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119篇 您的检索式:作者名="Yanfang CHEN"
    题名 作者 年代 出处 被引量
1Rural land use spatial allocation in the semiarid loess hilly area in China:Using a Particle Swarm Optimization model equipped with multi-objective optimization techniques显示文摘Semiarid loess hilly areas in China are enduring a series of environmental conflicts between urban expansion,cultivated land conservation,soil erosion and water shortage,and require land use allocation to reconcile these environmental conflicts.We argue that the optimized spatial allocation of rural land use can be achieved by a Particle Swarm Optimization (PSO) model in conjunction with multi-objective optimization techniques.Our study focuses on Yuzhong County of Gangsu Province in China,a typical catchment on the Loess Plateau,and proposes a land use spatial optimization model.The model maximizes land use suitability and spatial compactness based on a variety of constraints,e.g.optimal land use structure and restrictive areas,and employs an improved PSO algorithm equipped with a determinant initialization method and a dynamic weighted aggregation (DWA) method to obtain the optimized land use spatial pattern.The results suggest that (1) approximately 4% of land use should be reallocated and these changes would alleviate the environmental conflicts in the study area;(2) the major reshuffling is slope farmland and newly added construction and cultivated land,whereas the unchanged areas are largely forests and basic farmland;and (3) the PSO is capable of optimizing rural land use allocation,and the determinant initialization method and DWA can improve the performance of the PSO.LIU YaoLin LIU DianFeng LIU YanFang HE JianHua JIAO LiMin CHEN YiYun HONG XiaoFeng 2012Science China Earth Sciences2012,55,7:23
2Annual cost of illness of stomach and esophageal cancer patientsin urban and rural areas in China: A multi-center study显示文摘Objective: Stomach and esophageal cancer are imposing huge threats to the health of Chinese people whereas there were few studies on the financial burden of the two cancers.Methods: Costs per hospitalization of all patients with stomach or esophageal cancer discharged between September 2015 and August 2016 in seven cities/counties in China were collected, together with their demographic information and clinical details. Former patients in the same hospitals were sampled to collect information on annual direct non-medical cost, indirect costs and annual number of hospitalization. Annual direct medical cost was obtained by multiplying cost per hospitalization by annual number of hospitalization. Annual cost of illness(ACI)was obtained by adding the average value of annual direct medical cost, direct non-medical cost and indirect cost,stratified by sex, age, clinical stage, therapy and pathologic type in urban and rural areas. Costs per hospitalization were itemized into eight parts to calculate the proportion of each part. All costs were converted to 2016 US dollars(1 USD=6.6423 RMB).Results: Totally 19,986 cases were included, predominately male. Mean ages of stomach cancer and urban patients were lower than that of esophageal cancer and rural patients. ACI of stomach and esophageal cancer patients were $10,449 and $13,029 in urban areas, and $2,927 and $3,504 in rural areas, respectively. Greater ACI was associated with male, non-elderly patients as well as those who were in stage I and underwent surgeries.Western medicine fee took the largest proportion of cost per hospitalization.Conclusions: The ACI of stomach and esophageal cancer was tremendous and varied substantially among the population in China. Preferential policies of medical insurance should be designed to tackle with this burden and further reduce the health care inequalities.Zhixun Yang Hongmei Zeng Ruyi Xia Qian Liu Kexin Sun Rongshou Zheng Siwei Zhang Changfa Xia He Li Shuzheng Liu Zhiyi Zhang Yuqin Liu Guizhou Guo Guohui Song Yigong Zhu Xianghong Wu Bingbing Song Xianzhen Liao Yanfang Chen Wenqiang Wei Guihua Zhuang Wanqing Chen 2018Chinese Journal of Cancer Research2018,30,4:22
3Analysis of the Fungal Community in Apple Replanted Soil Around Bohai Gulf显示文摘Apple replant disease(ARD) is a frequently occurring plant disease in replanted orchards around Bohai Gulf, which causes growth inhibition and even death of plants. The aim of this study was to investigate the etiology of ARD around Bohai Gulf. In this study, the primary growth inhibition of apple seedlings was evaluated in ten replanted soils, sampled around Bohai Gulf. A fungal clone library was used to identify changes in the structure and composition of the soil fungal community. The results revealed that the Simpson diversity indices of Laizhou and Pulandian orchards were higher than others, presenting severe ARD. Ascomycota dominated around Bohai Gulf at the phyla level. Fusarium and Saccharomyces were abundant in all replanted soils. In addition, correlations between the relative abundance of fungal genera in soils and the severity of ARD were analyzed. The results showed that Fusarium was correlated positively with the severity of ARD, but Mortierella was negatively correlated. Furthermore, the quantitative PCR of Fusarium oxysporum, which was regarded as a factor of ARD, was performed. Overall, this study demonstrated that ARD was strongly associated with an unbalanced microbial ecosystem with more pathogenic fungi, while Fusarium in the apple replanted soil was the key factor for ARD around Bohai Gulf.WANG Gongshuai YIN Chengmiao PAN Fengbing WANG Xiaobao XIANG Li WANG Yanfang WANG Jinzheng TIAN Changping CHEN Jie MAO Zhiquan 2018Horticultural Plant Journal2018,4,5:21
4Effect of pre-deformation on the stress corrosion cracking susceptibility of aluminum alloy 2519显示文摘The effects of pre-deformation and strain rate on the stress corrosion cracking (SCC) behavior of aluminum alloy 2519 in air and in 3.5% NaCl water solution were investigated by means of slow strain rate tension (SSRT), scanning elec- tron microscopy (SEM), and transmission electron microscopy (TEM). The results indicate that the alloy is susceptible to SCC in 3.5% NaCl water solution and not in air. At the same pre-deformation, the alloy is more susceptible to SCC at 1.33 × 10·5 s·1 than at 6.66 × 10·5 s·1. Moreover, it is more susceptible to SCC at free pre-deformation than at 10% pre-deformation at the same strain rate. The number of θ precipitated along the grain boundaries is reduced and distributed discontinuously, at the same time, the precipitate-free zones (PFZ) become narrow and the susceptibility to stress corrosion cracking is reduced after 10% pre-deformation.LI Huizhong ZHANG Xinming CHEN Mingan LI Yanfang LIANG Xiaopeng 2007Rare Metals2007,26,4:15
5Risk factors and long-term health consequences of macrosomia:a prospective study in Jiangsu Province,China显示文摘We sought to determine risk factors associated with fetal macrosomia and to explore the long-term consequence of infant macrosomia at the age of 7 years.A prospective population based cohort study was designed to examine the associations between maternal and perinatal characteristics and the risk of macrosomia.A nested case-control study was conducted to explore the long-term health consequence of infant macrosomia.The mean maternal age of the macrosomia group was 24.74±3.32 years,which is slightly older than that in the control group(24.35±3.14 years,P = 0.000).The mean maternal body mass index(BMI) at early pregnancy was 22.75±2.81 kg/m 2,which was also higher than that in the control group(21.76±2.59 kg/m 2,P = 0.000).About 64.6% of macrosomic neonates were males,compared with 51.0% in the control group(P = 0.000).Compared with women with normal weight(BMI:18.5-23.9 kg/m 2),women who were overweight(BMI:24-27.9 kg/m 2) or obese(BMI ≥ 28 kg/m 2),respectively,had a 1.69-fold(P = 0.000) and a 1.49-fold(P = 0.000) increased risks of having a neonate with macrosomia,while light weight(BMI<18.5 kg/m 2) women had an approximately 50% reduction of the risk.Furthermore,macrosomia infant had a 1.52-fold and 1.50-fold risk,respectively,of developing overweight or obesity at the age of 7 years(P = 0.001 and P = 0.000).Older maternal age,higher maternal BMI at early pregnancy and male gender were independent risk factors of macrosomia.Macrosomic infant was associated with an increased predisposition to develop overweight or obesity at the beginning of their childhood.Shouyong Gu Xiaofei An Liang Fang Xiaomin Zhang Chunyan Zhang Jingling Wang Qilan Liu Yanfang Zhang Yongyue Wei Zhibin Hu Feng Chen Hongbing Shen 2012The Journal of Biomedical Research2012,26,4:14
6Targeted delivery of chlorogenic acid by mannosylated liposomes to effectively promote the polarization of TAMs for the treatment of glioblastoma显示文摘Tumor-associated macrophages(TAMs)generally display an immunosuppressive M2 phenotype and promote tumor progression and metastasis,suggesting their potential value as a target in cancer immunotherapy.Chlorogenic acid(CHA)has been identified as a potent immunomodulator that promotes the polarization of TAMs from an M2 to an M1 phenotype.However,rapid clearance in vivo and low tumor accumulation have compromised the immunotherapeutic efficacy of CHA in clinical trials.In this study,mannosylated liposomes are developed for targeted delivery of CHA to TAMs.The immunoregulatory effects of CHA,along with the overall antitumor efficacy of CHA-encapsulated mannosylated liposomes,are investigated through in vitro and in vivo experiments.The prepared CHA-encapsulated mannosylated liposomes exhibit an ideal particle size,favorable stability,and preferential accumulation in tumors via the mannose receptor-mediated TAMs-targeting effects.Further,CHA-encapsulated mannosylated liposomes inhibit G422 glioma tumor growth by efficiently promoting the polarization of the pro-tumorigenic M2 phenotype to the anti-tumorigenic M1 phenotype.Overall,these findings indicate that CHA-encapsulated mannosylated liposomes have great potential to enhance the immunotherapeutic efficacy of CHA by inducing a shift from the M2 to the M1 phenotype.Jun Ye Yanfang Yang Jing Jin Ming Ji Yue Gao Yu Feng Hongliang Wang Xiaoguang Chen Yuling Liu 2020Bioactive Materials2020,5,3:9
7Shamanskii-Like Levenberg-Marquardt Method with a New Line Search for Systems of Nonlinear Equations显示文摘To save the calculations of Jacobian,a multi-step Levenberg-Marquardt method named Shamanskii-like LM method for systems of nonlinear equations was proposed by Fa.Its convergence properties have been proved by using a trust region technique under the local error bound condition.However,the authors wonder whether the similar convergence properties are still true with standard line searches since the direction may not be a descent direction.For this purpose,the authors present a new nonmonotone m-th order Armijo type line search to guarantee the global convergence.Under the same condition as trust region case,the convergence rate also has been shown to be m+1 by using this line search technique.Numerical experiments show the new algorithm can save much running time for the large scale problems,so it is efficient and promising.CHEN Liang MA Yanfang 2020Journal of Systems Science & Complexity2020,33,5:8
8Economic Value Evaluation of Wetland Service in Yeyahu Wetland Nature Reserve,Beijing显示文摘Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-provement,biodiversity maintenance,erosion control,water supply,recreational opportunity,raw material supply and existence value.Multiple conventional evaluation methods were used to calculate the value of eight wetland services.The results showed that significant values came from biodiversity maintenance and recreational opportunity.The main reasons were as follows.Firstly,Yeyahu Wetland Nature Reserve was the habitat for migrant birds,and government had payed more efforts to protect precious birds.Secondly,the population is large in Beijing.People enjoyed going outside and enjoyed the natural and artificial wetland scenes.At the same time,most people were prepared to pay for wetland conservation.The decline of vegetation cover made the economic value of erosion control the lowest.While the shrink of water resource and the deteriorative water quality caused the economic value of water supply lower.The evaluation results could help decision-makers understand the present status of the Yeyahu Wetland Nature Reserve and provide a scientific basis for strategic decision.ZHU Lin CHEN Yun GONG Huili JIANG Weiguo ZHAO Wenji XIAO Yanfang 2011Chinese Geographical Science2011,21,6:7
9Hematopoietic stem cell-derived exosomes promote hematopoietic differentiation of mouse embryonic stem cells in vitro via inhibiting the miR126/Notch1 pathway显示文摘导出房间的 exosomes (前) 能经由他们带了的 microRNAs (米尔) 调制目标房间区别。以前的研究证明了 miR126 高度在造血的干细胞(HSC ) 被表示并且经由 modulating 在造血作用起一个作用参予祖先房间命运决定的槽口小径。在这研究,我们调查了导出 HSC 的前(HSC 前) 是否能影响老鼠的区别胚胎的干细胞(转换字符) 进 HSC。我们准备了 HSC 前 反对 ,HSC 前 sc 和 HSC 前 从控制 HSC 和 HSC transfected 与的 miR126 爬控制或 miR126 分别地模仿。HSC 前被 ultracentrifugation 孤立并且分析了使用追踪分析的 nanoparticle。我们孵化了在一个 10-d 区别正式就职时期上与老鼠转换字符收集了前,在哪个 HSC 前和槽口小径使活跃之物期间(Jagged1, 100 ng/mL ) 被加到文化每 3 d。在在转换字符的 10-d 区别时期, miR126 的表示层次, SSEA1, CD117, Sca1, Notch1 和 Hes1 被估计以后。产生 HSC 被流动 cytometry 对 HSC 标记(CD117, CD34 和 Sca1 ) 用抗体验证。我们的结果揭示了那:(1 ) 有 miR126 的 transfection 在 HSC 前 miR126 。(2 )HSC 前合作文化支持了老鼠转换字符区别进 HSC,最突出的效果在 HSC 前 miR126 合作文化。(3 ) HSC 区别被减少的 SSEA1 表示验证并且增加了 CD117 和 Sca1 表示。(4 )HSC 前引起的所有效果被 Notch1 和 Hes1 表示的重要减小伴随,这样 Notch1/Hes1 小径的抑制,而由 Jagged1 的槽口的激活废除了 HSC 前 miR126 。在结论, HSC 前由禁止 miR126/Notch1 小径在 vitro 支持老鼠转换字符的造血的区别。Feng-ling LIAO Lin TAN Hua LIU Jin-ju WANG Xiao-tang MA Bin ZHAO Yanfang CHEN Ji BIHL Yi YANG Ri-ling CHEN 2018Acta Pharmacologica Sinica2018,39,4:7
10How is mRNA expression predictive for protein expression? A correlation study on human circulating monocytes显示文摘在学习 mRNA 表示的一个关键假设是它在蛋白质表示的预言是增进知识的。然而,仅仅有限的研究在酵母探索了 mRNA 蛋白质表示关联或人的纸巾和结果是相对不一致的。我们从 30 个无关的女人在刚孤立的人的传播单核白血球在 mRNA 蛋白质表情上执行了关联分析。为 71 基因的表示蛋白质被确定并且由结合的 2-D 电气泳动识别了集体 spectrometry。相应 mRNA 表达式被 Affymetrix 基因芯片确定。重要关联(r=0.235, P < 0.0001 ) 包括所有学习基因和所有样品为整个数据集被观察。关联在基因本体论的不同生物范畴变化了。例如,最高的关联以细胞的部件为细胞外的区域的基因被完成(r=0.643, P < 0.0001 ) 并且最低关联为规定的基因被获得(r=0.099, P=0.213 ) 以生物过程。在染色体,样品的一半证明为 71 基因的重要积极关联和重要关联在所有样品在平均 mRNA 和平均蛋白质表示层次之间被发现(r=0.296, P < 0.01 ) 。在学习组水平,然而,仅仅五学习基因越过所有样品有重要积极关联。我们的结果显示出在 mRNA 和蛋白质表示层次之间的全面积极关联。然而,中等、变化的关联建议那 mRNA 表情可能有时是有用的,但是远非当然在预言蛋白质表示层次完善。Yanfang Guo Peng Xiao Shufeng Lei Feiyan Deng Gary Guishan Xiao Yaozhong Liu Xiangding Chen Liming Li Shan Wu Yuan Chen Hui Jiang Lijun Tan Jingyun Xie Xuezhen Zhu Songping Liang Hongwen Deng 2008Acta Biochimica et Biophysica Sinica2008,40,5:7
11Famitinib in combination with concurrent chemoradiotherapy in patients with locoregionally advanced nasopharyngeal carcinoma: a phase 1, open-label, dose-escalation Study显示文摘Background:Famitinib is a tyrosine kinase inhibitor against multiple targets,including vascular endothelial growth factor receptor 2/3,platelet-derived growth factor receptor,and stem cell factor receptor(c-kit).Previous studies have demonstrated anti-tumour activities of famitinib against a wide variety of advanced-stage solid cancers.We aimed to determine the safety and efficacy of famitinib with concurrent chemoradiotherapy(CCRT)in patients with locoregionally advanced nasopharyngeal carcinoma(NPC).We also evaluated the feasibility of contrast-enhanced ultrasound(D-CEUS)as a predictor of early tumour response to famitinib and to correlate functional parameters with clinical efficacy.Methods:The trial was conducted in subjects with stage III or IVa-b NPC using a 3+3 design of escalating fami-tinib doses.Briefly,subjects received 2 weeks of famitinib monotherapy followed by 7 weeks of famitinib plus CCRT.D-CEUS of the neck lymph nodes was performed at day 0,8 and 15 after famitinib was administered before starting concurrent chemoradiotherapy.End points included safety,tolerability and anti-tumour activity.Results:Twenty patients were enrolled(six each for 12.5,16.5 and 20 mg and two for 25 mg).Two patients in the 25 mg cohort developed dose-limiting toxicities,including grade 4 thrombocytopenia and grade 3 hypertension.The most common grade 3/4 adverse events were leukopenia,neutropenia and radiation mucositis.D-CEUS tests showed that more than 60%of patients achieved a perfusion parameter response after 2 weeks taking famitinib alone,and the parameter response was associated with disease improvement.In the famitinib monotherapy stage,three patients(15%)showed partial responses.The complete response rate was 65%at the completion of treatment and 95%3 months after the treatment ended.After a median follow-up of 44 months,the 3-year progression-free survival(PFS)and distant metastasis-free survival were 70%and 75%,respectively.Subjects with a decrease of perfusion parameter response,such as peak intensity decreased at least 30%after 1 week of famitinib treatment,had higher 3-year PFS(90.9%vs.44.4%,95%CI 73.7%-100%vs.11.9%-76.9%,P<0.001)than those with an increase or a reduction of less than 30%.Conclusions:The recommended famitinib dose for phase II trial is 20 mg with CCRT for patients with local advanced NPC.D-CEUS is a reliable and early measure of efficacy for famitinib therapies.Further investigation is required to confirm the effects of famitinib plus chemoradiotherapy.Qiuyan Chen Linquan Tang Na Liu Feng Han Ling Guo Shanshan Guo Jianwei Wang Huai Liu Yanfang Ye Lu Zhang Liting Liu Pan Wang Yingqin Li Qingmei He Xiaoqun Yang Qingnan Tang Yang Li YuJing Liang XueSong Sun Chuanmiao Xie Yunxian Mo Ying Guo Rui Sun Haoyuan Mo Kajia Cao Xiang Guo Musheng Zeng Haiqiang Mai Jun Ma 2018Cancer Communications2018,38,1:6
12Antigenically dominant proteins within the human liver mitochondrial proteome identified by monoclonal antibodies显示文摘Analysis of the mitochondrial proteome would provide valuable insight into the function of this important organelle, which plays key roles in energy metabolism, apoptosis, free radical production, thermogenesis, and calcium signaling. It could also increase our understanding about the mechanisms that promote mitochondrial disease. To identify proteins that are antigenically dominant in human liver mitochondria, we generated >240 hybridoma cell lines from native mitochondrial proteins after cell fusion, screening, and cloning. Antibodies that recognized mitochondrial proteins were identified by screening human liver cDNA expression libraries. In this study, we identified 6 major antigens that were recognized by at least 2 different monoclonal antibodies (mAbs). The proteins that were antigenically dominant were: acetyl-Coenzyme A acyltransferase 2 (mitochondrial 3-oxoacyl-Coenzyme A thiolase), aldehyde dehydrogenase 1 family member A1, carbamoyl phosphate synthetase 1, dihydrolipoamide S-acetyltransferase (E2 component of pyruvate dehydrogenase complex), enoyl coenzyme A hydratase 1, and hydroxysteroid (11-beta) dehydrogenase 1. We also determined the subcellular localizations of these enzymes within the mitochondria using immunohistocytochemistry. We believe that these well-characterized antibodies will provide a valuable resource for the Human Liver Proteome Project (HLPP), and will make studies aimed at investigating liver mitochondrial function far easier to perform in future. Our results provide strong evidence that, (i) depletion of dominant proteins from liver mitochondrial samples is possible and, (ii) the approaches adopted in this study can be used to explore or validate protein-protein interactions in this important organelle.JU YanFang YANG JinJu LIU Rong LIU XiaoLan DU XueMei LIU Li CHEN ZhiCheng CHI Jun LIU ShuEr GAO Yuan GAO JianEn JIAO ShunChang HE FuChu SUN QiHong 2011Science China(Life Sciences)2011,54,1:6
13Effect of current polarity on electrical sliding wear behavior of Cu-WS_2-graphite-WS_2 nanotube composites in air and vacuum conditions显示文摘In this paper Cu-WS2-graphite-WS2nanotube composites were fabricated by powder metallurgy hot pressing method.The effect of current polarity on the wear rates and contact voltage drops of the composites were investigated using a brush-on-slip ring tribometer rubbing against Cu-5 wt.%Ag alloy ring in air and vacuum,respectively.The worn surfaces of the composites were analyzed by scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS).Surface profile curves of the worn tracks were measured using the surface profiler.The results demonstrated that the current polarity has a significant effect on the wear rates and contact voltage drops of the composites in both air and vacuum conditions.Positive brush possesses a higher wear rate compared with the negative brush in the air atmosphere since the electrical field direction activates oxidation at the positive brush surface while inhibits oxidation at the negative brush surface.Except for the regular wear losses,the combined effect of molten metal bridge erosion and arc erosion cause the positive brush to lose extra material and the negative brush to gain extra material,so the positive brush shows a higher wear rate in the vacuum condition.The contact voltage drop of the positive brush is lower than that of the negative brush in the air atmosphere,but contrarily,the positive brush shows a higher contact voltage drop in the vacuum condition.QIAN Gang FENG Yi CHEN FanYan LIU WenHong ZHANG XueBin LIU YanFang 2013Science China(Technological Sciences)2013,56,11:5
14Foliar stoichiometry under different mycorrhizal types in relation to temperature and precipitation in grassland显示文摘Aims mycorrhizas play key roles in important ecosystem processes and functions.Carbon(C),nitrogen(N)and phosphorus(P)concentrations and their ratios are very important foliar traits and their cycling constrains most ecosystem processes.thus,this study addresses the influence of mycorrhizal strategies on these foliar nutrients and their response to climate change.Methods a new database was established including mycorrhizal types and leaf C_(mass),N_(mass),P_(mass),C:N and N:P of each plant species based on He et al.[(2008)leaf nitrogen:Phosphorus stoichiometry across Chinese grassland biomes.oecologia 155:301-10].the predomi-nant type of mycorrhizal association of each plant species was classified according to the published literature and our own obser-vations.We analyzed leaf C_(mass),N_(mass),P_(mass),C:N and N:P among 112 plant species in 316 samples of ascertained mycorrhizal type in the major grassland biomes of China.Important Findingsthe results show highly significant variation among different myc-orrhizal strategy types for foliar C_(mass),N_(mass) and N:P.the highest foliar C_(mass) was observed in ectotrophic mycorrhiza(ECM)type(469.8mg g1)followed by that in arbuscular mycorrhiza(AM)type(443.884 mg g1)and nonmycorrhizal(NM)type(434.0 mg g^(-1)).The foliar N concentration was significantly higher in NM type(31.0mg g^(-1)).However,the AM type had the greater C:N value(19)than the other types although less variation in C_(mass) and N:P among abuscular types on AM strategy was observed.Foliar traits showed significant variation in response to precipita-tion(mean growing season and annual precipitation(GSP and MAP))and temperature(mean growing season and annual tem-peratures(GST and MAT))depending on different mycorrhizal strategies and arbuscular types.When the responses of all folia parameters to precipitation and temperature were compared,the influence of GSP on leaf traits was greater than the influence of GST.Zhaoyong Shi Xiaogai Hou Yinglong Chen Fayuan Wangan Yanfang Miao 2013Journal of Plant Ecology2013,6,4:5
15Impact of biochar amendment on soil aggregation varied with incubation duration and biochar pyrolysis temperature显示文摘Soil aggregation is one of the crucial processes that facilitate carbon sequestration and maintain soil fertility.So far,the effect of biochar amendment on soil aggregation remains inconclusive.Here,we tested the hypothesis that the response of soil aggregation to biochar addition varied with incubation duration and biochar chemistry.A one year microcosm experiment of soil with biochar was conducted that included biochar produced at three different temperatures(300,450,and 600°C),and three biochar application rates,i.e.,0,1,and 3 wt%.It was observed that after one and three months,biochar mainly(>90%)distributed in the micro-aggregates,and slightly reduced aggregate stability and increased proportion of micro-aggregates,which was demonstrated to result from the mechanical mixture of amended biochar with soil.Contrastingly,when the duration was prolonged to six months and one year,a significant increase in macro-aggregates(6.6-38.5%)and aggregate stability(7.3-29.4%)was detected,with the increasing extent being apparently higher for low-temperature biochar.This was related to the comparatively strong interaction of biochar particles with soil minerals or microbes after long-time incubation.The strong interaction was directly supported by the significant increase in H/C,O/C ratios of isolated biochar from treated soils,the detection of typical soil mineral elements on the surface of isolated biochar,and the increase in microbial biomass carbon of treated soils.The findings of this study highlighted the role of biochar type and amendment duration in mediating the effect of biochar application on soil aggregation.Lanfang Han Biao Zhang Liying Chen Yanfang Feng Yan Yang Ke Sun 2021Biochar2021,3,3:4
16Study on Extraction Technology of Theabrownine from Liubao Tea and Its Antioxidant Activity显示文摘[Objective]This study aimed to provide theoretical reference for the extraction of theabrownine from Liubao tea,determination of the biological activity,and development and utilization of theabrownine. [Method]Orthogonal experimental design was adopted to investigate the effects of solid-liquid ratio,extraction temperature,extraction duration,and extraction frequency on the yield of theabrownine extracted from Liubao tea. The extraction technology was optimized,and the antioxidant activity of theabrownine was analyzed. [Result] The results showed that extraction frequency and extraction temperature had significant effects on the yield of theabrownine extracted from Liubao tea,while solid-liquid ratio and extraction duration had no significant effect. The optimal conditions for extracting theabrownine from Liubao tea were determined as follows: solid-liquid ratio was 1∶30,extraction temperature was 100 ℃,extraction duration was 80 min,and extraction frequency was 4 times. Under these conditions,the yield of theabrownine reached 22.92%. Results of antioxidant activity determination showed that hydroxyl radical-scavenging activity of theabrownine was as high as 74%,and the scavenging effects was significantly higher than that of Vitamin C under low concentrations; nitroso-scavenging activity of theabrownine reached 73%,with no significant difference from that of Vitamin C; superoxide anion free radical-scavenging activity of theabrownine could be above 60%,which was lower than that of Vitamin C. [Conclusion]Liubao tea contains abundant theabrownine that has relatively high antioxidant activity with good prospects in antioxidant application,which lays solid foundation for in-depth development of Liubao tea.Yingzi HE Zhaoqi LU Yanfang CHEN Yanni LIU Xiaoyan HUANG Weizhi ZHENG 2013Agricultural Biotechnology2013,2,4:4
17数字减影脑血管造影术对伴发眩晕的后循环缺血患者血管异常病因分析显示文摘目的通过数字减影脑血管造影术(DSA)对伴发眩晕的后循环缺血(PCI)患者的头颈部血管进行检查,分析其血管异常病因,掌握其发病规律。方法对138例伴发眩晕的PCI患者入院后给予详细的影像学检查,包括MRI、DSA,分析患者血管异常与PCI的因果关系。结果 138例患者,诊断为椎基底动脉系统短暂性缺血发作者89例、椎基底动脉系统脑梗死49例,综合所有的影像学检查结果分析,椎基底动脉血管异常者86例,考虑与PCI病因有关,有12例患者明确有心脏病心房颤动,考虑与后循环脑梗死病因有关,其余40例患者病因不明确。结论伴发眩晕的PCI患者的血管异常病因为:①椎基底动脉系统血管变异;②椎基底动脉系统血管狭窄或闭塞导致的后循环出现低灌注状态或脑梗死。胡沛霖 陈树波 王文胜 李喜朋 周建峰 胡岩芳 HU Peilin CHEN Shubo,WANG Wensheng LI Xipeng,ZHOU Jian feng HU Yanfang 2012临床荟萃2012,27,6:4
18Ginger polysaccharide UGP1 suppressed human colon cancer growth via p53,Bax/Bcl-2,caspase-3 pathways and immunomodulation显示文摘In previous study,we got a purified ginger polysaccharide UGP1 and verified its significant antitumor activities on colon cancer HCT116 cells.In this article,we aimed to illustrate the underlying mechanism of UGP1 exerted antitumor activities on colon cancer by using in vitro cell models and in vivo animal models.The results demonstrated that UGP1 could induce S-phase cell cycle arrest,up-regulate the expression of Bax and p53,down-regulate the expression of Bcl-2,and activate the downstream protein caspase-9 and caspase-3,which was related to intrinsic apoptosis pathway on HCT116 cells.Moreover,UGP1 significantly stimulated RAW264.7 cell proliferation and secretion activity.Similarly,UGP1 inhibited tumor proliferation on tumor-bearing mice,increased the expression of p53 and the ratio of Bax/Bcl-2,enhanced the secretion of pro-inflammatory cytokines TNF-α,IL-2,IL-6 and decreased the secretion of pro-tumor cytokines TGF-βand b FGF in serum.In conclusion,it indicated that the UGP 1 could sup press human colon cancer growth by inducing apoptosis via the regulation of p53,caspase-3,and Bax/Bcl-2 ratio-dependent pathway and regulating immune system activity.Thi s investigation provided basic theoretical mechanism of ginger polysaccharideexerted antitumor activities,and contributed to develop a possible functional food or adjuvant agent for prevention or treatment of colon cancer.Yanfang Qian Chenying Shi Chen Cheng Dengwei Liao Junping Liu Guitang Chen 2023Food Science and Human Wellness2023,12,2:4
19Substantial transition to clean household energy mix in rural China显示文摘The household energy mix has significant impacts on human health and climate,as it contributes greatly to many health-and climate-relevant air pollutants.Compared to the well-established urban energy statistical system,the rural household energy statistical system is incomplete and is often associated with high biases.Via a nationwide investigation,this study revealed high contributions to energy supply from coal and biomass fuels in the rural household energy sector,while electricity comprised∼20%.Stacking(the use of multiple sources of energy)is significant,and the average number of energy types was 2.8 per household.Compared to 2012,the consumption of biomass and coals in 2017 decreased by 45%and 12%,respectively,while the gas consumption amount increased by 204%.Increased gas and decreased coal consumptions were mainly in cooking,while decreased biomass was in both cooking(41%)and heating(59%).The time-sharing fraction of electricity and gases(E&G)for daily cooking grew,reaching 69%in 2017,but for space heating,traditional solid fuels were still dominant,with the national average shared fraction of E&G being only 20%.The non-uniform spatial distribution and the non-linear increase in the fraction of E&G indicated challenges to achieving universal access to modern cooking energy by 2030,particularly in less-developed rural and mountainous areas.In some non-typical heating zones,the increased share of E&G for heating was significant and largely driven by income growth,but in typical heating zones,the time-sharing fraction was<5%and was not significantly increased,except in areas with policy intervention.The intervention policy not only led to dramatic increases in the clean energy fraction for heating but also accelerated the clean cooking transition.Higher income,higher education,younger age,less energy/stove stacking and smaller family size positively impacted the clean energy transition.Guofeng Shen Rui Xiong Yanlin Tian Zhihan Luo Bahabaike Jiangtulu Wenjun Meng Wei Du Jing Meng Yuanchen Chen Bing Xue Bin Wang Yonghong Duan Jia Duo Fenggui Fan Lei Huang Tianzhen Ju Fenggui Liu Shunxin Li Xianli Liu Yungui Li Mu Wang Ying Nan Bo Pan Yanfang Pan Lizhi Wang Eddy Zeng Chao Zhan Yilin Chen Huizhong Shen Hefa Cheng Shu Tao 2022National Science Review2022,9,7:4
20Assessing Suitability of Rural Settlements Using an Improved Technique for Order Preference by Similarity to Ideal Solution显示文摘Land suitability assessment is a prerequisite phase in land use planning; it guides toward optimal land use by providing information on the opportunities and constraints involved in the use of a given land area. A geographic information system-based procedure, known as rural settlement suitability evaluation(RSSE) using an improved technique for order preference by similarity to ideal solution(TOPSIS), was adopted to determine the most suitable area for constructing rural settlements in different geographical locations. Given the distribution and independence of rural settlements, a distinctive evaluation criteria system that differed from that of urban suitability was established by considering the level of rural infrastructure services as well as living and working conditions. The unpredictable mutual interference among evaluation factors has been found in practical works. An improved TOPSIS using Mahalanobis distance was applied to solve the unpredictable correlation among the criteria in a suitability evaluation. Uncertainty and sensitivity analyses obtained via Monte Carlo simulation were performed to examine the robustness of the model. Daye, a resource-based city with rapid economic development, unsatisfied rural development, and geological environmental problems caused by mining, was used as a case study. Results indicate the following findings: 1) The RSSE model using the improved TOPSIS can assess the suitability of rural settlements, and the suitability maps generated using the improved TOPSIS have higher information density than those generated using traditional TOPSIS. The robustness of the model is improved, and the uncertainty is reduced in the suitability results. 2) Highly suitable land is mainly distributed in the northeast of the study area, and the majority of which is cultivated land, thereby leading to tremendous pressure on the loss of cultivated land. 3) Lastly, 12.54% of the constructive expansion permitted zone and 8.36% of the constructive expansion conditionally permitted zone are situated in an unsuitable area, which indicates that the general planning of Daye lacks the necessary verification of suitability evaluation. Guidance is provided on the development strategy of rural settlement patches to support decision making in general land use planning.LIU Yanfang CUI Jiaxing KONG Xuesong ZENG Chen 2016Chinese Geographical Science2016,26,5:4
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