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Universality, scaling and collapse in supercritical fluids [article]

Min Young Ha, Tae Jun Yoon, Tsvi Tlusty, YongSeok Jho, Won Bo Lee
2019 arXiv   pre-print
The Supercritical Fluid (SCF) is known to exhibit salient dynamic and thermodynamic crossovers and inhomogeneous molecular distribution. But the question as to what basic physics underlies these microscopic and macroscopic anomalies remains open. Here, using an order parameter extracted by machine learning, the fraction of gas-like (or liquid-like) molecules, we find simplicity and universality in SCF: First, all isotherms of a given fluid collapse onto a single master curve described by a
more » ... ng relation. The observed power law holds from the high-temperature and pressure regime down to the critical point where it diverges. Second, phase diagrams of different compounds collapse onto their master curves by the same scaling exponent, thereby demonstrating a putative law of corresponding supercritical states in simple fluids. The reported results support a model of the SCF as a mixture of two interchangeable microstates, whose spatiotemporal dynamics gives rise to unique macroscopic properties.
arXiv:1902.08360v1 fatcat:aanweabg2rh6tcxbx7zxnyrbbu

Novel buried inverse-trapezoidal micropattern for dual-sided light extracting backlight unit

Gun-Wook Yoon, Hyeon-Don Kim, Jeongho Yeon, Jun-Bo Yoon
2014 Optics Express  
We devised a novel buried inverse-trapezoidal (BIT) micropattern that can enable light extracting to both front and back sides of the backlight unit (BLU). The proposed BLU comprised of only a singlesheet light-guide plate (LGP) having the BIT micropatterns only on the top surface of the LGP. The proposed BLU shows normal directional light emitting characteristics to both the front and back sides of the LGP and successfully acts as a planer light source for a dual-sided LCD. The proposed BLU
more » ... the potential to dramatically reduce the thickness, weight and cost of the dual-sided LCD thanks to its single-sheet nature.
doi:10.1364/oe.22.032440 pmid:25607206 fatcat:3se4vjkztjcijdtsiaegqum46u

A high fill-factor infrared bolometer using micromachined multilevel electrothermal structures

Hyung-Kew Lee, Jun-Bo Yoon, Euisik Yoon, Sang-Baek Ju, Yoon-Joong Yong, Wook Lee, Sang-Gook Kim
1999 IEEE Transactions on Electron Devices  
Yoon, and E. Yoon are with the Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, Taejon 305-701, Korea (e-mail: esyoon@ee.kaist.ac.kr). S.-B. Ju, Y.-J.  ... 
doi:10.1109/16.772496 fatcat:62cudtajlrg4pegx5urzwcrqiy

A new monolithic microbiosensor for whole blood analysis

Joon-Ho Kim, Byoung-Gyun Kim, Jun-Bo Yoon, Euisik Yoon, Chul-Hi Han
2002 Sensors and Actuators A-Physical  
A new microbiosensor has been proposed and fabricated for the measurement of glucose concentration in whole blood. The proposed microbiosensor has been monolithically integrated with enzymatic metal microelectrode array in a micromachined chamber attached to a microsyringe. The fabricated microbiosensor has a high sensitivity of 470 nA/cm 2 mM for detecting glucose levels in a wide linear range of 0±50 mM in potassium phosphate buffer solution (pH 7.0). #
doi:10.1016/s0924-4247(01)00721-x fatcat:mzumm2iexjbt3dzqbgq7ntv3xu

Fully integrated low phase-noise VCOs with on-chip MEMS inductors

Eun-Chul Park, Yun-Seok Choi, Jun-Bo Yoon, Songcheol Hong, E. Yoon
2003 IEEE transactions on microwave theory and techniques  
We present fully integrated high-performance voltage-controlled oscillators (VCOs) with on-chip microelectromechanical system (MEMS) inductors for the first time. MEMS inductors have been realized from the unique CMOS-compatible MEMS process that we have developed to provide suspended thick metal structures for high-quality ( ) factors. Fully integrated CMOS VCOs have been fabricated by monolithically integrating these MEMS inductors on the top of the CMOS active circuits realized by the TSMC
more » ... 18m mixed-mode CMOS process. Low phase noise has been achieved as 124 and 117 dBc/Hz at 300-kHz offset from carrier frequencies of 1 and 2.6 GHz, respectively, in the fabricated single-chip VCOs.
doi:10.1109/tmtt.2002.806510 fatcat:4ic7gjjkujantlah6kwdf4lzy4

CMOS-compatible surface-micromachined suspended-spiral inductors for multi-GHz silicon RF ICs

Jun-Bo Yoon, Yun-Seok Choi, Byeong-Il Kim, Yunseong Eo, Euisik Yoon
2002 IEEE Electron Device Letters  
Yoon, Y.-S. Choi, B.-I. Kim, and E.  ...  Yoon are with the Division of Electrical Engineering, Department of Electrical Engineering and Computer Science, Korea Advanced Institute of Science and Technology (KAIST), Taejon 305-701, Korea (e-mail  ... 
doi:10.1109/led.2002.803767 fatcat:zcx4dfc6zjendcup4pcfyqfznq

Surface micromachined solenoid on-Si and on-glass inductors for RF applications

Jun-Bo Yoon, Bon-Kee Kim, Chul-Hi Han, Euisik Yoon, Choong-Ki Kim
1999 IEEE Electron Device Letters  
RF performance of surface micromachined solenoid on-chip inductors fabricated on a standard silicon substrate (10 1 cm) has been investigated and the results are compared with the same inductors on glass. The solenoid inductor on Si with a 15-m thick insulating layer achieves peak quality (Q0) factor of 16.7 at 2.4 GHz with inductance of 2.67 nH. This peak Q-factor is about two-thirds of that of the same inductor fabricated on glass. The highest performance has been obtained from the
more » ... tched on-glass inductor, which shows inductance of 2.3 nH, peak Q-factor of 25.1 at 8.4 GHz, and spatial inductance density of 30 nH/mm 2 . Both on-Si and on-glass inductors have been modeled by lumped circuits, and the geometrical dependence of the inductance and Q-factor have been investigated as well. Index Terms-High Q, integrated inductor, micromachining, on-chip solenoid inductor, RF MEMS.
doi:10.1109/55.784461 fatcat:gqwjq6ddwzgtld3txhdjmzrx7i

Voltage-Controlled $C{-}V$ Response Tuning in a Parallel Plate MEMS Variable Capacitor

Chang-Hoon Han, Dong-Hoon Choi, Hyun-Ho Yang, Yong-Hoon Yoon, Jun-Bo Yoon
2013 Journal of microelectromechanical systems  
In a conventional parallel plate MEMS variable capacitor, the capacitance versus voltage response (C-V response) has been deterministic. In this work, the C-V response is tuned versatilely through the application of a control voltage to an additional electrode in order that the initial gap between the parallel capacitor plates is set by the control voltage. Then, the capacitor plates are lifted (capacitance decreases) as the actuation voltage applied to the levering actuator increases. In this
more » ... anner, the shape of the C-V response can be controlled even after the device is fabricated. At a zero control voltage, the fabricated MEMS variable capacitor exhibited a convex shape in the C-V response (i.e. the capacitance decreases slowly in the low actuation voltage region and rapidly in the high actuation voltage region). When 3 V was applied to the control voltage, the capacitor exhibited an almost linear C-V response with a linearity factor of 0.999. At 5 V of control voltage, the C-V response changed to a relatively concave shape (i.e. the capacitance decreases rapidly in the low actuation voltage region and slowly in the high actuation voltage region). The capacitance tuning ratio of the fabricated device exceeded 120% at all control voltages. The proposed C-V response tuning capability is vital and amenable to various circuit demands. [ 2012-0235] Index Terms-Capacitance tuning ratio, capacitance versus voltage response (C-V response) tuning, levering actuator, linearity, microelectromechanical system (MEMS), variable capacitor. 1057-7157 c 2013 IEEE
doi:10.1109/jmems.2013.2257987 fatcat:yseuqsfrvzbtjbdqnmuyidocum

The First Korean Family with Hemoglobin-M Milwaukee-2 Leading to Hereditary Methemoglobinemia

Dae Sung Kim, Hee Jo Baek, Bo Ram Kim, Bo Ae Yoon, Jun Hyung Lee, Hoon Kook
2020 Yonsei medical journal  
Hemoglobin M (HbM) is a group of abnormal hemoglobin variants that form methemoglobin, which leads to cyanosis and hemolytic anemia. HbM-Milwaukee-2 is a rare variant caused by the point mutation CAC>TAC on codon 93 of the hemoglobin subunit beta (HBB) gene, resulting in the replacement of histidine by tyrosine. We here report the first Korean family with HbM-Milwaukee-2, whose diagnosis was confirmed by gene sequencing. A high index of suspicion for this rare Hb variant is necessary in a
more » ... t presenting with cyanosis since childhood, along with methemoglobinemia and a family history of cyanosis.
doi:10.3349/ymj.2020.61.12.1064 pmid:33251782 pmcid:PMC7700874 fatcat:eu6ojsingreohds3zlb6ffaona

Fraxin Prevents Chemically Induced Hepatotoxicity by Reducing Oxidative Stress

Bo Chang, Young Jung, Chi-Su Yoon, Jun Oh, Jae Hong, Youn-Chul Kim, Sung Kim
2017 Molecules  
Fraxin isolated from Acer tegmentosum is reported to exert potent anti-oxidative stress action. However, pharmacological activities of fraxin remain to be elucidated. This study investigated the potential hepatoprotective effects of fraxin and the underlying signaling mechanism involved. Treatment with fraxin significantly lowered the serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in a CCl 4 -induced hepatotoxicity rat model. In the fraxin-treated group,
more » ... athione (GSH) significantly increased, while the malondialdehyde (MDA) in the liver significantly decreased. Fraxin also showed radical-scavenging activity. Furthermore, it significantly reduced the t-BHP-induced cytotoxicity and production of reactive oxygen species (ROS) in Hep G2. Fraxin protected Hep G2 cells through Nrf2 pathway-dependent HO-1 expression. The results of this study indicate that fraxin shows potent hepatoprotective effects in vitro and in vivo, presumably through direct antioxidant activity and the Nrf2-mediated antioxidant enzyme system.
doi:10.3390/molecules22040587 pmid:28383514 fatcat:kjcddyn6gbarvgioo5qo4koy5i

Deep-Plane Lipoabdominoplasty in East Asians

June-Kyu Kim, Jun-Young Jang, Yoon Gi Hong, Hyung Bo Sim, Sang Hoon Sun
2016 Archives of Plastic Surgery  
The objective of this study was to develop a new surgical technique by combining traditional abdominoplasty with liposuction. This combination of operations permits simpler and more accurate management of various abdominal deformities. In lipoabdominoplasty, the combination of techniques is of paramount concern. Herein, we introduce a new combination of liposuction and abdominoplasty using deep-plane flap sliding to maximize the benefits of both techniques. Methods Deep-plane lipoabdominoplasty
more » ... was performed in 143 patients between January 2007 and May 2014. We applied extensive liposuction on the entire abdomen followed by a sliding flap through the deep plane after repairing the diastasis recti. The abdominal wound closure was completed with repair of Scarpa's fascia. Results The average amount of liposuction aspirate was 1,400 mL (700-3,100 mL), and the size of the average excised skin ellipse was 21.78 × 12.81 cm (from 15 × 10 to 25 × 15 cm). There were no major complications such as deep-vein thrombosis or pulmonary embolism. We encountered 22 cases of minor complications: one wound infection, one case of skin necrosis, two cases of undercorrection, nine hypertrophic scars, and nine seromas. These complications were solved by conservative management or simple revision. Conclusions The use of deep-plane lipoabdominoplasty can correct abdominal deformities more effectively and with fewer complications than traditional abdominoplasty.
doi:10.5999/aps.2016.43.4.352 pmid:27462568 pmcid:PMC4959978 fatcat:jcc3mw2ehjaa3kb6mi5yju3hb4

Prevalence of BRCA1 and BRCA2 Mutations in Korean Breast Cancer Patients

Sei Hyun Ahn, Ui Kang Hwang, Beom Seok Kwak, Ho Sung Yoon, Bo Kyung Ku, Hee Jun Kang, Ji Su Kim, Byung Kyun Ko, Chang Dae Ko, Kyung Sik Yoon, Dae-Yeon Cho, Jun Suk Kim (+1 others)
2004 Journal of Korean medical science  
doi:10.3346/jkms.2004.19.2.269 pmid:15082902 pmcid:PMC2822310 fatcat:ewvgmsrp4jdp5aydd3levml3we

A Case of Cerebellar Infarction with Renal Artery Stenosis

Jun-Beom Lee, Seong-Bo Yoon, Won-Sik Cho, Ki-Hoon Baek
2012 Korean Journal of Stroke  
Renal artery stenosis (RAS) is defined as a narrowing of main renal artery or its major branches over 50%, and can be the cause of pulmonary edema, renal failure, malignant hypertension and cerebrovascular diseases. The renin-angiotensin-aldosterone system works as a key role. In this paper, we report a case of a 53 year-old patient with left middle cerebellar peduncle infarction, who showed malignant hypertension and RAS. The RAS was diagnosed by renal artery computed tomography angiography
more » ... treated with renal artery angioplasty, stenting and antihypertensive medication. In a young patient with ischemic stroke who has refractory hypertension against antihypertensive medications, RAS should be suspected and evaluated. (Korean J Stroke 2012;14:82-85) KEY WORDS: Cerebral infarction, Renal artery stenosis, Renovascular hypertension, Renin-angiontensin-aldosterone system, Stents Korean J Stroke 2012;14(2):82-85 http://dx. CASE REPORT
doi:10.5853/kjs.2012.14.2.82 fatcat:cgqovnzrpvb2xgejhbbnotvp5q

Epsilon-Globin HBE1 Enhances Radiotherapy Resistance by Down-Regulating BCL11A in Colorectal Cancer Cells

Sang Yoon Park, Seon-Jin Lee, Hee Jun Cho, Jong-Tae Kim, Hyang Ran Yoon, Kyung Ho Lee, Bo Yeon Kim, Younghee Lee, Hee Gu Lee
2019 Cancers  
Moreover, HBE1 overexpression was found to attenuate radiation-induced endoplasmic reticulum stress and apoptosis via an inositol-requiring enzyme 1(IRE1)—Jun amino-terminal kinase (JNK) signaling pathway  ...  Figure 4 . 4 Enrichment of HBE1 levels decreases the radiation-induced activation of Jun amino-terminal kinase (JNK) and endoplasmic reticulum (ER) stress.  ...  Figure 4 . 4 Enrichment of HBE1 levels decreases the radiation-induced activation of Jun amino-terminal kinase (JNK) and endoplasmic reticulum (ER) stress.  ... 
doi:10.3390/cancers11040498 pmid:30965648 pmcid:PMC6521047 fatcat:fzcfa3a2czbnbftahpj7gnb7ke

Influence of comorbidities on functional outcomes in patients with surgically treated fragility hip fractures: a retrospective cohort study

Soo Hoon Yoon, Bo Ryun Kim, Sang Yoon Lee, Jaewon Beom, Jun Hwan Choi, Jae-Young Lim
2021 BMC Geriatrics  
The incidence and number of fragility hip fractures are gradually increasing, resulting in a wide consumption of medical resources. Various factors affecting functional recovery in patients with fragility hip fractures are known, and comorbid diseases are one of them. The purpose of this study is to determine the effect of comorbidities on functional outcomes in patients surgically treated for fragility hip fractures, thereby contributing to the efficient distribution of medical resources. This
more » ... was a retrospective cohort study performed in the three tertiary rehabilitation facilities. A total of 211 patients (50 men and 161 women; average age 81.6 ± 6.7 years) who had undergone surgery for fragility hip fractures were followed up from immediately after transfer to the Department of Rehabilitation Medicine to 6 months postoperatively. Comorbidities referred to a summary of the following conditions: hypertension, diabetes mellitus, chronic liver disease, dementia, cerebrovascular accident, and osteoporosis. Functional outcomes included Koval's grade, Functional Ambulatory Category (FAC), Functional Independence Measure (FIM)-locomotion, Modified Rivermead Mobility Index, Berg Balance Scale (BBS), 4-Meter Walking speed Test (4MWT), the Korean version of the Mini-Mental State Examination(K-MMSE), Geriatric Depression Scale (GDS), EuroQol Five-Dimension (EQ-5D) questionnaire, the Korean version of the Modified Barthel Index (K-MBI), the Korean version of the Instrumental Activities of Daily Living (K-IADL), and Korean version of Fatigue, Resistance, Ambulation, Illnesses, and Loss of weight scale (K-FRAIL). For all tests, each patient was assessed immediately after transfer and 6 months post-surgery. Multivariate linear regression analyses adjusted for age, sex, the initial variable of the functional outcomes, and comorbidities revealed that dementia had a significant negative impact on Koval's grade and K-FRAIL 6 months postoperatively. Diabetes mellitus had a significant negative impact on the FAC, GDS, EQ-5D, K-IADL, and K-FRAIL 6 months postoperatively. Patients with osteoporosis showed a significant negative outcome of FIM-locomotion 6 months postoperatively. A cerebrovascular accident revealed a significant negative impact on the BBS 6 months postoperatively. In addition, hypertension led to significantly less favorable outcomes of the K-FRAIL 6 months postoperatively. This study confirmed that comorbidities, particularly dementia and diabetes mellitus, significantly influence functional outcomes 6 months after fragility hip fracture surgeries.
doi:10.1186/s12877-021-02227-5 pmid:33910513 fatcat:2pm34jjztja2xhmv2wgbojenz4
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