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Purposeless repeated acquisition time-lapse seismic data processing 被引量:3
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作者 Li Jingye Chen Xiaohong +1 位作者 Zhao Wei Zhang Yunpeng 《Petroleum Science》 SCIE CAS CSCD 2008年第1期31-36,共6页
In China, most oil fields are continental sedimentation with strong heterogeneity, which on one side makes the reservoir prospecting and development more difficult, but on the other side provides more space for search... In China, most oil fields are continental sedimentation with strong heterogeneity, which on one side makes the reservoir prospecting and development more difficult, but on the other side provides more space for searching residual oil in matured fields. Time-lapse seismic reservoir monitoring technique is one of most important techniques to define residual oil distribution. According to the demand for and development of time-lapse seismic reservoir monitoring in China, purposeless repeated acquisition time-lapse seismic data processing was studied. The four key steps in purposeless repeated acquisition time-lapse seismic data processing, including amplitude-preserved processing with relative consistency, rebinning, match filtering and difference calculation, were analyzed by combining theory and real seismic data processing. Meanwhile, quality control during real time-lapse seismic processing was emphasized. 展开更多
关键词 time-lapse seismic purposeless repeated acquisition rebinning match filtering amplitude-preserved processing
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The AVO Effect of Formation Pressure on Time-Lapse Seismic Monitoring in Marine Carbon Dioxide Storage
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作者 Fan Wu Qingping Li +1 位作者 Yufa He Jingye Li 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期645-655,共11页
The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the informatio... The phase change of CO_(2) has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO_(2) is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO_(2) saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO_(2) storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers(or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO_(2) injection is calculated. And so are the effects of porosity and CO_(2) saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO_(2) saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO_(2) sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO_(2) reservoirs. 展开更多
关键词 time-lapse seismic monitoring Marine carbon dioxide storage AVO modeling Formation pressure Anisotropic Rockphysical model
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Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响
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作者 蔡冰红 谢晓俊 《智慧健康》 2024年第11期42-44,共3页
目的探讨Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响。方法选取2021年3月—2023年3月在本院生殖中心行IVF-ET/ICSI-ET治疗的613个周期的胚胎发育数据,随机分配胚胎培养方式。分为对照组与研究组,其中对照组为桌面台式培... 目的探讨Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响。方法选取2021年3月—2023年3月在本院生殖中心行IVF-ET/ICSI-ET治疗的613个周期的胚胎发育数据,随机分配胚胎培养方式。分为对照组与研究组,其中对照组为桌面台式培养箱方式(360个周期),研究组为Time-lapse培养与桌面台式培养箱方式(253个周期),统计两组胚胎发育质量。结果研究组中正常受精数、可移植胚胎数、形成囊胚数、优质胚胎数、高评分囊胚数、受精率、冷冻胚胎率、胚囊形成率、优质胚胎率、高评分囊胚率高于对照组,组间差异有统计学意义(P<0.05)。结论Time-lapse培养与桌面台式培养箱胚胎培养方式优于桌面台式培养箱方式,可为胚胎培养提供适宜的环境、温度、湿度等,有助于胚胎发育,具有较强的实用性和推广性,值得推广应用。 展开更多
关键词 time-lapse培养 桌面台式培养箱 胚胎培养 胚胎发育
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A novel method for clustering cellular data to improve classification
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作者 Diek W.Wheeler Giorgio A.Ascoli 《Neural Regeneration Research》 SCIE CAS 2025年第9期2697-2705,共9页
Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subse... Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are missing.We recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within clusters.Here we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical testing.These general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical datasets.We demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons. 展开更多
关键词 cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering
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A New Encryption Mechanism Supporting the Update of Encrypted Data for Secure and Efficient Collaboration in the Cloud Environment
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作者 Chanhyeong Cho Byeori Kim +1 位作者 Haehyun Cho Taek-Young Youn 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期813-834,共22页
With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud... With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly increased.However,traditional collaboration tools primarily rely on access control,leaving data stored on cloud servers vulnerable due to insufficient encryption.This paper introduces a novel mechanism that encrypts data in‘bundle’units,designed to meet the dual requirements of efficiency and security for frequently updated collaborative data.Each bundle includes updated information,allowing only the updated portions to be reencrypted when changes occur.The encryption method proposed in this paper addresses the inefficiencies of traditional encryption modes,such as Cipher Block Chaining(CBC)and Counter(CTR),which require decrypting and re-encrypting the entire dataset whenever updates occur.The proposed method leverages update-specific information embedded within data bundles and metadata that maps the relationship between these bundles and the plaintext data.By utilizing this information,the method accurately identifies the modified portions and applies algorithms to selectively re-encrypt only those sections.This approach significantly enhances the efficiency of data updates while maintaining high performance,particularly in large-scale data environments.To validate this approach,we conducted experiments measuring execution time as both the size of the modified data and the total dataset size varied.Results show that the proposed method significantly outperforms CBC and CTR modes in execution speed,with greater performance gains as data size increases.Additionally,our security evaluation confirms that this method provides robust protection against both passive and active attacks. 展开更多
关键词 Cloud collaboration mode of operation data update efficiency
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Impact of ocean data assimilation on the seasonal forecast of the 2014/15 marine heatwave in the Northeast Pacific Ocean
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作者 Tiantian Tang Jiaying He +1 位作者 Huihang Sun Jingjia Luo 《Atmospheric and Oceanic Science Letters》 2025年第1期24-31,共8页
A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 m.This study em... A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 m.This study employed two assimilation schemes based on the global Climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine heatwave.The sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep ocean.The latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging scheme.It excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the Blob.These improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean conditions.The results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms. 展开更多
关键词 Seasonal forecast Ocean data assimilation Marine heatwave Subsurface temperature
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Synthetic data as an investigative tool in hypertension and renal diseases research
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作者 Aleena Jamal Som Singh Fawad Qureshi 《World Journal of Methodology》 2025年第1期9-13,共5页
There is a growing body of clinical research on the utility of synthetic data derivatives,an emerging research tool in medicine.In nephrology,clinicians can use machine learning and artificial intelligence as powerful... There is a growing body of clinical research on the utility of synthetic data derivatives,an emerging research tool in medicine.In nephrology,clinicians can use machine learning and artificial intelligence as powerful aids in their clinical decision-making while also preserving patient privacy.This is especially important given the epidemiology of chronic kidney disease,renal oncology,and hypertension worldwide.However,there remains a need to create a framework for guidance regarding how to better utilize synthetic data as a practical application in this research. 展开更多
关键词 Synthetic data Artificial intelligence NEPHROLOGY Blood pressure RESEARCH EDITORIAL
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Evaluation of ERA5 reanalysis temperature data over the Qilian Mountains of China
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作者 ZHAO Peng HE Zhibin 《Journal of Mountain Science》 2025年第1期198-209,共12页
Air temperature is an important indicator to analyze climate change in mountainous areas.ERA5 reanalysis air temperature data are important products that were widely used to analyze temperature change in mountainous a... Air temperature is an important indicator to analyze climate change in mountainous areas.ERA5 reanalysis air temperature data are important products that were widely used to analyze temperature change in mountainous areas.However,the reliability of ERA5 reanalysis air temperature over the Qilian Mountains(QLM)is unclear.In this study,we evaluated the reliability of ERA5 monthly averaged reanalysis 2 m air temperature data using the observations at 17 meteorological stations in the QLM from 1979 to 2017.The results showed that:ERA5 reanalysis monthly averaged air temperature data have a good applicability in the QLM in general(R2=0.99).ERA5 reanalysis temperature data overestimated the observed temperature in the QLM in general.Root mean square error(RMSE)increases with the increasing of elevation range,showing that the reliability of ERA5 reanalysis temperature data is worse in higher elevation than that in lower altitude.ERA5 reanalysis temperature can capture observational warming rates well.All the smallest warming rates of observational temperature and ERA5 reanalysis temperature are found in winter,with the warming rates of 0.393°C/10a and 0.360°C/10a,respectively.This study will provide a reference for the application of ERA5 reanalysis monthly averaged air temperature data at different elevation ranges in the Qilian Mountains. 展开更多
关键词 ERA5 Reanalysis data Air temperature Qilian Mountains Climate change
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Topology Data Analysis-Based Error Detection for Semantic Image Transmission with Incremental Knowledge-Based HARQ
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作者 Ni Fei Li Rongpeng +1 位作者 Zhao Zhifeng Zhang Honggang 《China Communications》 2025年第1期235-255,共21页
Semantic communication(SemCom)aims to achieve high-fidelity information delivery under low communication consumption by only guaranteeing semantic accuracy.Nevertheless,semantic communication still suffers from unexpe... Semantic communication(SemCom)aims to achieve high-fidelity information delivery under low communication consumption by only guaranteeing semantic accuracy.Nevertheless,semantic communication still suffers from unexpected channel volatility and thus developing a re-transmission mechanism(e.g.,hybrid automatic repeat request[HARQ])becomes indispensable.In that regard,instead of discarding previously transmitted information,the incremental knowledge-based HARQ(IK-HARQ)is deemed as a more effective mechanism that could sufficiently utilize the information semantics.However,considering the possible existence of semantic ambiguity in image transmission,a simple bit-level cyclic redundancy check(CRC)might compromise the performance of IK-HARQ.Therefore,there emerges a strong incentive to revolutionize the CRC mechanism,thus more effectively reaping the benefits of both SemCom and HARQ.In this paper,built on top of swin transformer-based joint source-channel coding(JSCC)and IK-HARQ,we propose a semantic image transmission framework SC-TDA-HARQ.In particular,different from the conventional CRC,we introduce a topological data analysis(TDA)-based error detection method,which capably digs out the inner topological and geometric information of images,to capture semantic information and determine the necessity for re-transmission.Extensive numerical results validate the effectiveness and efficiency of the proposed SC-TDA-HARQ framework,especially under the limited bandwidth condition,and manifest the superiority of TDA-based error detection method in image transmission. 展开更多
关键词 error detection incremental knowledgebased HARQ joint source-channel coding semantic communication swin transformer topological data analysis
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Data driven prediction of fragment velocity distribution under explosive loading conditions
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作者 Donghwan Noh Piemaan Fazily +4 位作者 Songwon Seo Jaekun Lee Seungjae Seo Hoon Huh Jeong Whan Yoon 《Defence Technology(防务技术)》 2025年第1期109-119,共11页
This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key de... This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key design parameters including casing dimensions and detonation positions.The paper details the finite element analysis for fragmentation,the characterizations of the dynamic hardening and fracture models,the generation of comprehensive datasets,and the training of the ANN model.The results show the influence of casing dimensions on fragment velocity distributions,with the tendencies indicating increased resultant velocity with reduced thickness,increased length and diameter.The model's predictive capability is demonstrated through the accurate predictions for both training and testing datasets,showing its potential for the real-time prediction of fragmentation performance. 展开更多
关键词 data driven prediction Dynamic fracture model Dynamic hardening model FRAGMENTATION Fragment velocity distribution High strain rate Machine learning
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Landslide monitoring in southwestern China via time-lapse electrical resistivity tomography 被引量:13
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作者 徐冬 胡祥云 +1 位作者 单春玲 李睿恒 《Applied Geophysics》 SCIE CSCD 2016年第1期1-12,217,共13页
The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability,rainwater infiltration,and subsurface hydrogeology.However,the understanding of this complicated cor... The dynamic monitoring of landslides in engineering geology has focused on the correlation among landslide stability,rainwater infiltration,and subsurface hydrogeology.However,the understanding of this complicated correlation is still poor and inadequate.Thus,in this study,we investigated a typical landslide in southwestern China via time-lapse electrical resistivity tomography(TLERT) in November 2013 and August 2014.We studied landslide mechanisms based on the spatiotemporal characteristics of surface water infiltration and flow within the landslide body.Combined with borehole data,inverted resistivity models accurately defined the interface between Quaternary sediments and bedrock.Preferential flow pathways attributed to fracture zones and fissures were also delineated.In addition,we found that surface water permeates through these pathways into the slipping mass and drains away as fissure water in the fractured bedrock,probably causing the weakly weathered layer to gradually soften and erode,eventually leading to a landslide.Clearly,TLERT dynamic monitoring can provide precursory information of critical sliding and can be used in landslide stability analysis and prediction. 展开更多
关键词 time-lapse electrical resistivity tomography LANDSLIDE HYDROGEOPHYSICS MONITORING preferential flow
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使用time-lapse筛选早期IVF/ICSI胚胎及其临床结局 被引量:4
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作者 陈明颢 黄军 +1 位作者 钟影 全松 《南方医科大学学报》 CAS CSCD 北大核心 2015年第12期1760-1764,1781,共6页
目的通过比较使用time-lapse(延迟摄像)和传统形态学方法筛选IVF/ICSI胚胎的临床结局,评价time-lapse用于早期胚胎观察和筛选的价值。方法回顾性分析139个IVF/ICSI周期的资料,根据胚胎的筛选方法,分为time-lapse monitoring组(TLM组... 目的通过比较使用time-lapse(延迟摄像)和传统形态学方法筛选IVF/ICSI胚胎的临床结局,评价time-lapse用于早期胚胎观察和筛选的价值。方法回顾性分析139个IVF/ICSI周期的资料,根据胚胎的筛选方法,分为time-lapse monitoring组(TLM组)(n=68)和对照组(n=71),比较两组间的βHCG阳性率、临床妊娠率和胚胎着床率,并根据女方年龄、受精方式进行亚组分析。结果 TLM组的βHCG阳性率、临床妊娠率、胚胎着床率分别为:66.2%、61.8%、47.1%;对照组的βHCG阳性率、临床妊娠率、胚胎着床率分别为:47.9%、43.7%、30.3%;TLM组的βHCG阳性率、临床妊娠率、胚胎着床率均高于对照组,且差异均有统计学意义(P〈0.05)。亚组分析显示:相较于年龄≤30岁的患者,年龄31~35岁的患者利用time-lapse更能明显改善临床结局;利用time-lapse能明显提高IVF周期的βHCG阳性率、临床妊娠率、胚胎着床率,但对于ICSI和TESA周期,效果则不理想。结论使用time-lapse动态监测胚胎并根据胚胎的形态动力学参数对胚胎进行评价和筛选,与传统方法相比,能获得更好的临床结局;年龄较大的(〉30岁)或者是进行IVF周期的患者更能从中获益。 展开更多
关键词 time-lapse 传统形态学方法 胚胎筛选 临床妊娠率 胚胎着床率
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利用Time-lapse技术筛选早期胚胎对IVF-ET妊娠结局的影响 被引量:2
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作者 丁洁 孟庆霞 +5 位作者 郑爱燕 蒲艳 廖桂芝 许咏乐 李红 王玮 《生殖医学杂志》 CAS 2019年第8期872-877,共6页
目的探索利用Time-lapse系统筛选早期胚胎的临床应用价值。方法回顾性分析本中心2016年7月至2017年12月,第一次新鲜或复苏周期D3卵裂期胚胎移植的患者资料,根据胚胎评估方法分为Time-lapse系统组(TLM组,n=74)和传统形态学评分组(CMA组,n... 目的探索利用Time-lapse系统筛选早期胚胎的临床应用价值。方法回顾性分析本中心2016年7月至2017年12月,第一次新鲜或复苏周期D3卵裂期胚胎移植的患者资料,根据胚胎评估方法分为Time-lapse系统组(TLM组,n=74)和传统形态学评分组(CMA组,n=951),比较这两种不同胚胎筛选方法对临床结局的影响。结果患者的不孕年限、体重指数、基础FSH、基础LH、E2、AMH、窦卵泡数、内膜厚度和周期类型等一般情况,在TLM组和CMA组均无显著差异(P均>0.05);TLM组年龄显著高于CMA组[(31.8±4.2)vs.(30.8±4.4),P<0.05],而平均移植胚胎数显著少于CMA组[(1.7±0.5)vs.(1.9±0.3),P<0.05];患者的临床结局,包括临床妊娠率、种植率、流产率、宫外孕率、双胎率和移植两个胚胎的双胎率等在两组间均无显著差异(P均>0.05)。进一步按照年龄分层分析,在<35岁患者,患者的一般情况在两组间均无显著差异(P均>0.05),TML组的平均移植胚胎数显著少于CMA组[(1.7±0.5)vs.(1.9±0.3),P<0.05],而患者临床结局在两组间亦无显著差异(P>0.05);在≥35岁患者,TML组的平均移植胚胎数显著少于CMA组[(1.7±0.5)vs.(1.9±0.4),P<0.05],而患者的一般情况和临床结局在两组间亦无显著差异(P>0.05)。结论利用Time-lapse技术选择早期胚胎,可以在显著减少移植胚胎数的基础上,维持稳定的临床妊娠结局。因此,认为Time-lapse技术可以在一定程度上优选出更具发育潜能的胚胎,为早期胚胎单胚胎移植提供新方法。 展开更多
关键词 time-lapse 早期胚胎 临床妊娠率 种植率
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Time-lapse是否能预测胚胎染色体整倍性? 被引量:2
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作者 黄国宁 《生殖医学杂志》 CAS 2019年第11期1249-1250,共2页
Time-lapse技术推进了胚胎评估的方法学,为胚胎评估带来了新的视角。Time-lapse系统理论上应具有预测胚胎染色体整倍性的潜力,但还需临床研究证实。
关键词 time-lapse系统 染色体整倍性
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应用time-lapse技术探讨7~10细胞D3优质胚胎的发育潜能 被引量:2
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作者 张京业 刘辉 +3 位作者 李梅 王苗苗 陶文荣 吴克良 《现代妇产科进展》 CSCD 北大核心 2016年第11期825-829,共5页
目的:探讨人体外受精-胚胎移植(IVF-ET)中第3天细胞数目为7、8、9、10优质胚胎的发育潜能。方法:选取2014年11月至2015年10月于山东大学附属生殖医院行IVF-ET患者的D3(授精后第三天)胚胎,利用time-lapse(延时摄像)技术分析7~10... 目的:探讨人体外受精-胚胎移植(IVF-ET)中第3天细胞数目为7、8、9、10优质胚胎的发育潜能。方法:选取2014年11月至2015年10月于山东大学附属生殖医院行IVF-ET患者的D3(授精后第三天)胚胎,利用time-lapse(延时摄像)技术分析7~10细胞优质胚胎的早期分裂行为,进而探讨胚胎早期分裂行为对囊胚形成率和临床结局的影响。结果:(1)四种细胞数胚胎早期的分裂行为不同:大多数8细胞胚胎为发育正常(NB)的胚胎;9细胞和10细胞中发生直接分裂(DC,一种异常分裂)的胚胎比例高于发育正常胚胎;所有7细胞胚胎均存在异常分裂,其中主要为逆分裂(RC,一种异常分裂)和同步分裂延迟(t8-t5,S3,胚胎由5细胞分裂为8细胞的时间)。(2)与NB相比,每一种异常分裂(DC,RC,S3)的发生均不同程度降低了胚胎的发育潜能。(3)四种细胞数胚胎的发育结局显示,8细胞胚胎有最高的囊胚形成率和胚胎着床率,其次为9细胞和10细胞胚胎,7细胞胚胎的囊胚形成率和着床率最低。结论:7、8、9、10四种细胞数胚胎早期发育过程中异常分裂的类型和所占比重不同,最终导致其发育潜能的差异。8细胞胚胎的发育潜能最高,其次为9细胞和10细胞胚胎,7细胞胚胎发育潜能最低。 展开更多
关键词 time-lapse 早期分裂行为 发育潜能
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Monitoring the change in horizontal stress with multi-wave time-lapse seismic response based on nonlinear elasticity theory 被引量:2
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作者 Fu-Bin Chen Zhao-Yun Zong Xing-Yao Yin 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期815-826,共12页
Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (... Monitoring the change in horizontal stress from the geophysical data is a tough challenge, and it has a crucial impact on broad practical scenarios which involve reservoir exploration and development, carbon dioxide (CO_(2)) injection and storage, shallow surface prospecting and deep-earth structure description. The change in in-situ stress induced by hydrocarbon production and localized tectonic movements causes the changes in rock mechanic properties (e.g. wave velocities, density and anisotropy) and further causes the changes in seismic amplitudes, phases and travel times. In this study, the nonlinear elasticity theory that regards the rock skeleton (solid phase) and pore fluid as an effective whole is used to characterize the effect of horizontal principal stress on rock overall elastic properties and the stress-dependent anisotropy parameters are therefore formulated. Then the approximate P-wave, SV-wave and SH-wave angle-dependent reflection coefficient equations for the horizontal-stress-induced anisotropic media are proposed. It is shown that, on the different reflectors, the stress-induced relative changes in reflectivities (i.e., relative difference) of elastic parameters (i.e., P- and S-wave velocities and density) are much less than the changes in contrasts of anisotropy parameters. Therefore, the effects of stress change on the reflectivities of three elastic parameters are reasonably neglected to further propose an AVO inversion approach incorporating P-, SH- and SV-wave information to estimate the change in horizontal principal stress from the corresponding time-lapse seismic data. Compared with the existing methods, our method eliminates the need for man-made rock-physical or fitting parameters, providing more stable predictive power. 1D test illustrates that the estimated result from time-lapse P-wave reflection data shows the most reasonable agreement with the real model, while the estimated result from SH-wave reflection data shows the largest bias. 2D test illustrates the feasibility of the proposed inversion method for estimating the change in horizontal stress from P-wave time-lapse seismic data. 展开更多
关键词 Monitoring change in horizontal stress Multi-wave reflection coefficients Nonlinear elasticity theory time-lapse seismic data
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Influence of Different Quality Sperm on Early Embryo Morphokinetic Parameters and Cleavage Patterns:A Retrospective Time-lapse Study 被引量:2
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作者 Qiu-yue LIAO Bo HUANG +4 位作者 Si-jia ZHANG Jing CHEN Ge CHEN Ke-zhen LI Ji-hui AI 《Current Medical Science》 SCIE CAS 2020年第5期960-967,共8页
To investigate whether sperm with low concentration and motility can impact preimplantation embryos and to analyze how the effects present under a time-lapse incubation system,2905 oocytes were collected from 219 coup... To investigate whether sperm with low concentration and motility can impact preimplantation embryos and to analyze how the effects present under a time-lapse incubation system,2905 oocytes were collected from 219 couples between January 2014 and December 2015.Patients were divided into three groups according to sperm quality.Morphokinetic parameters and six cleavage patterns in the initial three cleavages were evaluated using the Primo Vision system.Embryo quality and clinic outcomes such as implantation rate,pregnancy rate and live birth rate were measured.The results showed that the concentration and motility of sperm correlated strongly with the rate of 2PN embryos,good-quality embryos on D3,blastocysts on D5/6 and good quality embryos on D5/6.The time-lapse system recordings showed that compromised sperm quality could result in a significant delay in cc l and a decrease in cc2,and impact embryo developmental potential mainly through large fragments or/and blastomere fragmentation in the initial three cleavages.In conclusion,sperm with low concentration and motility can have paternal effects on preimplantation embryos.These paternal effects present both as changes in morphokinetic parameters and cleavage patterns,which occur as early as fertilization and may cause severe damage to the preimplantation embryos. 展开更多
关键词 embryo development patermal effect time-lapse morphokinetic parameters cleavage patterns
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基于re3data的中英科学数据仓储平台对比研究 被引量:1
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作者 袁烨 陈媛媛 《数字图书馆论坛》 CSSCI 2024年第2期13-23,共11页
以re3data为数据获取源,选取中英两国406个科学数据仓储为研究对象,从分布特征、责任类型、仓储许可、技术标准及质量标准等5个方面、11个指标对两国科学数据仓储的建设情况进行对比分析,试图为我国数据仓储的可持续发展提出建议:广泛... 以re3data为数据获取源,选取中英两国406个科学数据仓储为研究对象,从分布特征、责任类型、仓储许可、技术标准及质量标准等5个方面、11个指标对两国科学数据仓储的建设情况进行对比分析,试图为我国数据仓储的可持续发展提出建议:广泛联结国内外异质机构,推进多学科领域的交流与合作,有效扩充仓储许可权限与类型,优化技术标准的应用现况,提高元数据使用的灵活性。 展开更多
关键词 科学数据 数据仓储平台 re3data 中国 英国
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应用Time-lapse研究人3PN胚胎的卵裂模式 被引量:1
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作者 史艳彬 马超 +1 位作者 余巧巧 邵小光 《生殖医学杂志》 CAS 2019年第10期1158-1161,共4页
目的比较IVF3PN、IVF2PN、ICSI3PN和ICSI2PN胚胎的卵裂模式和胚胎动力学参数的差异。方法回顾性分析2017年7月至2018年6月在我院生殖中心就诊经时差胚胎监测(Time-lapse)培养箱培养的393个胚胎发育动力学参数,根据受精结局分为4组:IVF3P... 目的比较IVF3PN、IVF2PN、ICSI3PN和ICSI2PN胚胎的卵裂模式和胚胎动力学参数的差异。方法回顾性分析2017年7月至2018年6月在我院生殖中心就诊经时差胚胎监测(Time-lapse)培养箱培养的393个胚胎发育动力学参数,根据受精结局分为4组:IVF3PN组(n=132)、IVF2PN组(n=150)、ICSI3PN组(n=11)和ICSI2PN组(n=100),分析比较各组胚胎的卵裂模式和原核出现时间、原核消失时间、第一次卵裂时间、t4、t3-t5等胚胎动力学参数。结果IVF3PN组胚胎第一次卵裂模式异常率(100%)显著高于IVF2PN组胚胎(4.67%)、ICSI3PN组胚胎(18.18%)和ICSI2PN组胚胎(5.00%)(P<0.001),而ICSI3PN组、ICSI2PN组和IVF2PN组胚胎之间的第一次卵裂模式异常率无显著差异(P>0.05)。IVF3PN组胚胎原核消失时间[(25.76±1.33)h]显著长于IVF2PN组[(21.43±1.76)h]、ICSI3PN组[(21.86±1.63)h]和ICSI2PN组[(20.14±1.78)h](P<0.05),IVF3PN胚胎第一次卵裂时间亦显著长于其余3组[(27.06±1.59)hvs.(22.64±1.38)h、(22.32±1.56)h、(22.78±1.66)h](P<0.05);ICSI3PN组、ICSI2PN组和IVF2PN组胚胎之间的原核消失时间和第一次卵裂时间均无显著差异(P>0.05)。结论IVF3PN胚胎与IVF2PN、ICSI3PN和ICSI2PN胚胎的卵裂模式和原核消失时间、第一次卵裂时间等动力学参数不同。 展开更多
关键词 time-lapse 人胚胎 三原核 卵裂模式 胚胎动力学
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Time-lapse培养与传统胚胎培养胚胎发育和临床结局比较以及Time-lapse早期胚胎形态动力学参数应用探讨 被引量:1
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作者 冯播 邱峰龙 +3 位作者 仲纪祥 曹森杨 张荣雪 左阳花 《中国性科学》 2022年第11期108-111,共4页
目的比较Time-lapse及传统胚胎培养对体外受精-胚胎移植(IVF-ET)患者胚胎发育情况及临床结局的影响,探讨Time-lapse胚胎形态动力学参数的应用价值。方法选取扬州大学医学院附属淮安市妇幼保健院142对接受IVF-ET治疗的夫妇的临床资料进... 目的比较Time-lapse及传统胚胎培养对体外受精-胚胎移植(IVF-ET)患者胚胎发育情况及临床结局的影响,探讨Time-lapse胚胎形态动力学参数的应用价值。方法选取扬州大学医学院附属淮安市妇幼保健院142对接受IVF-ET治疗的夫妇的临床资料进行回顾性分析,共纳入142个IVF-ET新鲜周期,按照胚胎培养方法分为观察组(n=55)和对照组(n=87)。观察组采用Time-lapse培养箱进行胚胎培养;对照组采用传统培养系统进行胚胎培养。比较两组的获卵数、正常受精数、可移植胚胎数、优质胚胎数、冷冻数及临床妊娠率等指标。比较观察组种植胚胎与未种植胚胎早期胚胎形态动力学参数(t2、t3、t4、t5、cc2及s2),采用受试者工作特征(ROC)曲线评估有差异的时间参数对胚胎种植失败的预测价值。结果观察组可移植胚胎数及囊胚形成数显著高于对照组(P<0.05)。种植胚胎t2、t4、s2、cc2均显著短于未种植胚胎(P<0.05);但t3和t5比较,差异无统计学意义(P>0.05)。ROC曲线显示,t2、t4、s2、cc2对胚胎种植失败有预测价值。结论IVF-ET患者胚胎受精后采用Time-lapse培养,能够提高可移植胚胎数及形成囊胚数;部分早期胚胎动力学参数对新鲜周期移植失败具有一定的预测价值。 展开更多
关键词 time-lapse培养 传统培养 体外受精-胚胎移植 妊娠结局
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