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Sperm banking for male reproductive preservation： a 6-year retrospective multi-centre study in China

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Asian Journal of Andrology 2010年第3期12卷 356-362,I0009页

作者： Ping Ping Wen-Bing Zhu Xin-Zong Zhang kang-shou yao Peng Xu Yi-Ran Huang Zheng Li Department of Urology Shanghai Human Sperm Bank Shanghai Institute of Andrology Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200001 China Instinrte of Human Reproduction and Stem Cell Engineering Human Sperm Bank Central South University Changsha 410078 China Zhejiang Institute of Planned Parenthood Research ＆ Zhejiang Human Sperm Bank Hangzhou 310012 China jinghua Hospital Shenyang East Group Shenyang Reproductive Medicine Centre Shenyang 110005 China

Sperm banking can preserve male fertility effectively, but the current conditions of sperm cryopreservation in China have not been investigated. This retrospective investigation was based on data collected at multiple centres in China from January 2003 to December 2008. The collected data included urogenital history, indication for cryopreservation, semen parameters, use rate, type of assisted reproductive technique （ART） treatment and pregnancy outcome. The study population included 1 548 males who had banked their semen during the study period at one of the clinics indicated above. Approximately 1.9% （30/1 548） of the cryopreserved semen samples were collected from cancer patients; about 88.8% （1 374/1 548） of the patients had banked their semen for ART and 8.6% （134/1 548） had a male infertility disease （such as anejaculation, severe oligozoospermia and obstructive azoospermia）. The total use rate of cryopreserved semen was 22.7% （352/1 548）, with 119 live births. The cancer group use rate was 6.7% （2/30）, with one live birth by intracytoplasmic single sperm injection （ICSI）. The ART group use rate was 23.2% （319/1 374）, with 106 live births. The reproductive disease group use rate was 23.1% （31/134）, with 12 live births. The semen parameters in each category varied; the cancer patient and infertility disease groups had poor semen quality. In vitro fertilization （IVF） and ICSI were the most common ART treatments for cryopreserved sperm. Semen cryopreservation as a salvage method is effective, but in many conditions it is underutilized, especially in cancer patients. Lack of awareness, urgency of cancer treatment and financial constraints are the main causes of the low access rate. The concept of fertility preservation should be popularized to make better use of this medical service in China.

关键词： cancer cryopreservation infertility sperm

Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers

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Petroleum Science 2024年第1期21卷 430-444页

作者： Yu-Ning Yong Zhao-Quan Guo shou-Ceng Tian Lu-yao Ma Tian-Yu Wang Mao Sheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Beijing Petroleum Machinery Company Limited CNPC Engineering Technology R&D Company LimitedBeijing102206China Smart Energy Co. LtdChina Xiongan GroupXiong’an New Area071000HebeiChina

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas *** paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing *** crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are *** results show that radial borehole fracturing in multiple layers generates diverse fracture *** types of fractures are identified based on the connectivity between hydraulic fractures and radial *** vertical distance significantly influences fracture propagation perpendicular to the radial borehole *** increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole *** azimuth also influences fracture propagation along the radial borehole *** the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress *** breakdown pressure correlates with diverse fracture geometries *** the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown *** the azimuth and increasing the diameter also decrease the breakdown *** extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown *** research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and g

关键词： Multi-layer radial boreholes Hydraulic fracturing Fracture propagation Pressure characteristic

Surface crack evolution patterns in freeze-thaw damage of fissured rock bodies

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Journal of Mountain Science 2024年第9期21卷 3094-3107页

作者： kang Zhiqiang WANG Zhilei SHAO Luhang FENG Jiangjiang yao Xulong College of Mining Engineering North China University of Science and TechnologyTangshan 063200China Green Intelligent Mining Technology Innovation Center of Hebei Province North China University of Science and TechnologyTangshan 063210China Luannan Macheng Mining Co. Ltd.Shougang Group Co.LtdLuannan CountyTangshan 063500China

To explore the effects of freeze‒thaw cycles on the mechanical properties and crack evolution of fissured sandstone,biaxial compression experiments were carried out on sandstone subjected to freeze‒thaw cycles to characterize the changes in the physical and mechanical properties of fissured sandstone caused by freeze‒thaw *** crack evolution and crack change process on the surface of the fissured sandstone were recorded and analysed in detail via digital image technology(DIC).Numerical simulation was used to reveal the expansion process and damage mode of fine-scale cracks under the action of freeze‒thaw cycles,and the simulation results were compared and analysed with the experimental data to verify the reliability of the numerical *** results show that the mass loss,porosity,peak stress and elastic modulus all increase with increasing number of freeze‒thaw *** an increase in the number of freeze‒thaw cycles,a substantial change in displacement occurs around the prefabricated cracks,and a stress concentration appears at the crack *** new cracks continue to sprout at the tips of the prefabricated cracks until the microcracks gradually penetrate into the main cracks,the displacement cloud becomes obviously discontinuous,and the contours of the displacement field in the crack fracture damage area simply intersect with the prefabricated cracks to form an obvious *** damage patterns of the fractured sandstone after freeze‒thaw cycles clearly differ,forming a symmetrical"L"-shaped damage pattern at zero freeze‒thaw cycles,a symmetrical"V"-shaped damage pattern at 10 freeze‒thaw cycles,and a"V"-shaped damage pattern at 20 freeze‒thaw *** 20 freeze‒thaw cycles,a"V"-shaped destruction pattern and"L"-shaped destruction pattern are formed;after 30 freeze‒thaw cycles,an"N"-shaped destruction pattern is *** shows that the failure mode of fractured sandstone gradually becomes more complicated with an increasing number of freeze‒t

关键词： Freeze‒thaw cycles Fissured sandstone Particle flow software Rock mechanics Crack extension pattern DIC technique

Effect of acacetin on inhibition of apoptosis in Helicobacter pyloriinfected gastric epithelial cell line

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3624-3634页

作者： Qi-Xi yao Zi-Yu Li Hou-Le kang Xin He Min kang Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Orthopaedics The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Emergency Luzhou People’s HospitalLuzhou 646000Sichuan ProvinceChina

BACKGROUND Helicobacter pylori(***)infection can cause extensive apoptosis of gastric epithelial cells,serving as a critical catalyst in the progression from chronic gastritis,gastrointestinal metaplasia,and atypical gastric hyperplasia to gastric *** eradication of *** is paramount for ameliorating the pathophysiological conditions associated with chronic inflammation of the gastric mucosa and the primary prevention of gastric ***,which has multifaceted pharmacological activities such as anti-cancer,anti-inflammatory,and antioxidative properties,has been extensively investigated across various ***,the impact and underlying mechanisms of action of acacetin on ***-infected gastric mucosal epithelial cells remain *** To explore the defensive effects of acacetin on apoptosis in ***-infected GES-1 cells and to investigate the underlying *** GES-1 cells were treated with *** and acacetin in *** viability was assessed using the CCK-8 assay,cell mortality rate via lactate dehydrogenase assay,alterations in cell migration and healing capacities through the wound healing assay,rates of apoptosis via flow cytometry and TUNEL staining,and expression levels of apoptosis-associated proteins through western blot *** *** infection led to decreased GES-1 cell viability,increased cell mortality,suppressed cell migration,increased rate of apoptosis,increased expressions of Bax and cle-caspase3,and decreased Bcl-2 ***,acacetin treatment enhanced cell viability,mitigated apoptosis induced by *** infection,and modulated the expression of apoptosis-regulatory proteins by upregulating Bcl-2 and downregulating Bax and cleaved *** Acacetin significantly improved GES-1 cell viability and inhibited apoptosis in ***-infected GES-1 cells,thereby exerting a protective effect on gastric mucosal epithelial cells.

关键词： Gastric epithelial GES-1 cells Helicobacter pylori Infection Acacetin Antibiotic resistance Apoptosis

Experimental and numerical study on protective effect of RC blast wall against air shock wave

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Defence Technology（防务技术） 2024年第1期31卷 567-579页

作者： Xin-zhe Nian Quan-min Xie Xin-li Kong Ying-kang yao Kui Huang State Key Laboratory of Precision Blasting Jianghan UniversityWuhan430056China Hubei Key Laboratory of Blasting Engineering Jianghan UniversityWuhan430056China Hubei(Wuhan)Institute of Explosion and Blasting Technology Jianghan UniversityWuhan430056China College of Defense Engineering Army Engineering University of PLANanjing210007China Institute of Defense Engineering AMSPLALuoyang471023China

Prototype experiments were carried out on the explosion-proof performance of the RC blast *** mass of TNT detonated in the experiments is 5 kg and 20 kg *** shock wave overpressure was tested in different *** above experiments were numerically simulated,and the simulated shock wave overpressure waveforms were compared with that tested and given by CONWEP *** results show that the numerically simulated waveform is slightly different from the test waveform,but similar to CONWEP *** dimensional analysis and numerical simulation under different working conditions,the equation for the attenuation rate of the diffraction overpressure behind the blast wall was *** to the corresponding standards,the degree of casualties and the damage degree of the brick concrete building at a certain distance behind the wall can be determined when parameters are *** above results can provide a reference for the design and construction of the reinforced concrete blast wall.

关键词： Blast wall Shock wave Diffraction Overpressure Protection

Unraveling engineering disturbance effects on deformation in red-bed mudstone railway cuttings:incorporating crack-facilitated moisture diffusion

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Journal of Mountain Science 2024年第5期21卷 1663-1682页

作者： HUANG kang DAI Zhangjun YAN Chengzeng yao Junkai CHI Zecheng CHEN Shanxiong State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Faculty of Engineering China University of GeosciencesWuhan 430074China International Joint Research Center for Deep Earth Drilling and Resource Development China University of GeosciencesWuhan 430074China China Academy of Railway Sciences Corporation Limited Beijing 100081China

Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in expansion, deformation, and cracking upon exposure to moisture. This study addresses uplift deformation disasters in high-speed railways by employing a moisture diffusion-deformation-fracture coupling model based on the finite-discrete element method(FDEM). The model integrates the influence of cracks on moisture diffusion. The investigation into various excavation depths reveals a direct correlation between depth and the formation of tensile cracks at the bottom of the railway cutting. These cracks expedite moisture migration, significantly impacting the temporal and spatial evolution of the moisture field. Additionally, crack expansion dominates hygroscopic deformation, with the lateral coordinate of the crack zone determining peak vertical displacement. Furthermore, key factors influencing deformation in railway cuttings, including the swelling factor and initial moisture content at the bottom of the cutting, are explored. The number of tensile and shear cracks increases with greater excavation depth, particularly concerning shear cracks. Higher swelling factors and initial moisture contents result in an increased total number of cracks, predominantly shear cracks. Numerical calculations provide valuable insights, offering a scientific foundation and directional guidance for the precise prevention, control, prediction, and comprehensive treatment of mudstone-related issues in high-speed railways.

关键词： Red-bed mudstone Railway cutting FDEM Moisture diffusion Deformation Crack

Single-atom Rh catalysts for efficiently degrading Rhodamine B with high concentration

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Rare Metals 2024年第5期43卷 2331-2338页

作者： shou-yao Hu Jian-Ping Guan Run-Ze Ma Yu Tao Dong-Hao Liu Jia-Xin Gong Yu Xiong Department of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

Highly concentrated dye wastewater has a serious effect on the quality of natural waters;thus,developing novel catalysts to degrade dyes rapidly and efficiently is of great *** the first time,this study reports an Rh single atom loaded on a nitrogen-doped carbon(SA-Rh/CN)*** catalyst exhibits an excellent processing capacity for high concentrations of Rhodamine B(Rh B),high catalytic activity(95.7% degradation of Rh B in60 min)and excellent stability(93.5% degradation efficiency after 10 stable runs).

关键词： catalyst. catalysts loaded

Bifunctional Silicon Quantum Dots for Antibacterial Application and Highly Sensitive Detection of Tetracycline

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Journal of Analysis and Testing 2024年第2期8卷 218-227页

作者： Shuiqin Chai Yuting Chi Wanlin Sun Xinyu Pei Shuchen Pei Chengyu Sun kang Luo Bo yao College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China People’s Hospital Affiliated to Chongqing Three Gorges Medical CollegeChongqing404037China

Silicon quantum dots(SiQDs)with high water-soluble and favorable photostability were prepared by a one-step hydrothermal *** average diameter of SiQDs was 2.02 nm characterized by transmission electron *** was to be noted that the as-prepared SiQDs showed eff ective antibacterial activity,which was attributed to electrostatic interaction and the generation of reactive oxygen *** minimum inhibitory concentration of SiQDs against Escherichia coli and Staphylococcus aureus was 0.45 mg/mL and 0.38 mg/mL,***,based on the static quenching eff ect-induced fluorescence quenching mechanism,the SiQDs exhibited high sensitivity and selectivity for detecting tetracyclines(TC).A good linear relationship was obtained between the fluorescence intensity of SiQDs and the concentration of tetracycline(TC)in the range of 0–0.08μmol/L(R^(2)=0.9993)with a detection limit of 0.0176μmol/***,the TC content in the honey samples was determined using the *** the results suggest that the as-prepared SiQDs can be a potential fluorescent probe for application in antibacterial and analysis.

关键词： Silicon quantum dots Antibacterial activity Reactive oxygen species Tetracycline detection

Diarrhea induced by insufficient fat absorption in weaned piglets:Causes and nutrition regulation

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Animal Nutrition 2024年第01期16卷 299-305页

作者： Yuying Li Pengjun Shi kang yao Qian Lin Mansheng Wang Zhenping Hou Wenjie Tang Hui Diao Institute of Bast Fiber Crops Chinese Academy of Agricultural Sciences Institute of Subtropical Agriculture Chinese Academy of Sciences Hunan Province Key Laboratory of Animal Nutritional Physiology and Metabolic Process Animal Breeding and Genetics Key Laboratory of Sichuan Province Livestock and Poultry Biological Products Key Laboratory of Sichuan Province Sichuan Animal Science Academy Sichuan Animtech Feed Co. Ltd

Fat is one of the three macronutrients and a significant energy source for piglets. It plays a positive role in maintaining intestinal health and improving production performance. During the weaning period,physiological, stress and diet-related factors influence the absorption of fat in piglets, leading to damage to the intestinal barrier, diarrhea and even death. Signaling pathways, such as fatty acid translocase(CD36), pregnane X receptor(PXR), and AMP-dependent protein kinase(AMPK), are responsible for regulating intestinal fat uptake and maintaining intestinal barrier function. Therefore, this review mainly elaborates on the reasons for diarrhea induced by insufficient fat absorption and related signaling pathways in weaned-piglets, with an emphasis on the intestinal fat absorption disorder. Moreover, we focus on introducing nutritional strategies that can promote intestinal fat absorption in piglets with insufficient fat absorption-related diarrhea, such as lipase, amino acids, and probiotics.

关键词： Weaned piglet Diarrhea Fat absorption Nutrient regulation