• Biomolecules & Therapeutics
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• 제31권6호
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• pp.640-647
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• 2023

The skin, the largest organ in the body, undergoes age-related changes influenced by both intrinsic and extrinsic factors. The primary external factor is photoaging which causes hyperpigmentation, uneven skin surface, deep wrinkles, and markedly enlarged capillaries. In the human dermis, it decreases fibroblast function, resulting in a lack of collagen structure and also decreases keratinocyte function, which compromises the strength of the protective barrier. In this study, we found that treatment with γ-aminobutyric acid (GABA) had no toxicity to skin fibroblasts and GABA enhanced their migration ability, which can accelerate skin wound healing. UVB radiation was found to significantly induce the production of matrix metalloproteinase 1 (MMP-1), but treatment with GABA resulted in the inhibition of MMP-1 production. We also investigated the enhancement of filaggrin and aquaporin 3 in keratinocytes after treatment with GABA, showing that GABA can effectively improve skin moisturization. In vivo experiments showed that oral administration of GABA significantly improved skin wrinkles and epidermal thickness. After the intake of GABA, there was a significant decrease observed in the increase of skin thickness measured by calipers and erythema. Additionally, the decrease in skin moisture and elasticity in hairless mice exposed to UVB radiation was also significantly restored. Overall, this study demonstrates the potential of GABA as functional food material for improving skin aging and moisturizing.

• Clinical and Experimental Reproductive Medicine
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• 제44권2호
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• pp.90-95
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• 2017

Objective: We investigated whether the insemination method (in vitro fertilization [IVF] or intracytoplasmic sperm injection [ICSI]) affected morphokinetic events and abnormal cleavage events in embryonic development. Methods: A total of 1,830 normal fertilized embryos were obtained from 272 IVF and ICSI cycles that underwent ovum retrieval culture using a time-lapse system (Embryoscope) from June 2013 to March 2015. All embryos were investigated by a detailed time-lapse analysis that measured the developmental events in the hours after IVF or ICSI insemination. Results: No significant differences were observed between the two groups regarding clinical outcomes (p>0.05). ICSI-derived embryos showed significantly faster morphokinetics than those derived from conventional IVF, from the time to pronuclear fading to the time to 6 cells (p<0.05). However, no significant differences were found from the time to 7 cells to the time to expanded blastocyst (p>0.05). There were no differences in abnormal cleavage events between the two groups (p>0.05); they showed the same rates of direct cleavage from 1 to 3 cells, 2 multinucleated cells, 2 uneven cells, and reverse cleavage. Conclusion: The morphokinetics of embryo development was found to vary between IVF- and ICSI-fertilized oocytes, at least until the 6-cell stage. However, these differences did not affect the clinical outcomes of the embryo. Additionally, no significant differences in abnormal cleavage events were found according to the fertilization method.

• 한국연초학회지
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• 제16권2호
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• pp.181-190
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• 1994

Various active carbons were made from plant sources of coconut shell, pine tree, oak tree and lignite coal. Pore characteristics of these adsorbents were investigated. 1, With increasing activation time, specific surface area and pore volume increased, but the development of micropores was limited at a certain level. The average pore diameter, by BET, of coconut active carbon was 15.5-21.8$\AA$ and that of lignite carbon was 15.6-31.3$\AA$. The pore diameters of silica-gel, sepiolite and zeolite was 30.9$\AA$, 58.6$\AA$ and 55.7$\AA$, respectively. 2. The Horvath - Kawazoe micropore diameter of coconut shell active carbon was under 10.5$\AA$ and that of the other active carbon was under 20.9$\AA$ but silica-gel 33$\AA$, sepiolite 103 $\AA$ and zeolite was unexpectedly large to be 175$\AA$. From the difference between BET micropore diameter and Howath - Kawazoe diameter, it could be said that silica - gel has comparatively uniform pore diameter but sepiolite and zeolite have very uneven diameter. 3. Total pore volume of coconut shell active carbon was 0.27-1.04 cm3/g but that of the other active carbon, 0.23-0.62 cm3/g, was much lower than that of coconut shell active carbon. Hydrophilic adsorbent silica - gel and sepiolite showed big difference in specific surface area, but pore volumes of these were 0.47 and 0.56 cm3/g showing similar value and micropore volumes of these were, respectively, 0.06 cm3/g and 0.04 cm3/g. Total pore volume of zeolite was 0.1 cm3/g and that of micropore was only 0.02 cm3/g.

• 한국지리정보학회지
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• 제6권3호
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• pp.139-150
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• 2003

한국 연근해역의 중규모 해양 환경변동이 Cochlodinium polykrikoides 적조의 시공간 분포 변동과 밀접한 관련성이 있는 것으로 나타났다. 매년 하계 한국 연안역에서 적조가 최초로 발생한 전남 고흥 나로도 연안의 해양환경 상태는 최근 7년(1995~2001) 동안 열염전선대에 위치하였다. 대규모 적조발생은 7년 동안 매 홀수해(1995, 1997, 1999, 2001)에 나타났는데 동중국해 북부해역에서 표면 수온 및 염분의 큰 변동 또한 격년 주기로 나타났다. 저온 고염(홀수해), 고온 저염(짝수해)의 중규모적 해황 변동에 따라 적조의 공간분포 규모가 크게 변동되는 것으로 추정되었다. 한편, 동해연안으로 유입 확산되는 C. polykrikoides 적조의 분포와 이동상황은 동해남부 연안에서 발생하는 냉수대의 시공간 변동 규모에 따라 다르게 나타났다.

• Journal of Animal Science and Technology
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• 제63권1호
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• pp.1-15
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• 2021

As a result of intensive breeding, litter size has considerably increased in pig production over the last three decades. This has resulted in an increase in farrowing complications. Prolonged farrowing will shorten the window for suckling colostrum and reduce the chances for high-quality colostrum intake. Studies also agree that increasing litter sizes concomitantly resulted in decreased piglet birth weight and increased within-litter birth weight variations. Birth weight, however, is one of the critical factors affecting the prognosis of colostrum intake, and piglet growth, welfare, and survival. Litters of uneven birth weight distribution will suffer and lead to increased piglet mortality before weaning. The proper management is key to handle the situation. Feeding strategies before farrowing, management routines during parturition (e.g., drying and moving piglets to the udder and cross-fostering) and feeding an energy source to piglets after birth may be beneficial management tools with large litters. Insulin-like growth factor 1 (IGF-1)-driven recovery from energy losses during lactation appears critical for supporting follicle development, the viability of oocytes and embryos, and, eventually, litter uniformity. This paper explores certain management routines for neonatal piglets that can lead to the optimization of their colostrum intake and thereby their survival in large litters. In addition, this paper reviews the evidence concerning nutritional factors, particularly lactation feeding that may reduce the loss of sow body reserves, affecting the growth of the next oocyte generation. In conclusion, decreasing birth weight and compromised immunity are subjects warranting investigation in the search for novel management tools. Furthermore, to increase litter uniformity, more focus should be placed on nutritional factors that affect IGF-1-driven follicle development before ovulation.

• Plant Breeding and Biotechnology
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• 제6권4호
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• pp.391-403
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• 2018

Genome resequencing by next-generation sequencing technology can reveal numerous single nucleotide polymorphisms (SNPs) within a closely-related cultivar group, which would enable the development of sufficient SNP markers for mapping and the identification of useful genes present in the cultivar group. We analyzed genome sequence data from 13 Korean japonica rice varieties and discovered 740,566 SNPs. The SNPs were distributed at 100-kbp intervals throughout the rice genome, although the SNP density was uneven among the chromosomes. Of the 740,566 SNPs, 1,014 SNP sites were selected on the basis of polymorphism information content (PIC) value higher than 0.4 per 200-kbp interval, and 506 of these SNPs were converted to Kompetitive Allele-Specific PCR (KASP) markers. The 506 KASP markers were tested for genotyping with the 13 sequenced Korean japonica rice varieties, and polymorphisms were detected in 400 KASP markers (79.1%) which would be suitable for genetic analysis and molecular breeding. Additionally, a genetic map comprising 205 KASP markers was successfully constructed with 188 $F_2$ progenies derived from a cross between the varieties, Junam and Nampyeong. In a phylogenetic analysis with 81 KASP markers, 13 Korean japonica varieties showed close genetic relationships and were divided into three groups. More KASP markers are being developed and these markers will be utilized in gene mapping, quantitative trait locus (QTL) analysis, marker-assisted selection and other strategies relevant to crop improvement.

• Journal of Mechanical Science and Technology
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• 제16권8호
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• pp.1089-1094
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• 2002

Mobile communication industry powered by electronics and information technology is building a transforming way for human communication. The latest electronics is so saturated to forget the difficulty in size reduction of electronic parts. However, mechanical parts, such as dynamic speakers and vibration motors, are intrinsically not easy to realize size reduction due to their construction. In this paper, a hexahedral type with simpler configuration is introduced to substitute for the conventional vibration motors. For uneven magnetic field analysis of the hexahedral type, FEM was used to determine magnetic flux density. After an analysis of magnetic and mechanical characteristics, it is shown that the coil configuration is the most important parameter to increase the output torque, and thus vibration. For optimization, genetic algorithm is used to find the optimal configuration of coil to maximize the output torque. Experimental results are also followed to confirm the validity of the proposed design.

• 복합신소재구조학회 논문집
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• 제6권1호
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• pp.51-58
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• 2015

Global buckling is a bending of pipeline and it occurs when the stability of pipeline is distributed by excessive axial force. Subesea pipeline is subjected to axial force induced by temperature and pressure from well and resulting phenomena should be controlled in appropriate manner. Global buckling of subsea pipeline is still ongoing research subject and is studied various organization. In this study, various control methods such as buoyancy module, sleeper, and snake lay for global buckling of subsea pipeline were numerically investigated with various design parameters. From the numerical simulation results, the global buckling control method using sleepers shows better results than buoyancy module and snake lay control methods in the sense of combined stress after buckling. Furthermore, the global buckling of full scale pipeline of 80km with uneven seabed profile were successfully managed when the sleeper was installed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1107-1114
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• 2005

The running condition of multi-system air conditioner is prone to vary largely as it is designed for individual conditioning in each space of middle and small sized buildings. This leads to overcooling in case of partial load run, while the lack of capacity happens in case of full load run. Besides these, there exist such problems as instabilities due to the uneven refrigerant distribution caused by fluctuation of load and the change in piping line. Based upon the basic study on the function characteristics found in parts needed for maximized system working design in order to troubleshoot, the system functioning pattern should be identified through the different tests with various operating circumstances and the analysis models should be developed. With this ground, the control logic has to be made to have a control over capacity and make possible the efficient distribution of refrigerant.

• 펄프종이기술
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• 제38권4호
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• pp.41-46
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• 2006

Printed mottle of coated paper is one of the most common but the most difficult problem in offset printing. Printed mottle is caused by an uneven penetration of Ink into the paper, binder migration, etc. For a high quality printing, development of new paper coating technologies to prevent print mottle is required. So for, the study of solving printed mottle is coated paper absorption controlled by base paper sizing and coating layer binder migration control. As a results, printed mottle has improved in coated paper. But printing is worked by interaction of printing ink, coated paper and printing pressure, then we need to understand of interaction printing work and coated paper. This research focused on a way of improving printed mottle by investigating various printing conditions such as ink dispersion, nip condition and amount of ink transfer using IGT printability tester.