Fabrication of Microfluidic Devices to Study Confined Collective Migration of Breast Cancer Cells

Cells in our body mostly exist in confined environments. They are surrounded by neighboring cells, tissues, and the extracellular matrix. The changes in these surrounding environments influence cell behaviors. Therefore, studying cell mechanics plays a significant role to understand how cancer cells migrate and what primary factors that control cancer metastasis. Many studies have been developed to study how cancer cells migrate in the body. However, these experiments in vivo are complicated and incredibly challenging. Another approach is to perform experiments in vitro instead. However, to obtain relevant results, a specific experimental apparatus must be designed to confine cells. Glass slides and Petri dishes have been used in the traditional cell biology experiments, but these experiments are limited to being performed on only two-dimensional open surfaces. In recent decades, microfluidic devices have been developed and widely used in cell biology for studying single-cell migration in confinement. Here, we develop a microfluidic device to study breast cancer cells. Various degrees of vertical confinement chambers are in progress to be designed in SOLIDWORKS. These chambers are connected at a common center where all the inlets meet. We expect more than one experiment to be done at once by using our design. Hence, we will be able to collect data and compare how breast cancer cells migrate differently under various degrees of vertical confinement at the same time. The results will have the potential to provide clinical implications such as aggressive cancer phenotype, poor prognosis, and high tendency to metastasis

India subnational extended cost-effectiveness analysis : methods and lessons

Research plans are outlined in this presentation, with regard to collecting and updating data on tobacco use, and the cost-effectiveness of tobacco control measures in India. The team will strengthen existing relationships with State finance ministries, Health research centers, Civil Society organizations, and advocacy groups for states and at the federal level. In India, State governments set their own VAT (value added tax) rates for cigarettes, which is over and above the central excise tax

M-LEARNING APPLICATION IN TEACHING BADMINTON FOR PHYSICAL EDUCATION STUDENTS IN VIETNAM

The article evaluates the efficacy of M-learning in instructing the Badminton course for K14 university students at the University of Sports and Physical Education in Ho Chi Minh City, Vietnam. Utilizing an experimental design, it contrasts the outcomes of two groups: the K13 students who were taught through conventional face-to-face methods and the K14 students who engaged in blended learning. Both groups were exposed to identical content and assessment procedures. The findings indicate that students in the blended learning approach outperformed their peers in the traditional setting. The study also delves into resource utilization and collects feedback from learners, underscoring the advantages of M-learning in Badminton instruction.  Article visualizations

Grammar-Based Set-Theoretic Formalization of Emergence in Complex Systems

Master'sMASTER OF SCIENC

Improved Time and Frequency Synchronization Algorithm for 802.11a Wireless Standard based on the SIGNAL Field

International audienceTime and frequency synchronization in the IEEE 802.11a OFDM (Orthogonal Frequency Division Multiplexing) wireless communication system is addressed in this paper. Usually synchronization algorithms rely only on training sequences specified by the standard. To enhance the synchronization between stations, we propose to extract known information by both the transmitter and the receiver at the IEEE 802.11a physical layer to be then exploited by the receiver in addition to the training sequences. Indeed the parts of the identified SIGNAL field are either known or predictable from the RtS (Request to Send) control frame when the CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) mechanism is triggered jointly to bit-rate adaptation algorithms to the channel. Moreover the received RtS control frame allows the receiver to estimate the channel before time synchronization stage improving then the performance of the proposed synchronization algorithm. Simulation results show that the performance of the proposed synchronization algorithm is improved as compared to existing algorithms

Wireless, Handheld Diffuse Reflectance Spectroscopy to Quantify Tissue Microvascular Hemodynamics

Diffuse Reflectance Spectroscopy (DRS) is a non-invasive optical method to characterize tissue optical properties for disease diagnosis and health monitoring. Two optical fibers are often used in a DRS system: one to deliver light to the tissue and the other to gather diffuse reflectance spectra, which provide quantitative details about the structure and composition of the tissue. The conventional DRS system, however, is expensive, bulky, and composed of fragile optical fibers and multiple electrical connections. Here we propose to build a wireless, handheld, and fiber-less diffuse optical spectroscopy system. Unfortunately, the diffusion approximation utilized for data analysis of the conventional DRS is no longer valid due to the non-contact configuration of the fiber-less DRS system. To analyze the collected diffuse reflectance spectra using the handheld spectrometer, we have built a reflectance lookup table (LUT) using Monte Carlo simulation. Also, we have conducted some tests using a blood liquid phantom that is made of water, intralipid, and bovine blood, simulating human tissues to evaluate our DRS system with our LUT to extract the phantom\u27s oxygen saturation (SO2). The results show that portable spectrometer estimated SO2 values agree with the traditional DRS system. These results demonstrate that our handheld equipment can accurately estimate tissue oxygenation and hemoglobin levels, thus providing a mean of rapid quantitative tools assessing microvascular hemodynamics

Portable Diffuse Reflectance Spectroscopy for Non-invasive and Quantitative Assessment of the Parathyroid Glands Viability During Surgery

Portable Diffuse Reflectance Spectroscopy for Non-invasive and Quantitative Assessment of the Parathyroid Glands Viability During Surgery Mark Romine, Linh Luong, Alex Moazzen, Katie Cho and Paul Lee The parathyroid glands (PTGs) are responsible for the regulation of calcium levels in the blood by secreting a parathyroid hormone. This parathyroid hormone then regulates the body’s absorption, storage, and secretion of calcium, which can directly affect the way muscles and nerves operate. PTGs are often at risk of damage, or accidental removal during thyroid surgeries, because it is challenging to identify PTGs and to determine their viability. Current methods of visual inspections are often subjective and blood panels have long processing times. Diffuse Reflectance Spectroscopy (DRS) may provide a solution for the noninvasive, rapid, and quantitative assessment of the viability of PTGs. DRS is a non-invasive technique that uses the reflectance properties of tissue to quantify the hemoglobin (Hb) and concentrations and tissue oxygenation. DRS consists of a white LED (wavelength 400nm – 700nm) for a light source, a compact spectrometer that records tissue reflectance and a fiber optic probe. In this project, we have built a portable DRS system and verified the performance of the prototyped DRS system. We have characterized a signal-to-noise ratio (SNR) on tissue simulating optical phantom and the computed SNR is around 40 dB as expected. Also, we have demonstrated that DRS can measure the change in oxygenation values in our blood phantom testing. These bench-top tests show that our protype is ready for human study during a thyroid surgery

Low-Dose CT Image Denoising using Image Decomposition and Sparse Representation

X-ray computed tomography (CT) is now a widely used imaging modality for numerous medical purposes. The risk of high X-ray radiation may induce genetic, cancerous and other diseases, demanding the development of new image processing methods that are able to enhance the quality of low-dose CT images. However, lowering the radiation dose increases the noise in acquired images and hence affects important diagnostic information. This paper contributes an efficient denoising method for low-dose CT images. A noisy image is decomposed into three component images of low, medium and high frequency bands; noise is mainly presented in the medium and high component images. Then, by exploiting the fact that a small image patch of the noisy image can be approximated by a linear combination of several elements in a given dictionary of noise-free image patches generated from noise-free images taken at nearly the same position with the noisy image, noise in these medium and high component images are effectively eliminated.Specifically, we give new solutions for image decomposition to easily control the filter parameters, for dictionary construction to improve the effectiveness and reduce the running-time. Instead of using a large dataset of patches, only a structured small part of patches extracted from the raw data is used to form a dictionary, to be used in sparse coding. In addition, we illustrate the effectiveness of the proposed method in preserving image details which are subtle but clinically important. Experimental results conducted on both synthetic and real noise data demonstrate that the proposed method is competitive with the state-of-the-art methods