Nanoparticle Mediated Heating for Non-invasive Thermal Therapies A

PhDNanomaterials have unique physics and chemistry properties compared with their bulk counterparts and have been widely studied in different fields ranging from energy to biomedicines. This thesis investigates controlled synthesis of gold nanomaterials, the heating and interactions of gold nanomaterials with external electromagnetic and ultrasonic fields, and their potential applications in non-invasive heat-related biomedicines. Gold nanomaterials have been synthesised by the citrate reduction method with the aid of ultrasonification. Through ultrasonification, the size of obtained spherical GNPs can be controlled between 10nm and 15nm, and the prepared nanoplates can be controlled between 50 nm to 150 nm. Purification process has been performed through membrane dialysis, in order to obtain pure nanoparticles for investigating the heating behavior of nanoparticle dispersions under EM/ultrasound field and elucidating the impurity effect. Moreover, the purified gold nanoparticles have been characterized by various means, such as FTIR, atomic absorption spectrometer, zetasizer, SEM, TEM and UV-Vis absorption for the purpose of fully understand the properties of gold nanoparticle in terms of purity, concentration, size, morphology and optical properties. The bulk heating effects of low-concentration GNPs have been investigated by using ultrasonic field, electromagnetic (EM) field, and laser irradiation. The results have shown that significant bulk temperature increase can be achieved for the lowconcentration gold nanoparticle dispersions under ultrasonic field, the EM field at 200 kHz and 400 kHz, and laser irradiation. Comparatively, the purified GNPs did not show significant heating effect under the EM fields of 13.56 MHz and 2.45 GHz. 6 Different mechanisms are thereby discussed to explain the heating effects. While some can be explained by established theories, such as the ultrasonic and laser heating, it is still unclear about the heating effect under low frequency EM field. A few possible reasons could be attributed to the changes of the dielectric properties and the electrophoresis effect. In addition, GNP incorporated microcapsules have been fabricated through the layer-bylayer technology, and laser treatments of the microcapsules embedded with different shapes of gold particles have been studied. The results have shown that matching between the laser wavelength and the absorption band of gold nanoparticles, which can be shifted by controlling the morphology of nanoparticles, is a prerequisite to achieve the maximum heating effect to deform the microcapsules and hence to present the microcapsules for biomedical uses. In vitro (B50 cell) and in vivo (fruit fly) studies of the biocompatibilities of our synthesised GNPs have been exanimated. The results demonstrated that the GNPs have high biocompatibility for B50 cells and fruit flies. GNPs assisted laser treatment of B50 cells has shown faster thermal damage to the cells in contrast to the cells without addition of GNPs. Keywords: nanomaterial, gold nanoparticle, capsules, hyperthermia, ablation, electromagnetic, ultraosound, surface Plasmon resonance, biocompatibility

Triangle trade relation among China, the EU and Taiwan under the aspect of the WTO

The book fits into a multidisciplinary research approach. The articles are the result of research conducted by eminent international economists, authors representing academic centres in different countries. The articles address current phenomena observed in the global economy. The authors do not aspire to comprehensively explain all the very complex and multi-dimensional economic developments, but illustrate many of these phenomena in an original way. The multi-threaded and multi-dimensional nature of the discussion in particular articles deserves attention. These include theoretical and methodological articles as well as the results of empirical research presented by the authors. The book is addressed to those persons interested in issues of economics, finance, regional economy, and the management sciences. It can be valuable for economic practitioners, members of management and supervisory boards of companies, and financial analysts, and the articles may also be useful for academicians and students.The WTO is a member-driven international trade organization composed of governments and customs territories. It sets the legal framework for trade among the members. The EU as successor of the EC is the founding member since the establishment of the WTO in 1995. With the gradual enlargement process, the EU has been also one of the super members with the strong economic power within the WTO. Since the open and reform towards the world economy, China has taken a rapid step for the economic development in the 1980s. China has accessed into the WTO in Dec. 2001. The Taiwan’s economy strongly depends on export. Therefore, trade plays a very important role for Taiwan. Taiwan has become the 144th member of the WTO since 2002. Nowadays the WTO is an important platform for Taiwan in the international community, especially the Cross-Straits trade relation between China and Taiwan. With the trend of globalization, the trade relation between China and Taiwan is unavoidable and inevitable. The Cross-Straits trade relation has rapidly developed after their access into the WTO. As a result, the WTO has become an important platform for the interaction between China and Taiwan. Furthermore, China and Taiwan have concluded in 2009 the Economic Cooperation Framework Agreement (ECFA) under the WTO. This thesis firstly works on the ECFA as basis to explain its content and its impact on the both-side development. Secondly, it deals with the triangle relation among China, the EU and Taiwan within the WTO. Furthermore, it focuses on the signification of the ECFA for the triangle trade relation and its future. Finally, it draws a conclusion as finding of this research

A case-control study of occupational magnetic field exposure and Alzheimer's disease: results from the California Alzheimer's Disease Diagnosis and Treatment Centers

BACKGROUND: A few studies have investigated a possible relationship between Alzheimer's disease (AD) and occupations with extremely low frequency magnetic field (MF) exposure. The purpose of this study was to further evaluate this possible association in a large patient population with expert diagnoses. METHODS: Subjects came from the 8 of the 9 California Alzheimer's Disease Diagnostic and Treatment Centers not previously used in an earlier study. Cases had probable or definite AD; controls primarily had a dementia-related problem other than vascular dementia (VaD) and some were not demented upon expert examination. Occupations were classified as having low, medium or high MF exposure, based upon previous research, replicating the exposure methodology used in our previous published studies. RESULTS: Occupational information was available for 98.6% of the 1527 cases and 98.5% of the 404 controls with age-at-initial examination known to be at least 65. Among cases, 2.1% and 5.4% had high and medium occupational MF exposure, respectively, while among controls the percentages were 0.8% and 3.0%. In univariate analyses, the odds ratio (OR) for subjects with medium or high MF exposures combined was 2.1 (p < 0.01), while for high exposure alone the OR was 2.9 (p < 0.08). Two models were used in multivariate analyses, with gender, stroke, and either age-at-onset or age-at-initial examination as covariates. The ORs for MF exposure varied little between the two models: 2.2 (p < 0.02) and 1.9 (p < 0.03) for medium or high exposure; 2.7 (p < 0.11) and 3.2 (p < 0.12) for high exposure. OR estimates for females were higher than for males, but not significantly higher. There were no material differences between the ORs resulting from univariate and multivariate analyses. CONCLUSION: Elevated occupational MF exposure was associated with an increased risk of AD. Based on previous published studies, the results likely pertain to the general population

Enhancement of polar phases in PVDF by forming PVDF/SiC nanowire composite

Different contents of silicon carbide (SiC) nanowires were mixed with Poly(vinylidene fluoride) (PVDF) to facilitate the polar phase crystallization. It was shown that the annealing temperature and SiC content affected on the phase and crystalline structures of PVDF/SiC samples. Furthermore, the addition of SiC nanowire enhanced the transformation of non-polar α phase to polar phases and increased the relative fraction of β phase in PVDF. Due to the nucleating agent mechanism of SiC nanowires, the ion-dipole interaction between the negatively charged surface of SiC nanowires and the positive CH2 groups in PVDF facilitated the formation of polar phases in PVDF

RNA interference of argininosuccinate synthetase restores sensitivity to recombinant arginine deiminase (rADI) in resistant cancer cells

Background Sensitivity of cancer cells to recombinant arginine deiminase (rADI) depends on expression of argininosuccinate synthetase (AS), a rate- limiting enzyme in synthesis of arginine from citrulline. To understand the efficiency of RNA interfering of AS in sensitizing the resistant cancer cells to rADI, the down regulation of AS transiently and permanently were performed in vitro, respectively. Methods We studied the use of down-regulation of this enzyme by RNA interference in three human cancer cell lines (A375, HeLa, and MCF-7) as a way to restore sensitivity to rADI in resistant cells. The expression of AS at levels of mRNA and protein was determined to understand the effect of RNA interference. Cell viability, cell cycle, and possible mechanism of the restore sensitivity of AS RNA interference in rADI treated cancer cells were evaluated. Results AS DNA was present in all cancer cell lines studied, however, the expression of this enzyme at the mRNA and protein level was different. In two rADI-resistant cell lines, one with endogenous AS expression (MCF-7 cells) and one with induced AS expression (HeLa cells), AS small interference RNA (siRNA) inhibited 37-46% of the expression of AS in MCF- 7 cells. ASsiRNA did not affect cell viability in MCF-7 which may be due to the certain amount of residual AS protein. In contrast, ASsiRNA down- regulated almost all AS expression in HeLa cells and caused cell death after rADI treatment. Permanently down-regulated AS expression by short hairpin RNA (shRNA) made MCF-7 cells become sensitive to rADI via the inhibition of 4E-BP1-regulated mTOR signaling pathway. Conclusions Our results demonstrate that rADI-resistance can be altered via AS RNA interference. Although transient enzyme down- regulation (siRNA) did not affect cell viability in MCF-7 cells, permanent down- regulation (shRNA) overcame the problem of rADI-resistance due to the more efficiency in AS silencing