• 한국농림기상학회지
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• 제11권4호
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• pp.127-134
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• 2009

본 실험은 '후지'/M.9 재배체계에 있어 최근 문제시되는 일소증상 발생에 미치는 한여름의 기온 요인을 구명하기 위하여 실시되었다. 일소증상은 최고기온이 $31^{\circ}C$이상인 누적일수 및 하루 누적 총광량이 많을수록 발생이 증가하였다. 상대적으로 개방된 수관을 형성한 '후지'/M.9은 '후지'/M.26보다 과실이 광에 노출되기 쉬워 일소증상 피해가 더 컸다. '후지'/M.9 사과나무 중에서는 과대지 길이가 짧은 나무에서 일소증상 피해가 더 컸다. 일소증상 발생은 재배지역 및 재식 열방향에 영향을 받지 않았고, 주로 남쪽과 서쪽에 착과 된 과실에서 일소증상 발생이 많았다. 그 이유는 과실이 직사광선에 노출되어 과실온도가 $40{\sim}45^{\circ}C$를 넘었기 때문으로 판단되었다.

• 생물환경조절학회지
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• 제31권4호
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• pp.261-269
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• 2022

본 연구는 '암기조생' 감귤 과실의 표면온도와 일사량 간의 상관관계를 분석하여 일소가 유발되는 과실 표면온도를 예측하고 일소 발생을 경감시키고자 수행하였다. 이를 위해 기온이 31℃일 때 30분 간격으로 5분 미세살수와 1% 탄산칼슘, 4% 카올린 용액을 10일 간격으로 3회 엽면살포하여 일소과 발생과 과실 품질을 조사하였다. 과실 표면온도는 일사량과 R = 0.788(p < 0.01)로 유의한 정의 상관관계를 나타냈으며 한낮에는 기온보다 최고 16℃가 높았다. 과실 표면온도를 추정하는 회귀식 y = 0.099 × (대기온도) + 0.018 × (일사량) + 20.779(R = 0.687, p < 0.01)을도출하였다. 30분 간격으로 5분 미세살수시수관 내부 온도가 무처리보다 5.1℃ 낮았다. 일소과 발생률은 미세살수구가 2.1%로 무처리구보다 2배 이상 낮았고 통계적으로 유의성을 나타냈으나, 과실 품질은 처리간에 비슷하였다. 햇빛을 반사하거나 미세살수를 실시하여 과실 표면온도를 낮추면 일소 발생을 줄일 수 있을 것으로 보인다.

• 한국농림기상학회지
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• 제12권2호
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• pp.76-82
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• 2010

본 연구는 '후지'/M.9 재배에 있어 최근 문제시 되는 일소 발생 경감 기술을 비교 분석하기 위하여 3년 (2001~2003) 동안 수행하였다. 일소는 과실 성숙기에 높은 온도와 일사광에 의해 과실 온도가 $40{\sim}45^{\circ}C$에 달할 경우 발생하므로 과실 온도를 효과적으로 줄이는 것이 매우 중요하다. 이에 6월말 이후 흰색 코팅제인 카올린 및 탄산칼슘을 2주 간격으로 4회 처리한 실험과 7월 말에서 8월 중순 사이에 기온이 $31^{\circ}C$ 이상일때 미세살수 한 실험 결과를 분석해 본 결과, 두 실험 모두 일소 발생이 현저하게 감소되면서 과실품질이 향상된 것으로 나타났다. 이는 이들 처리들이 과실과 잎의 온도를 감소시켜서 광합성 능력이 증가했기 때문인 것으로 판단되었다.

• 한국연초학회지
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• 제17권1호
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• pp.15-19
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• 1995

This study was made of the effects from exposure to air temperature and amount of solar radiation during the wilting period on the sunburn of burley tobacco. Tobacco stalks were cult with one hour interval from 8:00 to 16:00, and were left on the field to expose to weather, and tobacco single leaf placed under 4 temperatures regimes in indoor. Sun-burn of the leaves was occurred when the leaves were exposed to temperature higher than 33$^{\circ}C$, and to solar radiation more than 800w/$m^2$ between 11:00-15:00 in a day during the curing season. The leaf temperature was increased until 52$^{\circ}C$ under the weather condition. The tobacco leaves were also burned without solar radiation when the leaves were exposed to high temperature until 5$0^{\circ}C$ of leaf temperature. Sun-bum was increased at upper leaves and at higher moisture content of leaf.

• 대한수의학회지
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• 제45권1호
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• pp.1-6
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• 2005

In this study we assessed the influences of ultraviolet (UV) light B radiation on epidermal cells by apoptotic sunburn cell (SBC) and the effect of green tea treatment on the inhibition of SBC formation in SKH1-hr mouse. The extent of changes following $200mJ/cm^2$ (0.5 mW/sec) was studied at 0, 3, 6, 12, 18, 24, 30 or 36 hours after exposure. SBCs were recognized by 3 hours after irradiation. There was tendency to increase from 3 hours to 24 hours and decrease from then to 36 hours after irradiation. The mice that received 0, 25, 50, 100, 200, 400 or $800mJ/cm^2$ of UVB were examined 24 hours after irradiation. The SBCs were induced as the radiation dose increases from 0 to $200mJ/cm^2$. A further increase of radiation dose has little further effect. The frequency of UVB ($200mJ/cm^2$)-induced SBC formation was reduced by intraperitoneal injection of green tea extract (p<0.01).

• Safety and Health at Work
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• 제12권2호
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• pp.244-248
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• 2021

Background: Sunburn is the main avoidable cause of skin cancer. Beach lifeguards spend many hours exposed to the effects of solar radiation during their work day, precisely at times of the year when levels of solar irradiation are highest. The aim of this study is to quantify the risk to beach lifeguards of sun exposure. Methods: A descriptive cross-sectional study was carried out in the Western Costa del Sol, southern Spain, during the summer of 2018. The research subjects were recruited during a skin cancer prevention course for beach lifeguards. All participants were invited to complete a questionnaire on their habits, attitudes, and knowledge related to sun exposure. In addition, ten were specially monitored using personal dosimeters for three consecutive days, and the results were recorded in a photoprotection diary. A descriptive analysis (mean and standard deviation for the quantitative variables) was performed, and inter-group differences were evaluated using the Mann-Whitney U test. Results: Two hundred fifteen lifeguards completed the questionnaire, and 109 met the criteria for inclusion in this analysis. The mean age was 23.8 years (SD: 5.1), 78.0% were male, 71.5% were phototype III or IV (Fitzpatrick's phototype), and 77.1% had experienced at least one painful sunburn during the previous summer. The mean daily personal ultraviolet exposure per day, the minimal erythema dose, and the standard erythema dose, in J/m², were 634.7 [standard deviation (SD): 356.2], 2.5 (SD: 1.4) and 6.35 (SD: 3.6), respectively. Conclusion: Beach lifeguards receive very high doses of solar radiation during the work day and experience correspondingly high rates of sunburn. Intervention strategies to modify their sun exposure behavior and working environment are necessary to reduce the risk of skin cancer for these workers and to promote early diagnosis of the disease.

• 농업과학연구
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• 제49권3호
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• pp.561-570
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• 2022

This study investigated the changes in planting environment and growing conditions of 'Arisoo' apple trees under shading net treatments. Apple tree canopies were fully covered with Blue (blue color net, mesh size: 4 mm × 5 mm), Black-A (black color net, mesh size: 4 mm × 5 mm), Black-B (black color net, mesh size: 5 mm × 6 mm), and uncovered trees were used as the control. Inside the tree canopies, the illuminance was observed as 100% (85.0 Klux) in the control, but it decreased to 75% (64.3 Klux) in the Blue, 73% (63.0 Klux) in the Black-A, and 77% (65.9 Klux) in the Black-B nets, respectively. The solar irradiance was observed as 755 w·m^-3 in the control, but it was decreased to 715 w·m^-3 in the Blue, 624 w·m^-3 in the Black-A, and 647 w·m^-3 in the Black-B nets, respectively. The average daily temperature was observed to be the highest in the Black-A net (31.8℃) while it was observed to be around 30.0℃ in the control, Blue, and Black-B nets. In addition, the average fruit surface temperature was observed to be the highest (39.4℃) in the control, but it was decreased to 38.1℃ in the Blue, 37.3℃ in the Black-A, and 39.0℃ in the Black-B nets. However, the average soil temperature, the shoot growth rate, and leaf SPAD values were not different in all the treatments. Fruit sunburn disorders were the highest in the control while it was observed to be lower in the fruits from trees covered with the shading nets. However, at harvest, the fruit quality parameters were not different in all the treatments. Overall, this study suggests that the apple trees covered with the shading nets reduced the illuminance, solar irradiance, fruit surface temperature, and fruit sunburn disorders. However, the shading nets did not affect tree growth and apple fruit quality.

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2015년도 하계 학술발표논문집
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• pp.156-160
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• 2015

• 한국연초학회지
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• 제22권2호
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• pp.138-142
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• 2000

The effects of stalk cutting time and environmental factors such as air temperature, leaf temperature, solar radiation and leaf moisture content during harvesting and curing in burley tobacco(Nicotiana tabacum L.) on weight loss of fresh stalks and sunburning in leaves were investigated at Chonju Experiment Station, Korea Ginseng & Tobacco Research Institute in 1996 and 1997. Twelve to fifteen percent of the fresh weight was lost in 3 to 4 hours after stalk-cutting, and sunburned leaves could be observed in case of stalk cutting between 11:00 and 15:00 O'clock on a clear sunny day, when the air temperature was 34 to 35$^{\circ}C$, leaf temperature 52 to 54$^{\circ}C$, and solar radiation 700 to 940 w/$m^2$. The leaves exposed to this weather condition were sunburned within 1 hour after stalk cutting. But low temperature (below $25^{\circ}C$) with high solar radiation(above 700w/m2) or high temperature(above 3$0^{\circ}C$) with low solar radiation (below 600w$m^2$) did not induce the sunburn damage in leaves. As the leaf temperature and leaf moisture content were higher, the sunburned leaves increased. The leaves at the higher stalk position were more easily sunburned than those at the lower. This result indicates that the immature leaves with higher chlorophyll content might be more susceptible to sunburning.

• Journal of Photoscience
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• 제9권2호
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• pp.197-200
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• 2002

UVR-induced immunosuppression contributes to skin cancer. The aim was to construct accurate dose response curves for primary and secondary contact sensitivity for solar-simulated UVR (ssUVR; 290-400nm), UVA and UVB as the role of UVA in immunosuppression is controversial. We used a xenon arc source. The mice were immobilised, enabling accurate dosing. C57BL/6 mice were immunosuppressed at half the dose of ssUVR required to cause sunburn but not by higher doses (up to the sunburn dose). Thus, ssUVR causes systemic immunosuppression only over a narrow, low dose range. UVA caused suppression at low but not high doses whereas UVB induced immunosuppression at all doses tested. 8 weeks later the mice were resensitised to assess tolerance. Mice exposed to the minimum immunosuppressive dose of ssUVR prior to primary sensitisation were tolerant to re-sensitisation. However, at higher doses of ssUVR, these mice were protected from tolerance. Interestingly, while low doses of UV A caused immunosuppression, even lower doses enhanced the response to the second sensitisation. Higher doses of UVA had no affect. UVB induced tolerance in a dose related manner. Thus, ssUVR only induces immunosuppression and tolerance over a narrow dose range. Both UVA and UVB are immunosuppressive at this dose, while higher doses of UVA protect from the suppressive effects of UVB. Surprisingly very low doses of UVA enhanced memory development. Thus UVR has complex effects on the immune system depending on dose and spectrum.