Effect of Culture Parameters on the Growth of Sparassis crispa Mycelium
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The Effect of Globalization on CulturalIdentityGlobalization has had a profound impact on cultural identity, as it has led to the spread of ideas, values, and practices across the globe. This phenomenon has both positive and negative effects on cultural identity, as it can lead to the preservation and celebration of diverse cultures, but it can also result in the homogenization and loss of traditional practices. In this essay, I will explorethe various perspectives on the effect of globalization on cultural identity, and how it has shaped the way we perceive and interact with different cultures. One perspective on the effect of globalization on cultural identity is that it has led to the preservation and celebration of diverse cultures. As people from different parts of the world come into contact with one another, they have the opportunityto learn about and appreciate the customs, traditions, and beliefs of other cultures. This can lead to a greater sense of understanding and tolerance, as individuals become more accepting of cultural differences. For example, the popularity of international cuisine and the celebration of cultural festivals in different parts of the world demonstrate how globalization has allowed for the sharing and appreciation of diverse cultural practices. On the other hand, globalization has also led to the homogenization and loss of traditional practices within certain cultures. As Western ideals and consumerism spread across the globe, there is a growing concern that traditional customs and values are being eroded. For example, the rise of global fast food chains and the dominance of Western fashion and entertainment have led to the decline of traditional culinarypractices and clothing styles in many parts of the world. This has raised concerns about the loss of cultural diversity and the preservation of unique cultural identities. Another perspective on the effect of globalization on culturalidentity is that it has led to the creation of hybrid cultures. As people from different backgrounds come into contact with one another, they often blend their cultural practices and beliefs to create new and unique cultural expressions. This can be seen in the fusion of music genres, the mixing of culinary traditions, and the adoption of new languages and dialects. For example, the popularity of fusioncuisine and the emergence of new musical styles that blend traditional and contemporary elements demonstrate how globalization has led to the creation of hybrid cultures that reflect the diversity of the modern world. However, the creation of hybrid cultures can also lead to the dilution of traditional practices and the loss of authentic cultural identities. As people adopt elements from different cultures, there is a risk that they may lose touch with their own cultural heritage and traditions. This can lead to a sense of disconnection and alienation, as individuals struggle to reconcile their cultural identity with the influences of globalization. For example, the rise of global consumer culture has led to the spread of Western ideals of beauty and success, which has resulted in the erosion of traditional values and practices in many parts of the world. In conclusion, the effect of globalization on cultural identity is a complex and multifaceted issue that has both positive and negative implications. While it has led to the preservation and celebration of diverse cultures, it has also resulted in the homogenization and loss of traditional practices, as well as the creation of hybrid cultures that reflect the diversity of the modern world. It is important for individuals and societies to navigate the challenges of globalization in a way that preserves and respects cultural diversity, while also embracing the opportunities for cross-cultural exchange and collaboration. By doing so, we can ensure that the impact of globalization on cultural identity is one that promotes understanding, tolerance, and the celebration of the rich tapestry of human culture.。
文化共鸣英文作文高中Culture resonance is a fascinating phenomenon that occurs when people from different cultural backgrounds find common ground and understanding in certain aspects of each other's culture. It's like a magical connection that brings people together, regardless of their differences.When I think about culture resonance, I can't help but recall the time when I attended a traditional Indian wedding. The vibrant colors, the lively music, and the joyful atmosphere were simply infectious. Even though I come from a completely different cultural background, I couldn't help but feel a sense of joy and celebration that transcended any language or cultural barriers.Another experience that comes to mind is when I watched a Japanese tea ceremony for the first time. The meticulous attention to detail, the graceful movements, and the serene ambiance left me in awe. It was a profound experience that made me appreciate the beauty of simplicity and mindfulnessin a way that I had never considered before.One of the most memorable instances of culture resonance for me was when I tried authentic Mexican street food for the first time. The explosion of flavors, the bold spices, and the communal aspect of sharing food with others left a lasting impression on me. It was a moment of pure culinary delight that made me realize the universal joy of good food and good company.I also can't forget the time I attended a traditional African dance performance. The rhythmic beats, the energetic movements, and the sense of community and togetherness were incredibly powerful. It was a reminder of the universal language of music and dance that can bring people together in celebration and unity.Culture resonance is a powerful reminder that, despite our differences, we are all connected by our shared humanity. It's a beautiful thing that reminds us to celebrate diversity, embrace new experiences, and find common ground with others, no matter where they come from.。
人文与科学的关系英语作文_小学万能英语作文2篇关于”人文与科学的关系“的英语作文模板2篇,作文题目:The relationship between Humanities and Science。
以下是关于人文与科学的关系的小学英语模板,每篇作文均为万能模板带翻译。
高分英语作文1:The relationship between Humanities and ScienceHumanistic spirit since I was in primary school, I have done a lot of reading and writing. I like philosophy, politics, science, and fairy tale Taras. I study history carefully, especially about the history of our own people and country.It is always pleasant to sit on the gr and read my books in an open place. For me, my university major will be one of the humanities. In my opinion, when I am with young students in clor anywhere, we will discuss a philosophy of life, a way of thinking, a democratic concept, a concept of right and wrong,and a concept of beauty.中文翻译:人文精神从我上小学开始,我就做了大量的阅读和写作,我喜欢哲学,科学,还有童话般的塔雷斯,我认真地研究历史,尤其是关于我们自己的和国家的历史坐在草地上,在一个空旷的地方读我的书总是令人愉快的。
The Effect of Globalization on CulturalIdentityGlobalization has undeniably had a profound impact on cultural identity around the world. As the world becomes increasingly interconnected through trade, technology, and communication, the boundaries between different cultures are becoming more porous. This has led to a complex and multifaceted relationship between globalization and cultural identity, with both positive and negative implications. One perspective on the effect of globalization on cultural identity is that it has led to the homogenization of cultures. As Western culture, particularly American culture, has spread around the world through media, technology, and consumer products, there is a concern that local traditions and customs are being eroded. This has led to a fear of cultural imperialism, where dominant cultures impose their values and norms on less powerful ones, leading toa loss of cultural diversity. On the other hand, globalization has alsofacilitated the exchange of ideas, values, and traditions between different cultures. This has led to a rich tapestry of hybrid cultures, where elements from different traditions are blended together to create new and vibrant forms of expression. This can be seen in the fusion of different cuisines, the blending of musical styles, and the incorporation of diverse artistic influences into popular culture. In this way, globalization has the potential to enrich and diversify cultural identity, rather than erode it. Another perspective on the impact of globalization on cultural identity is the role of technology and communication in shaping how cultures are perceived and represented. The rise of social media and the internet has made it easier for people to connect with others from different cultural backgrounds, leading to greater awareness and understanding of diverse traditions. This has the potential to break down stereotypes and prejudices, and foster a sense of global citizenship that transcends national boundaries. However, there is also a concern that the spread of Western media and technology has led to a form of cultural hegemony, where the values and norms of dominant cultures are seen as superior to others. This can lead to a loss of cultural authenticity, as people strive to conform to the ideals and standards set by Western societies. Asa result, there is a risk that traditional forms of cultural expression are marginalized or commodified to fit into a globalized market, leading to a loss of cultural integrity. In conclusion, the effect of globalization on cultural identity is a complex and multifaceted issue that has both positive and negative implications. While there is a concern about the homogenization and commodification of cultures, there is also the potential for the enrichment and diversification of cultural identity through the exchange of ideas and traditions. It is important to recognize the value of cultural diversity and to promote a more inclusive and equitable form of globalization that respects and preserves the unique identity of each culture. Only then can we truly harness the potential of globalization to create a more interconnected and harmonious world.。
Process Biochemistry 45(2010)1334–1341Contents lists available at ScienceDirectProcessBiochemistryj 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 /p r o c b ioInfluence of specific growth rate over the secretory expression of recombinant potato carboxypeptidase inhibitor in fed-batch cultures of Escherichia coliJuan-Miguel Puertas a ,∗,Jordi Ruiz a ,Mónica Rodríguez de la Vega b ,Julia Lorenzo b ,Glòria Caminal a ,Glòria González aaUnitat de Biocatàlisi Aplicada associada al IQAC,Departament d’Enginyeria Química,Escola d’Enginyeria,Universitat Autònoma de Barcelona,Edifici Q,08193Bellaterra (Barcelona),Spain bInstitut de Biotecnologia i de Biomedicina,Universitat Autònoma de Barcelona,08193Bellaterra,Spaina r t i c l e i n f o Article history:Received 16February 2010Received in revised form 28April 2010Accepted 30April 2010Keywords:Potato carboxypeptidase inhibitor Fed-batch cultivationSecretory expression in E.colia b s t r a c tA high cell density cultivation protocol was developed for the secretory production of potato carboxypep-tidase inhibitor (PCI)in Escherichia coli .The strain BW25113(pIMAM3)was cultured in fed-batch mode employing minimal media and an exponential feed profile where the specific growth rate was fixed by limitation of the fed carbon source (glycerol).Plasmid loss rates were found to be proportional to the specific growth rate.Distribution of PCI along the cell compartments and the culture media was also dependent on the fixed growth rate.When specific growth rate was kept at =0.10h −1,1.4g PCI L −1were obtained when adding the product present in periplasmic extracts and supernatant fractions,with a 50%of the total expressed protein recovered from the extracellular medium.This constituted a 1.2-fold increase compared to growth at =0.15h −1,and 2.0-fold compared to =0.25h −st,a cell perme-abilization treatment with Triton X-100and glycine was employed to direct most of the product to the culture media,achieving over 81%of extracellular PCI.Overall,our results point out that production yields of secretory proteins in fed-batch cultures of E.coli can be improved by means of process variables,with applications to the production of small disulfide-bridged proteins.Overall,our results point out that control of the specific growth rate is a successful strategy to improve the production yields of secretory expression in fed-batch cultures of E.coli ,with applications to the production of small disulfide-bridged proteins.©2010Elsevier Ltd.All rights reserved.1.IntroductionSecretory expression of heterologous proteins in Escherichia coli has a number of advantages over more common cytosolic expres-sion.First,secretion of the recombinant product is attractive form a downstream processing stand-point,since no cell-disruption steps are needed and contamination with other proteins is reduced both in the periplasm and culture media [1,2].Secondly,the formation of disulfide bridges is actively catalyzed in the periplasmic space [3,4].Also,for proteins that are toxic to the host,secretion may palliate their detrimental effect over culture growth [2].Several proteins have been successfully produced in the periplasmic space and culture supernatants of high cell density cul-tures of E.coli [5,6],but since the capacity of the bacterial secretion machinery is limited and there are several factors that affect protein∗Corresponding author.Tel.:+34935814795;fax:+34935812032.E-mail addresses:juanmiguel.puertas@uab.es ,juanmiguel.puertas@uab.cat(J.-M.Puertas),jordi.ruiz.franco@uab.cat (J.Ruiz),julia.lorenzo@uab.cat (J.Lorenzo),gloria.caminal@uab.cat (G.Caminal),gloria.gonzalez@uab.cat (G.González).expression and translocation [7,8],achieving high protein yields of protein exported through the inner membrane can be a complex task.In this sense,it has been proven that translational and translo-cation levels have to be properly coupled to reach a state where most of the expressed heterologous protein is secreted [9,10].This can be achieved by manipulations of genetic parameters like the promoter strength [11],the nature of the signal sequence [12,13]or the plasmid copy number [14],but optimization of the culture protocols is also necessary.Previous studies show the influence of culture media composition,growth kinetics,induction moment and temperature over secretory protein yields [1,2,5].Potato carboxypeptidase inhibitor (PCI)is a small protein nat-urally occurring in leafs and stems of Solanum tubesorum [15].Composed by 39residues and three disulfide bridges,it has poten-tial biomedical applications given its proven antitumoral properties [16,17].PCI had previously been produced in E.coli using the pIN-III-ompA-derived plasmid pIMAM3,which allows for the translocation of the protein to the periplasmic space where formation of its disulfide bonds was successfully achieved and the active form could be recovered from culture supernatants [18,19].Excretion of PCI out of the cell envelope is probably favored by its small1359-5113/$–see front matter ©2010Elsevier Ltd.All rights reserved.doi:10.1016/j.procbio.2010.04.024J.-M.Puertas et al./Process Biochemistry45(2010)1334–13411335size and compact structure.A fed-batch procedure had previ-ously been designed for the overexpression of PCI in high cell density cultures in semi-complex media,but relatively low lev-els of biomass(15g DCW L−1)were achieved,and the process was not automated,with feedstock additions not responding to any monitored variable.The aim of this work was to design a robust, automated and repeatable fed-batch process at bench-top level in order to increase the production of biologically active PCI by maximizing both the biomass concentrations and the expression-secretion of the inhibitor.Since it was observed that the specific growth rate( )had a major influence in the amounts of excreted PCI,a series of fermentations at differentfixed growth rates were carried out.The dynamics of the PCI concentration profiles in the cytosol,periplasmic space and culture media was analyzed in order to identify and overcome the bottlenecks in the secretory produc-tion of this protein.2.Materials and methodsAll reagents were purchased from Sigma–Aldrich(St.Louis,MO,USA)under otherwise stated.2.1.Strains and plasmidE.coli strain MC1061(hsdR2hsdM+hsdS+araD139 (ara-leu)7697 (lac)X74 galE15galK16rpsL(StrR)mcrA mcrB1)and plasmid pIMAM3were used in previous works[18,19].BW25113( (araD-araB)567, lacZ4787(::rrnB-3),lambda−,rph-1, (rhaD-rhaB)568,hsdR514)was obtained from the Coli Genetics Stock Center at Yale.2.2.Shake-flask cultivation conditionsFor shake-flask experiments,either LB media or MDE media supplemented with100g mL−1ampicillin were used.The composition of LB was,per liter: 10g peptone(Difco),5g yeast extract(Difco)and10g NaCl;whereas the com-position of MDE media was,per liter:5g glucose or glycerol,11.9g K2HPO4,2.4g KH2PO4,1.8g NaCl,3.0g(NH4)2SO4,0.11g MgSO4·7H2O,0.01g FeCl3,0.03g thi-amine and0.72mL of trace elements solution.Trace element solution composition was,per liter:1.44g CaCl2·2H2O,42mg AlCl3·6H2O,50mg ZnSO4·7H2O,160mg of CoCl2·6H2O,1.6g CuSO4,10mg H3BO3,1.42g MnCl2·4H2O,10mg NiCl2·H2O and 20mg of Na2MoO4·H2O.Seed cultures were prepared in50mL culture tubes by inoculating10mL of LB broth with a single colony from a fresh transformation plate,followed by incubation overnight at37◦C and200rpm in an orbital shaker.Shake-flask cultures were typ-ically prepared in500mL shake-flasks using1mL of the seed culture to inoculate 100mL of LB or MDE media,which were then incubated under the same conditions as seed cultures.To induce protein expression,IPTG from a100mM stock was asep-tically added to the desiredfinal concentration.After induction,cells were allowed to grow into stationary phase for7–8h.2.3.Bioreactor cultivation conditionsFed-batch cultivation experiments were carried out using a2L jar and a stan-dard Biostat B®digital control unit.Aflux of1.5vvm of air was injected trough the fermentor to satisfy the respiratory needs of the cultured strain.Additions of15% (w/v)NH4OH were made to keep pH at a set point of7.00.Temperature was set at37◦C.Dissolved oxygen levels were kept at60%of the saturation concentration by means of the stirring speed and/or by mixing the inlet gas with pure oxygen in increasing proportions.Seed cultures of the strain of interest were grown in LB media as described previously for shake-flask experiments.Inocula cultures were prepared in500mL shake-flasks by adding5mL of seed culture into95mL of fresh MDE media,then incubating at37◦C and200rpm in an orbital shaker.Once these cultures reached OD600nm of1–1.2,80mL of them were added into the fermentation jar containing 720mL of MDF media.MDF contains per liter:20.0g glucose,4.5g yeast extract, 2.0g NaCl,4.1g(NH4)2SO4,13.2g K2HPO4,2.6g KH2PO4,0.5g MgSO4,0.03g FeCl3, 25mL of trace elements solution and100mg ampicillin.Once glucose was depleted, the feeding part of the fermentation was started with the addition of FS feeding solution,which contained per liter:450g glycerol,9.6g MgSO4,0.5g FeCl3,0.5g CaCl2·2H2O,0.3g thiamine,32mL trace elements solution and500mg ampicillin. Addition of the feedstock was done according to an open loop method described before in previous works(20).This exponential feeding protocol allows for the con-trol of the specific growth rate of the bacterial culture by limitation of the carbon source(21).No source of phosphate was included in the feedstock in order to avoid the precipitation of Ca3(PO4)2and Fe(PO4);however two punctual additions of a concentrated phosphate solution were done,each equivalent to5g of PO43−.2.4.Biomass and metabolites analysesBacterial growth was followed by optical density measurements at600nm using a spectrophotometer(KONTRON Uvicon941plus Spectrophotometer).Optical den-sity was correlated to dry cell weight through a calibration curve constructed by standard methods[21].Evaluation of plasmid stability was accomplished by plat-ing properly diluted amounts of culture samples on plain LB-agar plates and on then LB-agar plates supplemented with100g mL−1ampicillin.The colony count on plain plates represented the total cells,while the count on the antibiotic contain-ing plates stood for plasmid bearing cells.For the determination of glycerol,glucose, phosphate,ammonium and acetic acid,1mL samples of culture were centrifuged at9000×g for3min in a tabletop centrifuge(Haereus).The supernatant was then filtered through a0.22m syringefilter(Millipore)and purified by HPLC(Hewlett-Packard1050)on an Aminex HPX-87H column(Biorad),with H2SO415mM as the mobile phase at aflow rate of0.60mL min−1.Analysis was done with an IR detec-tor(Hewlett-Packard1047)at room temperature.Phosphates and ammonia were determined using commercial colorimetric kits(Hach Lange).2.5.Cell fractionation and culture supernatant preparationBefore cell fractionation,OD600nm of each culture was determined to determine the broth volume from were2.4mg DCW could be isolated.The sample volume was centrifuged at3000×g,4◦C for10min,and periplasmic extracts were obtained by osmotic shock as described elsewhere[22].The resulting pellet containing spheroplasts was resuspended in300L PBS buffer and sonicated to release sol-uble cytoplasmic proteins using a Vibracell®model VC50(Sonics&Materials).Cell lysates were centrifuged at12,000×g,4◦C for15min to recover the soluble cytosolic contents.Culture supernatants were separated from the bacterial pellet by cen-trifugation at5000×g,4◦C for10min,followed byfiltration with a syringe-driven0.22mfilter device(Millipore).Clear supernatants(40mL)were then loaded ona SepPak C18(1g)Reverse Phase column(Waters),previously equilibrated with acetonitrile and rinsed with ultrapure water.Columns were washed with4mL10% acetonitrile and4mL ultrapure water previous to elution with4mL of30%iso-propanol.When needed,supernatants were concentrated using Amicon or Minicon centrifugalfilter devices(Millipore).2.6.Protein electrophoresis and estimation of protein contentTotal protein in samples content was assessed in triplicate using a commercial kit for the Bradford assay(Biorad)with Bovine Serum Albumin(BSA)as a standard. Separation and visualization of proteins over electrophoresis gels was carried out using12%Bis-Tris gels from the Novex system(Invitrogen)using MES-SDS as run-ning buffer.Upon staining with colloidal Coomassie[23],the bands of interest were quantified by gel densitometry(Kodak Digital Science);this type of quantification was mainly used for the estimation of pre-PCI in the cytosol.2.7.Reverse phase HPLC quantificationReverse phase liquid chromatography was employed to separate and quantify active PCI in periplasmic and supernatant fractions.An Ultimate300HPLC system (Dionex)and a C18cartridge(Waters)were employed,using a sample volume of 100L containing1%TFA.Elution of PCI was done over a gradient of acetonitrile (pH=1.00)from20%to80%.Using standards of purified protein,a calibration curve was constructed to estimate the concentration of active PCI in the injected samples.2.8.Enzymatic assayThe inhibitory activity of PCI samples was determined using a commercial kit (Sigma–Aldrich).This kit allows to measure the activity of carboxypeptidase A(CPA), as well as the screening of inhibitors of this enzyme,as described elsewhere[24]. Non-induced culture samples of BW25113or MC1061(pIMAM3)were used as blanks.3.Results3.1.Shake-flask preliminary experimentsparison of expression between the strains MC1061and BW25113As previously mentioned,the expression system MC1061 (pIMAM3)had successfully been used for the production of PCI in both shake-flask and high-density cultures in complex and semi-complex media[19].However,MC1061is a leucine auxotroph and hence its culture in defined media requires the addition of this amino acid.In small scale cultures this did not constitute a rel-evant inconvenient,but it was found to be a major handicap for high-density cultivation,since the amino acid needs can be several1336J.-M.Puertas et al./Process Biochemistry45(2010)1334–1341Fig.1.Effect of IPTG concentration on extracellular PCI yields in shake-flask cultures of BW25113(pIMAM3).folds higher and moreover leucine exhibits a low solubility in aque-ous media.Addition of other amino acids source commonly used in culture media(such as hydrolyzed casein extracts,peptone or yeast extract)is incompatible with the fed-batch cultivation pro-tocol used in our research group which is carried out in minimal medium for several reasons:lower cost,higher repeatability of the results,and possibility of controlling the specific growth rate by limitation of the availability of a single carbon source.To overcome this problem,pIMAM3was transformed into the prototrophic strain BW25113.We then compared the expression of PCI using both strains in three different culture media:LB,defined medium with glycerol as the carbon source(MDE,glycerol),and defined medium with glucose as carbon source(MDE,glucose). After5h of induction,culture supernatants were purified and ana-lyzed.Final yields of extracellular PCI were determined and are presented in Table1.Overall,BW25113exhibits a more desirable behavior for the expression of PCI.It can also be observed that higher concentra-tions of extracellular product were obtained in MDE when glycerol was employed as the carbon source.Increased secretion in defined media compared to complex media has already been described elsewhere[7].3.1.2.Effect of inducer concentration over cell growth andglycerol consumptionConcentration of inducer is known to be another important variable in the production of recombinant proteins[25–27].A series of experiments was conducted to study the expression of PCI in BW25113(pIMAM3)under different concentrations of IPTG. Results are depicted in Fig.1,which shows that concentrations over 250M IPTG do not increase notably the PCI yield.Also,the effect of the induction over cell metabolism was studied by conducting parallel growth experiments with and without addition of IPTG. Induction of PCI expression resulted in a decrease of the specific growth rate andfinal biomass value,with a growth arrest hap-pening after approximately two duplications post-induction.It was also determined that the glycerol/biomass yield during the induc-tion phase was around20%higher than that of the non-induced growth(S/X=2.8g glycerol g−1DCW versus S/X=3.4g glycerol g−1 DCW).These parameters are necessary for the control of the growth rate in the following fed-batch cultures according to the protocol described in Section2.3.2.Bioreactor experiments3.2.1.Development of a fed-batch protocol for the high celldensity cultivation of BW25113(pIMAM3)In previous studies of our research group a minimal balanced media was designed and successfully used for the growth of E. coli to high cell densities.An exponential feed profile was used to control the specific growth rate by limitation of the carbon source while maintaining appropriate levels of other main nutri-ents like nitrogen and phosphorous[20,21,25].Thus,thefirst step to scale up the production of PCI from shake-flask to bioreactor scale was carrying out a non-induced fed-batch culture of BW25113 (pIMAM3)according to this protocol,in order to validate its effi-cacy for this particular expression system.It is well known that control of growth rates is crucial to avoid accumulation of undesir-able metabolites,mainly acetic acid[28,29],and also has a proven impact on the production yield of recombinant proteins[30].Glucose was chosen for the discontinuous stage of the fermen-tation because of its reduced cost and faster growth kinetics of the strain over this substrate.This phase of the fermentation lasted around13.5h,when glucose was depleted,which was evidenced by a sudden rise of the dissolved oxygen concentration and also an increase of the pH to the maximum tolerated by the control loop (pH=7.05).The biomass achieved at this point was6.6g DCW L−1 (OD600nm=21).The feeding was then started,programming the parameters of the control software to maintain a specific growth rate of =0.25h−1.Glycerol,instead of glucose,was employed in the feedstock for the fed-batch since growth over thefirst substrate yielded higher amounts of extracellular PCI in shake-flask cultures (see Table1);and it is in the fed-batch stage where induction takes place.Fig.2depicts the evolution of biomass,glucose,glycerol,ammo-nium,phosphate,acetic acid and dissolved oxygen along the fermentation.Levels of this last metabolite were maximal at the end of the batch stage(1.25g L−1),but were always under critical levels.Concentrations of ammonium and phosphate followed the expected trend throughout the process,never reaching inhibitory or limiting values.The fed-batch stage ended after8.5h,when it was not possible to keep the dissolved oxygen concentration over10%of saturation even supplying1.5vvm of pure oxygen. The point of oxygen exhaustion will be considered as the end-point for all the fed-batch cultures.Afinal biomass concentration of58.2g DCW L−1(OD600nm≈180)was reached.Plasmid stability under these conditions was satisfactory,with over90%of the cells exhibiting ampicillin resistance at the end of the process.3.2.2.Production of PCI in fed-batch culturesOnce the efficacy of the fed-batch protocol for the high cell den-sity cultivation of BW25113(pIMAM3)was tested and the growth limit was determined,a series of induced cultures were performedTable1Specific growth rates and extracellular PCI yields obtained in shake-flask cultivation of BW25113(pIMAM3)and MC1061(pIMAM3)in LB and defined media.Strain LB MDE-glycerol MDE-glucosemax(h−1)P/X(mg PCI g−1DCW) max(h−1)P/X(mg PCI g−1DCW) max(h−1)P/X(mg PCI g−1DCW)BW251130.64±0.05 2.4±0.070.41±0.03 2.9±0.050.53±0.06 1.6±0.08MC10610.62±0.06 1.7±0.040.48±0.05 2.0±0.060.52±0.04 1.4±0.05J.-M.Puertas et al./Process Biochemistry45(2010)1334–13411337Fig.2.Time-course of fed-batch culture of BW25113(pIMAM3)without induction.Non-induced culture atfixed specific growth rate of =0.25h−1.Concentrations of biomass concentration( ),glucose( ),glycerol( ),ammonium(♦),phosphate( ),acetate( )and dissolved oxygen(᭹)concentrations are shown.A continuous vertical line is used to distinguish the batch and fed-batch stages.Punctual additions of phosphate are depicted with an arrow.in which the only variable parameter was the specific growth rate fixed by the feed profile.The choice of the induction moment was done based on the number of duplications post-induction observed on shake-flask cultures as a rough estimate of the effect of PCI expression over cell growth.Bearing in mind a previous induc-tion strategy for the expression of a recombinant aldolase under the control of a mild promoter[21],it was reasoned that an early induction might have prevented the system from reaching the max-imum biomass determined in the non-induced culture,and a late induction would have shortened the induction time,limiting pro-tein expression.Following this rationale,it was chosen to induce at a biomass concentration of around15g DCW L−1(OD600nm=45)so that after two duplications afinal biomass of nearly60g DCW L−1 could still be reached,as for the case of the non-induced culture. Fig.3A–C presents the results of these fermentations in terms of cell concentration,specific growth rate and active PCI concentration in the culture media.It can be observed that growth patterns in all three fermenta-tions followed the expected kinetics(i.e.the specific growth rate was kept at thefixed value with an average7%deviation from the set point);reaching a maximum biomass very similar to that of the non-induced culture.Also,concentrations of carbon source, ammonium,phosphate and acetic acid were kept on the desired levels(data not shown).Particularly,the concentration of glyc-erol remained close to zero during the fed-batch phase of all three processes,validating the strategy of growth control by substrate limitation.However,the amount of extracellular recombinant product depended highly on thefixed growth rate,i.e.growth at =0.1h−1 resulted in2.3-and12.1-fold increases in the concentration of extracellular PCI,respect to the fermentations carried out at =0.15h−1and =0.25h−1,respectively.In order to investigate the causes of these observations,we compared plasmid stability profiles and distribution of protein along the different cellular com-partments for the three cases.3.2.3.Effect of thefixed specific growth rate on plasmid loss ratesFig.4presents the plots of plasmid stability over the induction phase of the fermentations,and also that of the non-induced cul-ture.It can be seen that plasmid loss rates are proportional to the fixed growth rate.It is known that in high cell density cultures ampicillin can be readily degraded,with the consequent loss of selective pressure[31,32].This would promote an increased ten-dency for the cells to lose pIMAM3.Dependence of plasmid loss rates with growth rates has already been reported in several studies [33–35].It is important to recall that the end of the fermentations is imposed by the oxygen-transfer limitation,and in the case of the growth at =0.25h−1this boundary is reached earlier,and with a smaller proportion of PCI-productive biomass,resulting in a decrease in both the induction time and the process productivity.3.2.4.Effect of thefixed specific growth rate on protein expression,secretion and excretionAs it previously shown,levels of excreted PCI varied signifi-cantly with the growth rate at which production was carried out. In order to study this correlation,the intracellular contents of PCI were assessed;both as presecretory or immature protein in the cytosol and in active form in the periplasm.Fig.5presents thefinal localization of PCI in the cytosolic extracts,periplasmic extracts and culture supernatants for the production fermentations.Sur-prisingly,a significant amount of the recombinant product was found in the periplasmic space,a fact that contrasts with previous studies where the protein was exclusively found in the extracellu-lar milieu[19].Secretion of PCI to the periplasmic space and culture media represents a76%of the total protein at =0.25h−1,87%of the total protein at =0.15h−1and96%at =0.10h−1,as illus-trated in Fig.6.Regarding the proportion of excreted PCI,even more striking differences were found:extracellular PCI constituted6.9% of the total protein at =0.25h−1,32.2%at =0.15h−1and50.0% at =0.10h−1.In order to point out the effect of the specific growth rate over the distribution of the recombinant product,Fig.7shows the time evo-lution of the PCI amount(mg)in the different cell compartments.It must be noted that for a given time point of the fermentation,the quantities of pre-PCI in the cytosol and PCI in the periplasm depend on the total biomass at that instant,since these concentrations are cell-bound(in contrast to the concentrations of extracellular PCI). To be able to compare the total PCI produced in each compartment, we calculated the quantity of pre-PCI in the cytosol and PCI in the periplasm using the concentrations in the corresponding extracts and the protocol described in Section2(i.e.knowing that300L of cytosolic and periplasmic extracts are prepared from2.4mg DCW).1338J.-M.Puertas et al./Process Biochemistry 45(2010)1334–1341Fig.3.Time-course of induced fed-batch cultures of BW25113(pIMAM3)at dif-ferent fixed specific growth rates.(A) =0.25h −1,(B) =0.15h −1,(C) =0.10h −1.Biomass (᭹)and PCI ( )concentrations in culture supernatants are shown.A solid vertical line is used to distinguish the batch and fed-batch stages;whereas the induction moment is depicted with a dashed vertical line.Regarding extracellular PCI,it was considered that the effective vol-ume of clear supernatant after centrifugation is different than that of the culture broth,since biomass occupies a significant space,especially at high cell densities.In this sense,a calibration curve correlating recoverable media volume and cell concentration was constructed (data not shown).Also,for further calculations involv-ing biomass concentrations,only the plasmid bearing cells wereconsidered.Fig.4.Plasmid loss profiles for the fed-batch cultures of BW25113(pIMAM3). =0.25h −1( ), =0.15h −1(♦)and =0.10h −1( );non-induced culture at fixed specific growth rate of =0.25h −1(᭹).Note :For the last case ,the data corresponds to the number of duplications as if it had been induced at the same biomass concentration than the induced experiments .A quick-glance comparison of the protein distributions shows how levels of pre-PCI accumulation in the cytoplasm are pro-portional to the specific growth velocity,i.e.proportions of inactive presecretory protein are highest at =0.25h −1.Also,for =0.25h −1,levels of protein in the periplasm increase up to end of the process,whereas for =0.15h −1and =0.10h −1,there is a decline in the PCI content of the periplasmic space 7.5and 12h post-induction,respectively,as a consequence of enhanced excretion of the protein out of the cell.This effect had already been reported for the high-level expression of cholera toxinB in the periplasm of E.coli [36].All these observations seem to point out that the disparity in the amounts of secreted PCI are related to the relative rates at which the protein is produced in the cytosol,secreted to the periplasmic space,and excreted to the culturemedia.Fig.5.Analysis of final cell fractions.Soluble cytoplasmic fractions (ec),periplas-micfractions (ep)and supernatants (sn)were separated by SDS-PAGE and stained by Colloidal Coomassie blue.(Lanes 3–5)fractions corresponding to =0.25h −1;(lanes 7–9)fractions corresponding to =0.15h −1;lanes 11–13,fractions corresponding to =0.10h −1and (lanes 1and 15)molecular weight marker.Notice the molecular weight difference between the pre-secretory and mature PCI in the ec and ep -sn samples,respectively.。
增加对文化的见解英文作文1. Culture is a reflection of a society's values, beliefs, and traditions. It is a way for people to express their identity and connect with others who share similar values. From music and art to language and cuisine, culture is a diverse and complex aspect of human life.2. One of the most interesting things about culture is how it evolves over time. As societies change and new ideas emerge, cultural practices and traditions may adapt or disappear altogether. For example, the rise of technology has had a significant impact on the way we communicate and interact with each other, which in turn has influenced the development of new forms of art and music.3. Another important aspect of culture is its role in shaping our perceptions of the world around us. Different cultures may view the same event or object in vastly different ways, depending on their values and beliefs. This can lead to misunderstandings and conflicts, but it canalso foster greater understanding and appreciation of diverse perspectives.4. Culture also plays a key role in the way we express ourselves. Whether through language, dance, or visual art, cultural forms of expression allow us to convey complex emotions and ideas in ways that are unique to ourparticular society. This can create a sense of unity and belonging among members of a culture, while also allowing for individual expression and creativity.5. Finally, culture is an important part of our collective history and heritage. By preserving and celebrating cultural traditions, we can honor the achievements and struggles of our ancestors, while also passing on valuable knowledge and skills to future generations. This helps to create a sense of continuity and connection across time, even as our societies continue to evolve and change.。
关爱地球母亲英语作文60字六年级当地球上没有了树木,当森林里没有了小鸟;当地球上没有了河流,当小河里没有了鱼虾。
我不知道生活会变成什么样子。
警钟已经敲响,让我们携起手来,关爱地球,关爱你我。
让我们一起来看看吧!今日在这里共享了关爱地球母亲英语作文60字六年级,盼望能帮到你。
关爱地球母亲英语作文60字六年级1Now, fewer nd fewer resources on erth, now the environment is becoming worse. In order to mke the sustinble development of humn civiliztion, low-crbon life strted. This yer, the world expo held in Shnghi, Chin, the theme is: city, better life! , the purpose is to promote low-crbon life.In the city, t the countless chimneys in the smoke, thousnds of drin in the dischrge of sewge, leding to the greenhouse effect, cid rin nd other dissters, cused huge impct on the environment. rths pvilion is four-storey building, min solr wter curtin wll is one of the biggest bright spot. The technology wll prototype is French lsce he middle school wll of the sun, in the locl pplied in heting in winter.Considering the Shnghi summer high temperture ndwet, rths the solr wll in front of the pvilion nd dd the function of the summer. Solr wter curtin wll from outside to inside, including three lyers, the outer lyer is composed of solr pnels nd thick glss, the middle lyer is cn open closed ir lyer, the inner lyer is the wter fter the wter curtin of glss lyer. Prt in the summer, solr pnels cn block off the sun, outdoor hot ir into the ir lyer, contct the wter curtin wll, the effect of cooling nd cooling by trnspirtion.Shnghi is too hot in summer, wter curtin wll cnt completely replce the ir conditioning. Generl representtive MryseDondrille ldy sid, but the wter curtin wll cn mximize reduce indoor temperture, reducing dependence on centrl ir conditioning the entire rchitecture. Support the low crbon life, protect erths environment关爱地球母亲英语作文60字六年级2参考译文】:人们常常说地球就像我们的母亲。
The effect of culture on economyCanada is famous for its immigrant culture. So it is an open country as well as welcomesforeign investment in economy, contributing to be a large trading nation.Because Canadian culture is influenced deeply by American and French culture, its trade is mainly centered by Americas and France.Canadian culture is a term that embodies the artistic, culinary, literary, humour, musical, political and social elements that are representative of Canada and Canadians. Throughout Canada's history, its culture has been influenced by European culture and traditions, especially British and French, and by its own indigenous cultures. Over time, elements of the cultures of Canada's immigrant populations have become incorporated into mainstream Canadian culture.Canada is often characterized as being "very progressive, diverse, and multicultural". Canada's culture draws influences from its broad range of constituent nationalities, and policies that promote a just society are constitutionally protected. Canadian Government policies—such as publicly funded health care; higher and more progressive taxation; outlawing capital punishment; strong efforts to eliminate poverty; an emphasis on cultural diversity; strict gun control; and most recently, legalizing same-sex marriage—are social indicators of Canada's political and cultural values.In general, Canadian nationalists are highly concerned about the protection of Canadian sovereignty and loyalty to the Canadian State, placing them in the civic nationalist category. It has likewise often been suggested that anti-Americanism plays a prominent role in Canadian nationalist ideologies. Cultural protectionism in Canada has, since the mid-20th century, taken the form of conscious, interventionist attempts on the part of various Canadian governments to promote Canadian cultural production.As far as its arts,aboriginal artists were producing art in the territory that is now called Canada for thousands of years prior to the arrival of European settler colonists and the eventual establishment of Canada as a nation state. The works of most early Canadian painters followed European trends. However, Since the 1930s, Canadian painters have developed a wide range of highly individual styles. Emily Carr became famous for her paintings of totem poles in British Columbia.And Canadian literature is often divided into French- and English-language literatures, which are rooted in the literary traditions of France and Britain, respectively. Canada’s early literature, whether written in English or French, often reflects the Canadian perspective on nature, frontier life, and Canada’s position in the world, for example the poetry of Bliss Carman or the memoirs of Susanna Moodie and Catherine Parr Traill. These themes, and Canada's literary history, inform the writing of successive generations of Canadian authors, from Leonard Cohen to Margaret Atwood. By the mid-20th century, Canadian writers were exploring national themes for Canadian readers.Then Canadian authors have accumulated numerous international awards. In 1992, Michael Ondaatje became the first Canadian to win the Man Booker Prize for The English Patient.A number of Canadian pioneers in early Hollywood significantly contributed to the creation of the motion picture industry in the early days of the 20th century.] Over the years, many Canadians have made enormous contributions to the American entertainment industry, although they are frequently not recognized as Canadians.。
International Journal of Science Culture and SportDecember 2013; 1(4)ISSN : 2148-1148Doi : 10.14486/IJSCS39Copyright©IntJSCS ( ) - 22The Effect of Cultural Background Knowledge on Learning EnglishLanguageDr. Ibrahim, M. SabatinMinistry of Education / PALESTINEE-mail: sabateenibrahim2002@ - Mobile: 009720599388439AbstractThis study aims to investigate the effect of cultural background knowledge on learning English Language. It also aims to investigate if there are significant differences between subjects' performance in reading comprehension according to sex and general ability in English (GAE). The study aims at answering the following questions: 1. To what extent is the effect of cultural background knowledge on subjects' performance in reading comprehension? 2. What is the difference in performance in reading comprehension between male and female subjects who have cultural background knowledge and those who do not have any knowledge? 3. What is the difference between subjects' performance in reading comprehension texts which are loaded with American culture and their general ability in English. ?The population of this study consisted of all first-year students majoring in English at Hebron University in the first semester of the academic year 2011/2012. They were 600. The sample of the study consisted of 60 subjects, males and females divided into four groups, two experimental and two controlled. The researcher followed the experimental method. Means, standard deviations and Pearson Product Moment Correlation were calculated by using SPSS program. The study revealed the following results: 1. There are statistically significant differences in performance in reading comprehension between subjects who have cultural background knowledge and those who do not have any knowledge. 2. There are no statistically significant differences in performance in reading comprehension between male and female subjects who have cultural background knowledge and those who do not have any knowledge. 3. Subjects' GAE revealed that there are significant differences in performance in reading comprehension between subjects who have cultural background knowledge and those who do not have any knowledge.In the light of the results of the study, the researcher recommends the following: Teachers should activate two types of prior knowledge when introducing new information: subject knowledge and cultural knowledge.Key words: Cultural Knowledge, Teaching, Reading ComprehensionM. Sabatin IBRAHIM, The Effect of Cultural Background… 1(4): 22-32 1. IntroductionOver the last decade there has been an explosion of interest in learning English in the Arab World. Bernhardt (1993) lists three reasons for the interest in second language acquisition as it relates to literacy skill. The first reason is concerned with social- political interests. Some learners require instructions in the native language for success in school. Other non-native adult learners need employment for survival and therefore must attain functional literary skills. A second reason for the general interest in literacy skills in second language is pedagogical. Reading ability is acknowledged to be the most stable and durable of the second language modalities. That means, learners may lose their productive skills but still be able to comprehend texts with some degree of proficiency. The third reason for this interest is cognitive.Bright and Macgregor (1970) note that where there is little reading there will be little language learning. Nuttall (1996) adds that reading is a highly effective means of extending the command of language. Gibson and Levin (1975) also state that reading has received more attention than other aspects of education, so there is small wonder that instruction in the early grades is organized around learning to read because almost everyone expresses concern about students learning to read. (Destefano, 1978:232-235). Knowledge of reading in a foreign language, in particular English is so necessary nowadays for most learners. Too much of the professional, technical and scientific information is published in English, so the ability to read in English is required by many people.1.2 Significance of the StudyIn Palestinian schools reading comprehension constitutes a major part of the English language curriculum in all grades. In most cases, the textbooks accompanied by sets of exercises and activities that revolve around the reading passage. In other words, there are vocabulary exercises and exercises on syntax derived from and based on the reading passage. In the General Secondary School Certificate Examination, the reading grade constitutes 20% to 30% of the total grade in the English Examination. However, a considerable number of students fail to comprehend the reading passages and many of the teachers of English are often discouraged by the low grades the students obtain in reading comprehension tests at colleges and universities. So the researcher intends to investigate the factors that affect reading comprehension. In the present study the researcher investigated the effect of cultural background knowledge. The lack of sufficient research on the precise contribution of linguistic knowledge to reading comprehension combined with the serious limits of the few existing studies emphasized the need for a study that can accomplish the following:1. explore the learner's knowledge of culture so as to determine its contribution as well as the precise contribution of each to reading comprehension. (Mecartty, 1994; Dwaik, 1997)2. break with the traditional perspective of measuring learner's knowledge of the linguistic features of the language contained in the text and therefore, investigate the learners knowledge independent of text comprehension (Mecartty, 1994; Dweik, 1997) Furthermore, the results of answering the questions of the study are expected to achieve the following results:International Journal of Science Culture and Sport (Int JSCS)Dec 2013 1. This study is expected to help English teachers by drawing their attention to the main factors that affect students’ achievement in reading comprehension.2. It is expected to help students to improve their level in reading comprehension.3. It is expected to help the English language curriculum designers and draw their attention to the types of texts to be included in textbooks.In summary, the researcher hopes that this study may contribute to improving students' level in reading comprehension by drawing teachers' attention to place more emphasis on vocabulary, grammar and cultural background knowledge when dealing with reading comprehension texts.1.3. Statement of the ProblemThe study of foreign language comprehension is a complex phenomenon compounded by the fact that many types of processes and factors need to be accounted for and explained. The knowledge that the reader brings to the process is one of those many factors. “I t is generally known that good knowledge of vocabulary and grammar helps the reader to understand the material he reads” (Faraj, 1998: 53). Reading is probably the most common of the four skills to be improved, and it may seem to be the easiest of the skills to test. However, testing reading does have difficulties, and there are issues that anyone testing reading should be aware of the fact that traditional reading tests tend to make use of short prose passages and ask general comprehension questions. These often do not deal with the variety of skills involved in reading or the variety of texts that testees may encounter.According to the researcher's experiences as a teacher of English he noticed that most of the students finish high school and join the university without having the ability to read and to answer reading comprehension questions on reading passages. So we have to investigate the factors that affect reading skill in order to improve it. Kilani (2001) claims that a learner is expected to read with less comprehension if he or she does not possess adequate cultural background knowledge. Moreover, Tseng (2002) points out that successful language learning requires knowing the culture that underlies language.Unfortunately, many classrooms today lack the use of "real language", and a general look at PETRA and OXFORD English Course textbooks used in Palestine indicate that the reading comprehension texts included are not authentic, but rather prepared for specific pedagogical purposes (Yousef, 1998). Consequently, EFL learners do not have the opportunity to get through the target language components explicity that is necessary for successful communication.1.4. Purpose of the StudyThe purpose of the present study is to investigate the effect of cultural background knowledge on the learners' achievement in reading comprehension. In short we can say that this study will try to help teachers of English in Palestine to improve their students’ level in reading comprehension to achieve good communication in foreign language.M. Sabatin IBRAHIM, The Effect of Cultural Background… 1(4): 22-32 1.5. Research QuestionsThis study will attempt to answer the following questions1. To what extent is the effect of cultural background knowledge on subjects' performance in reading comprehension?2. What is the difference in performance in reading comprehension between male and female subjects who have background knowledge on 5 American culture and those who do not have any knowledge?3. What is the difference between subjects' performance in reading comprehension texts which are loaded with American culture and their GAE?1.6. HypothesesIn order to answer the questions of this study, these questions were converted into the following null hypotheses:1- There is no significant difference in performance in reading comprehension between subjects who have cultural background knowledge and those who do not have any knowledge.2- There is no significant difference in performance in reading comprehension between male and female subjects who have cultural background knowledge and those who do not have any knowledge.3- There is no significant difference between subjects' performance in reading comprehension texts which are loaded with American culture and their GAE.1.7. Limits of the StudyThe researcher acknowledges the following limitations to the study. This study will be limited to the first- year English students at Hebron University for the academic year 2008/2009. Only one test type was used to measure the subjects' ability in reading comprehension, i.e. (Multiple-choice test) . The results of this study could not be generalized out the boarders of these limits. All of the subjects are non-native speakers of English. The results of this study could be generalized only to other similar conditions.2. MethodologyIn order to achieve the purpose of the study the researcher conducted an experimental study. The sample of the study consisted of 120 male and female students divided into four homogenous groups: two experimental and two controlled groups. Two post tests will be given to the four groups.International Journal of Science Culture and Sport (Int JSCS)Dec 2013 2.1. Population and SampleThe population of this study consisted of all first -year students majoring in English at Hebron University in the first semester of the academic year 2008/2009. They were 600. The sample of the study consisted of 60 subjects, males and females divided into four groups, two experimental and two controll. The researcher followed the experimental method.The researcher gave the first experimental group five lectures on lexis and syntax while the first controlled group was not given any lecture. He also gave the second experimental group five lectures on American culture while the second controlled group was not given any lecture. The researcher gave the four groups of subjects a post test. The first experimental and controlled groups were given a post test concerns lexical and syntactic knowledge while the second experimental and controlled groups were given a post test concerns target language culture. The post test consisted of two texts followed by twenty questions for each group. Means, standard deviations and Pearson Product Moment Correlation were calculated by using SPSS program.3. ResultsThe study revealed the following results:3.1. The Effect of Cultural Background Knowledge on Reading ComprehensionThis section will discuss the results of the effect of cultural background knowledge on reading comprehension.Hypothesis 11-There is no significant difference in performance in reading comprehension between subjects who have cultural background knowledge and those who do not have any knowledge.Table 1. Means and Standard Deviation of Students' Performance in Reading ComprehensionComparing the mean scores of both texts we notice that the experimental group which was given five lectures about American culture assigned higher mean scores ( M= 0.717, Sd=0.116) than the controlled group which was not given any (M=0.538,Sd=0.156 ). WeM. Sabatin IBRAHIM, The Effect of Cultural Background… 1(4): 22-32 notice from Table 4-12 that the hypothesis is rejected. This result does not support the fourth hypothesis which says 'that there is no significant difference between cultural background knowledge and student's performance on reading comprehension'.A significant difference in performance in reading comprehension was found between subjects who have cultural background knowledge and those who do not have any knowledge. (P<0.05). These results agree with the results of Razi's study (2003) which indicated that cultural schema appears to have a significant affect on the comprehension of short stories.Razi investigated the effect of cultural background knowledge and reading activities on reading comprehension. He carried out his study at Canakkale Onsekiz Mart University. His sample consisted of 60 participants. He drew his subjects from 3rd year students at the department of ELT at Canakkale University and divided them into two groups. The results showed that cultural schema appears to have a significant effect on the comprehension of short stories. The treatment group received the modified version of the story while the other group received the original story. After that he gave both groups a post test. According to the findings of the present study culture familiarly has a great effect on reading comprehension, and this support the findings of previous studies which indicated that the lack of cultural knowledge affects on reading comprehension. The reviewed studies indicated that there is a significant difference between students who have cultural background knowledge and their performance on reading comprehension. Also, the results support Sultans' results which indicated that there is a significant difference at P<.05 between culture familiarity and reading comprehension. And this supports similar findings in the literature, which have suggested that cultural background knowledge facilitates comprehension, being an integral aspect of reading comprehension. (Sultan, 2004)In summary, it could be said that cultural background knowledge plays an important positive role in students' achievement in reading comprehension. Moreover, good knowledge of other cultures helps students a lot in dealing with reading comprehension texts.Hypothesis 2There is no significant difference in performance in reading comprehension between male and female subjects who have cultural background knowledge and those who do not have any knowledge.Table2. Means and Standard Deviation of Students' Performance on Reading ComprehensionInternational Journal of Science Culture and Sport (Int JSCS)Dec 2013 This result supports the second hypothesis which says ' there is no significant difference in performance in reading comprehension between male and female students who have cultural background knowledge and those who do not have any knowledge. The results showed that there is no significant difference in performance in reading comprehension at P <0.05 between male and female students who have cultural background knowledge and those who do not have any knowledge. This result disagrees with the result of Sultan's study (2001) which indicated that there is a significant difference at P <0.05 between males and females performance in reading comprehension with texts which are loaded with cultures.According to the researcher, this could be attributed to the fact that1- males and females live under the same severe economical conditions.2- males and females are strongly affected by the political situation in Palestine.3- males and females finished the General Secondary Certificate Exam and entered Hebron University at the same time.In summary, it could be said that cultural background knowledge does not play an important role in reading comprehension according to sex. The results of the present study showed that there is no significant difference at P <0.05 between male and female students who have cultural background knowledge and their performance in reading comprehension. Hypothesis 3There is no significant difference between subjects' performance in reading comprehension texts which are loaded with American culture and their GAE.Table 3. Results of the Two Way ANOVA of the Subjects' performance in ReadingGAE: general ability in EnglishThe results showed that there is a significant difference in performance in reading comprehension at P<0.05 between students' who have cultural background knowledge and those who do not have any knowledge and their general ability in English. This result may beM. Sabatin IBRAHIM, The Effect of Cultural Background… 1(4): 22-32 attributed to the students' achievement motivation. A student who gets high marks will have strong motivation which derives him to achieve more, whereas a student who gets low marks will have a low motivation to study more.Table 4. Means and Standard Deviation of the Subjects' Performance in Reading Comprehension Texts Which are Loaded with Cultural Background Knowledge According toGAE: general ability in EnglishThe results showed that there is a significant difference between the performance of students in reading comprehension and their general ability in English. This result is in agreement with the findings of the previous studies which indicated that there is a significant difference between students' GAE and their performance in reading comprehension. And this is a fact that students whose GAE is high, will assign high scores in reading comprehension and those who have low GAE will assign lower scores. These results agree with the findings of Sultan which indicated that there is a significant difference between the performance of students in reading comprehension and their GAE. Indicating that background knowledge has an influence on EFL learners reading comprehension is congruent with the results of (Carrell, 1924; Lee,1986; Horiba, 1990; Ziddan, 1994; Sultan, 2004). On the other hand, this result appears to go against the findings of Johnson (1981) and Floyd and Carrell (1987) who found that background knowledge had more effect on test scores than did the level of language proficiency.In summary, it could be said that cultural background knowledge plays an important role on reading comprehension according to GAE.International Journal of Science Culture and Sport (Int JSCS)Dec 2013 1- There are statistically significant differences in performance in reading comprehension between subjects who have cultural background knowledge and those who do not have any knowledge.2- There are no statistically significant differences in performance in reading comprehension between male and female subjects who have cultural background knowledge and those who do not have any knowledge.3- Subjects' GAE revealed that there are significant differences in performance in reading comprehension between subjects who have cultural background knowledge and those who do not have any knowledge.The results of the study revealed that the null hypotheses have been rejected; however, the hypotheses which concern the effect of lexical, grammatical and cultural background knowledge on students' performance in reading comprehension according to sex have been confirmed.In the light of the results of the study, the researcher recommends the following:1- Teachers of English language should give more attention to lexical and lacitammarg knowledge as the two main factors in improving reading comprehension.2- Teachers should activate two types of prior knowledge when introducin new information: subject knowledge and cultural knowledge.3- Developing learners' understanding of the target language culture so as to promote international cooperation, and to gain access to life and thought of people who speak the target language.4. ConclusionsTo conclude, it could be said that reading comprehension plays an important role in teaching English language. Lexical, grammatical and cultural background knowledge affects reading comprehension so teachers of English should emphasize these three factors. This implies that they should have sufficient preparation in vocabulary, syntax and cultural background knowledge. Also, it implies that students who lack knowledge of vocabulary, syntax and cultural background tend to have difficulty with reading comprehension. The results of the present study revealed the following:1. There is a statistically significant difference in performance in reading comprehension between subjects who have cultural background knowledge and those who do not have any knowledge.2- There is no statistically significant difference in performance in reading comprehension between male and female subjects who have cultural background knowledge and those who do not have any knowledge.M. Sabatin IBRAHIM, The Effect of Cultural Background… 1(4): 22-32 3. There is a statistically significant difference between subjects' performance in reading comprehension texts which are loaded with American culture and their GAE.4. Cultural orientation of the text has a significant effect on reading comprehension. Readers are expected to attain the writers intended meaning by combining existing information with what they read. (Nuttal, 1996).5. RecommendationsIn the light of the results of the research, the researcher recommended the following:1- Teachers should activate two types of prior knowledge when introducing new information: subject knowledge and culture knowledge. The first is the students’ previous knowledge of the subject. World knowledge is what students have learnt through their interactions with the world. Both are supposed to be crucial to facilitate reading comprehension.2- Activating learners’ schemata, especially when introducing new material that is culturally unfamiliar.3- Developing learners’ cultural understanding of the target language culture to promote international cooperation and to gain access to life and thought of people who speak the target language.International Journal of Science Culture and Sport (Int JSCS ) Dec 2013Copyright©IntJSCS ( ) - 32REFERENCESAlderson JC (1984). Reading in a Foreign Language: a Reading Problem or a language problem? .Reading in a Foreign Language. 7: 465-503.Alptekin C (1993). Target Language Culture in EFL Material. ELT Journal, 47, 2, 136-142. Anderson RC and Pearson D (1984). A Schema-Theoretic view Reading Research. New York: Longman.Ausubel D (1963). The Psychology of Meaningful Verbal Learning. New York: Grune. Badrawi N (1994). Culture, Reading and Foreign Language Learner: The Effect of Culture on Reading Comprehension. CDELT. Ain Shams University.Barlett FC (1932). Remembering: A study in Experimental and Social Psychology. Cambridge: Cambridge University Press.Carrell P and Floyed P (1987). Effects on ESL Reading of Teaching Cultural Content Schemata. Language Learning, 37. 1, 89-106.Dwaik R (1997). The Role of Syntactic Knowledge in English as a Foreign Language Reading Comprehension. The Ohio State University.Faraj S (1998). Perceived Causes for the Weakness of Ninth Grade Students in English Listening Skill at West Bank UNRWA Schools. M.A. Thesis, Al-Quds University, Jerusalem. Mecartty F (1994). Lexical and Grammatical knowledge in second language reading and listening comprehension, UM Dissertation Services.Razi S (2003) The Effect of Cultural Schema and Reading Activities on Reading Comprehension. M.A. Thesis. Canakkale Onsekiz Mart University. Turkey.。
文化因素对英语教学的影响The Influence of Culture Factors in English TeachingContents Abstract (1)Key words (1)I. Introduction (2)II. The Relationship between Language and Culture (2)1. Different definitions of culture (2)2. The relationship between language and culture (3)III. The Purpose of Culture Teaching (4)1. The purpose of culture teaching (4)2. The content of culture teaching (4)IV. The Problem and Solving of Culture Teaching (6)1. Listening (7)2. Vocabulary (8)3. Reading (8)4. Writing (9)5. Translation (9)V. The Objective of Culture Teaching (10)VI. The Strategies of Culture Teaching (10)VII. Conclusion (12)References (12)Influence of Culture Factors in English TeachingAbstract: Language is the keystone of culture. Without language, culture would not be possible. On the other hand, language is influenced and shaped by culture, itreflects culture. Because of cultural differences misunderstandings may arise,although the language used in communication may be faultless. So learning aforeign language well means more than merely mastering the pronunciations,grammars and vocabularies. It means learning to understand their culture.Today in China, it is important to incorporate culture teaching in Englishteaching. The research of culture teaching in English language teachingmainly refers to three aspects, the necessity to teach, what to teach and howto teach. This article reviews briefly the definitions of culture and introducesthe relation between culture and language. It also states the content of cultureteaching and the objectives of culture teaching and the strategies of cultureteaching. It further expounds that the final objective is to achieve thelanguage acquisition of English-learners through culture teaching.Key words: culture; language; culture teaching摘要:语言是文化的基石,没有语言,文化就无法存在。
Effect of Culture Parameters on the Growth of Sparassis crispaMyceliumThe effect of carbon and nitrogen sources, pH, temperature and substrate water content on the growth and vigor of Sparassis crispa mycelium was evaluated. Mycelial growth rates were highest when rice starch served as the carbon source and when peptone, yeast extract or soybean meal were adopted as the nitrogen source. The optimum pH and substrate water content values were 5.25 and 62.5% respectively. Mycelial growth was optimal at 20.2 ℃and inhibited at 35 ℃, and temperatures of 40 ℃and above killed the fungus.Sparassis crispa;Mycelial growth;Culture parametersSparassis crispa (Wulf.)Fries is a rare, edible fungus that produces a highly nutritious, crisp and tender fruit body. Sporophores may contain up to 2.6% polysaccharide which is 3~4 fold higher compared with Ganoderma lucidum. The mushroom grows on the ground of mature pine forests or at the base of dead pine trees where the fruit body stipe is attached to decayed roots. It is a brown rot fungus and nutrients are derived from the degradation of cellulose[1]. S. crispa is distributed in Heilong jiang, Jilin, Xizhang, Yunnan, Fujian, Hunan and Hubei Provinces of China [1-4], as well as in the United States, Canada, Australia, southern parts of the United Kingdom and on the Japanese islands of Honshu, Shikoku and Hokkaido. Although S. crispa is widely distri buted geographically, it is not found in large numbers. Research on this mushroom in China is at an early stage and we have now studied the effect of carbon and nitrogen sources, pH, temperature and substrate water content on mycelial growth in order to provide further scientific support for high yield cultivation.1 Materials and Methods1.1StrainSparassis crispa, strain C2004, was obtained from the Plant Protection Institute, Fujian Academy of Agricultural Sciences.1.2Methods1.2.1Effect of carbon sourceMycelial growth rates and vigor were determined using a basal medium consisting of (/L): 1.0 g KH2PO4,2.0g(NH4)2SO4,0.5g MgSO4 and 20g agar supplemented separately with 2% (w/v) glucose, sucrose, maltose, sticky rice starchor methylcellulose. Basal medium without added carbon source served as the control. Plates were inoculated in the center with a 6 mm dia. agar disc covered with fungal mycelium and incubated at 20 ℃. Five replicates were used for each treatment.1.2.2Effect of nitrogen sourceMycelial growth rates and vigor were determined using a basal medium consisting of (/L): 20 g glucose, 1.0 g KH2PO4,0.5g MgSO4 and 20g agar supplemented separately with 0.2% (w/v), (NH4)2SO4, KNO3, urea, peptone, yeast extract or soybean meal. Basal medium without added nitrogen source served as the control. Other procedures were as described in section 1.2.1.1.2.3Effect of temperatureMycelial growth rates and vigor on potato dextrose agar (PDA) medium consisting of (/L): 200 g potato, 20g gluose and 20 g agar were determined at 10 ℃, 15 ℃, 20 ℃, 25 ℃, 30 ℃, 35 ℃and 40 ℃. Other procedures were as described in section 1.2.1.WANG Jiancheng, YING Zhenghe, YU Yingrui, et al1.2.4Effect of pHMycelial growth rates and vigor were determined on PDA medium adjusted to pH 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5 or 8.0 with either 1 mol/L HCl or 1 mol/L NaOH and incubated at 20 ℃. Other procedures were as described in section 1.2.1.1.2.5Effect of substrate water contentCultivation substrate consisted of: 73.5% pine sawdust, 25% sticky rice powder and 1.5% brown sugar. The water content (%) [water weight/(substrate dry weight+water weight)×100]was adjusted to 40%, 45%, 50%, 55%, 60%, 65% and 70% respectively. Tubes (30×200 mm) were filled with mixed substrate (each tube contained 15 g dry substrate) and inoculated with a 6 mm dia. agar disc covered with fungal mycelium. Since the substrate surface becomes dehydrated during autoclaving, 1 mL of sterilized water was added at the time of inoculation to promote mycelial extension. This has only a negligible impact on the overall water content value. Tubes were incubated at 20 ℃and mycelial growth and vigor were determined at periodic intervals. Five replicates were used for each treatment.1.2.7Statistical analysisCurvilinear equations were derived with the DPS data processing system software[5].2 Results and Analysis2.1Effect of carbon sourceThe nature of the carbon source signi ficantly affected growth of S. crispa mycelia (see Table 1 in the Chinese version). Highest growth rates and most luxuriant mycelia were observed when sticky rice powder served as the major carbon source. Vigorous growth was recorded on maltose, intermediate growth occurred on control plates and media supplemented with either glucose or sucrose, and no growth was observed when methylcellulose served as the carbon source. The relatively good growth observed on control plates may have been due to residual nutrients present in the inoculation disc.2.2Effect of nitrogen sourceMycelial growth was rapid and most luxuriant when peptone, yeast extract or soybean meal served as nitrogen source. Intermediate growth was observed on control plates and on media supplemented with either KNO3 or NH2SO4, and no growth was recorded when urea served as nitrogen source (see Table 2 in the Chinese version).2.3Effect of temperature on mycelial growth rate and vigorS. crispa mycelia grew over the temperature range 10-30 ℃. Within the 10-25 ℃range, mycelial growth was more rapid and more vigorous with increasing tem perature, whereas above 25 ℃, the growth rate decreased and the mycelium was less vigorous(see Table 3 in the Chinese version).Statistical analysis was used to construct a mathematical model in which temperature was an independent variable and mycelial growth rate was a dependent variable. The relativity equation: Y=-2.408+0.363X-0.009X2,F = 16.4104 *(P = 0.01546) that defined the relationship between temperature (X,℃) and mycelial growth rate (Y,mm/d) was obtained using the DPS data processing system software. The P value indicated that there was a significant relationship between incubation temperature and mycelial growth rate. Based on the marginal utility equation (Y = 0.363-0.018X) derived from the relativity equation above, a zero marginal utility value was obtained at a temperature value of 20.2 ℃at which the maximal mycelial growth rate (1.25 mm/d) was attained. Mycelium incu bated at 35 ℃for 20 d was unable to grow but remained viable, and growth recovered when the mycelium was subsequently transferred to 20 ℃for 15 d. However, incubation at 40 ℃for 20 d killed the fungus.2.4Effect of pH on mycelial growth rate and vigorS. crispa mycelia grew over the full range of pH values tested (4.0~7.5). Statistical analysis using the DPS data processing system software was again employed to construct a mathematical expression in which pH was an independent variable and mycelial growth rate was a dependent variable. In this case, the relativity equation, Y=-4.89+2.52X-0.24X2, F=54.78653**(P=0.0004) (see Fig. 1 in the Chinese version) that defined the relationship between pH (X) and mycelial growth rate (Y,mm/d) was obtained. The P value again indicated that there was a significant relationship between pH and mycelial growth rate. Based on the marginal utility equation (Y=2.52-0.48X) derived from the relativity equation, the marginal utility value was zero at pH 5.25 which resulted in the highest mycelial growth rate (1.725 mm/d).2.5Effect of water content on mycelial growth rate and vigorBoth mycelial growth rate and vigor were affected by substrate water content. Within the range 45%~65%, the mycelial growth rate increased with increasing water content. However, above 65%, mycelial growth rates decreased and growth was less vigorous. The relativity equation, Y=-8.2880+0.3252X-0.0026X2,F=82.99765**(P=0.00015) (see Fig.2 in the Chinese version) that defined the relationship between substrate water content (X, %) and mycelial growth rate (Y,mm/d) was obtained as above. The P value again indicated that there was a significant relationship between substrate water content and mycelial growth rate. Based on the marginal utility equation (Y = 0.3252-0.0052X) derived from the relativity equation, the marginal utility value was zero at a substrate water content value of 62.5% which resulted in the highest mycelial growth rate (1.88 mm/d).3 Discussion3.1 Of the C sources tested, S. crispa (strain C2004) mycelia grew most rapidly and more vigorously when either sticky rice starch or maltose served as the carbon source. Since the price of maltose is relatively high compared to sticky rice starch, the latter was the most economical of the two carbon sources for S. crispa mycelial growth during production.3.2 S. crispa (strain C2004) mycelia grew better on organic nitrogen sources. Peptone, yeast extract and soybean meal contain a full complement of amino acids that can be used directly by the fungal mycelium thereby allowing fast and vigorous growth. However, amino acid synthesis is required when inorganic nitrogen sources are used and some amino acids are either synthesized incompletely or not at all[6,7]thereby resulting in a slower fungal growth rate and a less vigorous mycelium. Using peptone or yeast extract as nitrogen source for S. crispa production incurs higher costs compared with the more economical and practical soybean meal.[1]LIU ZN. A kind of rare edible fungus Sparassis crispa [J]. Edible Fungi,1986(5):6 7. (in Chinese)[2]CHEN QW, XIA QX, MA LA, et al. An investigation on macro fungi in Hubei Province a list of Basidiomycotina fungi(Ⅱ) [J]. Journal of Hubei Agricultural College, 2002,22(2):153 157. (in Chinese with English abstract)[3]HUANG NL. Illustrated Handbook of Large Fungi in China[M]. Beijing: Chinese Agricultural Publishing House, 1998. (in Chinese)[4]LI JZ, LU CY, ZHONG YQ. The newly recorded species of the macrofungi resources from Hunan(2)[J].Journal of Natural Science of Hunan Normal University,1995,18(2):64 67. (in Chinese with English abstract)[5]TANG QY, FENG GM. Applied statistical analysis and DPS data processing system [M].Beijing:Science Press,2002:5. (in Chinese)[6]CHEN SL, GU WY, TAO WX. A study of carbon source on liquid culture of Grifola frondosa [J]. Edible Fungi,1999,21(6):3 5.(in Chinese)[7]LIN QX, CHEN JY. Effect of C sources and N sources on the mycelial growth of Lactarius deliciosus [J]. Acta Edulis Fungi,2002,9(1):44 46. (in Chinese with English abstract)。