Advanced Quantitative Echocardiography: Guiding Therapy for Heart Failure

The aim of this thesis was to investigate the potential application of echocardiography for an efficient management of heart failure (HF) patients. The thesis is presented in four parts as follows: part I (introduction), part II (assessment of global left ventricular systolic function), part III (assessment of cardiac resynchronization therapy), and part IV (summary and conclusion). The general introduction (Chapter 1) of this thesis provides an overview of HF management using cardiac resynchronization therapy (CRT). HF constitutes an increasing and prevalent health burden worldwide. Echocardiography is a versatile non-invasive imaging modality that can be used for an efficient management of HF by proper diagnosis and guiding therapeutic interventions. Accurate assessment of left ventricular (LV) volumes and ejection fraction (LV-EF) would have important prognostic implications. CRT is a technique in which atrio-biventricular pacing is used to improve clinical and echocardiographic outcome for selected HF patients. The rationale behind CRT is the restoration of atrio-ventricular, inter-ventricular and intra-ventricular synchrony by stimulation of the delayed ventricular sites. It results in effective LV filling and emptying, reducing ventricular size improving ventricular geometry and most importantly improves survival. However, these impressive results of CRT are not seen in ~30% of patients. There are several unresolved and potentially other undetected reasons behind the high percentage of CRT failure. The echocardiography may improve the efficacy of CRT by reducing the non –response rate. The potential fields of echocardiography are: proper selection of candidates; optimization of atrio- and inter-ventricular pacing; guiding lead placement and proper detection of the response to CRT by accurate assessment of atrial and ventricular structure and function. These fields are mostly the topics of this thesis

Clinical and financial evaluation of patients within a diagnosis related group

The purpose of this study is to evaluate financial and clinical data of patients within a selected DRG. The data obtained from such analysis will be used to design a system whereby clinical pharmacists may improve the hospital\u27s reimbursement potential. Based upon Upton\u27s proposed plan, this study is designed to evaluate all DRGs in a community hospital in an attempt to focus on those DRGs which represent the greatest financial pressure to the pharmacy department and, therefore, to the institution. Clinical and financial data of patients within the expensive DRG, will be collected from their medical and financial records for subsequent statistical analysis with special consideration to pharmacy charges. The ultimate objective of this study, though, is to provide a list of measures or parameters that may affect the patient\u27s hospital charges. Using these parameters, the clinical pharmacists will be able to intensify their monitoring of patients with high pharmacy charges in an attempt to reduce their impact on patients\u27 charges. This study was designed to review and analyze DRGs at St. Joseph\u27s Hospital, in Stockton, Californias. The main objective was to determine the relationship between clinical and financial data for patients within a DRG. The second objective was to identify patient-specific information that may reflect high pharmacy charges and the need for clinical pharmacy intervention. The third objective was to propose criteria that may predict which patients need to be monitored in an attempt to control pharmacy charges within a selected DRG category

Start-up transient model for a refrigerant condenser

A one-dimensional start-up transient model for a portion of the refrigeration system used in typical residential air conditioners was developed in this study. The model was limited to three components: the compressor, the condenser, and the expansion valve. The main objective of this study is to introduce numerical methods and new solution schemes which can be used to give accurate, detailed predictions of the fast transient behavior inside the condenser, and to predict the development of the superheated, two-phase, and subcooled sections within the condenser as a function of position and time. Homogeneous and separated two-phase flow models are used to describe the two-phase flow. The mathematical formulation of this model is based on mass, momentum, and energy balances with associated heat transfer and friction relationships. The results of two different case studies are presented. In case study #1, air is used as the working fluid, while in case study #2, a refrigerant is used and the results are compared with a reported analytical model presented by Dhar (Ref.2). The effects of the wall thermal capacity and the different two-phase flow models on the system start-up transient behavior are also discussed.Includes bibliographical references

Evaluating cholesterol screening in a community pharmacy

The purpose of this research project was to evaluate the role of the community pharmacist in screening, identifying, and referring ambulatory patients with high total blood cholesterol (TBC) in a community pharmacy. Fifty seven patients, out of 241 initially screened individuals, met the study inclusion criteria and were accepted into this study. Of these 57 patients, 51 patients completed the six month study period. The normal population group consisted of 164 participants with TBC \u3c 200 mgjdL at the initial cholesterol testing (visit 1). The drop out group represented six patients who failed to continue attending the two follow up tests (visit 2 and 3). For screening purposes, a non-fasting whole blood sample was used to measure TBC using the Boehringer Mannheim Reflotron analyzer. The project was evaluated based on mean TBC levels obtained during the initial screening and the two follow up tests, pre-test and post-test scores, behavior and lifestyle changes, and the number of patients who received a physician\u27s order for lipid analysis as a result of initial screening results. In addition, influence of age and educational background on lowering TBC in visits 2 and 3, patient acceptance of blood screening in a community pharmacy and willingness to pay for this service in the future were also determined. To assess the level of significance among the means of the tested parameters, both parametric (one-way analysis of variance, Scheffe\u27s post hoc test and two sample t-test) and non-parametric statistics (Mann-Whitney and chi-square test) were used at a probability level of less than 0.05. There was a significant difference in mean TBC levels between visit 1 and 2, and between visit 1 and 3 (P\u3c 0.01). However, no statistically significant difference was found between visit 2 and 3 (P= 0.48). In addition, there was no significant difference in the incidence of high blood cholesterol in terms of gender or age difference at the initial screening. Further, mean TBC levels between males and females remained statistically insignificant during the two follow up tests. However, younger patients were able to lower their mean TBC level in visit 2 and 3 compared with older patients (P=\u3c 0.031). The one-way analysis of variance results showed that there was no statistically significant difference in TBC changes during the three visits by subjects categorized by educational background levels. Patient\u27s attitude toward the idea of blood test measurement in community pharmacies was positive. Ninety eight percent of the study group stated that they strongly liked such an idea, 92.16% expressed a willingness to pay an average of $4.55 (range$3 or less to $10), and all agreed that it was a convenient service for them. It was concluded that cholesterol screening in this community pharmacy was effective and acceptable, and may prove to be financially feasible when effectively planned and marketed. This service provides the community pharmacist with an opportunity to offer a unique patient-oriented public service

Computational Modelling of Thermal Transport using Spectral Phonon Boltzmann Transport Equation

Lattice vibration is the main microscopic mechanism for thermal transport in dielectric materials. The convenience of the analysis of atomic vibrations in the reciprocal space, motivated by the pioneering work of Debye and Peirels, made phonon transport theory is one of the standard paradigms adequate to study the microstructure and stoichiometry effects on thermal transport phenomena at mesoscale. UO2 is of theoretical as well as technological importance. The characteristic thermal transport phenomena at short length-scale (~ nanometer) and time-scale (~ picosecond) associated with radiation dictate close examination of available theoretical models and solution methods for thermal conductivity prediction, in addition to the validity of introduced approximations. By the virtue of INS experimental technique with powerful resolution, a direct benchmarking of simulated phonon properties results has been made possible. This provides by far a more accurate assessment criteria than thermal conductivity, and pave the way for founding sophisticated models of radiation effects on thermal transport with theoretical supports, beyond the currently available empirical or phenomenological models that succeed to reproduce the right macroscopic behavior in many cases just because of error cancellations and/or the use of adjustable parameters. Within time dependent perturbation theory (Fermi golden rule) framework, to represent the collision term of the semi-classical phonon Boltzmann Transport Equation, the bottleneck of the employed approach is to calculate intrinsic and extrinsic scattering rates of phonon modes. Being a highly correlated system with 5f electrons and magnetic phase transition at very low temperature, there are several challenges facing first-principle methods to leverage accurate phonon properties at finite temperature and imperfect structure that still need to be overcome. Moreover, it is common that using 3-phonon processes alone in other dielectrics overestimates lattice thermal conductivity at high temperatures (due to ignoring higher order phonon-phonon interactions), however, previous computational studies predicted values for UO2 conductivity lower than experiment by a factor of two about one third of the melting temperature. These observations assert the necessity of firstly investigating the impact of different introduced approximations for the calculation of intrinsic lattice thermal conductivity, to analyze the crucial parameters and to better understand this anomalous prediction. In this investigation, we present a critical assessment of several common approximations for the calculations of lattice thermal conductivity using spectral phonon Boltzmann Transport Equations. These approximations pertain to dispersion anisotropy and relations, Brillouin zone structure, and the coupling between the scattering rates of phonon normal modes. By employing harmonic approximation—perturbation theory to describe the scattering rates of a model system, FCC argon, our calculations show that widely spread approximations such as isotropic continuum and Single Mode Relaxation Time (SMRT) are not reliable, even for the case of cubic systems with their high symmetry properties. The success of these approximations is demonstrated to be a direct result of error cancellations. In addition, we show the essential importance of considering coupling terms at phonon mode level, and not in a statistical average sense as, for example, Callaway’s model does. By taking into account the coupling terms, the results evidence the crossover between the heat diffusion mediated by particle-like phonons (incoherent scattering) and the wave-like heat propagation due to phonon coherent scattering. Furthermore, this made possible revealing thermal conductivity anisotropy in cubic crystals. Finally, sensitivity of conductivity prediction to phonon spectrum is found to change over temperature. On the other hand, we challenge the widespread consensus that phonon-phonon interactions are inactive in the low temperature regime, which, in past investigations, led to the belief that the peak in lattice thermal conductivity (versus temperature) occurs because of two competing scattering mechanisms, umklapp and defect scattering mechanisms, dominant above and below the peak temperature, respectively. To the contrary, our study demonstrates that peak thermal conductivity, versus temperature, can still be obtained solely based upon phonon-phonon processes. This finding has been aided by considering the inelastic nature of 3-phonon scattering through applying energy conservation rule in a statistical average sense. Among the different statistical distributions examined to represent the regularized Dirac delta function appearing in Fermi Golden Rule, adopting Lorentz distribution, in analogy with phonon normal mode eigenenergy broadening due to the leading term of crystal anharmonicity, can uniquely reproduce the attained behavior in the low temperature limit. Simulation results, based on our adjustable parameter-free model, evidence that the heavy tail of the Lorentz distribution is the key. Unlike other models that similarly employ harmonic approximation—perturbation theory to describe the 3-phonon scattering rates, a maximum in the intrinsic thermal conductivity at finite temperature was strikingly obtained in our investigation, without the need to consider multi-step or higher order phonon interactions. By applying our approach to solid argon, considering only three-phonon scattering, good agreement with experiment was achieved for the first time in both the low (T2) and high (T-1) temperature regimes simultaneously, in addition to the peak temperature (~ 8 K). This indicates that phonon-phonon interactions can solely be used to interpret the shape of the conductivity versus temperature curve for the case of Ar, without the need to invoke defect or boundary scattering in the low temperature regime. At the same time, by employing the same computational model for UO2, the results show that phonon-phonon interactions are not predominant in the sub-peak regime, which suggest that phonon-magnon interactions should be considered at low temperature to reproduce experimental results

‘INVESTIGATING THE EFFECT OF MISPLACEMENT STRESS ON CHANGING SYNTACTIC CATEGORIES OF WORDS (A CASE STUDY OF ALBAHA UNIVERSITY STUDENTS AT TERTIARY LEVEL - FACULTY OF SCIENCE AND ARTS - ALMANDAQ)’

The purpose of this study is to look into the effect of misplacement stress on changing syntactic categories of words used by Albaha University students at the Faculty of Science and Arts – Almandaq at the tertiary level. The aim of this research is to demonstrate the effects of misplaced stress on the syntactic categories of words (verbs and nouns). To get and process the gathered data, a descriptive qualitative method is used. The study's population is third-year English department students' for the academic year 2021–2022. In the first semester, the students take a phonology course, which is beneficial to our study. The study's sample included 20 male students. The researcher designed an oral recorded test and a written test to collect the data. To measure the acoustic properties of English words for the oral recorded test, the data was analyzed using "Praat soft wave." For the written test, the SPSS program was used. The findings revealed a clear deficiency in the students' ability to manage stress effectively. This failure attributed to a lack of knowledge about stress placement and its effect on syntactic category. Furthermore, students do not get enough practice and feedback on stress placement while speaking and reading activities. Keywords: Stress Placement, Word Stress, Syntactic Category, Albaha University   Students

EXPLORING THE IMPACT OF FREE VOLUNTARY READING IN UPGRADING UNIVERSITY STUDENTS' CREATIVE WRITING AT AL BAHA UNIVERSITY

The purpose of this study is to investigate the impact of free voluntary reading in upgrading university students' creative writing at Al-Baha University. It introduces the types of free voluntary reading that can be employed by the students. In order to achieve this, thirty students at Al-Baha University enrolling in the BA program in English department were chosen randomly. The descriptive analytic method then applied in this study. Pre-test and post-test designed for the students and a questionnaire directed to the teachers were used as tools of collecting data. Finally, the results revealed that free voluntary reading plays critical roles in upgrading the students’ creative writing. Also, the teachers highly appreciate the contributions of free voluntary reading materials in pushing forward the students' achievement. Keywords: free voluntary reading, university students, BA program, creative writin