Academic literature on the topic 'QTc parameters'
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Journal articles on the topic "QTc parameters"
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Vieweg, W. Victor R. "QTc and Metabolic Parameters." Journal of Clinical Psychiatry 67, no. 05 (2006): 838. http://dx.doi.org/10.4088/jcp.v67n0521e.
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Aksoy, S. M., S. Cay, G. Cagirci, and N. Sen. "Nebivolol therapy improves QTc and QTcd parameters in heart failure patients." Cardiovascular Journal of Africa 23, no. 4 (2012): 191–93. http://dx.doi.org/10.5830/cvja-2011-046.
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Ali, ORGUN, and Demet AKBAŞ Emine. "Evaluation of Ventricular Repolarization Parameters in Obese and Extremely Obese Children." Gevher Nesibe Journal of Medical & Health Sciences 8, Özel Sayısı (2023): 701–7. https://doi.org/10.5281/zenodo.8402874.
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<strong>Aim: </strong>Ventricular arrhythmias are one of the cardiovascular disorders seen in patients with obesity. Electrocardiography (ECG) is a simple and widely used method that enables the evaluation of ventricular depolarization parameters, which are the determinants of ventricular arrhythmias. In this study, we aimed to determine the effect of obesity on ventricular repolarization parameters in children with obesity and compare children who were obese and severely obese. <strong>Material and Methods: </strong>In the study, 86 children with obesity and 84 healthy normal-weight children aged 8-18 years were evaluated. Children with obesity were divided into two groups: body mass index (BMI) <35 kg/m2 (obese) were as group 1 and ≥ 35 kg/m2 (severely obese) were as group 2. QT interval, QTc interval, QT dispersion, QTc dispersion, Tp-e interval, Tp-e / QT, and Tp -e / QTc parameters on ECG were compared between groups. <strong>Results: </strong>It was determined that the QT dispersion values of the obese group were higher than the control group; however, no significant difference was found in the parameters of QTc interval, QTc dispersion, Tp-e interval, Tp-e / QT, and Tp-e / QTc between the obese group and control group. When children with severely obesity were compared with children with obesity, no significant difference was found between the BMI groups in terms of ventricular parameters. <strong>Conclusions: </strong>In our study, we found no significant changes in ECG parameters, which are considered to be predictors of ventricular arrhythmia, except for QT dispersion in children with obesity. Similarly, found no significant difference between children with obesity and severely obesity. Therefore, ıt could be thought pathological phenomena seen on ECGs in children with obesity still need a comprehensive examination
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Genç, Ahmet, and Gülsüm Meral Yılmaz Öztekin. "Effect of sacubutril/valsartan on Tp-e, QT, QTc, Tp-e/QTc parameters in heart failure with reduced ejection fraction." Cukurova Medical Journal 49, no. 1 (2024): 47–53. http://dx.doi.org/10.17826/cumj.1377925.
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Purpose: The purpose of this study is to evaluate ventricular repolarization before, at the first month, and sixth month after Sacubutril/Valsartan, an angiotensin receptor neprilysin inhibitor (ARNI) treatment in heart failure patients with reduced ejection fraction (HFrEF).
 Materials and Methods: We included 49 patients with HFrEF who switched to ARNI therapy. The 12-lead electrocardiography (ECG) was evaluated before ARNI therapy and also during the first and sixth months of the therapy. We evaluated demographic, clinical, and laboratory parameters, as well as medications and ECG data, including heart rate. Additionally, we examined QT, QTc, Tp-e, Tp-e calculated (Tp-ec), Tp-ec/QTc, Tp-e/QT, and Tp-e/QTc.
 Results: After receiving ARNI treatment, ventricular repolarization indices were significantly reduced in the first and sixth months compared to before treatment. Specifically, the QTc values decreased from 457.6 ms to 443.8 ms, and the Tp-e/QT ratio decreased from 0.21±0.03 to 0.19±0.03. Additionally, the QTc values decreased from 457.6 ms to 444.9 ms, and the Tp-e/QT ratio decreased from 0.21±0.03 to 0.18±0.03. However, when the first and sixth months under ARNI treatment were compared, no significant difference was found (QTc: 443.8 ms vs. 444.9 ms, Tp-e/QT: 0.19±0.03 vs. 0.18±0.003).
 Conclusion: ARNI treatment in HFrEF positively affected QTc, Tp-e, and Tp-ec intervals and Tp-e/QT, Tp-e/QTc, and Tp-ec/QTc ratios, which are indicators of ventricular repolarization. Moreover, this effect started in the first month and continued in the sixth month.
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Uyar, Seyit, Mehmet Kök, Ayşe Ayan, Muhammet Ali Coşkuner, Gökhan Köker, and Nizameddin Koca. "The evaluation of the short-term and long-term hydroxychloroquine therapy on ECG parameters." Medicine 103, no. 32 (2024): e39039. http://dx.doi.org/10.1097/md.0000000000039039.
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Amidst the COVID-19 pandemic, hydroxychloroquine (HCQ) was widely administered despite limited data on its safety and efficacy. This study assesses the acute and chronic impacts of HCQ on electrocardiography (ECG) parameters alongside the effects of azithromycin and levofloxacin coadministration in patients with COVID-19. A comprehensive analysis was conducted on 109 COVID-19 patients receiving HCQ, with or without Azithromycin and/or Levofloxacin, and 51 long-term HCQ-treated Sjogren’s syndrome (SS) patients. ECG parameters, including QTc interval, were meticulously evaluated against a control group of 109 COVID-19 patients without HCQ treatment. HCQ monotherapy, in combination with Levofloxacin, significantly prolonged the QTc interval in COVID-19 patients compared to controls. Notably, the combination of HCQ and Azithromycin demonstrated a mitigated impact on QTc prolongation. Long-term HCQ use in SS patients did not significantly affect QTc intervals, illustrating a distinct safety profile from short-term use in COVID-19 treatment. HCQ’s impact on QTc prolongation is influenced by therapeutic context, coadministered drugs, and patient demographics. The findings underscore the necessity of cautious HCQ use, particularly in acute settings like COVID-19, where monitoring and consideration of drug interactions and patient-specific factors are critical.
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Hocagil, Hilal, Abdullah Cüneyt Hocagil, and Tuğba Akkaya Hocagil. "Evaluation of the Risk of Malignant Arrhythmia Through Electrocardiography Parameters in Patients with Urinary Stone Disease." Medical Journal of Western Black Sea 8, no. 2 (2024): 129–34. http://dx.doi.org/10.29058/mjwbs.1397031.
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Introduction: With a lifetime frequency of 10-15% and a recurrence rate of up to 50% within 10 years, urinary stone disease is a major cause of comorbidity. Recently, it has become widely recognized that urinary system stone disease is not only limited to kidney stone development but is also linked to cardiovascular disease and various other illnesses. Malignant arrhythmias (sudden cardiac death and ventricular arrhythmias) are consequences of coronary artery disease. Despite numerous studies demonstrating that urinary system stone disease is a risk factor for coronary artery disease, no electrocardiographic parameters have been evaluated in this patient group This prospective observational study aims to assess ventricular repolarization parameters using electrocardiography, which are risk indicators for malignant arrhythmias in patients with urinary stones disease. Materials and Methods The study included patients diagnosed with urinary stone disease and healthy volunteers. All patients underwent 12-lead electrocardiography. The electrocardiographys were evaluated for QTc interval, QTc dispersion, T peak-end interval, and Tp-e/QTc, and compared with the control group. Results: When comparing the QTc interval, QTc dispersion, T peak-end interval, and Tp-e/QTc parameters between the patient and control groups, no statistically significant differences were found. Conclusion: Contrary to existing knowledge, this study found that malignant arrhythmias in patients with urinary stone disease were not significantly different from the normal population.
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MUHAMMED MUSHTAQ AHMED, ASHOK P YENKANCHI, HABIBULLAH ATTAR, SAIFUDDIN SARGIRO, and SHARHAN PP. "A study on QT dispersion and thrombolytic therapy in acute myocardial infarction." International Journal of Science and Research Archive 13, no. 1 (2024): 2489–795. http://dx.doi.org/10.30574/ijsra.2024.13.1.1968.
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Background: Myocardial infarction is a major manifestation of ischemic heart disease, a leading cause of death in developed nations and the third globally. QTc dispersion is an important marker of ventricular repolarization variations and arrhythmogenic risk. This study examines the effects of thrombolytic therapy on QTc dispersion in acute myocardial infarction Materials and methods: 88 patients admitted to Al Ameen Medical College Hospital, Vijayapur, for acute MI were included in the study. Over a period of 8±2 days, all patients underwent monitoring, with standard 12-lead ECGs conducted upon admission and before discharge. QT interval, QTc interval, and QT and QTc dispersion parameters were calculated from these ECGs. Results: Analysis revealed significant variations in QT parameters between patients treated and not treated with thrombolytic therapy. Patients receiving thrombolytic therapy exhibited greater reductions in QT parameters by day 8±2 compared to those without treatment. Additionally, anterior wall infarctions demonstrated significantly higher QT and QTc dispersions compared to inferior wall infarctions, with these differences being statistically significant. Conclusion: In the early stages of acute myocardial infarction, patients, especially those diagnosed with anterior myocardial infarction, exhibited significantly elevated QT and QTc dispersions. Thrombolytic treatment resulted in substantial reductions in these dispersions compared to untreated individuals. Typically peaking within the initial hours of the condition, these dispersions subsequently decline following successful thrombolysis, underscoring their significance in risk assessment for malignant ventricular tachyarrhythmias and reinforcing the efficacy of thrombolytic therapy
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МУРОМЦЕВА, Г. А., and В. В. КОНСТАНТИНОВ. "Prognostic parameters of the electrocardiogram and electrical heterogeneity of the ventricular myocardium." Kardiologicheskii vestnik, no. 3() (August 24, 2020): 54–59. http://dx.doi.org/10.36396/ms.2020.16.3.007.
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Основываясь на механизмах электрической гетерогенности миокарда желудочков, рассмотрены наиболее вероятные показатели ЭКГ, отраG жающие этот процесс. К их числу относят длительности комплекса QRS, электрической систолы (интервал QT и его корригированные формы, QTc и QTa) интервалы конечной части желудочкового комплекса (QTpa, TpTe), а также угловые характеристики периода реполяризации (углы TpGTref, TinitGTterm) и, главное, желудочковый градиент, пространственный и фронтальный углы QRSGT. В клинических и эпидемиологических исследованиях показаны высокие прогностические возможности этих показателей по выявлению фатальных и нефатальных сердечноGсосуG дистых событий и внезапной сердечной смерти. Обзор нацелен на активизацию интереса врачей, исследователей и разработчиков программ компьютерного анализа ЭКГ к прогностически значимым показателям, которые последние десятилетия широко обсуждаются в зарубежной литературе, но не используются отечественными специалистами. Ключевые слова: прогностические показатели ЭКГ, электрическая гетерогенность миокарда, желудочковый градиент, угол QRSGT. Summary The most likely ECG indicators predicting of electrical heterogeneity of the ventricular myocardium are considered. These include the durations of the QRS complex, the electrical systole (QT interval and its corrected forms, QTc and QTa), the intervals of the final part of the ventricular complex (QTpa, TpTe), as well as the angular characteristics of the repolarization period (TpGTref, TinitGTterm angles), the ventricular gradient, spatial and frontal angles of QRSGT. Clinical and epidemiological studies have shown high predictive capabilities of these indicators for detecting fatal and nonGfatal cardiovascular events and sudden cardiac death. The review is aimed for activation of the interest of doctors, researchers and developers of computer ECG analysis programs to these prognostic indicators, which have been widely discussed in foreign literature for the past decades, but most of them not use in national routine medical practice yet.
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Wilk-Śledziewska, Katarzyna, Rafał Śledziewski, Małgorzata Gryciuk, et al. "Heart Failure, Kidney Function, and Elderly Age, Rather than Levofloxacin Therapy, Are Associated with QTc Prolongation in COVID-19 Patients." Journal of Clinical Medicine 14, no. 11 (2025): 4006. https://doi.org/10.3390/jcm14114006.
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Background: Prolongation of the QT interval is directly related to the risk of ventricular arrhythmias and sudden cardiac death. Age, comorbidities, and treatment schemes have been shown to influence its prolongation and may also significantly affect the course of SARS-CoV-2 infection. Fluoroquinolones, widely used during the COVID-19 pandemic, are known for their ability to prolong the QT interval. Risk of ventricular arrhythmias has also been reported in patients with infectious diseases, and this risk may have been associated with high levels of interleukin-6 (IL-6). Purpose: The aim of this study is to evaluate the effect of levofloxacin on the corrected QT interval in patients with COVID-19, as well as to identify sociodemographic, clinical, and biochemical parameters associated with QTc interval prolongation among patients with COVID-19. Patients and Methods: The medical records of 93 patients hospitalized for COVID-19 were retrospectively analyzed, focusing on the presence of comorbidities and treatment with levofloxacin. Selected sociodemographic, clinical, and biochemical parameters were then statistically analyzed, with emphasis on their effect on the corrected QTc interval. The QTc interval was calculated according to the Bazett formula. Results: Levofloxacin use was not significantly associated with QTc interval. Statistical analysis identified creatinine, heart failure and atrial fibrillation as significant predictors of QTc interval prolongation. The trends towards QTc interval prolongation observed with hypokalaemia and hypertension suggest that these factors may also contribute to QTc interval variability and should be taken into account when assessing arrhythmia risk. Conclusions: Our retrospective study indicates that QTc prolongation results from the interplay of multiple factors.
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Geçkalan, Damla, Rahmi Özdemir, Yasin Yılmaz, Cemile Hilal Çelik, Batuhan Berk Demir, and Yeşim Tunç. "Can hydroxychloroquine and azithromycin combination cause cardiac rhythm disturbances in children with COVID-19 pneumonia?" Journal of Health Sciences and Medicine 8, no. 2 (2025): 308–12. https://doi.org/10.32322/jhsm.1625339.
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Aims: At the beginning of the COVID-19 pandemic; it has been shown that receiving hydroxychloroquine and azithromycin treatment decrease viral carriage of coronavirus in patients. In this study, we aimed to evaluate electrocardiography (ECG) abnormalities in pediatric patients with COVID-19 pneumonia receiving combined therapy with hydroxychloroquine and azithromycin. Methods: In this study; ECG and laboratory parameters of 24 children with COVID-19 pneumonia who were treated with hydroxychloroquine and azithromycin at Health Sciences University between June 2020 and November 2020 were analyzed retrospectively. P wave dispersion (PWd), QT interval (QT), QT dispersion (QTd), QTc interval (QTc), QTc dispersion (QTcd), Tpeak-Tend interval (Tp-e), Tp-e dispersion (Tp-ed), Tp-e/QT, Tp-Te/QTc ratios were evaluated with 12 lead ECG. ECG parameters and QTc interval were compared before and after (5 days) the treatment. Results: The mean age was 13±4.5 years and 62.5% were female. Median hospitalization length was 6 days. There was no statistically significant difference between the PWd, QT and QTc interval, QTd, QTcd, Tp-e interval, Tp-e dispersion, Tp-e/QT, Tp-e/QTd measurements and ratios of the before and after treatment. A significant difference was found for the decrease in hearth rate in regard to the measurement before and after the treatment. Conclusion: In our study, there were no rhythm problems which were observed on ECG in pediatric patients receiving hydroxychloroquine and azithromycin combination therapy for COVID-19 pneumonia. We also found that laboratory parameters were not specific for COVID-19 pneumonia in children.
Dissertations / Theses on the topic "QTc parameters"
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Longa-Peña, Penélope Alejandra. "Orbital parameters estimation for compact binary stars." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/75554/.
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Most stars in the Galaxy are found in multiple systems of two or more stars orbiting together. Two stars orbiting around their centre of mass are called binary stars. In close binary stars, the evolution of one star affects its companion and evolutionary expansion of one star allows for mass exchange between the components. In most cases, the material from the less massive star forms an accretion disc around the heavier companion that has evolved into a compact stellar remnant, the final state of stellar evolution. We call these systems compact binary stars (CBs). The study of CBs is key to the development of two fundamental phenomena: accretion and evolution of binary stars. Statistical information on CBs can be deduced by extracting common properties and characteristic system parameter distributions from observed data. But, despite being fundamental for a wide range of astronomical phenomena, our comprehension of their formation and evolution is still poor, mainly because of the limited knowledge of crucial orbital parameters. This lack of reliable orbital parameters estimation is mainly due to observational handicaps, namely, the accretion disc outshines the system components. Astronomers have developed different techniques to overcome this, but are often very dependant of the signal to noise ratio of the data or are only able to obtain via target of opportunity programs (wait until the target is brighter). The focus of this work is to test and develop techniques, based on indirect imaging methods, that can overcome the main observational handicaps to estimate orbital parameters of CBs. We combine these techniques with the exploitation of more “exotic” emission lines that trace the irradiated face of the donor star, namely Ca II NIR triplet and the Bowen blend. We made use of empirical properties of Doppler tomography to estimate the values of the phase zero Á0 and the velocity of the irradiated face of the secondary star (Kem). We then used synthetic models accounting for an irradiated secondary to fit our measured Kem and perform a K-correction to derive the radial velocity of the secondary K2. To derive K1, we used the centre of symmetry technique, testing its validity among several emission lines and the stability of the results depending on the selected area. Having strong constraints for K1 and K2, we find estimates for the mass ratio q. Furthermore, we developed a variation from the Doppler tomography secondary emission method to constrain the value of the systemic velocity ƴ. We derive meaningful uncertainties of these parameters with the bootstrap technique. Using these techniques, we have successfully set dynamical constraints on the radial velocities of the binary components of CBs and derived fundamental orbital parameters, including the mass ratio, using basic properties of Doppler tomography.
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Islam, Salma. "Exploring the parameters of peculiar velocity fields." Thesis, University of Glasgow, 2019. http://theses.gla.ac.uk/41045/.
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The main focus of this work is to make use of a novel tool in the cosmologist's toolbox when it comes to constraining the parameters of the peculiar velocity fields of the nearby Universe called ROBUST, whose unique properties and lack of reliance on secondary distance indicators sets it apart from other available constraining techniques, rendering it potentially very useful for future upcoming surveys such as the LSST and the SKA. While ROBUST proves itself more than adequate in constraining parameters in a mock controlled environment with the IRAS PSCz survey, it begins to struggle when applied to the real-world 2MRS survey, primarily due to an inherent fault in the survey that causes it to not function properly with the program. These problems persist even when we begin to make use of one of the ancillary tools developed in conjunction with ROBUST, namely relative entropy, despite it once again continuing to function adequately across multiple mock realisations. It is the conclusion of this work that while ROBUST is not successful in recovering values for the cosmological parameters we seek to constrain, this does not necessarily negate its viability for use with upcoming surveys, as it has proven itself successful in determining exclusion intervals on the value of the linear redshift distortion parameter β for real world surveys that are in very good agreement with the generally small values computed by contemporary velocity-velocity constraining techniques such as VELMOD and χ2 minimisation, while also confidently ruling out the results of older density-density constraining techniques such as POTENT that favour values closer to unity.
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Marzola, Luca. "On leptogenesis, flavour effects and the low energy neutrino parameters." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/346819/.
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Contemporary physics is testing the boundaries of one of its existent paradigms, the Standard Model of Particle Physics. In recent years many attempts have been made in order to overcome the difficulties arising within this well known framework. Along with the effort made on the experimental side, for example the search for the Higgs boson at the Large Hadron Collider, there is a present requirement for testable theoretical scenarios describing physics beyond the current paradigms. To this purpose we consider the type I Seesaw extension of the Standard Model, in which the neutrino mass puzzle is possibly solved and the baryon asymmetry of the Universe explained via Leptogenesis. After reviewing the basis of the Seesaw mechanism and its recent developments we present a rigorous investigation which confirms the validity of the adopted description. Encouraged by this success we then employ the interplay of light and heavy neutrino flavour e↵ects to address the problem of initial conditions in Leptogenesis. Our analysis identifies the ⌧ N2-dominated scenario as the only possible answer, proposing a well defined setup in which successful strong thermal Leptogenesis is achieved. Attracted by the properties of our solution we consequently investigate its compatibility with the SO(10)-inspired model of Leptogenesis. The result is indeed intriguing: the strong thermal solutions of the SO(10)-inspired model deliver sharp predictions on the lowenergy neutrino parameters that fall within the reach of future neutrino experiments,opening up the possibility of a full test of this attractive Leptogenesis scenario.
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Chung, A. L. "Material parameter extraction in terahertz time domain spectroscopy." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/352056/.
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In terahertz time domain spectroscopy (THz-TDS) material parameter extraction is necessary for determining the complex refractive index of materials in the THz region. The process of material parameter extraction requires the fitting of a theoretical model for the propagation the THz pulse through the material to experimentally acquired THz time domain data, where by the complex refractive index of the theoretical model is varied until it fits the experimental data. It requires close agreement between a model of the THz electric field propagation and experimental THz data for accurate extraction of the complex refractive index. In this thesis I report on the methods of material parameter extraction with the goal of accurately determining the complex refractive index of materials within the THz region. I also investigate a series of optimisation techniques from understanding the behaviour of the extracted complex refractive index for different model assumptions and initial parameters. The inclusion of the material parameter extraction optimisation techniques allows for material parameter extraction methods which are similar to the state of the art in the field. Material placed at the THz focus are commonly investigated using the plane wave assumption for material parameter extraction. I demonstrate an extraction method which models a converging beam, this improves the accuracy of the extracted complex refractive indices for materials placed in focused THz-time domain spectrometers. Furthermore, I have developed an elegant method to determine the angular beam profile of the focussed THz beam by using the converging beam extraction method. Finally I report on the THz-TDS performance of photoconductive THz generation and detection from a high peak power vertical external cavity surface emitting laser (VECSEL). VECSELs are optically pumped semiconductor disk lasers (SDL) which are inherently compact, have multi-GHz repetition rates and could lead to a cost effective THz spectrometer system.
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Day, Stephen Paul. "Approaches to ab-initio GIPAW-DFT calculations of NMR parameters in disordered materials." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/78781/.
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The use of ab initio Density Functional Theory (DFT) to calculate key Nuclear Magnetic Resonance (NMR) parameters has been shown to be very successful in a variety of cases. These calculations allow one to extract meaningful data from NMR measurements by providing a foundation for spectral peak assignment. However, first principle calculations for disordered systems, typically based on a single realisation of the disorder, are inadequate if the NMR parameters depend sensitively on the location of the disordered species. In this thesis, a number of different approaches for characterising disorder in solids are presented. The aim of which is to overcome current challenges regarding the computational cost of conventional supercell approaches that make it difficult to perform a direct study of the complete configurational ensemble for any supercell with a sufficient simulation cell. A case study is presented for the Ge-based apatite La7.5Ca2.5Ge6O25.75 that shows that the number of configurations one needs to consider can be vastly reduced by exploiting the symmetry of the system over a wholly enumerative approach, although exhaustive statistical averaging of the atomic positions required to reproduce the atomic resolution afforded by the solid-state NMR (ssNMR) measurement makes this problem intractable via this methodology. The sodium potassium niobate system (NaxK1-xNbO3) is studied across a series of compositions between the ordered KNbO3 and NaNbO3 end-members. This novel material exhibits purely atomic position / permutation disorder that is reflected in initial 23Na and 93Nb MAS NMR studies, but the true explanation of the disorder described by this data is not well understood. The Special Quasi-random Structure (SQS) approach to studying this disorder is presented as a computationally cheaper alternative to the supercell approach. It is noted that further studies are required to assess whether this is an adequate description of the NaxK1-xNbO3 system due the complications of modelling the complex tilting patterns exhibited by these structures. A combined ssNMR and GIPAW-DFT approach is reported to resolve the complex disorder within the vaterite polymorph of calcium carbonate. The computational data for the various structural candidates in the literature is utilised to simulate the highly sensitive DOR data, thereby elevating the predictive capability of this complementary approach to substantiate the stacking model of vaterite that views the material as a dynamic system under ambient conditions.
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Pilar, T. "Measurement of the neutral D meson mixing parameters in D0 -> KSπ+π− decays". Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/66723/.
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A model-independent measurement of the charm mixing parameters xD and yD in the D0 -> KSπ+π− decay mode is presented. The method uses ratios of yields in symmetric bins of the Dalitz plot and is binned in decay time. This is an alternative approach that does not require the knowledge of the phase-space model of the decay. It also preserves good sensitivity to xD and to the relative sign between xD and yD. Charm mixing parameters are an important step to measuring CP violation in charm mixing. The measured values of the mixing parameters are xD = (1.89±0.43±0.21±0.51)% and yD = (−2.59±1.36±1.13±3.12)% where the uncertainties are statistical, systematic, and due to input parameters respectively.
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Dagtekin, Ebru. "Measurement Of Nonuniform Magnetized Argon Plasma Discharge Parameters." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607934/index.pdf.
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Effects of a magnetic field on the double-probe technique are studied experimentally by means of symmetric floating computer controlled fast double probes in low and intermediate pressure plasmas. In addition, the effects of the magnetic field on the electron temperature, electron density, and electric field have been investigated. As it is expected, when there is no magnetic field, properties of the discharge plasma are best described by Langmuir theory. Whereas, when there&rsquo<br>s a magnetic field of sufficient strength Schottky&rsquo<br>s theory of ambipolar diffusion applies.
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Yan, Bo. "Active vibration isolation with a distributed parameter isolator." Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/51281/.
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Conventional vibration isolators are usually assumed to be massless for the purpose of modelling. This simplification tends to overestimate the isolator performance because of neglecting the internal resonances (IRs) due to the distributed mass effects in the isolator, which is especially important for lightly damped metallic isolators. Previous research on the problem of IRs is not particularly comprehensive, because it does not clarify the characteristics of the distributed parameter isolator. Furthermore, with the development of active vibration isolation, there is a need to investigate the effects of isolator IRs on the control performance and stability for commonly used control strategies. Effective ways to attenuate these effects are also required. This thesis concerns the active vibration isolation of a piece of delicate equipment mounted on a distributed parameter isolator, which is modelled as different idealised configurations under various types of deformation. The model is first developed to determine the effects of IRs on a single-degree-of-freedom system with a distributed parameter isolator. This analysis is then extended to include the resonance behaviour of the supporting structure. Simple expressions are derived which describe the behaviour of various types of distributed parameter isolator. The parameters which control the isolator performance at various frequencies are clarified theoretically and experimentally. The effects of IRs on control performance and stability of several control strategies are determined and compared. Absolute Velocity Feedback (AVF) control is shown to be the optimal solution to minimise the mean square velocity of the equipment mass supported by a distributed parameter isolator. A stability condition for an AVF control system containing a distributed parameter isolator is proposed. Based on this condition, different approaches to stabilize such a control system are presented. Experimental work is carried out to validate the theoretical results. Based on the improved knowledge of the characteristics of IRs in the distributed parameter isolator, different approaches which can suppress the IRs are proposed. AVF control with more damping in the isolator is demonstrated to be effective in attenuating the IRs theoretically and experimentally. Absolute velocity plus acceleration feedback control and AVF control on a fraction of the isolator length are also shown theoretically to be effective ways to attenuate the IRs and improve the isolation performance over a broad range of frequencies.
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Berger, Iris. "Assoziation des QTc-Intervalls und anderer EKG-Parameter mit Polymorphismen im Ankyrin-B-Gen in der MONICA-Augsburg-Population verglichen mit Polymorphismen im Ankyrin-B-Gen in einem Hochrisikokollektiv." kostenfrei, 2008. http://www.opus-bayern.de/uni-regensburg/volltexte/2008/1048/.
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Haster, Carl-Johan Olof. "Compact, diverse and efficient : globular cluster binaries and gravitational wave parameter estimation challenges." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6839/.
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Following the first detection of gravitational waves from a binary coalescence, the study of the formation and evolution of these gravitational-wave sources and the recovery and analysis of any detected event will be crucial for the newly realised field of observational gravitational wave astrophysics. This thesis covers a wide range of these topics including simulating the dense environments where compact binaries are likely to form, focusing on binaries containing an intermediate mass black hole (IMBH). It is shown that such binaries do form, are able to merge within a ∼ 100 Myr simulation, and that the careful treatment of the orbital evolution (including post-Newtonian effects) implemented here was crucial for correctly describing the binary evolution. The later part of the thesis covers the analysis of the gravitational waves emitted by such a binary, and shows it is possible to identify the IMBH with high confidence, together with most other parameters of the binary, despite the short-duration signals and assumed uncertainties in the available waveform models. Finally a method for rapid parameter estimation of gravitational wave sources is presented and shown to recover source parameters with comparable accuracy using only a small fraction ∼ 0.1% of the computational resources required by conventional methods.
Books on the topic "QTc parameters"
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Agbenu, Sabine. Die QT-Dispersion und weitere Dispersionsparameter des EKGs als prognostische Parameter für Myokardinfarktpatienten. 1998.
Find full textBook chapters on the topic "QTc parameters"
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Zanetti, S., M. Keller, M. Winzeler, W. Saurer, B. Keller, and M. Messmer. "QTL for quality parameters for bread-making in a segregating wheat by spelt population." In Developments in Plant Breeding. Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4475-9_40.
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Galimberti, Andrea. "FPGA-Based Design and Implementation of a Code-Based Post-quantum KEM." In Special Topics in Information Technology. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-51500-2_3.
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AbstractPost-quantum cryptography aims to design cryptosystems that can be deployed on traditional computers and resist attacks from quantum computers, which are widely expected to break the currently deployed public-key cryptography solutions in the upcoming decades. Providing effective hardware support is crucial to ensuring a wide adoption of post-quantum cryptography solutions, and it is one of the requirements set by the USA’s National Institute of Standards and Technology within its ongoing standardization process. This research delivers a configurable FPGA-based hardware architecture to support BIKE, a post-quantum QC-MDPC code-based key encapsulation mechanism. The proposed architecture is configurable through a set of architectural and code parameters, which make it efficient, providing good performance while using the resources available on FPGAs effectively, flexible, allowing to support different large QC-MDPC codes defined by the designers of the cryptosystem, and scalable, targeting the whole Xilinx Artix-7 FPGA family. Two separate modules target the cryptographic functionality of the client and server nodes of the quantum-resistant key exchange, respectively, and a complexity-based heuristic that leverages the knowledge of the time and space complexity of the configurable hardware components steers the design space exploration to identify their best parameterization. The proposed architecture outperforms the state-of-the-art reference software that exploits the Intel AVX2 extension and runs on a desktop-class CPU by 1.77 and 1.98 times, respectively, for AES-128- and AES-192-equivalent security instances of BIKE, and it provides a speedup of more than six times compared to the fastest reference state-of-the-art hardware architecture, which targets the same FPGA family.
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Najeeb, Sofi, Anumalla Mahender, Annamalai Anandan, Waseem Hussain, Zhikang Li, and Jauhar Ali. "Genetics and Breeding of Low-Temperature Stress Tolerance in Rice." In Rice Improvement. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66530-2_8.
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AbstractLow-temperature stress (LTS) is one of the major abiotic stresses that affect crop growth and ultimately decrease grain yield. The development of rice varieties with low-temperature stress tolerance has been a severe challenge for rice breeders for a long time. The lack of consistency of the quantitative trait loci (QTLs) governing LTS tolerance for any given growth stage over different genetic backgrounds of mapping populations under different low-temperature stress conditions remains a crucial barrier for adopting marker-assisted selection (MAS). In this review, we discuss the ideal location and phenotyping for agromorphological and physiological parameters as indicators for LTS tolerance and also the traits associated with QTLs that were identified from biparental mapping populations and diverse rice accessions. We highlight the progress made in the fields of genome editing, genetic transformation, transcriptomics, and metabolomics to elucidate the molecular mechanisms of cold tolerance in rice. The stage-specific QTLs and candidate genes for LTS tolerance brought out valuable information toward identifying and improving LTS tolerance in rice varieties. We showed 578 QTLs and 38 functionally characterized genes involved in LTS tolerance. Among these, 29 QTLs were found to be colocalized at different growth stages of rice. The combination of stage-specific QTLs and genes from biparental mapping populations and genome-wide association studies provide potential information for developing LTS-tolerant rice varieties. The identified colocalized stage-specific LTS-tolerance QTLs will be useful for MAS and QTL pyramiding and for accelerating mapping and cloning of the possible candidate genes, revealing the underlying LTS-tolerance mechanisms in rice.
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Svorc Jr, Pavol, and Pavol Svorc. "Rat Electrocardiography and General Anesthesia." In Cardiovascular Diseases [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.104928.
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General anesthesia is an established and well-known factor with a significant impact on cardiac parameters, which can be a problem in the final evaluation of changes in the individual electrophysiological myocardial parameters after various interventions. The present chapter provides a composite review of published data on electrocardiographic parameters (heart rate, PR interval, P wave duration, P wave amplitude, QRS complex, QT and QTc interval duration, and R wave and T wave amplitude) for in vivo rat experiments under general anesthesia from 130 articles, which were retrieved from a search of the Web of Science database, for articles published mainly between 2000 and 2021. ECG parameters reported as baseline or control values were summarized, and averages with ranges were calculated. It is important to be cautious in interpreting the results of such studies and discussions addressing the mechanisms underlying a given type of arrhythmia, it is important to acknowledge that initial ECG parameters may already be affected to some extent by general anesthesia as well as by sex and the time of day the experiments are performed. Although it is not an original research work, researchers working with rats in the laboratory, who routinely perform anesthesia, can use this as a reference to look into while analyzing their data.
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Lin, X., H. Zhang, and A. M. Rappe. "Optimization of quantum Monte Carlo wave functions using analytical energy derivatives." In Quantum Monte Carlo. Oxford University PressNew York, NY, 2007. http://dx.doi.org/10.1093/oso/9780195310108.003.00125.
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Abstract The optimization of parameters in trial wavefunctions by minimizing the variance in local energy was used for some of the earliest variationala and diffusionb QMC calculations, and it has been used ever since by most practitioners of QMC. Perhaps the best known examples are given in the paper by Schmidt and Moskowitzc for optimizing their nine-parameter Jastrow functions for first-row atoms. An alternative method of optimization, leading to lower variational energies for these atoms, is reported in this paper.
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Das, Sudeshna, Anshit Mukherjee, and Sohini Banerjee. "Quantum-Driven Hydrology." In Advances in Computational Intelligence and Robotics. IGI Global, 2025. https://doi.org/10.4018/979-8-3693-9770-1.ch017.
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Flood has emerged as a pressing global problem with climate change impact that endangers our security, structures, and balance of nature. The conventional flood forecast techniques therefore face challenges with available data and with computation computations. We proposed a new Quantum Variational Hydrological Paradigm, based on Quantum-Train Long Short-Term Memory (QT-LSTM) model, that optimises parameter training with a significant decrease of trainable parameters compared with traditional models to predict flood and disaster management. The model takes a centralized dataset consisting of historical flood data, and meteorological information. We also incorporated a quantum game theoretical decision aiding mechanism to enhance the decision making on flood management measures. Outcome shows that the utilization of QT-LSTM model highly enhances the accuracy and efficiency of the forecasted values by generating lower RMSE than the conventional techniques.
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Kapoor, Nishant Raj, Ashok Kumar, Anuj Kumar, Aman Kumar, Harish Chandra Arora, and Hashem Jahangir. "Quantum Computing for Indoor Environmental Quality." In Advances in Systems Analysis, Software Engineering, and High Performance Computing. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-6697-1.ch011.
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Quantum computing (QC) is founded on the principles of quantum entanglement and the superposition of matter. It employs advanced computation techniques rather than conventional ones. To circumvent the limitations of conventional computing, new supercomputers employ quantum mechanics knowledge, which allows for the coherence of ones and zeros. Several fields like finance, healthcare, cybersecurity, transportation, climate change, and many more are taking advantage of QC. Indoor environmental quality (IEQ) is also one of the sectors that can benefit enormously with QC. The IEQ contains several parameters. Major IEQ parameters are indoor air quality, thermal comfort, acoustic comfort, and visual comfort. These parameters are associated with several physical, chemical, and biological components, which need critical computational considerations for accurate results and better understanding as the data can be highly overlapped. This chapter contains possible forthcoming research opportunities available in the collaborative work between “indoor environment” and “quantum computing.”
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Lu, S. I. "The accuracy of diffusion quantum l\fonte Carlo simulations in the determination of molecular equilibrium structures." In Quantum Monte Carlo. Oxford University PressNew York, NY, 2007. http://dx.doi.org/10.1093/oso/9780195310108.003.00154.
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Abstract Results of fixed-node diffusion QMC calculations for 17 small molecules made up of atoms H, C, N, 0, and F were compared in this paper to experimental values for atomization energies, bond lengths, and bond angles, as well as corresponding values from coupled cluster calculations. The QMC calculations were of the Ornstein-Uhlenbeck type,a with trial functions for importance sampling and node locations based on linear combinations of determinants with molecular orbitals composed of floating spherical Gaussian orbitals. Initial geometries were taken from density functional calculations and optimized to find the minima given by the QMC calculations. Zero-point energies were calculated using the energy gradients given by the same calculations. The calculated atomization energies for the 14 species for which experimental data were available were in excellent agreement with the experimental values and with values given by CCSD(T) with a cc-pVQZ basis set. The mean absolute deviation from experimental atomization energies was 0.16 kcal/mol for the QMC and 0.21 kcal/mol for the CCSD(T) calculations. Geometric parameters were in agreement with each other and with experimental values within their uncertainties. Overall, the results provide a solid confirmation of the accuracy of fixed-node diffusion QMC calculations.
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Nekovee,, M., W. M. C. Foulkes, and R. J. Needs. "Quantum Monte Carlo studies of density functional theory." In Quantum Monte Carlo. Oxford University PressNew York, NY, 2007. http://dx.doi.org/10.1093/oso/9780195310108.003.00145.
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Abstract It is difficult to imagine that density functional theory (DFT) could be useful in improving quantum Monte Carlo methods, but it is easy to imagine that QMC could be useful in improving density functional methods. Since QMC can produce accurate wavefunctions and since wavefunctions lead to all other properties one should be able, in principle, to use QMC to predict the exchangecorrelation energy functional Exc[n(r)], the key (unknown) quantity required in DFT. In practice, that is not so easy, but this paper shows how QMC can take steps in that direction by providing insights gained from comparisons of results from QMC and DFT. The authors considered the case of the strongly inhomogeneous electron gas using variational Q:tvIC to obtain wavefunctions 1/J&gt;. and energies E[7/J&gt;.] for the ground state of the Hamiltonian iI&gt;- = T +AVee+V &gt;. associated with the coupling constant A in the range 0 to 1. Optimization of a Slater-Jastrow many-body wavefunction was made by minimizing a penalty function given by a weighted sum of the variance in local energies and a sum of squares of electron density differences. The variational parameters in 7/J&gt;. and v&gt;. were repeatedly varied to reach convergence followed by additional calculations to obtain the local values of the exchange-correlation energies e c and the exchange-correlation holes n c from which Exe and nxc could be determined.
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Mcmillan, W. L. "Ground state of liquid 4He." In Quantum Monte Carlo. Oxford University PressNew York, NY, 2007. http://dx.doi.org/10.1093/oso/9780195310108.003.0005.
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Abstract One of the earliest uses of Metropolis samplinga in variational QMC calculations was not in an electronic structure problem, but in the calculation of the energy of a sample of liquid helium in which the atoms were treated as single particles. The interaction among the atoms was specified as a pairwise-additive Lennard-Jones 6-12 potential, which is a rather good approximation in this case. The trial wavefunction was a product form of the type Πi&lt;j f(rij ), with f(r) = exp [-(a1/r)a 2] and variable parameters a1 and a2 . The ground-state wavefunction for this collection of bosons is nodeless. Calculations were carried out with 32 to 108 atoms at several lattice densities in a cube with periodic boundary conditions. The energies so determined were within about 20% of the experimental values and two-body correlation functions were in reasonable agreement with those derived from x-ray data. This first variational QMC calculation for liquid helium was followed within a few years by both Green’s function and diffusion QMC calculations.
Conference papers on the topic "QTc parameters"
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Weintritt, Donald J. "QA/QC Parameters for Produced Waste Water - Operations versus Regulatory Compliance." In CORROSION 1993. NACE International, 1993. https://doi.org/10.5006/c1993-93162.
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Abstract The level of QC for sampling and testing produced waste water for operations has several levels: monitoring, special tests, litigation and regulatory requirements. Points to consider in setting requirements for each of these situations are discussed. Because of the non-uniform nature of oilfield waste waters, special attention is focused on sampling in the field and again in the laboratory as the major source of total variance regardless of the end use of the data.
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Ghasemi, Mehrdad, Hassan Kaatuzian, Houshyar Noshad, and Mahdi NoroozOliaei. "Quantum Photonic Computer Challenges: Quantum Decoherence, Quantum Error Correction (QEC), and Scalability." In Frontiers in Optics. Optica Publishing Group, 2024. https://doi.org/10.1364/fio.2024.jd4a.42.
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The error correction process in quantum photonic computers (QPCs) and their loss in photons are two important parameters of considering them as reliable devices for computing very large and complicated problems concerning classical computers. In this paper, the new promising algorithms have been discussed for employment in quantum photonic computers as robust and reliable computational tasks to define the best fidelity as a figure of merit in quantum error correction schemes. Furthermore, a parametric study has been done by adding noble metals to the Integrated Photonic Chip.
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Murray, John N. "A Re-investigation of the Testing Parameters for Evaluating the Initial Electrochemical Characteristics of Indium Activated, Aluminum Alloy, Sacrificial Anodes." In CORROSION 2004. NACE International, 2004. https://doi.org/10.5006/c2004-04098.
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Abstract There are a variety of electrochemical (EC) tests that have been published for characterizing aluminum alloy materials for sacrificial anode applications. This paper expands on a previously disclosed 20 hour QA/QC test method. New data are presented regarding the effects of type, concentration and pH of the test electrolyte, the extent of the influence of the freshly formed oxide film as well as the surface roughness on the EC test results. Evidence of the mal-distribution of the alloy chemistry is also presented and discussed.
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Ebrahimi, Nafiseh, Jieying Zhang, Istemi Ozkan, and Hamidreza Shirkhani. "Effect of Environmental Parameters on Atmospheric Corrosion of Carbon Steel Infrastructures in Montreal, Qc, Canada: past, Current and Future Scenarios." In CONFERENCE 2022. AMPP, 2022. https://doi.org/10.5006/c2022-17819.
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Abstract Atmospheric corrosion plays a critical role in structural metal loss and thus infrastructure service life. Since the 1920's, many studies have focused on the effect of environmental parameters on the corrosion of major construction metals and it has been shown that chlorides, pollutants in the air such as sulfur dioxide, temperature, and relative humidity are the main environmental factors affecting the corrosion rate. Several studies have come up with a dose response function to predict the corrosion rate of a specific metal based on the environmental factors it is exposed to. The predicted corrosion rate is a critical design factor to secure safe and reliable infrastructure performance during its design service life. Therefore, future climatic changes in the environment may need to be considered when selecting a proper material and its required thickness as changes in environmental factors due to climate change in certain regions may affect the corrosion rates. Currently, historical data is used for designing infrastructures without considering the future climatic changes. This study summarizes the effort on atmospheric corrosion programs involving Canada's climate and illustrates the changes in corrosion rate of carbon steel in the City of Montreal over the past 70 years and up to 80 years in the future using the projections of climatic models. The goal is to demonstrate the effect of climate change and the variation in atmospheric exposure conditions for future durability designs of infrastructures such as bridges against atmospheric corrosion.
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Partridge, Paul. "Multi-Layer Pipeline Coating Systems: a New Look at the Evaluation of Certain QC Tests and Critical Application Parameters for FBE Primers." In CORROSION 2006. NACE International, 2006. https://doi.org/10.5006/c2006-06053.
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Abstract Advancing technologies for pipeline construction techniques and increasingly severe operating parameters present challenges for pipeline coatings. Multi-layer coatings have evolved to increase the mechanical toughness of the system, to provide corrosion protection at elevated temperatures, to provide specific surface textures, to provide a foundation for insulation systems, and to accept the rigors of specific construction techniques. Qualification test methods must give assurance that the basic system has the ability to survive the operating conditions after construction. Quality control (QC) testing must provide assurance that acceptable performance is consistently achieved throughout the course of mill and field application activities. Proper selection of test methods and proper interpretation of test results are essential components of comprehensive pipe coating and construction projects. This paper begins with a brief discussion of essential properties of all pipeline coatings, and a listing of multi-layer systems designed to meet specific needs. It then focuses on special considerations regarding application parameters for multi-layer systems that use fusion-bonded epoxy as the primer. These parameters determine long-term performance. A new interpretation of the simple water soak test can be a valuable tool in quality control testing.
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Turkalj, Tomás, Sebastian Cravero, and Gustavo Kissner. "Pipe Burst Pressure Estimation in Sour Environment Using Constant Load Fracture Toughness Tests." In CORROSION 2019. NACE International, 2019. https://doi.org/10.5006/c2019-13022.
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Abstract Sulfide stress cracking has special importance in the Oil and Gas (O&G) industry due to the considerable amount of hydrogen sulfide that may be present in the processed fluids. Furthermore, the increasing interest of the O&G industry on high grade tubulars to work at high pressure, makes the sulfide stress cracking phenomenon an important issue in the safe operational condition assessment of Oil Country Tubular Goods (OCTG). Consequently, the adequate determination of fracture toughness value (i.e.: K-mat) is of fundamental importance for fitness for purpose evaluation. Particularly, the fracture toughness of OCTG materials in aggressive media is usually determined using Double Cantilever Beam (DCB) specimens and the obtained Klimit values are the employed for fracture assessment. Although, Method D using DCB specimens have been and are the currently recognized testing methodology for pipe manufacturing QA/QC, its validity as a test to obtain the fracture resistance parameter for burst pressure estimation of flawed pipes remains uncertain and therefore alternative methods are being assessed. In the present paper, an experimental program is described. API 5CT-C110 grades were tested in aggressive environments. Klimit from conventional DCB tests and Kthreshold from Single Edge Notch Tension (SENT) specimens under constant loading are compared and discussed. The Kmat obtained from both testing techniques are used to calculate the burst pressure of flawed pipes using API 579(1) equations. The presented results and discussion allow incorporation of further insights on an alternative testing method and specimen geometry for brittle burst assessment of flawed pipes in an aggressive media.
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Letort, Voronique, Paul Mahe, Paul-Henry Cournede, Philippe De Reffye, and Brigitte Courtois. "Optimizing Plant Growth Model Parameters for Genetic Selection Based on QTL Mapping." In 2006 Second International Symposium on Plant Growth Modeling, Simulation, Visualization and Applications. IEEE, 2006. http://dx.doi.org/10.1109/pma.2006.35.
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Prom-on, Santitham, and Yi Xu. "The qTA toolkit for prosody: learning underlying parameters of communicative functions through modeling." In Speech Prosody 2010. ISCA, 2010. http://dx.doi.org/10.21437/speechprosody.2010-202.
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Hagiwara, Naoto, and Noritake Oguchi. "Fatigue Behavior of Line Pipes Subjected to Severe Mechanical Damage." In 1998 2nd International Pipeline Conference. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/ipc1998-2035.
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Fatigue tests were carried out on ERW line pipes 200 mm and 300 mm in diameter with a severe gouge in dent type defect. Hoop stress fluctuation between 15% and 30% of the yield stress of the pipe materials was applied by cyclic internal pressure loading. By the parameter Q, a function of defect size and fracture toughness, fatigue behavior could have been well explained. Fatigue behavior differed above and below the threshold Q (Qth. When Q<Qth, crack propagation was initially associated with ductile crack growth, and therefore, fatigue life, Nf, decreased to less than 1000 cycles. On the contrary, Nf was larger than 1000 cycles when Q≧Qth. Nf was predictable with a power law equation incorporating dent depth, gouge depth, and stress amplitude when Q≧Qth. A gouge in a dent with Q<Qth, requires immediate repair or replacement.
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Zimmer, Ulrich, and Mark Boyd. "The need for quantitative QC parameters for microseismic event identifications and locations." In SEG Technical Program Expanded Abstracts 2013. Society of Exploration Geophysicists, 2013. http://dx.doi.org/10.1190/segam2013-0120.1.
Full textReports on the topic "QTc parameters"
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Hulata, Gideon, and Graham A. E. Gall. Breed Improvement of Tilapia: Selective Breeding for Cold Tolerance and for Growth Rate in Fresh and Saline Water. United States Department of Agriculture, 2003. http://dx.doi.org/10.32747/2003.7586478.bard.
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The main objective of this project was to initiate a breeding program to produce cold-tolerant and salinity-tolerant synthetic breeds of tilapia, from a base population consisting of a four-species hybrid population created under an earlier BARD project. A secondary objective was to estimate genetic parameters for the traits growth rate under fresh- and salt-water and for cold tolerance. A third objective was to place quantitative trait loci that affect these traits of interest (e.g., growth rate in fresh-water, salt-water and cold tolerance) on the growing linkage map of primarily microsatellite loci. We have encountered fertility problems that were apparently the result of the complex genetic structure of this base population. The failure in producing the first generation of the breeding program has forced us to stop the intended breeding program. Thus, upon approval of BARD office, this objective was dropped and during the last year we have focused on the secondary objective of the original project during the third year of the project, but failed to perform the intended analysis to estimate genetic parameters for the traits of interest. We have succeeded, however, to strengthen the earlier identification of a QTL for cold tolerance by analyzing further segregating families. The results support the existence of a QTL for cold tolerance on linkage group 15, corresponding to UNH linkage group 23. The results also indicate a QTL for the same trait on linkage group 12, corresponding to UNH linkage group 4.
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Lee, Jusang, John E. Haddock, Dario D. Batioja Alvarez, and Reyhaneh Rahbar Rastegar. Quality Control and Quality Assurance of Asphalt Mixtures Using Laboratory Rutting and Cracking Tests. Purdue University, 2019. http://dx.doi.org/10.5703/1288284317087.
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The main objectives of this project were to review the available balanced-mix design (BMD) methodologies, understand the I-FIT and Hamburg Wheel Tracking Test (HWTT) test methods using INDOT asphalt mixtures, and to explore the application of these tests to both a BMD approach and as performance-related Quality Control (QC) and Quality Acceptance (QA) methods. Two QA mixture specimen types, plant-mixed laboratory-compacted (PMLC) and plant-mixed field-compacted (PMFC) were used in the determination of cracking and rutting parameters. Distribution functions for the flexibility index (FI) values and rutting parameters were determined for various mixture types. The effects of specimen geometry and air voids contents on the calculated Flexibility Index (FI) and rutting parameters were investigated. The fatigue characteristics of selected asphalt mixtures were determined using the S-VECD test according to different FI levels for different conditions. A typical full-depth pavement section was implemented in FlexPAVE to explore the cracking characteristics of INDOT asphalt mixtures by investigating the relationship between the FI values of QA samples with the FlexPAVE pavement performance predictions. The FI values obtained from PMFC specimens were consistently higher than their corresponding PMLC specimens. This study also found that FI values were affected significantly by variations in specimen thickness and air voids contents, having higher FI values with higher air voids contents and thinner specimens. These observations do not agree with the general material-performance expectations that better cracking resistance is achieved with lower air voids content and thicker layers. Additionally, PG 70-22 mixtures show the lowest mean FI values followed by the PG 76-22 and 64-22 mixtures. The same order was observed from the ΔTc (asphalt binder cracking index) of INDOT’s 2017 and 2018 projects. Finally, it was found that the HWTT showed reasonable sensitivity to the different characteristics (e.g., aggregate sizes, binder types, and air voids contents) of asphalt mixtures. Mixtures containing modified asphalt binders showed better rut resistance and higher Rutting Resistance Index (RRI) than those containing unmodified binders.
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Farahbod, A. M., and J. F. Cassidy. An overview of seismic attenuation in the Eastern Canadian Arctic and the Hudson Bay Complex, Manitoba, Newfoundland and Labrador, Nunavut, Ontario, and Quebec. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330396.
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In this study we investigated coda-wave attenuation (QC) from the eastern Canadian Arctic in Nunavut and the Hudson Bay complex including portions of northern Manitoba, Ontario, Quebec and Labrador. We used earthquake recordings from 15 broadband and 3 short period seismograph stations of the Canadian National Seismic Network (CNSN) and 29 broadband stations of the POLARIS network across the region. Our dataset is comprised of 637 earthquakes recorded between 1985 and 2021 with magnitudes ranging from 1.3 to 6.1, depths from 0 to 20 km and epicentral distances of 5 to 100 km. This gives a total of 246 high signal-to-noise (S/N) traces (S/N[lesser/equal]5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that in the northern section of the study area, the highest Q0 values (e.g., Q0 of 110 and 112) are at station POIN and station RES, respectively, which are located in the older Archean province. The lowest Q0 values that we find (e.g., Q0 of 55 and 61) are at station AKVQ and IVKQ respectively, located in northern Quebec. Smaller Q0 values for stations in the south are explained by the younger age of the rocks and proximity to the main fault systems. An average for all the data results in a Q relationship of QC = 82f1.08 for the frequency band of 2 to 16 Hz for the entire region.
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Farahbod, A. M., and J. F. Cassidy. An overview of seismic attenuation in the Northern Appalachians Seismic Zone, New Brunswick and Nova Scotia. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329702.
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In this study we investigated coda-wave attenuation (QC) from the northern Appalachian region of eastern Canada in the two provinces of New Brunswick and Nova Scotia. We used earthquake recordings from 8 broadband and 2 short period seismograph stations of the Canadian National Seismograph Network (CNSN) across the region. Our dataset is comprised of 476 earthquakes recorded between 1983 and 2021 with magnitudes ranging from 1.5 to 4.1, depths from 0 to 20 km (with the vast majority being &amp;lt;10 km) and epicentral distances of 5 to 100 km. This gives a total of 261 high signalto- noise (S/N) traces (S/N greater than or equal to 5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that in the northern New Brunswick, the lowest Q0 values (e.g., Q0 of 61) are at station KLN which is the closest station to the epicenter of the 1982 Miramichi earthquake (M 5.8). The highest Q0 values that we find (e.g., Q0 of 178) are at station GGN, located in the southern New Brunswick. Smaller Q0 values for stations in the north (closer to the Charlevoix-Kamouraska seismic zone or Miramichi source area) is explained by Jin and Aki's (1988) finding that Q0 is lower in the vicinity of large earthquakes. An average for all the data results in a Q relationship of QC = 99f0.96 for the frequency band of 2 to 16 Hz for the entire region.
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Paterson, Andrew H., Yehoshua Saranga, and Dan Yakir. Improving Productivity of Cotton (Gossypsum spp.) in Arid Region Agriculture: An Integrated Physiological/Genetic Approach. United States Department of Agriculture, 1999. http://dx.doi.org/10.32747/1999.7573066.bard.
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Objectives: We seek to establish the basis for improving cotton productivity under arid conditions, by studying the water use efficiency - evaporative cooling interrelationship. Specifically, we will test the hypothesis that cotton productivity under arid conditions can be improved by combining high seasonal WUE with efficient evaporative cooling, evaluate whether high WUE and/or evaporative cooling are based on specific physiological factors such as diurnal flexibility in stomatal conductance, stomatal density, photosynthetic capacity, chlorophyll fluorescence, and plant water status. Genes influencing both WUE and evaporative cooling, as well as other parameters such as economic products (lint yield, quality, harvest index) of cotton will also be mapped, in order to evaluate influences of water relations on these parameters. Approach: Carbon isotope ratio will be used to evaluate WUE, accompanied by additional parameters to elucidate the relationship between WUE, evaporative cooling, and cotton productivity. A detailed RFLP map will be used to determine the number, location, and phenotypic effects of genes underlying genetic variation in WUE between cultivated cottons, as well as test associations of these genes with traits of economic importance such as harvest index, lint yield, and lint quality. Major Conclusions: Productivity and quality of cotton grown under well-watered versus water-limited conditions was shown to be partly accounted for by different quantitative trait loci (QTLs). Among a suite of physiological traits often found to differ between genotypes adapted to arid versus well-watered conditions, genetic mapping implicated only reduced plant osmotic potential in improved cotton productivity under arid conditions. Our findings clearly implicate OP as a major component of cotton adaptation to arid conditions. However, testing of further physiological hypotheses is clearly needed to account for additional QTL alleles conferring higher seed-cotton yield under arid conditions, such as three of the five we found. Near-isogenic lines being made for QTLs discovered herein will offer a powerful new tool useful toward identification of the underlying gene(s) by using fine-scale mapping approaches (Paterson et al 1990). Implications: Adaptation to both arid and favorable conditions can be combined into the same genotype. We have identified diagnostic DNA markers that are being applied to creation of such desirable genotypes. Simultaneous improvement of productivity (and/or quality) for both arid and irrigated conditions will require more extensive field testing and the manipulation of larger numbers of genes, reducing the expected rate of genetic gain These difficulties may be at least partly ameliorated by efficiencies gained through identification and use of diagnostic DNA markers. Genomic tools and approaches may expedite adaptation of crops to arid cultivation, help to test roles of additional physiological factors, and guide the isolation of the underlying genes that protect crop performance under arid conditions.
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Farahbod, A. M., and J. F. Cassidy. An overview of seismic attenuation in the Charlevoix Seismic Zone, southern Quebec. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/332158.
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We investigate seismic attenuation characteristics of the Charlevoix Seismic Zone. This zone is located ~100 km downstream from Quebec City and is the most seismically active region of eastern Canada. We used earthquake recordings from 8 seismograph stations of the Canadian National Seismic Network (CNSN) across the region. Our dataset is comprised of 584 earthquakes recorded between 1992 and 2022 with magnitudes ranging from 2.0 to 5.4, depths from 0 to 30 km and epicentral distances of 5 to 100 km. This gives a total of 1490 high signal-to-noise (S/N) traces (S/N?5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that the highest Q0 (Q at 1 Hz) values are at station A11 (e.g., Q0 of 109), that is the farthest station from the 1663, M~7 earthquake (D=40 km), excluding the new station of CACQ. The lowest Q0 values that we find are at the station A16 (e.g., Q0 of 72) that is the second closest station to the epicenter of the 1663 earthquake (D=16 km) after station A61 (D=10 km). Also, we find the lowest overall average Q0 values at station A16 (e.g., Q0 of 72). In general, Q0 is lower in the vicinity of large earthquakes (Jin &amp; Aki, 1988). Therefore, the low Q0 values at station A16 may suggest that the 1663 earthquake is located slightly southeast of the catalog epicenter, considering high uncertainty associated with historic events. An average for all the data results in a Q relationship of QC = 81f1.06 for the frequency band of 2 to 16 Hz for the entire region.
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Farahbod, A., and J. F. Cassidy. Spatial and temporal variations in seismic coda Q attenuation in the lower St. Lawrence region, southeastern Quebec. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/332027.
Full textAbstract:
We investigate seismic attenuation characteristics of the Lower St. Lawrence seismic zone in southeastern Quebec. This zone is located ~400 km downstream from Quebec City and is between the Quebec North Shore and the Lower St. Lawrence. We used earthquake recordings from 5 broadband and 5 short period seismograph stations of the Canadian National Seismic Network (CNSN) across the region. Our dataset is comprised of 847 earthquakes recorded between 1985 and 2022 with magnitudes ranging from 2.0 to 5.1, depths from 0 to 30 km and epicentral distances of 5 to 100 km. This gives a total of 446 high signal-to-noise (S/N) traces (S/N?5.0) useful for QC calculation (with a maximum ellipse parameter, a2, of 100) across the region. Coda windows were selected to start at tc = 2tS (two times the travel time of the direct S wave), and were filtered at center frequencies of 2, 4, 8, 12 and 16 Hz. Our study reveals a consistent pattern. We find that the lowest overall average of Q0 (Q at 1 Hz) values are at the three stations (GSQ, ICQ and SMQ) within 100 km of a moderate earthquake of mN 5.1 in 1999 (e.g., Q0 of 81, 88 and 80, respectively). We determined temporal variations in attenuation following the 1999 earthquake. The overall average of Q0 decreased from 87 (before the mainshock) to 77 (GSQ, D=96 km), from 92 to 85 (ICQ, D=69 km) and from 88 to 82 (SMQ, D=73 km). These results are in agreement with global studies that show a decrease in Q0 following a significant earthquake, (e.g., M &amp;gt; 5) likely the result of increased fracturing and fluids in the epicentral region. An average for all the data results in a Q relationship of QC = 86f1.07 for the frequency band of 2 to 16 Hz for the entire region.
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Wei, Fulu, Ce Wang, Xiangxi Tian, Shuo Li, and Jie Shan. Investigation of Durability and Performance of High Friction Surface Treatment. Purdue University, 2021. http://dx.doi.org/10.5703/1288284317281.
Full textAbstract:
The Indiana Department of Transportation (INDOT) completed a total of 25 high friction surface treatment (HFST) projects across the state in 2018. This research study attempted to investigate the durability and performance of HFST in terms of its HFST-pavement system integrity and surface friction performance. Laboratory tests were conducted to determine the physical and mechanical properties of epoxy-bauxite mortar. Field inspections were carried out to identify site conditions and common early HFST distresses. Cyclic loading test and finite element method (FEM) analysis were performed to evaluate the bonding strength between HFST and existing pavement, in particular chip seal with different pretreatments such as vacuum sweeping, shotblasting, and scarification milling. Both surface friction and texture tests were undertaken periodically (generally once every 6 months) to evaluate the surface friction performance of HFST. Crash records over a 5-year period, i.e., 3 years before installation and 2 years after installation, were examined to determine the safety performance of HFST, crash modification factor (CMF) in particular. It was found that HFST epoxy-bauxite mortar has a coefficient of thermal expansion (CTE) significantly higher than those of hot mix asphalt (HMA) mixtures and Portland cement concrete (PCC), and good cracking resistance. The most common early HFST distresses in Indiana are reflective cracking, surface wrinkling, aggregate loss, and delamination. Vacuum sweeping is the optimal method for pretreating existing pavements, chip seal in particular. Chip seal in good condition is structurally capable of providing a sound base for HFST. On two-lane highway curves, HFST is capable of reducing the total vehicle crash by 30%, injury crash by 50%, and wet weather crash by 44%, and providing a CMF of 0.584 in Indiana. Great variability may arise in the results of friction tests on horizontal curves by the use of locked wheel skid tester (LWST) due both to the nature of vehicle dynamics and to the operation of test vehicle. Texture testing, however, is capable of providing continuous texture measurements that can be used to calculate a texture height parameter, i.e., mean profile depth (MPD), not only for evaluating friction performance but also implementing quality control (QC) and quality assurance (QA) plans for HFST.