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High-quality Cleavage Embryo versus Low-quality Blastocyst in Frozen-thawed Cycles:Comparison of Clinical Outcomes 被引量:3
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作者 Yu-lan WEI Bo HUANG +1 位作者 Xin-ling REN Lei JIN 《Current Medical Science》 SCIE CAS 2020年第5期968-972,共5页
This study compared the clinical outcomes of the frozen-thawed cycles of high-quality cleavage embryos with low-quality blastocysts to provide a reference for the choice of frozen-thawed embryo transfer schemes and to... This study compared the clinical outcomes of the frozen-thawed cycles of high-quality cleavage embryos with low-quality blastocysts to provide a reference for the choice of frozen-thawed embryo transfer schemes and to improve clinical pregnancy rates.A retrospective analysis was performed on the clinical data of patients undergoing frozen-thawed embryo transfer at the Reproductive Medicine Center of Tongji Hospital of Tongji Medical College of Huazhong University of Science and Technology from 2016 to 2017.In total,845 cases were divided into a high-quality cleavage embryo group(group A)and a low-quality blastocyst group(group B).Each group was further divided into subgroups based on the number of transplants.Group A was categorized into two subgroups comprising of 94 cases in subgroup Al(1 high-quality 8-cell group)and 201 cases in subgroup A2(2 high-quality 8-cell group).Group B was divided into four subgroups consisting of 73 cases in subgroup B I(D53BC group),65 cases in subgroup B2(D54BC group),110 cases in subgroup B3(D63BC group),and 282 cases in subgroup B4(D64BC group).The pregnancy outcomes and neonatal outcomes between the groups were compared.The clinical pregnancy rates(56.72%and 60.00%)and live birth rates(47.76%and 46.15%)in subgroups A2 and B2 showed no significant differences,but these rates were significantly higher in subgroups A2 and B2 than in the rest subgroups(P<0.05).The multiple birth rate(26.32%)in the subgroup A2 was significantly higher than that in the rest subgroups(P<0.05).There were no statistically significant differences in the abortion rates among all groups(P>0.05).In terms of neonatal outcomes,there were no statistically significant differences in the proportion of premature births,sex ratios,and birth defects among the low-weight and gigantic infants(P>0.05).Transplanting two high-quality cleavage embryos during the frozen-thawed embryo transfer cycles could significantly increase clinical pregnancy rates and live birth rates,but at the same time,it also increased the risks of multiple births and complications to mothers and infants.The D54BC subgroup had the most significant advantages among all groups(P<0.05).The rest low-quality blastocysts had clinical outcomes similar to the single high-quality cleavage embryo group. 展开更多
关键词 high-quality cleavage embryos low-quality blastocysts frozen-thawed transplantation clinical outcomes
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Comparison of Pregnancy Outcomes of High-Quality D5- and D6-Blastocyst Transfer in Hormone-Replacement Frozen-Thawed Cycles 被引量:1
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作者 Weijie Xing Liuhong Cai +1 位作者 Li Sun Jianping Ou 《International Journal of Clinical Medicine》 2017年第11期565-571,共7页
This study aimed to assess pregnancy outcomes after high-quality D5- and D6-blastocyst transfer in frozen cycles of in vitro fertilization and embryo transfer and to further evaluate whether there was a difference in ... This study aimed to assess pregnancy outcomes after high-quality D5- and D6-blastocyst transfer in frozen cycles of in vitro fertilization and embryo transfer and to further evaluate whether there was a difference in blastocyst development potentials with different developmental speeds and in pregnancy outcomes. A retrospective analysis was conducted to analyze 247 frozen cycles in our center from September 2015 to July 2017, which were divided into two groups: a D5-FET group with 193 cycles of D5-blastocyst transfer, and a D6-FET group with 54 cycles of D6-blastocyst transfer. Hormone replacement method was utilized to prepare frozen-cycle endometria. Pregnancy outcomes were analyzed and compared between these two groups. The mean ages of the two groups were 31.45 ± 4.43 years and 31.98 ± 4.84 years, respectively, with no statistically significant differences (P > 0.05). The difference in the endometrial thickness during transfer was also not statistically significant. The implantation rate in the D5-FET group was 60.13%, significantly higher than that in the D6-FET group (31.58%, P P < 0.05). No statistically significant differences were found in the abortion rate and ectopic pregnancy rate between the two groups. The implantation, biochemical pregnancy, and clinical pregnancy rates of the blastocyst D5 were all superior to those of the blastocyst D6. In clinics, therefore, D5-blastocyst transfer could be prioritized for embryo transfer. 展开更多
关键词 FROZEN cycle HORMONE REPLACEMENT Therapy BLASTOCYST Transfer
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Aerothermal performance of turbine during flight cycle based on fluid-thermal-structure multidisciplinary coupling method
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作者 Yunda ZHANG Zhengping ZOU +2 位作者 Chao FU Yifan WANG Jun ZENG 《Chinese Journal of Aeronautics》 2026年第1期35-54,共20页
The coupling effects among the flow field,temperature distribution and structural deformation in a turbine cannot be ignored,particularly during flight cycles when the turbine experiences varied operational states.Rel... The coupling effects among the flow field,temperature distribution and structural deformation in a turbine cannot be ignored,particularly during flight cycles when the turbine experiences varied operational states.Relying solely on steady-state solutions cannot predict the detrimental effects caused by hysteresis.Consequently,this paper employs a quasi-steady-state fluid-thermalstructure multidisciplinary coupling solution method,integrating transient solid heat conduction with steady-state flow field and static structural deformation solutions.After conducting a numerical simulation of a three-dimensional,five-stage,low-pressure turbine air system,the following conclusions are drawn:when boundary conditions attain high-power states through processes that are numerically identical but in opposite directions,slight variations in solid deformation significantly impact the flow field;when boundary conditions attain high-power states through processes that are directionally consistent but have different numerical values,the influence of the boundary condition change rate on the flow field surpasses that of solid deformation.In terms of turbine design parameters,a large difference in stage-reaction between adjacent stages at the lower radius of the turbine can lead to significant changes in the disc cavity flow field during flight cycles.The difference in the stage-reaction of 0.23 at 10%blade height in adjacent stages may induce severe gas ingress in the stator disc cavity.Thus,it is crucial to minimize this difference and to appropriately extend the duration of the deceleration phase to ensure the turbine's safe operation. 展开更多
关键词 Flight cycle Fluid-thermal-structure Multidisciplinary coupling Quasi-steady-state TURBINE
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Forecasting solar cycles using the time-series dense encoder deep learning model
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作者 Cui Zhao Shangbin Yang +1 位作者 Jianguo Liu Shiyuan Liu 《Astronomical Techniques and Instruments》 2026年第1期43-54,共12页
The solar cycle(SC),a phenomenon caused by the quasi-periodic regular activities in the Sun,occurs approximately every 11 years.Intense solar activity can disrupt the Earth’s ionosphere,affecting communication and na... The solar cycle(SC),a phenomenon caused by the quasi-periodic regular activities in the Sun,occurs approximately every 11 years.Intense solar activity can disrupt the Earth’s ionosphere,affecting communication and navigation systems.Consequently,accurately predicting the intensity of the SC holds great significance,but predicting the SC involves a long-term time series,and many existing time series forecasting methods have fallen short in terms of accuracy and efficiency.The Time-series Dense Encoder model is a deep learning solution tailored for long time series prediction.Based on a multi-layer perceptron structure,it outperforms the best previously existing models in accuracy,while being efficiently trainable on general datasets.We propose a method based on this model for SC forecasting.Using a trained model,we predict the test set from SC 19 to SC 25 with an average mean absolute percentage error of 32.02,root mean square error of 30.3,mean absolute error of 23.32,and R^(2)(coefficient of determination)of 0.76,outperforming other deep learning models in terms of accuracy and training efficiency on sunspot number datasets.Subsequently,we use it to predict the peaks of SC 25 and SC 26.For SC 25,the peak time has ended,but a stronger peak is predicted for SC 26,of 199.3,within a range of 170.8-221.9,projected to occur during April 2034. 展开更多
关键词 Solar cycle Forecasting TIDE Deep learning
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Durability of SAP-modified Fully Recycled Concrete under Freeze-Thaw Cycles
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作者 XING Zhengguang PENG Erxing +3 位作者 ZHANG Mingyi PEI Wansheng HU Xiaoying SUN Haoyue 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期179-188,共10页
This study introduces superabsorbent polymers(SAP)into recycled concrete and,through freeze-thaw cycle tests,unconfined compressive strength tests,and nuclear magnetic resonance(NMR)analysis,evaluates the freeze-thaw ... This study introduces superabsorbent polymers(SAP)into recycled concrete and,through freeze-thaw cycle tests,unconfined compressive strength tests,and nuclear magnetic resonance(NMR)analysis,evaluates the freeze-thaw resistance and durability of recycled concrete samples under varying freeze-thaw cycles.The results indicate that an appropriate addition of SAP significantly enhances the freeze-thaw resistance of recycled concrete.After 200 freeze-thaw cycles,the RS0.6 sample retained good surface integrity,demonstrating the best performance.Compared to NAC,its mass loss decreased by 1.16%,the relative dynamic modulus improved by 7.01%,and the compressive strength loss rate decreased by 5.41%.Additionally,T2 spectrum analysis revealed that adding SAP optimized the pore structure of recycled concrete and mitigated pore development during freeze-thaw cycles.As the number of freeze-thaw cycles increased,the RS0.3 and RS0.6 samples demonstrated superior frost resistance compared to NAC.However,an excessive amount of SAP increased pore expansion during subsequent freeze-thaw cycles,ultimately weakening frost resistance. 展开更多
关键词 Recycled concrete SAP freeze-thaw cycle pore structure DURABILITY
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The Fully Interactive Martian Dust Cycle Simulations by the GoMars Model
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作者 Shuai LIU Li DONG +9 位作者 Xiangyu XI Xuan CHENG Juanjuan LIU Ye PU Yiyuan LI Hongbo LIU Mingyu LIU Wei XUE Junji CAO Bin WANG 《Advances in Atmospheric Sciences》 2026年第3期461-476,共16页
The dust cycle is a crucial component of the present-day Martian climate system.This study examines its multitimescale variability using an optimized 50-year simulation with the fully interactive scheme from the Globa... The dust cycle is a crucial component of the present-day Martian climate system.This study examines its multitimescale variability using an optimized 50-year simulation with the fully interactive scheme from the Global Open Planetary Atmospheric Model for Mars(GoMars),a newly developed Mars General Circulation Model(MGCM).GoMars is able to reproduce the diurnal,seasonal,and interannual characteristics of the dust cycle in several key aspects,with high repeatability in diurnal and seasonal variations during non-global dust storm(non-GDS)years.The model’s“climatology”(non-GDS years ensemble mean)captures the seasonal pattern and magnitude of the vertical–meridional dust distribution,validated against Mars Climate Database and Mars Climate Sounder observations.In the absence of direct observations,the GoMars-simulated near-surface wind stress lifting flux is evaluated through comparisons with other MGCMs(e.g.,MarsWRF),revealing consistent seasonal and spatial patterns.As for the diurnal cycle,the peak dust devil lifting flux occurs at 1200–1300 local time,matching the Mars Pathfinder measurements.The model also successfully captures the intense dust devil activity in Amazonis,a region identified as a major dust devil hotspot based on observational data.In GDS years,GoMars effectively reproduces spontaneous GDSs,capturing their observed onset times,locations,and dust transport patterns as exhibited in specific Martian years.The model also simulates significant interannual variability,with irregular GDS intervals along with reasonable dust–atmosphere interactions. 展开更多
关键词 GoMars dust cycle fully interactive dust interannual variability
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Experimental study on damage evolution and failure precursor characteristics of granite under thermal shock cycles
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作者 Zhenjiang Huang Mingxuan Shen +5 位作者 Yu Zhao Chaolin Wang Jing Bi Yongfa Zhang Shuang Dang Yuhang Zhao 《International Journal of Mining Science and Technology》 2026年第1期125-148,共24页
Investigating the damage evolution of surrounding rock under thermal shock cycles is crucial for ensuring the stability of engineering rock masses.This study performed Brazilian splitting tests on granite specimens un... Investigating the damage evolution of surrounding rock under thermal shock cycles is crucial for ensuring the stability of engineering rock masses.This study performed Brazilian splitting tests on granite specimens under varying temperature and cycle conditions,employing acoustic emission monitoring,digital image correlation,and three-dimensional scanning technology.A systematic analysis was conducted on the patterns of damage evolution,failure precursor,and response mechanisms under combined thermal and cyclic loading.Experimental results show that both P-wave velocity and tensile strength degrade significantly with increasing temperature and cycle count,with temperature having a more pronounced effect than cycle count.Notably,damage evolution exhibits a dual-threshold behavior in which degradation accelerates markedly above 400℃ and stabilizes after 5 thermal cycles.Fracture surfaces evolve from initially planar to rugged morphologies,with peak-valley height differences at 600℃ being approximately three times greater than those at 200℃.Furthermore,based on acoustic emission energy entropy analysis,we introduce a novel failure precursor indicator where the sustained increase and critical surge in average entropy serve as reliable early-warning signals for impending rock failure.These findings establish a solid theoretical basis and practical methodology for damage assessment and instability early-warning systems in high-temperature rock engineering. 展开更多
关键词 GRANITE Thermal shock cycles Acoustic emission Thermal damage Failure precursor
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Life cycle environmental impacts and emission reduction pathways of wind power in western China:A scenario-based assessment
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作者 Ning Su Xiaobing Li +3 位作者 Xin Lyu Dongliang Dang Siyu Liu Chenhao Zhang 《Geography and Sustainability》 2026年第1期54-65,共12页
Compared with traditional energy sources,wind power has a lower environmental impact.However,emissions are still generated across the life cycle of wind turbines,from production to recycling.As wind power rapidly deve... Compared with traditional energy sources,wind power has a lower environmental impact.However,emissions are still generated across the life cycle of wind turbines,from production to recycling.As wind power rapidly develops and deployment increases,these impacts are becoming increasingly evident.A comprehensive understanding of these impacts is crucial for sustainable development.Based on the harmonization of previous detailed life cycle assessment(LCA)studies,this study develops a simplified LCA model that estimates the life cycle environmental impacts of wind turbines based on their nominal power.Using this simplified LCA model,we assess the global warming potential(GWP),acidification potential(AP),and cumulative energy demand(CED)of wind power at the regional scale for 2022 and under three future scenarios(high-power wind turbine promotion,reduced wind curtailment,and a comprehensive development scenario).The results indicate that in 2022,the life cycle GWP,AP,and CED of wind power in western China were 10.76 g CO_(2) eq/kWh,0.177 g SO_(2) eq/kWh,and 17.6 kJ/kWh,respectively.Scenario simulations suggest that reducing wind curtailment is the most effective approach for reducing emissions in Inner Mongolia,Gansu,Qinghai,Ningxia,and Xinjiang,producing average decreases of 8.64%in GWP,8.39%in AP,and 9.26%in CED.In contrast,for Guangxi,Chongqing,Sichuan,Guizhou,Yunnan,Xizang,and Shaanxi,the promotion of high-power wind turbines provides greater environmental benefits than reducing curtailment,producing average decreases of 3.45%,3.09%,and 4.29%in GWP,AP,and CED,respectively.These findings help clarify the environmental impact of wind power across its life cycle at the regional scale and provide theoretical references for the direction of future wind power development and the formulation of related policies. 展开更多
关键词 Wind energy Life cycle assessment Environmental impact Scenario simulation Western China
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The extract of Cyperus rotundus rhizome promotes hair growth and modulates hair cycle in vivo and in vitro
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作者 Yunwei Hu Keke Hu +4 位作者 Jiaying Liang Xingjiang Zhang Huijuan Li Jianxin Wu Qing Huang 《Chinese Journal of Natural Medicines》 2026年第2期203-214,共12页
Hair loss,a multifactorial disorder characterized by follicular miniaturization and excessive shedding,significantly impairs psychological well-being and quality of life.Cyperus rotundus rhizome(CR),a traditional Chin... Hair loss,a multifactorial disorder characterized by follicular miniaturization and excessive shedding,significantly impairs psychological well-being and quality of life.Cyperus rotundus rhizome(CR),a traditional Chinese medicine used for various ailments,has not been evaluated for efficacy in treating hair loss.This study presents the first comprehensive assessment of the hair growth-promoting effects of ethanol extract from CR on mouse primary dermal papilla cells(MDPCs)and human immortalized hair DPCs(IHHDPCs),employing cell counting kit-8(CCK-8),scratch assay,reverse transcription-quantitative polymerase chain reaction(RT-q PCR),and Western blot(WB).CR treatment activated the Wnt/β-Catenin signaling pathway by upregulating Wnt10b,increasingβ-Catenin protein levels and promoting its nuclear translocation,while simultaneously downregulating transforming growth factor-beta 1(TGF-β1),BMP4,and dickkopf-related protein 1(DKK1)in MDPCs.These molecular changes enhanced cell proliferation and increased secretion of key growth factors—insulin-like growth factor 1(IGF1),keratinocyte growth factor(KGF),and vascular endothelial growth factor(VEGF)—thereby stimulating hair growth and prolonging the anagen phase,which was confirmed in an ex vivo hair follicle(HF)organ culture model.Chromatographic analysis identified the petroleum ether fraction(CRP),enriched in sesquiterpenes,as the primary bioactive component.Both CR and CRP promoted IHHDPC proliferation,migration,and growth factor expression through activation of the Wnt/β-Catenin pathway,with CRP exhibiting superior bioactivity.Furthermore,both treatments stimulated HF cycling,increased follicular density,and upregulated Ki67 andβ-Catenin expression in the dorsal skin of C57BL/6 mice.Collectively,these findings demonstrate that CR and CRP promote hair growth and modulate the hair cycle via enhancement of Wnt/β-Catenin signaling,providing a scientific basis for the potential clinical application of C.rotundus rhizomes in hair loss therapy and the development of related pharmaceuticals or cosmetics. 展开更多
关键词 Cyperus rotundus Hair growth Hair cycle WNT/Β-CATENIN
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Mechanistic study of oxide participation in the C^(∗) cycle catalysis over Fe_(5)C_(2)
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作者 Fugui He Xiangbin Kong +6 位作者 Tong Zhang Bing Zheng Kuan Lu Jianli Zhang Tiansheng Zhao Xinhua Gao Yurong He 《Chinese Journal of Chemical Engineering》 2026年第1期208-219,共12页
The conversion of CO_(2) into high value added chemicals via the Fischer-Tropsch synthesis(FTS)reaction has attracted significant attention.The surface oxygenation environment is a significant factor influencing the p... The conversion of CO_(2) into high value added chemicals via the Fischer-Tropsch synthesis(FTS)reaction has attracted significant attention.The surface oxygenation environment is a significant factor influencing the performance of the catalyst.In this work,spin-polarized density-functional theory calculations have been used to investigate the adsorption and reactions of CO_(2) and H to generate CH4 and CH3OH on Fe_(5)C_(2)(100)surfaces with varying OH∗coverage.On the pure Fe_(5)C_(2)(100)surface,surface C^(∗) preferentially reacts with hydrogen to form CH4,exposing C^(∗) vacancy.CO_(2) favors adsorbing on the C^(∗) vacancy to further dissociating and activating.The co-adsorption of OH∗promotes the C^(∗) cycle process by facilitating the hydrogenation of C^(∗).The Fe_(5)C_(2) surface with an oxide interface is favorable for reducing FexOy,thereby maintaining the dynamic stability of the surface.Therefore,surface oxidation is inevitably involved in the entire C^(∗) cycle of the FTS reaction and regulates the relative content of iron oxides and iron carbides.Our work can contribute to the rational modulation of the surface C^(∗) cycle,thereby enhancing catalyst performance. 展开更多
关键词 C^(∗)cycle Iron-based catalyst CO_(2)hydrogenation Fischer-Tropsch synthesis(FTS) Surface oxidation
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Oxygen-Pressure Protocol Breaking Cycle Limit of Continuously Reversible Lithium-Oxygen Batteries
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作者 Xinhang Cui Fenglong Xiao +10 位作者 Guoliang Zhang Zhangliu Tian Qingshan Bao Yanlu Li Deliang Cui Qilong Wang Feng Dang Wei Chen Haohai Yu Huaijin Zhang Gang Lian 《Nano-Micro Letters》 2026年第5期391-404,共14页
Lithium-oxygen(Li-O_(2))battery is favored among“beyond lithiumion”technologies for sustainability because of its exceptional energy density.Major impediments are the poor cycle stability and grievous capacity degra... Lithium-oxygen(Li-O_(2))battery is favored among“beyond lithiumion”technologies for sustainability because of its exceptional energy density.Major impediments are the poor cycle stability and grievous capacity degradation at high current densities.We address these issues by a“killing two birds with one stone”O_(2)-pressure protocol.It first resolves efficient O_(2) mass transport at high rates..The accelerated reaction kinetics optimizes the composition and growth pathway of discharge products.This protocol secondly achieves protection of Li anodes via densifying corrosion layers on them.Consequently,the battery delivers both ultrahigh discharge capacity(>9,000 mAh g^(-1))at 3,000 mA g^(-1) and excellent cycling stability.Under a dual-strategy effect of high-pressure O_(2) and artificial protection layers,the battery actualizes over 11-fold increase in cycle life of 5,170 h(2,585 cycles).The strategy opens avenues for advancing Li-O_(2) batteries towards practical application and confers the extension to other gas-based batteries. 展开更多
关键词 Li-O_(2)batteries O_(2)pressure cycle life Li anode protection Rate performance
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Study on the strength deterioration characteristics and microscopic mechanisms of moraine soil under freeze-thaw cycles
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作者 Peng-fei Wang Ming-li Li +3 位作者 Ming Chang Jun-lin Jiang Fan Yang Zhi-qiang Zuo 《Journal of Groundwater Science and Engineering》 2026年第1期15-31,共17页
To investigate the strength degradation characteristics and microscopic damage mechanisms of moraine soil under hydro-thermo-mechanical coupling conditions,a series of X-ray Diffraction(XRD),standard triaxial testing,... To investigate the strength degradation characteristics and microscopic damage mechanisms of moraine soil under hydro-thermo-mechanical coupling conditions,a series of X-ray Diffraction(XRD),standard triaxial testing,Scanning Electron Microscopy(SEM),and Nuclear Magnetic Resonance(NMR)experiments were conducted.The mechanical property degradation laws and evolution characteristics of the microscopic pore structure of moraine soil under Freeze-Thaw(F-T)conditions were revealed.After F-T cycles,the stress-strain curves of moraine soil showed a strain-softening trend.In the early stage of F-T cycles(0–5 cycles),the shear strength and elastic modulus exhibited damage rate of approximately 10.33%±0.8%and 16.60%±1.2%,respectively.In the later stage(10–20 cycles),the strength parameters fluctuated slightly and tended to stabilize.The number of F-T cycles was negatively exponentially correlated with cohesion,while showing only slight fluctuation in the internal friction angle,thereby extending the Mohr-Coulomb strength criterion for moraine soil under F-T cycles.The NMR experiments quantitatively characterized the evolution of the internal pore structure of moraine soil under F-T cycles.As the number of F-T cycles increased,fine and micro pores gradually expanded and merged due to the frost-heaving effect during the water-ice phase transition,forming larger pores.The proportion of large and medium pores increased to 59.55%±2.1%(N=20),while that of fine and micro pores decreased to 40.45%±2.1%(N=20).The evolution of pore structure characteristics was essentially completed in the later stage of F-T cycles(10–20 cycles).This study provides a theoretical foundation and technical support for major engineering construction and disaster prevention in the Qinghai-Xizang Plateau. 展开更多
关键词 Moraine soil in the Qinghai-Xizang Plateau F-T cycle Standard triaxial tests soil strength degradation Mohr-Coulomb criterion Microscopic pore structure
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Artificial Cycle with or without a Depot Gonadotropin-releasing Hormone Agonist for Frozen-thawed Embryo Transfer: An Assessment of Infertility Type that Is Most Suitable 被引量:6
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作者 Di XIE Fan CHEN +4 位作者 Shou-zhen XIE Zhi-lan CHEN Ping TUO Rong ZHOU Juan ZHANG 《Current Medical Science》 SCIE CAS 2018年第4期626-631,共6页
The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone (GnRH) a... The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone (GnRH) agonist were assessed. A retrospective cohort analysis was performed on 1003 cycles undergoing frozen-thawed, cleavage-stage embryo transfers from January 1, 2012 to June 31, 2015 in the Reproductive Medicine Center of Wuhan General Hospital of Guangzhou Military Region. Based on the infertility etiologies of the patients, the 1003 cycles were divided into five groups: tubal infertility, polycystic ovary syndrome (PCOS), endometriosis, male infertility, and unexplained infertility. The main outcome was the live birth rate. Two groups were set up based on the intervention: group A was given a GnRH agonist with exogenous estrogen and progesterone, and group B (control group) was given exogenous estrogen and progesterone only. The results showed that the baseline serum hormone levels and basic characteristics of the patients were not significantly different between groups A and B. The live birth rates in groups A and B were 41.67% and 29.29%, respectively (P〈0.05). The live birth rates in patients with PCOS in groups A and B were 56.25% and 30.61%, respectively (P〈0.05). The clinical pregnancy, implantation and on-going pregnancy rates showed the same trends as the live birth rates between groups A and B. The ectopic pregnancy rate was significantly lower in group A than in group B. We concluded that the live birth rate was higher and other clinical outcomes were more satisfactory with GnRH agonist co- treatment than without GnRH agonist co-treatment for frozen-thawed embryo transfer. The GnRH agonist combined with exogenous estrogen and progesterone worked for all types of infertility tested, especially for women with PCOS. 展开更多
关键词 frozen-thawed embryo transfer gonadotropin-releasing hormone agonist polycystic ovary syndrome
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Embryo Transfer Strategies for Women with Recurrent Implantation Failure During the Frozen-thawed Embryo Transfer Cycles:Sequential Embryo Transfer or Double-blastocyst Transfer?
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作者 Qiao-hang ZHAO Yu-wei SONG +8 位作者 Jian CHEN Xiang ZHOU Ji-lai XIE Qiu-ping YAO Qi-yin DONG Chun FENG Li-ming ZHOU Wei-ping FU Min JIN 《Current Medical Science》 SCIE CAS 2024年第1期212-222,共11页
Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of Se... Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of SeET and DBT on pregnancy outcomes.Methods Totally,261 frozen-thawed embryo transfer cycles of 243 RIF women were included in this multicenter retrospective analysis.According to different embryo quality and transfer strategies,they were divided into four groups:group A,good-quality SeET(GQ-SeET,n=38 cycles);group B,poor-quality or mixed-quality SeET(PQ/MQ-SeET,n=31 cycles);group C,good-quality DBT(GQ-DBT,n=121 cycles);and group D,poor-quality or mixed-quality DBT(PQ/MQ-DBT,n=71 cycles).The main outcome,clinical pregnancy rate,was compared,and the generalized estimating equation(GEE)model was used to correct potential confounders that might impact pregnancy outcomes.Results GQ-DBT achieved a significantly higher clinical pregnancy rate(aOR 2.588,95%CI 1.267–5.284,P=0.009)and live birth rate(aOR 3.082,95%CI 1.482–6.412,P=0.003)than PQ/MQ-DBT.Similarly,the clinical pregnancy rate was significantly higher in GQ-SeET than in PQ/MQ-SeET(aOR 4.047,95%CI 1.218–13.450,P=0.023).The pregnancy outcomes of GQ-SeET were not significantly different from those of GQ-DBT,and the same results were found between PQ/MQ-SeET and PQ/MQ-DBT.Conclusion SeET relative to DBT did not seem to improve pregnancy outcomes for RIF patients if the embryo quality was comparable between the two groups.Better clinical pregnancy outcomes could be obtained by transferring good-quality embryos,no matter whether in SeET or DBT.Embryo quality plays a more important role in pregnancy outcomes for RIF patients. 展开更多
关键词 recurrent implantation failure sequential embryo transfer frozen-thawed embryo transfer embryo transfer strategies
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Serum β-hCG level on day 7 of frozen-thawed embryo transfer: association with the clinical pregnancy outcomes in artificial cycles
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作者 Na Sun Shu-Yi Dong +1 位作者 Ping-Ping Sun Hua-Gang Ma 《Clinical Research Communications》 2022年第3期29-33,共5页
Objective:The relationship between serum beta human chorionic gonadotropin(β-hCG)levels of patients(7 days after the transplantation of frozen-thawed embryos)and the pregnancy outcomes was investigated.Methods:This s... Objective:The relationship between serum beta human chorionic gonadotropin(β-hCG)levels of patients(7 days after the transplantation of frozen-thawed embryos)and the pregnancy outcomes was investigated.Methods:This study was designed as a retrospective clinical trial of 366 women who underwent frozen-thawed embryo transfers(FETs)in artificial cycles.Patients were divided into three groups:clinical pregnancy group,biochemical pregnancy group,and non-pregnant group according to their pregnancy outcomes.Serumβ-hCG levels were tested on day 4,7,9,11 and 14 after FET.Results:In the clinical pregnancy group,the serumβ-hCG levels after 7-day post-transplantation were significantly elevated(16.20 IU/L vs.3.07 vs.0.1 IU/L;P<0.05)compared with the other two groups.Furthermore,it was found that Area Under Curve(AUC=0.96)was significant with cut-off value higher than 4.26 IU/L(sensitivity=92.3%,specificity=90.2%)to predict the clinical pregnancy outcomes in the receiver operating characteristic(ROC)analysis ofβ-hCG concentrations on day 7 of post-transplantation.Conclusion:Our results suggested that the elevated serumβ-hCG levels on day 7 of post-transplantation could predict the positive clinical pregnancy outcomes in artificial FET cycles. 展开更多
关键词 frozen-thawed embryo transfer pregnancy outcomes artificial cycle human chorionic gonadotrophin INFERTILITY
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Comparison of clinical outcomes of frozen-thawed blastocysts transfer in natural and hormonally controlled cycles
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作者 高辉 孙正怡 +2 位作者 邓成艳 郁琦 何方方 《生殖医学杂志》 CAS 2007年第A01期79-83,共5页
Objectives:To assess the clinical outcomes of frozen-thawed blastocysts transfer in natural and hormonally controlled cycles.Methods:A retrospective analysis of natural and hormonally controlled cycle for 246 frozen-t... Objectives:To assess the clinical outcomes of frozen-thawed blastocysts transfer in natural and hormonally controlled cycles.Methods:A retrospective analysis of natural and hormonally controlled cycle for 246 frozen-thawed blastocyst transfer cycles,the clinical pregnancy rate,implantation rate,early abortion rate were compared.Results:Of the 192 hormonally controlled cycles,the cancel rate,clinical pregnancy rate per ET,implantation rate and abortion rate were 7.3%(14/192),53.9%(96/178),38.8%(131/338)and 11.5%(11/96)respectively,whereas in 54 natural cycles,these rates were 16.7%(9/54),68.9%(31/45),52.9%(45/85)and 16.1%(5/31)respectively.There was no significant difference between the two groups with regard to the clinical pregnancy and abortion rate per ET,but the cancel rate and implantation rate were higher in natural cycles.However,the pregnancy and implantation rates of patients without PCOS in hormonal control cycles(57.2%,40.9%)were similar with those in natural cycles(P>0.05).Conclusion:These findings suggested that both hormonally controlled and natural cycles had similar pregnancy outcomes in frozen-thawed blastocysts transfer. 展开更多
关键词 胚泡 临床分析 生殖功能 孕妇
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基于改进CycleGAN的小样本玉米病害图像扩充方法
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作者 李艳玲 张博翔 +3 位作者 李飞涛 Bacao Fernando 司海平 陈丽娜 《华中农业大学学报》 北大核心 2025年第5期198-207,共10页
针对玉米病害图像识别任务存在数据集获取困难、样本不足及不同类别病害样本不均衡等问题,设计一种基于改进CycleGAN(cycle-consistent adversarial networks)的图像数据增强方法。首先,使用较小感受野的卷积核优化CycleGAN网络结构,生... 针对玉米病害图像识别任务存在数据集获取困难、样本不足及不同类别病害样本不均衡等问题,设计一种基于改进CycleGAN(cycle-consistent adversarial networks)的图像数据增强方法。首先,使用较小感受野的卷积核优化CycleGAN网络结构,生成高质量样本图像,减少过拟合现象发生;其次,将SE(squeeze-excitation)注意力机制嵌入到生成器的残差模块中,增强CycleGAN对病害特征的提取能力,使网络更准确地捕捉小目标病害或域间差异不明显的特征。结果显示,改进后的CycleGAN相较于原始CycleGAN、DCGAN、DCGAN+和WGAN算法,生成病害图像的FID分数分别降低了43.33、32.67、24.24和19.72,GAN-train与GANtest相较于原始CycleGAN提升了3.13、4.25百分点;采用改进的CycleGAN图像扩充方法构建玉米病害数据集,基于该数据集的玉米叶片病害识别模型准确率在3种网络架构上均得到有效提升:AlexNet提升3.90百分点,VGGNet提升4.41百分点,ResNet提升3.44百分点,在ResNet网络架构上与传统数据增强算法相比病害识别率提升5.79百分点。结果表明,改进的CycleGAN网络有效解决了玉米病害图像数据集匮乏的问题。 展开更多
关键词 数据增强 玉米叶片病害 残差模块 循环一致性生成对抗网络
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基于改进CycleGAN的非配对CMR图像增强
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作者 郑伟 吴禹波 +2 位作者 冯晓萌 马泽鹏 宋铁锐 《河北大学学报(自然科学版)》 北大核心 2025年第2期204-215,共12页
心脏磁共振成像(cardiac magnetic resonance,CMR)过程中患者误动、异常幅度的呼吸运动、心律失常会造成CMR图像质量下降,为解决现有的CMR图像增强网络需要人为制作配对数据,且图像增强后部分组织纹理细节丢失的问题,提出了基于空频域... 心脏磁共振成像(cardiac magnetic resonance,CMR)过程中患者误动、异常幅度的呼吸运动、心律失常会造成CMR图像质量下降,为解决现有的CMR图像增强网络需要人为制作配对数据,且图像增强后部分组织纹理细节丢失的问题,提出了基于空频域特征学习的循环一致性生成对抗网络(cycle-consistent generative adversavial network based on spatial-frequency domain feature learning,SFFL-CycleGAN).研究结果表明,该网络无须人为制作配对数据集,增强后的CMR图像组织纹理细节丰富,在结构相似度(structural similarity,SSIM)和峰值信噪比(peak signal to noise ratio,PSNR)等方面均优于现有的配对训练网络以及原始的CycleGAN网络,图像增强效果好,有效助力病情诊断. 展开更多
关键词 心脏磁共振成像 图像增强 空频域特征 循环一致性生成对抗网络
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鸭瘟病毒Cycleave荧光PCR检测方法的建立
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作者 于新友 李天芝 苗立中 《中国动物传染病学报》 北大核心 2025年第2期106-110,共5页
为建立一种敏感、快速和特异的鸭瘟病毒(DPV)检测方法,本研究根据NCBI收录的DPV UL6基因序列,设计了1对特异性引物和1条Cycling探针,通过优化反应条件,建立了检测DPV的Cycleave荧光PCR检测方法。结果显示:该方法特异性高,不与其他常见... 为建立一种敏感、快速和特异的鸭瘟病毒(DPV)检测方法,本研究根据NCBI收录的DPV UL6基因序列,设计了1对特异性引物和1条Cycling探针,通过优化反应条件,建立了检测DPV的Cycleave荧光PCR检测方法。结果显示:该方法特异性高,不与其他常见鸭病病原体发生交叉反应,检测DPV灵敏度可达6.5拷贝/μL,批内与批间的变异系数均小于2%。研究表明,建立的DPV Cycleave荧光定量PCR方法特异性高、敏感性高、重复性好,可用于临床样品检测,为鸭瘟的诊断和防控奠定了基础。 展开更多
关键词 鸭瘟病毒 cycling探针 cycleave荧光PCR 检测
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改进CycleGAN的半监督建筑物提取算法
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作者 卢鹏 仲闯 《计算机工程》 北大核心 2025年第3期241-251,共11页
建筑物提取需要大量的标注数据进行训练,收集和标注数据需要耗费大量时间。为了在小样本遥感图像数据集上基于半监督学习实现建筑物提取的目的,构建4组建筑物提取数据集,提出了一种基于循环一致性生成对抗网络(CycleGAN)的建筑物提取算... 建筑物提取需要大量的标注数据进行训练,收集和标注数据需要耗费大量时间。为了在小样本遥感图像数据集上基于半监督学习实现建筑物提取的目的,构建4组建筑物提取数据集,提出了一种基于循环一致性生成对抗网络(CycleGAN)的建筑物提取算法。首先,在生成器中引入全局注意力机制(GAM)以增强对建筑物和图像背景细节特征的区分;其次,在判别器中加入谱归一化层以增强训练稳定性,解决了训练过程中梯度消失问题;最后,改进对抗损失和循环一致性损失以提高生成图像的质量,避免生成图像的过度平滑化,并引入Identity损失以限制生成器不会自主修改输入图像的颜色,保证输入图像与输出图像颜色组成的一致性。实验结果表明,在第1组小样本数据集上,与UNIT、MUNIT、U-GAT-IT、SPatchGAN、QS-Attn模型进行半监督实验对比,结构相似性(SSIM)值和准确率分别至少提高了3、8.1百分点,在扩充数据规模的数据集上,使用改进后的算法进行全监督和半监督实验对比,验证了改进后的算法在小样本遥感图像数据集上实现建筑物半监督提取的有效性。 展开更多
关键词 建筑物提取 循环一致性生成对抗网络 谱归一化 全局注意力机制 半监督
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