Dissertations / Theses: 'Type of stress state'

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Куан, Фам Дик. "Критерій граничного стану конструкційних матеріалів з врахуванням пошкоджуваності." Doctoral thesis, Київ, 2019. https://ela.kpi.ua/handle/123456789/30096.

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Дисертаційна робота присвячена розробці критерія граничного стану конструкційних матеріалів, які працюють в умовах складного напруженого стану у випадку статичного навантаження з урахуванням пошкоджуваності. Для визначення величини параметра пошкоджуваності використовувалися різні енергетичні підходи, які базуються на зміні фізико-механічних характеристик матеріалів при простих навантаженнях (розтяг та кручення). На основі отриманих експериментальних результатів на різних конструкційних матеріалах, вдосконалено модель опису кінетики накопичення пошкодження, запропонований Бонора, в залежності від рівня пластичної деформації. Отримано залежність параметрів моделі та критерія граничного стану від пружно-пластичних характеристик матеріала. Проведено порівняння отриманих теоретичних значень з експериментальними. Розроблена методика визначення кінетики накопичення пошкодження у випадку кручення циліндричних зразків з врахуванням неоднорідності розподілу деформації в перерізі зразка. На основі підходу Давіденкова-Фрідмана розроблено критерій граничного стану конструкційних матеріалів з врахуванням виду напруженого стану та пошкоджуваності. Представлено порівняння результатів граничного стану, отриманих за розробленим критерієм, експериментальними даними, та іншими методами.

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Foster, Liesel Ann. "Effect of heat stress on six beef breeds in the Zastron District : the significance of breed, coat colour and coat type." Thesis, Bloemfontein : Central University of Technology, Free State, 2010. http://hdl.handle.net/11462/32.

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Arcambal, Angélique. "Effet délétère de l’hyperglycémie sur la fonctionnalité des cellules endothéliales cérébrales et rôle protecteur de polyphénols antioxydants." Thesis, La Réunion, 2019. http://www.theses.fr/2019LARE0004.

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L’hyperglycémie associée au diabète de type 2 induit des complications vasculaires menant à des désordres cérébrovasculaires, comme l’accident vasculaire cérébral. En effet, l’hyperglycémie altère l’intégrité de la barrière hémato-encéphalique, et les cellules endothéliales cérébrales qui la composent sont particulièrement affectées. Le stress oxydant et l’état pro-inflammatoire engendrés par l’hyperglycémie jouent un rôle causal. Dans ce contexte, un intérêt croissant est accordé aux polyphénols d’origine végétale qui pourraient exercer une action antioxydante et anti-inflammatoire protectrice. L’objectif du travail de thèse était d’évaluer l’impact de l’hyperglycémie sur des marqueurs redox, inflammatoires et vasoactifs des cellules endothéliales cérébrales. L’action protectrice de l’insuline en tant qu’hormone hypoglycémiante clé a été explorée. De plus, nous avons étudié le rôle protecteur de polyphénols antioxydants extraits de la plante médicinale Antirhea borbonica de La Réunion. Pour ce faire, un modèle de cellules endothéliales cérébrales murines ainsi qu’un modèle animal d’ischémie cérébrale en condition d’hyperglycémie ont été utilisés. Nos résultats ont montré que l’hyperglycémie a induit un stress oxydant et une réponse pro-inflammatoire contribuant à une altération de la fonction endothéliale. Plusieurs cibles moléculaires ont été identifiées dont les protéines redox Nox4, Cu/ZnSOD, MnSOD, catalase et HO-1 ainsi que les facteurs vasoactifs ET-1, eNOS et NO. L’implication des médiateurs de signalisation Nrf2, AMPK, PI3K, JNK, ERK, p38 MAPK, NFκB et de la cytokine pro-inflammatoire IL-6 a été mise en évidence. L’insuline et les polyphénols ont exercé des effets antioxydants et anti- inflammatoires protégeant la fonction endothéliale. En situation d’ischémie cérébrale, l’hyperglycémie a exacerbé la dérégulation de l’état redox et pro-inflammatoire cérébral, associée à une altération de la barrière hémato-encéphalique. De plus, l’hyperglycémie a aggravé le déficit neurologique, le volume de l’infarctus cérébral et la transformation hémorragique. Les polyphénols ont exercé un rôle protecteur. L’acide caféique et son métabolite circulant, l’acide férulique, détectés au niveau cérébral, pourraient rendre compte de cette action protectrice. Des travaux complémentaires ont montré que les polyphénols protègent également contre l’altération de la fonction de cellules endothéliales aortiques humaines et la perte de vasorelaxation d’anneaux aortiques isolés de souris exposés à une hyperglycémie associée aux lipopolysaccharides de la bactérie Escherichia coli, qui sont des endotoxines liées de manière causale au contexte diabétique. En conclusion, ce travail de thèse a mis en évidence l’effet délétère de l’hyperglycémie sur la fonction endothéliale et le rôle protecteur de polyphénols antioxydants. L’utilisation des modèles expérimentaux développés permettra d’approfondir l’exploration des voies moléculaires impliquées et d’identifier de possibles cibles thérapeutiques innovantes
Type 2 diabetes promotes vascular complications, leading to cerebrovascular disorders such as stroke. Indeed, hyperglycemia alters the blood-brain barrier integrity by deregulating the cerebral endothelial cell function. Oxidative stress and pro-inflammatory response may play a causal role. Thus, the biological effect of plant polyphenols known to exert antioxidant and anti-inflammatory capacities is of high interest. We evaluated the impact of hyperglycemia on the production of redox, inflammatory and vasoactive markers of cerebral endothelial cells, and the protective effect of polyphenols from the medicinal plant Antirhea borbonica from Reunion island. The murine bEnd.3 cerebral endothelial cells and an ischemia-reperfusion mouse model exposed to hyperglycemia were used. Our results demonstrated that hyperglycemia induced an oxidative stress and a pro-inflammatory state, leading to cerebral endothelial dysfunction through the activation of specific signaling molecules. Importantly, polyphenols extracted from Antirhea borbonica counteracted hyperglycemia deleterious effects and protected cerebral endothelial cells. Moreover, hyperglycemia exacerbated oxidative stress and pro-inflammatory state promoting cerebrovascular damages and loss of endothelial barrier integrity in ischemia-reperfusion mice model. Polyphenols exerted antioxidant and anti-inflammatory activities, attenuating cerebrovascular damages. These findings suggest that polyphenols extracted from Antirhea borbonica exerted protective effects on cerebral endothelial cells and an ischemia-reperfusion mouse model against deleterious effects of hyperglycemia

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Kirchen, Patrick. "Steady-state and transient diesel soot emissions : development of a mean value soot model and exhaust-stream and in-cylinder measurements /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18088.

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Krainz, Thomas Edward. "An Analysis of Heat Shock Protein Production in Human Retinal Pigment Epithelial Cells After Different Stress-Induced States." Walsh University Honors Theses / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=walshhonors1524248740945083.

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Obršlík, Petr. "Modelování a statická analýza stropní konstrukce v programu ANSYS." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226805.

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This thesis mainly deals with modeling and static analysis of the ceiling structure in the basic environment of ANSYS. The first part is focused on verifying correctness of the model most stressed parts of the structure with a simple hand-static calculation by the process of stress on a continuous beam. The main part is devoted to modeling composite structure, element types, specifying loads and boundary conditions by ANSYS FEM program. In the end, there are the results of stress and deflection presented, and the structure is evaluated at the ultimate limit state and serviceability limit state.

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Fernandez, Americo Leon. "Tomographic imaging the state of stress." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/20698.

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Carolina, Löf. "Att mäta stress : Adaptering och validering av Dundee Stress State Questionnaire." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-157318.

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Studien hade till syfte att adaptera och validera den multidimensionella stressenkäten Dundee Stress State Questionnaire (DSSQ) som mäter stress utifrån 12 skalor som sammanfaller kring tre högre dimensioner: uppgiftsfokus, ångest och oro. DSSQ adapteras från originalspråket, engelska, till svenska. Tillämpbarheten för den svenska versionen av DSSQ undersöks genom att studera enkätens reliabilitet och validitet samt genom att tillämpa enkäten i två olika kontext, där två olika typer av uppgifter genomförs, ett arbetsminnestest och en polisstudentövning. Sammantaget visade resultatet att den svenska adaptionen av DSSQ har en hög reliabilitet. Dock gick det inte att bekräfta att den svenska adaptionen av DSSQ bibehåller samma faktormodell som originalversionen av DSSQ. Den statistiska analysen visade att de förändringar som identifierats i deltagarnas sinnesstämning delvis stämmer överens med tidigare forskning. Slutsatsen är att fler deltagare behövs för att validera faktormodellen hos den svenska adaptionen av DSSQ och den svenska adaptionen av DSSQ anses vara tillämpar i forskning då den visar på god reliabilitet.
The purpose of this study was to adapt and validate the Dundee Stress State Questionnaire (DSSQ), which measures stress based on 12 scales that cohere around three higher order dimensions: task engagement, distress and worry. DSSQ is adapted from its original language, English, to Swedish. The applicability of the Swedish version of DSSQ is tested by studying the questionnaire's reliability and validity, and by applying the survey in two different contexts, where two different tasks are performed, a work memory task and a police student exam task. Overall, the result showed that the Swedish adaptation of DSSQ has high reliability. However, it was not possible to confirm that the Swedish adaptation of DSSQ maintained the same factor model as the original DSSQ has. The statistical analysis showed the changes identified in the participants' moods partly in lines with previous research. The conclusion is that more participants are needed to validate the factor model for the Swedish adaptation of DSSQ and since the Swedish adaptation of DSSQ shows good reliability, it can be applied in research.

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9

Smith, Alexander Ian. "On the design of finite-state type systems." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/6120/.

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Practical computers have only finite amounts of memory. However, the programs that run on them are often written in languages that effectively assume (via providing constructs such as general recursion) that infinite memory is available, meaning that an implementation of those programs is necessarily an approximation. The main focus of this thesis is on the use of contraction: the ability to use a function parameter more than once in the body of that function (or more generally, to mention a free variable more than once in a term). Unrestricted contraction is a common reason for a language to require unbounded amounts of memory to implement. This thesis looks at a range of type systems, both existing and new, that restrict the use of contraction so that they can be implemented with finite amounts of state, identifying common themes, and explaining and suggesting solutions for common deficiencies. In particular, different restrictions on contraction are seen to correspond to different features of the language’s implementation.

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Lane, Scott Robert. "Stress type and leadership style in the principalship /." view abstract or download file of text, 2000. http://wwwlib.umi.com/cr/uoregon/preview?9977909.

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Thesis (Ph. D.)--University of Oregon, 2000.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 132-138). Also available for download via the World Wide Web; free to University of Oregon users.

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Yelbay, Hasan Ilker. "Determination Of Residual Stress State In Steel Weldments." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610657/index.pdf.

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The purpose of this study is to estimate the residual stress state in steel weldments by using Magnetic Barkhausen Noise (MBN) technique. For obtaining accurate, fast and continuous residual stress measurements a set up for single pass welded plates was designed and used. In order to convert the MBN values to residual stress values a calibration set up was also designed and a procedure for obtaining calibration curves was developed. After welding of low-C steel plates, residual stresses on heat affected zone (HAZ) and parent metal were measured by MBN technique. The results were verified by the hole drilling method. Microstructural investigation and hardness measurements were also conducted.

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Wellons, Stefanie C., and David A. Ph D. Washburn. "Task-Demand Effects on Self-reported Stress State." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/psych_hontheses/9.

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Barsoum, Imad. "The effect of stress state in ductile failure." Doctoral thesis, Stockholm : Hållfasthetslära, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4667.

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Shea, William Thomas. "The state of stress associated with overthrust faulting." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37853.

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Laughton, Lorraine Rosemary. "Teacher-stress in South African state high schools." Thesis, Rhodes University, 1985. http://hdl.handle.net/10962/d1005865.

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Rosell, Richard G. "What type of state homeland security strategy should the state of New Jersey develop?" Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Sep%5FRosell.pdf.

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Thesis (M.A. in Security Studies (Homeland Security and Defense))--Naval Postgraduate School, September 2007.
Thesis Advisor(s): Bellavita, Christopher. "September 2007." Description based on title screen as viewed on October 23, 2007. Includes bibliographical references (p. 53-56). Also available in print.

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Blamire, M. G. "Vortex dynamics in type II superconductors." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372880.

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O'Neill, J. M. "Thermoelastic stress analysis of anisotropic materials." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376642.

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Hotston, Matthew R. "Oxidant stress, phosphodiesterase type 5 expression and erectile dysfunction." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520318.

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Khan, Raja Hameed Ullah. "Characteristics and stress state of Plasma Electrolytic Oxidation Coatings." Thesis, University of Sheffield, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500210.

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Stoddart, S. T. "Flux vortices in type II superconducting films." Thesis, University of Bath, 1994. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239906.

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Savvas, Thrasyvoulos. "Pneumatic stress induced rupture processes in solids." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338444.

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Mansfield, Mark. "Surface stress and reconstructions on metal surfaces." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359866.

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Merazga, Amar. "Steady state and transient photoconductivity in n-type amorphous silicon." Thesis, University of Abertay Dundee, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277887.

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Hill, J. E. "The steady state performance of converter type reactive power compensators." Thesis, Aston University, 1995. http://publications.aston.ac.uk/15322/.

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As a source or sink of reactive power, compensators can be made from a voltage sourced inverter circuit with the a.c. terminals of the inverter connected to the system through an inductive link and with a capacitor connected across the d.c. terminals. Theoretical calculations on linearised models of the compensators have shown that the parameters characterising the performance are the reduced firing angle and the resonance ratio. The resonance ratio is the ratio of the natural frequency of oscillation of the energy storage components in the circuit to the system frequency. The reduced firing angle of the inverter divided by the damping coefficient, , where is half the R to X ratio of the link between the inverter and the system. The theoretical results have been verified by computer simulation and experiment. There is a narrow range of values for the resonance ratio below which there is no appreciable improvement in performance, despite an increase in the cost of the energy storage components, and above which the performance of the equipment is poor with the current being dominated by harmonics. The harmonic performance of the equipment is improved by using multiple inverters and phase shifting transformers to increase the pulse number. The optimum value of the resonance ratio increases pulse number, indicating a reduction in the energy storage components needed at high pulse numbers. The reactive power output from the compensator varies linearly with the reduced firing angle while the losses vary as the square of it.

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Hoffman, Kristin. "Cancer treatment and cellular stress induced type 2 diabetes mellitus." Thesis, Boston University, 2012. https://hdl.handle.net/2144/12422.

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Thesis (M.A.)--Boston University PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Some cancer treatments induce stress responses that activate protective mechanisms and neuregulin expression. In turn, neuregulin activates ErbB receptors, which are responsible for phosphorylating Insulin Receptor Substrates interfering with insulin activity and causing insulin resistance. The effects of neuregulin have been known to enhance development and survival of various tissues by providing nutrients. The activation of ErbB receptors leads to the activation of P13K, which in turn activates serine kinases responsible for phosphorylating IRS-1 and IRS-2. The serine phosphorylated IRS-1 and IRS-2 negatively modulate insulin signaling through the immediate auto-degradation of the serine phosphorylation of IRS, and dissociation of the IR/IRS complex. Furthermore, serine phosphorylated IRS interferes with downstream effectors such as AKT, which are necessary for modulating the glucose transporter, GLUT4. The purpose of this study is to test the hypothesis that neuregulin induced stress pathways alter glucose transport through similar cascades as insulin signaling. A series of experiments were conducted applying variable doses and combinations of neuregulin and insulin to measure the downstream effect on the level of AKT. These applications demonstrated that insulin and neuregulin activate AKT independent from each other through different complimentary mechanisms.

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Nygren, Maria. "Stress in childhood and the risk of type 1 diabetes." Doctoral thesis, Linköpings universitet, Avdelningen för kliniska vetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121066.

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Background: It is still unknown why children develop type 1 diabetes (T1D), although both genetic predisposition and environmental factors seems to be involved. Stress has been suggested as one environmental factor contributing to the development of T1D since the stress hormones may increase the need for insulin or increase insulin resistance. The family is important for the child’s emotional security, development, and regulation of emotions, hence stress among the parent’s may influence the child’s experiences of stress and coping with stressors. Aim: The aim of the current thesis was to evaluate self--‐assessment measurements of psychological stress in the family and to investigate if psychological stress in the family is involved in the development of childhood T1D. Methods: The All Babies in Southeast Sweden (ABIS) study is a prospective cohort study following children born in southeast Sweden between 1997 and 1999. All parents of children born in the region, approximately 21600 were asked to participate. In total, questionnaire data has been obtained from n=16142 (response rate approximately 75%) in some of the six data--‐collections and between 15845 (73%) and 4022 (19%) at each data collection. Psychological stress in the family was measured by questionnaires assessing: Serious life events experienced by the child and the parent, parenting stress, parental dissatisfaction, parental worries, the parent’s adult attachment, and the parents’ social support. Identification of cases with T1D was done through the national register SweDiabKids. At Dec the 31st 2012 had in total 104 (0,64%) children been diagnosed with T1D. Diabetes--‐cases included in the study samples was n=42 and n=58. Results: Parenting stress, parental worries, and size of social support were judged as reliable measurements assessing different aspects of psychological stress in the family, as well as they were all associated to children’s mental health in early adolescence. A serious life event experienced in childhood (measured by checklist at age 5--‐6, 8 and 10--‐ 14 years) was associated with an increase in risk for manifest T1D up to 13--‐15 years of age. None of the variables measuring psychological stress among parents were found to associate with risk of T1D. Conclusions: In addition to a checklist assessing serious life events experienced by the child is self--‐assessment measurements of parenting stress, parental worries and the parent’s social support be useful in large--‐scale studies as proxies for psychological stress of the child. The current study is the first unbiased prospective study that can confirm an association between the experience of a serious life event and increased risk of T1D. The result was independent of the child’s BMI and the parents’ educational level. Our results gives us strong reason to believe that psychological stress caused by serious life events can play a part in the immunological process leading to the onset of T1D.

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Tucker, Matthew Taylor. "Structure-property stress state dependent relationships under varying strain rates." Diss., Mississippi State : Mississippi State University, 2009. http://library.msstate.edu/etd/show.asp?etd=etd-04022009-091044.

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Tucker, Matthew T. "STRUCTURE-PROPERTY STRESS STATE DEPENDENT RELATIONSHIPS UNDER VARYING STRAIN RATES." MSSTATE, 2009. http://sun.library.msstate.edu/ETD-db/theses/available/etd-04022009-091044/.

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In this work, understanding the microstructural effects on stress state and strain rate dependent plasticity, damage, and failure of aluminum and magnesium alloys were examined. Several experimental techniques were employed to implement the test data into a physics-based internal state variable plasticity-damage model. Effects arising from various strain rates, stress states, and material orientations were quantified and discussed within the framework of linking microstructural features to mechanical properties. The method developed for determining structure-property relations was validated by accurately capturing the effects for a variety of materials and loading conditions. The end result is a methodology capable of predicting the onset of damage and failure for a material loaded under complex dynamic conditions.

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Al-Harbi, Naif Mohammad. "Stress amongst male teachers in state schools in Saudi Arabia." Thesis, University of Manchester, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488981.

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There has been increasing professional and public interest in issues related to occupational stress carried out during the last two decades. While a number of studies have been carried out in developed countries on such issues, few studies have been conducted in Saudi Arabia, particularly in the field of education. This study is therefore important because there has been virtually no research that has focused on teacher stress in the country and no study, to-date, has compared teachers' stress at the primary, intermediate, and secondary school stages. This study therefore aims to fill the research gap and to conduct an investigation into an issue that is currently raising serious concerns in the education field.

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Crisan, Romulus Leon. "An investigation into the stress-strain state of case furniture." Thesis, University of Buckingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327158.

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Vuppala, Archana. "Thermal and thermal stress analyses of the state-changing tooling." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1460787.

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Keohane, Stephen Field. "School District Stress Prevention Practices in a Southern U.S. State." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/215.

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The growing recognition that stress is a risk factor for youth health problems has spawned research on school-based stress prevention programs and services. While such programs and services are now available for adoption by schools, there is an absence of data on their use in U.S. schools systems. In the current study, Everett Rogers's diffusion of innovations model provided the theoretical framework for the investigation of school district stress prevention practices in one southern U.S. state. The sample for this quantitative descriptive study consisted of 135 out of 136 active public districts, and 72% of school systems completed and returned the survey (N = 97). Participants were designated school system personnel (83% administrators) who accepted either the e-mail or postal invitation to take part in the study. Descriptive data were gathered on the prevalence and characteristics of stress prevention programs and services for students, and the relationship between school district characteristics and programming and services prevalence was examined via chi-square and Fisher's exact tests. The frequency results indicate that 19% of districts provide programming, 22% provide services, and 23% provide both programming and services to students, and the Fisher's exact test revealed that programming prevalence is highest among urban districts compared to small town/rural school systems (p = 0.12). Recommendations for future research include the study of stress prevention practices with students and school system personnel at the national level. The findings of this study may contribute to the health and welfare of children and adolescents by informing the efforts of school systems to promote the adaptive competence of general student populations.

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Macgregor, Kenneth Waddell. "An investigation into the induced state of stress around inclined boreholes under non-hydrostatic stress conditions." Thesis, University of Strathclyde, 1987. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21493.

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This thesis details research conducted towards investigating the state of stress around inclined boreholes with the ultimate aim of predicting borehole stability and providing realistic estimates of closure stress. Chapter 1 discusses the factors affecting the stability of boreholes and reviews previous research conducted into borehole failure. The mechanics of hydraulic fracturing are reviewed as are methods of predicting fracture gradients. The manner in which closure stress is estimated is also critically reviewed. Chapter 2 describes an initial investigation into the stresses around inclined boreholes using the photoelastic technique of Stress Freezing. Chapter 3 details the laboratory determination of rock properties required for the borehole stability work detailed in Chapter 4. The applicability of the Brinell Hardness test to rock is also examined. Chapter 4 presents a detailed analysis of borehole stability. Failure criteria are developed and applied to estimate the mud weight required to maintain the hole in an elastic condition. To investigate the post-failure stability, existing 'yield zone' equations are modified to allow the effect of rock strength, oil flow rate, in-situ stress and hole angle to be examined. Chapter 5 describes the design and in-house manufacture of the specialised equipment required to measure fracture conductivity in the laboratory, the development of experimental procedures, the various test results and the conclusions drawn from them. Finally, the direct effect of a yield zone on the estimation of closure stress and on proppant selection is examined Chapter 6 summarises the conclusions that may be drawn from the work detailed in this thesis. The chapter also describes possible fields of future research which have been stimulated by the work presented. Two appendices are included, one providing a data-base of proppant properties, the other detailing the results of the application of the data-base to formation samples.

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35

Corcoran, Robin. "The de Haas van Alphen effect in type II superconductors." Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294745.

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36

Wincott, John. "Self-uncertainty and work-related stress: a personal construct investigation of the Type A and Type B behaviourpattern." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1986. http://hub.hku.hk/bib/B31231391.

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37

Nanchen, Stanislas. "Verifying abstract state machines /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17489.

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38

DiGioia, Joseph A. "The "new" new typography? : a critical view of the state of typography /." Online version of thesis, 1995. http://hdl.handle.net/1850/12187.

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39

Mäestu, Jarek. "The perceived recovery-stress state and selected hormonal markers of training stress in highly trained male rowers /." Online version, 2004. http://dspace.utlib.ee/dspace/bitstream/10062/868/5/maestu.pdf.

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40

Cacau, Ronny Glauber de Almeida. "Inverter five levels based on switching cell multi-state type T." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14584.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
Este trabalho apresenta o estudo, projeto e implementaÃÃo de um inversor multinÃvel monofÃsico baseado na cÃlula de comutaÃÃo de mÃltiplos estados tipo T (5L-CCME-T2) para aplicaÃÃes em baixa tensÃo e elevadas correntes. A topologia proposta visa estender a aplicaÃÃo da cÃlula de comutaÃÃo de mÃltiplos estados (CCME) para a estrutura do conversor de trÃs nÃveis tipo T, proporcionando cinco nÃveis na tensÃo de saÃda antes do filtro e, consequentemente, uma reduÃÃo do conteÃdo harmÃnico e maior qualidade da tensÃo de saÃda. Outra caracterÃstica desta topologia Ã a distribuiÃÃo uniforme da corrente total de saÃda entre os semicondutores do conversor, proporcionando menores perdas por conduÃÃo e elevado rendimento. AlÃm disso, Ã possÃvel reduzir o peso e volume dos magnÃticos, uma vez que a frequÃncia de operaÃÃo dos elementos reativos Ã o dobro da frequÃncia de comutaÃÃo dos interruptores. Um estudo teÃrico com anÃlise qualitativa e quantitativa do inversor proposto e metodologia de projeto foi realizado. A estratÃgia de controle implementada tem como objetivo o controle da tensÃo de saÃda e das tensÃes do barramento CC. A tÃcnica de modulaÃÃo empregada Ã a convencional modulaÃÃo por largura de pulso senoidal (SPWM). A validaÃÃo da topologia Ã realizada atravÃs dos resultados de simulaÃÃo e experimentais de um protÃtipo desenvolvido para uma potÃncia de saÃda de 5 kW.
This work presents the study, design and implementation of a multilevel converter based on T - type multi - state switching cell (5L - MSSC - T 2 ) for applications in low voltages and high currents. The proposed topology aims to extend the application of the multi - state switching cell (MSSC) to the structure of the three - level T - type converter, providing five levels in the output voltage before the filter and, consequently, a reduction of the harmonic content and higher output vol tage quality. Another feature of this topology is the uniform distribution of the total output current between the semiconductors of the converter, providing lower conduction losses and high efficiency. Furthermore , it is possible to reduce the weight and volume of magnetics, since the operating frequency of reactive elements is twice the switching frequency of the switches. A theoretical study with qualitative and quantitative analysis of the proposed inverter and the design methodology was performed . The control strategy implemented aims to control the output voltage and the DC bus voltages. The employed modulation technique is the conventional sinusoidal pulse width modulation (SPWM) . The validation of the topology is verified through simulation and exper imental results of a developed prototype for an output power of 5 kW

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Raven, Peter Nigel. "Optical spectroscopy of type II arsenide and antimonide semiconductor superlattices." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296902.

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42

Williams, Walter Ray. "Stress analysis of a glued timber beam." Master's thesis, Mississippi State : Mississippi State University, 2009. http://library.msstate.edu/etd/show.asp?etd=etd-04032009-085801.

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43

Sarshar, Mona. "Explorations in Type-T: Mindset, Flourishing, Psychological Entitlement, Creativity, and Stress." Diss., Temple University Libraries, 2017. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/476413.

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Educational Psychology
Ph.D.
Type-T behavior is a term coined by F. Farley (see McGraw-Hill, Concise Dictionary of Modern Medicine, 2002) to reflect individual differences in risk-taking and thrill-seeking (T) behavior. This study was designed to explore and expand the understanding of Type-T behavior in relation to other individual differences of current psychological and educational interest, namely flourishing, mindset, psychological entitlement, creativity/innovation, and stress. The study used both a college student sample and a non-college adult sample to investigate whether the type of sample makes a difference in research of this type. The inclusion of the latter sample was prompted by the need to identify and examine psychological processes beyond the college undergraduate, given the over-representation of the latter participants in psychological research. Four hundred seventy- two participants including two hundred forty-eight students and two hundred twenty-four non-college adults completed an online survey designed to measure the aforementioned personality and psychological variables. Results of multiple regressions with pairwise deletion of missing data showed that college students and non-college adults with high risk-taking/thrill-seeking behaviors (Big T) reported higher levels of flourishing. Big Ts were also more self-entitled. Younger participants reported higher levels of Type-T than older participants. Additionally, males reported higher levels of Type-T behaviors than did females. The results of the Pearson correlations in non-college samples showed significant positive correlations of Type-T scores with malleable mindset, flourishing, and age; Type-T was found to be negatively correlated with fixed mindset, while the correlation for the college sample was non-significant. Those who reported higher levels of risk-taking/thrill-seeking behaviors were more likely to report a malleable mindset rather than a fixed mindset. The results of Pearson correlations among the scales in the college sample were somewhat different from the non-college sample. Type-T was significantly associated with entitlement, malleable mindset, flourishing, creativity, and gender. For the total sample, respondents with higher Type-T scored higher on entitlement, had a lower level of fixed mindset but a higher level of malleable mindset, a higher level of flourishing, more creativity, were younger, and were more frequently males. This study has expanded our understanding of Type-T behavior, enriching its description, bringing important new constructs into the discussion (e.g. mindset, self-entitlement, flourishing), and discerning provocative new relationships among some of the studied non-T variables themselves. If risk-taking and the responsiveness to change are signal qualities in human innovation and progress, then a focus on the personal representation of these features as in Type-T may be one key to personal and societal success in a rapidly evolving world.
Temple University--Theses

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Jordon, James Brian. "DAMAGE AND STRESS STATE INFLUENCE ON BAUSCHINGER EFFECT IN ALUMINUM ALLOYS." MSSTATE, 2006. http://sun.library.msstate.edu/ETD-db/theses/available/etd-04172006-133053/.

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In this work, the Bauschinger effect is shown to be intimately tied not only to plasticity but to damage as well. The plasticity-damage effect on the Bauschinger effect is demonstrated by employing different definitions (Bauschinger Stress Parameter, Bauschinger Effect Parameter, the Ratio of Forward-to-Reverse Yield, and the Ratio of Kinematic-to-Isotropic Hardening) for two differently processed aluminum alloys (rolled and cast) in which specimens were tested to different prestrain levels under tension and compression. Damage progression from second phase particles and inclusions that were generally equiaxed for the cast A356-T6 aluminum alloy and elongated for the rolled 7075 aluminum alloy was quantified from interrupted experiments. Observations showed that the Bauschinger effect had larger values for compression prestrains when compared to tension. The Bauschinger effect was also found to be a function of damage to particles/inclusions, dislocation/particle interaction, the work hardening rate, and the Bauschinger effect definition.

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Schultz, Heather Rae. "The Effects of Mindful Coloring on State Mindfulness, Anxiety, and Stress." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1504005638593573.

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46

Sandström, Daniel. "Analysis of the virgin state of stress at the Kiirunavaara mine." Licentiate thesis, Luleå, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-16968.

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The mining production in Kiruna is heading towards larger depth and it is necessary to prepare for the next generation of underground facilities and new mining methods below the current main level. An important issue is the increasing rock stresses, which follows the ever-increasing depth of mining. This may result in instability of drifts, ramps, shaft and other facilities. The objective of this thesis is to clarify the stress situation in the mine and to state a relationship that could be used for rock mechanical analysis. The first part of the thesis is an appraisal of the results from the rock stress measurements carried out during the 1980's and 1990's. The measured state of stress shows a large variation, which depends on the influence of the mining production, measuring errors, and the heterogeneous nature of the rock mass. Even though, the stress measurements clearly affected by the mining production is sorted out, the variation remains. This means that the stress state in Kiirunavaara is still difficult to interpret. In order to increase the understanding of the natural variation, a literature review and analyses of the stress distribution in the rock mass is given. Because of this uncertainty, the second part presents another approach of handling the problems with the large scatter in the measured state of stress. By doing conceptual numerical analyses and probabilistic sensitivity analyses of underground constructions, the parameters affecting the behavior of the rock mass are studied. The analyses shows that the significance of the variation of the stress state is less than the significance of many other parameters like the stiffness and the strength of the rock mass. The recommendations is therefore, that a geomechanical model of the mine should be developed including for instance, the spatial variation of parameters like Young's modulus and strength of intact rock and joint parameters like number of joint sets, orientation, frequency and filling material.

Godkänd; 2003; 20070218 (ysko)

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47

Джус, А. П. "Розвиток наукових основ забезпечення працездатності обладнання при транспортуванні стиснутого природного газу." Thesis, Івано-Франківський національний технічний університет нафти і газу, 2016. http://elar.nung.edu.ua/handle/123456789/4786.

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Дисертація присвячена вирішенню важливої науково-прикладної проблеми забезпечення працездатності обладнання при реалізації технологічних процесів транспортування стиснутого природного газу морськими акваторіями. В роботі встановлено закономірності впливу схем та швидкостей реалізації процесу завантаження ємностей високого тиску, виконаних у вигляді рухомого трубопроводу, на їх напружено-деформований стан. Досліджено умови формування кільцевих тріщин в композитному підсиленні ємностей комбінованого типу, особливості взаємодії підсилення і металевого лейнера в процесі експлуатації та оцінено вплив наявності тріщин на формування напружено-деформованого стану металевих лейнерів з врахуванням можливості їх корозійного пошкодження. Дістали подальший розвиток теоретико-методологічні засади комплектування технологічних морських транспортних засобів обладнанням для підготовки та стиснення газу, запропонований новий підхід до оптимізації процесів розвантаження морських транспортних засобів в існуючу газотранспортну інфраструктуру. Розроблено метод та засоби оцінки працездатності обладнання для транспортування стиснутого природного газу з врахуванням фактичного технічного стану та навантажень, зумовлених особливостями реалізації технологічних процесів. Запропоновано новий критерій досконалості для порівняльної оцінки ємностей різних типів і робочих тисків, який визначається відношенням маси ємності до об’єму газу, що перевозиться в ній, приведеного до нормальних умов.
Диссертация посвящена решению важной научно-прикладной проблемы обеспечения работоспособности оборудования при реализации технологических процессов транспортировки сжатого природного газа путем разработки метода оценки его технического состояния, совершенствования конструкции грузовых емкостей и формирования методологических основ комплектования оборудованием технологических барж и разгрузочных терминалов. Установлены закономерности влияния термодинамических процессов на формирование температурных нагрузок оборудования для транспортировки сжатого природного газа и получены количественные зависимости, учитывая которые можно предотвратить потерю работоспособности емкостей вследствие выхода их рабочих температур за пределы допустимых значений. Для емкостей высокого давления, выполненных в виде подвижного трубопровода, установлены закономерности влияния способов и скоростей реализации процесса загрузки на их напряженно-деформированное состояние, указывающие на необходимость оценки долговечности элементов соединения линейных участков с учетом двухчастотности процесса погрузки. Исследованы условия формирования кольцевых трещин в композитном усилении емкостей комбинированного типа. Доказано, что напряженно-деформированное состояние металлического лейнера возле кольцевых трещин, приближенных к днищам, характеризуется склонностью к росту напряжений и увеличению вероятности разрушения. Предложен метод оценки работоспособности оборудования для транспортировки сжатого природного газа с учетом нагрузок, обусловленных особенностями реализации технологических процессов, и фактического технического состояния. Для его определения на базе высокочастотного индуктивного датчика создана автоматизированная система контроля с возможностью воспроизведения участков потерь металла в трехмерном виде. Разработана технология изготовления многополостного сосуда высокого давления повышенной работоспособности с использованием композитных и стальных труб. Специально введенным для сравнительной оценки емкостей различных типов и рабочих давлений критерием совершенства, который определяется отношением массы емкости до объема газа, приведенного к нормальным условиям, обоснована целесообразность ее использования в виде длинномерной конструкции, ограниченной параметрами морского транспортного средства. Предложен новый подход к оптимизации процессов разгрузки морских транспортных средств в существующую газотранспортную инфраструктуру с использованием двух ветвей соединительного газопровода. Соблюдение рекомендаций по режимам работы разгрузочных терминалов обеспечивает разгрузку из морских транспортных средств до 80% газа без введения в действие компрессорного оборудования, а также минимизирует влияние особенностей технологических процессов на работоспособность магистральных газопроводов. Комплексный учет теоретических и экспериментальных исследований влияния технологических процессов загрузки и разгрузки морских транспортных средств на формирование напряженно-деформированного состояния элементов оборудования позволил разработать меры обеспечения его работоспособности при транспортировке сжатого природного газа.
The dissertation is devoted to solving the important scientific and applied problem of equipment performance assurance in the implementation of compressed natural gas transportation processes across offshore zones. The paper established the influence patterns of charts and speeds for feeding process of the high-pressure reservoirs, constructed in the form of movable pipelines, onto their strain-stress state. The conditions of ring cracks formation in composite reinforcement of combined type reservoirs, peculiarities of reinforcement coupling with metallic liner in operation, were investigated, the impact of cracks presence for metallic liners strain and stress state formation, considering the possibility of corrosion damage, were assessed. The theoretical and methodological principles of processing offshore transport facilities, stocking with equipment for gas treatment and loading, got the further development, the new approach for unloading operations optimization of offshore transport facilities into existing gas transport infrastructure was proposed. The method and operability tools for compressed gas transportation, taking into consideration the existing technical state and loading due to the processes implementation peculiarities were developed. The new criterion of excellence for comparative assessment of various type and operating pressure reservoirs, determined by the ratio of the mass of the reservoir to the volume of gas to be transported in it, reduced to normal conditions, was proposed.

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48

Creighton, Jennifer Renee. "Yogic Breathing for Post-Traumatic Stress Disorder: Designing an Application to Supplement Learning and Overcome a Stress State." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/344450.

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Many who suffer with Post-Traumatic Stress Disorder (PTSD) fear the stigma associated with seeking treatment. Often the stigma even prevents sufferers from reaching out for support, resources, or education. The purpose of this project was to design an application (app) to bridge the gap between patient and provider by supplementing patient learning and teaching a yogic breathing technique to overcome an acute stress state. To accomplish this, an extensive literature review sought to determine the viability of pairing complimentary alternative methods (CAM) of treatment with application-based interventions. A specific aim also included evaluation of an app available on the market using industry standard tools, the Systems Usability Scale and HONcode measures, to determine areas for improvement. Applications can present a viable alternative to reaching patients who are unable or refuse to seek provider assistance. There are few apps to address mental health concerns; furthermore, patients may not use applications because they fear bias within the content or the lack of a quality product. Of the applications available on the market created by professional providers, there is a noted lack of aesthetics, user-friendliness, and reliability. To address aesthetics and user-friendliness, the new application is module based and incorporates basic web-application design principles. To address reliability, the new application answered all the objective criteria in the HONcode and scored higher on the subjective Systems Usability Scale than a leading app on the market, as evaluated by the project lead. This application presents an opportunity to determine the success of pairing patient education and CAM with technology. While it is beyond the scope of this project, the new application is ready for a pilot testing to obtain feedback on the content, structure, and usability, before launching on GoogleApps™ for open access.

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Hartnett, S. J. "Uniaxial stress/DLTS studies on deep level defects in n-GaAs." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361362.

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Maier, Paul Martin. "Vasopressin und Stress beim Wiederkäuer /." [S.l.] : [s.n.], 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10662.

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Dissertations / Theses on the topic 'Type of stress state'

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