Joint Modelling Of Longitudinal and Survival Data in Presence of Cure Fraction with Application to Cancer Patients’ Data

Analyses involving longitudinal and time-to-event data are quite common in medical research. The primary goal of such studies to simultaneously study the effect of treatment on both the longitudinal covariate and survival. Often in medical research, there are settings in which it is meaningful to consider the existence of a fraction of individuals who have little to no risk of experiencing the event of interest. In this thesis, we focus on such settings with two different data structures. In early part of the thesis, we focus on the use of a cured fraction survival models performed in a population-based cancer registries. The limitations of statistical models which embodied the concept of a cured fraction of patients lack flexibility for modelling the survival distribution of the uncured group; lead to a not good fit when the survival drops rapidly soon after diagnosis and also when the survival is too high. In this study, a cure mixture model is enhanced by developing a dynamic semi-parametric exponential function with a smoothing parameter. The latter (major) part of the thesis focuses on modelling the longitudinal and the survival data in presence of cure fraction jointly. When there are cured patients in the population, the existing methods of joint models would be inappropriate, since they do not account for the plateau in the survival function. We introduce a new class of joint models in presence of cure fraction. In this joint model, the longitudinal submodel is a combination of a random mixed effect model and a stochastic process. A semi-parametric submodel is also proposed to incorporate the true longitudinal trajectories and other baseline time (dependent or independent) covariates. This model accounts for the possibility that a subject is cured, for the unique nature of the longitudinal data, and is capable to accommodating both zero and nonzero cure fractions. We generalize the two submodels to be multidimensional to investigate the relationship between the multivariate longitudinal and survival data. Bayesian approach was applied to the data using a conjugate and non-conjugate prior families to obtain parameter estimates for the proposed models. Gibbs sampling scheme is modified for fitting the joint model. Metropolis Hasting and Adaptive Rejection Sampling steps are used to update the Markov chain to estimate parameter whose full conditional densities can not be sampled efficiently from the existing methods, leading us to propose efficient proposal densities. The simulation studies demonstrate that the joint modelling method results in efficient estimates and good coverage for the population parameters. The analysis of cancer patient’s data indicates that when ignoring the association between the longitudinal and the survival data would lead to biased estimates for the most important parameters

Hysteron-proteron: A Polyfunctional Rhetorical Device – with Reference to Arabic-English Translation

Hysteron-proteron is one of the rhetorical devices present in all literary works and in almost all literate cultures.Linguistically, it is considered a kind of inversion, topicalization or permutation that occurs on the sentence level and involves deviation in the syntagmatic progression of sentences as well as a semantic shift encompassing scope, focus and emphasis (Jakobson 1972: 78-80) besides fulfilling certain grammatical processes such as interrogation and passivization (Jack et al. 1989).Literarily, hysteron-proteron has a great aesthetic and poetic relevance as it is one of the rhetorical devices that can structurally modify both the texture and sense of the text according to the writer’s taste and intention. In other words, it offers one of the stylistic options that will consequently exercise certain pragmatic impact on the reader.It goes without saying, however, that by virtue of its strong affinity to syntax, semantics and style, hysteron-proteron usually involves translation problems which acquire more salience when the languages hold two diametrically opposing standpoints as is the case with Arabic and English.After expounding hysteron-proteron and, diagrammatically, illustrating its polyfunctionality, an account is provided on its occurrence in prose, poetry and in Arabic sacred literature i.e., the Qur’an, tackling its deeper sedimented layers in the Arab mind. The paper also legislates for the unmistakable impact of Western style of literary expression on some Arabic narrative texts. This just projects one more benefit of translation when used as a probing device in detecting literary borrowing through awkward or blind literal rendering of purposefully-disrupted word-order in English into Arabic or vice versa.L’hystéron-protéron est une façon rhétorique dans les travaux littéraires et presque dans toutes les sociétés avec écriture.D’un point de vue linguistique, il s’agit d’une forme d’inversion, de topicalisation ou de permutation qui se produit au niveau de la phrase et inclut une déviation dans la progression syntagmatique des phrases, de même qu’un changement sémantique englobant le champ, la mise en évidence et en relief (Jakobson 1972 : 78-80), en plus de jouer un rôle dans certains procédés grammaticaux comme l’interrogation et la passivation (Jack et al. 1989).L’hystéron-protéron a une grande importance esthétique et poétique et constitue l’une des façons rhétoriques qui peut modifier structuralement la structure et le sens d’un texte en fonction des intentions de l’auteur. En d’autres termes, il s’agit d’un choix stylistique qui exerce une influence pragmatique sur le lecteur.Cependant, son fort lien avec la syntaxe, la sémantique et la stylistique engendre des difficultés de traduction qui sont plus saillantes lorsque les langues ont des positions diamétralement opposése, comme l’arabe et l’anglais.Après avoir exposé l’hystéron-protéron et illustré sa polyfonction, sa présence dans la prose, la poésie et la littérature arabe sacrée (par exemple le Coran), l’article donne aussi l’influence du style occidental sur l’expression littéraire de textes narratifs arabes

Are Graduates from the Public Authority for Applied Education and Training in Kuwaiti Meeting Industrial Requirements?

This paper examined those factors that had a direct impact on the quality of graduates from the Public Authority of Applied Education and Training (PAAE&T) in Kuwait. The study also report the degree to which the graduates met the requirements of local employers. The study consisted of: a review of the literature; a questionnaire given to a sample of students in selected departments; interviews with department heads at the PAAE&T; deans of related colleges and institutions; deans of industrial liaison offices in the selected sample of the PAAE&T; and supervisors in industry who have direct contact with prospective PAAE&T graduates; and employed graduates. This paper concluded that there was a need to develop a proper labour strategy to ensure that graduates from PAAE&T are equipped with the required knowledge, skills and attitudes to meet industry and business needs. Keywords: Vocational and technical Education, developing Indigenous Manpower, Interaction between vocational and technical education and local industries and business, Kuwait.

The Cosmological Redshift Manifests the Curvature and Interpreted as a Degree of Hyperbolicity of the Spacetime

Hubble’s law describes a uniformly expanding flat universe. Hubble’s law doesn`t explain why distant objects were receding fastest. There is an approximately linear relationship between redshift and distance at small scales for all the FLRW models, and departures from linearity at larger scales can be used to measure spatial curvature. Locally the spacetime is flat. For distant objects, the imprint of the curvature is significant, where the spacetime does no longer remain flat. The redshifts from such distant objects increase according to the increase in the curvature of the hyperbolic spacetime. The cosmological (gravitational) redshift can be interpreted as a degree of the hyperbolicity of the curved spacetime.  The Universe is globally hyperbolic as we did prove mathematically [S. A. Mabkhout, Phys. Essays, 25, 112 (2012)]. Such a solution predicts the equation of state of cosmology P = - . The hyperbolic structure of the spacetime–not dark energy- causes the accelerated expansion of the universe. Thus, in our non-existing dark energy hyperbolic universe, the increase in the cosmological redshift can only account for the increase in curvature that causes such an accelerated expansion relative to the observer. We developed [S. A. Mabkhout, Phys. Essays, 26,422 (2013)] the equation of motion in the hyperbolic spacetime, that describes the speed up motion in the hyperbolic spacetime and predicts the flat rotation curve. In the hyperbolic spacetime, the free fall due to the curvature, causes the non-decreasing speed of the galaxies for large r. Thus, the Doppler redshift manifests such curvature. As an object is far distant apart, as much the spacetime appears relatively hyperbolic curved with a high redshift. Its velocity relatively appears to exceed the speed of light "c" due to the assumption of flat spacetime

ACADEMIC STAFF PROMOTION SYSTEM AND ITS INFLUENCE ON THE QUALITY OF VOCATIONAL AND TECHNICAL EDUCATION - COLLEGE OF TECHNOLOGICAL STUDIES, AS A CASE KUWAIT

The need to enhance local capability is one of most Kuwaiti government priorities that is embodied in the overall governmental plan. In fact, the Kuwaiti government has exerted efforts to forge the College of Technological Studies, CTS, in order to equipped students with the knowledge, skills and attitudes that are required by essential sector in the country’s economy (e.g., Oil and Electricity and Water). However, the success of the College of Technological Studies in achieving its objectives would rely on the competencies of the CTS management and academic staff in meeting industrial requirements. The shaping and enhancing of student’s ability in managing, maintaining, and adapting the imported technology in industries would rely on the level of academic staff knowledge, skills, experience, and attitude in meeting industrial requirements. The efficiency of the promotion system for academic staff would indeed contribute significantly to shaping the standard of the CTS graduates. The need to absorb and evaluate the current status of the CTS academic staff promotion system must be one of highly management priority in order to achieve the CTS overall objectives. The aim of this paper is to identify and examine the efficiency of the academic staff promotion system. Several issues would be investigated and examined. Among which: the criteria’s applied in selected and approving academic journals, the criteria’s required for promoting academic staff, work ethics and its relation to the academic staff promotion system, and the obstacles that might face the CTS management in applying the academic staff promotion system. The paper would conclude that unless the management of the CTS realised and appreciate the significant role of the academic staff promotion system, industries would continue to rely on expatriate for years ahead.  Article visualizations

Labor regulation and unemployment : the case of Tunisia

Using a different database of labor regulation, we sketch the relationship between labor market flexibility and unemployment in Tunisia during the period 2000-2013. The results of the study find no link between labor regulation and unemployment. The main finding from the dynamic panel estimation is that the labor regulation composite indicator used does not have a statistically significant association with the unemployment rate for the selected 115 developing countries. However, there is a direct link between the firing and hiring regulation and unemployment. In addition, the interactive variable between these indicators and the dummy variable for Tunisia doesn’t seem to explain why unemployment is higher in Tunisia than in other countries. Regulation has no adverse effect on aggregate unemployment.peer-reviewe

Human Fetal Hemoglobin Expression and Erythrocytic Indices in Different Groups Among U.A.E Population

Molecular analysis has revealed that a variety of hemoglobin molecules are produced in humans. All are tetramers consisting of numerous combinations of seven distinct polypeptide chains, each encoded by a separate gene. Fetal hemoglobin is one of these tetramers that by eight weeks of gestation replace the embryonic hemoglobin forms. Fetal hemoglobin is the major hemoglobin in fetal life. it\u27s concentration in blood decreases after birth to less than 2 per cent of the total hemoglobin by 6 months of age. However, in some cases fetal hemoglobin persist to synthesize in adult life in abnormal concentrations. Our study concerned the fetal hemoglobin expression in four different groups (normal group, anemic group, pregnant women group, and thalassemic patients group). The results show that fetal hemoglobin in the normal group was in the normal ranges observed in other populations, there is no big differences between males and females, and there was no correlation between fetal cells level and fetal hemoglobin production. In the anemic group there was more fetal hemoglobin present than in the normal group and there was no differences between males and females. Fetal hemoglobin continue to be expressed in anemic conditions, even when due to genetic or environmental factors. The fetal hemoglobin production in pregnant women is heterogenous and is still within the normal female range that was obtained in our study, this indicates that there are no sex linked genetic factors modulating the fetal hemoglobin expression. The study. shows also, that fetal hemoglobin production is heterogenous in beta thalassemic patients and there were large variations betvleen the heterozygous and the homozygous patients. The large differences in expression within a homogenous genetic population and, sometimes within the same family, imposes the problem of fetal hemoglobin regulation and leads us to assume that fetal hemoglobin production is under at least 2 determinants: genetic, nongenetic

Machine Learning for Biometrics

Biometrics aims at reliable and robust identification of humans from their personal traits, mainly for security and authentication purposes, but also for identifying and tracking the users of smarter applications. Frequently considered modalities are fingerprint, face, iris, palmprint and voice, but there are many other possible biometrics, including gait, ear image, retina, DNA, and even behaviours. This chapter presents a survey of machine learning methods used for biometrics applications, and identifies relevant research issues. We focus on three areas of interest: offline methods for biometric template construction and recognition, information fusion methods for integrating multiple biometrics to obtain robust results, and methods for dealing with temporal information. By introducing exemplary and influential machine learning approaches in the context of specific biometrics applications, we hope to provide the reader with the means to create novel machine learning solutions to challenging biometrics problems