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300 results on '"Du, Yongming"'

63. Complete salpingectomy versus tubal ligation during cesarean section: a systematic review and meta-analysis.

Author

Yang, Miao, Du, Yongming, and Hu, Yichao

Subjects
*META-analysis, *TUBAL sterilization, *SYSTEMATIC reviews, *OVARIAN reserve, *CESAREAN section, *SALPINGECTOMY
Abstract

Objective: This study aimed to evaluate the safety profile and feasibility of complete salpingectomy during cesarean delivery in women desiring permanent sterilization.Data Sources: We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials from inception to July 2018. Study Selection: studies comparing total salpingectomy with tubal ligation during cesarean deliveries were included.Results: Nine studies involving a total of 1274 participants were eligible. Our analyses showed that the total operative time was slightly longer for the bilateral salpingectomy than for the tubal ligation group (MD = 5.81, 95% CI: 0.85-10.77). Two comparison groups were comparable with regard to intraoperative complications (RR = 1.42, 95% CI: 0.65-3.11), postoperative complications (RR = 1.70, 95% CI: 0.83-3.48), estimated blood loss in total procedures, need for blood transfusion, operative complications, risk of postpartum hemorrhage, surgical site infection, ICU admission, need for presentation to hospital, short-term ovarian reserve, and completion rate of sterilization surgeries (RR = 0.90, 95% CI: 0.80-1.00).Conclusion: Complete salpingectomy slightly prolonged surgical time by a reasonable range and showed similar safety profile and greater cost-effectiveness than tubal ligation as permanent sterilization procedures at cesarean delivery. [ABSTRACT FROM AUTHOR]

Published
2021
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64. Environmental Effects of Heavy Metals from the E-Waste Dismantling Site, South China.

Author

Kong, Deguan, Du, Yongming, Luo, Min, Liu, Guowei, Su, Xiaotong, Luo, Dinggui, Huang, Xuexia, Wei, Lezhang, Liu, Yu, and Wu, Qihang

Subjects
*HEAVY metals, *ECOLOGICAL risk assessment, *ELECTRONIC waste, *HEAVY metal toxicology, *WATER hyacinth
Abstract

E-waste dismantling activities have caused serious heavy metals pollution in some parts of China. In this study, the contents of 15 metals (Ag, As, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, Rb, Sb, Sn, Tl, and Zn) in soil, sediment, and water hyacinth derived from the e-waste dismantling activities were investigated. Based on these data, the Geo-accumulation index (Igeo) and the potential ecological risk index (RI) were used to assess potential ecological risk. The results showed that the concentration of As, Cd, Cu, Sb, Sn, and Zn in soil for 6.4–131, 0.09–11.2, 25.5–5900, 3.7–443, 5.7–272, and 39–2040 mg kg−1, which the average content exceeded the natural background levels for 5.6, 57, 87, 142.7, 16.7 and 12.7 times, respectively. The concentration of Cu, Sb, Sn, and Zn in sediment for 41.2–468.3, 2.59–33.83, 10.3–92.9, and 148–502.7 mg kg−1, respectively, which the average content exceeded the natural background levels for 14.7, 20.9, 7.1, and 5.7 times, respectively. The Igeo indicated that soil and sediment at sites where e-waste was still heavily contaminated with a variety of heavy metals (such as Cd, Cu, Pb, Sb, Sn, and Zn), which were obvious accumulation effects. The RI in the surface of sediment indicated the average ecological risk of As, Cd, Co, and Cu was high risk and the total risk reached a very high risk at each sampling site. Water hyacinth has strong ability to enrich heavy metals. We suggest that the heavy metals in soil and sediment should be periodically monitored, especially Cd, Cu, Pb, Sb, Sn, and Zn. Water hyacinth can be used to monitor these heavy metals contaminated in river. The cleaning up of the soil and sediment should be a priority for any future remediation program in the study area. [ABSTRACT FROM AUTHOR]

Published
2021
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79. Co-liquefaction of lignite and biomass over Ni7W3and Ni3W7catalysts

Author

ShaoJun Wang, Songdong Yao, Du Yongming, Mengmeng Wang, and Feng Huang

Subjects
Waste management, Hydrogen, General Chemical Engineering, food and beverages, Liquefaction, Biomass, chemistry.chemical_element, Raw material, complex mixtures, Catalysis, Autoclave, Chemical engineering, Stalk, chemistry, Asphaltene
Abstract

Co-liquefaction of lignite and biomass was carried out in an autoclave by varying the biomass type and initial hydrogen pressure as well as the catalyst. The properties of the catalysts, raw materials, and residues were characterized by Ultimate analyses, BET, H2-TPR, TG/DTG, and TPO. The results showed that synergetic effect between lignite and biomass (pine shoot, corn cob, and corn stalk) might be positive, insignificant, or even negative depending on biomass type and reaction conditions. Higher hydrogenation pressure favours the formation of oil and reduction of asphaltene. Catalysts also play important roles in the performance of co-hydrogenation of lignite and biomass. Highly active catalysts (Ni3W7) may form more active hydrogen species in the solution, stabilizing smaller fragments and increasing the formation of oil.

Published
2015

92. Correlation-based temperature and emissivity separation algorithm

Author

Du Yongming, LI Xiao-wen, Xiao Qing, Cheng Jie, Liu Qinhuo, and Liu Qiang

Subjects
Correlation, Materials science, Pixel, Radiance, Emissivity, General Earth and Planetary Sciences, Equivalent temperature, Wavenumber, Hyperspectral imaging, Inversion (meteorology), Remote sensing
Abstract

Based on analyzing the relationship between the atmospheric downward radiance and surface emissivity, this paper proposes a correlation criterion to optimize surface temperature during the process of temperature and emissivity separation from thermal infrared hyperspectral data, and puts forward the correlation-based temperature and emissivity separation algorithm (CBTES). The algorithm uses the correlation between the atmospheric downward radiance and surface emissivity to optimize surface temperature, and obtains surface emissivity with this temperature. The accuracy of CBTES was evaluated by the simulated thermal infrared hyperspectral data. The simulated results show that the CBTES can achieve high accuracy of temperature and emissivity inversion. CBTES has been compared with the iterative spectrally smooth temperature/emissivity separation (ISSTES), and the comparison results show that they have relative accuracy. Besides, CBTES is insensitive to the instrumental random noise and the change of atmospheric downward radiance during the measurements. As regards the nonisothermal pixel, its radiometric temperature changes slowly with the wavenumber when its emissivity is defined as r-emissivity. The CBTES can be used to derive the equivalent temperature of nonisothermal pixel in a narrow spectral region when we assumed that the radiometric temperature is invariable in the narrow spectral region. The derived equivalent temperatures in multi-spectral regions in 714–1250 cm−1 can characterize the change trend of nonisothermal pixel’s radiometric temperature.

Published
2008

99. Evaluation of Four Kernel-Driven Models in the Thermal Infrared Band.

Author

Cao, Biao, Gastellu-Etchegorry, Jean-Philippe, Du, Yongming, Li, Hua, Bian, Zunjian, Hu, Tian, Fan, Wenjie, Xiao, Qing, and Liu, Qinhuo

Subjects
LAND surface temperature, TEMPERATURE distribution, BRIGHTNESS temperature, PHOTOSYNTHETICALLY active radiation (PAR)
Abstract

Many physical models have been proposed to simulate the directional anisotropy in the thermal infrared (TIR) region over vegetation canopies to produce angular corrected directional brightness temperature or land surface temperature. However, too many input parameters obstruct their operational use. Semiempirical kernel-driven models are designed to be a tradeoff between physical accuracy and operationality. Recently, four kernel-driven models have been proposed: the first two are direct extensions of kernel models in the visible- and near-infrared region and the last two were directly designed for the TIR region. In this paper, 153 continuous and 153 discrete canopies with varying structures and temperature distributions were considered in order to evaluate their accuracies against two physical models (4SAIL and DART). Their error distribution, scatterplots, and directional anisotropy patterns are compared. LSF-Li model, followed by Ross-Li, Vinnikov, and RL model, gave the best fitting results for all the scenes. The $R^{2}$ of all four kernel models can reach up to 0.82 for discrete scenes; however, the kernel-driven models underestimate the hotspot effect from continuous scenes; therefore, further improvements are necessary for operational use with future TIR satellite missions. [ABSTRACT FROM AUTHOR]

Published
2019
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