Two issues hindering the clinical application of image-guided transcostal focused ultrasound surgery (FUS) are the organ motion caused by cardiac and respiratory movements and the presence of the ribcage. Intervening ribs absorb and reflect the majority of ultrasound energy excited by an acoustic source, resulting in insufficient energy delivered to the target organs of the liver, kidney, and pancreas. Localized hot spots also exist at the interfaces between the ribs and soft tissue and in highly absorptive regions such as the skin. The aim of this study is to assess the effects of transmitted beam distortion and frequency-dependent rib heating during trans-costal FUS, and to propose potential solutions to reduce the side effects of rib heating and increase ultrasound efficacy. Direct measurements of the transmitted beam propagation were performed on a porcine rib cage phantom, an epoxy rib cage phantom and an acoustic absorber rib cage phantom, in order of their similarities to the human rib cage. Finite element analysis was used to investigate the rib cage geometry, the position of the target tissue relative to the rib cage, and the geometry and operating frequency of the transducer. Of particular importance, frequency-dependent heating at the target and the intervening ribs were estimated along with experimental verification. The ratio of ultrasonic power density at the target and the ribs, the time-varying spatial distribution of temperature, and the ablated focus of each sonication are regarded as key indicators to determine the optimal frequency. Following that, geometric rib-sparing was evaluated by investigating the operation of 2D matrix arrays to optimize focused beam shape and intensity at target. Trans-costal FUS is most useful in treating tumours that are small and near the surface of the abdominal organs, such as the liver, kidney and pancreas. However, for targets deep inside these organs, severe attenuation of acoustic energy occurs, suggesting that pure ultrasound thermal ablation with different heating patterns will have limited effects in improving the treatment efficacy. Results also demonstrate that the optimal ultrasound frequency is around 0.8 MHz for the configurations considered, but that it may shift to higher frequencies with changes in the axial and lateral positions of the tumours. In this work, I aimed to reduce the side effects of rib heating and increase the ultrasound efficacy at the focal point in trans-costal treatment. However, potential advanced techniques need to be explored for further enhanced localized heating in trans-costal FUS.

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Tip Enhanced Near-field Optical Microscopy (TENOM) is a method for optically imaging at resolutions far below the diffraction limit. This technique requires optical nano-probes with very specialized geometries, in order to obtain large, localized enhancements of the electromagnetic field, which is the driver behind this imaging method. Traditional methods for the fabrication of these nano-probes involve electrochemical etching and subsequent FIB milling. However, this milling process is non-trivial, requiring multiple cuts on each probe. This requires multiple rotations of the probe within the FIB system, which may not be possible in all systems, meaning the sample must be removed from vacuum, rotated by hand and placed back under vacuum. This is time consuming and costly and presents a problem with reproducibility. The method presented here is to replace multiple cuts from a side profile with a small number of cuts from a top down profile. This method uses the inherent imaging characteristics of the FIB, by assigning beam dwell times to specific locations on the sample, through the use of bitmap images. These bitmaps are placed over the sample while imaging and provide a lookup table for the beam while milling. These images are grayscale with the color of each pixel representing the dwell time at that pixel. This technique, combined with grayscale gradients, can provide probes with a symmetric geometry, making the system polarization independent.

acase@tulane.edu / Introduction: High-Intensity Focused Ultrasound (HIFU) is the only noninvasive method available today for thermal ablation of tumors. HIFU-induced rapid heating and mechanical disruption of tissue, not only has a direct destructive effect on tumors, but also provides a noninvasive way for targeted release of chemotherapeutic drugs from drug delivery vehicles such as temperature sensitive liposomes (SfTSLs). The objective of this work was to evaluate the synergistic treatment of Sorafenib-loaded TSLs (SfTSLs) and HIFU via in vitro analysis of cell viability and proliferation using an aggressive human liver cancer cell line and corresponding in vivo analysis of tumor growth and survival using a human xenograft mouse model. Materials and Methods: Liposomes were developed using 70% Dipalmitoylphosphatidylcholine, 20% L-a-Phosphatidylcholinehydrogenated Soy, and 10% Cholesterol using thin film hydration method to encapsulate Sorafenib at 10μM. Pellets of Hep3B human liver cancer cells (100 μl, 2.7 million cells/ml) were placed in a 0.2 ml thin-wall PCR tube to mimic dense tumor aggregation. Cell pellets were then inoculated with HIFU alone, SfTSLs, or exposed to a combination of HIFU and SfTSLs. The focused ultrasound signal was generated by a 1.1 MHz transducer with acoustic power ranging from 4.1 W to 12.0 W. Cell viability and proliferation experiments were conducted to measure cancer cell damage at 24, 48, 72, and 96 h post treatment via Annexin V/PI and WST-8 staining. In our in vivo study, 1.0×106 Hep3B cells in Matrigel were injected into left and right flanks of athymic nude mice. Tumors were allowed to grow to 8-10 mm size and then separated into the following treatment groups: HIFU alone, SfTSLs (50 μl) alone, SfTSLs + HIFU, and sham. Tumor sizes were measured by caliper every day and a diagnostic ultrasound system was used pre-treatment, 5 days, 14 days, and prior to sacrificing. Tumors were grouped and processed at 5 days, 14 days, or placed in a survival study to evaluate whether treatment facilitated longer lifespans. Tumor tissues were collected for H&E staining and evaluated by a blinded pathologist post euthanasia. Results and Discussion: Our in vitro data indicate that Hep3B cells exposed to both SfTSLs and HIFU have a significantly lower viability and proliferation rate than untreated cells or the cells treated with only SfTSLs or HIFU. According to our in vivo study, tumor growth in the SfTSLs + HIFU group was reduced as compared to Sham, SfTSLs only, or HIFU only groups. Conclusions: The results of our in vitro and in vivo experiments clearly indicate that chemotherapeutic drug-loaded SfTSLs and HIFU can be an effective therapy for locally aggressive liver cancer. This combination treatment leads to more cellular damage, reduction in tumor growth, and better survival. / 1 / Gray Halliburton

<p>In this thesis, we aim to find out ways that Multimind’s create customer focused value and sustain the value in the recruitment industry and their customer relationship management in the niche market. Our purpose is also to study their strategy, policies and their organizational culture especially in customer focused value and relationship management in this service business.  In this thesis we will study only on their strategy toward this niche market. Therefore, the scope of study will cover its business’s history on company’s objective, operation process, organization’s culture, company’s policy and strategy in market learning and innovation. We use qualitative method by conducting the interview with the informant. We use both primary and secondary data for collecting the data. In our primary data, judgment sampling method is being applied in selecting the interviewee. For Secondary data; we have searched the information from the company’s website, academic journals from university library. </p>

High Intensity Focused Ultrasound (HIFU) is a promising technique for the treatment of localized cancers. The ability to focus ultrasound precisely on a predetermined volume allows the possibility of selective tissue destruction at this position without damage to surrounding tissues. However, many difficulties remain in the treatment of deep-seated tumors. In this thesis, new therapeutic and monitoring techniques are proposed to address these problems, by using phased arrays of ultrasound transducers. Two monitoring techniques based on the detection of the displacements of the ultrasonic speckle are developed, and allowed us to image the changes in the temperature and the shear modulus during HIFU therapy. In-vitro ultrasound-guided experiments are performed. Secondly, the problem of organs motion during the treatment is addressed. A method for real-time tracking the 3D motion of tissues is combined with a 2D High Intensity Focused Ultrasound multi-channel system in order to correct the respiratory motion during HIFU therapies. In the last section of this thesis, a high power ultrasonic system is developed for transcranial HIFU brain therapy. The skulls aberrations are corrected using a time reversal mirror thanks to an implanted hydrophone. In-vivo experiments are conducted on 22 sheep with minimally invasive surgery. Finally, a non-invasive protocol based on CT scans of the entire skull is developed and allows the prediction of the skulls aberrations and the skull overheating.

The glancing angle deposition (GLAD) technique is now used by over one hundred research groups, each requiring a fundamental understanding of and new techniques for modulating the properties of GLAD in order to optimize their results. In this thesis, the structural characteristics of nanostructured columnar films were therefore investigated and quantified using gas adsorption porosimetry, focused ion beam tomography, optical methods, scanning electron microscopy (SEM) image analysis. Questions such as ``What is their surface area?'', ``How porous are they?'', ``How do the films evolve as they grow?'', and ``Can the structural characteristics be manipulated?'' were answered. Surface areas, determined from krypton gas adsorption, were found to be high, making GLAD promising for applications requiring large and rough surface interfaces. Specifically, peak specific surface areas of 700 +/- 150 m^2g^{-1}, 325 +/- 40 m^2g^{-1}, 50 +/- 6 m^2g^{-1} were measured for silica (SiO_2), titania (TiO_2) and indium tin oxide (ITO), respectively. Broad pore distributions, with peaks in the low mesoporous regime of 2 nm to 5 nm, were also determined. The internal surface area may also be up to three times as high as that of the externally exposed surface. As well, despite the fact that GLAD column broaden as they grow, the surface area increases linearly with film thickness. Focused ion beam milling, with concurrent SEM imaging, was then employed to investigate and reconstruct the three-dimensional structure of GLAD films in the tens of nanometers regime not measurable by krypton gas adsorption porosimetry. The measured growth scaling trends agreed with previous findings, but were determined using only one sample, instead of multiple samples of increasing thickness. Mean column diameters, center-to-center spacings, void spacings, and column densities were found to scale with thickness as w = (9.4 +/- 3.0) t^{0.35 +/- 0.09} nm, c = (24.8 +/- 5.2) t^{0.31 +/- 0.08} nm, v = (15.2 +/- 3.8) t^{0.25 +/- 0.06} nm, and d = (3400 +/- 2500) t^{-0.65 +/- 0.15} columns um^{-2}, respectively. Finally, spatially graded nanostructures were demonstrated by extending the GLAD technique to include macroscopic shadowing. Optically transparent, graded thickness and pitch helical films were fabricated with polarization selectivity over a spatial range of 30 mm, concurrent with 70 nm spectral tunability. These structures will be useful for tunable frequency photonic devices. / Micro-Electrical-Mechanical Systems (MEMS) and Nanosystems

The fabrication characteristic of etching and deposition of focused ion beam (FIB) on the submicron structure of silica and quartz glass was investigated. FIB has several advantages such as high sensitivity, high material removal rate, and direct fabrication in some selected areas without the use of etching mask, etc. In this study, silicon and quartz glass materials etched by FIB were used for fast fabrication of 3-D submicron structures to investigate the differences between the samples before and after fabrication. The expansion effect of silicon with sputtered platinum on surface is compared with Pyrex glass with sputtered chromium on surface. The result shows the side wall of structure in the center wouldn¡¦t be vertical after etching and trimming on the quartz glass and the silicon substrate. Trenches with different depth and width on the surface of silicon were etched by FIB and measured by Atomic Force Microscope. Lines with different interval were deposited by FIB on the surface of quartz glass and were measured by Atomic Force Microscope.

In this thesis, we aim to find out ways that Multimind’s create customer focused value and sustain the value in the recruitment industry and their customer relationship management in the niche market. Our purpose is also to study their strategy, policies and their organizational culture especially in customer focused value and relationship management in this service business.  In this thesis we will study only on their strategy toward this niche market. Therefore, the scope of study will cover its business’s history on company’s objective, operation process, organization’s culture, company’s policy and strategy in market learning and innovation. We use qualitative method by conducting the interview with the informant. We use both primary and secondary data for collecting the data. In our primary data, judgment sampling method is being applied in selecting the interviewee. For Secondary data; we have searched the information from the company’s website, academic journals from university library.