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Milesson, Joel, and Erika Abrahamsson. "Geoenergilager Xylem : Visualisering och lönsamhet." Thesis, Linnéuniversitetet, Institutionen för bygg- och energiteknik (BE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-27037.
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Inom svensk process- och tillverkningsindustri finns det stora mängder spillvärme som sällan kommer till användning. Att hitta olika tekniska lösningar för att effektivt tillvarata denna spillvärme skapar både nytta ur ett hållbart perspektiv samt ur ett ekonomiskt perspektiv för företaget. I denna rapport presenteras en utarbetad beräkningsmodell i Excel. Beräkningsmodellen används för att uppskatta lönsamheten för anläggning av ett högtemperaturlager i berggrunden. Excel-filen ska kunna användas för företag som en första uppskattning om ett borrhålslager är ett alternativ för tillvaratagande av spillvärme. Utformningen av beräkningsmallen utgick från Xylems högtemperaturlager i Emmaboda. Beräkningsmallen testades på Xylems borrhålslager. Resultatet visar att 2166 MWh/år kan tas ut från lagret, vilket stämmer överens till 83 % med Xylems egna beräkningar. Borrhålslagrets verkningsgrad beräknades till 65 % vilket kan jämföras med de 68 % som Xylem kalkylerat med. Nyckelord: Borrhålslager, UTES-system, BTES-system, HT-BTES-system, geoenergi, spillvärme.
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Ismail, Ihab. "Function and Regulation of Xylem Cysteine Protease 1 and Xylem Cysteine Protease 2 in Arabidopsis." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11243.
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A functional water-conducting system, the tracheary elements of the xylem, is required to sustain plant growth and development. Tracheary element formation is dependent on many biological processes terminated by programmed cell death and cellular autolysis. The final two processes are probably dependent on the activity of hydrolytic enzymes such as XCP1 and XCP2 known to be expressed in tracheary elements during these final two processes. Thus, the transcriptional regulation of XCP1 and the function of XCP2 were investigated. Qualitative and quantitative assessments of GUS activity as directed by various fragments of the XCP1 promoter showed that a 237-bp internal region was able to drive GUS expression in a tracheary element-specific manner in Arabidopsis. A 25-bp deletion at the 3' end of this region abolished GUS expression. The 237-bp region served as bait in a yeast one-hybrid analysis. Screening of yeast colonies retrieved 109 putative positive interactions, which included a potential transcriptional regulator, indole acetic acid-induced protein 8 (IAA8). An auxin responsive element that potentially binds auxin responsive transcription factors was found within the 25-bp deletion. Cis-elements were predicted by Genomatix and Athamap computer programs. The cis-elements form pyrimidine and gibberellic acid responsive elements that can potentially bind Dof and Myb transcription factors, respectively. In an independent effort, attempts to develop a mapping population to isolate upstream regulators of XCP1 expression did not succeed. Functionally, tracheary element-specific expression of XCP2 in Arabidopsis suggested a specialized role for XCP2 in final phases of tracheary element differentiation. The function of XCP2 was assessed using T-DNA insertional mutants, post-transcriptional gene silencing, and through tracheary element-specific expression of the cysteine protease inhibitor, soyacystatin N in Arabidopsis. Our findings revealed that the absence of XCP2 expression due to T-DNA insertional mutagenesis did not affect plant growth and development in the laboratory. Soyacystatin N was an effective in vitro inhibitor of cysteine proteases. Plants expressing 35S-driven cytosolic form of soyacystatin exhibited stunting and reduced apical dominance. Plants expressing pXCP1-driven cytosolic soyacystatin did not differ from wild type plants. Additionally, transgenic plants expressing pXCP1- and 35S-directed XCP2-double-stranded RNA for the silencing of XCP2 showed no unusual phenotypes compared to their wild type counterpartsPh. D.
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Courtois-Moreau, Charleen Laetitia. "Programmed Cell Death in Xylem Development." Doctoral thesis, Umeå universitet, Umeå Plant Science Centre, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1831.
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Concerns about climate changes and scarcity of fossil fuels are rising. Hence wood is becoming an attractive source of renewable energy and raw material and these new dimensions have prompted increasing interest in wood formation in trees, in both the scientific community and wider public. In this thesis, the focus is on a key process in wood development: programmed cell death (PCD) in the development of xylem elements. Since secondary cell wall formation is dependent, inter alia, upon the life time of xylem elements, the qualitative features of wood will be affected by PCD in xylem, about which there is little information. This thesis focuses on the anatomical, morphological and transcriptional features of PCD during xylem development in both the stem of hybrid aspen, Populus tremula (L.) x tremuloides (Michx.) and the hypocotyl of the herbaceous model system Arabidopsis thaliana (L. Heynh.). In Populus, the progressive removal of organelles from the cytoplasm before the time of death (vacuolar bursts) and the slowness of the cell death process, illustrated by DNA fragmentation assays (such as TUNEL and Comet assays), have been ascertained in the xylem fibres by microscopic analyses. Furthermore, candidate genes for the regulation of fibre cell death were identified either from a Populus EST library obtained from woody tissues undergoing fibre cell death or from microarray experiments in Populus stem, and further assessed in an in silico comparative transcriptomic analysis of Arabidopsis thaliana. These candidate genes were either putative novel regulators of fibre cell death or members of previously described families of cell death-related genes, such as autophagy-related genes. The induction of the latter and the previous microscopic observations suggest the importance of autophagy in the degradation of the cytoplasmic contents specifically in the xylem fibres. Vacuolar bursts in the vessels were the only previously described triggers of PCD in the xylem, which induce the very rapid degradation of the nuclei and surrounding cytoplasmic contents, therefore unravelling a unique previously unrecorded type of PCD in the xylem fibres, principally involving autophagy. Arabidopsis is an attractive alternative model plant for exploring some aspects of wood formation, such as the characterisation of negative regulators of PCD. Therefore, the anatomy of Arabidopsis hypocotyls was also investigated and the ACAULIS5 (ACL5) gene, encoding an enzyme involved in polyamine biosynthesis, was identified as a key regulator of xylem specification, specifically in the vessel elements, though its negative effect on the cell death process. Taken together, PCD in xylem development seems to be a highly specific process, involving unique cell death morphology and molecular machinery. In addition, the technical challenges posed by the complexity of the woody tissues examined highlighted the need for specific methods for assessing PCD and related phenomena in wood.Oron för klimatförändringar och brist på fossila bränslen har ökat påtagligt under de senaste åren. De enorma möjligheter som skogsråvaran erbjuder som alternativ källa för förnyelsebar energi och råmaterial har väckt ett stort intresse också för den biologiska processen bakom vedbildning i träd. Denna avhandling fokuserar på en viktig process i vedbildning: programmerad celldöd (PCD) i xylemet. Xylemcellernas livstid påverkar bildningen av sekundära cellväggar, vilket i sin tur påverkar vedens kvalitativa egenskaperna, så som veddensitet. Trots dess betydelse för viktiga egenskaper hos vedråvaran existerar fortfarande väldigt lite information om xylem PCD på cellulär eller molekylär nivå. I den här avhandlingen belyses de anatomiska, morfologiska och genetiska aspekterna av PCD i xylemutveckling i både stam av hybridasp, Populus tremula (L.) x tremuloides (Michx.) och hypokotyl av det örtartade modellsystemet Arabidopsis thaliana (L. Heynh.). Xylemet i både Populus och Arabidopsis består av två olika celltyper; de vattentransporterade kärlen och de stödjande fibrerna. Det är känt att celldöd i kärlen pågår mycket snabbt efter att den centrala vakuolen brister och de hydrolytiska enzymer släpps in i cytoplasman. I den här avhandlingen ligger fokus på fibrerna i Populus xylemet. Med hjälp av mikroskopianalyser av cellmorfologin (elektronmikroskopi) och DNA-fragmentering i cellkärnan (TUNEL- och Comet-analyser) kunde vi konstatera att till skillnad från kärlen så uppvisar fibrerna en långsam och progressiv nedbrytning av organellerna och cellkärnans DNA före vakuolbristning. Dessutom har kandidatgener för reglering av fibercelldöd identifierats antingen från ett Populus EST bibliotek från vedartade vävnader som genomgår fibercelldöd eller från mikroarray experiment i Populus stam. Dessa kandidatgener är antingen potentiella nya regulatorer av fibercelldöd eller medlemmar av tidigare beskrivna familjer av celldödsrelaterade gener. Bland de sistnämnda finns autofagi-relaterade gener, vilket stöder funktionen av autofagi i samband med autolys av cellinnehållet i xylemfibrerna. Dessa studier pekar därför på en typ av PCD som har inte tidigare beskrivits för xylemet. Arabidopsis är ett alternativt växtmodellsystem för studier av vissa aspekter av vedbildningen, såsom karakteriseringen av negativa regulatorer av PCD. Därför har också hypokotylanatomin analyserats, och ACAULIS5 (ACL5) genen, som kodar för ett enzym i biosyntesen av polyaminer, har visats vara en viktig regulator av xylemspecifikation genom dess negativa effekt på kärlens celldöd. Sammantaget visar denna avhandling att PCD i xylemutvecklingen verkar involvera unika morfologiska och molekylära mekanismer. Vi visar dessutom att komplexiteten hos de vedartade vävnaderna leder till ett behov av bättre anpassade verktyg för att djupare kunna bedöma PCD och liknande fenomen i veden.
Även med namnet Moreau-Courtois, Charleen L. samt Moreau, Charleen.
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Ramchander, Krithika. "Development of xylem-based water filters." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104270.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references.
Diarrheal diseases caused due to microbial contamination are one of the leading causes of fatalities amongst children. Despite the availability of numerous commercial products for water filtration and treatment, there continues to be a need for technological solutions that can make safe drinking water affordable and accessible. Due to their low cost, high filtration rate per unit weight and the ability to be manufactured locally with little infrastructure, xylem-based filtration devices have potential to address the challenge of microbial contamination of water in resource-limited settings. Previous studies by Boutilier et al. have demonstrated the ability of sapwood xylem from conifers to achieve up to 99.9% rejection of bacteria from water. However, it has been reported that drying of xylem after extraction leads to a drop in permeability by a factor of over 100. This poses a huge challenge in the context of transportation and storage of these filters. Maintaining the filters in a wet state would require special packaging and also reduce their shelf-life. Further, previous tests with the xylem filters at laboratory scale have involved the use of gas-pressure to drive the flow. In practical applications, the use of pumps would drive up the cost of the device negating the primary advantage of these filters. To keep operational costs as minimal as possible, it is critical to operate xylem filters offline. This thesis aims to address the challenge of dry storage and offline, gravity-based operation of xylem filters. Moreover, the use of xylem for water filtration has not been explored before and little is known about its performance characteristics. This thesis also seeks to advance the understanding of xylem as a filter material through the study of attributes such as degradation of xylem when soaked in water, filter lifetime, its variation with water quality and variation of flow rate with time. Methods to engineer the xylem filters to improve their rejection capability have also been discussed. In parallel to technology development, efforts were also made to identify avenues for implementation of these filters in India. The insights gathered from field visits to India and discussions with key stakeholders have also been presented..
by Krithika Ramchander.
S.M.
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Galicki, Stanley J., Gregg R. Davidson, and Stephen T. Threlkeld. "Element Mobility In Bald Cypress Xylem." Tree-Ring Society, 2008. http://hdl.handle.net/10150/622564.
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Trace element mobility in bald cypress (Taxodium distichum) was investigated for a suite of
elements using cores from century-old trees from a wetland in Humphreys County, Mississippi.
Element mobility was determined by comparing the dendrochemistry of decadal increments over the life span of a tree, and by comparing increments of the same age collected from the same tree during two different seasons. Variability within growth increments at the time of sampling was evaluated by comparing cores from the same tree collected at three points around the bole. Of 42 elements analyzed, eight were found above detection limits (As, Ca, K, Mg, Mn, Na, P, Zn). Clear evidence of translocation of P and Mn to the sapwood and K, Mg, and Na to the heartwood was observed. Ca and Zn were found with higher average concentrations in the sapwood, though evidence of translocation to the sapwood was equivocal. Arsenic did not vary significantly through any individual core. Variation in concentration was not found to be significant for any element with respect to year of sampling, season, location in the wetland, or position around the bole. With the exception of As, variation was significant with respect to increment age (decade) and location within the heartwood or sapwood.
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Schauer, Anke. "Komplexierung von Nickelionen an Pektin." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964609770.
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Sridhar, Varshini. "Proteomic studies of grape xylem tissue and sap." Thesis, Florida Agricultural and Mechanical University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1594029.
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Pierce’s disease (PD), caused by bacterium Xylella fastidiosa, seriously hampers the cultivation of Vitis vinifera also known as bunch grapes, in different parts of the world. The bacterium clogs xylem vessels and forms a biofilm, resulting in the wilting of the plant. Bunch grape cultivars exhibit certain degree of tolerance to PD, however most commercial cultivars suffer heavy loss due to this devastating disease. Therefore, studies on genetic variation for disease tolerance will assist in identification of key molecular components that confer tolerance to PD. Vitis species, such as, Florida hybrid bunch (FH) and muscadine grape ( Vitis rotundifolia) are widely cultivated in southeastern United States, and are known for their tolerance to PD. A detailed proteomic profile study of contrasting grape species is vital to understand the biological molecules associated with the PD tolerance. However information on total protein composition of Vitis xylem and sap is limited. The overall goals of this study are to determine the signal sequences associated with xylem and sap for the delivery of therapeutic proteins to control Xylella fastidiosa. The specific objectives of this research project are: 1) to compare the proteome profiles of xylem tissue and xylem sap from PD tolerant and -susceptible grapevine cultivars, and 2) to determine the role of proteins in the tissue and sap associated with PD tolerance mechanism. In this study, we used Bunch, FH, and Muscadine grape cultivars to characterize differentially expressed and unique proteins. Differentially expressed proteins were identified using LC MS/MS spectrometry searched against Vitis database. A total of 2519 and 402 proteins were identified in xylem and sap respectively, of which 151 proteins were common to both tissues. Bunch, FH, and muscadine sap showed 52, 53, and 30 unique proteins respectively. The cluster dendrogram analysis of the sap proteome showed that all of the Vitis species are bifolious. Based on the aforementioned, Florida hybrid bunch and muscadines are more closely related to each other than to bunch grape. Functional analysis and gene ontology revealed that proteins involved in carbohydrate metabolic process are more abundant in bunch grape, while FH and muscadine grape have more defense related proteins. Therefore, it is plausible to conclude that major functions of sap proteins in Bunch, FH, and Muscadine grapes are carbohydrate metabolic process and proteolysis (23%), protein phosphorylation (38%), and oxidation and reduction process (16%), respectively. Proteins involved in the defense and peroxidase activity are abundantly present in xylem and sap of FH and muscadine, and these proteins are relatively in reduced levels in bunch xylem and sap. Together, our findings highlight the possible roles of the identified unique proteins towards PD tolerance to Florida hybrid bunch and muscadine cultivars.
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Gilliham, Matthew. "Regulation of ion loading to maize root xylem." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620512.
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Watson, Richard James. "The development of a novel technique for sampling xylem sap from intact, transpiring plants using Philaenus spumarius, a xylem-feeding insect." Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391384.
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Many approaches have been employed to extract xylem sap from plants but uncertainty remains about exactly what is sampled by these methods and the extent to which extracted fluid reflects the content of the transpiration stream. The aim of this thesis was to develop a new technique for sampling xylem sap from intact, transpiring plants, using the common spittlebug Philaenus spumarius, a xylem-feeding insect. Continuous monitoring of the insect's excretion rate was achieved through a balance system connected to a computer. Using this procedure, it was demonstrated that P. spumarius feeds from the main transpiration stream and it was shown that P. spumarius can feed against xylem tensions more negative than previously realised. The relationship of the fluid extracted by P. spumarius to xylem sap was tested r through a xylem perfusion system. The concentration of the inorganic ions tested was not altered by the insect's metabolism. In addition, ABA was detected in the excreta and an increase in excreta ABA content was shown in water-stressed plants. The P. spumarius technique was used to demonstrate the xylem dynamics of Ca2+, ABA, and diurnal cycles of ion composition in intact, transpiring plants. In conclusion, P. spumarius represents a powerful vehicle for the quasi-continuous and quasi-non-invasive extraction of xylem sap from intact, transpiring plants.
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Bollhöner, Benjamin. "Significance of hydrolytic enzymes expressed during xylem cell death." Doctoral thesis, Umeå universitet, Institutionen för fysiologisk botanik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-81340.
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Xylem is an inherent feature of all vascular plants and functions in water transport and mechanical support. In order to efficiently transport water, xylem cells are reinforced by secondary walls before they undergo programmed cell death and their cell contents are removed by autolysis to create a hollow tube. During their differentiation, xylem cells express various hydrolytic enzymes, such as proteases, nucleases and lipases, but only in a few examples has their role in xylem cell death been characterized. This thesis focuses on the regulatory aspects of xylem cell death and the autolytic cell clearance in vessel elements and fibers of hybrid aspen (Populus tremula L. x tremuloides Michx.) and in vessel elements of Arabidopsis thaliana. Using comparative transcriptomic analysis, candidate genes for fiber-specific cell death processes were identified. Further, a hypothesis is presented on the regulation of thermospermine levels in the vasculature by a negative feedback-loop involving auxin and the class III Homeodomain-Leucine Zipper (HD-ZIP III) transcription factor HOMEOBOX8 (PtHB8). The role of the Arabidopsis METACASPASE9 (AtMC9) in xylem cell death was characterized using molecular tools, such as reporter lines and fluorescent fusion proteins, and electron microscopy (TEM). This showed that cell death initiation is not controlled by AtMC9. Instead, evidence is presented for the involvement of AtMC9 in the post mortem autolysis of vessel elements that follows tonoplast rupture and leads to the formation of the hollow conduit. Cell death-associated genes were further observed to be expressed during the emergence of lateral roots in Arabidopsis thaliana. This led to the discovery that cells overlying a lateral root primordium undergo cell death, which was demonstrated by detection of DNA degradation and TEM analysis. It is concluded that cell death facilitates emergence of lateral roots through the overlying tissues in a concerted manner with cell wall remodelling. Together, these findings show that although individual hydrolytic enzymes may be dispensable for plant growth and development, their common regulators are the tool for understanding their function and importance.Xylem är en karakteristisk vävnad i alla kärlväxter som leder vatten och mineraler samt har mekanisk stödfunktion. För att effektivt kunna transportera vatten förstärks xylemceller med sekundära cellväggar innan de dör genom programmerad celldöd. Deras cellinnehåll bryts ner genom autolys för att skapa ett ihåligt rör. Xylemceller uttrycker under sin differentiering olika hydrolytiska enzymer, såsom proteaser, lipaser och nukleaser, men bara för ett fåtal av dessa har funktionen under xylemcelldöd kartlagts. Denna avhandling fokuserar på reglering av xylemcelldöden och den autolytiska nedbrytningen av cellen, i såväl kärlelement och fibrer av hybridasp (Populus tremula L. x tremuloides Michx.) som i kärlelement av backtrav (Arabidopsis thaliana). Med hjälp av jämförande transkriptomanalys identifierades kandidatgener för fiber-specifika celldödsprocesser i hybridasp. Vidare utvecklades en hypotes om reglering av termosperminnivåer i vaskulaturen genom en negativ feedback-loop, som omfattar auxin reglering och klass III homeodomän-leucinzipper (HD-ZIP III) transkriptionsfaktorn HOMEOBOX8 (PtHB8). Funktionen av Arabidopsis METACASPASE9 (AtMC9) under xylemcelldöd karakteriserades med molekylära verktyg, såsom reporterlinjer och fluorescerande fusionsproteiner och elektronmikroskopi (TEM). Dessa analyser visade att celldödens initiering inte styrs av AtMC9. Istället presenteras bevis för en roll av AtMC9 i autolysen av kärlelement som sker post mortem efter att vakuolen har gått sönder och som slutför bildandet av det tomma kärlet. Genuttryck som associeras med celldöd observerades också under utvecklingen av laterala rötter i Arabidopsis thaliana. Detta ledde till upptäckten att celler som ligger ovanför ett lateralrotprimordium dör en programmerad celldöd och visar tecken på DNA-nedbrytning och autolys i TEM-analyser. Slutsatsen av denna studie är att celldöd i samspel med cellväggsmodifiering underlättar utväxten av laterala rötter genom de överliggande cellagren. Sammantaget tyder dessa upptäckter på att även om enstaka hydrolyserande enzymer inte är nödvändiga för växternas tillväxt och utveckling, så kan deras gemensamma reglering nyttjas för att förstå deras funktion och betydelse.
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Robson, David J. "Physical aspects of cavitation and freezing in conifer xylem." Thesis, University of Aberdeen, 1986. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU362721.
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Part I details work on cavitation, refilling and permeability of conifer xylem. Part II shows how conifers may avoid widespread cavitation during freezing of the xylem sap. PART I Cavitation was induced in sapwood samples by sealing wood in semi-permeable membranes and immersion in osmotic solutions. Emptying of up to 20-30% of the tracheids occurred for absolute pressures of between 1.0 x 105 N. m-2and -4 x 105 N m-2but very little further emptying occurred when the pressure was lowered to -9 x 105 N m-2. The limit of emptying found for this range of pressures indicates that one type of tracheid (earlywood or latewood) preferentially cavitates. It is suggested that the latewood cavitates more readily than the earlywood. Experimental tests showed that widespread refilling of cavitated tracheids only occurred when the xylem sap pressure was raised above the pressure in the cavitated tracheid lumens. Six theories to explain refilling of tracheids at the top of tall trees are considered. Of these capillary condensation, root pressure, refilling by ray parenchyma cells and capillarity are discarded on theoretical grounds. Experiments showed that temperature changes and temperature gradients did not cause refilling in equilibrated samples or in intact stem and root systems. Water absorption at the leaves appears to be the most likely method of refilling. Steady state liquid permeability measurements showed that xylem permeability decreased exponentially with increasing void volume for Douglas fir and Sitka spruce. The curves are probably not applicable to living trees because some liquid flowed through partially refilled tracheids. PART II Pressure rises up to 39 x 105 N m-2 and low freezing rates (1.75 to 2.3 pm s-1) were measured in freezing sapwood samples using implanted pressure transducers and thermistors. Electron micrographs of slowly frozen wood show bordered pit aspiration is not widespread during radial freezing. A finite element model of freezing in a single tracheid predicts pressure rises similar to those measured experimentally. This model also predicts that 5 to 8% of the water in the lumen migrates to other areas during freezing. However, in contradiction to experimental results, a model of whole stem freezing predicts freezing rates four times faster than the measured values. The low freezing rates measured experimentally indicate that bubbles only nucleate in the outermost layers of the xylem during freezing. However, if 5 to 8% of the lumen water migrates during freezing, low pressures on thawing may still cause cavitation. For this to be avoided it is suggested that water migrates from freezing tracheids to already frozen tracheids through narrow cell wall capillaries.
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Herrala, Steneros Jonathan, and Johan Olsson. "Utökat serviceintervall : Utökat serviceintervall för smältugnar hos Xylem Inc." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-63857.
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Syftet med denna studie var att finna en metod för Xylem inc, i Emmaboda, att mäta slitaget på ugnsinfodringen i deras smältugnar. Undersökningen genomfördes med hjälp av en kartläggning om hur gjuterier i Sverige mäter infodringen på sina smältugnar, vidare vilka produkter som finns på marknaden idag för att kunna finna den metod som passar bäst för Xylem inc. I huvudsak togs kontakt via telefon och mail med gjuterier och olika produkttillverkare samt ett besök hos Federal mogul, vilka har ett systemen som är i drift. Information från ett fungerande system är av intresse för undersökningen då en jämförelse är möjlig att göra för Xylem inc. Efter att data samlats in presenterades resultatet för Xylem inc. Därefter valde Xylem ut två system som de ville ha en lönsamhetsberäkning på. Lönsamhetsberäkningen visade att tiden det skulle ta att tjäna in investeringen var stor. Slutsatsen blev att det dyra systemet, SAVEWAY, är mest driftsäkert. Det är ett system som redan finns färdigt på marknaden och det bidrar dessutom till ökad säkerhet gällande anläggning och personal. Det billiga alternativet, Cobalt 3D Imager, är ett system som skulle kunna fungera bra med tiden förutsatt att man vidareutvecklar bitar gällande montering, tillvägagångssätt och automation.The purpose of this study was to find a method for Xylem inc, in Emmaboda, to measure the wear of the furnace lining in their melting furnaces. The survey was conducted using a mapping of how foundries in Sweden measure the lining on their melting furnaces, further on which products are available on the market today to find the method best suited for Xylem inc. Mainly contact was made via telephone and mail with foundries and various product manufacturers as well as a visit to Federal mogul, which has a system in operation. Information from a functioning system is of interest to the investigation as a comparison is possible for Xylem inc. After the data was collected, the results for Xylem inc were presented. Then Xylem selected two systems for which they wanted a profitability calculation. The profitability calculation showed that the time it would take to earn the investment was high. The conclusion was that the expensive system, SAVEWAY, is most reliable. It is a system that is already available on the market, and it also contributes to increased security regarding plant and personnel. The cheap option, Cobalt 3D Imager, is a system that could work well over time, provided you further develop pieces regarding assembly, approach and automation.
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Kim, Jong Sik. "Immunolocalization of Hemicelluloses in Differentiating Xylem of Cryptomeria japonica." Kyoto University, 2011. http://hdl.handle.net/2433/142344.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第16146号
農博第1882号
新制||農||991(附属図書館)
学位論文||H23||N4616(農学部図書室)
28725
京都大学大学院農学研究科森林科学専攻
(主査)教授 髙部 圭司, 教授 髙野 俊幸, 教授 杉山 淳司
学位規則第4条第1項該当
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Burgdorf, Martin. "Xylem-Saftfluss und Sauerstoffversorgung im Stamm von Betula pendula Einfluss von Xylem-Saftfluss und Gaskonzentrationen auf die Sauerstoffversorgung des Xylems von Betula pendula /." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983292728.
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Uroic, Miran Kalle. "The impact of arsenic species on the production and composition of xylem sap." Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=167822.
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The focus of this research was on the xylem sap of cucumber plants during arsenic stress. A better understanding of the uptake and translocation mechanisms within the plant is crucial for the assessment of arsenic impact on fruits and cereals of the human diet. The impact of four different arsenic species (As(III), As(V), DMA(V) and MMA(V)) on the xylem sap production and their respective concentration in the xylem was studied. Cucumbers behave similar under arsenic stress as other non-tolerant plant species regarding uptake and translocation; high inorganic uptake into the roots but higher translocation of methylated arsenic into shoots and leafs. In plant physiology spectroscopic techniques coupled to separation techniques are usually deployed for metal(loid) studies. These techniques are well known and used. However, their robustness might be a disadvantage when it comes to biological dynamic systems. To overcome this, voltammetry was used as a new technique for xylem sap and hydroponic nutrient solution analysis. Voltammetry was used to analyse the nutrient solution of hydroponically grown cucumbers and their xylem sap during arsenate treatment in order to detect weak arsenite complexes. Furthermore, assessment of complexation capacities and ligand concentrations were performed. In order to identify possible arsenite ligands, xylem sap was analyzed by metabolomics, a recently developed tool for analyzing biological samples. Here, xylem sap samples of arsenate stressed plants were compared with control plants to identify organic compounds which are up- or down-regulated due to arsenate stress. Nine m/z values were identified to be up- or down-regulated under arsenate stress of which five were used for identification. LC-MS spectra obtained by high-resolution LC-MS were used for identification of organic compounds regulated due to arsenate stress. Isoleucine was found to be down-regulated under arsenate stress.
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Danzer, Shelley R., Steven W. Leavitt, Irina P. Panyushkina, Andreas Mergner, Evelyn Garcia, and Valeria Best-Svob. "Xylem Tracheid Development in Pinus Resinosa Seedlings in Controlled Environments." Tree-Ring Society, 2001. http://hdl.handle.net/10150/262534.
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Progressive tree-ring xylem cell size changes may reveal the influence of changing environment during the growing season. This study examines xylem tracheid cell growth in red pine (Pious resinosa Ait.) seedlings grown in cabinets under controlled environment, where single parameters (temperature, light, soil moisture and CO2) were varied step-wise in each chamber at ca. 30-day increments for ca. 6 months. Control and temperature treatments were replicated. Cross-sections (20 μm thick) sliced with a sliding microtome from each of four seedling stems from each cabinet were mounted on glass slides. Lumen diameters and cell-wall thickness were measured on 4 orthogonal tracheid radial files on 4 radii of each stem. Mean cell sizes were 11-17 μm among treatments and growth periods, whereas numbers of cells formed averaged 0.2-1.3 cells per day. Cell size increased throughout the experiment in most of the treatments, including one of the control treatments and those with the greatest potential to limit growth (decreasing temperature, light and soil moisture). Soil moisture was the only environmental parameter that tended to cause late declining growth, and CO, up to 500 (μmol mol⁻¹ did not appear to influence cell development. Despite a substantial range of environmental shifts in the chambers (100 μmol mol⁻¹ CO₂; 125 μEinsteins m⁻² s⁻¹ light; 8 °C temperature; 35% relative humidity; watering every day to every 5th day), the continued stem elongation and cell-size increases indicate that conditions never became significantly limiting to growth in most treatments. Although the range of environmental variability is undoubtedly much greater in most natural red pine systems, these results indicate that fairly large variations in environment during development of juvenile wood in seedlings may not leave an imprint retrievable from cell-size measurements made on the earliest rings of mature trees.
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Cano, Delgado Ana Isabel. "Genetic and molecular analysis of xylem development in Arabidopsis thaliana." Thesis, University of East Anglia, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365009.
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Plant cell walls play a central role in cell growth and morphogenesis. All plant cells have a primary wall. The formation of a secondary cell wall is restricted to particular cell types, such as the xylem cells, highly lignified cells that provide support and transport functions to the plant. The mechanisms regulating secondary cell wall biogenesis remain largely unknown. To identify genes involved in such mechanisms, a genetic screen for mutants with altered xylem development in the primary root of Arabidopsis thaliana has been conducted. Three different classes of mutants were identified. They are characterised by increased number of xylem strands (m"), altered timing of protoxylem differentiation (tpx) and ectopic lignification (eh). Initial characterisation of the mutant phenotypes, establishment of different complementation groups and their map position in the Arabidopsis genome has been determined. Mutations in the EL [I locus have been characterised in further detail. The eli l mutants exhibited ectopic lignification of cells throughout the plant that never normally lignify. Xylem cells in elil were misshapen and failed to differentiate into continuous strands, causing a disorganised xylem. elil mutants also exhibited altered cell expansion resulting in a stunted phenotype. Abnormal distribution of cellulose and lignin was observed in elil cell walls. Ultrastructural analysis of elil cell walls using an anti-lignin antibody has revealed that that the ectopic deposition of lignin-like compounds occurs within an altered secondary wall. Furthermore, other previously described cell expansion mutants, such as lit, rswl (at the conditional temperature) and det3, exhibited lignification patterns reminiscent to that of elil mutants. Analysis of the genetic interactions of elil with the lit mutant revealed that ELlI and LIT genes act in independent pathways to control cell expansion. These results, together with the double mutant analysis of eli l with other cell expansion mutants suggested a link between cell growth and differentiation of secondary thickened walls. Map-based cloning placed the ELJ1 gene in a 140-Kb interval on the top arm of Arabidopsis chromosome V. A candidate gene approach was used that identified a gene encoding a cellulose synthase catalytic subunit (CesA), AthCesA-3 as a candidate. Sequence analysis revealed that the AthCesA-3 gene is mutated in two elil alleles sequenced, both mutations leading to amino acid substitutions. Initial complementation experiments of elil plants with the wild type AthCesA-3 gene appeared to restore the wild type phenotype, suggesting that mutations in the AthCesA-3 gene gave rise to the elil phenotypes. These studies represent an important contribution to our understanding of the molecular mechanism of cellulose deposition during cell expansion and secondary cell wall deposition during plant morphogenesis.
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Leoo, Hampus. "Genetic regulation of xylem specification and differentiation in Arabidopsis thaliana." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-445551.
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Ogata, Yoshiyuki. "STRUCTURAL ANALYSIS OF PERIODIC XYLEM GROWTH IN SELECTED TROPICAL TREES." Kyoto University, 2002. http://hdl.handle.net/2433/150363.
Full textAbstract:
Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第9240号
農博第1219号
新制||農||836(附属図書館)
学位論文||H14||N3609(農学部図書室)
UT51-2002-B747
京都大学大学院農学研究科森林科学専攻
(主査)教授 藤田 稔, 教授 野渕 正, 教授 伊東 隆夫
学位規則第4条第1項該当
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Yang, Suk-Hwan. "Transcript profiling of differentiating xylem of loblolly pine (Pinus taeda L.)." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1380.
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Wood formation (xylogenesis) is a critical developmental process for all woody land plants. As an initial step to understand the molecular basis for temporal and spatial regulation of xylogenesis and the effect of the expression of individual genes on physical and chemical properties of wood, microarray and realtime RTPCR analyses were performed to monitor gene expression during xylogenesis under various developmental and environmental conditions. The specific objectives established for this study were: Objective 1. Microarray analysis of genes preferentially expressed in differentiating xylem compared to other tissues of loblolly pine (see Chapter II); Objective 2. Microarray analysis of seasonal variation in gene expression for loblolly pines (Pinus taeda L.) from different geographical sources (see Chapter III); Objective 3. Realtime RTPCR analysis of loblolly pine AGP and AGPlike genes (see Chapter IV). Based on the results from this study, candidate genes may be further studied for association with significant traits, used for genetic modification of wood properties, or included in future studies to further examine the molecular mechanisms of wood
formation.
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Mujib, Malip. "Influence of xylem blockage on rooting of cuttings of Triplochiton scleroxylon." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334827.
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Ismond, Kathleen (Kaathleen Patricia) Carleton University Dissertation Biology. "Development of large diameter secondary Xylem Vessel Members; a new theory." Ottawa, 1996.
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Suren, Haktan. "Architecture and Evolution of Xylem-related Gene Coexpression Networks in Poplars." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/31523.
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With the advent of sequencing technologies, a variety of methods have been available day by day. Each of these methods have helped scientists to for a deeper understanding of the biological function and evolutionary constraints on the relevant genes, which can be gained through the use of modern computational approaches. Numerous approaches have being developed to advance these goals, and interaction network mapping is one of them. This method has been employed to study a variety of organisms to illustrate shared (conserved) or individual (unique) properties, and is mainly based on identifying and visualizing modules of co-expressed genes. As being a very strong candidate for such tools, co-expression gene network was used in this study to indentify the genes in wood formation of Populus trichocarpa with the help of the other novel bioinformatics tools such as Gene Ontology and Cytoscape.
In order to booster the accuracy of the findings, we have combined it with an evolutionary approach, synonymous and non-synonymous ratio (dN/dS) of the proteins to show the selective patterns of the genes in a comparative fashion between woody and non-woody plants.
This thesis is proposed to help plant scientists to gain insights into the genes that are involved in wood formation. By taking advantage of the computational studies have been done on this paper, one can validate the experiments along with reducing the cumbersomeness of the lab trials on the topic of wood formation in plantsMaster of Science
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Håkansson, Anton, and Jan Lundgren. "Underhållsplanering för pumpprovningsanläggning Q2 : Vid Xylem Water Solutions AB, Flygt Emmaboda." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-64583.
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Företaget Xylem Flygt i Emmaboda producerar dränkbara pumpar av olika storlek och typer som används i hela världen. Innan pumparna levereras till kund testas de i Xylem’s egna testanläggningar. Anläggningen Q2 som berörs i rapporten består av en bassäng med tillhörande rörsystem, ventiler, anslutningsutrustning och mätutrustning. Denna rapport undersöker och lägger fram förslag på förbättringsmöjligheter rörande testanläggningens underhållsplanering. Frågor som undersöks är, om anläggningen ser kvalitetsmässigt och utseendemässigt riktigt ut inför kundbesök, tidsintervaller mellan förebyggande underhåll, miljöansvar angående vattenbyte i bassäng, möjlighet att implementera resultatet på övriga anläggningar samt rekommendationer på uppföljning. Rapporten resulterade i checklistor till underhållsavdelning och operatörer av anläggningen, dokumentation av komponenter och förbättringsförslag.The company Xylem Flygt in Emmaboda produces submersible pumps of various sizes and types used worldwide. Before the pumps are delivered to the customer they are tested in Xylem's own testing facilities. The plant Q2 concerned in the report consists of a basin with associated piping, valves, connection equipment and measurement equipment. This reports main objective is to investigate and make proposals for improvement regarding test facility maintenance planning. Other questions examined areIf the plants looks representable in quality and appearance to the visiting customers, the time intervals between preventive maintenance, environmental responsibility regarding the change of water in the basin, the ability to implement the results in other facilities as well as recommendations on follow-up’s. The report resulted in checklists for the maintenance department and the operators of the facility, documentation of components and improvement proposals.
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Takeuchi, Miyuki. "Immunolocalization of enzymes involved in lignin biosynthesis in differentiating poplar xylem." Kyoto University, 2004. http://hdl.handle.net/2433/145414.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第11069号
農博第1434号
新制||農||896(附属図書館)
学位論文||H16||N3950(農学部図書室)
22601
UT51-2004-J741
京都大学大学院農学研究科森林科学専攻
(主査)教授 藤田 稔, 教授 伊東 隆夫, 教授 島田 幹夫
学位規則第4条第1項該当
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Liang, Jiansheng. "Xylem-carried abscisic acid (ABA) in plant responses to soil-drying." HKBU Institutional Repository, 1997. http://repository.hkbu.edu.hk/etd_ra/167.
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Serk, Henrik. "Cellular Aspects of Lignin Biosynthesis in Xylem Vessels of Zinnia and Arabidopsis." Doctoral thesis, Umeå universitet, Institutionen för fysiologisk botanik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-109179.
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Lignin is the second most abundant biopolymer on earth and is found in the wood (xylem) of vascular land plants. To transport the hydro-mineral sap, xylem forms specialized conduit cells, called tracheary elements (TEs), which are hollow dead cylinders reinforced with lateral secondary cell walls (SCW). These SCWs incorporate lignin to gain mechanical strength, water impermeability and resistance against pathogens. The aim of this thesis is to understand the spatio-temporal deposition of lignin during TE differentiation and the relationship with its neighbouring cells. In vitro TE differentiating cell cultures of Zinnia elegans and Arabidopsis thaliana are ideal tools to study this process: cells differentiate simultaneously into 30-50% TEs while the rest remain parenchymatic (non-TEs). Live-cell imaging of such TEs indicated that lignification occurs after programmed cell death (PCD), in a non-cell autonomous manner, in which the non-TEs provide the lignin monomers. This thesis confirms that lignification occurs and continues long after TE PCD in both in vitro TE cultures and whole plants using biochemical, pharmacological and cytological methods. The cooperative supply of lignin monomers by the non-TEs was demonstrated by using Zinnia and Arabidopsis in vitro TE cultures. Inhibitor experiments revealed further that the non-TEs supply reactive oxygen species (ROS) to TEs and that ROS are required for TE post-mortem lignification. Characterization of the non-TEs showed an enlarged nucleus with increased DNA content, thus indicating that non-TEs are in fact endoreplicated xylem parenchyma cells (XP). The cooperative lignification was confirmed in whole plants by using knock-out mutants in a lignin monomer synthesis gene, which exhibit reduced TE lignification. The XP specific complementation of these mutants led to nearly completely rescuing the TE lignin reduction. Using microscopic techniques, the spatial distribution of lignin was analyzed in TEs from in vitro cultures and whole plants, revealing that lignification is restricted to TE SCWs in both protoxylem and metaxylem. These specific deposition domains were established by phenoloxidases, i.e. laccases localized to SCWs and peroxidases, present in SCWs and the apoplastic space. Laccases were cell-autonomously produced by developing TEs, indicating that the deposition domains are defined before PCD. Altogether, these results highlight that the hydro-mineral sap transport through TEs is enabled by the spatially and temporally controlled lignification of the SCW. Lignification occurs post-mortem by the supply of monomers and ROS from neighbouring XP cells and is restricted to specific deposition domains, defined by the pre-mortem sequestration of phenoloxidases.
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Richardson, Peter. "Isolation and characterization of genes specific to differentiating xylem in Populus canescens." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428144.
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Petzold, Herman Earl III. "Promoter Deletion Analysis of Xylem Cysteine Protease 2 (XCP2) in Arabidopsis thaliana." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/32582.
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The process of xylem tracheary element differentiation involves the coordination of vascular cambium activity, cell fate determination, cell expansion/elongation, secondary wall synthesis, programmed cell death, and cellular autolysis. The end result of tracheary element differentiation is a cellular corpse lacking a protoplast and consisting of a thickened cell wall composed mostly of lignin and cellulose. Little is known about the genetic mechanisms regulating the process of tracheary element differentiation. XCP2 expression localizes to tracheary elements according to two independent methods of analysis: promoter reporter experiments and immunogold localization by electron microscopy. XCP2 may be involved in catalyzing the degeneration of the protoplast during the final autolytic stages of tracheary element differentiation. To this date XCP2 function has not been directly demonstrated. In principle, any tracheary element-specific markers can be linked to upstream regulatory genes with roles in tracheary element differentiation. To develop the XCP2 promoter as a tool for identification of transacting factors, a promoter deletion analysis was carried out. Utilizing information from 5â and 3â deletion constructs, a 70-bp region upstream of the XCP2 translational start site is both necessary and sufficient for TE-specific expression of the UidA reporter gene. Mutational analysis of the ACTTTA element at position -113-bp strongly suggests it is a cis element required for XCP2 expression. In silico analysis of an 18-bp promoter region located within 200-bp of the translation start site and including the ACTTTA element revealed high indentity shared between xylem-specific XCP2 homologs from Zinnia elegans, Populus trichocarpa, and XCP1 from Arabidopsis thaliana.Master of Science
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Bergman, Elisabeth Anne, and Elisabeth Anne Bergman. "Conquering the terrestrial environment: the evolution of xylem anatomy in early tracheophytes." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/626731.
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Since the first land plants appeared 480-360 million years ago, natural selection has resulted in continued colonization into increasingly drier and harsher environments. The evolution of traits associated with water transport and avoidance of embolisms allowed plants to conquer increasingly more seasonal and drier terrestrial environments. However, it is unclear just how the xylem anatomy of the first Embryophytes differed from extant (living) taxa and if these differences translated to differences in plant functioning. I measured and compared hydraulic traits from stem cross-sections from extant plants and extinct fossil specimens. For 231 stems comprising 115 extant and 116 extinct taxa, measures of xylem conduit diameter/frequency and segment diameter were measured. Comparing these measures of xylem conductive traits indicates that extant plants, for their size, have more and wider conduits leading to a larger total conductive area and higher rates of water conductance. Further, the combination of xylem traits found in extinct paleo plants suggests that they were less efficient at water transport and likely more restricted to less seasonal and more wet environments. Together, these results reveal a unique insight into the functioning of extinct paleo plants and the evolution of xylem form and function.
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Newman, Lisa J. "MYB misexpression links the spatial control of lignification with photomorphogenesis." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365719.
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Carden, David Eoin. "The cell physiology of barley salt tolerance." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298670.
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Cholewa, Ewa M. "Calcium transport and delivery to the xylem in onion (Allium cepa L.) roots." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0023/NQ51185.pdf.
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Eklund, Malin, and Fanny Steenari. "En mixers väg genom produktionsflödet : En Value Stream Mapping på OPX Xylem Emmaboda." Thesis, Linnéuniversitetet, Institutionen för ekonomistyrning och logistik (ELO), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-35705.
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Bakgrund: Den svenska produktionsindustrin hotas utav så kallade låglöneländer som kanerbjuda samma tillverkning med en högre lönsamhet. Detta gör att verksamheten måste varaattraktiv för såväl investerare som kunder vilket gör att företaget måste genomföra ständigaförbättringar för att klara konkurrensen. Detta är något som även Xylem i Emmaboda kännerav. Xylem tillverkar ett brett utbud av dränkbara vattenpumpar men även annan utrustningsom krävs för att leverera vattenteknologi. Tidigare studier på en utav Xylems verkstäderOPX har visat att produktionen lägger mycket tid på aktiviteter som inte är värdeskapande såsom materialhantering och andra förflyttningar genom fabriken. Syfte: Syftet med uppsatsen är att identifiera var det kan finnas slöserier genom att utföra enValue stream mapping på en utav Xylems verkstäder i Emmaboda. Metod: Arbetet består av en fallstudie med explorativt syfte som utförs genom en Valuestream mapping. En kvalitativ forskningsmetod med insamling av såväl kvalitativa somkvantitativa data, genom observationer, intervjuer, litteraturstudier och tidsstudier hargenomförts. Resultat, slutsatser: Uppsatsen resulterade i en nutidskarta över bana 102 på OPX som i vilken en del mindre slöserier identifierades. Dock gav inte den valda metoden Value stream mapping önskat resultat då de upplevda slöserierna ifrån fallföretagets sida inte kunde identifieras. Utifrån detta drar författarna slutsatsen att en annan metod med utgångspunktifrån de upplevda problemen borde ha valts eller att de upplevda slöserierna inte grundar sig iden utvalda tillverkningsbanan.
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Potash, Benjamin R. "Characterization and preservation techniques of plant xylem as low cost membrane filtration devices." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92069.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from PDF student-submitted version of thesis.
Includes bibliographical references (pages 62-64).
Safe drinking water remains inaccessible for roughly 1.1 billion people in the world.³⁴ As a result, 400 children under the age of 5 die every hour from biological contamination of drinking water.³⁴ Studies have been done to show that plant xylem from the sapwood of coniferous trees is capable of rejecting 99.99% of bacteria from feed solutions.16 Additionally, 4 L/d of water can be filtered with a ~ 1 cm² filter area using a transmembrane pressure of 5 psi, an amount sufficient to meet the drinking needs of one person. However, the main drawback of xylem is that its permeability drops by a factor of 100 or more after being left out to dry for only a few hours. This paper seeks to characterize the performance of the xylem as a filter, determine the minimum length at which the xylem is effective for filtering bacteria, and increase the xylem's ability to rewet (retaining its permeability and rejective capabilities) after drying through the use of polymer coatings. Finally, potential techniques for decreasing the minimum particulate size the xylem can filter are discussed, with the aim of allowing the membrane to filter viruses.
by Benjamin R. Potash.
S.B.
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HULTENBERGER, HILDA. "Capturing customer value with product service systems. : A case study at Xylem Inc." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263129.
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Competition among original equipment manufacturers are increasing and firms are looking for new ways to compete without dumping the prices. A growing approach is to move from selling traditional products into solutions with a combination of product and services by offering product service systems (PSS). This can provide business opportunities and strengthen the relationship with existing customers, but to reap the rewards there are both internal and external challenges that the firm needs to overcome, they also need to look at new ways of working to be able to handle the increased complexity of selling solutions. This master thesis has investigated how Xylem should approach servitization from a customer oriented perspective. It also discusses how the incentives and challenges for servitization for customers differ depending on segment and compared to literature. Through a combination of existing literature and qualitative interviews with Xylems customer it has been possible to identify the key components and drivers for when a customer is mature to approach servitization. It has resulted in an alternative list and ways of approaching servitization where the customer characteristics are taken into consideration. The findings from this thesis highlight a number of critical customer characteristics that need to be considered. It shows the importance of understanding a larger part of the customers business model when selling a product service system compared to when selling a product.Konkurrensen mellan original utrustnings tillverkare tätnar och firmor letar efter nya sätt att tävla utan att dumpa priserna. Ett växande sätt att hantera det är att övergå från att sälja traditionella produkter till att sälja lösningar som består av en kombination av produkter och tjänster genom att erbjuda produkt- och tjänstesystem (PSS). Det här kan erbjuda affärsmöjligheter and stärka kundrelationen, men för att kunna skörda frukterna av detta så måste firman övervinna både interna och externa utmaningar. De behöver även titta på nya sätt att hantera den ökade komplexiteten som kommer med att sälja lösningar. Det här mastersarbetet har undersökt hur Xylem bör närma sig tjänstefiering från ett kundorienterat tilltalssätt. Det diskuterar även hur drivkrafterna och utmaningarna för tjänstefiering varierar beroende på segment and jämfört med litteraturen. Genom en combination av existerande litteratur and kvalitativa intervjuer med Xylems kunder hard et blivit möjligt att identifiera nyckelkomponenter och drivkrafter för när kunderna är mogna nog att närma sig tjänstefiering. Det här har resulterat i en alternativ lista och angreppssätt när det kommer till tjänstefiering där kundprofilen tas med i bejakande. Slutsatsen betonar ett antal kritiska kundegenskaper som behöver ta i åtanke. Den visar också hur viktigt det är att förstå en större del av kundens affärsplan när man säljer ett produkt- och tjänstesystem jämfört med när man säljer en produkt.
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Arkhurst, Bettina K. "Identification and evaluation of techniques for quality control of low-cost xylem filters." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120268.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 49-51).
2.1 billion people worldwide, majority of whom are of the poorest income quintile, lack access to safe, readily available water in their homes. The need for affordable, decentralized methods of water filtration led to the development of a low-cost membrane filter produced from the xylem of coniferous trees. Due to xylem structure variation and the potential for improper filter processing during mass production, quality control protocols are a necessity. Manufacturers must ensure xylem filters are functional in terms of microbial rejection and adequate flow rates. Testing methods similar to those mentioned in this thesis can also be developed for other membrane filters. The suitability of two fluids, water and air, were evaluated for use in the quality control process. For testing using water, turmeric and blue dye were used to create a visual indication test to detect a filter's major failures. We found that this method has the potential to detect both leaks and improperly prepared filters, but it lacks affordable, quantitative analysis for determining rejection percentages. Air was found to be a viable option for xylem filter testing at pressures of 6 psi and above, though presence of the xylem lowered the concentration of particles detected at the outlet by one-fourth. The substances found to be most suitable for testing the filter were Baker's yeast, jeweler's rouge, turmeric, and buttermilk given their affordability, particle/microbe size, and availability. Further exploration is required to determine the optimal particle to use in water and air testing and the equipment necessary for the quality control process to be implemented.
by Bettina K. Arkhurst.
S.B.
38
Wheeler, James K. "Water transport, embolism recovery and water storage in trees." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11256.
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The ability to maintain hydraulic continuity in the xylem is essential to supply leaves with the water that must be exchanged for carbon dioxide. The metastable nature of xylem sap causes this system to be inherently vulnerable to failure by rapid vaporization within the conduits. Much of the recent work on hydraulic architecture and cavitation has pursued the elusive mechanism behind apparent hydraulic recovery concurrent with tension in the bulk of the xylem, referred to as "novel refilling". An investigation into the dynamics of this behavior (Chapter 3) revealed two key artifacts that can produce the appearance of novel refilling when in fact no embolism (and therefore, no recovery) has occurred. A further implication of these artifacts is that plant xylem may be more robust against embolism than previously expected. In the absence of novel refilling, it becomes much harder to reconcile the extreme vulnerability reported for ring porous species. Studies of Robinia pseudoacacia (Chapter 4) address whether the artifacts illuminated in chapter 3 provide insight into the ongoing debate about the cavitation resistance of long-vesseled species and whether it is possible to accurately assess cavitation resistance in these species using the centrifuge method. Root pressure, as an alternative to novel refilling, provides plants with a means of reversing cavitation. Studies of Betula papyrifera (Chapter 5), however, show that recovery from embolism by root pressure is limited to early spring and point to an important role for water storage in fibers that minimizes xylem tensions and thus the risk of cavitation.
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Zhao, Chengsong. "Identifying and characterizing genes that regulate vascular tissue-specific functions." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/28024.
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Vascular tissues provide both the mechanical support to the plant body and the conducting cells for the transport of water, mineral solutes, hormones and other signaling molecules, amino acids, and sugars. To identify genes that may regulate vascular tissue-specific functions, we isolated xylem, phloem-cambium, and nonvascular tissues from the Arabidopsis root-hypocotyl, performed a genome-wide comparative analysis of tissue-specific transcripts using the 24K Affymetrix Arabidopsis ATH1 Genome Array (24K GeneChip), and identified potential genes that are required for xylem and phloem differentiation or tissue-specific functions.
Based on this comparative analysis, two phloem-specific G2-like transcription factors, MYR1 and MYR2, and a xylem-specific NAC domain family member, XND1, were selected for further characterization. Under continuous light, myr2 plants flowered early, while myr1 plants did not differ significantly from wild type controls. However, double mutant myr1myr2 plants exhibited a novel phenotype characterized by elongated petioles, semi-erect leaf orientation, and suppression of lateral shoot outgrowth. These characteristics are reminiscent of yucca, a dominant Arabidopsis mutant with elevated levels of free auxin. Preliminary results indicated that like yucca, myr1myr2 plants were more resistant than wt plants to 5-mT, a toxic tryptophan analog, suggesting that MYR1 and MYR2 may be involved in regulating tryptophan-dependent auxin biosynthesis. Overexpression of any one of MYR1 isoforms resulted in a phenotype that in some cases resembled that observed in the double mutant, indicating that the regulation mediated by MYR1 and MYR2 may depend on formation of specific heterodimers consisting of isoforms of MYR1 and/or MYR2, and that the dimerization was susceptible to disruption both by overexpression and loss-of-function of MYR1/MYR2.
Overexpression of XND1 resulted in the absence of TEs as determined from the absence of both secondary cell wall deposition and TE death. Using 3 tissue-specific promoter-GUS lines as genetic backgrounds, we demonstrated that overexpression of XND1 suppressed only TE-specific GUS expression but not phloem-specific GUS expression. Three T-DNA/transposon insertion lines, xnd1-1, -2, and -3, were identified. Under normal conditions, xnd1 did not exhibit significantly different growth and development compared to wild type plants. However, preliminary data indicated that xnd1 plants were ABA and cold hypersensitive. Yeast-two hybrid screening using the N-terminal portion of XND1 as bait identified a novel RING finger protein, At3g62970 that may function as the ubiquitin ligase (E3). These results suggested that XND1 functions as a negative regulator of xylem cell differentiation, and that the regulation mediated by XND1 may be integrated with the ubiquitin/26S proteasome pathway.Ph. D.
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Vinya, Royd. "Stem hydraulic architecture and xylem vulnerability to cavitation for miombo woodlands canopy tree species." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:9028b995-5379-4969-8a7b-59a7aa7ab533.
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Africa's miombo woodlands constitute one of the most important dry tropical forests on earth, yet the hydraulic function of these woodlands remains poorly researched. Given the current predictions of increased aridity by the end of this century in the miombo ecoregion, understanding the likely response of miombo woodlands tree species to water stress is crucial in planning adaptation strategies. Predicting the response of miombo woodlands to future climate trends is hampered by a lack of knowledge on the physiology of the common miombo woodlands tree species. In particular, plant-water relations for this woodlands type are not well understood. An understanding of plant-water relations for this woodlands type will provide insights into how water limits tree species distribution in this ecosystem. This will also improve our prediction model on the likely response of this ecosystem to predicted climate change. For this reason, the overall objective of this research was to evaluate the hydraulic architecture and xylem vulnerability to cavitation for nine principal miombo woodlands tree species differing in drought tolerance ability and habitat preference. This was achieved by; examining the hydraulic properties and evaluating the extent to which each hydraulic design was vulnerable to water stress-induced xylem cavitation; investigating how seasonal changes in plant-water relations influences seasonal patterns of leaf display and; analyzing the relationship between stem hydraulic supply and leaf functional traits related to drought tolerance ability. This research has found that drought-intolerant tree species with mesic specialization have more efficient stem hydraulic systems than co-occurring habitat broad ranging species. Broad ranging tree species attain wider habitat distribution by adjusting their hydraulic supply in response to changing ecosystem water availability. The finding that hydraulic properties differ significantly between tree species with contrasting habitat preference suggests that tree hydraulic design may have some adaptive ecological role in influencing species habitat preferences in miombo woodlands. The evaluation of xylem vulnerability to cavitation revealed that mesic specialized tree species were more vulnerable to water stress-induced cavitation than habitat broad ranging tree species. Vulnerability to cavitation in individuals from the same broad-ranging species growing in contrasting habitats showed only marginal and statistically insignificant (P > 0.05) differences between wet and dry sites. In the investigation of the influence of seasonal changes in stem water relations on seasonal leaf display, seasonal rhythms in stem water status were found to exert significant controls on leaf phenology. Mesic specialists had strong stem water controls throughout the year in comparison to broad ranging tree species. An analysis of the relationship between stem hydraulic supply and leaf functional traits suggests that stem hydraulic supply constrains leaf biomass allocation patterns among miombo tree species. Mesic specialists tend to invest more in leaf longevity than broad ranging tree species. This thesis has uncovered some interesting relationships between plant-water-relations and the distribution of miombo woodlands tree species. These results lead to the conclusion that in an event of increased ecosystem drying under future climate trends, tree species with mesic specialisation are at a greater risk of experiencing cavitation related species mortality than broad ranging ones.
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Tsuyama, Taku. "Lignification Mechanism Involved in Coniferin Transport in Differentiating Xylem of Poplar and Japanese Cypress." Kyoto University, 2015. http://hdl.handle.net/2433/199360.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第19036号
農博第2114号
新制||農||1031(附属図書館)
学位論文||H27||N4918(農学部図書室)
31987
京都大学大学院農学研究科森林科学専攻
(主査)教授 髙部 圭司, 教授 髙野 俊幸, 教授 矢﨑 一史
学位規則第4条第1項該当
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Costa, Ricardo Alexandre Rodrigues. "Chemical composition of cork, phloem and xylem of Quercus suber L. from different provenances." Master's thesis, ISA/UL, 2019. http://hdl.handle.net/10400.5/18375.
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Mestrado em Engenharia Florestal e dos recursos Naturais - Instituto Superior de Agronomia / ULA composição química de cortiça, floema e xilema foi determinada em árvores jovens de Quercus suber L. de três proveniências (Alcácer do Sal, Azeitão e Santiago do Cacém) de uma importante região de produção suberícola em Portugal, tendo em vista a análise de eventuais diferenças entre proveniências. Foram estudadas três árvores por proveniência, determinando-se o conteúdo em cinzas, extractivos (solubilizados em diclorometano, etanol e água), suberina (no caso da cortiça), lenhina e polissacáridos. Os três tecidos mostraram grandes diferenças na sua composição química. A composição química média da cortiça foi a seguinte: 0,66 % em cinzas, 11,7 % extractivos, 42,3 % suberina, 24,1 % lenhina e 16,2 % polissacáridos; do floema 2,9 % cinzas, 4,5 % extractivos, 38,0% lenhina e 49,1 % polissacáridos; e do xilema 1,1 % cinzas, 5,6 % extractivos, 23,4 % lenhina e 64,6 % polissacáridos. A análise estatística mostrou que a proveniência apenas foi um factor de variação significativo para os extractivos em etanol no caso da cortiça e os polissacáridos no floema. A composição monomérica da lenhina de todas as amostras foi analisada por pirólise analítica a 650 ºC. A lenhina dos três tecidos difere substancialmente: o rácio S/G foi 0,12 na cortiça, 1,1 no floema e 2,3 no xilema. Os compostos obtidos por pirólise foram também identificados e, sempre que foi possível determinar a sua origem, agrupados em açúcares, lenhina e suberina (apenas nas amostras de cortiça). Os açúcares representaram 58,6 %, 63,1 % e 25,4 %, a lenhina 14,4 %, 10,4 % e 12,6 % respectivamente no floema, xilema e cortiça, e a suberina na cortiça representou 33,0 % do total dos picos dos pirogramas
N/A
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Crews, Laura Jean Elizabeth. "Wound-induced xylem mucilage in Zea mays L. roots traps invaders and keeps vessels functional." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq36923.pdf.
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Cirelli, Damian. "Anatomy and Physiology of Sugar Maple (Acer saccharum March.) in Relation to Xylem Sap Pressure." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/CirelliD2005.pdf.
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Escamez, Sacha. "Xylem cells cooperate in the control of lignification and cell death during plant vascular development." Doctoral thesis, Umeå universitet, Institutionen för fysiologisk botanik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-115787.
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The evolutionary success of land plants was fostered by the acquisition of the xylem vascular tissue which conducts water and minerals upwards from the roots. The xylem tissue of flowering plants is composed of three main types of cells: the sap-conducting tracheary elements (TE), the fibres which provide mechanical support and the parenchyma cells which provide metabolic support to the tissue. Both the TEs and the fibres deposit thick polysaccharidic secondary cell walls (SCWs), reinforced by a rigid phenolic polymer called lignin. The cell walls of TEs form efficient water conducting hollow tubes after the TEs have undergone programmed cell death (PCD) and complete protoplast degradation as a part of their differentiation. The work presented in this thesis studied the regulation of TE PCD by characterizing the function of the candidate PCD regulator METACASPASE 9 (MC9) in Arabidopsis thaliana xylogenic cell suspensions. These cell suspensions can be externally induced to differentiate into a mix of TEs and parenchymatic non-TE cells, thus representing an ideal system to study the cellular processes of TE PCD. In this system, TEs with reduced expression of MC9 were shown to have increased levels of autophagy and to trigger the ectopic death of the non-TE cells. The viability of the non-TE cells could be restored by down-regulating autophagy specifically in the TEs with reduced MC9 expression. Therefore, this work showed that MC9 must tightly regulate the level of autophagy during TE PCD in order to prevent the TEs from becoming harmful to the non-TEs. Hence, this work demonstrated the existence of a cellular cooperation between the TEs and the surrounding parenchymatic cells during TE PCD. The potential cooperation between the TEs and the neighbouring parenchyma during the biosynthesis of lignin was also investigated. The cupin domain containing protein PIRIN2 was found to regulate TE lignification in a non-cell autonomous manner in Arabidopsis thaliana. More precisely, PIRIN2 was shown to function as an antagonist of positive transcriptional regulators of lignin biosynthetic genes in xylem parenchyma cells. Part of the transcriptional regulation by PIRIN2 involves chromatin modifications, which represent a new type of regulation of lignin biosynthesis. Because xylem constitutes the wood in tree species, this newly discovered regulation of non-cell autonomous lignification represents a potential target to modify lignin biosynthesis in order to overcome the recalcitrance of the woody biomass for the production of biofuels.
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Luz, Ana Luísa de Oliveira Moreira da. "Análise da formação dos anéis de crescimento anual das árvores ao longo dum ciclo de actividade cambial." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4028.
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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de AgronomiaThe growing awareness concerning the influence of environmental factors on tree´s growth, particularly under the threat of climate changes, fostered the design of a new method to study cambial activity and xylogenesis along the growing season, under the influence of Mediterranean climate. Unlike the currently used methods, that extract samples from the stem, this method is based on the collection of twigs from the crown, with the purpose of overcoming the disadvantages associated to other methods, such as the impact on tree, the associated cost, the lack of simplicity and of applicability to softwood and hardwood species. The study includes ten hardwood and softwood species. After microtome sectioning and staining (safranin and astrablue) techniques, the sections were photographed and analyzed, aiming at monitoring the ring development and defining the period of cambial activity. The twigs revealed great differences in the radial growth, that might be associated to their particular position in the tree (proximity of leaves, source of photoassimilates) and/or to the effect of the different microclimates created in the crown. The method showed effectiveness in the study of cambial activity, revealing, however, limitations on the study of ring development, due to the impossibility to compare samples.
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Siebrecht, Sylke. "Untersuchungen zur Dynamik des Nährstofftransports im Xylem von Pappeln unter besonderer Berücksichtigung der Stickstoffversorgung des Sprosses." [S.l.] : [s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=962906662.
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Gebauer, Tobias. "Water turnover in species-rich and species-poor deciduous forests xylem sap flow and canopy transpiration /." Göttingen : Georg-August-Universität, 2010. http://webdoc.sub.gwdg.de/diss/2010/gebauer/gebauer.pdf.
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Nilsson, Hampus, and Sebastian Olsson. "Jämförande studie gällande materialplaneringsprocessen vid verkstäderna OPS och OPX. : – En fallstudie på Xylem Inc. i Emmaboda." Thesis, Linnéuniversitetet, Institutionen för ekonomistyrning och logistik (ELO), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-35989.
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Bakgrund: I dagsläget upplever verkstadschefen vid OPS att materialplaneringsprocessen skulle kunna effektiviseras. I dagsläget är det oklart hur processen utförs och vad logistikerna lägger ner tid på i varje aktivitet. Genom en kartläggning och jämförelse med en annan verkstad vid Xylem Inc. i Emmaboda finns möjligheten till att se på vilket sätt andra verkstäder arbetar med materialplaneringsprocessen. Syfte: Att identifiera nuläget genom att beskriva och kartlägga materialplaneringsprocessen vid de två verkstäderna OPS och OPX för att identifiera var det förekommer skillnader mellan de två verkstäderna och vad som orsakar onödig tidsåtgång. Syftet är också att utifrån jämförelsen ge förbättringsförslag för att tidseffektivisera materialplaneringsprocessen vid verkstaden OPS. Metod: Studien är en kvalitativ fallstudie på verkstäderna OPS och OPX på Xylem Inc. i Emmaboda där datainsamlingen skett genom semi-strukturerade intervjuer och direkta observationer. Först genomfördes processkartläggning av materialplaneringsprocessen vid de två verkstäderna tillsammans med tidtagning av delprocessernas tidsåtgång. Utifrån detta kunde sedan en jämförelse mellan de två verkstäderna utföras. Efterföljande kapitel i studien fokuserar på vad verkstaden OPS kan göra för att tidseffektivisera materialplaneringsprocessen. Slutsatser: Det förekommer skillnader mellan de två verkstädernas arbetssätt på endast en av delprocesserna men det är väsentlig skillnad i tidsåtgång på samtliga delprocesser. Tidsåtgången kan härledas från otillräcklig kapacitet i verkstaden OPS och genom olika förslag på frigörelse av kapacitet samt uppdaterade och anpassade system kan verkstaden OPS tidseffektivisera materialplaneringsprocessen.Background: In today´s situation the workshop manager feel that the material planning process at workshop OPS can be more efficient. The reason for this is that in the current situation, it is unclear how the process is carried out and what the logistics are put in time in every activity. Through a survey and comparison with another workshop at Xylem Inc. in Emmaboda it is possible to see how the workshops makes them different and what causes the time required for the material planning process. Purpose: To identify the current situation be describing and mapping materials planning process at the two workshops OPS and OPX to identify where there are differences between the two workshops and what causes unnecessary delays. It also aims based on the comparison suggest measures to streamline the time material planning at the workshop OPS. Method: The study is a qualitative case study of the workshops OPS and OPX at Xylem Inc. in Emmaboda where data collection occurred through semi-structured interviews and direct observations. First conducted process mapping of materials planning process at the two workshops together with the timing of the time spent on each sub-process. Based on this, a comparison could be made of the two workshops. The remaining chapter of the study focuses on what the workshop OPS can do to be more time-efficient on their material planning process. Conclusion: There are differences between the two workshops working on only one of the sub-processes but there is considerable difference in the time needed in every part of the process. The duration can be derived from insufficient capacity in the workshop OPS and through various suggestions for the emancipation of capacity as well as updated and adapted systems can workshop OPS time-efficiency materials planning process.
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Kemp, M. S. "Chemical aspects of resistance to silver leaf disease in the secondary xylem of apple and pear." Thesis, University of Bristol, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379346.
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