Thèses : « Differentiale influence »

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Lewis, Marcia Jackson. « The influence of differential sibling experiences on academic achievement ». Case Western Reserve University School of Graduate Studies / OhioLINK, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=case1056464687.

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Wilbert, Melissa. « Differential selective pressures acting upon the Influenza A genome : a comparative study / ». Online version of thesis, 2008. http://hdl.handle.net/1850/7916.

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Eva, Kevin Wayne. « The influence of differentially processing evidence on diagnostic decision-making / ». *McMaster only, 2001.

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Li, Jibin, et 李及彬. « Mechanisms underlying differential infection by pandemic H1N1 influenza A virus of human classically activated and alternativelyactivated macrophages ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B49617540.

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Macrophages have well-established roles in the primary response to pathogens and hold essential functions during innate and adaptive immunity. Under activation by different growth factors and cytokines, human monocytes have been shown to differentiate and polarize into two main types of macrophage, classically-activated macrophages (caMφ) and alternatively-activated macrophages (aaMφ), displaying distinct properties and phenotypes. For instance, caMφ secrete pro-inflammatory cytokines, whereas aaM secrete anti-inflammatory cytokines. Additionally, aaMφ displays stronger phagocytic ability and are equipped with different endosomal proteases. While it has been established that monocyte-derived macrophages can be infected by Influenza A virus, most studies utilized a macrophage population obtained by differentiation in the presence of autologous plasma. My research project aimed at systematically comparing susceptibility of the infection by Influenza A virus to the recently described caMφ and aaMφ. Here I show that monocytes cultured in presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon (IFN)-γ or in presence of macrophage colony-stimulating factor (M-CSF) and interleukin (IL)-4 or IL-10 can be differentiated into distinct populations. According to immunophenotyping results, a distinct expression profile was observed for Cluster of Differentiation (CD) 36, CD86, Mannose Receptor (MR or CD206), and Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin (DC-SIGN or CD209) among differentiated macrophages. Except for CD86 expression, my results were in accordance with previous reports and thus allowed me to classify all populations into caMφ (M1 macrophages), and aaMφ (M2a and M2c macrophages). I then assessed the susceptibility of the above mentioned macrophages to pandemic Influenza A/California/04/2009 H1N1 virus (CA04) infection. My results demonstrate a marked difference, caMφ showing low to moderate permissivity, whereas aaMφ – and in particular M2a macrophages – were consistently highly infected. In contrast, no difference was observed with Influenza A/WSN/1933 H1N1 virus (WSN/33) infection. Because sialic acids are regarded as the primary receptor for influenza virus, I investigated the cell surface distribution of sialic acids with α2-3 linkage (SAα-2,3) or α2-6 linkage (SAα-2,6) among the population of human macrophages. By using lectin staining with Maackia amurensis lectin (MAL) II and Sambucus nigra lectin (SNA), which bind sialic acids with α2-3 linkage (SAα-2,3) and α2-6 linkage (SAα-2,6) respectively, I found all the monocyte-derived macrophages exhibited a comparable expression of SAα-2,3 and SAα-2,6, which unlikely explain the differential susceptibility to infection by CA04. In addition to sialic acids, C-type lectins were also proposed to mediate entry of influenza viruses into macrophages. All macrophages expressed CD206 but only M2a expressed CD209. However assay aiming at interfering with CD209 binding (MAb blocking assay or EGTA treatment) did not inhibit pdmH1N1 infection. Surprisingly, infection in presence of EGTA, which is believed to reduce the functional ability of C-type lectins, exacerbated susceptibility of the macrophages. Altogether my results show that susceptibility to Influenza A virus infection of in vitro differentiated primary human macrophages is unlikely to rely on the sialic acid expression profile and is dependent on viral strain. Further studies are needed to understand what difference from caMφ and aaMφ – either phenotypic and/or biochemical – confer them distinct susceptibilities to some viral subtype/strain of Influenza A.
published_or_final_version
Pathology
Master
Master of Philosophy

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Rubinow, Katya. « Differential Endogenous Estrogen Exposure Influences Prefrontal Cortex Response to Acute Stress ». Yale University, 2006. http://ymtdl.med.yale.edu/theses/available/etd-06282006-142135/.

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The present study was conducted to determine the effect of differential endogenous estrogen exposure in rats on stress-induced changes in spatial working memory. Subjects comprised male (n=8) and female (n=10) Sprague-Dawley rats, which were trained to complete a T maze, delayed alternation task. Performance was scored as a percentage of trials during which the correct maze arm was selected. Subjects scores were recorded after 1 and 2 hours of restraint stress, as well as after 1 hour of unimpeded movement in a cage placed in the testing room. Restraint stress was effected through physical confinement within plastic, cylindrical tubing. Female subjects underwent each of the testing conditions twice, during periods of high and low endogenous estrogen exposure, as ascertained by microscopic examination of vaginal epithelial cells for estrous cycle stage determination. Females in proestrus (elevated endogenous estrogen exposure) subjected to 1 hour of restraint performed significantly worse than their baseline scores (p=0.0017) or females in estrus (low endogenous estrogen exposure) after 1 hour of restraint (p=0.00014). After 1 hour of restraint, females in proestrus also committed an increased rate of perseverative errors compared to females in estrus, although this increase did not achieve statistical significance (p=0.06). No appreciable differences existed among subject groups in baseline performance or subsequent to 2 hours of restraint stress. Resultant data indicate impaired working memory among female rats under conditions of stress in the context of elevated endogenous estrogen exposure. This study, then, suggests a potential synergistic effect of stress and estrogen in compromising prefrontal cortex function and, therefore, may lend insight into the observed sex-related disparity in the incidence of major depressive disorder and other anxiety-related mood disorders.

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Conradt, Elisabeth de Neuf 1980. « Differential Susceptibility to Rearing Influences : The Role of Infant Autonomic Functioning ». Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/11926.

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xvi, 132 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.
The Differential Susceptibility Hypothesis and the related Biological Sensitivity to Context theory contend that individuals with "susceptible" traits reap the benefits of positive rearing environments and exhibit better outcomes compared to their less susceptible peers. Studies have largely focused on physiological reactivity as an index of this susceptibility in children and adults, and most have measured physiology by grand mean changes from baseline to a stressor. The goal of this dissertation was to examine baseline Respiratory Sinus Arrhythmia (RSA) and RSA stress reactivity by taking advantage of analytical techniques modeling growth over time, as well as individual differences in this growth-using latent Growth Modeling (LGM) and Growth Mixture Modeling (GMM), respectively. Maternal sensitivity at 5 months and the quality of the attachment environment at 17 months were used as indicators of environmental conditions that might interact with infant susceptibility. Problem behavior and social competence were assessed at 17 months as measures of child well-being. Consistent with the theory of differential susceptibility, there were no significant differences in problem behavior or social competence among infants with low baseline RSA, but infants with high baseline RSA exhibited the lowest levels of problem behavior if reared in an environment that fostered security and more competence if their mothers exhibited greater sensitivity. Contrary to hypotheses, LGM analyses revealed that withdrawal of infant RSA appeared to buffer the impact of being reared in an environment that fostered disorganization, as infants with disorganized attachment histories exhibited the lowest number of problem behaviors. Two distinct groups of children were identified by GMM analyses: a class of infants with low RSA that decreased across the still-face episode, and a class of infants with high RSA that increased across this episode. Class by maternal sensitivity interactions were significantly predictive of social competence, with the high increasing class emerging as the group most susceptible to environmental influences, consistent with the differential susceptibility hypothesis. This dissertation adds importantly to both the sharpening and extension of theories of differential susceptibility.
Committee in charge: Jennifer Ablow, Chairperson, Psychology; Philip Fisher, Member, Psychology; Jeffrey Measelle, Member, Psychology; Jane Squires, Outside Member, Special Education and Clinical Sciences

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Pete, Kristof, et Jan Kantola. « Regional House Price Differentials in Sweden : Factors that Influence the Choice of Location ». Thesis, Jönköping University, JIBS, Economics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-775.

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The purpose of the thesis was to study price differentials of housing in and outside of Swedish cities. When doing so, the average price of detached houses in every Swedish municipality and city was taken. The prices were based on the purchasing sum (köpeskillinen) while the investigated time period was 1995 and 2005. To separate between the different areas in Sweden, the country itself was divided into two separate regions; south, and north. South was used twice, once with the three major city areas (Stockholm, Göteborg and Malmö/Lund) included and once when they were not. Within each region two groups of locations could be differentiated; economic centres (Stockholm as an example) and sub-municipalities (Danderyd as an example). Economic centers represented “in cities” and sub-municipalities “outside of cities”. In addition to the main purpose, we also wanted to examine what variables that are affecting the price of housing. Therefore; according to our theoretical background, income, working opportunities and availability of teachers were the important factors.

The empirical analysis signified that there is a clear average price differential between economic centers and sub-municipalities in all three regions. Detached houses in economic centers have become more expensive relative to sub-municipalities. The largest difference can be observed in the three major city areas, where the most extreme price changes have occurred. Consequently, it can be said that working opportunities had the foremost effect on house prices in the majority of our research areas. It was also found that income had a significant influence at several locations. Teachers per 100 students had on the other hand little or no effect at all on house prices. Moreover, where it was significant it affected houses prices negatively.

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Mahay, Daljeet. « Differentiated mesenchymal stem cells enhance nerve regeneration by trophic influences ». Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491336.

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Schwann cells (SC) are essential facilitators for peripheral nerves following injury by releasing supporting neurotrophic factors that provide physical support and guidance for regeneration. In vitro these cells are slow growing, hence not well suited to a tissue engineering approach to nerve repair. To consider alternatives, adult rat bone marrow mesenchymal stem cells (MSC) were differentiated (dMSC) into SC-like cells using an established cocktail of growth factors. Qualitative reverse transcriptase polymerase chain reaction (RT-PCR), western blotting and immunocytochemistry approaches showed that dMSC expressed glial cell markers and SC associated neurotrophic factors at a transcriptional and translational level. To further assess the properties of the dMSC, the cells were co-cultured with dorsal root ganglia (DRG) neurons and the secretion of the neurotrophic factors was evaluated. The neurite outgrowth of the DRG neurons was enhanced in co-culture with dMSC. Like SC, dMSC were responsible for the stimulation of longer and branched neurites in the co-culture model. The neurite outgrowth of DRG neurons was enhanced when co-cultured with dMSC due to trophic influences. Studies with ELISA methodology and blocking antibodies showed that this effect was due to the predominant release of brain derived neurotrophic factor and nerve growth factor which were up-regulated in dMSC following co-culture. This finding was confirmed by the addition of preconditioned medium from the dMSC and the expression of tropomyosin-related kinase receptors in the DRG neuron co-cultures. The functional properties of the dMSC were further elucidated in vivo by transplanting green fluorescent protein (GFP) transfected cells using a poly-3-hydroxybutyrate conduit in a rat sciatic nerve injury model. The regenerative capacity was evaluated after I and 2 months at the distal nerve stump by transmission electron microscopy. The number of myelinated regenerated nerve fibres was greater in the 2 months post-transplantation compared to the 1 month groups. The survival of the transplanted cells was confirmed by the detection of the GFP plasmid by quantitative PCR and the GFP expression in the cells by quantitative RT-PCR. For a further extension of the study, human-derived MSC from three patients were differentiated along a SC lineage and displayed SC characteristics. The results of this thesis further support the notion that MSC differentiated into SC-like cells display cellular, molecular and functional characteristics of SC to provide therapeutical substitutes for nerve regeneration following injury.

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Sarfaraz, Wakil. « The geometric influence of domain-size on the dynamics of reaction-diffusion systems with applications in pattern formation ». Thesis, University of Sussex, 2018. http://sro.sussex.ac.uk/id/eprint/79452/.

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This thesis presents through a number of applications a self-contained and robust methodology for exploring mathematical models of pattern formation from the perspective of a dynamical system. The contents of this work applies the methodology to investigate the influence of the domain-size and geometry on the evolution of the dynamics modelled by reaction-diffusion systems (RDSs). We start with deriving general RDSs on evolving domains and in turn explore Arbitrary Lagrangian Eulerian (ALE) formulation of these systems. We focus on a particular RDS of activator-depleted class and apply the detailed framework consisting of the application of linear stability theory, domain-dependent harmonic analysis and the numerical solution by the finite element method to predict and verify the theoretically proposed behaviour of pattern formation governed by the evolving dynamics. This is achieved by employing the results of domain-dependent harmonic analysis on three different types of two-dimensional convex and non-convex geometries consisting of a rectangle, a disc and a flat-ring.

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Wieland, Bernhard [Verfasser]. « Reduced basis methods for partial differential equations with stochastic influences / Bernhard Wieland ». Ulm : Universität Ulm. Fakultät für Mathematik und Wirtschaftswissenschaften, 2013. http://d-nb.info/1038004780/34.

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Xin, Yuxiang. « The influence of educational preferences and occupational levels on gender earnings differential in Sweden ». Thesis, Umeå universitet, Nationalekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-118706.

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Iskander, Jeannette Marie. « Delinquent Peer Relationships as a Mediator of the Differential Effects of Social Withdrawal and Behavioral Inhibition on Delinquency ». University of Dayton / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1366381213.

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Kingston, Deborah. « How do differential conceptualisations of voice-hearing influence attributions and behavioural intentions towards voice-hearers ? » Thesis, University of Lincoln, 2014. http://eprints.lincoln.ac.uk/18967/.

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Background: Stigmatisation negatively affects those being stigmatised. Anti-stigma campaigns suggest that biogenetic explanations reduce attributions of personal responsibility towards those with a mental illness. This study focused on one experience: Voice-hearing, which is associated with mental illness, namely schizophrenia, but may be considered to be a common experience, as at least 10% of the general population will hear voices at some point in their lives. There are multiple theories on the mechanisms that underlie voice-hearing experiences. However, each theory has strengths and limitations and there is limited empirical evidence to support the view that one theory is superior to others. The primary aim of this study was to test whether attributions, emotional responses and behavioural intentions towards voice-hearers were sensitive to differential conceptualisations of voice-hearing. The secondary aims were (a) to test attribution theory and identify attributions and emotional mediators that influence behavioural intentions and (b) to explore the extent to which various socio-demographic characteristics influence attributions. Methodology: 1,004 members of the general public were recruited using online resources. They completed self-report questionnaires online. Attributions, emotional and behavioural responses were measured using an adapted attribution questionnaire, which also contained questions related to familiarity. Results: Analysis of Variance (ANOVAs) found that four out of five attributions were not sensitive to conceptualisations offered. The attribution of personal responsibility was sensitive to conceptualisations. Responses from the biogenetic conceptualisation were significantly lower that the responses from the cognitive conceptualisation. There was no statistical significance between conceptualisations and (a) emotional responses (b) behavioural intentions, or (c) behavioural outcomes. Mediation analyses indicated that there was an indirect relationship between four out of five attributions and behavioural intentions, which were mediated by emotional responses. Fear was the strongest predictor of coercive behaviours and was negatively associated with helping behaviour. The construct ‘pity’ appeared to be viewed as a negative emotion, as results for this construct were similar to those of anger and fear. Correlation analysis demonstrated a small-to-medium sized relationship between behavioural intentions and behavioural outcomes, which was added to an adapted attribution pathway model. Additional analyses found that stressful life experiences produced neither a direct nor an indirect relationship with behavioural intentions and appeared to be the least stigmatising of the six causal explanations. Further correlation analysis found that professional familiarity was associated with a reduction in attributions of dangerousness. However, there were only small associations between socio-demographic variables and attributions. 1314, RIP, UofN:4149204, UofL:06075465 Research Project Resubmission Page 9 of 193 similar to those of anger and fear. Correlation analysis demonstrated a small-to-medium sized relationship between behavioural intentions and behavioural outcomes, which was added to an adapted attribution pathway model. Additional analyses found that stressful life experiences produced neither a direct nor an indirect relationship with behavioural intentions and appeared to be the least stigmatising of the six causal explanations. Further correlation analysis found that professional familiarity was associated with a reduction in attributions of dangerousness. However, there were only small associations between socio-demographic variables and attributions. Conclusions: These finding are unique in that they extend research into stigmatising attributions towards voice-hearers and extend attribution theory. The biogenetic conceptualisations lowered attributions of personal responsibility, but mediation analysis suggests that attributions of personal responsibility were positively associated with increased social distance and coercive behavioural intentions. These results have clinical implications as the differences between medical and psychological approaches reflect the different conceptualisations offered to service-users within mental health services. The least stigmatising conceptualisation appeared to be Family Intervention. This was the only conceptualisation that utilised a bio-psycho-social model, Future research should focus on whether, in practice, this would be the least stigmatising conceptualisation used within mental health services. Further consideration should be given to its use in future anti-stigma campaigns.

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Cox, Violet O. « DO FEATURE IMPORTANCE AND FEATURE CENTRALITY DIFFERENTIALLY INFLUENCE SEMANTIC KNOWLEDGE IN INDIVIDUALS WITH APHASIA ? » Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1258671486.

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Wenzel, Marcus Fredrick-Lynn. « Middle School Teacher Beliefs about Classroom Diversity and their Influence on Differentiated Instructional Practices ». PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3612.

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Diversity across U.S. classrooms is on the rise which is leading to renewed calls for teachers to meet individual learning needs. Studies indicate the failure to address individual learning needs can lead to higher rates of student disengagement, off-task behaviors, and diminished learning outcomes. Differentiated instruction is an approach to teaching that meets the growing diversity of individual learning needs by considering students' readiness, interest, and learning styles. Differentiated instructional approaches help teachers meet individual learning needs by allowing them to modify instruction as needed. However, despite the apparent benefits of differentiated instruction, teachers are hesitant to abandon other educational models. Research has shown beliefs about student learning influence teachers classroom practices. If teachers do not possess beliefs supporting differentiated classroom practices, then calls for additional implementation may go unheeded. Thus it is important to examine teacher beliefs that may help or hinder implementation of differentiated instructional practices. The purpose of this study was to explore teacher beliefs connected to teaching, learning, and differentiated instruction in diverse classrooms. This study used qualitative case study methodologies to interview, survey, and observe the beliefs and practices of four white, female, veteran middle level educators operating in diverse classroom settings. Data analysis revealed the following themes: (a) differentiated instruction is considered essential, (b) teachers' diversity definitions influenced their differentiated instructional strategies, (c) the classroom environment influences teachers self-efficacy, and (d) professional development sessions support differentiated instructional practices. Conclusions drawn from this study may be used to help improve teacher practices--and ultimately learner outcomes--by informing teacher preparation and professional development, state and local educational policies, and curricular reform efforts.

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Nzanza, Bombiti. « Yield and quality of tomato as influenced by differential Ca, Mg and K nutrition ». Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-05152008-144742.

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Radovic, Sendra Darinka. « Girls and school mathematics in Chile : social influences in differential attainment and mathematical identities ». Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/girls-and-school-mathematics-in-chile-social-influences-in-differential-attainment-and-mathematical-identities(e7394296-7994-40b2-b37c-d3d0a85198a0).html.

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Girls' relationship with mathematics has been an extensive and contested area of investigation during the last 40 years, mainly in developed countries. This contrasts with the small amount of research from developing countries, where the topic has been largely neglected but may present different challenges. In Chile, such lack of empirical evidence is surprising, particularly because of several national reports describing attainment differences in the national assessment test (SIMCE), where girls are consistently outperformed by boys. Currently, there are no studies which systematically explore gender differences in attainment in Chile. In addition, only a small number of studies have tried to explain why these differences, as well as others in engagement, attitudes and enrolment in mathematics, arise in this country. The main goal of this thesis is to critically examine these issues by investigating how girls relate to mathematics during early adolescence in Chile, and how such relationships are influenced/mediated by certain social variables (e.g. social class, classroom cultures and peer group identities).In order to do this, this thesis has adopted a mixed methods approach, thus linking analysis and results from studies that use both quantitative and qualitative methodologies. Firstly, I investigate the size and distribution of the gender attainment gap in Mathematics in Chile using a Multilevel approach to analyse data from the national census of educational quality (SIMCE). Here, I analyse the naturalization of gender differences based on results, and conclude that differences found in attainment between boys and girls are small and dependent on socioeconomic status. I then explore how girls' subjective relationships with mathematics are constructed, and how different social influences mediate this process. Using the concept of Mathematical Identities [MIs] as a main tool I explore the influence of social variables on the construction of girls' MIs in Chilean classrooms and I also consider how teaching practices and peer social relations in the classroom mediate these identities. A key finding here is the positive relationship between students' perceptions of their teaching as student-centred and more positive MI, which is in fact the same for girls and boys. A second key finding is that both representational and enacted aspects of girls' MI are mediated by their relationship with peers and peer groups. This mediation process can be described as a negotiation of different forms of belonging to social groups, which involved also the negotiation of different MIs inside the classroom. The main conclusion of this thesis is that in order to understand the role of gender in mediating girls' relationships with mathematics, we need to acknowledge the profoundly situated nature of this relationship in the cultural practices of the classroom, including mathematical practices, but also peer group practices. This argues against discourses that essentialise and naturalize 'gendered relationships with mathematics' which appear to be pre-dominant in the collation of national assessment data (like SIMCE) where categories such as gender, class, ethnicity etc. are viewed as causal or explanatory rather than produced 'in practice'.

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Zhao, Y. Y. « Differential-influence of hypertension and oxidative stress on the adrenomedullin / intermedin receptor system in cardiomyocyte hypertrophy ». Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487590.

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Reactive oxygen species (ROS) contribute to hypertension and development of left ventricular. hypertrophy (LVH). ROS are also implicated in potentially counterbalancing processes, through stimulation of oxygen-sensitive gene expression. The vasodilator substance, adrenomedullin (AM), a member of the calcitonin gene-related peptide (CORP) family, is upregulated under conditions of oxidative stress and can attenuate ventricular remodelling. The purpose of this . study was to compare AM and the newly discovered and structurally-related peptide, intermedin (IMD), along with the associated CL receptor and receptor activity modifying proteins (RAMPS 1-3), focusing on processes contributing to their upregulation in ventricular cardiomyocytes. Two appropriate experimental models were used: the spontaneously hypertensive rat (SHR), which exhibits compensated LVH at 20 weeks of age; the Sprague-Dawley rat made. hypertensive by treatment with the NO synthase inhibitor, Nro-nitro-L-arginine methyl ester (LNAME), which develops LVH by 16 weeks of age. Robust increases in IMD mRNA expression, greater than those' that of AM, were observed in both SHRs and L-NAME treated rats, suggesting a important role for IMD in myocardial remodelling. In the L-NAME model, which exhibited more significant myocyte hypertrophy and oxidative stress, effects of blood pressure lowering using hydralazine / hydrochlorothiazide, antioxidant therapy with vitamin C / Tempol, and treatment with nifedipine I atenolQl to target hypertension and ischemic insult were assessed. These studies demonstrated that upregulation ofIMD at1d RAMP 1 occurs mainly as a result of oxidative stress, whereas AM and RAMPs 2 and 3 are induced by 'pressure overload. Similar to AM, IMD had' a direct antihypertrophic action in vitro and upregulated IMD could therefore counter-regulate hypertrophy in vivo, possibly through increased AM receptors, viz. the CL-rec.eptor with RAMP 2 and/or 3. The concordance of IMD and RAMP-l upregulation indicates, a CORP-type receptor action; considering also a lack of response to blood pressure reduction alone, IMD may possibly, as does CORP, serve primarily an anti-ischemic function.

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Scheffel, Lucia. « Do feature importance and feature relevance differentially influence lexical semantic knowledge in individuals with aphasia ? » Thesis, Kent State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3618930.

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This study investigated two classifications of semantic features, feature importance and feature relevance, to verify if they differentially influence lexical semantic knowledge in individuals with aphasia. Feature importance is defined as "how important a feature is in defining a concept" (Hampton,1979), while feature relevance represents the "core meaning of a concept" (Sartori, Lombardi & Mattiuzi, 2005).

A sorting task was used with 20 volunteer participants with aphasia to investigate the semantic processing involved in the association of semantic features with nouns. A corpus of 18 nouns was displayed in front of each participant in groups of three along with a card containing the word "UNRELATED." The participants were given a deck of 18 cards containing features corresponding to the nouns and to the unrelated category, and were verbally instructed to sort the deck of cards into each of the four designated piles. The semantic features on the cards were rated as high, mid and low importance (HI, MI, LI) and high, mid and low relevance (HR, MR, LR).

Analysis was completed using a two-way between-subjects ANOVA to determine was whether the mean scores at the three different levels (e.g., low, mid and high) of importance and relevance differed, and to analyze if there was an interaction between the two classifications. The participants were able to assign high importance features with nouns more accurately than they did mid and low importance features. Feature relevance did not differentially influence noun-feature association. These results indicated that the ability of individuals with aphasia to accurately associate features with nouns is influenced by levels of feature importance.

In conclusion, this study found that individuals with aphasia are more cognitively sensitive to high level versus low level feature importance and the effect does not extend to a mid level of importance. The study also demonstrated that the levels of feature relevance did not differentially influence the ability of individuals with aphasia to associate semantic features with their appropriate nouns. Potential clinical implications and study limitations were discussed.

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Scheffel, Lucia. « Do Feature Importance and Feature Relevance Differentially Influence Lexical Semantic Knowledge in Individuals with Aphasia ? » Kent State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=kent1370971542.

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Gallagher, Kristel M. « It’s the Thought that Counts : Framed Exercise Outcomes Differentially Influence Physical Activity in Young Adults ». Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1247600343.

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Gallagher, Kristel M. « It's the thought that counts framed exercise outcomes differentially influence physical activity in young adults / ». [Kent, Ohio] : Kent State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1247600343.

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Thesis (M.A.)--Kent State University, 2009.
Title from PDF t.p. (viewed Mar. 31, 2010). Advisor: John Updegraff. Keywords: Message framing; motivation; exercise; health communication; health persuasion. Includes bibliographical references (p. 34-40).

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Koterba, Michael T. « Differential influences of storm and watershed characteristics on runoff from ephemeral streams in southeastern Arizona ». Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/191126.

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Relationships between thunderstorm and watershed variables and runoff from or within semiarid watersheds at Walnut Gulch, Arizona were examined. Variables showing greater sensitivity to basin and storm size were better flow predictors. Stepwise regression with three increasingly nonlinear algebraic models showed mean storm depth was the best simple predictor of runoff. Predictions improved using storm volume, a product of storm depth and areal extent. Initial runoff to streams was best described as a highly nonlinear function of storm and watershed variables. Runoff from a basin was a more linearized function of similar variables. The above differences were ascribed to channel transmission losses, reductions in runoff moving down initially dry channels. For a given basin and small storms, loss to runoff ratios exceeded 10:1 and were highly variable. Ratios were similar and less than 0.5:1 for storms centrally located over a basin and generating sufficient initial runoff to minimize flow variation due to losses. Losses increased disproportionately with basin size. Antecedent rainfall and first summer flows also affected rainfall runoff relationships in a differential manner. Wet conditions enhanced runoff more from larger versus smaller storms. First summer flows were less than expected probably because of higher soil infiltration and channel losses at the onset of summer storms. Overall, as storm size decreased or basin area increased, initial runoff was more often a localized phenomenon and downstream flow more dependent on storm depth, extent, location, and seasonal timing and basin channel losses, but less dependent on antecedent rainfall. Consequently, storm depth accounted for only 60% to 70% of the variation in flows while storm volume, antecedent rainfall, channel losses, and first summer flows explained 80% to 90%. Finally, oversimplifying storm or watershed variables or analytical methods led to errors in assessing their affect on runoff. It was also determined that current arguments supporting a recommendation to delete smaller, frequent annual floods to better fit remaining data to flood frequency curves were oversimplified. Distributed rainfall - runoff models with channel losses and regional storm depth - area - frequency data may be the way to develope flood curves for semiarid basins with short runoff records.

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Vollet, Justin William. « Differential Susceptibility to Social Network Influences on School Motivation in a Cohort of Sixth Graders ». PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/79.

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Students' classroom engagement is a strong predictor of positive educational outcomes including academic achievement, GPA, and standardized test scores. Most existing research has focused on the role of quality parenting and teaching in the development of student engagement. However, some research has shown small, yet significant effects of influences from students' peer groups on the development of their engagement. The goal of this study was to explore whether some children are more susceptible to the effects of their peer groups, and to examine a series of possible factors that might amplify the influence of a target students peer group on the development of that students' own engagement over the course of an academic year. In a re-analysis of an existing data set (Kindermann, 2007), peer group profiles of student engagement were examined as predictors of changes in individual engagement from fall to spring. It was expected that peer groups' levels of engagement would vary in their predictive power for changes in students' own engagement over the school year, depending upon individual levels of peer relatedness, the number of peers with whom the student affiliates with, student perceptions of parental involvement, as well as person-to-group differences in engagement. Gender differences were expected to be non-significant. As expected, results from two sets of analysis indicate no significant gender differences in susceptibility to peer influence. Furthermore, results suggest that susceptibility to peer influence on school engagement may depend upon the number of peers with whom a student affiliates with, parental involvement, as well as person-to-group differences in engagement. However, contrary to expectations, results suggest that a student's susceptibility to peer influence may not depend upon self-reported peer relatedness. Details of the analyses, results, strengths, limitations, and implications for future research are discussed.

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Collins, Tammy L. « The Differential Influence of Disrupted Family Processes by Gender on Behavioral Health Risk in Court-Involved Juveniles ». The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1316492791.

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Thurman, Carol Jenetha. « A Monte Carlo Study Investigating the Influence of Item Discrimination, Category Intersection Parameters, and Differential Item Functioning in Polytomous Items ». Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/eps_diss/48.

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The increased use of polytomous item formats has led assessment developers to pay greater attention to the detection of differential item functioning (DIF) in these items. DIF occurs when an item performs differently for two contrasting groups of respondents (e.g., males versus females) after controlling for differences in the abilities of the groups. Determining whether the difference in performance on an item between two demographic groups is due to between group differences in ability or some form of unfairness in the item is a more complex task for a polytomous item, because of its many score categories, than for a dichotomous item. Effective DIF detection methods must be able to locate DIF within each of these various score categories. The Mantel, Generalized Mantel Haenszel (GMH), and Logistic Regression (LR) are three of several DIF detection methods that are able to test for DIF in polytomous items. There have been relatively few studies on the effectiveness of polytomous procedures to detect DIF; and of those studies, only a very small percentage have examined the efficiency of the Mantel, GMH, and LR procedures when item discrimination magnitudes and category intersection parameters vary and when there are different patterns of DIF (e.g., balanced versus constant) within score categories. This Monte Carlo simulation study compared the Type I error and power of the Mantel, GMH, and OLR (LR method for ordinal data) procedures when variation occurred in 1) the item discrimination parameters, 2) category intersection parameters, 3) DIF patterns within score categories, and 4) the average latent traits between the reference and focal groups. Results of this investigation showed that high item discrimination levels were directly related to increased DIF detection rates. The location of the difficulty parameters was also found to have a direct effect on DIF detection rates. Additionally, depending on item difficulty, DIF magnitudes and patterns within score categories were found to impact DIF detection rates and finally, DIF detection power increased as DIF magnitudes became larger. The GMH outperformed the Mantel and OLR and is recommended for use with polytomous data when the item discrimination varies across items.

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Rothwell, Virginia Leigh. « The Relationship between Attitudes toward Deviance and Deviant Behavior : The Influence of Science, Individualism, Social Bonds and Deviant Peers ». Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/28988.

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Various sociological theories of deviance have demonstrated the importance of an individualâ s attitudes toward deviance in determining whether or not that individual will engage in deviant behavior. This research contributes to the theoretical and empirical literature on deviant behavior by examining the strength of two cultural factors, the scientific worldview and individualism, in predicting an individualâ s attitudes toward deviance when tested alongside the tenets of other predominate individual level theories of deviance, namely Hirschiâ s (1969) social control theory and Sutherlandâ s (1939) differential association theory. The sample for this analysis is 202 students from a large research university in Southwest Virginia. The findings of this research lend support to Sutherlandâ s (1939) differential association theory and to the scientific worldview as significant predictors of tolerant attitudes toward deviance. Several of the bonds of Hirschiâ s (1969) social control theory were also supported in this research; however, some failed to predict deviant behavior, leading to the conclusion that future research should focus on clearly elucidating the conceptualization of the social bonds forwarded in the original theory. Finally, the cultural ideology of individualism was not a significant predictor of tolerant attitudes toward deviance in this study. Future empirical studies should work to more clearly operationalize this variable as Hawdon (2005) described it and investigate the variables significance as a predictor of tolerant attitudes toward deviance.
Ph. D.

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De, Bruin IIse. « Exploring how objects used in a Picture Vocabulary Test influence validity ». Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/25218.

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Multilingualism in the classroom is one of the many challenges found in the cumbersome bag that the South African education system is carrying over its shoulders at present. Globalisation and migration have added to the burden as factors adding further diversity to the already diverse classroom. In South Africa the spotlight is focused on equality. Equality is expected in the education system, and in the classroom and especially in tests. With 11 official languages excluding the additional languages from foreign learners it has become a daunting task to create tests that are fair across multilingual learners in one classroom. Items in tests that function differently from one group to another can provide biased marks. An investigation was done in order to detect any biased items present in a Picture Vocabulary Test. The study was lead by the main research question being: How do objects used in a Picture Vocabulary Test influence the level of validity? The first sub research question was: How do objects used in a Picture Vocabulary Test influence the level of validity? The next sub question was: To what extent is an undimensional trait measured by a Picture Vocabulary Test? The final subquestion was To what extent do the items in a Picture Vocabulary Test perform the same for the different language groups? This Picture Vocabulary Test was administered to Grade 1 learners in Afrikaans, English or Sepedi speaking schools within Pretoria, Gauteng. The sample totalling 1361 learners. The process involved a statistical procedure known as Rasch analyses. With the help of Rasch a Differential Item Functioning (DIF) analysis was done to investigate whether biased items were present in the test. The aim of this study it is to create greater awareness as to how biased items in tests can be detected and resolved. The results showed that the items in the Picture Vocabulary Test all tested vocabulary. Although items were detected that did indeed perform differently across the three language groups participating in the study.
Dissertation (MEd)--University of Pretoria, 2010.
Science, Mathematics and Technology Education
unrestricted

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Godon, Nicole. « Effet des materiaux d'environnement sur l'alteration du verre nucleaire r7t7 : influence des argiles ». Orléans, 1988. http://www.theses.fr/1988ORLE2045.

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On a entrepris des essais comparatifs sur differents materiaux argileux et on a suivi la cinetique de l'interaction eau/verre/materiau pendant 1 an. La presence d'argile a ete correlee avec la vitesse de corrosion du verre nucleaire et on a recherche le meilleur materiau pour elaborer des barrieres ouvragees empechant cette alteration

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Emery, Leigh M. « Experiences of service user involvement and their influence on identity ». Thesis, Canterbury Christ Church University, 2015. http://create.canterbury.ac.uk/13901/.

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Identity can be considered to be socially constructed and developed through narratives about ourselves and our experiences. Having socially valued roles may thus facilitate a positive identity. This study aimed to explore how the experiences of service user involvement (SUI) in health and social care services (specifically, being involved in staff recruitment) influenced the narrative identities of people with learning disabilities. Interviews were conducted with seven people with learning disabilities who had been service user representatives on NHS interview panels. These were analysed using thematic narrative analysis as a framework. All described positive narrative identities, but the degree to which SUI featured in the construction of narrative identities varied. Whilst some found the experience transformative, for others it was not an important part of their narratives. The findings suggest that such experiences formed just one of many narratives that participants drew from to construct their narrative identity.

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Rad, A. « The differential influence of allogeneic tumour cell death via DNA damage on dendritic cell maturation and antigen presentation ». Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1381828/.

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Dendritic cells (DC) respond to danger signals from tissue injury by amplifying their immune-inducing capacity. In the cancer context, this may lead to in vivo anti-tumour synergism between DC and DNA-damaging chemotherapeutic agents. Neither the interaction between DC and dying tumour cells, nor whether different ways of inducing cell injury can deliver danger signals of different strength to DC, has been studied rigorously. Furthermore, the physical interactions of DC with injured tumour cell, and whether physical contact is required for sensing danger signals, have not been clearly defined. Here we report that co-culture of immature DC with tumour cells treated with the alkylating agents Melphalan and Chlorambucil leads to enhanced autologous and allogeneic T-cell activation, up-regulation of surface expression of MHC and costimulatory molecules, and increased interleukin (IL)-12 secretion. However, exposure of DC to tumour cells killed by Cytarabine or by freeze-thaw (primary necrosis) resulted in significantly less T-cell proliferation and IL-12 production, indicating that DC are able to sense and respond differentially to the mode of cell death. Exposure of DC to DNA purified from tumour cells treated with alkylating agents also increased their T-cell-stimulating capacity, expression of CD86, and IL-12 secretion, supporting the hypothesis that the activating effects of tumour cells are linked to the nature of the DNA damage. Furthermore, physical contact between DC and injured tumour cells is necessary for DC to sense and respond to danger signals. DC physically intereract with tumour cells via actinand microtubule-dependent phagocytic mechanisms. This is the first study that shows that DC respond differentially to killed tumour cells, depending upon the mechanism of DNA damage and consequent T-cell death.

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Blanton, Ann Linstrum. « Differential influence of vowels on oral and nasal intensity in nasalance scores and transpalatal transfer of acoustic energy / ». abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3329563.

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Saunders-Hastings, Patrick. « Modelling of Pandemic Influenza in Canada : Predicted Burden and Hospital-Resource Adequacy ». Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36589.

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For centuries, pandemic influenza has emerged at irregular and unpredictable intervals to cause widespread illness, hospitalization and death. Uncertainty surrounding the timing and severity of future influenza pandemics present challenges for preparedness and response efforts. The objective of this dissertation is to advance pandemic influenza knowledge and preparedness, through a series of interrelated articles that address the follow research questions: 1. What are the likely consequences of a pandemic flu event in Canada? 2. What do mathematical models tell us about preparing for such an event? 3. What is the best way to mitigate the consequences of an influenza pandemic? Six articles were prepared for submission in scientific, peer-reviewed journals. The first is a historical review of the burden of pandemic influenza. The second and third are systematic reviews of the effectiveness of interventions to interrupt pandemic influenza transmission. The fourth and fifth are research papers presenting a novel mathematical model, assessing the preparedness of the Canadian hospital system to accommodate expected surges in patient demand and evaluating intervention strategies to mitigate impact. The sixth is a policy-oriented paper discussing pandemic policy options within the context of public health ethics and risk management principles. Pandemic vaccination, antiviral treatment, voluntary isolation and personal protective measures were identified as the most cost-effective interventions available. Antiviral prophylaxis, community-contact reduction, school closure and quarantine were less effective, and tended to be associated with higher associated economic burdens. The timely implementation of layered intervention strategies appears likely to protect hospital-resource adequacy, though areas of Southwestern Ontario appear to be more vulnerable to surges in patient demand. However, the potential for high health and economic burdens, coupled with the uncertain severity of future pandemics, necessitates a flexibility in preparedness and response plans.

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McBride-Walker, Mercedes. « Standing out| The influence of organization culture and cultural values on a manager's willingness to meaningfully differentiate employee performance ». Thesis, Pepperdine University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1543409.

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This mixed-methodology study investigates the degree to which dominant organization culture and cultural values influence a manager's willingness to differentiate employee performance for the purpose of making meaningful talent decisions. Data were collected from 26 companies and a total of 45 individual participants. The findings suggest that specific values play a significant role in influencing a manager's willingness to differentiate employee performance regardless of dominant culture. All organizations have high and low performers, yet being willing to make tough performance calls for greater talent decision effectiveness may require embodying values that are considered countercultural. We argue that these values may need to be translated in the dominant culture for greater acceptance and assimilation, and recognize that companywide performance management programs may best be viewed as a collection of individual decisions that carry with them great tensions. Implications and limitations of the study are discussed.

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Jeon, Haesang. « The Influence of Social Networks and Supports on Health : Differential Pathways for Older Korean Immigrants and Non-Hispanic Caucasians ». Thesis, Boston College, 2013. http://hdl.handle.net/2345/3874.

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Thesis advisor: James Lubben
It has been shown that the effect of social networks and social support systems on health may be greater among immigrants who live away from their homeland and their natural social support systems. Despite the significance of social support systems, relevant research on minorities in the U.S. is limited. For this reason, the current cross-cultural study examined the pathways underlying different formations of social networks (kin vs. non-kin) and social support systems (emotional vs. instrumental), which affect depression symptoms and perceived general health among older Korean immigrants and non-Hispanic Caucasians in the United States. This analysis is based on the secondary data from the "Korean-American Elderly: Social Supports and Long-Term Care" study conducted in 1994. The data (n=424) were collected from non-Hispanic White Americans (n=201) and Korean immigrant elders (n=223) aged 65 and older residing in Southern California. Structural equation modeling (SEM) was used to test the proposed conceptual model designed to explain the direct and indirect relationships between social networks and social support on health outcomes. Empirical evidence from this study indicated different effect of one's social networks and social support on health by race/ethnicity. The result indicated that both kin and non-kin networks provided social support for Korean immigrants. Moreover, among social network measures, non-kin networks had a greater effect on social support for older Korean immigrants compared to kin networks. For non-Hispanic Caucasians, on the other hand, only kin network had a significant effect on social support systems. In addition, receiving instrumental support lowered the perceived general health among older non-Hispanic Caucasians. The work discussed in this paper pointed to the need to recognize the role of culture in assessing the effect of one's social networks and social support systems on health. This paper highlighted the characteristics of those older Korean-American and older non-Hispanic Caucasians who are most, as well as, least likely to benefit from social networks and social support systems. By utilizing the existing social networks and social support of diverse populations, we can improve overall health outcomes and serve the elderly community better
Thesis (PhD) — Boston College, 2013
Submitted to: Boston College. Graduate School of Social Work
Discipline: Social Work

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Pillar, Rachel Joanne, et rachel pillar@flinders edu au. « The Influence of Rolling Oil Decomposition Deposits on the Quality of 55Al-43.4Zn-1.6Si Alloy Coatings ». Flinders University. School of Chemistry, Physics and Earth Sciences, 2007. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20080108.132120.

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Uncoated defects in hot dip metal-coated steel products result from non-wetting of the steel surface by the molten alloy. The occurrence of uncoated defects is highly detrimental to product quality and production efficiency; uncoated defects compromise the appearance and anti-corrosion performance of hot dip metal-coated steel products and causes time delays in the application of subsequent surface treatments. Although many studies have been directed towards evaluating the effect of steel pre-heat temperature and oxidation on the formation of uncoated defects, fewer investigations have analysed how oil-derived residues remaining on steel surface following the cold rolling and furnace cleaning processes impact upon hot dip metallic coating quality. Furthermore, although a considerable amount of research has focussed on the process of deposit formation in lubricants used in other applications, the composition of oily residues remaining after the continuous annealing process, and the origins of these residues in the original rolling oil formulation, are poorly understood. The primary focus of the present work has been to gain an improved understanding of relationships between cold rolling oil composition, oil residue-formation characteristics and the occurrence of uncoated defects in 55Al-43.4Zn-1.6Si hot dip metallic coatings. Several key classes of rolling oil ingredients which decompose to leave high levels of thermally-stable residue have been identified. The thermal decomposition processes undergone by a variety ingredients within these classes have been studied under both oxidising and reducing conditions using Thermogravimetric Analysis (TGA) and Pressure Differential Scanning Calorimetry (PDSC) techniques, with chemical characterisation of the decomposition process and the resultant thermally-stable residue by infrared spectroscopy. Model blends of each ingredient in a typical cold rolling oil base ester have also been evaluated by TGA and PDSC to identify the impact of ingredient concentration and chemical structure on the amount of oily residue formed. The results of these investigations have been related to the impact of the ingredients on 55Al-43.4Zn-1.6Si hot dip metallic coating quality through the performance of industrial-scale hot dipping trials and hot dip simulation studies. In order to translate these results into a context more closely aligned with industrial conditions, the effect of processing variables, including furnace atmosphere and the availability/concentration of iron in contact with the rolling oil at the steel surface, on the decomposition process of a fully-formulated commercial cold rolling oil has also been investigated. The information gained can potentially be used to tailor operating conditions within the cold rolling/continuous hot dip metallic coating processes to enhance steel surface cleanliness. Finally, the deposit-forming tendencies of an array of different commercial cold rolling oils have been evaluated, leading to the development of a thermal analysis-based test for screening cold rolling oils with respect to their likely impact upon 55Al-43.4Zn-1.6Si hot dip metallic coating quality. This test, together with the understanding obtained on the effect of different rolling oil ingredients on hot dip metallic coating quality, can be used within the industry to formulate improved cold rolling oils.

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Zhang, Liang. « DIFFERENTIAL INNATE IMMUNE RESPONSES CORRELATE WITH THE CONTRASTING PATHOGENICITY OF THE EQUINE H7N7 INFLUENZA VIRUS DEMONSTRATED IN HORSES AND BALB/C MICE ». UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/151.

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Equine influenza virus causes a mild, self-limiting upper respiratory disease in its natural host. In stark contrast, equine influenza viruses of the H7N7 subtype produce lethal infection in BALB/c mice. This dissertation explored the mechanism underlying the differential pathogenicity of the equine H7N7 influenza virus observed in horses and BALB/c mice. Initially, a comparative study of the pathogenesis was conducted in BALB/c mice inoculated intranasally with a representative isolate of either H7N7 or H3N8 subtype equine influenza virus. All H3N8 virus-infected mice survived the infection whereas 100% mortality was documented for the mice receiving the H7N7 virus by day 8 post infection. Both viruses replicated to a similar degree in the lungs at the early stages of infection. However, after day 2 post infection until the death of the mice, the pulmonary viral loads of the H7N7 group were significantly higher than those of the control, whereas the H3N8 virus was eventually eradicated from the mice at day 7 p.i. Correspondingly, a vigorous pro-inflammatory cytokine response in the lung was induced by the H7N7 virus but not the H3N8 virus, which reflected a desperate attempt by the host immune responses to restrain the overwhelming infection. The H7N7 virus was poorly sensitive to the innate immune containment, resulting in a significant higher cumulative mortality rate than that of the control virus in chicken embryos aged 9 days and older. On the contrary, in horses, replication of the paired viruses was completely cleared by the host immune responses at day 7 p.i. and the infections produced an acute yet non-lethal illness, albeit the H3N8 virus induced generally more pronounced clinical manifestations than the H7N7 virus. The clinical severity correlated to the difference in cytokine-inducing capacity between the two viruses in horses, as evidenced by the finding that the H3N8 virus triggered significantly higher levels of gene transcription of multiple key inflammatory cytokines in the circulation than those seen for the H7N7 virus. In addition, equine peripheral monocyte-derived macrophages were found to be a target of equine influenza virus and can support the productive replication of the virus in vitro.

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Sullivan, Madsen Paul. « Effects of and Influences on Microbial Populations of Missouri Maize Fields ». BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7706.

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The role of individual soil microorganisms changes over the course of a plant's life - microorganisms that have no discernable role at one developmental stage may affect the plant later in its growth. Traditional analysis of the soil microbiome, which has focused principally on the relative abundances (RA) of individual organisms, may be incomplete, as underlying differences in population size cannot be addressed. We conducted a metagenomic analysis of soil microorganisms from various maize (Zea mays L.) fields at two depths, accompanied by crop yield components, to provide insight into influences of edaphic microbes on maize productivity under commercial maize production systems in Missouri. This study assesses the influence of fungi and bacteria, not only in terms of RA, but also in their estimated absolute abundances (EAA), derived by combining the results of Illumina HiSeq sequencing data and phospholipid fatty acid abundance data. Significant interactions were identified between maize yield components and soil microbes at critical developmental states. Most interactions between fungi and yield components were negative, with notable exceptions. Bacterial interactions were more complex, with most interactions during early ear development identified as positive, and most interactions during tasseling identified as negative. In addition to the effects that microbial populations have on yield, plant populations reciprocally changed the microbial community. Plant developmental state was the greatest predictor of bacteria, with the microbial communities present during the active growing season being most similar to each other, whereas the preplant microbiome and post-reproductive microbiome being most similar to each other. Fungal communities were primarily dependent on location.

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Olofsdotter, Susanne. « Anxiety among Adolescents : Measurement, Clinical Characteristics, and Influences of Parenting and Genetics ». Doctoral thesis, Uppsala universitet, Institutionen för neurovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-323578.

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Anxiety is the most commonly reported mental health problem among adolescents. Still, many adolescents in need of treatment are not detected and the clinical characteristics and etiological pathways of adolescent anxiety are under-researched topics. This thesis examined the clinical utility of the Swedish versions of the Spence Children’s Anxiety Scale (SCAS) and the clinical characteristics of multiple anxiety disorders among psychiatrically referred adolescents, and the influence of parenting and oxytocin gene (OXT) variants on anxiety among adolescents in the general population. Studies employed cross-sectional and longitudinal designs and were based on questionnaire, interview, and genotype data. Support for the reliability and validity of both SCAS and SCAS-P was obtained. The overall ability to predict anxiety among referred adolescents ranged from fair to excellent for both scales. Among adolescents psychiatrically referred for any reason, the prevalence of any anxiety disorder was 46%. Homotypic comorbidity was observed in 43%, and heterotypic comorbidity in 91%. Early adolescent anxiety influenced homotypic anxiety in late adolescence independent of parental rejection and control. The mediating role of parenting was small with indirect effect sizes no larger than one-tenth the size of direct effects, irrespective of the informant on parenting behavior. Significant interaction effects with positive and negative parenting were observed for OXT variants rs4813625 and rs2770378 in relation to social anxiety. The nature of the interactions was in line with the differential susceptibility framework for rs4813625, whereas for rs2770378, results indicated a diathesis–stress type of interaction. The findings suggest that psychiatrically referred adolescents with anxiety disorders are best characterized as a highly complex patient group and call attention to the necessity of structured assessment. For this purpose, this thesis provides evidence for the clinical utility of the SCAS; routine utilization of this questionnaire can improve detection of adolescents in need of anxiety treatment. Findings of this theses further suggest that the influence of positive and negative parenting behaviors on anxiety may be of greater importance among some adolescents than others, depending on individual differences in sensitivity to parenting. The etiology of anxiety among adolescents may therefore involve differential susceptibility effects of the interplay between genes and parenting behaviors.

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Michaud, Danielle. « The differential influence of knowledge of signals to importance on eighth graders' accuracy in representing content and organization of essays / ». Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61926.

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Budiyanto, Cucuk [Verfasser]. « The Reciprocal Influence of Parent-Subsidiary Relationships and Enterprise Systems Implementation : An Exploratory Study using Power Differential Perspective / Cucuk Budiyanto ». München : GRIN Verlag, 2018. http://d-nb.info/117822371X/34.

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Castilla, Rogelio Eduardo Fernandez. « The influence of differentials in child mortality by age of the mother, birth order, and birth spacing on indirect estimation methods ». Thesis, London School of Hygiene and Tropical Medicine (University of London), 1985. http://researchonline.lshtm.ac.uk/923207/.

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The objective of this investigation is to analyse the impact of differential mortality by birth order and age of the mother on the indirect estimates of child mortality. This indirect method was proposed by professor W. Brass and is based on reports about the number of children ever born and children surviving to women classified by age groups. The first step was to relax the constraints imposed on the method by the assumption that the risk of dying is invariant with birth order, mother's age and birth spacing patterns. To that effect, on the basis of the available evidence, a functional description of mortality by age of the child, which takes into account these differentials, was proposed. Then a beta-binomial probability distribution was used for describing fertility patterns by marriage duration and birth order, and a negative binomial distribution was adopted for describing nuptiality patterns. The models were tested using data from different countries and the results were satisfactory. All the necessary calculations to simulate proportions of children surviving (or dead) by age of the mother and number of children ever born were then executed on the basis of these three demographic models. Birth distributions by age of the mother and birth order were obtained by compounding the fertility model by marriage duration with the nuptiality model. Then, under certain assumptions, mean time-exposures to the risk of dying were calculated for children by birth order, current age of the mother, and parity. These exposures were combined with the functional description of mortality mentioned above, to yield proportions of children surviving by age and parity of the mothers. Adjusting factors by mother's age groups were calculated by relating these results to those obtained when mortality is assumed to be a function of the child's age only. These factors make estimates of mortality levels, obtained from reports from the younger mothers, comparable to the overall mortality for all children. They were applied to data from Peru and the results appeared to be very reasonable. An important conclusion from the analysis of the average exposures to risk for children by mother's age and parity is that the exposures are fairly constant by family size, while the variation in the proportions of children surviving is significant. The practical implication of these findings is that variations in the proportions of children surviving are basically caused by differential mortality. The application of the technique was illustrated with two practical examples. Proportions of children surviving by family size and age of the mother from Bolivia, 1976 Census, and from Guatemala, 1970 Census, were analysed. An enormous differential in mortality by family size was observed in both countries. The patterns of the relative risks by family size were very similar in both countries.

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Shigemoto, Yuuki. « Quantifying consumer perception of designer intent ». Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/276694.

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This thesis explores the relationship between designer intent and consumer response. A novel approach to evaluate the degree of correspondence between designer intent and consumer perceptions has been proposed. The empirical results have shown the influence of consumers’ cultural backgrounds on the way they perceive semantic and symbolic product personalities (characteristics of a product and its owner, respectively), comparing British and Japanese consumer groups. Semantic product personalities are more likely to be universally perceived and more easily intentionally elicited from consumers than symbolic product personalities. The research project consists of a pilot study (Phases I) and an experiment (Phase II) in which mixed methods of interview and survey are employed. Phase I seeks to explore the in-depth understanding of a designer’s thoughts by interviews, and to develop and test newly elaborated consumer surveys termed Designer-driven semantic differentials and Consumer-driven adjective selection. The findings have been considered to construct an analytical framework, characterised by Agreement among consumer perceptions and Correspondence between designer intent and the consumer perceptions, for evaluation of designers’ elicitation of intended product personalities from consumers. Phase II conducts a statistical examination of the impact of cultural difference on consumer perceptions under experimental conditions. The perception of target and non-target consumer groups as categorised by nationality were gauged by Designer-driven semantic differentials and Personality selection, specifically perception of USB sticks designed by three different designers. The survey results are analysed by using descriptive statistics, one-way ANOVA and Chi-squared test within the analytical framework. Subsequently, the results from Phase I and II are extensively discussed based on a framework based on brand personality and Affect Control Theory, both of which may involve potential impact on the development of design research into product development with emotional attachment. The scene is set for future research opportunities based on the approach and findings of this study.

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Szejner, Paul, William E. Wright, Flurin Babst, Soumaya Belmecheri, Valerie Trouet, Steven W. Leavitt, James R. Ehleringer et Russell K. Monson. « Latitudinal gradients in tree ring stable carbon and oxygen isotopes reveal differential climate influences of the North American Monsoon System ». AMER GEOPHYSICAL UNION, 2016. http://hdl.handle.net/10150/621424.

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The arrival of the North American Monsoon System (NAMS) terminates a presummer hyperarid period in the southwestern United States (U.S.), providing summer moisture that is favorable for forest growth. Montane forests in this region rely on winter snowpack to drive much of their growth; the extent to which they use NAMS moisture is uncertain. We addressed this by studying stable carbon and oxygen isotopes in earlywood and latewood from 11 sites along a latitudinal gradient extending from Arizona and New Mexico to Utah. This study provides the first regional perspective on the relative roles of winter versus summer precipitation as an ecophysiological resource. Here we present evidence that Ponderosa pine uses NAMS moisture differentially across this gradient. C-13/C-12 ratios suggest that photosynthetic water use efficiency during latewood formation is more sensitive to summer precipitation at the northern than at the southern sites. This is likely due to the fact that NAMS moisture provides sufficiently favorable conditions for tree photosynthesis and growth during most years in the southern sites, whereas the northern sites experience larger summer moisture variability, which in some years is limiting growth. Cellulose O-18 and C-13 values revealed that photoassimilates in the southern sites were produced under higher vapor pressure deficit conditions during spring compared to summer, demonstrating a previously underappreciated effect of seasonal differences in atmospheric humidity on tree ring isotope ratios. Our findings suggest that future changes in NAMS will potentially alter productivity and photosynthetic water use dynamics differentially along latitudinal gradients in southwestern U.S. montane forests.

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Hedlund, Isa. « The ANKK1 Gene and its Possible Influence on Alcohol Use : : The Role of Victimization and Parent-Child Relationship ». Thesis, Örebro universitet, Institutionen för juridik, psykologi och socialt arbete, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-86951.

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Risky alcohol use increases the risk of certain crimes such as drunk driving, spousal abuse and fighting. Around 60% of an individual’s alcohol use is attributable to genetic influences, however little is known regarding the specific genes that are involved in increasing the risk of risky alcohol use. Recent theories posit that some genes are so called susceptibility genes, meaning that carriers of certain genes or alleles are more susceptible both to positive and negative environments. The aim of the present study was to examine main and interaction effects of a possible susceptibility gene (ANKK1, which in previous research has been found to be related to risky alcohol use), and victimization as a negative environmental factor and parent-child relationship as a positive factor. Data were drawn from the RESUME project, and in the present study, 1.800 participants were included (47% males; 53% females; mean age of 22.15 years). Results showed no statistically significant main or interaction effect for ANKK1, but a statistically significant main effect was found for victimization and parent-child relationship. In conclusion, future research should include a larger sample size and use participants diagnosed with alcohol dependency. In addition, the susceptibility properties of ANKKI needs to be further examined, as the results from the present study indicate that ANKK1 is not a susceptibility gene.
Riskfylld alkoholkonsumtion kan öka risken för att vissa brott begås, såsom rattfylleri, partnervåld och slagsmål. Forskning har visat att omkring 60% av en individs alkoholkonsumtion kan förklaras av genetik, men det finns lite forskning kring just vilka gener som ökar risken för alkoholism. Nya teorier tror att vissa gener är så kallade sårbarhetsgener, vilket innebära att individer som bär på dessa gener eller särskilda alleler är mer sårbara för både positiva och negativa miljöfaktorer. Syftet med den nuvarande studien var att undersöka huvud-och interaktionseffekter av en potentiell sårbarhetsgen (ANKK1, som tidigare forskning visat har en påverkan på riskfylld alkoholkonsumtion), med utsatthet som den negativa faktorn och barn-föräldrarelation som den positiva faktorn. Data i form av enkätsvar och DNA prov från RESUME studien användes för den nuvarande studien, där 1,800 deltagare inkluderades (47% män; 53% av kvinnor; medelålder = 22.15). Resultaten visade inte på någon statistiskt signifikant huvud-eller interaktionseffekt för ANKKI, men det fanns en statistiskt signifikant huvudeffekt för utsatthet och barn-föräldrarelation. Slutsatsens som dras är att framtida studier bör fokusera på att ha ett större urval och använda sig av deltagare som är diagnosticerade med alkoholmissbruk. Utöver det bör framtida forskning fortsätta undersöka om ANKK1 är en sårbarhetsgen, eftersom resultaten från denna studie visar att den inte är en sårbarhetsgen.

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Leman, Hélène. « Probabilistic and deterministic analysis of the evolution : influence of a spatial structure and a mating preference ». Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLX026/document.

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Cette thèse porte sur l'étude des dynamiques spatiales et évolutives d'une population à l'aide d'outils probabilistes et déterministes. Dans la première partie, nous cherchons à comprendre l'effet de l'hétérogénéité de l'environnement sur l'évolution des espèces. La population considérée est modélisée par un processus individu-centré avec interactions qui décrit les événements de naissances, morts, mutations et diffusions spatiales de chaque individu. Les taux des événements dépendent des caractéristiques des individus : traits phénotypes et positions spatiales. Dans un premier temps, nous étudions le système d'équations aux dérivées partielles qui décrit la dynamique spatiale et démographique d'une population composée de deux traits dans une limite grande population. Nous caractérisons précisément les conditions d'extinction et de survie en temps long de cette population. Dans un deuxième temps, nous étudions le modèle individuel initial sous deux asymptotiques : grande population et mutations rares de telle sorte que les échelles de temps démographiques et mutationnelles sont séparées. Ainsi, lorsqu'un mutant apparaît, la population résidente est à l'équilibre démographique. Nous cherchons alors à caractériser la probabilité de survie de la population issue de ce mutant. Puis, en étudiantle processus dans l'échelle des mutations, nous prouvons que le processus individu-centré converge vers un processus de sauts qui décrit les fixations successives des traits les plus avantagés ainsi que la répartition spatiale des populations portant ces traits. Nous généralisons ensuite le modèle pour introduire des interactions de type mutualiste entre deux espèces. Nous étudions ce modèle dans une limite de grande population. Nous donnons par ailleurs des résultats numériques et une analyse biologique détaillée des comportements obtenus autour de deux problématiques : la coévolution de niches spatiales et phénotypiques d'espèces en interaction mutualiste et les dynamiques d'invasions d'un espace homogène par des espèces mutualistes. Dans la deuxième partie de cette thèse, nous développons un modèle probabiliste pour étudier finement l'effet d'une préférence sexuelle sur la spéciation. La population est ici structurée sur deux patchs et les individus, caractérisés par un trait, sont écologiquement et démographiquement équivalents et se distinguent uniquement par leur préférence sexuelle: deux individus de même trait ont plus de chance de se reproduire que deux individus de traits distincts. Nous montrons qu'en l'absence de toute autre différence écologique, la préférence sexuelle mène à un isolement reproductif entre les deux patchs
We study the spatial and evolutionary dynamics of a population by using probabilistic and deterministic tools. In the first part of this thesis, we are concerned with the influence of a heterogeneous environment on the evolution of species. The population is modeled by an individual-based process with some interactions and which describes the birth, the death, the mutation and the spatial diffusion of each individual. The rates of those events depend on the characteristics of the individuals : their phenotypic trait and their spatial location. First, we study the system of partial differential equations that describes the spatial and demographic dynamics of a population composed of two traits in a large population limit. We characterize precisely the conditions of extinction and long time survival for this population. Secondly, we study the initial individual-based model under two asymptotic: large population and rare mutations such as demographic and mutational timescales are separated. Thus, when a mutant appears, the resident population has reached its demographic balance. We characterize the survival probability of the population descended from this mutant. Then, by studyingthe process in the mutational scale, we prove that the microscopic process converges to a jump process which describes the successive fixations of the most advantaged traits and the spatial distribution of populations carrying these traits. We then extend the model to introduce mutualistic interactions between two species. We study this model in a limit of large population. We also give numerical results and a detailed biological behavior analysis around two issues: the co-evolution of phenotypic and spatial niches of mutualistic species and the invasion dynamics of a homogeneous space by these species. In the second part of this thesis, we develop a probabilistic model to study the effect of the sexual preference on the speciation. Here, the population is structured on two patches and the individuals, characterized by a trait, are ecologically and demographically similar and differ only in their sexual preferences: two individuals of the same trait are more likely to reproduce than two individuals of distinct traits. We show that in the absence of any other ecological differences, the sexual preferences lead to reproductive isolation between the two patches

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De, Grande Fernando Rafael [UNESP]. « O conteúdo orgânico do sedimento influencia na distribuição intraespecífica de caranguejos-chama-maré ». Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138857.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Caranguejos do gênero Uca são importantes organismos da macrafauna bentônica em ambientes estuarinos. Varias espécies coabitam bancos lodosos e arenos da zona-do-entre-marés onde eles se alimentam de micro-organismos ou detritos do sedimento. As espécies apresentam zonas relativamente distintas e o estabelecimento dessas zonas é causado por fatores bióticos e abióticos. Dentre estes fatores a matéria orgânica do sedimento é um dos mais importantes. Desta forma, nós testamos o efeito da matéria orgânica do sedimento sobre a distribuição intraespecífica de U. thayeri e U. uruguayensis em seus respectivos habitats. O teor de matéria orgânica do sedimento, a densidade e o tamanho dos caranguejos foi observado em quadrados amostrais dispostos ao longo de transectos perpendiculares a linha da água. Em laboratório foi utilizado microcosmos com e sem escolha para testarmos a preferência dos caranguejos por sedimento com alta e baixa matéria orgânica. Nós também avaliamos a alimentação (número de pinçadas no sedimento) e o número de tocas escavadas em cada tipo de sedimento para duas categorias de tamanho de U. uruguayensis (grandes e pequenos). Ambas as espécies apresentaram uma relação negativa entre o tamanho dos caranguejos e o teor de matéria orgânica do sedimento. Este padrão não é causado pelo comportamento de preferência dos caranguejos por sedimentos com diferentes quantidades de matéria orgânica. Além disso, ambas os tamanhos de caranguejos comem menos em sedimentos com alta quantidade de matéria orgânica. E, os caranguejos pequenos comem mais do que os grandes, independentemente do tipo de sedimento. Nossos resultados sugerem qua a matéria orgânica do sedimento indica a quantidade de comida disponível para os caranguejos chama-maré. Devido a isso, áreas com maior quantidade de matéria orgânica suportam populações mais densas. Em um banco monoespecífico os caranguejos menores ocupam a nível inferior da zona-do-entre-marés onde há mais matéria orgânica. Caranguejos grandes são predominantes na região superior da zona do entre marés.
Crabs of the genus Uca are important benthic macrofauna in estuarine environments. Several Uca species coexist on intertidal mud- and sand-flats where they feed on microorganisms or sediment debris. Species have relatively distinct zones, and zone establishment is based on biotic and abiotic factors. Sediment organic matter is thought to be one of the most important zoning factors. We tested the effects of organic matter content on intra-specific distribution of U. thayeri and U. uruguayensis in their habitats. Organic matter content, crab density, and size frequency were observed in quadrates at each meter along intertidal transects (length of transect). In laboratory microcosms with- and without-options were used to test any preference of crabs for high- or low-organic content sediment. We also assessed feeding (scoops into sediment) and the number of burrows dug into each sediment for two categories of U. uruguayensis (large and small individuals). Both species showed a negative relationship between crab size and organic content, and both showed higher densities in field sites with more organic matter. This pattern was not due to a preference behavior of crabs for sediments that vary only by organic matter. Both sizes of crabs fed less frequently in sediments with high organic content. Small crabs feed more than large crabs regardless of the sediment type. Our results indicate that food organic matter influences the amount of food available to fiddler crabs. Because of this, sites with high organic content support populations at higher densities. In a mono specific patch, small crabs occupy the lower level of the intertidal zone, which contains more organic matter. Large crabs are predominant in the intertidal zone high level.
FAPEPS: 2015/00456-7

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Coyle, Jayme. « The Influence of Oxygen Tension and Glycolytic and Citric Acid Cycle Substrates in Acrolein-induced Cellular Injury in the Differentiated H9c2 Cardiac Cell Model ». Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6487.

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Most in vitro systems employ the standard cell culture maintenance conditions of 95 % air with 5 % CO2 to balance medium pH, which translates to culture oxygen tensions of approximately 20 % - above the typical ≤ 6 % found in most tissues. The current investigation, therefore, aims to characterize the effect of maintenance and toxicant exposure with a particular focus on the α,β-unsaturated aldehyde, acrolein, in the presence of physiologically relevant oxygen tension using a differentiated H9c2 cardiomyoblast subclone. H9c2 cells were maintained separately in 20.1 and 5 % oxygen, after which cells were differentiated for five days, and then exposed to acrolein in media containing varying concentrations of tricarboxylic acid and glycolytic substrates. Cells were then assessed for viability and metabolism via the MTT conversion assay. H9c2 cells were assessed for mechanistic elucidation to characterize contributors to cellular death, including mitochondrial membrane potential (ΔΨm) reductions (JC-1), intracellular calcium influx (Fluo-4), and PARP activation. Exposure to acrolein in differing oxygen tensions revealed that standard culture cells are particularly sensitive to acrolein, but cells cultured in 5 % oxygen, depending on the medium pyruvate concentration, can be rescued significantly. Further, reductions in ΔΨm were reversed by co-exposure of 5-10 mM EGTA for both culture conditions, while intracellular calcium transients were noted only for standard cultures. The results demonstrate significant metabolic reprogramming which desensitizes differentiated H9c2 to acrolein-induced cytotoxicity. Further, PARP and extracellular calcium contribute to the fate of these cells exposed to acrolein, though clotrimazole-associated TRPM2 channels may not be significantly involved. Conclusively, significant alteration of toxicogenic response was noted in this cell line when cultured under physiologically relevant conditions, and may have a substantial impact on the reliability and predictive power and interpretive application of in vitro-based toxicity models cultured under standard culture conditions, depending on the parent tissue.

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Kolm, Niclas. « Influence of Mate Quality on Reproductive Decisions in a Fish with Paternal Care ». Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3562.

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Othman, Daryan Jalal. « The influence of adhesive curing temperature upon the performance of FRP strengthened steel structures at ambient and elevated temperatures ». Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29646.

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The structural adhesives widely used in structural strengthening applications are thermoset ambient cure adhesive polymers. At ambient temperatures, these polymers are in a relatively hard and inflexible state. At higher temperatures, the material becomes soft and flexible. The region where the molecular mobility changes dramatically is known as the glass transition temperature Tg and often is presented as a single value. Epoxy polymers exhibit a significant reduction in mechanical properties near glass transition temperature Tg when they are exposed to elevated temperatures. Glass transition temperature Tg is used to characterise the change in epoxy adhesive properties with changing temperature. The mechanical properties of epoxies tend to improve with curing temperature. This is because the crosslink density between the adhesive molecular structures increases during the curing process consequently the Tg improves. The aims of this work are first to demonstrate the importance of curing temperature. Second, to investigate the influence of glass transition temperature !! improvement on the performance of EB-FRP strengthened steel structures in flexure at ambient and elevated temperatures. Third, to compare analytical results with experimental results from the flexure tests results. Finally, to compare the current design guideline recommendations with the flexure tests results. The most commonly used methods to evaluate Tg Dynamic Mechanical Analysis (DMA) and Differential Scanning Calorimetry (DSC) were used to study Tg. Two off-shelf structural adhesives were investigated to understand their property variation with temperature. Epoxy coupons were cured at different elevated temperature and humidity environments up to 28 days. A combination of two extreme relative humidity of 0 and 100% and variable curing temperatures between 15 to 80°C were considered. From a test matrix of 300 DMA and over 250 DSC coupons these conclusions were drawn. First, ambient cured thermosets have a linear relationship between Tg and curing temperature, but Tg is reduced if a certain temperature is reached. Second, a fully cured adhesive requires heating treatment. Without a curing regime, designed Tg may never be achieved. Finally, curing time is crucial at the low curing temperatures while it is less significant at the higher curing temperature. The results of Tg investigation were used to select appropriate curing temperature that the adhesives resistance to temperature can be maximised without damaging the mechanical properties. The study helps designs to understand and assess the behaviour of these two adhesives when they are exposed to extreme temperatures. The study increases the awareness that a fully cured adhesive may never be achieved at ambient or low temperatures. It is important to find the mechanical properties and Tg when the coupons are exposed to the same curing temperature. To investigate the influence of glass transition temperature Tg improvement on the performance of EB-FRP strengthened steel structures in flexure at ambient and elevated temperature, nine three metre length beams were designed to behave as a concrete-steel composite bridge deck. The beams were tested in four-point bending. Lap shear, DMA test, and pull-off adhesion samples were prepared and cured at the same conditions and tested at ambient temperature. Six beams were tested under only mechanically loading at ambient temperature, including the control specimen. Five beams were tested at ambient temperature to show the effects of adhesive curing on FRP strengthened sections. A significant increase of load capacity of the adhesive joints was achieved due to the curing of the joints at elevated temperature. The failure occurred was in the same manner. An increase in the load capacity was observed with increasing curing temperature. An increase of approximately 25% was noticed in the ultimate load capacity of the specimens cured at 50°C compared to the specimens cured at 30°C. The load capacity of lap-shear specimens cured at 50°C was 28% higher than the specimens cured at 30°C. Three specimens were tested under mechanical and thermal loading. A bespoke thermal chamber was designed and fabricated to apply a controlled thermal loading. The beams were loaded mechanically up to 350kN, first. The temperature of the specimens was then increased at a rate of 0.8°C/min. The sustained load 350kN remained constant during the heating phase. Digital Image Correlation (DIC) technique was used to detect the slippage of the tip of the FRP plates. The only specimen cured at 30°C showed relatively poor performance compared to the two specimens cured at 50°C. The plate ends started to slip when the adhesive storage modulus from the DMA runs reduced approximately by 15 and 18% for the beams cured at 30 and 50°C respectively. Pull-off adhesion tests confirmed that adequate surface preparation of over 25 MPa was achieved The flexural model for the composite steel section represented to predicate load-deflection behaviour of the specimens using semi-experimental constitutive material law. The model successfully predicts the load-deflection behaviour of specimens, considering the strain hardening contribution. A bond stress analysis is also presented, which counts for the effect of FRP plate moment effect. The experimental and theoretical FRP plate slippage assuming only adhesive degradation with temperature are compared. The analytical bond models cannot predict the experimental failure because the linear elastic material properties were assumed and the failure was adhesion.

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