• The Plant Pathology Journal
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• v.21 no.1
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• pp.39-46
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• 2005

The promoter region flanking the 5’ CAZFP1 coding region was isolated from the genomic DNA of Capsicum annuum. To identify the upstream region of the CAZFP1 gene required for promoter activity, a series of CAZFP1 promoter deletion derivatives was created. Each deletion construct was analyzed by Agrobacterium-mediated transient transformation in tobacco leaves after infection by Pseudomonas syringae pv. tabaci, or treatment with methyl jasmonate (MeJA), ethylene, abscisic acid (ABA), salicylic acid (SA), cold and wounding. Promoter fragments of 685 bp or longer showed 7-fold or greater induction after P. s. pv. tabaci infection and MeJA treatment. The CAZFP1 full-length promoter (-999 bp) also showed 6-fold induction in response to ethylene. The transiently transformed tobacco leaves with the CAZFP1 full length promoter fused-GUS gene showed more than 5-fold induction in response to SA, ABA and cold. These results suggest that the CAZFP1 promoter contains responsive elements for pathogen, MeJA, ethylene, SA, ABA and cold.

• Molecules and Cells
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• v.26 no.4
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• pp.368-372
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• 2008

Recent molecular and genetic studies in rice, a short-day plant, have elucidated both conservation and divergence of photoperiod pathway genes and their regulators. However, the biological roles of rice genes that act within the autonomous pathway are still largely unknown. In order to better understand the function of the autonomous pathway genes in rice, we conducted molecular genetic analyses of OsFVE, a rice gene homologous to Arabidopsis FVE. OsFVE was found to be ubiquitously expressed in vegetative and reproductive organs. Overexpression of OsFVE could rescue the flowering time phenotype of the Arabidopsis fve mutants by up-regulating expression of the SUPPRESSOR OF OVEREXPRESSION OF CO1 (SOC1) and down-regulating FLOWERING LOCUS C (FLC) expression. These results suggest that there may be a conserved function between OsFVE and FVE in the control of flowering time. However, OsFVE overexpression in the fve mutants did not rescue the flowering time phenotype in in relation to the response to intermittent cold treatment.

• Proceedings of the Microbiological Society of Korea Conference
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• 2001.11a
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• pp.138-145
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• 2001

The hydrophobic spores of Streptomyces sp. AA8321 isolated from the Antarctic coast displayed demulsification ability. The aerial spores demulsified an emulsion of kerosene/$0.2\%$ Triton X-100 (2:1, v/v) to $50\%$ and $95\%$ within 1 min contact at the concentrations of $5.0{\times}10^7$ and $1.0{\times}10^8$ spores/ml, respectively. A cold shock protein (csp) gene was cloned from the hydrophobic spore- producing Streptomyces sp. AA8321 using PCR. It encoded a low molecular protein with 68 amino acids showing very low homology with previously reported csp genes. Only the sequence of the first six amino acids was just the same and yet others were different. RNA blot analysis indicated that the csp gene was induced by cold shock, i.e., transferring from $30^{\circ}C$ to $10^{\circ}C$, and this cold shock response proposed that the isolated gene be a new type of csp gene.

• Journal of Microbiology and Biotechnology
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• v.32 no.6
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• pp.768-775
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• 2022

In this study we aimed to derive the response surface models for Escherichia coli reduction in wheat flour using atmospheric cold plasma (ACP) with three types of gas. The jet-type atmospheric cold plasma wand system was used with a 30 W power supply, and three gases (argon, air, and nitrogen) were applied as the treatment gas. The operating parameters for process optimization considered were wheat flour mass (g), treatment time (min), and gas flow rate (L/min). The wheat flour samples were artificially contaminated with E. coli at a concentration of 9.25 ± 0.74 log CFU/g. ACP treatments with argon, air, and nitrogen resulted in 2.66, 4.21, and 5.55 log CFU/g reduction of E. coli, respectively, in wheat flour under optimized conditions. The optimized conditions to reduce E. coli were 0.5 g of the flour mass, 15 min of treatment time, and 0.20 L/min of nitrogen gas flow rate, and the predicted highest reduction level from modeling was 5.63 log CFU/g.

• Journal of Ecology and Environment
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• v.31 no.4
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• pp.317-325
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• 2008

P. glehnii, an evergreen conifer found in northern areas, is known as a cold-resistant species. In this experiment, we measured the water content, PSⅡ efficiency, chlorophyll fluorescence, pigments of the xanthophyll-cycle and activity of enzymes of the ascorbate-glutathione cycle during cold acclimation and at subsequent low-temperature conditions to examine the importance of acclimation to cold tolerance. P. glehnii showed a decrease in PSⅡ efficiency (especially in Fv) during cold acclimation and at subsequent low temperatures. However, cold-acclimated needles showed higher PSⅡ efficiency at low temperatures than nonacclimated needles. In addition, 0-YON (first-year needles) showed an increase in $\beta$-carotene and lutein, while 1-YON (one-year-old needles) immediately developed an antioxidant mechanism in the ascorbate-gluthathione cycle as soon as they were exposed to low temperature and both 0-YON and 1-YON showed increased zeaxanthin and de-epoxidation ratios at continuous low temperature. Based on our results, we suggest that P. glehnii maintain PSⅡ efficiency at low temperature by effectively protecting the photosynthetic apparatus from photo-damage by rapid induction of an antioxidant mechanism in 1-YON and dissipation of excess energy by $\beta$-carotene and lutein in 0-YON.

• BMB Reports
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• v.40 no.6
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• pp.986-1001
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• 2007

Cold acclimation improves freezing tolerance in plants. In higher plants, many advances have been made toward identifying the signaling and regulatory pathways that direct the low-temperature stress response; however, similar insights have not yet been gained for simple nonvascular plants, such as bryophytes. To elucidate the pathways that regulate cold acclimation in bryophytes, we used two PCR-based differential screening techniques, cDNA amplified fragment length polymorphism (cDNA-AFLP) and suppression subtractive hybridization (SSH), to isolate 510 ESTs that are differentially expressed during cold acclimation in Physcomitrella patens. We used realtime RT-PCR to further analyze expression of 29 of these transcripts during cold acclimation. Our results show that cold acclimation in the bryophyte Physcomitrella patens is not only largely similar to higher plants but also displays distinct differences, suggests significant alteration during the evolution of land plants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.776-782
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• 2015

We examined the community structure of fish off the coast of Jindo Island in response to a cold water appearance in the southwestern sea of Korea each August between 2013–2015. Using a gape net with wings, we collected 31 taxa during the study period, wherein the most dominant species was Engraulis japonicus. Collichthys lucidus and Neosalanx andersoni, which are mainly distributed in the western sea of Korea, increased in abundance and were dominant in August 2013, possibly due to the apparent intrusion of cold water (< 19°C) from offshore into the coastal waters of Jindo Island. Meanwhile, Scomberomorus niphonius and Sardinella zunasi, which are known as warmwater migratory species, increased in abundance and were dominant in August 2015, likely influenced by the warmer water (> 20°C) at the coast, which resulted in a noticeable lessening of the cold water in the study area. However, no significant differences were observed in fish community structure in the month of August between 2013–1015. This implies that the small-scale spatial and temporal variations in the cold water had limited effects on the fish community structure, even though the abundances of several dominant species varied in the coastal waters.

• Journal of Microbiology and Biotechnology
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• v.30 no.11
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• pp.1777-1784
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• 2020

To increase the availability of microalgae as producers of valuable compounds, it is necessary to develop novel systems for gene expression regulation. Among the diverse expression systems available in microalgae, none are designed to induce expression by low temperature. In this study, we explored a cold-inducible system using the antifreeze protein (AFP) promoter from a polar diatom, Chaetoceros neogracile. A vector containing the CnAFP promoter (pCnAFP) was generated to regulate nuclear gene expression, and reporter genes (Gaussia luciferase (GLuc) and mVenus fluorescent protein (mVenus)) were successfully expressed in the model microalga, Chlamydomonas reinhardtii. In particular, under the control of pCnAFP, the expression of these genes was increased at low temperature, unlike pAR1, a promoter that is widely used for gene expression in C. reinhardtii. Promoter truncation assays showed that cold inducibility was still present even when pCnAFP was shortened to 600 bp, indicating the presence of a low-temperature response element between -600 and -477 bp. Our results show the availability of new heterologous gene expression systems with cold-inducible promoters and the possibility to find novel low-temperature response factors in microalgae. Through further improvement, this cold-inducible promoter could be used to develop more efficient expression tools.

• Industrial Engineering and Management Systems
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• v.13 no.4
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• pp.421-431
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• 2014

The market basket data in the form of a binary user-item matrix or a binary item-user matrix can be modelled as a binary classification problem. The binary logistic regression approach tackles the binary classification problem, where principal components are predictor variables. If users or items are sparse in the training data, the binary classification problem can be considered as a cold-start problem. The binary logistic regression approach may not function appropriately if the principal components are inefficient for the cold-start problem. Assuming that the market basket data can also be considered as a special regression problem whose response is either 0 or 1, we propose three supervised learning approaches: random forest regression, random forest classification, and elastic net to tackle the cold-start problem, comparing the performance in a variety of experimental settings. The experimental results show that the proposed supervised learning approaches outperform the conventional approaches.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.2
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• pp.22-30
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• 2003

Engine-out HC emissions were investigated during cold and hot start. The tests were conducted according to engine cooling temperatures which were controlled by simulated coolant temperatures of cold and hot start, on a 1.5L, 4-cylinder, 16 valve, multipoint-port-fuel-injection gasoline engine. Real time engine-out HC emissions were measured at a exhaust port and cylinder head using Fast Response Flame Ionization Detector(FRFID). Unburned hydrocarbons emitted at the cold coolant temperature were much higher than those of the hot coolant temperatures. And the main source of the high HC emission was confirmed as misfire at cold coolant temperature. In addition, the effect of intake valve timing on engine-out HC emissions was investigated. The results obtained indicate that optimized intake phasing provides the potential for start-up engine-out HC emissions reduction.