• 한국축산식품학회지
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• 제32권1호
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• pp.62-67
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• 2012

This study calculated kinetic parameters of Escherichia coli O157:H7 and developed a probabilistic model to estimate growth probabilities of E. coli O157:H7 on polyethylene cutting boards as a function of temperature and time. The surfaces of polyethylene coupons ($3{\times}5$ cm) were inoculated with E. coli O157:H7 NCCP11142 at 4 Log $CFU/cm^2$. The coupons were stored at 13 to $35^{\circ}C$ for 12 h, and cell counts of E. coli O157:H7 were enumerated on McConkey II with sorbitol agar every 2 h. Kinetic parameters (maximum specific growth rate, Log $CFU/cm^2/h$; lag phase duration, h; lower asymptote, Log $CFU/cm^2$; upper asymptote, Log $CFU/cm^2$) were calculated with the modified Gompertz model. Of 56 combinations (temperature${\times}$time), the combinations that had ${\geq}$0.5 Log $CFU/cm^2$ of bacterial growth were designated with the value of 1, and the combinations that had increases of <0.5 Log $CFU/cm^2$ were given the value 0. These growth response data were fitted to the logistic regression to develop the model predicting probabilities of E. coli O157:H7 growth. Specific growth rate and growth data showed that E. coli O157:H7 cells were grown at $28-35^{\circ}C$, but there were no obvious growth of the pathogen below $25^{\circ}C$. Moreover, the developed probabilistic model showed acceptable performance to calculate growth probability of E. coli O157:H7. Therefore, the results should be useful in determining upper limits of working temperature and time, inhibiting E. coli O157:H7 growth on polyethylene cutting board.

• 한국환경농학회지
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• 제14권2호
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• pp.221-231
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• 1995

본(本) 연구(硏究)는 벼(Oryza sativa L. ; 품종명(品種名) : 동진벼 10일묘(日苗))를 공시작물(供試作物)로 하여 안개 및 비(非)안개 조건하(條件下)에서 생육반응(生育反應) 차이(差異)를 밝히고, 전형적(典型的)인 잡초종(雜草種)(피를 비롯한 6종(種)의 논 잡초(雜草))과의 경합양상(競合樣相)과 경합한계수준(競合限界水準)을 구명(究明)하여 안개 상습지(常習地)에서의 논 잡초방제체계(雜草防除體系) 확립(確立)을 위한 기초자료(基礎資料)를 마련할 목적(目的)으로 수행(遂行)되었다. 본(本) 연구(硏究)는 안개 제조(製造) 장치(裝置)가 설치(設置)된(Auto foggy system: SAE KI RTN Co.) 온실내(溫室內) Tray 시험(試驗)으로 수행(遂行)되었으며 시험결과(試驗結果)를 요약(要約)하면 다음과 같다. 실험(實驗) 1. 안개조건하(條件下)에서 수도(水稻)의 생장량(生長量) 차이(差異) 1) 안개조건하(條件下)에서의 초장(草長)의 차이(差異)가 없었고, 분얼수(分蘖數)는 적으나 유효분얼(有效分蘖) 비율(比率)이 높고 무효분얼(無效分蘖)이 억제(抑制)되는 경향(傾向)임. 2) 안개조건(條件)에서는 출수율(出穗率)이 감소(減少)되고 출수(出穗)가 지연(遲延)되는 경향(傾向)임. 3) 안개조건(條件)에서는 수도(水稻) 고건중(藁乾重)에는 차이(差異)가 없으나 수양구성요소(收量構成要素)인 수수(穗數), 1수당(穗當) 평균(平均) 영화수(穎花數), 천립중(千粒重) 및 등숙율(登熟率)이 감소(減少)하고 특히, 정조중(正祖重)과 현미중(玄米重)에서도 감소(減少)하는 경향(傾向)임. 실험(實驗) 2. 안개조건(條件)의 잡초경합(雜草競合) 양상(樣相)과 한계기간(限界期間) 1) 안개조건하(條件下)에서 경합기간별(競合期間別) 초장(草長)의 차이(差異)는 없었고, 분얼수(分蘖數)에서는 경합기간(競合期間)이 짧을수록 특히 무잡초구(無雜草區), 경합(競合) 20일구(日區)에서 안개로 인한 분얼수(分蘖數) 감소(減少)가 많음. 2) 안개조건(條件)에서는 출수율(出穗率)이 감소(減少)하고 특히 경합기간(競合期間)이 길어질수록(60일(日) 이상(以上)) 출수율(出穗率)이 떨어지고 출수개시(出穗開始)도 2-4일(日) 지연(遲延)되는 경향(傾向)임. 3) 안개조건하(條件下)에서 고건중(藁乾重)의 차이(差異)는 경합기간(競合期間)이 길어질수록(일(日) 이상(以上)) 차이(差異)가 크고, 수량(收量)의 차이(差異)는 경합기간(競合期間)이 무경합(無競合)(0일(日))과 40일(日) 이상(以上)에서 가장 심한 경향(傾向)임.

• 한국잡초학회지
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• 제17권3호
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• pp.295-302
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• 1997

잡초경합기간(雜草競合期間)이 찰옥수수 생육(生育) 및 수량(收量)에 미치는 영향(影響)을 구명하기 위하여 1995년에 수원(水原)에서 찰옥1호를 공시(供試)하여 무제초, 파종후 10, 20, 30, 40, 50, 60, 70, 80, 90일간 제초 및 완전제초에서의 잡초발생(雜草發生)과 옥수수 생육(生育) 및 수량(收量)을 조사(調査)한 결과를 요약하면 다음과 같다. 1. 공시포장(供試圃場)의 우점잡처(優占雜草)는 명아주, 피, 여뀌, 개기장 순(順)이었는데 명아주의 우점도(優占度)가 가장 높았다. 2. 발생(發生)한 잡초(雜草)의 형태적(形態的) 특성별(特性別)로 보면 광엽잡초(廣葉雜草), 화본과잡초(禾本科雜草), 사초과잡초(莎草科雜草)의 순이었다. 3. 찰옥수수 생육(生育) 및 수량에 영향(影響)을 미치는잡초(雜草)의 경합기간(競合期間)은 출사기(出絲期)가 파종후 30일간 제초하였을 때까지 였으나 간장, 수장, 이삭중, 주수 및 이삭수는 파종후 40일간 제초한 때까지였다. 4. 찰옥수수의 수량(收量)은 잡초(雜草)와의 경합기간(競合期間)이 길면 길수록 감수정도(減收程度)가 컸으며, 파종후 20일, 30일 및 40일간 제초구는 완전제초구에 비해 각각 76, 64, 33%가 감수(減收)되었으나 파종 후 50일간 제초구부터는 완전제초구와 수량(收量) 차이(差異)가 없었다. 5. 찰옥수수의 수량(收量)과 수량구성요서간(收量構成要素間)의 상관(相關)에서 수장(穗長), 이삭중(重), 주수(株數) 및 이삭수(數)가 고도(高度)의 정(正)의 상관(相關)을 보여 찰옥수수의 수량감소(收量減少)는 잡초(雜草)와의 경합(競合)에 의한 이 요인(要因)들의 감소(減少)에서 기인(起因)된 것으로 추정(推定)된다. 6. 잡초(雜草)에 의한 찰옥수수의 수량감소(收量減少)를 방지(防止)하기 위하여는 찰옥수수 파종후 50일까지의 잡초(雜草)는 제거(除去)하거나 발생(發生)을 억제하는 것이 필요한 것으로 사료(思料)된다.

• 한국농림기상학회지
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• 제17권4호
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• pp.281-289
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• 2015

일조시간 및 일사량은 작물생육에 중요한 기상요소이지만 기상청 동네예보 항목에 없기 때문에 3시간 간격 '하늘상태'를 활용하여 일조시간 및 수평면 일사량을 추정하는 방법을 고안하였다. 기상청 동네예보의 3시간 간격 '하늘상태' 자료를 수집하고 전국 22개 일사관측 기상대의 동시간대 실측 운량과 비교하여 '하늘상태'의 4단계 격자값 '맑음(1)', '구름조금(2)', '구름많음(3)', '흐림(4)'을 0부터 10까지의 운량으로 변환하였다. 22개 일사관측 기상대의 일 평균운량 0인 날에 대하여 일조율을 비교하여 관측여건이 가장 좋은 3개 지점을 선정하였다. 선정된 지점의 3년치 운량과 일조시간 실측자료로부터 운량-일조시간 추정식을 도출하였으며, 이 식에 의해 추정된 일조시간값으로 Angstrom-Prescott 모형을 구동하여 수평면 일사량을 산출하였다. '하늘상태' 기반으로 추정된 일조시간 및 일사량을 3 지점에서 2년간 실측자료와 비교한 결과 RMSE 기준 일조시간 추정오차는 1.5~1.7 시간, 일사량 추정오차는 $2.5{\sim}3.0MJ\;m^{-2}\;day^{-1}$ 이었다.

• 한국버섯학회지
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• 제8권4호
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• pp.137-141
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• 2010

1. 광 종류별 조도는 백색광은 2,270Lux로 가장 밝았으며, 황색광 1,750Lux, 청색광 460Lux, 적색광 400Lux의 순이었다. 2. 자실체 특성을 조사한 결과, CBM-1757이 느티만가닥버섯에 비하여 갓의 크기와 대직경이 양호한 경향이었으며, 광 종류간에는 황색광에서 다른 광에 비하여 다소 좋은 경향이었다. 3. 생육기간은 CBM-1757이 느티만가닥버섯에 비하여 균 배양일수는 2일, 초발이소요일수는 1일, 생육일수는 1일정도 단축되어 생육기간이 8일 정도 빠른 경향이었다. 광종류간에는 황색광에서 생육기간이 70일 소요되어 다른 광에 비하여 2~4일 정도 단축되는 경향이었다. 4. 유효경수 및 개체중은 품종간에 차이가 나지 않는 경향이었고, 병당 수량은 느티만가닥버섯 94.8g에 비하여 CBM-1757은 95.6g으로 약간 많았다. 광 종류간에는 백색광의 96.0g에 비하여 청색광 및 적색광에서는 2~9%가 감소되었으나, 황색광에서는 103.4g으로 8% 정도 증수되는 경향이었다. 5. 버섯의 색도는 CBM-1757이 느티만가닥버섯에 비하여 명도, 적색도 및 황색도가 높았으며, 광 종류간에는 황색광에서 다른 광에 비하여 다소 높은 경향이었다.

• 대한한방소아과학회지
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• 제31권4호
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• pp.31-38
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• 2017

Objectives The purpose of this study was to find out the clinically reliable relationships between the Risser sign and chronological age, bone age, menarche, and adult height prediction (AHP) and to evidence the reliability of the Risser sign. Methods This study had been carried out with 50 children who had their growth checked in an oriental medical hospital from January 2015 to February 2017. We investigated Risser sign in AP X-rays with iliac crest, bone age, AHP for all 50 children and the timing of menarche from the 22 girls in the study subjects. We also investigated a correlation between the Risser stage and the other indicators to analyze statistical data. Results The mean chronological ages of Risser 1, 2, 3 and 4 were 11.2, 12.6, 14.4, and 15.5 years respectively for the boys and 10.8, 12.2, 13.8 and 14.8 years respectively for the girls. The mean bone ages of Risser 1, 2, 3 and 4 were 12.3, 13.6, 15.7 and 16.5 years respectively for the boys and 11.7, 13.8, 14.3 and 14.9 years respectively for the girls. We analyzed 22 girls' Risser stages in accordance with the duration from menarche. The result showed that in the first six months after menarche, all girls were in Risser 1 and 2; in the next six months, the girls were in Risser 2 on average; in the next 12 months, all girls were in Risser 3 and 4; after more than two years from menarche, all girls were in Risser 4. The mean remaining growth height of Risser 1, 2, 3 and 4 were 27.8, 17.3, 4.4 and 1.0 cm respectively for the boys and 14.5, 5.1, 3.1 and 1.1 cm respectively for the girls. The Risser stage was correlated strongly with chronological age (Spearman's rho=0.707 (boy), 0.841 (girl)), bone age (Spearman's rho=0.869 (boy), 0.875 (girl)), duration from menarche (Spearman's rho=0.909) and remaining growth height (Spearman's rho=-0.784 (boy), -0.878 (girl)). Conclusions This study showed that the Risser sign can be useful in assessing skeletal maturity and predicting remaining growth height based on the Risser stage and the other growth indicators.

• Fisheries and Aquatic Sciences
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• 제9권4호
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• pp.160-166
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• 2006

We explored the possibilities of using the freshwater rotifer Brachionus angularis as a live food for small fishes cultured in fresh- or brackish waters. Brachionus angularis were collected from a reservoir for isolation and laboratory culture. Length and width of the lorica were $102.3{\mu}m$ and $76.6{\mu}m$, respectively, and those of amictic eggs were $64.4{\mu}m\;and\;47.9{\mu}m$, respectively. When their growth rates were examined at six different temperatures, i.e., 15, 20, 25, 30, 35, and $40^{\circ}C$, the highest daily growth rate of 0.801 was observed at $35^{\circ}C$, and growth was lower with decreasing temperature. Adaptation to salinity change was evaluated with two different modes of salinity increase: step-wise elevation lasting for short durations of 5 to 30 min or a long duration of 24 h. With the short duration modes, no individuals survived salinity higher than 10 psu, and the number of live individuals did not increase throughout the experiment. However, in the 24-h elevation, the number of individuals increased when salinity was elevated by 1 to 2 psu per day for the first 2 or 3 days, while no increase in number occurred at salinity increments higher than 3 psu per day. In addition, to assess the effect of different diets, four single-component diets (Chlorella vulgaris, Nannochloris sp., baker's yeast, or dry yeast) and three combination diets (C. vulgaris + Nannochloris sp. + baker's yeast + dry yeast; C. vulgaris 70% + baker's yeast 30%; C. vulgaris 30% + baker's yeast 70%) were used. The specific growth rates of B. angularis fed combination diets were higher than those of rotifers fed any single-component diet, with the highest rate of 0.648 in B. angularis fed a mixture of C. vulgaris, Nannochloris sp., baker's yeast, and dry yeast, and the lowest rate of 0.200 in those fed dry yeast only. Our results indicate that the freshwater rotifer B. angularis can be used for seedling production of both freshwater and brackish-water fishes that require small (less than about $120{\mu}m$) live food during their early stages.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제23권5호
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• pp.447-456
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• 2020

Purpose: Food insecurity, which is the inability to obtain food or inadequate food consumption in terms of quality and quantity, has physical and psychological consequences on children's health. This study aimed to investigate the relationship between children's growth disorders and food insecurity in Qazvin city, Iran. Methods: A case-control study was conducted on 177 cases and 355 controls of children aged 3 to 6 years, who were referred to health centers in Qazvin city. The case group consisted of children with growth disorders. Data were obtained with the 18-item US Department of Agriculture questionnaire, a household socioeconomic questionnaire, a and growth monitoring card. The data were analyzed with using IBM SPSS Version 22.0, by independent sample t-test, chi-square test, and logistic regression. Results: A significant relationship was found between children's growth disorders and household food insecurity with (p<0.05, odds ratio [OR]=17.0, confidence interval [CI]=5.9, 48.8) and without hunger (p<0.05, OR=2.69, CI=1.4, 4.9). There were also significant relationships between children's growth disorders and socioeconomic status (p<0.05, OR=3.4, CI=1.4, 8.5), the duration of breastfeeding (p<0.05, OR=0.94, CI=0.9, 0.98), and children's ages (p<0.05, OR=0.94, CI=0.92, 0.96). Sex and birth order, and the age of the parents was not found to be significantly related with growth disorders. Conclusion: Lower socioeconomic status and household food insecurity were the important predictors of children's growth disorders. Policymakers should focus more on promoting steady employment and income among family members. Nutritional education for mothers is also recommended, in order to better meet the nutritional needs of the children.

• 한국재료학회지
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• 제12권1호
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• pp.36-43
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• 2002

In this study, the nanosized ZnS thin films that can be used for fabrication of blue light-emitting diodes, electro-optic modulators, and n-window layers of solar cells were grown by the solution growth technique (SGT), and their surface morphology and film thickness and grain size dependence on the growth conditions were examined. Based on these results, the quantum size effects of ZnS were systematically investigated. Governing factors related to the growth condition were the concentration of precursor solution, growth temperature, concentration of aq. ammonia, and growth duration. X-ray diffraction patterns showed that the ZnS thin film obtained in this study had the cubic structure ($\beta$-ZnS). With decreasing growth temperature and decreasing concentration of precursor solution, the surface morphology of film was found to be improved. Also, the film thickness depends largely on the ammonia concentration. In particular, this is the first time that the surface morphology dependence of ZnS film grown by SGT on the ammonia concentration is reported. The energy band gaps of samples were determined from the optical transmittance values, and were shown to vary from 3.69 eV to 3.91 eV. These values were substantially higher than 3.65 eV of bulk ZnS. It was also shown that the quantum size effect of SGT grown ZnS is larger than that of the ZnS films grown by most other growth techniques.

• 한국작물학회지
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• 제44권2호
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• pp.149-153
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• 1999

Prediction of rice developmental stage is necessary for proper crop management and a prerequisite for growth simulation as well. The objectives of the present study were to find out the relationship between the plastochrone index(PI) and the developmental index(DVI) estimated by non-parametric phenology model which simulates the duration from seedling emergence(DVI=0) to heading(DVI=l) by employing daily mean air temperature and daylength as predictor variables, and to confirm the correspondency of developmental indice to panicle developmental stages based on this relationship. Four japonica rice cultivars, Kwanakbyeo, Sangpungbyeo, Dongjinbyeo, and Palgumbyeo which range from very early to very late in maturity, were grown by sowing directly in dry paddy field five times at an interval of two weeks. Data for seedling emergence, leaf appearance, differentiation stage of primary rachis branch and heading were collected. The non-parametric phenology model predicted well the duration from seedling emergence to heading with errors of less than three days in all sowings and cultivars. PI was calculated for every leaf appearance and related to the developmental index estimated for corresponding PI. The stepwise polynomial analysis produced highly significant square-rooted cubic or biquadratic equations depending on cultivars, and highly significant square-rooted biquadratic equation for pooled data across cultivars without any considerable reduction in accuracy compared to that for each cultivar. To confirm the applicability of this equation in predicting the panicle developmental stage, DVI at differentiation stage of primary rachis branch primordium was calculated by substituting PI with 82 corresponding to this stage, and the duration reaching this DVI from seedling emergence was estimated. The estimated duration revealed a good agreement with that observed in all sowings and cultivars. The deviations between the estimated and the observed were not greater than three days, and significant difference in accuracy was not found for predicting this developmental stage between those equations derived for each cultivar and for pooled data across all cultivars tested.