• Journal of Family Resource Management and Policy Review
• /
• v.25 no.3
• /
• pp.103-120
• /
• 2021

Recently, the importance of the fathers role in the care of young children has been emphasized in Korea for the balance of childcare responsibilities between mothers and fathers. This study investigates the trends in paternal childcare in Korea over the last 15 years. Childcare is divided into primary and developmental care and fathers's Childcare time and participation rates are inverstigated for dual- and single-income households. Data are collected from the four waves of the five-yearly Statistics of Korea Life Time Surveys between 2004(t₁) and 2019(t₄) including the workday time diaries of fathers with preschool children(n₁=2,264, n₂=1,242, n₃=959, n₄=952). Three major results are identified. First, paternal childcare time and participation rates have increased with dual-income fathers spending 24 more minutes a day with their young child(ren) in 2019 than in 2004, which is nearly double. Second, in the analysis of fathers' childcare time use and participation rates comparing primary and developmental care, primary care is found to have increased more than developmental care, especially among dual income fathers: this further exhibits a reversed relation between primary and developmental care over time. Third, the determinants of paternal childcare time are fathers' age, market labor time, commuting time, gender equality consciousness, and education. In particular, market labor time was significant in all four waves, while gender equality consciousness is only significant for single-income fathers. Based on these results, a specific agenda is provided for family-friendly policies to improve the balance of childcare roles between fathers and mothers, especially encouraging increased(significant and sufficient) participation of fathers in primary care activities.

• Journal of Bio-Environment Control
• /
• v.30 no.4
• /
• pp.429-440
• /
• 2021

During the growing period, the integrated solar radiation inside the greenhouse was 12.7MJ·m^-2d^-1, and which was 90% of the average daily global radiation outside the greenhouse, 14.1MJ·m^-2d^-1. The 24-hour average temperature inside the greenhouse from July to August, which has the highest temperature of the year, was 3.04℃ lower than the outside temperature, and 4.07℃ lower after the rainy season. Before the operation of fog cooling system, the average daily RH (%) was lowered to a minimum of 40% (20% for daytime), making it inappropriate for paprika cultivation, but after the operation of fog system, the daily RH during the daytime increased to 70 to 85%. The average humidity deficit increased to a maximum of 12.7g/m³ before fog supply, but decreased to 3.7g/m³ between July and August after fog supply, and increased again after October. The daytime residual CO₂ concentration inside the greenhouse was 707 ppm on average during the whole growing period. The marketable yield of paprika harvested from July 27th to November 23rd, 2020 was higher in 'DSP-7054' and 'Allrounder' with 14,255kg/10a and 14,161kg/10a, respectively, followed by 'K-Gloria orange', 'Volante' and 'Nagono'. There were significant differences between paprika cultivars in fruit length, fruit diameter, soluble solids (°Brix), and flash thickness (mm) of paprika produced in summer season at large single-span plastic greenhouse. The soluble solids content was higher in the orange cultivars 'DSP-7054' and 'Naarangi' and the flesh thickness was higher in the yellow and orange cultivars, with 'K-Gloria orange' and 'Allrounder' being the thickest. The marketable yield of paprika, which was treated with cooling and heating treatments in the root zone, increased by 16.1% in the entire cultivars compared to the untreated ones, increased by 16.5% in 'Nagano', 10.3% in the 'Allrounder', 20.2% in the 'Naarangi', and 17.3% in 'Raon red'.

• Korean Journal of Food Science and Technology
• /
• v.53 no.5
• /
• pp.640-647
• /
• 2021

In this study, we analyzed three rice pre-treatment methods for the preparation of mit-sool (first mashing), with godubap (steamed rice), beombeok (undercooked porridge), and juk (porridge). The results can provide basic data for the development of takju with improved quality. In terms of the base alcohol, godubap produced the highest amount of alcohol (8.1%) after two days, followed by beombeok and juk. After two days of fermentation, soluble solids were measured at 15.3, 15.1, and 1.4°Brix in beombeok, juk, and godubap, respectively, The glucose content of godubap did not change significantly; however, the maltose content increased. In beombeok, maltose decreased from 16.48 mg/mL on the initial day 0 to 1.27 mg/mL on day 9. In juk, glucose and maltose increased from 14.05 and 11.49 mg/mL on day 0 to 31.39 and 42.53 mg/mL on day 2, respectively. Succinic acid levels increased in the godubap and beombeok mit-sool. However, succinic acid was not detected in godubap and juk during the initial stage of fermentation, and lactic acid was not detected in beombeok mit-sool. During the fermentation stage of deot-sool (second mashing), the highest alcohol content of takju made with godubap alcohol was 18.0% and the lowest alcohol content was 15.1% in beombeok on day 9. The total acidity was as high as 0.54% for beombeok, 0.41% for juk, and 0.39% for godubap. In the flavor analysis, ethyl caprate and ethyl caprylate, which were high on day 0 in godubap, decreased upon the completion of fermentation on day 9. Banana-flavored isoamyl alcohol content increased. For juk, ethyl caprate and ethyl caprylate, which were high on day 0, decreased on day 9. Flavor components, such as ethyl palmitate and ethyl linoleate were increased.

• Journal of Life Science
• /
• v.29 no.4
• /
• pp.410-420
• /
• 2019

Citrus unshiu peel extracts possess a variety of beneficial effects, and studies on their anticancer activity have been reported. However, the exact mechanisms underlying this activity remain unclear. In the current study, the apoptotic effect of ethanol extract of C. unshiu peel (EECU) on human breast adenocarcinoma MDA-MB-231 cells and related mechanisms were investigated. The results showed that the survival rate of MDA-MB-231 cells treated with EECU was significantly inhibited in a concentration-dependent manner, which was associated with the induction of apoptosis. EECU-induced apoptosis was associated with the activation of caspase-8 and caspase-9, which initiate extrinsic and intrinsic apoptosis pathways, respectively, and caspase-3, a representative effect caspase. EECU suppressed the expression of the inhibitor of apoptosis family of proteins, leading to an increased Bax/Bcl-2 ratio and proteolytic degradation of poly (ADP-ribose) polymerase. EECU also enhanced the loss of the mitochondrial membrane potential and cytochrome c release from the mitochondria to the cytosol, along with truncation of Bid. In addition, EECU activated AMP-activated protein kinase (AMPK), and compound C, an AMPK inhibitor, significantly weakened EECU-induced apoptosis and cell viability reduction. Furthermore, EECU promoted the generation of reactive oxygen species (ROS), which acted as upstream signals for AMPK activation as pretreatment of cells, with the antioxidant N-acetyl cysteine reversing both EECU-induced AMPK activation and apoptosis. Collectively, these findings suggest that EECU inhibits MDA-MB-231 adenocarcinoma cell proliferation by activating intrinsic and extrinsic apoptotic pathways, which was mediated through ROS/AMPK-dependent pathways.

• Journal of Nutrition and Health
• /
• v.52 no.4
• /
• pp.399-407
• /
• 2019

Purpose: This study was conducted to evaluate the physicochemical properties of different batches of Saururus chinensis using different roasting temperature that were dried at different using different roasting temperatures and their were determined the antioxidative activities of water and 70% ethanol extracts. Methods: Extracts were examined for the total phenolic acid content, the and flavonoids contents and the antioxidant properties, including DPPH radical scavenging activity, ABTs scavenging activity and, the reducing power. Results: Moisture content was significantly higher in the LSC and the crude ash content was significantly higher in the HSC. The crude protein content was higher in the LSC (although not significantly), and the crude fat and carbohydrate contents were higher in the HSC (although not significantly). The total phenolic content was lower in the samples extracted with water, but there was no significant difference. However, the extracts extracted with 70% ethanol at a high drying temperature were significantly higher. The low temperature and high drying temperature batches of Saururus chinensis were significantly higher in the samples extracted with 70% ethanol than those extracted with 70% ethanol. The total phenolic acid content, the total flavonoid content and the electron donating ability were highest in the ethanol extract of Saururuschinensis treated at a high temperature. However, the ABTs radical activity was highest in the water extracted, high-temperature treated Saururuschinensis. The 70% ethanol extract of high temperature roasted Saururuschinensis had the highest antioxidative activities of all the Saururuschinensis batches. Conclusion: The total phenolic acid contents, total flavonoid contents, electron donating activity and reducing power activity were highest in all the 70% ethanol extraction batches of the high-temperature treated samples.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.20 no.4
• /
• pp.296-304
• /
• 2018

The objective of this study was to analyze the impact of climate change on rice yield and quality. Experiments were conducted using SPAR(Soil-Plant-Atmosphere-Research) chambers, which was designed to create virtual future climate conditions, in the National Institute of Crop Science, Jeonju, Korea, in 2016. In the future climate conditions($+2.8^{\circ}C$ temp, 580 ppm $CO_2$) of year 2051~2060 according to RCP 8.5 scenario, elevated temperature and $CO_2$ accelerated the heading date by about five days than the present climate conditions, resulted in a high temperature environment during grain filling stage. Rice yield decreased sharply in the future climate conditions due to the high temperature induced poor ripening. And the spikelet numbers, ripening ratio, and 1000-grain weight of brown rice were significantly decreased compared to control. The rice grain quality was also decreased sharply, especially due to the increased immature grains. In the future climate conditions, expression of starch biosynthesis-related genes such as granule-bound starch synthase(GBSSI, GBSSII, SSIIa, SSIIb, SSIIIa), starch branching enzyme(BEIIb) and ADP-glucose pyrophosphorylase(AGPS1, AGPS2, AGPL2) were repressed in developing seeds, whereas starch degradation related genes such as ${\alpha}-amylase$(Amy1C, Amy3D, Amy3E) were induced. These results suggest that the reduction in yield and quality of rice in the future climate conditions is likely caused mainly by the poor grain filling by high temperature. Therefore, it is suggested to develop tolerant cultivars to high temperature during grain filling period and a new cropping system in order to ensure a high quality of rice in the future climate conditions.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.63 no.4
• /
• pp.294-303
• /
• 2018

To set an optimal harvest time for five main whole-crop silage (WCS) rice cultivars, Nokyang (Ny), Mogwoo (Mw), Mogyang (My), Nokwoo (Nw) and Yeongwoo(Yw), based on feed value and dry matter yield, we analyzed water content (WC), feed values such as percent crude protein (CP), crude fat (CF), crude ash (CA), neutral detergent fiber (NDF), acid detergent fiber (ADF), estimated total digestible nutrients (TDN), and calculated their dry matter yield (DMY). These parameters were estimated at the booting stage and every 10 days from start of heading to 45 days after heading (DAH) to identify the optimal harvest time for these rice varieties. In all varieties, except Ny, the WC was about 65% on the $30^{th}$ DAH. In terms of WC, it is judged that there would be no major problem in preparing high quality silage when harvested between 20~30 DAH for Ny and about 30 days for the other cultivars. The CP and CA decreased significantly as the harvest time was delayed in all varieties (p<0.05). However, the CF in the tested varieties generally declined as DAH increased, and then increased again(p<0.05). The decrease in ADF and NDF was significantly different from the booting stage to 45 DAH in all varieties (p<0.05) and the estimated TDN increased gradually in all varieties as the harvest time was delayed. The TDN of all varieties, except Nw, was over 70% around 30 DAH. As harvest time was delayed, the DMY for all WCS rice increased significantly (p<0.05). The maximum DMY for each cultivar was observed at 45 DAH, however, no significant difference (p<0.05) was seen after 40 DAH for Ny and Yw, 30 DAH for Mw and Nw, and 20 DAH for My. Considering these results and others factors such as lodging, shattering, digestibility of grains, conversion of eating rice, etc., the optimal harvest time for silage use of all WCS rice tested was generally the yellow ripening stage, at about 30 DAH (30~40 DAH for Ny and Mw, and 30 DAH for My, Nw and Yw).

• Journal of Food Hygiene and Safety
• /
• v.34 no.4
• /
• pp.354-360
• /
• 2019

In order to extend the shelf life of Wasabi paste, the effects of citric acid were confirmed at $35^{\circ}C$ for 28 days. Citric acid-treated groups contained citric acid in amounts of 0.05, 0.10, 0.17, 0.30, and 0.40%, respectively. Quality characteristics of Wasabi pastes were determined in pH, titratable acidity, soluble solid content, color values, microbial analysis (aerobic bacteria, yeast), gas production, and content of allyl isothiocyanate. The pH and titratable acidities of Wasabi pastes added with citric acid were indicated as 4.03-5.19 and 4.23-4.82%, respectively. Soluble solid content was significantly different according to concentrations of citric acid. L values showed the highest at $50.05{\pm}0.46$. a and b values were increased during the storage period. Total aerobic bacteria and yeast counts of Wasabi pastes were decreased in a dose-dependent manner. Gas production from Wasabi pastes showed at 19.55-19.80 mL/tube after 28 days of storage. The addition of citric acid (0.3% or more) to the Wasabi paste resulted in increased storage stability.

• Korean Journal of Poultry Science
• /
• v.46 no.3
• /
• pp.137-154
• /
• 2019

This study was conducted to develop and compare Samgyetang broth from extract of pre-treated chicken feet. Chicken feet were subjected to non-heating (control), heating at $70^{\circ}C$ for 12 h in a hot air dryer, and heating at $180^{\circ}C$ for 1 h in an oven. The heat-treated chicken feet were extracted at $121^{\circ}C$ for 1 h and 2 h, respectively. The extract was placed in a pouch with whole chicken carcass ($470{\pm}10g$). The sealed Samgyetang retort was made according to the industrial method. The pH of the extract from preheated chicken feet was lower than that extracted from fresh chicken feet. The Thiobarbituric Acid Reactive Substances (TBARS) value of the preheated chicken feet extract was significantly lower (P<0.05) than that of fresh chicken feet extract, but there were no significant differences among the broths. As the extraction time increased, the pH and TBARS value decreased in the extract (P<0.05) but increased in the broth (P<0.05). According to the sensory evaluation test, the extract from 1 h hot air heating and drying was significantly better in appearance, aroma, and overall preference than the other treatments (P<0.05). The GC-MS results showed that benzaldehyde and benzothiazole, which are widely known to give meat and nuts flavor, were detected in those treatments (P<0.05). The Samgyetang broths prepared from 1 h hot air heating and drying extract were significantly higher in the overall acceptability according to the sensory test (P<0.05). In summary, the quality of retort Samgyetang broth can be improved by adding chicken feet extract which is subjected to heating and drying for 1 h.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.3
• /
• pp.1018-1027
• /
• 2019

Natural-derived protein-derived low molecular weight peptides have been known to have physiological activities such as antioxidant, hypertension relief, immunomodulation, pain relief and antimicrobial activity. In this study, the low-molecular peptides were produced using commercial proteases (alcalase, bromelain, flavourzyme, neutrase, papain, protamex), and the antioxidant activity (DPPH scavenging activity, superoxide radical scavenging activity, hydroxy radical scavenging activity, and metals chelation capacity), constituent amino acid and molecular weight of the peptide were analyzed. Enzyme reaction was performed by adding 50 g of chopped Ogae meat slurry and 2%(w/v) protein enzyme into the enzyme reactor for 2 h at a pH of 6 and a temperature of $60^{\circ}C$. The degree of hydrolysis(%) after the reaction ranged from $36.65{\pm}4.10%$ to $70.75{\pm}5.29%$. The highest degree of hydrolysis of protamex was 46.3%, and the highest value of papain hydrolysate was $70.75{\pm}5.29%$. On the other hand, alcalase hydrolysate showed the lowest value of $36.65{\pm}4.10%$. Bromelain-treated low molecular weight peptides showed the highest DPPH radical scavenging activity and the lowest scavenging activity of alcalase-treated peptides. Superoxide radical scavenging activity showed that bromelain treated low molecular peptide showed the highest radical scavenging activity of 50% or more. Hydroxyl radical scavenging activity ranged from about 16.73 to 69.16%, the highest among bromelain-treated low molecular peptides. $Fe^{2+}$ chelation abilities showed a distribution between about 17.85 to 47.84%. The chelation capacity of the hydrolysates was not significantly different without any difference to the enzymes used. The results of amino acid analysis showed differences between hydrolysates of alcalase, bromelain, flavourzyme, neutrase, papain, and protamex enzymes. The most amino acid was glutamic acid. The molecular weight distribution of the enzyme hydrolyzates was in the range of 300-2,000 Da, although the molecular weight distribution differed according to the treated enzymes.