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The overall aim of this thesis is to increase our knowledge of relevant exposure parameters when discussing possible health implication from exposure to radiofrequency electromagnetic fields (RF), especially effects that might occur at non-thermal levels. In this thesis an effort is made to broaden the exposure assessment and to take the exposure time into account and combine it with the Specific Absorption Rate (SAR) and the field parameters (electric and magnetic field strength) to approach a dose concept. In the first part of the thesis self-reported subjective symptoms among mobile phone users were studied. As a basis for this an epidemiological study among mobile phone users was completed with the main hypothesis that users of the digital transmission system GSM experience more symptoms than users of the older analogue NMT transmission system. The hypothesis was falsified, but an interesting side finding was that people with longer calling time per day experienced more symptoms than people with shorter calling time per day. The time-aspect (long duration phone call etc.) was also found to be relevant for the occurrence of symptoms in association with mobile phone use as well as duration of symptoms. The new suggested dosimetric quantity Specific Absorption per Day (SAD), in which both calling time per day as well as the measured SAR1g are included showed a stronger association to the prevalence of some of the symptoms, such as dizziness, discomfort and warmth behind the ear compared to both CT and SAR1g alone. In the second part whole body exposure conditions were considered. Methods to measure the induced current were examined in an experimental study, where different techniques were compared in different grounding conditions. The results were used in a study of operators of RF plastic sealers (RF operators) where the health status as well as the exposure were studied. The results showed that RF operators are a highly exposed group, which was confirmed by the fact that 16 out of 46 measured work places exceeded the ICNIRP guidelines. Headaches were found to be associated with the mean value of the time integrated E-field during a weld (E-weld) and the warmth sensations in the hands (warm hands) with the time integrated E-field exposure during one day (E-day). The general findings in this thesis indicated that time should be included in the exposure assessment when studying non-thermal effects such as subjective symptoms in connection with RF exposure. The thesis proposes two different methods for doing this, namely timeintegrated exposure [V/m x t and A/m x t] and dose [J/kg].

by Lee Wai Chi, Edwin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 115-125). / Acknowledgments --- p.I / List of figures --- p.II / List of tables --- p.III / List of graphs --- p.III / Abstract --- p.VIII / Chapter I.CHAPTER ONE --- Introduction --- p.1 / Chapter 1.1 --- Electromagnetic / Magnetic field in biological interventions --- p.1 / Chapter 1.2 --- Objective of the study --- p.4 / Chapter 1.3 --- Hypothesis of the study --- p.5 / Chapter II.CHAPTER TWO --- Literature Review --- p.6 / Chapter 2.1 --- Inflammation / Chapter 2.1.1 --- Models of studying tendon injuries --- p.6 / Chapter 2.1.2 --- Methods of measuring inflammation --- p.7 / Chapter 2.1.3 --- Treatments of soft tissue inflammation --- p.9 / Chapter 2.2 --- Aspects of electromagnetic and magnetic fields / Chapter 2.2.1 --- Applications of electromagnetic / magnetic fields in soft tissue inflammation --- p.12 / Chapter 2.2.2 --- Physiological effects of electromagnetic/magnetic fields / Chapter 2.2.2.1 --- Experiments on inflammation --- p.16 / Chapter 2.2.2.2 --- Experiments on soft tissue / tendon injuries --- p.16 / Chapter 2.2.2.3 --- Experiments on blood circulation --- p.18 / Chapter 2.2.3 --- Experiments with different parameter settings of PEMF / PMF in soft tissue inflammation --- p.19 / Chapter 2.2.4 --- Proposed mechanisms of electromagnetic/magnetic fields --- p.22 / Chapter III.CHAPTER THREE --- Methods and Materials --- p.23 / Chapter 3.1 --- Animal models --- p.23 / Chapter 3.2 --- Apparatus --- p.24 / Chapter 3.3 --- Treatment Regimen --- p.27 / Chapter 3.4 --- Assessments --- p.29 / Chapter IV.CHAPTER FOUR --- Histological Assessment --- p.30 / Chapter 4.1 --- Introduction --- p.30 / Chapter 4.2 --- Methods --- p.31 / Chapter 4.3 --- Results --- p.31 / Chapter 4.4 --- Discussions --- p.45 / Chapter V.CHAPTER FIVE --- Morphometrical analysis on tissue sections with immunochemical staining --- p.51 / Chapter 5.1 --- Introduction / Chapter 5.1.1 --- Different approaches in identification of macrophages --- p.51 / Chapter 5.1.2 --- Avidin-biotin enzyme complex assay --- p.52 / Chapter 5.2 --- Methods --- p.54 / Chapter 5.2.1 --- ABC method --- p.54 / Chapter 5.2.2 --- Morphometric analysis of tissue sections --- p.55 / Chapter 5.2.3 --- Statistical method --- p.56 / Chapter 5.3 --- Results / Chapter 5.3.1 --- Immunochemical results --- p.56 / Chapter 5.3.2 --- Morphometric results --- p.60 / Chapter 5.4 --- Discussions --- p.64 / Chapter VI.CHAPTER SIX --- Biochemical Assessments --- p.67 / Chapter 6.1 --- Water content / Chapter 6.1.1 --- Introduction --- p.67 / Chapter 6.1.2 --- Methods --- p.68 / Chapter 6.1.2.1 --- Water content measurement --- p.68 / Chapter 6.1.2.2 --- Statistical method --- p.69 / Chapter 6.1.3 --- Results --- p.72 / Chapter 6.1.4 --- Discussions --- p.77 / Chapter 6.2 --- Total collagen content / Chapter 6.2.1 --- Introduction --- p.81 / Chapter 6.2.1.1 --- Hydroxyproline as an indicator for collagen content assay --- p.81 / Chapter 6.2.2 --- Methods / Chapter 6.2.2.1 --- Hydrolysis method --- p.82 / Chapter 6.2.2.2 --- Standard-curve preparation --- p.83 / Chapter 6.2.2.3 --- Statstical method --- p.84 / Chapter 6.2.3 --- Results --- p.84 / Chapter 6.2.4 --- Discussions --- p.89 / Chapter VII.CHAPTER SEVEN --- Discussion --- p.92 / Chapter VIII.CHAPTER EIGHT --- Summary and Conclusions --- p.103 / Appendix A : Histological reagents preparations --- p.106 / Appendix B : Staining procedures for standard H & E --- p.107 / Appendix C : Immunochemical staining reagents preparations --- p.108 / Appendix D : Staining procedure for StreptABComplex / HRP --- p.110 / AppendixE : Biochemical reagents and preparations --- p.111 / Appendix F : Hydrolysis method for the tendon --- p.112 / Appendix G : Standard-curve of hydroxyproline --- p.113 / Appendix H : Determination of optimal hours for collagen hydrolysis --- p.114 / REFERENCES --- p.115

by Leung Shiu Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 137-146. / Chapter CHAPTER ONE --- Introduction --- p.1 / Chapter 1.1 --- Surgical intervention done for nerve injury --- p.1 / Chapter 1.2 --- Rehabilitation procedures after nerve injuries --- p.2 / Chapter 1.3 --- Frustrating result of recovery after nerve injuries --- p.3 / Chapter 1.4 --- Reasons for the poor results --- p.3 / Chapter 1.5 --- Objective of the study --- p.5 / Chapter 1.6 --- Hypothesis and organization of the study --- p.6 / Chapter CHAPTER TWO --- The effects of pulsed electromagnetic field on peripheral nerve regeneration --- p.8 / Chapter 2.1 --- Electrical field and nerve growth --- p.8 / Chapter 2.2 --- Experimental findings of effect of the electromagnetic field on peripheral nerve regeneration --- p.9 / Chapter 2.3 --- The diversity of interest --- p.17 / Chapter CHAPTER THREE --- Physiological effects of the pulsed electromagnetic field --- p.18 / Chapter 3.1 --- The conventional use of electromagnetic field in musculoskeletal rehabilitation --- p.18 / Chapter 3.2 --- The pulsed electromagnetic field --- p.18 / Chapter 3.3 --- Nature of the pulsed electromagnetic field with a carrier frequency of 27.12 MHz --- p.19 / Chapter 3.4 --- Therapeutic effects of the pulsed electromagnetic field --- p.20 / Chapter 3.5 --- Some experimental results of the pulsed electromagnetic field --- p.20 / Chapter 3.6 --- Discussion --- p.25 / Chapter CHAPTER FOUR --- Methology --- p.27 / Chapter 4.1 --- Experimental animals and aneasthesia --- p.27 / Chapter 4.2 --- Models of lesions --- p.28 / Chapter 4.3 --- Sample size and grouping of the experimental rats --- p.35 / Chapter 4.4 --- Pulsed electromagnetic field stimulation --- p.37 / Chapter 4.5 --- Methods of evaluating the nerve regeneration --- p.38 / Chapter 4.6 --- Statistical analysis --- p.53 / Chapter CHAPTER FIVE --- Results --- p.54 / Chapter 5.1 --- Directly repaired groups --- p.54 / Chapter 5.2 --- Crushed groups --- p.62 / Chapter 5.3 --- Artery bridge groups --- p.73 / Chapter 5.4 --- Sham operated groups --- p.84 / Chapter 5.5 --- Electron microscopic examination --- p.90 / Chapter 5.6 --- Summary of all the data --- p.94 / Chapter CHAPTER SIX --- Discuss ion --- p.96 / Chapter CHAPTER SEVEN --- Conclusion --- p.103 / Chapter 7.1 --- Restatement of the experimental objective and hypothesis --- p.103 / Chapter 7.2 --- Conclusion --- p.103 / Chapter 7.3 --- Suggestions for furthur research --- p.104 / Chapter 7.4 --- Clinical Implication --- p.105 / Chapter APPENDIX I --- Determination of the duration of survival of the experimental animal --- p.106 / Chapter APPENDIX II --- Perfusion of rats --- p.115 / Chapter APPENDIX III --- Horseradish peroxidase and tetramethvlbezindine reaction --- p.118 / Chapter APPENDIX IV --- Histology fixation --- p.120 / Chapter APPENDIX V --- Determination of the Position of the Histology Specimens --- p.121 / Chapter APPENDIX VI --- Raw Data Collected in the Experiment --- p.132 / REFERENCE --- p.137

by Chan Kam Wai Clifford. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 105-108). / Text in English; abstracts in English and Chinese. / by Chan Kam Wai Clifford. / Abstract --- p.i / Acknowledgements --- p.iii / Contents --- p.iv / List of Figures --- p.vii / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Motivations of the Project --- p.1 / Chapter 1.2 --- Historical Background --- p.1 / Chapter 1.3 --- Objective and Outline of Thesis --- p.3 / Chapter Chapter 2. --- Reviews on One-dimensional Dynamical Cavity --- p.4 / Chapter 2.1 --- Formalism --- p.4 / Chapter 2.2 --- Methods of Solution --- p.6 / Chapter 2.2.1 --- Phase Construction (R function) --- p.6 / Chapter 2.2.2 --- Instantaneous Mode Expansion --- p.12 / Chapter 2.2.3 --- Transformation Method --- p.15 / Chapter 2.3 --- Numerical Results --- p.15 / Chapter 2.3.1 --- Some Results using R function --- p.16 / Chapter 2.3.2 --- Some Results using Instantaneous Mode Decomposition --- p.24 / Chapter 2.3.3 --- Remarks on the Numerical Scheme used in Transformation Method --- p.28 / Chapter 2.3.4 --- "Comparisons of Results obtained by Phase Construction, In- stantaneous Mode Decomposition and Transformation" --- p.28 / Chapter 2.4 --- Conclusion --- p.30 / Chapter Chapter 3. --- Fixed-point Analysis for the One-dimensional Cavity --- p.31 / Chapter 3.1 --- Introduction --- p.31 / Chapter 3.2 --- What are the fixed-points? --- p.32 / Chapter 3.3 --- Characteristics of Fixed-points --- p.36 / Chapter 3.4 --- Fixed-points and Geometric Resonance --- p.39 / Chapter Chapter 4. --- Electromagnetic Field in an Undulating Spherical Cavity --- p.44 / Chapter 4.1 --- Classical Electromagnetic field theory --- p.44 / Chapter 4.2 --- Boundary Conditions --- p.46 / Chapter 4.3 --- The Motion of Cavity Surface --- p.47 / Chapter Chapter 5. --- Methods of Solution and Results to the Spherical Cavity --- p.48 / Chapter 5.1 --- Introduction --- p.48 / Chapter 5.2 --- Mode Decomposition and Transformation Method revisited --- p.49 / Chapter 5.2.1 --- Mode Decomposition --- p.49 / Chapter 5.2.2 --- Transformation Method --- p.50 / Chapter 5.2.3 --- Remarks on the use of Instantaneous Mode Expansion and Transformation Method --- p.51 / Chapter 5.3 --- The Ge(z) function --- p.52 / Chapter 5.3.1 --- The Ge(z) function as a solution of the scalar wave equation --- p.52 / Chapter 5.3.2 --- Numerical Results --- p.54 / Chapter 5.4 --- The Me(z) function --- p.60 / Chapter 5.4.1 --- Formalism --- p.60 / Chapter 5.4.2 --- Comparison of Me(z) with Ge(z) --- p.62 / Chapter 5.4.3 --- Numerical Results --- p.63 / Chapter 5.5 --- Conclusions and Discussions --- p.93 / Chapter 5.5.1 --- Geometric Resonances --- p.93 / Chapter 5.5.2 --- Harmonic Resonances --- p.94 / Chapter Chapter 6. --- Conclusion --- p.95 / Appendix A. Electromagnetic Field in Spherical Cavity --- p.97 / Chapter A.1 --- Field Strength --- p.97 / Chapter A.2 --- Field Energy --- p.98 / "Appendix B. Construction of Ψe(r,t) by G(z)" --- p.100 / Appendix C. The Arbitrary Part GH(z) of Ψe(r，t) --- p.103 / Bibliography --- p.105

The ultra-strong magnetic fields of magnetars have profound implications for their radiative phenomena. We study the dynamics of strong magnetic fields inside and outside magnetars. Inside the magnetar, the strong magnetic stress can break the crust and trigger plastic failures. The interaction between magnetic fields and plastic failures is studied in two scenarios: 1. Internal Hall waves launched from the core-crust interface can initiate plastic failures and lead to X-ray outbursts. 2. External Alfven waves produced by giant flares can also initiate crustal plastic failures which dissipate the waves and give rise to delayed thermal afterglow. The crustal dissipation of Alfven waves competes with the magnetospheric dissipation outside the magnetar. Using a high order simulation of Force-Free Electrodynamics (FFE), we found that the magnetospheric dissipation of Alfven waves is generally slow and most wave energy will dissipate inside the magnetar.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

<p>The overall aim of this thesis is to increase our knowledge of relevant exposure parameters when discussing possible health implication from exposure to radiofrequency electromagnetic fields (RF), especially effects that might occur at non-thermal levels.</p><p>In this thesis an effort is made to broaden the exposure assessment and to take the exposure time into account and combine it with the Specific Absorption Rate (SAR) and the field parameters (electric and magnetic field strength) to approach a dose concept.</p><p>In the first part of the thesis self-reported subjective symptoms among mobile phone users were studied. As a basis for this an epidemiological study among mobile phone users was completed with the main hypothesis that users of the digital transmission system GSM experience more symptoms than users of the older analogue NMT transmission system.</p><p>The hypothesis was falsified, but an interesting side finding was that people with longer calling time per day experienced more symptoms than people with shorter calling time per day. The time-aspect (long duration phone call etc.) was also found to be relevant for the occurrence of symptoms in association with mobile phone use as well as duration of symptoms. The new suggested dosimetric quantity Specific Absorption per Day (SAD), in which both calling time per day as well as the measured SAR1g are included showed a stronger association to the prevalence of some of the symptoms, such as dizziness, discomfort and warmth behind the ear compared to both CT and SAR1g alone.</p><p>In the second part whole body exposure conditions were considered. Methods to measure the induced current were examined in an experimental study, where different techniques were compared in different grounding conditions. The results were used in a study of operators of RF plastic sealers (RF operators) where the health status as well as the exposure were studied. The results showed that RF operators are a highly exposed group, which was confirmed by the fact that 16 out of 46 measured work places exceeded the ICNIRP guidelines. Headaches were found to be associated with the mean value of the time integrated E-field during a weld (E-weld) and the warmth sensations in the hands (warm hands) with the time integrated E-field exposure during one day (E-day).</p><p>The general findings in this thesis indicated that time should be included in the exposure assessment when studying non-thermal effects such as subjective symptoms in connection with RF exposure. The thesis proposes two different methods for doing this, namely timeintegrated exposure [V/m x t and A/m x t] and dose [J/kg]. </p>

A.D. Berk. / "February 11, 1955." / Bibliography: p. 59. / Army Signal Corps Contract DA36-039 SC-64637 Project 102B Dept. of the Army Project 3-99-10-022

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