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Designing Textile Architectures for High Energy-Efficiency Human Body Sweat-and Cooling-Management 被引量:9
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作者 Kun Fu Zhi Yang +5 位作者 Yong Pei Yongxin Wang Beibei Xu yuhuang Wang Bao Yang Liangbing Hu 《Advanced Fiber Materials》 CAS 2019年第1期61-70,共10页
Thermal management of textiles requires local microclimate control over heat and wet dissipation to create a comfortable thermal-wet environment at the interface of the human body and clothing.Herein,we design a fabri... Thermal management of textiles requires local microclimate control over heat and wet dissipation to create a comfortable thermal-wet environment at the interface of the human body and clothing.Herein,we design a fabric capable of both sweat-and cooling-management using a knitted fabric featuring a bilayer structure consisting of hydrophobic polyethylene terephthalate and hydrophilic cellulose fibers to simultaneously achieve high infrared(IR)transmittance and good thermal-wet comfort.The IR transmission of this cooling textile increased by~twofold in the dry state and~eightfold in the wet state compared to conventional cotton fabric.When the porosity changes from 10 to 47%with the comparison of conventional cotton fabric and our cooling textile,the heat flux is increased from 74.4 to 152.3 W/cm^(2).The cooling effect of the cooling fabric is 105%greater than that of commercial cotton fabric,which displays a better thermal management capacity for personal cooling.This bilayer design controls fast moisture transfer from inside out and provides thermal management,demonstrating high impact not only for garments,but also for other systems requiring heat regulation,such as buildings,which could mitigate energy demand and ultimately contribute to the relief of global energy and climate issues. 展开更多
关键词 Thermal responsive textile IR transmission Cooling textiles Moisture transfer and management
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Perfecting and extending the near-infrared imaging window 被引量:7
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作者 Zhe Feng Tao Tang +12 位作者 Tianxiang Wu Xiaoming Yu yuhuang Zhang Meng Wang Junyan Zheng Yanyun Ying Siyi Chen Jing Zhou Xiaoxiao Fan Dan Zhang Shengliang Li Mingxi Zhang Jun Qian 《Light(Science & Applications)》 SCIE EI CAS CSCD 2021年第10期1949-1966,共18页
In vivo fluorescence imaging in the second near-infrared window(NIR-II)has been considered as a promising technique for visualizing mammals.However,the definition of the NIR-II region and the mechanism accounting for ... In vivo fluorescence imaging in the second near-infrared window(NIR-II)has been considered as a promising technique for visualizing mammals.However,the definition of the NIR-II region and the mechanism accounting for the excellent performance still need to be perfected.Herein,we simulate the photon propagation in the NIR region(to 2340 nm),confirm the positive contribution of moderate light absorption by water in intravital imaging and perfect the NIR-II window as 900–1880 nm,where 1400–1500 and 1700–1880 nm are defined as NIR-IIx and NIR-IIc regions,respectively.Moreover,2080–2340 nm is newly proposed as the third near-infrared(NIR-III)window,which is believed to provide the best imaging quality.The wide-field fluorescence microscopy in the brain is performed around the NIRIIx region,with excellent optical sectioning strength and the largest imaging depth of intravital NIR-II fluorescence microscopy to date.We also propose 1400 nm long-pass detection in off-peak NIR-II imaging whose performance exceeds that of NIR-IIb imaging,using bright fluorophores with short emission wavelength. 展开更多
关键词 PERFECT PERFECT FIR
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Epidemiological Characteristics of Plague in the Meriones unguiculatus Plague Focus--Inner Mongolia Autonomous Region,China,1950−2019 被引量:7
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作者 Boxi Liu Dayu Zhang +9 位作者 yuhuang Chen Zhaokai He Jun Liu Dongyue Lyu Weiwei Wu Ran Duan Shuai Qin Junrong Liang Huaiqi Jing Xin Wang 《China CDC weekly》 2020年第49期935-945,共11页
From 1950 to 2019,a total of 267 plague cases in humans were reported in the Inner Mongolia Autonomous Region with 133 deaths and 10,710 Yersinia pestis isolates;21 of these cases were reported from the Meriones ungui... From 1950 to 2019,a total of 267 plague cases in humans were reported in the Inner Mongolia Autonomous Region with 133 deaths and 10,710 Yersinia pestis isolates;21 of these cases were reported from the Meriones unguiculatus(M.unguiculatus)plague focus with 6 deaths and 6,771 isolates.According to the plague situation in the Inner Mongolia Autonomous Region and the implementation of local preventive measures,the prevalence of plague in humans in the M.unguiculatus plague focus of the Inner Mongolia Autonomous Region could be divided into four stages.The first stage was the initial stage of plague prevention and control(1950–1959),with 0.80 cases annually and a case fatality rate of 37.50%.The second stage was the plague eradication stage(1960–1979),with 0.15 cases annually and a case fatality rate of 33.33%.The third stage was the plague surveillance stage(1980-1999),with 0.25 cases annually and a case fatality rate of 20.00%.The fourth stage is the comprehensive prevention and control stage under the emergency system(2000-2019),with 0.25 cases annually and a case fatality rate of 20.00%.The surveillance of rodent density(1981-2019)and studies on plague-related factors among M.unguiculatus have shown that the higher the M.unguiculatus density,the higher the nocturnal rodent capture rate(r=0.670,p<0.05)and the higher the indirect hemagglutination assay(IHA)positive rate of M.unguiculatus(r=0.344,p<0.05);the higher the percentage of hosts infected,the lower the M.unguiculatus density(r=-0.361,p<0.05)and the lower the IHA positive rate of M.unguiculatus(r=-0.337,p<0.05);the higher the percentage of nests infected with fleas,the lower the IHA positive rate of M.unguiculatus(r=-0.348,p<0.05).Together,these results suggest that it is necessary to simultaneously monitor the pathogens,serology,and vector index of M.unguiculatus to accurately reflect the plague prevalence among local animals.Although bubonic plague is the main plague type of the M.unguiculatus plague focus,severe pneumonic plague or septic plague may 展开更多
关键词 PREVENTION annually REGION
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Human scFv antibody fragments specific for hepatocellular carcinoma selected from a phage display library 被引量:3
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作者 BingYu MingNi +7 位作者 Wen-HanLi PingLei WeiXing Dai-WenXiao yuhuang Zhen-JieTang Hui-FenZhu Guan-XinShen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第26期3985-3989,共5页
AIM:To identify the scFv antibody fragments specific for hepatocellular carcinoma by biopanning from a large human naive scFv phage display library. METHODS: A large human naive scFv phage library was used to search f... AIM:To identify the scFv antibody fragments specific for hepatocellular carcinoma by biopanning from a large human naive scFv phage display library. METHODS: A large human naive scFv phage library was used to search for the specific targets by biopanning with the hepatocellular carcinoma cell line HepG2 for the positive-selecting and the normal liver cell line L02 for the counter-selecting. After three rounds of biopanning, individual scFv phages binding selectively to HepG2 cells were picked out. PCR was carried out for identification of the clones containing scFv gene sequence. The specific scFv phages were selected by ELISA and flow cytometry. DMA sequences of positive clones were analyzed by using Applied Biosystem Automated DNA sequencers 3 730. The expression proteins of the specific scFv antibody fragments in F.coli HB2151 were purified by the affinity chromatography and detected by SDS-PAGE, Western blot and ELISA. The biological effect of the soluble antibody fragments on the HepG2 cells was investigated by observing the cell proliferation. RESULTS: Two different positive clones were obtained and the functional variable sequences were identified. Their DNA sequences of the scFv antibody fragments were submitted to GenBank (accession nos: AY686498 and AY686499). The soluble scFv antibody fragments were successfully expressed in E.coli HB2151. The relative molecular mass of the expression products was about 36 ku, according to its predicted M, value. The two soluble scFv antibody fragments also had specific binding activity and obvious growth inhibition properties to HepG2 cells. CONCLUSION: The phage library biopanning permits identification of specific antibody fragments for hepatocellular carcinoma and affords experiment evidence for its immunotherapy study. 展开更多
关键词 SCFV BIOPANNING HCC IMAC Phage display
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Characteristics and quality of clinical practice guidelines for diabetic kidney disease:a systematic review
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作者 WANG yuhuang ZHANG Le +4 位作者 ZHANG Zhengshan YAO Zhi LI Xiyao SUN Luying LIAO Xing 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2024年第3期609-619,共11页
OBJECTIVE:To assess the quality of Clinical practice guidelines(CPGs)in the context of diabetic kidney disease(DKD)and determine whether any factors affect the quality.METHODS:We searched eight databases along with fi... OBJECTIVE:To assess the quality of Clinical practice guidelines(CPGs)in the context of diabetic kidney disease(DKD)and determine whether any factors affect the quality.METHODS:We searched eight databases along with five international and national organizations to develop or archive guidelines from their inception to July 2023,with an additional search of medlive.cn.And the authoritative organizations related to nephrology.CPGs and consensus statements created using direct differential diagnosis or therapy for DKD were included without language restrictions.Their quality was evaluated by four reviewers using the Appraisal of Guidelines for Research and EvaluationⅡ(AGREEⅡ)instrument.Along with the item and domain scores,the guideline was also allocated an overall quality score,which ranged from 1(lowest possible quality)to 7(highest possible quality).Moreover,an overall recommendation for use was also assigned(“recommended”,“recommended with modifications”or“not recommended”).RESULTS:A total of 16 CPGs were included,of which 14 were from Asia and the remaining two from Europe.These two CPGs were updated in the third version.Six CPGs were recommended for use because their primary domains scored in the medium or high category.Furthermore,five CPGs were recommended with modifications as the stakeholder involvement,applicability,and editorial independence domains were evaluated as low categories.In all domains,the lowest average score was for rigour of development(33%),followed by application(36%),and stakeholder involvement(51%).The highest average score was for scope and purpose(79%),followed by clarity of presentation(75%).None of the CPGs considered the patient's viewpoint,and six of 16 CPGs did not use any grading system to translate the evidence into recommendations.Additionally,only three of 16 CPGs shared search strategy,and eight of 16 CPGs did not declare a funding source.CONCLUSIONS:According to the AGREE II evaluation,more than one in four CPGs for DKD had poor methodological quality.Enhance 展开更多
关键词 diabetic nephropathies practice guideline appraisal of guidelines for research and evaluation II quality assessment systematic review
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Hot-band absorption of indocyanine green for advanced anti-stokes fluorescence bioimaging 被引量:4
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作者 Jing Zhou Xiaoxiao Fan +11 位作者 Di Wu Jie Liu yuhuang Zhang Zikang Ye Dingwei Xue Mubin He Liang Zhu Zhe Feng Andrey N.Kuzmin Wen Liu Paras N.Prasad Jun Qian 《Light(Science & Applications)》 SCIE EI CAS CSCD 2021年第10期1877-1888,共12页
Bright anti-Stokes fluorescence(ASF)in the first near-infrared spectral region(NIR-I,800 nm–900 nm)under the excitation of a 915 nm continuous wave(CW)laser,is observed in Indocyanine Green(ICG),a dye approved by the... Bright anti-Stokes fluorescence(ASF)in the first near-infrared spectral region(NIR-I,800 nm–900 nm)under the excitation of a 915 nm continuous wave(CW)laser,is observed in Indocyanine Green(ICG),a dye approved by the Food and Drug Administration for clinical use.The dependence of fluorescence intensity on excitation light power and temperature,together with fluorescence lifetime measurement,establish this ASF to be originated from absorption from a thermally excited vibrational level(hot-band absorption),as shown in our experiments,which is stronger than the upconversion fluorescence from widely-used rare-earth ion doped nanoparticles.To test the utility of this ASF NIR-I probe for advanced bioimaging,we successively apply it for biothermal sensing,cerebral blood vessel tomography and blood stream velocimetry.Moreover,in combination with L1057 nanoparticles,which absorb the ASF of ICG and emit beyond 1100 nm,these two probes generate multi-mode images in two fluorescent channels under the excitation of a single 915 nm CW laser.One channel is used to monitor two overlapping organs,urinary system&blood vessel of a live mouse,while the other shows urinary system only.Using in intraoperative real-time monitoring,such multi-mode imaging method can be beneficial for visual guiding in anatomy of the urinary system to avoid any accidental injury to the surrounding blood vessels during surgery. 展开更多
关键词 ABSORPTION EXCITATION ANATOMY
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A COLLABORATIVE SPECTRUM SENSING SCHEME USING FUZZY COMPREHENSIVE EVALUATION IN COGNITIVE RADIO 被引量:3
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作者 Yang Wendong Ye yuhuang +1 位作者 Cai Yueming Xu Youyun 《Journal of Electronics(China)》 2009年第3期326-331,共6页
Cognitive Radio(CR) is a promising technology to solve the challenging spectrum scarcity problem.However, to implement CR, spectrum sensing is the groundwork and the precondition.In this paper, a collaborative spectru... Cognitive Radio(CR) is a promising technology to solve the challenging spectrum scarcity problem.However, to implement CR, spectrum sensing is the groundwork and the precondition.In this paper, a collaborative spectrum sensing scheme using fuzzy comprehensive evaluation is proposed.The final sensing decision of the proposed scheme is based on the combination of distributed sensing results of different Secondary Users(SUs).To improve the reliability of the sensing decision, the combination procedure takes into account the credibility of each SU, which is evaluated using fuzzy comprehensive evaluation.The effect of the presence of malicious SUs and malfunctioning SUs on the performance of the proposed scheme is also investigated.The efficiency of the scheme is validated through analysis and simulation. 展开更多
关键词 Cognitive Radio (CR) Collaborative spectrum sensing Fuzzy comprehensive evaluation
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NIR-Ⅱ Excitation and NIR-I Emission Based Two-photon Fluorescence Lifetime Microscopic Imaging Using Aggregation-induced Emission Dots 被引量:3
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作者 LIU Wen ZHANG yuhuang +2 位作者 QI Jj QIAN Jun TANG Ben Zhong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2021年第1期171-176,共6页
Near-infrared(NIR)lights are powerful tools to conduct deep-tissue imaging since NIR-Ⅰ wavelengths hold less photon absorption and NIR-Ⅱ wavelengths serve low photon scattering in the biological tissues compared wit... Near-infrared(NIR)lights are powerful tools to conduct deep-tissue imaging since NIR-Ⅰ wavelengths hold less photon absorption and NIR-Ⅱ wavelengths serve low photon scattering in the biological tissues compared with visible lights.Two-photon fluorescence lifetime microscopy(2PFLM)can utilize NIR-Ⅱ excitation and NIR-Ⅰ emission at the same time with the assistance of a well-designed fluorescent agent.Aggregation induced emission(AIE)dyes are famous for unique optical properties and could serve a large two-photon absorption(2PA)cross-section as aggregated dots.Herein,we report two-photon fluorescence lifetime microscopic imaging with NIR-Ⅱ excitation and NIR-Ⅰ emission using a novel deep-red AIE dye.The AIE-gens held a 2PA cross-section as large as 1.61×10^(4)GM at 1040 nm.Prepared AIE dots had a two-photon fluorescence peak at 790 nm and a stable lifetime of 2.2 ns under the excitation of 1040 nm femtosecond laser.The brain vessels of a living mouse were vividly reconstructed with the two-photon fluorescence lifetime information obtained by our home-made 2PFLM system.Abundant vessels as small as 3.17µm were still observed with a nice signal-background ratio at the depth of 750µm.Our work will inspire more insight into the improvement of the working wavelength of fluorescent agents and traditional 2PFLM. 展开更多
关键词 NEAR-INFRARED Brain imaging Aggregation-induced emission Two-photon fluorescence lifetime microscopic imaging
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Effects of the Ratio of n-6∶n-3 Polyunsaturated Fatty Acids in the Maternal Diet on Immunoglobulins,Fatty Acid Composition,and Performance of Lactating Sows and Suckling Piglets under Conditions of Low Maternal Energy Intake 被引量:2
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作者 Wei Yao Hongliang Zhao +5 位作者 Jie Li Zhijun Wang yuhuang Han Shuren Dong Yuejiang Wang Fenglai Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS 2011年第3期141-152,共12页
This experiment was conducted to investigate the effects of different ratios of n-6 ∶ n-3 polyunsaturated fatty acids (PUFA) in sow diets on the performance of lactating sows and their piglets at low digestible ene... This experiment was conducted to investigate the effects of different ratios of n-6 ∶ n-3 polyunsaturated fatty acids (PUFA) in sow diets on the performance of lactating sows and their piglets at low digestible energy intakes. Twenty-one pregnant Landrace sows were assigned to one of three diets from day 108 of gestation until weaning (26 to 29 d) ,containing n-6∶n-3 PUFA ratios of 3 ∶1,8 ∶1 and 11 ∶1. The effects on sow and litter production traits and on sow body condition were examined. There were no differences among treatments in daily feed intakes or in changes in sow weight and back-fat levels during lactation. Litter size,litter weight at birth and weaning and litter average daily weight gain were also unaffected by treatment. As expected, large differences were observed in n-6 and n-3 fatty acids in the colostrum and plasma of sows and piglets (P 〈 0. 01) . The ratio of n6 ∶ n-3 PUFA the diet was positively correlated with those in colostrum,sow plasma and piglet plasma (R 2= 0. 55,0. 80 and 0. 80,respectively) . Sow plasma insulin and IGF-I levels at weaning were unaffected by the treatments. Plasma leptin (P 〈 0. 05) concentrations were increased in sows fed the diet with a n-6∶n-3 ratio of 8 ∶ 1. Immunoglobulin concentrations in colostrum were not altered by dietary treatment. Plasma IgG concentrations at d 14 were highest in piglets from sows fed the 8 ∶ 1 ratio of n-6∶n-3. Furthermore,this group had the highest IgA concentrations at day 21 of lactation compared with the other two groups (P 〈 0. 05) . In summary,our study demonstrated that at low digestible energy levels,altering the ratio of n-6 ∶ n-3 PUFA in the diets for lactating sows affected immune components and the fatty acid composition of lactating sows and their piglets. Further studies are needed to examine whether higher levels of fat supplementation than those used in the present study (1. 5%) can successfully enhance performance. 展开更多
关键词 fatty acid composition HORMONES IMMUNOGLOBULIN n-6∶n-3 polyunsaturated fatty acids SOWS
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EFFICIENT ANALYSIS OF ELECTROMAGNETIC RADIATION FROM MICROSTRIP ANTENNA USING VOLUME-SURFACE CURRENT CONTUNUITY METHOD
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作者 Yuan Jiade Su Kaixiong Ye yuhuang 《Journal of Electronics(China)》 2012年第6期567-571,共5页
The Volume-Surface Current Continuity Method (VSCCM) is presented to analyze electromagnetic radiation from microstrip antenna. The microstrip antenna is discretized into small triangular patches on conducting surface... The Volume-Surface Current Continuity Method (VSCCM) is presented to analyze electromagnetic radiation from microstrip antenna. The microstrip antenna is discretized into small triangular patches on conducting surface and tetrahedral volume cells in dielectric region. The Method of Moments (MoM) is applied to solve the integral equation. An equation contains the restriction relation between the volume and surface current coefficient is derived from the current continuity equation at those parts where the conducting surface is in contact with the dielectric material. A simple equivalent strip model is introduced in the treatment of the feeding probe in VSCCM. The VSCCM can reduce the unknowns required to be solved in MoM, as well as the condition number of the matrix equation. Numerical results are given to validate the accuracy and efficiency of this method. 展开更多
关键词 Method of Moments (MoM) Volume-Surface Integral Equation (VSIE) Microstrip antenna Volume-Surface Current Continuity Method (VSCCM)
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Vascular Actions of Tamoxifen and Raloxifene
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作者 yuhuang 《中国药理通讯》 2005年第1期41-42,共2页
Cardiovascular disease is among the leadingcauses of mortality worldwide. A sexrelated difference exists in the incidence of cardiovascular diseases with increased risks of cardiovascular disease such as stroke after ... Cardiovascular disease is among the leadingcauses of mortality worldwide. A sexrelated difference exists in the incidence of cardiovascular diseases with increased risks of cardiovascular disease such as stroke after menopause. Previous observational studies show significant reductions in the risk of coronary heart disease among users of hormone replacement therapy (HRT) for the primary and secondary prevention of cardiovascular disease. 展开更多
关键词 脉管作用 三苯氧胺 心血管疾病 预防作用
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中国金融形势指数混频测度及其预警行为研究 被引量:44
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作者 尚玉皇 郑挺国 《金融研究》 CSSCI 北大核心 2018年第3期21-35,共15页
金融形势指数在前瞻性政策制定、金融风险预警等方面发挥着重要作用。本文基于季度GDP及月度经济指标等信息构建了一种混频动态因子FCI模型以实现中国金融形势指数的混频测度,进而分析其风险预警功能。研究结果表明:首先,引入GDP指标的... 金融形势指数在前瞻性政策制定、金融风险预警等方面发挥着重要作用。本文基于季度GDP及月度经济指标等信息构建了一种混频动态因子FCI模型以实现中国金融形势指数的混频测度,进而分析其风险预警功能。研究结果表明:首先,引入GDP指标的混频FCI模型的测度结果优于同频模型,房地产价格、GDP等是影响金融形势指数的重要指标。其次,混频金融形势指数具有明显的顺周期特征,其与经济景气先行指数的相关性更强,但宏观经济下行时,该指数与一致指数的相关性明显增强。再次,金融形势指数是一致指数的领先因子,对宏观基本面波动趋势具有预警作用。进一步地,金融形势指数还可以明显改善景气指数的样本外预测精度。最后,替换股市及货币政策指标之后,混频FCI模型的估计结果无明显差异,金融形势指数测度结果也极为相似,从而保证了本文研究结论的稳健性。 展开更多
关键词 金融形势指数 动态因子 混频数据 经济景气指数 格兰杰因果
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基准收益率曲线与宏观经济:基于混频DSGE模型的研究 被引量:26
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作者 尚玉皇 郑挺国 王红梅 《经济研究》 CSSCI 北大核心 2018年第6期36-51,共16页
中国利率市场化的进程中,如何充分揭示基准收益率(利率)与宏观经济的相互作用机制是当前金融实践所面临的严峻挑战。为此,本文提出引入利率期限结构信息的混频DSGE模型并基于中国宏观经济展开讨论。研究结果表明:引入国债收益率曲线的... 中国利率市场化的进程中,如何充分揭示基准收益率(利率)与宏观经济的相互作用机制是当前金融实践所面临的严峻挑战。为此,本文提出引入利率期限结构信息的混频DSGE模型并基于中国宏观经济展开讨论。研究结果表明:引入国债收益率曲线的混频模型能够识别中国宏观经济的不确定性均衡现象并显著提高宏观经济分析的时效性;国债收益率作为基准收益率曲线可以合理解释中国货币政策不稳定行为的作用机制;基于前瞻性货币政策规则、BK产出缺口的稳健性检验证实了上述研究结论的可靠性,进一步说明以国债作为基准收益率能够揭示中国宏观经济运行机制,契合中国金融发展的实践过程。 展开更多
关键词 基准利率 期限结构 混频数据 DSGE模型
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混频数据信息下的时变货币政策传导行为研究——基于混频 TVP-FAVAR模型 被引量:19
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作者 尚玉皇 赵芮 董青马 《金融研究》 CSSCI 北大核心 2021年第1期13-30,共18页
现实经济环境中,货币政策操作受到金融市场及宏观经济信息的共同影响。如何基于混频大数据信息分析货币政策行为机制是需解决的现实问题。为此,本文提出一种混频时变参数因子增广向量自回归(MF-TVP-FAVAR)模型。基于宏观经济及金融市场... 现实经济环境中,货币政策操作受到金融市场及宏观经济信息的共同影响。如何基于混频大数据信息分析货币政策行为机制是需解决的现实问题。为此,本文提出一种混频时变参数因子增广向量自回归(MF-TVP-FAVAR)模型。基于宏观经济及金融市场等多维度混频数据信息的实证结果表明:首先,MF-TVP-FAVAR模型在宏观金融混频数据中提取的金融形势指数(FCI)能较好地表征宏观经济先行趋势,为货币政策的制定提供前瞻性信息。其次,混频TVP-FAVAR模型可以捕捉价格型和数量型货币政策传导的高频时变特征。与货币供应量相比,利率传导对产出的影响具有滞后性。利率传导随着利率市场化改革愈发畅通,而信贷传导机制因财政政策搭配等问题日渐受阻。再次,货币政策传导效果受到经济周期影响,无论产出效应还是价格效应,经济上行时期,货币政策传导机制都比经济衰退时期更加通畅。价格型和数量型传导机制在经济下行时的作用效果均会减弱,但数量型货币政策更易受到经济周期的影响。最后,货币政策对FCI的冲击响应具有时变性,说明金融市场信息冲击对我国货币政策调控具有结构性的动态影响。货币当局制定尤其是微调货币政策时应及时评估金融市场信息冲击的影响。 展开更多
关键词 TVP-FAVAR模型 混频数据 货币政策 传导机制
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黔西北上二叠统宣威组底部富铌多金属层地球化学特征研究 被引量:16
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作者 汪龙波 高军波 +3 位作者 杨瑞东 戴玉皇 徐海 叶琼 《地质论评》 CAS CSCD 北大核心 2020年第6期1696-1709,共14页
黔西北地区峨眉山玄武岩之上、宣威组之下广泛发育一套富铌铝土质黏土岩层,Nb含量最高可达571×10^(-6),但长期以来对铌富集的原因和形成机理研究较少。本文对威宁玉龙铌矿区富铌层位开展了矿物学和元素地球化学研究,结果表明,富铌... 黔西北地区峨眉山玄武岩之上、宣威组之下广泛发育一套富铌铝土质黏土岩层,Nb含量最高可达571×10^(-6),但长期以来对铌富集的原因和形成机理研究较少。本文对威宁玉龙铌矿区富铌层位开展了矿物学和元素地球化学研究,结果表明,富铌铝土质黏土岩与下伏峨眉山玄武岩的Nb—Ta、Zr—Hf具有明显的相关性,两者的稀土元素球粒陨石标准化配分模式图也极为相似,均表现明显的右倾,暗示富铌铝土质黏土岩很可能为峨眉山高钛玄武岩风化的产物。元素质量平衡计算显示,峨眉山玄武岩向富铌铝土质黏土岩过渡,Nb、Zr、Al明显富集,REE等元素则相对贫化。矿物学观察表明,锐钛矿很可能是富铌铝土质黏土岩中Nb的重要载体矿物,锐钛矿风化后会引起Nb的明显富集。综合各项研究,认为峨眉山玄武岩的风化是形成富铌铝土质黏土岩的关键,富铌矿物榍石、锐钛矿等经表生风化很可能是引起铝土质黏土岩中Nb明显富集的重要途径。 展开更多
关键词 黔西北 铝土质黏土岩 物质来源 富集规律
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设施番茄连作障碍土壤修复及其对青枯病害的防治效果 被引量:16
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作者 郑雪芳 刘波 +3 位作者 朱育菁 陈德局 陈小强 魏余煌 《中国生物防治学报》 CSCD 北大核心 2018年第1期117-123,共7页
连作障碍的土壤修复是世界性难题。本研究利用土壤微生态修复剂结合青枯病植物疫苗菌剂来改良土壤和预防青枯病发生。在连作7年的番茄地,设3种处理,处理1为添加量60 t/hm^2的土壤微生态修复剂和植物疫苗100倍稀释液,处理2为添加量30 t/h... 连作障碍的土壤修复是世界性难题。本研究利用土壤微生态修复剂结合青枯病植物疫苗菌剂来改良土壤和预防青枯病发生。在连作7年的番茄地,设3种处理,处理1为添加量60 t/hm^2的土壤微生态修复剂和植物疫苗100倍稀释液,处理2为添加量30 t/hm^2的土壤微生态修复剂和植物疫苗100倍稀释液,CK为不添加土壤微生态修复剂和植物疫苗,研究不同处理对连作番茄土壤养分、土壤酶活性、植株生长特性及病害防效的影响。结果表明,土壤微生态修复剂2种不同添加量处理的番茄土壤有机质、全氮、全磷和交换性钙含量均显著高于对照,而全钾含量显著低于对照;两种不同添加量处理的番茄土壤过氧化氢酶、脲酶、蔗糖酶和酸性磷酸酶活性均显著高于对照,添加量为30 t/hm^2处理的土壤各酶活性(酸性磷酸酶除外)大于添加量为60 t/hm^2处理的土壤;添加30 t/hm^2处理的单果重量(113.82 g)显著高于添加量60 t/hm^2处理(104.07 g)和对照处理(104.99 g)(P<0.05),其对番茄青枯病防效达91.87%,大于添加量为60 t/hm^2处理的防效(55.34%)。 展开更多
关键词 连作障碍 土壤修复 番茄青枯病 综合治理技术
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HIV/AIDS患者外周血中4种细胞因子IL-2、IL-4、IL-15和IL-21表达水平及其临床意义研究 被引量:13
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作者 刘琼华 刘志生 +3 位作者 郑煜煌 陈霞 贺波 郑力文 《湖南中医药大学学报》 CAS 2019年第8期1011-1014,共4页
目的观察外周血4种细胞因子(IL-2、IL-4、IL-15及IL-21)在HIV感染者/AIDS患者(HIV/AIDS)和正常人表达水平的区别及其与HIV RNA病毒载量和CD3+、CD4+细胞数量的相关性,分析其与HIV感染的关系和临床意义。方法40例未经抗病毒治疗的HIV/AID... 目的观察外周血4种细胞因子(IL-2、IL-4、IL-15及IL-21)在HIV感染者/AIDS患者(HIV/AIDS)和正常人表达水平的区别及其与HIV RNA病毒载量和CD3+、CD4+细胞数量的相关性,分析其与HIV感染的关系和临床意义。方法40例未经抗病毒治疗的HIV/AIDS和31名正常人,采用ELISA法检测外周血4种细胞因子(IL-2、IL-4、IL-15及IL-21),使用流式细胞计数法检测外周血CD3+、CD4+T淋巴细胞数量,实时聚合酶链反应测定血清中HIV RNA水平。结果未经抗病毒治疗的HIV/AIDS外周血IL-2、IL-15及IL-21水平低于正常人,而IL-4水平高于正常人(P<0.05)。CD3+、CD4+细胞数量和各细胞因子水平显示出一定的相关关系,IL-2和IL-15水平均与HIV-1 RNA载量呈负相关。结论提示外周血4种细胞因子都可能参与了HIV感染的致病机制,并与HIV RNA病毒载量及CD3+、CD4+细胞数量相关。 展开更多
关键词 人免疫缺陷病毒 艾滋病 IL-2 IL-4 IL-15 IL-21
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广东省新型冠状病毒肺炎无症状感染者流行病学特征分析 被引量:12
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作者 谢仕兰 黄建华 +8 位作者 刘珺 刘隽 龙其穗 谢莘 廖宇煌 唐玲玲 梁文佳 钟豪杰 李艳 《中华流行病学杂志》 CAS CSCD 北大核心 2020年第9期1406-1410,共5页
目的对广东省首次报告为新型冠状病毒肺炎(COVID-19)无症状感染者个案流行病学特征进行分析。方法采用追踪观察方法,对广东省2020年1月14日至3月31日首次报告为COVID-19无症状感染者的个案进行持续追踪观察,收集流行病学相关资料,分析... 目的对广东省首次报告为新型冠状病毒肺炎(COVID-19)无症状感染者个案流行病学特征进行分析。方法采用追踪观察方法,对广东省2020年1月14日至3月31日首次报告为COVID-19无症状感染者的个案进行持续追踪观察,收集流行病学相关资料,分析其流行病学特征和转归及影响因素。结果2020年1月14日至3月31日共报告325例COVID-19无症状感染者,其流行曲线与确诊病例流行曲线相似,出现两个峰,分别在1月27日至2月5日和3月17-26日。325例个案中,184例(占56.6%)后续转为确诊病例,为潜伏期无症状感染者,其年龄M为40岁,93.5%(172/184)的潜伏期无症状感染者在首次采样检测核酸阳性3 d内出现症状;141例(占43.4%)持续无症状,属于隐性感染者,占同期报告新型冠状病毒感染者的8.6%(141/1642),其年龄M为27岁,从首次采样检测阳性到出院时间M为14 d,90.8%(138/141)的隐性感染者在28 d内出院转集中隔离观察,从首次采样检测核酸阳性到末次采样检测阳性时间间隔最长73 d。隐性感染者关联的密切接触者检出阳性率为0.3%,潜伏期无症状感染者关联的密切接触者检出阳性率为2.2%。潜伏期无症状感染者和隐性感染者年龄、感染来源构成差异均有统计学意义(P<0.05)。高年龄组为首次报告为“COVID-19无症状感染者”转为确诊病例的危险因素,与0~19岁组比较,40~59岁、≥60岁均为无症状感染者转确诊的危险因素,OR值(95%CI)分别为2.730(1.380~5.402)和5.302(2.199~12.783),P值分别为0.004和0.000。境内感染无症状感染者更易转为确诊病例(OR=7.121,P=0.000)。结论新型冠状病毒感染者中存在无症状感染现象,潜伏期无症状感染者传染性可能强于隐性感染者,高年龄组、境内感染是无症状感染者转为确诊病例的危险因素,需引起关注,后续需要在人群中开展血清学调查,为防控策略制定提供依据。 展开更多
关键词 新型冠状病毒肺炎 无症状感染者 流行特征
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溶磷菌肥对红壤磷组分及土壤肥力的影响 被引量:11
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作者 郑淇元 谢意太 +8 位作者 卞海洋 文洁 刘耀辉 吴若鸿 修玉冰 朱裕煌 盛可银 兰子钧 张文元 《江西农业大学学报》 CAS CSCD 北大核心 2022年第1期233-244,共12页
【目的】施用溶磷菌肥是缓解土壤磷素累积的方式之一,对提高红壤磷素利用率有重要作用。为揭示有机肥与溶磷菌肥施用下土壤磷组分的变化,探究施加溶磷菌肥对土壤肥力的影响,为溶磷菌肥的应用提供科学指导和理论参考。【方法】设置有机... 【目的】施用溶磷菌肥是缓解土壤磷素累积的方式之一,对提高红壤磷素利用率有重要作用。为揭示有机肥与溶磷菌肥施用下土壤磷组分的变化,探究施加溶磷菌肥对土壤肥力的影响,为溶磷菌肥的应用提供科学指导和理论参考。【方法】设置有机肥、溶磷菌肥、溶磷菌+EM混合菌肥、空白对照为试验处理,采用盆栽的方法,每个处理各6盆,于结实期取样测定不同施肥处理下红壤中各形态磷的含量,红壤速效钾、铵态氮、硝态氮的含量,测定高粱生物量、株高等指标。【结果】溶磷菌肥、溶磷+EM菌混合肥、有机肥处理下,中等分解态磷的含量分别为(63.92±4.30)mg/kg、(76.62±4.97)mg/kg和(69.67±2.39)mg/kg,相比空白对照(30.38±1.77)mg/kg,3种施肥处理下中等易分解态磷含量显著提高。溶磷菌肥处理下土壤HCl-P含量为(3.62±0.53)mg/kg,较有机肥处理减少了3.1 mg/kg,说明施溶磷菌肥相比施加有机肥能够减少土壤难溶性磷的累积;溶磷菌肥处理下红壤速效钾含量为(154.90±2.37)mg/kg,相比空白处理增加55.73 mg/kg;溶磷菌肥处理下土壤铵态氮含量为(4.34±0.10)mg/kg,相比空白对照增加1.58 mg/kg,土壤硝态氮为(0.53±0.20)mg/kg,相比空白下降0.99 mg/kg,说明溶磷菌肥能够显著提高土壤速效养分,提高土壤肥力。【结论】红壤施加溶磷菌肥能够显著提高土壤的速效养分,施加溶磷菌肥、溶磷+EM菌混合肥、有机肥均能够显著影响土壤磷素结构,溶磷菌肥、溶磷+EM菌混合肥能够显著减少土壤难溶性磷素的累积,从而显著增加土壤磷素的利用效率,显著增加土壤养分,适合推广以缓解土壤磷沉积问题。 展开更多
关键词 磷组分 有效养分 溶磷菌肥 有机肥
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多烯磷脂酰胆碱联合还原型谷胱甘肽治疗酒精性肝炎效果观察 被引量:10
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作者 张余黄 殷鹏飞 《陕西医学杂志》 CAS 2019年第12期1715-1717,F0003,共4页
目的:观察多烯磷脂酰胆碱(PPC)联合还原型谷胱甘肽(G-SH)对酒精性肝炎(AH)的治疗效果。方法:选取AH患者158例,以随机数字表法将其分为对照组与联合组各79例。对照组予G-SH治疗,联合组在对照组的治疗基础上,加予PPC进行治疗,两组患者均... 目的:观察多烯磷脂酰胆碱(PPC)联合还原型谷胱甘肽(G-SH)对酒精性肝炎(AH)的治疗效果。方法:选取AH患者158例,以随机数字表法将其分为对照组与联合组各79例。对照组予G-SH治疗,联合组在对照组的治疗基础上,加予PPC进行治疗,两组患者均连续治疗4周。于治疗前、后检测所有患者血清中谷丙转氨酶(ALT)、天冬氨酸转氨酶(AST)、γ-谷氨酰转肽酶(GGT)、总胆红素(TBIL),以放射免疫法检测透明质酸(HA)和III型前胶原(PC-III)指标;并于治疗后统计两组患者的总有效率,以全数字彩色超声诊断仪检查患者肝区情况;同时观察治疗期间两组患者出现不良反应发生情况。结果:联合组患者治疗后总有效率为91.14%,明显高于对照组79.75%(χ^2=4.122,P=0.042)。两组患者治疗后ALT、AST、GGT、TBIL、HA、PC-III各指标均较治疗前明显下降(P<0.05);与对照组治疗后相比,联合组患者治疗后ALT(t=8.775,P<0.001)、AST(t=12.071,P<0.001)、GGT(t=6.695,P<0.001)、TBIL(t=9.369,P<0.001)、HA(t=11.349,P<0.001)、PC-III(t=10.612,P<0.001)水平更低。B超结果显示,联合组治疗后管道结构显示不清、肝肿大情况发生率显著低于对照组(χ^2=6.482,P=0.011;χ^2=6.661,P=0.010)。结论:采用PPC联合G-SH治疗AH优于单用G-SH,有助于患者肝功能的恢复。 展开更多
关键词 多烯磷脂酰胆碱 还原型谷胱甘肽 酒精性肝炎 肝功能 透明质酸
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