• Journal of Chest Surgery
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• 제49권3호
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• pp.145-150
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• 2016

Background: Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods: Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous $O_2$ saturation, and lactate were measured. Results: The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion: After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow.

• 한국토양환경학회지
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• 제2권1호
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• pp.99-107
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• 1997

본 연구에서는 일련의 회분식 규모의 실험을 통해 소수성 유기오염물질로 오염된 토양에 토양세척기법을 적용함에 있어서 필요한 최적의 운전조건을 도출하고 세척후 분리된 상등액중에 포함된 유기오염물질 및 세척제를 유기용매를 이용하여 효율적으로 분리.회수하기 위한 방안을 모색하고자 하였다. 사용된 계면활성제는 토양과 결합될 우려가 적은 비이온계 계면활성제중 독성이 거의 없으며 국내에서 대량 생산되어 수급이 원활한 계면활성제를 선별하여 소수성 유기오염물질인 n-dodecane(4,000mg/kg dny Soil)으로 오염된 토양에 대해 세척시간, 계면활성제 용액의 농도, 진탕비, 온도 등에 따른 세척효율의 변화를 조사하였다. 실험결과 계면활성제의 HLB(hydrophile-liphophile balance)값이 MSR(molar solubility ratio) 값과 함께 토양세척시 중요한 변수로 작용하였다. HLB값이 낮아 유탁액을 형성하지 못하는 OA-5나 sophorolipid는 10% 이내의 극히 낮은 세척효율을 보였다. 그러나 안정된 유탁액을 형성하는 HLB값 범위내에서는 소수성 유기오염물질에 대한 액상실험에서의 용해도가 큰 계면활성제가 유리하였다. 높은 HLB값을 갖는 OA-14는 OA-9 보다 안정된 유탁액을 형성하지만 용해도에 대한 지표인 MSR값이 OA-9보다 작아 약 20%정도의 낮은 세척효율을 보였다. 안정된 유탁액을 형성하는 동시에 용해도가 높은 OA-9용액이 단독으로 쓰일 때는 최대 60%정도의 세척효율을 보였다. 또한 OA-9세척유출수로부터 유기용매인 벤젠을 이용하여 anthracene을 회수하고자 하는 경우, 세척유출수의 온도를 $30^{\circ}C$, pH는 2로 조절하는 것이 회수 효율 측면에서 바람직하다.

• 한국산림과학회지
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• 제105권2호
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• pp.202-207
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• 2016

곶감의 $SO_2$ 발생패드처리(SO2 0, 0.5, 1, 2 g/kg)에 의한 저장 중 품질에 미치는 영향을 조사한 결과, 저장기간동안 $SO_2$ 발생패드처리는 곶감의 중량 및 수분감소율과 가용성 고형물 함량에 영향을 미치지 않았다. 그러나 저장 12주 후 곶감 표면의 색차(E)는 무처리구에서 3.5로 가장 높은 반면, $SO_2$ 2 g/kg 처리구에서 2.6으로 가장 낮게 나타났다. 곶감의 갈변도는 저장 12주 후 무처리구에서 0.15 O.D.로 가장 높았으며, $SO_2$ 0.5 g/kg 처리구 0.14 O.D.와 $SO_2$ 1 g/kg 처리구 0.10 O.D., $SO_2$ 2 g/kg 처리구 0.05 O.D.순으로 나타났다. 부패율은 저장 12주 후 무처리구가 9.0%로 가장 높은 반면, $SO_2$ 2 g/kg 처리구는 부패가 전혀 발생되지 않았다. 모든 $SO_2$ 발생패드 처리구에서 곶감의 잔류 이산화황 농도는 3.3~97.0 ppm으로 안전한 범위에서 검출되었다. 따라서 $SO_2$ 발생패드처리는 곶감의 갈변 및 부패를 억제시킴을 확인하였으며 특히, $SO_2$ 2 g/kg 처리가 곶감의 품질유지와 저장성에 가장 효과적이라고 판단된다.

• 생태와환경
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• 제40권4호
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• pp.503-510
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• 2007

The purposes of the study were to analyze the seasonal effects on the fish fauna and compositions including trophic guilds and tolerance guilds. For the study, we collected fish samples twice in June as premonsoon period and early September 2007 as monsoon periods in five sampling sites of the Gap Stream, and then biological oxygen demand (BOD), nutrients (TN, TP) and suspended solids (SS) were compared with the guild data along the gradient of upstream-to-downstream. Chemical water quality, based on BOD, TP, and TN degraded gradually from the upstream to downstream reach and there were about 3 fold difference between S1 and S5. Water quality was worse in the premonsoon than the monsoon, and the heavy monsoon resulted in a dilution of the polluted river by rain water, especially, in the downstream reach. Total number of fish species, based on the catch per unit effort (CPUE), showed a distinct difference between the two seasons; 30 species were sampled in premonsoon, but 23 species were sampled in the monsoon, indicating a seasonal difference in the fish fauna. Tolerant species dominated the fish community (48.3%) in the stream, and the proportions prior to physical disturbance by the monsoon rain were evidently greater in the downstream reach than the upstream. This reflected the characteristics of urban stream polluted by nutrient enrichment as shown in the BOD and TP values. Sensitive species in the premonsoon decreased from the gradient of upstream-to-downstream reach. Such seasonal modifications in the trophic and tolerance guilds were evident. In the analysis of trophic guild and habitat guild, during the premonsoon the proportion of insectivore and riffle-benthic species were largely greater in the upstream reach than the downstream, whereas the proportions were opposite along the gradient of the stream in monsoon. Thus, the patterns of chemical water quality along the longitudinal gradients reflected the premonsoon conditions of insectivores and tolerant species, indicating that summer monsoon data of fish may not match with water quality due to large physical disturbance by flow regime. Seasonal monsoon in this region as well as the chemical pollution may act as a key role influencing the fish compositions of trophic and tolerance guilds and fauna. The data collected during the premonsoon rather than the monsoon, thus, may be better predictor for a diagnosis of stream health conditions.

• 생명과학회지
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• 제21권8호
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• pp.1156-1162
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• 2011

Equine herpesvirus type 3 (EHV-3)는 말[마(馬)]에서 말구진을 유발하고 말산업에 치명적인 악영향을 끼치는 매우 중요한 병원체이다. 국내에서 처음으로 말구진이 발생하였고, 말 생산농가에 경제적 피해를 입혔으나 다행히 원인바이러스 분리에 성공하였다. 이에 원인바이러스의 생물학적 특징을 연구하여 다음과 같은 결과를 얻었다. EHV-3를 RK-13 cell에 접종한 결과 접종 48 시간부터 세포변성효과가 나타남을 확인하였고 접종 72 시간부터는 세포박리가 일어났다. 세포를 수확하여 바이러스 DNA를 추출한 후 PCR 검사를 수행하였다. 그 결과 EHV-3에만 양성이었고 EHV-1 및 EHV-4에는 음성이었다. Swab에서 바이러스 DNA를 추출하여 10배씩 serial dilution을 한 후 PCR 검사를 실시한 결과 $10^4$까지 밴드를 확인할 수 있었다. 국내분리 EHV-3의 gG 특정부위에 대한 염기에서 표준주인 EHV-3 334/74 strain과 397개가 일치하여 99.25%의 상동성을 나타내었고 국내분리주를 EHV-3 거로주(Georo strain)라 명명하였다. 전기영동 결과에서는 EHV-3가 EHV-1보다 적은 수의 밴드를 확인할 수 있었다. 국내 분리주 EHV-3 거로주의 단백질을 분석한 결과 145 kD, 60 kD, 45 kD, 40 kD에서 단백 밴드를 관찰하였다.

• 식물병연구
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• 제12권3호
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• pp.240-248
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• 2006

Control of white rot which is one of the most serious apple diseases in Korea has mainly relied on periodical spray of protective fungicides. As the main inoculum source of the disease is pycnidiospores produced in the warts formed on affected stems of apple tree, it can be conceivable that inhibition of spore production might be an effective means for controlling the disease. Inhibitory efficacy of eight selected fungicides against sporulation of the fungus was assessed by counting the number of spores produced at detached warts treated with the fungicides of recommended dilution. They showed diverse effect on sporulation. Carbendazim and azoxystrobin suppressed sporulation almost completely, the former irreversively. Thiram and folpet promoted sporulation as producing much more number of spores than untreated control. Others showed almost no effect on sporulation. Effects of suppression and promotion in the sporulation shown by the fungicides on the control of white rot were examined by incidences of disease and infection at the plots adopted the spray programs of which the fungicide at late May was substituted by carbendazim, azoxystrobin, folpet and thiram, respectively. Disease incidence and infection frequency at the plots sprayed former two chemicals which suppressed sporulation were much lower than those of the plots adopted latter two chemicals and untreated plot at which the fungicide spray was skipped at that time. These facts were reconfirmed in the experiments conducted with carbendazim and thiram, in which 100 fruits were bagged just prior to each spray from late May to late July for elucidating the effect of the two fungicides on the action of subsequent ones. Disease incidence and infection frequency on the fruit bagged just prior to each spray were gradually increased as the seasons going on. The increase rate at the carbendazim plot was much lower than that of thiram. Especially, the fruit infected till late July at the carbendazim plot were almost completely cured by the three fungicides, iminoctadine-triacetate, tebuconazole and samzinwang, a combined formular of iminoctadine-triacetate and difenoconazole, sprayed at late July and hence. In thiram plot, infected fruit were also cured by the 3 fungicides but not remarkable. From these results, it can be concluded that control efficiency of white rot can be greatly enhanced by selecting the fungicide capable of suppress the sporulation of white rot fungus at the season when the mass dispersal of spores is not initiated.

• 식물병연구
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• 제26권2호
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• pp.61-71
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• 2020

당근검은잎마름병균인 Alternaria dauci KACC42997에 대해서 32개 살균제를 선발하여 균사생장 억제효과를 조사한 결과, '다2'군, '다5'군, '사1'군, '마2'군, '마3'군에 속하는 살균제의 균사생장 억제효과가 우수하였다. Iminoctadine tris-albesilate를 제외한 '카'군에 속하는 보호살균제와 '다3'군에 속하는 pyraclostrobin은 병원균의 포자발아를 억제하는 효과가 우수하였다. 균사생장 억제효과가 우수했던 숙신산탈수소효소 활성을 저해하는 '다2'군과 탈메틸효소 활성을 저해하는 '사1'군 살균제는 우수한 균사생장 억제효과를 보여주면서도, 포자발아 억제효과는 저조하였다. 하지만 '다5'군에 속하는 fluazinam은 균사생장 억제효과뿐만 아니라 포자발아 억제효과도 우수하였다. 특별히 '다2'군에 속하는 fluxapyroxad를 100 ㎍/ml 처리한 경우, 배지 상에서 포자형성을 47.1% 억제하였다. 구미, 평창, 제주 등에서 분리한 검은잎마름병균 집단의 '사'군, '다'군, '마'군 살균제에 대한 저항성 요인값을 비교하면, 제주 지역 병원균 집단의 저항성 요인값이 가장 낮았다. 평창 지역 균주 집단에서 '마2'군에 속하는 fludioxonil 저항성 균주가 2개 발견되었으며, 그들은 모두 iprodione과 procymidone에 대해서 교차저항성을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권4호
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• pp.536-542
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• 2007

The responses of whole body protein and glucose kinetics and of nitrogen (N) metabolism to non-protein energy intake (NPEI) were determined using an isotope dilution approach and measurement of N balance in three adult male goats. The diets containing 1.0, 1.5 and 2.0 times ME maintenance requirement, with fixed intake of CP (1.5 times maintenance) and percentage of hay (33%), were fed twice daily for each 21 d experimental period. After an adaptation period of 11 d, N balance was determined over 3 d. On day 17, whole body protein synthesis (WBPS) and glucose irreversible loss rate (ILR) were determined during the absorptive state by a primed-continuous infusion of [$^2H_5$]phenylalanine, [$^2H_2$]tyrosine, [$^2H_4$]tyrosine and [$^{13}C_6$]glucose, with simultaneous measurements of plasma concentrations of metabolites and insulin. Ruminal characteristics were also measured at 6 h after feeding over 3 d. Nitrogen retention tended to increase (p<0.10) with increasing NPEI, although digestible N decreased linearly (p<0.05). Increasing NPEI decreased (p<0.01) ammonia N concentration, but increased acetate (p<0.05) and propionate (p<0.05) concentrations in the rumen. Despite decreased plasma urea N concentration (p<0.01), increased plasma tyrosine concentration (p<0.05), and trends toward increased plasma total amino N (p<0.10) and phenylalanine concentrations (p<0.10) were found in response to increasing NPEI. Increasing NPEI increased ILR of both glucose (p<0.01) and phenylalanine (p<0.05), but did not affect ($p{\geq}0.10$) that of tyrosine. Whole body protein synthesis increased (p<0.05) in response to increasing NPEI, resulting from increased utilization rate for protein synthesis (p<0.05) and unchanged hydroxylation rate of phenylalanine ($p{\geq}0.10$). These results suggest that increasing NPEI may enhance WBPS and glucose turnover at the absorptive state and improve the efficiency of digestible N retention in goats, with possibly decreased ammonia and increased amino acid absorption. In addition, simultaneous increases in WBPS and glucose ILR suggest stimulatory effect of glucose availability on WBPS, especially when sufficient amino acid is supplied.

• 한국산학기술학회논문지
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• 제19권6호
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• pp.375-381
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• 2018

본 연구는 시설재배 아스파라거스를 대상으로 dinotefuran 수화제(10%)의 잔류특성을 규명하고, 그에 따른 안전사용기준 설정의 기초자료를 확보하고자 수행하였다. Dinotefuran의 잔류량은 7-8월 시설재배지의 아스파라거스를 입경 전과 후 상태가 되도록 제작하고, 수확 7일전 약제 2,000배 희석액을 1회 살포하여 1-2일 간격으로 5회에 거쳐 어린 순을 수확한 후 분석하였다. Dinotefuran의 분석에는 HPLC-UVD를 이용하였으며, 아스파라거스에서 dinotefuran 잔류분석법의 유효성은 두 수준 농도(0.5 및 1.0 mg/kg)의 회수율을 분석하여 평가하였다. 그 결과, dinotefuran의 정량한계는 0.01 mg/kg이었고, 분석법의 회수율은 두 수준 농도 각각 $83.3{\pm}0.4%$(변이계수 0.4%)와 $94.0{\pm}0.5%$(변이계수 0.5%)로 양호하였다. 입경 전 아스파라거스의 dinotefuran 잔류량은 약제 살포 후 5일이 경과하였을 때 유사농산물(엽경채류) 잔류허용기준 최저치를 기준으로 설정한 잠정잔류허용기준(0.05 mg/kg) 보다 낮은 수준(0.02-0.04 mg/kg)을 보였고, 입경 후 아스파라거스에서는 약제 살포 후 3일이 경과하였을 때 잠정잔류허용기준보다 낮은 수준(<0.01 mg/kg)을 보였다. 이러한 결과로 볼 때, 7-8월 시설재배지의 아스파라거스에 dinotefuran 수화제(10%)를 수확 7일전에 1회 살포하는 것은 아스파라거스의 농약잔류 안전성에 문제가 되지 않을 것으로 판단되었으며, 본 연구결과는 아스파라거스에 대한 dinotefuran의 안전사용기준을 설정하는데 중요한 기초자료가 될것으로 사료되어진다.

• Ocean and Polar Research
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• 제25권3호
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• pp.315-329
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• 2003

During the 1st Korea-Russia Arctic Expedition from 3 to 26 August, 2000 phytoplankton biomass and nutrient concentration were measured in the Barents and Kara Seas. Total of 57 surface samples were collected f3r the phytoplankton related measurements. Chlorophyll a (chi a) concentraitons were measured to investigate the relations between physico-chemical factors and phytoplankton biomass distribution. Chl a values ranged from 0.14 to $2.34mg\;m^{-3}$ (mean of $0.65{\pm}0.42mg\;m^{-3}$) over the surface stations. The elevated values of the chi a concentrations $(1.49{\sim}2.34mg\;m^{-3})$ were found in the southeastern Barents Sea near the Pechora River. Nanoplanktonic $(<20{\mu}m)$ phytoflagellates were the important contributors for the increase of the chi a. The nano-sized phytoflagellates accounted for more than 80% of the total chi a biomass in the study area. Mean chi a concentration in the Barents Sea $(0.72{\pm}0.57 mg\;m^{-3})$ was higher than in the Kan Sea $(0.52{\pm}0.45mg\;m^{-3})$, but there was no big difference between two areas. Surface temperatures and salinities ranged from 4.1 to $11.7^{\circ}C$ (mean of $8.8{\pm}1.9^{\circ}C$) and from 23.8 to 32.5psu (mean of $30.3{\pm}1.9^{\circ}C$ psu), respectively. The physical factors were not highly correlated with phytoplankton distribution. It is speculated that the insignificant correlation between phytoplankton biomass and physical factor was due to the same current which introduced similar water mass with higher water temperature and lower salinity into the study area. The mean values of major nutrients such as ammonia, nitrite, nitrate, phosphate, and silicate were $0.42{\pm}0.31{\mu}M,\;0.10{\pm}0.03{\mu}M,\;1.44{\pm}1.03{\mu}M,\;0.35{\pm}0.12{\mu}M,\;10.99{\pm}3.45{\pm}M$, respectively. The relations between phytoplankton biomass and nutrient concentration were not close, indicating that the surface nutrient concentrations during the study seem to be controlled by other physical factors such as input of fresh water (i.e. dilution effects).