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Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers 被引量:1
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作者 Kaiwen Lei Hao Wu +4 位作者 Jerry W Spears xi Lin xi wang Xue Bai Yanling Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1329-1337,共9页
This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.... This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein. 展开更多
关键词 IRON yellow-feathered broiler antioxidant function intestinal morphology tight junction protein
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Enhanced structural stability and durability in lithium-rich manganese-based oxide via surface double-coupling engineering
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作者 Jiayu Zhao Yuefeng Su +10 位作者 Jinyang Dong xi wang Yun Lu Ning Li Qing Huang Jianan Hao Yujia Wu Bin Zhang Qiongqiong Qi Feng Wu Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期274-283,共10页
Lithium-rich manganese-based oxides(LRMOs) exhibit high theoretical energy densities, making them a prominent class of cathode materials for lithium-ion batteries. However, the performance of these layered cathodes of... Lithium-rich manganese-based oxides(LRMOs) exhibit high theoretical energy densities, making them a prominent class of cathode materials for lithium-ion batteries. However, the performance of these layered cathodes often declines because of capacity fading during cycling. This decline is primarily attributed to anisotropic lattice strain and oxygen release from cathode surfaces. Given notable structural transformations, complex redox reactions, and detrimental interface side reactions in LRMOs, the development of a single modification approach that addresses bulk and surface issues is challenging. Therefore,this study introduces a surface double-coupling engineering strategy that mitigates bulk strain and reduces surface side reactions. The internal spinel-like phase coating layer, featuring threedimensional(3D) lithium-ion diffusion channels, effectively blocks oxygen release from the cathode surface and mitigates lattice strain. In addition, the external Li_(3)PO_(4) coating layer, noted for its superior corrosion resistance, enhances the interfacial lithium transport and inhibits the dissolution of surface transition metals. Notably, the spinel phase, as excellent interlayer, securely anchors Li_(3)PO_(4) to the bulk lattice and suppresses oxygen release from lattices. Consequently, these modifications considerably boost structural stability and durability, achieving an impressive capacity retention of 83.4% and a minimal voltage decay of 1.49 m V per cycle after 150 cycles at 1 C. These findings provide crucial mechanistic insights into the role of surface modifications and guide the development of high-capacity cathodes with enhanced cyclability. 展开更多
关键词 Lithium-ion battery Layered lithium-rich cathode Surface double-coupling engineering Lattice strain Oxygen release
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Effectiveness of onsite and online education in enhancing knowledge and use of human immunodeficiency virus pre-and postexposure prophylaxis
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作者 Ying Shao Mei Zhang +10 位作者 Li-Jun Sun Hong-Wei Zhang An Liu xi wang Ruo-Lei xin Jian-Wei Li Jiang-Zhu Ye Yue Gao Zhang-Li wang Zai-Cun Li Tong Zhang 《World Journal of Clinical Cases》 SCIE 2024年第22期5042-5050,共9页
BACKGROUND Enhancing awareness and use of pre-exposure prophylaxis(PrEP)and postexposure prophylaxis(PEP)is vital to curb human immunodeficiency virus(HIV)spread.High-risk behaviors prevalent among sexually transmitte... BACKGROUND Enhancing awareness and use of pre-exposure prophylaxis(PrEP)and postexposure prophylaxis(PEP)is vital to curb human immunodeficiency virus(HIV)spread.High-risk behaviors prevalent among sexually transmitted infection clinic outpatients underscore the need for increased PrEP/PEP education in this group.AIM To investigate the effects of both onsite and online health education on the knowledge of,and willingness to use,PrEP and PEP among individuals receiving PEP services.METHODS Participants were drawn from a cohort study on PEP service intervention at an STD/AIDS outpatient clinic in designated HIV/AIDS hospitals in Beijing,conducted from January 1 to June 30,2022.Health education was provided both onsite and online during follow-up.Surveys assessing knowledge of,and willingness to use,PrEP/PEP were administered at baseline and again at 24 wk post-intervention.RESULTS A total of 112 participants were enrolled in the study;105 completed the follow-up at week 24.The percentage of participants with adequate knowledge of,and willingness to use,PrEP significantly increased from 65.2%and 69.6%at baseline to 83.8%and 82.9%at the end of the intervention(both P<0.05).Similarly,those with adequate knowledge of,and willingness to use,PEP increased from 74.1%and 77.7%at baseline to 92.4%and 89.5%at week 24(P<0.05).Being between 31 years and 40 years of age,having a postgraduate degree or higher,and reporting a monthly expenditure of RMB 5000 or more were found to be significantly associated with knowledge of PrEP and PEP(both P<0.05).CONCLUSION The findings show that both onsite and online health education significantly improved the knowledge of,and increased willingness to use,PrEP and PEP in individuals utilizing PEP services. 展开更多
关键词 Human immunodeficiency virus Pre-exposure prophylaxis Post-exposure prophylaxis Health education INTERVENTION
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ChatGPT技术在生物医药领域的应用潜力与风险 被引量:2
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作者 王茜 李东巧 刘细文 《中国科学基金》 CSSCI CSCD 北大核心 2024年第1期200-210,共11页
本文系统梳理了ChatGPT的发展历程与现状,分析ChatGPT技术与生物医药领域的耦合情况。从知识创新与模型创新两个维度,划分生物医药领域ChatGPT技术应用的类型,并分析其应用焦点、应用场景和特征;从科学研究与消费终端应用的角度阐述各项... 本文系统梳理了ChatGPT的发展历程与现状,分析ChatGPT技术与生物医药领域的耦合情况。从知识创新与模型创新两个维度,划分生物医药领域ChatGPT技术应用的类型,并分析其应用焦点、应用场景和特征;从科学研究与消费终端应用的角度阐述各项ChatGPT技术类型在生物医药领域中的应用价值;剖析各项ChatGPT技术类型在生物医药领域中存在的潜在风险。ChatGPT技术将加快生物医药领域的研究与服务,扩大而非取代研究人员的专业知识。未来应加强微调挖掘型GPT工具与部署型服务设施的建设,推动ChatGPT技术在生物医药领域的有效应用。 展开更多
关键词 ChatGPT 生物医药 应用场景 潜在风险 人工智能
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高级别胎儿型肺腺癌并头皮转移1例 被引量:1
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作者 德吉央宗 边玛措 +1 位作者 王玺 王寒 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第2期147-151,共5页
胎儿型肺腺癌(fetal adenocarcinoma of the lung,FLAC)是一种罕见的肺部肿瘤。FLAC分为低级别FLAC(low-grade FLAC,L-FLAC)和高级别FLAC(high-grade FLAC,H-FLAC),两者在临床病理特征、生物学行为和临床结局方面有所不同。大多数H-FLA... 胎儿型肺腺癌(fetal adenocarcinoma of the lung,FLAC)是一种罕见的肺部肿瘤。FLAC分为低级别FLAC(low-grade FLAC,L-FLAC)和高级别FLAC(high-grade FLAC,H-FLAC),两者在临床病理特征、生物学行为和临床结局方面有所不同。大多数H-FLAC患者是重度吸烟的中年人。本研究描述了1例罕见的非吸烟年轻男性患者,其最初表现为头顶肿块,最终被诊断为H-FLAC。本文旨在增进对FLAC的了解和认识,提高对该疾病的重视,以防止该疾病漏诊与误诊,加强早期识别、精准诊断,从而推进后续的有效治疗、改善预后。 展开更多
关键词 青年 胎儿型肺腺癌 头皮肿瘤 转移
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Experimental Study on the Repair Effect of Xianlinggubao Capsule on Osteoporotic Vertebral Compression Fracture in Rabbits
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作者 Lihong GUO Lizhu LIU +2 位作者 xi wang Heng LIAO Jingping MU 《Medicinal Plant》 2023年第6期64-66,70,共4页
[Objectives]To observe the effect of Xianlinggubao Capsule on osteoporotic vertebral compression fracture(OVCF)in rabbits and the influence mechanism of the repair of fractures.[Methods]Female June age 30 rabbits were... [Objectives]To observe the effect of Xianlinggubao Capsule on osteoporotic vertebral compression fracture(OVCF)in rabbits and the influence mechanism of the repair of fractures.[Methods]Female June age 30 rabbits were randomly divided into control group,model control group and Xianlinggubao group.After bilateral ovariectomy,the model control group and Xianlinggubao group were injected with dexamethasone continuously for 4 weeks,and then the OVCF compound model was established by surgery.The Xianlinggubao group was treated with Xianlinggubao at a dose of 300 mg/(kg·d)for 60 d,while the blank control group and the model control group were treated with the same amount of normal saline for 60 d.The number of blood vessels and the expression of bone morphogenetic protein-2(BMP-2)were detected by immunohistochemical staining and the bone mineral density(BMD)in the callus of the third lumbar fracture area of rabbits was measured.The content of serum phosphorus(P),alkaline phosphatase(ALP)and total calcium(TCa)in rabbit venous blood were measured by automatic biochemical analyzer.The content of vascular endothelial growth factor(VEGF)and platelet-derived growth factor(PDGF)in rabbit venous blood were measured by ELISA kit.[Results]The number of blood vessels and the expression of BMP-2 in the callus of the third lumbar fracture area of rabbits was high in Xianlinggubao group,the content of serum P,ALP,TCa,VEGF and PDGF was obviously increased,BMD was obviously increased,the bone microstructure of the third lumbar vertebrae fracture area of rabbits was basically restored.Compared with the model control group(P<0.05),the difference was statistically significant.[Conclusions]Xianlinggubao Capsule can increase calcium and phosphorus deposition,promote the formation of blood vessels in the fracture area of OVCF in rabbits,and have a strong repair effect on OVCF in rabbits. 展开更多
关键词 RABBIT Xianlinggubao Capsule OSTEOPOROSIS Compound model of vertebral compression fracture REPAIR
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基于岩溶三维地质模型的桩基承载力特性研究 被引量:3
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作者 奚望 边林松 +3 位作者 梁鹏飞 李伟 向成韬 周博 《土木工程与管理学报》 2024年第1期32-38,57,共8页
本文依托中铁十九局集团有限公司岑大公路YTHJ4标桥梁桩基项目,通过Civil 3D软件建立了三维地质模型;并介绍了桩基作用下溶洞两种不同的破坏模式;然后采用基于FLAC 3D数值分析软件的单因子变量法分析了不同溶洞顶板厚度、顶板跨度、洞... 本文依托中铁十九局集团有限公司岑大公路YTHJ4标桥梁桩基项目,通过Civil 3D软件建立了三维地质模型;并介绍了桩基作用下溶洞两种不同的破坏模式;然后采用基于FLAC 3D数值分析软件的单因子变量法分析了不同溶洞顶板厚度、顶板跨度、洞高、溶洞中心偏离桩轴线距离等对嵌岩桩承载力特性(极限承载力、极限侧摩阻力、桩土相对滑移距离等)的影响。研究结果表明:溶洞顶板是影响桩基极限承载力的主要因素;溶洞极限状态下的破坏模式强烈依赖于溶洞顶板厚度、顶板跨度和岩体力学性质;当溶洞顶板厚度达到三倍的桩径时,桩侧摩阻力可完全发挥;溶洞顶板跨度和偏心距离对桩基承载力特性的影响存在一个稳定点。这些研究结论为岩溶地区的嵌岩桩设计提供了一定的参考依据,进一步丰富了岩溶地区桩基设计理念。 展开更多
关键词 溶洞 嵌岩桩 三维地质模型 应力扩散 承载力特性
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氮化硼/磷杂菲三嗪化合物阻燃导热聚碳酸酯复合材料的制备及其性能研究
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作者 张俊 奚望 +4 位作者 钱立军 周凤帅 邱勇 王靖宇 张志鹏 《中国塑料》 CAS CSCD 北大核心 2024年第3期31-37,共7页
基于氮化硼(BN)/磷杂菲三嗪化合物(TAD)构建了阻燃导热聚碳酸酯(PC)复合材料,并对其阻燃性能和导热性能进行了研究。结果表明,BN/TAD阻燃导热复合体系能够有效提高PC复合材料的阻燃性能,当BN添加量为20%,TAD含量为3%时,PC/20BN/3TAD复... 基于氮化硼(BN)/磷杂菲三嗪化合物(TAD)构建了阻燃导热聚碳酸酯(PC)复合材料,并对其阻燃性能和导热性能进行了研究。结果表明,BN/TAD阻燃导热复合体系能够有效提高PC复合材料的阻燃性能,当BN添加量为20%,TAD含量为3%时,PC/20BN/3TAD复合材料的垂直燃烧测试达到UL 94 V-0级,极限氧指数达到35.1%;通过锥形量热仪测试,证明了BN/TAD阻燃导热复合体系能够有效降低热释放速率峰值、总热释放量、有效燃烧热等性能参数,并且二者在凝聚相中可以发挥出色的协同成炭效果,赋予PC复合材料优异的阻燃特性;从导热性能测试方面来看,BN/TAD阻燃导热复合体系的导热系数较纯PC相比提高了320%,获得了兼具优异阻燃特性和出色导热性能的PC复合材料。 展开更多
关键词 聚碳酸酯 阻燃 导热性 协同成炭
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基于Doehlert Matrix的全贯流泵装置定转子进出流间隙优化设计
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作者 刘健峰 奚望 +2 位作者 陆伟刚 陆雯 杨晨霞 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期170-180,共11页
全贯流泵是一种新型的机电-水泵一体式贯流泵,然而其在运行时存在定转子间隙回流,扰乱了叶轮内的流场分布,导致泵装置产生能量损失、压力波动和噪声等问题,影响泵站的正常运行。通过数值模拟和模型试验研究全贯流泵装置定转子间隙流的... 全贯流泵是一种新型的机电-水泵一体式贯流泵,然而其在运行时存在定转子间隙回流,扰乱了叶轮内的流场分布,导致泵装置产生能量损失、压力波动和噪声等问题,影响泵站的正常运行。通过数值模拟和模型试验研究全贯流泵装置定转子间隙流的水力特性,结合Doehlert Matrix设计-响应面优化法对其定转子进、出流间隙结构进行优化设计,揭示全贯流泵装置定转子进、出流间隙结构对泵装置性能的影响机理,并得到最终优化的折角式定转子进、出流间隙结构方案为:外侧延伸段长度t1为4.921r,外侧收缩段长度x1为0.624r,内侧延伸段长度t2为3.655r,内侧收缩段长度x2为1.6r(r为定转子间隙宽度),使得全贯流泵装置扬程和效率分别提升约10.3%和5.2%。 展开更多
关键词 全贯流泵 定转子间隙流 Doehlert Matrix设计
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Y形导流墩对侧向进水泵站进水前池流态影响
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作者 张雄伟 奚斌 +5 位作者 奚望 王欣昱 徐健 吉睿 连延续 宋梓豪 《水电能源科学》 北大核心 2024年第10期144-148,共5页
侧向进水泵站前池易形成回流或漩涡,造成进水流态分布不均等现象。由于Y形导流墩有较好的分流效果,为解决侧向进水泵站进水偏流、横向流速过大问题,对Y形导流墩位置和几何参数进行研究。基于正交试验法设计试验方案,构建5因素5水平的正... 侧向进水泵站前池易形成回流或漩涡,造成进水流态分布不均等现象。由于Y形导流墩有较好的分流效果,为解决侧向进水泵站进水偏流、横向流速过大问题,对Y形导流墩位置和几何参数进行研究。基于正交试验法设计试验方案,构建5因素5水平的正交试验表,并对各方案进行数值模拟。以流速均匀度作为评价指标进行极差分析,结果表明Y形导流墩的位置设计对进水前池的影响大于几何参数的选定,并确定最优方案设计参数,使A-A断面轴向流速均匀度提升7.17%,横向流速加权平均角提升2%,进水前池流态改善明显。为使Y形导流墩更具有普适性,提出无量纲化参数,该参数可为此类型泵站工程Y形导流墩使用设计提供一定的参考。 展开更多
关键词 正交试验法 Y形导流墩 侧向进水 几何参数
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Monaco计划系统中Conformality函数对宫颈癌容积旋转调强计划的影响
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作者 郗旺 赵媛媛 +2 位作者 王小秋 陈晓南 何瑞龙 《生物医学工程与临床》 CAS 2024年第4期515-520,共6页
目的 探讨Monaco计划系统中Conformality函数的不同参数值对计划质量的影响。方法 选择15例宫颈癌患者,年龄46~74岁,中位年龄51岁。分别采用Conformality函数参数值为0.25、0.50、0.75、1.00,以及不加函数设计容积旋转调强放射治疗(VMAT... 目的 探讨Monaco计划系统中Conformality函数的不同参数值对计划质量的影响。方法 选择15例宫颈癌患者,年龄46~74岁,中位年龄51岁。分别采用Conformality函数参数值为0.25、0.50、0.75、1.00,以及不加函数设计容积旋转调强放射治疗(VMAT)计划,评估靶区及危及器官(OAR)剂量学参数和20 Gy、30 Gy、40 Gy等剂量线的体积和计划执行效率。结果 不同Conformality函数参数值计划的靶区剂量学差异均有统计学意义(P <0.05)。Conformality函数参数值为0.25时,靶区的Dmax、Dmin、Dmean与不加函数的增减幅度分别为2.45%、-0.96%、1.48%,适形度指数(CI)、均匀性指数(HI)增加0.05、0.04。当Conformality函数参数值> 0.50时,CI、HI基本无改变。小肠、结肠、左右股骨头的剂量学差异无统计学意义(P> 0.05)。当Conformality函数参数值为0.25时,直肠的V30、V40[(81.80±7.74)%、(63.44±10.23)%]、膀胱V30、V40[(78.82±5.69)%、(56.40±9.33)%]、正常组织V_(20)、V_(30)、V_(40)的体积[(6 137.64±622.88) cm^(3)、(2 903.55±221.08) cm^(3)、(1 862.93±112.81) cm^(3)]最低。Conformality函数在不同参数之下,膀胱、直肠V_(30)、V_(40)差异均具有统计学意义(P <0.05)。随着Conformality函数参数值增大机器参数值随之减小,机器跳数(MU)、控制点个数(CP)、执行时间(DT)在各Conformality函数参数值之间差异均有统计学意义(P <0.05)。结论 对于宫颈癌在Monaco计划系统中恰当使用Conformality函数设计计划可以提高计划质量,参数值设置在0.25~0.75为宜。综合剂量学参数及计划执行效率,推荐使用0.50。 展开更多
关键词 Monaco计划系统 宫颈癌 Conformality函数 剂量学
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高炉高球团比冶炼的煤气流流场与压力场数值模拟
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作者 奚旺 王振阳 张建良 《河北冶金》 2024年第10期20-27,共8页
在高炉生产冶炼中,提高球团矿比例会带来很多好处,如粒径均匀、SiO_(2)含量低于烧结矿、有利于间接还原、降低焦比和燃料比。然而,这也将导致软熔带透气性变差,高炉压差增大,同时抑制中心煤气流的发展,影响煤气流分布。本文利用数值模... 在高炉生产冶炼中,提高球团矿比例会带来很多好处,如粒径均匀、SiO_(2)含量低于烧结矿、有利于间接还原、降低焦比和燃料比。然而,这也将导致软熔带透气性变差,高炉压差增大,同时抑制中心煤气流的发展,影响煤气流分布。本文利用数值模拟方法研究了提高球团比例时,某36003高炉内煤气流流场与压力场的变化。研究结果表明,当球团比例从31%提高至60%时,高炉总压差增大9.45 kPa。其中,高球团比促进了块状带空隙度的增加,使上部和中部压差减小,而软熔带对煤气流的阻力增加,导致下部压差显著增大,且增幅超过中部和上部压差降幅之和。同时,气体流速整体受到抑制,料层煤气流流速降低0.16 m/s,中心煤气流速降低0.32 m/s,而软熔带焦窗区域煤气流速降幅更大,为0.63 m/s。此外,若提高球团矿比例的同时保持压差不变,需要将入炉风量降低268 m 3/min,高炉下部压力降低,但中心煤气流被进一步抑制;或优化原料条件,调整布料制度,将块状带空隙度从0.329增大至0.337,此时煤气流流速仍降低,但块状带料层煤气流分布得到改善。 展开更多
关键词 数值模拟 高球比 煤气流 压力场 速度场
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Bioengineered skin organoids:from development to applications
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作者 Zi-Xuan Hong Shun-Tian Zhu +5 位作者 Hao Li Jing-Zhi Luo Yu Yang Yang An xi wang Kai wang 《Military Medical Research》 SCIE CAS CSCD 2024年第3期449-466,共18页
Signifcant advancements have been made in recent years in the development of highly sophisticated skin organoids.Serving as three-dimensional(3D)models that mimic human skin,these organoids have evolved into complex s... Signifcant advancements have been made in recent years in the development of highly sophisticated skin organoids.Serving as three-dimensional(3D)models that mimic human skin,these organoids have evolved into complex structures and are increasingly recognized as efective alternatives to traditional culture models and human skin due to their ability to overcome the limitations of two-dimensional(2D)systems and ethical concerns.The inherent plasticity of skin organoids allows for their construction into physiological and pathological models,enabling the study of skin development and dynamic changes.This review provides an overview of the pivotal work in the progression from 3D layered epidermis to cyst-like skin organoids with appendages.Furthermore,it highlights the latest advancements in organoid construction facilitated by state-of-the-art engineering techniques,such as 3D printing and microfuidic devices.The review also summarizes and discusses the diverse applications of skin organoids in developmental biology,disease modelling,regenerative medicine,and personalized medicine,while considering their prospects and limitations. 展开更多
关键词 Skin organoid Organoid generation Skin appendage Tissue engineering Disease modelling Regenerative medicine
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Properties of radiation defects and threshold energy of displacement in zirconium hydride obtained by new deep-learning potential
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作者 王玺 唐孟 +3 位作者 蒋明璇 陈阳春 刘智骁 邓辉球 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期456-465,共10页
Zirconium hydride(ZrH_(2)) is an ideal neutron moderator material. However, radiation effect significantly changes its properties, which affect its behavior and the lifespan of the reactor. The threshold energy of dis... Zirconium hydride(ZrH_(2)) is an ideal neutron moderator material. However, radiation effect significantly changes its properties, which affect its behavior and the lifespan of the reactor. The threshold energy of displacement is an important quantity of the number of radiation defects produced, which helps us to predict the evolution of radiation defects in ZrH_(2).Molecular dynamics(MD) and ab initio molecular dynamics(AIMD) are two main methods of calculating the threshold energy of displacement. The MD simulations with empirical potentials often cannot accurately depict the transitional states that lattice atoms must surpass to reach an interstitial state. Additionally, the AIMD method is unable to perform largescale calculation, which poses a computational challenge beyond the simulation range of density functional theory. Machine learning potentials are renowned for their high accuracy and efficiency, making them an increasingly preferred choice for molecular dynamics simulations. In this work, we develop an accurate potential energy model for the ZrH_(2) system by using the deep-potential(DP) method. The DP model has a high degree of agreement with first-principles calculations for the typical defect energy and mechanical properties of the ZrH_(2) system, including the basic bulk properties, formation energy of point defects, as well as diffusion behavior of hydrogen and zirconium. By integrating the DP model with Ziegler–Biersack–Littmark(ZBL) potential, we can predict the threshold energy of displacement of zirconium and hydrogen in ε-ZrH_(2). 展开更多
关键词 zirconium hydride deep learning potential radiation defects molecular dynamics threshold energy of displacement
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Comparing gastrointestinal dysfunction score and acute gastrointestinal injury grade for predicting short-term mortality in critically ill patients
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作者 Chao Shen xi wang +3 位作者 Yi-Ying xiao Jia-Ying Zhang Guo-Lian xia Rong-Lin Jiang 《World Journal of Gastroenterology》 SCIE CAS 2024年第42期4523-4531,共9页
BACKGROUND The prognosis of critically ill patients is closely linked to their gastrointestinal(GI)function.The acute GI injury(AGI)grading system,established in 2012,is extensively utilized to evaluate GI dysfunction... BACKGROUND The prognosis of critically ill patients is closely linked to their gastrointestinal(GI)function.The acute GI injury(AGI)grading system,established in 2012,is extensively utilized to evaluate GI dysfunction and forecast outcomes in clinical settings.In 2021,the GI dysfunction score(GIDS)was developed,building on the AGI grading system,to enhance the accuracy of GI dysfunction severity assessment,improve prognostic predictions,reduce subjectivity,and increase reproducibility.AIM To compare the predictive capabilities of GIDS and the AGI grading system for 28-day mortality in critically ill patients.METHODS A retrospective study was conducted at the general intensive care unit(ICU)of a regional university hospital.All data were collected during the first week of ICU admission.The primary outcome was 28-day mortality.Multivariable logistic regression analyzed whether GIDS and AGI grade were independent risk factors for 28-day mortality.The predictive abilities of GIDS and AGI grade were compared using the receiver operating characteristic curve,with DeLong’s test assessing differences between the curves’areas.RESULTS The incidence of AGI in the first week of ICU admission was 92.13%.There were 85 deaths(47.75%)within 28 days of ICU admission.There was no initial 24-hour difference in GIDS between the non-survival and survival groups.Both GIDS(OR 2.01,95%CI:1.25-3.24;P=0.004)and AGI grade(OR 1.94,95%CI:1.12-3.38;P=0.019)were independent predictors of 28-day mortality.No significant difference was found between the predictive accuracy of GIDS and AGI grade for 28-day mortality during the first week of ICU admission(Z=-0.26,P=0.794).CONCLUSION GIDS within the first 24 hours was an unreliable predictor of 28-day mortality.The predictive accuracy for 28-day mortality from both systems during the first week was comparable. 展开更多
关键词 Critical illness Gastrointestinal dysfunction Acute gastrointestinal injury Prognostic indicators Intensive care unit outcomes Mortality prediction Risk stratification Predictive modeling
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Simulation of Fracture Process of Lightweight Aggregate Concrete Based on Digital Image Processing Technology
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作者 Safwan Al-sayed xi wang Yijiang Peng 《Computers, Materials & Continua》 SCIE EI 2024年第6期4169-4195,共27页
The mechanical properties and failure mechanism of lightweight aggregate concrete(LWAC)is a hot topic in the engineering field,and the relationship between its microstructure and macroscopic mechanical properties is a... The mechanical properties and failure mechanism of lightweight aggregate concrete(LWAC)is a hot topic in the engineering field,and the relationship between its microstructure and macroscopic mechanical properties is also a frontier research topic in the academic field.In this study,the image processing technology is used to establish a micro-structure model of lightweight aggregate concrete.Through the information extraction and processing of the section image of actual light aggregate concrete specimens,the mesostructural model of light aggregate concrete with real aggregate characteristics is established.The numerical simulation of uniaxial tensile test,uniaxial compression test and three-point bending test of lightweight aggregate concrete are carried out using a new finite element method-the base force element method respectively.Firstly,the image processing technology is used to produce beam specimens,uniaxial compression specimens and uniaxial tensile specimens of light aggregate concrete,which can better simulate the aggregate shape and random distribution of real light aggregate concrete.Secondly,the three-point bending test is numerically simulated.Thirdly,the uniaxial compression specimen generated by image processing technology is numerically simulated.Fourth,the uniaxial tensile specimen generated by image processing technology is numerically simulated.The mechanical behavior and damage mode of the specimen during loading were analyzed.The results of numerical simulation are compared and analyzed with those of relevant experiments.The feasibility and correctness of the micromodel established in this study for analyzing the micromechanics of lightweight aggregate concrete materials are verified.Image processing technology has a broad application prospect in the field of concrete mesoscopic damage analysis. 展开更多
关键词 Digital image processing lightweight aggregate concrete mesoscopic model numerical simulation fracture analysis bending beams
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Genetic mechanism of body size variation in groupers:Insights from phylotranscriptomics
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作者 Wei-Wei Zhang Zhuo-Ying Weng +5 位作者 xi wang Yang Yang Duo Li Le wang xiao-Chun Liu Zi-Ning Meng 《Zoological Research》 SCIE CSCD 2024年第2期314-328,共15页
Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within ... Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within the fish genus Epinephelus with evident divergence in body size,providing an excellent opportunity to investigate the genetic basis of body size variation in vertebrates.Herein,we performed phylotranscriptomic analysis and reconstructed the phylogeny of 13 epinephelids originating from the South China Sea.Two genetic clades with an estimated divergence time of approximately 15.4 million years ago were correlated with large and small body size,respectively.A total of 180 rapidly evolving genes and two positively selected genes were identified between the two groups.Functional enrichment analyses of these candidate genes revealed distinct enrichment categories between the two groups.These pathways and genes may play important roles in body size variation in groupers through complex regulatory networks.Based on our results,we speculate that the ancestors of the two divergent groups of groupers may have adapted to different environments through habitat selection,leading to genetic variations in metabolic patterns,organ development,and lifespan,resulting in body size divergence between the two locally adapted populations.These findings provide important insights into the genetic mechanisms underlying body size variation in groupers and species differentiation. 展开更多
关键词 Phylotranscriptomics GROUPER Body size Rapidly evolving genes(REGs) Positively selected genes(PSGs)
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Myotis bat STING attenuates aging-related inflammation in female mice
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作者 xi wang Jing-Kun Jia +4 位作者 Qi wang Jing-Wen Gong Ang Li Jia Su Peng Zhou 《Zoological Research》 SCIE CSCD 2024年第5期961-971,共11页
Bats,notable as the only flying mammals,serve as natural reservoir hosts for various highly pathogenic viruses in humans(e.g.,SARS-CoV and Ebola virus).Furthermore,bats exhibit an unparalleled longevity among mammals ... Bats,notable as the only flying mammals,serve as natural reservoir hosts for various highly pathogenic viruses in humans(e.g.,SARS-CoV and Ebola virus).Furthermore,bats exhibit an unparalleled longevity among mammals relative to their size,particularly the Myotis bats,which can live up to 40 years.However,the mechanisms underlying these distinctive traits remain incompletely understood.In our prior research,we demonstrated that bats exhibit dampened STING-interferon activation,potentially conferring upon them the capacity to mitigate virus-or aging-induced inflammation.To substantiate this hypothesis,we established the first in vivo bat-mouse model for aging studies by integrating Myotis davidii bat STING(MdSTING)into the mouse genome.We monitored the genotypes of these mice and performed a longitudinal comparative transcriptomic analysis on MdSTING and wild-type mice over a 3-year aging process.Blood transcriptomic analysis indicated a reduction in aging-related inflammation in female MdSTING mice,as evidenced by significantly lower levels of pro-inflammatory cytokines and chemokines,immunopathology,and neutrophil recruitment in aged female MdSTING mice compared to aged wild-type mice in vivo.These results indicated that MdSTING knock-in attenuates the aging-related inflammatory response and may also improve the healthspan in mice in a sex-dependent manner.Although the underlying mechanism awaits further study,this research has critical implications for bat longevity research,potentially contributing to our comprehension of healthy aging in humans. 展开更多
关键词 BAT STING Longevity Aging-related inflammation Virus reservoir host
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Assessing the performance of magnetopause models based on THEMIS data
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作者 Yang Lin JianYong Lu +1 位作者 BaoHang Qu xi wang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第5期776-786,共11页
The magnetopause is the boundary between the Earth’s magnetic field and the interplanetary magnetic field(IMF),located where the supersonic solar wind and magnetospheric pressure are in balance.Although empirical mod... The magnetopause is the boundary between the Earth’s magnetic field and the interplanetary magnetic field(IMF),located where the supersonic solar wind and magnetospheric pressure are in balance.Although empirical models and global magnetohydrodynamic simulations have been used to define the magnetopause,each of these has limitations.In this work,we use 15 years of magnetopause crossing data from the THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft and their corresponding solar wind parameters to investigate under which solar wind conditions these models predict more accurately.We analyze the pattern of large errors in the extensively used magnetopause model and show the specific solar wind parameters,such as components of the IMF,density,velocity,temperature,and others that produce these errors.It is shown that(1)the model error increases notably with increasing solar wind velocity,decreasing proton density,and increasing temperature;(2)when the cone angle becomes smaller or|Bx|is larger,the Shue98 model errors increase,which might be caused by the magnetic reconnection on the dayside magnetopause;(3)when|By|is large,the error of the model is large,which may be caused by the east-west asymmetry of the magnetopause due to magnetic reconnection;(4)when Bz is southward,the error of the model is larger;and(5)the error is larger for positive dipole tilt than for negative dipole tilt and increases with an increasing dipole tilt angle.However,the global simulation model by Liu ZQ et al.(2015)shows a substantial improvement in prediction accuracy when IMF Bx,By,or the dipole tilt cannot be ignored.This result can help us choose a more accurate model for forecasting the magnetopause under different solar wind conditions. 展开更多
关键词 MAGNETOPAUSE empirical model global magnetohydrodynamic simulation THEMIS solar wind parameters
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铁死亡在急性呼吸窘迫综合征中的基础研究和临床应用进展
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作者 王培 郁景文 +6 位作者 张立 奚望 薛小飞 张宇峰 肖健 杨潜 王志农 《海军军医大学学报》 CAS CSCD 北大核心 2024年第2期212-218,共7页
铁死亡是一种独特的调节性细胞死亡形式,特点是铁依赖的、脂质过氧化物的过量累积。铁死亡在形态学、生物学和遗传学等方面明显不同于凋亡、坏死、自噬及其他形式的细胞死亡。铁、脂肪、氨基酸代谢及其他信号通路与铁死亡密切相关。铁... 铁死亡是一种独特的调节性细胞死亡形式,特点是铁依赖的、脂质过氧化物的过量累积。铁死亡在形态学、生物学和遗传学等方面明显不同于凋亡、坏死、自噬及其他形式的细胞死亡。铁、脂肪、氨基酸代谢及其他信号通路与铁死亡密切相关。铁死亡与癌症、炎症、神经变性、肝肾损伤和缺血再灌注损伤等的病理过程密切相关。急性呼吸窘迫综合征(ARDS)是严重威胁人类生命健康的肺部炎症性疾病,发病率和死亡率高。近年来,人们对肺损伤发病机制和修复途径有了长足的认识,针对通气诱发肺损伤的疗法对ARDS患者是有益的,但仍缺乏有效的药物治疗方法。在全球范围内大流行的新型冠状病毒感染令ARDS的形势更加严峻,亟待进一步探索其在细胞、分子水平的机制并研发新的疗法。本文对铁死亡的定义、机制及其在ARDS中的基础研究和临床应用进展进行综述。 展开更多
关键词 铁死亡 急性呼吸窘迫综合征 肺损伤 代谢通路
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