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Thickening progression mechanism of silica fume-oil well cement composite system at high temperatures

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Petroleum Science 2024年第4期21卷 2793-2805页

作者： Hang Zhang Miao-Miao Hu Peng-Peng Li Guo-Qing Liu Qing-Lu Chang Jie Cao Ming Liu Wen-hua Xu xiu-Jian Xia Jin-Tang Guo School of Chemical Engineering and Technology Tianjin University Zhejiang Institute of Tianjin University Haihe Laboratory of Sustainable Chemical Transformations CNPC Engineering Technology R&D Company Limited

This work studied the thickening progression mechanism of the silica fume-oil well cement composite system at high temperatures(110-180.C) in order to provide a theoretical guidance for the rational application of silica fume in the cementing engineering. Results showed that silica fume seldom affected the thickening progression of oil well cement slurry at 110-120.C, but when temperature reached above130.C, it would aggravate the bulging degree of thickening curves and significantly extend the thickening time, meanwhile causing the abnormal “temperature-based thickening time reversal” and“dosage-based thickening time reversal” phenomena in the range of 130-160.C and 170-180.C respectively. At 130-160.C, the thickening time of oil well cement slurry was mainly associated with the generation rate of calcium hydroxide(CH) crystal. The introduced silica fume would be attracted to the cement minerals' surface that were hydrating to produce CH and agglomerate together to form an“adsorptive barrier” to hinder further hydration of the inner cement minerals. This “adsorptive barrier”effect strengthened with the rising temperature which extended the thickening time and caused the occurrence of the “temperature-based thickening time reversal” phenomenon. At 170-180.C, the pozzolanic activity of silica fume significantly enhanced and considerable amount of C-S-H was generated, thus the “temperature-based thickening time reversal” vanished and the “dosage-based thickening time reversal” was presented.

关键词： Silica fume Oil well cement Thickening time reversal Pozzolanic reaction Adsorptive barrier CH and C−S−H

Defects in phospholipase C zeta cause polyspermy and low fertilization after conventional IVF:not just ICSI failure

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Asian Journal of Andrology 2024年第2期26卷 175-182页

作者： Jian-Fang Che Hui-Xia Wu Si-Cong Zeng Yue-Ren Wu Jing Dai De-hua Cheng Fei Gong Guang-xiu Lu Ge Lin Can Dai School of Medicine Hunan Normal UniversityChangsha 410013China Reproductive and Genetic Hospital of CITIC-Xiangya Changsha 410008China Clinical Research Center for Reproduction and Genetics in Hunan Province Changsha 410078China National Engineering and Research Center of Human Stem Cell Changsha 410205China

Phospholipase C zeta(PLC)is a key sperm-borne oocyte-activating factor that triggers Ca^(2+)oscillations and the subsequent block to polyspermy following gamete *** in PLCZ1,the gene encoding PLCζ,cause male infertility and intracytoplasmic sperm injection(ICSI)fertilization failure;and PLCζ expression and localization patterns are significantly correlated with ICSI fertilization rate(FR).However,in conventional in vitro fertilization(cIVF),whether and how sperm PLCζ affects fertilization remain ***,we identified one previously reported and two novel PLCZ1 mutations associated with polyspermy in vitro that are characterized by excessive sperm-zona binding and a delay in pronuclei(PN)*** staining and oocyte activation testing revealed that virtually all spermatozoa from patients lacked functional PLCζ and were thus unable to evoke Ca^(2+) *** with an artificial oocyte activation treatment successfully rescued the polyspermic phenotype and resulted in a live ***,we analyzed PLCζ in an additional 58 males after cIVF treatment in the Reproductive and Genetic Hospital of CiTiC-Xiangya(Changsha,China)between February 2019 and January *** found that the proportion of spermatozoa that expressed PLCζ was positively correlated with both 2PN rate and total *** optimal cutoff value below which males were likely to experience low FR(total FR≤30%)after clVF was 56.7%for the proportion of spermatozoa expressing *** study expands the mutation and the phenotypic spectrum of PLCZ1 and further suggests that PLCζ constitutes a promising biomarker for identifying low FRs cases in cIVF due to sperm-related oocyte activation deficiency and that sperm PLCζ analysis may benefit the widermale population and not onlymen with IcsI failure.

关键词： conventional IVF gene variants PLCζ polyspermy

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活塞机械疲劳试验的三维接触有限元仿真

山东理工大学学报（自然科学版） 2006年第2期20卷 68-72页

作者：门秀花王延遐山东理工大学交通与车辆工程学院山东淄博255049

针对某活塞机械疲劳试验,以某铝合金活塞为研究对象,采用有限元方法分析了在交变机械载荷作用下活塞销和活塞销座内侧之间接触状态和接触应力的变化,在此基础上确定了活塞疲劳失效的主要位置,这一数值计算结果与试验结果吻合,进而分析... 详细信息

针对某活塞机械疲劳试验,以某铝合金活塞为研究对象,采用有限元方法分析了在交变机械载荷作用下活塞销和活塞销座内侧之间接触状态和接触应力的变化,在此基础上确定了活塞疲劳失效的主要位置,这一数值计算结果与试验结果吻合,进而分析了接触对活塞疲劳失效的影响.

关键词：活塞机械负荷接触分析瞬态动力分析有限元分析

基于基本概念的理论力学网络自学辅导课件的研制

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高等建筑教育 2005年第1期14卷 90-92页

作者：王延遐门秀花山东理工大学交通学院山东淄博255012

针对教学中普遍存在的学生对基本概念掌握含糊不清的问题 ,以Authorware为开发工具制作了基于基本概念的理论力学网络自学辅导课件。此课件总结了各章的重点内容和难点内容 ,并建立了自测系统 ,为学生学习和掌握本门课程提供了较好的条件。

关键词：基本概念理论力学 CAI 模块式

Genetic mutation of Tas2r104/Tas2r105/Tas2r114 cluster leads to a loss of taste perception to denatonium benzoate and cucurbitacin B

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Animal Models and Experimental Medicine 2024年第3期7卷 324-336页

作者： Bowen Niu Lingling Liu Qian Gao meng-Min Zhu Lixiang Chen xiu-hua Peng Boying Qin Xiaohui Zhou Feng Li Department of Laboratory Animal Science Shanghai Public Health Clinical CenterFudan UniversityShanghaiChina Department of Biology College of Life SciencesShanghai Normal UniversityShanghaiPeople's Republic of China

Background:Bitter taste receptors(Tas2rs)are generally considered to sense various bitter compounds to escape the intake of toxic *** taste receptors have been found to widely express in extraoral tissues and have important physiological functions outside the gustatory system in ***:To investigate the physiological functions of the bitter taste receptor cluster Tas2r106/Tas2r104/Tas2r105/Tas2r114 in lingual and extraoral tissues,multiple Tas2rs mutant mice and Gnat3 were produced using CRISPR/Cas9 gene-editing technique.A mixture containing Cas9 and sgRNA mRNAs for Tas2rs and Gnat3 gene was microinjected into the cytoplasm of the ***,T7EN1 assays and sequencing were used to screen genetic mutation at the target sites in founder *** real-time polymerase chain reaction(qRT-PCR)and immunostaining were used to study the expression level of taste signaling cascade and bitter taste receptor in taste *** to taste substance was also studied using twobottle preference ***:We successfully produced several Tas2rs and Gnat3 mutant mice using the CRISPR/Cas9 *** results showed that the expression of GNAT3 and PLCB2 was not altered in Tas2rs mutant *** qRT-PCR results revealed the changed expression profile of m Tas2rs gene in taste buds of these mutant *** two-bottle preference tests,these mutant mice eliminate responses to cycloheximide due to genetic mutation of *** addition,these mutant mice showed a loss of taste perception to quinine dihydrochloride,denatonium benzoate,and cucurbitacin B(CuB).Gnat3-mediated taste receptor and its signal pathway contribute to CuB ***:These findings implied that these mutant mice would be a valuable means to understand the biological functions of TAS2Rs in extraoral tissues and investigate bitter compound-induced responses mediated by these TAS2Rs in many extraoral tissues.

关键词： bitter taste receptor CRISPR/Cas9 genetic mutation two-bottle preference test type 2 taste receptors(Tas2rs)

Effect of male HBV infection on the outcomes of IVF/ICSI cycles:a retrospective cohort study based on propensity score matching

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Asian Journal of Andrology 2024年第4期26卷 415-420页

作者： Su-Qin Zhu xiu-hua Liao Wen-Wen Jiang Yan Sun Hui-Ling Xu Xiao-Jing Chen Bei-Hong Zheng Fujian Provincial Reproductive Medicine Center Fujian Maternity and Child Health HospitalCollege of Clinical Medicine for Obstetrics and Gynecology and PediatricsFujian Medical UniversityFuzhou 350001China Fujian Key Laboratory of Prenatal Diagnosis and Birth Defect Fuzhou 350001China Fujian Maternal-Fetal Clinical Medicine Research Center Fuzhou 350001China.

This study aimed to investigate the effects of male hepatitis B virus(HBV)infection on male fertility,embryonic development,and in vitro fertilization/intracytoplasmic sperm injection(IVF/ICSI)*** performed a retrospective cohort study that included 3965 infertile couples who received fresh embryo transfer cycles for the first time at the Fujian Maternity and Child Health Hospital(Fuzhou,China)from January 2018 to January *** couples were categorized based on their HBV infection status into the HBV group(HBV-positive men and HBV-negative women)and the control group(HBV-negative couples).A 1:1 propensity score matching was performed with relatively balanced *** characteristics,semen parameters,laboratory outcomes,clinical outcomes,and obstetric and neonatal outcomes were compared between *** propensity score matching,821 couples were included in each *** groups had similar semen parameters and obstetric and neonatal *** HBV group showed a significantly lower live birth rate than the control group(Pmen with IVF/ICSI does not increase with male HBV infection.

关键词： hepatitis B virus in vitro fertilization intracytoplasmic sperm injection live birth rate propensity score matching

Adrenocorticotropic hormone combined with magnesium sulfate therapy for infantile epileptic spasms syndrome:a real-world study

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World Journal of Pediatrics 2024年第8期20卷 834-847页

作者： Wen He Qiu-Hong Wang Jiu-Wei Li Yang-Yang Wang Xiao-Mei Luo Lin Wan Jing Wang xiu-Yu Shi Wei-hua Zhang Fang Fang Li-Ping Zou Senior Department of Pediatrics the Seventh Medical Center of Chinese PLA General HospitalDepartment of Pediatricsthe First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Neurology Beijing Children’s HospitalCapital Medical UniversityBeijingChina Center of Epilepsy Beijing Institute for Brain DisordersBeijing 100069China

Background Infantile epileptic spasms syndrome(IESS)is a serious disease in infants,and it usually evolves to other epilepsy types or syndromes,especially refractory or super-refractory focal *** adrenocorticotropic hormone(ACTH)is one of the first-line and effective treatment plans for IESS,it has serious side effects and is not sufficiently *** A retrospective study of the clinical outcomes of ACTH combined with magnesium sulfate(MgSO4)therapy for IESS in two hospital centers was *** major outcome of the single and combined treatment was evaluated by changes in seizure frequency and improvements in hypsarrhythmia electroencephalography(EEG).To reduce the confounding bias between the two groups,we used SPSS for the propensity score matching(PSM)*** We initially recruited 1205 IESS patients from two Chinese hospitals and treated them with ACTH combined with MgSO4 and ACTH *** 1005 patients were enrolled in the treatment(ACTH combined with MgSO4:744,ACTH:261),and both treatment plans had a more than 55%response ***,compared to patients treated with ACTH alone,those patients treated with ACTH combined with MgSO4 had better performance in terms of the seizure frequency and hypsarrhythmia *** PSM,the two groups also showed significant differences in responder rate[70.8%(95%confidence interval,CI)=66.7%–74.8%)vs.53.8%(95%CI=47.4%–60.2%),Pment and the number of antiseizure medications taken before treatment were two factors that may affect the clinical *** with less than 3 months of lead time responded to the treatment much better than those with>3 months(Pment,only

关键词： Adrenocorticotropic hormone Clinical trial Infantile epileptic spasms syndrome Magnesium sulfate Real-world study

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活塞组机械疲劳试验的有限元仿真

拖拉机与农用运输车 2006年第4期33卷 20-22页

作者：刘永启王延遐门秀花林风华张运泰山东理工大学交通与车辆工程学院山东淄博255049 山东滨州渤海活塞股份有限公司山东滨洲256602

对某铝合金活塞在机械疲劳试验机上做的疲劳试验进行有限元分析,为活塞的改进设计提供依据。采用装有活塞销的三维整体活塞有限元模型,应用接触单元模拟实际情况,对活塞在交变机械载荷作用下的应力和应变进行了计算,找出了危险点部位,... 详细信息

对某铝合金活塞在机械疲劳试验机上做的疲劳试验进行有限元分析,为活塞的改进设计提供依据。采用装有活塞销的三维整体活塞有限元模型,应用接触单元模拟实际情况,对活塞在交变机械载荷作用下的应力和应变进行了计算,找出了危险点部位,计算结果与试验吻合。

关键词：活塞机械负荷接触瞬态有限元分析

Comparative analysis of primate and pig cells reveals primate-specific PINK1 expression and phosphorylation

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Zoological Research 2024年第2期45卷 242-252页

作者： xiu-Sheng Chen Rui Han Yan-Ting Liu Wei huang Qi Wang Xin Xiong Ying Zhang Jian-Guo Zhao Shi-hua Li Xiao-Jiang Li Wei-Li Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)GHM Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong 510632China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

PTEN-induced putative kinase 1(PINK1),a mitochondrial kinase that phosphorylates Parkin and other proteins,plays a crucial role in mitophagy and protection against *** in PINK1 and Parkin can lead to loss of function and early onset Parkinson's ***,there is a lack of strong in vivo evidence in rodent models to support the theory that loss of PINK1 affects mitophagy and induces ***,PINK1 knockout pigs(Sus scrofa)do not appear to exhibit *** our recent work involving non-human primates,we found that PINK1 is selectively expressed in primate brains,while absent in rodent *** extend this to other species,we used multiple antibodies to examine the expression of PINK1 in pig *** contrast to tissues from cynomolgus monkeys(Macaca fascicularis),our data did not convincingly demonstrate detectable PINK1expression in pig *** of PINK1 in cultured pig cells did not result in altered Parkin and BAD phosphorylation,as observed in cultured monkey cells.A comparison of monkey and pig striatum revealed more PINK1-phosphorylated substrates in the monkey ***,PINK1 knockout in pigs did not lead to obvious changes in the phosphorylation of Parkin and *** findings provide new evidence that PINK1expression is specific to primates,underscoring the importance of non-human primates in investigating PINK1function and pathology related to PINK1 deficiency.

关键词： PINK1 Parkin Mitochondria Phosphorylation Non-human primates Pigs