• 한국환경과학회지
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• 제19권2호
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• pp.217-227
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• 2010

This paper was studied $CO_2$ respiration rate with physicochemical properties of soils at wetland, paddy field and forest in Nongju-ri, Haeryong-myeon, Suncheon city, Jeollanam-do. Soil temperature and $CO_2$ respiration rate were measured at the field, and soil pH, moisture and soil organic carbon were analyzed in laboratory. Field monitoring was conducted at 6 points (W3, W7, W13, W17, W23, W27) for wetland, 3 points (P1, P2, P3) for paddy field and 3 points (F1, F2, F3) for forest in 10 January 2009. $CO_2$ concentrations in chamber were measured 352~382 ppm for wetland, 364~382 ppm for paddy field and 379~390 ppm for forest, and the average values were 370 ppm, 370 ppm and 385 ppm, respectively. $CO_2$ respiration rates of soils were measured $-73{\sim}44\;mg/m^2/hr$ for wetland, $-74{\sim}24\;mg/m^2/hr$ for paddy field and $-55{\sim}106\;mg/m^2/hr$ for forest, and the average values were $-8\;mg/m^2/hr$, $-25\;mg/m^2/hr$ and $38\;mg/m^2/hr$. $CO_2$ was uptake from air to soil in wetland and paddy field, but it was emission from soil to air in forest. $CO_2$ respiration rate function in uptake condition increased exponential and linear as soil temperature and soil organic carbon. But, it in emission condition decreased linear as soil temperature and soil organic carbon. $CO_2$ respiration rate function in wetland decreased linear as soil moisture, but its in paddy and forest increased linear as soil moisture. $CO_2$ respiration rate function in all sites increased linear as soil pH, and increasing rate at forest was highest.

• Journal of Ecology and Environment
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• 제33권2호
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• pp.165-173
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• 2010

Soil respiration ($R_S$) is a critical component of the annual carbon balance of forests, but few studies thus far have attempted to evaluate empirical regression models in $R_S$. The principal objectives of this study were to evaluate the relationship between $R_S$ rates and soil temperature (ST) and soil water content (SWC) in soil from a cool-temperate deciduous broad-leaved forest, and to evaluate empirical regression models for the prediction of $R_S$ using ST and SWC. We have been measuring $R_S$, using an open-flow gas-exchange system with an infrared gas analyzer during the snowfree season from 1999 to 2001 at the Takayama Forest, Japan. To evaluate the empirical regression models used for the prediction of $R_S$, we compared a simple exponential regression (flux = $ae^{bt}$Eq. [1]) and two polynomial multiple-regression models (flux = $ae^{bt}{\times}({\theta}{\nu}-c){\times}(d-{\theta}{\nu})^f:$ Eq. [2] and flux = $ae^{bt}{\times}(1-(1-({\theta}{\nu}/c))^2)$: Eq. [3]) that included two variables (ST: t and SWC: ${\theta}{\nu}$) and that utilized hourly data for $R_S$. In general, daily mean $R_S$ rates were positively well-correlated with ST, but no significant correlations were observed with any significant frequency between the ST and $R_S$ rates on periods of a day based on the hourly $R_S$ data. Eq. (2) has many more site-specific parameters than Eq. (3) and resulted in some significant underestimation. The empirical regression, Eq. (3) was best explained by temporal variations, as it provided a more unbiased fit to the data compared to Eq. (2). The Eq. (3) (ST $\times$ SWC function) also increased the predictive ability as compared to Eq. (1) (only ST exponential function), increasing the $R^2$ from 0.71 to 0.78.

• 미생물학회지
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• 제6권4호
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• pp.122-130
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• 1968

Action of various wavelengths of visible light on ultraviolet-radiation damage to haploid yeast cells, Saccharomyces cerevisiae 23971, was studied. The results were obtained on the basis of the survival and respiration rates by pre- and post-illuminations of various wavelengths before and after U.V.-irradiations on the yeast cells. Among the wavelengths tested, 635 $m{\mu}$, 429 $m{\mu}$ and white light which caused increase of respiration in pre-treatment alone, induced less resistance to the U. V.-damage than in the control, in both pre- and U.V.-treatment. On the contrary, such wavelengths as 574 $m{\mu}$and 530 $m{\mu}$, showing a weak effect on respiration in pre-treatment increased the susceptability to U.V.-radiation. Photoinactivation was generally obtained by both pre- and post- illuminations along with U.V.-treatment. At 635 $m{\mu}$ the PI rate was the lowest and also a low PI rate was shown at 429 $m{\mu}$. But 429 $m{\mu}$, in the post-treatment of the yeast cells pre-treated by the white light and the darkness respectively, showed the highest PI rate. In both pre- and post- treatment of 574, 530 and 473 $m{\mu}$,the PI rates were high to the same degree. Post-treatments of the wavelengths on U.V.-treated yeasts incubated rather under the white light than the darkness induced lower PI rate. It is assumed that there are great differences in action even of the same wavelength, depending upon the various combination of pre- and post-treatments, and that, moreover, the action of various wavelengths of visible light on U.V.-damage on the cells are concerned with the doses and dose rates of U.V. and visible lights. These observations led to an interpretation that each wavelength of visible light might exert distinctively different effects oil U. V.-damage, mainly causing the inhibition or stimulation of enzymes in the yeast cells.

• 한국식품저장유통학회지
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• 제3권1호
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• pp.55-60
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• 1996

To obtain the basic data on precooling effects for establishment the suitable postharvest handling technique or method of keeping high quality of vegetalble corn, the sweet, supersweet and waxy corn, (Danok #2, Cocktail #86 and Chalok #1), being mainly consumed as vegetables in Korea, were precooled with ice or vacuum cooling method immediately after harvest. The vacuum cooling was the most effective for the field heat removal of vegetable corn. It took only 30 min. at 4 to 5 torr of cold chamber pressure of vacuum precooler to lower the corn temperature from 30 to 2$^{\circ}C$. The ice cooling was also thought to be a useful precooling method with relatively short cooling time of 6 hrs. The vegetable corn treated with vacuum or ice cooling showed low and stable respiration rates of 25.5 to 43.5 CO2 mg/kg/hr. when stored at 0∼2$^{\circ}C$ while the samples stored at room temperature (20∼25$^{\circ}C$) without precooling were as high as 64.1 to 245 CO, mg/kg/hr.

• 한국환경농학회지
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• 제24권1호
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• pp.61-65
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• 2005

This study was to evaluate whether ionizing gamma radiation could be applied to break the dormancy of a potato minituber. The respiration rate of the minitubers was significantly affected by the storage temperature and a low dose gamma radiation. Ionizing radiation of 8 Gy enhanced the respiration rate of the potato tuber stored at $10^{\circ}C$ for 20 days. The potato tuber subjected to 4 and 8 Gy after 40 days storage at 10 and $20^{\circ}C$ exhibited higher respiration rates compared to the control (non-irradiated), but not at st. However, the ionizing radiation did not exhibit on significant effect on the respiration rate of the potato tuber stored for 60 days. It was observed that minitubers stored for 20 days had significant response to the storage temperature in terms of the total sugar content the higher the storage temperature, the lower the total sugar content. It was measured that the reducing sugar content was increased under the storage conditions both 5 and $10^{\circ}C$ for 40 days, but not to $20^{\circ}C$. The total sugar contents in the minituber stored for 60 days were similar to those stored for 40 days. The data was discussed on the relationships among the storage duration, temperature and ionizing radiation.

• Journal of Ecology and Environment
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• 제38권3호
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• pp.281-291
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• 2015

To clarify the effects of forest fire on the carbon budget of a forest ecosystem, this study compared the seasonal variation of soil respiration, net primary production and net ecosystem production (NEP) over the year in unburned and burned Pinus densiflora forest areas. The annual net carbon storage (i.e., NPP) was $5.75t\;C\;ha^{-1}$ in the unburned site and $2.14t\;C\;ha^{-1}$ in the burned site in 2012. The temperature sensitivity of soil respiration (i.e., $Q_{10}$ value) was higher in the unburned site than in the burned site. The annual soil respiration rate was estimated by the exponential regression equation with the soil temperatures continuously measured at the soil depth of 10 cm. The estimated annual soil respiration and heterotrophic respiration (HR) rates were 8.66 and $4.50t\;C\;ha^{-1}yr^{-1}$ in the unburned site and 4.08 and $2.12t\;C\;ha^{-1}yr^{-1}$ in the burned site, respectively. The estimated annual NEP in the unburned and burned forest areas was found to be 1.25 and $0.02t\;C\;ha^{-1}yr^{-1}$, respectively. Our results indicate that the differences of carbon budget and cycling between both study sites are considerably correlated with the losses of living plant biomass, insufficient nutrients and low organic materials in the forest soil due to severe damages caused by the forest fire. The burned Pinus densiflora forest area requires at least 50 years to attain the natural conditions of the forest ecosystem prior to the forest fire.

• Journal of Dental Anesthesia and Pain Medicine
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• 제18권2호
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• pp.97-103
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• 2018

Background: Respiration monitoring is necessary during sedation for dental treatment. Recently, acoustic respiration rate ($RRa^{TM}$), an acoustics-based respiration monitoring method, has been used in addition to auscultation or capnography. The accuracy of this method may be compromised in an environment with excessive noise. This study evaluated whether noise from the ultrasonic scaler affects the performance of RRa in respiratory rate measurement. Methods: We analyzed data from 49 volunteers who underwent scaling under intravenous sedation. Clinical tests were divided into preparation, sedation, and scaling periods; respiratory rate was measured at 2-s intervals for 3 min in each period. Missing values ratios of the RRa during each period were measuerd; correlation analysis and Bland-Altman analysis were performed on respiratory rates measured by RRa and capnogram. Results: Respective missing values ratio from RRa were 5.62%, 8.03%, and 23.95% in the preparation, sedation, and scaling periods, indicating an increased missing values ratio in the scaling period (P < 0.001). Correlation coefficients of the respiratory rate, measured with two different methods, were 0.692, 0.677, and 0.562 in each respective period. Mean capnography-RRa biases in Bland-Altman analyses were -0.03, -0.27, and -0.61 in each respective period (P < 0.001); limits of agreement were -4.84-4.45, -4.89-4.15, and -6.18-4.95 (P < 0.001). Conclusions: The probability of missing respiratory rate values was higher during scaling when RRa was used for measurement. Therefore, the use of RRa alone for respiration monitoring during ultrasonic scaling may not be safe.

• 한국농림기상학회지
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• 제9권3호
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• pp.203-208
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• 2007

본 연구에서는 동시에 여러 지점을 측정할 수 있는 open flow 시스템을 이용하여 소나무 줄기에서 발생하는 호흡을 겨울과 여름 두 시기에 측정하였다. 연구결과, 줄기의 목부조직에서 호흡속도($R_{stem}$)는 겨울에 $0.25-0.55{\mu}mol\;m^{-2}s^{-1}$, 여름에 $1.25-1.63{\mu}mol\;m^{-2}s^{-1}$의 범위를 나타냈다. 시기별 측정된 수목(15개체)간 $R_{stem}$의 변화성은 변동계수로 나타낼 수 있으며, 그 결과 여름과 겨울이 모두 23%로 시기에 따른 차이를 보이지 않았다. 이러한 변동계수 값에 근거하면 $R_{stem}$ 이 95% 신뢰수준에서 실제 값과의 차이가 10%와 20%보다 적기 위해서는 샘플링 수가 각각 최소 24개와 6개가 필요한 것으로 확인되었다. 또한 겨울과 여름의 온도와 개체간 평균 $R_{stem}$의 상관관계에서, $Q_{10}$ 값은 겨울이 1.49, 여름이 1.45로 계절간에 큰 차이를 나타내지 않았다. 그러나 $R_{20}$(줄기 온도 $20^{\circ}C$일 때의 $R_{stem}$)은 겨울($0.61{\mu}mol\;m^{-2}s^{-1}$)보다 여름($1.23{\mu}mol\;m^{-2}s^{-1}$)이 두 배 정도 컸다.

• 한국산림과학회지
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• 제83권2호
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• pp.221-228
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• 1994

소나무 유령목(幼齡木)의 생장(生長)에 따른 기관별(器官別) 호흡속도(呼吸速度)를 적외선(赤外線) $CO_2$ 가스 분석기(分析機)로 측정(測定)하여, 이 기초자료(基礎資料)를 Thornley의 생장식(生長式) $$R=(\frac{1-Yg}{Yg})\frac{dW}{dt}+mW$$에 적용(適用), 구성호흡(構成呼吸)에 관계되는 물질전환효율(物質轉換效率)(Yg), 유지호흡계수(維持呼吸係數)(m), 그리고 상대생장속도(相對生長速度)(${\mu}$)를 추정(推定)하였다. 물질전환효율(物質轉換效率) Yg는 0.3637g/g dw/yr, 유지호흡계수(維持呼吸係數) m는 0.094g/g dw/yr, 그리고 상대생장속도(相對生長速度) ${\mu}$는 0.90(2년생(年生))에서 0.33(11년생(年生))까지 연령(年齡) 증가(增加)에 따라 현저히 감소(減少)하는 경향을 보였다. 또, 소나무 유령목(幼齡木)의 총광합성량(總光合成量)(Pg)에 대한 총호흡량(總呼吸量)(R)의 비율(比率)(R/Pg)은 0.6~0.7 이었으며, 년간(年間) Pg의 64%가 새로운 물질(物質)을 구성(構成)하는 구성호흡(構成呼吸)으로 소비(消費)되었고, 체중(體重)(건물중(乾物重))의 3.4%가 유지호흡(維持呼吸)으로 소비(消費)되었다.

• 한국작물학회지
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• 제26권2호
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• pp.167-173
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• 1981

본 시험은 대두 종자의 호흡율의 품종간 차 및 종자 부위별 (자엽, 배축, 배꼽) 차를 검토하고, 이러한 호흡율의 차가 발아에 미치는 영향을 구명함으로서 효율적인 고발아성 종자의 초기 선발을 위한 기초적 자료를 얻고저 수행되었다. 1. 1시간 침종후 대두 종자의 흡수율은 종자부입별 및 품종간 차를 인정할 수 있었으나, 종자부위와 품종간 상호작용은 유의성이 없었다. 그러므로 종자부위와 품종은 대두 종자의 호흡에 독립적으로 작용하였다. 2. 자엽의 호흡율은 다른 부위, 즉 배축이나 배꼽에 비해 크게 높았으며 그 평균값은 자엽이 35.7, 배축이 28.0, 그리고 배꼽이 $23.9{\mu}hr^{-1}$ seed$^{-1}$이었다. 그러므로 대두 종자의 저장기관이 전체적으로 호흡에 주요한 영향을 미친다고 할 수 있다. 품종 Bonus는 다른 품종들에 비해 낮은 호흡율을 보였다. 3. 전체 대두 종자의 호흡율에 있어서 침종시간 및 시간과 품종간의 상호작용은 유의성이 인정되었으나 품종간에는 유의적인 차가 없었다. 4시간 침종 동안에 급격한 호흡율의 증가를 보였으며, 평균 호흡율 4시간에 13.6, 8시간에서 16.3, 12시간에서 17.8, 16시간에서 23.2, 그리고 24시간에 $25.3hr^{-1}$ seed$^{-1}$이었다. 4. 품종 Bonus에 있어서 종자 수분함량과 24시간 침종동안의 종자의 호흡률 간에는 유의적인 상관이 인정되었으나, 다른 품종들에 있어서는 상관계수 유의성이 없었다. 이 결과는 품종 Bonus는 다른 품종에 비해 24시간 침종동안 호흡에 보다 많은 수분을 요구한다고 생각한다. 5. 종자무게와 호흡률 간의 상관계수는 유의성이 없었으며, 이 결과는 대두 종자의 호흡률은 종자의 무게와 직접적인 관련이 없는 것으로 사려된다. 또한 호흡율과 3일간의 초기 초장의 신장간에도 유의적인 상관이 없었다.