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Krasuska, Marta. "Response shift and dentine hypersensitivity." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/8310/.
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Objectives: Response shift refers to the changes in the meaning of self-evaluation of quality of life (QoL) as a result of changes in internal standards of measurement (recalibration), changes in relative importance of component domains of quality of life (reprioritisation) or redefinitions of QoL (reconceptualisation). Response shift can therefore undermine the comparison of QoL within individuals over time and between individuals, for example when assessing treatment effects. The aim of this research was to investigate response shift in people with dentine hypersensitivity (DH). Methods: Two studies were conducted. A quantitative study investigated recalibration and its influence on the assessment of treatment effect in 114 participants of an 8-week randomised controlled trial of mouthwashes for DH. Two approaches: the THEN TEST and a novel approach; the IDEALS were incorporated into the Dentine Hypersensitivity Experience Questionnaire (DHEQ) to assess recalibration. A qualitative study longitudinally explored response shift and its underlying psychosocial mechanisms in 20 individuals with self-reported DH. Two semi-structured interviews were conducted 6-9 months apart and Framework analysis was used to analyse the transcripts. Results: The quantitative study found recalibration in the treatment groups. The THEN TEST indicated a downward shift in participants’ internal standards of measurement whereas the IDEALS suggested a shift upwards. Individuals shifted upwards, downwards and not at all. Additionally, recalibration was similar in the treatment and placebo groups. Accounting for recalibration reduced the apparent treatment effect in all groups. In the qualitative study two main findings emerged. First, the study described adaptation to DH and its influence on the assessment of oral health related quality of life (OHQoL). Second, a modified model of response shift emerged that distinguished between the influence of adaptation and measurement error on the assessment of QoL. Conclusion: The two studies described response shift, its psychosocial determinants and influence on the assessment of treatment effects in people with DH as an example of a mild health condition. Moreover, the two studies challenged the current conceptualisation and the dominant approach to the measurement of the phenomenon. A modified model of response shift was proposed and a novel way of its assessment, the IDEALS was initially validated.
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Beeken, Rebecca J. "Health-related quality of life and response shift." Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521916.
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Guilleux, Alice. "Méthodes pour l'identification et la prise en compte de l'évolution de la perception des patients vis-à-vis de leur état de santé (response shift) au niveau de l'item dans les études longitudinales." Thesis, Nantes, 2016. http://www.theses.fr/2016NANT1015.
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En santé, le besoin de quantifier des phénomènes subjectifs a émergé au cours du dernier siècle avec par exemple, l'évaluation de la qualité de vie (QdV), de la fatigue ou de l'anxiété. L'intérêt croissant face à ces mesures de santé perçue appelées "Patient-Reported Outcomes" (PRO) apparaît notamment dans les maladies chroniques. Afin de pouvoir analyser l'évolution de la QdV des patients ou d'autres types de PRO au fil du temps, des données longitudinales sont collectées.Ces données issues de PRO sont difficiles à appréhender car les patients peuvent percevoir et interpréter différemment les questions qui leur sont posées au cours du temps selon l’évolution de leur maladie, en termes de signification, priorités et retentissement sur leur vie personnelle. Ce phénomène, appelé « response shift » (RS), est souvent lié à la façon dont les patients s’adaptent à leur maladie. En présence de RS, les évolutions observées des patients peuvent ne pas refléter correctement les véritables changements ressentis par ceux-ci. L’objectif de ce travail porte sur le développement et l’évaluation de deux approches l’une, basée sur les modèles à équations structurelles (SEM) et l’autre, sur la théorie de réponse à l’item (IRT), avec l’originalité de travailler au niveau de l’item. Ces méthodes permettent la détection et l'estimation du RS ainsi que sa prise en compte lors d’analyses.Les performances des approches ont été évaluées en les appliquant sur des données réelles mais également au moyen d'études de simulations. Les résultats obtenus grâce aux simulations permettent de mieux identifier quelle approche méthodologique adopter selon les contextes. Les avantages et inconvénients de l'utilisation de chacune des méthodes, sont soulignés et des recommandations ont été proposéesDuring the last century, many studies in health attempt to measure important characteristics, such as Health Related Quality of Life (QoL) using Patient-reported outcomes (PRO). QoL and other perceived health measures (pain, fatigue, etc.) are increasingly used in chronic diseases. In order to analyse the evolution of patients’ QoL or other types of PRO over time, longitudinal data are collected.These PRO data are difficult to interpret due to the patients’ changing in the standards, values, or conceptualization of what the PRO is intended to measure (eg: QoL). This phenomenon is referred to as “response shift” (RS) and is often linked to the way the patients might adapt or cope with their disease experience. As a consequence of RS, observed patient’s evolutions may thus not properly reflect true perceived health changes.The objective of this work is to develop and assess two approaches at item level, one, based on structural equation modelling (SEM) and other, on item response theory (IRT). These statistical approaches are currently used for RS analysis on PRO data. Both the identification of RS occurrence and its appropriate adjustment in the analyses of longitudinal PRO data are studied.The performance of IRT and SEM were assessed by applying them on real data and through simulations studies. The results obtained in the simulation allow choosing which methodological approach should be applied according to the context.The pros and cons of using one method or another as well as the potential of using both of them as complementary analyses providing different insights into the field of response shift are be underlined
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Ahmed, Sara 1974. "Response shift and health-related quality of life post-stroke." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84979.
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There is growing consensus that health-related quality of life (HRQL) outcomes are important for the allocation of scarce medical resources and for facilitating clinical decision-making. However, because most instruments of HRQL are self-report measures inappropriate conclusions may be drawn from studies that assess changes in HRQL over time or between groups. If the individuals evaluating themselves experience a response shift (defined as changes in their internalized standard of evaluating their level of functioning, in their values, or in their conceptualization of the target construct), then measures taken over time or between groups are no longer comparable. To date, response shift has not been formally assessed in the stroke population, and only to a limited extent in the HRQL field. The global objective of this thesis was to examine how the experience of recovering from a stroke modifies people's perception of their health-related quality of life (HRQL), and the extent to which response shift occurs during the first six months post-stroke.The first study used structural equation modeling for data from a prospective cohort to evaluate response shift by examining changes in a theoretical model of HRQL based on the measurement model of the Medical Outcome Study 36-Item Short Form Health Survey (SF-36). This study found no evidence of reconceptualization and changes in internal standards over time, but suggested that if response shift does occur with stroke it is likely to be mediated by the event itself and not the recovery process. Two subsequent studies evaluated response shift using the then test (a retrospective assessment of HRQL) and an individualized measure of HRQL. The data collection for these studies was incorporated into a randomized controlled trial. The results from the then test provided support for the occurrence of response shift among persons with stroke with no such effect in a control group. Changes on the individualized measure of HRQL showed that individuals with stroke experienced a reconceptualization and a change in values between 6 and 24-weeks post-stroke. A final comparison of the three techniques evaluated in this thesis provided the basis for proposed guidelines for future assessments of change in HRQL based on the comparative feasibility and validity of the methods. To date, there is evidence to show that individuals undergoing changes in physical health experience changes in internal standards of health and values. If response shift is not measured and accounted for, inappropriate conclusions regarding the impact of a disease such as stroke or the efficacy of a treatment intervention may go unnoticed.
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Kennedy, Ian. "Magneto-acoustic response of a 2D carrier system." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285634.
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Carlson, Robin. "Clinical Significance of Response Shift in a Spine Interventional Clinical Trial." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/231.
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The effectiveness of treatments for degenerative spine conditions, where the primary symptom is back pain, is typically determined using patient-reported quality of life (QoL) measures. However, patients may adjust their internal standards when scoring QoL based on factors other than their health. This response shift phenomenon could confound the interpretation of study data and impact effectiveness conclusions. In the current study, response shift was examined using structural equation modeling (SEM) and previously collected clinical trial data comparing 2 minimally invasive medical devices in lumbar spinal stenosis patients through 1 year postintervention. In subject QoL results, reprioritization shift between 3 months and 12 months that could confound standard analysis was identified. Treatment group did not influence response shift identified at 12 months. SEM provided an effective and practical tool for clinical investigators to assess response shift in available clinical study data. As response shift could lead to invalid conclusions when QoL measures are analyzed, clinical investigators should include response shift assessment in the design of clinical trials. This research into how response shift phenomenon can impact clinical trial results improves the ability of clinical investigators to interpret clinical trial data, potentially preventing erroneous conclusions. This research may also assist researchers and government regulators in the identification and reimbursement of beneficial, cost-effective medical treatments for patients worldwide. For clinical research designers, this study demonstrates a practical application of response shift assessment.
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Daniels, Katherine Nelson. "Response Shift Bias| An Examination of Measuerment Invariance in Self-reported Change." Thesis, Western Michigan University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10904580.
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Barisa, Marta. "Human peripheral γδT cell phenotypic and functional shift in response to stimulation with E.coli." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/10038983/.
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It is known that γδT cells provide immune-surveillance and host defense against infection and cancer. Our understanding of γδT cell functionality and antimicrobial immunity, however, remains poor. Limited data suggests that γδT cells can phagocytose particles and act as professional antigen-presenting cells (pAPCs). In order to examine γδT cell bacterial interactions, an ex vivo co-culture model of human peripheral blood mononuclear cell (PBMC) responses to Escherichia coli was employed. Following PBMC stimulation with E.coli, Vγ9Vδ2 cells underwent rapid T cell receptor (TCR)-dependent proliferation and functional transition from cytotoxic, inflammatory cytokine immunity, to cell expansion with diminished cytokine but increased costimulatory molecule expression, and capacity for professional phagocytosis. Phagocytosis was augmented by IgG opsonization, and inhibited by TCR-blockade, suggesting a licensing interaction involving the TCR and FcγR. Vγ9Vδ2 cells displayed potent cytotoxicity through TCR-dependent and independent mechanisms. Vγ9Vδ2 cell cytokine responses and cytotoxicity further presented with variable sensitivity to blocking of host butyrophilin 3A (BTN3A), in response to both, self and non-self, stimuli. We conclude that i) Vγ9Vδ2 T cells transition from early inflammatory cytotoxic killers to myeloid-like pAPCs in response to infectious stimuli, and that ii) Vγ9Vδ2 T cell recognition of targets is predominantly governed by TCR recognition of self stress markers in a BTN3A-dependent manner.
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Chen, Jie. "Energy Expenditure, Heart Rate, Work Pace, and Their Associations with Perceived Workload among Female Hospital Nurses Working 12-hour Day Shift." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1244645978.
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Gebro, Per. "National scale impact of the Stockholm Royal Seaport project : Demand response and load-shift for Swedish apartment customers." Thesis, KTH, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-120118.
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The Swedish electrical power system faces many challenges. Stricter environmental and economic demands require a more efficient use of both the transmission and distribution grids as well as the production capabilities. Since the Swedish national demand of electricity is fluctuating, the system has always been dimensioned to meet the periods of high demand, resulting in a low utilization of the system. To meet these challenges, the concept of a “Smart Grid” has been phrased. One of the most important goals of a Smart Grid is to enable end-consumers to participate more actively in the energy market. One way to do this is through “load-shifting” where consumption (or loads) are moved from hours of high demand (peak hours) to hours of low demand (off-peak hours). Load-shifting is a part of a set of intentional consumption modifications denoted “Demand Response” (DR) and is deemed to be one of the most important tools of the Smart Grid. In Sweden, a Smart Grid project called the Stockholm Royal Seaport (SRS) project is currently taking place. The project have phrased a hypotheses regarding load-shifting called the “Active customer” scenario, in which a customer load-shifts 5-15 % of his electricity consumption. To facilitate this scenario, the SRS project uses an end-consumer price model for electricity, called the SRS price model, as well as technological and market solutions not yet available on a national scale. This study investigates what impact the results from the SRS pilot project might have if implemented for private apartment end-consumers on a Swedish national scale. The study is divided into three parts. The first part investigates the challenges of a national scale implementation of private apartment end-consumer DR and the SRS price model. The second part investigates what the impact would be if the entire Swedish private apartment end-consumer sector where to act in accordance with the Active customer scenario. The third part consists of a sensitivity analysis. Four challenges for a national private apartment end-consumer load-shift implementation have been elicited. They are; the lack of easily moveable loads in a foreseeable future, the heterogeneous cost of distribution, the suggested price models low peak to off-peak price ratio and the comparatively small cost of electricity of the private apartment end-consumers. The SRS price model is deemed to give a clear economic incentive for load-shift of private apartment end-consumer without electric heating. However, the incentive might be considered too weak with yearly savings of 48-165 SEK for a 15 % load-shift, depending on apartment consumption. This corresponds to yearly savings of 124 to 429 million SEK for the entire customer segment. These challenges are deemed to be of a non-technical character, but rather of a marketing and communication nature. The impact of a fully implemented national private apartment end-consumer load-shift in accordance with the Active customer scenario and the SRS price model is deemed to be beneficial from an overall power system point of view. However, the impact on the private apartment end-consumer national demand is small in comparison with other plausible system developments, such as energy demand reductions due to more efficient lighting solutions. The sensitivity analysis of private apartment end-consumer cost savings when acting in accordance with the Active customer scenario indicates that the percentage savings may increase in the future when considering more volatile prices for electric energy or the implementation of a time differentiated energy tax.
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Robling, Michael. "Measuring change in patient quality of life over time : an evaluation of scale responsiveness and patient response shift." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/54272/.
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Measuring change in quality of life is increasingly central to health services and clinical research evaluation. This requires instruments that are responsive to change, and that the construct being assessed is stable. I have, therefore, addressed two methodological themes: scale responsiveness and instability of the underlying quality of life construct - response shift. Responsiveness theme: I evaluated performance characteristics of a commonly reported effect size statistic, the standardised response mean (SRM). Computer simulations modelled the impact of varying computational method and distributional characteristics upon bias of estimated effect size compared to underlying true value. The studies provide evidence and reassurance that the SRM exhibits little bias when sample size, mean underlying effect size and shape of underlying distribution are varied. However, alternate approaches to handling negative values can produce markedly different effect sizes, making comparison across studies that use different methods problematic. Furthermore, parametric SRMs calculated from lognormal data may provide a greatly inflated estimate of effect size. Response shift theme: I interviewed patients at different stages of clinical management for knee injury twice over six months. A multi-method approach incorporating the individualised SEIQoL-DW measure and a retrospective pretest-posttest using EQ-5D identified evidence of re-calibration, re-prioritisation and re-conceptualisation response shift. An empirically based typology of changes was developed drawn from existing response shift theory, but which further distinguishes subtler forms of change. The studies provide evidence that re-prioritisation and re-conceptualisation may be different levels of the same process. Furthermore, mechanisms producing response shift were identified, in particular, the interaction between level of satisfaction with quality of life domain and its perceived importance. Additional approaches to studying response shift using group level comparison of SEIQoL data were critically evaluated. The thesis extends the methods for identifying, assessing and conceptualising response shift changes whilst also exploring mechanisms which may explain these changes.
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Brodén, Daniel. "Analysis of Demand Response Solutions for Congestion Management in Distribution Networks." Thesis, KTH, Industriella informations- och styrsystem, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-138575.
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According to the 20-20-20 targets set by the European Union, 50 percent of the Swedish electricity share is to be provided by renewable energy sources by 2020. The Smart Grid Gotland (SGG) project has emerged as a response to this target. The project aims at demonstrating a proof of concept on how smart grid solutions can be used to integrate large quantities of renewable energy sources in an existing network. The outcomes of the project are intended to pave the way for future renewable energy integration projects in Sweden. The Thesis focuses on one of the technical objectives of the SGG project, i.e. to increase the hosting capacity of wind power on Gotland from 195 MW to 200 MW by using Demand-Response (DR) from households and industries. DR consist of shifting peak-loads to peakproduction hours. The integration of additional wind power causes a risk of exceeding the transmission capacity of the power export cable between Gotland and the Swedish mainland. The approach considered for this Thesis is to use an Ancillary Service (AS) toolbox scheme based on multi-agent systems. The AS toolbox consist of flexibility tools such as DR on long-term, short-term, a battery energy storage system and a wind curtailment scheme. The DR activity includes space heating and domestic hot water consumption from detached houses on Gotland. The simulation results indicate that 1900 household participants are sufficient to balance the additional 5 MW for worst case scenarios. Furthermore, it is shown that the DR participation from industries contributes in some cases to a reduction of 700 household participants. The findings helped conclude that using an AS toolbox solution on Gotland is fully possible from a technical perspective. However, barriers that stand against its realisation are of economical nature and need to be investigated in future studies.
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Blair, Hannah. "Subjective evaluation of quality of life after brain injury : measuring quality of life and the impact of response shift." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/21458.
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Introduction: After a brain injury there are often long term consequences impacting on QoL. However, this is a complex issue influenced by many factors. As someone recovers and adjusts it is likely that the way in which they evaluate QoL will also change. The theory of response shift suggests people will change the way they evaluate QoL in the face of changes in their life. The aim of this thesis is to investigate what influences a QoL judgement; examining the possibility of response shift. Methods: Quantitative and qualitative methods were used in 4 studies. These were a cross-sectional design utilising an individualised QoL measure (SEIQoL-DW); a longitudinal study utilising a ‘then-test’ approach; a cross-sectional questionnaire study; and a qualitative study using Interpretative Phenomenological Analysis. Study 1 (Ch.3) Results: Correlations between the QoL measures confirm the validity of the SEIQoL-DW; however, correlations were generally stronger for the simpler Hadorn Scale. There was little overall change in mean QoL when current and retrospective judgements were compared. There was evidence for a change in what areas of life were considered most important to QoL following injury. Study 2 (Ch.4) Results: Improvements in reported QoL between baseline and follow-up were small. A then-test indicates that any effect of response shift is small, and non-significant in the current research. There was also little evidence for reprioritisation or re-conceptualisation. Examination of other factors associated with QoL suggest that brain-injury specific factors (BIGI, RBANS) play a role in predicting QoL. Study 3 (Ch.5) Results: QoL was reported as worse post-injury on both Hadorn’s scale and the QOLIBRI-OS; a difference that was more pronounced on the QOLIBRI-OS. Differences were also reported in the importance of different areas of functioning. Change in QoL as measured by the QOLIBRI-OS was significantly influenced by disability as measured by the GOSE, emotional and informational support, and upwards social comparison. Optimism as measured by the LOT, but not upwards social comparison was a significant predictor of change on Hadorn’s scale; GOSE and emotional and informational support remain significant predictors. The GOSE, emotional and informational support, emotional coping styles and optimism were significant predictors of current QoL on the QOLIBRI-OS; and emotional and informational support and optimism were significant predictors of QoL on Hadorn’s scale. Little evidence was found to suggest that the factors proposed in Sprangers and Schwartz’s (1999) model of response shift have predicted relationships with QoL. Two candidate variables were studied: optimism and social support. However neither showed the predicted pattern of relationships. Nonetheless the study supports previous work indicating an influence of optimism and social support on QoL, and indicates that these warrant further study. There were systematic difference between current and retrospective ratings of importance of domains. The level of importance given to the areas of life defined by the QOLIBRI-OS is higher after injury than before, with the exception of “personal and social life” for which there is no significant difference. The areas of life chosen to reflect that which is measured by the GOSE (“work”, “close relationships”, and “social and leisure activities”) are rated as less important with the exception of “close relationships”. These findings provide further support for the idea that QoL domains are re-evaluated after brain injury. Study 4: This was an in depth qualitative investigation of the experience of recovery and adjustment following TBI. Semi-structured interviews and Interpretative Phenomenological Analysis (IPA) were used. Interviews were conducted with 4 men who were 3, 7, 12, and 18 years post injury. Main Outcome and Results: Themes emerging from the analysis were ‘Change: In Self and World’; ‘Reaching a point of realisation’; ‘Support’; ‘Adjusting to change/Coping with day to day life’; and ‘Participation, Goals and Focus’. These themes cover how participants felt both they and their lives had changed as a consequence of their injury; ways they went about coping and adjusting to changes; the importance of support; and the significance of social integration and participation in feeling satisfied with life. Summary and Conclusions: These studies provide evidence for response shift in different ways. There is little evidence for recalibration but there is some indication that reprioritization or reconceptualization may take place. Changes in how important different areas of life are before and after injury suggest that participants are changing the way they view and make evaluations of QoL. Factors identified as being important to QoL judgements were disability, social support (emotional and informational support identified in the questionnaire study and support in the IPA), upwards social comparison, and optimism. The IPA study suggests that functional outcome and participation are important after TBI; while also identifying ways of coping and providing an insight into the experience of recovery from brain injury. The different QoL measures used provides both evidence for their validity, but also evidence for the different conceptualisations of QoL that are measured by different instruments. The findings have implications both for understanding the QoL of the individual and for research on QoL after TBI.
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Ryckebusch, Gaëlle. "Analysis of Demand-Response Participation Strategies for Congestion Management in an Island Distribution Network." Thesis, KTH, Industriella informations- och styrsystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169220.
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The Master Thesis is part of the Smart Grid Gotlandproject. This project aims at implementing smart grid solutionson the island of Gotland in order to be able to efficientlyintegrate large quantities of renewable energy production.In situations of high wind power production and lowconsumption, energy export problems may occur betweenGotland and the mainland. A novel approach to manageanticipated congestions, compared to traditional gridreinforcements, consists of using flexibility from demandresponse(DR) resources. However, such an approach presentschallenges as it requires both technical and economic considerations.This Master Thesis proposes and analyses twomarket-based strategies applied to detached houses for dayaheadcongestion management. The strategies are implementedin an Ancillary Service toolbox developed in theMATLAB programming environment.The first strategy involves using a dynamic network tariffwhile the second uses spot price optimization. Simulationsare performed for seasonal worst-case congestion scenarioswhile satisfying comfort and economic constraints ofthe DR participants. A sensitivity analysis is carried out toassess the impact of different spot price profiles and windpower production prognosis errors on the results.Results show that congestions are managed with a feasiblenumber of participants, but that their savings are negligiblefor both strategies (between 2 and 40 SEK/participant).Moreover, using a dynamic network tariff strategy impliesa DSO cost in the range of 1700-89000 SEK. These resultsapply for a 3-days congestion period, which is estimated tooccur 5-6 times a year if the maximum hosting capacity isincreased by 5 MW.To conclude, an AS toolbox with economic constraintsis feasible for Gotland conditions with a reasonable numberof DR participants. However, the simple cost-benefitanalysis that was carried out showed that the AS toolboxapproach was still much more costly than traditional gridreinforcement.
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Rees, Jonathan. "Measurement of response shift in quality of life and symptom assessment in patients with advanced prostate cancer and their partners." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398668.
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Boucekine, Mohamed. "Caractérisation de l'effet response shift par l'approche des forêts aléatoires : application à la sclérose en plaques et à la schizophrénie." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM5062.
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Evaluer la qualité de vie (QV) a pris une importance croissante dans le domaine de la santé, tout particulièrement pour les maladies graves tels que les cancers. Cependant l’analyse des données de QV demeure complexe et reste peu utilisée pour changer les standards de prise en charge des patients. Une des raisons est que les patients pourraient exprimer un effet « response shift » (changement de réponse) au cours de la maladie et par conséquent biaiser les résultats en sur- ou sous estimant l’effet traitement mesurer par le différentiel de QV. En effet lorsque l’évolution de la QV est étudiée, on fait souvent l’hypothèse que la perception qu’ont les patients du concept étudié ne va pas se modifier au cours du temps. Or les patients font face à une maladie et à des traitements. L’impact que peuvent avoir la maladie et les traitements sur la vie du patient va généralement l’amener à s’adapter et modifier sa perception du concept étudié. Ainsi l’occurrence potentielle d’un effet « Response Shift » est une des problématiques à appréhender pour distinguer ce qui relève d’un « vrai » changement de QV et de ce qui est de l’adaptationTo asses Quality Of Life, patients are often asked to evaluate their well-being using a self-report instrument to document patient-reported outcome (PROs) measures. The data are often collected on multiple domains, such as physical function, social health and emotional health. However, longitudinal PROs, which are collected at multiple occasions from the same individual, may be affected by adaptation or "response shift" effects and may lead to under- or overestimation of the treatment effects. Response shift is the phenomenon by which an individual's self-evaluation of a construct changes due to change in internal standards of measurement (recalibration), a change in value or priorities (reprioritization), or a personal redefinition of the target construct (reconceptualisation). If the response shift is present in the data, the interpretation of change is altered and conventional difference between post-test and pre-test may not be able to detect true change in PROs measures. The aim of the work is to propose an innovative method, based on random forest method, to highlight response shift effect
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Merighi, Massimo. "Molecular biology and biochemistry of regulation of Hrp/type III secretion genes in the corn pathogen Pantoea stewartii pv. stewartii." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1069854564.
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Thesis (Ph. D.)--Ohio State University, 2004.Document formatted into pages; contains xxxiii, 421 p. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2005 Dec. 2.
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Vanier, Antoine. "The concept measurement, and integration of response shift phenomenon in Patient-Reported Outcomes data analyses : on certain methodological and statistical considerations." Thesis, Nantes, 2016. http://www.theses.fr/2016NANT1009/document.
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Les données rapportées par les patients sont maintenant fréquemment utilisées en recherche biomédicale. Ces instruments permettent la mesure de concepts subjectifs tels que la qualité de vie, les niveaux d’anxiété, de douleur, de fatigue. L’interprétation d’une différence de score au cours du temps était basée sur l’hypothèse que le sens des concepts et échelles restai stable au cours du temps dans l’esprit des individus. Cette hypothèse semble aujourd’hui dépassée. L’auto-évaluation d’un concept est maintenant comprise comme contingente de la représentation subjective qu’à un sujet du dit concept, cette représentation pouvant changer au cours du temps, surtout après avoir vécu un évènement de santé : ce phénomène est connu comme le « response shift ». Depuis la fin des années 1990s, l’investigation de ce phénomène est devenue un sujet d’intérêt majeur en psychométrie. Si des développements ont vu le jour, ce sujet reste récent et donc accompagné de débats variés que ce soit sur le plan théorique ou méthodologique. Aussi, l’objectif général de cette thèse est d’investiguer certaines problématiques méthodologiques et statistiques liées au response shift. Ce manuscrit est composé de trois travaux principaux : un état de l’art et une synthèse des travaux conduits à un niveau international depuis que le response shift est étudié, une étude pilote des performances de la procédure d’Oort (une méthode populaire de détection de response shift) par simulations et un travail théorique sur les liens entre response shift et complexité sémantique des concepts mesurés et items utilisésPatient-Reported Outcomes are increasingly used in health-related research. These instruments allow the assessment of subjective concepts such as Health-Related Quality of Life, anxiety level, pain or fatigue. Initially, the interpretation of a difference in score over time was based on the assumption that the meaning of concepts and measurement scales remains stable in individuals’ minds over time. This assumption has been challenged. Indeed, the self-assessment of a concept is now understood as a contingency of the subjective meaning a subject has of this concept, which can change over time especially as a result of a salient medical event: the “response shift” phenomenon. Since the end of the 1990s, researches on response shift phenomenon has become of prime interest in the field of health-related research. If developments have been made, it is still a young field with various scientific debates on a theoretical, methodological and statistical level. Thus, the broad objective of this thesis is to investigate some methodological and statistical issues regarding response shift concept, detection and integration into PRO data analyses. The manuscript is composed of three main works: a state of the art and synthesis of the works conducted at an international level since response shift phenomenon is investigated, a pilot study investigating the statistical performances of the Oort’s Procedure (a popular method of response shift detection using Structural Equation Modeling) by simulations and a theoretical work about the links between response shift occurrence and semantic complexity of concepts measured and items used
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Ellis, Natalie. "Aquatic habitat shift assessment in a groundwater-fed semi-arid stream:an investigation into the response of Karoo hydroecology to system variability." Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/61882.
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From introduction: The subject of biological response to changes in aquatic habitat is one which has been well explored in many regions of the world. Examples include work in south east Spain by Mellado Diaz et al. (2008) and Oliva-Paterna et al. (2003), in western United States of America by Hauer and Lorang (2004), and in West Germany by Meyer et al. (2003). Similarly, a number of studies have been conducted in semi-arid regions, exploring elements such as erosion, climate, lithology and landscape formations (e.g. Boardman et al., 2013; Le Maitre et al., 2007; Meyer et al., 2003). However, apart from the study by Uys (1997), and Uys and O’Keeffe (1997), there is a noticeable lack of literature on aquatic habitat shifts in semi-arid stream systems, despite these systems being recognised for their high natural variability. This study provides a base-level approach to conducting habitat shift assessments in a semi-arid stream system and monitoring the hydroecological responses to system variability.
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Niiranen, Susa. "Multiple forces drive the Baltic Sea food web dynamics and its response to environmental change." Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-92541.
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Understanding the interaction of multiple drivers and their compounded effects on ecosystem dynamics is a key challenge for marine resource management. The Baltic Sea is one of the world’s seas most strongly impacted by effects from both human activities and climate. In the late 1980’s changes in climate in combination with intensive fishing initiated a reorganization of the Central Baltic Sea (CBS) food web resulting in the current sprat-dominated state. In the future, climate change is projected to cause drastic changes in hydrodynamic conditions of the world oceans in general, and the Baltic Sea in particular. In this thesis, CBS food web responses to the combined effects of fishing, nutrient loads and climate were tested for the past (1974-2006) and projected into the future (2010-2098). A new food web model for the CBS (BaltProWeb) was developed using extensive monitoring data across trophic levels. This model described the past food web dynamics well, and was hence also used for future (2010-2098) projections. Different ensemble modeling approaches were employed when testing the food web response to future scenarios. The results show that regardless the climate change, the management of nutrient loads and cod fishing are likely to determine the food web dynamics and trophic control mechanisms in the future Baltic Sea. Consequently, the variation in the food web projections was large, ranging from a strongly eutrophied and sprat-dominated to a cod-dominated CBS with eutrophication levels close to today’s values. The results also suggest a potential risk of abrupt ecosystem changes in the future CBS, particularly if the nutrient loads are not reduced. Finally, the studies illustrate the usefulness of the ensemble modeling approach, both from the perspective of ecosystem-based management as well as for studying the importance of different mechanisms in the ecosystem response.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: In press. Paper 5: Submitted.
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Foster, Garett C. "Faking is a FACT: Examining the Susceptibility of Intermediate Items to Misrepresentation." Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1487256025031404.
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Jelitte, Matthias [Verfasser], and Reinhold [Akademischer Betreuer] Jäger. "Untersuchung von Response-Shift-Einflüssen auf die Erfassung der gesundheitsbezogenen Lebensqualität bei Prostatakrebspatienten in der onkologischen Rehabilitation / Matthias Jelitte. Gutachter: Reinhold Jäger." Landau : Universitätsbibliothek Landau, 2010. http://d-nb.info/1009141015/34.
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Howard, Jennifer Sebert. "CLINICAL AND FUNCTIONAL ASSESSMENT FOLLOWING AUTOLOGOUS CHONDROCYTE IMPLANTATION TO THE KNEE: THE ROLE OF PATIENT REPORTED OUTCOMES, PERFORMANCE BASED ASSESSMENT, AND RESPONSE SHIFT." UKnowledge, 2011. http://uknowledge.uky.edu/rehabsci_etds/1.
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Autologous chondrocyte implantation (ACI) is a cell based therapy for the treatment of articular cartilage defects. Numerous studies have reported outcomes following ACI using a variety of patient reported outcomes (PROs), but no clear recommendations exist regarding which PRO is the most responsive to changes following ACI. Few studies have documented changes in performance based assessments (PBAs) following ACI. Response shift theory proposes that residual changes in self-report measures occur over time. Failing to account for response shift may result in over or under reporting of outcomes from which clinical decisions are made. The purposes of this dissertation were 1) review the literature concerning ACI outcomes to determine the responsiveness of PROs to changes in self-reported function following ACI, 2) evaluate the reliability of PBAs among ACI patients, 3) develop a descriptive timeline for the return of function 1 year following ACI using both PROs and PBAs, and 4) utilize PROs and PBAs to evaluate patients undergoing ACI for evidence of response shift.
All PRO and PBA measures were collected preoperatively and 3, 6, and 12 months postoperatively. A retrospective then-test PRO evaluation of function prior to surgery was completed at 6 and 12 months. Response shift was calculated by subtracting the original pre-test score from the then-test score.
A systematic review and meta-analyses of existing ACI outcome studies resulted in the recommendation of the International Knee Documentation Committee Subjective Knee Form (IKDC) and Lysholm Knee Scale as highly responsive PROs among ACI patients of varying activity levels. Despite significant increases in PRO scores as early as 6 months following ACI, improvement in PBAs at 12 months following ACI were limited to stride length, walking speed, and step-up force. Finally, no evidence of a group level effect for response shift was observed. These results support the validity of traditional pre-test/post-test research designs with no need to account for response shift when evaluating treatment effects of ACI on the group level. However, the Western Ontario and McMasters University Osteoarthritis Index (WOMAC) did show evidence of a measurable response shift on a patient by patient basis.
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Erler, Antje. "Bias in retrospective assessment of perceived dental treatment effects when using the Oral Health Impact Profile." Springer International Publishing AG, 2018. https://ul.qucosa.de/id/qucosa%3A35213.
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Abstract Purpose Aim of this exploratory study was to investigate whether a retrospective assessment of oral health-related quality of life (OHRQoL) using the Oral Health Impact Profile (OHIP) is susceptible to bias such as implicit theory of change and cognitive dissonance. Methods In this prospective clinical study, a sample of 126 adult patients (age 17–83 years, 49% women) requiring prosthodontic treatment was consecutively recruited. The OHRQoL was assessed using the 49-item OHIP at baseline and at follow-up. Additionally, patients were asked at followup to retrospectively rate their oral health status at baseline (retrospective pretest or then-test) and the change in oral health status using a global transition question. Furthermore, patients’ ratings of overall oral health and general health were used as validity criteria for the OHRQoL assessments.
Response shift was calculated as the difference between the initial and retrospective baseline assessments. Results Baseline and retrospective pretest did not differ substantially in terms of internal consistency and convergent validity. Response shift was more pronounced when patients perceived a large change in OHRQoL during treatment. Retrospective pretests were more highly correlated with the baseline than with the follow-up assessment. Conclusion Findings suggest that retrospective assessments of OHRQoL using the OHIP-49 are susceptible to bias. Cognitive dissonance is more likely to appear as a source of bias than implicit theory of change.:Inhaltsverzeichnis
1. Einführung in die Thematik…………………………………………………2
2. Formatierte Publikation……………………………………………………..11
3. Zusammenfassung…………………………………………………………. 19
4. Literaturverzeichnis……………………………………………………….... 24
5. Anlagen
5.1. Darstellung des eigenen Beitrags……………………………………. 27
5.2. Selbstständigkeitserklärung…………………………………………... 28
5.3. Lebenslauf……………………………………………………………… 29
5.4. Publikationen…………………………………………………………… 30
5.5. Danksagung……………………………………………………………. 31
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Craig, Stephen Bartholomew. "Implicit Theories and Beta Change in Longitudinal Evaluations of Training Effectiveness: An Investigation Using Item Response Theory." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/27627.
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Golembiewski, Billingsly, and Yeager (1976) conceptualized three distinct types of change that might result from development interventions, called alpha, beta, and gamma change. Recent research has found that beta and gamma change do occur as hypothesized, but the phenomena are somewhat infrequent and the precise conditions under which they occur have not been established. This study used confirmatory factor analysis and item response theory to identify gamma and beta change on a multidimensional, multisource managerial performance appraisal instrument and to examine relations among the change types, training program content, and raters' implicit theories of performance. Results suggested that coverage in training was a necessary but not sufficient condition for beta and gamma change to occur. Further, although gamma change was detected only in the trainee group, beta change was detected in self-ratings from trainees and in ratings collected from their superiors. Because trainees' superiors were involved in post-training follow-up, this finding was interpreted as a possible diffusion of treatments effect (Campbell & Stanley, 1963). Contrary to expectations, there were no interpretable relations between raters' implicit theories of performance and either of the change types. Perhaps relatedly, more implicit theory change was detected among individuals providing observer ratings than in the trainees themselves. The implications of these findings for future research on plural change were discussed.Ph. D.
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Buckley, Elan. "Change in the Structure of Soil Microbial Communities in Response to Waste Amendments." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/101499.
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Soil microbial communities are affected extensively by addition of amendments to their environment. Of particular concern is the addition of poultry litter, which contains a substantial C, energy, and nutrient supply, but also antibiotic resistance genes (ARG), antimicrobials, and a multitude of microbial species. This project seeks to primarily assess if there is a change in bacterial community structure in response to poultry litter amendments to pasture land across geographically independent land across northern Georgia. It may be that changes in the relative abundance of bacterial communities also result in alteration in ARGs, and the community resistance to antibiotics (“resistome”) which in turn increases the potential threat of antibiotic resistance genes. While another part of this study will determine changes in integrons and specific ARGs, this project will focus on changes in bacterial communities and the potential functional changes in the community, which in turn have consequences for ARG levels and its horizontal transfer to various members of the soil community. Addition of waste from livestock is a historical method for increasing nutrients needed in the soil for the cultivation of crops, and in turn causes pronounced shifts in soil microbial communities due to the addition of large amounts of carbon, nutrients, foreign microbes, and other material. This study is unique because it utilizes a novel and relatively large landscape-scale to determine if there are discernable and repeatable patterns of bacterial community structure change in response to amendment regardless of exact soil type or source of chicken litter amendment. In the future, these data can also provide insight into the changes in the relative abundance antibiotic related genes associated with community change.M.S.
Soil is complicated, both in terms of its physical makeup and the organisms that live inside of it. Predicting changes in soil based on the addition of foreign material such as chemicals or biological waste is not an easy process, and whether or not it is even possible to reliably predict those changes is a matter of some dispute. This study is designed to illustrate that such changes can in fact be reliably and consistently predicted even with regard to the addition of complicated materials to the soil. In this study, specifically, the material in question is chicken litter. A mix of the bedding and waste produced by chickens, litter is commonly handled by composting and is added to soil in farms as a fertilizer rich in organic matter. It is possible to point at specific elements of the soil such as the chemistry and bacteria and see how it is changed with the addition of chicken litter, which allows us to determine the nature and extent of the change that chicken litter has on soil. This study is conducted on a larger scale than similar experiments conducted in the past, making it apparent that these relationships exist on a repeated basis. It is the object of this study to pave the way and make it easier for scientists in the future to determine these relationships in other unique contexts.
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Anota, Amelie. "Analyse longitudinale de la qualité de vie relative à la santé en cancérologie." Thesis, Besançon, 2014. http://www.theses.fr/2014BESA3010/document.
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La qualité de vie relative à la santé (QdV) est désormais un des objectifs majeurs des essais cliniques en cancérologie pour pouvoir s’assurer du bénéfice clinique de nouvelles stratégies thérapeutiques pour le patient. Cependant, les résultats des données de QdV restent encore peu pris en compte en pratique clinique en raison de la nature subjective et dynamique de la QdV. De plus, les méthodes statistiques pour son analyse longitudinale doivent être capables de tenir compte de l’occurrence des données manquantes et d’un potentiel effet Response Shift reflétant l’adaptation du patient vis-à-vis de la maladie et de la toxicité du traitement. Ces méthodes doivent enfin proposer des résultats facilement compréhensibles par les cliniciens.Dans cette optique, les objectifs de ce travail ont été de faire le point sur ces facteurs limitants et de proposer des méthodes adéquates pour une interprétation robuste des données de QdV longitudinales. Ces travaux sont centrés sur la méthode du temps jusqu’à détérioration d’un score de QdV (TJD), en tant que modalité d’analyse longitudinale, ainsi que sur la caractérisation de l’occurrence de l’effet Response Shift.Les travaux menés ont donné lieu à la création d’un package R pour l’analyse longitudinale de la QdV selon la méthode du TJD avec une interface facile d’utilisation. Certaines recommandations ont été proposées sur les définitions de TJD à appliquer selon les situations thérapeutiques et l’occurrence ou non d’un effet Response Shift. Cette méthode attractive pour les cliniciens a été appliquée dans le cadre de deux essais de phase précoces I et IL La méthode de pondération par probabilité inversée du score de propension a été investiguée conjointement avec la méthode du TJD afin de tenir compte de l’occurrence de données manquantes dépendant des caractéristiques des patients. Une comparaison de trois approches statistiques pour l’analyse longitudinale a montré la performance du modèle linéaire mixte et permet de donner quelques recommandations pour l’analyse longitudinale selon le design de l’étude. Cette étude a également montré l’impact de l’occurrence de données manquantes informatives sur les méthodes d’analyse longitudinale. Des analyses factorielles et modèles issus de la théorie de réponse à l’item ont montré leur capacité à caractériser la Response Shift conjointement avec la méthode Then-test. Enfin, bien que les modèles à équation structurelles soient régulièrement appliqués pour caractériser cet effet sur le questionnaire de QdV générique SF-36, ils semblent peu adaptés à la structure des questionnaires spécifiques du cancer du groupe « European Organization of Research and Treatment of Cancer » (EORTCHealth-related quality of life (HRQoL) has become one of the major objectives of oncology clinical trials to ensure the clinical benefit of new treatment strategies for the patient. However, the results of HRQoL data remain poorly used in clinical practice due to the subjective and dynamic nature of HRQoL. Moreover, statistical methods for its longitudinal analysis hâve to take into account the occurrence of missing data and the potential Response Shift effect reflecting patient’s adaptation of the disease and treatment toxicities. Finally, these methods should also propose some results easy understandable for clinicians.In this context, this work aimed to review these limiting factors and to propose some suitable methods for a robust interprétation of longitudinal HRQoL data. This work is focused on both the Time to HRQoL score détérioration (TTD) as a modality of longitudinal analysis and the characterization of the occurrence of the Response Shift effect.This work has resulted in the création of an R package for the longitudinal HRQoL analysis according to the TTD with an easy to use interface. Some recommendations were proposed on the définitions of the TTD to apply according to the therapeutic settings and the potential occurrence of the Response Shift effect. This attractive method was applied in two early stage I and II trials. The inverse probability weighting method of the propensity score was investigated in conjunction with the TTD method to take into account the occurrence of missing data depending on patients’ characteristics. A comparison between three statistical approaches for the longitudinal analysis showed the performance of the linear mixed model and allows to give some recommendations for the longitudinal analysis according to the study design. This study also highlighted the impact of the occurrence of informative missing data on the longitudinal statistical methods. Factor analyses and Item Response Theory models showed their ability to characterize the occurrence of the Response Shift in conjunction with the Then- test method. Finally, although the structural équations modeling are often used to characterize this effect on the SF-36 generic questionnaire, they seem not appropriated to the particular structure of the HRQoL cancer spécifie questionnaires of the European Organization of Research and Treatment of Cancer (EORTC) HRQoL group
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Cardozo, Daniela Schiavo 1980. "Efeito do trabalho noturno no controle hormonal da fome e saciedade = Effect of night work on the hormonal control of hunger and satiety." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/308480.
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Orientador: Bruno Geloneze NetoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-24T12:17:34Z (GMT). No. of bitstreams: 1 Cardozo_DanielaSchiavo_D.pdf: 1355414 bytes, checksum: 3c91c18e1699608cf367e306cda835af (MD5) Previous issue date: 2012
Resumo: Devido ao aumento considerável de trabalhadores noturnos é importante o estudo dos efeitos deste tipo de trabalho na saúde do trabalhador. Estudos atuais demonstram que trabalhos em turno e noturno favorecem transtornos digestivos relacionados a diferenças no hábito alimentar, tanto no valor calórico total, como no horário e número de refeições. Além disso, há aumento dos fatores de risco cardiovasculares, tais como: altos níveis de triglicérides e colesterol séricos, obesidade abdominal, resistência à insulina e outros marcadores da síndrome metabólica. Estes fenômenos estão relacionados a um ganho e redistribuição do peso corporal, em parte atribuível a diferenças no padrão de fome e saciedade. Trabalhadores do turno noturno podem apresentar perturbação no ritmo biológico endógeno em função do conflito temporal entre o relógio biológico endógeno e a estrutura de funcionamento das atividades sociais. Esta dessincronização pode produzir transtornos intensos e persistentes na fisiologia do sono. Foram selecionados 12 trabalhadoras de turno noturno e 12 do diurno do HC-UNICAMP, com IMC entre 25 e 29.9 (sobrepeso). O objetivo deste trabalho foi comparar uma população trabalhadora de turno noturno com uma população trabalhadora diurna, em relação a componentes bioquímicos e antropométricos da síndrome metabólica. Além disso, a caracterização das respostas de hormônios reguladores da fome e saciedade foi acessada a partir de um teste de refeição padrão, com dosagens de grelina, (hormônio orexigênico), oxintomodulina, xenina, glucagon-like peptide 1 (GLP-1) e PYY3-36 (hormônios anorexigênicos). A resistência à insulina foi avaliada por índices que relacionam a produção de insulina com a curva glicêmica durante o teste de refeição (Metabolic Clearance Rate, ou índice de Stumvoll). Estes mesmos voluntários foram avaliados quanto à qualidade de sono, ao cronótipo e ao estado inflamatório sub-clínico (avaliado pelos níveis circulantes de interleucina 6, TNF-?, adiponectina e proteína C-reativa). Na avaliação quanto ao cronótipo, a maior proporção de indivíduos indiferentes foram encontrados no grupo do turno noturno. A qualidade de sono avaliada pelo score de Pittsburgh não demonstrou diferença significante entre os grupos estudados. Os trabalhadores de turno noturno demonstraram valores maiores para disfunção diurna, demonstrando sonolência excessiva diurna. O principal achado foi a caracterização de uma resposta de produção do hormônio orexigênico - grelina - aumentada no período pós-prandial das voluntárias de trabalho noturno e uma resposta reduzida de xenina (um hormônio anorexígeno e de fonte estomacal). Assim este fato pode ser responsável pela mudança do comportamento alimentar e consequente ganho de peso destas trabalhadoras de turno noturno.
Abstract: Due to the considerable increase of night shift workers it is important the study of its effects on worker health. Recent studies reveal that work in shifts and night shift work propitiate digestive disorders related to differences in dietary habits, in the total caloric content, as well as in the timing and number of meals. Moreover, it is noticed an increase in cardiovascular risk factors such as high levels of triglycerides and cholesterol, and abdominal obesity, insulin resistance and markers of metabolic syndrome. These phenomena are related to gain and redistribution of body weight, in part attributable to changes in the pattern of hunger and satiety. Night shift workers may have endogenous biological rhythm disturbance as a result of the temporal conflict between the endogenous biological clock and the functioning structure of social activities. This asynchronization may produce intense and persistent disorders in sleep physiology. We selected 12 night shift workers and 12 day workers of the HC-UNICAMP, with BMI between 25 and 29.9 (overweight). The objective of this study was to compare a population of night shift workers with a daytime working population in relation to anthropometric and biochemical components of the metabolic syndrome. Besides that, the characterization of the responses of hormones regulating hunger and satiety was accessed by means of a standard meal test , with dosages of ghrelin, oxyntomodulin, xenin, glucagon-like peptide 1 (GLP-1) and PYY3-36. Insulin resistance was evaluated by indexes relating the production of insulin during the glycemic test meal (Stumvol index). These same volunteers were evaluated for the quality of sleep, the chronotype and sub-clinical inflammatory state (assessed by circulating levels of interleukin-6, TNF-?, adiponectin and protein C-reactive). In the assessment for the chronotype, the highest proportion of indifferent individuals were found in the group of night shift. The quality of sleep assessed by pittsburgh score showed no significant difference between groups. The night shift workers showed higher values for daytime dysfunction, demonstrating excessive daytime sleepiness. The main finding was the characterization of a increased response in production of hormone - ghrelin - in the postprandial period of night shift workers and reduced response of xenina (an anorectic hormone source and stomach). As a conclusion, this fact may be responsible for the weight gain observed for those night shift workers.
Doutorado
Clinica Medica
Doutora em Clínica Médica
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Nimon, Kim F. "Comparing outcome measures derived from four research designs incorporating the retrospective pretest." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3931/.
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Over the last 5 decades, the retrospective pretest has been used in behavioral science research to battle key threats to the internal validity of posttest-only control-group and pretest-posttest only designs. The purpose of this study was to compare outcome measures resulting from four research design implementations incorporating the retrospective pretest: (a) pre-post-then, (b) pre-post/then, (c) post-then, and (d) post/then. The study analyzed the interaction effect of pretest sensitization and post-intervention survey order on two subjective measures: (a) a control measure not related to the intervention and (b) an experimental measure consistent with the intervention. Validity of subjective measurement outcomes were assessed by correlating resulting to objective performance measurement outcomes. A Situational Leadership® II (SLII) training workshop served as the intervention. The Work Involvement Scale of the self version of the Survey of Management Practices Survey served as the subjective control measure. The Clarification of Goals and Objectives Scale of the self version of the Survey of Management Practices Survey served as the subjective experimental measure. The Effectiveness Scale of the self version of the Leader Behavior Analysis II® served as the objective performance measure. This study detected differences in measurement outcomes from SLII participant responses to an experimental and a control measure. In the case of the experimental measure, differences were found in the magnitude and direction of the validity coefficients. In the case of the control measure, differences were found in the magnitude of the treatment effect between groups. These differences indicate that, for this study, the pre-post-then design produced the most valid results for the experimental measure. For the control measure in this study, the pre-post/then design produced the most valid results. Across both measures, the post/then design produced the least valid results.
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Wendelberger, Kristie Susan. "Evaluating plant community response to sea level rise and anthropogenic drying: Can life stage and competitive ability be used as indicators in guiding conservation actions?" FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2558.
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Increasing sea levels and anthropogenic disturbances have caused the world’s coastal vegetation to decline 25-50% in the past 50 years. Future sea level rise (SLR) rates are expected to increase, further threatening coastal habitats. In combination with SLR, the Everglades ecosystem has undergone large-scale drainage and restoration changing Florida’s coastal vegetation. Everglades National Park (ENP) has 21 coastal plant species threatened by SLR. My dissertation focuses on three aspects of coastal plant community change related to SLR and dehydration. 1) I assessed the extent and direction coastal communities—three harboring rare plant species—shifted from 1978 to 2011. I created a classified vegetation map and compared it to a 1978 map. I hypothesized coastal communities transitioned from less salt- and inundation-tolerant to more salt- and inundation-tolerant communities. I found communities shifted as hypothesized, suggesting the site became saltier and wetter. Additionally, all three communities harboring rare plants shrunk in size. 2) I evaluated invading halophyte (salt-tolerant) plant influence on soil salinity via a replacement series greenhouse experiment. I used two halophytes and two glycophytes (non-salt-tolerant) to look at soil salinity over time under 26 and 38‰ groundwater. I hypothesized that halophytes increase soil salinity as compared to glycophytes through continued transpiration during dry, highly saline periods. My results supported halophytic influence on soil salinity; however, not from higher transpiration rates. Osmotic or ionic stress likely decreased glycophytic biomass resulting in less overall plant transpiration. 3) I assessed the best plant life-stage to use for on-the-ground plot-based community change monitoring. I tested the effects of increasing salinity (0, 5, 15, 30, and 45‰) on seed germination and seedling establishment of five coastal species, and compared my results to salinity effects on one-year olds and adults of the same species. I hypothesized that seedling establishment was the most vulnerable life-stage to salt stress. The results supported my hypothesis; seedling establishment is the life-stage best monitored for community change. Additionally, I determined the federally endangered plant Chromolaena frustrata’s salinity tolerance. The species was sensitive to salinity >5‰ at all developmental stages suggesting C. frustrata is highly threatened by SLR.
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Harnden, Alice Claire. "Responsive shift probes for magnetic resonance." Thesis, Durham University, 2019. http://etheses.dur.ac.uk/12951/.
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Magnetic resonance chemical shift imaging can provide chemical information about biological tissue. However, 1H MR shift imaging in vivo is a much less exploited technique than standard MRI, due to the presence of strong NMR signals from water and fat. Paramagnetic lanthanide(III) complexes, in which a tert-butyl reporter group is incorporated, can be used to shift a proton resonance ±80 ppm from the water signal allowing selective observation. The proximity of the paramagnetic lanthanide(III) ion enhances the longitudinal relaxation rates of the surrounding nuclei, permitting faster data acquisition per unit time. The chemical shifts of paramagnetically shifted proton resonances, within kinetically stable macrocyclic lanthanide(III) complexes, inherently encode temperature information. The introduction of a phosphonate group adjacent to the tert-butyl reporter group introduces pH responsive behaviour. The dual sensitivity of such probes has allowed the simultaneous triple imaging of the water signal and the shifted tert butyl signals of thulium(III) and dysprosium(III) complexes of a common ligand, separated by over 160 ppm. Spectral imaging experiments in vivo allow the pH and temperature of the liver, kidney and bladder to be measured within a mouse model. Further modification of the ligand structure changes the biodistribution profile of the complex whilst maintaining and even improving the chemical shift and relaxation rates of the probe. In-depth structural and NMR analysis of a series of lanthanide complexes based on different ligand motifs has demonstrated that the MR properties of a paramagnetic complex cannot be readily predicted using the longstanding theories of shift and relaxation. Seemingly small modifications to ligand structure can significantly alter the size, magnitude, sign and orientation of the magnetic susceptibility tensor. Finally, introduction of a specific zinc(II) ion chelating agent adjacent to the tert-butyl reporter group has created the first zinc(II) responsive paramagnetic probe for proton magnetic resonance spectroscopy. The strong and selective binding of zinc(II) was shown to be reversible.
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Ousmen, Ahmad. "Détermination du sens clinique d'un changement pour les questionnaires de qualité de vie relative à la santé en cancérologie." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCE001/document.
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En cancérologie, la qualité de vie relative à la santé (QdV) est considérée comme second critère de jugement principal dans les essais cliniques en l’absence d’effet sur la survie globale. L’interprétation des scores de QdV et d’une différence de scores cliniquement pertinente entre deux temps de mesure est un problème majeur en QdV. Cette différence peut être significative d’un point de vue statistique sans être cliniquement significative du point de vue du patient. La différence minimale cliniquement importante (DMCI) a ainsi été définie comme la plus petite différence de score de QdV qui serait considérée comme ayant un sens clinique pour le patient. L’analyse longitudinale de la QdV est complexe, en particulier en raison de l’occurrence de l’effet « Response Shift » qui est susceptible de biaiser les résultats d’analyse longitudinal et en particulier les résultats de la DMCI. Dans ce contexte, le premier objectif de ce travail de thèse est une revue de la littérature concernant la détermination de la DMCI selon les méthodes les plus couramment utilisées : les méthodes basées sur l’ancre et les méthodes basées sur la distribution. Deuxièmement, calculer la DMCI par les méthodes basées sur l’ancre et la distribution en appliquant différents critères de distribution et plusieurs ancres différentes. L’objectif est de comparer les résultats obtenus par les différentes méthodes et de les comparer également avec les résultats obtenus par les études antérieures. Enfin, étudier l’impact de l’occurrence de l’effet Response Shift sur la détermination de la DMCI pour les questionnaires de QdV en cancérologieIn oncology, the health-related quality of life (HRQOL) is generally considered as a second endpoint in the clinical trials. The interpretation of the results of the longitudinal analysis of such data must be made in both statistical and clinical point of view in order to produce meaningful results for both patients and clinicians. The main objective is to assess the impact of the treatment on patient’s HRQOL level over time. The minimal clinically important difference (MCID) was defined as the smallest change between two scores in a treatment outcome that a patient would identify as important. Indeed, the longitudinal analysis of HRQOL remains complex, particularly due to the potential occurrence of a Response Shift effect characterizing the process of adaptation of the patient in relation to the illness and its treatment. Hence, the first objective of this work is a literature review concerning the determination of the MCID by the most commonly used methods: anchor-based and distribution-based methods. Secondly, calculating the MCID using anchor-based and distribution-based methods by applying different distribution criteria and several different anchors. The objective is to compare the results obtained by the different methods and to compare them to others obtained by previous studies. Finally, studying the impact of the Response Shift effect on the determination of MCID for the HRQOL questionnaires in cancer research using several data corresponding to different therapeutic situations and cancer locations
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Davy, Jonathan Patrick. "The effects of a gradual shift rotation and a split shift nap intervention on cognitive, physiological and subjective responses under simulated night shift settings." Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/517.
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Introduction: Shift work, particularly work that occurs at night has been associated with numerous challenges to occupational safety and productivity. This stems from the associated extended wakefulness, circadian disruptions and sleep loss from the inversion of the sleep wake cycle, which predisposes shift workers to reduced alertness, increased fatigue and decrements in performance capacity. These effects may be exacerbated over consecutive night shifts as a result of reductions in sleep length associated with attempting to sleep against the alerting signals of the circadian rhythm during the day. Although a variety of shift work countermeasures exist, new and innovative fatigue management strategies are needed to mitigate the effects of night work. This study proposed two night shift interventions; the Rolling rotation and a split shift nap combination. Aims: The aim of this study was to explore the effects of these interventions to a conventional Fixed night shift arrangement. Selected performance, physiological and subjective measures were applied to track any effects during a five-day shift work study. Methods: The study was laboratory-based and performance was quantified through the application of computer-based perceptual, cognitive and motor tests. Student participants (24 females and 21 males) partook in the study, which adopted a nonrepeated measures design and spanned five consecutive days. During this time, participants were required to perform a simple beading task over five 8-hour shifts. Participants were split according to sex and chronotype between four independent conditions; 1. Fixed night condition required participants to complete one afternoon shift (14h00 – 22h00) and four consecutive night shifts (22h00 - 06h00) 2. Rolling rotation condition gradually “rolled” participants into the night shift by delaying the start and end of an afternoon shift by two hours each day (16h00 – 00h00, 18h00 – 02h00, 20h00 – 04h00, 22h00 – 06h00) until the times matched that of the Fixed night condition. 3. The split shift nap system was made up of two independent groups, both of which completed one afternoon (14h00 to 22h00) and four night shifts. The Nap early condition worked from 20h00 to 08h00, napping between 00h00 and 04h00, while the Nap late condition worked from 00h00 to 12h00 and napped between 04h00 and 08h00 during the night shifts. Napping, the opportunity for which was 200 minutes occurred in the laboratory, but post shift recovery sleep, for all conditions, happened outside the laboratory. During each shift, six test batteries were completed, in which the following measures were taken: 1. Performance: beading output, eye accommodation time, choice reaction time, visual vigilance, simple reaction time, processing speed and object recognition, working memory, motor response time and tracking performance. 2. Physiological: heart rate, heart rate variability (r-MSSD, normalised Low frequency power: LFnu). 3. Self-reported measures: subjective sleepiness and reported sleep length and quality while outside the laboratory. Results: Analyses revealed that: 1. Measures of beading performance, simple reaction time, vigilance and object recognition, working memory, motor response time and control, all physiological measures, except LFnu and subjective sleepiness demonstrated the effects of time of day / fatigue, irrespective of condition. 2. There was no evidence of cumulative fatigue over the four night shifts in the performance and subjective measures and most of the physiological indicators. Beading output decreased significantly over the course of the night shifts, while reported post shift sleep length was significantly reduced with the start of the night shifts, irrespective of condition. 3. The majority of the physiological and performance measures did not differ significantly between conditions. However, there were some effects: the Rolling rotation condition produced the highest beading output compared to the Nap late condition; working memory was significantly lower in the Nap late condition compared to the other conditions. Furthermore, the nap opportunity in both the Nap early and Nap late conditions reduced subjective sleepiness, while napping during the night shift reduced post shift sleep length compared to the Rolling rotation and Fixed night conditions. There was also evidence of sleep inertia following pre-post nap test comparisons, which mainly affected visual perception tasks in both nap conditions. Sleep inertia possibly also accounted for an apparent dissociation between subjective and performance measures. Conclusions: Quantifying and interpreting the effects of night shift work in a laboratory setting has limitations. These stem mainly from the limited ecological validity of the performance outcome measures adopted and the characteristics of the sample that is tested. However, in order to fully understand the efficacy of any shift work countermeasure, the laboratory setting offers a safe, controlled environment in which to do so. The conclusions should thus be considered in light of these limitations. Night shift work negatively affected all elements of human information processing. The combination of reduced physiological arousal, extended wakefulness, increased perceptions of sleepiness and reduced total sleep obtained explained these decrements in performance. While cumulative fatigue has been reported as a challenge associated with night shift work, there was no conclusive evidence of this in the current study. In the case of the Rolling rotation, the gradual introduction to the night shift delayed the inevitable reduction in alertness and performance, which limits the viability of this intervention. The inclusion of the nap interventions was associated with reduced perceptions of sleepiness, which did not translate into improved performance, relative to the Rolling rotation and Fixed night conditions. Apart from considerations of how to manage sleep inertia post nap, the split shift nap intervention can provide an alternative to conventional night shift work arrangements.
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Ribeiro, David. "Hormonal and metabolic responses in simulated and real shift work." Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/843353/.
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Coronary Heart Disease (CETO) is one of the most common causes of mortality in industrialised societies, and it has been demonstrated elsewhere that shift workers have an increased risk of developing CHD compared to day-workers. One possible explanation for this increased risk is that a shift worker may show inappropriate postprandial responses to a night-time meal, when their biological clock is not adapted to the night shift. This could lead to an elevation in the circulating levels of certain hormones and metabolites, such as triacylglycerol (TAG) and insulin, which are known to be risk factors for CHD. This thesis investigated the relationships between meal times and postprandial hormone and metabolic responses in simulated and real-life shift-workers. The work is presented as three major clinical trials. In the first of these, a combination of timed bright light and darkness/sleep was used to induce a gradual 9-hour phase advance in 12 healthy subjects, who then underwent a rapid 9-hour phase delay. Three meal study days were arranged, to occur during the baseline condition, immediately after the rapid phase delay, so that the subjects effectively had "simulated jet lag", and two days later. Blood parameters measured included plasma glucose, insulin, proinsulin, C-peptide, non-esterified fatty acids (NEFA), TAG and glucose- dependent insulinotropic polypeptide (GIP). Substantial differences in plasma TAG and NEFA were observed in the postprandial responses when the subjects consumed an identical meal immediately after the rapid phase delay, compared with during the baseline conditions. Two days after the rapid phase delay, subjects showed inteimediate hormone and metabolite levels, suggesting that the biological clock had a major effect on these postprandial responses. In the second study, day and night-time postprandial responses were compared in a simulated shift work environment, and the effectiveness of a number of potentially beneficial procedures was investigated. These included alterations to the content of the meal consiraied prior to the night shift, bright light exposure during the night shift, and a daytime rest period prior to the night shift. As in the first study, significant differences were seen in a number of hormones and metabolites on the night shift. compared with during the day. The content of the previous meal, bright light exposure and a daytime rest period prior to the night shift all had significant effects on the night-time postprandial responses. The most exciting discovery made was that a single 8-hour night-time bright light exposure significantly lowered the TAG postprandial responses on the simulated night shift. As all the work conducted up until this point had utilised simulated conditions, it was important to illustrate that similar differences in postprandial responses at night-time could be demonstrated in "real-life shift workers". Thus, nine midwives were recruited from the Royal Surrey County Hospital, and studied on four occasions. This allowed comparison of postprandial responses on both day and night shifts, and also allowed further investigation of the effect of altering the content of the previous meal. Significant differences were again found in a number of blood parameters when the night-time and day-time responses to the test meal were compared, with the most striking being a delayed NEFA rise on the night shift, compared with during the day. In conclusion, this series of studies have illustrated that the human body responds differently to a meal consumed at night-time, compared with during the day, both in a simulated and a real-life environment. This results in variations in the levels of a number of known CHD risk factors, and may be linked with the elevated CHD risk reported in shift workers. Alteration to the meal prior to the night shift, exposure to bright light during the night shift, and instituting a rest period prior to the night shift, were all shown to be potentially beneficial in reducing the variation between day and night-time responses.
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Ran, Hongjun. "A Framework for the Determination of Weak Pareto Frontier Solutions under Probabilistic Constraints." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14511.
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A framework is proposed that combines separately developed multidisciplinary optimization, multi-objective optimization, and joint probability assessment methods together but in a decoupled way, to solve joint probabilistic constraint, multi-objective, multidisciplinary optimization problems that are representative of realistic conceptual design problems of design alternative generation and selection. The intent here is to find the Weak Pareto Frontier (WPF) solutions that include additional compromised solutions besides the ones identified by a conventional Pareto frontier. This framework starts with constructing fast and accurate surrogate models of different disciplinary analyses. A new hybrid method is formed that consists of the second order Response Surface Methodology (RSM) and the Support Vector Regression (SVR) method. The three parameters needed by SVR to be pre-specified are automatically selected using a modified information criterion based on model fitting error, predicting error, and model complexity information. The model predicting error is estimated inexpensively with a new method called Random Cross Validation. This modified information criterion is also used to select the best surrogate model for a given problem out of the RSM, SVR, and the hybrid methods. A new neighborhood search method based on Monte Carlo simulation is proposed to find valid designs that satisfy the deterministic constraints and are consistent for the coupling variables featured in a multidisciplinary design problem, and at the same time decouple the three loops required by the multidisciplinary, multi-objective, and probabilistic features. Two schemes have been developed. One scheme finds the WPF by finding a large enough number of valid design solutions such that some WPF solutions are included in those valid solutions. Another scheme finds the WPF by directly finding the WPF of each consistent design zone. Then the probabilities of the PCs are estimated, and the WPF and corresponding design solutions are found. Various examples demonstrate the feasibility of this framework.
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Ramos, Diana Catalina Serrano. "Manutenção de respostas de observação por classes de estímulos formadas por reversões repetidas de discriminações simples simultâneas." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-22112013-123707/.
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Estudos demonstram que estímulos discriminativos de maiores probabilidades de reforço mantêm respostas de observação. Por sua vez, estímulos que compartilham funções discriminativas podem compor uma classe funcional de estímulos. Em vista disso, esta pesquisa investigou se estímulos que compartilhavam funções discriminativas, ao formar classes funcionais, passariam a reforçar respostas de observação. Dez adultos foram expostos a um treino discriminativo simples simultâneo com dois conjuntos de quatro estímulos cada. Na sequência, de modo a estabelecer classes funcionais, foram realizadas quatro reversões de contingências com tentativas de teste (sonda). Durante todo o procedimento, os participantes usaram um equipamento de rastreamento ocular para mensurar suas respostas de observação. Os resultados mostraram que oito participantes aprenderam as discriminações; sete participantes mostraram formação de classes funcionais com pelo menos um dos conjuntos usados; e, para um participante, não houve formação de classes. A avaliação das respostas de observação mostrou que, para quatro participantes, estímulos que compuseram em classes funcionais passaram a manter correspondentemente respostas de observação, sugerindo que, ao se estabelecerem como classes de estímulos discriminativos, os estímulos passaram a exercer funções reforçadoras condicionadas para respostas de observação. Dessa forma, classes de estímulos discriminativos constituem-se, também, como classes de reforçadores condicionadosStudies have demonstrated that discriminative stimuli paired with high probabilities of reinforcement maintain observing responses in a higher rate than those stimuli paired with low probabilities of reinforcement or extinction. On the other hand, stimuli that share discriminative functions may become a functional stimulus-class. Considering this, the present research evaluated whether stimuli that share discriminative functions by becoming a functional class would also acquire a reinforcing function for observing responses. Ten adults were submitted to a simple simultaneous discriminative training with two sets of four stimuli each. Then, to establish functional classes, four contingency reversals with test trials were conducted. Throughout the procedure, participants observing responses were measured with an eye-tracker device. Eight participants learned the discriminations. Seven participants showed evidence of functional class formation for at least one of the sets used, and one participant showed no evidence of functional class formation. Observing measures showed that the stimulus-set that became functional classes for four participants also maintained their observing responses. These data suggest that, when a set of stimuli becomes a discriminative stimulus-class, the stimuli in the set acquire conditioned reinforcement functions for observing responses. This evidence suggests that discriminative stimulus-classes are classes of conditioned reinforcers
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Nolte, Sandra, and sandra nolte@mh org au. "Approaches to the measurement of outcomes of chronic disease self-management interventions using a self-report inventory." RMIT University. Global Studies, Social Science & Planning, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080822.151606.
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Background Health education programs that are aimed at improving individuals' skills to self-manage are increasingly recognised as a critical component of chronic disease management. Despite the apparent need for such interventions, current studies show inconsistent results regarding program effectiveness, with meta-analyses indicating only marginal effects for some disease groups. A closer examination of these studies however suggests that the magnitude and inconsistency of the findings may be related to the types of outcomes that were assessed rather than specific disease groups. Where self-report measures were used, results tended to be smaller and inconsistent. It is therefore possible that current studies do not adequately reflect program effects because self-report outcomes have a high risk to be confounded by a range of potential biases. Objective The aim of this thesis was to identify and quantify the potential influence of biases in the measurement of change in chronic disease self-management interventions using self-report. Methods The research design targeted the processes that individuals undergo when filling out questionnaires and whether this has an influence on their self-report outcomes. This was achieved by developing a three-group research design. The Health Education Impact Questionnaire (heiQ) was used to collect outcomes data. While pretest questionnaires were identical across groups, three questionnaire versions were randomly distributed at posttest. One of the groups filled out traditional posttest questions (n=331), whereas the other two groups were asked to provide data in addition to posttest questions, with one group providing transition questions (n=304) and one providing retrospective pretest data (n=314). Resulting datasets were further examined for possible confounding effects through response shift and social desirability bias. Through the random allocation of the heiQs it was ensured that data were not influenced by potential intra-group effects. Results The thesis revealed that the design of the posttest questionnaire significantly influenced people's ratings of their posttest levels. In particular, when participants were asked to provide ratings of their retrospective pretest levels in addition to their posttest levels, the latter scores were significantly higher than those of participants who did not perform this additional task. Subsequent analyses however suggested that these differences could neither be explained by response shift nor by social desirability bias. Conclusions This research has provided important insight into the measurement of outcomes of chronic disease self-management interventions. While the threat to the validity of traditional pretest-posttest data due to confounding effects through response shift and social desirability biases could not be supported, the thesis has highlighted that the cognitive task that subjects are asked to perform when providing data at posttest significantly influenced their self-reported outcomes. Given that previous research has predominantly focused on other aspects of validity - such as applying control group designs to circumvent common threats to internal and external validity - this study suggests that more attention must be paid to the design of questionnaires. The thesis concludes that further research, in particular into the influence of cognitive tasks on obtained scores, is important to improve the interpretation of self-report outcomes data derived from participants of self-management interventions.
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Myers, Stephen Anthony. "Kallikrein Gene Regulation in Hormone-Dependent Cancer Cell Lines." Queensland University of Technology, 2003. http://eprints.qut.edu.au/15842/.
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Hormone-dependent cancers (HDCs), such as those of the prostate, ovary, breast and endometrium, share characteristics that indicate similar underlying mechanisms of carcinogenesis. Through steroid hormone signalling on "down-stream" target genes, the growth, development and progression of HDCs are regulated. One such family of target genes, highly expressed in HDCs and regulated by steroid hormones, are the tissue kallikreins (KLKs). The KLKs are a multigene family of serine proteases involved in physiological processes such as blood pressure regulation, inflammation, and tumour development and progression via the hydrolysis of specific substrates. Although the KLK gene family is clearly implicated in tumourigenesis, the precise roles played by these genes are largely unknown. Additionally, except for the androgen-responsive genes, KLK2 and KLK3, the mechanisms underlying their hormonal regulation in HDCs are yet to be identified. The initial focus of this thesis was to examine the regulation of the kallikreins, KLK1 and KLK4, by estradiol and progesterone in endometrial and breast cancer cell lines. From these studies, progesterone clearly regulated KLK4 expression in T47D cells and therefore, the focus of the remaining studies was to further examine this regulation at the transcriptional level. An overview of the results obtained is detailed below. Human K1 and hK4 protein levels were increased by 10 nmol/L estradiol benzoate, progesterone, or a combination of the two, over 48 hours in the endometrial cancer cell line, KLE. However, these same treatments resulted in no change in KLK1 gene or hK1 protein levels in the endometrial cancer cell lines, HEC1A or HEC1B (only hK1 analysed). Progesterone treatment (0-100 nmol/L) over 24 hours resulted in a clear increase in KLK4 mRNA at the 10 nmol/L dose in the breast cancer cell line, T47D. Additionally, treatment of T47D cells with 10 nmol/L progesterone over 0-48 hr, resulted in the rapid expression of the hK4 protein at 2 hr which was sustained for 24 hr. Further analysis of this latter progesterone regulation with the antiprogesterone, RU486, over 24 hours, resulted in an observable decrease in hK4 levels at 1 µmol/L RU486. Although the estrogen and progesterone regulation of the hK1 protein was not further analysed, the data obtained for hK4 regulation in T47D cell lines, supported the premise that this gene was progesterone-responsive. The rapid expression of hK4 protein by progesterone at two hours suggests that KLK4 transcription is directly coupled to progesterone regulation, perhaps through progesterone receptor (PR) binding to progesterone-responsive regions within the KLK4 promoter or far "up-stream" regions. Thus, the following further studies were performed. To test this hypothesis, the transcription initiation site (TIS) and 5' flanking regions of the KLK4 gene in T47D cells were interrogated. Primer extension and 5' RACE identified the TIS 78 bp 5' of the putative ATG site for translation as identified by Korkmaz et al. (2001). This KLK4 gene transcript consists of only four exons, and thus excludes the pre/pro signal peptide. Although a TATA-box is not present within -25 to -30 bp 5' of the identified TIS, a number of consensus binding motifs for Sp1 and estrogen receptor half-sites were identified. It is possible that the Sp1 sites are involved in the basal levels of transcription for this gene. Additionally, a putative progesterone response element (PRE) was identified in the far "up-stream" regions of the KLK4 gene. Basal levels of transcription were observed within the KLK4 proximal promoter region when coupled to a luciferase reporter gene and transfected into T47D cell lines. Additionally, the KLK4 proximal promoter region did not induce the luciferase reporter gene expression when progesterone was added to the system, however, estradiol was inhibitory for luciferase gene expression. This suggests that the proximal promoter region of the KLK4 gene could contain functional EREs but not PREs. In keeping with this hypothesis, some ER half-sites were identified, but PR sites were not obvious within this region. The identified PRE in the far "up-stream" region of the KLK4 gene assembled the progesterone receptor in vitro, and in vivo, as assessed by electromobility shift assays and chromatin immunoprecipitation assays (EMSAs and ChIPs), respectively. The binding of the PR to the KLK4 PRE was successfully competed out by a PR antibody and not by an androgen receptor antibody, and thus confirms the specificity of the KLK4 PRE-PR complex. Additionally, the PR was recruited and assembled onto and off the progesterone-responsive KLK4 region in a cyclic fashion. Thus, these data strongly suggest that the PR represents one of the core components of a transcription complex for the KLK4 gene, and presumably also contributes to the expression of this gene. Moreover, these data suggest a functional coordination between the PR and the KLK4 progesterone-responsive region in T47D cells, and thus, provide a model system to further study these events in vivo.
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Fitzsimmons, James. "Ecological Responses to Threats in an Evolutionary Context: Bacterial Responses to Antibiotics and Butterfly Species’ Responses to Climate Change." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23807.
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Humans are generally having a strong, widespread, and negative impact on nature. Given the many ways we are impacting nature and the many ways nature is responding, it is useful to study responses in an integrative context. My thesis is focused largely (two out of the three data chapters) on butterfly species’ range shifts consistent with modern climate change in Canada. I employed a macroecological approach to my research, drawing on methods and findings from evolutionary biology, phylogenetics, conservation biology, and natural history. I answered three main research questions. First, is there a trade-off between population growth rate (rmax) and carrying capacity (K) at the mutation scale (Chapter 2)? I found rmax and K to not trade off, but in fact to positively co-vary at the mutation scale. This suggests trade-offs between these traits only emerge after selection removes mutants with low resource acquisition rates (i.e., unhealthy genotypes), revealing trade-offs between remaining genotypes with varied resource allocation strategies. Second, did butterfly species shift their northern range boundaries northward over the 1900s, consistent with climate warming (Chapter 3)? Leading a team of collaborators, we found that most butterfly species’ northern range boundaries did indeed shift northward over the 1900s. But range shift rates were slower than those documented in the literature for more recent time periods, likely reflecting the weaker warming experienced in the time period of my study. Third, were species’ rates of range shift related to their phylogeny (Chapter 3) or traits (Chapter 4)? I found no compelling relationships between rates of range shift and phylogeny or traits. If certain traits make some species more successful at northern boundary range expansion than others, their effect was not strong enough to emerge from the background noise inherent in the broad scale data set I used.
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Lai, John. "Functional analyses of polymorphisms in the promoters of the KLK3 and KLK4 genes in prostate cancer." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16454/.
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This PhD aimed to elucidate the mechanisms by which polymorphisms may alter androgen-induced transactivation of androgen receptor (AR) target genes which may be important in prostate cancer aetiology. The second aspect of this PhD focused on identifying and characterising functional polymorphisms that may have utility as predictive risk indicators for prostate cancer and which may aid in earlier therapeutic intervention and better disease management. Analyses were carried out on the kallikrein-related peptidase 3 (KLK3), also known as the prostate specific antigen (PSA), gene and the kallikrein-related peptidase 4 (KLK4) gene. The PSA and KLK4 genes are part of the serine protease family that have trypsin or chymotrypsin like activity and are thought to play a role in the development of hormone-dependent cancers in tissues such as those in the prostate, breast, endometrium and ovaries. In the prostate, PSA is regulated by androgens and three androgen response elements (AREs) have been described in the promoter and upstream enhancer region. The PSA ARE I harbours a polymorphism at -158 bp from the transcription initiation site (TIS) that results in a G to A transition (G-158A). This PhD investigated the functional significance of the PSA G-158A polymorphism which has been reported to be associated with prostate cancer risk. Electromobility shift assays (EMSAs) investigating the interaction of ARE I variants with the AR DNA binding domain (AR-DBD) demonstrated that the A allele had a two-fold increased binding affinity for the AR-DBD when compared with the G allele. This was confirmed with endogenous AR in limited proteolysis-EMSA experiments. The limited proteolysis-EMSA experiments also demonstrated differential sensitivities of PSA ARE I alleles to trypsin digestion, which suggests that the G-158A polymorphism has an allosteric effect on the AR that alters AR/ARE I complex stability. Furthermore, Chromatin Immunoprecipitation (ChIP) assays suggest that the A allele more readily recruited the AR in vivo when compared with the G allele and is consistent with the in vitro binding data. Luciferase reporter assays carried out in both LNCaP and 22Rv1 prostate cancer cells, and using the natural (dihydrotestosterone; DHT) ligand demonstrated that the A allele was more responsive to androgens in LNCaP cells. Hence, this study has elucidated the potential mechanisms by which the G-158A polymorphism may differentially regulate PSA expression (of which up-regulation of PSA is thought to be important in prostate cancer development and progression). KLK4 has similar tissue-restricted expression as PSA and is up-regulated by steroid hormones in many endocrine cells including those in the prostate. A putative ARE (KLK4-pARE) located at -1,005 to -1019 relative to the more predominantly used transcription initiation site, TIS3, was initially found in supershift assays using AR antibodies to interact with endogenous AR. However, subsequent EMSA analysis using purified AR-DBD suggest that KLK4-pARE may be interacting with the AR indirectly. To investigate this hypothesis, a tandem construct of KLK4-pARE was cloned into the pGL3-Promoter vector for hormone-induced reporter assays. However, reporter assays did not demonstrate any responsiveness of KLK4-pARE to androgens, estradiol or progestins. Consequently, Real-Time PCR was carried out to reassess the hormonal regulation of KLK4 at the mRNA level. Consistent with the literature, data from this study suggests that KLK4 may be up-regulated by androgens, progestins and estradiol in a cyclical manner. Hormone-induced luciferase reporter assays were then carried out on seven promoter constructs that span 2.8 kb of the KLK4 promoter from TIS3. However, none of the seven promoter constructs demonstrated any significant responsiveness to androgens, estradiol or progestins. This study suggests that hormone response elements (HREs) that may drive the hormonal regulation of KLK4 in prostate cancer may be located further upstream from the promoter region investigated in this PhD, or alternatively, may lie 3' of TIS3. The characterisation of KLK4 promoter polymorphisms and their flanking sequences were also carried out in parallel to the functional work with the intent to assess the functional significance of any polymorphisms that may be located within HREs. In total 19 polymorphisms were identified from the public databases and from direct sequencing within 2.8 kb of the KLK4 promoter from TIS3. However, the functional and clinical significance of these 19 polymorphisms were not further pursued given the negative findings from the functional work. The PSA AR enhancer region was also assessed for potential polymorphisms that may be associated with prostate cancer risk. A total of 12 polymorphisms were identified in the PSA enhancer of which two (A-4643G and T-5412C) have been reported to alter functionality of the enhancer region and thus, prioritised for further analysis. Association analysis for prostate cancer risk was then carried out on these PSA enhancer polymorphisms as none of the KLK4 promoter polymorphisms were found in functional HREs. No significant association for either the A-4643G or T-5412C polymorphism with prostate cancer risk was found at the P = 0.05 level. However, under an age-adjusted dominant model a 1.22- (95% CI = 1.16-1.26) and 1.23-fold (95% CI = 1.17-1.29) increased risk for prostate cancer was found for the A-4643G or T-5412C polymorphisms, respectively. Both polymorphisms were also assessed for association with tumour grade and stage and PSA levels. Genotypes were significantly different for the A-4643G and T-5412C polymorphisms with tumour stage and PSA levels, respectively. However, these results are likely to be biased by the case population which consist primarily of men who presented with incidental (pT1) and organ-confined (pT2) tumours. To summarise, the A-4643G and T-5412C polymorphisms are unlikely to be associated with prostate cancer risk, PSA levels or stage/grade of disease. However, further analyses in a larger cohort is warranted given that these polymorphisms alter androgen responsiveness of the PSA enhancer and that elevated PSA levels are indicative of men with prostate cancer. To summarise, this PhD has elucidated the functional significance of the PSA G-158A polymorphism in prostate cancer and which may be important in prostate cancer patho-physiology. This PhD has also furthered the understanding of the hormonal regulation of KLK4 in prostate cancer cells. Finally, this PhD has carried out a pilot study on two functional PSA enhancer polymorphisms (A-4643G and T-5412C) with prostate cancer risk.
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Suherman, Surjani. "Response of a cracked rotating shaft with a disk during passage through a critical speed." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09292009-020146/.
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Soria, Carlos. "Gas turbine shaft over-speed / failure modelling: aero/thermodynamics modelling and overall engine system response." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/12131.
Full textAbstract:
Gas turbine design needs of high-speed turbomachinery whose layout is organised in
compressor-turbine pairs mechanically linked by concentric shafts. The mechanical
failure of a shaft leads to compressor-turbine decoupling provoking the acceleration
of the free-running turbine. In view of such scenario, it is of paramount importance
to guaranty the mechanical integrity of the turbine, in terms of high energy
debris release. Certification authorities require proof that any possible failure will be
contained; admitting the reliable simulation capability of the event as certification
strategy.
The objectives of this research activity have aimed at the development of reliable
simulation tools based on analytical and semi-empirical models. The integration
of all the different models/modules together in an “all-in-one” tool provides the
sponsor company with the capability to simulate and assess various shaft over-speed
scenarios during the early stages of an engine's design and development program.
Shaft failure event cannot be understood unless engine components interaction and
fast transient effects are taken into account in a global manner. The high vibration
level consequence of the breakage, or the thermodynamic mismatch due to the rapid
free-running compressor deceleration, trigger the surge of the compression system
which affects to the performance of every engine component. Fully-transient simulation
capability to model compression system post-stall performance and secondary
air system behaviour has been developed. Component map prediction tools have
been created for compressor reverse flow performance and turbines affected by inlet
distorted flows.
The development of the so-called “all-in-one” simulation tool has been completed and
it has been applied to the modelling of a real case of shaft failure. Reliable prediction
of thermodynamic properties evolution and over-speeding turbine terminal speed
have been shown. The robustness and flexibility of the simulation tool have been
demonstrated by its application to different theoretical scenarios.
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Conlin, Clea Jane. "Integration of the Modern and the Maya: The Mayan Response to Language Shifts in Twentieth Century Guatemala." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/319989.
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Alexander, Carol Anne. "Missional leadership : a Christian response to cultural shifts, authority structures and moral ambiguities in contemporary western society." Thesis, Bangor University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520855.
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Hahl, Oliver (Oliver Douglas). "Subverting value hierarchies : essays on the causes and responses to shifts in demand for authenticity." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82294.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 124-136).
This dissertation includes three essays on the causes and responses to shifts in demand for authenticity. In the first chapter, I answer the question: why do previously cast-off products, practices, or styles abruptly return to popularity? I use a mixed-methods approach in analyzing archival data on the case of venue design in Major League Baseball throughout the twentieth century. My analysis of the baseball industry, including comparison to the professional football industry (NFL) as a counterfactual case, shows that the re-emergence of a once popular, but long-forsaken style arose in response to fan concern over the increased prominence of an ulterior, mercenary motive for performance. I argue and show that this "commitment crisis" invalidated the prevailing popular style, and in its place the retro ballpark style was valued as an expression faithful to the traditional roots of the industry. In the second chapter, I describe one of the causes for shifts in demand for authenticity. In this essay we develop theory that addresses the tendency for high-status actors to be deemed less considerate and more inauthentic than low-status actors. We argue that this tendency stems from two features of the typical status attainment process: (a) the incentive structure, through which the benefits of a high-status position encourage actors to feign capability and commitment, leading to suspicions of inauthenticity; and (b) the interaction process, in which the high-status actor asserts its superiority and another's inferiority, leading to suspicions of inconsiderateness. In the third chapter, I describe and show how firms can effectively reduce penalties for categorical deviance. This essay builds a bridge between the organizational impression management and status perspectives by showing how organizational status influences the effectiveness of anticipatory impression management tools like pre-emptive verbal accounts. We show that high-status firms are better off when they appear assertive in anticipatory impression management signaling - while the opposite is true for middle-status firms. Mediation analysis shows that the same type of framing is perceived differently depending on the status of the restaurant, but that too much perceived effort in framing the deviance will lead to negative results.
by Oliver Hahl.
Ph.D.
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Childress, Lawrence D. "Shifts in Ritual Response to Loss due to Death: An Assessment of Funeral Service Mourning Trends over Time." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2613.
Full textAbstract:
Bereavement, while universal, is experienced and expressed uniquely; it is both ultimate and particular. As the predominant social expression of grief, funerals are purported to be waning and/or transitioning to emergent, less conventional ceremonial forms. In this research, the possible salutary utility of funerals is outlined, and trends relative to the cost, nature (type), and prevalence of funeral services are examined relative to an extant data set from two funeral homes of shared ownership in northeast Tennessee. This data analysis of specific funeral trends in south central Appalachia is juxtaposed against the broader backdrop of current theoretical, clinical, and socio-cultural understandings of bereavement, grief, and mourning.
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Childress, Lawrence D., and Andrea D. Clements. "Shifts in Ritual Response to Loss Due to Death: An Assessment of Funeral Service Mourning Trends over Time." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/7247.
Full textAbstract:
Introduction: As the predominant social expression of grief, funerals have been purported to be waning in occurrence and/or transitioning to emergent, less conventional ceremonial forms. In this research, trends regarding the cost, nature (type), and prevalence of funeral services were examined relative to an extant data set from two funeral homes of shared ownership in northeast Tennessee. The purpose was to verify or refute purported change(s) in the frequency and/or ceremonial emphasis of funerals in the study area. Methods: Anonymized, archival data from two funeral homes in northeast Tennessee (N = 2,581), spanning five years (2008-2012), were evaluated for trends over time with respect to two outcome variables: (1) the presence/absence of a funeral, and (2) the degree of ceremonial emphasis. Results: A binary logistic regression model was fit to the data with annualized time bins (2008 -2012) as predictors of the dichotomous outcome variable (presence/absence of a funeral). An omnibus test of the fitted model against that of a constant/intercept-only model was not statistically significant, indicating that time alone (irrespective of covariates) did not reliably predict whether there would be a funeral ceremony or not [chi square (4) = 6.558, p = .161]. Ceremonial emphasis was then regressed on annualized time bins using a multinomial logistic model without covariates. Model fitting information indicated a statistically significant difference between the final model (including the predictors) and the intercept-only model, suggesting that –in the absence of covariates –annualized time bins did reliably predict degree of ceremonial emphasis [chi square (8) = 149.570, p < .001], with an apparent trend toward decreased ceremonial emphasis. With the covariates of geographic location and retail spending included in the model, and using dummy coding to compare the probability of each degree of ceremonial emphasis to all other categories of emphasis combined, subsequent binomial logistic regressions indicated that although some modest degree of incremental change is apparent, weaving together strands of statistical significance does not result in a meaningful overall explanation of how (and/or why) that change may be occurring. Conclusion: These results do not support the proposition that funerals are declining in their frequency of occurrence, but they do indicate some incremental alterations in the ceremonial emphasis of ritual response to death, as influenced by the passage of time (demarcated annually), economic impacts (relative to retail spending), and geographic location. This research highlights the need for additional empirical investigation into factors explaining possible shifts in mourning (e.g., funerals) as well asother aspects of loss response.
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King, Leighton R. "The Response of Utah Lake's Plant and Algal Community Structure to Cultural Eutrophication." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7631.
Full textAbstract:
Human activities have long had a negative impact on the water quality of freshwater lakes around the world. Utah Lake, located in north-central Utah, has been a subject of such impacts, as the lake experiences recurrent harmful algal blooms during the summer months. Lake warnings and closures have made the public increasingly aware of the ecological and economic impact of these blooms. The objectives of this study were to: 1) compare historical and present-day water quality and ecosystem conditions using environmental data contained in sediment cores, 2) identify whether, and when, Utah Lake transitioned from clearwater to turbid conditions, and 3) incorporate historically-validated lake plant community structure models into establishing forward-thinking lake management targets. The first two objectives will guide lake remediation efforts by providing insight into where lake managers should set our water quality goals and help identify the main driver(s) of eutrophication in Utah Lake. Environmental data from sediment cores indicate a transition in the lake’s recent history, marking a shift to greater phytoplankton dominance, which I attribute to the introduction of invasive common carp around 1881. The third objective provides management and restoration efforts with the water clarity requirements for returning the lake to its historical ecological state.
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Austin, James T. "Goal origin: effects of initial goal origin and shifts in origin on behavioral and subjective responses." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/76090.
Full textAbstract:
Many previous studies have examined the effects of goal attributes on subsequent behavior and performance, with consistently positive findings. However, there are few studies of goal processes, i.e., how reactions to goal origin and subsequent shifts in goal origin are exhibited in behavioral and subjective domains. The present research viewed reactions to goal origins (self-set or assigned) and to shifts in goal origin within a theory of personal control/psychological reactance. In addition, two individual difference constructs, locus of control and Type A Behavior Pattern, were measured to study their relationships with the dependent variables.
A laboratory experiment was conducted to examine several hypotheses drawn from the psychological reactance literature concerning the joint effects of Initial Goal Origin and subsequent Shifted Goal Origin on subjective and behavioral responses. The subjective responses included task and performance satisfaction, goal acceptance, preferences for increasing employee self-control in the workplace, and preferred method of goal-setting. Behavioral measures included two different operational definitions of performance: quantity and goal attainment.
The analyses revealed weak support for the hypotheses. The manipulation check composite revealed that the groups perceived the manipulations along the Initial Goal Origin dimension. There were statistically significant differences for goal acceptance, with the two shift groups displaying a crossover pattern between trial blocks. Simple interaction effect analyses conducted at each level of the Shifted Goal Origin factor revealed a statistically significant interaction between Initial Goal Origin and Trial Blocks for the Shift level only. Goal attainment scores revealed an apparently practical, yet statistically nonsignificant, effect for the three-way interaction of the manipulated factors over trial blocks. Moreover, the pattern of correlations between goals and performance reversed in the predicted direction over trial blocks for the two shift groups. However, there were no significant differences for the factors on the raw performance, satisfaction, or preference variables. The individual difference variables did not make a significant contribution to the prediction of the dependent variables after the effects of group membership were statistically controlled.
The results are discussed in terms of the limitations of the method used, the weak support for the framework which guided the research, and implications for further research and implementation of goal-setting systems in organizations.Ph. D.
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McLean, Kyle Ian. "Aquatic Macroinvertebrate Response to Shifts in Hydroclimatic Variability and Ecohydrological Conditions in Prairie-Pothole Wetlands: Implications for Biodiversity Conservation." Diss., North Dakota State University, 2020. https://hdl.handle.net/10365/31877.
Full textAbstract:
Ecosystem degradation and subsequent biodiversity loss has plagued freshwater environments globally. Wetland ecosystems, such as the depressional wetlands found in the Prairie Pothole Region of North America, have been heavily impacted by historical land-use change and continue to be vulnerable to continued landscape modifications and climate change. Using existing literature, I summarized how recent shifts in climate coupled with historic and contemporary landscape modifications have driven a shift in wetland ecohydrological variability. However, clear trends in biodiversity were often limited by the spatial and temporal resolution of published research.
I used 24 years (1992–2015) of hydrologic and aquatic-macroinvertebrate data from a complex of 16 prairie-pothole wetlands located in North Dakota to relate wetland ecohydrological variability to biodiversity. I used structural equation modeling techniques to test a set of causal hypotheses linking a wetland’s hydrogeologic setting and local climate conditions (i.e., the Wetland Continuum) to changes in hydrology, water chemistry, and biology, with an emphasis on aquatic-macroinvertebrate community response. I then examined the temporal synchrony of aquatic-macroinvertebrate populations to examine the relative importance of landscape-scale controls (e.g., climate, metacommunity dynamics) and wetland-specific controls on community assembly. Using this information, I then quantified among-wetland and amongyear changes in aquatic-macroinvertebrate beta diversity to investigate patterns of biotic homogenization.
I found that spatial and temporal variability in aquatic-macroinvertebrate composition was strongly influenced by ponded-water dynamics. In addition to hydrologic controls, the high levels of temporal coherence of aquatic-macroinvertebrate compositional turnover supported the hypothesis that wetland biodiversity is also dependent on metacommunity dynamics. Analyses of spatio-temporal patterns in beta diversity did not reveal climate driven homogenization of aquatic-macroinvertebrate taxa among wetlands. However, shifts towards more permanently ponded water regimes corresponded with lasting shifts in aquatic-macroinvertebrate community composition. The communities of temporarily ponded wetlands maintained high levels of both temporal and spatial beta diversity. My collective findings indicate that the conservation of aquatic-macroinvertebrate diversity is dependent on the conservation of heterogenous, wellconnected, wetland complexes.