• Microbiology and Biotechnology Letters
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• v.51 no.4
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• pp.403-415
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• 2023

This study aimed to isolate and identify L-(+)-lactic acid-producing bacteria from tree barks collected in Thailand and evaluate the potential strain as probiotics. Twelve strains were isolated and characterized phenotypically and genotypically. The strains exhibited a rod-shaped morphology, high-temperature tolerance, and the ability to ferment different sugars into lactic acid. Based on 16S rRNA gene analysis, all strains were identified as belonging to Weizmannia coagulans. Among the isolated strains, BKMTCR2-2 demonstrated exceptional lactic acid production, with 96.41% optical purity, 2.33 g/l of lactic acid production, 1.44 g/g of lactic acid yield (per gram of glucose consumption), and 0.0049 g/l/h of lactic acid productivity. This strain also displayed a wide range of pH tolerance, suggesting suitability for the human gastrointestinal tract and potential probiotic applications. The whole-genome sequence of BKMTCR2-2 was assembled using a hybridization approach that combined long and short reads. The genomic analysis confirmed its identification as W. coagulans and safety assessments revealed its non-pathogenic attribute compared to type strains and commercial probiotic strains. Furthermore, this strain exhibited resilience to acidic and bile conditions, along with the presence of potential probiotic-related genes and metabolic capabilities. These findings suggest that BKMTCR2-2 holds promise as a safe and effective probiotic strain with significant lactic acid production capabilities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.269-277
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• 1995

This experiment was conducted to study on forage utility of native grasses in polderland for salt tolerance plant selection and good feed with collection and evaluation. As the result of investgate, it was carried out feed evaluation, germination physiology and early growth at the different salt content of Puccinellia coreesis Honda and P. nipponica Ohwi from May 1993 to June 1994. Germination physiology of the grasses was light and low temperature favored optimum germination temperature was 1$0^{\circ}C$, germination period was 30 days. Dormancy awakening was needed wet and high temperature condition with 1~3 days storage. Germination rate increased 18.0% of P. coreensis and 39.0% of P. nipponica than those of non treatments. Early growth condition of different salt content was good also at in 1.00% and 0.50% levels of P. coreensis and P. nipponica. Crude protein content was 8.4% at P. coreensis, 7.1% at P. nipponica and 10.3% of Italian ryegrass, and NFE content was arrangement in order of P. coreensis, Italian ryegrass and P. nipponica. TDN content was not different between P. coreensis, P. nipponica and Italian ryegrass. Also P. coreensis and P. nipponica have a good taste for cattle as same as other crops.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.47-58
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• 2023

The quality and yield of crops produced using field cultivation are expected to decrease due to the recent global climate change caused by extreme weather. The plant reproductive stage associated with crop yields is a highly vulnerable period to global warming caused by high temperatures. This study analyzed the adzuki bean's yield properties, antioxidant contents, and pollen viability of adzuki bean (Vigna angularis L.) under high-temperature stress and growth periods in a temperature gradient greenhouse that forms 0 to 4℃ above the outside temperatures. As the main variety of red beans cultivated in Korean farms, the "Arari" red bean was grown in the rain shield greenhouse and the temperature gradient greenhouse from 2021 to 2022 in Milyang, Korea. Compared to 2022, it showed a 0 - 1.0℃ lower temperature during the whole growth period in 2021. However, its average temperatures were 0 - 3.7℃ higher in the vegetative stage and 0.4 - 2.4℃ higher in the anthesis stage in 2021. The lowest yield (6.8 ± 0.7 g) was at the highest temperature (T4: low, 23.6℃; average, 28.5℃; high, 35.8℃) during the anthesis stage in 2021. The temperatures of the mature stage were 1.7 - 3.9℃, which were higher in 2022 than in 2021, although the low temperatures of 2022 were lower than in 2021. The yields of the mature stage in 2022 increased more than in 2021 because of the high temperature of the mature stage. The growth and yield were good at 40.5℃ in the vegetative stage. However, growth was poor when the average temperature was 27.0℃ or higher, and yields decreased during the flowering period. Total polyphenol and flavonoid contents were increased, and the pollen viability was 40.75% in the whole growth period at high temperature (T4: low, 22.9℃; average, 28.8℃; high, 36.9℃). These results showed that the antioxidant levels increased when the antioxidant component was affected at higher temperatures than at normal. In contrast, the pollen viability-related yield decreased as the temperature increased. Our results are the basic data for field growers and the breeding of thermos-tolerance in adzuki beans to prepare for the changeable future climate.

• Journal of Biosystems Engineering
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• v.25 no.3
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• pp.213-220
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• 2000

Grafting of fruit-bearing vegetables has been widely used to increase the resistance to soil-borne diseases, to increase the tolerance to low temperature or to soil salinity, to increase the plant vigor, and to extend the duration of economic harvest time. After grafting, it is important to control the environment around grafted seedlings for the robust joining of a scion and rootstock. Usually the shading materials and plastic films are used to keep the high relative humidity and low light intensity in greenhouse or tunnel. It is quite difficult to optimally control the environment for healing and acclimation of grafted seedlings under natural light. So the farmers or growers rely on their experience for the production of grafted seedling with high quality. If artificial light is used as a lighting source for graft-taking of grafted seedlings, the light intensity and photoperiod can be easily controlled. The purpose of this study was to develop a prototype system for the graft-taking enhancement of grafted seedlings using artificial lighting and to investigate the effect of air current speed on the distribution of air temperature and relative humidity in a graft-taking enhancement system. A prototype graft-taking system was consisted by polyurethane panels, air-conditioning unit, system controller and lighting unit. Three band fluorescent lamps (FL20SEX-D/18, Kumho Electric, Inc.) were used as a lighting source. Anemometer (Climomaster 6521, KANOMAX), T-type thermocouples and humidity sensors (CHS-UPS, TDK) were used to measure the air current speed, air temperature and relative humidity in a graft-taking system. In this system, air flow acted as a driving force for the diffusion of heat and water vapor. Air current speed, air temperature and relative humidity controlled by a programmable logic controller (UP750, Yokogawa Electric Co) and an inverter (MOSCON-G3, SAMSUNG) had an even distribution. Distribution of air temperature and relative humidity in a graft-taking enhancement system was fairly affected by air current speed. Air current speed higher than 0.1m/s was required to obtain the even distribution of environmental factors in this system. At low air current speed of 0.1m/s, the evapotranspiration rate of grafted seedlings would be suppressed and thus graft-taking would be enhanced. This system could be used to investigate the effects of air temperature, relative humidity, air current speed and light intensity on the evaportranspiration rate of grafted seedlings.

• Transactions of Materials Processing
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• v.32 no.6
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• pp.311-320
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• 2023

Recently, lightweight of automotive parts has been required to solve environmental problems caused by global warming. Accordingly, research and development are proceeded on manufacturing of parts using aluminum that can replace steel for lightweight of the automotive parts. In addition, high strength aluminum can be applied to body parts in order to meet both requirements of lightening and improving crash safety of vehicle. In this study, hot blow forming of roof side rail is employed to manufacturing of the automotive parts with high strength aluminum tube. In hot blow forming, longer forming times and excessive thinning can be occurred as compared with conventional manufacturing processes. So optimization of process conditions is required to prevent excessive thinning and to uniformize thickness distribution with fast forming time. Mechanical properties of high strength aluminum are obtained from tensile test at high temperature. These properties are used for finite element(FE) analysis to investigate the effect of strain rate on thinning and thickness distribution. Variation of thickness was firstly investigated from the result of FE analysis according to tube diameter, where the shapes at cross section of roof side rail are compared with allowable dimensional tolerance. Effective tube diameter is determined when fracture and wrinkle are not occurred during hot blow forming. Also FE analysis with various pressure-time profiles is performed to investigate the their effects on thinning and thickness distribution which is quantitatively verified with thinning factor. As a results, optimal process conditions can be determined for the manufacturing of roof side rail using high strength aluminum.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.405-410
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• 2003

Environmental stress is the major limiting factor in plant productivity. In order to evaluate the stress tolerance of potato plants, leaf discs of two potato cultivars, Atlantic and Superior, were subjected to various stress conditions of high temperature, methyl viologen, H2O2, or $H_2O$$_2$. When potato leaf discs were exposed to high temperature at 37$^{\circ}C$ for 84 hr, Atlantic plants, a cultivar with high sensitivity to heat stress, showed about 20％ higher membrane damage than Superior plants. When exposed to 2$\mu$M methyl violgen (MV), a superoxide generating non-selective herbicide, for 36 hr, Atlantic plants also showed about 38％ higher membrane damage than Superior plants, and were more susceptible up to 10$\mu$M MV concentration tested. On treatment with 0.75M NaCl, Atlantic plants also had about 45％ less chlorophyll contents in leaf discs than Superior plants. There was, however, no difference in chlorophyll content of two cultivars at higher NaCl concentrations. The effect of $H_2O$$_2$ on the two cultivars was mixed. At low $H_2O$$_2$ concentration (25 mM) , Superior plants were more susceptible to $H_2O$$_2$stress after 36 hr. However, at high $H_2O$$_2$ concentration (100 mM), Atlantic plants exhibited higher susceptibility after 36 hr. The results indicate that in vitro leaf discs reflecting the whole plants in this study will be useful for selection and characterization of elite transgenic potato plants with enhanced tolerance to environmental stress.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.769-779
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• 2019

Chilli peppers are predominantly cultivated in open field systems under abiotic and biotic stress conditions. Abiotic and biotic factors have a considerable effect on plant performance, fruit quantity, and quality. Chilli peppers grow well in a tropical climate due to their adaptation to warm and humid regions with temperatures ranging from 18 to 30℃. Nowadays, chilli peppers are cultivated all around the world under different climatic conditions, and their production is gradually expanding. Expected climate changes will likely cause huge and complex ecological consequences; high temperature, heavy rainfall, and drought have adverse effects on the vegetative and generative development of all agricultural crops including chilli peppers. To gain better insight into the effect of climate change, the growth, photosynthetic traits, morphological and physiological characteristics, yield, and fruit parameters of chilli peppers need to be studied under simulated climate change conditions. Moreover, it is important to develop alternative agrotechnologies to maintain the sustainability of pepper production. There are many conceivable ideas and concepts to sustain crop production under the extreme conditions of future climate change scenarios. Therefore, this review provides an overview of the adverse impacts of climate change and discusses how to find the best solutions to obtain a stable chilli pepper yield.

• Nuclear Engineering and Technology
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• v.52 no.3
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• pp.597-609
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• 2020

Accident Tolerant Fuels have been widely studied since the Fukushima-Daiichi accident in 2011 as one of the options on how to further enhance the safety of nuclear power plants. Deposition of protective coatings on nuclear fuel claddings has been considered as a near-term concept that will reduce the high-temperature oxidation rate and enhance accidental tolerance of the cladding while providing additional benefits during normal operation and transients. This study focuses on experimental testing of Zr-based alloys coated with Cr-based coatings using Physical Vapour Deposition. The results of long-term corrosion tests, as well as tests simulating postulated accidents, are presented. Zr-1%Nb alloy used as nuclear fuel cladding serves as a substrate and Cr, CrN, Cr_xN_y layers are deposited by unbalanced magnetron sputtering and reactive magnetron sputtering. The deposition procedures are optimized in order to improve coating properties. Coated as well as reference uncoated samples were experimentally tested. The presented results include standard long-term corrosion tests at 360℃ in WWER water chemistry, burst (creep) tests and mainly single and double-sided high-temperature steam oxidation tests between 1000 and 1400℃ related to postulated Loss-of-coolant accident and Design extension conditions. Coated and reference samples were characterized pre- and post-testing using mechanical testing (microhardness, ring compression test), Thermal Evolved Gas Analysis analysis (hydrogen, oxygen concentration), optical microscopy, scanning electron microscopy (EDS, WDS, EBSD) and X-ray diffraction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.13
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• pp.93-105
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• 1973

Differential tolerance of rice varieties, Tongil and Mangyung(or Milsung) varieties, against herbicides combined with Simetryne was investigated by the rate of application in 4 places; Jeonju, Gwangju, Iri and Milyang, whose soil textures were Lic, Sic, CL and Lic respectively. The results are summarized as follows: 1) Jeonju a. Initial crop injury At the rate of 2kg/10a prod. no initial crop injury was caused(both to Mangyung and Tongil varieties) on light clay soil, even when treated at high temperature of $30^{\circ}C$ and above. Crop injury was first caused at 3kg/l0a prod. to Tongil variety and the damage increased in proportion to the increase of application rate, while no crop injury was caused to Mangyung variety even at high rate of 5kg/l0a prod. b. Yield Tongil variety: Under high temperature condition in a vinyl house no statistical difference was observed between treated and hand weeding plot at the rates of 3kg/l0a prod. and below. Under air temperature conditions no statistical difference was observed between treated and hand weeding plot at the rates of 4kg/l0a prod. and below. Mangyung variety: No statistical difference was observed between treated and hand weeding plot at the rates of 5kg/l0a prod. and below both under air and high temperature conditions. 2) Gwangju a. Initial crop injury Although almost the same tendency as in Jeonju was observed, a little lighter crop injury was observed in general in Gwangju than in Jeonju at the time of application. And so, no crop injury was caused to Tongil variety until 4kg/l0a prod. and above. b. Yield Tongil variety: No statistical difference was observed between treated and hand weeding plot at 4kg/l0a prod. and below. Mangyung variety: No statistical difference was observed between treated and hand weeding plot at 4kg/l0a prod. and below. 3) Iri No crop injury was caused both to Tongil and Mangyung varieties at 4kg/l0a prod. and below. Also, no reduction of grain yield was observed. 4) Milyang A little lighter crop injury was observed in general. No crop injury was caused to Milsung variety at 5kg/l0a prod. ; Only a slight crop injury was caused to Tongil variety. Yield: No statistical difference was observed between treated and hand weeding plot both of Tongil and Milsung varieties even at 5kg/l0a prod. and below.

• Nano
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• v.13 no.12
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• pp.1850147.1-1850147.14
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• 2018

In this work, water-soluble and blue-emitting carbon nanodots (CDs) were synthesized from apple peels for the first time via one-step hydrothermal method. The synthetic route is facile, green, economical and viable. The as-prepared CDs were characterized thoroughly by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman, Fourier transform infrared (FT-IR), X-ray photoelectron (XPS), fluorescence and UV-Vis absorption spectroscopy in terms of their morphology, surface functional groups and optical properties. The results show that these CDs possessed ultrasmall size, good dispersivity, and high tolerance to pH, ionic strength and continuous UV irradiation. Significantly, the CDs had fast and reversible response towards temperature, and the accurate linear relationship between fluorescence intensity and temperature was used to design a novel nanothermometer in a broad temperature range from 5 to $65^{\circ}C$ facilely. In addition, the fluorescence intensity of CDs was observed to be quenched immediately by Cr(VI) ions based on the inner filter effect. A low-cost Cr(VI) ions sensor was proposed employing CDs as fluorescent probe, and it displayed a wide linear range from 0.5 to $200{\mu}M$ with a detection limit of $0.73{\mu}M$. The practicability of the developed Cr(VI) sensor for real water sample assay was also validated with satisfactory recoveries.