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Numerical analysis of factors affecting the range of heat transfer in earth surrounding three subways 被引量:13
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作者 HU Zeng-hui LI xiao-zhao zhao xiao-bao xiao Lin WU Wei 《Journal of China University of Mining and Technology》 EI 2008年第1期67-71,共5页
In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When... In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning. 展开更多
关键词 earth surrounding subways range of heat transfer factors affecting heat transfer numerical analysis
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Differential diagnosis of metastasis from non-metastatic lymph nodes in cervical cancers: pilot study of diffusion weighted imaging with background suppression at 3T magnetic resonance 被引量:13
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作者 YU Shen-ping HE Li +3 位作者 LIU Bo ZHUANG xiao-zhao LIU Ming-juan HU xiao-shu 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第20期2820-2824,共5页
Background Diffusion weighted imaging with background suppression (DWIBS) is potentially useful in detecting metastatic lymph nodes. This study aimed to evaluate the efficacy of DWIBS at 3T magnetic resonance (MR)... Background Diffusion weighted imaging with background suppression (DWIBS) is potentially useful in detecting metastatic lymph nodes. This study aimed to evaluate the efficacy of DWIBS at 3T magnetic resonance (MR) for diagnosing metastatic lymph nodes in cervical cancer.Methods This retrospective study included 25 patients with cervical cancer who underwent MR examination and were treated by hysterectomy and lymphadenectomy. The metastatic and non-metastatic lymph nodes were histologically proven by operation. Apparent diffusion coefficient (ADC) values, long-axis diameters, short-axis diameters, ratio of short- to long-axis diameters of all the identifiable lymph nodes were measured and compared.Results Twenty-five primary tumor lesions, 17 metastatic lymph nodes and 140 non-metastatic lymph nodes were pathologically confirmed in 25 cases with cervical cancer. The difference of ADC values between primary tumor lesions,metastatic and non-metastatic lymph nodes were statistically significant (F=7.93, P=0.001). There was no statistically significant difference between primary tumor lesions of cervical cancer and metastatic lymph nodes (t=-0.75, P=-0.456),and the difference between primary tumor lesions and non-metastatic lymph nodes was statistically significant (t =4.68, P〈0.001). The ADC values, long-axis diameters, short-axis diameters, ratio of short- to long-axis diameters of metastatic and non-metastatic lymph nodes were (0.86±0.36)×10-3 mm2/s vs. (1.12±0.34)×10-3 mm2/s, (1.51±0.41) cm vs.(1.19±0.36) cm, (1.16±0.35) cm vs. (0.77±0.22) cm, 0.78±0.17 vs. 0.68±0.19 respectively, and statistically significant difference existed between two groups.Conclusions DWIBS at 3T MR has the distinct advantages in detecting pelvic lymph nodes of cervical cancer.Quantitative measurement of ADC values could reflect the degree of restriction of diffusion of metastatic and non-metastatic lymph nodes. The combination of size and ADC value would be useful in the accurate 展开更多
关键词 cervical cancer diffusion weighted imaging metastatic lymph node apparent diffusion coefficient
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The pathogenic spectrum of fungal keratitis in northwestern China 被引量:7
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作者 Na An Xian-Ning Liu +5 位作者 Ya-Ni Wang Juan-Li Zhu Hua Yang Jie Wu xiao-zhao Yang Xiu-Ping Zhu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第12期1846-1848,共3页
I am Na An, from the Shaanxi Key Lab of Ophthalmology, Shaanxi Institute of Ophthalmology,Xi'an City First Hospital, Xi'an, Shaanxi Province, China. Fungal keratitis is a severe problem in most developing countries.
关键词 The pathogenic spectrum of fungal keratitis in northwestern China
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Identification of Mixtures of Two Types of Body Fluids Using the Multiplex Methylation System and Random Forest Models
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作者 Han-xiao WANG xiao-zhao LIU +3 位作者 Xi-miao HE Chao xiao Dai-xin HUANG Shao-hua YI 《Current Medical Science》 SCIE CAS 2023年第5期908-918,共11页
Objective Body fluid mixtures are complex biological samples that frequently occur in crime scenes,and can provide important clues for criminal case analysis.DNA methylation assay has been applied in the identificatio... Objective Body fluid mixtures are complex biological samples that frequently occur in crime scenes,and can provide important clues for criminal case analysis.DNA methylation assay has been applied in the identification of human body fluids,and has exhibited excellent performance in predicting single-source body fluids.The present study aims to develop a methylation SNaPshot multiplex system for body fluid identification,and accurately predict the mixture samples.In addition,the value of DNA methylation in the prediction of body fluid mixtures was further explored.Methods In the present study,420 samples of body fluid mixtures and 250 samples of single body fluids were tested using an optimized multiplex methylation system.Each kind of body fluid sample presented the specific methylation profiles of the 10 markers.Results Significant differences in methylation levels were observed between the mixtures and single body fluids.For all kinds of mixtures,the Spearman’s correlation analysis revealed a significantly strong correlation between the methylation levels and component proportions(1:20,1:10,1:5,1:1,5:1,10:1 and 20:1).Two random forest classification models were trained for the prediction of mixture types and the prediction of the mixture proportion of 2 components,based on the methylation levels of 10 markers.For the mixture prediction,Model-1 presented outstanding prediction accuracy,which reached up to 99.3%in 427 training samples,and had a remarkable accuracy of 100%in 243 independent test samples.For the mixture proportion prediction,Model-2 demonstrated an excellent accuracy of 98.8%in 252 training samples,and 98.2%in 168 independent test samples.The total prediction accuracy reached 99.3%for body fluid mixtures and 98.6%for the mixture proportions.Conclusion These results indicate the excellent capability and powerful value of the multiplex methylation system in the identification of forensic body fluid mixtures. 展开更多
关键词 body fluid identification MIXTURE mixing ratio DNA methylation multiplex assay random forest model
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Red organic light-emitting diodes based photobiomodulation therapy enabling prominent hair growth
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作者 Shuang-Qiao Sun Jing-Jing Shen +11 位作者 Yu-Fei Wang Yu-Tong Jiang Lin-Fu Chen Hua Xin Jiang-Nan Wang xiao-Bo Shi xiao-zhao Zhu Qi Sun Liang-Sheng Liao Qian Chen Man-Keung Fung Shuit-Tong Lee 《Nano Research》 SCIE EI CSCD 2023年第5期7164-7170,共7页
Hair loss can cause psychological distress.Here,red organic light-emitting diode(OLED)light source is first introduced as the photobiomodulation therapy(PBMT)for hair growth and demonstrated as a promising and non-inv... Hair loss can cause psychological distress.Here,red organic light-emitting diode(OLED)light source is first introduced as the photobiomodulation therapy(PBMT)for hair growth and demonstrated as a promising and non-invasive therapeutic modality for alopecia.OLED exhibits unique advantages of homogeneous irradiation,flexible in form factor,less heat generation.These features enable OLED to be an ideal candidate for wearable PBMT light sources.A systematic study of using red OLEDs to facilitate hair growth was conducted.The results show that OLEDs excellently promote hair regrowth.OLED irradiation can increase the length of the hair by a factor of 1.5 as compared to the control,the hair regrowth area is enlarged by over 3 times after 20 days of treatments.Moreover,the mechanism of OLED that stimulates hair follicle regeneration is investigated invivo by conducting a systematic controlled experiments on mice with or without OLED PBMT.Based on the comprehensive histological and immunofluorescence staining studies,two key factors are identified for red OLEDs to facilitate hair follicle regeneration:(i)increased autophagy during the anagen phase of the hair growth cycle;(ii)increased blood oxygen content promoted by the accelerated microvascular blood flow. 展开更多
关键词 red organic light-emitting diode(OLED) light therapy hair growth AUTOPHAGY oxygen saturation
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Organizing Pneumonia in A Patient Double-Positive for ANCA and Anti-GBM Antibodies:A Case Report
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作者 Fang-Yuan Wang Xiang-Ning Yuan +8 位作者 Dan-Ni Sun Gong xiao Cheng-Huan Hu Zhong-Hua Liao Jian-Ping Ning Hui Xu Jun-Tao Feng Hong-Ling Yin xiao-zhao Li 《Chinese Medical Sciences Journal》 CAS CSCD 2023年第1期66-69,共4页
Both anti-glomerular basement membrane(GBM)disease and the anti-neutrophil cytoplasmic antibody(ANCA)-associated vasculitis(AAV)are common causes of pulmonary-renal syndrome.Organizing pneumonia(OP),a special pattern ... Both anti-glomerular basement membrane(GBM)disease and the anti-neutrophil cytoplasmic antibody(ANCA)-associated vasculitis(AAV)are common causes of pulmonary-renal syndrome.Organizing pneumonia(OP),a special pattern of interstitial lung disease,is extremely rare either in AAV or anti-GBM disease.We report an old woman presented with OP on a background of co-presentation with both ANCA and anti-GBM antibodies. 展开更多
关键词 organizing pneumonia double-positive ANCA-associated vasculitis anti-GBM antibody
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Effects of Glucocorticoid?Induced Transcript 1 Gene Deficiency on Glucocorticoid Activation in Asthmatic Mice 被引量:4
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作者 Cheng-Ping Hu Qiu-Fen Xun +4 位作者 xiao-zhao Li Xin-Yue Hu Ling Qin Ruo-Xi He Jun-Tao Feng 《Chinese Medical Journal》 SCIE CAS CSCD 2018年第23期2817-2826,共10页
Background: Glucocorticoid (GC) is the first?line therapy for asthma, but some asthmatics are insensitive to it. Glucocorticoid?induced transcript 1 gene (GLCCI1) is reported to be associated with GCs efficiency in as... Background: Glucocorticoid (GC) is the first?line therapy for asthma, but some asthmatics are insensitive to it. Glucocorticoid?induced transcript 1 gene (GLCCI1) is reported to be associated with GCs efficiency in asthmatics, while its exact mechanism remains unknown. Methods: A total of 30 asthmatic patients received fluticasone propionate for 12 weeks. Forced expiratory volume in 1 s (FEV1) and GLCCI1 expression were detected. Asthma model was constructed in wild?type and GLCCI1 knockout (GLCCI1?/?) mice. Glucocorticoid receptor (GR) and mitogen?activated protein kinase phosphatase 1 (MKP?1) expression were detected by polymerase chain reaction and Western blotting (WB). The phosphorylation of p38 mitogen?activated protein kinase (MAPK) was also detected by WB. Results: In asthmatic patients, the change of FEV1 was well positively correlated with change of GLCCI1 expression (r = 0.430, P = 0.022). In animal experiment, GR and MKP?1 mRNA levels were significantly decreased in asthmatic mice than in control mice (wild?type: GR: 0.769 vs. 1.000, P = 0.022; MKP?1: 0.493 vs. 1.000, P < 0.001. GLCCI1?/?: GR: 0.629 vs. 1.645, P < 0.001; MKP?1: 0.377 vs. 2.146, P < 0.001). Hydroprednisone treatment significantly increased GR and MKP?1 mRNA expression levels than in asthmatic groups; however, GLCCI1?/?.asthmatic mice had less improvement (wild?type: GR: 1.517 vs. 0.769, P = 0.023; MKP?1: 1.036 vs. 0.493, P = 0.003. GLCCI1?/?: GR: 0.846 vs. 0.629, P = 0.116; MKP?1: 0.475 vs. 0.377, P = 0.388). GLCCI1?/? asthmatic mice had more obvious phosphorylation of p38 MAPK than wild?type asthmatic mice (9.060 vs. 3.484, P < 0.001). It was still higher even though after hydroprednisone treatment (6.440 vs. 2.630, P < 0.001). Conclusions: GLCCI1 deficiency in asthmatic mice inhibits the activation of GR and MKP?1 and leads to more obvious phosphorylation of p38 MAPK, leading to a decremental sensitivity to GCs. 展开更多
关键词 Asthma GLUCOCORTICOID Receptor Glucocorticoid-Induced TRANSCRIPT 1 GLUCOCORTICOIDS MITOGEN-ACTIVATED Protein Kinase Phosphatase-1
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Genome-wide identification of WOX gene family in apple and a functional analysis of MdWOX4b during adventitious root formation 被引量:2
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作者 XU xiao-zhao CHE Qin-qin +2 位作者 CHENG Chen-xia YUAN Yong-bing WANG Yong-zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第5期1332-1345,共14页
The plant-specific WUSCHEL-related homeobox(WOX)genes are crucial for plant growth and development.Here,we systematically identified the MdWOX gene family in apple at the genome-wide level,and analyzed the phylogeneti... The plant-specific WUSCHEL-related homeobox(WOX)genes are crucial for plant growth and development.Here,we systematically identified the MdWOX gene family in apple at the genome-wide level,and analyzed the phylogenetic relationships,conserved motifs,gene structure,and syntenic relationships of the MdWOX genes.A total of 18 MdWOX genes were identified and phylogenetic analysis placed them into three clades.The phylogenetic relationships among the WOXs were further supported by the analyses of gene structure and conserved motifs.Chromosomal distribution and synteny analysis revealed that whole-genome and segmental duplications have played key roles in MdWOX gene family expansion.Moreover,the MdWOX genes exhibit tissue-specific expression patterns and MdWOX4a,MdWOX4b,MdWOX5b,MdWOX11/12a,and MdWOX11/12b may play essential roles in adventitious root development.The adventitious rooting ability was enhanced in MdWOX4b transgenic tobacco lines.The results of this study provide useful information for future functional studies on MdWOXs in the development of apple rootstocks. 展开更多
关键词 WOX gene APPLE adventitious root ROOTSTOCK
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线性无关非正交态的分辨 被引量:1
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作者 余少兰 周涛 +4 位作者 陈晓钊 吴小华 Shao-Lan xiao-zhao xiao-Hua 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第6期1748-1756,共9页
根据量子力学的基本原理,完美分辨非正交的量子态是不可能的.在允许无结论结果出现的情况下,广义测量(POVM)能给我们带来明确的结果.本文在现在已有的基础上,改进了广义测量的实现方法,将特殊量子态的分辨推广到更加一般的情况.
关键词 线性无关 正交态 分辨 广义测量 QUANTUM theory QUANTUM STATES 量子态 实现方法 量子力学 结果 基本原理 HOWEVER 非正交 works based 基础 改进 time POVM
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Masses and Widths of Light Scalar Mesons in Chiral Perturbation Theory
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作者 CHEN xiao-zhao LI xiao-Ya LU xiao-Fu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期451-455,共5页
Based on the diquark model, we assume that the light scalar mesons are q^2q^-2 states rather than qq^-. The chiral effective Lagrangian for the light scalar meson is constructed, and the mass relations are obtained: ... Based on the diquark model, we assume that the light scalar mesons are q^2q^-2 states rather than qq^-. The chiral effective Lagrangian for the light scalar meson is constructed, and the mass relations are obtained: the isotriplet (a0) and the isosinglet (f0) are the heaviest and are degenerate, the isodoublets (κ) are heavier and the other isosinglet (σ) is the lightest; and 2Mκ^2 = Mα0^2+ Mσ^2. Using experimental value for a0 and σ mass, we obtain Mκ=794 MeV, which is consistent with the experimental value. Then taking Г(a0^0 →ηπ^0) = 90 MeV and Г(f0→π^0π^0) = 20 MeV, we get the width of σ is: Г(σ0→π^+π^-)= 150 MeV. 展开更多
关键词 scalar meson honer diquark model chiral perturbation theory
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Global Existence and Uniqueness of Periodic Waves for a Perturbed Combined Double-Dispersive Equation
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作者 LIAO xiao-zhao HUANG Wen-tao YANG Su-min 《Chinese Quarterly Journal of Mathematics》 2022年第2期124-131,共8页
In this paper, we study the periodic wave propagation phenomenon in elastic waveguides modeled by a combined double-dispersive partial differential equation(PDE).The traveling wave ansazt transforms the PDE model into... In this paper, we study the periodic wave propagation phenomenon in elastic waveguides modeled by a combined double-dispersive partial differential equation(PDE).The traveling wave ansazt transforms the PDE model into a perturbed integrable ordinary differential equation(ODE). The global bifurcation theory is applied for the perturbed ODE model to establish the existence and uniqueness of the limit cycle, which corresponds the periodic traveling wave for the PDE model. The main tool is the Abelian integral taken from Poincaré bifurcation theory. Simulation is carried out to verify the theoretical result. 展开更多
关键词 Combined double-dispersive PDE Abelian integral Limit cycle Hamiltonian function Periodic wave
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Evaluation of casting fluidity and filling capacity of Zr-based amorphous metal melts 被引量:1
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作者 De-qiang Ma xiao-zhao Ma +3 位作者 Hong-yuan Zhang Ming-zhen Ma Xin-yu Zhang Ri-ping Liu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第11期1163-1171,共9页
Understanding the flow characteristics of amorphous metal melts is important for casting and molding processes.Fluidity of Zr-based amorphous metal melts was determined by using a self-designed apparatus.Phase analysi... Understanding the flow characteristics of amorphous metal melts is important for casting and molding processes.Fluidity of Zr-based amorphous metal melts was determined by using a self-designed apparatus.Phase analysis demonstrated that the fluidity test samples were fuUy amorphous structure.The onset crystallization temperature significantly moved toward high temperature with the increases of casting temperature,which improved the glass-forming ability and thermal stability of Zr-based amorphous metal.Fluidity test results demonstrated that the fluidity length increased monotonically with the increases of temperature,pressure,and runner diameter.By identifying the types and quantities of the defect in castings,it could conclude that smooth filling processes occurred under appropriate conditions.Experimental results indicated that the flow behavior of the Zr-based amorphous metal melts strongly depended on the casting temperature and equivalent thickness.Constitutive equation based on Newton's law of heat exchange and Rayleigh rule was established to'evaluate the fluidity of Zr-based amorphous metal melts.Theoretical calculations and experimental tests were basically coincided with each other.The determined optimal casting temperatures and equivalent thicknesses were adopted to successfully fabricate a series of fully shaped castings through gravity casting. 展开更多
关键词 Amorphous metal MELT CASTING FLUIDITY CONSTITUTIVE equation FILLING capacity
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Study on the role of magnetic resonance enterography in valuating infliximab therapy in small bowel crohn's disease
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作者 Li-Wei Dong xiao-Ning Sun +5 位作者 xiao-zhao Zhuang Fei Wang Yi-Yao Chen Zhou-TaoHe Xiang-Yang Han Cheng Lan 《Journal of Hainan Medical University》 2019年第12期16-19,共4页
Objective:To investigate the role of magnetic resonance enterography (MRE) in valuating infliximab's (IFX)curative effect in active small bowel Crohn's Disease (CD).Methods:27 patients diagnosed as active CD w... Objective:To investigate the role of magnetic resonance enterography (MRE) in valuating infliximab's (IFX)curative effect in active small bowel Crohn's Disease (CD).Methods:27 patients diagnosed as active CD were treated with IFX. Before and after the treatment, the patients were scanned with 3.0 T MRE after small intestinal preparation. The imaging characteristic was analyzed and the relevance analysis between the imaging performance and the clinical score were investigated.Results: (1) Before IFX treatment, MRE could clearly detect the intestinal wall and extra luminal lesion in active CD, including intestinal wall multiple segmental thickening and abnormal enhancement, irregular signaling, comb sign, and intestinal stricture or dilation;(2) After IFX treatment, MRE show that intestinal wall thinning and the dilated bowel lumen were improved, and the comb sign disappeared;(3) During artery phase, the signal of the intestinal lesion was improved from high signal or equal signal before the IFX treatment to equal signal or low signal after treatment (P<0.05). During vein phase, there was no significant change of lesion signal before and after treatment (P>0.05).4. the changes of imaging performance were consistant with that of the clinical score (P>0.05). Conclusions: MRE possesses clinical value in evaluating the IFX curative effect in active small bowel CD. 展开更多
关键词 Magnetic RESONANCE ENTEROGRAPHY Crhon's disease Small BOWEL INFLIXIMAB CURATIVE effect
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The effect of unilateral ureteral obstruction on the adrenal function in a rat model
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作者 LI xiao-zhao MENG Ting +1 位作者 xiao Run-sha ZHOU Qiao-ling 《中国现代医学杂志》 CAS CSCD 北大核心 2014年第24期1-4,共4页
【Objective】To explore the effect of unilateral ureteral obstruction on the adrenal function in a rat model.【Methods】36 SD rats were randomly divided into two groups:unilateral ureteral obstruction(UUO)model was em... 【Objective】To explore the effect of unilateral ureteral obstruction on the adrenal function in a rat model.【Methods】36 SD rats were randomly divided into two groups:unilateral ureteral obstruction(UUO)model was employed,and sham-operated rats were used as control.28 days after surgery,all the rats were submitted to maximum exercise tolerance test(METT),and the maximum aerobic velocity was observed.At the day 0,day 28,and after METT,the serum levels of adrenaline,noradrenaline and corticosterone in rats were detected by ELISA.【Results】1 The maximum aerobic velocity in UUO model rats was lower than that in control rats(P<0.05).2 At the beginning(day 0),there no significant difference were found in the levels of adrenaline,noradrenaline and corticosterone between two groups.3 28 days after surgery,the levels of adrenaline,noradrenaline and corticosterone in UUO model rats were slightly higher than those in control rats,but the differences were not significant(P>0.05).4After METT,the levels of adrenaline and corticosterone in UUO model rats were lower than those in control rats significantly(P<0.05).The level of noradrenaline in UUO model rats was higher than that in control rats,but there is no significant difference between two groups(P>0.05).【Conclusions】Unilateral ureteral obstruction resulted in the decrease of exercise tolerance in rats,which may contribute to the inhibition of the adrenal secretion. 展开更多
关键词 医学研究 症状 临床治疗 患者
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农村电子商务与物流配送运营服务体系建设 被引量:69
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作者 武晓钊 《中国流通经济》 CSSCI 北大核心 2016年第8期99-104,共6页
发展农村电子商务,应基于互联网和移动互联网重构地级市域范围内的农村商贸流通新体系。建设地级市区域内农村电子商务平台和农产品流通公共服务平台,进而建立全国农村电子商务平台,实现地市级、县级商品物流配送中心、乡镇商贸中心(乡... 发展农村电子商务,应基于互联网和移动互联网重构地级市域范围内的农村商贸流通新体系。建设地级市区域内农村电子商务平台和农产品流通公共服务平台,进而建立全国农村电子商务平台,实现地市级、县级商品物流配送中心、乡镇商贸中心(乡镇农贸市场)、农家店信息互通,实现内部供应链(门店、配送、县域公司总部)和外部供应链(上游供应商、生产厂商、下游客户)的信息及财务数据交换,实现农家店线上进、销、存订单管理和增值业务管理,实现对农贸流通企业、农家店经营情况的统计分析,实现网上信息服务、购销对接、在线交易、在线支付、统计分析、预警预测等功能;建设一村一店的信息化管理系统,提高村店的经营效率和数据服务能力;开发一村一品,解决农产品上行的问题,实施网上农产品期货交易,对接城乡农贸市场,同时对接地级城市的社区商超和便利店以及各种社区终端服务网店。以地级市各县为分中心的运营服务中心一方面引入电子商务服务企业合作,为农产品网上销售提供服务,另一方面开发、服务、管理乡镇服务站和村级服务点;仓储配送中心一方面用于网购商品的集中和对乡镇服务站的配送,另一方面用于分拣、包装、保鲜等农产品初加工。 展开更多
关键词 农村电商 农村物流 农民致富 农村商品流通
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伦理型领导与员工离职倾向:领导——成员交换的中介作用 被引量:25
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作者 肖贵蓉 赵衍俊 《科学学与科学技术管理》 CSSCI CSCD 北大核心 2017年第3期160-171,共12页
伦理型领导是近年来国内外理论研究与管理实践关注的焦点之一,但中国情境下伦理型领导的实证研究尚嫌不足,尤其缺乏探讨伦理型领导与员工离职倾向的作用机制。鉴于现有研究缺乏本土化量表,首先采用定性与定量相结合的方法,对中国情境下... 伦理型领导是近年来国内外理论研究与管理实践关注的焦点之一,但中国情境下伦理型领导的实证研究尚嫌不足,尤其缺乏探讨伦理型领导与员工离职倾向的作用机制。鉴于现有研究缺乏本土化量表,首先采用定性与定量相结合的方法,对中国情境下的伦理型领导量表进行修订和验证,开发包含人格特质、人际行为、激励和道德管理4个维度的新量表,继而采用该量表对422名企业员工进行大样本调查。层级回归分析结果证实:伦理型领导行为和领导—成员交换对员工离职倾向具有显著负向影响;领导—成员交换在伦理型领导行为与员工离职倾向之间起中介作用。 展开更多
关键词 伦理型领导 离职倾向 中国情境 领导—成员交换
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液压调速系统遗传算法优化前馈-反馈PID控制 被引量:22
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作者 魏晓朝 倪向东 +3 位作者 赵新 李申 韩双蔓 钟春发 《液压与气动》 北大核心 2020年第11期21-26,共6页
针对搭载液压机械无级变速器的非道路车辆在复杂工作环境下容易引起液压调速系统输出转速波动剧烈、稳定性下降等问题,提出一种基于液压调速系统的遗传算法优化前馈-反馈+PID转速复合控制方法。以系统输出转速平稳恒定为控制目标,将未... 针对搭载液压机械无级变速器的非道路车辆在复杂工作环境下容易引起液压调速系统输出转速波动剧烈、稳定性下降等问题,提出一种基于液压调速系统的遗传算法优化前馈-反馈+PID转速复合控制方法。以系统输出转速平稳恒定为控制目标,将未加控制时的马达转速分别与PID控制以及遗传算法优化前、后的前馈-反馈PID控制下的马达转速进行比较。仿真结果表明,遗传算法优化前馈-反馈PID控制使系统达到稳定状态时的超调量减少38.7%,调节时间减少3.5 s,提高了系统的抗负载干扰能力和转速控制性能。 展开更多
关键词 液压调速系统 遗传算法 前馈控制 转速控制
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基于有序Logit与Probit模型的交通事故严重性影响因素分析 被引量:21
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作者 胡骥 闫章存 +1 位作者 卢小钊 胡万欣 《安全与环境学报》 CAS CSCD 北大核心 2018年第3期836-843,共8页
为准确分析影响交通事故严重性的各项因素,引入有序选择模型中的Ordinal Logit模型和Ordinal Probit模型,研究驾驶员、车辆、环境、管理因素与事故严重程度之间的耦合关系,利用计量经济学理论和统计学方法对模型进行显著性检验。并选择... 为准确分析影响交通事故严重性的各项因素,引入有序选择模型中的Ordinal Logit模型和Ordinal Probit模型,研究驾驶员、车辆、环境、管理因素与事故严重程度之间的耦合关系,利用计量经济学理论和统计学方法对模型进行显著性检验。并选择美国北卡罗来纳州2010年至2014年385个翻车事故样本进行严重性影响因素分析,所得回归模型参数估计均符合Wald检验(p≤0.0001)和似然比检验(p≤0.0001),模型的拟合度也都符合Pearson检验(p=0.7976)、偏差检验(p=0.6006)和信息准则检验,模型预测精度指标值均大于0.7。所得两个模型中变量"安全带"(p≤0.001)、"路面状况"(p=0.0071)、"道路线形"(p=0.0077)、"路面类型"(p=0.0251)都对翻车事故的严重性具有显著影响,表明有序Logit模型和有序Probit模型均适用于分析和揭示影响交通事故严重性的各个因素。 展开更多
关键词 安全工程 交通事故严重程度 翻车事故 ORDINAL LOGIT模型 ORDINAL PROBIT模型
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冷榨花生粕蛋白多肽-亚铁螯合物制备工艺优化及结构分析 被引量:18
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作者 李玉珍 肖怀秋 +1 位作者 赵谋明 林亲录 《中国粮油学报》 EI CAS CSCD 北大核心 2017年第4期64-69,共6页
以酶法水解冷榨花生粕蛋白质粉制备得到的花生多肽液(<3 000 u)为原料,以氯化亚铁为金属螯合剂,在单因素试验基础上,利用Box-Behnken响应面优化技术对多肽-亚铁螯合条件进行优化分析并获得最优螯合工艺参数,即多肽-亚铁质量比为4.31:... 以酶法水解冷榨花生粕蛋白质粉制备得到的花生多肽液(<3 000 u)为原料,以氯化亚铁为金属螯合剂,在单因素试验基础上,利用Box-Behnken响应面优化技术对多肽-亚铁螯合条件进行优化分析并获得最优螯合工艺参数,即多肽-亚铁质量比为4.31:1(g/g),螯合温度为25.4 C,螯合时间28.5 min和螯合pH 7.5,在此优化条件下,多肽-亚铁螯合率为(85.68±1.27)%(n=3),与模型预测值89.653 1%接近,偏差为4.64%。花生粕蛋白多肽-亚铁螯合物经紫外光谱和红外光谱分析发现,Fe^(2+)与多肽中的NH_2^+以及COO-形成共价配位键并形成稳定的共轭结构,是一种新型有机金属螯合物。 展开更多
关键词 冷榨花生粕 多肽 多肽-亚铁螯合物 响应面优化
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2018年云南省外卖餐饮的微生物污染状况调查 被引量:15
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作者 国译丹 范璐 +3 位作者 汤小召 杨菁 何玉凤 田云屏 《食品安全质量检测学报》 CAS 2019年第22期7633-7638,共6页
目的了解云南省外卖食品的微生物污染情况。方法2018年从云南省8个地州市,以随机采样的方式,在饭店/酒店、快餐店、小吃店、便利店/零售店、网店共采集176件外卖餐饮样品,共计6类食品,按照GB 4789《食品安全国家标准食品微生物学检验》... 目的了解云南省外卖食品的微生物污染情况。方法2018年从云南省8个地州市,以随机采样的方式,在饭店/酒店、快餐店、小吃店、便利店/零售店、网店共采集176件外卖餐饮样品,共计6类食品,按照GB 4789《食品安全国家标准食品微生物学检验》的相关方法对7项微生物指标进行检测。结果176份样品中有98份卫生学指标检测结果不合格,不合格率55.68%,其中菌落总数不合格率为39.20%,大肠埃希氏菌计数不合格率16.48%;有11份食源性致病菌指标检测结果不合格,不合格率为6.25%,其中单增李斯特菌的检出率最高,为3.41%,沙门氏菌和金黄色葡萄球菌的检出率为1.14%,蜡样芽胞杆菌不合格率为0.57%,致泻大肠埃希氏菌未有检出;8个地州市中以普洱市、文山州、红河州、版纳州卫生学指标不合格率高,文山州与曲靖市的食源性致病菌指标不合格率高;6类外卖餐饮中,米面制品和中式凉拌菜不合格率最高;流通环节样品食源性致病菌指标不合格率高(7.80%),与服务环节样品(0.00%)存在显著性差异(尸<0.05);第三季度采集的样品不合格率最高,其次为第二季度;5种采样地点类型中,网店的食源性致病菌指标不合格率最高(7.91%),与其他4种类型的不合格率(0.00%)有显著性差异(戶<0.05)c.结论云南省外卖餐饮整体卫生状况不容乐观,有引发食物中毒的风险,应引起食品安全监管部门的高度重视,及时制定与完善外卖食品的相关安全标准,加强外卖食品的监督检査和监测,努力实现线上线下一体化多元监管。 展开更多
关键词 外卖餐饮 微生物污染 调査
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