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Surface properties of poly(bisphenol-A-carbonate)
The work presented in this thesis consists of several strands:
(a) the development of a technique to measure surface free energies of amorphous polymers
(b) an investigation of chemical polishing and
c) the problems of injection moulded polycarbonate.
Grooves inscribed in an amorphous polymer surface change in dimensions on thermal annealing, and this change observed by interferometry forms the basis of the surface free energy measurement technique. Stringent temperature control and accurate temperature monitoring during thermal annealing is an essential feature of this technique. A surface free energy of approximately 0.121 J m-2 (121 ergs cm-2) at 174°C was measured for polycarbonate using this method.
An increase in the polishing temperature the thinning rate but not the extent of polishing position of the sample during polishing was found rate of the viscous layer and hence polishing and was found to increase or etching. The to affect the growth etching phases. An activation energy of 26.0 kJ (mol)-1 was measured for the thinning process.
A high degree of molecular orientation and residual stress (a major reason for premature mechanical failure) was primarily attributed to cold moulding and poor mould design coupled with inadequate testing of, the finished product. The high birefringence observed in the moulding was predominantly attributed to molecular orientation and residual stress
Inelastic Final-State Interactions and Two-body Hadronic B decays into Single-Isospin channels
The role of inelastic final-state interactions in CP asymmetries and
branching ratios is investigated in certain chosen single isospin two-body
hadronic B decays. Treating final-state interactions through Pomeron and Regge
exchanges, we demonstrate that inelastic final state interactions could lead to
sizeable effects on the CP asymmetry.Comment: 23 pages, Latex, 1 eps-figur
Pengaruh Persepsi, Akreditasi Prodi, dan Promosi terhadap Keputusan Memilih Program Studi Akuntansi pada Politeknik Harapan Bersama
. This study aims to analyze the influence of students' perceptions, accreditation of study program, and promotion toward students'decision to choose Accounting study program in Polytechnic of Harapan Bersama. This is a quantitative research with sampling technique based on questionnaire and interview. Population in this research is 545 Accounting students from the class of 2016 in Polytechnic of Harapan Bersama. The number of samples in this study amounted to 231 respondents calculated using Slovin formula. The analysis tool used in this research is Multiple Regression Analysis using SPSS. The result shows that students' perception, accreditation of study program, and promotion have an effect on students' decision and accreditation becomes the most influential variable to choose Accounting study program in Polytechnic of Harapan Bersama
Alignments in quasar polarizations: pseudoscalar-photon mixing in the presence of correlated magnetic fields
We investigate the effects of pseudoscalar-photon mixing on electromagnetic
radiation in the presence of correlated extragalactic magnetic fields. We model
the Universe as a collection of magnetic domains and study the propagation of
radiation through them. This leads to correlations between Stokes parameters
over large scales and consistently explains the observed large-scale alignment
of quasar polarizations at different redshifts within the framework of the big
bang model.Comment: 12 pages, 5 figures, version published in PR
New Features of Extended Wormhole Solutions in the Scalar Field Gravity Theories
The present paper reports interesting new features that wormhole solutions in
the scalar field gravity theory have. To demonstrate these, we obtain, by using
a slightly modified form of the Matos-Nunez algorithm, an extended class of
asymptotically flat wormhole solutions belonging to Einstein minimally coupled
scalar field theory. Generally, solutions in these theories do not represent
traversable wormholes due to the occurrence of curvature singularities.
However, the Ellis I solution of the Einstein minimally coupled theory, when
Wick rotated, yields Ellis class III solution, the latter representing a
singularity-free traversable wormhole. We see that Ellis I and III are not
essentially independent solutions. The Wick rotated seed solutions, extended by
the algorithm, contain two new parameters a and \delta;. The effect of the
parameter a on the geodesic motion of test particles reveals some remarkable
features. By arguing for Sagnac effect in the extended Wick rotated solution,
we find that the parameter a can indeed be interpreted as a rotation parameter
of the wormhole. The analyses reported here have wider applicability in that
they can very well be adopted in other theories, including in the string
theory.Comment: 19 page
Mean-field methods in evolutionary duplication-innovation-loss models for the genome-level repertoire of protein domains
We present a combined mean-field and simulation approach to different models
describing the dynamics of classes formed by elements that can appear,
disappear or copy themselves. These models, related to a paradigm
duplication-innovation model known as Chinese Restaurant Process, are devised
to reproduce the scaling behavior observed in the genome-wide repertoire of
protein domains of all known species. In view of these data, we discuss the
qualitative and quantitative differences of the alternative model formulations,
focusing in particular on the roles of element loss and of the specificity of
empirical domain classes.Comment: 10 Figures, 2 Table
Factorization and Nonfactorization in B Decays
Using NLL values for Wilson coefficients and including the contributions from
the penguin diagrams, we estimate the amount of nonfactorization in two-body
hadronic B decays. Also, we investigate the model dependence of the
nonfactorization parameters by performing the calculation using different
models for the form factors. The results support the universality of
nonfactorizable contributions in both Cabibbo-favored and Cabibbo-suppressed B
decays.Comment: 17 pages, 5 figures, revte
Quality of life and glycemic control in adolescents with type 1 diabetes and the impact of an education intervention
Mostafa A Abolfotouh1,*, Mofida M Kamal2,*, Mohamed D El-Bourgy2,*, Sherine G Mohamed2,*1King Abdullah International Medical Research Center (KAIMRC), King Saud bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Kingdom of Saudi Arabia; 2Department of Health Administration and Behavioral Sciences, High Institute of Public Health, Alexandria University, Alexandria, Egypt; *All authors contributed equally to this workObjective: To assess quality of life (QoL) and glycemic control in adolescents with type 1 diabetes and to investigate the impact of an educational program.Methods: A quasiexperimental study with nonrandomized experimental and control groups was conducted in which a total of 503 adolescents with type 1 diabetes completed a questionnaire using the Diabetes Quality of Life Instrument for Youth. Adolescents were then assigned to experimental and control groups. The experimental group was subjected to four 120-minute sessions of an educational program over a period of 4 months. Extracted medical chart data included the duration of diabetes, insulin dosage, and most recent hemoglobin A1c levels. Analysis of covariance was used to detect the impact of intervention.Results: The overall mean QoL score (%) was 76.51 ± 9.79, with good QoL in 38% of all adolescents. Poorer QoL was significantly associated with older age (P < 0.001), more hospital admissions in the last 6 months (P = 0.006), higher levels of depression (P < 0.001), poor self-esteem (P < 0.001), and poor self-efficacy (P < 0.001). There was significant deterioration in all domains of QoL in the experimental group after intervention. However, this deterioration was significantly less severe than in the control group. Between-group effects on total knowledge, adherence to exercise, glucose monitoring, treatment, self-efficacy, family contribution to management, glycemic control, and satisfaction with life were significantly in favor of the experimental group.Conclusion: Education intervention for adolescents with type 1 diabetes could be a safeguard against possible deterioration in QoL and glycemic control over time.Keywords: adolescents, diabetes, QoL, glycemic, intervention&nbsp
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