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1The China Multi-Model Ensemble Prediction System and Its Application to Flood-Season Prediction in 2018显示文摘Multi-model ensemble prediction is an effective approach for improving the prediction skill short-term climate prediction and evaluating related uncertainties. Based on a combination of localized operation outputs of Chinese climate models and imported forecast data of some international operational models, the National Climate Center of the China Meteorological Administration has established the China multi-model ensemble prediction system version 1.0 (CMMEv1.0) for monthly-seasonal prediction of primary climate variability modes and climate elements. We verified the real-time forecasts of CMMEv1.0 for the 2018 flood season (June-August) starting from March 2018 and evaluated the 1991-2016 hindcasts of CMMEv1.0. The results show that CMMEv1.0 has a significantly high prediction skill for global sea surface temperature (SST) anomalies, especially for the El Nino-Southern Oscillation (ENSO) in the tropical central-eastern Pacific. Additionally, its prediction skill for the North Atlantic SST triple (NAST) mode is high, but is relatively low for the Indian Ocean Dipole (IOD) mode. Moreover, CMMEv1.0 has high skills in predicting the western Pacific subtropical high (WPSH) and East Asian summer monsoon (EASM) in the June-July-August (JJA) season. The JJA air temperature in the CMMEv1.0 is predicted with a fairly high skill in most regions of China, while the JJA precipitation exhibits some skills only in northwestern and eastern China. For real-time forecasts in March-August 2018, CMMEv1.0 has accurately predicted the ENSO phase transition from cold to neutral in the tropical central-eastern Pacific and captures evolutions of the NAST and IOD indices in general. The system has also captured the main features of the summer WPSH and EASM indices in 2018, except that the predicted EASM is slightly weaker than the observed. Furthermore, CMMEv1.0 has also successfully predicted warmer air temperatures in northern China and captured the primary rainbelt over northern China, except that it predicted much more precipitation in the middle and lower reaches of the Yangtze River than observation.Hong-Li REN Yujie WU Qing BAO Jiehua MA Changzheng LIU Jianghua WAN Qiaoping LI Xiaofei WU Ying LIU Ben TIAN Joshua-Xiouhua FU Jianqi SUN 2019Journal of Meteorological Research2019,33,3:16
2Postreperfusion syndrome during orthotopic liver transplantation:a single-center experience显示文摘BACKGROUND: Marked hemodynamic alteration, commonly referred to as postreperfusion syndrome (PRS), often occurs after revascularization of the donor organ during orthotopic liver transplantation (OLT) and is associated with poor outcomes. This study aimed to investigate the incidence, predictive factors and clinical outcomes of PRS in Chinese patients following OLT at a liver transplantation center in China. METHODS: Over a 5-year period, 330 consecutive patients who had undergone OLT for hepatocellular carcinoma or cirrhosis were included in this retrospective study. PRS was defined as a >30% decrease in the mean arterial pressure compared with that before revascularization for more than 1 minute during the first 5 minutes of graft reperfusion. The patients were divided into 2 groups according to the development of PRS: group 1 (patients with PRS, n=56) and group 2 (patients without PRS, n=274). The demographic characteristics, operative and postoperative courses, and outcomes of the patients were analyzed using SPSS version 18.0. RESULTS: Multivariate regression analysis showed that left ventricular diastolic dysfunction determined by echocardiography and prolonged cold ischemia time were the independent risk factors for PRS. More patients in group 1 showed postoperative renal dysfunction than those in group 2 (19.23% vs 8.4%). Moreover, patients in group 1 also had higher intraoperative (7.14% vs 0%) and postoperative mortalities (26.92% vs 12.04%).CONCLUSION: Left ventricular diastolic dysfunction and prolonged cold ischemia time contribute to a high incidence of PRS, which is associated with adverse outcomes in Chinese patients following OLT.Zhen-Dong Xu, Hai-Tao Xu, Hong-Bin Yuan, Hao Zhang, Rui-Hua Ji, Zui Zou, Zhi-Ren Fu and Xue-Yin Shi Department of Anesthesiology, Huashan Hospital, Fudan University, Shanghai 200040, China Department of Anesthesiology Organ Transplantation Center , Changzheng Hospital, Second Military Medical University, Shanghai 200003, China 2012Hepatobiliary & Pancreatic Diseases International2012,11,1:15
3Inhibition of hepatitis B virus by oxymatrine in vivo显示文摘AIM To investigate the anti-HBV effect ofoxymatrine (oxy) in vivo.METHODS HBV transgenic mice were producedby micro-injection of a 4.2kb fragmentcontaining the complete HBV genomes.Expression level of HBsAg and HBcAg in thetransgenic mice liver was determined byimmunohistochemical assay.RESULTS Four groups (6 mice in each group)were injected intraperitoneally with oxy at thedosage of 100,200, and 300 mg/kg or with salineonce a day for 30 days. Both HBsAg and HBcAgwere positive in livers of all the six mice in thecontrol group (injected with saline), and werepositive in livers of two mice in 100 mg/kg groupand 300mg/kg group. In 200mg/kg group,HBsAg and HBcAg were negative in livers of allthe six mice. Based on the results, 200 mg/kg isthe ideal dosage to explore the effect of oxy atdifferent time points. According to the oxytreatment time, mice were divided into fourgroups: 10 d, 20 d, 30 d and 60 d (4 mice in eachgroup). Each mouse underwent liver biopsy twoweeks before the treatment of oxy. Down-regulation of HBsAg and HBcAg appeared aftertreatment of oxymatrine for 10 d and 20 d, Dane-like particles disappeared after the treatment ofoxy for 20d under electron microscopy,however, the expression level of HBsAg andHBcAg returned to normal 60 d later after oxytreatment.CONCLUSION oxymatrine can reduce thecontents of HBsAg and HBcAg in transgenic miceliver, longer treatment time and larger dosagedo not yield better effects.Xiao Song Chen1 Guo Jun Wang1 Xiong Cai1 Hong Yu Yu2 Yi Ping Hu3 1Department of Infectious Diseases, Changzheng Hospital, the Second Military Medical University, Shanghai 200003, China2Department of Pathology, 3Department of Cell Biology, Department of Basic Medicine, the Second Military Medical University, Shanghai 200433, China 2001World Journal of Gastroenterology2001,7,1:13
4Maximal Dimension of Invariant Subspaces to Systems of Nonlinear Evolution Equations显示文摘In this paper,the dimension of invariant subspaces admitted by nonlinear systems is estimated under certain conditions.It is shown that if the two-component nonlinear vector differential operator F=(F 1,F 2) with orders {k 1,k 2 } (k 1 ≥ k 2) preserves the invariant subspace W 1 n 1 × W 2 n 2 (n 1 ≥ n 2),then n 1 n 2 ≤ k 2,n 1 ≤ 2(k 1 + k 2) + 1,where W q n q is the space generated by solutions of a linear ordinary differential equation of order n q (q=1,2).Several examples including the (1+1)-dimensional diffusion system and Ito 's type,Drinfel'd-Sokolov-Wilson's type and Whitham-Broer-Kaup's type equations are presented to illustrate the result.Furthermore,the estimate of dimension for m-component nonlinear systems is also given.Shoufeng SHEN Changzheng QU Yongyang JIN Lina JI 2012Chinese Annals of Mathematics,Series B2012,33,2:13
5Cardiac arrest after graft reperfusion during liver transplantation显示文摘BACKGROUND: Cardiac arrest ( CA) during orthotopic liver transplantation (OLT) is rare but it threatens the lives of patients. The cause of perioperitive CA is not fully understood. We reported the occurrence of CA in 5 patients after unclamping of the vena cava and investigated the relationship between CA and associated variables. METHODS: Five patients with CA after graft reperfusion during OLT in our unit from November 1996 to September 2003 were retrospectively reviewed. Analyzed data included donor and recipient demographic data, and recipient operative and postoperative events. RESULTS: Five (2.1%) of 240 patients undergoing OLT experienced CA 5 minutes after graft reperfusion. Two patients died of resuscitation failure. Hyperkalemia and metabolic acidosis after revascularization were observed in some patients. The five patients had hypothermia and hypocalce-mia, and one had pulmonary embolism. CONCLUSIONS: CA is one of the syndromes after reperfusion. Many factors such as hyperkalemia, acidosis or pulmonary embolism combined with hypothermia and hy-pocalcemia during the operation seem to contribute to the occurrence of CA.Xue-Yin Shi, Zhen-Dong Xu, Hai-Tao Xu, Jin-Jin Jiang and Gang Liu Department of Anesthesiology, Changzheng Hospital, Second Military Medical University,Shanghai 200003 , China 2006Hepatobiliary & Pancreatic Diseases International2006,5,2:10
6Invariant subspaces and conditional Lie-Bcklund symmetries of inhomogeneous nonlinear difusion equations显示文摘The inhomogeneous nonlinear difusion equation is studied by invariant subspace and conditional Lie-Bcklund symmetry methods.It is shown that the equations admit a class of invariant subspaces governed by the nonlinear ordinary diferential equations,which is equivalent to a kind of higher-order conditional Lie-Bcklund symmetries of the equations.As a consequence,a number of new solutions to the inhomogeneous nonlinear difusion equations are constructed explicitly or reduced to solving fnite-dimensional dynamical systems.QU ChangZheng JI LiNa 2013Science China Mathematics2013,56,11:10
7IL-10-Producing Type 1 Regulatory T Cells and Allergy显示文摘As an important subset of regulatory T(Treg) cells,IL-10-producing type 1 regulatory T cells(Tr1) ,have some different features to thymic-derived naturally occurring CD4+CD25+Foxp3+ Treg cells(nTreg cells) . Similar to nTreg cells,Tr1 also play important roles in the control of allergic inflammation in several ways. There is a fine balance between Tr1 and Th2 responses in healthy subjects. Skewing of allergic-specific effctor T cells to a Tr1 phenotype appears to be a critical event in successful allergen-specific immunotherapy and glucocorticoids and β2-agonists treatment. Tr1 suppress Th2 cells and effector cells of allergic inflammation,such as eosinophils,mast cells,basophils,through producing IL-10,and perhaps TGF-β. Understanding of Tr1 may be helpful in developing new strategies for treatment of allergic diseases.Kui Wu Yutian Bi Kun Sun Changzheng Wang 2007Cellular & Molecular Immunology2007,4,4:9
8Analysis of HLA alleles polymorphism in Chinese patients with primary biliary cirrhosis显示文摘BACKGROUND: A familial dustering of patients with primary biliary cirrhosis (PBC) and the presence of immunological abnormalities in family members suggest a genetic component involved in the pathogenesis of PBC. The aims of this study are to investigate the frequencies of human leukocyte antigen HLA-A, -B, and -DRB1 alleles in Chinese patients with PBC by polymerase chain reaction (PCR)-based techniques, and to assess the correlation of the above-mentioned HLA with some clinical and laboratory features. METHODS: Genotyping of HLA alleles were performed in 65 well-characterized PBC patients and 431 healthy controls with sequence-specifc primers PCR amplification. RESULTS: HLA-DRB1~*07 allele detected in 19 of the 65 (29.2%) PBC patients was subtyped as DRB1~*0701, as well as in 13.9% of controls (P_C<0.05, OR=2.55, 95% CI: 1.4-4.6). An increased frequency of DRB1~*03 (18.4% vs. 7.2% in healthy controls) and a decreased frequency of DRB1~*12 (16.9% vs. 28.8%) in PBC patients were statistically significant. There was no association with HLADRB1~*08 reported. The frequencies for HLA-A, B and the other DRB1 alleles were similar between patients and healthy controls. CONCLUSIONS: The susceptibility to PBC in Chinese individuals is associated with DRB1~*0701 allele. This association differs from that in North Americans, South Americans, North Europeans and even Japanese, but it is not restricted to any particular subgroup of patients.Hai-Ying Liu. An-Mei Deng, Ye Zhou, Ding-Kang Yao, De-Xing Xu and Ren-Qian Zhong Clinical Laboratory, General Hospital of Guangzhou Military Command of PLA, Guangzhou 510010, China Laboratory Diagnostics, Changzheng Hospital, Second Military Medical University, and Clinical Immunology Center of PLA, Shanghai 200003, China and Department of Gastroenterology, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China 2006Hepatobiliary & Pancreatic Diseases International2006,5,1:9
9Symmetry and nonexistence of positive solutions to an integral system with weighted functions显示文摘Consider the system of integral equations with weighted functions in Rn,{u(x) =∫Rn|x-y|α-nQ(y)v(y)qdy1,v(x)=∫Rn|x-y|α-nK(y)u(y)pdy,where 0 < α < n,1/(p+1) + 1/(q+1)≥(n-α)/n1,α/(n-α) < p1q < ∞1,Q(x) and K(x) satisfy some suitable conditions.It is shown that every positive regular solution(u(x)1,v(x)) is symmetric about some plane by developing the moving plane method in an integral form.Moreover,regularity of the solution is studied.Finally,the nonexistence of positive solutions to the system in the case 0 < p1q <(n+α)/(n-α) is also discussed.DOU JingBo QU ChangZheng HAN YaZhou 2011Science China Mathematics2011,54,4:8
10Correction of Observation Interference on Z component of Geomagnetic Field From DC Power Lines显示文摘为减小直流输电线路对地磁场观测的干扰,采用数学计算的方法精确求解了线路对地磁Z分量的干扰水平。以观测点为原点建立了地磁仪器观测点坐标系,推导了观测点坐标系各坐标轴在地心坐标系中的单位矢量表达式。根据空间矢量点积的定义,得到了空间电流磁场矢量投影到地磁Z分量方向的求解公式。利用推导的公式和直流线路电流磁场三维计算模型,最终求得直流线路对地磁Z分量观测的干扰水平。由此,开发了"直流线路对地磁观测干扰校正系统",并开展了地磁台站和野外联合地磁观测干扰实验。结果表明,直流线路和地磁观测台站距离不超过10km时,提出的数学模型和计算方法误差不超过5%。TANG Bo ZHANG Jiangong MENG Suimin LIU Xingfa DENG Changzheng 2012中国电机工程学报2012,32,30:8
11The Chinese Hα Solar Explorer(CHASE) mission: An overview显示文摘The Chinese Hα Solar Explorer(CHASE), dubbed “Xihe”—Goddess of the Sun, was launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission is designed to test a newly developed satellite platform and to acquire the spectroscopic observations in the Hα waveband. The Hα Imaging Spectrograph(HIS)is the scientific payload of the CHASE satellite. It consists of two observational modes: raster scanning mode and continuum imaging mode. The raster scanning mode obtains full-Sun or region-of-interest spectral images from 6559.7 to 6565.9 ? and from 6567.8 to 6570.6 ? with 0.024 ? pixel spectral resolution and 1 min temporal resolution. The continuum imaging mode obtains photospheric images in continuum around 6689 ? with the full width at half maximum of 13.4 ?. The CHASE mission will advance our understanding of the dynamics of solar activity in the photosphere and chromosphere. In this paper, we present an overview of the CHASE mission including the scientific objectives, HIS instrument overview, data calibration flow, and first results of on-orbit observations.Chuan Li Cheng Fang Zhen Li MingDe Ding PengFei Chen Ye Qiu Wei You Yuan Yuan MinJie An HongJiang Tao XianSheng Li Zhe Chen Qiang Liu Gui Mei Liang Yang Wei Zhang WeiQiang Cheng JianXin Chen ChangYa Chen Qiang Gu QingLong Huang MingXing Liu ChengShan Han HongWei Xin ChangZheng Chen YiWei Ni WenBo Wang ShiHao Rao HaiTang Li Xi Lu Wei Wang Jun Lin YiXian Jiang LingJie Meng Jian Zhao 2022Science China(Physics,Mechanics & Astronomy)2022,65,8:7
12Metallic mesocrystal nanosheets of vanadium nitride for high-performance all-solid-state pseudocapacitors显示文摘转变金属氮化物(TMN ) 具有由他们优异电的电导率,优秀环境耐久性和高反应选择的协作优点的优点的特别兴趣,还完成灵活设计和操作是困难的。此处,钒氮化物(VN ) 的 mesocrystal nanosheets (MCNS ) 从热地稳定的分层的钒铜经由一条范围生长线路被综合,代表第一二维(2D ) 在无机的混合物的金属性的 mesocrystal。从他们的 single-crystalline-like 有益于远程的电子连接, VN MCNS 交付 1.44 的电的传导性 ??? 汰獵瀭畬 ??  ̄吗?Wentuan Bi Zhenpeng Hu Xiaogang Li Changzheng Wu Junchi Wu Yi Xie 2015Nano Research2015,8,1:7
13Nonselective etching of GaN/AlGaN heterostructures by Cl2/Ar/BCl3 inductively coupled plasmas显示文摘A systematic study of the nonselective and smooth etching of GaN/AIGaN het-erostructures was performed using C12/Ar/BCI3 inductively coupled plasmas (ICR).Nonselective etching can be realized by adjusting the BCI3 ratio in the Cl2/Ar/BCI3 mixture (20%—60%), increasing the ICR power and dc bias, and decreasing the chamber pressure. Surface morphology of the etched heterostructures strongly depends on the gas chemistry and the chamber pressure. Specifically, with the addition of 20% BCI3 to Cl2/Ar (4:1) gas mixture, nonselective etching of GaN/Al0.28Ga0.72N heterostructures at high etch rate is maintained and the surface root-mean-square (rms) roughness is reduced from 10.622 to 0.495 nm, which is smoother than the as-grown sample. Auger electron spectroscopy (AES) analysis shows that the effective removal of residual oxygen from the surface of AIGaN during the etching process is crucial to the nonselective and smooth etching of GaN/AIGaN herterostructures at high etch rate.HAN Yanjun XUE Song WU Tong WU Zhen GUO Wenping LUO Yi HAO Zhibiao SUN Changzheng 2004Science China(Technological Sciences)2004,47,2:6
14Prevention of hepatitis B virus reinfection after orthotopic liver transplantation显示文摘BACKGROUND: Hepatitis B virus reinfection is an impor-tant problem after liver transplantation. The aim of thisstudy was to discuss the prevention of hepatitis B virus rein-fection following orthotopic liver transplantation.METHODS: Sixty-eight cases of chronic fulminant hepatitisB, end-stage liver cirrhosis, and liver carcinoma complicat-ed with HBV cirrhosis were given anti-viral drugs beforeand after transplantation to prevent hepatitis B virus rein-fection. Lamivudine was administered in 2 patients, lami-vudine + hepatitis B immunoglobulin ( HBIG ) in 63, andadefovir + HBIG in 3. The measurement of serum HBV,HBV DNA, liver biopsy immunohistochemistry and clini-cal study were performed.RESULTS: In 1 of the 2 patients who developed reinfectionafter lamivudine administration, serum HBsAg, HBeAb,HBcAb, HBV DNA were positive and liver biopsy immu-nohistochemistry showed HBsAg phenotype. In 2 of 63 pa-tients who developed reinfection after use of lamivudine +HBIG, serum HBsAg, HBeAb, HBcAb were positive andliver biopsy immunohistochemistry showed HBsAg pheno-type. Serum HBV DNA was positive in one of them.Three patients developed no reinfection with HBV after useof adefovir.CONCLUSIONS: Orthotopic liver transplantation is effectivein the treatment of HBV-infected diseases. Lamivudine +HBIG or adefovir + HBIG could effectively prevent hepatitisB virus reinfection.Zheng-Xin Wang, Guo-Shan Ding, Hong Fu, Jian-Jun Zhang, Xiao-Song Chen,Wen-Yuan Guo, Xiao-Min Shi and Zhi-Ren Fu Liver Transplantation Group of Transplantation Cen-ter , Changzheng Hospital, Second Military University, Shanghai 200003,China 2004Hepatobiliary & Pancreatic Diseases International2004,3,3:6
15Realizing high low-electric-field energy storage performance in AgNbO_(3) ceramics by introducing relaxor behaviour显示文摘Both sustainable development in environment and safety of high-power systems require to develop a novel lead-free dielectric capacitor with high energy density(Wrec)at low applied electric field.In this work,a remarkably high Wrec of 2.9 J/cm^(3) accompanying with energy storage efficiency of 56% was achieved in Ag_(0.9)Sr_(0.05)NbO_(3) ceramic at a low applied electric field of 190 kV/cm,by improving antiferroelectricity and introducing relaxor behaviour.The improved anti-ferroelectric stability was attributed to the decreased tolerance factor and average electronegativity difference,while the relaxor behaviour was associated with the increased disordered local structure by Sr-doping.Moreover,the Ag_(0.9)Sr_(0.05)NbO_(3) ceramics also exhibited outstanding temperature stability in energy density with small variation less than 5% over 20-140℃.The results indicate that the Ag_(0.9)Sr_(0.05)NbO_(3) ceramic is a promising candidate for low-electric-field driving capacitors.Kai Han Nengneng Luo Shuaifei Mao Fangping Zhuo Xiyong Chen Laijun Liu Changzheng Hu Huanfu Zhou Xinpeng Wang Yuezhou Wei 2019Journal of Materiomics2019,5,4:5
16Crystal Structures, Thermal Analysis and Electrochemical Behaviors of Functionalized Pyridinium Ionic Liquids Comprising One 1-Ethyl Acetate Group显示文摘ZHAO Yamei CUI Hongmeng ZHENG Changzheng CHEN Xiaogang LI Chunyang 2016Chemical Research in Chinese Universities2016,32,1:5
17Activities of the Deriviatives of Chitin on the Osbeoblast Proliferation and the Effect on Bone Strength in Ovariectomized Rats显示文摘This study intends to examine the effects of different concentrations of four kinds of degradations of chitin: glucosamine (GLC),N-acetyl-D-glucosamine (NAG), chitooligosaccharide(COS),CM-chitooligosaccharide (CM-COS) —on the proliferation of MC3T3-E1 cell line cultured in vitro. Results suggest that all of the glucoses mentioned above promoted the proliferation of osteoblast, and various concentrations have different effects: the proliferation was remarkable when the concentration of GLC, NAG, COS, CM-COS was 100 , 100 , 500 , 500 μg/mL ,respectively. Furthermore we choose the glucosamine as the material and study the effect on the bone strength in ovariectomized rats. The results showed that the middle does of glucosamine can significantly increase the bone strength of femur in ovariectomized rats.WEI Changzheng LIU Wanshun HAN Baoqin DUAN Yixiang 2006Wuhan University Journal of Natural Sciences2006,11,3:5
18Aqueous Synthesis of Mesostructured BiVO_(4) Quantum Tubes with Excellent Dual Response to Visible Light and Temperature显示文摘Analysis of the atomic structure of monoclinic BiVO4 reveals its fascinating structure-related dual response to visible light and temperature.Although there have been a few reported studies of its responses to visible light and temperature,an understanding of the effects of quantum size,particle shape or specific exposed facets on its dual responsive properties remains elusive;this is primarily due to the limited availability of high-quality monodisperse nanocrystals with extremely small sizes and specific_(4)exposed facets.Herein,we describe a novel assembly-fusion strategy for the synthesis of mesostructured monoclinic BiVO_(4)quantum tubes with ultranarrow diameter of 5 nm,ultrathin wall thickness down to 1 nm and exposed{020}facets,via a convenient hydrothermal method at temperatures as low as 100℃.Notably,the resulting high-quality quantum tubes possess significantly superior dual-responsive properties compared with bulk BiVO_(4)or even BiVO4 nanoellipsoids,and thus,show high promise for applications as visible-light photocatalysts and temperature indicators offering improved environmental quality and safety.This mild and facile methodology should be capable of extension to the preparation of other mesostructured inorganic quantum tubes with similar characteristics,giving a range of materials with enhanced dual-responsive properties.Yongfu Sun Yi Xie Changzheng Wu Shudong Zhang Shishi Jiang 2010Nano Research2010,3,9:4
19Responsive changes of rumen microbiome and metabolome in dairy cows with different susceptibility to subacute ruminal acidosis显示文摘Subacute ruminal acidosis(SARA)represents one of the most important digestive disorders in intensive dairy farms,and dairy cows are individually different in the severity of SARA risk.The objectives of the current study were to investigate differences in the ruminal bacterial community and metabolome in dairy cattle with different susceptibility to SARA.In the present study,12 cows were initially enrolled in the experiment.Based on average ruminal pH,4 cows with the lowest ruminal pH were assigned to the susceptible group(SUS,pH=5.76,n=4)and 4 cows with the highest ruminal pH assigned to the tolerant group(TOL,pH=6.10,n=4).Rumen contents from susceptible(SUS,n=4)and tolerant(TOL,n=4)dairy cows were collected through rumen fistula to systematically reveal the rumen microbial and metabolic alterations of dairy cows with different susceptibility to SARA using multi-omics approaches(16S and 18S rRNA gene sequencing and metabolome).The results showed that despite being fed the same diet,SUS cows had lower ruminal pH and higher concentrations of total volatile fatty acids(VFA)and propionate than TOL cows(P<0.05).No significant differences were observed in dry matter intake,milk yield,and other milk compositions between the SUS and TOL groups(P>0.05).The principal coordinates analysis based on the analysis of molecular variance indicated a significant difference in bacterial composition between the two groups(P=0.01).More specifically,the relative abundance of starch-degrading bacteria(Prevotella spp.)was greater(P<0.05),while the proportion of fiber-degrading bacteria(unclassified Ruminococcaceae spp.,Ruminococcus spp.,Papillibacter,and unclassified Family_-XIII)was lower in the rumen of SUS cows compared with TOL cows(P<0.05).Community analysis of protozoa showed that there were no significant differences in the diversity,richness,and community structure(P>0.05).Metabolomics analysis revealed that the concentrations of organic acids(such as lactic acid),biogenic amines(such as histamine),and bacterial degradation products(such as hypoxanthine)were significantly higher in the SUS group compared to the TOL group(P<0.05).These findings revealed that the higher proportion of starch-degrading bacteria/lower fiber-degrading bacteria in the rumen of SUS cows resulted in higher VFA-producing capacity,in particular propionate.This caused a disruption in metabolic homeostasis in the rumen which might be the reason for the higher susceptibility to SARA.Overall,these findings enhanced our understanding of the ruminal microbiome and metabolic changes in cows susceptible to SARA.Tao Zhang Yingyu Mu Ruiyang Zhang Yanfeng Xue Changzheng Guo Wangpan Qi Jiyou Zhang Shengyong Mao 2022Animal Nutrition2022,,1:4
20High strain rate superplasticity of SiC whisker reinforced pure aluminum composites显示文摘A β SiC whisker reinforced pure aluminum composites expected to exhibit high strain rate superplasticity has been successfully fabricated by a new processing route consisting of pressure infiltration, extrusion with a low extrusion ratio and rolling. The composites exhibite a total elongation of 220%~380% in the initial strain rates within 1.0×10 -2 ~1.0×10 -1 s -1 and at 893~903 K. According to differential thermal analysis(DTA) and microstructure observation, it is concluded that an appropriately small amount of liquid phase is necessary to cause a good high strain rate superplasticity in aluminum matrix composites in addition to fine and uniform microstructure.Xu Xiaojing(许晓静) Zhao Changzheng(赵昌正) Zhang Di(张 荻) Shi Zhongliang(施忠良) Wu Renjie(吴人洁) 1999中国有色金属学会会刊:英文版1999,9,3:4
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