• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.3
• /
• pp.317-322
• /
• 1993

The diffusion phenomena of water, solid and reducing sugar in Chinese cabbage during salting (5$0^{\circ}C$, 25% salt solution) and desalting (5$0^{\circ}C$, distilled water) were investigated. Water loss and solid gain during salting were rapid in the first 6hrs and then almost leveled off. After 24hrs of salting, water loss and solid gain in 100g of initial wet Chinese cabbage were 33.35g and 6.26g respectively. Moisture content was changed from 94.29% to 83.11% during 24hrs of salting. The reducing sugar concentration was also changed from 29.2 mg/$m\ell$ to 6.5mg/$m\ell$, which was linearized as a function of the square root of salting time and showing that Y=30.1841-5.0269√t. After 24hrs salting, water gain and solid loss during desalting were rapid in the first 4hrs and then increased linearly. After 12hrs of desalting, the water gain and solid loss in 100g of initial wet Chinese cabbage were 20.82g and 9.14g respectively. The amount of solid loss after 12hrs desalting was higher than that of solid gain after 24hrs salting due to the diffusion of solute presented initially in the Chinese cabbage during salting and desalting. The concentration of salt in Chinese cabbage after 12hrs desalting was 2.98% which was a suitable salt concentration for the preparation of Kimchi. At this time, the concentration of reducing sugar was only 1.6mg/$m\ell$. The linear regression equation of reducing sugar concentration during desalting was Y=6.7854-1.5992√t.

• Microbiology and Biotechnology Letters
• /
• v.26 no.6
• /
• pp.537-544
• /
• 1998

The cultivation conditions of transformant Alcaligenes eutrophus AER5 harboring cloned phbC gene for mass production of poly (3-hydroxybutyrate-3-hydroxyvalerate)[P(3HB-3HV)] containing high molar fraction of 3-hydroxyvalerate (3-HV) were investigated. In two-stage batch cultivation, transformant accumulated P(3HB-3HV) containing 52.2 mol% of 3HV compared to 30 mol% of parent strain A. eutrophus H16. The increased 3-HV molar fraction was due to the amplified activity of PHB synthase participating in condensation of 3-HB and 3-HV. To increase efficiency of P(3HB-3HV) accumulation, fructose was added along with precursor compound valerate, and total cell mass and P(3HB-3HV) concentrations remarkably increased, but not 3-HV molar fraction. The effect of magnesium ion showed that P(3HB-3HV) concentration and 3-HV molar fraction were significantly increased upto 6.1 g/L and 71.3 mol% at 0.01 g/L of MgSO$_4$, respectively. The efficiency of several pH adjuster, NaOH, NaOH and (NH$_4$)$_2$SO$_4$, and NH$_4$OH, on total cell mass, p(3HB-3HV) concentration, and 3-HV molar fraction was also compared. To overcome the disadvantage of two-stage cultivation, one-stage intermittent fed-batch cultivation was attempted, such a way 10.0 g/L of fructose was supplied for cell growth at initial 36 hr and then 10.0 g/L of valerate and 5.0 g/L of fructose were applied to induce the accumulation of P(3HB-3HV), consequently, 10.4 g/L of P(3HB-3HV) with 38 mol% of 3-HV fraction could be obtained after 72 hr. These results can be used for elucidating cultivation strategy for mass production of P(3HB-3HV) containing high 3-HV molar fraction using transformant A. eutrophus AER5 harboring cloned phbC gene.

• The Bulletin of The Korean Astronomical Society
• /
• v.41 no.2
• /
• pp.44.1-44.1
• /
• 2016

The Sagittarius-Carina spiral arm in the Galaxy contains several massive young open clusters. We present a deep optical photometric study on the massive young open clusters in the Sagittarius-Carina arm, Westerlund 2 and the young open clusters in the ${\eta}$ Carina nebula. Westerlund 2 is a less studied starburst-type cluster in the Galaxy. An abnormal reddening law for the intracluster medium of the young starburst-type cluster Westerlund 2 is determined to be $R_{V,cl}=4.14{\pm}0.08$. The distance modulus is determined from zero-age main-sequence fitting to the reddening-corrected color-magnitude diagrams of the early-type members to be $V_0-M_V=13.9{\pm}0.14mag$. The pre-main sequence (PMS) members of Westerlund 2 are selected by identifying the optical counterparts of X-ray emission sources from the Chandra X-ray observation and mid-infrared emission sources from the Spitzer/IRAC (the Infrared Array Camera) observation. The initial mass function (IMF) shows a slightly flat slope of ${\Gamma}=-1.1{\pm}0.1$ down to $5M_{\odot}$. The age of Westerlund 2 is estimated to be. 1.5 Myr from the main-sequence turn-on luminosity and the age distribution of PMS stars. The ${\eta}$ Carina nebula is the best laboratory for the investigation of the Galactic massive stars and low-mass star formation under the influence of numerous massive stars. We have performed deep wide-field CCD photometry of stars in the ${\eta}$ Carina nebula to determine the reddening law, distance, and the IMF of the clusters in the nebula. We present VRI and $H{\alpha}$ photometry of 130,571 stars from the images obtained with the 4m telescope at Cerro Tololo Inter-American Observatory (CTIO). RV,cl in the η Carina nebula gradually decreases from the southern part (~4.5, around Trumpler 14 and Trumpler 16) to the northern part around Trumpler 15 (~3.5). Distance to the young open clusters in the ${\eta}$ Carina nebula is partly revised based on the zero-age main-sequence fitting to the reddening-corrected color-magnitude diagrams (CMDs) and the (semi-) reddening-independent CMDs. We select the PMS members and candidates by identifying the optical counterparts of X-ray sources from the Chandra Carina Complex Survey and mid-infrared excess emission stars from the Spitzer Vela-Carina survey. From the evolutionary stage of massive stars and PMS stars, we obtain that the northern young open cluster Trumpler 15 is distinctively older than the southern young open clusters, Trumpler 14 (${\leq}2.5 Myr$) and Trumpler 16 (2.5-3.5 Myr). The slopes of the IMF of Trumpler 14, Trumpler 15, and Trumpler 16 are determined to be $-1.2{\pm}0.1$, $-1.5{\pm}0.3$, and $-1.1{\pm}0.1$, respectively. Based on the RV,cl of several young open clusters determined in this work and the previous studies of our group, We suggest that higher RV,cl values are commonly found for very young open clusters with the age of < 4 Myr. We also confirm the correlation between the slope of the IMF and the surface mass density of massive stars.

• Applied Biological Chemistry
• /
• v.41 no.5
• /
• pp.372-376
• /
• 1998

Internal mass transfer during osmotic dehydration of gingers in sugar solution was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration on browning reaction and texture properties of air dried rehydrated was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in the first 3 min and then changed gentle slope. Moisture loss during osmotic dehydration using a sugar solution $(60\;Brix,\;80^{\circ}C)$ with 18 min immersion time was 40.05 g moisture/100 g wet ginger which was 52% reduction of initial moisture content in ginger (83.02%, wet basis). The changes of rate parameter were more affected by temperature than by concentration of sugar solution. Minimum browning degree (O.D.=0.027) was carried out by osmotic dehydration in sugar solution $(40\;or\;50\;Brix,\;80^{\circ}C)$ with 15 min immersion time compared to control (O.D.=0.132). Influence of osmotic dehydration on puncture forces of 3 min rehydrated ginger in boiling water were $22{\sim}34%$ of reduction, while blanching treatment had not affected compared to those of control.

• Annals of Geriatric Medicine and Research
• /
• v.22 no.4
• /
• pp.167-175
• /
• 2018

Sarcopenia, a common clinical syndrome in older adults, is defined as decreased muscle mass, strength, and physical performance. Since sarcopenia is associated with the incidence of functional decline, falls, and even mortality in older adults, researchers and health care providers have been keen to accumulate clinical evidence to advocate the screening and prevention of sarcopenia progression in older adults. The factors that may accelerate the loss of muscle mass and function include chronic diseases, inactivity, and deficiency in appropriate nutritional support. Among these, nutritional support is considered an initial step to delay the progression of muscle wasting and improve physical performance in community-dwelling older adults. However, a nationwide study suggested that most Korean older adults do not consume sufficient dietary protein to maintain their muscle mass. Furthermore, considering age-associated anabolic resistance to dietary protein, higher protein intake should be emphasized in older adults than in younger people. To develop a dietary protein recommendation for older adults in Korea, we reviewed the relevant literature, including interventional studies from Korea. From these, we recommend that older adults consume at least 1.2 g of protein per kg of body weight per day (g/kg/day) to delay the progression of muscle wasting. The amount we recommend (1.2 g/kg/day) is 31.4% higher than the previously suggested recommended daily allowance (i.e., 0.91 g/kg/day) for the general population of Korea. Also, evidence to date suggests that the combination of exercise and nutritional support may enhance the beneficial effects of protein intake in older adults in Korea. We found that the current studies are insufficient to build population-based guidelines for older adults, and we call for further researches in Korea.

• Journal of The Korean Astronomical Society
• /
• v.29 no.1
• /
• pp.63-73
• /
• 1996

The previous study of chemical evolution of the Galaxy is extended to the radial properties of the Galactic disk. The present model includes radial dependency of the time-dependent bimodal IMF, radial flow of material in the disk, and the change of type I supernova explosion rate with radial distance from the disk center as model parameters and observed gas and stellar density distributions and metallicity abundance gradient as observational constraints. The results of two models in this study explain the observed gas and stellar density distributions well, with the slope of the gas density gradient in the region of 4.5 kpc$Y_1$ and -0.123dex/kpc in model $Y_2$, respectively, which fit well the observed gradient of -0.l1dex/kpc. The abundance gradient reproduced in model $Y_1$ is getting flatter with decreasing radius, while that in model $Y_2$ is getting steeper, which fits better the observed abundance gradient. This result shows the necessity of exponentially increasing type I supernova explosion rate with decreasing radius in order to explain the observed abundance gradient in the disk. The fitness of observed density distribution and star formation rate distribution justifies the reliability of time-dependent bimodal IMF as a compound quantitative chemical evolution model of the Galaxy. The temporal variations of metallicity gradients for carbon, nitrogen and oxygen are also shown.

• Korean Journal of Poultry Science
• /
• v.28 no.2
• /
• pp.143-153
• /
• 2001

Using bioinformatic tools for searching the massive genome databases, it is possible to Identify new genes in few minutes for initial discoveries based on evolutionary conservation, domain homology, and tissue expression patterns, followed by further verification and characterization using the bench-top works. The development of high-density two-dimensional arrays has allowed the analysis of the expression of thousands of genes simultaneously in the humans, mice, rats, yeast, and bacteria to elucidate the genes and pathways involved in physiological processes. In addition, rapid and automated protein identification is being achieved by searching protein and nucleotide sequence databases directly with data generated from mass spectrometry. Recently, analysis at the bio-chemical level such as biochemical screening and metabolic profiling (Biochemical genomics) has been introduced as an additional approach for categorical assignment of gene function. To make advantage of recent achievements in computational approaches for facilitated gene discoveries in the avian model, chicken expression sequence tags (ESTs) have been reported and deposited in the international databases. By searching EST databases, a chicken heparanase gene was identified and functionally confirmed by subsequent experiments. Using combination of sub-tractive hybridization assay and Genbank database searches, a chicken heme -binding protein family (cSOUL/HBP) was isolated in the retina and pineal gland of domestic chicken and verified by Northern blot analysis. Microarrays have identified several host genes whose expression levels are elevated following infection of chicken embryo fibroblasts (CEF) with Marek's disease virus (MDV). The ongoing process of chicken genome projects and new discoveries and breakthroughs in genomics and proteomics will no doubt reveal new and exciting information and advances in the avian research.

• Korean Journal of Computational Design and Engineering
• /
• v.15 no.5
• /
• pp.362-374
• /
• 2010

Product Lifecycle Management (PLM) is an integrated business approach to manage the creation and distribution of product information throughout the product development process. From the product perspective, PLM encompasses a holistic approach to product development and product information management. It supports the integrated product information in conjunction with the efficient product structures and BOM (Bill Of Material), user interfaces, proper functions, design processes and enterprise integration. Therefore, PLM should not only satisfy required functions as an enterprise software but also offer a systematic method for the efficient application from the initial stage of its development. Recently, many shipyards have been considering the PLM as a strategic solution to get the efficient management of product information such as 3-D models, BOM, drawings, documents, and the other product data. Though many studies on PLM are performed, most of them are performed in a function-based approach adequate for mass productive assembly industries. It could not help having limitations on applying the proper PLM system to the shipbuilding business since the requirements of shipbuilding PLM are too diverse and huge to design the architecture. This study presents the PLM framework which effectively reflects the diverse requirements of shipbuilding PLM. In order to get the macroscopic architecture of shipbuilding PLM, authors suggest the four-tier architecture model which considers the various requirements collected from shipyards. Entities of ship design data are modeled BOM in terms of product structure and hierarchical class diagram. Applicable functions of shipbuilding PLM are also investigated by analysis of issues of ship design. Finally, by reflecting the design process of shipbuilding, To-Be ship design procedure cooperated with the suggested PLM framework has been summarized.

• Structural Engineering and Mechanics
• /
• v.37 no.6
• /
• pp.671-684
• /
• 2011

Deciding on an optimal sensor placement (OSP) is a common problem encountered in many engineering applications and is also a critical issue in the construction and implementation of an effective structural health monitoring (SHM) system. The present study focuses with techniques for selecting optimal sensor locations in a sensor network designed to monitor the health condition of Dalian World Trade Building which is the tallest in the northeast of China. Since the number of degree-of-freedom (DOF) of the building structure is too large, multi-modes should be selected to describe the dynamic behavior of a structural system with sufficient accuracy to allow its health state to be determined effectively. However, it's difficult to accurately distinguish the translational and rotational modes for the flexible structures with closely spaced modes by the modal participation mass ratios. In this paper, a new method of the OSP that computing the mode shape matrix in the weak axis of structure by the simplified multi-DOF system was presented based on the equivalent rigidity parameter identification method. The initial sensor assignment was obtained by the QR-factorization of the structural mode shape matrix. Taking the maximum off-diagonal element of the modal assurance criterion (MAC) matrix as a target function, one more sensor was added each time until the maximum off-diagonal element of the MAC reaches the threshold. Considering the economic factors, the final plan of sensor placement was determined. The numerical example demonstrated the feasibility and effectiveness of the proposed scheme.

• Bulletin of the Korean Chemical Society
• /
• v.25 no.8
• /
• pp.1195-1201
• /
• 2004

Tyrosinase was covalently immobilized on platinum electrode according to the method we developed for laccase (Bull. Korean Chem. Soc. 2002, 23(7), 385) and p-chlorophenol, p-cresol, and phenol could be detected with sensitivities of 334, 139 and 122 nA/ ${\mu}M$ and the detection limits of 1.0, 2.0, and 2.5 ${\mu}M$, respectively. The response time ($t_{90\%}$) is 3 seconds for p-chlorophenol, and 5 seconds for p-cresol and phenol. The optimal pHs of the sensor are in the range of 5.0- 6.0. This sensor can tolerate at least 500 times repeated injections of p-chlorophenol with retaining 80% of initial activity. In case of tyrosinase and laccase co immobilized platinum electrode, the sensitivities are 560 nA/ ${\mu}M$ for p-phenylenediamine (PPD) and 195 nA/ ${\mu}M$ for p-chlorophenol, respectively. The sensitivity of the bi-enzyme sensor for PPD increases 70% compared to that of only laccase immobilized one, but the sensitivity for p-chlorophenol decreases 40% compared to that of only tyrosinase immobilized one. The sensitivity increase for the bi-enzyme sensor for PPD can be ascribed to the additional catalytic function of the co-immobilized tyrosinase. The sensitivity decrease for p-chlorophenol can be explained by the “blocking effect” of the co-immobilized laccase, which hinders the mass transport through the immobilized layer. If PPD was detected with the electrode that had been used for p-chlorophenol, the sensitivity decreased 20% compared to that of the electrode that had been used only for PPD. Similarly, if p-chlorophenol was detected with PPD detected electrode, the sensitivity also decreased 20%. The substrate-induced conformation changes of the enzymes in a confined layer may be responsible for the phenomena.