22 research outputs found

    NIR camera for early detection of diabetic ulcers

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    The purpose of this Creative Inquiry is to test whether near-infrared (NIR) imaging devices can detect areas of skin at risk for ulceration in diabetic patients. Venous blood accumulation, or high levels of deoxygenated blood within a tissue, can indicate poor blood circulation and increased risk of ulceration. Here we propose to detect venous blood in tissues using differences in optical spectra of oxygenated vs. deoxygenated blood in NIR region. We previously designed and built a prototype scanner with three integrated NIR light sources that is being tested at MUSC. Our current work is focused on testing of improved NIR illumination systems and improved NIR imaging device, and our second prototype that uses a more sensitive Raspberry Pi-controlled camera and advanced NIR light sources will provide significantly improved image quality. Upon success, the ultimate goal of this project is to manufacture a cheap, portable NIR camera for skin self-monitoring by diabetic patients

    Macro-AFM model

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    An Atomic Force Microscope (AFM) is an important tool in modern nanoscience, capable of producing surface maps at resolutions below 1 nanometer, which is impossible for other methods. Despite AFM\u27s often use, it is often difficult for students to understand their work because all measurement processes take place at micro- and nano-scale. The goal of this project is to create a macro scale model, which will serve as an educational tool to introduce the principles behind AFM to undergraduate and high school students. Currently, a fully automatic microprocessor-controlled surface scanning block has been built and successfully tested with a scan area of ca. one square foot. Continued work includes designing and building of a topography measurement block that will work on the same principle as a real AFM does at nano-level. We expect that macro AFM building an image using AFM techniques will empower instructors to show the concepts, and to spark interest of potential students in Bioengineering

    Origin and distribution of chum salmon <i>Oncorhynchus keta</i> stocks in the western Bering Sea and North-West Pacific in 2009 and 2010

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    Intraspecific structure of feeding and prespawning aggregations of chum salmon in the western Bering Sea in September-October of 2009 and 2010 and in the North-West Pacific in June-July of 2009 and 2010 is investigated on the data of trawl surveys conducted by Pacific Fish. Res. Center (TINRO) aboard RV Professor Kaganovsky in the framework of the Bering-Aleutian Salmon International Survey, second stage (BASIS-II). In total, 4246 specimens of chum salmon from mixed aggregations were subjected to biological analysis, and for 2462 of them the intraspecific status was identified on the base of scale structure (the scale baseline included the scale data for 11460 chum individuals belonged to 43 local stocks from Asia and North America). Both for the Bering Sea and Pacific Ocean, domination of Russian stocks is defined, contribution of Japanese stocks is significantly lower and lowered comparing with previous years, as 2002-2004 and 2006, and contribution of North American stocks is poor and does not exceed statistical error value of the method. For the western Bering Sea the ratio by countries of the fish origin is the following: Russia 93.8-95.3 %, Japan 2.9-5.2 %, USA 1.0-1.9 % for immature chum salmon in autumn of 2009-2010; and Russia 88.8 %, Japan 9.8 %, USA 1.4 % for maturing chum salmon in autumn of 2009. For the North-West Pacific in summer of 2009-2010, the ratio is similar: Russia 75.4-88.7 %, Japan 10.1-23.9 %, USA 0.7-1.2 % for immature chum salmon; and Russia 81.0-83.0 %, Japan 15.9-17.7 %, USA 1.1-1.3 % for maturing chum salmon. Based on this ratio, the relative abundance of stock complexes by countries of origin is assessed (106 ind.): Russia 107.81-123.32, Japan 3.75-5.98, USA 1.15-2.33 for immature chum salmon in the western Bering Sea in 2009 and 2010; Russia 6.34, Japan 0.70, USA 0.10 for maturing chum salmon in the western Bering Sea in 2009; Russia 19.27-37.74, Japan 6.11-4.30, USA 0.18-0.51 for immature chum salmon in the North-West Pacific in 2009 and 2010; and Russia 29.02-42.60, Japan 5.56-9.31, USA 0.38-0.68 for maturing chum salmon in the North-West Pacific in 2009 and 2010. For the immature chum salmon in the North-Western Pacific, the assessments of intraspecific composition and relative abundance of different groups should be considered as preliminary results, because of insufficient number of the scale samples

    Electron-phonon relaxation and excited electron distribution in zinc oxide and anatase

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    We propose a first-principle method for evaluations of the time-dependent electron distribution function of excited electrons in the conduction band of semiconductors. The method takes into account the excitations of electrons by external source and the relaxation to the bottom of conduction band via electron-phonon coupling. The methods permits calculations of the non-equilibrium electron distribution function, the quasi-stationary distribution function with steady-in-time source of light, the time of setting of the quasi-stationary distribution and the time of energy loss via relaxation to the bottom of conduction band. The actual calculations have been performed for titanium dioxide in the anatase structure and zinc oxide in the wurtzite structure. We find that the quasi-stationary electron distribution function for ZnO is a fermi-like curve that rises linearly with increasing excitation energy whereas the analogous curve for anatase consists of a main peak and a shoulder. The calculations demonstrate that the relaxation of excited electrons and the setting of the quasi-stationary distribution occur within the time no more than 500 fsec for ZnO and 100 fsec for anatase. We also discuss the applicability of the effective phonon model with energy-independent electron-phonon transition probability. We find that the model only reproduces the trends in changing of the characteristic times whereas the precision of such calculations is not high. The rate of energy transfer to phonons at the quasi-stationary electron distribution also have been evaluated and the effect of this transfer on the photocatalyses has been discussed. We found that for ZnO this rate is about 5 times less than in anatase.Comment: 21 p., 9 figure

    ОСНОВЫ ТЕОРИИ ХИМИЧЕСКИХ ПРОЦЕССОВ И РЕАКТОРОВ

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    The monograph examines the theoretical problems of chemical technology processes that have historically developed through the creation of building materials, metallurgy, the production of inorganic and organic compounds, as well as the processing of agricultural products into food products. Widely using mathematical methods of modeling, the method of theoretical generalizations, the graph method, the authors give new systems of equations of statistics and kinetics of processes. The problems of theory and calculation methods for chemical reactors are discussed, which are considered the basis of the "processor unit" in technological production, and also the problems of intensification and optimization of chemical-technological processes are considered. Indexing: &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp; &nbsp;&nbsp;В монографии рассматриваются теоретические проблемы процессов химической технологии, которые исторически развивались на основе создания строительных материалов, металлургии, производства неорганических и органических соединений, а также переработки сельхоз продукции в пищевые продукты. Широко используя математические методы моделирования, метод теоретических обобщений, метод графов авторы дают новые системы уравнений статистики и кинетики процессов. Обсуждаются вопросы теории и методы расчета химических реакторов, которые считают основной «процессорной единицей» в технологическом производстве, а также рассматривают проблемы интенсификации и оптимизации химико-технологических процессов. Індексація: &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp; &nbsp; &nbsp

    Development and Validation of a Smartphone Heart Rate Acquisition Application for Health Promotion and Wellness Telehealth Applications

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    Objective. Current generation smartphones' video camera technologies enable photoplethysmographic (PPG) acquisition and heart rate (HR) measurement. The study objective was to develop an Android application and compare HRs derived from a Motorola Droid to electrocardiograph (ECG) and Nonin 9560BT pulse oximeter readings during various movement-free tasks. Materials and Methods. HRs were collected simultaneously from 14 subjects, ages 20 to 58, healthy or with clinical conditions, using the 3 devices during 5-minute periods while at rest, reading aloud under observation, and playing a video game. Correlation between the 3 devices was determined, and Bland-Altman plots for all possible pairs of devices across all conditions assessed agreement. Results. Across conditions, all device pairs showed high correlations. Bland-Altman plots further revealed the Droid as a valid measure for HR acquisition. Across all conditions, the Droid compared to ECG, 95% of the data points (differences between devices) fell within the limits of agreement. Conclusion. The Android application provides valid HRs at varying levels of movement free mental/perceptual motor exertion. Lack of electrode patches or wireless sensor telemetric straps make it advantageous for use in mobile-cell-phone-delivered health promotion and wellness programs. Further validation is needed to determine its applicability while engaging in physical movement-related activities

    ЕКОЛОГІЯ У ВИРОБНИЦТВІ ТУГОПЛАВКИХ НЕМЕТАЛЕВИХ І СИЛІКАТНИХ МАТЕРІАЛІВ

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    The main issues of the interaction of production factors (production process, technological implementation, conditions of the production process, form harmful substances and factors) and the environment (workers, living organisms outside the process) in the production of refractory non-metallic and silicate materials are considered. Indexing: &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp; &nbsp;&nbsp;Розглянуто основні питання взаємодії виробничих факторів (виробничий процес, технологічні впровадження, умови виробничого процесу, що утворюють шкідливі речовини і фактори) та навколишнього середовища (працівники, живі організми за межами технологічного процесу) при виробництві тугоплавких неметалевих і силікатних матеріалів. Призначено для студентів спеціальності: 101 «Екологія» та 161 «Хімічна технологія та інженерія» Індексація: &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp; &nbsp
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