• Journal of Sericultural and Entomological Science
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• v.18 no.2
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• pp.61-64
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• 1976

Experiments had been carried out in Suweon area from 1972 to 1973 to determine the seasonal fluctuation of Pseudodendrothrips mori NIWA using direct counts and to know the effects of chemicals for its control. 1. The fluctuation of mulberry thrips was especially influenced by precipitation and number of hours with sunshine in the meteological conditions. The peaks of fluctuation occurred several times but the highest peak occurred in late August. 2. The mulberry thrips was distributed in the range of the 4th to 16th leaves from the apex in a branch. The highest density leaves were 6th to 12th. 3. Orthene, Metasystox were the most effects on the mulberry thrips.

• Journal of Korean Society of Forest Science
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• v.107 no.1
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• pp.43-49
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• 2018

This study was conducted to investigate the effects of warming and precipitation manipulation on seasonal changes in fine root production (FRP) and fine root mortality (FRM) of 33-month-old Pinus densiflora seedlings for two years. The seedlings in warmed plots were warmed with $3.0^{\circ}C$ higher using infrared heaters. The air temperature of warmed (TW) plots was set to increase by $3^{\circ}C$ compared to temperature control (TC) plots, and the three precipitation manipulation consisted of precipitation decrease (-30%; PD), precipitation increase (+30%; PI) and precipitation control (0%; PC). FRP ($mm\;mm^{-2}\;day^{-1}$) was significantly altered by only precipitation manipulation (PC: 3.57, PD: 4.59, PI: 3.02), while warming had no significant effect on the FRP and FRM. Meanwhile, interactions between warming and precipitation manipulation and seasonal changes had no significant effects on FRP and FRM. However, the influences of seasonal changes in soil temperature and soil moisture on FRP and FRM were different according to warming. In TW plots, FRP showed a positive relationship with soil temperature, and FRM showed a negative relationship with soil moisture. On the other hand, in the TC plots, FRP showed a positive relationship with soil moisture, and there were no relationships between FRM and soil temperature and moisture. These results indicate that the climate factors that affect FRP and FRM might vary as the warming progresses.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.251-258
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• 1996

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.893-901
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• 2018

Influenza viruses that cause recurrent seasonal epidemics to humans can be controlled with vaccine and antiviral therapy. However, the medical treatments often exhibit limited efficacy in the elderly or immunosuppressed individuals. In these cases, daily uptake of probiotics may be an option to bring in health benefits against influenza. Here, we demonstrate the effects of probiotics Lactobacillus plantarum (Lp) and Leuconostoc mesenteroides (Lm) against seasonal and avian influenza viruses. As assessed by the plaque size reduction of human H1N1 and avian influenza H7N9 viruses, including green fluorescent protein-tagged H1N1 strain in cells, the selected Lp and Lm strains restrained viral replication in mouse lungs with statistical significance. Against lethal viral challenge, the Lp and Lm strains exhibited their beneficial effects by increasing the mean days and rates of survival of the infected mice. These results suggest that, despite rather narrow ranges of protective efficacy, the dietary supplement of Lactobacillus and Leuconostoc probiotics may promote health benefits against influenza.

• Journal of the Korean Institute of Gas
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• v.25 no.4
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• pp.1-9
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• 2021

The process and facilities of modern chemical plants are becoming increasingly complex, there is possibility of potential risk. Internal chemicals generate stress concentration when operated due to turbulence, laminar flow, pressure, temperature, friction, etc. It causes cumulative fatigue damage, which can damage or rupture chemical facilities and devices. The statistics of chemical accidents found that the highest rate of occurrence was in summer, and in the last five years statistics on chemical accidents, leakage incidents make up a decent percentage of accidents. Chemical leaks can cause serious human damage and economic damage, including explosions and environmental pollution. In this study, based on the leak accident of chemical plant, the risk analysis, and damage effects assessment were estimated using a 3D scanner and FLACS. As a result, if chemicals leak in summer, the risk is higher than in other seasons, the seasonal safety management measures, and countermeasure were estimated.

• Journal of Astronomy and Space Sciences
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• v.22 no.1
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• pp.69-88
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• 2005

This study was to understand the components that influence preservice secondary teachers' conceptions about 'seasonal changes' We selected 74 university science education students among whom 23 were in the second, 23 in the third, and 28 in the fourth year. The data collected from the paper-pencil test and individual interview with students. The results of this study show that the students had considerable apparent alternative conceptions, and that the 'distance theory' had most important effects on their alternative conceptions. It can be said that preservice secondary teachers' initial models of the seasonal change have their origin in their belief sets (specific theory) related to 'seasonal change', on the basis of which they can interpret their observations and cultural information with the constraints of a naive frame-work of physics. The structures and possible sources of their alternative conceptions for overcoming these alternative conceptions were also discussed. Implications for preservice science teacher education related to the results were discussed.

• Sleep Medicine and Psychophysiology
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• v.5 no.2
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• pp.170-176
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• 1998

Nowadays light therapy is accepted practice in the treatment for Seasonal Affective Disorder. The author reviewed the practical aspects of light therapy, latest treatment research on optimal parameters of light therapy and the mechanisms of action of light therapy. Therapeutic efficacy of light therapy using light visors & dawn simulators has been suggested but further studies are needed to clarify the efficacy. The treatment most strongly supported by research studies is light therapy using a light box to administer bright white light (2500 lux for 2 hours or 10000 lux for 30 minutes). Although some patients may be selective responders to morning light exposure, the optimal timing of light exposure still remains controversial. In practice, generally the duration of exposure can be increased or decreased as necessary and also the timing of exposure can be splitted (e.g. AM/PM usage) if optimal response is obtained. For most, a positive response of light therapy is usually noted within $4{\sim}5\;days$ and optimal response is obtained within 2 weeks. Generally the relapse of symptom occurs within days of discontinuation of light therapy, so to prevent relapse, light therapy should be continued throughout the winter season for typical seasonal affective disorder. Side effects of light therapy appear to be mild and well tolerated. Several theories for the mechanisms of action of light therapy at the basis of seasonal affective disorder had been suggested but remain still controversial. Further studies on the optimal parameters and the mechanisms of light therapy help us to better understand and treat not only seasonal affective disorders but also chronobiological disorders and nonseasonal affective disorders.

• Journal of Environmental Health Sciences
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• v.44 no.6
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• pp.572-580
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• 2018

Objectives: Human biomonitoring (HBM) is a measurement of the chemicals and their metabolites in human biological samples and has been successfully employed to determine the exposure levels of environmental chemicals. In this study, we analyzed seasonal variations of the blood or urinary levels of chemicals, and assessed that these differences could affect the results of association study. Methods: The Korea National Environmental Health Survey (KoNEHS) is a nationwide survey that analyzes exposure levels of environmental pollutants, 19 kinds of chemicals including heavy metals and organic chemicals, and the exposure factors in the general population. Based on KoNEHS data, we analyzed the levels of chemicals concentrations over the total survey period (2012-2014) and each season, and assessed the association of thyroid measures with phthalate metabolite and BPA. Results: Exposure levels of blood mercury and lead were lower in summer compare to winter. Bisphenol A and PAHs metabolites were higher in spring and summer, but lower in autumn. VOCs metabolites were generally lower in summer and autumn. Phthalate metabolites were higher in all other seasons than in winter. Pyrethroid metabolite, 3-PBA, was higher in summer and autumn. Regarding seasonal variation of chemical exposures, the statistical significance and size of effects between thyroid measures and phthalate and BPA were changed with season. Conclusion: Seasonal variations of chemical exposure and health outcome should be considered for interpreting biomonitoring results from a public health context.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.315-323
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• 2018

BACKGROUND/OBJECTIVES: Available data suggest that seasonal changes may influence the nutritional status and overall health of elderly individuals. Therefore, this study was conducted to investigate the effects of seasonal changes and related factors on energy and nutrient intake of older adults. SUBJECTS/METHODS: Individuals aged 65 years or over were prospectively enrolled in this single-center study (male: 11, female: 20). Data were collected between May 2013 and February 2014 during winter, spring, summer and autumn. Food consumption and biochemical parameters were taken during each season to assess the seasonal nutrition status of the elderly. Upon analysis of biochemical parameters (retinol, vitamin D and vitamin C), an high-performance liquid chromatography device was utilized whereas an Immulite 2000 device was utilized during analysis of serum folic acid and parathyroid hormone. RESULTS: Fruit, fat, egg and bread consumption varied seasonally in males and females (P < 0.05). During winter, daily energy intake was found to be greater than in other seasons in males (557 kcal) and females (330 kcal) (P < 0.05). Additionally, carbohydrates, vegetable protein, n-3 fatty acid and sodium intake increased in winter, while the n-6/n-3 ratio increased in summer among males (P < 0.05). Dietary fiber and sodium intake in winter, vitamin C, iron and zinc intake in spring, and cholesterol, retinol, vitamin D and niacin intake in autumn were found to be higher in females when compared to other seasons (P < 0.05). Serum parathyroid hormone level was higher in winter, and vitamin D level was higher in autumn in both genders (P < 0.05). In males, blood folic acid level was higher in winter, while vitamin C level was higher in females, and there was no seasonal variation in retinol concentration (P < 0.05). CONCLUSION: Food consumption and biochemical parameters showed significant seasonal variations in older adults. It is not clear if nutrition plans in older adults will benefit from consideration of seasonal changes in eating habits.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.3
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• pp.163-172
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• 2015

This study examined the potential effects of urban growth on streamflow in the Gyungan River watershed, Korea, using urban containment scenarios. First, two scenarios (conservation and development) were established, and SLEUTH model was adapted to predict urban growth into the year 2060 with 20 years interval under two scenarios in the study area. Urban growth was larger under scenario 2, focusing on development, than under scenario 1, focusing on conservation. Most urban growth was predicted to involve the conversion of farmland, forest, and grasslands to urban areas. Streamflow in future periods under these scenarios was simulated by the Soil and Water Assessment Tool (SWAT) model. Each scenario showed distinct seasonal variations in streamflow. Although urban growth had a small effect on streamflow, urban growth may heighten the problems of increased seasonal variability in streamflow caused by other factor, such as climate change. This results obtained in this study provide further insight into the availability of future water resource and can aid in urban containment planning to mitigate the negative effects of urban growth in the study area.