• Journal of The Korean Astronomical Society
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• v.43 no.1
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• pp.9-23
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• 2010

In this paper we examined the association of Infrared Dark Cloud (IRDC) cores with YSOs and the geometric properties of the IRDC cores. For this study a total of 13,650 IRDC cores were collected mainly from the catalogs of the IRDC cores published from other studies and partially from our catalog of IRDC cores containing new 789 IRDC core candidates. The YSO candidates were searched for using the GLIMPSE, MSX, and IRAS point sources by the shape of their SED or using activity of water or methanol maser. The association of the IRDC cores with these YSOs was checked by their line-of-sight coincidence within the dimension of the IRDC core. This work found that a total of 4,110 IRDC cores have YSO candidates while 9,540 IRDC cores have no indication of the existence of YSOs. Considering the 12,200 IRDC cores within the GLIMPSE survey region for which the YSO candidates were determined with better sensitivity, we found that 4,098 IRDC cores (34%) have at least one YSO candidate and 1,072 cores among them seem to have embedded YSOs, while the rest 8,102 (66%) have no YSO candidate. Therefore, the ratio of [N(IRDC core with protostars)]/[N(IRDC core without YSO)] for 12,200 IRDC cores is about 0.13. Taking into account this ratio and typical lifetime of high-mass embedded YSOs, we suggest that the IRDC cores would spend about $10^4\sim10^5$ years to form high-mass stars. However, we should note that the GLIMPSE point sources have a minimum detectable luminosity of about $1.2 L_{\odot}$ at a typical IRDC core's distance of ~4 kpc. Therefore, the ratio given here should be a 100ver limit and the estimated lifetime of starless IRDC cores can be an upper limit. The physical parameters of the IRDC cores somewhat vary depending on how many YSO candidates the IRDC cores contain. The IRDC cores with more YSOs tend to be larger, more elongated, and have better darkness contrast than the IRDC cores with fewer or no YSOs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.834-840
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• 2008

In order to improve the use of pumpkin seed, the present study was performed to isolate compositions of the bitter components which were not seen in pumpkin seed itself but newly biosynthesized during germination of the seed. The compositions isolated were then further purified by TLC and preparative HPLC in which a fraction with Rf 0.73 and RT 10.3 was obtained. Cucurbitacin E with molecular weight of 557 from the fraction was finally identified by subsequent structural analysis of LC-MS/MS. The production of cucurbitacin E peaked with 224.7 mg/kg at 4 days of germination at $20^{\circ}C$ with the water supply at ntervals of 48 hrs in the darkness, while that of cucurbitacin E reached 146.7 mg/kg in the brightness. In vitro-cell based assays demonstrated that the isolated and purified cucurbitacin E inhibited proliferation of A549 lung cancer cells and suppressed expression of the IL-$1{\beta}$- or PMA-induced cyclooxygenase-2, an inflammatory protein in A549 cells, suggesting its anti-proliferative and anti-inflammatory activities.

• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.18-24
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• 2000

Pepper (Capsicum annum L.) used as a spice or fruit vegetable has been transplanted for cultivation to accompany the production of its seedlings in general. The experiment was done to measure the effect of its cultivars (Daemyng; Wanggochu), priming (chemicals; concentration; period), light quality (red; far-red; blue; dark) during priming, and germination temperature (25 or 15$^{\circ}C$ constant; 25/15$^{\circ}C$ alternating) on the rate of germination done under incandescent lamps until 9 days after sowing. Seed germination was better when primed with Ca(NO$_3$)$_2$ than with KNO$_3$. Priming for 6 to 12 days using the former chemical enhanced the final germination rate and shortened the elapsed days to 50% germination, $T_{50}$, compared to no-priming. Under $25^{\circ}C$ constant germination temperature, primed seeds at darkness or far-red light showed the highest rate until 5 days after sowing or the lowest one since 7 days after sowing, respectively. The germination response at 25/15$^{\circ}C$ alternating temperature did not followed the lowest rate of 15$^{\circ}C$ constant germination temperature but inclined to that of $25^{\circ}C$ constant recorded the greatest one. Under 3 germination temperature red light treated during priming elevated the rate since 7 days after sowing compared to the other light treatments, and the germination rate of each cultivar was affected by no-priming or priming, light quality during priming. which imply their interaction to the seed germination.

• Journal of Aquaculture
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• v.6 no.3
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• pp.159-171
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• 1993

The effects of environmental factors (density, light, temperature) and live food on growth and survival rate of zoea and mysis of fleshy shrimp, Penaeus chinensis, were examined. The percent survival rates at the culture densities of 200 and 300 larvae per liter were significantly higher than that of 500 larvae per liter (p< 0.05). The percent survival rates at the culture densities of 100, 200, 300 and 500 larvae per liter were $90.3^{ab},\;95.2^a,\;94.3^a\;and\;86.7^b\%$ (p< 0.05). The effects of light conditions with diatom premix diet showed that continuous light was the best for the survival rate, $96.5\%$. Natural light and continuous darkness showed the survival rates $79.0\%\;and\;4.3\%$, respectively. On the rearing temperature, the survival rates were $97.3\%\;at\;19^{\circ}C\;and\;96.7\%\;at\;22^{\circ}C$ with little difference but the higher temperature resulted in faster growth. The survival rate was $51.6\%;at\;25^{\circ}C$ thus showing significant decrease compared to $19^{\circ}C\;and\;22^{\circ}C$. At this temperature the growth was also suffered. With regard to dietary value of live food, both the best survival rate and the fastest growth were obtained when 6 mixed species of diatom (A. normaii, C. simplex, N closterium, P. tricornutum, S. costatum and T. weissflogii) were provided. When single species was supplied the best survival rate $(82.1\%)$ was obtained with S. costatum, but the other species resulted in much inferior survival rates $(below\;80.0\%)$ and poor growth.

• Korean Journal of Plant Tissue Culture
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• v.28 no.6
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• pp.297-304
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• 2001

Scrophularia buergeriana Misrule has been contaminated with various pathogens in condition of field and storage period. This study was carried out for production of multiple stress resistance plant containing disease resistance that CGST gene expressed in transgenic Scrophularia buergeriana Misrule genome. Glutathione S-Transferases (GSTs) detoxify endobiotic and xenobiotic compounds by covalent linking of tripeptide glutathione to hydrophobic substrate. GST enzymes have been identified and characterized in insects, bacteria, and many plant species. A cDNA clone of GST was introduced into Scrophularia buergeriana Miquel by transformation with Agrobacterium tumefaciences. In coporation of the CGST gene into S. buergeriana Misrule was confirmed by PCR analysis of genomic DNA. Influence of exposure to darkness on the regeneration potential and transformation frequence were assessed. The activity of GST in transgenic plants was two times higher than that of non-transgenic plants. As a result of anti-microbe assays, the crude extract protein of transgenic plants showed the antimicrobial effects higher than control plants.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.3
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• pp.351-357
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• 2011

An experiment was conducted to evaluate the effects of castration on growth performance, carcass characteristics, and meat quality of goat kids. Fourteen Boer-cross buck and wether goat kids (n = 7; initial body weight (BW) $38.0{\pm}0.35\;kg$ and $34.8{\pm}0.35\;kg$, for bucks and wethers, respectively) were grazed on annual Marshall ryegrass (Lolium multiflorum Lam.) for 56 days. Body weights were recorded after 4 h withdrawal from feed and water for two consecutive days, every 2 wk. After d 56, animals were harvested and hot carcass weight (HCW), cold carcass weight (CCW), dressing percent (DP), kidney and pelvic fat (KPF), longissimus muscle (LM) area, back fat (BF), and other carcass parameters were measured. Day 0 BW was used as a covariate for analyses. However, bucks were heavier than wethers at d 15 (p = 0.09), 42 (p = 0.001) and 56 (p = 0.001). Bucks had higher ADG (146 vs. 74 g/d; p = 0.001), HCW (21.2 vs. 18.8 kg; p = 0.06) and CCW (20.3 vs. 17.9 kg; p = 0.04) when compared with wether goats. Dressing percentage (51 vs. 47%; p = 0.06), KPF (0.44 vs. 0.16%; p = 0.02) and BF (0.41 vs. 0.21 cm; p = 0.05) were higher in wethers vs bucks, respectively; however, USDA live or carcass grades were similar. Longissimus muscle tissue from wethers and bucks were similar in darkness ($L^*$) and redness ($a^*$), but wethers had more (p = 0.02) yellow tint ($b^*$). Palmitic (C16:0), stearic (C18:0) and oleic (C18:1) acids were higher (p = 0.001) in muscle tissue from wethers compared to bucks. The saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) contents of muscle tissue were lower (p = 0.001) for bucks with no difference in polyunsaturated fatty acids (PUFA). Longissimus muscle initial temperature was higher in bucks (p<0.04) and pH change post-mortem was similar for bucks and wethers. These results indicated that castration of young market goats reduced growth performance and produced carcasses with more fat and higher SFA.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.336-342
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• 1994

Changes in physicochemical characteristics were investigated for immature barley kernels roasted at $160{\sim}220^{\circ}C$ for $1{\sim}12$ min. Only small differences in chemical constituents including starch, protein, fat, ash, total dietary fiber, and ${\beta}-glucan were observed between immature and mature barley kernels. The amounts of 75% ethanol-soluble sugars and amino acids present in immature barley kernels were considerably higher than those in mature kernels, and gradually decreased in the process of roasting. Of free sugars, sucrose, raffinose, glucodifructose($GF_{2}$) and maltose were reduced by roasting. Glucose and fructose, simple reducing sugars, decreased at the early stage of roasting, followed by a slight increase at the later stage. Starch and nitrogen contents decreased slowly, while TDF(total dietary fiber) had a tendency to increase slightly. Stacking volume of immature barley kernels increased markedly, especially at the higher temperatures. L value of immature barley decreased throughout roasting, and a, b values increased at the early stage of roasting but b value decreased with continued roasting. The degree of roasting was strongly affected by the roasting temperature. Darkness of immature barley kernel, depending on the degree of roasting, was highly associated with concentrations of brown pigments extracted from roasted immature barley kernels.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.556-561
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• 1995

Persisent circadian rhythms in carbon assimilation, stomatal conductance and soluble carbohydrate concentration were investigated during grain filling period in rice plant transferred from a natural photoperiod to constant conditions. A weak rhythm in photosynthesis, measured as carbon assimilation, and stomatal opening, as conductance to water vapor, with a period of approximately 24-hours, occurred under constant condition. Carbon assimilation and stomatal conductance reached maximum values near noon and minimum values near midnight during the early stage (until 72-hour) after transferring to constant condition, and then the amplitude and phase were changed slowly, the rhythms with little damping, reaching maximum values near midnight and minimum values near noon during 96~120-hours after transferring. However, photosynthesis in plants grown for 14days after anthesis under constant moderate light(day and night) did not oscillated in constant condition unlike plants grown under a cycle of light and darkness. These phenomenon was observed in soluble carbohydrate concentration in flag leaves as well. Evidences from several approaches indicate that endogenous rhythms of $CO_2$ assimilation, stomatal conductance and soluble carbohydrate concentration are closely couped with each other and particularly important to plants, which depend on the natural day-night cycle as a external signal.

• Journal of Bio-Environment Control
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• v.10 no.3
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• pp.159-164
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• 2001

This study were conducted to investigate the influence of chilling on photosynthetic rate, root activity, contents of total sugars and fatty acids of cucumber seedlings grown in a greenhouse. Even though photosynthetic activity of seedlings exposed to $0^{\circ}C$ for 5 hours was little or insignificantly influenced, it was reduced by 52.8% and 67.7% in seedlings exposed to the same temperature for an extended 10 and 24 hours, respectively. Photosynthetic rate decreased significantly when seedlings were illuminated, as compared to continuously held under darkness, during 15 hours of chilling treatment at 3$^{\circ}C$. Recovery of photosynthetic ability was also retarded by illumination during a recovery period after chilling treatment. Root activity, as measured by the oxidation power of $\alpha$-naphtylamine, was significantly reduced by chilling treatment at 0 to 6$^{\circ}C$, but amount of bleeding xylem sap collected at 40 days after chilling treatment was not significantly different among treatments. Total sugar content increased by 12 and 23% as compared to the control in seedlings chilled for 24 hours, respectively, at 3$^{\circ}C$. Contents of unsaturated linolenic and oleic acids increased, while content of saturated palmitic acid decreased with chilling treatment.

• Journal of Bio-Environment Control
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• v.10 no.3
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• pp.165-171
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• 2001

This study was conducted to investigate the influence of light condition before and after chilling treatment started at different times of a day on the survival and physiological responses of cucumber seedlings grown in a greenhouse. Percent survival of cucumber seedling exposed to a chilling temperature of 2$^{\circ}C$ for 48 hours varied considerably depending upon the initiation time of chilling treatment. Seedlings exposed to chilling treatment from 7:00 o clock, the end of a dark period, showed considerably lower % survival of 30.6% as compared to 90.2% in those exposed to the same treatment starting from 18:00 o clock, the end of a photoperiod. This difference in % survival was found to be closely associated with content of photosynthetic assimilates in seedlings. Relative amount of electrolyte leakage was 57.1% in seedlings chilled from 7:00 o clock and 25.9% in seedlings chilled from 18:00 o clock. Among the ions found in the electrolyte leakage, content of $K^{+}$ was the greatest, followed by that of N $a^{+}$, $Mg^{+}$ and $Ca^{+2}$. Light illumination for 2 hours or longer shortly before chilling treatment during the dark period was effective in increasing % survival of seedlings, probably because of increased photosynthetic assimilates in seedlings. Light illumination during a 48 hour chilling treatment at 3$^{\circ}C$ significantly reduced % survival to 43.3% as compared to 92.0% in seedlings kept continuously in darkness.ess.s.