This study examined the effects of plyometrics on running economy, performance, and Achilles tendon properties in female distance runners. Seventeen University athletes matched by running economy were randomly assigned to an experimental group that received supplementary plyometrics training (n=9) or a control group that performed run-training only (n=8). Subject attrition led to a final sample of twelve runners (6 experimental, 6 controls). Measurements were made pre-post an 8-week training period. Running economy was measured as oxygen consumption at three submaximal speeds, performance as time to run 3000 meters, and Achilles tendon properties were estimated via ultrasound during ramp, quasi-isometric plantar flexion to maximum on an isokinetic dynamometer. No significant differences were found between the two groups after eight weeks because of poor subject compliance and excessive variability in ultrasound measurements. The results are inconclusive as to the effect of supplementary plyometric training on running economy, performance and Achilles tendon properties.

Gegenstand und Ziel: Einsatz des Ultraschallkontrastmittels SonoVue® zur Ermittlung der Hepatischen Transitzeit bei lebergesunden Hunden. Material und Methoden: Untersucht wurden 45 lebergesunde Hunde aus dem Patientengut der Klinik für Kleintiere der Universität Leipzig. Ausschlusskriterien waren Leber- und Herz-Kreislauferkrankungen, sowie Tumorleiden. Die Kontrastmitteluntersuchungen erfolgten am narkotisierten Tier. Das Kontrastmittel wurde intravenös appliziert. Die Zeitdifferenz zwischen Ankunft in den Leberarterien bis zum Erreichen der Lebervenen wird als Hepatische Transitzeit definiert. Die Auswertung erfolgte von zwei unabhängigen Betracht-ern, sowie einer im Ultraschallgerät installierten Analysesoftware (TIC; Time-intensity-curve). Erfasst wurden zusätzlich von jedem Patienten die Blutflussgeschwindigkeiten in der Aorta abdominalis und den Lebervenen vor und nach der Kontrastmitteluntersuchung. Ebenfalls sind die Ankunftszeiten des Kontrastmittels in den Leberarterien und Lebervenen ermittelt worden. Diese Daten wurden mit den Angaben des Alters, dem Geschlecht und dem Gewicht verglichen. Die ermittelten Ankunftszeiten des Kontrastmittels wurden mit den Blutflussgeschwindigkeiten des jeweiligen Patienten korreliert. Ergebnisse: Die Hepatische Transitzeit des Kontrastmittels SonoVue® für lebergesunde Hunde beträgt 9,82 s. Schlussfolgerungen: Die Hepatische Transitzeit des Signalverstärkers SonoVue® beim lebergesunden Hund liegt bei 9,82 s und ist damit ca. eine Sekunde kürzer als beim Men-schen. In anschließenden Studien muss bei Hunden mit nachgewiesenen Lebermetastasen die Hepatische Transitzeit ermittelt werden. Entsprechen die Ergebnisse denen aus der Human-medizin, so ist mit einer Verkürzung der Hepatischen Transitzeit zu rechnen. Insbesondere bei bekanten Primärtumor könnte mit dieser Methode eine Metastasierung früher erkannt werden.

Following Carslaw [1] and as discussed by Becker et al [2], the diffusion of ultrasonic energy in cement-based aggregates follow the heat diffusion equation. However, due to the finite size of the discs used in experiments by Becker, ultrasound energy is contained within the body for a longer period of time, as compared to [2]. Though the energy content of the disc in reality would eventually decay to zero, due to leaks and other mechanisms, a theoretical study of perfectly adiabatic case is useful to compare the residual energy values to material properties. As a particular example, the input energy sees multiple phenomena inside the material during propagation. The residual energy is this a combined effect of the multiple scattering, dissipative and diffusive processes. This objective of this thesis is to study the relationship between the residual spectral density and specimen geometry. The effort further aims to attribute the difference in the residual spectral energy density values in materials of similar geometry to the varying material properties of the heterogeneous materials. Finally, a study of the error propagation in the estimation is presented, along-with an analytical relationship showing the value of spectral energy density for discs of finite radius and height. Ref: 1. H. S. Carslaw, J.C.J., Conduction of Heat in Solids. 2nd ed ed. 1986: Oxford University Press, USA. 520 2. Becker, J., L.J. Jacobs, and J. Qu, Characterization of cement-based materials using diffuse ultrasound. Journal of Engineering Mechanics, 2003. 129(12): p. 1478-1484.

Consumer demands are driving the current trend in the microelectronics industry to make electronic products that are miniature, fast, compact, high-density, reliable and low-cost. The use of surface mount devices (SMDs) has helped to decrease the size of electronic packages through the use of solder bump interconnections between the devices and the substrates/printed wiring boards (PWBs). Solder bumps act as not only mechanical, but also electrical interconnections between the device and the substrate/PWB. Common manufacturing defects ¨C such as open, cracked, missing, and misaligned solder bumps ¨C are difficult to detect because solder bumps are hidden between the device and the substrate/PWB after assembly. The reliability of packaged electronic devices in storage and usage is a major concern in the microelectronics industry. Therefore, quality inspection of solder bumps has become a critical process in the microelectronics industry to help ensure product quality and reliability. In this thesis, a methodology for quality evaluation and reliability study of solder bumps in electronic packages has been developed using the non-destructive and non-contact laser ultrasound-interferometric technique, finite element and statistical methods in this research work. This methodology includes the following aspects: 1) inspection pattern ¨C specific inspection patterns are created according to inspection purpose and package formats, 2) laser pulse energy density calibration ¨C specific laser pulse power and excitation laser spot size are selected in terms of package formats, 3) processing and analysis methods, including integrated analytical, finite element and experimental modal analyses approach, advanced signal processing methods and statistical analysis method, 4) approach combining modal analysis and advanced signal processing to improve measurement sensitivity of laser ultrasound-interferometric inspection technique, and 5) calibration curve using energy based simulation method and laser ultrasound inspection technique to predict thermomechanical reliability of solder bumps in electronic packages. Because of the successful completion of the research objectives, the system has been used to evaluate a broad range of solder bump defects in a variety of packaged electronic devices. The development of this system will help tremendously to improve the quality and reliability of electronic packages.

Ultrasound has been identified as a possible non-invasive drug delivery device that could avoid many of the problems found in traditional therapeutics. Studies have shown that ultrasound can deliver molecules into cells; however, the applicability of ultrasound has been limited due to uncontrollable cellular viability losses after sonication. In this study, we sought to quantify the heterogeneous bioeffects of ultrasound in order to gain more insight into how ultrasound affects cells. We were also concerned with identifying the causes of and preventing programmed cell death caused by ultrasound exposure. In order to accomplish these objectives, we used flow cytometry to group cells into quantifiable characteristic populations. This allowed us to identify the relative importance of different forms of rapid cell death. We found that up to 65% of cells (at the highest ultrasound pressure studied) can lose viability rapidly and, for the first time, quantified them among three distinct populations: (1) cells that retain normal size but lose plasma membrane integrity; (2) intact nuclei surrounded by plasma membrane remnants; (3) debris resulting from cellular lysis. Our analysis was supported by mechanical sorting of these populations and subsequent imaging using confocal microscopy. We then monitored the viable populations for 6 h after ultrasound exposure. Results indicated that up to 15% of viable cells (at the highest ultrasound pressure studied) underwent apoptosis, which we showed was associated with an influx of intracellular Ca2+; therefore, we developed a method of chelating intracellular Ca2+ after sonication in an effort to maintain viability of those cells. Using this technique, we showed for the first time that cells could be saved, and we were able to prevent apoptosis by 50%, thereby increasing the overall viability of cells exposed to ultrasound. We conclude that ultrasound is a useful method to deliver molecules into cells and that appropriate selection of sonication conditions can minimize cell death by rapid and apoptotic mechanisms.

First degree relatives (FDRs) of subjects with early onset of coronary heart disease (CHD) have higher risk of developing cardiovascular disease. We verified early CHD by angiography in the index patients and extensively phenotyped their FDRs to investigate the relationship of traditional and non-traditional cardiovascular risk factors to carotid ultrasound and coronary calcium scoring findings. B-mode carotid ultrasound was used to assess the combined intima-media thickness and plaque burden in 111 FDRs. The biochemical and anthropometrical characteristics of the FDRs were compared with those of healthy controls matched for sex, age, ethnicity and BMI. Odds ratios indicate that FDRs are more likely to have positive carotid ultrasound findings compared to controls; 2.23 (95% CI 1.14 – 4.37) for intima-media thickness and 2.3 (95% CI 1.22 - 4.35) for average total thickness. In multivariate analysis positive carotid ultrasound findings were higher in FDRs independent of age, gender, total cholesterol over HDL-c ratio, systolic blood pressure and smoking but not homocysteine which had higher values in FDRs compared to controls. In conclusion FDRs of patients with angiographically confirmed CHD have higher burden of subclinical atherosclerosis even when considered in the context of traditional risk factors. Coronary artery calcium scoring (CAC), assessed by 64-slice multi-detector computed tomography (MDCT), was used to assess burden of subclinical atherosclerosis in 57 FDRs compared to controls. FDRs have a two-fold increase in risk of having CAC positive findings; odds ratios for the 75th percentile was 1.96 (95%CI 1.04 – 3.67, p<0.05) while for the 90th percentile odds ratio was 2.59 (95% 1.232 – 5.473, p<0.05). In summary, the risk of significant CAC findings, measured by 64-slice MDCT, is two-fold higher in FDRs than controls. These findings correlate highly with carotid ultrasound findings in the same cohort. Different thresholds for CAC may be appropriate when assessing male versus female FDRs. Together increased carotid ultrasound findings and CAC scoring results in FDRs of patients with validated early onset of CHD suggest these imaging techniques as potentially useful tools in cardiovascular risk assessment that will go above and beyond the current diagnostic algorithms.

A system for vessel characterization aimed at detecting deep vein thrombosis (DVT) in the lower limbs has been developed and evaluated using ultrasound image processing, location and force sensors measurements, blood flow information and a protocol based on the current clinical standard, compression ultrasound. The goal is to provide an objective and repeatable system to measure DVT in a rapid and standardized manner, as this has been suggested in the literature as an approach to improve overall detection of the disease. The system uses a spatial Kalman filter-based algorithm with an elliptical model in the measurement equation to detect vessel contours in transverse ultrasound images and estimate ellipse parameters, and temporal constant velocity Kalman filters for tracking vessel location in real-time. The vessel characterization also comprises building a 3-D vessel model and performing compression and blood flow assessments to calculate measures that indicate the possibility of DVT in a vessel. A user interface designed for assessing a vessel for DVT was also developed. The system and components were implemented and tested in simulations, laboratory settings, and clinical settings. Contour detection results are good, with mean and rms errors ranging from 1.47-3.64 and 3.69-9.67 pixels, respectively, in simulated and patient images, and parameter estimation errors of 5%. Experiments showed errors of 3-5 pixels for the tracking approaches. The measures for DVT were evaluated, independently and integrated in the system. The complete system was evaluated, with sensitivity of 67-100% and specificity of 50-89.5%. System learnability and memorability were evaluated in a separate user study, with good results. Contributions include a segmentation approach using a full parameter ellipse model in an extended Kalman filter, incorporating multiple measurements, an alternate sampling method for faster parameter convergence and application-specific initialization, and a tracking approach that includes a sub-sampled sum of absolutes similarity calculation and a method to detect vessel bifurcations using flow data. Further contributions include an integrated system for DVT detection that can combine ultrasound B-mode, colour flow and elastography images for vessel characterization, a system interface design focusing on usability that was evaluated with medical professionals, and system evaluations through multiple patient studies.

The dissolution of quantum sized CdS and MnO2 particles in water was conducted using 20 kHz ultrasound. CdS particles were found to dissolve chemically via an oxidation process while MnO2 particles dissolved via a reductive process. It was found that the dissolution of the colloids could be controlled via the addition of surface active chemicals to solution and by varying the saturation gas type. In the presence of Na2S or propan-2-ol and argon gas, the dissolution of CdS was inhibited, whereas the addition of alcohols (methanol, ethanol, propan-2-ol, butan-1-ol and pentan-1-ol) to the MnO2 system led to an increase in the amount of dissolution for a given time of sonication. This increase in dissolution was found to be dependent on the ability of the surface active radical scavenger to accumulate around the bubble interface during the cavitation process. Eventually, at higher alcohol concentration there was a plateau or a limiting value reached for the efficiency of colloid dissolution which was common for each alcohol. (For complete abstract open document)

Thesis(M.S.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.

Diss. (sammanfattning) Göteborg : Göteborgs universitet, 2007. / Härtill 5 uppsatser.