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1Oxidative stress in granulosa cells contributes to poor oocytequality and IVF-ET outcomes in women with polycystic ovarysyndrome显示文摘The increased levels of intraceHular reactive oxygen species (ROS) in granulosa cells (GCs) may allectthe pregnancy results in women with polycystic ovary syndrome (PCOS). In this study, we compared the in vitrofertilization and embryo transfer (IVF-ET) results of 22 patients with PCOS and 25 patients with tubal factorinfertility and detected the ROS levels in the GCs of these two groups. Results showed that the PCOS group hadsignificantly larger follicles on the administration day for human chorionic gonadotropin than the tubal factorgroup (P 〈 0.05); however, the number of retrieved oocytes was not significantly different between the two groups(P 〉 0.05). PCOS group had slightly lower fertilization, cleavage, grade IflI embryo, clinical pregnancy, andimplantation rates and higher miscarriage rate than the tubal factor group (P 〉 0.05). We further found asignificantly higher ROS level of GCs in the PCOS group than in the tubal factor group (P 〈 0.05). The increasedROS levels in GCs caused GC apoptosis, whereas NADPH oxidase 2 (NOX2) specific inhibitors (diphenyleneio-donium and apocynin) significantly reduced the ROS production in the PCOS group. In conclusion, the increasedROS expression levels in PCOS GCs greatly induced cell apoptosis, which further affected the oocyte quality andreduced the positive IVF-ET pregnancy results of women with PCOS. NADPH oxidase pathway may be involvedin the mechanism of ROS production in GCs of women with PCOS.Qiaohong Lai Wenpei Xiang Qing Li Hanwang Zhang Yufeng Li Guijin Zhu Chengliang Xiong Lei Jin 2018Frontiers of Medicine2018,12,5:26
2Study on early warning index of spatial deformation for high concrete dam显示文摘Owing to the deficiency in early warning for high concrete dam,a formula was established to characterize the deformation behavior of high concrete dam as a whole.The early warning index of spatial deformation was calculated by low probability principle on the basis of the deformation entropy formula proposed.The steps were as follows.Firstly,the probability method was utilized to define the degree of order and degree of chaos for each survey point.Secondly,the weight distribution among the survey points was calculated by projection pursuit analysis.Thirdly,the formula of holistic deformation entropy,which can represent the degree of order of high concrete dam,was established on the basis of synergetics and information entropy.Lastly,the early warning index of deformation entropy was computed by low probability method based on series of calculated deformation entropy values.An example showed that the dynamic property of deformation entropy is in accordance with both environmental variables and deflection deformation.Moreover,deformation entropy can be used to improve warning ability and safety management for high concrete dam.LEI Peng CHANG XiaoLin XIAO Feng ZHANG GuiJin SU HuaiZhi 2011Science China(Technological Sciences)2011,54,6:23
3Effects of short-term low temperatures on photosystem Ⅱ function of samara and leaf of Siberian maple (Acer ginnala) and subsequent recovery显示文摘Samara is the reproductive organ (seed) for many tree species in arid land in northwestern China. It is ecologically important in population development due to its dispersal function. However, information on its photosynthesis and effect of environmental stresses on its photosynthesis is still very limited. In the present study, responses of photosystem II (PSII) activity in samara and leaf of Siberian maple to short-term chilling/freezing and subsequent recovery potential were comparatively investigated by using polyphasic fluorescence test. The samara had more efficient photosynthesis (Fv/Fm and PIABS) and more efficient electron transport (φEo) but lower energy dissipation (DIo/RC) than leaf. Generally, the PSII performance and the electron transport for both samara and leaf were inhibited under low temperature stress, accompanied by an increase of energy dissipation in PSII reaction centers (RCs). PSII of both samara and leaf was not markedly affected by chilling and could acclimate to chilling stress. Short-term freezing could completely inhibit PSII activity in both samara and leaf, indicated by the drop of values of Fv/Fm, PIABS, φEo to zero. PSII functional parameters of short-term dark frozen samara could be largely recovered whereas those of frozen leaf could not be recovered. The higher tolerance of samara to short-term low temperature stress than leaf is of great ecological significance for seed development, population establishment of Siberian maple.XiangLiang PAN1, DaoYong ZHANG1,2, Xi CHEN1, Li LI1, GuiJin MU1, LanHai LI1, AnMing BAO1, Jing LIU2, HuaiSong ZHU1, WenJuan SONG1, JianYing YANG1, JunYong AI1 1 Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China 2 State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550000, China 2009Journal of Arid Land2009,1,1:10
4Environmental impact and health risk assessment of volatile organic compound emissions during different seasons in Beijing显示文摘Volatile organic compounds(VOCs)are major contributors to air pollution.Based on the emission characteristics of 99 VOCs that daily measured at 10 am in winter from 15 December 2015 to 17 January 2016 and in summer from 21 July to 25 August 2016 in Beijing,the environmental impact and health risk of VOC were assessed.In the winter polluted days,the secondary organic aerosol formation potential(SOAP)of VOC(199.70±15.05 mg/m^3)was significantly higher than that on other days.And aromatics were the primary contributor(98.03%)to the SOAP during the observation period.Additionally,the result of the ozone formation potential(OFP)showed that ethylene contributed the most to OFP in winter(26.00%and 27.64%on the normal and polluted days).In summer,however,acetaldehyde was the primary contributor to OFP(22.00%and 21.61%on the normal and polluted days).Simultaneously,study showed that hazard ratios and lifetime cancer risk values of acrolein,chloroform,benzene,1,2-dichloroethane,acetaldehyde and 1,3-butadiene exceeded the thresholds established by USEPA,thereby presenting a health risk to the residents.Besides,the ratio of toluene-to-benzene indicated that vehicle exhausts were the main source of VOC pollution in Beijing.The ratio of m-/p-xylene-toethylbenzene demonstrated that there were more prominent atmospheric photochemical reactions in summer than that in winter.Finally,according to the potential source contribution function(PSCF)results,compared with local pollution sources,the spread of pollution from long-distance VOCs had a greater impact on Beijing.Chuanqi Li Qianqian Li Dongge Tong Qingliang Wang Mingge Wu Bohua Sun Guijin Su Li Tan 2020Journal of Environmental Sciences2020,32,7:10
5A preliminary study of chronology for a newly-discovered ancient city and five archaeological sites in Lop Nor, China显示文摘In the past century, it has long been debated in the archeological, historical, geographical, and many other related communities where the capital of the Luolan and Shanshan states was in the Lop Nor region. This paper presents three AMS radiocarbon ages from a newly-discovered ancient city at about 6.3 km to the northwest of the Xiaohe Graveyard, and fifteen new radiocarbon ages from the Loulan (LA), LE, Qieerqiduke, Milan, and Tuyin sites in Lop Nor. The new investigation shows that the age of newly-discovered ancient city is at ca. 440–500 AD, belonging to the Northern Wei Dynasty (386–534 AD). This is about 100–300 years younger than Loulan (ca. 100–230 AD), LE (ca. 230–300 AD), Qieerqiduke (ca. 200 AD), and Tuyin (ca. 100 AD). A wooden beam from Milan fortress is dated to ca. 370 AD, while the age on north wall at west gate of the fortress is younger, around 770 AD, suggesting that its construction time might be at the Tang Dynasty. According to 14C ages, cultural relic style, and the geographical location, the newly-discovered ancient city is probably attributed to 'Zhubin City', as documented in the historical literature. Temporally, we name the city 'ancient Zhubin River City'. However, the characteristics and functions of this ancient city are largely unknown and need more detailed archaeological excavation and investigation in the future. Given its location near the ancient postal relay of Alagan on the crossroad, there is no doubt that the newly-discovered city was at an important geographical position on the Silk Road, no matter whether it was called 'Zhubin City', or 'Lielo City', or the capital of Loulan state–'Yuni City'. Our findings provide new evidence for the temporal and spatial distribution of ancient relic sites and the development of civilization in western China, thus contributing to our understanding of the relationship between human activities and environmental change in the Lop Nor region.LU HouYuan XIA XunCheng LIU JiaQi QIN XiaoGuang WANG FuBao YIDILISI Abuduresule ZHOU Li Ping MU GuiJin JIAO YingXin LI JingZhi 2010Chinese Science Bulletin2010,55,1:8
6Image Signature Based Mean Square Error for Image Quality Assessment显示文摘Motivated by the importance of Human visual system(HVS) in image processing, we propose a novel Image signature based mean square error(ISMSE)metric for full reference Image quality assessment(IQA).Efficient image signature based describer is used to predict visual saliency map of the reference image. The saliency map is incorporated into luminance difference between the reference and distorted images to obtain image quality score. The effect of luminance difference on visual quality with larger saliency value which is usually corresponding to foreground objects is highlighted. Experimental results on LIVE database release 2 show that by integrating the effects of image signature based saliency on luminance difference, the proposed ISMSE metric outperforms several state-of-the-art HVS-based IQA metrics but with lower complexity.CUI Ziguan GAN Zongliang TANG Guijin LIU Feng ZHU Xiuchang 2015Chinese Journal of Electronics2015,24,4:5
7Determination of hexabromocyclododecanes in sediments from the Haihe River in China by an optimized HPLC–MS–MS method显示文摘Hexabromocyclododecanes(HBCDs),a new type of persistent organic pollutants widely used as brominated flame retardants,have attracted wide attention due to their increasing level and toxicity. A method based on high-performance liquid chromatography mass spectrometry(HPLC–MS–MS)in electrospray ionization mode has been developed by optimization of various parameters,which effectively improved the separation degree and responsive intensity of α-,β-and γ-HBCD isomers. The concentrations and distribution profiles of three HBCD isomers were investigated in sediments from the Haihe River in China.It was observed that the concentrations of HBCDs varied in the range of 0.4–58.82 ng/g,showing a decreasing trend along the flow direction,possibly due to attenuation and biodegradation along the flow direction of the Haihe River. The distribution profile of α-,β-,γ-HBCD was 7.91%–88.6%,0–91.47%,and 0.62%–42.83%,respectively. Interestingly,α-HBCD dominated in most sample sites. This was different from the distribution profile in commercial industrial products,which might be attributed to the inter-transformation and different degradation rates of the three HBCD isomers. The potential ecological risk of HBCDs in sediment was characterized under the two-tiered procedure of the European Medicines Evaluation Agency for environmental risk assessment. Although the HBCDs in the selected section of the Haihe River presented 'no risk' in the sediment compartment,its risk in sediment cannot be neglected since sediment is one of the important sinks and reservoirs of pollutants.Yanhui Zhao Qianqian Li Xue Miao Xinchen Huang Binke Li Guijin Su Minghui Zheng 2017Journal of Environmental Sciences2017,29,5:5
8Decomposition of hexachlorobenzene over Al_2O_3 supported metal oxidecatalysts显示文摘Decomposition of hexachlorobenzene(HCB)was investigated over several metal oxides(i.e.,MgO,CaO,BaO,La2O3,CeO2,MnO2, Fe2O3,and Co3O4)supported on Al2O3,which was achieved in closed system at a temperature of 300°C.Catalysts were prepared by incipient wetness impregnation with different metal oxides loading and impregnating solvents.The decomposition effciency of different catalysts for this reaction depends on the nature of the metal oxide used,and Al2O3 supported La2O3 was found to be the most active one.Pentachlorobenzene(PeCB),and all tetrachlorobenzene(TeCB),trichlorobenzene(TrCB),and dichlorobenzene(DCB)isomers were detected after the decomposition reaction,indicating that the decomposition was mainly a dechlorination process.The detection of all lower chlorinated benzenes suggested the complexity of decomposition and the presence of more than one dechlorination pathway.Lifei ZHANG Minghui ZHENG Bing ZHANG Wenbin LIU Lirong GAO Te BA Zhiyuan REN Guijin SU 2008Journal of Environmental Sciences2008,20,12:4
9Estimation of the rational water area for controlling wind erosion in the dried-up basin of the Ebinur Lake and its effect detection显示文摘埃比纳·莱克区域被描述为“一个格林迷宫”在“ Xinjiang MapRecords:河的记录“然而,在 1910 出版了在这个区域的生态学和环境严重由于人的活动的影响被堕落了在期间最近 40 年。渴起来,有 107.4 km^2 的一个区域的湖盆在它的西北的部分形成,是没有植被,盖住 byunconsolidated 淤泥沉积物,并且在北方 Xinjiang 成为了灰尘天气的主要灰尘来源之一,并且有 4.8x10 ~ 6t 的年度数量的灰尘被大风从有 164 天的 Alataw 山脉差距从这个区域吹一年里的发生的大风。为在弄干起来的湖盆在湖区域和有效地控制的风侵蚀改进生态学的埃比纳·莱克的合理的水区域和流入在在弄干起来的湖盆分析在沉积物的小粒的作文之间的当前的生态的问题和关系以后用水平衡方程被估计并且灰尘天气,和最近的年里的生态的效果被监视。为在弄干起来的湖盆在湖区域和有效地控制的风侵蚀改进生态学的 theEbinur 湖的水区域应该至少是 800 km^2,这被考虑,并且湖应该在 7.92x10 ~ 上的再装的表面流量和地下水的年度体积 8 m^3。BAO Anming MU Guijin ZHANG Yi FENG Xianwei CHANG Cun YIN Xiaojun 2006Chinese Science Bulletin2006,51,A01:4
10Polychlorinated dibenzo-p-dioxins and dibenzofurans in different tissues of the cormorants (Phalacrocorax carbo) from Dongting Lake,China显示文摘Tissue distribution provides important information regarding the pharmacokinetic behavior of pollutants and is invaluable when analyzing the risk posed to avian species by the exposure to such kind of pollutants.In this study,concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in muscle,liver,spleen,kidney,stomach,gall bladder,skin,heart,pancreas,intestine and lung tissue extracts of cormorants collected from Dongting Lake,China.Tissue distribution results showed preferential accumulation of PCDD/Fs in both liver and skin.The total concentration of PCDD/Fs ranged from 421 to 5696 pg/g lipid weight.Octachlorinated dibenzo-p-dioxin (OCDD) was the predominant congener in all tissues and contributed between 31% and 82% to all 17 PCDD/Fs in different tissues.The liver/muscle ratios progressively increased with the degree of chlorination of PCDDs,except for OCDD.The relative toxic potential of PCDDs and PCDFs in tissues were calculated using the World Health Organization (WHO) Toxic Equivalency Factors (TEFs) for birds.The concentrations of WHO-toxic equivalent in different tissues ranged between 14.8 and 2021 pg/g lipid weight.These results indicated PCDD/Fs may have been bio-accumulated in cormorant via food-web.Furthermore,when compared with studies reported in the literatures,the PCDD/Fs levels in the cormorant collected from Dongting Lake were still relatively high.Lirong Gaol Minghui Zheng Bing Zhang Wenbin Liu Ke Xiao Guijin Su Qinghua Zhang 2011Journal of Environmental Sciences2011,23,10:4
11Synthesis of a magnetic micro/nano Fe_xO_y-CeO_2 composite and its application for degradation of hexachlorobenzene显示文摘A micrometer-sized nanostructured,magnetic,ball-like FexOy-CeO2 composite was synthesized through an ethylene-glycol mediated process.The synthesized samples were characterized by scanning electron microscopy combined with energydisperse X-ray analysis,transmission electron microscopy and X-ray powder diffraction.In the synthesis system,polyethylene glycol (PEG) and urea were found to play significant roles in the formation of the micrometer-sized spherical architecture of the precursor.The details of morphology and particle size could be changed with the initial concentration of Fe(NO3)3-9H2O and Ce(NO3)3-6H2O as the reactants.The magnetic FexOy-CeO2 composite with a similar morphology was readily obtained by calcination from the precursor.The characterization of transmission electron microscopy showed the calcined ball-like architecture was a highly porous structure consisting of many nanoparticles.Because of the micrometer-sized nanostructure and the multi-components as well as the magnetism,the as-obtained FexOy-CeO2 composite showed better activity and potentially easy recovery for the harmless degradation of hexachlorobenzene (HCB).JIA ManKe,SU GuiJin,ZHENG MingHui,ZHANG Bing & LIN ShiJing State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China 2010Science China Chemistry2010,53,6:3
12A Hand Gesture Based Interactive Presentation System Utilizing Heterogeneous Cameras显示文摘In this paper, a real-time system that utilizes hand gestures to interactively control the presentation is proposed. The system employs a thermal camera for robust human body segmentation to handle the complex background and varying illumination posed by the projector. A fast and robust hand localization algorithm is proposed, with which the head, torso, and arm are sequentially localized. Hand trajectories are segmented and recognized as gestures for interactions. A dual-step calibration algorithm is utilized to map the interaction regions between the thermal camera and the projected contents by integrating a Web camera. Experiments show that the system has a high recognition rate for hand gestures, and corresponding interactions can be performed correctly.Bobo Zeng Guijin Wang Xinggang Lin 2012Tsinghua Science and Technology2012,17,3:2
13Enhancing the stability of astaxanthin by encapsulation in poly (1-lactic acid) microspheres using a supercritical anti-solvent process显示文摘To improve the physicochemical properties of astaxanthin, it was encapsulated in poly (1-lactic acid)(PLLA) using a supercritical anti-solvent (SAS) process with dichloromethane/acetone mixture as the solvent, and supercritical CO2 as the anti-solvent. The effects of altering five SAS operating cond让ions, solvent ratio, temperature, pressure, concentration of carrier, and flow rate, on the microstructure of particles were investigated using an orthogonal experimental design. Under the optimal conditions, astaxanthin/PLLA particles were produced with an encapsulation efficiency of 91.5% and a mean particle size of 954.6 nm. SEM images showed that most astaxanthin/PLLA particles were uniform microspheres. FT-IR spectra showed that the chemical structure of astaxanthin was unchanged by the SAS process. The results of chromatic difference, X-ray diffraction, thermogravimetric, and differential scanning calorimetry analyses showed that astaxanthin had been encapsulated in the PLLA matrix in an amorphous state. Overall, astaxanthin/PLLA microspheres greatly enhanced the stability of astaxanthin during storage, and the levels of residual solvents were far lower than the ICH lim让s. This means that astaxanthin/PLLA microspheres prepared using SAS show great potential for use in many food, cosmetic, and pharmaceutical formulations.Guijin Liu Man Hu Ziyi Zhao Qing Lin Dongwei Wei Yanbin Jiang 2019Particuology2019,17,3:2
14Transition from source-to stress-controlled plasticity in nanotwinned materials below a softening temperature显示文摘Nanotwinned materials have been widely studied as a promising class of nanostructured materials that exhibit an exceptional combination of high strength,good ductility,large fracture toughness,remarkable fatigue resistance,and creep stability.Recently,an apparent controversy has emerged with respect to how the strength of nanotwinned materials varies as the twin thickness is reduced.While a transition from hardening to softening was observed in nanotwinned Cu when the twin thickness is reduced below a critical value,continuous hardening was reported in nanotwinned ceramics and nanotwinned diamond.Here,by conducting atomistic simulations and developing a theoretical modeling of nanotwinned Pd and Cu systems,we discovered that there exists a softening temperature,below which the material hardens continuously as the twin thickness is reduced(as in nanotwinned ceramics and diamond),while above which the strength first increases and then decreases,exhibiting a maximum strength and a hardening to softening transition at a critical twin thickness(as in nanotwinned Cu).This important phenomenon has been attributed to a transition from source-to stress-controlled plasticity below the softening temperature,and suggests that different hardening behaviors may exist even in the same nanotwinned material depending on the temperature and that at a given temperature,different materials could exhibit different hardening behaviors depending on their softening temperature.Seyedeh Mohadeseh Taheri Mousavi Haofei Zhou Guijin Zou Huajian Gao 2019npj Computational Materials2019,,1:2
15Wind erosion at the dry-up bottom of Aiby Lake-A case study on the source of air dust显示文摘Mu Guijin Yan Shun Jilili Abuduwanli 2002Science in China (Series D: Earth Sciences)2002,45,1:1
16Distribution of DDT in a Typical DDT Waste Contaminated Site显示文摘Wenbin Liu Changliang Li Minghui Zheng Li Wang Sumei Li Te Ba Guijin Su Lirong Gao Lifei Zhang 2008Bulletin of Environmental Contamination and Toxicology2008,,3:1
17Human activity during the late Pleistocene in the Lop Nur region, northwest China: Evidence from a buried stone artifact显示文摘The Lop Nur region, in the east part of Tarim Basin, was an important transportation junction between west and east,north and south Eurasia. However, previous studies on prehistoric human activity have concentrated mostly on the Bronze Age,whereas that during the Stone Age remains largely unresearched. Here, we present a new direct evidence of human activity in the late Pleistocene, recorded on a grinding stone buried in a lacustrine sediment section of the Lop Nur region. The grain size distribution of the sediment section indicates that the site was probably in the center of a lake with weak hydrodynamic environment. Therefore, the stone artifact can only be carried to here by people instead of river and it was never move as soon as left here. Results of radiocarbon dating, the evident stratigraphic relations between the stone artifact and the sedimentary formation, indicate that the human activity could extend to approximately 13 ka BP. Furthermore, the results of starch-grain and use-wear analyses suggest that ancient humans gathered seeds of Triticeae, roots, and tubers and used the grinding stone to simply process selected plant as plant foodstuffs during this period. It implies that the environmental conditions in the river delta of the Lop Nur were inhabitable during the late Pleistocene.Kangkang LI Xiaoguang QIN Xiaoyan YANG Bing XU Lei ZHANG Guijin MU Dong WEI Chunxue WANG Yong WU Xiaohong TIAN Yongchong LIN Wen LI Jiaqi LIU Yinxin JIAO 2018Science China Earth Sciences2018,61,11:1
18Multi-object tracking based on deep associated features for UAV applications显示文摘Multi-object tracking(MOT) techniques have been increasingly applied in a diverse range of tasks. Unmanned aerial vehicle(UAV) is one of its typical application scenarios. Due to the scene complexity and the low resolution of moving targets in UAV applications, it is difficult to extract target features and identify them. In order to solve this problem, we propose a new re-identification(re-ID) network to extract association features for tracking in the association stage. Moreover, in order to reduce the complexity of detection model, we perform the lightweight optimization for it. Experimental results show that the proposed re-ID network can effectively reduce the number of identity switches, and surpass current state-of-the-art algorithms. In the meantime, the optimized detector can increase the speed by 27% owing to its lightweight design, which enables it to further meet the requirements of UAV tracking tasks.XIONG Lingyu TANG Guijin 2023Optoelectronics Letters2023,19,2:1
19Characterizing variations in soil particle size distribution in oasis farmlands—A case study of the Cele Oasis显示文摘Dongwei Gui Jiaqiang Lei Fanjiang Zeng Guijin Mu Juntao Zhu Hui Wang Qiang Zhang 2009Mathematical and Computer Modelling2009,,11:1
20Study of scientific literacy practical teaching evaluation based on AHP显示文摘Zhang Fengrong Xu Zhifeng Chen Zhimin Yin Guijin Huang Fang 2009ISECS International Colloquium on Volume2009,,3:1
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