• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.1
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• pp.66-72
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• 2017

Potato greening determines the shelf life and affects the marketability of this tuber. Various stresses during handling and storage interact to affect the tuber's physiological status and can affect the rate of greening. This study investigated the effects of storage temperature on tuber greening and shelf life in unwashed and washed potatoes of the cultivar Superior. Physiological and biochemical changes were examined during 15 days at room temperature ($23{\pm}2^{\circ}C$) under cool-white fluorescent light after storage for 1 month at different temperatures ($4^{\circ}C$, $20^{\circ}C$). Hunter a values were negative (-) for washed potatoes after 3 days (-0.8) and 15 days (-2.5) at room temperature following 1 month of storage at $4^{\circ}C$ while positive (+) values were observed for unwashed potatoes after 15 days at room temperature. The Hunter ${\Delta}E$ values of washed potatoes previously stored at $4^{\circ}C$ for 1 month increased after 3 days at room temperature compared with those of unwashed potatoes. The total chlorophyll content of washed potatoes was higher than that of unwashed potatoes. The highest correlation was observed between the Hunter ${\Delta}E$ value and Hunter a value (-0.93506), while a positive correlation coefficient (0.89806) was observed between greening criteria and Hunter ${\Delta}E$ value by using colorimetry. We conclude, therefore, that there is a biosynthetic link between temperature-induced chlorophyll accumulation and tuber greening in storage.

• Journal of Dairy Science and Biotechnology
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• v.32 no.1
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• pp.17-29
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• 2014

GRAS probiotics can be used to modulate intestinal microbiota and to alleviate various gastrointestinal disorders. In several recent studies, researchers have explored the potential expansion and usability of probiotics to reduce the risk factors associated with diseases, including obesity, hypercholesterolemia, arterial hypertension, hyperhomocysteinemia, and oxidative stress. In this review, our aim was to clarify the mechanism underlying interactions between hosts (animal or human) and probiotics and the beneficial effects of probiotics on human health.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.297-305
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• 2006

The field lysimeter experiment were undertaken to investigate the runoff and erosion loss of four pesticides from sloped land by rainfall and to assess the influence of pesticide properties, environmental factors and agricultural practices on them. The pesticide losses from soybean planted field and bare field were measured using field lysimeters. Pesticide losses from a series of lysimeter plots of sloped land by rainfall ranged $0.1{\sim}0.6%$ for alachlor, $1.1{\sim}4.5%$ for ethalfluralin, $8{\sim}31%$ for pendimethalin and 0.03% for ethoprophos, which were $1/3{\sim}2.5$ times to them in the simulated rainfall study. The erosion loss rates of pesticides from soybean-plots were $21{\sim}75%$ lower than the ones from bare soil plot. The effect of slope conditions was not great for runoff loss, but for erosion loss increased to maximum $4{\sim}12$ times by sloping degree and slope length. The peak runoff concentration in soybean-plots and bale soil plots were $3{\sim}278{\mu}gL^{-1}\;and\;6{\sim}450{\mu}gL^{-1}$ for alachlor, $1.1{\sim}11.4{\mu}gL^{-1}\;and\;0.9{\sim}16{\mu}gL^{-1}$ for ethalfluralin, $7{\sim}42{\mu}gL^{-1}\;and\;6{\sim}66{\mu}gL^{-1}$ for pendimethalin, and $2{\sim}53{\mu}gL^{-1}\;and\;0.1{\sim}113{\mu}gL^{-1}$ for ethoprophos, respectively, on nine different slope degree and slope length plots. Therefore, the differences of the peak runoff concentration between bare soil plots and soybean-plots were not great.

• Science of Emotion and Sensibility
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• v.14 no.4
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• pp.571-580
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• 2011

The purpose of this study was to evaluate the effects of secondary task such as sending text message (STM) and searching navigation (SN) using the variable indicating control of vehicle ((Medial-Lateral Coefficient of Variation, MLCV), (Anterior-Posterior Coefficient of Variation, APCV)) and motion signal (Jerk-Cost function, JC). Participants included 50s taxi drivers; 14 males and 14 females. Participants were instructed to keep a certain distance (30m) from the car ahead with constant speed (80km/hr or 100km/hr). Experiement consisted of driving alone for 1minute and driving with secondary task for 1minute. Both MLCV and APCV were significantly increased during Driving + Sending Text Message(STM) and Driving + Searching Navigation(SN) than Driving only. Also, JC was increased during Driving + STM and Driving + SN than Driving only. In this study, we found that even in the experts group who are taxi driver and have 25 years driving experience, the smoothness of motion is decreased and the control of vehicle is disturbed when they were performing secondary tasks like sending text message or searching navigation.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.273-278
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• 2007

Recently, the demand for the powdered products to process raw grains and vegetables has been expanded, and the growth possibility of their fields(markets) in the future will be highly valued with the westernization of living environment and the change of the dietary life. We have bought and analyzed the 111 products of raw grains and vegetables from the large-sized marts, markets and internet orders from March to October 2006. The rate of moisture content was $1.7{\sim}12.5%$. We also found out that the foods over 10% moisture content was 8 of those samples we bought or collected. Their ash rates were averagely $0.3{\sim}8.6%$. The number of those foods that the alien substances were detected was 2. The tar pigments, artificial sweeteners and sulfur dioxides of components that contained food additives were not detected. Each detection range of Cadmium, Lead and Arsenic of the injurious heavy metals was non-detectable $(nd){\sim}0.55,\;nd{\sim}4.52,\;nd{\sim}0.10mg/kg$, while the average detection content were 0.08, 0.48, 0.01 mg/kg. By investigating the contamination degree of the microflora, we discovered that the number of the aerobic plate count, B. cereus over 1,000 cfu/g and C. perfringens over 100 cfu/g was 36 (32.4%), 9 (8.1%) and zero, and that the whole sanitation condition of the products of powdered raw grains and vegetables circulated in the market was not so good.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.755-762
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• 2000

Physicochemical properties of commercial sweet potato starches manufactured by 7 different companies were investigated in comparison with corn and potato starches. Crude ash and protein content varied from 0.36 to 1.02%, and from 0.04 to 0.14% based on dry weight, respectively. The protein contents were relatively smaller than that of corn or potato starch. But whiteness of the sweet potato starches was less than that of corn or potato starch. Mean diameter of the sweet potato starch granules varied from 14.23 to $21.08\;{\mu}m$ depending on the company and all sweet potato starches showed bimodal size distributions. Pasting viscosity measured by Rapid Viscoanalyzer(RVA) also showed variations among the starches of different companies. The starch from D company in Korea had the lowest pasting temperature$(74.00^{\circ}C)$ whereas the starch from a phillippine company(P) did the highest one$(80.35^{\circ}C)$. The peak viscosity of sweet potato starches was higher than that of corn starch but lower than that of potato starch. The D company starch also showed the highest peak viscosity(2283 cp) among the starches tested. Paste breakdown by hot shearing ranged from 524 cp (S company) to 1279 cp (HL company). Textural properties of the starch gels appeared significantly different among the starches of different manufacturers. The greatest hardness of the gel was $137.90\;g_{f}$ at 1 day storage whereas the lowest value was $31.53\;g_{f}$. Except the starches from 2 companies (P and S), the sweet potato starches formed very soft and weak gels. P or S company starches formed the gels similar to potato starch. Syneresis by freeze-thawing treatments appeared less for sweet potato starch gels than that for corn starch gels, but greater than that for potato starch gel. The overall properties of the sweet potato starches varied by the manufacturing companies, and ranged between those of corn and potato starches.

• The Journal of Pediatrics of Korean Medicine
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• v.24 no.2
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• pp.40-48
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• 2010

Objectives The purpose of this study is to get the basic information about the actual amount of consumption of the Health supplements and Herbal Medicines. Also, we investigated the consumption differences according to the regions. Methods 500 questionnaires were handed out to parents of elementary students in O O, Gyeonggi-do province, and 331 questionnaires were collected and evaluated for this study. Results Among the 331 students, 58.4% were female, and 41.6% were male. The percentages of the subjects consuming health supplements and herbal medicines were 67.4% and 59.2% respectively. The maximum period of taking the health supplements were from 1 month to 6 month (49.5%), and the maximum period of taking the herbal medicine was within one month (55.6%). The total cost of the health supplements was less than 100,000won (43.7%), which was the most common while herbal medicine cost was between 100,000won and 200,000won (40.6%). The most common age of consuming the health supplements and herbal medicine for the first time was six to ten years old (47.3%); the case of herbal medicine was one to six years old (64.0%). Most of people purchased health supplements from pharmacy (48.0%), and purchased the herbal medicine from the oriental medical clinic (61.8%). Among those people who purchased health supplements, they bought nutritional supplements (82.8%), red ginseng or ginseng products (43.4%), plum extract products (10.9%), and chlorella products (6.8%). The reason for consuming health supplements was to be healthier even though there is no ongoing illness (47.1%), which was the most common reason. The reason for consuming herbal medicine was to cure weakness (39.3%). For the responses about effectiveness after taking medications, people thought herbal medicine seemed to be more effective compare to health supplements (72.3%, 63% respectively). Only 1.4% of the subjects consuming the health supplements showed adverse effects while herbal medicine showed 4.6%. The most common adverse effects were 'general reaction' caused by the health supplements and dermatologic problems caused by the herbal medications. Conclusions Among 331 subjects, the percentage of consuming the health supplements (67.4%) was higher than the Herbal Medicine (59.2%). The total consuming cost of the herbal medications was higher than general health supplements. Also, the maximum period of consuming the health supplements was longer than herbal medications. Therefore, it is shown that herbal medications have no price competitiveness compare to health supplements. The age of using the herbal medicine for the first time was younger than the health supplements. Even though many people can purchase both health supplements and herbal medication from pharmacies and local oriental medical clinic, it is also shown that some people thought that the health supplements should be purchased from oriental medical hospital (13.9%). The most commonly taken forms of the health supplement was nutrition-supplying products, and the second common health supplements were ginseng and red ginseng. The health supplements were commonly consumed for preventing illness and for maintaining healthy life rather than for cure diseases. On the other hand, the herbal medicine was more commonly consumed to be taller or to treat diseases. More than half of the entire people replied as 'satisfied' for their purchase. Some adverse effects and general reaction were common with the subjects consuming health supplements while dermatological adverse reaction was common with the subjects consuming herbal medications.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.9
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• pp.662-669
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• 2011

This study was conducted to biologically convert methane into methanol. Methane contained in biogas was bio-catalytically oxidized by methane monooxygenase (MMO) of methanotrophs, while methanol conversion was observed by inhibiting methanol dehydrogenase (MDH) using MDH activity inhibitors such as phosphate, NaCl, $NH_4Cl$, and EDTA. The degree of methane oxidation by methanotrophs was the most highly accomplished as 0.56 mmol for the condition at $35^{\circ}C$ and pH 7 under 0.4 (v/v%) of biogas ($CH_4$ 50%, $CO_2$ 50%) / Air ratio. By the inhibition of 40 mM of phosphate, 50 mM of NaCl, 40 mM of $NH_4Cl$ and $150{\mu}m$ of EDTA, methane oxidation rate could achieve more than 80% regardless of type of inhibitors. In the meantime, addition of 40 mM of phosphate, 100 mM of NaCl, 40 mM of $NH_4Cl$ and $50{\mu}m$ of EDTA each led to generating the highest amount of methanol, i.e, 0.71, 0.60, 0.66, and 0.66 mmol when 1.3, 0.67, 0.74, and 1.3 mmol of methane was each concurrently consumed. At that time, methanol conversion rate was 54.7, 89.9, 89.6, and 47.8% respectively, and maximum methanol production rate was $7.4{\mu}mol/mg{\cdot}h$. From this, it was decided that the methanol production could be maximized as 89.9% when MDH activity was specifically inhibited into the typical level of 35% for the inhibitor of concern.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.11
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• pp.603-610
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• 2016

This work studies the synthesis of birnessite (${\delta}-MnO_2$), a catalyst of oxidative-coupling reactions, from the powder of spent alkaline manganese batteries (SABP, <8 mesh) and evaluate its reactivity for 1-naphthol (1-NP) removals. Manganese oxides using commercial reagents ($MnSO_4$, $MnCl_2$) and the acid birnessite (A-Bir) by McKenzie method were also synthesized, and their crystallinity and reactivity for 1-NP were compared with one another. 96% Mn and 98% Zn were extracted from SABP by acid leaching at the condition of solid/liquid (S/L) ratio 1:10 in $1.0M\;H_2SO_4+10.5%\;H_2O_2$ at $60^{\circ}C$. From the acid leaching solution, 69% (at pH 8) and 94.3% (pH>13) of Mn were separated by hydroxide precipitation. Optimal OH/Mn mixing ratio (mol/mol) for the manganese oxide (MO) synthesis by alkaline (NaOH) hydrothermal techniques was 6.0. Under this condition, the best 1-NP removal efficiency was observed and XRD analysis confirmed that the MOs are corresponding to birnessite. Kinetic constants (k, at pH 6) for the 1-NP removals of the birnessites obtained from Mn recovered at pH 8 (${Mn^{2+}}_{(aq)}$) and pH>13 ($Mn(OH)_{2(s)}$) are 0.112 and $0.106min^{-1}$, respectively, which are similar to that from $MnSO_4$ reagent ($0.117min^{-1}$). The results indicated that the birnessite prepared from the SABP as a raw material could be used as an oxidative-coupling catalyst for removals of trace phenolic compounds in soil and water, and propose the recycle scheme of SAB for the birnessite synthesis.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.2
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• pp.89-100
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• 1999

The rain water samples were collected at Chunchon and Seoul by using wet only automatic sampler from January 1996 through 1997. The daily base rain water samples collected over than 95% rainy events components, $SO_4^{-2}$, $NO_3^-$, $CI^-$, NH_4^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$, and $K^+$, by ion chromatography. In 1996, about 77% of sampled rain water showed below pH 5.6 and the 60% of rain water was lower than pH 5.0. The volume weighted average pH was 4.7 at all sites. In 1997, the volume weighted average pH was 4.6 and 4.9 at Seoul and Chunchon, respectively. Among the rain water samples,, 87% and 55% fo samples showed below than pH 5.6 and 5.0, respectively. The pH value of Chunchon was significantly (p＜0.05) lower than Seoul at the rain samples for less than 20mm rainfall. However conductivity of the rain samples were 20.9$\mu$S/cm for 1996 and 27.7$\mu$S/cm for 1997 at Seoul, and 19.1$\mu$S/cm for 1996 and 14.1$\mu$S/cm for 1997 at Chunchon. $H_2SO_4$ and $HNO_3$ contributed 65.9% and 29.6% of free acidity at Seoul, respectively. The ratio of [$NO_3^-$]/[nss-$SO_4^{-2}$] were 0.43 at Seoul and 0.51 at Chunchon for rain samples for less than 20mm rainfall. The annual wet deposition of $CI^-$, $NO_3^-$, $SO_4^{-2}$, $H^+$M, $Na^+$, NH_4^+$, $K^+$, $Mg^{2+}$, and $Ca^{2+}$, respectively, 568.8kg/$ extrm{km}^2$, 1489.3kg/$\textrm{km}^2$, 3184.8kg/$\textrm{km}^2$, 20.9kg/$\textrm{km}^2$, 249.4kg/$\textrm{km}^2$, 1091.2kg/$\textrm{km}^2$, 189.8kg/ $\textrm{km}^2$, 90.2kg/$\textrm{km}^2$ and 702.4kg/$\textrm{km}^2$ at Seoul for 1996; 656.4kg/$\textrm{km}^2$, 2029.7kg/$\textrm{km}^2$, 3280.7kg/$\textrm{km}^2$, 27.2kg /$\textrm{km}^2$, 229.4kg/$\textrm{km}^2$, 1063.9kg/$\textrm{km}^2$, 106.9kg/$\textrm{km}^2$, 78.2kg/$\textrm{km}^2$, 645.3kg/$\textrm{km}^2$ at Seoul for 1997; 116.9kg/ $\textrm{km}^2$, 983.3kg/$\textrm{km}^2$, 1797.0kg/$\textrm{km}^2$, 21.4kg/$\textrm{km}^2$, 83.2kg/$\textrm{km}^2$, 648.1kg/$\textrm{km}^2$, 78.0kg/$\textrm{km}^2$, 22.2kg/$\textrm{km}^2$, 368.8kg/$\textrm{km}^2$ at chunchon for 1996; 100.2kg/$\textrm{km}^2$, 1077.6kg/$\textrm{km}^2$, 1754.0kg/$\textrm{km}^2$, 13.4kg/$\textrm{km}^2$, 146.0kg/$\textrm{km}^2$, 602.3kg/$\textrm{km}^2$, 88.8kg/$\textrm{km}^2$, 16.2kg/$\textrm{km}^2$ and 206.8kg/$\textrm{km}^2$ at chunchon for 1997.