211 |
Electrical characterization of SiC/Si heterostructure by ion implantation of carbon.January 1996 (has links)
by Ho Lai-Ching. / Year shown on spine: 1997. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves xiii-xvii). / ACKNOWLEDGMENT --- p.I / ABSTRACT --- p.II / CONTENTS --- p.IV / FIGURE CAPTIONS --- p.VI / TABLE CAPTIONS --- p.IX / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 --- A BRIEF REVIEW OF ION BEAM SYNTHESIS OF SiC --- p.5 / Chapter CHAPTER 3 --- SAMPLE PREPARATION AND MEASUREMENT METHODS --- p.9 / Chapter 3.1 --- Sample Preparation --- p.9 / Chapter 3.1.1 --- MEVVA Implantation --- p.9 / Chapter 3.1.2 --- Implantation Conditions --- p.12 / Chapter 3.2 --- Characterization Methods --- p.14 / Chapter 3.2.1 --- Spreading Resistance Profiling (SRP) --- p.14 / Chapter 3.2.1.1 --- Principle of SRP Measurement Method --- p.14 / Chapter 3.2.1.2 --- Sample Preparation and Measurement --- p.15 / Chapter 3.2.2 --- Current-Voltage Measurement (I-V) --- p.17 / Chapter 3.2.3 --- Infrared Transmission Measurements (IR) --- p.19 / Chapter CHAPTER 4 --- RESULTS AND DISCUSSIONS --- p.20 / Chapter 4.1 --- Results of SRP Measurements --- p.20 / Chapter 4.2 --- Results of I-V Measurements --- p.27 / Chapter 4.3 --- Results of IR Measurements --- p.34 / Chapter 4.4 --- Discussions --- p.39 / Chapter 4.4.1 --- IR Absorption Results --- p.39 / Chapter 4.4.2 --- Hot Probe Measurement Results --- p.45 / Chapter 4.4.3 --- SRP Depth Profiles --- p.50 / Chapter 4.4.4 --- Current Transport Mechanism --- p.55 / Chapter 4.4.5 --- Ideality Factor and Transport Mechanisms --- p.76 / Chapter CHAPTER 5 --- CONCLUSIONS AND FUTURE WORKS --- p.85 / Chapter 5.1 --- Conclusions --- p.85 / Chapter 5.2 --- Future Works --- p.86 / APPENDIX --- p.i / BIBLIOGRAPHY --- p.xiii
|
212 |
Réalisation et étude de substrats adaptatifs d'InP utilisant une couche de nanocavités créée par implantation ioniqueChicoine, Martin January 2004 (has links)
No description available.
|
213 |
Anastrozole when used as a superovulator, may alter key focal adhesion proteins associated with receptivity of uterine epithelial cells during implantation in the rat: a potential therapeutic clue in assisted reproductive technologiesMwakikunga, Anthony Raphael. January 2015 (has links)
A thesis submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Doctor of Philosophy
July, 2015 / Introduction: Anastrozole is clinically effective in ovulation induction, but it has not been well researched. The aim of this study was to determine the optimal dose for anastrozole as a superovulator and ascertain its effects on implantation in Wistar rats; also to determine its effects on uterine morphology during early pregnancy using light microscopy and scanning electron microscopy (SEM). [Abbreviated Abstract. Open document to view full version] / AC2016
|
214 |
Spin and charge properties of Si: P probed using ion-implanted nanostructuresMcCamey, Dane Robert, Physics, Faculty of Science, UNSW January 2007 (has links)
This thesis investigates the defects, charge states and spin properties of phosphorus doped silicon, and is motivated by a number of proposals for quantum information processing (QIP) that involve using the spin or charge of individual donors in silicon as qubits. The implantation of phosphorus into silicon is investigated; specifically the ability to remove damage and activate the implanted donors. The impact of implantation on the transport properties of silicon MOSFETs at cryogenic temperatures is used to investigate the damage. Implanting phosphorus into the MOSFET channel leads to reduced electron mobility. The defect density increases linearly with implant density (??ndefect = 0.08 ?? 0.01nimplant). Silicon implantation does not show this effect, suggesting that the additional defects are ionised P donors in the channel. Implant activation for low density donors was complete for an implant density of 2 x 1012 cm2. Similar studies were undertaken on devices with a variety of dielectrics. Thermally grown SiO2 was found to have the lowest defect density of those studied, although Al2O3 deposited via atomic layer deposition was found to have properties that may be useful for the fabrication of devices with low thermal processing budgets. The as-grown defect density of the thermal silicon dioxide was found to be 2.1 ?? 0.3 x 1011 cm2. Ion implantation of nanoscale devices allowed the spin properties of a small number of phosphorus donors in silicon to be probed via electrically detected magnetic resonance. This allowed the detection of the spin resonance of as few as 100 spins. This represents an improvement in number detection of 4 orders of magnitude over previous EDMR studies of donors in silicon. EDMR was used to investigate the properties of P donors in isotopically purified 28Si . The material had a background doping level too high to detect small numbers of spins, however, the narrow linewidth of the phosphorus resonance confirm that the isotopic purity is greater than 0.999. A proof-of-principle demonstration of pulsed EDMR of ion-implanted donors in silicon is presented. The spin dependent transient that results from manipulating the donor spins via pulsed ESR is sensitive to as few as 104 donors, and is a required component for observation of spin Rabi oscillations by this technique.
|
215 |
Restauration de sources radioastronomiques en milieu radioélectrique hostile : Implantation de détecteurs temps réel sur des spectres dynamiques.Dumez-Viou, Cedric 28 September 2007 (has links) (PDF)
L'étude de l'Univers est effectuée de façon quasi-exclusive grâce aux ondes électromagnétiques. La radioastronomie qui étudie la bande radio du spectre est couramment obligée d'observer hors de ses bandes protégées. Il faut donc pouvoir observer des sources dans des bandes où les émissions des systèmes de télécommunication sont souvent proches et donc très puissantes.<br /><br />Les travaux de cette thèse ont eu pour but de développer et d'implanter des méthodes temps réel de traitements numériques visant à atténuer les interférences ambiantes afin de restaurer les radiosources naturelles lors d'observation avec une antenne unique sans informations a priori.<br />Le cœur de ces traitements est basé sur l'estimation de la moyenne d'un échantillon suivant une loi du Khi-2 en présence de points aberrants.<br />Un récepteur numérique multi-instruments à grande dynamique élaboré à la station de radioastronomie de Nançay a servi de banc de test à ces divers algorithmes.<br /><br />La bande corrompue par Iridium est maintenant observable et les sources HI situées dans la bande allouée aux radars sont de nouveau<br />accessibles. Les observations du Soleil et de Jupiter effectuées en<br />bande décamétrique sont maintenant de bien meilleure qualité.<br />Un algorithme a été développé pour configurer le récepteur en tant que détecteur et enregistreur rapide d'évènements très brefs (<100 ms) en milieu parasité. Il est aujourd'hui utilisé pour l'enregistrement de structures fines Joviennes.
|
216 |
Correlations between unexplained infertility and single nucleotide polymorphism in the genes of leukemia inhibitory factor receptor and gp130Malki, Marwa January 2010 (has links)
<p>About 30 % of all infertile couples suffer from infertility of an unexplained cause. Leukemia inhibitory factor (LIF) is a glycoprotein produced by the endometrium and is an important cytokine in the implantation process. LIF exerts its biological functions through heterodimerization of its two receptors: LIF receptor (LIFR) and gp130. Point mutations in the LIF gene have been associated with female infertility. The aim of this study was to investigate whether single nucleotide polymorphisms (SNPs) in the genes of LIFR and gp130 could cause reduced fertility in women. To this end, 115 samples from women diagnosed with unexplained infertility and 191 samples from fertile women were studied. Three SNPs in the gp130 gene and two SNPs in the LIFR gene were analyzed using real-time PCR. One significant difference and a tendency to difference were detected in the gp130 gene for women with unexplained infertility. There were no differences in the LIFR gene variations. In conclusion, polymorphisms in gp130, and thereby disturbances in the LIF pathway, could be one cause for infertility in women diagnosed with unexplained infertility.</p>
|
217 |
Correlations between unexplained infertility and single nucleotide polymorphism in the genes of leukemia inhibitory factor receptor and gp130Malki, Marwa January 2010 (has links)
About 30 % of all infertile couples suffer from infertility of an unexplained cause. Leukemia inhibitory factor (LIF) is a glycoprotein produced by the endometrium and is an important cytokine in the implantation process. LIF exerts its biological functions through heterodimerization of its two receptors: LIF receptor (LIFR) and gp130. Point mutations in the LIF gene have been associated with female infertility. The aim of this study was to investigate whether single nucleotide polymorphisms (SNPs) in the genes of LIFR and gp130 could cause reduced fertility in women. To this end, 115 samples from women diagnosed with unexplained infertility and 191 samples from fertile women were studied. Three SNPs in the gp130 gene and two SNPs in the LIFR gene were analyzed using real-time PCR. One significant difference and a tendency to difference were detected in the gp130 gene for women with unexplained infertility. There were no differences in the LIFR gene variations. In conclusion, polymorphisms in gp130, and thereby disturbances in the LIF pathway, could be one cause for infertility in women diagnosed with unexplained infertility.
|
218 |
Relationship Between Sensorineural Hearing Loss and Vestibular and Balance Function in ChildrenCushing, Sharon Lynn 30 July 2008 (has links)
Similarities between the peripheral auditory and vestibular systems suggest that children with sensorineural hearing loss (SNHL) may demonstrate vestibular and balance impairments. This hypothesis was studied in 40 children with severe to profound SNHL and unilateral cochlear implants (CI). Vestibular function was assessed with caloric, rotational, and vestibular evoked myogenic potential (VEMP) testing; balance was assessed with standardized static and dynamic tests. Horizontal semicircular canal function was abnormal in 53% (17/32) with caloric, and 39% (14/36) with rotational stimulation. Saccular function was absent bilaterally in 5/26 (19%) and unilaterally in 5/26 (19%) with VEMP. Balance abilities were significantly poorer (μ=12.9±5(SD)) than normal hearing controls (μ=17±5(SD); p=0.0006) and correlated best with horizontal canal function from rotational stimulation (p=0.004;R2=0.24). SNHL from meningitis was associated with worse balance function than other etiologies. Vestibular and balance dysfunction occurred in >1/3 of children with SNHL and CI, and is highly dependent on etiology.
|
219 |
Surface Markers and Gene Expression to Characterize the Differentiation of Monolayer Expanded Human Articular ChondrocytesISHIGURO, NAOKI, MITSUYAMA, HIROHITO, ONO, YOHEI, NAKASHIMA, MOTOSHIGE, HIRAIWA, HIDEKI, SAKAI, TADAHIRO, HAMADA, TAKASHI 02 1900 (has links)
No description available.
|
220 |
Relationship Between Sensorineural Hearing Loss and Vestibular and Balance Function in ChildrenCushing, Sharon Lynn 30 July 2008 (has links)
Similarities between the peripheral auditory and vestibular systems suggest that children with sensorineural hearing loss (SNHL) may demonstrate vestibular and balance impairments. This hypothesis was studied in 40 children with severe to profound SNHL and unilateral cochlear implants (CI). Vestibular function was assessed with caloric, rotational, and vestibular evoked myogenic potential (VEMP) testing; balance was assessed with standardized static and dynamic tests. Horizontal semicircular canal function was abnormal in 53% (17/32) with caloric, and 39% (14/36) with rotational stimulation. Saccular function was absent bilaterally in 5/26 (19%) and unilaterally in 5/26 (19%) with VEMP. Balance abilities were significantly poorer (μ=12.9±5(SD)) than normal hearing controls (μ=17±5(SD); p=0.0006) and correlated best with horizontal canal function from rotational stimulation (p=0.004;R2=0.24). SNHL from meningitis was associated with worse balance function than other etiologies. Vestibular and balance dysfunction occurred in >1/3 of children with SNHL and CI, and is highly dependent on etiology.
|
Page generated in 0.2193 seconds