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Targeted imaging with microbubbles may resolve the molecular expression within the abnormal blood vessels of tumours. Optimal imaging requires understanding the interaction between targeted microbubbles and high-frequency ultrasound. Therefore, the subharmonic signal, and backscattering cross-section of individual bound microbubbles were examined with coaligned 30 MHz pulses and optical images. The peak subharmonic signal was generated for 1.6 µm diameter microbubbles for 20% and 11% bandwidth pulses and 1.8 µm for 45% bandwidth pulses at 200 kPa, consistent with estimations of the resonant size of microbubble's at 15 MHz. In order to measure the scattering cross-section, a new method was proposed to measure the receive transfer function of a transducer. Measurements of the backscattering cross-section scaled with the square of the radius, with signi cant size-independent variability. The results of this thesis will help optimise the parameters for targeted imaging, as well as further our understanding of the behaviour of microbubbles.

The purposes of this dissertation were to determine: 1) the relationship betweenmuscle thickness change (MTC) as measured by rehabilitative ultrasound imaging(RUSI) and EMG activity in the lumbar multifidus (LM), 2) if motor control changesproduced by experimentally induced pain are measurable with RUSI, 3) if a differenceexists in MTC between subjects with low back pain (LBP) classified in the treatmentbasedclassification system (TBC) system and controls, 4) if MTC improves followingintervention.Current literature suggests sub-groups of patients with LBP exist and responddifferently to treatment, challenging whether the majority of LBP is "nonspecific". TheTBC system categorizes subjects into one of four categories (stabilization, mobilization,direction specific exercise, or traction). Currently, only stabilization subjects receive anintervention emphasizing stability. Because recent research has demonstrated that motorcontrol impairments of lumbar stabilizing muscles are present in most subjects with LBP,it is hypothesized that impairments may be present across the TBC classifications.Study 1: Established the relationship between MTC as measured by RUSI andEMG in the LM. Study 2: Assessed MTC of the LM during control and painfulconditions to determine if induced pain changes in LM and transverse abdominis (TrA)are measurable with RUSI. Study 3: Measured MTC of the LM and TrA in subjects withLBP classified in the TBC system and 20 controls. Subjects completed a stabilizationprogram and were re-tested.The inter-tester reliability of the RUSI measurements was excellent (ICC3,3 =.91,SEM=3.2%). There was a curvilinear relationship (r = .79) between thickness changeand EMG activity. There was a significant difference (p andlt; .01) between control andpainful conditions on 4 of the 5 LM tasks tested and on the TrA task. There was adifference in MTC between subjects and controls on the loaded LM test which varied bylevel and category. All categories were different from control on the TrA. Followingintervention the TrA MTC improved (p andlt; .01). The LM MTC did not (p values from .13-.86).These findings suggest MTC can be clinically measured and that deficits existwithin TBC system. Significant disability and pain reduction were measured.

The production of gelatine at Gelita N.Z. Ltd. is a time consuming process. The time limiting step in the process is the pre-treatment of the collagen tissue of the raw material in a lime/sodium sulfide solution. The liming solution breaks down the collagen in the tissue to gelatine. This is a necessary step prior to the extraction of gelatine from the hide pieces. The current liming process takes nearly 50 days to complete. Methods were investigated to increase the rate of penetration of the chemicals into the bovine hide raw material. An increase in the penetration of the liming solutions would lead to shorter processing times for this step in the process. The methods that were investigated were temperature controlled mixing, fluidization of the hide pieces and the use of ultrasound. Of all the methods tested, the fluidization of the hide pieces gave the best results. The pretreatment time of the hide pieces was reduced 9 days with this technique. Methods were also investigated to monitor the levels of conditioning in the raw material An accurate technique to measure hide conditioning was important to pilot plant trials. This helped determine how well any of the trail methods increased the penetration of chemicals into the hide pieces. The use of an ultraviolet dye proved an effective method of measuring conditioning for all the pilot plant trials. The level of chemical penetration was monitored by assessing the penetration of the UV dye. The penetration of the UV dye could be quantified by using imaging software. A possible method of monitoring conditioning in full-scale production was tested. It was determined that the glycosaminoglycans and soluble collagen released into the liming solution could be accurately measured, and related to the overall conditioning of the raw material.

The role rehabilitation plays in the management of patients with lateral epicondylalgia (LE) remains elusive secondary to high recurrence rates. Addressing scapular muscle deficits may be important in the rehabilitation of patients with LE. However, it is unknown if scapular muscle impairments exist in a working population of patients with LE. The purpose of this dissertation was to assess scapular muscle strength and endurance in a working population of patients with LE. Clinical scapular muscle assessment tools are limited in their ability to isolate specific muscles. Rehabilitative ultrasound imaging (RUSI) is a potentially useful tool but few studies have investigated its utility. Absolute muscle thickness measurements were obtained on healthy individuals for the lower trapezius (LT) and serratus anterior (SA) under three conditions (arm at rest, arm elevated with a low load, arm elevated with a high load). For both the LT and SA, a significant distinction could be made in muscle thickness between rest and a loaded condition but not between the two load conditions. Furthermore, excellent reliability was demonstrated for both muscles. It is unknown whether arm dominance plays a role in scapular muscle assessments. Therefore, healthy individuals between the ages of 30 and 65 were recruited to compare the effect of arm dominance on scapular muscle strength, endurance, and change in thickness measured by RUSI. Results indicate that arm dominance does significantly affect some measures of scapular muscle strength and endurance. However, the differences between the dominant and non-dominant limbs were not beyond measurement error. Scapular muscle strength, endurance, and change in muscle thickness of the LT and SA were assessed in 28 patients presenting with signs and symptoms consistent with LE. LT strength, SA strength, middle trapezius strength, endurance, and change in SA thickness were significantly less in patients with LE compared to matched controls. SA and LT strength were significantly less in the involved limb compared to the uninvolved limb in patients with LE. The results suggest that assessing scapular muscle endurance as well as LT and SA strength is indicated when evaluating patients with LE, and the results should be compared to normative data.

Three experiments were conducted to explore the effect of fescue toxicosis on vasoconstriction and various parameters of the estrous cycle. In the experiment of Chapter 3, a 2x2 crossover experimental design with repeated measures was implemented to test whether the ingestion of endophyte-infected tall fescue seed would alter blood hormone concentrations of prolactin, progesterone, and estradiol, interovulatory intervals, and corpus luteum blood flow. Also, Doppler ultrasonography was used to assess whether palmar artery and palmar vein lumen diameter, area, circumference, and resistivity index could be altered by the ingestion of endophyte-infected tall fescue seed. Ingestion of endophyte-infected tall fescue seed significantly decreased palmar artery resistivity index, area, and circumference, and palmar artery and palmar vein lumen diameter, but did not alter interovulatory intervals, serum concentrations of prolactin, progesterone, estradiol, or corpus luteum blood flow. Experiments 1 and 2 from Chapter 4 profiled the dopaminergic, serotonergic, and α-adrenergic receptor types and subtypes, as expressed within the equine medial palmar artery, medial palmar vein, and uterine artery transcriptomes. Combined results from Chapters 3 & 4 imply that relative quantity of serotonergic receptor subtypes within a vessel may be related to with the severity of that vessel's vasoconstrictive response to endophyte-infected tall fescue.

Baigiamajame darbe apžvelgiamos organinių medžiagų skaidymo ultragarsu sistemos. Didžiausias dėmesys skiriamas dumblių skaidymo ultragarsu sistemoms. Apžvelgiamos dumblių pritaikymo, jų auginimo ir išgavimo tendencijos. Nagrinėjama išilginių virpesių ultragarsinė dumblių skaidymo sistema „UIP 1000hd”. Darbo tikslas - Standartinio ultragarsinio įrenginio(UIP1000hd Set ) pagalba ištirti botanikos institute auginamų dumblių (augalinių bioląstelių) skaidymo galimybę. Darbo uždaviniai: 1. Įsisavinti naują ultragarsinę įrangą, išmokti naudoti įvairius titaninius koncentratorius, nustatyti reikiamus augalinių bioląstelių skaidymo režimus, išmokti registruoti ultragarsinės sistemos elektrinius ir mechaninius parametrus. 2. Susipažinti su pramoninių dumblių auginimo specifika. Kartu su Botanikos instituto mokslininkais organizuoti tyrimo objekto - dumblių(augalinių bioląstelių) bandomosios partijos užauginimą. 3. Išdirbti dumblių skaidymo lygio vertinimo (tyrimo) metodiką. 4. Išdirbti dumblių skaidymo tyrimo įrenginiu UIP1000hd Set metodiką. 5. Atlikti ultragarsinės sistemos ir kavituojamo skysčio su organine medžiaga virpesių pasiskirstymo analizę ( sistemos kompiuterinis modeliavimas turimomis laboratorijoje programomis). 6. Iš elektrinės ir mechaninės pusės ištirti ultragarsinę sistemą : nustatyti varžines - dažnumines ir amplitudines – dažnumines charakteristikas esant įvairioms elektrin4ms galioms, laisvame ir apkrautame režime. 7. Atlikti 2-3 rūšių pramoninių dumblių... [toliau žr. visą tekstą] / The Master’s Thesis provides an overview on the systems of organic matter decomposition by ultrasound. The focus is on the systems of algal ultrasound decomposition. The tendencies of algae adaptation, cultivation and extraction were reviewed. The ultrasonic algae decomposition system of longitudinal oscillation named “UIP 1000hd” was analyzed. The aims and objectives of the thesis: The aim - is to examine the decomposition possibility of algae (bio cells) growing in the Botanical Institute with the help of standard ultrasound device (UIP1000hd Set). Objectives: 1. To learn about the new ultrasound equipment, learn to use a variety of titanium concentrators, set the required decomposition modes of bio cells, learn to record electrical and mechanical parameters of the ultrasound system. 2. To familiarize with the specifics of industrial algae cultivation. To organize the experimental batch cultivation of the object of the research - algae (plant bio cells) - together with scientists of the Botanical Institute. 3. To master the assessment (research) methodology of the level of algae division. 4. To master the methodology of the algae decomposition equipment UIP1000hd Set. 5. To carry out the distribution of vibration analysis of the ultrasound system and the cativating with the organic matter (the system modeling by computer using programs that are in the Laboratory). 6. To investigate the electrical and mechanical sides of the ultrasound system: to set... [to full text]

The main goal of this thesis is to investigate the nature of an optional consonant deletion process, through an articulatory and acoustic study of word-final consonant clusters in Persian. Persian word-final coronal stops are optionally deleted when they are preceded by obstruents or the homorganic nasal /n/. For example, the final clusters in the words /næft/ “oil”, /suχt/ “burnt” and /qæsd/ “intention” are optionally simplified in fast/casual speech, resulting in: [næf], [suχ], and [qæs]. What is not clear from this traditional description is whether the coronal stop is truly deleted, or if a coronal gesture is produced, but not heard, because it is obscured by the adjacent consonants. According to Articulatory Phonology (Browman & Goldstein 1986, 1988, 1989, 1990a, 1990b, 1992, 2001), the articulatory gestures of the deleted segments can still exist even if the segments are not heard. In this dissertation, ultrasound imaging was used to determine whether coronal consonant deletion in Persian is categorical or gradient, and the acoustic consequences of cluster simplification were investigated through duration and spectral measures. This phonetic study enables an account for the optional nature of the cluster simplification process. A general phonological account is provided for the simplification of coda clusters with rising sonority, and the acoustic and articulatory investigation focuses on the simplification of clusters with coronal stops. Ten Persian-speaking graduate students from the University of Ottawa and Carleton University, five male and five female, aged 25-38 participated in the articulatory and acoustic study. Audio and real time ultrasound video recordings were made while subjects had a guided conversation with a native speaker of Persian. 662 tokens of word-final coronal clusters were auditorily classified into unsimplified and simplified according to whether they contained an audible [t]. Singleton coda consonants and singleton /t/s were also captured as controls. The end of the constriction plateau of C1 and beginning of constriction plateau of C3 were used to define a time interval in which to measure the coronal gesture as the vertical distance between the tongue blade and the palate. Smoothing Splines ANOVA was used in a novel way to compare tongue blade height over time across the three conditions. The articulatory results of this study showed that the gestures of the deleted segments are often still present. More specifically, the findings showed that of the clusters that sounded simplified, some truly had no [t] gesture, some had gestural overlap, and some had reduced gestures. In order to explain the optional nature of the simplification process, it is argued that the simplified tokens are the result of two independent mechanisms. Inevitable mechanical and physiological effects generate gesturally reduced and overlapped tokens whereas planned language-specific behaviors driven by phonological rules or abstract cognitive representations result in no [t]-gesture output. The findings of this study support the main arguments presented in Articulatory Phonology regarding the underlying reasons for sound patterns and sound change. The results of this study are further used to examine different sound change models. It is argued that the simplified tokens with totally deleted [t] gesture could be the result of speakers changing their representations based on other people’s gestural overlap. This would be instances of the Choice and Chance categories in Blevins’ (2004) CCC sound change model. The acoustic results did not find any major cues which could distinguish simplified tokens from controls. It is argued that articulatory data should form an integral part of phonetic studies.

The present study aims to resolve previous disputes about whether or not non-palatalized consonants exhibit secondary velarization in Russian, and if so what this corresponds to articulatorily. Three questions are asked: 1) are Russian non-palatalized consonants velarized or not? If so, 2) what are the articulatory properties of velarization? and 3) how is the presence or absence of secondary velarization affected by adjacent vowels? To answer these questions, laryngeal and lingual ultrasound investigations were conducted on a range of non-palatalized consonants across different vowel contexts. The results of the study show that 1) Russian non-palatalized consonants are not pharyngealized in the sense of Esling (1996, 1999, 2005), 2) /l/ and /f/ are uvularized, 3) /s/ and /ʂ/ can feature either uvularization or velarization. The study also shows that secondary articulations of Russian non-palatalized consonants are inherent rather than dependent on vowel context. / Graduate / 0290 / natallia@uvic.ca