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二维剪切波弹性成像技术检测肝脾硬度早期识别乙肝肝硬化的临床研究

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中国医师杂志 2024年第4期26卷 494-498页

作者：樊韵玲杨雨辰尹豪豪沈文朱宇莉复旦大学附属中山医院超声科上海200032 上海医学影像研究所上海200032

目的评估基于二维剪切波弹性成像技术(2D-SWE)的肝脏及脾脏弹性硬度(L/S-SWE)在肝硬化患者中应用的可行性及确定早期识别肝硬化的排除界值及确诊界值。方法共纳入574例慢性乙型肝炎(简称乙肝)患者,收集入组患者的临床特征及L-SWE和S-SWE... 详细信息

目的评估基于二维剪切波弹性成像技术(2D-SWE)的肝脏及脾脏弹性硬度(L/S-SWE)在肝硬化患者中应用的可行性及确定早期识别肝硬化的排除界值及确诊界值。方法共纳入574例慢性乙型肝炎(简称乙肝)患者,收集入组患者的临床特征及L-SWE和S-SWE,分析其在肝硬化组(n=311)和非肝硬化组(n=263)中的差异。评估两组中肝脾弹性操作的成功率及稳定性。采用受试者工作特征(ROC)曲线分析L-SWE、S-SWE、天冬氨酸转氨酶与血小板比值指数(APRI)单独及其联合诊断肝硬化的效能。通过分析ROC曲线,确定排除和确诊肝硬化的双重界值。结果肝硬化组和非肝硬化组血小板及APRI差异有统计学意义(均P0.05)。进一步分析ROC曲线,L-SWE12.0 kPa时肝硬化可能性极大,介于9.4~12.0 kPa者可进一步行S-SWE检测;若S-SWE介于17.5~29.3 kPa者则归类为由2D-SWE难以界定是否有肝硬化,需进一步行肝穿刺等检查。结论2D-SWE技术在肝硬化的诊断中有较高的操作可行性,同时结合S-SWE,有助于提高早期无创识别肝硬化的诊断效能,使更多的患者避免不必要的肝穿刺检查。

关键词：肝硬化乙型肝炎弹性成像技术

高等教育与城市产业结构升级——来自新建校区和人口集聚的证据

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教育发展研究 2023年第7期43卷 11-18页

作者：林璐哈巍朱琼北京大学教育经济研究所北京100871

本文基于1999-2019年289个城市的高校新建校区与各行业从业人口规模数据,对扩招以来高等教育扩张促进城市产业结构升级的作用进行实证考察。研究发现,高校新建校区提高了城市二、三产业的从业人口密度,促进了二、三产业相对于第一产业... 详细信息

本文基于1999-2019年289个城市的高校新建校区与各行业从业人口规模数据,对扩招以来高等教育扩张促进城市产业结构升级的作用进行实证考察。研究发现,高校新建校区提高了城市二、三产业的从业人口密度,促进了二、三产业相对于第一产业的产业结构升级与第三产业内部的结构升级。三重差分结果表明,高等教育资源增加促进行业人口集聚的作用随着行业研发水平的提高而增强,验证了高等教育促进知识密集型行业人口集聚的作用。异质性分析表明,专科院校新建校区的作用大于本科院校新建校区;新建校区在东部等经济相对发达地区的作用相对较高。建议加强对高校人才留驻院校地的吸引力,积极促进高等教育在中西部和东北地区城市中推动地方产业结构升级的作用。

关键词：高等教育产业结构升级人口集聚新建校区

Phosphorus limitation on photosynthesis of two dominant understory species in a lowland tropical forest

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Journal of Plant Ecology 2014年第6期7卷 526-534页

作者： Feifei zhu Xiankai Lu Jiangming Mo Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesXingke RoadTianheGuangzhou 510650China Graduate University of the Chinese Academy of Sciences Yuquan RoadShijingshanBeijing 100049China

Aims Elevated nitrogen(N)deposition in tropical regions may accelerate ecosystem phosphorus(P)***,it is not explicitly addressed that how changes in soil N and P availability affect foliar nutrients and photosynthesis of plants in tropical *** this study,we examined the effects of N and P additions on foliar nutrients and net photosynthesis of two dominant understory species,Randia can-thioides(***)and Cryptocarya concinna(***)in an N-saturated old-growth tropical forest(>400-year-old)in south-ern *** A full factorial NP addition experiment(2×2)was established in 2007 and continued through August *** treatments,including control,N addition(150 kg N ha^(−1) year^(−1)),P addi-tion(150 kg P ha^(−1) year^(−1))and NP addition(150 kg N ha^(−1) year^(−1) plus 150 kg P ha^(−1) year^(−1))were set up in this *** traits maximum photosynthetic CO_(2) assimilation(Amax),stomatal conductance(gs),leaf transpiration(E),light satu-rating point,concentrations of chlorophyll a/b and foliar nutri-ents(N and P)of the two species were measured with standard *** Findings Three years of N addition had no significant effects on any measured photosynthetic parameter of either ***,N addition significantly elevated foliar N and P concentrations of one species(***),resulting in lower photosynthetic nitrogen use effi-ciency(PNUE).N treatments decreased foliar P concentration of the other(***),resulting in increased photosynthetic phos-phorus use efficiency,which was potentially related to N-induced P *** contrast,positive effects of P treatments on gs of ***-thioides,Amax and chlorophyll a+b of *** were observed.P treatments also elevated foliar P and PNUE of both species,imply-ing P induced more efficient use of *** results suggested a more important role of P than N on influencing photosynthetic traits of these two understory *** of P shorta

关键词： N saturation P limitation photosynthesis lowland tropical forests southern China

Microenvironment responsive nanocomposite hydrogel with NIR photothermal therapy,vascularization and anti-inflammation for diabetic infected wound healing

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Bioactive Materials 2023年第8期26卷 306-320页

作者： Shuangli zhu Bangjiao Zhao Maocai Li hao Wang Jiayi zhu Qingtao Li Huichang Gao Qi Feng Xiaodong Cao School of Materials Science and Engineering South China University of TechnologyGuangzhou510641PR China National Engineering Research Centre for Tissue Restoration and Reconstruction South China University of TechnologyGuangzhou510006PR China School of Medicine South China University of TechnologyGuangzhou510006PR China Key Laboratory of Biomedical Engineering of Guangdong Province South China University of TechnologyGuangzhou510006PR China Key Laboratory of Biomedical Materials and Engineering of the Ministry of Education South China University of TechnologyGuangzhou510006PR China Zhongshan Institute of Modern Industrial Technology of SCUT ZhongshanGuangdong528437PR China

Bacterial infection,excessive inflammation and damaging blood vessels network are the major factors to delay the healing of diabetic *** present,most of wound repair materials are passive and can’t response to the wound microenvironment,resulting in a low utilization of bioactive substances and hence a poor therapeutic ***,it’s essential to design an intelligent wound dressing responsive to the wound microenvironment to achieve the release of drugs on-demand on the basis of *** this work,metformin-laden CuPDA NPs composite hydrogel(Met@CuPDA NPs/HG)was fabricated by dynamic phenylborate bonding of gelatin modified by dopamine(Gel-DA),Cu-loaded polydopamine nanoparticles(CuPDA NPs)with hyaluronic acid modified by phenyl boronate acid(ha-PBA),which possessed good injectability,self-healing,adhesive and DPPH scavenging *** slow release of metformin was achieved by the interaction with CuPDA NPs,boric groups(B-N coordination)and the constraint of hydrogel *** had a pH and glucose responsive release behavior to treat different wound microenvironment ***,CuPDA NPs endowed the hydrogel excellent photothermal responsiveness to kill bacteria of>95%within 10 min and also the slow release of Cu^(2+)to protect wound from infection for a long ***@CuPDA NPs/HG also recruited cells to a certain direction and promoted vascularization by releasing Cu^(2+).More importantly,Met@CuPDA NPs/HG effectively decreased the inflammation by eliminating ROS and inhibiting the activation of NF-κB *** experiments demonstrated that Met@CuPDA NPs/HG significantly promoted wound healing of diabetic SD rats by killing bacteria,inhibiting inflammation,improving angiogenesis and accelerating the deposition of ECM and ***,Met@CuPDA NPs/HG had a great application potential for diabetic wound healing.

关键词： Diabetic ulcer Hydrogel dressing Cu-loaded polydopamine nanoparticles Metformin Photothermal responsiveness Angiogenesis and anti-inflammation

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聚丙烯微塑料对超滤膜过滤腐殖酸的影响

环境科学学报 2024年第5期44卷 120-127页

作者：宋亚丽赵健淇俞娅朱文芳郑磊赵青青汪华浙江科技学院土木与建筑工程学院杭州310023 浙江科技学院浙江省废弃生物质循环利用与生态处理技术重点实验室杭州310023

随着水环境中微塑料(MPs)的不断检出,以地表水为水源的饮用水处理技术面临新的挑战.当前,超滤(UF)作为净水厂常规处理的替代工艺获得了广泛应用,MPs的存在势必对超滤过程产生影响,而相关研究则鲜有报道.为深入了解MPs对超滤膜过滤天然... 详细信息

随着水环境中微塑料(MPs)的不断检出,以地表水为水源的饮用水处理技术面临新的挑战.当前,超滤(UF)作为净水厂常规处理的替代工艺获得了广泛应用,MPs的存在势必对超滤过程产生影响,而相关研究则鲜有报道.为深入了解MPs对超滤膜过滤天然有机物的影响,开展了老化前后聚丙烯(PP)MPs对超滤膜过滤腐殖酸(ha)过程的影响研究.结果表明,MPs的存在可提高ha的去除率,且老化MPs可进一步促进ha的去除.MPs可导致超滤膜膜比通量下降,但下降的幅度较小,且老化过程对膜比通量的影响更小.pH值对MPs存在下的膜比通量的影响较无MPs工况小,与Na^(+)相比,Ca^(2+)可导致超滤膜过滤MPs+ha过程的膜比通量下降更多,而MPs对超滤膜过滤ha不同亲疏水组分的膜比通量无明显影响.MPs可导致超滤膜过滤ha的膜污染阻力增加,但其值较单独过滤MPs和ha产生的膜污染阻力之和小很多,MPs与ha在膜表面共存时,MPs可吸附ha并与其在超滤膜表面形成架桥作用,使滤饼层结构松散,进而使膜污染阻力增加不多.

关键词：微塑料(MPs) 聚丙烯(PP) 腐殖酸(ha) 老化超滤膜污染

Regional Variation in Carbon Sequestration Potential of Forest Ecosystems in China

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Chinese Geographical Science 2017年第3期27卷 337-350页

作者： XU Li WEN Ding zhu Jianxing HE Nianpeng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of ScienceBeijing 100101China University of Chinese Academy of Sciences Beo'ing 10049China

Enhancing forest carbon(C) storage is recognized as one of the most economic and green approaches to offsetting anthropogenic CO_2 emissions. However, experimental evidence for C sequestration potential(C_(sp)) in China's forest ecosystems and its spatial patterns remain unclear, although a deep understanding is essential for policy-makers making decisions on reforestation. Here, we surveyed the literature from 2004 to 2014 to obtain C density data on forest ecosystems in China and used mature forests as a reference to explore C_(sp). The results showed that the C densities of vegetation and soil(0–100 cm) in China's forest ecosystems were about 69.23 Mg C/ha and 116.52 Mg C/ha, respectively. In mature forests, the C_(sp) of vegetation and soil are expected to increase to 129.26 Mg C/ha(87.1%) and 154.39 Mg C/ha(32.4%) in the coming decades, respectively. Moreover, the potential increase of C storage in vegetation(10.81 Pg C) is estimated at approximately twice that of soil(5.01 Pg C). Higher C_(sp) may occur in the subtropical humid regions and policy-makers should pay particular attention to the development of new reforestation strategies for these areas. In addition to soil nutrients and environment, climate was an important factor influencing the spatial patterns of C density in forest ecosystems in China. Interestingly, climate influenced the spatial patterns of vegetation and soil C density via different routes, having a positive effect on vegetation C density and a negative effect on soil C density. This estimation of the potential for increasing forest C storage provided new insights into the vital roles of China's forest ecosystems in future C sequestration. More importantly, our findings emphasize that climate constraints on forest C sequestration should be considered in reforestation strategies in China because the effects of climate were the opposite for spatial patterns of C density in vegetation and *** forest carbon(C) storage is recognized

关键词： carbon density forest reforestation storage sequestration potential

Co-substitution of carbonate and fluoride in hydroxyapatite： Effect on substitution type and content

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Frontiers of Materials Science 2015年第2期9卷 192-198页

作者： Qing-xia zhu Ya-Ming LI Dan haN School of Materials Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China

The nanosized hydroxyapatite substituted by fluoride and carbonate ions （CFha） had been synthesized by aqueous precipitation method. CFha had been considered as potential bone graft material for orthopedic and dental applications. The objective of this study was to determine the effects of simultaneously incorporated CO2/3- and F- on the substitution type and content. The morphologies of CFhas were observed by TEM. The carbonate substitution type and content were characterized by FTIR. The fluoride contents were determined by F-selective electrode. The phase compositions and crystallinity of the samples were investigated by XRD. The fluoride and carbonate contents of CFha increase with the dopant concentrations nonlinearly, The carbonate substitution has much more obvious effect on morphology compared with the fluoride substitution. The co-existence of CO2/3-and F- ions can influence the corresponding substitution fraction. The isomorphic substitution of sodium for calcium in the substitution process of CO2/3-can improve crystal degree and favor the B-type substitutions. Due to the closeness of the ion radii and equivalent substitution of F- and OH-, F- will occupy the OH- sites of ha crystals more easily, compelling most of the CO2/3- to be located in the B sites.

关键词： hydroxyapatite co-substitution carbonate fluoride substitution type substitution content

Multifunctional lymph-targeted platform based Mn@mSiO2 nanocomposites： Combining PFOB dual-mode imaging and DOX for cancer diagnose treatment on for and

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Nano Research 2016年第2期9卷 473-489页

作者： Tian Liu Guangyu Wu Jiejun Cheng Qing Lu Yanjie Yao Zhenjing Liu Dongchen zhu Juan Zhou Jianrong Xu Jun zhu Dannong He Country School of Materials Science and Engineering Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China National Engineering Research Center for Nanotechnology 28 East Jiang Chuan Road Shanghai 200241 China Department of Radiology Shanghai Renji Hospital Shanghai.liao Tong University School of Medicine 1630 Dong Fang Rd Shanghai 200127 China

A universal platform with M_n doping and hyaluronic acid （ha） modification, based on mesoporous silica （mSiO2）, was designed and used as a basic multifunctional material with magnetic resonance （MR） imaging. Furthermore, we added flexible functions through the addition of functional molecules. Specially, two typical compounds, hydrophobic perfluorooctyl bromide （PFOB） and hydrophilic doxorubicin （DOX）, were loaded into the channels to obtain PFOB@Mn@mSiO2@ha （PMMH） or DOX@Mn@mSiO2@ha （DMMH） or imaging and therapy, respectively. The were highly targeted to the lymph system in nanoparticles for dual-mode imaging PMMH and DMMH nanoparticles vitro and in vivo. MR and ultrasound imaging of PMMH nanoparticles were performed in the lymph system, while MR imaging and chemotherapy of DMMH nanoparticles was used to detect cancer. These results showed that both PMMH and DMMH nanoparficles can be designed with high lymph targeting efficiency. PMMH nanoparticles are a dual-mode contrast agent for both ultrasound and MR imaging for the lymph system and DMMH nanoparticles are powerful agents for the combined diagnosis and therapy of cancer in vivo.

关键词： mulfifuncfional platform dual-mode imaging magnetic resonance imaging (MRI) ultrasound imaging cancer diagnosis

Removal of humic acid from aqueous solution by cetylpyridinium bromide modified zeolite

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Journal of Environmental Sciences 2010年第9期22卷 1327-1334页

作者： Yanhui Zhan Zhiliang zhu Jianwei Lin Yanling Qiu Jianfu Zhao State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China College of Marine Science Shanghai Ocean University Shanghai 201306 China

Natural zeolite was modified by loading cetylpyridinium bromide （CPB） to create more efficient sites for humic acid （ha） adsorption. The natural and CPB modified zeolites were characterized with X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy and elemental analysis. The effects of various experimental parameters such as contact time, initial ha concentration, solution pH and coexistent Ca^2＋, upon ha adsorption onto CPB modified zeolites were evaluated. The results showed that natural zeolite had negligible affinity for ha in aqueous solutions, but CPB modified zeolites exhibited high adsorption efficiency for ha. A higher CPB loading on natural zeolites exhibited a larger ha adsorption capacity. Acidic pH and coexistent Ca^2＋ were proved to be favorable for ha adsorption onto CPB modified zeolite. The kinetic process was well described by pseudo second-order model. The experimental isotherm data fitted well to Langmuir and Sips models. The maximum monolayer adsorption capacity of CPB modified zeolite with surfactant bilayer coverage was found to be 92.0 mg/g.

关键词： modified zeolite cetylpyridinium bromide humic acid