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骨髓间充质干细胞治疗慢加急性肝衰竭小鼠实验研究
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作者 闻家兴 杨阳 +1 位作者 孟玉静 董林毅 《天津医科大学学报》 2025年第1期54-59,共6页
目的:研究骨髓间充质干细胞(hBMSCs)对慢加急性肝衰竭(ACLF)模型小鼠的治疗作用。方法:60只BALB/cJ小鼠随机分为正常组(n=8)和ACLF造模组(n=52),采用四氯化碳(CCl4)诱导法构建ACLF小鼠模型,ACLF造模组剔除死亡小鼠,随机分为模型组(n=11)... 目的:研究骨髓间充质干细胞(hBMSCs)对慢加急性肝衰竭(ACLF)模型小鼠的治疗作用。方法:60只BALB/cJ小鼠随机分为正常组(n=8)和ACLF造模组(n=52),采用四氯化碳(CCl4)诱导法构建ACLF小鼠模型,ACLF造模组剔除死亡小鼠,随机分为模型组(n=11)、hBMSCs低剂量治疗组(n=12)、中剂量治疗组(n=12)、高剂量治疗组(n=12)。采用生化分析仪检测小鼠血清谷氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆红素(TBIL)、总蛋白(TP)和白蛋白(ALB)水平;超敏多因子发光法(MSD)检测血清白细胞介素(IL)-Iβ、IL-6、IL-10、肿瘤坏死因子-α(TNF-α)、趋化因子配体1(KC/GRO)水平含量;苏木素-伊红(HE)和Masson染色,评价肝组织病理损伤程度。结果:与正常组相比,模型组AST、ALT、TBIL、TP、ALB水平显著升高(F=5.409、26.27、21.20、23.44、22.81,均P<0.001),AST/ALT比值显著降低(F=3.036,P<0.05)。与ACLF模型组比较,hBMSCs低、中剂量治疗组血清AST、ALT、TBIL水平显著降低(均P<0.05);中、高剂量治疗组AST/ALT比值显著升高(均P<0.05);hBMSCs低剂量治疗组血清IL-6、KC/GRO水平显著降低(均P<0.05);hBMSCs低、中剂量治疗组IL-1β、TNF-α水平降低(均P<0.05),而在hBMSCs低、中、高剂量治疗组中IL-10均升高(均P<0.05);低、中、高剂量治疗组TP、ALB、IFN-γ、IL-2、IL-5差异没有统计学意义(均P>0.05);hBMSCs低、中剂量治疗组肝组织炎细胞浸润及坏死区域均显著减少(均P<0.05),肝组织胶原纤维阳性面积显著降低(均P<0.05)。结论:hBMSCs对CCl4诱导的ACLF小鼠模型具有显著的治疗作用,治疗效果未见剂量依赖,其中低剂量组治疗效果更佳。 展开更多
关键词 人骨髓间充质干细胞 慢加急性肝衰竭 炎性因子 肝纤维化
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Full Ceramic Bearing Fault Diagnosis with Few-Shot Learning Using GPT-2
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作者 David He Miao He Jay Yoon 《Computer Modeling in Engineering & Sciences》 2025年第5期1955-1969,共15页
Full ceramic bearings are mission-critical components in oil-free environments,such as food processing,semiconductor manufacturing,and medical applications.Developing effective fault diagnosis methods for these bearin... Full ceramic bearings are mission-critical components in oil-free environments,such as food processing,semiconductor manufacturing,and medical applications.Developing effective fault diagnosis methods for these bearings is essential to ensuring operational reliability and preventing costly failures.Traditional supervised deep learning approaches have demonstrated promise in fault detection,but their dependence on large labeled datasets poses significant challenges in industrial settings where fault-labeled data is scarce.This paper introduces a few-shot learning approach for full ceramic bearing fault diagnosis by leveraging the pre-trained GPT-2 model.Large language models(LLMs)like GPT-2,pre-trained on diverse textual data,exhibit remarkable transfer learning and few-shot learning capabilities,making them ideal for applications with limited labeled data.In this study,acoustic emission(AE)signals from bearings were processed using empirical mode decomposition(EMD),and the extracted AE features were converted into structured text for fine-tuning GPT-2 as a fault classifier.To enhance its performance,we incorporated a modified loss function and softmax activation with cosine similarity,ensuring better generalization in fault identification.Experimental evaluations on a laboratory-collected full ceramic bearing dataset demonstrated that the proposed approach achieved high diagnostic accuracy with as few as five labeled samples,outperforming conventional methods such as k-nearest neighbor(KNN),large memory storage and retrieval(LAMSTAR)neural network,deep neural network(DNN),recurrent neural network(RNN),long short-term memory(LSTM)network,and model-agnostic meta-learning(MAML).The results highlight LLMs’potential to revolutionize fault diagnosis,enabling faster deployment,reduced reliance on extensive labeled datasets,and improved adaptability in industrial monitoring systems. 展开更多
关键词 LLMs GPT-2 few-shot learning fault diagnosis full ceramic bearing acoustic emission
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One new sap beetle species of Pocadius Erichson(Coleoptera:Nitidulidae:Nitidulinae)
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作者 Huan ZHANG Xiaoxiao CHEN +1 位作者 Josef JELÍNEK Min HUANG 《Entomotaxonomia》 2025年第1期26-29,共4页
One new species,Pocadius spiralis sp.nov.,is described and illustrated from Sichuan,China.
关键词 POLYPHAGA Nitiduloidea morphology TAXONOMY
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基于距离误差的机器人参数辨识模型与冗余性分析 被引量:7
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作者 申景金 郭家桢 MASOUD Kalantari 《农业机械学报》 EI CAS CSCD 北大核心 2018年第11期372-378,共7页
为避免机器人运动学参数辨识过程中,测量坐标系与机器人基坐标系之间繁琐的坐标变换,首先利用关节旋量的空间几何特性,提出了基于伴随变换的距离误差模型。其次,针对距离误差模型中可辨识参数的冗余性,通过辨识雅可比矩阵的零空间分析,... 为避免机器人运动学参数辨识过程中,测量坐标系与机器人基坐标系之间繁琐的坐标变换,首先利用关节旋量的空间几何特性,提出了基于伴随变换的距离误差模型。其次,针对距离误差模型中可辨识参数的冗余性,通过辨识雅可比矩阵的零空间分析,确定了可辨识参数的数目与误差测量方式之间的关系。确定了绕对应关节旋转的测量方式和相对初始位形的测量方式下可辨识参数的数目。最后,对KUKA you Bot机器人的运动学参数辨识进行了实验研究,实验结果验证了距离误差模型的有效性和参数冗余性分析的正确性。 展开更多
关键词 机器人 运动学辨识 距离误差 伴随变换 冗余参数
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混凝土结构中钢筋初始表面状态对其腐蚀行为的影响 被引量:1
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作者 曹忠露 米胜东 +2 位作者 陈浩宇 魏连雨 日比野誠 《四川建筑科学研究》 北大核心 2017年第1期50-54,共5页
建立了宏电池腐蚀回路,通过分析不同初始表面状态的钢筋在无氯盐试块和有氯盐试块中的腐蚀电位、微电池腐蚀速度、极化曲线和宏电池腐蚀速度,研究了钢筋初始表面状态对其腐蚀行为的影响。结果表明,与全裸抛光表面相比,原氧化皮表面或初... 建立了宏电池腐蚀回路,通过分析不同初始表面状态的钢筋在无氯盐试块和有氯盐试块中的腐蚀电位、微电池腐蚀速度、极化曲线和宏电池腐蚀速度,研究了钢筋初始表面状态对其腐蚀行为的影响。结果表明,与全裸抛光表面相比,原氧化皮表面或初始锈蚀表面对改善钢筋的腐蚀电位起积极作用。锈蚀表面钢筋的微电池腐蚀速度较大且随着初始锈蚀程度的增加而增大。与初始锈蚀表面相比,原氧化皮表面能削弱钢筋的微电池腐蚀,但对其宏电池腐蚀有不利的影响。 展开更多
关键词 混凝土 钢筋 初始表面状态 微电池腐蚀 宏电池腐蚀
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赤松一新变种 被引量:20
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作者 张树杰 黎承湘 袁晓颖 《植物研究》 CAS CSCD 北大核心 1995年第3期338-341,共4页
本文发表了赤松一新变种即彰武松PinusdensifloraSieb.etZucc.var.zhangwuensisZhang,LietYuanvar.nov.
关键词 赤松 彰武松 新变种
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导致钻铤失效的井下振动分析及其解决方案 被引量:9
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作者 朱全塔 邹宗明 +2 位作者 黄兵 马林虎 夏家祥 《天然气工业》 EI CAS CSCD 北大核心 2016年第12期80-86,共7页
在某些区块或地层尤其是大井眼钻进时,因井下存在较为严重的振动,钻铤出现频繁的疲劳破坏,且多数刺漏、断裂处于螺纹根部。分析上述钻铤失效的原因后发现:井下严重的振动所引起的循环往复弯曲应力导致了该种疲劳破坏。为此,对井下振动... 在某些区块或地层尤其是大井眼钻进时,因井下存在较为严重的振动,钻铤出现频繁的疲劳破坏,且多数刺漏、断裂处于螺纹根部。分析上述钻铤失效的原因后发现:井下严重的振动所引起的循环往复弯曲应力导致了该种疲劳破坏。为此,对井下振动模式进行理论分析,包括纵向振动、横向振动和粘滑(扭转)振动及力学界建立的物理模型,从理论角度剖析了实际井下不同振动形式可能产生共振的危害和理论依据;然后根据钻柱井下横向振动情况及涡动规律,分析了根据既定的边界条件确保稳定的钻井参数的最佳区域,阐释了在最佳区域内钻井,既可以保持钻具的稳定或消除涡动和粘滑振动以获得最大机械钻速,还可以减少或消除下部钻具尤其是钻铤的交变应力疲劳的认识。最后提出了减弱和消除井下振动的解决方案:(1)根据特定的钻具组合、钻井环境,运用上述建立的物理和数学模型,可以较为方便地计算出应该避免的可能引起井下共振的转速及相关参数,且共振转速恰恰就是最佳防振转速,利用井下振动分析软件在钻具组合设计和现场施工时可以避开共振频率;(2)V形扶正器是一种新颖且高效的减弱和消除井下横向和粘滑振动的工具。 展开更多
关键词 纵向振动 横向振动 扭转(粘滑)振动 共振 钻铤疲劳失效 振动 分析软件 V形扶正器
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在批次和固定床反应器中用于菜子油酯化K/Al_2O_3催化剂的稳定性(英文) 被引量:2
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作者 Petr Kutálek Libor apek +2 位作者 Lucie Smoláková David Kubikb Martin Hájek 《催化学报》 SCIE CAS CSCD 北大核心 2014年第7期1084-1090,共7页
关键词 固定床反应器 固体催化剂 AL2O3 稳定性 菜籽油 转移反应 傅立叶变换红外光谱法 酯基
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HPLC双波长切换法测定二妙丸中盐酸小檗碱、苍术素含量 被引量:4
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作者 郭晓 张伟 +4 位作者 贾晓益 孙孟情 贾鹏晖 王志新 钱都 《贵阳中医学院学报》 2017年第5期31-34,90,共5页
目的:建立HPLC双波长切换法对二妙丸中盐酸小檗碱、苍术素的含量测定,该方法有利于二妙丸的含量测定及质量控制。方法:采用反相高效液相色谱法;以0.02mol/L磷酸二氢钾(用磷酸调PH3.0)-乙腈(色谱纯)流动相梯度洗脱;流速:1.0m L/min;柱温... 目的:建立HPLC双波长切换法对二妙丸中盐酸小檗碱、苍术素的含量测定,该方法有利于二妙丸的含量测定及质量控制。方法:采用反相高效液相色谱法;以0.02mol/L磷酸二氢钾(用磷酸调PH3.0)-乙腈(色谱纯)流动相梯度洗脱;流速:1.0m L/min;柱温:30℃;检测波长:270nm(0~10min,盐酸小檗碱)、340nm(10~20min,苍术素);结果:HPLC双波长切换法可同时测定二妙丸中盐酸小檗碱、苍术素的含量,盐酸小檗碱和苍术素分别在14.63~292.5μg/m L、0.54~10.75μg/m L和峰面积呈良好的线性关系,平均加样回收率(N=6)分别为99.8196%、99.2808%。RSD分别为0.6163%、2.1763%。结论:该方法准确、可靠、专属性强,为二妙丸的质量控制提供参考。 展开更多
关键词 双波长切换 二妙丸 盐酸小檗碱 苍术素 HPLC—DAD
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Tracking Regulatory Mechanism of Trace Fe on Graphene Electromagnetic Wave Absorption 被引量:4
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作者 Kaili Zhang Yuhao Liu +5 位作者 Yanan Liu Yuefeng Yan Guansheng Ma Bo Zhong Renchao Che Xiaoxiao Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期79-96,共18页
Polarization and conductance losses are the fundamental dielectric attenuation mechanisms for graphene-based absorbers, but it is not fully understood in revealing the loss mechanism of affect graphene itself. For the... Polarization and conductance losses are the fundamental dielectric attenuation mechanisms for graphene-based absorbers, but it is not fully understood in revealing the loss mechanism of affect graphene itself. For the first time, the reduced graphene oxide(RGO) based absorbers are developed with regulatory absorption properties and the absorption mechanism of RGO is mainly originated from the carrier injection behavior of trace metal Fe nanosheets on graphene. Accordingly, the minimum reflection loss(RLmin) of Fe/RGO-2composite reaches-53.38 dB(2.45 mm), and the effective absorption bandwidth achieves 7.52 GHz(2.62 mm) with lower filling loading of 2 wt%. Using off-axis electron hologram testing combined with simulation calculation and carrier transport property experiments, we demonstrate here the carrier injection behavior from Fe to graphene at the interface and the induced charge accumulation and rearrangement, resulting in the increased interfacial and dipole polarization and the conductance loss. This work has confirmed that regulating the dielectric property of graphene itself by adding trace metals can not only ensure good impedance matching, but also fully exploit the dielectric loss ability of graphene at low filler content,which opens up an efficient way for designing lightweight absorbers and may be extended to other types materials. 展开更多
关键词 Reduced graphene oxide Fe nanosheets Dielectric loss Electromagnetic wave absorption
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残余应力导致三层聚烯烃管道防腐层剥离与开裂 被引量:3
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作者 B.T.A.Cheng S Hung-jue +7 位作者 J Han D Wong A Kehr M Mallozzi F Aguirre H Pham W Snider 王向农(译) 《防腐保温技术》 2011年第3期44-55,共12页
这是美国运输部发起的研究项目,一个管道防腐层专家团队参与了本研究项目,评价了三层聚烯烃管道外防腐涂层(3LPO)的完整性。研究表明,三层聚烯烃管道外防腐涂层(3LPO)存在剥离和面层开裂两大完整性问题。过去几年里,据文献报道... 这是美国运输部发起的研究项目,一个管道防腐层专家团队参与了本研究项目,评价了三层聚烯烃管道外防腐涂层(3LPO)的完整性。研究表明,三层聚烯烃管道外防腐涂层(3LPO)存在剥离和面层开裂两大完整性问题。过去几年里,据文献报道,三层聚烯烃管道外防腐涂层(3LPO)的熔结环氧粉末(FBE)底漆与钢管界面上发生多起防腐层剥离事故,以及聚丙烯(PP)面层发生开裂事故。这些防腐层事故引起人们对使用三层聚烯烃管道外防腐涂层(3LPO)的关注。一般来讲,三层聚烯烃管道外防腐涂层(3LPO)采用比较厚的聚烯烃面层增强防腐层抗机械损伤和防止水渗透的能力。但是,聚烯烃的热膨胀系数比钢材高得多,结果在防腐层系统里产生比较高的残余热应力。因为残余应力高,造成防腐层剥离,尤其在管端截短防腐层和任何防腐层的边上,因为这些是高应力集中部位。特别是假如钢管表面预处理不当,就无法保证防腐层持久达到很强的粘合强度。如果熔结环氧粉末(FBE)底漆配方选择不当,发生热氧化降解,也导致防腐层过早失效。如果使用温度很高,聚丙烯也会因为热氧化降解而变脆。在残余应力下,这样脆性的聚丙烯面层就会开裂。本文分析了三层聚烯烃管道外防腐涂层(3LPO)中的残余应力,并且探讨了残余应力对三层聚烯烃管道外防腐涂层(3LPO)剥离和聚丙烯(PP)面层开裂机理的影响。 展开更多
关键词 残余应力 热氧化降解 防腐层剥离 聚丙烯开裂
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Makeup Activates Brain Activity in Visually Impaired Persons: Evaluation by Functional Magnetic Resonance Imaging
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作者 Katsushi Taomoto Kaho Oishi +5 位作者 Hiroshi Matsunaka Yumi Murakami Yoshihiro Kuga Shinsuke Hashimoto Hideyuki Ohnishi Koji Abe 《Journal of Cosmetics, Dermatological Sciences and Applications》 2021年第2期140-154,共15页
Cosmetics are used to improve physical appearance, but the benefits may be limited to people without visual impairment. The importance of attractiveness among blind persons has not been assessed. We investigated the i... Cosmetics are used to improve physical appearance, but the benefits may be limited to people without visual impairment. The importance of attractiveness among blind persons has not been assessed. We investigated the influence of makeup on brain activity of blind persons using functional magnetic resonance imaging (fMRI). Participants were 7 blind females (BFs) who learned to fully apply makeup and 9 mostly age-matched normally sighted females (NSFs). Brain activity was measured using fMRI before and after application of makeup and during a makeup image task in each state. In the default mode network at rest, there was no difference between the BFs and NSFs. However, a lateral visual network to the opposite side was observed in the NSFs, whereas no such network was noted in the BFs. A weak network was noted in the BFs in the occipital fusiform gyrus and temporal occipital fusiform cortex, and an extensive visual area network defect was noted. Also, activity after makeup application was significantly higher in the nucleus accumbens, pallidum, and hippocampus. Activity in the right middle cingulate gyrus, right cerebral white matter, and right anterior cingulate gyrus was higher before makeup in both BFs and NSFs, and the activity was significantly higher and more extensive in the BFs. In conclusion, applying makeup is a personally rewarding activity, even for BFs, as it strongly activates the reward system and the reward/memory system network, even in the absence of a visual area network. 展开更多
关键词 Functional Magnetic Resonance Imaging Visually Impaired Persons Brain Activity MAKEUP FEMALE
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Characterization of Okra Convective Drying, Influence of Maturity 被引量:1
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作者 Ouoba Kondia Honoré Zougmoré François +2 位作者 Sam Raguilignaba Toguyeni Aboubacar Desmorieux Hélène 《Food and Nutrition Sciences》 2014年第6期590-597,共8页
An experimental study for the drying kinetics of whole okra was carried out. In the study, different ages were considered by taking into account influence of okra maturity on its convective drying. The 2D moisture evo... An experimental study for the drying kinetics of whole okra was carried out. In the study, different ages were considered by taking into account influence of okra maturity on its convective drying. The 2D moisture evolution inside the product and its maturity were evaluated by fitting experimental data versus drying time. The water effective diffusion coefficient of okra at different maturity states was gotten by the experimental model using Fick’s second law. A parametric study was carried out in the ranging of okra age from 2 to 7 days at 60℃, both fruits gathered on the same plant to avoid divergences due to okra varieties that can induce difference on physical structure and the chemical composition. It was found from the experimental results that okra maturity has important influence on its behaviour during convective drying. At 2, 3, 4, 5 and 7 days old, the drying effective time was respectively 780, 1000, 1155, 850 and 750 min. Effective diffusivity of the okra in this order of age was 1.38 × 10-10, 6.09 × 10-11, 1.23 × 10-11, 8.98 × 10-11, and 1.05 × 10-10 m2/s in the present study, while the average initial moisture content was respectively 12.27, 9.00, 7.53, 5.97 and 4.92 Kgw/Kgdm. 展开更多
关键词 Convective Drying OKRA Effective Diffusivity MATURITY Initial Moisture Content
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Effective Skin Care Guidance for Patients with Acne Vulgaris after Standard Treatment
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作者 Katsuko Kikuchi Yumi Murakami +5 位作者 Haruna Sato Ryoko Yamashita Yumiko Saya Ichiko Morino Rikako Uchino Hiroshi Matsunaka 《Journal of Cosmetics, Dermatological Sciences and Applications》 2023年第4期345-356,共12页
With the introduction of new drugs, the treatment of acne vulgaris has improved dramatically;however, there remains a considerable gap between treatment outcomes and patients’ treatment goals. This study aimed to det... With the introduction of new drugs, the treatment of acne vulgaris has improved dramatically;however, there remains a considerable gap between treatment outcomes and patients’ treatment goals. This study aimed to determine whether dermatologists’ guidance on appropriate skincare for skin symptoms such as post-inflammatory erythema and post-inflammatory hyperpigmentation (PIH), which are not covered by acne treatment, leads to an improvement in patients’ skin condition and patient satisfaction. Japanese women who had completed standard treatment for acne vulgaris and those with mild symptoms not requiring treatment were included in the study. The participants received instructions about skin care at the beginning of the study, which they continued to apply for 6 weeks. At the start and end of the study, participants were examined by a dermatologist;afterward, skin measurements, including skin color, skin surface lipid content, and image analysis by VISIA<sup>®</sup> Evolution, analysis of stratum corneum obtained from the skin surface, and Skindex-16 questionnaire for assessing quality of life (QOL), were performed. The following showed significant improvements: PIH score, number of inflammatory acne lesions, and number of non-inflammatory acne lesions observed via skin examination;skin surface lipid content and values of L* and a* obtained via instrumental measurement;n number of pore, texture, red spot, and pigmented spot obtained via by image analysis;and degree of multilayer exfoliation and interleukin-1α determined by analysis of epidermal stratum corneum. QOL measurement using Skindex-16 also improved significantly. Appropriate skin care guidance following standard acne vulgaris treatment is helpful in achieving patients’ treatment goals. . 展开更多
关键词 Acne Vulgaris Skin Care Post-Inflammatory Hyperpigmentation Post-Inflammatory Erythema Quality of Life
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UHPFRC Cast-in-Situ Over-Lay of Bridge Abutments
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作者 RomanŠafář Miloslav Kovač Robert Coufal 《Journal of Civil Engineering and Architecture》 2023年第10期479-483,共5页
Use of UHPFRC(ultra high performance fiber reinforced concrete)cast-in-situ over-lays for repairs and strengthening of bridge decks is already quite a widely used technology,while use of this method for strengthening ... Use of UHPFRC(ultra high performance fiber reinforced concrete)cast-in-situ over-lays for repairs and strengthening of bridge decks is already quite a widely used technology,while use of this method for strengthening of bridge supports is still much less often.This paper describes the first use of this technology for bridge abutments in the Czech Republic,and if we know well,also the first use of such a ribbed over-lay internationally. 展开更多
关键词 Strengthening of bridges bridge abutments bridge supports UHPFRC over-lay
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Silver fir tree-ring fluctuations decrease from north to south latitude—total solar irradiance and NAO are indicated as the main influencing factors
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作者 Vaclav Simůnek Anna Prokůpkova +10 位作者 Zdenek Vacek Stanislav Vacek Jan Cukor Jirí Remes Vojtech Hajek Giuseppe D'Andrea Martin Salek Paola Nola Osvaldo Pericolo Sarka Holzbachova Francesco Ripullone 《Forest Ecosystems》 SCIE CSCD 2023年第6期717-731,共15页
Silver fir(Abies alba Mill.)is a flexible European tree species,mainly vegetating within the mountainous regions of Europe,but its growth responses across its latitudinal and longitudinal range have not yet been satis... Silver fir(Abies alba Mill.)is a flexible European tree species,mainly vegetating within the mountainous regions of Europe,but its growth responses across its latitudinal and longitudinal range have not yet been satisfactorily verified under changing environmental conditions.This study describes the tree-ring increment of silver fir in research plots across a latitudinal gradient from the northern range in Czechia(CZ),through Croatia(HR)to the southernmost range in Italy(IT).The research aims to analyze in detail the dynamics and cyclicity of the ringwidth index(RWI)and how it relates to climatic factors(temperature and precipitation),the North Atlantic Oscillation(NAO),and total solar irradiance(TSI),including the determination of latitude.The results show that the main drivers affecting fir growth are the seasonal NAO index and TSI.Monthly temperatures affect RWI early in the vegetation season,while lack of precipitation during the summer is a limiting factor for fir growth,especially in July.Seasonal temperatures and temperatures in June and July negatively impact,while seasonal precipitation totals in the same months positively influence the RWI in all research plots across meridian.The longest growth cycles in fir RWI were recorded in the northernmost studied plots in CZ.These cyclical fluctuations recede approaching the south.The cyclic increase in RWI is related to the TSI,which decreases its effect from north to south.The TSI's effects vary,positively impacting CZ but negatively influencing HR while remaining relatively neutral in IT.On the other hand,seasonal NAO tends to negatively affect silver fir growth in HR and CZ but has a mildly positive effect in IT.In conclusion,the TSI and the influence of the seasonal NAO index are prevalent in the fir RWI and are accompanied by a greater cyclicity of RWI in Central Europe(temperature optimum)than in the Italian Mediterranean region,where this tree species is limited by climatic conditions,especially lack of precipitation. 展开更多
关键词 Abies alba Mill TREE-RINGS Solar cycle North Atlantic oscillation Precipitation Temperature
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Downhole vibration causing a drill collar failure and solutions
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作者 Zhu Quanta Zou Zongming +2 位作者 Huang Bing Ma Linhu Xia Jiaxiang 《Natural Gas Industry B》 2017年第2期73-80,共8页
In large borehole drilling of some blocks or formations,due to serious downhole vibration,fatigue failure of a drill collar occurs frequently and most washouts and fractures are in thread root.An analysis of the above... In large borehole drilling of some blocks or formations,due to serious downhole vibration,fatigue failure of a drill collar occurs frequently and most washouts and fractures are in thread root.An analysis of the above failure shows that the drill collar fatigue failure is caused by the cyclic bending stress due to serious downhole vibration.Therefore,downhole vibration modes were theoretically analyzed in terms of axial vibration,lateral vibration,stick-slip,and the physical model established by the mechanical vibration field.Then the resonance damage caused by the actual different downhole vibrations and its theoretical basis were analyzed;and according to the downhole drill string lateral vibration and whirling law,the best area to ensure drilling parameter stability based on the given boundary conditions was figured out,and the theory was clarified that in the best area of drilling,the maximum ROP will be achieved by maintaining the drill string stable or eliminating the vibration/stick-slip,meanwhile the stress fatigue of BHA will be reduced or eliminated especially for drill collar.Finally,solutions were provided as follows:(1)According to the special BHA,drilling conditions,together with physical and mathematical models listed above,downhole resonance speed and related parameters to be avoided can be easily figured out.It was also clarified that resonance speed is exactly the vibration speed that need to be avoided;and that the resonance frequency can be avoided with software for vibration analysis in BHA design and application at well sites;(2)V-Stab is a new and efficient tool which can reduce or eliminate downhole lateral vibration and stick-slip. 展开更多
关键词 Axial vibration Lateral vibration STICK-SLIP RESONANCE Drill collar Fatigue failure Software for vibration analysis V-Stab
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Incidence of urinary incontinence following endoscopic laser enucleation of the prostate by en-bloc and non-en-bloc techniques:a multicenter,real-world experience of 5068 patients 被引量:3
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作者 Daniele Castellani Vineet Gauhar +19 位作者 Khi Yung Fong Mario Sofer Moisés Rodríguez Socarrás Azimdjon N Tursunkulov Lie Kwok Ying Sarvajit Biligere Ho Yee Tiong Dean Elterman Abhay Mahajan Mark Taratkin Sorokin Nikolai Ivanovich Tanuj Pal Bhatia Dmitry Enikeev Nariman Gadzhiev Mohammed Taif Bendigeri Jeremy Yuen-Chun Teoh Marco Dellabella Fernando Gómez Sancha Bhaskar Kumar Somani Thomas Reinhard William Herrmann 《Asian Journal of Andrology》 SCIE CAS CSCD 2024年第3期233-238,共6页
We aim to evaluate the incidence of incontinence following laser endoscopic enucleation of the prostate(EEP)comparing en-bloc(Group 1)versus 2-lobe/3-lobe techniques(Group 2).We performed a retrospective review of pat... We aim to evaluate the incidence of incontinence following laser endoscopic enucleation of the prostate(EEP)comparing en-bloc(Group 1)versus 2-lobe/3-lobe techniques(Group 2).We performed a retrospective review of patients undergoing EEP for benign prostaticenlargement in 12 centers between January 2020 and January 2022.Data were presented as median and interquartile range(IQR).Univariable and multivariable logistic regression analysis was performed to evaluate factors associated with stress urinary incontinence(SUI)and mixed urinary incontinence(MUI).There were 1711 patients in Group 1 and 3357 patients in Group 2.Patients in Group 2were significantly younger(68[62–73]years vs 69[63–74]years,P=0.002).Median(interquartile range)prostate volume(PV)wassimilar between the groups(70[52–92]ml in Group 1 vs 70[54–90]ml in Group 2,P=0.774).There was no difference in preoperativeInternational Prostate Symptom Score,quality of life,or maximum flow rate.Enucleation,morcellation,and total surgical time weresignificantly shorter in Group 1.Within 1 month,overall incontinence rate was 6.3%in Group 1 versus 5.3%in Group 2(P=0.12),and urge incontinence was significantly higher in Group 1(55.1%vs 37.3%in Group 2,P<0.001).After 3 months,the overall rate ofincontinence was 1.7%in Group 1 versus 2.3%in Group 2(P=0.06),and SUI was significantly higher in Group 2(55.6%vs 24.1%in Group 1,P=0.002).At multivariable analysis,PV and IPSS were factors significantly associated with higher odds of transient SUI/MUI.PV,surgical time,and no early apical release technique were factors associated with higher odds of persistent SUI/MUI. 展开更多
关键词 benign prostatic hyperplasia en-bloc enucleation endoscopic enucleation of the prostate laser therapy stress urinaryincontinence urge urinary incontinence
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Woody plant taxonomic,functional,and phylogenetic diversity decrease along elevational gradients in Andean tropical montane forests:Environmental filtering and arrival of temperate taxa
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作者 Guillermo Bañares-de-Dios Manuel J.Macía +6 位作者 Gabriel Arellano Íñigo Granzow-de la Cerda Julia Vega-álvarez Itziar Arnelas Carlos I.Espinosa Norma Salinas Luis Cayuela 《Plant Diversity》 SCIE CAS CSCD 2024年第4期491-501,共11页
Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short distances.Biodiversity research has traditionally focused on taxonomic diversity when i... Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short distances.Biodiversity research has traditionally focused on taxonomic diversity when investigating changes along elevational gradients,but other facets should be considered.For first time,we simultaneously assessed elevational trends in taxonomic,functional,and phylogenetic diversity of woody plants in Andean tropical montane forests and explored their underlying ecological and evolutionary causes.This investigation covered four transects(traversing ca.2200 m a.s.l.) encompassing 114 plots of 0.1 ha across a broad latitudinal range(ca.10°).Using Hill numbers to quantify abundance-based diversity among 37,869 individuals we observed a consistent decrease in taxonomic,functional,and phylogenetic diversity as elevation increased,although the decrease was less pronounced for higher Hill orders.The exception was a slight increase in phylogenetic diversity when dominant species were over-weighted.The decrease in taxonomic and functional diversity might be attributed to an environmental filtering process towards highlands,where the increasingly harsher conditions exclude species and functional strategies.Besides,the differences in steepness decrease between Hill orders suggest that rare species disproportionately contribute to functional diversity.For phylogenetic diversity the shifting elevational trend between Hill orders indicates a greater than previously considered influence in central Andean highlands of tropical lowlands originated species with strong niche conservatism relative to distantly related temperate lineages.This could be explained by a decreasing presence and abundance of temperate,extratropical taxa towards the central Andes relative to northern or southern Andes,where they are more prevalent. 展开更多
关键词 Altitudinal gradients ANDES Environmentalfiltering Out of the Tropical Lowlands Functional rarity Tropical Niche Conservatism
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Expert consensus on the technical specifications of the in vitro skin penetration test of cosmetic product by Franz diffusion cell
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作者 Bingwen Liang Liling Zhou +29 位作者 Chuanbin Wu Liang Fang Lisheng Wang Lihua Peng Peng Shu Lifeng Tang Yu Bei Xiaodong Cui Xiaojia Chen Yuan Gao Chong Han Yan Jia Huaqing Lim Yifang Li Ying Liu Yiguang Li Zhiwei Li Zixiu Liu Shaohua Ren Jun Shi Wanyang Sun Lijuan Tian Qun Wang Yuan Wang Yuehong Xu Ming Zeng Quangang Zhu Shu Zhang Yifan Zhang Qi Xiang 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第3期79-85,共7页
Background:Diffusion cell test is one of the most commonly used in vitro model to detect the percutaneous absorption of cosmetic ingredients.Although PRC State Administration of Quality Supervision and Quarantine has ... Background:Diffusion cell test is one of the most commonly used in vitro model to detect the percutaneous absorption of cosmetic ingredients.Although PRC State Administration of Quality Supervision and Quarantine has issued the guideline for the in vitro test method for the percutaneous absorption of drug molecules,there is still a lack of guideline for the percutaneous absorption test of cosmetic components.Objective:In order to improve the standardized level and make the in vitro percutaneous absorption test of cosmetic ingredients more comparable,based on the international and domestic experience,Transdermal Drug Delivery Committee of the World Federation of Chinese Medicine Societies organized the experts to discuss and formed this consensus as reference for the percutaneous absorption test of cosmetic components.Materials and Methods:To standardize the in vitro diffusion cell test technique for transdermal penetration of functional cosmetic ingredients,the Transdermal Drug Delivery Professional Committee of the World Federation of Societies of Traditional Chinese Medicine has organized many discussions among experts. 展开更多
关键词 COSMETICS Percutaneous absorption Diffusion cell Expert consensus
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