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Cumulative impact of dam constructions on streamflow and sediment regime in lower reaches of the Jinsha River, China

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Journal of Mountain Science 2018年第12期15卷 2752-2765页

作者： huang xiao-rong GAO Lin-yun YANG Peng-peng XI yuan-yuan State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University College of Water Resource & Hydropower Sichuan University

The cumulative effect of cascade hydropower stations on river ecological environment has been widely concerned because of the significant streamflow hydrology change induced by dam constructions. The characteristics of the change in the lower reaches of the Jinsha River, China are analyzed based on long-term(1952–2015) hydrological and sedimentological data. The averaging coefficient, reservoir regulation coefficient(RRC), incoming sediment coefficient(ISC), and sediment transport modulus(STM), which reflect the variation of streamflow and sediment regimes, are defined and calculated. The results show that the construction and regulation of reservoirs reduces flow in flood season, increases flow in dry season, significantly altering the monthly discharge regimes. These alterations also led directly to changes in the timing of extreme flows at Pingshan Station. The monthly flow records at the basin outlet are reconstructed using stepwise regression, to reduce reservoir impacts. Comparisons of observed and reconstructed monthly flows demonstrate that the previous studies overestimated the cumulative effects of cascade reservoirs on flow processes. Furthermore, this study clearly illustrates that the reduction in sediment trapping and sediment transportation capacity together lead to the sharp reduction in annual sediment yield at the Pingshan Station. The earlier constructed reservoirs have more obvious effects on the ISC and STM than the more recent reservoirs and the effect of sediment trapping is related to reservoir location, on the main stream versus tributaries.

关键词： Cascade reservoirs Cumulative effect Hydrological regime Sediment load Jinsha River

Preparation of Polylactide/Poly(ether)urethane Blends with Excellent Electro-actuated Shape Memory via Incorporating Carbon Black and Carbon Nanotubes Hybrids Fillers

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Chinese Journal of Polymer Science 2018年第10期36卷 1175-1186页

作者： yuan Wei Rui huang Peng Dong xiao-Dong Qi Qiang Fu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University

In this work, hybrid conductive fillers of carbon black （CB） and carbon nanotubes （CNTs） were introduced into polylactide （PLA）/thermoplastic poly（ether）urethane （TPU） blend （70/30 by weight） to tune the phase morphology and realize rapid electrically actuated shape memory effect （SME）. Particularly, the dispersion of conductive fillers, the phase morphology, the electrical conductivities and the shape memory properties of the composites containing CB or CB/CNTs were comparatively investigated. The results suggested that both CB and CNTs were selectively localized in TPU phase, and induced the morphological change from the sea-island structure to the co-continuous structure. The presence of CNTs resulted in a denser CB/CNTs network, which enhanced the continuity of TPU phase. Because the formed continuous TPU phase provided stronger recovery driving force, the PLA/TPU/CB/CNTs composites showed better shape recovery properties compared with the PLA/TPU/CB composites at the same CB content. Moreover, the CB and CNTs exerted a synergistic effect on enhancing the electrical conduetivities of the composites. As a result, the prepared composites exhibited excellent electrically actuated SME and the shape recovery speed was also greatly enhanced. This work demonstrated a promising strategy to achieve rapid electrically actuated SME via the addition of hybrid nanoparticles with self-networking ability in binary PLA/TPU blends over a much larger composition range.

关键词： Polymer composites Shape memory polymer Co-continuous structure Self-networking behavior Hybrid filler

Enhanced electromagnetic wave absorption properties of ZIF-67 modified polymer-derived SiCN ceramics by in situ construction of multiple heterointerfaces

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Rare Metals 2023年第5期42卷 1635-1644页

作者： Tao-Bo Geng Gao-yuan Yu Gao-Feng Shao xiao-Gu huang School of Chemistry and Materials Science Nanjing University of Information Science&TechnologyNanjing210044China

Multiphase polymer-derived ceramics have the advantages of thermal stability and adjustable dielectric properties,which exhibit significant potential for use in high-temperature microwave absorbing ***,Co-containing polymer-derived SiCN(Co-SiCN)ceramics were successfully synthesized by the physical mixing of zeolitic imidazolate framework(ZIF)-67 and polysilazane precursors and subsequent *** phase and chemical compositions,microstructures,dielectric properties,electromagnetic wave absorption(EWA)performance,and mechanism of the ceramics were *** results showed that the introduction of ZIF-67 promoted the in situ formation of dielectric loss phases,including SiC nanocrystals,CoSi nanocrystals,and free *** phase composition can be regulated by controlling the pyrolysis temperature to achieve ideal EWA *** Co-SiCN ceramic pyrolyzed at 1500℃demonstrated excellent EWA performance,with a maximum effective absorption band(EAB_(max))of 3.0 GHz at an ultralow thickness of 1.05 mm and minimum reflection loss(RL_(min))of-46.4 dB at a low frequency of 6 *** with other reported SiCN-based ceramics containing magnetic metals,the ceramics prepared in this study stand out because of their low RL and high EAB at low *** superior microwave absorption performance of the Co-SiCN ceramics is attributed to the heterointerface polarization,and impedance matching induced by the synergistic effects of their co-existing electromagnetic transparent/absorption *** study provides new insights into the development of high-performance SiCNbased microwave absorbers.

关键词： Polymer-derived SiCN ceramic Multiple heterointerfaces Zeolitic imidazolate framework(ZIF-67) Electromagnetic wave absorption(EWA)

Fitness of F1 hybrids between stacked transgenic rice T1c-19 with cry1C*/bar genes and weedy rice

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Journal of Integrative Agriculture 2019年第12期18卷 2793-2805页

作者： huang Yao WANG yuan-yuan QIANG Sheng SONG xiao-ling DAI Wei-min Weed Research Laboratory College of Life Sciences Nanjing Agricultural University

Compared to single-trait transgenic crops, stacked transgenic plants may be more prone to become weedy, and transgene flow from stacked transgenic plants to weedy relatives may pose a potential environmental risk because these hybrids could be more advantageous under specific environmental conditions. Evaluation of the potential environmental risk caused by stacked transgenes is essential for assessing the environmental consequences caused by crop-weed transgene flow. The agronomic performance of fitness-related traits was assessed in F1+(transgene positive) hybrids(using the transgenic line T1 c-19 as the paternal parent) in monoculture and mixed planting under presence or absence glufosinate pressure in the presence or absence of natural insect pressure and then compared with the performance of F1–(transgene negative) hybrids(using the non-transgenic line Minghui 63(MH63) as the paternal parent) and their weedy rice counterparts. The results demonstrated that compared with the F1– hybrids and weedy rice counterparts, the F1+ hybrid presented higher performance(P0.05) under natural insect pressure, respectively, lower performance(P0.05) in the absence of insect pressure in monoculture planting, respectively. And compared to weedy rice counterparts, the F1+ hybrid presented higher performance(P0.05) in the presence or absence of insect pressure in mixed planting, respectively. The F1+ hybrids presented nonsignificant changes(P>0.05) under the presence or absence glufosinate pressure under insect or non-insect pressure in monoculture planting. The all F1+ hybrids and two of three F1– hybrids had significantly lower(P<0.05) seed shattering than the weedy rice counterparts. The potential risk of gene flow from T1 c-19 to weedy rice should be prevented due to the greater fitness advantage of F1 hybrids in the majority of cases.

关键词： weedy rice hybrids stacked transgenes safety assessment fitness

Expressions of cellular retinoic acid binding proteins I and retinoic acid receptor-β in the guinea pig eyes with experimental myopia

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International Journal of Ophthalmology(English edition) 2011年第2期4卷 131-136页

作者： Jia huang xiao-Mei Qu and Ren-yuan Chu Department of Ophthalmology Eye and ENT Hospital Affiliated to Fudan University Shanghai 200031 China

·AIM:All-trans retinoic acid (RA) is the only extrinsic biochemical candidate known to date that could act as a growth controller,the aim of this study was to investigate the expression cellular retinoic acid binding proteins I (CRABP-I) and retinoic acid receptor-β (RAR-β) in retina of the guinea pig eyes with experimental myopia.·METHODS:Ninety guinea pigs aged 14 days were equally and randomly divided into three groups:form deprivation (FD),-5D lens,and *** diffusers for FD were white translucent hemispheres,and-5D lenses were used to introduce hyperopic *** was measured with streak retinoscopy after cycloplegia,and axial length was calculated with Cinescan A/B *** harvested at different time points were used to measure RA level with HPLC and expressions of cellular retinoic acid binding proteins I (CRABP-I) and RA receptor-β (RAR-β) were assayed with Western blot and Real-time ***13.0 software was used for statistical analysis.·RESULTS:Up-regulations of CRABP-I and RAR-β in ocular tissues correlated with changes in the refractive status and growth rate of the guinea pig eye (P <0.05).14 days of monocular form-deprivation led to-5.14D myopia and a 0.281mm axial elongation;14 days of monocular defocus produced-3.64D myopia and a 0.163 mm axial *** level of retinal RA started to elevate in 7 days (P <0.05) after visual manipulation in both FD and-5D lens groups and became more prominent by 14 days (P <0.01).The expressions of CRABP-I and RAR-β increased by 14 days after visual manipulation (P <0.05),the mRNA level of RAR-β,however,increased by 7 days after visual manipulation (P <0.05),which suggested that changes of expressions of CRABP-I and RAR-β might lag behind the change of RA.·CONCLUSION:The levels of CRABP-I and RAR-β were elevated in retina of the guinea pig eye with experimental *** the progression of experimental myopia,the retinal RA level increased rapidly,and there might be a positive

关键词： retinoic acid CRABP-I RAR-β experimental myopia guinea pig

Bioactive glass nanotube scaffold with well-ordered mesoporous structure for improved bioactivity and controlled drug delivery

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Journal of Materials Science & Technology 2019年第9期35卷 1959-1965页

作者： Jian xiao Yizao Wan Zhiwei Yang yuan huang Fanglian Yao Honglin Luo School of Materials Science and Engineering Tianjin UniversityTianjin300072China Institute of Advanced Materials School of Materials Science and EngineeringEast China Jiaotong UniversityNanchang330013China Key Laboratory of Systems Bioengineering of Ministry o f Education School o f Chemical Engineering and TechnologyTianjin UniversityTianjin300072 China

In this study, a novel mesoporous bioactive glass nanotube (MBGN) scaffold has been fabricated via template-assisted sol-gel method using bacterial cellulose (BC) as template and nonionic block copolymer (PI23) as pore-directing agent. The scaffold was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, and N2 adsorption-desorption analysis. Furthermore, simvastatin was used to evaluate the loading efficiency and release kinetics of the scaffold. The obtained scaffold displays nanofiber-like morphology, ordered mesopores on the tube walls, and interconnected three-dimensional (3D) network structure that completely replicates the BC template. In addition, it shows dual pore sizes (16.2 and 3.3 nm), large specific surface area (537.2 m^2 g^-1) and pore volume (1.429 cm^3 g^-1). More importantly, the scaffold possesses excellent apatite-forming ability and sustainable drug release as compared to the counterpart scaffold without mesopores. This unique scaffold can be considered a promising candidate for drug delivery and bone tissue regeneration.

关键词： Bioactive glass Mesopore Nanotube Bioactivity Drug delivery

The Henan extreme rainfall in July 2021: Modulation of the northward-shift monsoon trough on the synoptic-scale wave train

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Advances in Climate Change Research 2022年第6期13卷 819-825页

作者： Si-Hua huang Zhi-Ping WEN xiao-Dan CHEN yuan-yuan GUO Zhe-Wen WANG Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Institute of Eco-Chongming(IEC) Shanghai 200062China Innovation Center of Ocean and Atmosphere System Zhuhai Fudan Innovation Research InstituteZhuhai 518057China Jiangsu Collaborative Innovation Center for Climate Change Nanjing 210023China Zhumadian Meteorological Office Zhumadian 463000China

The synoptic-scale wave train is a dominant pattern of the synoptic variability over the tropical western Pacific and usually affects the extreme weather over South China and Southeast *** it could extend its influence and contribute to the Henan extreme rainfall in July 2021 still needs to be *** found that during the Henan extreme rainfall days a positively synoptic-scale vorticity disturbance dominated Henan province,China,which was embedded in the synoptic-scale wave train that originated from the western North ***,the propagating pathway of this synoptic-scale wave train located northward and was likely modulated by the latitudinal location change of the monsoon trough over the western North Pacific.A northernmost displacement of the monsoon trough in July 2021(∼23.2°N)would facilitate the synoptic-scale wave train to propagate farther northwestward via shifting the related barotropic conversion ***,the synoptic-scale wave train from the tropics could reach Henan,provide the necessary lifting forcing,and supply abundant water vapor associated with the anomalous southerly for the occurrence of Henan extreme rainfall *** results implicate that the pre-existing synoptic-scale wave train regulated by the location of the monsoon trough may be a potential precursor for heavy rainfalls in northern Central China.

关键词： Extreme rainfall Northern Central China Synoptic-scale wave train Monsoon trough Barotropic energy conversion

拉伸作用对成骨细胞粘附、铺展、粘弹性的影响

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生物物理学报 2001年第3期17卷 568-573页

作者：王红兵卢晓王远亮黄岂平秦建唐丽灵蔡绍皙重庆大学生物工程学院

采用四点弯曲梁实验装置 (自行研制 )对离体培养的大鼠成骨细胞 ,施以拉伸应变影响 ,通过微管吸吮系统、显微摄录、计算机图像系统了解细胞的粘附、铺展行为和细胞的粘弹性变化 ,认识细胞形态、粘附力及变形性对机械刺激的响应。发现 (1... 详细信息

采用四点弯曲梁实验装置 (自行研制 )对离体培养的大鼠成骨细胞 ,施以拉伸应变影响 ,通过微管吸吮系统、显微摄录、计算机图像系统了解细胞的粘附、铺展行为和细胞的粘弹性变化 ,认识细胞形态、粘附力及变形性对机械刺激的响应。发现 (1)机械拉伸2h成骨细胞与基底粘附力以及细胞单位面积粘附力较对照组明显升高 ,但加载后期与对照无明显差异 ;(2)成骨细胞粘弹性较对照组略低 ;(3)加载24h(500με)实验组细胞增殖比对照组快。机械拉伸有利于成骨细胞生长 ,并可通过粘附、铺展调整。

关键词：成骨细胞应变细胞粘附粘弹性生长铺展拉伸作用

Contrast-enhanced ultrasound predicts microvascular invasion in patients with hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2022年第6期21卷 609-613页

作者： Jing-yuan huang Zhi-Liang huang Zhe Yang xiao-Ping Zheng Department of Ultrasound Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310022China Department of Hepatobiliary and Pancreatic Surgery Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310022China Department of Pathology Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310022China

To the Editor:The presence of microvascular invasion(MVI)in hepatocellular carcinoma(HCC)is an important indicator for HCC recurrence and poor prognosis[1].Determining the preoperative MVI status is helpful for guiding clinical treatment and improving ***,MVI diagnosis is achieved primarily by postoperative histopathology,which makes it difficult to provide a definite diagnosis before ***,significant advancements in imaging technology have begun to allow clinicians to make a diagnosis of HCC MVI prior to *** this study,we used contrast-enhanced ultrasound(CEUS)to observe the characteristics of HCC enhancement patterns and quantitatively analyze the changes in HCC blood perfusion parameters to explore the value of CEUS in evaluating HCC MVI.

关键词： invasion diagnosis hepatocellular