DSC and physical property analysis by mixed ratio of mixed vegetable oil and temperature

Youngjae Cho,Honggyun Kim,Eunji Kwak,Junggyu Lee,Junhwan Bae,SangYoon Lee,Yoon Jung Lee,HeeJeong Choi,Dong Hyeon Park,JingJing Bai,Mi-Jung Choi 한국산업식품공학회 2017 학술대회 및 심포지엄 Vol.2017 No.11

In this study, we investigated the change of physical properties associated with the temperature of vegetable mixed oil and fat in order to produce vegetable oil and fat suitable for plant meat production. The canola oil and coconut oil were mixed at various weight ratios, and the phase change temperatures by the ratio of two oils were measured using the differential scanning calorimetry (DSC). Storage modulus (G'), loss modulus (G") and viscosity were measured using a rheometer at 20-40°C and 0.4 Hz-100 Hz. Storage modulus (G') at constant frequency (10 Hz) was measured in a continuous section of 10-50°C. As the coconut oil content increased, the peak of the melting point moved to the lower side. The viscosity was higher in order of canola oil, mixed oil, and coconut oil, and the viscosity showed a tendency to decrease as the temperature increased. In the liquid state, it showed a tendency to increase after the value of storage modulus (G') and loss modulus (G") decreased from 0.634 Hz-1 Hz. The conversion time point of storage modulus (G') of continuous temperature change is consistent with the melting point temperature of DSC, as the passed start at 10°C, storage modulus (G') increased with an exception of canola oil. Using these results, we will pursue to produce a mixed plant oil applicable to the production of vegetable meat.

Characteristics and distribution of terpenes in South Korean forests

Lee, Jaeseok,Cho, Kyoung Sang,Jeon, Youngjae,Kim, Ji Beom,Lim, Young-ran,Lee, Kyungho,Lee, Im-Soon The Ecological Society of Korea 2017 Journal of Ecology and Environment Vol.41 No.5

The importance of forests continues to increase throughout the world, and one of the reasons is that a forest is a major place to emit terpenes, which have been reported to be beneficial to human health. In South Korea, forests occupy about 64% of the total land area and consist mainly of pine and oak trees. Since only a limited number of forests have been analyzed to date, a comprehensive understanding of terpenes emitted from regional forests remains in its infancy in Korea. Here, to gain insights into terpenes from regional forests located in South Korea, we review the characteristics of Korean forests and recent studies on major terpenes emitted from regional forests as well as from native trees dominant in South Korea. We also discuss meteorological factors that affect the terpene emissions in Korean forests. In conclusion, 18 types of terpenes were detected in Korean forests and their compositions in different forests are largely dependent on the dominant plant species in the forest. Moreover, terpene emissions in Korean forests are affected by various environmental factors, including temperature, amount and duration of daylight, season, and age of trees. To improve the understanding of the characteristics of terpene distribution, more studies are required on the terpene production of Korean forests in various regions.

Surface Viscoelasticity of an Organic Interlayer Affects the Crystalline Nanostructure of an Organic Semiconductor and Its Electrical Performance

Lee, Hwa Sung,Kang, Moon Sung,Kang, Sung Kyung,Kim, Beom Joon,Yoo, Youngjae,Lim, Ho Sun,Um, Soong Ho,Ryu, Du Yeol,Lee, Dong Ryeol,Cho, Jeong Ho American Chemical Society 2012 The Journal of Physical Chemistry Part C Vol.116 No.41

<P>We demonstrated that the viscoelasticity of a dielectric surface affected the overlying pentacene crystalline nanostructures and the electrical performances of pentacene-based field-effect transistors (FETs). The surface viscoelasticities of the gate dielectrics were systematically controlled by varying the polymer chain lengths of polystyrene brushes (<I>b</I>-PSs) and the substrate temperature during pentacene deposition. The <I>b</I>-PSs were chosen as a model surface because the glass–liquid transition affected neither the surface energy nor the surface roughness. Moreover, the glass–liquid transition temperature increased with increasing <I>b</I>-PS chain length. The liquid-like <I>b</I>-PS chains disturbed the surface arrangement of the pentacene molecules, which reduced the organization of the crystalline structures, yielding smaller grains during the early stages of pentacene growth. The dramatic changes in the film morphology and crystalline nanostructures above the <I>b</I>-PS glass–liquid transition resulted in noticeable changes in the OFET performance. The systematic investigation of the dielectric surface viscoelasticity presented here provides a significant step toward optimizing the nanostructures of organic semiconductors, and thereby, the device performance, by engineering the interfaces in the OFETs.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2012/jpccck.2012.116.issue-41/jp305820r/production/images/medium/jp-2012-05820r_0007.gif'></P>

Pressure Induced Structural Changes of Proteins Affecting the Ice Nucleation Temperature of Pork Loins

Youngjae Cho,Eun-Jung Lee,Jiseon Lee,SangYoon Lee,Young-Chan Yun,Geun-Pyo Hong 한국축산식품학회 2019 한국축산식품학회지 Vol.39 No.6

This study investigated the effects of pressure-mediated protein changes on the ice nucleation temperature of pork loins. To variate chemical state of meat proteins, pork loin was pressurized at varying pressure levels (100–500 MPa) for 3 min, and moisture content, expressible moisture (EM) and differential scanning calorimetry (DSC) were analyzed. Although, all treatments showed similar moisture content, EM and degree of protein unfolding of pork loin showed different features as of 300 MPa. At moderate pressure treatments (100–200 MPa), all protein fractions were detected in DSC experiments, and pork loin had lower EM than control (p<0.05). Meanwhile, myosin and actin of pork loin treated at greater than 300 MPa were completely unfolded, and the treatments showed high EM compared to control (p<0.05). Unfolding of meat proteins was a factor suppressing ice nucleation, and the ice nucleation temperature tended to decrease with increasing applied pressure level. The ice nucleation characteristics of pressurized pork loin exhibited a potential application in freezing storage of pressurized meat with less tissue damage comparing to freeze fresh meat, and further exploration regarding the quality change after freezing of fresh and pressurized meat was warranted.

A STUDY ON A FIRE-ALARM SYSTEM USING ZIGBEE

YoungJae Lee,JinHo Park,ChoongWon Chang,MinSoo Jung 한국멀티미디어학회 2007 한국멀티미디어학회 국제학술대회 Vol.2007 No.-

We designed a ubiquitous fire alarm system integrate with ZigBee of local area wireless communication technology. If we realize the foundation of this technology, in addition to the specialized regions, we can also realize the movable fire alarm system. In some sensitive places such as the movable ignition depository. the sensitive depository of chemical materials and so on. fire cannot be happened absolutely, if we set the movable fire alarm, the maximal effectiveness will be displayed.

Correlation between caudal pulmonary artery diameter to body surface area ratio and echocardiography-estimated systolic pulmonary arterial pressure in dogs

Youngjae Lee,Wooshin Choi,Donghoon Lee,장진화,Ji-Houn Kang,Ji-hye Choi,Dongwoo Chang 대한수의학회 2016 Journal of Veterinary Science Vol.17 No.2

Caudal pulmonary artery diameter (CPAD) to body surface area (BSA) ratios were measured in ventrodorsal thoracic radiographs to assess the correlation between CPAD to BSA ratios and systolic pulmonary arterial pressure (PAP) in dogs. Thoracic radiographs of 44 dogs with systolic pulmonary arterial hypertension (PAH) and 55 normal dogs were evaluated. Systolic PAP was estimated by Doppler echocardiography. CPADs were measured at their largest point at the level of tracheal bifurcation on ventrodorsal radiographs. Both right and left CPAD to BSA ratios were significantly higher in the PAH group than in the normal group (p < 0.0001). Linear regression analysis showed positive associations between PAP and right and left CPAD to BSA ratio (right, p = 0.0230; left, p = 0.0012). The receiver operating characteristic curve analysis revealed that the CPAD to BSA ratio had moderate diagnostic accuracy for detecting PAH. The operating point, sensitivity, specificity, and area under the curve were 28.35, 81.40%, 81.82%, and 0.870; respectively, for the right side and 26.92, 80.00%, 66.67%, and 0.822, respectively, for the left. The significant correlation of CPAD to BSA ratio with echocardiography-estimated systolic PAP supports its use in identifying PAH on survey thoracic radiographs in dogs.

Phase transfer-driven rapid and complete ligand exchange for molecular assembly of phospholipid bilayers on aqueous gold nanocrystals

Lee, Youngjae,Jang, Jungwoo,Yoon, Jinho,Choi, Jeong-Woo,Choi, Inhee,Kang, Taewook The Royal Society of Chemistry 2019 Chemical communications Vol.55 No.22

<P>A phase transfer-mediated ligand exchange method is developed for highly selective and rapid synthesis of colloidal phospholipid bilayer-coated gold nanocrystals. The complete replacement of strongly bound surface ligands such as cetyltrimethylammonium bromide (CTAB) and citrate by phospholipid bilayer can be quickly achieved by water-chloroform phase transfer.</P>

Clinical influences of anticentromere antibody on primary Sjögren’s syndrome in a prospective Korean cohort

( Youngjae Park ),( Jennifer Lee ),( Jung Hee Koh ),( Jung Yoon Choe ),( Yoon-kyoung Sung ),( Shin-seok Lee ),( Ji-min Kim ),( Sung-hwan Park ),( Seung-ki Kwok ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.6

Background/Aims: This study was performed to clarify influences of anticentromere antibody (ACA) on clinical phenotypes of primary Sjögren’s syndrome (pSS) patients in Korea. Methods: We assessed 318 patients who met the 2016 American College of Rheumatology/European League Against Rheumatism classification criteria for pSS. All patients were selected from the Korean Initiative of primary Sjögren’s Syndrome (KISS), a prospective cohort. Among them, 53 patients were positive for ACA, while another 265 patients were not. We compared various clinical data including demographic features, extra-glandular manifestations (EGMs), clinical indices, and laboratory values available from the KISS database between the two groups. Results: Patients in the ACA-positive pSS group were older (p = 0.042), and had higher xerostomia inventory scores (p = 0.040), whereas glandular dysfunction represented with Schirmer I test was more severe in the ACA-negative group. More frequent Raynaud’s phenomenon and liver involvement (both p < 0.001) and less articular involvement (p = 0.037) were observed among the EGMs in the ACA-positive group. Less frequency of leukopenia (p = 0.021), rheumatoid factor (p < 0.001), anti-Ro/SSA antibody positivity (p < 0.001), and hypergammaglobulinemia (p = 0.006), as well as higher positivity rates of anti-nuclear antibody and anti-topoisomerase antibody (p < 0.001 and p = 0.006, respectively) were found in the laboratory data in the ACA-positive pSS group. Conclusions: Considering distinct phenotypes in hematological and serological features and EGMs, we should monitor the occurrence of these clinical features among pSS patients with ACA in caution.

Lithography-Free Fabrication of Large Area Subwavelength Antireflection Structures Using Thermally Dewetted Pt/Pd Alloy Etch Mask

Lee, Youngjae,Koh, Kisik,Na, Hyungjoo,Kim, Kwanoh,Kang, Jeong-Jin,Kim, Jongbaeg Springer 2009 NANOSCALE RESEARCH LETTERS Vol.4 No.4

<P>We have demonstrated lithography-free, simple, and large area fabrication method for subwavelength antireflection structures (SAS) to achieve low reflectance of silicon (Si) surface. Thin film of Pt/Pd alloy on a Si substrate is melted and agglomerated into hemispheric nanodots by thermal dewetting process, and the array of the nanodots is used as etch mask for reactive ion etching (RIE) to form SAS on the Si surface. Two critical parameters, the temperature of thermal dewetting processes and the duration of RIE, have been experimentally studied to achieve very low reflectance from SAS. All the SAS have well-tapered shapes that the refractive index may be changed continuously and monotonously in the direction of incident light. In the wavelength range from 350 to 1800 nm, the measured reflectance of the fabricated SAS averages out to 5%. Especially in the wavelength range from 550 to 650 nm, which falls within visible light, the measured reflectance is under 0.01%.</P>

Comparison of the physicochemical properties of fermented squid sauce supplemented with vitamin C and commercial low-salt soy sauces

Youngjae Cho,Junggyu Lee,Yoon Jung Lee,HeeJeong Choi,SangYoon Lee,Dong Hyeon Park,JingJing Bai,Eunji Kwak,Junhwan Bae,Honggyun Kim,Mi-Jung Choi 한국산업식품공학회 2017 학술대회 및 심포지엄 Vol.2017 No.11

Salt is generally used for food seasonings and preservations as a common ingredient. However, excess salt intake has generated health issues such as high blood pressure, osteoporosis, stroke, and heart diseases. Recently, desires and interests of low-salt cooking have been increased among people who want healthy diets. The aim of study was to compare the physicochemical characteristics of a fermented squid sauce added with vitamin C and commercial low-salt soy sauces. Thawed and crushed squids were fermented until the solid squid became liquid at 25°C with an addition of 5% (g/g) vitamin C. Then, fermented squid sauce was heated at 100°C for 30 min and filtered. All samples were measured in multiple aspects of amino acid nitrogen, salt, sugar and water content, pH, chromaticity and brown color, and sensory test. In the results, color values showed no significantly difference between all the samples (p>0.05). Water content value of the fermented squid sauce was the highest among samples. Brown color, salt contents and sugar contents of the fermented squid sauce were significantly different than other low salt soy sauces with an exception of the sauce made with functional salt. These results showed a similar tendency as those of sensory evaluation. As conclusion, the possibility of fermented squid sauce added with vitamin C showed a possibility as a candidate of low-salt soy sauce.