Veterinary Immunology and Immunopathology 141 (2011) 133–138
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Veterinary Immunology and
Immunopathology
j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /v e t i m
m
Short communication
Saccharomyces cerevisiae decreases in?ammatory responses induced by F4+enterotoxigenic Escherichia coli in porcine intestinal epithelial cells
Galliano Zanello a ,b ,1,Franc ?ois Meurens a ,1,Mustapha Berri a ,Claire Chevaleyre a ,Sandrine Melo a ,Eric Auclair b ,Henri Salmon a ,?
a Institut National de la Recherche Agronomique (INRA),UR1282,Infectiologie Animale et SantéPublique,F-37380Nouzilly (Tours),Indre et Loire,France b
SociétéIndustrielle Lesaffre,Lesaffre Feed Additives,Marcq-en-Baroeul,France
a r t i c l e i n f o Article history:
Received 19October 2010Received in revised form 13December 2010
Accepted 31January 2011Keywords:
Saccharomyces cerevisiae
Enterotoxigenic Escherichia coli Pig
Intestinal epithelial cells Cytokines Chemokines
a b s t r a c t
Probiotic yeasts may provide protection against intestinal in?ammation induced by enteric pathogens.In piglets,infection with F4+enterotoxigenic Escherichia coli (ETEC)leads to in?ammation,diarrhea and intestinal damage.In this study,we investigated whether the yeast strains Saccharomyces cerevisiae (Sc ,strain CNCM I-3856)and S.cerevisiae variety boulardii (Sb ,strain CNCM I-3799)decreased the expression of pro-in?ammatory cytokines and chemokines in intestinal epithelial IPI-2I cells cultured with F4+ETEC.Results showed that viable Sc inhibited the ETEC-induced TNF-?gene expression whereas Sb did not.In contrast,killed Sc failed to inhibit the expression of pro-in?ammatory genes.This inhibition was dependent on secreted soluble factors.Sc culture supernatant decreased the TNF-?,IL-1?,IL-6,IL-8,CXCL2and CCL20ETEC-induced mRNA.Furthermore,Sc culture supernatant ?ltrated fraction <10kDa displayed the same effects excepted for TNF-?.Thus,our results extended to Sc (strain CNCM I-3856)the inhibitory effects of some probiotic yeast strains onto in?ammation.
? 2011 Elsevier B.V. All rights reserved.
1.Introduction
Enterotoxigenic Escherichia coli (ETEC)are pathogenic gram negative bacteria which infect humans and sev-eral species of farm animals such as calves and pigs.ETEC interacts with intestinal epithelial cells,colonizes the small intestine and secretes enterotoxins such as the heat-labile enterotoxins (LT),the heat-stable enterotox-ins (STa and/or STb),and the enteroaggregative E .coli heat-stable enterotoxin 1(EAST1)(Nagy and Fekete,2005).In pigs,ETEC infection and enterotoxin secretions can induce intestinal in?ammation and diarrhea resulting in reduced growth rate,increased mortality and economic
?Corresponding author.Tel.:+33247427331;fax:+33247427779.E-mail addresses:salmon@tours.inra.fr ,henri.salmon@tours.inra.fr (H.Salmon).1
These authors contributed equally to this work.loss (Fairbrother et al.,2005).Moreover,F4+ETEC strain induce pro-in?ammatory response in intestinal epithe-lial cells (Devriendt et al.,2010).Administration of the yeast Saccharomyces cerevisiae variety boulardii (Sb )has been shown to protect pigs in reducing ETEC transloca-tion (Lessard et al.,2009).In vitro studies showed that Sb secretes soluble factors that decrease the expression of pro-in?ammatory cytokines induced by enteric pathogens (Zanello et al.,2009).However,to our knowledge,there is no in vitro data regarding the anti-in?ammatory effects of S.cerevisiae (Sc )secreted soluble factors.Sc and Sb are members of the same species but they differ geneti-cally,metabolically and physiologically (Edwards-Ingram et al.,2007;Hennequin et al.,2001).Thus,in this study,we assessed if the non-commensal and non-pathogenic yeasts Sc (strain CNCM I-3856)and Sb (strain CNCM I-3799)secreted factors allowing the down-regulation of pro-in?ammatory gene expression in intestinal epithe-lial cells cultured with F4+ETEC.Sc (strain CNCM I-3856)
0165-2427/$–see front matter ? 2011 Elsevier B.V. All rights reserved.doi:10.1016/j.vetimm.2011.01.018
134G.Zanello et al./Veterinary Immunology and Immunopathology141 (2011) 133–138
was selected since this yeast has been shown to decrease in?ammation in a mouse model of induced colitis(Foligne et al.,2010)suggesting that Sc may provide health bene?ts against enteritis.Sb(strain CNCM I-3799)was selected to identify if this yeast presented anti-in?ammatory effects as described for the previously studied Sb probiotic strain (Dalmasso et al.,2006;Martins et al.,2010).
2.Materials and methods
2.1.Cell,bacteria and yeast cultures
The porcine small intestine epithelial cell line IPI-2I (ECACC93100622)was transformed from epithelial ileal cells of an adult boar(SLAd/d haplotype)(Kaeffer et al., 1993).IPI-2I cells were cultured in DMEM cell culture medium as described previously(Meurens et al.,2009).
ETEC56190strain(K88ad,O8:K87:H19)was grown in Luria–Bertani(LB)medium containing1%tryptone,0.5% yeast extract,1%NaCl,pH7.After overnight incubation at 37?C with vigorous shaking,bacteria were diluted at1:400 in fresh LB and grown until midlog phase(～4h)for all experiments.
Active forms of Sc(strain CNCM I-3856)and Sb(strain CNCM I-3799)(CNCM:French National deposit Collection of Microorganism Cultures,Institut Pasteur,Paris,France) were provided dried by Lesaffre(SociétéIndustrielle Lesaf-fre,147rue Gabriel Péri,BP6027,Marcq-en-Baroeul cedex, France)at a concentration of1×1010yeasts/g.Yeasts were rehydrated in free-DMEM for45min,at30?C.For the different experiments,Sc and Sb concentrations were established by yeast coloration with methylene blue buffer (0.3g/L methylene blue,20g/L sodium citrate)and quan-ti?cation of viable yeasts by coloration exclusion.
2.2.Preparation of killed yeasts and yeast culture supernatants
Sc was killed by ten cycles of freezing/thawing in liquid nitrogen.Viability was controlled by methylene blue col-oration and mortality by exclusion.Sc freezing resulted in 100%of dead yeasts.
Sc culture supernatant(ScS)and Sb culture supernatant (SbS)were prepared as described previously with slight modi?cations(Chen et al.,2006).Yeasts were cultured overnight in DMEM cell culture medium with moder-ate shaking at37?C,and at an initial concentration of 7.5×108yeasts/L.To separate yeasts from the supernatant, the preparation was centrifuged at9000×g,for15min, at4?C,and then?ltered through a0.22?m pore?lter (Sartorius Stedim France)resulting in ScS.After a fur-ther?ltration through a10kDa cut-off?lter(Vivaspin20 centrifugal concentrator,Sigma–Aldrich),the resulting?l-trate was designated as Sc ultra?ltrate supernatant<10kDa (S<10kDa).
2.3.IPI-2I infection by ETEC
IPI-2I cells were seeded in6-well plates(Falcon)and cultured for48h until con?uence(～1×106cells/well). After3washes with DMEM medium,IPI-2I cells were incubated overnight with Sc or Sb(3×106yeasts/well) in4mL of both antibiotics and FCS-free DMEM.Then, ETEC(1×107CFU/well)was added for3h.The yeast concentration was chosen based on preliminary experi-ments indicating that this concentration was required to inhibit signi?cantly the ETEC-induced pro-in?ammatory gene expression.To investigate the effect of Sc viability,IPI-2I cells were pre-incubated overnight with killed Sc before ETEC addition.To evaluate the effects of supernatants, 4mL of ScS,S<10kDa or SbS were incubated simultane-ously with ETEC(1×107CFU/well)for3h.The culture supernatant contained the soluble factors produced by an overnight yeast culture at3×106yeasts/4mL.
2.4.Analysis of relative mRNA expression using quantitative real-time PCR
IPI-2I cells were lyzed with Trizol reagent(Invitrogen) and total RNA was isolated using RNeasy Mini Kit(Qia-gen).Reverse transcription and quantitative real-time PCR (RT-qPCR)were performed using cDNA synthesized as pre-viously described(Bruel et al.,2010).Real time assays were run on a Bio-Rad Chromo4(Bio-Rad).To minimize sample variations,we used high quality RNA which was assessed by calculating OD260/OD280(≈2)and by cap-illary electrophoresis(Agilent2100Bioanalyzer,Agilent Technologies,Inc.,Santa-Clara,USA).Samples were nor-malized internally using simultaneously the average cycle quanti?cation(Cq)of multiple reference genes.Hypoxan-thine PhosphoRibosyl-Transferase1(HPRT-1),Ribosomal Protein L19(RPL-19)and Hydroxymethylbilane syn-thase2(HMBS2)were used as reference genes given to their stability in porcine intestinal epithelial cells (Bruel et al.,2010;Meurens et al.,2009).Expression data are expressed as relative values after Genex macro analysis(Bio-Rad)(Vandesompele et al.,2002).Primer sequences and annealing temperatures of analyzed genes were reported previously(Bruel et al.,2010).
2.5.Statistical analysis
The comparison of the differences in mRNA relative expression was evaluated by one-way ANOVA and dif-ferences tested by non-parametric Dunnett’s test(using GraphPad Prism software version4.00,GraphPad Software Inc.,San Diego,CA,USA).Differences were considered sig-ni?cant when P<0.05.
3.Results and discussion
To identify if the yeasts Sc and Sb inhibit pro-in?ammatory cytokine and chemokine expressions in IPI-2I cells,we?rst assessed their ability to decrease the ETEC-induced TNF-?gene expression as a positive con-trol of inhibition.As shown in Fig.1,ETEC up-regulated between5and15folds the TNF-?gene expression in IPI-2I cells(P<0.01).IPI-2I cells were chosen in this study as a model for intestinal epithelial cells but in vitro adhe-sion assay displayed that the F4+ETEC strain56190did not adhere to IPI-2I cells(data not shown).This result sug-
G.Zanello et al./Veterinary Immunology and Immunopathology141 (2011) 133–138135
Fig.1.Effects of Sc and Sb on TNF-?gene expression in IPI-2I cells cultured with ETEC.(A)IPI-2I cells(1×106cells/well)were pre-incubated overnight with different concentrations of Sc(0.3-1-3×106yeasts/well)and then ETEC(1×107CFU/well)was added to the co-culture for3h in order to identify the yeast inhibitory effect on TNF-?gene expression.(B)and(C)IPI-2I cells(1×106cells/well)were pre-incubated overnight with either Sc or Sb(3×106 yeasts/well)and then ETEC(1×107CFU/well)was added to the co-culture for3h in order to compare the inhibitory effect on both yeasts on TNF-?gene expression.Data are presented as means of TNF-?mRNA relative expressions±SEM(n=6).Results are representative of3independent experiments. **P<0.01.
Fig.2.Effects of Sc viability on cytokine and chemokine mRNA expressions in IPI-2I cells cultured with ETEC.IPI-2I cells(1×106cells/well)were pre-incubated overnight with killed Sc(3×106yeasts/well)and then ETEC(1×107CFU/well)was added to the co-culture for3h.Data are presented as means of mRNA relative expressions±SEM(n=5).**P<0.01.
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141 (2011) 133–138
Fig.3.Effects of the Sc culture supernatant (ScS )and the ultra?ltrated fraction (S <10kDa)on cytokine and chemokine mRNA expressions in IPI-2I cells cultured with ETEC.IPI-2I cells (1×106cells/well)were cultured with (A)ScS or (B)S <10kDa simultaneously with ETEC (1×107CFU/well)for 3h.Data are presented as means of mRNA relative expressions ±SEM (n =5).Results are representative of 2independent experiments.**P <0.01.In each graph,IPI-2I cells exposure to ETEC increased signi?cantly mRNA levels of cytokines and chemokines as compared to medium but no sign of signi?cance (asterisk)was added.
gested that the up-regulation of TNF-?mRNA level could be due to bacterial constituents like LPS or ?agellin (Devriendt et al.,2010).TNF-?up-regulation was signi?cantly inhib-ited (÷4.4,P <0.01,Fig.1A)by Sc at the ratio of 3yeasts/https://www.doczj.com/doc/0e4722387.html,parison of yeast effects at this ratio indicated that Sc inhibited TNF-?mRNA expression (÷5,P <0.01,Fig.1B)whereas Sb did not (Fig.1C).These results were reminis-cent of a similar TNF-?reduction by Sb probiotic strain in T84colonocytes infected with an enterohemorrhagic E.coli (EHEC)(Dalmasso et al.,2006).
Then,we investigated if Sc inhibitory effects on pro-in?ammatory gene expression were due to yeast-secreted factors.We assessed the effect of yeast viability and IPI-2I cells were co-cultured with both killed Sc and ETEC (Fig.2).The levels of TNF-?,IL-1?,IL-6,IL-8,CXCL2and CCL20tran-scripts were analyzed.Co-culture of IPI-2I cells with ETEC alone for 3h up-regulated the mRNA levels of TNF-?(×6),CCL20(×5),IL-6and CXCL2(×3.7),IL-1?(×3.2)and IL-8(×3)(Fig.2)whereas adjunction of killed Sc failed to inhibit the expression of these genes (Fig.2).Furthermore,IL-6and IL-8mRNA levels were up-regulated in presence of killed Sc (×2.1and ×1.8respectively),probably due to yeast wall structures such as ?-glucans (Sonck et al.,2010).
IPI-2I cells were next cultured with both yeast culture supernatants and ETEC in order to identify if Sc -secreted factors had inhibitory effects on pro-in?ammatory cytokine and chemokine expressions.ScS inhibited the ETEC-induced mRNA levels of IL-8(÷5),CCL20(÷4.9),IL-6(÷4.7),TNF-?(÷4.3),CXCL2(÷3.5)and IL-1?(÷2.8)suggesting the presence of one or several anti-in?ammatory factors (Fig.3A).To identify if Sc -secreted anti-in?ammatory factors were smaller than 10kDa as described for Sb probiotic strain (Sougioultzis et al.,2006),IPI-2I cells were co-cultured with both the S <10kDa
G.Zanello et al./Veterinary Immunology and Immunopathology141 (2011) 133–138
137
Fig.4.Effects of Sb culture supernatant(SbS)on cytokine and chemokine mRNA expressions in IPI-2I cells cultured with ETEC.IPI-2I cells(1×106cells/well) were cultured with SbS simultaneously with ETEC(1×107CFU/well)for3h.Data are presented as means of mRNA relative expressions±SEM(n=6). **P<0.01.
fraction and ETEC.The S<10kDa fraction inhibited the ETEC-induced CXCL2(÷5.6),IL-6(÷5.5),CCL20(÷4.1),IL-1?(÷4)and IL-8(÷3.4)expressions showing that soluble factors<10kDa inhibited pro-in?ammatory gene expres-sions,excepted for TNF-?(Fig.3B).In contrast,SbS was used as control and did not inhibit the ETEC-induced pro-in?ammatory gene expression as described for TNF-?and IL-8(Fig.4).In the current work,Sc anti-in?ammatory effects have not been evaluated at the protein level.How-ever,the inhibition of transcript expression observed for a cluster of pro-in?ammatory genes strongly suggests Sc effectiveness in the inhibition of the related protein productions.Indeed,the yeast inhibition of IL-8tran-script has been previously shown to correlate with the decrease of protein production(Martins et al.,2010). These inhibitory effects were in accordance with sev-eral studies reporting that the culture supernatant of Sb probiotic strain down-regulated the expression of pro-in?ammatory cytokine such as IL-8(Chen et al.,2006; Mumy et al.,2007).Moreover,this down-regulation was dependent of mitogen-activated protein kinase(ERK1/2, p38,JNK)and/or NF-?B inhibition(Chen et al.,2006; Martins et al.,2010;Mumy et al.,2007)suggesting that Sc-secreted factors could interfere with pro-in?ammatory signalling pathways in IPI-2I cells.In addition,the anti-in?ammatory effects of Sb probiotic strain were correlated with a decrease in intestinal damage caused by enteric pathogen such as Salmonella enterica serovar Typhimurium (Martins et al.,2010).Overall,these data suggested that Sc (strain CNCM I-3856)may be administrated as probiotic yeast to prevent intestinal damage caused by ETEC in?am-mation.In contrast,Sb(strain CNCM I-3799)did not display inhibitory effects on cytokine and chemokine expressions. These results were different from those observed with the previously studied Sb probiotic strain and indicated that anti-in?ammatory effects onto intestinal epithelial cells were strain dependent.Thus,this study showed that regulation of in?ammatory gene expression was not a mechanism speci?c of all Sb strains and displayed that Sc (non boulardii)yeasts can induce this effect despite their genetic,metabolic and physiologic differences.
In conclusion,we reported in this study that Sc-secreted factors inhibit the expression of pro-in?ammatory cytokines and chemokines induced by ETEC as described for Sb probiotic strain.These data suggest that Sc may protect the gut against intestinal damage caused by pathogen-associated in?ammation in piglets and represent a?rst step in the better understanding of Sc immuno-regulatory effects in infectious and in?ammatory diseases. Acknowledgements
G.Zanello was supported by a Ph.D.grant from SociétéIndustrielle Lesaffre and the French Government.We gratefully acknowledge P.Vandekerckove and G.Pignède (Lesaffre)for their assistance in this work.We thank Dr.
C.Martin(Institut National de la Recherche Agronomique, Clermont-Theix,France)for kindly providing the F4+ETEC strain56190.
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11,47–58.
PCB 专业术语中英文翻译 很多PCB 的书上使用的是英文，但是大多数的人又看不懂英文， 这时候怎么办呢，我们需要翻译，但是如果每看到一个不会的词 儿就去翻译，那么就太耗费时间了，所以我们捷多邦总结了一些 常用的专业术语的中英文对照，希望能对大家有用。 1.印制电路：printed circuit 2.印制线路：printed wiring 3.印制板：printed board 4.印制板电路：printed circuit board (pcb) 5.印制线路板：printed wiring board(pwb) 6.印制元件：printed component 7.印制接点：printed contact 8.印制板装配：printed board assembly 9.板：board 1 10.表面层合电路板：surface laminar circuit (slc) 11.埋入凸块连印制板：b2it printed board 12.多层膜基板：multi-layered film substrate(mfs) 13.层间全内导通多层印制板：alivh multilayer printed board 14.载芯片板：chip on board (cob) 15.埋电阻板：buried resistance board 16.母板：mother board 17.单面印制板：single-sided printed board(ssb) 、管路敷设技术通过管线不仅可以解决吊顶层配置不规范高中资料试卷问题，而且可保障各类管路习题到位。在管路敷设过程中，要加强看护关于管路高中资料试卷连接管口处理高中资料试卷弯扁度固定盒位置保护层防腐跨接地线弯曲半径标等，要求技术交底。管线敷设技术中包含线槽、管架等多项方式，为解决高中语文电气课件中管壁薄、接口不严等问题，合理利用管线敷设技术。线缆敷设原则：在分线盒处，当不同电压回路交叉时，应采用金属隔板进行隔开处理；同一线槽内强电回路须同时切断习题电源，线缆敷设完毕，要进行检查和检测处理。、电气课件中调试对全部高中资料试卷电气设备，在安装过程中以及安装结束后进行 高中资料试卷调整试验；通电检查所有设备高中资料试卷相互作用与相互关系，根据生产工艺高中资料试卷要求，对电气设备进行空载与带负荷下高中资料试卷调控试验；对设备进行调整使其在正常工况下与过度工作下都可以正常工作；对于继电保护进行整核对定值，审核与校对图纸，编写复杂设备与装置高中资料试卷调试方案，编写重要设备高中资料试卷试验方案以及系统启动方案；对整套启动过程中高中资料试卷电气设备进行调试工作并且进行过关运行高中资料试卷技术指导。对于调试过程中高中资料试卷技术问题，作为调试人员，需要在事前掌握图纸资料、设备制造厂家出具高中资料试卷试验报告与相关技术资料，并且了解现场设备高中资料试卷布置情况与有关高中资料试卷电气系统接线等情况 ，然后根据规范与规程规定，制定设备调试高中资料试、电气设备调试高中资料试卷技术电力保护装置调试技术，电力保护高中资料试卷配置技术是指机组在进行继电保护高中资料试卷总体配置时，需要在最大限度内来确保机组高中资料试卷安全，并且尽可能地缩小故障高中资料试卷破坏范围，或者对某些异常高中资料试卷工况进行自动处理，尤其要避免错误高中资料试卷保护装置动作，并且拒绝动作，来避免不必要高中资料试卷突然停机。因此，电力高中资料试卷保护装置调试技术，要求电力保护装置做到准确灵活。对于差动保护装置高中资料试卷调试技术是指发电机一变压器组在发生内部故障时，需要进行外部电源高中资料试卷切除从而采用高中资料试卷主要保护装置。
M1U1 托尼：呣…..好香啊。你做的比萨看上去不错。 贝蒂：谢谢！来一点尝尝？ 托尼：好的。看上去不错，闻起来香喷喷的，呣，好吃。 大明：这上面是什么？ 贝蒂：噢，是奶酪，想尝一块吗？ 大明：啊！不用了，谢谢，我不喜欢奶酪。奶酪闻起来不新鲜，气味太大，吃起来有点酸。 贝蒂：嗯，我的巧克力饼干做好了，尝尝吧！ 大明：谢谢！很甜，里面很酥软。 托尼：你是不是在做很多不同的食物啊？你看上去挺忙的！ 贝蒂：是的。我做了比萨和饼干，现在我在做苹果派和蛋糕。 大明：苹果派听起来不错呢。我喜欢甜食，你知道的。我给你拿糖吧？ 贝蒂：好。噢，你确定你拿的是糖吗？先尝一下，可能是盐。 大明：没拿错，是甜的，是糖。 托尼：这是什么？也是甜的。 贝蒂：是草莓酱，做蛋糕用的。 大明：太好了。每种东西都是甜丝丝的。我今天可真幸运啊！ M1U2 玲玲： 你好！ 谢谢你上次的来信，收到你的信真是太好了。真想马上见到你。 希望你能凭着照片在机场认出我来。我的个子比较高，留着一头金色短发，戴眼镜。为了旅行方便，我将穿牛仔裤和T恤，但我也会拿一件厚点的外套。我这里有你的照片，你非常漂亮，我想我们肯定能认出对方来！ 谢谢你告诉我你的爱好，我俩的爱好非常相似！我花很多时间在学校和朋友弹奏古典音乐，我也喜欢舞曲——我喜欢跳舞。我也喜欢运动，尤其是网球。我哥哥在我们学校网球队，我为他感到非常自豪。他各方面都很优秀，而我不行。有时候考得不好，我会难过。我要更加努力。 你问我：“要来中国了，你有什么感受？”嗯，每当我要离开父母几天时，起初都会有点感伤。和陌生人一起的时候，我会很害羞，讲汉语时我会感到紧张，但是过几天就好了。当我不知道该如何正确处理事情时，心里总是难过，所以到中国和你在一起的时候，你要帮助我哟！对了，我还害怕做飞机。不过要去中国了，你不知道我有多兴奋！ 下周见！ 爱你的， 萨莉
Exploring Filipino School Counselors’ Beliefs about Learning Allan B. I. Bernardo [Abstract] School reform efforts that focus on student learning require school counselors to take on important new roles as advocates of student learning and achievement.But how do school counselors understand the process of learning? In this study, we explore the learning beliefs of 115 Filipino school counselors who indicated their degree of agreementwith 42 statements about the process of learning and the factors thatinfluence this process.A principal components analysis of the responses to the 42 statements suggested three factors:(F1)social-cognitive constructivist beliefs, (F2) teacher-curriculum-centered behaviorist beliefs,and (F3) individual difference factors.The preliminary results are briefly discussed in terms of issues related to how Filipino school counselors’ conceptions of learning may guide their strategies for promoting student learning and achievement. [Key words]beliefs about learning, conceptions of learning, school counselors, student learning, Philippines School reform efforts in different parts of the world have focusedon students’learning. In particular,most school improvement programsnow aim to ensure that students acquire the high-level knowledge and skills that help them to thrive in today’s highly competitive globaleconomy (e.g., Lee & Williams, 2006). I n this regard, school reform programs draw from various contemporary theories and research on learning (e.g.,Bransford,Brown, & Cocking, 1999; Lambert & McCombs, 1998).The basic idea is that all school improvement efforts should be directed at ensuring students achieve high levels of learning or attainment of well-defined curricular objectives and standards.For example, textbooks (Chien & Young, 2007), computers and educational technology (Gravoso, 2002; Haertnel & Means, 2003;Technology in Schools Task Force, 2003), and educational assessment systems (Black & Wiliam2004; Cheung & Ng, 2007; Clark, 2001; Stiggins, 2005) are being reconsidered as regards how they can effectively provide scaffolds and resources for advancing student learning. Likewise,the allocation and management of a school’s financial resources are assessed in terms ofwhether these are effectively mobilized and utilized towards improving student learning (Bolam, 2006; Chung & Hung, 2006; Retna, 2007). In this regard, some advocates have also called for an examination of the role of school counselors in these reform efforts (Herr, 2002). Inthe United States, House and Hayes (2002) challenged school counselors to take proactive leadership roles in advocating for the success of all
英译汉几个常见问题如下： 1）英译汉时语言组织不符合中文的讲话习惯。在不改变原文绝大部分意思的情况下，不需要字对字或者严格遵守英语语序，在获得原句含意后务必采用中文的思维将译文写出。要求是在读着看过译文后，不能让读着感觉到文章是翻译而得的，即不能留有丝毫翻译的痕迹。 2）英译汉时译文上下文的用词不一致。尤其是学术文献或论文的翻译，除了学术用语和专业用语需要准确，更重要的是全文上下文中同一个词或者短句翻译出的用词或短语必须一致。例如一开始将control panel翻译为“控制面板”，那么全文都不得改变这个译法。 3）英译汉时用词过于口语化。除了剧本，台词，字幕等需要口语化用词的翻译稿件以外。其余大部分翻译，例如文献，论文，合同，申请书，标书等，用词尽量书面化。例如“weight”在统计学和分析学中不可翻译为“给予数值”，必须翻译为“赋权”，两者意思相近，但是采用后者。 4）英译汉时词汇含意理解产生偏差。这是死记单词造成的后果。翻译中，在无上下文的情况下，除非是专有学术名词（例“diabetes”基本上永远都是糖尿病的意思），其余的单词很难说究竟是什么意思，我们只能说某个词大概是对照中文某个词的感觉，但是决不可死认一个意思，死认单词意思造成翻译不通、翻译错误等。当然也不能糊译，不能为了使句子翻译通顺而胡编一个意思。 5）英译汉时英语长句中的意群划分有误。原版的英语资料中长句较多，往往40-50个词之间没有一个标点，修饰成分和意群划分的错误会导致理解错误和翻译错误。原则上，英语中的各类从句，特别是状语从句在句子中的位置相对灵活，没搞明白其修饰对象就会错译。 汉译英几个常见问题如下： 1）汉译英时字对字翻译。这是翻译中最致命的错误，很多人以为认识对应的英语单词或者知道对应的英语单词，这句话才会翻译。其实不是，原则上四千词汇量就能解释大部分英语单词的含义，只不过大部分人不知道如何用简单词汇造句去描述或解释高难度单词。 2）汉译英时中式语序。何谓中式语序，即以“主+谓+宾”为主的句型。这种句子写多了，一旦遇上长句或者语法功能上缺少成分的句子就懵了。所以必须多读，多了解原版英语的句子是如何写的。 3）汉译英时短句太多。这里并不是指写英语短句不好，在考试中建议写短句，这是为了避免语法错误，当然也不要太短了。在较为正式的或专业性强的文本中，汉译英在必要时需要翻译成长句。例如不久前的某论文中的一句：筛选出对靶基因干扰效率最高的 HER2-shRNA慢病毒表达载体并成功包装成病毒去感染SKOV-3细胞而后在体外进行实验的结果显示Her2/neu的siRNA慢病毒载体可以显著抑制靶基因的表达并使卵巢癌SKOV3细胞的生物学行为明显受抑。因此，熟练掌握各类从句的写法和作用很重要。 4）汉译英时英语词汇词义辨析不清而导致误用，用词不准。大部分人的翻译习惯是，凡是中文有英文的对应单词，就二话不说直接用，其实这个是不对的。很多同义词意思相近，用法和所用的语境场合完全不同。例如“base”“basis”“foundation”，意思几乎相同，但是用法完全不同。尤其是学术文章，误用就导致歧义。 5）汉译英时逻辑混乱结构不清。汉译英中的逻辑和语句结构相当重要。逻辑混乱，即译文毫无章法，思绪混沌，不知所云。结构不清，即英语的从句或其他成分在句中的位置胡乱摆放，进行翻译的人员自然是清楚的指导这些英语句子的含义，因为是看着中文翻译过来的，想不知道中文含义都难，但是没看过中文的读着就会因此而看得云里雾里，从而导致读者难以理解译文。
工程建设标准英文版翻译细则 （试行） 为规范工程建设标准英文版的翻译工作，根据《工程建设标准翻译出版工作管理办法》，制定本细则。 1 翻译质量及技术要求 1.1 基本要求 1）工程建设标准的翻译必须忠于原文，并遵守完整、准确、规范、统一的原则。 2）标准的译文应当完整。标准的前引部分、正文部分、补充部分都应全文翻译；脚注、附录、图、表、公式以及相应的文字都应翻译并完整地反映在译文中，不得误译、缺译、漏译、跳译。 3）强制性条文的翻译必须准确无误，译文用黑体字注明。 4）译文的内容、术语应当准确，语法应当恰当，行文流畅。 5）标准中的典型语句、术语、计量单位、专业词汇应当前后统一。 6）标准翻译稿的幅面、版面、格式、字体等应当规范并符合《工程建设标准英文版出版印刷规定》，图表、公式的编号应与原文相一致。
1.2 具体要求 1）数字表达应符合英文表达习惯。 2）标准中的符号、代号、计量单位、公式应直接引用原文，时间、货币、标点符号可按英文惯例翻译或表达。 3）日期按译文语言，应采用公历，按月、日、年顺序排列（例如，December 1,2006）。 4）术语的英文翻译，应以中文版中的英文术语为准。如果中文版中英文术语表达不准确或出现错误，应由翻译人员与编制组共同商议后做出必要修正，并在译文中注明。 5）标准名称应以中文版的英文译名为准。如果中文版标准名称的英文译文不准确，翻译人员可向翻译出版办公室提出书面修改建议。 6）人员的中文姓名译成英文时，采用标准汉语拼音。外籍人员的姓名应按其原姓名或相应的英文姓名表达。地名、团体名、机构名，使用惯用译名。无惯用译名的，可自行翻译，必要时附注原文。 7）法律、法规、规范性文件等名称应采用官方或既定译法，其他文件、著作、文献名称采用既定译法。 8）缩写词首次出现时,应附注全称译文。经前文注释过或意义明确的缩写词，可以在译文中直接使用。 9）译文的章节条款项的编号，应与中文版一致。
高速视频处理系统中的信号完整性分析 摘要：结合高速DSP图像处理系统讨论了高速数字电路中的信号完整性问题，分析了系统中信号反射、串扰、地弹等现象破坏信号完整性的原因，通过先进IS工具的辅助设计，找出了确保系统信号完整性的具体方法。 关键词：高速电路设计信号完整性 DSP系统 深亚微米工艺在IC设计中的使用使得芯片的集成规模更大、体积越来越小、引脚数越来越多；由于近年来IC工艺的发展，使得其速度越来越高。从而，使得信号完整性问题引起电子设计者广泛关注。 在视频处理系统中，多维并行输入输出信号的频率一般都在百兆赫兹以上，而且对时序的要求也非常严格。本文以DSP图像处理系统为背景，对信号完整性进行准确的理论分析，对信号完整性涉及的典型问题[1]——不确定状态、传输线效应、反射、串扰、地弹等进行深入研究，并且从实际系统入手，利用IS仿真软件寻找有效的途径，解决系统的信号完整性问题。 1 系统简介 为了提高算法效率，实时处理图像信息，本图像处理系统是基于DSP+FPGA结构设计的。系统由SAA7111A视频解码器、TI公司的TMS320C6701 DSP、Altera公司的EPlK50QC208 FPGA、PCI9054 PCI接口控制器以及SBRAM、SDRAM、FIFO、FLASH等构成。FPGA是整个系统的时序控制中心和数据交换的桥梁，而且能够对图像数据实现快速底层处理。DSP是整个系统实时处理高级算法的核心器件。系统结构框图如图1所示。 在整个系统中，PCB电路板的面积仅为15cm×l5cm，系统时钟频率高达167MHz，时钟沿时间为0．6ns。由于系统具有快斜率瞬变和极高的工作频率以及很大的电路密度，使得如何处理高速信号问题成为一个制约设计成功的关键因素。 2 系统中信号完整性问题及解决方案 2．1 信号完整性问题产生机理 信号的完整性是指信号通过物理电路传输后，信号接收端看到的波形与信号发送端发送的波形在容许的误差范围内保持一致，并且空间邻近的传输信号间的相互影响也在容许的范围之内。因此，信号完整性分析的主要目标是保证高速数字信号可靠的传输。实际信号总是存在电压的波动，如图2所示。在A、B两点由于过冲和振铃[2]的存在使信号振幅落入阴影部分的不确定区，可能会导致错误的逻辑电平发生。总线信号传输的情况更加复杂，任何一个信号发生相位上的超前或滞后都可能使总线上数据出错，如图3所示。图中，CLK为时钟信号，D0、D1、D2、D3是数据总线上的信号，系统允许信号最大的建立时间[1]为△t。在正常情况下，D0、D1、D2、D3信号建立时间△t1<△t，在△t时刻之后数据总线的数据已稳定，系统可以从总线上采样到正确的数据，如图3(a)所示。相反，当信号D1、D2、D3受过冲和振铃等信号完整问题干扰时，总线信号就发生
市场营销专业术语中英文对照标准翻译 本文为市场营销中经常用到的一些中文与英文互译的标准用语，希望对市场营销从业人员有所帮助。 《财富》杂志Fortune 案头调研Desk Research 奥美公司Ogilvy & Mather 白色商品White Goods 百乐门Parliament 百威啤酒Budweiser 包裹销售法Banded Pack 宝洁公司Procter & Gamble 宝丽来Polaroid 宝马BMW 边际成本Marginal Cost 边际收益Marginal Benefit 标准差，均差Standard Deviation 别克Buick 波立兹调查公司Alfred Politz Research, Inc 波旁王朝Ancient Age Bourbon 波特福洛分析Portefolio Analysis 产品差异Product Differentiation 产品生命周期Product Life Cycle 产品系列Product Line 产品组合Product Mix 阐述Presentation 超级市场Supermarket 成对比较法Paired Comparisons 成功的理想主义者Successful Idealist 承诺型消费者Committed Buyer 程度测试Tachistoscope 橙色商品Orange Goods 冲动购买Impulse Buying 重叠率Duplication 抽样Sampling 传销Pyramid Selling 传阅发行量Pass-on Circulation 词语联想法Word Associaton 刺激营销Incentive Marketing 促销Promotion 达彼思广告公司Ted Bates & Copany 大卫·奥格威David Ogilvy 戴比尔斯De Beers
GRA VITY RETAINING?WALL 1. INTRODUCTION Retaining walls are structures used to provide stability for earth or other material where conditions disallow the mass to assume its natural slope, and are commonly used to hold back or support soilbanks,coal or ore piles, and water. Retaining walls are classified, based on the method of achieving stability, into six principal types (Fig.1). The gravity-wall depends upon its weight, as the name implies, for stability. The cantilever wall is a reinforced-concrete wall that utilizes cantilever action to retain the mass behind the wall from assuming a natural slope. Stability of this wall is partially achieved from the weight of soil on the heel portion of the base slab. A counterfort retaining wall is similar to a cantilever retaining wall, except that it is used where the cantilever is long or for very high pressures behind wall and has counterforts, which tie the wall and base together, built at intervals along the wall to reduce the bending moments and sheers. As indicated in Fig.1c, the counterfort is behind the wall and subjected to tensile forces. A buttressed retaining wall is similar to a counterfort wall, except that the bracing is in front of the wall and is in compression instead of tension. Two other types of walls not considered further are crib walls, which are built-up members of pieces of precast concrete, metal, or timber and are supported by anchor pieces embedded in the soil for stability, and semigravity walls, which are walls intermediate between a true gravity and a cantilever wall. (a)(b)(e)
英语专八考试翻译评分标准 英译汉评分标准：按照“忠实60% + 通顺40%”的标准整体打分 优秀 （100-90）良好（89-90）中等（79-70）及格（69-60） 不及格（59分 以下） 忠实60% 原文的信息全 部传达，语气 和文体风格与 原文一致 除个别次要信息有 疏漏之外，原文的 重要信息全部传 达，语气和文体风 格与原文一致 有少量理解错误 或个别漏译，但主 要精神与原文一 致 有个别重大错误或 遗漏，部分信息含 混，但总体上基本 达意 误译、漏译较 多，不能传达 原文主要精神 通顺40% 断句恰当，句 式正确。选词 妥帖。段落之 间、句子之间 互应自然，有 一定文采 选词较正确、得体。 句子组织与安排符 合汉语规范 拘泥于英文的句 式，行文不够顺 达，但没有重大的 选词和句式错误 语句不够连贯，行 文灰色，有个别重 大的选词和句式错 误 用词不当，行 文不通顺，语 言不符合汉语 规范 汉译英评分标准：按照“忠实60% + 通顺40%”的标准整体打分 优秀（100-90）良好（89-90）中等（79-70）及格（69-60）不及格（59分以下） 忠实60% 原文的信息全部 传达，语气和文 体风格与原文一 致 除个别次要信息 有疏漏之外，原文 的重要信息全部 传达，语气和文体 风格与原文一致 有少量理解错 误或个别漏译， 但主要精神与 原文一致 有个别重大错 误或遗漏，部分 信息含混，但总 体上基本达意 误译、漏译较 多，不能传达 原文主要精 神 通顺40% 句式处理恰当， 选词妥帖，英语 比较地道 语言基本合乎英 语规范。行文比较 流畅 有个别句子结 构错误和词不 达意现象。行文 不够流畅 有逐字硬译，不 符合英语表达 习惯的现象。句 子不连贯，比较 费解 有大量的语 法和用词错 误。1/3以上 的句子生搬 硬套，不知所 云
文档简介 一，英语翻译经典文章之英文原稿二，中文翻译：这篇英语文章的最好翻译版本！不是俺说的，是俺老师说哒！！ 英文原稿Brian It seems my only request (“please, let me sleep”) is not clear enough, so I made this simple table that can help you when you’re in doubt. Especially during the night
中文翻译小子： 我只想好好地睡觉，你不明白吗？！所以，我做了这个简表。当你不知道怎么办时，特 别是在晚上的时候，你可以看看它。 具体情况行动指南 1，我正在睡觉禁止进入 2，你不确定我是否睡觉，你想搞清楚管你“鸟”事；禁止进入 3，你嗑了药，想奔向我的床你他妈的滚远点 4，你在youtube上看了一个超赞的视频，禁止进入；在脸书上把链接发给我想让我看看 5，就算第三次世界大战开始了管我屁事，他妈的别进来 6，你和你的基友们想和我“玩玩”抱歉，直男一枚。不要碰我的任何东西，门都别碰 7，你想整理我的房间我谢谢你了！我自己会打扫 8，普京宣布同性婚姻合法化终于等到“它”！还好你没放弃！还是不要来我房里！ 9，我不在家进我房间，想都别想 10，白天，我在家。你敲了门，我说“请进” 你可以进来了 福利放送！！
如果你已经看到了这里，那么说明你应该是英文爱好者哦。 下面有一些非常实用，我精心整理的英文资料，你一定用得到！快去看看吧！ 一，最常用英语翻译政治文体句型总结大全完美版 二，英文合同翻译最常用句型总结专业版 三，英语毕业论文提纲模板优秀完整详细无敌版
预约券reservation ticket 下午茶high tea 微博Microblog/ Tweets 裸婚naked wedding 亚健康sub-health 平角裤boxers 愤青young cynic 灵魂伴侣soul mate 小白脸toy boy 精神出轨soul infidelity 人肉搜索flesh search 剩女3S lady（single，seventies,stuck）/left girls 山寨copycat 异地恋long-distance relationship 性感妈妈yummy mummy 钻石王老五diamond bachelor 时尚达人fashion icon 上相的,上镜头的photogenic 学术界academic circle 哈证族certificate maniac 偶像派idol type 住房公积金housing funds 熟女cougar（源自电影Cougar Club） 挑食者picky-eater 伪球迷fake fans 紧身服straitjacket 团购group buying 奉子成婚shotgun marriage 婚前性行为premarital sex 炫富flaunt wealth 决堤breaching of the dike 上市list share 赌球soccer gambling 桑拿天sauna weather 自杀Dutch act 假发票fake invoice 金砖四国BRIC countries 笑料laughing stock 泰国香米Thai fragrant rice 学历造假fabricate academic credentials 泄洪release flood waters 狂热的gaga eg: I was gaga over his deep blue eyes when I first set eyes on him 防暑降温补贴high temperature subsidy 暗淡前景bleak prospects
南京师范大学泰州学院 英文翻译原文 年级： 2011级学号：12110330 姓名：申佳佳 系部：信息工程学院 专业：通信工程 题目：基于C51的数字测速仪设计与仿真 指导教师：焦蓬蓬 2015 年 4 月 5 日
Linux - Operating system of cybertimes Though for a lot of people , regard Linux as the main operating system to make u p huge work station group, finish special effects of " Titanic " make , already can be re garded as and show talent fully. But for Linux, this only numerous news one of. Rece ntly, the manufacturers concerned have announced that support the news of Linux to i ncrease day by day, users' enthusiasm to Linux runs high unprecedentedly too. Then, Linux only have operating system not free more than on earth on 7 year this piece wh at glamour, get the favors of such numerous important software and hardware manufa cturers as the masses of users and Orac le , Informix , HP , Sybase , Corel , Intel , Net scape , Dell ,etc. , OK? 1.The background of Linux and characteristic Linux is a kind of " free (Free ) software ": What is called free, mean users can o btain the procedure and source code freely , and can use them freely , including revise or copy etc.. It is a result of cybertimes, numerous technical staff finish its research a nd development together through Inte rnet, countless user is it test and except fault , c an add user expansion function that oneself make conveniently to participate in. As th e most outstanding one in free software, Linux has characteristic o f the following: (1)Totally follow POSLX standard, expand the network operating system of sup porting all AT&T and BSD Unix characteristic. Because of inheritting Unix outstandi ng design philosophy , and there are clean , stalwart , high-efficient and steady kernels , their all key codes are finished by Li nus Torvalds and other outstanding programmer s, without any Unix code of AT&T or Berkeley, so Linu x is not Unix, but Linux and Unix are totally compatible. (2)Real many tasks, multi-user's system, the built-in n etwork supports, can be with such seamless links as NetWare , Windows NT , OS/2 , Unix ,etc.. Network in various kinds of Unix it tests to be fastest in comparing and ass ess efficiency. Support such many kinds of files systems as FAT16 , FAT32 , NTFS , E x t2FS , ISO9600 ,etc. at the same time .
专业英语的翻译技巧 一、概论 1.翻译的标准 我国清末翻译家严复认为翻译的标准：信、达、雅。所谓“信”，就是忠实原作，不任意曲解；所谓“达”，即通顺，流畅；而“雅”，则是文字优美，高雅。由于专业英语本身注重表现技术问题的科学性、逻辑性、正确性和严密性，所以，专业英语的翻译标准更侧重于“信”和“达”（或“顺”）。 【例】The importance of building modern road can not be overestimated in the economic development. 在经济发展中，修建现代化道路的重要性无论怎么估计也不过分。 【例】A novel solution to car which runs out of control into bridge abutments and the like has become popular in North America although not yet in Europe. 对于如何避免汽车在失去控制时撞到墩柱上或别的类似的物体上，已经有了一种新的解决办法。这种办法在北美已普遍使用，然而在欧洲却未能做到这一点。 【例】Grouting of the tendons usually follows the freedom of the ducts from obstruction. 钢束灌浆之前，孔道应畅通无阻。 2.翻译的过程 （1）阅读理解 阅读理解阶段应注意：一是正确地理解原文的词汇含义、句法结构和习惯用法，二是要准确地理解原文的逻辑关系。 【例】Pavement are classified as “rigid” or “flexible”,depending on how they distribute surface loads. 按照传递表面荷载情况，路面可分为“刚性的”或“柔性的”。 （2）汉语表达 表达阶段的任务就是译者根据其对原文的理解，使用汉语的语言形式恰如其分地表达原作的内容。 【例】Action is equal to reaction, but it acts in a contrary direction.
Basic Control Actions and Industrial Automatic Control An automatic controller compares the actual value of the plant output with the desired value, determines the deviation, and produces a control signal which will reduce the deviation to zero or to a small value.The manner in which the automatic conroller produces the control signal is called the control action. Classifications of industrial automatic controllers Induetrial automatic controllers may be classified according to their control action as: ·two-position or on-off controllers; ·proportional controllers; ·integral controllers; ·proportional-plus-integral controllers; ·proportional-plus-derivative controllers; ·proportional-plus-derivative-plus-integral controllers. Most industrial automatic controllers use eletricity or pressurized fluid such as oil or air as power sources. Automatic controllers may also be classified according to the kind of power employed in the operation, such as pneumatic controllers, hydraulic controllers, or electronic controllers.What kind of controller to use must be decided by the nature of the plant and the operating conditions,including such considerations as safety, availability, reliability, accuracy, weight, and size? Elements of industrial automatic controllers An automatic controller must detect the actuating error signal, which is usually at a very low power level, and amplify it to a sufficiently high level. Thus, an amplifier is necessary. The output of an automatic controller is fed to a power device, such as a pneumatic motor or valve, a hydraulic motor, or an electric motor. The controller usually consists of an error detector and amplifier. The measuring element is a device that converts the output variable into another suitable variable, such as a displacement, pressure, or electric signal, which can be used for comparing the output to the reference input signal. This element is in the feedback path of the closed-loop system. The set point of the controller must be converted to a reference input of the same units as the feedback signal from the measuring element. The amplifier amplifies the power of the actuating error signal, which in turn operates the actuator. The actuator is an element which alters the input to the plant according to the control signal so that the feedback signal may be brought into correspondence with the reference input signal. Self-operated controllers In most industrial automatic controllers, separate units are used for the measuring element and for the actuator. In a very simple one, however, such as a self-operated controller, these elements are assembled in one unit. Self-operated controllers utilize power developed by the measuring element and are very simple and inexpensive. The set point is determined by the adjustment of the spring force. The controlled pressure is measured by the diaphragm. The actuating error signal is the net force acting on the diaphragm. Its position determines the valve opening. The operation of self-operated controller is as follows: Suppose that the output pressure is lower than the reference pressure, as determined by the set point. Then the downward spring force is greater than the upward pressure force, resulting in a downward movement of the diaphragm. This increases the flow rate and raises the output pressure.