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单轴拉伸下NEPE固体推进剂细观结构演化行为研究

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含能材料 2024年第2期32卷 175-182页

作者：李世奇强洪夫陈铁铸王学仁王哲君王广火箭军工程大学智剑实验室陕西西安710025 火箭军工程大学导弹工程学院陕西西安710025

为了分析硝酸酯增塑聚醚(Nitrate Ester Plasticized Polyether,NEPE)推进剂在单轴准静态拉伸载荷下细观结构演化行为,基于Micro⁃CT对拉伸过程中NEPE推进剂开展了原位观测试验,对NEPE推进剂中高氯酸铵(AP)颗粒和初始缺陷的尺寸、形状等... 详细信息

为了分析硝酸酯增塑聚醚(Nitrate Ester Plasticized Polyether,NEPE)推进剂在单轴准静态拉伸载荷下细观结构演化行为,基于Micro⁃CT对拉伸过程中NEPE推进剂开展了原位观测试验,对NEPE推进剂中高氯酸铵(AP)颗粒和初始缺陷的尺寸、形状等细观结构特征进行了表征,获取了单轴拉伸过程中推进剂细观结构的失效过程,并采用孔隙率对NEPE推进剂细观损伤的变化规律进行了定量分析,基于NEPE推进剂细观尺度上结构的演变规律解释了宏观力学性能变化的原因。结果表明,NEPE推进剂初始缺陷尺寸小、体积占比低,平均值为0.12%。单轴准静态拉伸过程中,NEPE推进剂的细观失效过程主要包括孔洞形核、生长与汇聚3个阶段;AP颗粒的体积分数虽然低,但是由于容易脱湿通常成为细观损伤的起点;当AP发生一定程度脱湿后,奥克托今(HMX)也会出现明显的脱湿,在分析NEPE推进剂细观失效问题时应当考虑HMX脱湿行为的影响。大量细观缺陷的形核与生长是NEPE推进剂宏观力学性能进入非线性段的原因,而细观缺陷的不断汇聚使得宏观应力增加落后于应变增加的现象越来越明显。加载过程中孔隙率呈现出先缓慢增加再急剧增加最后增加趋于平缓的变化趋势,孔隙率的变化规律不仅能够定量地反映NEPE推进剂细观缺陷的演化阶段,与NEPE推进剂宏观力学性能的变化也具有一定的对应关系。

关键词： NEPE固体推进剂细观损伤单轴拉伸奥克托今脱湿

AFF1 and AFF4 differentially regulate the osteogenic differentiation of human MSCs

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Bone Research 2017年第3期5卷 207-216页

作者： Chen-chen Zhou Qiu-chan Xiong Xin-xing zhu Wen Du Peng Deng Xiao-bing Li Yi-zhou Jiang Shu-juan Zou Cun-yu Wang quan Yuan State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases West China Hospital of Stomatology Sichuan University Institute for Advanced Study Shenzhen University Laboratory of Molecular Signaling Division of Oral Biology and Medicine School of Dentistry and Broad Stem Cell Research Center UCLA Department of Orthodontics West China Hospital of Stomatology Sichuan University Department of Oral Implantology West China Hospital of Stomatology Sichuan University

AFF1 and AFF4 belong to the AFF （AF4/FMR2） family of proteins, which function as scaffolding proteins linking two different transcription elongation factors, positive elongation factor b （P-TEFb） and ELL1/2, in super elongation complexes （SECs）. Both AFF1 and AFF4 regulate gene transcription through elongation and chromatln remodeling. However, their function in the osteogenic differentiation of mesenchymal stem cells （MSCs） is unknown. In this study, we show that small interfering RNA （siRNA）-mediated depletion of AFF1 in human MSCs leads to increased alkaline phosphatase （ALP） activity, enhanced mineralization and upregulated expression of osteogenic-related genes. On the contrary, depletion of AFF4 significantly inhibits the osteogenic potential of MSCs. In addition, we confirm that overexpression of AFF1 and AFF4 differentially affects osteogenic differentiation in vitro and MSC-mediated bone formation in vivo. Mechanistically, we find that AFFI regulates the expression of DKK1 via binding to its promoter region. Depletion of DKK1 in HA-AFFl-overexpressing MSCs abrogates the impairment of osteogenic differentiation. Moreover, we detect that AFF4 is enriched in the promoter region of ID1. AFF4 knockdown blunts the BRE luciferase activity, SP7 expression and ALP activity induced by BMP2 treatment. In conclusion, our data indicate that AFF1 and AFF4 differentially regulate the osteogenic differentiation of human ***1 and AFF4 belong to the AFF （AF4/FMR2） family of proteins, which function as scaffolding proteins linking two different transcription elongation factors, positive elongation factor b （P-TEFb） and ELL1/2, in super elongation complexes （SECs）. Both AFFI and AFF4 regulate gene transcription through elongation and chromatln remodeling. However, their function in the osteogenic differentiation of mesenchymal stem cells （MSCs） is unknown. In this study, we show that small interfering RNA （siRNA）-mediated depletion of AFF1 in human MSCs leads to increased

关键词： AFF1 and AFF4 differentially regulate the osteogenic differentiation of human MSCs Figure PCR RT ALP

1972-2021年江苏省启东市肝癌发病年龄-时期-队列趋势分析

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中国肿瘤 2024年第6期33卷 430-438页

作者：朱健严永锋王军陈永胜丁璐璐张永辉徐源佑唐红萍陈建国启东市人民医院/启东肝癌防治研究所/南通大学附属启东医院江苏启东226200 南通市肿瘤医院/南通大学附属肿瘤医院江苏南通226361

[目的]分析江苏省启东市1972-2021年全人群肝癌发病变化趋势,评估其年龄、时期和队列效应。[方法]从启东市癌症登记病例数据库中提取1972-2021年肝癌发病登记资料,计算粗发病率、世界人口标化率(世标率)和平均年度变化百分比(AAPC)。采... 详细信息

[目的]分析江苏省启东市1972-2021年全人群肝癌发病变化趋势,评估其年龄、时期和队列效应。[方法]从启东市癌症登记病例数据库中提取1972-2021年肝癌发病登记资料,计算粗发病率、世界人口标化率(世标率)和平均年度变化百分比(AAPC)。采用年龄-时期-队列模型分析启东市1972-2021年肝癌发病率的年龄、时期和队列效应。[结果]启东市1972-2021年共计发生肝癌36127例,世标率从1972-1981年的56.93/10万下降至2012-2021年的29.87/10万。其中男性26710例,世标率从1972-1981年的91.06/10万下降至2012-2021年的44.27/10万;女性9417例,世标率从1972-1981年的26.28/10万下降至2012-2021年的16.21/10万。50年世标率的AAPC为-1.47%(男性-1.67%,女性-1.02%)(P均<0.001)。净漂移值为-2.65%(男性-2.95%,女性-2.10%),均呈下降趋势;局部漂移表现为15~59岁年龄段(男性15~64岁,女性15~54岁)呈下降趋势。年龄效应表现为男性曲线为双峰型,第一峰在45~49岁年龄组(发病率为216.35/10万),第二峰在80岁及以上年龄组(发病率为186.35/10万);女性为单峰型,最高峰在75~79岁年龄组(发病率为108.75/10万)。时期效应以1992-1996年为参考组,1972-1976年RR为2.10(男性2.20,女性1.99),后逐渐下降,至2017-2021年至最低点,RR为0.50(男性0.46,女性0.62)。出生队列效应以1952-1956年出生组为参考组,1932-1936年为最高点,RR为1.18,后逐渐下降,至1982年后一直处于低位。APC模型的Waldχ2检验结果显示,男女合计、男性和女性肝癌发病风险的年龄效应、时期效应和出生队列效应趋势变化差异均具有统计学意义(P均<0.001)。[结论]启东肝癌发病率下降趋势明显,年龄、时期和队列均是影响启东肝癌发病的主要因素,老年人群及男性中年人群是肝癌防控重点关注对象,同时需继续监测肝癌发生的高危因子。

关键词：肝癌发病率趋势年龄-时期-队列模型江苏

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铊短期暴露对SBR活性污泥性能的影响

中国环境科学 2024年第7期44卷 3780-3785页

作者：赵晓静罗远玲吴红辉丁雨葶向珂逸黄骏国高嘉妮贾美莹胡新将朱健王平徐海音中南林业科技大学环境科学与工程学院湖南长沙410004 长沙环境保护职业技术学院湖南长沙410018 湖南大学湖南长沙410082

以序批式活性污泥(SBR)工艺为例,从脱氮除磷性能、微生物及酶活性等方面研究了Tl暴露浓度对活性污泥性能的短期扰动及其恢复行为.结果表明:活性污泥的脱氮除磷性能和COD去除均易受Tl的影响.当Tl为500µg/L时,脱氮除磷被抑制,但Tl暴露消... 详细信息

以序批式活性污泥(SBR)工艺为例,从脱氮除磷性能、微生物及酶活性等方面研究了Tl暴露浓度对活性污泥性能的短期扰动及其恢复行为.结果表明:活性污泥的脱氮除磷性能和COD去除均易受Tl的影响.当Tl为500µg/L时,脱氮除磷被抑制,但Tl暴露消除后,性能可恢复.而当Tl为1000µg/L时,尽管除磷效率可恢复至65%,但脱氮过程完全被抑制且不可逆.低浓度Tl提高了COD去除率且高浓度Tl对COD去除的影响是可逆的.此外,200µg/L的Tl提高了微生物活性,但1000µg/L的Tl会导致过氧化氢酶和超氧化物歧化酶相对产量分别降低至71.9%和30.8%,极大抑制了微生物活性;比耗氧速率对Tl的存在与消失均很敏感,可作为污水处理厂Tl暴露的指示指标.傅里叶红外光谱和X射线光电子能谱表征结果表明,Tl与游离态胞外聚合物的羟基结合或由Tl^(+)氧化成Tl^(3+),可能是活性污泥降低Tl对其细胞毒性的作用机制.因此Tl短期暴露时,需增强活性污泥的脱氮除磷性能并强化其除Tl能力,以确保污水处理厂稳定运行.本研究揭示了Tl短期暴露对活性污泥系统的潜在影响并提出了应对措施.

关键词：铊 SBR 脱氮除磷酶活性

Manipulating the Flipping of Water Dipoles in Carbon Nanotubes

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Chinese Physics Letters 2019年第10期36卷 17-21页

作者： Dang-Xin Mao Xiao-Gang Wang Guo-quan Zhou Song-Wei Zeng Liang Chen jun-Lang Chen Chao-Qing Dai Department of Optical Engineering Zhejiang A&F UniversityHangzhou 311300 School of Information and Industry Zhejiang A&F UniversityHangzhou 311300

Flipping of water dipoles in carbon nanotubes is of great importance in many physical and biological applications,such as signal amplification,molecular switches and *** of these applications,understanding and inhibiting the non-negligible thermal noise is ***,we use molecular dynamics simulations to show that the flipping frequency of water dipoles increases with the rising temperature,and the thermal noise can be suppressed by imposed charges and external uniform electric ***,the water dipoles flip periodically between two equiprobable and stable states under alternating electric *** two stable states may be adopted to store 0 and 1 bits for memory storage or molecular computing.

关键词： noise negligible Carbon

Spontaneous fracture of a titanium mesh cranioplasty implant in a child: A case report

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World Journal of Clinical Cases 2023年第7期11卷 1593-1599页

作者： Rui Zhang Zhe Gao Yong-Jie zhu Xin-Fa Wang Gang Wang jun-Ping He Department of Neurosurgery Nanjing Children's HospitalNanjing Medical UniversityNanjing 21000Jiangsu ProvinceChina

BACKGROUND Titanium mesh cranioplasty is often performed after decompressive *** fracture of the titanium prosthesis is an extremely rare postoperative ***,we report a 10-year-old boy who presented with a spontaneous fracture of titanium mesh without antecedent head *** SUMMARY A 10-year-old boy presented with a 1-wk history of a tender bulge over the left temporo-parieto-occipital *** had undergone a temporo-parieto-occipital titanium mesh cranioplasty 26 mo *** denied antecedent head *** tomography disclosed a perpendicular fissure in the titanium mesh,suggesting a diagnosis of spontaneous titanium mesh *** underwent a second temporo-parieto-occipital cranioplasty and made an uneventful ***-dimensional modeling and finite element analyses were used to explore potential risk factors of titanium mesh *** We report a case of spontaneous fracture of a titanium mesh cranioplasty *** current case and literature review indicate that titanium mesh implants should be well-anchored to the base of bony defects to prevent fatigue-induced fractures.

关键词： Cranioplasty Prosthesis fracture Spontaneous fracture Titanium Case report

New discovery of high-affinity SARS-CoV-2 spike S2 protein binding peptide selected by PhIP-Seq

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Virologica Sinica 2022年第5期37卷 758-761页

作者： Mengyuan Chen Shuizhen He Hualong Xiong Dongxu Zhang Shaojuan Wang Wangheng Hou Xiaomei zhu Jin Wang Yang Huang Congming Hong Yubin Wu Ruoyao Qi Tianying Zhang quan Yuan Tingdong Li Yixin Chen Shiyin Zhang Shengxiang Ge jun Zhang Ningshao Xia State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics National Institute of Diagnostics and Vaccine Development in Infectious DiseasesSchool of Public HealthXiamen UniversitySouth Xiang'an RoadXiamen361102China Xiamen Haicang Hospital Haiyu RoadXiamen361026China School of Life Sciences Xiamen UniversitySouth Xiang'an RoadXiamen361102China

Dear Editor,Theworld had suffered pandemics of COVID-19 caused by *** the time ofwriting,COVID-19 is still widely spreading inmany countries and regions,and by june 14,2022,totally 532,887,351 cases,including 6,307,021 deaths,were reported globally(WHO,https://***/table).Powerful measures,such as prophylactic and therapeutic interventions against the virus,are in urgent need for COVID-19 control and *** spike protein,which is expressed on the virus surface,is the key determinant of viral-host interaction(Ng et al.,2021)and mediates the virus entry.

关键词： PhIP totally

General construction of lithiophilic 3D skeleton for dendrite-free lithium metal anode via a versatile MOF-derived route

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Science China Materials 2022年第2期65卷 337-348页

作者： Liyan Zeng Ting Zhou Xijun Xu Fangkun Li Jiadong Shen Dechao Zhang jun Liu Min zhu School of Materials Science and Engineering and Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials South China University of TechnologyGuangzhou 510641China

The pursuit of high-mileage models results in the recurrence of lithium metal batteries(LMBs)to researchers’***,the lithium(Li)metal anode for LMBs undergoes the uncontrollable formation of Li dendrites and infinite volume change during cycling,impeding its practical *** overcome these challenges,we developed a metal-organic framework(MOF)-derived pathway to construct lithiophilic three-dimensional(3D)skeleton using different substrates(e.g.,carbon cloth(CC)and Cu mesh)for dendrite-free lithium metal *** a typical example,the MOF-derived ZnO/nitrogen-doped carbon(NC)nanosheet-modified 3D CC was well-constructed as a lithiophilic hierarchical host(CC@ZnO/NC@Li)for molten Li *** from the lithiophilic N-functional groups and LiZn alloy,the synthesized CC@ZnO/NC@Li composite anode promoted the uniform distribution of Li,resulting in a dendrite-free ***,the 3D conductive carbon skeleton enhanced the reaction kinetics and buffered the volume change of the *** CC@ZnO/NC@Li composite anode presented a prolonged lifespan of over 1000 cycles at 5 mA cm^(−2) with a low overpotential of 19 *** with a LiFePO_(4) cathode,the CC@ZnO/NC@Li composite anode also exhibited superior electrochemical properties in the full-cell *** versatile strategy may open up the channel of designing multi-functional lithiophilic 3D hosts for the Li metal anode.

关键词： dendrite-free lithium anode 3D lithiophilic host MOF-derived ZnO/NC nanosheets lithium metal batteries

Carcinosarcoma of the deep lobe of the parotid gland in the parapharyngeal region:A case report

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World Journal of Clinical Cases 2023年第31期11卷 7663-7672页

作者： Yue-Yang Tang Gui-quan zhu Zhi-Jian Zheng Li-Hong Yao Zi-Xin Wan Xin-Hua Liang Ya-Ling Tang Department of Oral Pathology West China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases West China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Oral and Maxillofacial Surgery West China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Salivary carcinosarcoma is an extremely rare tumor containing both malignant epithelial and mesenchymal *** article reports a rare case of carcinosarcoma with salivary duct carcinoma and osteosarcoma as the tumor *** clinicopathological characteristics,treatment,and prognosis are discussed in conjunction with the *** SUMMARY A 48-year-old man presented with a complaint of a mass in the right parotid *** was first considered for assessment by fine-needle aspiration *** examination revealed a mass measuring approximately 4 cm×3.5 cm×3 *** mass,the whole lobe of the right parotid gland,and the right mandible were completely removed during *** histopathology confirmed carcinosarcoma of the salivary *** A definite diagnosis of salivary gland carcinosarcoma can only be obtained after complete surgical resection.

关键词： Salivary gland tumor Carcinosarcoma Clinicopathology Fluorescence in situ hybridization Case report