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1

Knapp, Darin J. "A phenomenological exploration of relationship effort in emerging adult cyclical dating relationships." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32567.

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Doctor of Philosophy
Family Studies and Human Services
Jared R. Anderson
Cyclical romantic relationships—those characterized by breaking up and getting back together or having on/off periods—are a frequent phenomenon in the emerging adult population. These dating relationships maintain some distinctions from other more stable relationships, including the ways that partners strive to sustain relationship health. The purpose of this phenomenological qualitative inquiry was to increase in-depth understanding of how emerging adult dating partners’ relationship effort affects relationship transitions within cyclical dating relationships. Ten heterosexual emerging adult couples (10 men, 10 women) currently in cyclical dating relationships were interviewed about their experiences with relationship effort and maintenance. Participant interviews were analyzed according to the Interpretative Phenomenological Analysis (IPA) method. Specific themes emerged from the data, focusing on how perceived individual effort in the relationship, perceived partner effort in the relationship, and specific maintenance behaviors couples used to sustain relational health affected couple decisions about relationship transitioning. Implications regarding relationship education and clinical intervention among cyclical emerging adult couples are discussed. Future research could focus on continued expansion of understanding when in relationship history cyclical patterns begin, and how partners navigate transitions when both perceive reduced relationship effort.
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Washburn-Busk, Michelle. "An exploratory study of change mechanisms for ambivalence reduction in young adult cyclical relationships." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/38264.

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Master of Science
School of Family Studies and Human Services
Amber V. Vennum
Cyclical relationships (where multiple break-ups and renewals have occurred) have been characterized as being in a state of “stable instability” (Vennum & Johnson, 2015), and emerging adulthood has been deemed a critical phase of relational development and learning, as well as a time marked by instability (Arnett 2000; 2007). While the research continues to expand on what we know about the concurrent and enduring risks for distress associated with relationship cycling, little is known about what change mechanisms/interventions may reduce these risks, or how helping professionals (therapists, relationship educators) can specifically assist young adults in cyclical relationships. After conducting five focus groups, researchers found specific factors that promote or detract from “decision-making resiliency”, or DMR. Specific points of intervention for professionals working with cyclical relationships to promote DMR are discussed, which included identity development, communication, power/control dynamics and intentionality. Building off of what is known about the nuances of cyclical relationships, this study aims to inform assessments and intervention(s) that would help bolster resilience and decision-making skills in cyclical couples (or couples who have slid into relationships and are, thus, at risk for cycling) in an effort to reduce further distress.
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Neubauer, R. Joseph. "The Relationship between Dominant Macrobenthos and Cyclical Hypoxia in the Lower York River." W&M ScholarWorks, 1993. https://scholarworks.wm.edu/etd/1539617659.

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4

Nishada, Jalal, and Hoshiyar Solaimani. "Sponsring : Sponsrar företagen idrottsföreningarna för relationernas skull?" Thesis, Högskolan i Borås, Institutionen Handels- och IT-högskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18218.

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Ämnet sponsring är ett stort och brett område som vuxit under senaste åren och som många företag tillämpar. Just sponsringen har i synnerhet blivit stor i och med sportevenemang och olika idrottsföreningar som bildar samarbete med företag och arbetar tillsammans. Idrotten har blivit världsledande när det kommer till uppmärksamhet och reklam på TV och nyheter och detta vet förstås företagen om och man ser en investering i att bilda sponsringssamarbete i dessa sammanhang.Som företagare kan man välja att sponsra ett stort fotbollslag som får mycket tid i media och TV och detta medverkar till att företaget också syns i en större utsträckning och får mer uppmärksamhet. Som företagare kan man också sponsra ett mindre fotbollslag som man har en relation till eller som man tycker gör ett vettigt arbete för ungdomar osv. I vår studie undersökte vi just denna typ av sponsring och vi har arbetat med två olika fotbollsföreningar som jobbar på helt olika villkor och nivåer. Vi har tittat till deras största sponsorer och har i vår studie kommit fram till om företagen sponsrar idrottsföreningar för relationernas skull?Vi har varit och studerat IF Elfsborg och Borås AIK och gjort en kvalitativ undersökning i form av personliga intervjuer med de högst uppsatta personerna inom föreningarna när det kommer till sponsring. Vi har även gjort personliga intervjuer med de två klubbarnas stora sponsorer och det är Swedbank Sjuhärad, AB Bostäder, NetonNet och V/S/B. Vi anser att de empiriska material vi har använt och fått ut av intervjuerna har varit tillräckligt för att besvara vårt syfte med denna studie och vi känner oss nöjda med det vi har lärt oss och kommit fram till.De slutsatser som vi har kommit fram till när det kommer till föreningarna vi har arbetat med är att de inte bara skiljer i storlek utan även i arbetssätt. IF Elfsborg är en av Sveriges största idrottsföreningar och det är naturligt att företagen sponsrar de för att förknippas med föreningen och stärka sitt varumärke. Där av kan man säga att det är en investeringsfråga ur företagens synvinkel vad gäller att sponsra IF Elfsborg.Borås AIK är en mindre förening än IF Elfsborg i alla avseenden och det enda man egentligen har tillsammans är att båda hör till fotbollen. Företagen ser ingen investering i att sponsra Borås AIK då klubben aldrig är på TV och väldigt sällan i tidningen. Här handlar det nästan enbart om relationsbaserad sponsring och att man vill klubben väl. Borås AIK arbetar i ett väldigt utsatt område med mycket invandring och kriminalitet och man utbildar många ungdomar på området vilket många företag tycker om och vill vara med och stötta.
Program: Dataekonomutbildningen
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5

Monk, James Kale. "Commitment and sacrifice in emerging adult cyclical and non-cyclical romantic relationships." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/15563.

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Master of Science
Department of Family Studies and Human Services
Amber V. Vennum
Patterns in, and quality of, early romantic relationships have been found to impact future relationship outcomes (Donnellan et al., 2005; Overbeek et al., 2007). Commitment and satisfaction with sacrifice have been cited as important constructs in relationship health and stability as they indicate investment in the relationship (Stanley & Markman, 1992; Rusbult, 1983). Little research has been done on the bi-directional relationship of these two constructs. Many authors indicate that commitment predicts sacrifice (e.g. Van Lange, Rusbult, et al., 1997), but others argue that sacrifice predicts subsequent commitment (e.g. Kelley, 1979). The purpose of this study was to explore the time-ordering of these constructs and whether a history of relationship breakup and renewal (termed cyclicality) moderated this relationship in an emerging adult population (n = 246). Using a cross-lagged model over three time points, the present study found support for a bi-directional relationship between commitment and satisfaction with sacrifice that was not moderated by a history of cyclicality. However, partners with a history of breakup and renewal did report lower dedication at Time 3, indicated by a group mean difference. Implications for theory, research, and intervention are discussed.
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6

Simonsen, Shane M. "Diversity and structure-activity relationships of the cyclotides /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19079.pdf.

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7

Rezai, Taha. "Structural permeability relationships of cyclic peptides /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2007. http://uclibs.org/PID/11984.

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8

Drago, Valeria <1977&gt. "Cyclic alternating pattern in sleep and its relationship to creativity." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/4036/.

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Background/Objectives: Sleep has been shown to enhance creativity, but the reason for this enhancement is not entirely known. There are several different physiological states associated with sleep. In addition to rapid (REM) and non-rapid eye movement (NREM) sleep, NREM sleep can be broken down into Stages (1-4) that are characterized by the degree of EEG slow wave activity. In addition, during NREM sleep there are transient but cyclic alternating patterns (CAP) of EEG activity and these CAPs can also be divided into three subtypes (A1-A3) according to speed of the EEG waves. Differences in CAP ratios have been previously linked to cognitive performances. The purpose of this study was to learn the relationship CAP activity during sleep and creativity. Methods: The participants were 8 healthy young adults (4 women), who underwent 3 consecutive nights of polysomnographic recording and took the Abbreviated Torrance Test for Adults (ATTA) on the 2 and 3rd mornings after the recordings. Results: There were positive correlations between Stage 1 of NREM sleep and some measures of creativity such as fluency (R= .797; p=.029) and flexibility ( R=.43; p=.002), between Stage 4 of Non-REM sleep and originality (R= .779; p=.034) and a global measure of figural creativity (R= .758; p=.040). There was also a negative correlation between REM sleep and originality (R= -.827; p= .042) . During NREM sleep the CAP rate, which in young people is primarily the A1 subtype, also correlated with originality (R= .765; p =.038). Conclusions: NREM sleep is associated with low levels of cortical arousal and low cortical arousal may enhance the ability of people to access to the remote associations that are critical for creative innovations. In addition, A1 CAP activity reflects frontal activity and the frontal lobes are important for divergent thinking, also a critical aspect of creativity.
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9

Sriraman, R. "Cyclic guanosine 3', 5' - cyclic monophosphate (cGMP) enhancement & its relationship to vascular function & insulin sensitivity." Thesis, Exeter and Plymouth Peninsula Medical School, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.701082.

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10

MacDonell, Karen Loraine. "Relationship between cyclic AMP-dependent protein kinase activation and smooth muscle relaxation by cyclic AMP and analogs." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30098.

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It is generally held that adenosine 3',5'-cyclic monophosphate (cAMP) mediates smooth muscle relaxation by the activation of cAMP-dependent protein kinase (PKA). This hypothesis was tested in two intact smooth muscle preparations, the rat vas deferens and the bovine coronary artery, using exogenously applied cAMP and cAMP analogs. After 30 minutes of incubation, N⁶,2'-0-dibutyryl-cAMP (dBu-cAMP) (1 - 100 μM) inhibited phenylephrine (PE)-induced tension generation in the rat vas deferens in a dose-dependent manner. This analog (10 μM) also activated the soluble fraction of PKA but did not activate the particulate fraction kinase. In contrast, 8-bromo-cAMP (8Br-cAMP) (10 -100 μM) did not have any significant effect on inhibition of PE-induced tension after 30 minutes of incubation but, at a concentration of 10 μM, significantly activated both the soluble and particulate fractions of PKA. The time course of activation of soluble PKA activation by 8Br-cAMP (10 μM) demonstrated that the kinase was significantly activated only after 30 minutes of exposure to the analog. In the bovine coronary artery, cAMP (10 - 100 μM) relaxed potassium-depolarized helical strips and significantly activated soluble PKA in a dose-dependent manner. dBu-cAMP (10 - 100 μM) affected neither tension nor soluble PKA activity. 8Br-cAMP (10 - 100 μM) did not affect the coronary artery tension but did activate soluble PKA. Both smooth muscle preparations were homogenized with charcoal prior to the determination of PKA activity in order to minimize artifactual assay results. As a further precaution, extracellularly associated cAMP and analogs were also washed from bovine coronary artery strips after the incubation period. These controls allowed for a valid assessment of PKA activity in the cyclic nucleotide-treated tissues. The results of the tension and kinase studies demonstrate a lack of correlation between activation of PKA and inhibition of rat vas deferens contraction or relaxation of bovine coronary artery. This does not support the hypothesis that the kinase is responsible for cAMP-induced relaxation of vascular and non-vascular smooth muscle. While the mechanism by which exogenous cAMP and specific analogs induce relaxation in some smooth muscle preparations remains unclear, it can be suggested that PKA activation is not necessarily required for the final functional effect.
Medicine, Faculty of
Anesthesiology, Pharmacology and Therapeutics, Department of
Graduate
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11

Ashamu, Gloria Abiodun. "Synthesis and structure-activity relationships of cyclic adenosine 5'-diphosphate ribose analogues." Thesis, University of Bath, 1998. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389951.

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12

Spathelf, Barbara Marianne. "Qualitative structure-activity relationships of the major tyrocidines, cyclic decapeptides from Bacillus aneurinolyticus." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4001.

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Thesis (PhD (Biochemistry))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: The need for alternative or supplementary treatments due to the global problem of microbial resistance towards conventional antimicrobials may be met by the development of novel drugs based on antimicrobial peptides. The antimicrobial peptides of interest to this study were the tyrocidines, cyclic decapeptides produced by Bacillus aneurinolyticus. Although these antimicrobial peptides were the first natural antibiotic to be discovered though a systematic search for antibacterial compounds, information regarding their bioactivity, structure-activity relationships, determinants of bioactivity and mode of action is limited. The aim of this study was to investigate the antibacterial and antiplasmodial activity, as well as to identify determinants of bioactivity modulation, of the natural tyrocidine library. The study indicated that the tyrocidines exhibit significant activity toward Gram-positive bacteria, notably Listeria monocytogenes, and the intraerythocytic parasite, Plasmodium falciparum. Both the antilisterial and antiplasmodial activity was found to be highly dependent on peptide identity and self-assembly. The antilisterial activity of the tyrocidines was shown to be associated with increased self-assembly within a membrane-like environment, which suggested that formation of lytic complexes within the bacterial membrane may play a crucial role in tyrocidine activity. In contrast to the observations for antilisterial activity, the antiplasmodial activity of the tyrocidines was shown to be associated with reduced self-assembly within a membrane-like environment, which suggested that the antiplasmodial activity of the tyrocidines is mediated by a mechanism other than the formation of lytic complexes within the target cell membrane. In addition to the influence of peptide identity and self-assembly, the bioactivity of the tyrocidines was found to be highly sensitive to environmental conditions, notably the presence of calcium. The antilisterial activity, as well as the mode of action, of the tyrocidines was also found to be highly sensitive to tyrocidine-Ca2+ complexation and the concomitant induction of higher-order structures. Tyrocidine-Ca2+ complexation was shown to greatly enhance antilisterial activity and change the mechanism of action from a predominantly membranolytic to an alternative, non-lytic mode of action. The results of this investigation suggest that the alternative mode of tyrocidine activity may be related to complexation with Ca2+. It is hypothesised that such complexation may either (1) promote tyrocidine-DNA complexation, and thus inhibition of transcription and/or replication; or (2) interfere with Ca2+ homeostasis, and thus influence vital cell functions. Overall, it may be hypothesised that tyrocidine activity and mode of action is modulated by a critical play-off between self-assembly, cation-complexation and membrane-interaction. As these modulators of activity are highly dependent on tyrocidine sequence/structure, the wide variety of tyrocidines found in the natural complex may allow for optimal interaction with and activity toward a variety of microbes.
AFRIKAANSE OPSOMMING: Die universele probleem van mikrobiese weerstand teen konvensionele antimikrobiese middels en die wêreld-wye noodsaaklikheid vir alternatiewe of bykomende behandeling mag deur die ontwikkeling van nuwe middels, gebasseer op antimikrobiese peptiede, vervul word. Die antimikrobiese peptiede van belang tot hierdie studie is die tirosidiene, sikliese dekapeptiede wat deur Bacillus aneurinolyticus geproduseer word. Informasie ten opsigte van die tirosidiene se bioaktiwiteit, struktuur-funksieverwantskap, determinante van bio-aktiwiteit en meganisme van aksie was beperk, alhoewel hierdie peptiede die eerste antimikrobiese peptiede was wat ontdek is deur ‘n sistematiese soektog vir antimikrobiese middels. Die doelwit van hierdie studie was die ondersoek van antibakteriële and antiplasmodiese aktiwiteit, sowel as om die determinante van bio-aktiwiteit modulering van die natuurlike tirosidienbiblioteek te ondersoek. Hierdie studie het getoon dat die tirosidiene merkwaardige aktiwiteit teenoor Gram-positiewe bakterië, in besonder Listeria monocytogenes het, asook teenoor die intra-eritrositiese parasiet, Plasmodium falciparum. Daar is bevind dat beide die antilisteriese en antiplasmodiese aktiwiteite hoogs afhanklik is van peptiedidentiteit en self-verpakking. Daar is gewys dat die antilisteriese aktiwiteit van die tirosidiene geassosieer is met verhoogde self-verpakking in ’n membraanagtige omgewing, wat ’n aanduiding is dat die vorming van litiese komplekse in die bakteriële membraan ’n kritiese rol in tirosidienaktiwiteit speel. Kontrasterend tot die waarnemings van antilisteriese aktiwiteit, is getoon dat die antiplasmodiese aktiwiteit van die tirosidiene geassosieer is met verlaagde self-verpakking in ’n membraanagtige omgewing. Dis ’n aanduiding dat die antiplasmodiese aktiwiteit van die tirosidiene gemediëer word deur ‘n ander meganisme en nie die vorming van litiese komplekse in die teikenselmembraan nie. Bykomend tot die invloed van peptiedidentiteit en self-verpakking, is daar bevind dat die bioaktiwiteit van die tirosidiene hoogs sensitief is vir die omgewing, in besonder die teenwoordigheid van kalsium. Daar is ook bevind dat die antilisteriese aktiwiteit, sowel as die meganisme van aksie, van tirosidiene hoogs sensitief is vir tirosidien-Ca2+ kompleksvorming en die gevolglike induksie van of hoër-orde strukture. Daar is gewys dat tirosidien-Ca2+ kompleksvorming die antilisteriese aktiwiteit drasties verhoog en dat die meganisme van aksie verander van ’n oorwegende membranolitiese meganisme na ’n alternatiewe nie-litiese meganisme van aksie. Die resultate van hierdie ondersoek het aangedui dat die alternatiewe meganisme van aksie van tirosidienaktiwiteit moontlik verband kan hou met kompleksvorming met Ca2+. Die hipotese is dat sodanige kompleksvorming moontlik of (1) tirosidien-DNA komplekvorming aanmoedig, en dus transkripsie en/of replikasie inhibibeer of (2) met Ca2+ homeostase inmeng, en sodoende lewensnoodsaaklike selfunksies beïnvloed. Die algemene hipotese is dat tirosidienaktiwiteit en meganisme van aksie deur ’n kritiese spel tussen self-verpakking, katioonkompleksvorming en membraaninteraksie gemoduleer word. Die wye verskeidenheid van tirosidiene, wat in die natuurlike kompleks gevind word, kan moontlik toelaat vir die optimale interaksie met, en aktiwiteit teenoor ’n verskeidenheid van mikrobes, aangesien die aktiwiteitmoduleerders hoogs afhanklik is van tirosidien struktuur/volgorde.
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Mondschein, Ryan Joseph. "Structure-Property Relationships of Polyester Regioisomers and Pendant Functionalized Polyetherimides." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/101706.

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Step-growth polymerization enabled the synthesis of novel polyester regioisomers and pendant functionalized polyetherimides (PEI)s. Novel monomers incorporated at targeted mol % produced series of polyesters and PEIs, suitable for systematic analysis of key polymer properties. Subsequent compositional, thermal, mechanical, and rheological characterization forged structure-property relationships to further understand the influence of composition on performance. Altering regiochemistry is a subtle way to maintain the same polymer composition but tune desired properties. Similarly, introducing functional pendant groups expands the property profile of common industrial polymers and installs a handle for secondary chemistry after synthesizing the main polymer. Both altering regiochemistry and adding pendant groups alters polymer properties without the need for large changes in synthetic requirements or reaction conditions, ideal for industrial adoption. Incorporation of a kinked bibenzoate (BB)-based diester monomers into the commonly utilized linear regioisomer afforded processable amorphous and semi-aromatic (co)polyesters. BB-(co)polyesters with ethylene glycol (EG) possessed improved barrier performance compared to poly(ethylene terephthalate) (PET) while improving on mechanical properties, including tensile and flexural modulus/strength, rivaling bisphenol-A polycarbonate (BPA-PC). Replacement of EG with 1,4-cyclohexanedimethanol (CHDM) improved thermal properties closer to BPA-PC, while enabling melt rheological analysis due to its amorphous morphology. Time-temperature superposition (TTS) analysis produced master curves provided insight into the entanglement molecular weight (Me) and entanglement density. More kinked structures possessed a lower Me and more entanglements. Introducing kinked monomers posed the question of cyclic speices generation during polymerization, common in step-growth reactions. Thus, systematic incorporation of meta-substituted hydroxyethylresorcinol and para-substituted hydroxyethylhydroquinone regioisomers into PET analogues enabled the characterization of cyclic formation due to monomer regioisomers. Increased meta substitution produced increased amounts of cylic species, analyzed by size exclusion chromatography (SEC). Adding functionality to high performance polyetherimides (PEI)s is difficult due to the high temperatures required for processing. The lack of thermal stability for commonly utilized H-bonding/reactive groups limits viable moieties. Utilizing the high temperture processing, PEIs incorporating pendant carboxylic acids reacted in the melt to form branched PEIs. These branched PEIs exhibited steeper shear thinning as well as improved flame resistance, limited in thin film commercial PEIs.
Doctor of Philosophy
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Díaz, i. Cirac Anna. "Mechanism of action of cyclic antimicrobial peptides." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/38252.

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This PhD thesis is the result of the combination of experimental and computational techniques with the aim of understanding the mechanism of action of de novo cyclic decapeptides with high antimicrobial activity. By experimental techniques the influence of the replacement of the phenylalanine for tryptophan residue in their antimicrobial activity was tested and the stability in human serum was also analyzed, in order to evaluate their potential therapeutic application as antitumor agents. On the other hand, the interaction amongst the peptide BPC194 c(KKLKKFKKLQ), the best candidate from the whole library of cyclic peptides, and a model anionic membrane was simulated. The results showed a structure-function relationship derived from the stable conformation of the peptides involved in the membrane permeabilization. As a result, a rational design was performed being BPC490 the peptide with best antimicrobial activity compared with the best active peptide from the original library.
Aquesta tesi doctoral resulta de la combinació d’estudis mitjançant tècniques experimentals i computacionals amb l’objectiu d’entendre el mecanisme d’acció de "de novo" decapèptids cíclics amb elevada activitat antimicrobiana. Experimentalment, es va avaluar la influència de la substitució dels residus de fenilalanina per triptòfan en la seva activitat antimicrobiana i també la seva estabilitat sèrum humà, per tal de valorar la seva possible aplicació terapèutica envers el càncer. Per altra banda, es va simular la interacció del pèptid BPC194 c(KKLKKFKKLQ), millor candidat de la biblioteca de pèptids cíclics, amb models aniònics de bicapa lipídica. Els resultats van posar en manifest una relació estructura-funció derivada de la conformació estable dels pèptids que participen directament en la permeabilització de la membrana. Es va procedir doncs al disseny racional de nous pèptids cíclics sent el pèptid BPC490 el que va presentar una millor activitat bacteriana en comparació amb el pèptid més actiu de la llibreria original.
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Kazmierski, Wieslaw Mieczyslaw. "Synthesis and hydrogen-1 NMR conformational analysis of potent and mu opioid receptor selective cyclic peptides: Topographical design utilizing a conformationally stable template." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184454.

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There is a dogma in molecular biology that biological functions of peptides are determined by their structure ("function" code), coded in their primary structure ("structure" code). This work describes a new approach that attempts to elucidate these relationships by peptide topology design based on intriguing conformational properties of pipecolic acid based amino acids--like 1,2,3,4 tetrahydroisoquinoline (Tic). Opioid peptides, owing to the heterogeneity of opioid receptors, display a wide variety of physiological actions. The mu opioid receptor selective octapeptide I (D-Tic-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH₂) is a model compound for topographical modifications induced by sequential substitutions by Tic residue. Thus, the closely related peptides I and II (Gly-D-Tic-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH₂, obtained by coupling Gly residue to I) have contrasting affinities for the mu opioid receptor (IC₅₀ = 1.2 and 278 nM, respectively). Conformational analysis of I and II by means of 1D and 2D ¹H NMR spectroscopy allowed to determine dramatic differences in the side chain orientation of D-Tic in both peptides and to propose features of the bioactive conformation. The extended conformation of I (due to g(-) side chain conformation of D-Tic) is well recognized by the mu receptor in contrast to the folded conformation of II (due to a g(+) side chain conformation of D-Tic¹, that places the aromatic ring on the opposite side of the molecule), which is not. Peptide III (D-Phe-Cys-Tic-D-Trp-Orn-Thr-Pen-Thr-NH₂), featuring replacement of Tyr³ by Tic³, binds very weakly to the mu opioid receptor, due to rotation of the Tic aromatic side chain to the opposite side of the molecule (Tic side chain is in a g(+) conformation again). As these substitutions conserve the conformation of the backbone, constrained cyclic amino acids (picolic acid derivatives) can modify the topography of the peptide in a predictable manner, and (in conjunction with biological data) disclose structural elements of bioactive conformations. The mechanisms of pipecolic acid side chain rotamer selection, will be discussed in the context of design principles.
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Ko, Hunebum. "Modeling and application of bond stress-slip relationship between FRP sheet and concrete under cyclic load." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136347.

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Mora, Pons Isabel. "Antimicrobial activity in Bacillus spp. from plant environments against plant pathogens. Relationship with cyclic lipopeptide genes and products." Doctoral thesis, Universitat de Girona, 2013. http://hdl.handle.net/10803/128416.

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Bacillus subtilis and related species have strong interest in agriculture because several strains are biocontrol agents of plant diseases, which have been recognized as biosafe. In this work, a selective enrichment procedure based on PCR targeting antimicrobial peptide (AMP) genes has been designed and evaluated to screen field samples and pure cultures of Bacillus spp. The procedure increased the yield of isolation of Bacillus strains compared to the standard procedure. The isolates were characterized according to the presence of six AMP genes, the capacity to produce AMPs, and their antimicrobial activity against fungal and bacterial plant pathogens. The relationships between AMP genes, products and antimicrobial activity have been established. Finally, a collection of 184 Bacillus has been obtained having multiple AMP genes simultaneously, and producing several cyclic lipopeptides, with a wide range of antimicrobial activity. It is expected that such strains would be suitable candidates to develop novel biopesticides for plant disease control
Bacillus subtilis i les espècies relacionades són de gran interès per l'agricultura, gràcies a la seva implicació en el biocontrol de malalties de plantes, i ser reconeguts com a biosegurs. En aquest treball s'ha dissenyat i avaluat un procés d'enriquiment selectiu basat en la detecció de gens relacionats amb la síntesis de pèptids antimicrobians, per tal d'analitzar mostres naturals i cultius purs de Bacillus. El procediment va permetre un increment d'aïllament de Bacillus en comparació al mètode estàndard d'aïllament. Els aïllats van ser caracteritzats segons la presencia de sis gens biosintètics, la capacitat de produir ciclolipopèptids i la seva activitat antimicrobiana contra fongs i bacteris patògens de plantes. Es van establir les relacions existents entre la presència del gens biosintètics, els productes i l'activitat antimicrobiana. Finalment, es va obtenir una col•lecció de 184 aïllats de Bacillus amb múltiple presència de gens biosintètics de pèptids antimicrobians simultàniament, productors de varis ciclolipopèptids, i amb un ampli espectre d'activitat antimicrobiana. És d'esperar que aquests aïllats resultin bons candidats per desenvolupar nous biopesticides per al control de malalties de plantes
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18

Dobie, Karen Louise. "Investigating the relationship between abnormal prion protein (PrPSc) and the transmissible spongiform encephalopathy (TSE) infectious agent." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8107.

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Transmissible spongiform encephalopathies (TSEs) are a group of fatal, neurodegenerative diseases that can affect both humans and animals. TSEs can be sporadic, familial, or acquired diseases. The prion hypothesis states that a misfolded form of the host glycoprotein, PrPC, acts as the infectious agent in TSE disease. The misfolded form, PrPSc, is increased in β-sheet content, detergent insoluble and partially resistant to proteinase K (PK) digestion. Based on the prion hypothesis, most current post-mortem diagnostic tests rely on the presence of PrPSc as indicative of TSE disease. However, recently experimental cases of TSE disease have been identified where no PrPSc deposition is evident. One example of this is a murine transgenic model of Gerstmann Sträussler Scheinker (GSS) disease. GSS is a familial TSE disease, caused by a number of different mutations in human PrP including a point mutation from proline to leucine at residue 102. A murine model of GSS disease, produced through gene-targeting, contains the same point mutation at the equivalent residue, 101, in murine PrP. These mice do not develop spontaneous disease during their lifespan, but when inoculated intra-cerebrally with either human P102L GSS (101LL/GSS) or hamster 263K scrapie (101LL/263K); develop a clinical disease and vacuolar TSE-related pathology. Upon biochemical and immunohistochemical analysis, the brain tissues of these clinically ill mice contain little or no detectable PrPSc. However titration experiments have previously shown infectivity titres of 107-109IU/g of brain tissue. Standard PK digestion (at 37°C), NaPTA precipitation and isolation of PrPSc through detergent insolubility and differential centrifugation all confirmed the observation of little or no detectable PK-resistant PrP (PrP-res) in the 101LL/GSS and 101LL/263K brain tissues, despite the high levels of TSE infectivity. The presence of PrPSc and/or TSE infectivity in the spleen during disease pathogenesis is dependent upon TSE agent strain and host species. Previous studies utilising wild-type mice infected with ME7, have shown that the levels of infectivity observed in spleen tissue are 2- 3log10 lower than those observed in the brain tissue of the same mice. However, experiments conducted as part of this thesis showed that sub-passage of both the brain and spleen tissue from clinically ill 101LL/GSS and 101LL/263K mice into 101LL mice by intra-cerebral inoculation result in short incubation periods, indicating that infectivity levels were similarly high in both tissues. Biochemical analysis of the primary spleen tissue identified the presence of PrP-res, albeit at lower levels than those observed in wild-type spleens infected with a standard laboratory TSE strain, ME7 or 79A. However, the presence of PrP-res indicates that the spleen has a role in disease pathogenesis, which will require further investigation. Additionally, the spleen tissue maintains the discrepancy between PrP-res and TSE infectivity that is observed in the brain tissue of these models and further questions the prion hypothesis. As little or no PrP-res was detectable in the brain tissues of 101LL/GSS and 101LL/263K mice by standard biochemical and immunohistochemical techniques, it was hypothesised that an in vitro amplification technique, protein misfolding cyclic amplification (PMCA) could amplify PrPSc to detectable levels. A series of optimisation experiments were performed to produce a reliable positive control for amplification of mouse PrPSc from a standard laboratory mouse TSE strain, 79A or ME7, with a normal wild-type mouse brain homogenate substrate. While a wide range of technical and experimental conditions were investigated, consistent and reproducible amplification of mouse PrPSc was not achieved and therefore amplification of PrPSc from 101LL/GSS and 101LL/263K tissues could not be performed as interpretation of results would be complicated without the presence of a positive control. Previous research has shown that while other commercial assays, e.g. TeSeE (BioRad), identified tissues from these models as borderline positive or negative for TSE disease, one TSE diagnostic assay, the IDEXX HerdChek kit, that utilises the Seprion ligand, identified both the brain and spleen tissue from 101LL/GSS and 101LL/263K clinical mice as positive for TSE disease. In order to identify if TSE infectivity is associated with the target of the Seprion ligand, brain tissue homogenates from 101LL/GSS, 101LL/263K and a positive control wild-type/79A homogenate were depleted of the Seprion ligand target utilising a PAD-beads kit (Microsens Biotechnologies), which incorporates the Seprion ligand as the capture agent, in combination with magnetic beads. Upon inoculation, a single depletion of the homogenates produced no significant reduction in incubation period to clinical disease in either the depleted homogenates or the wash buffers produced, in comparison to a non-depleted brain homogenate. This result indicates that a single depletion with the Seprion ligand, did not remove enough of the aggregated protein to significantly alter the level of infectivity in the depleted homogenate and that any infectious agent, which was initially bound to the Seprion ligand due to non-specific interactions, was then released during the wash steps of the procedure. Proteomic differences between all components produced during a single depletion of an infected brain homogenate, wild-type/79A, or a normal uninfected brain homogenate were assessed to potentially identify the target of the Seprion ligand. In conclusion, these murine models of TSE disease, 101LL/GSS and 101LL/263K, which contain both high infectivity levels with little or no PrP-res in the brain tissue and similar high levels of infectivity with low levels of PrP-res in the spleen, questions the accepted correlation between levels of infectivity and PrP-res or PrPSc as proposed by the prion hypothesis. It is hypothesised that either an alternative form of PrP, which has not yet been identified is the infectious agent in these disease models, or that the TSE infectious agent is a component which associates with PrPSc rather than being PrPSc itself. The eventual identification of the infectious agent present in these unusual disease models will increase our understanding of these diseases, potentially offer improved diagnostics for infectivity, and perhaps identify novel therapeutic targets.
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19

Carre, Camille. "Synthèse et caractérisation de nouveaux matériaux polyuréthanes respectueux de l'environnement et de la santé." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAE043.

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De nouveaux polyuréthanes ont été synthétisés sans isocyanate et en intégrant des synthons biosourcés afin de développer des matériaux innovants et performants pour des applications dans le domaine de l’industrie automobile et du bâtiment. À l’issue d’un état de l’art, divers synthons et différentes stratégies ont été retenus afin d’obtenir de nouvelles architectures (macro)moléculaires et conférer aux matériaux finaux les propriétés physico-chimiques recherchées. Dans un premier temps, la réaction entre un biscyclocarbonate issu d’une molécule modèle, l’acide sébacique, et des diamines dimériques ainsi que plusieurs paramètres réactionnels ont été étudiés. Cette première étude a permis de montrer l’intérêt du ratio entre les monomères ainsi que l’influence de la fonctionnalité des diamines sur les propriétés chimiques, thermiques, rhéologiques et mécaniques des matériaux polyuréthanes sans isocyanate. Cette approche a permis dans un second temps de synthétiser des matériaux pouvant être entièrement biosourcés et de comparer leurs propriétés à celles des polyuréthanes conventionnels. Les performances de certains des matériaux thermodurcissables obtenus ont confirmé l’intérêt de cette stratégie pour les applications visées. Enfin, une troisième approche a été consacrée à la synthèse de polyuréthanes sans isocyanate thermoplastiques via la synthèse de prépolymères. Les différentes études ont montré l’importance de la structure des divers synthons sur l’organisation macromoléculaire, et ainsi sur les propriétés des matériaux finaux
Novative and performant polyurethane materials without isocyanate were synthesized using biobased molecules for applications in automotive and building industries. After a state of the art, different building blocks were selected and various strategies were established to develop new (macro)molecular architectures. First, reactions between a biscyclocarbonate from a model structure and dimer diamines were studied as well as the impact of various reaction parameters. Secondly, this approach was adapted to fully biobased materials. The properties of these nonisocyanate polyurethanes were compared with those of conventional ones. The influence of the monomer structures on the final materials was also demonstrated. The performance of some thermoset materials have confirmed the importance of the chosen strategies for the desired applications. Finally, a third approach was dedicated to the synthesis of thermoplastic nonisocyanate polyurethanes via a prepolymer synthesis. The various studies have revealed the specific impact of the building block structure on the macromolecular organization, and thus on the properties of the final materials
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20

Gong, Yun. "Structure-property relationships of dyes as applied to dye-sensitized solar cells." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/275007.

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This work investigates the correlation of structural and photovoltaic properties of dyes used in dye-sensitized solar cells. Experimental methods, including ultraviolet-visible spectroscopy, fluorescence spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy are employed to study optical and electrochemical properties of dye molecules. Computational methods, including density functional theory and time-dependent density functional theory, are used to validate and predict the optical and electronic properties of dye molecules, in their isolated state and once embedded into a working electrode device environment that comprises a dye...TiO2 interface. The results chapters begin with the presentation of a series of quinodimethene dyes that are experimentally validated for their photovoltaic application, and associated computational studies reveal that an inner structural factor - a phenyl ring rotation occurring during the optical excitation process - leads to the competitive photovoltaic device performance of these dyes. Carbazole-based dyes are then systematically studied by computation, especially considering charge transfer paths and binding modes of these dyes on a titania surface. The theoretical models for the basic building block of this chemical family of dyes, known as MK-44, successfully support and explain structural discoveries from X-ray diffraction and reflectometry that impact of their function. A benzothiadiazole-based dye, RK-1, is then systematically studied by both experimental and computational methods, and the results show that the π-bridge composed of thiophene, benzothiadiazole and benzene rings leads to excellent charge separation; and the rotation of these rings during the optical excitation process may well be consistent with the fluorescence spectrum. Finally, the well-known ruthenium-based dyes are theoretically studied to determine the properties of different ligands connected to the metal core of the complex. Conformations with different NCS ligands are calculated in terms of energy and explain well the corresponding results from X-ray diffraction. Acid-base properties of carboxyl groups connected to pyridine ligands in N3 and N749 are theoretically calculated based on thermodynamics and density functional theory. Implicit and explicit models are both adopted to predict these acid dissociative constant values, which are generally in a good agreement with the reported experimental data. The thesis concludes with conclusions and a future outlook.
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21

Martin, Guillaume. "Simulation numérique multi-échelles du comportement mécanique des alliages de titane bêta-métastable Ti5553 et Ti17." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2012. http://pastel.archives-ouvertes.fr/pastel-00873129.

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Le but de ce travail de thèse est de mieux comprendre les mécanismes de déformation à température ambiante dans les alliages de titane bêta-métastable Ti17 et Ti5553. Les microstructures étudiées sont composées de grains bêta transformé, dans lesquels la phase alpha peut précipiter, selon les relations de Burgers, sous la forme de douze variants différents. Une approche multi-échelles est donc préconisée avec trois niveaux représentatifs: macroscopique, mésoscopique (ex-grains bêta), et microscopique (variants alpha et matrice bêta de chaque grain). Différents modèles à champs moyens sont adaptés pour reproduire le comportement mécanique du Ti17 et du Ti5553. Ces modèles impliquent deux transitions d'échelle, et sont basés sur l'homogénéisation des comportements locaux, avec plusieurs manières de représenter les interactions intergranulaires. Les relations entre microstructures et propriétés mécaniques sont également considérées. Les modèles les plus complexes développés dans cette étude vont permettre de simuler l'anisotropie élastique et l'écoulement visqueux de chaque variant alpha (hcp) et de chaque matrice bêta (bcc), en employant la plasticité cristalline avec des écrouissages de type cinématique et isotrope. L'identification des paramètres matériaux est faite à partir d'une vaste base de données expérimentale provenant du projet PROMITI. Pour comprendre le rôle de chaque phase dans le processus de déformation, un calcul EF a également été fait afin de reproduire l'essai de traction sur une très fine éprouvette plate. Dans cette étude, le niveau mésoscopique est explicitement représenté en reprenant fidèlement la géométrie et l'orientation cristallographique de chaque grain bêta transformé. Des comparaisons entre expérience et simulation sont faites à l'échelle macroscopique pour les courbes contrainte - déformation, ainsi qu'au niveau mésoscopique, en considérant les champs de déplacement hors-plan et les champs de déformation.
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22

Allombert, Julie. "Rôles des voies de signalisation à di-GMP cyclique chez Legionella pneumophila." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10161/document.

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Legionella pneumophila est une bactérie aquatique qui prolifère en se répliquant à l’intérieur de cellules amibiennes. Elle peut persister dans ces environnements en vivant en communauté sous forme de biofilms. L’inhalation par l’Homme d’eau contaminée, vaporisée par les réseaux d’eau chaude ou les tours aéro‐réfrigérantes, peut mener à l’infection des macrophages pulmonaires qui se traduit par une grave pneumonie appelée légionellose. Le di‐GMP cyclique (diGMPc) est impliqué, chez diverses espèces bactériennes, dans la transition entre les modes de vie mobiles et sessiles, et chez certains pathogènes, dans la régulation de la virulence. Mon travail de thèse vise à démontrer l’implication des voies de signalisation à diGMPc dans le contrôle de la virulence et de la formation de biofilms par L. pneumophila. Cette implication a été étudiée grâce à l’inactivation systématique de chacun des gènes codant les protéines du métabolisme du diGMPc chez la souche L. pneumophila Lens. Notre étude a révélé que trois de ces protéines, Lpl0780, Lpl0922 et Lpl1118, sont spécifiquement requises pour le contrôle de la virulence et, plus particulièrement, pour la survie précoce lors de l’infection de cellules‐hôtes via l’orchestration de la sécrétion de facteurs de virulence dans la cellule‐hôte. Lpl1118 participerait également à la biogénèse de la vacuole de réplication. Cinq autres de ces protéines sont impliquées dans la régulation de la formation et de l’architecture des biofilms. L’une d’elles est, plus particulièrement, requise pour la formation de biofilms en présence d’oxyde nitrique. Ces résultats contribuent à une meilleure compréhension de l’organisation complexe et spécifique des voies de signalisation à diGMPc chez L. pneumophila et pourraient permettre d’envisager une lutte plus efficace contre ce pathogène
Legionella pneumophila is a bacterium that proliferates in fresh water environments through the replication within amoebas. These bacteria can persist in these environments through biofilm formation. The inhalation of aerosolized contaminated water through hot water systems or cooling towers can induce the infection of human lungs, leading to a severe pneumonia called legionellosis. Cyclic di‐GMP (c‐di‐GMP) in involved, in various bacterial species, in the motility‐to‐sessility transition, and in some pathogens, in virulence control. My work aims to demonstrate the involvement of signaling pathways that use c‐di‐GMP in virulence control and biofilm formation of L. pneumophila. This involvement was investigated by systematically inactivating each gene encoding a c‐di‐GMP‐metabolizing enzyme in L. pneumophila Lens strain. Our work revealed that 3 of these proteins, Lpl0780, Lpl0922 and Lpl1118 are specifically involved in virulence control and, particularly, in the early survival during host cell infection through the orchestration of virulence factors secretion within host cell. Lpl1118 is particularly required for replicative vacuole biogenesis. Five other proteins, participate in the formation and architecture of biofilms. One of them is more specifically involved in biofilm formation in the presence of nitric oxide. These results help to better understand the complexity and the specificity of c‐di‐GMP signaling pathways in L. pneumophila and should allow the exploration of more effective ways to fight this pathogen
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23

Soules, Régis. "Proprietes cooperatives de complexes polymetalliques des ligands squarate et thiosquarate." Toulouse 3, 1987. http://www.theses.fr/1987TOU30178.

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Etude de l'emploi d'un coordinat assembleur qui puisse par coordination avec le centre metallique utilise (metaux de transition du groupe viii) aboutir a un agencement a une dimension des motifs moleculaires par empilement d'entites monomeres ou par formation de chaines. Par utilisation du coordinat squarate sous ses formes oxygenees et soufrees, obtention d'un certain nombre de complexes de pt, pd, ni et cu repondant aux criteres fixes. Etude des structures de ces composes, de leurs proprietes physiques et de la relation structure-propriete. La nature du coordinat comme le caractere specifique de l'arrangement structural ont ete discutes pour une approche de la comprehension de la nature de ces proprietes physiques
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24

"Modeling Relationships between Cycles in Psychology: Potential Limitations of Sinusoidal and Mass-Spring Models." Master's thesis, 2019. http://hdl.handle.net/2286/R.I.53747.

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abstract: With improvements in technology, intensive longitudinal studies that permit the investigation of daily and weekly cycles in behavior have increased exponentially over the past few decades. Traditionally, when data have been collected on two variables over time, multivariate time series approaches that remove trends, cycles, and serial dependency have been used. These analyses permit the study of the relationship between random shocks (perturbations) in the presumed causal series and changes in the outcome series, but do not permit the study of the relationships between cycles. Liu and West (2016) proposed a multilevel approach that permitted the study of potential between subject relationships between features of the cycles in two series (e.g., amplitude). However, I show that the application of the Liu and West approach is restricted to a small set of features and types of relationships between the series. Several authors (e.g., Boker & Graham, 1998) proposed a connected mass-spring model that appears to permit modeling of more general cyclic relationships. I showed that the undamped connected mass-spring model is also limited and may be unidentified. To test the severity of the restrictions of the motion trajectories producible by the undamped connected mass-spring model I mathematically derived their connection to the force equations of the undamped connected mass-spring system. The mathematical solution describes the domain of the trajectory pairs that are producible by the undamped connected mass-spring model. The set of producible trajectory pairs is highly restricted, and this restriction sets major limitations on the application of the connected mass-spring model to psychological data. I used a simulation to demonstrate that even if a pair of psychological time-varying variables behaved exactly like two masses in an undamped connected mass-spring system, the connected mass-spring model would not yield adequate parameter estimates. My simulation probed the performance of the connected mass-spring model as a function of several aspects of data quality including number of subjects, series length, sampling rate relative to the cycle, and measurement error in the data. The findings can be extended to damped and nonlinear connected mass-spring systems.
Dissertation/Thesis
Masters Thesis Psychology 2019
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25

Orr, Elizabeth. "Blending in at the Cost of Losing Oneself: The Cyclical Relationship between Social Anxiety, Self-Disclosure, and Self-Uncertainty." Thesis, 2013. http://hdl.handle.net/10012/7611.

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Recent research has demonstrated that high social anxiety is associated with uncertainty about one’s self views and self-concept (Moscovitch et al., 2009; Stopa et al., 2010; Wilson & Rapee, 2006). However, no research has addressed potential mechanisms underlying the link between high social anxiety and low self-certainty nor has research examined whether this relationship is bi-directional. In the current research, I propose a cyclical model in which high social anxiety leads to low self-certainty, which in turn, feeds back into higher levels of social anxiety. I also propose that the relationship between high social anxiety and low self-certainty is mediated by the self-protective self-disclosure patterns employed by socially anxious individuals. In three interconnected studies, I examine the hypothesis that social anxiety, self-disclosure and self-certainty operate in a cyclical model. Study 1 provided a correlational test of the hypothesized feedback model in its entirety and demonstrated that honesty of self-disclosure was the most important and influential mechanism underlying the link between high social anxiety and low self-certainty. Experimentally manipulating the honesty of participants’ self-disclosures in Study 2 demonstrated that dishonest self-disclosures during a social task led to low self-certainty, but only amongst individuals high in trait performance anxiety. Finally, experimentally manipulating self-certainty in Study 3 demonstrated that low self-certainty led to high anticipatory anxiety about an upcoming self-disclosure task. Together, these results elucidate a cyclical maladaptive pattern in which low self-certainty as a result of self-protective self-disclosure leads to high social anxiety and a greater reluctance to self-disclose. Results from the three studies are discussed with respect to their theoretical implications and in relation to clinical applications for individuals with social anxiety disorder.
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26

Levin, Benjamin Diamon. "Probing the structure-function relationship of heme c containing bacterial proteins: monoheme cytochromes c and diheme cytochrome c peroxidase." Thesis, 2013. https://hdl.handle.net/2144/14093.

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Heme containing proteins and their reactivity play a central role in biological systems; they have a vast range of functions including electron transfer, catalysis, and respiration. Cytochromes c and heme c containing proteins have been used widely as model systems to understand how structure and dynamics lead toward function. In this thesis, a variety of biophysical methods are used to investigate two heme c containing model systems to gain insight into how redox potential and reactivity are modulated through changes in the local environment. Mitochondrial cytochrome c undergoes several pH dependent conformational rearrangements that involve different heme ligation and have associated changes in redox potential. Under basic conditions (pH greater than 8), the axial methionine (Met) residue is replaced by one of several nitrogen based ligands, usually a nearby lysine residue, and is coined the "alkaline transition". It is accompanied by a large downward shift in redox potential. The functional utility of this conformational change is not fully understood however it is strongly implicated in the signaling cascade for apoptosis. Bacterial monoheme cytochromes c exhibit similar phenomenological Met-loss behavior as a function of electrode material. In Chapter 2 we utilize Hydrogenobacter thermophilus cytochrome c552 as a model system for the assessment of redox thermodynamics and changes in redox potential associated with the Met-loss form. In Chapter 3 we extend our investigation to homologous cytochromes c. Bacterial cytochrome c peroxidases catalyze the two-electron reduction of hydrogen peroxide to water utilizing cytochrome c as an endogenous electron donor. Chapter 4 describes the first recombinant construct of the diheme Nitrosomonas europaea cytochrome c peroxidase (Ne CCP); a defining family member of constitutively active cytochrome c peroxidases. A variety of biophysical techniques were used to confirm similarity between the recombinant Ne CCP and native enzyme. Chapter 5 extends our investigation to the role of constitutively conserved glutamine and glutamic acid residues within the active site, and two conserved tryptophan residues; the first situated between hemes and the second distal to the active site. In Chapter 6, stopped flow spectroscopy is used to investigate the first intermediates of the Ne CCP catalytic mechanism.
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27

Lin, Ching-Cheng, and 林敬晟. "Relationships between stock of clam Cyclina sinesis and environmental factors in the estuary of Cigu River in southwestern Taiwan." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/33067051696778015668.

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碩士
國立臺灣大學
漁業科學研究所
97
The study mangrove area, which was located in the estuary of Cigu River in southwestern Taiwan has abundant biological resources. The clam Cyclina sinesis was one of the most common economical bivalve in the estuary. The data sampling was carried out from July, 2008 to June, 2008. The transect sampling was used to collect the clam stock and environmental factors. Clam’s morphology such as shell length, height, width, weight, age and density were investigated in the survey. The environmental factors, such as pH, salinity, temperature, dissolved oxygen, water content, organic matter, grain size and the proportion of mud/sand were also investigated. The results indicated that the clam was mainly concentrated in the Cigu River sector, which consisted of clam less than 3 cm shell length and 2 years old. The clam mainly distributed in the low and mid tidal zone. The aerial root zone of mangrove in high tidal zone became a boundary of the clam distribution. The density of the clam increased in March because of recruitment of juveniles which shell length less than 2 cm and age about 1 year old, and decreased in June because of fishing. The Cigu estuary could be divided into three sectors, such as Cigu River sector, small water channel sector, Sangu River which was composed of different water and sediment factors. PCA also indicated that the main variation of Cigu estuary and Cigu River sector were from sediment factors. In conclusion, Cigu River sector of Cigu estuary became the only habitat of the clam Cyclina sinesis because it possessed the environmental factors they preferred, especially in the fine sand sedimental environment with less mud, which could provide juvenile clam’s successful settlement and better growth and survival rate for adult clam. According to the clam’s morphological composition and density variation, the clam Cyclina sinesis in Cigu estuary had faced heavy fishing pressure.
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28

Ming-ChungWei and 魏銘忠. "Experimental study of relationships between various void parameters and liquefaction behavior for gravelly sand using cyclic simple shear." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/32657019087846948808.

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碩士
國立中興大學
土木工程學系所
94
The distributed range of the gravel layer is wide in Taiwan. On the topography, the gravel layers often appear in the low and flat place, such as the river valley , plain , tableland and hills areas. These areas are mostly densely populated and the industry is developed. The huge buildings and public constructions are numerous in the area. Taiwan lies between the Eurasia plate and Philippine''s sea plate, plates movement cause the seismic activity to be frequent. Chichi earthquake occurs on September 21 of A.D. 1999, Richter Magnitude of Earthquake (ML )is large to 7.3, and it causes the extensive and serious calamity . The rare gravel soil liquefaction phenomenon were found in Nantou County and Wufeng town from many liquefaction cases. Two kinds of admixture were selected in experiment, including gravel of single size (1”) and Ottawa sand respectively. Besides, a cyclic simple shear of large size instrument were used to the test of the liquefaction resistance for remolded samples . At the same time of the test, Bender Element were placed in the top of the sample to measure shear wave velocity . The critical liquefaction resistance curve for Andrus & Stokoe’s about shear wave velocity assessment method were drawed repeatedly. The measured results of shear wave velocity about this research, Pei-Cong Wu and Yuan-Wei Shi (2004) were integrated with Andrus and Stokoe’s(2000)data of gravel. Finally, the paper used regress analysis of Minimum of Misclassified Points to get the critical liquefaction resistance strength curve of the gravel layer where , a is equal to 0.033on the best-fitting curve,b is equal to 2.4 on the best-fitting curve,calculate the normalized shear modulus (Vsl) after correcting for the overburden pressure, is 270 m/s. The results of the test show that the minimum liquefaction resistance was observed for specimens with 40 % fines. The liquefaction resistence strength of gravel soil drop with increase of the content of fines. It is attributed to variations of microstructures of gravel sands and can be explained with variations in gravel skeleton and interfine void ratios according to the fines contents of gravel. For gravel soils with more than 40 % of fines contents, the gravel soils behave like clean sands and the liquefaction resistance increas with decreasing of gravel skeleton void ratio.
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Hong, Ming-Lin, and 洪明琳. "Experimental study of relationships between various void parameters and liquefaction resistance for sands with fines using cyclic simple shear." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/93987070248465524779.

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碩士
國立暨南國際大學
土木工程學系
94
The fines content of sandy soil is one of the major factors that contribute to the liquefaction resistance of granular soils. Currently, there is no consistent conclusion that relates the fines contents and liquefaction resistance quantitatively. Series stress-controlled, cyclic simple shear tests were performed on remolded specimens consisted with Kaolinite and Shankan sands. Specimens with various fines contents and void ratios were cyclically sheared to systematically study the relationships among the fines contents, liquefaction resistance of soils, and different void parameters including global void ratios, sand skeleton void ratios, and interfine void ratios. The testing results show that the minimum liquefaction resistance was observed for specimens with 15 % fines. For specimens with fines contents less than 15 %, the liquefaction resistance decreases with increasing fines contents. However, the trend reverses for specimens with fines contents greater than 15 %. The inconsistence is attributed to variations of microstructures of silty sands and can be explained with variations in sand skeleton and interfine void ratios according to the fines contents of soils. For soils with fines contents less than 15 %, the soils behave like clean sands and the liquefaction resistance decreases with increasing sand skeleton void ratio.
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30

Huang, Yu-Chien, and 黃鈺茜. "The Relationship Between the Ovalization and Numbers of Cycle to Produce Buckling of Thin-Walled Tubes with Elliptical Notch under Cyclic Bending." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/08815923503539376913.

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碩士
國立成功大學
工程科學系碩博士班
97
This paper presents the experimental investigation of the buckling of the SUS 304 stainless steel tubes with elliptical notch subjected to symmetrical curvature-controlled cyclic bending. There are five kinds of different depths of elliptical notch (0.2, 0.4, 0.6, 0.8 and 1.0 mm) with a same width (1.0 mm) of SUS 304 stainless steel tubes. The tube bending machine and curvature-ovalization measurement apparatus were used to conduct the constant curvature-rate (0.035 m-1/s) cyclic bending test for obtaining the relationship between the ovalization and number of cycles. It can be observed from the experimental curve of the ovalization and the number of cycles could be divided into three stages, the initial, secondary and tertiary stages. These three stages are very similar to the three stages of uniaxial creep. The Bailey-Norton creep formulation was modified so that it can be used to simulate the curve for the initial and secondary stages. By comparing the theoretical simulation with the experimental data, good agreement between the experimental and theoretical results has been achieved.
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31

Ho, Ming-Yi, and 何銘益. "Mass-Spectrometric Investigations in the Structure-Activity Relationship of Cyclic Guanidine Derivatives in Peptide Signal Enhancement and Polypyridyl Ruthenium Complexes in E. Coli. Growth Inhibition." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/17059241988578573066.

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Abstract:
博士
淡江大學
化學學系博士班
97
The structure-activity relationship (SAR) of organic and inorganic compounds with biomolecules is intensively investigated in this thesis. The physical/chemical properties of these chemicals and their corresponding biological activities are analyzed by mass spectrometry. The first part is to study the formation of cyclic guanidine derivatives in lysine-containing peptides and their sensitivity in MALDI analysis. Six organic signal enhancement agents are synthesized by diamino compounds coupled with tetraethyl orthocarbonate. The yield of cyclization and lysine-specific guanidination reactions were prepared in ranges of 61 ~ 82 % and 2.1 ~ 76.5 % respectively. The enhancement of MALDI signal by cyclic guanidine derivatives is in a ratio of 7.6 ~ 15.1 times that result simplified spectra in tandem MS analysis. Modified structures associated with more electron donating property and hydrophobic characters present higher signal responds in MALDI analysis. The second part is to reveal the metabolism pathways of polypyridyl ruthenium (Ru) complexes in E. Coli. cells from proteomics study. Polypyridyl Ru-complexes are introduced with electron-donating and electron–withdrawing groups to study the inhibition of E. coli cells. By SAR studying, growth inhibitory capacity follows the order bidentate ligands (NN) of Ru(terpy)(NN)Cl2: bpy > dmbpy > dcbpyH2 ~ debpy). Up-regulation of EF-Tu and ribosomal proteins as well as down-regulation of ompF upon the Ru-complexes treatment present in quantitative proteomics study. Further analysis in mass spectrometry show that polypyridyl Ru-complexes are capable of binding to OmpF and EF-Tu proteins. Reduction of OmpF concentration was found to decrease Ru-toxicity which is demonstrated by adding 10% w/v sucrose in growth medium. It suggests that OmpF plays an important role in the Ru-complexes permeability into cells. These results provide an explanation of SAR of polypyridyl ruthenium complexes in transportation and cell-growth inhibition.
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