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Sperm retrieval rates and clinical outcomes for patients with different causes of azoospermia who undergo microdissection testicular sperm extraction-intracytoplasmic sperm injection

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Asian Journal of Andrology 2021年第1期23卷 59-63页

作者： Hong-Liang Zhang Lian-Ming zhao Jia-Ming Mao De-Feng Liu Wen-Hao Tang Hao-Cheng Lin Li Zhang Ying Lian Kai Hong hui Jiang Department of Urology Peking University Third HospitalBeijing 100191China Department of Reproductive Medicine Center Peking University Third HospitalBeijing 100191China Department of Andrology Peking University Third HospitalBeijing 100191China Department of Human Sperm Bank Peking University Third HospitalBeijing 100191China

The aim of our study was to compare the sperm retrieval rates(SRRs)and clinical outcomes of patients with different causes of azoospermia who underwent microdissection testicular sperm extraction-intracytoplasmic sperm injection(micro-TESE-ICSI).We conducted a retrospective study at the Reproductive Medicine Center of Peking University Third Hospital in Beijing,China,from January 2014 to December *** study examined 769 patients with nonobstructive azoospermia who underwent 347 cycles of *** with azoospermia were classified into Group A(Klinefelter syndrome,n=284,125 cycles),Group B(azoospermia Y chromosome factor c[AZFc]microdeletion,n=91,64 cycles),Group C(cryptorchidism,n=52,39 cycles),Group D(previous mumps and bilateral orchitis,n=23,23 cycles),and Group E(idiopathic azoospermia,n=319,96 cycles).Clinical characteristics,SRR,embryonic development,and pregnancy outcomes of the patients were compared between all *** in Group D had the highest and most successful *** average SRR for all patients was 46.0%.The rates of clinical pregnancy,implantation,and live birth in Group D were 78.3%,65.0%,and 74.0%,respectively,which were higher than those in all other groups(P0.05).Patients with orchitis had the highest SRR and best clinical *** AZFc microdeletion patients had a higher SRR,their clinical outcomes were worse.

关键词： azoospermia intracytoplasmic sperm injection microdissection testicular sperm extraction pregnancy outcomes sperm retrieval rate

Evaluation of nine machine learning methods for estimating daily land surface radiation budget from MODIS satellite data

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International Journal of Digital Earth 2022年第1期15卷 1784-1816页

作者： Shaopeng Li Bo Jiang Shunlin Liang Jianghai Peng hui Liang Jiakun Han Xiuwan Yin Yunjun Yao Xiaotong Zhang Jie Cheng Xiang zhao Qiang Liu Kun Jia The State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of SciencesBeijingPeople’s Republic of China Beijing Engineering Research Center for Global Land Remote Sensing Products Institute of Remote Sensing Science and EngineeringFaculty of Geographical ScienceBeijing Normal UniversityBeijingPeople’s Republic of China Department of Geographical Sciences University of MarylandCollege ParkMDUSA Beijing Engineering Research Center for Global Land Remote Sensing Products College of Global Change and Earth System ScienceBeijing Normal UniversityBeijingPeople’s Republic of China

The all-wave net radiation(Rn)at the land surface represents surface radiation budget and plays an important role in the Earth's energy and water *** studies have been conducted to estimate from satellite top-of-atmosphere(TOA)data using various methods,particularly the application of machine learning(ML)and deep learning(DL).However,few studies have been conducted to provide a comprehensive evaluation about various ML and DL methods in *** on extensive in situ measurements distributed at mid-low latitudes,the corresponding Moderate Resolution Imaging Spectroradiometer(MODIS)TOA observations,and the daily from the fifth generation of European Centre for Medium-Range Weather Forecasts Reanalysis 5(ERA5)used as a priori knowledge,this study assessed nine models for daily estimation,including six classic ML methods(random forest-RF,adaptive boosting-Adaboost,extreme gradient boosting-XGBoost,multilayer perceptron-MLP,radial basis function neural network-RBF,and support vector machine-SVM)and three DL methods(multilayer perceptron neural network with stacked autoencoders-SAE,deep belief network-DBN and residual neural network-ResNet).The validation results showed that the three DL methods were generally better than the six ML methods except XGBoost,although they all performed poorly in certain conditions such as winter days,rugged terrain,and high *** had the most robust performance across different land cover types,elevations,seasons,and latitude zones,but it has disadvantages in practice because of its highly configurable implementation environment and low computational *** estimated daily values from all nine models were more accurate than the corresponding Global LAnd Surface Satellite(GLASS)product.

关键词： Net radiation energy balance mid-low latitude model comparison machine learning deep learning MODIS ERA5

Rapid increase in warm-wet compound extreme events with high health risks in southern China:Joint influence of ENSO and the Indian Ocean

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Advances in Climate Change Research 2023年第6期14卷 856-865页

作者： Cai-Meng LIANG Liang zhao Shun-Wu ZHOU Xin-Yong SHEN Cun-Rui HUANG Yi-hui DING Yan-Ju LIU Hao-Xin YAO Kai-Xing ZHOU Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Numerical Modeling for Atmosphere Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academyof SciencesBeijing100029China Key Laboratory of South China Sea Meteorological Disaster Prevention and Mitigation of Hainan Province Haikou 570203China Vanke School of Public Health Tsinghua UniversityBejing 100084China Institute of Healthy China Tsinghua UniversityBeijing 100084China National Climate Center China Meteorological AdministrationBejing 100081China Beijing Institute of Electronic System Engineering Bejing 100854China

High temperature and high humidity pose notable threats to the health and survival of humans,and the impact of compound extreme events involving multiple meteorological elements is usually greater than the sum of the impacts of individual extreme ***,there is limited research on the compound extreme meteorological events,defined based on the extreme of health risks rather than just the extreme of meteoro-logical elements,necessitating further investigation into their characteristics and underlying driving *** daily records of emergency ambulance dispatches from selected Chinese cities,together with daily average temperature and relative humidity data,this study identified and quantified warm-wet compound extreme events with high health risks(HRWWs)that occurred in southern China during *** revealed that HRWWs were most prevalent in the coastal region of southern *** annual frequency of HRWWs across China underwent a marked shift in 2014,with the rapid increase in recent years primarily contributed by the increase in summer HRWWs and advance and extension of the period of occurrence of HRWWs in *** analysis indicated that the changes in HRWWs in southern China during summer were primarily regulated by the EIl Nino-Southern Oscillation(ENSO)of the preceding winter and the springtime Indian Ocean basin-wide(IOBW)*** Nino and Indian Ocean warming force a reverse Walker circulation in the tropical Indian Ocean-western Pacific,strengthening the Philippine anticyclone(PAC)in *** weakens convection in the northwestern Pacific and enables the western Pacific subtropical high to extend westward over coastal areas of southern *** resulting abnormal atmospheric circulation causes prevailing subsidence over southern China,which is unfavorable for precipitation but conducive to maintaining high surface *** reduced precipitation,water vapor flux is increased owing to strengthened southwesterlies

关键词： Health risk Warm-wet compound events ENSO IOBW

Investigating the efficiency of the Beijing Faint Object Spectrograph and Camera(BFOSC)of the Xinglong 2.16-m reflector

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Research in Astronomy and Astrophysics 2018年第9期18卷 53-62页

作者： Yong zhao Zhou Fan Juan-Juan Ren Liang Ge Xiao-Ming Zhang Hong-Bin Li hui-Juan Wang Jian-Feng Wang Peng Qiu Xiao-Jun Jiang Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

The Beijing Faint Object Spectrograph and Camera （BFOSC） is one of the most important instruments operating in conjunction with the 2.16-m telescope at Xinglong Observatory. Every year there are - 20 SCI-papers published based on observational data acquired with this telescope. In this work, we have systemically measured the total efficiency of the BFOSC that operates as part of the 2.16-m reflector, based on observations of two ESO flux standard stars. We have obtained the total efficiencies of the BFOSC instrument of different grisms with various slit widths in almost all ranges, and analyzed factors which effect the efficiency of this telescope and spectrograph. For astronomical observers, the result will be useful for them to select a suitable slit width, depending on their scientific goals and weather conditions during observations. For technicians, the result will help them to systemically identify the real efficiency of the telescope and spectrograph, and to further improve the total efficiency and observing capacity of the telescope technically.

关键词： astronomical instrumentation methods and techniques - instrumentation: spectrographs

Nanotechnology-assisted adipose-derived stem cell （ADSC） therapy for erectile dysfunction of cavernous nerve injury： In vivo cell tracking, optimized injection dosage, and functional evaluation

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Asian Journal of Andrology 2018年第5期20卷 442-447页

作者： Han Wu Wen-Hao Tang Lian-Ming zhao De-Feng Liu Yu-Zhuo Yang Hai-Tao Zhang Zhe Zhang Kai Hong Hao-Cheng Lin hui Jiang Department of Urology Peking University Third Hospital Beijing 100191 China Department of Reproductive Medicine Center Peking University Third Hospital Beijing 100191 China Department of Andrology Peking University Third Hospital Beijing 100191 China Department of Human Sperm Bank Peking University Third Hospital Beijing 100191 China

Stem cell therapy is a potentially promising option for erectile dysfunction; however, its risk of tumorigenicity is a clinical hurdle and the risk is positively related to the number of injected cells. Our previous study showed that nanotechnology improved adipose-derived stem cell （ADSC） therapy for erectile dysfunction of cavernous nerve injury （CNI） by attracting cells in the corpus cavernosum. These results indicated the possibility of using a reduced dosage of ADSCs for intracavernous injection. In this exploratory study, we used lower dosage （2 × 105 cells） of ADSCs for intracavernous injection （ICI） and the nanotechnology approach. Intracavernous pressure and mean arterial pressure were measured at day 28 to assess erectile function. The low-dose ADSC therapy group showed favorable treatment effects, and nanotechnology further improved these effects. In vivo imaging of ICI cells revealed that the fluorescein signals of NanoShuttle-bound ADSCs （NanoADSCs） were much stronger than those of ADSCs at days 0, 1, and 3. Both immunofluorescence and Western blot analysis showed a significant increase in smooth muscle, endothelium, and nerve tissue in the ADSC group compared to that in the CNI group; further improvement was achieved with assisted nanotechnology. These findings demonstrate that nanotechnology can be used to further improve the effect of small dosage of ADSCs to improve erectile function. Abundant NanoADSCs remain in the corpus cavernosum in vivo for at least 3 days. The mechanism of erectile function improvement may be related to the regeneration of the smooth muscle, endothelium, and nerve tissues.

关键词： adipose-derived stem cell (ADSC) cavernous nerve injury cell tracking erectile dysfunction

A bi-level optimal scheduling model for new-type power systems integrating large-scale renewable energy

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Clean Energy 2022年第6期6卷 931-943页

作者： huiru zhao Chao Zhang Yihang zhao School of Economics and Management North China Electric Power UniversityBeijing 102206China

The construction of a new type of power system is a key way to achieve the goal of‘carbon peaking and carbon neutrality’.In the process of developing renewable energy,large-scale wind and photovoltaic power systems replace conventional units,which will have an impact on the stability of the power *** eliminate these concerns,this paper proposes a bi-level optimal scheduling model for new-type power *** upper level aims to minimize fluctuation of net load,with the consideration of demand response,to smooth the load *** lower level takes the minimum operating cost of the new-type power system as the objective function and the most economical scheduling strategy is *** deal with the uncertainty of renewable energy integrated within the system,the lower model is transformed into a two-stage robust optimization model and solved by applying a column-and-constraint generation ***,a regional power system is selected to conduct a case study comprising 760 MW thermal power,50 MW·h energy storage,200 MW wind turbine and 150 MW photovoltaic *** results show that the constructed two-stage robust optimization model is conducive to establishing the most economical scheduling scheme of the system with an uncertain budget and the minimum operation cost is$45,*** addition,demand response and energy storage can reduce peak-to-valley differences in the power system.

关键词： wind power photovoltaic power demand response new-type power system bi-level optimization robust optimization

Ginsenoside Rb1 inhibits oxidative stress-induced ovarian granulosa cell injury through Akt-FoxO1 interaction

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Science China(Life Sciences) 2022年第11期65卷 2301-2315页

作者： Ping Zhou Feng Deng Zi Yang Canhui Cao Hongcui zhao Fenting Liu Ke Zhong Lin Fu Tianliu Peng Di Sun hui Liu Rong Li Yang Yu Center for Reproductive Medicine Department of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China Key Laboratory of Assisted Reproduction(Peking University) Ministry of EducationBeijing 100191China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing 100191China National Clinical Research Center for Obstetrics and Gynecology(Peking University Third Hospital) Beijing 100191China Clinical Stem Cell Research Center Peking University Third HospitalBeijing 100191China

Ginsenoside Rb1 shows a strong antioxidant effect and has potential activation effects on *** aim of the present study was to investigate the protective effect of Rb1 on age-related ovarian granulosa cell *** granulosa cells(GCs)were obtained from 50 young women(≤30 years)and 50 aged women(≥38 years)at an IVF *** and aged ICR mice were administered with or without Rb1(10 mg kg^(-1),i.p.)for 2 *** protective effects of Rb1 were investigated and the role of Rb1 on the modulation of Akt-FoxO1 interaction was determined with immunofluorescence,Western blotting,immunoprecipitation,si RNA silencing and pharmacological ***1 effectively decreased LDH and MDA,and reversed the apoptotic-related protein levels in h GL cells from old *** results were found in *** addition,the mitochondrial membrane potential was restored and the overaccumulation of ROS was reversed by ***1 preserved peroxide-impaired Akt activation,to some extent,by increasing phosphorylation at ***1 also facilitated p-Akt binding to FoxO1 and promoted the phosphorylation of *** RNA silencing of Akt,Akt inhibitor LY294002,and FoxO1 inhibitor AS1842856 attenuated the effects of *** Rb1 inhibits age-related GCs oxidative damage by activating Akt phosphorylation at Ser473 and by further interaction with FoxO1.

关键词： ginsenoside Rb1 oxidative stress aging granulosa cell Akt FoxO1

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黄芪土壤的红外指纹图谱特征及其比较研究

光谱学与光谱分析 2012年第11期32卷 2981-2986页

作者：刘必旺赵慧辉赵平王伟薛慧清王永辉周然刘养清山西中医学院山西太原030024 北京中医药大学北京100029 天津药明康德新药开发有限公司天津300457

利用简便、快速、分辨率高,信息丰富的FTIR,对道地黄芪产地:山西省浑源县官儿乡的6个产地;应县白马石乡的3个产地;繁峙县周庄;内蒙古固阳县的2个产地及其这些产地各4个生长年限生长黄芪的土壤样品(共计42个),进行了较详细的研究,得到了... 详细信息

利用简便、快速、分辨率高,信息丰富的FTIR,对道地黄芪产地:山西省浑源县官儿乡的6个产地;应县白马石乡的3个产地;繁峙县周庄;内蒙古固阳县的2个产地及其这些产地各4个生长年限生长黄芪的土壤样品(共计42个),进行了较详细的研究,得到了一些有益的结论:黄芪土壤FTIR特征不同于一般土壤;不同产地黄芪土壤的FTIR特征有别,黄芪品质各异;黄芪土壤FTIR特征与党参土壤大不相同;FTIR指纹图谱可以为中药种植的地域选择提供重要信息。

关键词：黄芪土壤红外指纹图谱特征比较

Live facial feature extraction

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Science in China(Series F) 2008年第5期51卷 489-498页

作者： zhao JieYu Research Institute of Computer Science and Technology Ningbo University Ningbo 315211 China

Precise facial feature extraction is essential to the high-level face recognition and expression analysis. This paper presents a novel method for the real-time geometric facial feature extraction from live video. In this paper, the input image is viewed as a weighted graph. The segmentation of the pixels corresponding to the edges of facial components of the mouth, eyes, brows, and nose is implemented by means of random walks on the weighted graph. The graph has an 8-connected lattice structure and the weight value associated with each edge reflects the likelihood that a random walker will cross that edge. The random walks simulate an anisot- ropic diffusion process that filters out the noise while preserving the facial expression pixels. The seeds for the segmentation are obtained from a color and motion detector. The segmented facial pixels are represented with linked lists in the origi- nal geometric form and grouped into different parts corresponding to facial components. For the convenience of implementing high-level vision, the geometric description of facial component pixels is further decomposed into shape and reg- istration information. Shape is defined as the geometric information that is invariant under the registration transformation, such as translation, rotation, and isotropic scale. Statistical shape analysis is carried out to capture global facial fea- tures where the Procrustes shape distance measure is adopted. A Bayesian ap- proach is used to incorporate high-level prior knowledge of face structure. Experimental results show that the proposed method is capable of real-time extraction of precise geometric facial features from live video. The feature extraction is robust against the illumination changes, scale variation, head rotations, and hand interference.

关键词： live facial feature extraction random walks anisotropic diffusion process statistical shape analysis