1.Mircocarriers' motion in rotating wall vessels.
Xiao MA ; Chun YANG ; Fengyuan ZHUANG
Journal of Biomedical Engineering 2010;27(6):1433-1438
Rotating wall vessels (RWVS), an ingenious apparatus for three-dimensional suspension culture, is widely used to build a simulated microgravity-effect on cell. Independent researchers have proposed hypotheses to illustrate why RWVS can simulate certain aspects of microgravity. Many of the hypotheses stated that the culture condition in RWVS is determined by the cellular mechanical environment which is a result of low fluid shear and microcarrier's motion. The microcarrier's motions consist of primary and secondary motions. In the light of the analysis of forces loaded by the microcarriers, some conclusions are drawn from the data on microcarriers' primary and secondary motions about which many simulations and observations have already been conducted.
Cell Culture Techniques
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instrumentation
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methods
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Gravitation
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Models, Theoretical
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Motion
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Rotation
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Stress, Mechanical
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Weightlessness Simulation
2.Ophthalmology in Aerospace.
Korean Journal of Aerospace and Environmental Medicine 2009;19(1):14-16
Let us study about the ophthalmology in the developing area of the environment of the aerospace. After the launch of Naroho (KSLV-I), Korean people are interested in the development of the technology and environment of the aerospace. It is important to the people who are engaged in the fields of the aerospace that the vision is affected by the environment of the aerospace so much. It can be hypoxia due to high altitude, blurred vision and lowering of the color sense due to mydriasis, disturbance of the light sense due to acceleration and vibration. But thanks to the development of refractive surgery, people can be an applicant for a pilot just 1 year after the surgery. The environment of the aerospace is also special to the area of the ophthalmology. There must be further study about the environment of the aerospace.
Acceleration
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Altitude
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Anoxia
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Light
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Linear Energy Transfer
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Mydriasis
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Ophthalmology
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Refractive Surgical Procedures
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Vibration
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Vision, Ocular
3.Study on noninvasive measurement of blood glucose based on optical rotation.
Hailong JIN ; Qin GE ; Wenxue HONG
Journal of Biomedical Engineering 2009;26(6):1391-1394
With the development of economy, the incidence of diabetes is keeping on rising. It has been a larger chief offender endangering human health. Glucose monitoring in time, accurately and continuously can provide the basis for the adjustment of diet, exercise and drug treatment project, and can control disease at the level of satisfaction degree. Noninvasive measurement of glucose avoids blood collection with high frequency, alleviates pain caused by blood sampling, and prevents infection. It comes with hope for the diabetic. In this article, we compare the kinds of techniques, introduce the theory, the problems of polarization rotation, the solving methods and the advantages, thus providing references for the noninvasive measurement of glucose.
Blood Glucose
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analysis
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Blood Glucose Self-Monitoring
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methods
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trends
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Diabetes Mellitus
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blood
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Humans
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Optical Rotation
4.Determination of the absolute configuration of natural products.
Chinese Journal of Natural Medicines (English Ed.) 2013;11(3):193-198
Structural elucidation of natural products is always one of the most important tasks for natural product researchers in related fields. Particularly, the absolute configuration (AC), being a great challenge for natural product chemists, has attracted much attention. During the past few decades, many techniques and approaches have been developed to determine the AC of natural products, including direct (or absolute) methods, e.g. X-ray diffraction (XRD), electronic and vibrational circular dichroism (ECD and VCD), and Raman optical activity (ROA), as well as indirect (or relative) methods using a reference or a derivatizing agent with known AC, e.g. CD with empirical rules and nuclear magnetic resonance (NMR) utilizing anisotropic effects of chiral derivatizing agents. However, none of the currently applied techniques is capable of dominating AC determination, since they each have their respective limitations corresponding to the different structural features. This mini review summarizes most of the techniques and methods which are commonly used in AC assignment of natural products, or have potential application prospects, and briefly describes their principles, advantages and limitations.
Biological Products
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chemistry
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Circular Dichroism
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Molecular Structure
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Optical Rotation
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X-Ray Diffraction
5.Development of Personalized Urination Recognition Technology Using Smart Bands.
Sung Jong EUN ; Taeg Keun WHANGBO ; Dong Kyun PARK ; Khae Hawn KIM
International Neurourology Journal 2017;21(Suppl 1):S76-S83
PURPOSE: This study collected and analyzed activity data sensed through smart bands worn by patients in order to resolve the clinical issues posed by using voiding charts. By developing a smart band-based algorithm for recognizing urination activity in patients, this study aimed to explore the feasibility of urination monitoring systems. METHODS: This study aimed to develop an algorithm that recognizes urination based on a patient's posture and changes in posture. Motion data was obtained from a smart band on the arm. An algorithm that recognizes the 3 stages of urination (forward movement, urination, backward movement) was developed based on data collected from a 3-axis accelerometer and from tilt angle data. Real-time data were acquired from the smart band, and for data corresponding to a certain duration, the absolute value of the signals was calculated and then compared with the set threshold value to determine the occurrence of vibration signals. In feature extraction, the most essential information describing each pattern was identified after analyzing the characteristics of the data. The results of the feature extraction process were sorted using a classifier to detect urination. RESULTS: An experiment was carried out to assess the performance of the recognition technology proposed in this study. The final accuracy of the algorithm was calculated based on clinical guidelines for urologists. The experiment showed a high average accuracy of 90.4%, proving the robustness of the proposed algorithm. CONCLUSIONS: The proposed urination recognition technology draws on acceleration data and tilt angle data collected via a smart band; these data were then analyzed using a classifier after comparative analyses with standardized feature patterns.
Acceleration
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Arm
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Humans
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Posture
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Urination*
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Vibration
6.Recovery and Adsorption Rate of Murine Norovirus Using NanoCeram(R) Filters.
Yun Hee KIM ; Seok Jea JANG ; Ji Youn PARK ; Jung Hwan OH ; Geun Su KIM ; Tae Seung KIM ; Oh Sang KWON ; Jin Seok HAN ; Won Hwa JHEONG
Journal of Bacteriology and Virology 2011;41(1):55-61
This study investigated the recovery and absorption rates of murine norovirus, a surrogate for human norovirus, by using NanoCeram(R) filters which served as a tool for recovering viruses. In the study, two types of NanoCeram(R) filters were employed: one was a cartridge type and the other was a disc type (phi 47 mm) whose surface area is 75 times smaller than the cartridge type. The analytical method was the real-time reverse transcription-polymerase chain reaction (RT-PCR). The study found that the average recovery rates of the cartridge type and the disc type were 30.9% and 29.5% respectively. Since these two rates were very close to each other, the adsorption rate of the cartridge type could be predicted with the disc type. Analyzing recovery and absorption rates of the disc type based on different filtered volumes showed that when the volume increased from 0.5 L to 20 L, the average recovery rate rose from 14.78% to 30.41 %, while the average absorption rate dropped from 56.33% to 10.48%. The increase in turbidity from less than 1 NTU to less than 3 NTU raised the average recovery rate from 47.23% to 82.84%.
Absorption
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Adsorption
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Humans
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Norovirus
7.Numerical simulation of microcarrier motion in a rotating wall vessel bioreactor.
Zhi-Hao JU ; Tian-Qing LIU ; Xue-Hu MA ; Zhan-Feng CUI
Biomedical and Environmental Sciences 2006;19(3):163-168
OBJECTIVETo analyze the forces of rotational wall vessel (RWV) bioreactor on small tissue pieces or microcarrier particles and to determine the tracks of microcarrier particles in RWV bioreactor.
METHODSThe motion of the microcarrier in the rotating wall vessel (RWV) bioreactor with both the inner and outer cylinders rotating was modeled by numerical simulation.
RESULTSThe continuous trajectory of microcarrier particles, including the possible collision with the wall was obtained. An expression between the minimum rotational speed difference of the inner and outer cylinders and the microcarrier particle or aggregate radius could avoid collisions with either wall. The range of microcarrier radius or tissue size, which could be safely cultured in the RWV bioreactor, in terms of shear stress level, was determined.
CONCLUSIONThe model works well in describing the trajectory of a heavier microcarrier particle in rotating wall vessel.
Bioreactors ; Computer Simulation ; Microspheres ; Motion ; Porosity ; Rheology ; Rotation ; Stress, Mechanical ; Tissue Engineering ; methods
8.Study on optical energy transmission in biotic tissues by Monte Carlo method.
Xiaonan REN ; Shoushui WEI ; Xianzhang YANG ; Di GAO
Journal of Biomedical Engineering 2010;27(3):652-657
Biotic tissues are a kind of highly scattering random media; studies on laser light propagation in biotic tissues play an important role in bio-medical diagnostics and therapeutics. The propagation and distribution of infinitely narrow photon beam in tissues are simulated by Monte Carlo method in this paper. Also presented are the energy distribution with regard to depths, light distribution in tissues, reflection and transmittance on the upper and lower surface. The optical parameters adopted in this study are g, albedo and microa, which have influence on energy distribution. The results show: The energy distribution decreases more quickly with the increase of depths and reveals a peak value close to the surface; g factor plays an important part in the lost energy on the upper surface and lower surface; the decrease of g factor causes weaking of the forward moving ability, so the penetration depth becomes smaller and the energy becomes dispersives variation of albedo has distinct effect on the shallow and deep tissues.
Computer Simulation
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Energy Transfer
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Light
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Models, Biological
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Monte Carlo Method
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Optics and Photonics
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Photochemotherapy
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methods
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Scattering, Radiation
9.Joint correction for motion artifacts and off-resonance artifacts in multi-shot diffusion magnetic resonance imaging.
Wenchuan WU ; Sheng FANG ; Hua GUO
Journal of Biomedical Engineering 2014;31(3):657-670
Aiming at motion artifacts and off-resonance artifacts in multi-shot diffusion magnetic resonance imaging (MRI), we proposed a joint correction method in this paper to correct the two kinds of artifacts simultaneously without additional acquisition of navigation data and field map. We utilized the proposed method using multi-shot variable density spiral sequence to acquire MRI data and used auto-focusing technique for image deblurring. We also used direct method or iterative method to correct motion induced phase errors in the process of deblurring. In vivo MRI experiments demonstrated that the proposed method could effectively suppress motion artifacts and off-resonance artifacts and achieve images with fine structures. In addition, the scan time was not increased in applying the proposed method.
Artifacts
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Diffusion Magnetic Resonance Imaging
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Humans
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Image Processing, Computer-Assisted
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Motion
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Phantoms, Imaging
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Vibration
10.The Influence of Enzyme (Urokinase(R)) and Liquefaction of Vitreous on Absorption of Simulated Vitreous Hemorrhages.
Journal of the Korean Ophthalmological Society 1978;19(1):9-18
This investigation was undertaken to study the mechanisms involved in the absorption of blood from the vitreous, and was divided into following experimental groups: A) Eyes injected with 0.1 cc whole blood (7 eyes). B) Eyes injected with 0.1 hemolyzed blood (7 eyes). C) Eyes injected with 0.1 cc (12IU/0.1ml) urokinase solution after 0.1 cc whole blood injection (7 eyes). D) Eyes injected with 0.1 cc whole blood after 0.5 cc vitreous aspiration (7 eyes). E) Combined group of C) and D) (7 eyes). In each experimental group. simulated vitreous hemorrhages were induced in rabbits by intravitreal injection of 0.1 ml autologous radioactive chronim (51Cr) tagged blood through the pars plana at 12 o'clock position. Thereafter, the author counted the rates of change of radioactivity of the eyes with a scintillation counter everyone day during 10 days and their percentages were obtained. The results obtained were as follows: 1) The average rate of removal of whole blood group from the vitreous cavity(1/2-life; time required for 50% of the injected radioactivity to disappear) was approximately 1/5 times those of hemolyzed group and combined group, and 2/5 times that of urokinase group, 3/5 times that of vitreous aspiration group. 2) The average rate of removal of w hloe blood group from the vitreous cavity (3/4-life; time required for 75% of the injected radioactivity to disappear) was approximately 1/3 times that of hemolyzed blood, and 1/5 times those of urokinase group and combined group. 3) From those results, it was concluded that diffusion of blood elements and hemolysis, alternation of vitreous structure itself were closely related to the absorption of vitreous hemorrhage.
Absorption*
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Diffusion
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Hemolysis
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Intravitreal Injections
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Rabbits
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Radioactivity
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Scintillation Counting
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Urokinase-Type Plasminogen Activator
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Vitreous Hemorrhage*