• Environmental Engineering Research
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• 제25권3호
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• pp.393-399
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• 2020

The use of different types of wastewater (WW) for the cultivation of microalgae and cyanobacteria during recent decades has provided important economic and environmental benefits. However, direct use of WW can lead to growth inhibition and biomass contamination. In the present study, we separated the key WW nutrients, namely nitrate and phosphate, by adsorption and regeneration and used the resulting regenerated water to cultivate the cyanobacterium Spirulina platensis. The adsorbent was granular γ-alumina derived from waste aluminum cans. This procedure recovered 19.9% of nitrate and 23.7% of phosphate from WW. The cyanobacterial cultures efficiently assimilated the nutrients from the medium prepared using regenerated WW, and the growth and nutrient uptake were similar to those in a synthetic medium. In addition, imposing nutrient limitations to increase carbohydrate productivity was easily achieved using regenerated wastewater nutrients, without requiring additional dilution or complex processing. In acute toxicity tests, the harvested biomass in a regenerated medium had similar toxicity levels compared to the biomass obtained from a synthetic medium. The proposed method of using regenerated WW to produce contamination-free biomass has broad potential applications.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.149-158
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• 2009

American sycamore seedlings were grown in chambers with two different ozone concentrations ($O_3$-free air and air with additional $O_3$) for 45 days. Both the control and the $O_3$ chambers included non-fertilized and fertilized plants. After 18 days of $O_3$ fumigation, seedlings were placed in a clean chamber for 27 days. Seedlings under ozone fumigation showed a significant decrease in pigment contents and photosynthetic activity, and a significant increase in lipid peroxidation. Fertilization enhanced physiological damage such as the inhibition of photosynthetic activity and the increase of lipid peroxidation under ozone fumigation. During the recovery phase, the physiological damage level of seedlings increased with ozone fumigation. In addition, physiological damage was observed in the fertilized seedlings. Superoxide dismutase (SOD) and glutathione reductase (GR) activities of $O_3$-treated seedlings increased up to 33.8% and 16.3% in the fertilized plants. The increase of SOD activity was higher in the fertilized plants than in the non-fertilized plants. Negative effects of ozone treatment were observed in the biomass of the leaves and the total dry weight of the fertilized sycamore seedlings. The $O_3$-treated seedlings decreased in stem, root and total dry weight, and the loss of biomass was statistically significant in the fertilized plants. In conclusion, physiological disturbance under normal nutrient conditions has an effect on growth response. In contrast, in conditions of energy shortage, although stress represents a physiological inhibition, it does not seem to affect the growth response.

• Asian-Australasian Journal of Animal Sciences
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• 제28권5호
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• pp.662-670
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• 2015

The objectives of this study were to investigate the effects of feeding barley naturally contaminated with Fusarium mycotoxins on growth performance, vulva swelling, and digestibility of dry matter, organic matter, and crude protein of gilts and the recovery of gilts fed normal diets immediately after the exposure to contaminated diets by measuring growth performance and vulva swelling. In Exp. 1, four diets were prepared to contain 0%, 15%, 30%, or 45% contaminated barley containing 25.7 mg/kg deoxynivalenol and $26.0{\mu}g/kg$ zearalenone. Sixteen gilts with an initial body weight (BW) of 33.3 kg (standard deviation = 3.0) were individually housed in a metabolism crate and assigned to 4 diets with 4 replicates in a randomized complete block design based on BW. During the 14-d feeding trial, individual BW and feed consumption were measured weekly and the vertical and horizontal lengths of vulva were measured every 3 d. From d 10, feces were collected by the maker-to-marker method for 4 d. Blood samples were collected on d 14. During the overall period, the average daily gain, average daily feed intake, and gain:feed of pigs linearly decreased (p<0.01) as the dietary concentration of contaminated barley increased. However, the digestibility of crude protein was linearly increased (p = 0.011) with the increasing amounts of contaminated barley. Increasing dietary Fusarium mycotoxin concentrations did not influence vulva size, blood characteristic as well as immunoglobulin level of pigs. In the Exp. 2, a corn-soybean meal-based diet was formulated as a recovery diet. Pigs were fed the recovery diet immediately after completion of the Exp. 1. During the 14-d of recovery period, the individual BW and feed consumption were measured weekly and the vertical and horizontal length of vulva were measured every 3 d from d 0. On d 7, the feed intake of pigs previously fed contaminated diets already reached that of pigs fed a diet with 0% contaminated barley and no significant difference in growth performance among treatments was observed during d 7 to 14 of the recovery period. In conclusion, increasing levels of mycotoxins in diets linearly decreased the growth performance of pigs, and these damages can be recovered in 7 d after the diet was replaced with a normal diet. The vulva size, blood characteristic, immune responses were not affected by increasing level of contaminated barley in the diets fed to pigs.

• Journal of Plant Biology
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• 제33권2호
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• pp.147-150
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• 1990

Different species with similar niches can coexist in the same community if disturbances prevent compeptitive exclusion of competitively inferior species. Disturbances which open up gaps are common in all kind of community. Even in virgin forests without any artificial disturbance, there exist a significant proportion of trees of early successional shade-in-tolerant species in addition to the dominant late successional shade-tolerant species. In forest ecosystems, most canopy tree species including shade-tolerant ones require one or more gaps in their life-time to reach the canopy. Because of these frequent disturbances, forests can be considered of dynamic mosaics of patches of different ages and with different species composition which are in certain stages of recovery from disturbances. Disturbances temporarily increase the availability of resources such as light, water and soil nutrient for other in dividuals through the death of one or more canopy trees.

• 한국식품영양과학회지
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• 제30권2호
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• pp.357-363
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• 2001

This study examined the experience of vitamin/mineral supplement among adults in Seoul. Using a self-completed questionnaire including demographic information and use of vitamin/mineral supplement, 618 participants completed the study. The majority of respondents were female (72.2%), 40~49 years old (42.2%), and over college graduates (53.4%). Among the 618 respondents surveyed, 56% had experience of supplement use. The reasons for vitamin/mineral supplement use were health maintenance (56%), fatigue recovery (18%), disease prevention (8%), disease treatment (8%), and nutrition (8%) in order. The main considering factors for selecting vitamin/mineral supplement were side effect, cleanliness and reliability of company. The information sources for vitamin/mineral supplement were physician/pharmacist (45%), TV & advertisement (29%), family and relatives (19%). The main purchasing place for their supplement reported by the most of the respondents (84%) was from pharmacy.

• Nutrition Research and Practice
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• 제15권sup1호
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• pp.1-21
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• 2021

The coronavirus disease 2019 (COVID-19) pandemic has put focus on the importance of a healthy immune system for recovery from infection and effective response to vaccination. Several nutrients have been under attention because their nutritional statuses showed associations with the incidence or severity of COVID-19 or because they affect several aspects of immune function. Nutritional status, immune function, and viral infection are closely interrelated. Undernutrition impairs immune function, which can lead to increased susceptibility to viral infection, while viral infection itself can result in changes in nutritional status. Here, we review the roles of vitamins A, C, D, and E, and zinc, iron, and selenium in immune function and viral infection and their relevance to COVID-19.

• 한국토양비료학회지
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• 제45권5호
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• pp.779-786
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• 2012

과수원에서 화학비료 대체 가능성을 검토하기 위하여 녹비 작물을 단독으로 재배하는 경우와 녹비 재배 시 SCB 액비를 혼용하는 경우 녹비 생산량 및 토양 물리화학성 변화, 배 잎의 무기성분 함량 및 광합성 특성을 비교 분석하였다. 화본과 녹비작물의 경우, 녹비 단독 처리에 비해 SCB 액비 혼용 처리의 경우 녹비 생산량이 유의하게 증가하였고, 두과 녹비에 있어서도 유의성은 인정되지 않았으나 액비 혼용처리 시 생체중 및 건물중이 높게 나타났다. 호밀 + 액비 처리구와 헤어리베치 + 액비 처리구에서는 각각의 경우 액비를 시용하지 않았을 때보다 용적밀도가 감소하여 과수의 뿌리 생장이 용이할 것으로 판단되었다. 녹비 단독 및 녹비 + 액비 처리와 화학비료 시용에 따른 배 잎의 무기 성분함량은 처리 간에 차이가 없었다. 순광합성량 또한 처리 평균 간 차이가 인정되지 않았으나, 녹비 + 액비 혼용 처리구에서 녹비 단독 처리에 비해 높은 경향을 보였으며, 헤어리베치 + 액비의 경우 화학비료와 거의 같은 수준의 동화율을 보여 배 과원 표토 및 양분 관리를 위한 녹비 재배 시 활용 가능성이 높은 것으로 판단되었다. 녹비 단독 및 SCB 액비 혼용처리에 따른 토양 화학성 변화는 화학비료 처리에 비하여 pH는 높았고 질산태 질소는 장마기 이후 비슷한 경향을 보였으며, 치환성 칼리는 낮았으나, 치환성 마그네슘은 높게 나타났고, 녹비 단독 처리구와 비교 결과 SCB 액비 혼용 처리에서 약간 높은 경향을 나타내었다. 이상의 결과를 종합했을 때 과원에서 녹비작물 재배 시 장기적인 화학비료 대체를 위해서는 SCB 액비를 함께 도입함으로써 부족한 양분을 보충하는 것이 필요할 것으로 판단되었다.

• 생물환경조절학회지
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• 제24권1호
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• pp.13-20
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• 2015

본 실험은 단기간 ABA처리가 토마토 묘의 생장과 증산율, 기공 저항성 및 건조 내성에 미치는 영향을 검토하기 위하여 수행되었다. 실험은 25일간 플러그 트레이에서 육묘한 토마토 묘를 간이 수경재배 키트에 이식하여 양액 육묘하면서 ABA처리 효과와 건조 내성을 검토하였다. 배양액에 ABA를 0.5, 1, 2, 및 $3mg{\cdot}L^{-1}$의 농도로 첨가한 4개의 처리구와 무처리구를 설계하여 5일과 10일간 양액육묘한 뒤 묘소질, 엽온, 증산율, 기공확산 저항성을 측정하였다. 건조 내성을 검토하기 위한 수분 스트레스 처리는 PEG 8,000을 이용하여 -5bar로 조정한 고삼투압 용액에 ABA처리 직후의 묘를 이식한 뒤, 묘의 위조 정도를 조사하였다. 저농도(0.5와 $1mg{\cdot}L^{-1}$)의 ABA처리구에서 묘소질은 경경을 제외하고 대부분의 생육에서 통계적 유의차는 나타나지 않았으나, 2와 $3mg{\cdot}L^{-1}$의 농도에서는 지상부의 생장이 억제되었다. 근권부의 생장은 $1mg{\cdot}L^{-1}$의 농도처리에서만 뿌리의 건물중과 생체중, 전표면적, 근장, 근경, root tip수 모두가 유의적으로 증가하였으며, 그 외의 처리농도에서는 일부의 생육지표를 제외하고는 유의적 차이가 나타나지 않았다. ABA처리 농도가 증가함에 따라 기공확산 저항성은 증가하고 증산율은 감소하는 경향을 보였다. 또, ABA처리는 묘의 건조 내성을 증가시켜 ABA가 첨가된 배양액에서 5일 또는 10일간 육묘한 묘를 -5bar 용액에 치상하였을 경우 대조구는 치상후 10시간 후부터 묘의 위조가 시작되어 20시간 후에는 모든 개체가 위조하였으나, ABA처리구는 치상 30시간 후부터 위조가 시작되어 50시간이 경과해서야 모든 개체가 위조되었다. 또, 수분 스트레스처리로 위조된 묘를 재관수하였을 경우 ABA 0.5와 $1mg{\cdot}L^{-1}$처리구는 100%, 그 이상 농도 처리구에서도 50%이상 회복되었으나, 무처리구의 경우는 전개체가 고사하였다. 이상의 결과 토마토 육묘과정에서 저농도의 ABA처리를 통한 근권부의 생장 촉진과 건조 내성 증진 가능성이 시사되었으나, 상업적 활용을 위해서는 추가적인 검토가 필요할 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1483-1489
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• 2016

Most of amino acid (AA) digestibility values for feed ingredients are obtained using pigs cannulated in the distal ileum. The ileal-cannulated pig model uses pigs older than six weeks due to difficulties related to implanting the T-cannula in distal ileum of younger pigs and complications during the post-surgical recovery. However, to properly formulate the diet of weaned pigs, the nutritive value of feed ingredients should be determined with younger pigs. Thus, 25 weaned pigs were used to determine the apparent total tract digestibility (ATTD) of nutrients, energy, and apparent ileal digestibility (AID) and standardized ileal digestibility (SID) ileal AA digestibility of broken rice (BR), with or without multicarbohydrase (MC) and phytase (Phy) supplementation. Piglets were weaned at 23 d of age and individually housed in digestibility cages until 45 d of age. The trial consisted of 7 d of adaptation to the experimental diets and 3 d of excreta (feces and urine) collection. Ileal digesta was collected at slaughter (about 6 weeks of age). A completely randomized experimental design was used to determine the effects of MC and Phy. Reference diets (RD, 5% casein) was replaced by 30% of BR with or without MC, Phy, or MC+Phy. The RD was used to quantify endogenous AA losses. BR with Phy supplied had increased the ATTD of dry matter (p<0.05) and SID of histidine (p = 0.05), arginine, leucine, lysine, valine, alanine, and proline (p<0.05). BR with MC had been increased digestible energy and protein and SID for histidine (p<0.05). There was no interaction between Phy and MC on the BR nutrient digestibilities. Standardized amino acid digestibilities of BR, without enzymes, were lower than those values reported in the literature. The MC and Phy improved the digestibility of some nutrients and energy of BR in post-weaned piglet diets.

• Parasites, Hosts and Diseases
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• 제37권1호
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• pp.13-19
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• 1999

The effects of in vitro culture methods on morphological development and infectivity of Strongyloides venezuelensis filariform larvae ($L_3$) to rats were investigated. A significantly higher body length was observed in $L_3$ from filter paper culture ($597.3{\;}{\pm}{\;}32.2{\;}{\mu\textrm{m}}$) than those in fecal (($509.9{\;}{\pm}{\;}35.0{\;}{\mu\textrm{m}}$) and nutrient broth culture (503.3{\;}{\pm}{\;}31.0{\;}{\mu\textrm{m}}) (P<0.05). Larval infectivity was assessed by exposing rats to 1,000 $L_3$ from each culture and worms were recovered from the lungs and small intestines. Recovery rate of these worms did not show any significant difference. A significantly greater body length of adults was recorded in those corresponding to the $L_3$ harvested from filter paper (2,777.5{\;}{\pm}{\;}204.4{\;}{\mu\textrm{m}}$) and nutrient broth culture (($2.732.5{\;}{\pm}{\;}169.8{\;}{\mu\textrm{m}}$) than those corresponding to the $L_3$ obtained from fecal culture (($2.600.5{\;}{\pm}{\;}172.4{\;}{\mu\textrm{m}}$) (P<0.05). Although worm fecundity and EPG counts differed among culture methods but worm burdens and course of infection did not. These findings suggest that the methods of cultures have a significant effect on the morphological development of the larvae to the $L_3$ stage, but do not influence the infectivity to rats.