• Journal of Embryo Transfer
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• v.32 no.3
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• pp.165-170
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• 2017

Pigs have been extensively used as mediators of xenotransplantation research. Specifically, the Massachusetts General Hospital (MGH) miniature pig was developed to fix major histocompatibility antigens for use in xenotransplantation studies. We generated transgenic pigs for xenotransplantation using MGH pigs. However, it has not been studied yet whether these pigs show similarity of reproductive physiological characteristics to wild types of MGH miniature pig. In this study we analyzed the estrous cycles and pregnancy characteristics of wild type (WT) and transgenic MGH miniature pigs, which were ${\alpha}1,3$-galactosyltransferase (GalT) heterozygous and homozygous knock-out, and membrane cofactor protein (MCP) inserted in its locus, $GalT^{-MCP/+}$ and $GalT^{-MCP/-MCP}$ pigs. Estrous cycles of WT, $GalT^{-MCP/+}$ and $GalT^{-MCP/-MCP}$ pigs were $20.9{\pm}0.74$, $20.1{\pm}1.26$, and $17.3{\pm}0.87days$, respectively, and periods of estrous were $3.2{\pm}0.10$, $3.1{\pm}0.12$, and $3.1{\pm}0.11days$. The periods of gestation of WT, $GalT^{-MCP/+}$ and $GalT^{-MCP/-MCP}$ pigs were $114.2{\pm}0.37$, $113.3{\pm}0.67$, and $115.4{\pm}0.51days$, respectively. Litter sizes of WT, $GalT^{-MCP/+}$ and $GalT^{-MCP/-MCP}$ pigs were $4.8{\pm}0.35$, $4.8{\pm}1.11$ and $3.0{\pm}0.32$ respectively. There were no significant differences on estrous cycle, periods of estrous and gestation, and litter size among WT, $GalT^{-MCP/+}$ and $GalT^{-MCP/-MCP}$ pigs, meaning that GalT knock-out and additional expression MCP of the MGH miniature pig did not effect on reproduction traits. These results provide relevant information to establish breeding system for MGH transgenic pig, and for propagation of $GalT^{-MCP/-MCP}$ pig to supply for xenotransplantation research.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.645-654
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• 2014

This study was conducted to investigate the effect of 1-methylcyclopropene (1-MCP, $1.0{\mu}L{\cdot}L^{-1}$), a known ethylene action inhibitor, on fruit quality and incidence of physiological disorders during a simulated marketing period at $25^{\circ}C$ for 20 days in early-season Asian pear (Pyrus pyrifolia Nakai) 'Hanareum' that had been treated with 0, 0.5, 1.2 or 2.4% $GA_{4+7}$. Weight loss of stored fruits increased with $GA_{4+7}$ concentration, and the 1-MCP treatment slightly reduced the weight loss rates during the marketing period. Flesh firmness decreased abruptly in all 1-MCP-untreated fruits as the storage period extended to 10 d, whereas the firmness of 1-MCP-treated fruits remained high (> 30 N) during 15 days shelf-life. The effect of 1-MCP was significantly reduced when fruits were subjected to increased GA concentration. Higher soluble solids content and acidity during extended shelf-life were also apparent in 1-MCP-treated 'Hanareum' pears. The L-values (lightness) and hue angles of 1-MCP treated samples were higher than those of controls during 20 days shelf-life, but the a-value (redness) was lower in 1-MCP treated fruits. 1-MCP treatment did not decrease the level of ethylene evolution regardless of $GA_{4+7}$ concentration during shelf-life in early-season Asian pear 'Hanareum'. By contrast, 1-MCP treatment decreased the respiration rate significantly during shelf-life. The efficacy of 1-MCP was greatest in the GA-untreated fruit and was reduced as the $GA_{4+7}$ concentration increased. 1-MCP treatment influenced the severity of physiological disorders including core browning and mealiness: 1-MCP treatment completely blocked the incidence of core browning of during 15 days shelf-life, and reduced the severity of mealiness during 20 days shelf-life regardless of $GA_{4+7}$ concentration. Based on our results, we conclude that the use of $1{\mu}L{\cdot}L^{-1}$ 1-MCP can be of great benefit for maintaining quality and preventing physiological disorders in early-season pear cultivar 'Hanareum' pear, whereas its efficacy decreases with the concentration of $GA_{4+7}$ whereas its efficacy gradually decreases when the concentration of $GA_{4+7}$ paste increased.

• Food Science and Preservation
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• v.16 no.5
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• pp.629-635
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• 2009

We investigated the prolongation of freshness and quality during storage of muskmelons harvested at different times and treated with 1-MCP. The weight loss rate increased in all samples as the storage period was extended, although the weight loss of 1-MCP-treated samples was lower than that of controls, regardless of the degree of maturation. Additionally, the hardness of 1-MCP-treated samples was higher than that of controls, again independent of maturation stage. Specifically, 1-MCP treatment delayed softening of muskmelons, as 1-MCP- treated samples showed a high hardness value after 22 days of storage, whereas hardness of control samples decreased rapidly after 10 days. The soluble solid level in muskmelons harvested 92 days after planting was $14.3^{\circ}$ Brix, whereas that of fruit harvested after 90 days was $12.7^{\circ}$ Brix. There was no significant difference in the acidity of 1-MCP-treated samples and controls after 7 days of storage, although the acidity of 1-MCP-treated fruit was greater than that of controls after 13 days, regardless of the degree of maturation. The L-values (lightness) of 1-MCP treated samples were higher than those of controls for the first 10 days of storage, but the reverse was true after 13 days of storage. The b-values (yellowness) were high in control fruits during the initial period of storage, but greater in 1-MCP treated samples after 19 days of storage. The respiration rate of 1-MCP treated samples was lower than that of controls, regardless of the degree of maturation. Sensory evaluation revealed that the texture of control fruit decreased as storage time rose, whereas that of 1-MCP-treated samples did not fall until 28 or 34 days of storage (p<0.05). Overall acceptability based on a marketable score of 5 points showed that 1-MCP-treated muskmelons scored higher than controls, and remained fresher on storage.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.985-989
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• 2010

This experiment was conducted to clarify the effects of 1-methylcyclopropene (1-MCP) on vase life of cut 'Blue Magic' iris. Pretreatment for 4 h with concentrations of 500 nL and 1000 nL 1-MCP, an inhibitor of ethylene action, inhibited the wilting and inrolling response of cut iris. The vase life of iris flowers of 500 nL or 1000 nL 1-MCP treatment was prolonged to 0.5 day compared to those held in distilled water (control). Vase life of iris showed no significant difference between $3{\mu}L{\cdot}L^{-1}$ ethylene exposure after 1-MCP treatment and control. 1-MCP treatment inhibited inrolling and increased fresh weight, water uptake, and water balance. The increase of fresh weight was high in 500 nL 1-MCP treatment and water uptake was increased by 1000 nL 1-MCP. Especially, iris flower without 1-MCP treatment dramatically decreased the water uptake as compared to the control for four or five days. Water balance of iris flowers held in water was changed to minus value faster than those with pretreatment of 1-MCP.

• Korean Journal of Agricultural Science
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• v.36 no.2
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• pp.147-158
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• 2009

This study was conducted to investigate the effect of 1-MCP, market temperature and combination treatment of freshing agent with 1-MCP on fruit quality of 'Hong Bak' peach (Prunus persica Batsch). The 1-MCP treatment at the rate of 1000ppb showed the best results in delaying the firmness loss and skin color development during shelf life without any detrimental effects on fruit quality. Moreover, positive effects of 1-MCP on fruit quality parameters were more significant in the fruits stored at $30^{\circ}C$ of high temperature shelf life than those of $20^{\circ}C$. The combination treatment of carbon ceramic with 1-MCP showed a beneficial effects including a prevention of firmness loss and maintaining external appearance during the five days of room temperature storage of 'Hong Bak' peach.

• Food Science and Preservation
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• v.17 no.5
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• pp.595-601
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• 2010

We investigated the effects of 1-methylcyclopropene (1-MCP) treatment (0, 0.5, and 1.5 ppm) for 16 hours, followed by storage at ambient temperature, on the qualities of pears (Pyrus pyrifolia c.v. "Hwasan"). Color differences, as measured using the Hunter L, a, and b values, showed the greatest decreases before storage, and 8 weeks after storage, when fruit was exposed to 1.5 ppm 1-MCP. The sensory qualities of c.v. "Hwasan" pears were good until 4 weeks of storage after treatment with 0 ppm 1-MCP, until 6 weeks when 0.5 ppm 1-MCP was employed, and until 7 weeks when 1.5 ppm 1-MCP treatment was performed. Fruit and storage quality in terms of all of hardness, sugar content, PPO activity, respiration amount, and ethylene production increased in the 8 weeks after application of 1.5 ppm 1-MCP. Consequently, it seems that 1-MCP treatment, especially at 1.5 ppm, before storage of pears at ambient temperature, effectively improves the quality of pears of c.v. "Hwasan".

• The Journal of Korean Institute of Information Technology
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• v.16 no.11
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• pp.43-49
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• 2018

Computer simulation was performed using the SIMION program to develop an electron gun for MCP cleaning. The target, MCP, is located 180mm from the source of the electron gun, and the diameter of the MCP is approximately 20mm. Therefore, we tried to find the condition that the beam diameter of electrons reaching the MCP is to be 20mm using four variables such as E, ${\phi}$, d1, d2, where the E is the energy of the electron reaching the MCP, the ${\phi}$ is the diameter of the extractor, and the d1 and the d2 are the distance from the electron source to the end of the extractor tube, and to the wall of chamber, respectively. As a result of simulation, we figuried out that the E and the d2 have little effect on the beam diameter. On the other hand, we also found that the beam diameters were very sensitive to the d1 and varied relatively large with respect to the ${\phi}$, and the d1 was the secondary order function of the ${\phi}$. Therefore we found that this function will allow us to design electron guns that are suitable for the purposes of this study.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.186.2-187
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• 2003

에틸렌 작용억제제인 1-MCP(1-methylcyclopropene) 처리에 따른 토마토의 선도연장효과를 검정하기 위해 본 연구는 수행되었다. 토마토“슈퍼도태랑(Supermomotaro)”품종을 Mature green 단계에서 수화한 다음 1-MCP를 2$0^{\circ}C$에서 250, 500, 및 1000ppb 의 농도로 4시간 동안 처리후 온도 2$0^{\circ}C$, 90% RH 조건에 저장하면서 에틸렌 발생, 호흡량 및 품질특성 변화를 조사하였다. 토마토의 에틸렌 발생은 모든 처리구에서 저장 2일째 급등하는 경향을 보였는데, 1-MCP 처리구는 무처리에 비해 그 급등정도가 낮았으며, 호흡량 또한 1-MCP 처리에 의해 효과적으로 억제되었다. 특히 처리 2일 후부터 무처리에 비해 2배정도 낮은 호흡량을 나타냈다. 과피의 착색진행 정도를 Hunter color의 적색도“a”값으로 비교한 결과, 무처리는 2일부터 6일까지 빠르게 증가하였지만 1-MCP 처리구는 그 증가 속도가 낮았으며, 처리농도가 높을수록“a”값의 변화가 적은 경향을 보였다. 또한 황색도“b”값의 비교에 있어서도 1-MCP 처리구가 무처리에 비해 그 변화가 적었다. 경도는 무처리에서 2일 후에 급격히 감소하는데 비해 1-MCP처리에서는 4일까지 그 감소 폭이 적었으며, 1-MCP처리 농도별 차이는 크지 않았다. 부패과 발생은 무처리와 500ppb 처리에서 비슷한 수준이었으며, 1000ppb 처리에서는 오히려 무처리에 비해 부패율이 높아 고농도 처리에 의한 장해로 판단되었다. 그러나 250ppb 처리는 무처리에 비해 부패율이 적게 나타났다.

• Journal of the Korea Society for Simulation
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• v.26 no.1
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• pp.69-75
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• 2017

An MCP(Multi-chip Package) is a package consisting of several chips. Since several chips are stacked on the same substrate, multiple assembly steps are required to make an MCP. The characteristics of the chips in the MCP are dependent on the layer sequence. In the MCP manufacturing process, it is very essential to carefully consider the layer sequence in scheduling to achieve the intended throughput as well as the WIP balance. In this paper, we propose a scheduling methodology considering the layer sequence constraint.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.118-122
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• 2016

This study was conducted to identify the effects of 1-MCP and the storage methods for maintaining the quality of asparagus spears. Asparagus spears treated 1-MCP stored in MA condition and perforated film (conventional condition) and 1-MCP non-treated used as control. The treated asparagus was stored at $4^{\circ}C$ for 40 days. The fresh weight loss rate was less than 0.2% in all MA (Modified atmosphere) storage treatments, including the 1-MCP treatment, and 1-MCP shown the less fresh weight loss rate in perforated film storage after 20 days storage. The carbon dioxide concentration within a package was 5-12% in MA storage, which is whith the tolerated range of maximum $CO_2$ content of asparagus spears in recommended CA or MA conditions. The oxygen content was maintained between 5 to 15% in MAP treatments. The ethylene content was lowest at the MA storage with 1-MCP treatment. Visual quality, off-flavor, soluble solid contents, and hue angle on the final storage day were higher in MA storage and the 1-MCP treatment and conventional MA storage did not show any significant differences. These results suggest that the 1-MCP treatment did not significantly affected the quality and storability of asparagus spears.