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Diversity order of decode-and-forward MIMO relaying with transmit antenna selection

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 1-7页

作者： CAO Lei YANG hong-wen zhang xin YANG Da-cheng School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article analyzes the diversity order of several proposed schemes, where the transmit antenna selection （TAS） strategies are combined with low-complexity decode-and-forward （DF） protocols in the multiple-input multiple-output （MIMO） relaying scenario. Although antenna selection is a suboptimal form of beamforming, it enjoys the advantages of tractable optimization and low feedback overhead. Specifically, this article proposes schemes that combine TAS strategies with fixed decode-and-forward （FDF） and selection decode-and-forward （SDF） protocols. Following that, the asymptotic expressions of outage probabilities are derived and the diversity order of the proposed schemes analyzed. These kinds of combination of transmit antenna selection strategies and low-complexity decode-and-forward protocols can achieve partial diversity order in the MIMO relaying scenario. The numerical simulations verify the analysis.

关键词： transmit antenna selection decode-and-forward MIMO relaying outage probability diversity order

Effect of recombinant human bone morphogenetic protein 2/polylactide-co-glycolic acid (rhBMP-2/PLGA) with core decompression on repair of rabbit femoral head necrosis

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Asian Pacific Journal of Tropical Medicine 2014年第11期7卷 895-899页

作者： Zhao-Xun Pan hong-xin zhang Ye-xin Wang Long-Di Zhai Wei Du Department of Joint Surgery No 89 Hospital of People's Liberation Army

Objective:To observe the effect of recombinant human bone morphogenetic protein 2/polylactide-co-glycolic acid(rhBMP-2/PLGA) with core decompression on repair of rabbit femoral head ***:Bilateral femoral head necrosis models of rabbit were established by steroid injection.A total of 48 rabbits(96 femoral head necrosis) were randomly divided into 4groups:Group A,control group with12 rabbits,24 femoral head necrosis;Group B,treated with rhBMP-2/PLCA implantation after core depression,with 12 rabbits,24 femoral head necrosis;Group C,treated with rhBMP-2 implantation after core depression,with 12 rabbits,24 femoral head necrosis;Croup D treated with core depression group without implantation,with 12 rabbits,24 femoral head *** animals were sacrificed after 12 *** ability of repairing bone defect was evaluated by X-ray *** mineral density analysis of the defect regions were used to evaluate the level of *** morphologic change and bone formation was assessed by HE *** angiogenesis was evaluated by VEGF ***:The osteogenetic ability and quality of femoral head necrosis in group B were better than those of other groups after 12 weeks by X-ray radiograph and morphologic *** the angiogenesis in group B was better than other *** C had similar osteogenetic quality of femoral head necrosis and angiogenesis with group ***:The treatment of rhBMP-2/PLCA implantation after core depression can promote the repair of rabbit femoral head *** is a promising and efficient synthetic bone material to treat the femoral head necrosis.

关键词： rhBMP-2 Microsphere Core decompression Femoral head necrosis

A New Method for Monitoring Scattered Stray Light of an Inner-occulted Coronagraph

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Research in Astronomy and Astrophysics 2024年第2期24卷 216-227页

作者： Da-Yang Liu hong-xin zhang Ming-Zhe Sun Zheng-Hua Huang Li-Dong Xia Wei-xin Liu Hui Fu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

The scattered stray light of a coronagraph is a type of stray light that is generated by the objective lens as its surface defects are irradiated by *** defects mainly include dust and blemishes on the lens surface,microroughness of the lens surface,and impurity and inhomogeneity of the *** the other types of relatively stable defects introduced when the objective lens is being manufactured,the scattered stray light caused by dusts on the lens surface is difficult to quantify accurately due to the disorder and randomness of the dust *** contribution of this type of stray light to the overall stray light level is difficult to determine through simulations and *** can result in continuous deterioration of the stray light level of a coronagraph and thus affect the observation capabilities of the *** solve this issue,through analyzing the forming mechanism of scattered stray light and ghost image generated by the inner-occulted coronagraph,we propose a novel method to monitor the scattered stray light from dusts by utilizing different stray light correlation *** this method,we first simulate and measure the level of stray light from the ghost image of the objective lens,and then determine the flux ratio of scattered light and ghost image on the conjugate *** the flux ratio varies with the accumulation of dusts on the lens surface,it remains constant on the image ***,the level of dust scattering light on the image plane can be obtained by using this ratio together with the level of ghost image stray *** accuracy of this method has been validated in a laboratory by applying the objective lens with numerous surface cleanliness levels.

关键词： Sun corona-Sun atmosphere-instrumentation miscellaneous-methods analytical-techniques image processing

Transarterial chemoembolization combined with radiofrequency ablation in the treatment of hepatocellular carcinomas larger than 5 cm

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Hepatoma Research 2019年第4期5卷 33-41页

作者： Yi Yang Zhuo-Min Lv Min Yan hong-xin zhang Yong Long Wei-Lu zhang Department of Pain Treatment Tangdu Hospital of the Fourth Military Medical UniversityXi’an 710038China Department of Epidemiology Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environmentthe Fourth Military Medical UniversityXi’an 710032China

Aim:This meta-analysis was designed to compare the effectiveness of the combination of transarterial chemoembolization(TACE)and radiofrequency ablation(RFA)*** of TACE alone in hepatocellular carcinoma(HCC)tumors larger than 5 ***:PUBMED,CNKI,and CBM were searched for all related randomized controlled trials(RCTs)up until October 22,*** studies were identified that compared TACE with *** alone for HCC *** response rate,the proportion of patients with either complete or partial shrinkage of tumors,and survival rate were the major evaluation ***:Meta-analysis data revealed that TACE with RFA showed significantly better tumor response rate(risk ratio(RR)=1.452,95%confidence interval(CI):1.308-1.610,P<0.001)and 1-year overall survival rate(RR=1.412,95%CI:1.249-1.596,P<0.001)than that of TACE alone ***:The data of our study indicates that TACE combined with RFA in the treatment of HCC larger than 5 cm is an effective comprehensive interventional therapy.

关键词： Transarterial chemoembolization radiofrequency ablation hepatocellular carcinoma meta-analysis

A Mild and Efficient Deprotection of Geminal Diacetates Catalyzed by FeCl3 ·6H2O in Ionic Liquid

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有机化学 2003年第Z1期23卷 107-108页

作者： GUO Hai-Ming NIU hong-Ying zhang xin-Ying WANG Jian-Ji School of Chemical and Environmental Sciences Key Laboratory of Environmental Science and Engineering for Colleges and Universities of Henan Province Henan Normal University Xinxiang 453002 School of Chemical and Environmental Sciences Key Laboratory of Environmental Science and Engineering for Colleges and Universities of Henan Province Henan Normal University Xinxiang 453002 School of Chemical and Environmental Sciences Key Laboratory of Environmental Science and Engineering for Colleges and Universities of Henan Province Henan Normal University Xinxiang 453002 School of Chemical and Environmental Sciences Key Laboratory of Environmental Science and Engineering for Colleges and Universities of Henan Province Henan Normal University Xinxiang 453002

　　The selective deprotection of geminal diacetates promoted by FeCl3·6H2O in the ionic liquid [bmim] [BF4] canbe efficiently achieved in good yields. The ionic liquid and the catalyst can be recycled easily and the... 详细信息

关键词： ionic liquid

Variability of Young Stellar Objects in the Perseus Molecular Cloud

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Research in Astronomy and Astrophysics 2023年第7期23卷 174-196页

作者： Xiao-Long Wang Min Fang Gregory J.Herczeg Yu Gao Hai-Jun Tian xing-Yu Zhou hong-xin zhang Xue-Peng Chen Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China University of Chinese Academy of Sciences Beijing 100049China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy Peking UniversityBeijing 100871China Department of Astronomy Xiamen UniversityXiamen 361005China School of Science Hangzhou Dianzi UniversityHangzhou 310018China Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

We present an analysis of 288 young stellar objects(YSOs)in the Perseus molecular cloud that have well defined g and r-band lightcurves from the Zwicky Transient *** the 288 YSOs,238 sources(83%of our working sample)are identified as variables based on the normalized peak-to-peak variability metric,with variability fraction of 92%for stars with disks and 77%for the diskless *** variables are classified into different categories using the quasiperiodicity(Q)and flux asymmetry(M)***-three variables are classified as strictly periodic objects that are well phased and can be attributed to spot modulated stellar *** also identify 22 bursters and 25 dippers,which can be attributed to accretion burst and variable extinction,*** with disks tend to have asymmetric and non-repeatable lightcurves,while the YSOs without disks tend to have(quasi)periodic *** periodic variables have the steepest change in g versus g-r,while bursters have much flatter changes than dippers in g versus *** and quasiperiodic variables display the lowest variability *** models suggest that the variability amplitudes of periodic variables correspond to changes of the spot coverage of 30%-40%,burster variables are attributed to accretion luminosity changes in the range of L_(acc)/L_(*)=0.1-0.3,and dippers are due to variable extinction with A_(V)changes in the range of 0.5-1.3 mag.

关键词： stars:variables:general stars:late-type stars:emission-line Be (stars:)starspots accretion accretion disks

Evolutionary stages and disk properties of young stellar objects in the Perseus cloud

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Research in Astronomy and Astrophysics 2015年第8期15卷 1294-1324页

作者： hong-xin zhang Yu Gao Min Fang Hai-Bo Yuan Ying-He Zhao Rui-Xiang Chang Xue-Jian Jiang Xiao-Wei Liu A-Li Luo hong-Jun Ma Zheng-Yi Shao Xiao-Long Wang National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University Chinese Academy of Sciences South America Center for Astronomy Camino EI Observatorio #1515Las CondesSantiagoChile Instituto de Astrofísica Facultad de FísicaPontificia Universidad Católica de ChileAv.Vicuna Mackenna 48607820436 MaculSantiagoChile Purple Mountain Observatory Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences Departamento de Física Teórica Universidad Autónoma de Madrid 28049 CantoblancoMadridSpain Infrared Processing and Analysis Center California Institute of TechnologyMS 100-22PasadenaCA 91125USA Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of Sciences

We investigated the evolutionary stages and disk properties of 211 young stellar objects（YSOs） across the Perseus cloud by modeling their broadband optical to mid-infrared（IR） spectral energy distribution（SED）. Our optical gri photometry data were obtained from the recently finished Purple Mountain Observatory Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center（XSTPS-GAC）.About 81% of our sample fall into the Stage II phase which is characterized by having optically thick disks, while 14% into the Stage I phase characterized by having significant infalling envelopes, and the remaining 5% into the Stage Ⅲ phase characterized by having optically thin disks. The median stellar age and mass of the Perseus YSOs are 3.1 Myr and 0.3 M⊙ respectively. By exploring the relationships among the turnoff wave bands λturnoff（longward of which significant IR excesses above the stellar photosphere are observed）, the excess spectral index αexcess as determined for λ 〉 λturnoff, and the disk inner radius Rin（determined from SED modeling） for YSOs at different evolutionary stages, we found that the median and standard deviation of αexcess for YSOs with optically thick disks tend to increase withλturnoff, especially at λturnoff ≥5.8 μm, whereas the median fractional dust luminosities Ldust/L★ tend to decrease with increasing λturnoff. This points to an inside-out process of disk clearing for small dust grains. Moreover, a positive correlation between αexcess and Rin was found at α〉excess ～ 0 and R〉in～ 10 × the dust sublimation radius Rsub, irrespective of λturnoff, Ldust/L★ and disk flaring. This suggests that the outer disk flaring either does not evolve synchronously with the inside-out disk clearing of small dust grains or has little appreciable influence on the spectral slopes at λ〈～ 24 μm. About 23% of our YSO disks are classified as transitional disks, which haveλturnoff ≥ 5.8 μm and Ldust/L★ 〉 10-3. The transitional disks and full disks occupy distinctly differe

关键词： stars: formation—stars: low-mass—stars: pre-main sequence—individual: Perseus Cloud—circumstellar matter—protoplanetary

Intracytoplasmic sperm injection in cases with a history of in vitro fertilization failure

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Asian Journal of Andrology 2003年第1期5卷 69-72页

作者： Zhi-Ling LI, hong LIN, xin-Neng zhang, Wan-Fen XIAO Reproduction Center, First Affiliated Hospital, Medical College, Shantou University, Shantou 515041, China Reproduction Center First Affiliated Hospital Medical College Shantou University Shantou 515041 China. lizhilin@***

Aim: To evaluate the effect of intracytoplasmic sperm injection (ICSI) in the management of cases with a history of conventional in vitro fertilization (IVF) failure. Methods: Two groups of patients, 19 with normal semen parameters and a history of IVF failure (metaphase Ⅱ oocytes: 0~30 %) and 28 with severe male factor infertility received ICSI technology during the same period. Ovarian stimulation was achieved by conventional procedure. Transvaginal ultrasound-guided oocyte collection was done 35~37 h after human chorionic gonadotrophin (hCG) injection. Only metaphase Ⅱ oocytes were selected for microinjection. Results: Fertilization was achieved with ICSI in all the patients. The fertilization rate (75.6 %±21.1 % vs. 73.9 %±19.2 %), cleavage rate (85.1 %±19.3 % vs. 82.7 %±22.1 %), clinical pregnancy rate per embryo transfer cycle (31.6 % vs. 28.6 %) and implantation rate per embryo (15.3 % vs. 14.4 %) did not differ significantly between the two groups. Conclusion: ICSI is a valuable method for couples with a history of IVF failure. These patients may have a similar ICSI result as in severe male infertility.

关键词： intracytoplasmic sperm injection in vitro fertilization male factor infertility fertilization failure

Quantitative Detection of Screening for Cervical Lesions with ThinPrep Cytology Test

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Clinical oncology and cancer researeh 2010年第5期7卷 299-302页

作者： hong-xin zhang Yi-min SONG Su-hong LI Yu-hui YIN Dong-ling GAO Kui-sheng CHEN Department of Pathology the First Affiliated Hospital Zhengzhou University Henan Key Laboratory for Tumor Pathology Zhengzhou 450052. Henan Province. China.

OBJECTIVE To investigate the available parameters in gynecological screening for cervical lesions by liquid-based cytology technology （ThinPrep Cytology Test, TCT） and The Bethesda System （TBS）, also with computer image analysis. METHODS With application of the image analysis system, all grades of cervical lesion cells were detected quantitatively and sorted in atypical squamous cells of undetermined significance （ASCUS）, atypical squamous cells-cannot exclude HSIL （ASC-H）, low-grade squamous intraepithelial lesion （LSIL）, high-grade squamous intraepithelial lesion （HSIL） and cervical squamous cell carcinoma （SCC） with the mean optical density （MOD）, average grey （AG）, positive units （PU）, and nucleus to cytoplasmic ratio （N： C）. Differences between each group of cells were compared and analyzed statistically. RESULTS Apart from four stereologic parameters in LSIL and HSIL groups there were no differences among them, in the other groups, there was statistically significant in differences between MOD, AG and PU values. Differences between them in the ratio of nucleus to cytoplasm were highly statistically significant. CONCLUSION Stereological indexes may serve as a screening tool for cervical lesions. The image analysis system is expected to become a new means of cytological assisted diagnosis.

关键词： cell biology uterine cervical neoplasms TBS image analysis computer-assisted.