Atmospheric pressure plasma measurement and control

Timo GANS 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

A switched-system approach to formation control and heading consensus for multi-robot systems

Jin, J.,Ramirez, J. P.,Wee, S.,Lee, D.,Kim, Y.,Gans, N. SPRINGER SCIENCE + BUSINESS MEDIA 2018 Intelligent service robotics Vol.11 No.2

<P>This paper proposes a novel, hybrid and decentralized, switched-system approach for formation and heading consensus control of mobile robots under switching communication topology, including collision avoidance capability. The set of robots consists of nonholonomic wheeled mobile robots and can include a teleoperated UAV. The key feature of this approach is a virtual graph, which is derived by adding a set of relative translation vectors to the real graph of the multiple robots. Our approach results in the robots in the real graph moving to the desired formation and achieving heading consensus while the virtual robots on the virtual graph reach pose consensus. If any robot detects a nearby obstacle or other robot, the robot will temporarily move along an avoidance vector, which is perpendicular and positively projected onto the attractive vector, such that collision is avoided while minimally deviating from its formation control path. Experimental results are provided by two different research groups to demonstrate the effectiveness of our approach. These experiments extend the theoretical development by introducing a teleoperated quadrotor as a leader robot of the multi-robot systems. The same control law works for the extended system, with no modifications.</P>

Innervation Patterns of Autonomic Axons in the Human Endocrine Pancreas

Rodriguez-Diaz, Rayner,Abdulreda, Midhat ,H.,Formoso, Alexander ,L.,Gans, Itai,Ricordi, Camillo,Berggren, Per-Olof,Caicedo, Alejandro Elsevier 2011 Cell metabolism Vol.14 No.1

<P><B>Summary</B></P><P>The autonomic nervous system regulates hormone secretion from the endocrine pancreas, the islets of Langerhans, thus impacting glucose metabolism. The parasympathetic and sympathetic nerves innervate the pancreatic islet, but the precise innervation patterns are unknown, particularly in human. Here we demonstrate that the innervation of human islets is different from that of mouse islets and does not conform to existing models of autonomic control of islet function. By visualizing axons in three dimensions and quantifying axonal densities and contacts within pancreatic islets, we found that, unlike mouse endocrine cells, human endocrine cells are sparsely contacted by autonomic axons. Few parasympathetic cholinergic axons penetrate the human islet, and the invading sympathetic fibers preferentially innervate smooth muscle cells of blood vessels located within the islet. Thus, rather than modulating endocrine cell function directly, sympathetic nerves may regulate hormone secretion in human islets by controlling local blood flow or by acting on islet regions located downstream.</P> <P><B>Highlights</B></P><P>► Detailed quantitative analysis of the innervation of mouse and human islets ► Human endocrine cells are sparsely innervated ► Sympathetic axons innervate vascular smooth muscle cells deep inside human islets ► Autonomic control of human islets may use unique mechanisms</P>

Camera relative pose estimation for visual servoing using quaternions

Fathian, Kaveh,Jin, Jingfu,Wee, Sung-Gil,Lee, Dong-Ha,Kim, Yoon-Gu,Gans, Nicholas R. Elsevier 2018 Robotics and autonomous systems Vol.107 No.-

<P><B>Abstract</B></P> <P>We present a novel approach to estimate the rotation and translation between two camera views from a minimum of five matched points in the images. Our approach simultaneously recovers the 3D structure of the points up to a common scale factor, and is immune to a variety of problems that plague existing methods that are based on the Euclidean homography or Essential matrix. Methods based on homography only function when feature points are coplanar in 3D space. Methods based on the Essential matrix often lose accuracy as the translation between two camera views goes to zero or when points are coplanar. By recovering the rotation and translation independently using quaternions, our algorithm eschews the shortcomings of these methods. Moreover, we do not impose any constraints on the 3D configuration of the points (such as coplanar or non-coplanar constraints). Our method is particularly well-suited for Position-Based Visual Servoing (PBVS) applications. Investigations using both simulations and experiments validate the new method. Comparisons between the proposed algorithm and the existing algorithms establish that our algorithm is robust to noise. A Matlab implementation of our algorithm is available online and free.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Quaternion formulation for the relative camera pose estimation problem. </LI> <LI> Estimating relative camera motion from captured images with high robustness to noise. </LI> <LI> Finding all solutions of a multi-variable polynomial system. </LI> <LI> Comparing state-of-the-art five point camera pose estimation algorithms. </LI> <LI> Vision based robot navigation via position based visual servoing. </LI> </UL> </P>

Cdkn1a deletion improves stem cell function and lifespan of mice with dysfunctional telomeres without accelerating cancer formation

Choudhury, Aaheli Roy,Ju, Zhenyu,Djojosubroto, Meta W,Schienke, Andrea,Lechel, Andre,Schaetzlein, Sonja,Jiang, Hong,Stepczynska, Anna,Wang, Chunfang,Buer, Jan,Lee, Han-Woong,von Zglinicki, Thomas,Gans Nature Pub. Co 2007 Nature genetics Vol.39 No.1

Telomere shortening limits the proliferative lifespan of human cells by activation of DNA damage pathways, including upregulation of the cell cycle inhibitor p21 (encoded by Cdkn1a, also known as Cip1 and Waf1)) (refs. 1–5). Telomere shortening in response to mutation of the gene encoding telomerase is associated with impaired organ maintenance and shortened lifespan in humans and in mice. The in vivo function of p21 in the context of telomere dysfunction is unknown. Here we show that deletion of p21 prolongs the lifespan of telomerase-deficient mice with dysfunctional telomeres. p21 deletion improved hematolymphopoiesis and the maintenance of intestinal epithelia without rescuing telomere function. Moreover, deletion of p21 rescued proliferation of intestinal progenitor cells and improved the repopulation capacity and self-renewal of hematopoietic stem cells from mice with dysfunctional telomeres. In these mice, apoptotic responses remained intact, and p21 deletion did not accelerate chromosomal instability or cancer formation. This study provides experimental evidence that telomere dysfunction induces p21-dependent checkpoints in vivo that can limit longevity at the organismal level.

常用詞“甘”、“甜”歷時演變與興替研究

?玉君(Gan Yeechin),朴敏浚(Park, Min-jun) 중국어문학연구회 2017 중국어문학논집 Vol.0 No.105

It is important to study the diachronic change and replacement of old words by new ones in Chinese etymology as the process does not happen and complete within a short span of time. This paper propose an in-depth study on gan (甘) and tian (甜) by investigating a number of historical documents of various registers from the Pre-Qin to the Ming and Qing dynasties. Based on the diachronic perspective, we conduct a quantitative analysis to show the lexical development and replacement process of gan (甘) and tian (甜) in its original and extended meanings. In the meantime, we also describes usage pattern and competition process of the two words in different periods, by comparing them in terms of usage frequency, semantic expression and syntactic distribution. Because gan (甘) is a polysemy with multiple meanings since the Pre-Qin dynasty, a new word tian (甜) with a single meaning of sweet taste emerged in the Western Han dynasty, which is subsequently commonly used in oral literature in the Wei and Jin dynasties. Afterwards, tian (甜) went into competition with gan (甘) in the Tang and Song dynasties, whose meaning was in turn further extended to psychological and sensory domains in the Ming and Qing dynasties. In modern Chinese, gan (甘) came to only function as a morpheme through semantic bleaching whereas tian (甜) often appeared in sentential structure. The semantic and syntactic functions of the two words remain stable and still in use.

Low Resistance and Transparent Ag/AZO Ohmic Contact to p-GaN

T. Han,T. Wang,X. W. Gan,H. Wu,Y. Shi,C. Liu 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.1

Silver (Ag)/ aluminum-doped zinc oxide (AZO) films were deposited on p-GaN by using electronbeamevaporation. After the annealing process, current -voltage (I-V) measurements were carriedout to determine the characteristic of the contacts. The Ag/AZO films annealed at 600 C werefound to present an ohmic contact behavior. The specific contact resistance was calculated tobe 9.76 × 10−4cm2 and the transmittance was over 80% for visibly light. The atomic forcemicroscope was used to measure the aggregation of Ag grains which may have been the main factorin the formation of the Ag/AZO ohmic contact to p-GaN.

Preventing Intra-hospital Infection and Transmission of Coronavirus Disease 2019 in Health-care Workers

Gan, Wee Hoe,Lim, John Wah,Koh, David Occupational Safety and Health Research Institute 2020 Safety and health at work Vol.11 No.2

Coronavirus disease 2019 poses an occupational health risk to health-care workers. Several thousand health-care workers have already been infected, mainly in China. Preventing intra-hospital transmission of the communicable disease is therefore a priority. Based on the Systems Engineering Initiative for Patient Safety model, the strategies and measures to protect health-care workers in an acute tertiary hospital are described along the domains of work task, technologies and tools, work environmental factors, and organizational conditions. The principle of zero occupational infection remains an achievable goal that all health-care systems need to strive for in the face of a potential pandemic.

Emulsifying Properties of Lecithin Containing Different Fatty Acids Obtained by Immobilized Lecitase Ultra-Catalyzed Reaction

Gan, Lu-Jing,Wang, Xiang-Yu,Yang, Dan,Zhang, Hua,Shin, Jung-Ah,Hong, Soon-Taek,Park, Sang Hyun,Lee, Ki-Teak Wiley (John WileySons) 2014 Journal of the American Oil Chemists' Society Vol.91 No.4

Lecitase Ultra and 6 triacylglycerol lipases (lipases PS, M, AH, AY, R, and AK) were immobilized on Amberlite XAD 7HP and used to catalyze the acidolysis reaction between lecithin and capric acid (C10:0) for comparison. The highest molar incorporation value (51.0 mol%) was observed for the immobilized Lecitase Ultra. Further, immobilized Lecitase Ultra was selected for catalyzing acidolysis between lecithin and fatty acids with different chain lengths (C6:0, C8:0, C10:0, C12:0, and C14:0). After reaction, free fatty acids were removed by SPE and the resultant was called modified lecithin fraction 1 (MLF1). The highest molar incorporation value was obtained for C10:0 (51.0 mol%) at 45 A degrees C with a mole ratio of 10/1 (C10:0/lecithin) for 72 h. After removal of lysophosphatidylcholine by solid-phase extraction from MLF1, the resultant modified lecithin fraction 2 (MLF2) was used to prepare an oil-in-water emulsion. All emulsions prepared with MLF2 exhibited significantly higher emulsion stability (ES) values (16.2-17.7) and smaller particle sizes (d (32) 0.40-0.49 mu m, d (43) 0.75-1.01 mu m) than the emulsion prepared with unmodified lecithin (ES 14.1, d (32) 0.76 mu m, d (43), 1.26 mu m) (P < 0.05). Furthermore, less clarification and droplet aggregation were observed in emulsions prepared with MLF2 than in lecithin-based emulsions. Overall, the MLF2s showed better emulsifying properties than lecithin.

Seafood feast in Dalian, Liaoning Province

Gan Chun 한국콘텐츠학회 2021 한국콘텐츠학회 ICCC 논문집 Vol.2021 No.12