• Korean journal of applied entomology
• /
• v.47 no.2
• /
• pp.163-168
• /
• 2008

Temperature dependent development of Tetranychus. urticae Koch was studied on the leaf of eggplant at 17, 22, 27, 32 and $37^{\circ}C$. T. urticae showed a minimum mortality at $27^{\circ}C$ and it increased at higher or lower temperatures than $27^{\circ}C$. The hatchability was low at 17 and $37^{\circ}C$. The duration of development decreased with increasing temperatures i.e., 5.3d at $37^{\circ}C$ and 25.8d at $17^{\circ}C$. Linear regression analysis of temperature vs. rate of development yielded the higher $r^2{\geq}0.88$ resulting in a good fit of the estimated line in the range of $17{\sim}37^{\circ}C$. Developmental zero temperature was $12.5^{\circ}C$ for the entire immature stage of female and $12.8^{\circ}C$ for that of male. Thermal constants were 80.5 and 74.7 degree days for those of female and male, respectively. Adult life span and oviposition period decreased with increasing temperatures. The number of eggs laid per female peaked at 141.0 eggs at $27^{\circ}C$, while that was a minimum 78.0 eggs at $37^{\circ}C$. Rate of hatchability, ratio of female, and $R_o$ were increased up to $27^{\circ}C$, and than declined thereafter. Intrinsic rate of natural increase (Rm) increased with rising temperatures and showed a maximum 0.5652 at $37^{\circ}C$. Also, ${\lambda}$ increased with increasing temperature. Doubling time (Dt) and generation time (T) decreased with increasing temperature.

• Journal of Bio-Environment Control
• /
• v.29 no.2
• /
• pp.161-170
• /
• 2020

There is systematic spatial variations in environmental properties due to sensitive reaction to external conditions at plastic greenhouse occupied 99.2% of domestic agricultural facilities. In order to construct 3 dimensional distribution of temperature, relative humidity, CO₂ and illuminance, measurement matrix as 3 by 3 by 5 in direction of width, height and length, respectively, dividing indoor space of greenhouse was designed and tested at experimental site. Linear regression analysis was conducted to evaluate optimal estimation method in terms with horizontal and vertical variations. Even though sole measurement point for temperature and relative humidity could be feasible to assess indoor condition, multiple measurement matrix is inevitably required to improve spatial precision at certain time domain such as period of sunrise and sunset. In case with CO₂, multiple measurement matrix could not successfully improve the spatial predictability during a whole experimental period. In case with illuminance, prediction performance was getting smaller after a time period of sunrise due to systematic interference such as indoor structure. Thus, multiple sensing methodology was proposed in direction of length at higher height than growing bed, which could compensate estimation error in spatial domain. Appropriate measurement matrix could be constructed considering the transition of stability in indoor environmental properties due to external variations. As a result, optimal measurement matrix should be carefully designed considering flexibility of construction relevant with the type of property, indoor structure, the purpose of crop and the period of growth. For an instance, partial cooling and heating system to save a consumption of energy supplement could be successfully accomplished by the deployment of multiple measurement matrix.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1977.06a
• /
• pp.4.4-5
• /
• 1977

The vibratory energy introduced into the external ear canal is changed by the mechanical factors of eardrum itself, the motility of ossicles, and the air cushion of tympanic cavity and the like. This study was designed to investigate the volume of middle ear cavity and mastoid air cell system as a factor of determining the accoustic impedance of middle ear system. The author studied how the increase in air volume of middle ear cavity effects on the acoustic impedance of middle ear system with dogs' ears and researched the correlation between the degree of pneumatization of temporal bones and the acoustic impedance of middle ear system by comparing the radiological findings of pneumatization (Law's and Towne's projection) with the acoustic impedance measurements with Madsen ZO 70. The result is as follows: 1 The tympanometric findings in control state revealed the curves of type A, and did not change in its configuration by the increase in the air volume of dogs middle ear system. 2. The static compliance of middle ear revealed a distinct and linear increase in proportion to the increase in air volume of middle ear system; the rate of increase was $0.05{\pm}0.02$ cc of static compliance per cc of air volume. 3. Authenticated in the above result and the tendency to increase in static compliance in proportion to the increase in the degree of pneumatization of temporal bones, there was significant regression equation between the degree of pneumatization of temporal bones (x variable) and the static compliance of middle ear system; $y=0.19x{\pm}0.16{\pm}0.05$ It is suggested that the difference in volume of middle ear system plays an important role in the change of the static compliance of middle ear, and the author concludes that the measurement of static compliance of middle ear has clinical value as diagnostic means of evaluating the degree of pneumatization of temporal bones along with some radiological examination.

• Journal of dental hygiene science
• /
• v.18 no.4
• /
• pp.210-217
• /
• 2018

Periodontal disease is a chronic inflammatory disease that affects quality of life and nutrition. Several studies have demonstrated a link between periodontal disease and low bone density, and vitamin D is expected to have a beneficial effect on periodontal disease as well as on bone mineral density and anti-inflammatory effects. The purpose of this study was to identify the association between periodontal disease and vitamin D because the results are different in some studies and there is a lack of research in Korea. In this study, we conducted a multiple linear regression analysis of 8,783 subjects among 23,626 subjects who were older than 20 years of age, who had serum vitamin D levels and periodontal disease, who had three years of the National Health and Nutrition Survey that was conducted in Korea from 2012 to 2014. We examined the relationship between serum vitamin D levels and periodontal disease. Tooth loss and vitamin D levels were negatively correlated (${\beta}=-0.028$, p=0.008). In addition, the prevalence of periodontal disease was found to be higher in men younger than 50 years of age with lower vitamin D levels (Q1: 1.769 [1.125~2.782], Q2: 1.182 [0.743~1.881], Q3: 0.676 [0.400~1.881]; p=0.001). Low vitamin D levels and periodontal disease are common diseases in primary care. Vitamin D supplementation is expected to have favorable effect on periodontal disease and falls, osteoporosis, osteoarthritis, and cancer. Therefore, patients with periodontal disease may benefit from periodic vitamin D management to improve quality of life as well as to manage periodontal disease. In addition, as shown in this study, not only elderly individuals, but also men younger than 50 years of age are related to periodontal disease, so there should be interest in controlling the levels of vitamin D in adults.

• Journal of agricultural medicine and community health
• /
• v.25 no.1
• /
• pp.11-21
• /
• 2000

This study was conducted to reveal the effects of musculoskeletal risk factor on farmer's syndrome. We sampled 97 farmers aged above 30 in 3 villages of Kyunggi-do. Self-administered questionnaire for general characteristics, farmer's syndrome, musculoskeletal risk factor, blood pressure, and laboratory tests were conducted. According to the score of musculoskeletal risk factor, we divide the subjects high risk group and low risk group. The most common musculoskeletal risk factor is repetitiveness, bending of waist and rapid movement in order. The prevalence of farmer's syndrome of all subjects is 28.9%. In female the prevalence of farmer's syndrome(45.2%) is higher than in male(16.4%) significantly. High musculoskeletal risk group had higher score of farmer's syndrome(5.9) than low musculoskeletal risk group(4.4). The most common symptom is lumbago(76.3%), the second was numb limb and shoulder stiffness(54.6%, 54.6%). The prevalence of numb limb and shoulder stiffness higher in high musculoskeletal risk group than low musculoskeletal risk group, but that of lumbago did not show significant differences. In linear regression, score of farmer's syndrome was related to musculoskeletal risk factor as well as gender. Blood pressure and laboratory test did not show significant differences between two groups. These results suggest that musculoskeletal risk factor would influence farmer's syndrome. Further ergonomic evaluation and intervention of farmer's works and musculoskeletal diseases are needed.

• Journal of Korea Water Resources Association
• /
• v.39 no.5 s.166
• /
• pp.453-466
• /
• 2006

The objective of this study was to analyze the changes in the hydrological environment in Soyanggang-dam watershed due to climate change results (in yews 2050 and 2100) which were simulated using CCCma CGCM2 based on SRES A2 and B2. The SRES A2 and B2 were used to estimate NDVI values for selected land use using the relation of NDVI-Temperature using linear regression of observed data (in years 1998$\sim$2002). Land use change based on SRES A2 and B2 was estimated every 5- and 10-year period using the CA-Markov technique based on the 1985, 1990, 1995 and 2000 land cover map classified by Landsat TM satellite images. As a result, the trend in land use change in each land class was reflected. When land use changes in years 2050 and 2100 were simulated using the CA-Markov method, the forest class area declined while the urban, bareground and grassland classes increased. When simulation was done further for future scenarios, the transition change converged and no increasing trend was reflected. The impact assessment of evapotranspiration was conducted by comparing the observed data with the computed results based on three cases supposition scenarios of meteorological data (temperature, global radiation and wind speed) using the FAO Penman-Monteith method. The results showed that the runoff was reduced by about 50% compared with the present hydrologic condition when each SRES and periods were compared. If there was no land use change, the runoff would decline further to about 3$\sim$5%.

• Journal of Life Science
• /
• v.20 no.7
• /
• pp.1012-1018
• /
• 2010

The aim of this study was to determine whether Alzheimer's amyloid precursor protein (APP) is dysregulated in adipose tissues of C57BL/6 male mice by high-fat diet (HFD) induced obesity, aging, or streptozotocin (STZ)-induced diabetes. APP mRNA expression was examined by quantitative real-time PCR (QPCR) in subcutaneous (SAT) and epididymal adipose tissues (EAT) from mice in 8 different condition groups. By combining conditions of age (16 weeks/26 weeks of age), diet (normal diet (ND)/high-fat diet), and induction of diabetes (non-diabetic/diabetic), 88 mice were divided into 8 different groups. QPCR demonstrated that APP expression in SAT was significantly increased by about two-fold in HFD-induced obese mice compared to both 16 week-old and 26 week-old mice in the ND group (16 weeks p=0.001; 26 weeks p<0.0001), but no changes in EAT was found. Particular effects of aging on APP gene expression were not observed in either adipose tissue depots. Significantly decreased APP expression was found in SAT in STZ-induced diabetic mice fed on ND or HFD at 16 weeks of age (ND p<0.05; HFD p<0.01). Linear regression analysis demonstrated that APP expression levels correlated with body weight in both the non-diabetic group (R=0.657, p<0.0001, n=39) and the diabetic group (R=0.508, p=<0.0001, n=49), but did not correlate with plasma glucose levels, which suggests that decreased APP expression in STZ-induced diabetic mice is most likely due to weight loss rather than hyperglycemia. These data confirm APP dysregulation by weight changes in humans and suggest a possible role linking midlife obesity with the later development of amyloidogenesis in the brain of older patients with Alzheimer's disease.

• Korean Journal of Medicinal Crop Science
• /
• v.2 no.1
• /
• pp.7-13
• /
• 1994

This study was conducted to investigate the relationships between yearly variations of climatic factors and yearly variations of productivity in Alisma plantago L. In addition, correlation coefficients among yield and yield components were estimated. The data of yield and yield components were collected from the Statistical Year Book of Seungju province, Reserach Report of Seungju Extension Station of Rural Development Administration, and farmers for 10 years from 1983 to 1992. The meteorological data gathered at the Seungju Weather Station for the same period were used to find out the relationships between climatic factors and productivity. Yearly variation of the amount of precipitation in October and the minimum temperature in November were large with coefficients of variation(C.V.) of 106.44, 144.08%, respectively, but the variation of the average temperature, maximum temperature, minimum temperature from July to September were relatively small. Fresh weight and dry weight of roots vary greatly with C. V. of 30.62, 31.85%, respectivly. Plant height and stem length show more or less small C. V. of 5.51, 6. 26%, respectively and leaf width, leaf length, number of stems and root diameter show still less variation. Correlation coefficients between maximum temperature in November and plant height, stem diamter, number of stems, root diamter and dry weight of roots are positively significant at the 5% level. There are high signficant positive correlations observed, between yield and yield components. The maximum temperature would be used as a predictive variable for the estimation of dry weight of roots and number of stems. Simple linear regression equations by the least square method are estimated for number of stems $(Y_1)$ and the maximum temperature in November(X) as $Y_1=4.7114+0.5333\;X\;(R^2=0.4410)$, and for dry weight of roots$(Y_2)$ and the maximum temperature in November(X) as $Y_2=55.0405+14.3233\;X\;(R^2=0.4511)$

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.3
• /
• pp.41-48
• /
• 1965

This study was aimed at knowing the magnitude of year variation in rice heading dates under the different seasonal cultures, and to estimate the heading date in advance. Using six rice varieties such as Kwansan, Suwon＃82, Suwon ＃144, Norin＃17, Yukoo＃132 and Paltal, the early, ordinary and late seasonal cultures had been carried out at Paddy Crop Division, Crop Experiment Station at Suwon for the six-year period 1959 to 1964. In addition the data of the standard rice cultures at the Provincial Offices of Rural Development for the 12-year period 1953 to 1954, were analyzed for the purpose of clarifying a relationship between variation of rice heading dates and some of meteorological data related to the locations and years. The results of this study are as follows: 1. Year variation of rice heading dates was as high as 14 to 21 days in the early seasonal culture and 7 to 14 days in the ordinary seasonal culture, while as low as one to seven days in the late seasonal culture which was the lowest among three cultures. The magnitude of variation depended greatly on variety, cultural season and location. 2. It was found out that there was a close negative correlation between the accumulated average air temperature for 40 days from 31 days after seeding and number of days to heading in the early seasonal culture. Accordingly, it was considered possible to predict the rice heading date through calculation of the accumulated average air temperature for the above period and then the linear regression(Y=a+bx). On the other hand, an estimation of the heading date in the late seasonal culture requires for the further studies. In the ordinary seasonal culture, no significant correlation between the accumulated average air temperature and number of days to heading was obtained in the six-year experiments conducted at Suwon. There was a varietal difference in relationship between the accumulated average air temperature for 70 days from seeding and number of days to heading in the standard cultures at the provincial offices of rural development. Some of varieties showed a significant correlation between two factors while the others didn't show any significant correlation. However, there was no regional difference in this relationship.

• Korean Journal of Environmental Biology
• /
• v.25 no.2
• /
• pp.168-177
• /
• 2007

By using DEM and digital actual vegetation map with MGE GIS software program, topographic features (altitude, slope, latitude, etc.) quantitatively were analysed and their data integrated as the index of climatic conditions (WI, CI, air temperature, etc.) in South Korea. Warmth Index (WI) decreases $5.27^{\circ}C{\cdot}month$ with latitudinal $1^{\circ} degree, and $3.41^{\circ}C{\cdot}month$ with attitudinal 100 m increase. The relationship between CI and WI values is expressed as a linear regression, $WI=116.01+0.96{\times}CI,\;R^2=0.996$. The distributional peaks of different plant communities along Warmth Index gradient showed the sequence of Abies nephrolepis, Taxus cuspidata, Abies koreana, Quercus mongolica, Carpinus laxiflora, Q. dentata, C. tschonoskii, Q. serrate, Pinus densiflora, Q. aliena, Q. variabilis, Q. acutissima, P. thunbergii, Q. acute, Castanopsis cuspidata var. sieboldii, Camellia japonica, Machilus thunbergii community from lower to higher values. The Quercus mongolica forest occurred frequently on E-NW and SE slope aspect within WI $70{\sim}80^{\circ}C{\cdot}month$ optimal range at mesic sites, NW and SE slope than xeric sites S and SW slope. The Q. serrata forest showed the most distributional frequency in NW and W slope aspect within WI $90{\sim}100^{\circ}C{\cdot}month$ range, Q. variabilis and Q. acutissima forest showed the high frequency of distribution in SE slope in WI $95{\sim}100^{\circ}C{\cdot}month$ range. By the slope gradient analysis, five groups were found: 1. Abies nephrolepis, Machilus thunbergii, 2. Taxus cuspidata, Abies koreana, Quercus mongolica, Q. dentata, Q. serrata, Q. variabilis, Castanopsis cuspidata var. sieboldii 3. Pinus densiflora, Q. aliena, Q. acutissima, P. thunbergii, Q. acuta 4. Carpinus laxiflora, Camellia japonica 5. C. tschonoskii from steep slope to gentle slope sequence.