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Is There a Relationship Among Overall Nutritional Quality Index, Carbon Footprint and the Price of Food?Lin, Qiumei 14 December 2012 (has links)
This study explores the relationship among the overall nutritional quality index (ONQI), the carbon footprint and price of 90 different foods. The ONQI and carbon footprint measure the healthiness and environmental impact of a food, respectively. Two models are estimated. The first is a hedonic model of the food price and two characteristics: ONQI and carbon footprint. A positive relationship between price and carbon footprint is found, implying higher priced foods have a larger environmental impact. The second model is a regression of ONQI on price and carbon footprint. A negative, non-linear relationship between ONQI and carbon footprint is found. This implies there is a complementary relationship between the healthiness of food and its environmental impact. Both models show that healthier food is also higher priced. This could explain why poorer consumers are less healthy than richer consumers, and why taxing food would disproportionately impact the health of the poor.
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Psychometric Properties of the Pittsburgh Sleep Quality Index (PSQI) in a Cohort of Peruvian Pregnant Women.Zhong, Qiu-Yue, Gelaye, Bizu, Sánchez, Sixto E, Williams, Michelle A 08 1900 (has links)
STUDY OBJECTIVES:
We sought to evaluate the construct validity and factor structure of the Spanish-language version of the Pittsburgh Sleep Quality Index (PSQI) among pregnant Peruvian women.
METHODS:
A cohort of 642 women were interviewed at ≤ 16 weeks of gestation. During interview, we ascertained information about lifestyles, demographics, sleep characteristics, and mood symptoms. Stress induced sleep disturbance, depressive symptoms, and anxiety symptoms were evaluated using the Ford Insomnia Response to Stress Test (FIRST), Patient Health Questionnaire-9 (PHQ-9), and Generalized Anxiety Disorder-7 (GAD-7) assessment scales, respectively. Consistency indices, exploratory and confirmatory factor analyses, correlations, and logistic regressions were used.
RESULTS:
Both exploratory and confirmatory factor analyses indicated a three-factor solution: sleep quality, sleep efficiency, and sleep medication. We observed significantly positive correlations of the PSQI with the FIRST (0.42), the PHQ-9 (0.49), and the GAD-7 (0.46). Poor sleepers (PSQI global score > 5) had significantly increased odds of experiencing stress-induced sleep disturbance (odds ratio, OR = 3.57; 95% CI: 2.40, 5.31), depression (OR = 5.48; 95% CI: 3.58, 8.37), and generalized anxiety disorder (OR = 4.57; 95% CI: 3.08, 6.76).
CONCLUSION:
The Spanish-language version of the PSQI instrument was found to have good construct validity among pregnant Peruvian women. Consistent with some other studies, the PSQI was found to have a three-factor structure. Further assessment and validation studies are needed to determine whether the three, factor-specific scoring of the PSQI is favored over the PSQI global score in diverse populations.
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The views of physicians on health care qualityLockhart, Wallace Stewart 02 April 2007
Objectives: There are four primary goals for this research project: <ol><li>To develop an objective index of health care quality which represents, in the best practical way, a comprehensive range of services provided at the health region level.
<li>To develop a comparable measure representing physician assessments of health care quality, and compare this measure with the objective index. <li>To develop an understanding of the relationships between physician ratings on the workplace issues of professional autonomy, stress, sense of equity and satisfaction and their views on health care quality.<li>Based on the understanding of this research, provide recommendations to health care policy makers about the use of both physician viewpoints and objective measures of quality.</ol> Background: Health care in Canada has grown and evolved from a relatively simple offering of services, provided primarily by doctors and hospitals, to a complex conglomeration of programs and services, provided by a loose network of both public and private providers. As a result, physicians are under pressure to adapt to these changes and a power struggle which has always pitted physicians against policy makers. In dealing with changes to the health care system the use of statistics and evidence is gaining prominence as the basis for policy decisions, in addition to the less formal tools of rhetoric and politics.<p>Design: Data from the 2004 Canada-wide survey Emerging Issues in the Work of Physicians is compared to a single index score of health care quality based on objective data from the annual Health Indicators Report published by Canadian Institute of Health Information and Statistics Canada (2005). These reports include a number of measures of quality and access to health care by health region and by province, using mandatory standardized data collection and reporting procedures. <p>Measures: Nine reliable measures of health care quality were selected from the Health Indicators Reports for inclusion in the index: 30 day AMI risk; 30 day stroke risk; AMI readmission risk; asthma readmission risk; ACSC rate; hysterectomy readmission rate; prostatectomy rate; in-hospital hip fracture rate; and C-section rate. Index scores were developed for each of the measures, which were then assigned weights based on importance, resulting in a single overall index of health care quality. These scores are compared to a similar index score which is based on physician views on quality, as collected in the national survey.<p>Results: Physician views on health care quality are aligned with the objective data when examined on an aggregate basis. However, there is a high degree of variability in physician responses which results in differences when examining the data on regional or individual bases. In addition, physician views on quality are influenced by factors in their work lives including autonomy, stress, equity and satisfaction. On each of these factors, those reporting high and low levels will generally over and under-rate health care quality as compared to those reporting moderate levels.<p>Discussion: As policy makers make decisions on how to shape the future of health care, they must grapple with conflicting viewpoints of different stakeholder groups, and they must decide on the degree to which they rely on evidence (in the form of objective data) versus influence (as exerted by physicians and/or other stakeholder groups). This research shows that, while physician views on how well the health care system is performing are generally aligned with the objective data, those opinions vary greatly between individuals, and are influenced by work related factors including autonomy, stress, equity and satisfaction.
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The views of physicians on health care qualityLockhart, Wallace Stewart 02 April 2007 (has links)
Objectives: There are four primary goals for this research project: <ol><li>To develop an objective index of health care quality which represents, in the best practical way, a comprehensive range of services provided at the health region level.
<li>To develop a comparable measure representing physician assessments of health care quality, and compare this measure with the objective index. <li>To develop an understanding of the relationships between physician ratings on the workplace issues of professional autonomy, stress, sense of equity and satisfaction and their views on health care quality.<li>Based on the understanding of this research, provide recommendations to health care policy makers about the use of both physician viewpoints and objective measures of quality.</ol> Background: Health care in Canada has grown and evolved from a relatively simple offering of services, provided primarily by doctors and hospitals, to a complex conglomeration of programs and services, provided by a loose network of both public and private providers. As a result, physicians are under pressure to adapt to these changes and a power struggle which has always pitted physicians against policy makers. In dealing with changes to the health care system the use of statistics and evidence is gaining prominence as the basis for policy decisions, in addition to the less formal tools of rhetoric and politics.<p>Design: Data from the 2004 Canada-wide survey Emerging Issues in the Work of Physicians is compared to a single index score of health care quality based on objective data from the annual Health Indicators Report published by Canadian Institute of Health Information and Statistics Canada (2005). These reports include a number of measures of quality and access to health care by health region and by province, using mandatory standardized data collection and reporting procedures. <p>Measures: Nine reliable measures of health care quality were selected from the Health Indicators Reports for inclusion in the index: 30 day AMI risk; 30 day stroke risk; AMI readmission risk; asthma readmission risk; ACSC rate; hysterectomy readmission rate; prostatectomy rate; in-hospital hip fracture rate; and C-section rate. Index scores were developed for each of the measures, which were then assigned weights based on importance, resulting in a single overall index of health care quality. These scores are compared to a similar index score which is based on physician views on quality, as collected in the national survey.<p>Results: Physician views on health care quality are aligned with the objective data when examined on an aggregate basis. However, there is a high degree of variability in physician responses which results in differences when examining the data on regional or individual bases. In addition, physician views on quality are influenced by factors in their work lives including autonomy, stress, equity and satisfaction. On each of these factors, those reporting high and low levels will generally over and under-rate health care quality as compared to those reporting moderate levels.<p>Discussion: As policy makers make decisions on how to shape the future of health care, they must grapple with conflicting viewpoints of different stakeholder groups, and they must decide on the degree to which they rely on evidence (in the form of objective data) versus influence (as exerted by physicians and/or other stakeholder groups). This research shows that, while physician views on how well the health care system is performing are generally aligned with the objective data, those opinions vary greatly between individuals, and are influenced by work related factors including autonomy, stress, equity and satisfaction.
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Índice de qualidade das águas na parte baixa da bacia hidrográfica do rio Trussu, Ceará / Ndex of water quality in low part of the river basin Trussu, CearáPalácio, Helba Araújo de Queiroz January 2004 (has links)
PALÁCIO, Helba Araújo de Queiroz. Índice de qualidade das águas na parte baixa da bacia hidrográfica do rio Trussu, Ceará. 2004. 97 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza-CE, 2004. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-07-05T16:29:02Z
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Previous issue date: 2004 / The main goal of this work was to evaluate the water quality in the Trussu River valley. The Trussu River drainage an area of 1,590 km2 and it is a tributary of left site of Jaguaribe River. This region located in Iguatu County, Ceará, Brazil. Drainaged waters are stored at Roberto Costa (Trussu) dam, which deliver water to human consume, livestock and irrigation in the last 20 km of the valley. In this study, a data reduction technique, Principal Componente Analysis (PCA), was used to develop a water quality index. Water samples were carried out every month from sept./2002 to mar./2004 in nine sample stations spread out the Trussu River area. Five of them are sited along the river and other four are located in shallow wells. It was analyzed the following variables: pH, EC, Na+, Ca+2, Mg+2, K+, Cl-, HCO3 -, PO4 -2, NH+ 4, NO3 - , SO4 -2 and SAR. The use of PCA technique has allowed the identification of variables that explain higher percentage of total variance. Also, PCA technique allowed the reduction of the 13 variables to two significant components that explain 83.44% of the total variance. The first one, PC1, (account for 64.10% of the variance) which can initially assigned to water mineralization. The second one, PC2, (account for 19.34% of the variance) is built from variables indicative of man-made effect. In a second step, these parameters were applied to develop a water quality index (WQI). The WQI showed up a good adequacy to evaluate the water quality in Trussu River valley. Also, results pointed up that water quality to shallow well has a high spatial variability. Sampling stations 8 and 9 registered the lowest WQIs and they were inapt to human consume, where WQIs were lowed than 30. Surface waters presented as suitable to human consume during the studied period with WQIs average over to 80. the anthropeic degradation was observed in sampling stations 6 and 7, where WQIs are lower than other stations sited in up land. These results can be explained by a bigger demographic concentration close to stations and the lack of sewer in the region. / O presente trabalho foi desenvolvido com o propósito de avaliar a qualidade das águas para aparte baixa da bacia hidrográfica do rio Trussu, localizada no município de Iguatu-CE. Este rio, que é afluente da margem esquerda do rio Jaguaribe, e drena uma área de 1590 km2. Suas águas são barradas pelo açude Roberto Costa (Trussu), o qual pereniza 20 km de rio com a finalidade de fornecer água para o consumo humano e a agropecuária do vale do Trussu. Neste estudo foi desenvolvido um índice de qualidade de água, utilizando a técnica de estatística multivariada, denominada análise da componente principal. Os dados empregados neste trabalho foram coletados mensalmente de setembro de 2002 a fevereiro de 2004, em cinco estações amostrais distribuídas ao longo do trecho perenizado e quatro poços rasos próximos ao rio Trussu. O estudo de qualidade de água considerou as seguintes variáveis físico-químicas: pH, condutividade elétrica, cálcio, magnésio, sódio, potássio, bicarbonato, fosfato, cloreto, amônio, nitrato, sulfato e relação de adsorção de sódio. A técnica da análise da componente principal (ACP) foi aplicada com o objetivo de selecionar as variáveis mais significativas para a variabilidade total dos dados. A ACP proporcionou a redução de 13 variáveis em duas componentes que explicaram 83,44% da variância total. A primeira componente (contendo 64,10% da variância) expressa o processo do intemperismo; podendo ser identificada como uma componente de mineralização das águas do rio Trussu. A segunda componente (19,34% da variância) é alusiva à contaminação orgânica; indicando uma componente representativa da ação antrópica. Em uma segunda etapa do estudo, estes parâmetros foram utilizados para desenvolver um índice de qualidade de água (IQA), para classificar este recurso na região. O IQA apresentou uma boa adequação para avaliar a qualidade das águas no vale do Trussu. Os resultados, também mostraram uma grande variabilidade espacial na qualidade das águas subterrâneas, existindo pontos em que a água é inadequada ao consumo humano (estações amostrais 08 e 09), com um IQA inferior a 30. As águas superficiais mostraram-se adequadas ao consumo humano ao longo de todo o período estudado, apresentando média de IQA acima de oitenta. A degradação antrópica da qualidade das águas superficiais pode ser claramente observada nas estações amostrais 06 e 07, onde o IQA é inferior às demais estações a montante. Esta menor qualidade de água pode ser atribuída à maior concentração demográfica da região e à ausência de saneamento básico.
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An Index of Biotic Integrity for Macroinvertebrates and Salamanders in Primary Headwater Habitat Streams in OhioMoore, Edward L., Jr. 15 January 2010 (has links)
No description available.
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L'utilisation de benzodiazépines et la qualité du sommeil des personnes âgées du QuébecBéland, Sarah-Gabrielle January 2009 (has links)
Plusieurs études ont montré que la prévalence des troubles du sommeil dans la population âgée de 65 ans et plus se situait entre 25 et 50%. Les benzodiazépines sont les médicaments les plus souvent prescrits pour traiter les problèmes de sommeil. La prévalence de la consommation de benzodiazépines chez les personnes âgées se situe à près de 25%. Le Collège des Médecins du Québec préconise une utilisation de benzodiazépines pour une durée maximale de trois mois.Plusieurs études rapportent toutefois que la durée moyenne de consommation de benzodiazépines est bien supérieure à la période recommandée et on possède peu d'information sur l'efficacité populationnelle à long terme de ces médicaments pour réduire les troubles du sommeil. Le but de ce mémoire était d'étudier le lien entre la consommation de benzodiazépines et la qualité de sommeil chez les personnes âgées de plus de 65 ans vivant à domicile au Québec. Pour atteindre cet objectif, deux études ont été réalisées et les résultats sont présentés sous forme d'articles. La première étude visait à documenter le lien entre la consommation de benzodiazépines et la qualité globale du sommeil ainsi que ses différentes composantes. La deuxième avait pour but d'étudier le lien entre la consommation de benzodiazépines et l'évolution de la qualité du sommeil sur une période de 12 mois. Pour répondre à ces objectifs, les données utilisées provenaient de l'Enquête sur la Santé des Aînés (ESA). L'ESA utilise un devis longitudinal avec entrevue à deux temps de mesures à un an d'intervalle auprès de 2798 sujets. Dans le cadre de la première étude, nous avons utilisé le premier temps de mesure de l'ESA et la consommation médicamenteuse était auto-rapportée par l'ensemble des participants. Pour la deuxième étude, nous avons étudié un sous-échantillon de 892 personnes participant aux deux temps de mesure de l'ESA et pour lesquelles les données sur la délivrance de benzodiazépines étaient disponibles via le registre sur la consommation médicamenteuse de la régie de l'assurance maladie du Québec. La qualité du sommeil était auto-rapportée à l'aide du questionnaire Pittsburgh Sleep Quality Index (PSQI). Des analyses de modélisation d'équations structurales ont été effectuées à l'aide du logiciel Lisrel 8,8. Le premier article montre que les facteurs les plus fortement associés à une mauvaise qualité de sommeil chez les personnes âgées sont la consommation de benzodiazépines et le sexe féminin. D'autre part, la consommation de benzodiazépines était associée de façon similaire à chacune des six composantes de la qualité du sommeil mesurées à l'aide du PSQI exception faite de la composante liée aux dysfonctionnements diurnes. Le deuxième article montre que la fréquence de consommation de benzodiazépines durant les 12 mois suivant le temps 1 de l'enquête ESA est associée à une diminution de la qualité de sommeil chez les gens qui ne souffraient pas de troubles du sommeil initialement. Chez les personnes âgées qui souf fraient d'une mauvaise qualité de sommeil au départ, le sommeil est de meilleure qualité après un an. Cette amélioration de la qualité du sommeil est toutefois moins importante chez les consommateurs de benzodiazépines que chez les personnes âgées ne consommant pas ces médicaments. Cette étude suggère donc un effet néfast de la consommation de benzodiazépines sur la qualité de sommeil des personnes âgées. Nous proposons que d'autres études soient réalisées auprès de sujets nouvellement exposés aux benzodiazépines (cas incidents) afin de vérifier la relation délétère suggérée par nos travaux entre la consommation de benzodiazépines à long terme et la qualité de sommeil chez les personnes âgées.
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Shiftwork, sleep disturbances and cardiometabolic risk in female hospital employeesLajoie, PASCALE 25 September 2013 (has links)
Background: Epidemiologic evidence supports the association between shiftwork and the development of cardiovascular disease. Sleep disturbances are associated with a variety of adverse cardiometabolic outcomes and they may lie on the causal pathway between the exposure to shiftwork and cardiovascular disease.
Objectives: 1) To describe sleep quality in a group of shift-working and day-working female hospital employees; 2) To determine the association between shiftwork status and sleep disturbances in this group and to determine the effect of lifetime exposure to shiftwork on current sleep disturbances; and 3) To explore whether sleep disturbances mediate the relationship between shiftwork and cardiometabolic risk.
Methods: A cross-sectional study was conducted among female hospital employees: participants were 132 women working only during the day, and 98 women who worked a shift schedule of two 12-hour days, followed by two 12-hour nights and five days off. Sleep quality was assessed with the Pittsburgh Sleep Quality Index questionnaire. The primary outcome of interest was the metabolic syndrome defined in accordance with the 2009 Joint Interim Studies consensus statement.
Results: Shiftwork was associated with poor sleep latency (odds ratio (OR)= 2.08 95% CI: 1.11-3.92), poor sleep efficiency (OR=2.35 95% CI: 1.21- 4.54), and poor global sleep quality (OR=1.88 95% CI: 1.02-3.49), while the impact of past shiftwork history was inconclusive. The OR for the association of shiftwork with the metabolic syndrome was 2.00 (95% CI: 0.89-4.51), and there was no evidence of mediation by sleep disturbances in the relationship of shiftwork and the metabolic syndrome.
Conclusion: In this study, a rapid forward rotating 2-shift system is associated with self-reported poor sleep quality, while the long-term effects of sleep disturbances on cardiometabolic risk requires further study. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2013-09-24 21:16:38.768
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Vandens kokybės indeksas Šventosios upės baseinui / Water quality index for the Šventoji river basin, eastern LithuaniaZareckas, Mindaugas 16 June 2014 (has links)
Vandens tarša išlieka viena pagrindinių aplinkosaugos problemų. Upių ir ežerų vandens kokybė Lietuvoje yra nuolat stebima, vykdomas valstybinis monitoringas. Siekiant išaiškinti Šventosios baseino upių vandens kokybę ir jų kaitą, darbe buvo pritaikytas vandens kokybės indeksas. Šiam tikslui buvo panaudoti Šventosios baseino valstybinio monitoringo 1992 – 2012 m duomenys. Vandens kokybės indekso įvertinimui panaudoti šie parametrai: skendinčių medžiagų kiekis, pH, ištirpęs O2, BDS7, NO3-N, N bendras, P04-P, P bendras, Ca, Mg, SO4, Pb, Hg ir koliforminės bakterijos. Nustatyta, kad praeityje Šventosios upę ir jos intakus daugiausia teršė koliforminės bakterijos, tuo tarpu pastaruoju metu vyrauja fosforo ir azoto junginių tarša. Blogiausi vandens kokybės indeksų vidurkis nustatytas Vyžuonos upėje žemiau Utenos – 53,1 balo, o geriausias Šventojoje ties Sabaliūnais - 83,5 balai. / Water pollution is one of the most important problems in environmental protection. Water quality of Lithuanian rivers and lakes is constantly observed and national monitoring is being performed. In order to find out the Šventoji river basin water quality and its long-term changes, water quality index was applied in the work. To reach this goal, the Šventoji river basin national monitoring data of 1992-2012 years were used. To evaluate water quality index, the following parameters were applied: suspended substance, pH, dissolved O2, BDS7, NO3-N, N total, PO4-P, P total, Ca, Mg, SO4, Pb, Hg and coliform bacterias. Results of the research revealed that the Šventoji river and its tributaries had been polluted with coliform bacterias in the past, while recently pollution of phosphorus and nitrogen have dominated. The worst water quality indexes average determined in the Vyžuona below Utena – 53,1 points, and the best is in the Šventoji at Sabaliūnai – 83,5 points.
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The Relationship Between High-Cycle Fatigue and Tensile Properties in Cast Aluminum AlloysOzdes, Huseyin 01 January 2016 (has links)
Cast aluminum alloys are common in automotive and aerospace applications due to their high strength-to-density ratio. Fracture data for cast aluminum alloys, such as fatigue life, tensile strength and elongation, are heavily affected by the structural defects, such as pores and bifilms. There have been numerous studies in which either fatigue performance or tensile deformation were characterized and linked to casting defects. However, a comprehensive study that correlates tensile and fatigue properties has not been reported. The present study is motivated to fill this gap. The main objective of the investigation is to analyze the link between tensile and fatigue performance of commonly used cast aluminum alloys, and determine whether fatigue performance of cast aluminum alloys can be predicted. To accomplish this task, four research questions were developed: (i) how well do equations developed to account for mean stress effects perform in cast aluminum alloys, especially in datasets with various levels of structural quality, (ii) is the strong correlation between fatigue life and structural quality index obtained from tensile data reported for A206 alloy castings applicable to other aerospace and automotive casting alloys, (iii) how do methods to estimate high cycle fatigue from tensile data perform with aluminum castings, and (iv) can the axial fatigue performance of an A356-T6 casting be predicted from rotating beam fatigue data. Among the three mean stress correction models analyzed by using seven datasets from the literature, the one developed by Walker with an adjustable exponent has provided the best fit. It has been hypothesized that the adjustable Walker parameter is related to the structural quality index, QT, estimated from tensile data. Results have shown that there is indeed a strong correlation between QT and the Walker parameter. Moreover the parameters of the xvi Weibull distribution estimated from corrected data have been found to be strongly influenced by the mean stress correction method used. Tensile and fatigue life data for 319, D357 and B201 aluminum alloy castings reported in the literature have been reanalyzed by using a maximum likelihood method to estimate Basquin parameters in datasets with run-outs, Weibull statistics for censored data and mean stress correction. After converting tensile data to QT, a distinct relationship has been observed between the expected fatigue life and mean quality index for all alloys. Moreover, probability of survival in fatigue life has been found to be directly linked to the proportions of the quality index distributions in two different regions, providing further evidence about the strong relationship between elongation, i.e., structural quality, and fatigue performance [1]. Specimen geometry has been found to make the largest difference whereas the two aerospace alloys, B201 and D357, with distinctly different microstructures, have followed the same relationship, reinforcing the findings in the literature that fatigue life in aluminum castings is mainly determined by the size distribution and number density of structural defects. Six methods to predict fatigue life from tensile data have been compared by using data from the literature as well as the experimental A356 data developed in this study. Results have shown that none of the six methods provide reliable results. The consistently poor performance of the methods developed for steels and wrought alloys can be attributed to the major structural defects, namely bifilms, in aluminum castings. A new method to estimate the S-N curve from tensile data have been developed by using data for seventy-one S-N curves have been collected and Basquin parameters have been determined. Analysis showed that there is a strong relationship between QT and the Basquin exponent. xvii The Basquin parameters estimated by using the empirical relationships developed in the present study have provided better fits to the same datasets tested for the six methods. Hence the model developed in this study is proposed as the most reliable method to estimate high cycle fatigue properties. Finally, three methods to convert rotating bending fatigue test results to uniaxial fatigue data have been investigated by using the data developed in this study. Results have indicated that the method developed by Esin, in which both the fatigue life and alternating stress are corrected, provide the best estimate. Analyses of fracture surfaces of broken specimens via scanning electron microscopy have shown that tensile, axial fatigue and rotating beam fatigue properties are all strongly influenced by the same structural defects, confirming the validity of the approach taken in this study.
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