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Altered microRNA expression profiles of human spermatozoa in normal fertile men of different ages

Asian Journal of Andrology 2023年第6期25卷 737-744页

作者： Ming-Jia Zhao Yao-Nan Zhang Yong-Ping Zhao Xian-Bing Chen bao-sheng han Ning Ding Yi-Qun Gu Shu-Song Wang Jing Ma Mei-Ling Liu Graduate School of Peking Union Medical College Peking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100730China National Health Commission Key Laboratory of Male Reproductive Health National Research Institute for Family PlanningBeijing 100081China Department of Reproduction and Genetics Maternity and Child Health Care HospitalTangshan 063000China Department of Family Planning and Reproductive Medicine Peking University People’s HospitalBeijing 100081China Hebei Key Laboratory of Reproductive Medicine Hebei Institute of Reproductive Health Science and TechnologyShijiazhuang 050071China

MicroRNAs(miRNAs)are mediators of the aging process.The purpose of this work was to analyze the miRNA expression profiles of spermatozoa from men of different ages with normal fertility.Twenty-seven donors were divided into three groups by age(Group A,n=8,age:20–30 years;Group B,n=10,age:31–40 years;and Group C,n=9,age:41–55 years)for high-throughput sequencing analysis.Samples from 65 individuals(22,22,and 21 in Groups A,B,and C,respectively)were used for validation by quantitative real-time polymerase chain reaction(qRT-PCR).A total of 2160 miRNAs were detected:1223 were known,937 were newly discovered and unnamed,of which 191 were expressed in all donors.A total of 7,5,and 17 differentially expressed microRNAs(DEMs)were found in Group A vs B,Group B vs C,and Group A vs C comparisons,respectively.Twenty-two miRNAs were statistically correlated with age.Twelve miRNAs were identified as age-associated miRNAs,including hsa-miR-127-3p,mmu-miR-5100_L+2R-1,efu-miR-9226_L-2_1ss22GA,cgr-miR-1260_L+1,hsa-miR-652-3p_R+1,pal-miR-9993a-3p_L+2R-1,hsa-miR-7977_1ss6AG,hsa-miR-106b-3p_R-1,hsa-miR-186-5p,PC-3p-59611_111,hsa-miR-93-3p_R+1,and aeca-mir-8986ap5_1ss1GA.There were 9165 target genes of age-associated miRNAs.Gene Ontology(GO)analysis of the target genes identified revealed enrichment of protein binding,membrane,cell cycle,and so on.The Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis of age-related miRNAs for target genes revealed 139 enriched pathways,such as signaling pathways regulating stem cell pluripotency,metabolic pathways,and the Hippo signaling pathway.This suggests that miRNAs play a key role in male fertility changes with increasing age and provides new evidence for the study of the mechanism of age-related male fertility decline.

关键词： age fertility microRNA spermatozoa

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Advantages and limitations of the parthenogenetic embryonic stem cells in cell therapy

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Journal of Reproduction and Contraception 2016年第2期27卷 118-124页

作者： Zhao-yang YU bao-sheng han North China University of Science and Technology Department of Reproduction and Genetics Maternity and Child Health Care HospitalTangshan

Parthenogenetic embryonic stem cells（pE SCs）, as ＂seed cells＂ for regenerative medicine, are an effective way to build patient-specific pluripotent stem cells, due to the fact that characteristics of self-renewal and pluripotent are similar to embryonic stem cells（ESCs）. Parthenogenetic activation can be performed at meiosis I or meiosis II describing the embryos with distinct patterns of homozygosity and heterozygosity.Heterozygous pE SCs are expected to be used for autologous transplantation, while homozygous pE SCs enable to be used for allogeneic gene therapy in theory but is hampered by immunological barriers defined by the recognition of natural killer（NK）cells. In this review, we describe the mechanism of deriving heterozygous and homozygous pE SCs, and summarize the advantages and limitations of pE SCs in the area of cell therapy.

关键词： parthenogenetic embryonic stem cells（pESCs） heterozygous homozygous advantages and limitations cell therapy

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Correlation of body mass index with Th1/Th2 balance, adhesion molecules and insulin signal transduction in infertile patients

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Journal of Hainan Medical University 2017年第21期23卷 60-63页

作者： Hui-Juan Zhang bao-sheng han Gui-Ling Fan Nv Geng Juan Li Dong-Ting Liu Department of Reproductive Genetics Tangshan Maternal and Child Health Hospital in Hebei ProvinceTangshan CityHebei Province063000 Department of Obstetrics and Gynecology Tangshan Maternal and Child Health Hospital in Hebei ProvinceTangshan CityHebei Province063000

Objective: To study the correlation of body mass index with Th1/Th2 balance, adhesion molecules and insulin signal transduction in infertile patients. Methods: A total of 132 patients who received diagnostic curettage due to infertility in Tangshan Maternal and Child Health Hospital between June 2015 and March 2016 were selected as the research subjects and divided into the normal group with BMI 30 kg/m2 according to BMI, and the levels of Th1/Th2 cytokines in serum as well as the expression of Th1/Th2 transcription factors, adhesion molecules and insulin signal pathway molecules in endometrial tissue were detected. Results:IFN-γ and TNF-α levels in serum of obesity group and overweight group were significantly higher than those of control group while IL-4, IL-5 and IL-13 levels in serum as well as CD44V6, N-cadherin, FAK, ICAM-1, GLUT-4, IRS-1, PI3K and AKT mRNA expression in endometrial tissue were significantly lower than those of control group;IFN-γ and TNF-α levels in serum of obesity group were significantly higher than those of overweight group while IL-4, IL-5 and IL-13 levels in serum as well as CD44V6, N-cadherin, FAK, ICAM-1, GLUT-4, IRS-1, PI3K and AKT mRNA expression in endometrial tissue were significantly lower than those of overweight group. Conclusion: Weight gain can aggravate the Th1/Th2 disorder, reduce the adhesion molecule expression and hinder the insulin signal transduction in infertile patients.

关键词： Infertility Body mass index Immune response Adhesion molecule Insulin resistance

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Energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1095-1103页

作者： bao-chen han Chun-liang Gao Ya-qiang Li Dan Liu Guang-sheng Wei Rong Zhu Hebei Key Laboratory of Material Near-Net Forming Technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving technologies.Therefore,a special converter smelting technology incorporating energy saving was proposed.To evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic model.Calculations reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy recovery.The application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan investment.Sensitivity analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the technology.As the discount rate increased,the cost of conserved energy also gradually increased.Overall,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology Energy saving Techno-economic model Investment cost

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Hybrid tri-memristor hyperchaotic map and application in Wasserstein Generative Adversarial Nets

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Science China Technological Sciences 2024年第6期67卷 1855-1865页

作者： GU Yang bao han YU XiHong HUA ZhongYun bao BoCheng XU Quan School of Microelectronics and Control Engineering Changzhou University School of Computer Science and Technology Harbin Institute of Technology

Inspired by basic circuit connection methods, memristors can also be utilized in the construction of complex discrete chaotic systems. To investigate the dynamical effects of hybrid memristors, we propose two hybrid tri-memristor hyperchaotic(HTMH)mapping structures based on the hybrid parallel/cascade and cascade/parallel operations, respectively. Taking the HTMH mapping structure with hybrid parallel/cascade operation as an example, this map possesses a spatial invariant set whose stability is closely related to the initial states of the memristors. Dynamics distributions and bifurcation behaviours dependent on the control parameters are explored with numerical tools. Specifically, the memristor initial offset-boosting mechanism is theoretically demonstrated, and memristor initial offset-boosting behaviours are numerically verified. The results clarify that the HTMH map can exhibit hyperchaotic behaviours and extreme multistability with homogeneous coexisting infinite attractors. In addition, an FPGA hardware platform is fabricated to implement the HTMH map and generate pseudorandom numbers(PRNs)with high randomness. Notably, the generated PRNs can be applied in Wasserstein generative adversarial nets(WGANs) to enhance training stability and generation capability.

关键词： memristor hybrid tri-memristor map spatial invariant set hyperchaos extreme multistability generative adversarial nets

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Aging Precipitates and Strengthening Mechanism of T122 Boiler Steel

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Journal of Iron and Steel Research(International) 2010年第2期17卷 67-73页

作者： bao han-sheng CHENG Shi-chang LIU Zheng-dong TAN Shu-ping Institute of Structure Materials Central Iron and Steel Research Institute Beijing 100081 China School of Astronautics Harbin Institute of Technology Harbin 150001 Heilongjiang China

T122 steel has been used to produce superheater or reheater of ultra supercritical boilers. With the help of chemical phase extraction and mierostructure characterization, the performance of aging precipitates of T122 steel, such as M23C6 carbide, Laves phase and MX phase was investigated, the strengthening mechanism of the steel was discussed, and the thermal yield stress of lath substructure, dislocations and precipitates of the steel were calculated. It was found that lath substructure and dislocations dominated the strengthening attribution and precipitation hardening went second to the strengthening attribution.

关键词： T122 heat resistant steel strengthening precipitate substructure dislocation

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Hot Deformation Behaviors of S31042 Austenitic Heat-Resistant Steel

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Journal of Iron and Steel Research(International) 2011年第10期18卷 54-58,79页

作者： WANG Jing-zhong LIU gheng-dong CHENG Shi-chang bao han-sheng Central Iron and Steel Research Institute Beijing 100081 China School ot Metallurgy and Engineering Xi＇ an University of Architecture and Technology Xi＇an 710055 Shaanxi China

The hot deformation behavior of S31042 austenitic heat-resistant steel was investigated over the tempera- ture range of 900--1 200 ℃ and strain rate range of 0.01--10 s- 1 using hot compression tests and the corresponding flow curves were obtained. The hot deformation activation energy of the test steel is 625 kJ/mol. The hot deformation equation and the relationship between the peak stresses, deformation temperature and strain rate were set up. The Zener-Hollomon parameter under various conditions was determined. The relation between the Zener-Hollomon parameter and the microstructure evolution of test steel was discussed. With the decrease of Zener-Hollomon param- eter, the microstructure of test steel transforms from deformation instability to dynamic recovery, partial dynamic recrystallization, full dynamic recrystallization with equiaxial structure, and finally to full dynamic recrystaUization with mixed crystal structure. The deformation condition can be adjusted easily by utilizing the Zener-Hollomon pa- rameter to obtain equiaxial microstructure.

关键词： S31042 steel hot deformation behavior Zener-Hollomon parameter microstructure

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Evolution of Precipitates of S31042 Heat Resistant Steel During 700℃ Aging

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Journal of Iron and Steel Research(International) 2013年第10期20卷 113-121页

作者： WANG Jing-zhong LIU Zheng-dong bao han-sheng CHENG Shi-chang Xi'an University of Architecture and Technology Central Iron and Steel Research Institute

The evolution of precipitates of S31042 steel during 700 ℃ aging was investigated by using a scanning elec- tron microscope, a transmission electron microscope, and electron energy spectrum technology. The various combi nations of M23C6, MX, NbCrN, and σ and G phases in the steel were found at different aging states. In the begin ning of aging, M23C6 precipitates swiftly along the grain boundaries. When the aging time exceeds 6 000 h, precipita- ted M23C6 carbides along the grain boundaries turn to be granular. It was found that Si element segregates to grain boundaries during above process, which may enhance the granular shape of M23C6 carbides and its transformation to and G phases. When the aging time exceeds 10 000 h, various shaped a phase and granular G phase appear along the grain boundaries and there are no continuous M23C6 carbides along the grain boundaries. Meanwhile, a large quantity of granular M23C6 carbides and a minor amount of G phase precipitate near the grain boundaries. Based on the segre- gation of silicon to the grain boundaries, a precipitation evolution model during aging was concluded.

关键词： S31042 heat resistant steel aging precipitation evolution

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Attaining synergetic equilibrium of electrical conductivity and tensile strength in GQDs@GN/Cu composites through multi-scale intragranular and intergranular reinforcements

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Rare Metals 2024年第1期43卷 366-379页

作者： Shuang-Yin Zhang Liang Liu Rui bao Jian-Hong Yi sheng-Da Guo Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and TechnologyKunming 650093China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

The configuration and quality of reinforcements, as well as the robustness of interfacial bonding,holding a critical significance in determining the concurrence between electrical conductivity and mechanical strength in metal matrix composites. In this study, citric acid was employed as the precursor for synthesizing multiscale carbon nanomaterials(graphene quantum dots and graphene, abbreviated as GQDs and GN). The GQDs@GN/Cu composites were fabricated through a segmented ball milling process in conjunction with subsequent spark plasma sintering(SPS). The intragranular GQDs and intergranular GQDs@GN had synergistically reinforced Cu composites through Orowan strengthening, load transfer strengthening and refinement strengthening. Furthermore,the robust interface bonding between GQDs@GN and Cu effectively mitigated interfacial impedance stemming from electron-boundary scattering. The yield strength and ultimate tensile strength of the GQDs@GN/Cu composites were recorded as 270 and 314 MPa, respectively, representing an improvement of 92 and 28% over pure Cu, while maintaining electrical conductivity at a level comparable to that of pure Cu. This study advances the understanding of the possibility of realizing a synergistic compatibility between electrical conductivity and mechanical strength in Cu composites.

关键词： Cu matrix composites Interface bonding Mechanical property Graphene quantum dots(GQDs) Electrical conductivity

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Effect of the Particle Packing Configuration on Fixed Bed Performance

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 152-160页

作者： Li Ziqi bao Di Zhou han Tang Xiaojin SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

Fixed-bed reactors are generally considered the optimal choice for numerous multi-phase catalytic reactions due to their excellent performance and stability.However,conventional fixed beds often encounter challenges related to inadequate mass transfer and a high pressure drop caused by the non-uniform void fraction distribution.To enhance the overall performance of fixed beds,the impact of different packing configurations on performance was investigated.Experimental and simulation methods were used to investigate the fluid flow and mass transfer performances of various packed beds under different flow rates.It was found that structured beds exhibited a significantly lower pressure drop per unit length than conventional packed beds.Furthermore,the packing configurations had a critical role in improving the overall performance of fixed beds.Specifically,structured packed beds,particularly the H-2 packing configuration,effectively reduced the pressure drop per unit length and improved the mass transfer efficiency.The H-2 packing configuration consisted of two parallel strips of particles in each layer,with strips arranged perpendicularly between adjacent layers,and the spacing between the strips varied from layer to layer.

关键词： packing configurations fixed bed Computational Fluid Dynamics simulation pressure drop mass transfer

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