Single Phase Turbulent Flow Regime Characterization Using Image Processing Techniques

Optical techniques are useful for non- contacting flow measurements such as high pressure and high temperature situations. Certain optical flow measurement technique works well only in turbulent flow regime. Hence, in order to improve the optical flow measurement technique, there is a need to characterize the single phase turbulent flow regime using image processing technique. This will allow the optical flow measurement technique to be applied at the turbulent flow regime, increasing its accuracy. Crone et. al. stated in his Optical Particle Velocimetry (OPV) work that OPV works best in turbulent flow regime. It cannot be applied to transitional flow regime. Image processing techniques was applied on 50 frames of Crone et. al.’s single phase flow images to characterize the single phase turbulent flow regime. Experimental results developed by Crone et. al. was used as the theoretical data to validate the accuracy of the techniques

Single Phase Turbulent Flow Regime Characterization Using Image Processing Techniques

Optical techniques are useful for non- contacting flow measurements such as high pressure and high temperature situations. Certain optical flow measurement technique works well only in turbulent flow regime. Hence, in order to improve the optical flow measurement technique, there is a need to characterize the single phase turbulent flow regime using image processing technique. This will allow the optical flow measurement technique to be applied at the turbulent flow regime, increasing its accuracy. Crone et. al. stated in his Optical Particle Velocimetry (OPV) work that OPV works best in turbulent flow regime. It cannot be applied to transitional flow regime. Image processing techniques was applied on 50 frames of Crone et. al.’s single phase flow images to characterize the single phase turbulent flow regime. Experimental results developed by Crone et. al. was used as the theoretical data to validate the accuracy of the techniques

Mammography

In this volume, the topics are constructed from a variety of contents: the bases of mammography systems, optimization of screening mammography with reference to evidence-based research, new technologies of image acquisition and its surrounding systems, and case reports with reference to up-to-date multimodality images of breast cancer. Mammography has been lagged in the transition to digital imaging systems because of the necessity of high resolution for diagnosis. However, in the past ten years, technical improvement has resolved the difficulties and boosted new diagnostic systems. We hope that the reader will learn the essentials of mammography and will be forward-looking for the new technologies. We want to express our sincere gratitude and appreciation?to all the co-authors who have contributed their work to this volume

Computational framework for identification of cancerous nodules in prostate based on instrumented palpation

The interplay between engineering and medical research plays a major role in advancing the healthcare technologies. Novel medical devices have been developed to improve the diagnosis and treatment plans for patients with pathological conditions such as prostate cancer (PCa). In this context, in silico modelling has been a valuable tool as it is complementary to traditional trial-and-error approaches, particularly in the area of nodule identification in soft tissue. The goal of this thesis is to develop a computational framework of detecting and characterizing the presence of PCa, based on instrumented probing. The proposed methodologies involve Finite-Element simulations, inverse analysis and probability-based methods, using models reconstructed from medical imaging and histological data. The proposed methods are later validated using experimental measurements from instrumented probing on ex-vivo prostates. It is expected that the in-silico framework can serve as a complementary tool to the medical devices and to improve the effectiveness of current methods for early PCa diagnosis.James-Watt ScholarshipHeriot-Watt University - Annual Fund Gran

How sonoporation disrupts cellular structural integrity: morphological and cytoskeletal observations

Posters: no. 1Control ID: 1672429OBJECTIVES: In considering sonoporation for drug delivery applications, it is essential to understand how living cells respond to this puncturing force. Here we seek to investigate the effects of sonoporation on cellular structural integrity. We hypothesize that the membrane morphology and cytoskeletal behavior of sonoporated cells under recovery would inherently differ from that of normal viable cells. METHODS: A customized and calibrated exposure platform was developed for this work, and the ZR-75-30 breast carcinoma cells were used as the cell model. The cells were exposed to either single or multiple pulses of 1 MHz ultrasound (pulse length: 30 or 100 cycles; PRF: 1kHz; duration: up to 60s) with 0.45 MPa spatial-averaged peak negative pressure and in the presence of lipid-shelled microbubbles. Confocal microscopy was used to examine insitu the structural integrity of sonoporated cells (identified as ones with exogenous fluorescent marker internalization). For investigations on membrane morphology, FM 4-64 was used as the membrane dye (red), and calcein was used as the sonoporation marker (green); for studies on cytoskeletal behavior, CellLight (green) and propidium iodide (red) were used to respectively label actin filaments and sonoporated cells. Observation started from before exposure to up to 2 h after exposure, and confocal images were acquired at real-time frame rates. Cellular structural features and their temporal kinetics were quantitatively analyzed to assess the consistency of trends amongst a group of cells. RESULTS: Sonoporated cells exhibited membrane shrinkage (decreased by 61% in a cell’s cross-sectional area) and intracellular lipid accumulation (381% increase compared to control) over a 2 h period. The morphological repression of sonoporated cells was also found to correspond with post-sonoporation cytoskeletal processes: actin depolymerization was observed as soon as pores were induced on the membrane. These results show that cellular structural integrity is indeed disrupted over the course of sonoporation. CONCLUSIONS: Our investigation shows that the biophysical impact of sonoporation is by no means limited to the induction of membrane pores: e.g. structural integrity is concomitantly affected in the process. This prompts the need for further fundamental studies to unravel the complex sequence of biological events involved in sonoporation.postprin

Developmental delays and subcellular stress as downstream effects of sonoporation

Posters: no. 2Control ID: 1672434OBJECTIVES: The biological impact of sonoporation has often been overlooked. Here we seek to obtain insight into the cytotoxic impact of sonoporation by gaining new perspectives on anti-proliferative characteristics that may emerge within sonoporated cells. We particularly focused on investigating the cell-cycle progression kinetics of sonoporated cells and identifying organelles that may be stressed in the recovery process. METHODS: In line with recommendations on exposure hardware design, an immersion-based ultrasound platform has been developed. It delivers 1 MHz ultrasound pulses (100 cycles; 1 kHz PRF; 60 s total duration) with 0.45 MPa peak negative pressure to a cell chamber that housed HL-60 leukemia cells and lipid-shelled microbubbles at a 10:1 cell-tobubble ratio (for 1e6/ml cell density). Calcein was used to facilitate tracking of sonoporated cells with enhanced uptake of exogenous molecules. The developmental trend of sonoporated cells was quantitatively analyzed using BrdU/DNA flow cytometry that monitors the cell population’s DNA synthesis kinetics. This allowed us to measure the temporal progression of DNA synthesis of sonoporated cells. To investigate whether sonoporation would upset subcellular homeostasis, post-exposure cell samples were also assayed for various proteins using Western blot analysis. Analysis focus was placed on the endoplasmic reticulum (ER): an important organelle with multi-faceted role in cellular functioning. The post-exposure observation time spanned between 0-24 h. RESULTS: Despite maintaining viability, sonoporated cells were found to exhibit delays in cell-cycle progression. Specifically, their DNA synthesis time was lengthened substantially (for HL-60 cells: 8.7 h for control vs 13.4 h for the sonoporated group). This indicates that sonoporated cells were under stress: a phenomenon that is supported by our Western blot assays showing upregulation of ER-resident enzymes (PDI, Ero1), ER stress sensors (PERK, IRE1), and ER-triggered pro-apoptotic signals (CHOP, JNK). CONCLUSIONS: Sonoporation, whilst being able to facilitate internalization of exogenous molecules, may inadvertently elicit a cellular stress response. These findings seem to echo recent calls for reconsideration of efficiency issues in sonoporation-mediated drug delivery. Further efforts would be necessary to improve the efficiency of sonoporation-based biomedical applications where cell death is not desirable.postprin