• Journal of Life Science
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• v.25 no.4
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• pp.385-389
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• 2015

In this study, it is reported that a large polyprotein can be stoichiometrically cleaved by the use of caspase-3-dependent proteolysis. Previously, it has been shown that the proteolytic IETD motif was partially processed when treated with caspase-3, while the DEVD motif was completely cleaved. The cleavage efficiency of the DEVD-based substrate was approximately 2.0 times higher than that of the IETD substrate, in response to caspase-3. Based on this, 3 protein genes of interest were genetically linked to each other by adding two proteolytic cleavage sequences, DEVD and IETD, for caspase-3. Particularly, glutathione-S transferase (GST), maltose binding protein (MBP), and red fluorescent protein (RFP) were chosen as model proteins due to the variation in their size. The expressed polyprotein was purified by immobilized metal ion affinity chromatography (IMAC) via a hexa-histidine tag at the C-terminal end, showing 93 kDa of a chimeric GST:MBP:RFP fusion protein. In response to caspase-3, cleavage products, such as MBP:RFP (68 kDa), MBP (42 kDa), RFP (26 kDa), and GST (25 kDa), were separated from a large precursor GST:MBP:RFP (93 kDa) via SDS-PAGE. The results obtained from this study indicate that a multi-protein can be stoichiometrically produced from a large poly-protein by using proteolytic recognition motifs, such as DEVD and IETD tetra-peptides, for caspase-3.

• Research in Plant Disease
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• v.14 no.1
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• pp.64-67
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• 2008

In 2005 and 2007, petiole and root rot of Spathiphyllum spp. was occurred at commercial greenhouse during summer (June-September) in Koyang city and Yongin city, Kyunggi-do, Korea. The pathogenic fungus was isolated from diseased plants and the cultural and morphological chracteristic were observed. Conidia were rod in shape, 1-3 septa and $67.5-95.0{\times}4.8-6.5\;{\mu}m$ (av. $82.0{\times}6.0\;{\mu}m$) in size. The optimum temperature for the mycelial growth of the isolates was $27^{\circ}C$. According to result the pathogenicity test, first disease symptoms appeared five days after inoculation. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Cylindrocladium spathiphylli. This is the first report on Spathiphyllum spp. caused by C spathiphylli in Korea.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.601-606
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• 2023

The edible sweetener aspartame is formed from the synthesis of asparagine, one of the amino acids, and phenylalanine. It is a protein ingredient that produces sweetness 200 times higher than sucrose, and is used as a diet product because it is a substance that can replace sugar. Although the effects on animals and humans have been well studied, no studies have been conducted on plant metabolism. In this study, the effect of aspartame metabolism was tested using germinated onion, bean sprouts, and Kalanchoe. The three types of plants with germinated roots showed rapid growth in the early stage of treatment with 1mM aspartame, and showed a nutrient supply effect due to the effect of amino acids, which are constituents. However, when treated for 4 weeks, symptoms similar to lateral roots appear in the form of lignification in onions, the effect of quickly withering is seen in bean sprouts, and senescence of roots appears in 12-week-old Kalanchoe. All of them show accelerated aging after the growth phase. This shows that, among the two amino acids, asparagine is related to auxin generation that induces rapid growth, and it is thought to be the result of lignification due to the effect of phenylalanine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1304-1316
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• 2014

The aims of this study were to estimate daily intakes of artificial sweeteners from beverages and liquid teas as well as evaluate their potential health risks in Korean children and adolescents (1 to 19 years old). Dietary intake assessment was conducted using actual levels of aspartame, acesulfame-K, and sucralose in non-alcoholic beverages (651 beverages and 87 liquid teas), and food consumption amounts were drawn from "The Fourth Korea National Health and Nutrition Examination Survey (2007~2009)". To estimate dietary intake of non-alcoholic beverages, a total of 6,082 children and adolescents (Scenario I) were compared to 1,704 non-alcoholic beverage consumption subjects (Scenario II). The estimated daily intake of artificial sweeteners was calculated based on point estimates and probabilistic estimates. The values of probabilistic artificial sweeteners intakes were presented by a Monte Carlo approach considering probabilistic density functions of variables. The level of safety for artificial sweeteners was evaluated by comparisons with acceptable daily intakes (ADI) of aspartame (0~40 mg/kg bw/day), acesulfame-K (0~15 mg/kg bw/day), and sucralose (0~15 mg/kg bw/day) set by the World Health Organization. For total children and adolescents (Scenario I), mean daily intakes of aspartame, acesulfame-K, and sucralose estimated by probabilistic estimates using Monte Carlo simulation were 0.09, 0.01, and 0.04 mg/kg bw/day, respectively, and 95th percentile daily intakes were 0.30, 0.02, and 0.13 mg/kg bw/day, respectively. For consumers-only (Scenario II), mean daily intakes of aspartame, acesulfame-K, and sucralose estimated by probabilistic estimates using Monte Carlo simulation were 0.52, 0.03, and 0.22 mg/kg bw/day, respectively, and 95th percentile daily intakes were 1.80, 0.12, and 0.75 mg/kg bw/day, respectively. For scenarios I and II, neither aspartame, acesulfame-K, nor sucralose had a mean and 95th percentile intake that exceeded 5.06% of ADI.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.2
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• pp.134-140
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• 2011

Recent work in compressed sensing theory shows that $M{\times}N$ independent and identically distributed sensing matrix whose entries are drawn independently from certain probability distributions guarantee exact recovery of a sparse signal with high probability even if $M{\ll}N$. In particular, it is well understood that the $L_1$-minimization algorithm is able to recover sparse signals from incomplete measurements. In this paper, we propose a novel sparse signal reconstruction method that is based on the reweighted $L_1$-minimization via support detection.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.162-167
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• 1992

Tic and TiN layers were deposited on the stainless steel substrate by the reactive RF sputtering. Ar was used for sputtering gas and CzHz and Nz were used for reaction gas. Deposition rate increased linearly to the applied RF power, and decreased as the partial pressure ratio of sputter gas to reactive gas increased. The thin layers were stoichiometric at the partial pressure ratio of 0.03 for Tic and at partial pressure ratio of 0.05 for TiN. The morphologies and structures of the thin layers were investigated by AES, SEM and TEM. In addition, N+ ion was implanted to Tic and the resulting influence on the film and annealing effects were also examined.

• Korean Journal of Materials Research
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• v.2 no.5
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• pp.337-342
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• 1992

Spectroscopic diagnostics on reactive plasmas was carried out in a facing target sputtering unit with BaO +12Fe composite targets and 50% $O_2+$ Ar sputter gas. Spectra of rective plasmas were composed of peaks which were assigned to be Ba, B$a^+$, Fe, FeO, F$e^+$, Ar, $Ar^+$, O, $O^+$. As detecting positions in plasmas were far away from targets, the relative peak intensities of the ions and neutral species were decreased, but the relative intensities of the former decreased faster than those of the latter.

• Parasites, Hosts and Diseases
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• v.28 no.1
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• pp.1-10
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• 1990

To establish an animal model of intracranial sparganosis, the fate and behavior of the experimentally inoculated spargana were observed. A total of 102 scolices of spargana were injected into 22 cat brains, and the cats were sacrificed at 2 weeks, 1 month, 3 months and 6 months after the inoculation. Neurosparganosis was established in 77% of the cats. Of 43 recovered worms,19 (44%) were located in the subdural or subarachnoid space,16 (37%) in the brain Parenchyme, and 2 (5%) in the lateral ventricle. One was detected at the diploic space of the skull and 5 were outside the cranial cavity. All but one were alive, and had grown tails. They were distributed in the brain parenchyme randomly. There was no place which they could not invade. No adult was found in the intestine. Cerebrospinal fluid (CSF) was collected before inoculation, 1 week, 2 weeks, 1 month, 3 months and 6 months after inoculation. The level of anti-sparganum IgG antibody in CSF measured by ELISA began to increase above the criteria of positivity 1 month after inoculation. Three months after inocula- tion, the values markedly increased. The present findings reveal that intracranial inoculation of spargana into the brains of cats would be a good animal model of experimental neurosparganosis.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.44-49
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• 2001

To study whether the secondary toxic substances such as ethylene and reactive oxygen species(ROS) are induced by air pollutants in foliage plants, $SO_2$ was fumigated to Pachira aquatica, Spathiphyllum patinii, and Hedera helix. $SO_2$ was controlled to $1\;{\mu}L/L$ and then fiumigated to plants for 2 days(8 hrs/day). It resulted in visible injury in P. aquatica and H. helix while no symptom appeared in S. patinii. Photosynthetic rate and water use efficiency were most remarkably reduced in P. aquatica compared to other two species whereas least in S. patinii. Two days after $SO_2$ fumigation, ethylene evolution was quantified to 23.56, 10.43 and 4.79 nL/g/h in P. aquatica, H. helix and S patinii, respectively. On the other hand, antioxidative enzymes were clearly activated by $SO_2$ treatment in all tested plant species implying ROS production. In conclusion, we could suggest that ethylene and ROS have been intimately related to the defense mechanism against $SO_2$ and their induction degree increased with plant susceptibility to $SO_2$. Furthermore, it was found that S. patinii was tolerant and P. aquatica sensitive to $SO_2$ on the basis of antioxidative enzyme activity and ethylene evolution.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.162-168
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• 1996

Effects of temperature, pH and addition of NaCl and quinine on sweetness and recognition threshold of aspartame were investigated. Changes in flavor of some foods were also studied when aspartame was added. The sweetness of 0.02% aspartame, the equi-sweetness of 4.3% sugar, was organoleptically evaluated by multiple comparison test at variouse range of temperature ($4^{\circ}$, $20^{\circ}$, $40^{\circ}$, $60^{\circ}$ and $80^{\circ}C$), pH (3.0, 4.5, 6.0 and 7.5), NaCl (0.5, 1.0, 1.5 and 2.0%) and quinine (0.001, 0.003 and 0.005%). The highest sweetness was obtained at $20^{\circ}C$ and pH 3.0-4.5. Addition of NaCl at 0.5% level showed the highest sweetness which was decreased thereafter. The sweetness was significantly decreased by the addition of quinine. The recognition threshold of aspartame was the lowest at $20^{\circ}C$ and pH 3.0-4.5. Lower in bitterness and higher In ginseng flavor were noted in ginseng tea with aspartame than in that without aspartame. Improved roasted flavor and decreased undesirable odor and taste were resulted in soymilk with the addition of aspartame. The flavors of orange, apple and strawberry were enhanced by aspartame in orange juice, apple juice and strawberry juice, respectively.