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토마토 양액재배시 배지 환경조성이 생육 및 생산성에 미치는 영향 (Effects of Environmental Substrate Composition on the Growth and Yield of Hydroponically Grown Tomato)

  • 이재수;이현동;이상규;곽강수;김밝금;김태현;백정현;노시영;홍영신
    • 한국환경과학회지
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    • 제28권9호
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    • pp.729-735
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    • 2019
  • The aim of this study was to determine the effects of different compositions of environmental substrates on hydroponic tomato cultivation. Three different substrates were used in coir chip:dust (v/v=50:50; CP1), coir chip:dust (v/v=80:20; CP2), and rock wool cube with CP2 (CPR). The amount of irrigation during the cultivation period was 190 mL/(plant time) in all substrates. The pH and EC were 5.8-6.2 and 2.6-2.9 dS/m, respectively. The drainage rate in CP1 was 31%, in CP2 was 36%, and in CPR was 29%. The growth of tomato plants in terms of height was higher in CP1 and CPR. The leaf area was greater in CP2. The fresh and dry weights were greater in CP2 and CPR treatments. The net photosynthesis in CP2 ($19.31{\mu}mol\;CO_2/m^2s$) and root activity in CP2 were higher among all three treatments. The soluble solid content of fruit was not significantly different among treatments. The yield per plant in CP2 and CPR treatments was 17% greater than the yield per plant in CP1. Therefore, the most suitable substrate for hydroponic tomato cultivation is the substrate mixed with coir chip:dust (v:v=80:20; CP2), i.e., CPR.

침강지 시설이 조성된 LID 시설의 환경적 영향평가 (Comparative assessment of urban stormwater low impact strategies equipped with pre-treatment zones)

  • ;;전민수;김이형
    • 한국습지학회지
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    • 제21권2호
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    • pp.181-190
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    • 2019
  • 최근 강우유출수를 비용효율적으로 관리하기 위해 저영향개발 (Low Impact Development, LID)과 자연기반해법(Nature-based solution, NBS)를 도입하고 있다. 본 연구에서는 LID 시설 중 도심지 내 적용가능하고 유입부에 침강지가 조성된 침투도랑(IT)과 소규모 인공습지(SCW) 등 2개의 시설에 대해 효율성을 평가하였다. 효율성 평가는 장기간의 모니터링을 통한 자료를 이용하여 수행하였다. 분석결과 하절기 기간은 식생의 흡입 등의 생물학적 활동으로 인하여 SCW의 효율이 더 높았으나, 동절기 기간에는 식물의 고사로 인하여 IT의 효율이 더 높은것으로 분석되었다. 침강지 내 퇴적물의 분석결과 SCW 침강지 내 식생에 의한 정화작용 및 미생물등의 생물학적 처리기작으로 인하여 COD와 TN의 저감효율이 높은것으로 분석되었다. 본 연구에서는 침강지 시설을 조성한 LID 시설에 대해 비교하였으며, 자연과 유사한 자연기반해법을 LID 시설에 적용할 경우 기존 시설보다 처리효율이 우수한것으로 나타났다.

Mathematical Models to Describe the Kinetic Behavior of Staphylococcus aureus in Jerky

  • Ha, Jimyeong;Lee, Jeeyeon;Lee, Soomin;Kim, Sejeong;Choi, Yukyung;Oh, Hyemin;Kim, Yujin;Lee, Yewon;Seo, Yeongeun;Yoon, Yohan
    • 한국축산식품학회지
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    • 제39권3호
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    • pp.371-378
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    • 2019
  • The objective of this study was to develop mathematical models for describing the kinetic behavior of Staphylococcus aureus (S. aureus) in seasoned beef jerky. Seasoned beef jerky was cut into 10-g pieces. Next, 0.1 mL of S. aureus ATCC13565 was inoculated into the samples to obtain 3 Log CFU/g, and the samples were stored aerobically at $10^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$ for 600 h. S. aureus cell counts were enumerated on Baird Parker agar during storage. To develop a primary model, the Weibull model was fitted to the cell count data to calculate Delta (required time for the first decimal reduction) and ${\rho}$ (shape of curves). For secondary modeling, a polynomial model was fitted to the Delta values as a function of storage temperature. To evaluate the accuracy of the model prediction, the root mean square error (RMSE) was calculated by comparing the predicted data with the observed data. The surviving S. aureus cell counts were decreased at all storage temperatures. The Delta values were longer at $10^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$ than at $30^{\circ}C$ and $35^{\circ}C$. The secondary model well-described the temperature effect on Delta with an $R^2$ value of 0.920. In validation analysis, RMSE values of 0.325 suggested that the model performance was appropriate. S. aureus in beef jerky survives for a long period at low storage temperatures and that the model developed in this study is useful for describing the kinetic behavior of S. aureus in seasoned beef jerky.

Effects of dietary humic acid and enzymes on meat quality and fatty acid profiles of broiler chickens fed canola-based diets

  • Disetlhe, Amogelang R.P.;Marume, Upenyu;Mlambo, Victor;Hugo, Arno
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권5호
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    • pp.711-720
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    • 2019
  • Objective: This study was conducted to assess the effect of potassium humate and enzymes (Xylanase+Amylase+Protease) inclusion in diets on carcass characteristics, meat quality and fatty acid profiles of broilers fed canola-based diets. Methods: Two hundred and twenty broilers randomly allotted to 5 dietary treatments: the control (commercial broiler diet); CM (17.5% canola meal inclusion); CMEnz (17.5% CM inclusion+0.3 g/kg Axtra XAP); CMPh (17.5% CM inclusion+1.5% Potassium Humate, PH); and CMEnzPh (17.5% CM inclusion+1.5% PH+0.3 g/kg Axtra XAP) were slaughtered at day 42 for assessment of carcass and meat quality parameters. Results: Diet had no effect on carcass traits apart from breast muscle weight and breast muscle index. The highest breast muscle weight was observed in broilers fed CMEnz ($487.6{\pm}17.5g$) followed by those fed the control diet ($474.37{\pm}17.5g$). Diet also had no significant dietary effect on pH, temperature, drip loss and shear force values of the breast muscle. However, diet significantly affected meat colour and water-holding capacity. Broilers in the control and CMPh groups ($52.94{\pm}0.67$ and $52.91{\pm}0.67$) had the highest (p<0.05) values for lightness ($L^*$), whilst those fed CMEnzPh had the lowest value ($47.94{\pm}0.67$). In contrast, CM group had the lowest (p<0.05) value for redness ($a^*$) with CMEnzPh group having the highest values. The proportion of polyunsaturated fatty acids (PUFAs), n-6 and n-3 fatty acids and the PUFA/saturated fatty acid ratio were increased in CM-based diets containing enzymes and humic acid. Conclusion: It can, therefore, be concluded that CM can be included in broiler diets in the presence of enzymes and humic acid with positive effects on meat quality and important fatty acids that are beneficial to the health of consumers.

Zearalenone exposure affects the Wnt/β-catenin signaling pathway and related genes of porcine endometrial epithelial cells in vitro

  • Song, Tingting;Yang, Weiren;Huang, Libo;Yang, Zaibin;Jiang, Shuzhen
    • Animal Bioscience
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    • 제34권6호
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    • pp.993-1005
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    • 2021
  • Objective: Zearalenone (ZEA) has estrogen-like effects. Our previous study has shown that ZEA (0.5 to 1.5 mg/kg) could induce abnormal uterine proliferation through transforming growth factor signaling pathway. To further study the other regulatory networks of uterine hypertrophy caused by ZEA, the potential mechanism of ZEA on porcine endometrial epithelial cells (PECs) was explored by the Illumina Hiseq 2000 sequencing system. Methods: The PECs were treated with ZEA at 0 (ZEA0), 5 (ZEA5), 20 (ZEA20), and 80 (ZEA80) µmol/L for 24 h. The collected cells were subjected to cell cycle, RNA-seq, real-time quantitative polymerase chain reaction, immunofluorescence, and western blot analysis. Results: The proportion of cells in the S and G2 phases decreased (p<0.05), but the proportion of cells in the G1 phase increased (p<0.05) in the ZEA80 treatment. Data analysis revealed that the expression of Wnt pathway-related genes, estrogen-related genes, and mitogen-activated protein kinase pathway-related genes increased (p<0.05), but the expression of genetic stability genes decreased (p<0.05) with increasing ZEA concentrations. The relative mRNA and protein expression of WNT1, β-catenin, glycogen synthase kinase 3β (GSK-3β) were increased (p<0.05) with ZEA increasing, while the relative mRNA and protein expression of cyclin D1 (CCND1) was decreased (p<0.05). Moreover, our immunofluorescence results indicate that β-catenin accumulated around the nucleus from the cell membrane and cytoplasm with increasing ZEA concentrations. Conclusion: In summary, ZEA can activate the Wnt/β-catenin signaling pathway by up-regulating WNT1 and β-catenin expression, to promote the proliferation and development of PECs. At the same time, the up-regulation of GSK-3β and down-regulation of CCND1, as well as the mRNA expression of other pathway related genes indicated that other potential effects of ZEA on the uterine development need further study.

대강활탕(大羌活湯)이 흰쥐에서 MIA로 유발된 골관절염에 미치는 항염증 및 연골 보호 효과 (Anti-inflammatory and Cartilage Protection Effects of Daeganghwal-tang in MIA-induced Osteoarthritis at Rats)

  • 김주란;이정희;이윤규;이현종;김재수
    • 대한한의학방제학회지
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    • 제29권3호
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    • pp.127-145
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    • 2021
  • Objectives : The purpose of this study was to evaluate the effects of Daeganghwal-tang on knee cartilage in monosodium iodoacetate(MIA)-induced osteoarthritis rats. Methods : Forty SD rats were randomly divided into five groups(n=8/group): normal group was SD rats group injected with normal saline at left knee joint and administrated orally distilled water, control group was MIA-induced osteoarthritis SD rats group administrated orally distilled water, Indomethacin group was MIA-induced osteoarthritis SD rats group administrated orally indomethacin 2 mg/kg, DGHT(L) group was MIA-induced osteoarthritis SD rats group administrated orally 1280 mg/kg of Daeganghwal-tang, and DGHT(H) group was MIA-induced osteoarthritis SD rats group administrated orally 2560 mg/kg of Daeganghwal-tang. After orally administration of drugs for 4 weeks, gross appearance and histological analysis were used to evaluate the degree of knee cartilage damage. In addition, pro-inflammatory cytokines, bone degrade factor and bone defence factors were analyzed to investigate the anti-inflammatory and cartilage protection effects of Daeganghwal-tang. Also, hematological test, biochemical test, and liver and kidney tissue were analyzed to determine the safety of Daeganghwal-tang. Results : Daeganghwal-tang inhibited the damage of the knee cartilage, and significantly prevented the reduction in cartilage thickness. In addition, the pro-inflammatory cytokines and the bone degrade factor significantly decreased, and the bone defence factors significantly increased. In the safety assessment of Daeganghwal-tang, there were no significant differences among the experimental groups and no abnormal findings were observed. Conclusions : Daeganghwal-tang has anti-inflammatory effect, inhibits cartilage damage, and protects cartilage in MIA-induced osteoarthritis rats.

인도의 가정 및 산업 폐수 처리를 위한 인공습지: 총론 (Constructed Wetlands in Treating Domestic and Industrial Wastewater in India: A Review)

  • 케이 에스 파르헨;나쉬 제트 레예스;김이형
    • 한국습지학회지
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    • 제23권3호
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    • pp.242-251
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    • 2021
  • 인디아와 같은 개발 도상국에서는 규제없는 폐수 방류가 지표수 수질에 심각한 영향을 주고 있다. 인공습지(CW)는 생태학적 기작에 의하여 폐수 처리를 함으로써 수질정화와 함께 다양한 효과를 제공하는 효율적인 기술이다. 본 연구는 인디아의 폐수처리를 위해 조성된 다양한 형태의 인공습지에 대하여 자료를 정리하고 분석함으로써 객관적 효과 평가를 수행하고자 수행되었다. 연구에 사용된 인공습지 데이터는 기출판된 문헌에서 수집되었으며, 산업폐수의 경우 화학적 산소요구량(COD), 생화학적 산소요구량(BOD)이 높게 나타났다. 인디아의 생활하수 총질소(TN)와 총인(TP)은 산업폐수보다 낮은 농도를 보였다. 수직흐름 인공습지(VFCW)와 수평흐름 인공습지(HFCW)는 생활하수 및 산업 폐수의 TSS, BOD, TP 제거에 효과적으로 나타났다. 그러나 COD는 하이브리드 인공습지(HCW)에서 높은 제거율을 보였다. 인도에서는 인공습지를 폐수처리 시설의 고도처리로 활용될 경우 수질이 크게 향상되는 것으로 나타났다. 인공습지의 방류수 수질은 관개용수 및 기타 농업용수로 활용가능한 수질로 평가되었다. 본 연구결과는 인디아의 지역적 특성에 적정한 인공습지 설계에 기여할 것으로 평가된다.

매스티지 브랜드 광고모델 국적의 조절효과에 대한 연구: 해석수준이론을 중심으로 (A Study on the Moderating Effect of Nationality of Advertising Models for Masstige Brands: Based on Construal Level Theory)

  • 진진곤;방정혜;김민선
    • 한국산학기술학회논문지
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    • 제22권2호
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    • pp.362-367
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    • 2021
  • 본 연구는 방한 중국관광객에 대해 브랜드 인지도와 지각된 가격공정성이 매스티지 구매의도에 미치는 영향을 확인하고, 한·중 양국의 유명 광고모델이 이 관계에 어떻게 영향을 미치는 지 연구하였다. 명품의 이미지와 합리적인 가격대라는 매스티지의 특성에 따라 매스티지 원산지와 일치하는 국적(한국)모델과 중국관광객의 자국(중국)모델의 영향을 해석수준이론을 통하여 살펴보고자 하였다. 가설검증을 위해 2(브랜드인지도 고·저)×2(가격공정성)×2(광고모델 국적) 집단 간 실험설계를 실시하였다. 연구결과, 브랜드 인지도와 지각된 가격공정성은 각각 매스티지 구매의도에 정의 영향을 미쳤으며, 광고모델 국적의 조절효과도 유의미하였다. 광고모델이 한국 국적일 경우 브랜드인지도와 지각된 가격 공정성의 구매의도에 대한 영향이 중국 국적의 광고모델의 경우보다 더 크게 나타났다. 본 논문은 매스티지 브랜드는 중국 관광객에게 심리적 거리감이 있더라도 브랜드이미지에 맞는 한류 모델의 영향이 중국 모델보다 더 크다는 것을 보여준 연구로서 시사점이 있다고 하겠다.

경기, 강원 지역 농업용수의 미생물학적 특성 및 농업용수 분리 대장균의 항생제 내성 (Microbiological Quality and Antibiotic Susceptibility of E. coli Isolated from Agricultural Water in Gyeonggi and Gangwon Provinces)

  • 황인준;박대수;채효빈;김은선;윤재현;나겐드란 라자린감;최송이;김세리
    • 한국환경농학회지
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    • 제39권4호
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    • pp.343-351
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    • 2020
  • BACKGROUND: Irrigation water is known to be one of the major sources of bacterial contamination in agricultural products. In addition, anti-microbial resistance (AMR) bacteria in food products possess serious threat to humans. This study was aimed at investigating the prevalence of foodborne bacteria in irrigation water and evaluating their anti-microbial susceptibility. METHODS AND RESULTS: Surface water (n = 66 sites) and groundwater (n = 40 sites) samples were collected from the Gyeongi and Gangwon provinces of South Korea during April, July, and October 2019. To evaluate the safety of water, fecal indicators (Escherichia coli) and foodborne pathogens (E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were examined. E. coli isolates from water were further tested for antimicrobial susceptibility using VITEK2 system. Overall, detection rate of foodborne pathogens in July was highest among three months. The prevalence of pathogenic E. coli (24%), Salmonella (3%), and L. monocytogenes (3%) was higher in surface water, while only one ground water site was contained with pathogenic E. coli (2.5%). Of the 343 E. coli isolates, 22.7% isolates were resistant to one or more antimicrobials (ampicillin (18.7%), trimethoprim-sulfamethoxazole (7.0%), and ciprofloxacin (6.7%)). CONCLUSION: To enhance the safety of agricultural products, it is necessary to frequently monitor the microbial quality of water.

옥수수 밭에서 유기질 비료가 토양 비옥도 및 토양 호흡에 미치는 영향 (Impacts of Different Organic Fertilizers on Soil Fertility and Soil Respiration for a Corn (Zea mays L.) Cropping System)

  • 브렘퐁 바두 마비스;황현영;이상민;이초롱;안난희
    • 유기물자원화
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    • 제30권4호
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    • pp.151-163
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    • 2022
  • 본 연구는 친환경 농산물 생산을 위한 양분관리 자재로 유기질비료 처리에 따른 옥수수 재배 토양의 비옥도 및 토양 호흡에 미치는 영향을 분석하였다. 시험장소는 국립농업과학원 유기농업과 시험포장에서 수행하였으며 처리구는 퇴비 (Com), 발효비료 (FOF), 혼합 유박 (PC), 무비구 (NF)로 처리구당 3반복 완전임의 배치하였다. 처리량은 174kg N/ha로 옥수수 표준시비량의 질소기준에 준하여 처리하였다. 옥수수 정식 8주 후 토양분석 결과, 퇴비는 토양의 탄소 (C)와 질소 (N)를 각각 7.48 및 0.76g/kg으로 증가시켰고, 다른 처리구는 시험 전과 차이가 없었다. 또한 시험 후 토양의 화학적 특성은 무비구를 제외하고 유의한 차이는 없었다. 토양 CO2 발생량은 발효비료 처리가 다른 처리구보다 31-76% 증가시켰으며 두 번의 제초작업 후 CH4 발생량의 차이는 없었다. 토양의 N2O 배출량은 발효비료 처리가 다른 처리구보다 87-96% 감소되었다. 미생물 밀도 조사 결과, 시험 전에 비해 시험 후 토양의 사상균 및 방선균 밀도를 각각 25%, 16% 증가되었다. 따라서 친환경 농산물 생산을 위한 발효비료 등 유기질 비료는 자원을 순환하며 토양 생산성을 유지하는데 기여할 것이다.