• Journal of Photoscience
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• v.5 no.4
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• pp.169-174
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• 1998

Photosynthetic responses to dehydration were examined by the simulataneous measurement of O2 evolution and chlorophyll (Chl) fluorescence in green pepper leaves. Dehydration was induced by immersing the plant roots directly in the Hoagland solution containing varying concentration (2-30%) of polyethylene glycol(PEG-6000) . Water potential of the leaf was decreased time-and concentation -dependently by PEG-treatment. The decrease in water potential of leaf was correlated with the decrease in both the maximal photosynthesis (Pmax) and quantum yield of O2 evolution, but Pmax dropped more rapidly than quantum yield at all water deficit conditions tested. However, Chl fluorescence parameters were not affected much. Dehydration did not change the initial fluorescence (Fo) and maximum photochemical efficiency(Fv/Fm) of photosystem(PS) II. Both the photochemical quenching (qP) and non-photochemical quenching(NPQ) were not changed by dehydration under low PFR(50 $\mu$mols m-2s-1 ). In contrast, under high PFR(270$\mu$mols m-2s-1)qP was slightly decreased while NPQ was greatly increased. The fast induction kinetics of Chl fluroecence showed no change in Chl fluorescence pattern by dehydration at high PFR (640 $\mu$mols m-2s-1 ), but exhibited a significant drop in peak level(Fp)at low PRFR (70$\mu$mols m-2s-1 ). PS I oxidation and reduction kinetics revealed normal reduction but delayed oxidation to P-700+, suggesting no lesionin electron flow from PSII to PSI , but impaired electron transport to NADP+,These results suggest that water stress caused by PEG-treatment results in the reduction of photosynthesis, promarily due to the reducted electron trasport from PSI to NADP+ or hampered subsequent steps involving Calvin Cycle.

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.161-168
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• 2004

Optimal regeneration conditions of ginseng transformants were studied. It has been known that Ferritin Light Heavy Chain (FLHC) gene remove the several heavy metal by combination, store and transport. To obtain the ginseng tolerant to heavy metal, binary vector was introduced in Agrobacterium by tri-parental mating and then Agrobacterium tumefaciens MP90/FLHC was selected on the AB media and MS media containing kanamycin. Explants were co-cultured with Agrobacterium tumefaciens MP90/FLHC, which contained NPT II as a selectable marker, tadpole ferritin heavy chain (FLHC) gene and human ferritin light chain gene and then a number of embryos were induced. The induced embryo transferred to shooting media consisting of MS medium supplemented with GA 10 mg/L. As a result of examination that induced the normal growth of transfomants, transformants showed the equivalent growth in both root and shoot on the media containing the 1/3 MS.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.107-107
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• 2022

The increase in atmospheric temperature due to climate change prolongs the period of exposure to high-temperature environments during rice cultivation. In particular, high-temperature during early seed development greatly affects on the productivity and quality of rice. The high temperature at this time not only affects the transport and distribution of assimilates from leaves to seeds and the accumulation of starch in the seeds, but also affects the leaves, which are the production organs of assimilates, and increases the consumption of assimilation products due to an increase in respiration. Therefore, in this study, rice was grown in temperature gradient chambers(TGC) to analyze the effects of high temperature on physiological responses, assimilate production, and changes in gene expression in rice leaves. Analysis of chlorophyll and sugar contents and RNA-seq experiments were performed using flag leaves collected under normal and elevated temperature conditions, respectively, during the early seed development stage, and then these results were comprehensively discussed.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.861-867
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• 2023

Lairages serve several functions, such as providing post-mortal inspections and providing a reservoir of animals to ensure the slaughter line runs efficiently. High stress lairage conditions can contribute to the accumulation of transport stress in pigs, causing poor pork quality and still stressed pigs at slaughter. The objective of this study was to investigate meat quality, blood profile and behavior changes according to lairage stocking density in in high temperature. Density treatments were as follows: LD, low density (lower than 0.5 m²/100 kg); ND, normal density (0.5 m²/100 kg to 0.83 m²/100 kg); HD, high density (higher than 0.83 m²/100 kg). Air temperature treatment was as follows: HT, high temperature (higher than 24℃). Pigs stocked with LD showed lower pH, WHC (water holding capacity), and higher DL (drip loss) and CL (cooking loss) than those stocked with HD. Pigs stocked with LD showed lower cortisol level than those stocked with HD. Therefore, Pigs exposed to high stock density (lower than 0.5 m²/100 kg) in high air temperature during pre-slaughter caused acute stress and lead to PSE (pale, soft, exudative) pork incidence. Based on obtained results, stocking of too high (lower than 0.5 m²/100 kg) density is generally not good for meat quality and animal welfare at high temperatures.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.1 no.1
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• pp.22-32
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• 2002

This paper describes about non-burial AVI (Automatic Vehicle Identification) system using general vehicle as probe car for obtaining more accurate traffic information while conserving road pavement surface. Existing spot traffic detectors have their own limits of not obtaining right information owing to its mathematical method. Burial AVI systems have some defects, causing traffic jam, needing much maintenance cost because of frequent cutting of loop and piezo-electric sensors. Especially, they have hard time to make right detection, when it comes to jamming time. Therefore, in this paper, we propose non-burial AVI system with laser trigger unit. Proposed non-burial AVI system is developed to obtain regional traffic information from normal Passing vehicle by automatic license number recognition technology. We have adapted it to national highway section between Suwon city and Pyong$\~$Taek city(9.5km) and get affirmative results. Vehicle detection rate of laser trigger unit is more than 95$\%$, vehicle recognition rate is 87.8$\%$ and vehicle matching rate is about 14.3$\%$. So we regard these as satisfying results to use the system for traffic information service. We evaluate proposed AVI system by regulation of some institutions which are using similar AVI system and the proposed system satisfies all conditions. For future study, we have plan of detailed research about proper lane number from all of the target lanes, optimal section length, information service period, and data fusion method for existing spot detector.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.200-207
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• 2018

At high salt concentration, glycine betaine is transported into Bacillus subtilis and growing rate of the cell is not suppressed. Also according to recent studies, cell growth is maintained normal growth rate at low temperature. Low temperature results in a stress response of Bacillus subtilis that is characterized by strong repression of major metabolic activities such as translation machinery and membrane transport. In this regards, genes showing cold sensitive phenotype are cold-induced DEAD box RNA helicases (ydbR, yqfR) and fatty acid desaturases (bkdR, des). Therefore to understand the effect of glycine betaine on cold growth of Bacillus subtilis, we investigated the effect of glycine betaine on growth rate of these deletion mutants showing cold sensitive phenotype. Glycine betaine strongly stimulated growth of wild type Bacillus subtilis JH642 and deletion mutants of ydbR and yqfR at $20^{\circ}C$ (190~686 min $T_d$ difference). On the other hands, glycine betaine does not show growth promoting effects on deletion mutants of bkdR, and des at cold conditions. Same cold protectant growth results were shown with the precursor choline instead of glycine betaine. We investigated the effects of detergents on the cell membrane in bkdR and des deficient strains associated with cell membrane. It was identified that bkdR deficient strain shows retarded growth with detergent such as Triton X-100 or N-lauryl sarcosine compared with wild type cell. Thus, it is possible that deletion mutation of bkdR modifies membrane structure and effects on transport of glycine betaine.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.6
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• pp.123-132
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• 2012

Gas sensors has been used very differently that depending on following purposes; Automotive (exhaust gas, fuel mixture gas, oxygen, particulates), agriculture / food industry (fresh, stored, CO2, humidity, NH3, nitrogen oxide gas, organic gas, toxic gas emitted from pesticides and insecticides), industrial / medical (chemical gas, hydrogen, oxygen and toxic gases), military (chemical weapon), environmental measurements (CO and other air pollution consisting of sulfur and nitrogen gas), residential (LNG, LPG, butane, indoor air, humidity). The types of industrial toxic substances are known about 700 species and many of these exist in gaseous form under normal conditions. he multi-gas detection sensors will be developed for casualties that detect the most important and find easy three kinds of gases in marine plant; carbon dioxide(CO2), carbon(CO), ammonia(NH3). Package block consists of gas sensing device minor ingredient, rf front end, zigbee chip. Develope interworking technology between the sensor and zigbee chip inside a package. Conduct a performance test through test jig about prototype zigbee sensor module with rf output power and unwanted emission test. This research task available early address when poisonous gas leaked from large industrial site and contribution for workers' safety at the enclosed space.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.4
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• pp.375-387
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• 2019

In this study, the radiation dose rates for the design basis fuel of 360 assemblies CANDU spent nuclear fuel transportation cask were evaluated, by measuring radiation source terms for the design basis fuel of a pressurized heavy water reactor. Additionally, radiological safety evaluation was carried out and the validity of the results was determined by radiological technical standards. To select the design basis fuel, which was the radiation source term for the spent fuel transportation cask, the design basis fuels from two spent fuel storage facilities were stored in a spent fuel transportation cask operating in Wolsung NPP. The design basis fuel for each transportation and storage system was based on the burnup of spent fuel, minimum cooling period, and time of transportation to the intermediate storage facility. A burnup of 7,800 MWD/MTU and a minimum cooling period of 6 years were set as the design basis fuel. The radiation source terms of the design basis fuel were evaluated using the ORIGEN-ARP computer module of SCALE computer code. The radiation shielding of the cask was evaluated using the MCNP6 computer code. In addition, the evaluation of the radiation dose rate outside the transport cask required by the technical standard was classified into normal and accident conditions. Thus, the maximum radiation dose rates calculated at the surface of the cask and at a point 2 m from the surface of the cask under normal transportation conditions were respectively 0.330 mSv·h^-1 and 0.065 mSv·h^-1. The maximum radiation dose rate 1 m from the surface of the cask under accident conditions was calculated as 0.321 mSv·h^-1. Thus, it was confirmed that the spent fuel cask of the large capacity heavy water reactor had secured the radiation safety.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.53-66
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• 1997

Insulin resistance is a prominent feature of diabetic state and has heterogeneous nature. However, the pathogenetic sequence of events leading to the emergence of the defect in insulin action remains controversial. It is well-known that prolonged hyperglycemia and hyperinsulinemia are one of the causes of development of insulin resistance, but both hyperglycemia and hyperinsulinemia stimulate glucose uptake in peripheral tissue. Therefore, it is hypothesized that insulin resistance may be generated by a kind of protective mechanism preventing cellular hypertrophy. In this study, to evaluate whether the acutely increased glucose uptake inhibits further glucose transport stimulated by insulin, insulin sensitivity was measured after preloaded glucose infusion for 2 hours at various conditions in rats. And also, to evaluate the mechanism of decreased insulin sensitivity, insulin receptor binding affinity and glucose transporter 4 (GLUT4) protein of plasma membrane of gastrocnemius muscle were assayed after hyperinsulinemic euglycemic clamp studies. Experimental animals were divided into five groups according to conditions of preloaded glucose infusion: group I, basal insulin ($14{\pm}1.9{\mu}U/ml$) and basal glucose ($75{\pm}0.7mg/dl$), by normal saline infusion; group II, normal insulin ($33{\pm}3.8{\mu}U/ml$) and hyperglycemia ($207{\pm}6.3mg/dl$), by somatostatin and glucose infusion; group III, hyperinsulinemia ($134{\pm}34.8{\mu}U/ml$) and hyperglycemia ($204{\pm}4.6mg/dl$), by glucose infusion; group IV, supramaximal insulin ($5006{\pm}396.1{\mu}U/ml$) and euglycemia ($l00{\pm}2.2mg/dl$), by insulin and glucose infusion; group V, supramaximal insulin ($4813{\pm}687.9{\mu}U/ml$) and hyperglycemia ($233{\pm}3.1mg/dl$), by insulin and glucose infusion. Insulin sensitivity was assessed with hyperinsulinemic euglycemic clamp technique. The amounts of preloaded glucose infusion(gm/kg) were $1.88{\pm}0.151$ in group II, $2.69{\pm}0.239$ in group III, $3.54{\pm}0.198$ in group IV, and $4.32{\pm}0.621$ in group V. Disappearance rates of glucose (Rd, mg/kg/min) at steady state of hyperinsulinemic euglycemic clamp studies were $16.9{\pm}3.88$ in group I, $13.5{\pm}1.05$ in group II, $11.2{\pm}1.17$ in group III, $13.2{\pm}2.05$ in group IV, and $10.4{\pm}1.01$ in group V. A negative correlation was observed between amount of preloaded glucose and Rd (r=-0.701, p<0.001) when all studies were combined. Insulin receptor binding affinity and content of GLUT4 were not significantly different in all experimental groups. These results suggest that increased glucose uptake may inhibit further glucose transport and lead to decreased insulin sensitivity.

• Journal of Korea Water Resources Association
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• v.43 no.10
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• pp.883-891
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• 2010

More recently, there have been significant changes in the forms of channels due to runoff characteristics driven by climate changes and other alterations in basin/channel environments. Particularly, increasing local deposition in major channels is being observed nationwide. Of such phenomena, it is noteworthy that flood-plains show unidirectional growth and lowering of channels within compound channels in the form of a high-flow plain. These changes are supposed to affect management of the river ecology as well as flood control. In this study, the research on channels in Korea confirmed that the phenomenon of local deposition in those channels is actually taking place, rendering a problem to be urgently addressed. Previous studies on bed changes have been focused on low channels based on bed materials distributed over the channels. However, this research has proved that surface-layer deposition of a high-flow plain is closely related with changes in the conditions of ground surfaces and, ultimately, affects the bed of the entire channel as well. According to the intensive research on the condition of the high-flow plain of the mouth of the Han River, the silt deposited in the high-flow plain was the main cause of settlement/growth of vegetation. And this leads to landforming along with woods-forming, disturbing flood control as well as the normal river ecology.