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Chest CT features of children infected by B.1.617.2 (Delta) variant of COVID‑19

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World Journal of Pediatrics 2022年第1期18卷 37-42页

作者： Qi-Rui Cheng Ming-Xing Fan Jing Hao Xiao-Chen hu Xu-hua Ge zhi-Liang hu Zhuo Li Pediatric Intensive Care Unit Children’s Hospital of Nanjing Medical UniversityNo 72 Guanzhou RoadNanjingChina Nanjing Infectious Disease Center The Second Hospital of NanjingNanjing University of Chinese MedicineNanjingChina

Background This study aimed to explore the imaging characteristics,diversity and changing trend in CT scans of pediatric patients infected with Delta-variant strain by studying imaging features of children infected with Delta and comparing the results to those of children with original *** A retrospective,comparative analysis of initial chest CT manifestations between 63 pediatric patients infected with Delta variant in 2021 and 23 pediatric patients with COVID-19 in 2020 was *** imaging features were *** addition,the changing trend in imaging features of COVID-19 Delta-variant cases were explored by evaluating the initial and follow-up CT *** Among 63 children with Delta-variant COVID-19 in 2021,34(53.9%)showed positive chest CT presentation;and their CT score(1.10±1.41)was signifcantly lower than that in 2020(2.56±3.5)(P=0.0073).Lesion distribution:lung lesions of Delta cases appear mainly in the lower lungs on both *** children had single lobe involvement(18 cases,52.9%),14(41.2%)in the right lung alone,and 14(41.2%)in both lungs.A majority of Delta cases displayed initially ground glass(23 cases,67.6%)and nodular shadows(13 cases,38.2%)in the frst CT scan,with few extrapulmonary *** 34 children with abnormal chest CT for the frst time have a total of 92 chest CT *** children showed a statistically signifcant diference between the 0-3 day group and the 4-7 day group(P=0.0392)and a signifcant diference between the 4-7 day group and the more than 8 days group(P=0.0003).Conclusions The early manifestations of COVID-19 in children with abnormal imaging are mostly small subpleural nodular ground glass *** changes on the Delta-variant COVID-19 chest CT were milder than the original *** lesions reached a peak on CT in 4-7 days and quickly improved and absorbed after a *** CT re-examination can achieve a good prognosis.

关键词： B.1.617.2(Delta)variant Children Coronavirus disease 2019(COVID-19) Chest computed tomography(CT)

Relationship between red blood cell distribution width levels and atrial fibrillation in hypertensive patients

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Journal of Geriatric Cardiology 2020年第8期17卷 486-494页

作者： Li-hui ZHENG Shang-Yu LIU Feng hu zhi-Cheng hu Li-Shui SHEN Ling-Min WU Yan YAO Arrhythmia Center Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background Information on the relationship between red blood cell distribution width(RDW)and atrial fibrillation(AF)in patients with essential hypertension are *** study aimed to assess the relationship between AF and RDW in hypertensive *** We enrolled 432 hypertensive patients,including 350 AF patients and 82 patients as ***'demographic,clinical,laboratory and echocardiographic characteristics were *** AF patients were further divided into the persistent and paroxysmal AF *** were monitored to identify the cardiac rhythm during blood sampling,and based on the rhythm,the paroxysmal AF group was categorized into the presence(with AF rhythm during blood sampling)and absence(with sinus rhythm during blood sampling)*** The AF group had elevated RDW levels than the controls(12.7%±0.8%vs.12.4%±0.7%,P=0.002),and the persistent AF subgroup had higher RDW levels than the paroxysmal AF subgroup(12.9%±0.8%vs.12.6%±0.8%,P=0.007).Furthermore,in the paroxysmal AF group,the presence group had higher RDW levels than the absence group(13.0%±0.6%vs.12.5%±0.9%,P=0.001).There was no significant difference in RDW levels between the persistent AF subgroup and presence group of the paroxysmal AF subgroup(P=0.533)and between the absence group of the paroxysmal AF subgroup and control group(P=0.262).In multivariate regression analysis,in hypertensive patients,the presence of AF rhythm is an independent predictor for increased RDW concentration(P=0.001).Conclusions The RDW may be associated with the presence of AF rhythm,which implies the importance of maintaining the sinus rhythm in hypertensive patients.

关键词： Atrial fibrillation Hypertension Inflammation Red blood cell distribution width

Influence of formation heterogeneity on foam flooding performance using 2D and 3D models:an experimental study

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Petroleum Science 2020年第3期17卷 734-748页

作者： Ling-zhi hu Lin Sun Jin-Zhou Zhao Peng Wei Wan-Fen Pu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500SichuanChina MOE Key Laboratory of Oil and Gas Fine Chemicals School of Chemistry and Chemical Engineering.Xinjiang UniversityUrumchi 830046XinjiangChina Yumen Oilfield of Chinese National Petroleum Corp.Yumen 735211 GansuChina

The formation heterogeneity is considered as one of the major factors limiting the application of foam *** this paper,influences of formation properties,such as permeability,permeability distribution,interlayer,sedimentary rhythm and 3D heterogeneity,on the mobility control capability and oil displacement efficiency of foam flooding,were systematically investigated using 2D homogeneous and 2D/3D heterogeneous models under 120°C and salinity of 20×10~4 mg/*** flow resistance of foam was promoted as the permeability increased,which thus resulted in a considerable oil recovery *** the scenario of the vertical heterogeneous formations,it was observed that the permeability of the high-permeable layer was crucial to foam mobility control,and the positive rhythm appeared favorable to improve the foam flooding *** additional oil recovery increased to about 40%.The interlayer was favorable for the increases in mobility reduction factor and oil recovery of foam flooding when the low permeability ratio was *** the 3D heterogeneous formations,foam could efficiently adjust the areal and vertical heterogeneity through mobility control and gravity segregation,and thus enhancing the oil recovery to 11%–14%.The results derived from this work may provide some insight for the field test designs of foam flooding.

关键词： Foam flooding Permeability ratio 2D/3D models Heterogeneity Enhanced oil recovery

Effect of 6H-SiC crystal growth shapes on thermo-elastic stress in the growing crystal

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 622-627页

作者： Yong-gui Shi Pei-yun Dai Jian-feng Yang zhi-hao Jin hu-lin Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 China

The effect of 6H-SiC crystal growth shapes on the thermo-elastic stress distribution in the growing crystal was systematically in- vestigated by using a finite element method. The thermo-elastic stress distribution in the crystal with a flat growth shape was more homoge- neous than that in the crystals with concave and convex growth shapes, and the value of thermo-elasticity in the crystal with a fiat growth shape was also smaller than that in the two other types of crystals. The maximum values of thermo-elastic stress appeared at interfaces be- tween the crystal and the graphite lid. If the lid was of the same properties as 6H-SiC, the thermo-elastic stress would decrease in two orders of magnitude. Thus, to grow 6H-SiC single crystals of high quality, a transition layer of SiC formed by deposition or reaction is suggested; meanwhile the thermal field in the growth chamber should be adjusted to maintain the crystals with fiat growth shapes.

关键词： silicon carbide thermo-elasticity physical vapor transport single crystals crystal growth finite element method

Lactic Acid Inhibits NF-kB Activation by Lipopolysaccharide in Rat Intestinal Mucosa Microvascular Endothelial Cells

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Agricultural Sciences in China 2011年第6期10卷 954-959页

作者： LIU Jing XUE Jiu-zhou Zhu zhi-ning hu Ge REN Xiao-ming Animal Science and Technology College Beijing University of Agriculture Beijing 102206 P.R. China

To investigate whether lactic acid could inhibit the LPS-activation of NF-κB p65 in rat intestinal mucosa microvascular endothelial cells （RIMMVECs）, RIMMVECs, cultured in vitro, were pretreated with different concentrations of lactic acid and then exposed to lipopolysaccharide （LPS）. Cells and cell culture media were then collected at different time intervals. Production of tumor necrosis factor-a （TNF-a） and interleukin-6 （IL-6） was examined at the protein level by enzyme-linked immunosorbent assay. The influence of lactic acid on the LPS-activation of NF-κB was examined at mRNA and protein levels by real-time quantitative PCR and Western blot analysis, respectively. TNF-a and IL-6 protein levels were significantly decreased after pretreatment with lactic acid compared with cells exposed to LPS only. After pretreatment with 7.5, 5.0, and 2.5 μL mL-1 lactic acid, NF-κB mRNA levels were increased by 1.51-, 2.62- and 3.00-fold, respectively, compared with levels in control cells without LPS treatment. Western blot analysis indicated that the level of NF-κB p65 in the lactic acid-pretreated group was significantly lower than that in the group treated with LPS only （positive control） and was unchanged compared with the group without LPS treatment （blank control）. These results suggest that lactic acid may inhibit LPS-activation of NF-κB, leading to the down-regulation of TNF-a and IL-6.

关键词： lactic acid RMMIVECs LPS NF-κB

User preferences-aware recommendation for trustworthy cloud services based on fuzzy clustering

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Journal of Central South University 2015年第9期22卷 3495-3505页

作者：马华胡志刚 School of Software Central South University School of Information Science and Engineering Hunan International Economics University

The cloud computing has been growing over the past few years, and service providers are creating an intense competitive world of business. This proliferation makes it hard for new users to select a proper service among a large amount of service candidates. A novel user preferences-aware recommendation approach for trustworthy services is presented. For describing the requirements of new users in different application scenarios, user preferences are identified by usage preference, trust preference and cost preference. According to the similarity analysis of usage preference between consumers and new users, the candidates are selected, and these data about service trust provided by them are calculated as the fuzzy comprehensive evaluations. In accordance with the trust and cost preferences of new users, the dynamic fuzzy clusters are generated based on the fuzzy similarity computation. Then, the most suitable services can be selected to recommend to new users. The experiments show that this approach is effective and feasible, and can improve the quality of services recommendation meeting the requirements of new users in different scenario.

关键词： trustworthy service service recommendation user preferences-aware fuzzy clustering

Clinical operational tolerance in liver transplantation:state-of-the-art perspective and future prospects

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Hepatobiliary & Pancreatic Diseases International 2013年第1期12卷 12-33页

作者： Xi-Qiang Liu zhi-Qiu hu Yao-Fei Pei Ran Tao Center for Organ Transplantation and Department of Surgery Ruijin HospitalShanghai Jiaotong University School of Medicine Department of Surgery Central Hospital of Minghang District

BACKGROUND:Liver transplantation is the definite treatment for end-stage liver diseases with satisfactory ***,untoward effects of life-long immunosuppression prevent the development of alternative strategies to achieve better longterm *** clinical operational tolerance is the ultimate *** SOURCES:A PubMed and Google Scholar search using terms:"immune tolerance","liver transplantation","clinical trial","operational tolerance" and "immunosuppression withdrawal" was performed,and relevant articles published in English in the past decade were ***-text publications relevant to the field were selected and relevant articles from reference lists were also *** was given to those articles which are relevant to the ***:Because of the inherent tolerogenic property,around 20%-30% of liver transplantation recipients develop spontaneous operational tolerance after immunosuppression withdrawal,and the percentage may be even higher in pediatric living donor liver transplantation *** natural killer and γδT cell related markers have been identified to be associated with the tolerant state in liver transplantation *** the progress,clinical operational tolerance is still rare in liver *** the recipient immune system by creating chimerism and regulatory cell therapies is among newer promising means to achieve clinical liver transplantation tolerance in the ***:Although clinical operational tolerance is still rare in liver transplantation recipients,ongoing basic research and collaborative clinical trials may help to decipher the mystery of transplantation tolerance and extend the potential benefits of drug withdrawal to an increasing number of patients in a more predictable fashion.

关键词： immune tolerance liver transplantation clinical trial

Quasi-in-situ Observation and SKPFM Studies on Phosphate Protective Film and Surface Micro-Galvanic Corrosion in Biological Mg-3Zn-xNd Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 648-664页

作者： Zhaochen Yu Kaixuan Feng Shuyun Deng Yang Chen Hong Yan Honggun Song Chao Luo zhi hu School of Advanced Manufacturing Nanchang UniversityNanchang330031China Institute for Advanced Study Nanchang UniversityNanchang330031China

The phosphate protective film and micro-galvanic corrosion of biological Mg-3Zn-xNd (x = 0, 0.6, 1.2) alloys were investigated by scanning and transmission electron microscopy, quasi-in-situ observation, scanning Kelvin probe force microscopy (SKPFM) and electrochemical tests. The results revealed the Mg-Zn-Nd phases formed in Mg-3Zn alloy contained with Nd. Adding Nd resulted in a significant decline in the cracks of the phosphate protective film and micro-galvanic corrosion of alloys, which were recorded by quasi-in-situ observation. In addition, the Volta potential difference of Mg-Zn-Nd/α-Mg (~ 188 mV) was lower than MgZn/α-Mg (~ 419 mV) and Zn-rich/α-Mg (~ 260 mV), and the corrosion rates of alloys markedly decreased after the addition of 0.6 wt% Nd. The improvement in corrosion resistance of Nd-containing alloys was mainly attributed to the following: (i) the addition of Nd reduced the Volta potential difference (second phases/α-Mg);(ii) the phosphate protective film containing Nd_(2)O_(3) deposited on the surface of the alloys, effectively preventing the penetration of harmful anions.

关键词： Magnesium alloys Quasi-in-situ observation Phosphate protective film Scanning Kelvin probe force microscopy(SKPFM) Micro-galvanic corrosion

Perylene Diimide Based Isomeric Conjugated Polymers as Efficient Electron Acceptors for All-polymer Solar Cells

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Chinese Journal of Polymer Science 2019年第1期37卷 18-27,1-5页

作者： Xiao-Cheng Liu Qing-Wu Yin zhi-Cheng hu Zhen-Feng Wang Fei huang Yong Cao State Key Laboratory of Luminescent Materials and Devices School of Materials Science and Engineering South China University of Technology South China Institute of Collaborative Innovation

We present here a series of perylene diimide(PDI)based isomeric conjugated polymers for the application as efficient electron acceptors in all-polymer solar cells(all-PSCs).By copolymerizing PDI monomers with 1,4-diethynylbenzene(para-linkage)and 1,3-diethynylbenzene(meta-linkage),isomeric PDI based conjugated polymers with parallel and non-parallel PDI units inside backbones were *** was found that para-linked conjugated polymer(PA)showed better solubility,strongerπ-πstacking,more favorable blend morphology,and better photovoltaic performance than those of meta-linked conjugated polymers(PM)*** based on PTB7-Th:PA(PTB7-Th:poly{4,8-bis[5-(2-ethylhexyl)-thiophen-2-yl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophene-4,6-diyl})showed significantly enhanced photovoltaic performance than that of PTB7-Th:MA(3.29%versus 0.92%).Moreover,the photovoltaic performance of these polymeric acceptors could be further improved via a terpolymeric *** copolymerizing a small amount of meta-linkages into PA,the optimized terpolymeric acceptors enabled to enhance photovoltaic performance with improved the short-circuit current density(Jsc)and fill factor(FF),resulting in an improved power conversion efficiency(PCE)of 4.03%.

关键词： Isomeric conjugated polymers All-polymer solar cells Electron acceptors Perylene diimide