Distinct functions of eosinophils in severe asthma with type 2 phenotype: clinical implications

Youngwoo Choi,심소윤,Hae-Sim Park 대한내과학회 2020 The Korean Journal of Internal Medicine Vol.35 No.4

Asthma is commonly recognized as a heterogeneous condition with a complex pathophysiology. With advances in the development of multiple medications for patients with asthma, most asthma symptoms are well managed. Nevertheless, 5% to 10% of adult asthmatic patients (called severe asthma) are in uncontrolled or partially controlled status despite intensive treatment. Especially, severe eosinophilic asthma is one of the severe asthma phenotypes characterized by eosinophilia in sputum/blood driven by type 2 immune responses. Eosinophils have been widely accepted as a central effector cell in the lungs. Some evidence has demonstrated that persistent eosinophilia in upper and lower airway mucosa contributes to asthma severity by producing various mediators including cytokines, chemokines and granule proteins. Moreover, extracellular traps released from eosinophils have been revealed to enhance type 2 inflammation in patients with severe asthma. These novel molecules have the ability to induce airway inf lammation and hyperresponsiveness through enhancing innate and type 2 immune responses. In this review, we highlight recent insight into the function of eosinophil extracellular traps in patients with severe asthma. In addition, the role of eosinophil extracellular vesicles in severe asthma is also proposed. Finally, current biologics are suggested as a potential strategy for effective management of severe eosinophilic asthma.

A finite element method for elliptic optimal control problem on a non-convex polygon with corner singularities

Choi, Hyung Jun,Choi, Woocheol,Koh, Youngwoo Elsevier 2018 COMPUTERS & MATHEMATICS WITH APPLICATIONS - Vol.75 No.1

<P><B>Abstract</B></P> <P>In this paper, we study a finite element method overcoming corner singularities for elliptic optimal control problem posed on a polygon. Based on a corner singularity decomposition of singular solution for the associated elliptic system, we derive an extraction formula for coefficients of singular parts, called stress intensity factors, and introduce a finite element discretization for regular parts of the solution pair. Furthermore, we analyze the finite element solutions in <SUP> L 2 </SUP> and <SUP> H 1 </SUP> norms. By numerical experiments, we confirm the efficiency and reliability of the proposed method.</P>

Comparative Analysis of the Spatial Structure of Apartment Unit Plans in Asia - Apartments in Korea, Vietnam, and Kazakhstan -

Choi, Jaepil,Kim, Youngwoo,Kang, Junekyung,Choi, Youngjun Architectural Institute of Japan 2014 JOURNAL OF ASIAN ARCHITECTURE AND BUILDING ENGINEE Vol.13 No.3

<P> Though apartments are often criticized for their homogeneous nature, they are being actively adopted as an efficient method of providing houses for developing countries. In this paper, the authors argue whether such phenomenon can be seen simply as cultural identity giving in to internationalism. That is, apartments can indeed reflect locality within their spatial structure. To support this argument, apartment units from Korea, Vietnam, and Kazakhstan, three countries from dramatically different climate zones and cultural backgrounds, are analyzed. In doing so, Space Syntax, a quantitative analysis method widely used to interpret the cultural aspects embedded into a spatial structure is utilized. Each country's apartment units had different functions at the topological center, which should not be seen as a mere coincidence since they were consistent with the spatial characteristic found in their respective traditional houses. Therefore, it can be said that apartments, in their unit plans, do reflect locality, a direct contradiction to the general belief. </P>

Chemical Bath Deposition of Stoichiometric CdSe Quantum Dots for Efficient Quantum-Dot-Sensitized Solar Cell Application

Choi, Youngwoo,Seol, Minsu,Kim, Wooseok,Yong, Kijung American Chemical Society 2014 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.118 No.11

<P>Cadmium selenide (CdSe) quantum dots (QDs) have been prepared by suppressing the formation of an amorphous selenium oxide (SeO<SUB>2</SUB>) layer on the surface of CdSe QDs. The precursor ratio for the chemical bath deposition was optimized to minimize the SeO<SUB>2</SUB> layer growth and develop high-efficiency CdSe QDs for quantum-dot-sensitized solar cell (QDSSC) applications. The morphologies and optical and electrical properties of the CdSe QDs were investigated, and the growth mechanism was also proposed for the CdSe and SeO<SUB>2</SUB> layer formation. Furthermore, electrochemical impedance spectroscopy results indicated that the SeO<SUB>2</SUB> layer reduced the recombination resistance of photogenerated electron–hole pairs, thus degrading the cell efficiency. Therefore, a QDSSC based on an optimized CdSe/CdS/ZnO nanowire photoanode, polysulfide electrolyte, and Au counter electrode can enhance the power conversion efficiency to 4.8% under AM 1.5 G one-sun illumination.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2014/jpccck.2014.118.issue-11/jp411221q/production/images/medium/jp-2013-11221q_0011.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp411221q'>ACS Electronic Supporting Info</A></P>

Solar-driven hydrogen evolution using a CuInS2/CdS/ZnO heterostructure nanowire array as an efficient photoanode.

Choi, Youngwoo,Beak, Minki,Yong, Kijung RSC Pub 2014 Nanoscale Vol.6 No.15

<P>Photoanodes prepared using CuInS2/CdS/ZnO nanowires were fabricated by a solution-based process for constructing a photo-driven hydrogen generation system. For efficient light harvesting and photoexcited charge collection, ZnO nanowire (NW) photoanode arrays were co-sensitized with CdS and CuInS2 (CIS). A CdS layer was deposited on the ZnO NW via successive ion layer adsorption and reaction (SILAR), and the CIS layer was prepared by depositing a molecular precursor solution onto the CdS/ZnO NW. The generated anodic photocurrent was increased with the subsequent deposition of the CIS and CdS layers. Ultraviolet photoelectron spectroscopy analysis revealed cascade type-II band alignments for the CIS/CdS/ZnO NW photoanodes, which enabled efficient electron collection. Our heterostructure photoelectrode has generated a greatly improved photocurrent density of 13.8 mA cm(-2) at 0.3 V vs. SCE under 1 sun illumination.</P>

Predictive model for the flight period of an ambrosia beetle, Platypus koryoensis (Coleoptera: Platypodinae)

Youngwoo Nam,Won IL Choi,Dae-Sung Won,Jong-Kuk Kim,Sang-Hyun Koh,Jung-Su Lee,Kyung-Hee Kim 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.10

An ambrosia beetle, Platypus koryoensis, is a vector of Raffaelea quercimongolicae that is known to cause Korean Oak Wilt (KOW), one of the serious threats to forest healthy in Korea. To manage P. koryoensis properly, it is necessary to clarify flight period of the adult. This experiment was conducted to elucidate the relationship between temperature and the flight period based on field observation in three forests consisted of Quercus mongolica from 2007 to 2009 except winter season. Date of flight period for 50% (FP50) was estimated by the cumulative Weibull distribution model based on cumulative proportion of the adult density and air temperature. Relationship between site temperature and the date of FP50 of P. koryoensis was the most significant when temperatures below 6.5℃ were excluded, suggesting lower threshold temperature for the flight period based on the site temperature. The pooling cumulative proportion of flight period against degree days was well described by the degree-day model, which has explanatory power for the 89% of year and site variation in the flight period and predicted accurately the flight pattern in 2011.

Which Factors Associated With Activated Eosinophils Contribute to the Pathogenesis of Aspirin-Exacerbated Respiratory Disease?

Choi, Youngwoo,Lee, Youngsoo,Park, Hae-Sim The Korean Academy of Asthma, Allergy and Clinical 2019 Allergy, Asthma & Immunology Research Vol.11 No.3

<P>Eosinophils have long been recognized as a central effector cell in the lungs of asthmatic patients. They contribute to airway inflammation and remodeling through releasing several molecules such as cytokines, granule proteins, lipid mediators and extracellular traps/vesicles. Repeated evidence reveals that intense eosinophil infiltration in upper and lower airway mucosae contributes to the pathogenesis of aspirin-exacerbated respiratory disease (AERD). Persistent eosinophilia is found to be associated with type 2 immune responses, cysteinyl leukotriene overproduction and eosinophil-epithelium interactions. This review highlights recent findings about key mechanisms of eosinophil activation in the airway inflammation of AERD. In addition, current biologics (targeting type 2 immune responses) were suggested to control eosinophilic inflammation for AERD patients.</P>

Radio Frequency Based Emergency Exit Node Technology

Choi, Youngwoo,Kim, Dong Kyoo,Kang, Do Wook,Choi, Wan Sik The Institute of Positioning 2013 Journal of Positioning, Navigation, and Timing Vol.2 No.1

This paper introduces an indoor sensor fusion wireless communication device which provides the Location Based Service (LBS) using fire prevention facility. The proposed system can provide information in real time by optimizing the hardware of Wi-Fi technology. The proposed system can be applied to a fire prevention facility (i.e., emergency exit) and provide information such as escape way, emergency exit location, and accident alarm to smart phone users, dedicated terminal holders, or other related organizations including guardians, which makes them respond instantly with lifesaving, emergency mobilization, etc. Also, the proposed system can be used as a composite fire detection sensor node with additional fire and motion detect sensors.

INFINITUDE OF MINIMALLY SUPPORTED TOTALLY INTERPOLATING BIORTHOGONAL MULTIWAVELET SYSTEMS WITH LOW APPROXIMATION ORDERS

Choi, Youngwoo,Jung, Jaewon The Kangwon-Kyungki Mathematical Society 2013 한국수학논문집 Vol.21 No.3

By analyzing one-parameter families of totally interpolating multiwavelet systems of minimal total length with low approximation orders, whose explicit formulas were obtained with the aid of well-known relations of filters, we demonstrate the infinitude of such systems.

Occurrence Characteristics Analysis of Pine Wilt Disease: A case study on Andong-si and Yeongdeok-gun, Korea

Youngwoo Nam,Won Il Choi,Hye Jung Song,Kyu Wha Kim 한국응용곤충학회 2015 한국응용곤충학회 학술대회논문집 Vol.2015 No.10

This study was conducted to examine the occurrence characteristics of pine trees infected by pine wood nematode in Gyeongsangbuk-do, Korea. Based on the GPS coordinate data of the infected trees at Yeongdeok-gun from 2013 to 2014 and at Andong-si in 2014, nearest neighbor analysis was conducted to analyze nearest distance between the infected trees. And the influence of geographical factors such as altitude, slope, and the distance from the road on the position of infected trees were identified. Our results showed that over 60% of the newly infected trees were found within 50m of the trees infected in previous year. Over 70% of infected trees occurred below 100m altitude in Yoeongdeok-gun whereas less 32% of total pine trees distributed below the altitude. 98% of the infected trees and 74% of total pine trees in Andong-si were found between 150 and 300m altitude, and altitudinal distribution of the infected trees was similar to that of pine forests. Only less 5% of infected trees found in the forests located below 5 degree of slope in Yeongdeok-gun whereas 18% of total pine trees existed in the areas. Over 50% of infected trees in the forests located from 10 to 20 degree of slope, and 47% of total pine trees were found in the forests located from 5 to 15 degree of slope. Most infected trees and total pine trees were found in the forests located below 15 degree of slope in Andong-si. Over 80% of the infected trees occurred within 1km of road in both study areas.