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Protein Variation of Paramecium in Ultrasonic FieldChiu, Wen-Kuei 10 February 2004 (has links)
The problem of the long-term proliferation of cells is a seminal one. It has always been a hot subject in biology. In this reach, it try to improve the growth rate of paramecium by ultrasound exposure. To perform the above-mentioned research, the oscillation of the paramecium in response to the ultrasound radiation is simulated using Rayleigh-Plesset¡¦s bubble activation theory. The gas body activation theory is to calculate the resonant frequencies of the paramecium at different stages of its life.
In this research, it will study the activation of the paramecium division using the resonant and non-resonant frequency of the ultrasonic exposure. The observing images obtained from a microscopic camera can be made and recorded by a personal computer. The biological effects such as the hatching period, growth rate, etc., can be observed from the images. In the past, the physical measurement such as the counting method is the easiest way to observe the biological effects of ultrasound. However, it is not sufficiently to analyze the quantitative bioeffect of paramecium by taking counts. Therefore, utilizing the biochemical technique to assay the difference of specimen may be a good point of view. In this research, employing BCA (Bicinchoninic Acid) assay to inspect the protein variation attain a brand-new quantitative analysis. The results obtained from this research can be used to develop the related ultrasonic biotechnology.
By using the theory, the calculated resonance frequency of the paramecium vacuole is about 0.467~1.27 MHz. The maximum amount of paramecium was observed in 72th hours with 1 MHz ultrasound exposure for 5 minutes. It¡¦s 1.77 times relative to the control.
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The Mechanism Study of the Sonophoresis to the Permeation of Stratum CorneumHuang, Chong-ren 14 February 2005 (has links)
The study of the bioeffects of ultrasound and their etiology is of fundamental importance as a part of basic biophysics. In general, the most fruitful approach to the study of bioeffects of physical agents is the mechanistic one. The ultrasonic mechanisms include the mechanical effect, convective effect, cavitation effect, and thermal effect. In this research, the test skin was radiated the ultrasound using the medical equipment and analyzed the permeation of skin. However, it is not sufficiently to analyze the quantitative of the sonophoresis by the medical equipment setup.
To solve the above-mentioned problem, the oscillation of the stratum corneum in response to the ultrasound radiation is simulated using Rayleigh-Plesset¡¦s bubble activation theory. To calculate the resonance frequency domain of bubbles attached of pig skin which is around 15 to 36 kHz that called low frequency and it caused gas body activation on test skin. We choose 20 kHz in the resonance frequency domain to compared with 10, 60 kHz as non-resonance frequency. 1.9 and 13.6 mW/cm2 of the sound intensity which are respectively lower and higher than cavitation threshold intensity are used. The result of low frequency sonophoresis presented that high permeation rate is caused by resonance frequency 20 kHz. And according to the experiment, it is also proved that the experiment of low frequency sonophoresis only took 1/160 of the sound intensity and 1/4 of the time for the high frequency sonophoresis.
Furthermore, the research examined the uniformity of the sound field, and a wedge is designed to make a diffused field to compare the effect between a uniform one and its contrast. The result presented that the permeating drug with uninformative field is twice the amount of the normal exposure ultrasound field.
Based on the above results, the changes of frequency, sound intensity and sound field uniformity, the enhancement effects of the sonophoresis will be achieved.
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The bioeffect of ultrasound on human chondrocytesCheng, Yi-Li 29 July 2005 (has links)
Animal and clinical studies have shown an acceleration of bone healing by the application of pulsed low-intensity ultrasound (PLIUS). Several studies have reported that pulsed low-intensity ultrasound increase the synthesis of proteoglycan and type II collagen of cultured animal chondrocytes. The objectives of this study were to exam the bioeffect of pulsed low-intensity ultrasound on in vitro cultured human chondrocytes.
Human chondrocytes were isolated from the amputated polydactyly digit of six different 1 to 10 years patients and cultured in agarose suspension for 3 days before treatment. PLIUS with intensities of 3.6, 18, 48, 72 and 98 mW/cm2was respectively applied to human chondrocytes for a single 10-min per day treatment. A control group was treated without PLIUS.
The results demonstrated that PLIUS-treated human chondrocytes increased the proteoglycan synthesis compared with the control in a time-dependent manner. It is shown that the effect of 48 mW/cm2 is the most potent among a variety of PLIUS intensities tested determined by ELISA method. PLIUS at 48 mW/cm2 also increased type II collagen synthesis by up to 48.5+8.0% of the control determined by western blotting analysis. However, PLIUS has no significant influence on the cell proliferation of human chondrocytes compared with the control. It revealed that the PLIUS can enhance extracellular matrix synthesis. The response to PLIUS of chondrocytes harvested from 1 year old donor was significantly better than that of chondrocytes of 10 years old patient.
These observations may lead to a better understanding of the bioeffect of PLIUS on in vitro cultured human chondrovytes.
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Biological Effects of Paramecium Induced by UltrasoundChen, Ming-Kai 11 July 2001 (has links)
Abstract
Ultrasonic technique is widely used in medical application and food industry; however, much work has focused on harmful biological effects of tissues and cells by ultrasound exposure; only little information is mentioned about the beneficial biological effects of ultrasound. Thus, the objective of this thesis is to observe the beneficial biological activities of Paramecium induced by ultrasound exposure.
Since the structure or biophysical will stimulated into the interaction between ultrasound and living matter. When multi-cell creature is exposed by ultrasound, this reaction will lead the biological effect becomes complex. Therefore, a single cell creature is chosen to understand the beneficial biological effects induced by ultrasound exposure. The oscillation of the monad in response to the ultrasound radiation is simulated using Rayleigh-Plesset¡¦s bubble activation theory. The resonance frequency of the unicellular creature is then calculated. The diffuse field theory of Sabine is used to create a uniform sound field for the radiation experiment. The images obtained from a microscope can be analyzed and recorded by a personal computer. The number of cells was counted in the haemacytometer after irradiation.
The calculated resonant frequency range of the Paramecium shape is 0.2~0.27 MHz. The relative growth rate of the Paramecium suspensions exposed to ultrasound was about 20% slower than that of unexposed sample. It was found that the phenomenon of inhibition and destruction appeared during irradiation. Also, the growth curve is retarded during the period. The resonance frequency of the Paramecium vacuole is 0.5~1.09 MHz. The maximum relative growth rate was increasing 18% with 1MHz irradiation.
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The Biological Activation of Artemia Cyst Induced by Ultrasound ExposureChan, I-Hao 01 July 2003 (has links)
This proposal is about a project to study the biological activities of Artemia caused by ultrasound exposure. Ultrasound is employed clinically, for example, in medical diagnosis as a pulse-echo technique for obtaining information of tissue characteristics. It can also use the high-intensity-ultrasound to destroy the lump and pathogens of human tissues. In the other hand, the ultrasonic experiments of plant or insect tissues that contain gas in intercellular channels irradiate with megahertz frequencies of ultrasound, causing perturbation and destruction in nearby cells. Thus, the ultrasonic biological effect, in general, is destructive. However, ultrasound can be a noninvasive form of mechanical energy propagated in biologic organisms. This fact attracts our attention to identify the biologic mechanisms corresponding to the biological activation of Artemia induced by ultrasound exposure.
To perform the above-mentioned research, the oscillation of the Artemia in response to the ultrasound radiation is simulated using Rayleigh-Plesset¡¦s bubble activation theory. The gas body activation theory is to calculate the resonant frequencies of the Artemia at different stages of its life. The calculated resonant frequency range of the Artemia cyst shape and the embryonic cuticle is about 0.222~0.226 MHz and 2.46~4.71 MHz. By using the above mentioned resonance frequency of the Artemia, the maximum relative growth rate was increasing 16%. It was found that the Artemia of activation and increasing the hatching rate appeared during irradiation.
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Ultrasound-modulated optical tomography in soft biological tissuesSakadzic, Sava 17 September 2007 (has links)
Optical imaging of soft biological tissues is highly desirable since it is nonionizing
and provides sensitive contrast information which enables detection of physiological
functions and abnormalities, including potentially early cancer detection. However,
due to the diffusion of light, it is dificult to achieve simultaneously both good spatial
resolution and good imaging depth with the pure optical imaging modalities.
This work focuses on the ultrasound-modulated optical tomography - a hybrid
technique which combines advantages of ultrasonic resolution and optical contrast.
In this technique, focused ultrasound and optical radiation of high temporal co-herence are simultaneously applied to soft biological tissue, and the intensity of the
ultrasound-modulated light is measured. This provides information about the optical
properties of the tissue, spatially localized at the interaction region of the ultrasonic
and electromagnetic waves.
In experimental part of this work we present a novel implementation of high-resolution ultrasound-modulated optical tomography that, based on optical contrast,
can image several millimeters deep into soft biological tissues. A long-cavity confocal
Fabry-Perot interferometer was used to detect the ultrasound-modulated coherent
light that traversed the scattering biological tissue. Using 15-MHz ultrasound, we
imaged with high contrast light absorbing structures placed 3 mm below the surface
of chicken breast tissue. The resolution along the axial and the lateral directions with respect to the ultrasound propagation direction was better than 70 and 120ùm, respectively. This technology is complementary to other imaging technologies,
such as confocal microscopy and optical-coherence tomography, and has potential for
broad biomedical applications.
In the theoretical part we present various methods to model interaction be-tween the ultrasonic and electromagnetic waves in optically scattering media. We first extend the existing theoretical model based on the diffusing-wave spectroscopy
approach to account for anisotropic optical scattering, Brownian motion, pulsed ul-trasound, and strong correlations between the ultrasound-induced optical phase in-crements. Based on the Bethe-Salpeter equation, we further develop a more general
correlation transfer equation, and subsequently a correlation diffusion equation, for
ultrasound-modulated multiply scattered light. We expect these equations to be
applicable to a wide spectrum of conditions in the ultrasound-modulated optical tomography of soft biological tissues.
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Die Anwendung niederfrequenten Ultraschalls in der Wundbehandlung / Applications for low-frequency ultrasound in wound therapyNeugebauer, Reimund, Wollina, Uwe, Naumann, Gunther, Heinig, Birgit 11 October 2008 (has links) (PDF)
In einem von der Sächsischen Aufbaubank geförderten Verbundprojekt wird ein neuartiges Ultraschall-Behandlungsgerät entwickelt, das an der Klinik für Dermatologie und Allergologie des Krankenhauses Dresden- Friedrichstadt, einem Akademischen Lehrkrankenhaus der TU Dresden, im Rahmen einer klinischen Studie getestet wird. Durch die Messung peripherer topischer Durchblutungsparameter im Wundbereich unter dem Einfluss von niederfrequentem Ultraschall soll zur Objektivierung ablaufender Gewebeprozesse beigetragen werden. Das Ultraschall- Behandlungsgerät wurde gemeinsam vom Fraunhofer Institut für Werkzeugmaschinen und Umformtechnik Dresden, dem IMM Ingenieurbüro Mittweida sowie der Smart Material GmbH Dresden entwickelt / Within the framework of a cooperative project funded by Sächsische Aufbaubank, a new kind of ultrasound therapy system is under development and is being tested in clinical trials at the Department of Dermatology and Allergology at Dresden-Friedrichstadt Hospital, a university teaching hospital of Technische Universität Dresden. The measuring of peripheral topical parameters concerning blood circulation in wound areas under the influence of low-frequency ultrasound is expected to contribute to objectification of the relevant tissue processes. The ultrasound therapy system has been jointly developed by the Fraunhofer Institute for Machine Tools and Forming Technology, IMM Engineering Mittweida and Smart Material GmbH Dresden.
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Magnetoelastic coupling and relaxation processes in magnetic materials monitored by resonant ultrasound spectroscopyThomson, Richard Ian January 2013 (has links)
No description available.
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An Information Tracking Approach to the Segmentation of Prostates in Ultrasound ImagingXu, Robert Sheng 05 1900 (has links)
Outlining of the prostate boundary in ultrasound images is a very useful procedure performed and subsequently used by clinicians. The contribution of the resulting segmentation is twofold. First of all, the segmentation of the prostate glands can be used to analyze the size, geometry,
and volume of the gland. Such analysis is useful as it is known that the former quantities used in conjunction with a PSA blood test can be used as an indicator of malignancy in the gland itself. The second purpose of accurate segmentation is for treatment planning purposes. In brachetherapy, commonly used to treat localized prostate cancer, the accurate location of the prostate must be found so that the radioactive seeds can be placed precisely in the malignant regions. Unfortunately, the current method of segmentation of ultrasound images is performed manually by expert radiologists. Due to the abundance of ultrasound data, the process of manual segmentation can be extremely time consuming and inefficient. A much more desirable way to perform the segmentation process is through automatic procedures, which should be able to accurately and efficiently extract the boundary of the prostate gland with minimal user intervention. This is the ultimate goal of the proposed approach.
The proposed segmentation algorithm uses a probability distribution tracking framework
to accurately and efficiently perform the task at hand. The basis for this methodology is to extract image and shape features from available manually segmented ultrasound images for which the actual prostate region is known. Then, the segmentation algorithm seeks a region in new ultrasound images whose features closely mirror the learned features of known prostate regions. Promising results were achieved using this method in a series of in silico and in vivo experiments.
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Segmentation of 3D Carotid Ultrasound Images Using Weak Geometric PriorsSolovey, Igor January 2010 (has links)
Vascular diseases are among the leading causes of death in Canada and around the globe. A major underlying cause of most such medical conditions is atherosclerosis, a gradual accumulation of plaque on the walls of blood vessels. Particularly vulnerable to atherosclerosis is the carotid artery, which carries blood to the brain. Dangerous narrowing of the carotid artery can lead to embolism, a dislodgement of plaque fragments which travel to the brain and are the cause of most strokes. If this pathology can be detected early, such a deadly scenario can be potentially prevented through treatment or surgery. This not only improves the patient's prognosis, but also dramatically lowers the overall cost of their treatment.
Medical imaging is an indispensable tool for early detection of atherosclerosis, in particular since the exact location and shape of the plaque need to be known for accurate diagnosis. This can be achieved by locating the plaque inside the artery and measuring its volume or texture, a process which is greatly aided by image segmentation. In particular, the use of ultrasound imaging is desirable because it is a cost-effective and safe modality. However, ultrasonic images depict sound-reflecting properties of tissue, and thus suffer from a number of unique artifacts not present in other medical images, such as acoustic shadowing, speckle noise and discontinuous tissue boundaries. A robust ultrasound image segmentation technique must take these properties into account.
Prior to segmentation, an important pre-processing step is the extraction of a series of features from the image via application of various transforms and non-linear filters. A number of such features are explored and evaluated, many of them resulting in piecewise smooth images. It is also proposed to decompose the ultrasound image into several statistically distinct components. These components can be then used as features directly, or other features can be obtained from them instead of the original image. The decomposition scheme is derived using Maximum-a-Posteriori estimation framework and is efficiently computable.
Furthermore, this work presents and evaluates an algorithm for segmenting the carotid artery in 3D ultrasound images from other tissues. The algorithm incorporates information from different sources using an energy minimization framework. Using the ultrasound image itself, statistical differences between the region of interest and its background are exploited, and maximal overlap with strong image edges encouraged. In order to aid the convergence to anatomically accurate shapes, as well as to deal with the above-mentioned artifacts, prior knowledge is incorporated into the algorithm by using weak geometric priors. The performance of the algorithm is tested on a number of available 3D images, and encouraging results are obtained and discussed.
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