japanese guidelines(sixth edition),and divided them into low-grade intrae-pithelial neoplasia(LGIN),high-grade intraepithelial neoplasia(HGIN),and computed tomography at 3,6 and 12 months after ESD.We compared clinicopathologic characteristics,ESD efficacy,and complications with different degrees of differentiation,and analyzed the related factors associated with ESD.RESULTS HGIN and differentiated carcinoma patients were significantly older compared with LGIN patients(P<0.001)and accounted for more 0-IIc(P<0.001),atrophic gastritis was common(P<0.001),and irregular microvascular patterns(IMVPs)and demarcation lines(DLs)were more obvious(P<0.001).There was more infiltration in the undifferentiated carcinoma tissue(P<0.001),more abnormal folds and poorer mucosal peristalsis(P<0.001),and more obvious IMVPs,irregular microsurface patterns and DLs(P<0.05)than in the LGIN and HGIN tissues.The disease-free survival rates at 2,5,and 8 years after ESD were 95.0%,90.1%,and 86.9%,respectively.Undifferen-tiated lesions(HR 5.066),white moss(HR 7.187),incomplete resection(HR 3.658),and multiple primary cancers(HR 2.462)were significantly associated with poor prognosis.CONCLUSION Differentiations of gastric mucosal tumors have different epidemiological and endoscopic characteristics,which are closely related to the safety and efficacy of ESD. 展开更多
关键词 Gastric mucosal epithelial neoplasia Differentiated early gastric cancer Undifferentiated early gastric cancer Endoscopic submucosal dissection Long-term outcomes
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Decreased expression of gastrokine 1 in gastric mucosa of gastric cancer patients 被引量:1
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作者 Xiao-Yan Guo Lei Dong +2 位作者 bin qin Jiong Jiang A-Meng Shi 《World Journal of Gastroenterology》 SCIE CAS 2014年第44期16702-16706,共5页
AIM: To investigate the expression of gastrokine 1 (GKN1) in normal gastric mucosa, precancerous lesions and gastric cancer tissues, and to analyse its correlations with tumour site and pathological pattern.
关键词 Gastrokine 1 Gastric cancer Gastric mucosa EXPRESSION
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Spiro-based triphenylamine molecule with steric structure as a cathode material for high-stable all organic lithium dual-ion batteries
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作者 Liya Huang Zehao Yu +4 位作者 Liubin Wang bin qin Fengshi Cai Zhihao Yuan Zhiqiang Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期24-31,I0003,共9页
Redox p-type organic compounds are promising cathode materials for dual-ion batteries.However,the triphenylamine-based polymers usually with agglomerate and intertwined molecular chain nature limit the maximum reactio... Redox p-type organic compounds are promising cathode materials for dual-ion batteries.However,the triphenylamine-based polymers usually with agglomerate and intertwined molecular chain nature limit the maximum reaction of their active sites with large-sized anions.Herein,we demonstrate the application of a small molecule with rigid spirofluorene structu re,namely 2,2’,7,7’-tetrakis(diphenylamine)-9,9’-spirobifluorene(Spiro-TAD),as a cathode material for lithium dual-ion batteries.The inherent sterical structure endows the Spiro-TAD with good chemical stability and large internal space for fast diffusion kinetics of anions in the organic electrolyte.As a result,the Spiro-TAD electrode shows significant insolubility and less steric hindrance,and gives a high actual capacity of 109 mA h g^(-1)(active groups utilization ratio approximately 100%) at 50 mA g^(-1)with a high discharge voltage of 3.6 V(vs.Li+/Li),excellent rate capability(60 mA h g^(-1)at 2000 mA g^(-1)) and extremely stable cycling life(98.4% capacity retention after 1400 cycles at 500 mA g^(-1)) in half cells.Such good electrochemical performance is attributed to the robust and rapid adsorption/desorption of ClO4-anions,which can be proved by the in-situ FTIR and XPS.Moreover,an all-organic lithium dual-ion battery(a-OLDIBs) is constructed using the Spiro-TAD as cathode and 3,4,9,10-Perylenetetracarboxylic diimide(PTCDI) as anode and displays long-term cycling performance of 87.5 mA h g^(-1)after 800 cycles.This study will stimulate further developments in designing all organic battery systems. 展开更多
关键词 Spiro-basedmolecule Cathodematerial P-typeorganiccompounds Longcycling life All organic lithiumdual-ionbatteries
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