• The Journal of Korean Society for Radiation Therapy
• /
• v.18 no.1
• /
• pp.1-5
• /
• 2006

Purpose: IMRT quality assurance(Q.A) is consist of the absolute dosimetry using ionization chamber and relative dosimetry using the film. We have in general used 0.015 cc ionization chamber, because small size and measure the point dose. But this ionization chamber is too small to give an accurate measurement value. In this study, we have examined the degree of calculated to measured dose difference in intensity modulated radiotherapy(IMRT) based on the observed/expected ratio using various kinds of ion chambers, which were used for absolute dosimetry. Materials and Methods: we peformed the 6 cases of IMRT sliding-window method for head and neck cases. Radiation was delivered by using a Clinac 21EX unit(Varian, USA) generating a 6 MV x-ray beam, which is equipped with an integrated multileaf collimator. The dose rate for IMRT treatment is set to 300 MU/min. The ion chamber was located 5cm below the surface of phantom giving 100cm as a source-axis distance(SAD). The various types of ion chambers were used including 0.015cc(pin point type 31014, PTW. Germany), 0.125 cc(micro type 31002, PTW, Germany) and 0.6 cc(famer type 30002, PTW, Germany). The measurement point was carefully chosen to be located at low-gradient area. Results: The experimental results show that the average differences between plan value and measured value are ${\pm}0.91%$ for 0.015 cc pin point chamber, ${\pm}0.52%$ for 0.125 cc micro type chamber and ${\pm}0.76%$ for farmer type 0.6cc chamber. The 0.125 cc micro type chamber is appropriate size for dose measure in IMRT. Conclusion: IMRT Q.A is the important procedure. Based on the various types of ion chamber measurements, we have demonstrated that the dose discrepancy between calculated dose distribution and measured dose distribution for IMRT plans is dependent on the size of ion chambers. The reason is small size ionization chamber have the high signal-to-noise ratio and big size ionization chamber is not located accurate measurement point. Therefore our results suggest the 0.125 cc farmer type chamber is appropriate size for dose measure in IMRT.

• The Journal of Korean Society for Radiation Therapy
• /
• v.22 no.2
• /
• pp.135-144
• /
• 2010

Purpose: The purpose of this study is that through production of phantom for respiration gated radiotherapy, assessing appropriacy of exposure dose for the therapy using RPM (Real-time Position Management). Materials and Methods: We located measurement object on the phantom for respiration gated radiotherapy made of 2 linear actuator, acrylic panel, stanchion, iron plate ets. to drive (up, down, front, back). Using 4D CT scan, we analyzed patient's respiration and reproduced the movement by computer. On the phantom, we located a 2D-Array (PTW) and an White water phantom (4.5 cm) and used DMLC (interval 2 cm) in the field size $10{\times}10\;cm$, then exposed 21EX X-ray 100 MU, in the case of phantom was (1) static (2) moving (3) gated using RPM respectively gantry $0^{\circ}$ and $90^{\circ}$ We measured with a 0.125 CC ionization chamber (PTW) on the phantom (7.5 cm) in the same condition. Results: Ionization chamber: There were within 0.3% of error with gating respiration and approximately 2% of error without gating in the same condition. 2D-Array: Gantry $90^{\circ}$, field size $10{\times}10\;cm$, using DMLC. There were within 3% of error with gating respiration and approximately 16% of error without gating. Conclusion: The phantom for respiration gated radiotherapy makes plans considering patient's movement, quantitative analysis of exposure dose and proper assessment therapy for IMRT patients using RPM possible.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.11 no.2
• /
• pp.52-60
• /
• 2009

This study was conducted to quantify the soil respiratory $CO_2$ emission (SR) in an apple orchard and to determine its relationship with key environmental factors such as air temperature, soil temperature and soil moisture content. Experiment was made over the period from 23 April 2007 to 31 March 2008 in 'Fuji' apple orchard of National Institute of Horticultural and Herbal Science in Suwon, Gyeonggi-do, Korea. The SR was measured by using the automatic opening/closing chamber system based on a closed method. Diurnal variations in SR showed an increase around 0700 hours with increasing soil temperature, its peak between 1400 and 1500 hours, and then a gradual decrease thereafter. Daily variations in SR depended largely on soil and air temperatures over the year, ranging from 0.8 to 13.7 g $CO_2$ $m^{-2}d^{-1}$. During the rainy spell in summer (July$\sim$Autumn) with higher temperature and more precipitation, the SR was lower than that in the spring (May$\sim$June) with moderate temperature. The SR showed a significant exponential relationship with soil temperature ($r^2=0.800$) and air temperature ($r^2=0.805$), but not with soil moisture content ($r^2=0.160$). The $Q_{10}$ values of SR with annual soil temperature and air temperature were 2.0 and 1.9, respectively. The annually integrated SR was 19.6 ton $CO_2$ $ha^{-1}$.

• Applied Biological Chemistry
• /
• v.19 no.4
• /
• pp.202-218
• /
• 1976

In this experiment American Summer Pairman apple was selected as test fruit in order to study the effect of sub-atmospheric pressure storage in the apple. keeping a certain pressure condition, a new sub-atmospheric pressure system was designed and constructed in which fruits were stored at $25^{\circ}C$ under two different atmospheric pressure conditions such as Normal Atmospheric Pressure (NAP) and Sub-Atmospheric Pressure (SAP). Moreover, they were divided into plots of 5% and 0% of $CO_2$, on the basis of gas composition. Under these conditions, the amount of respiration and ethylene evolution, and the changes of intercellular gas composition and organic components were investigated throughout the storage. The results obtained are as follows: (1) The intercellular gas was exhausted so rapidly by the SAP treatment that the gas equilibrium in the tissues reached within 5 minutes. (2) The amount of respiration was found to be higher in plots of NAP than SAP, and under the conditions, controlling $CO_2$ content, plots of $CO_2$ 5% were lower in the amount of respiration than $CO_2$ 0%. The climateric rise was revealed more slowly in plots of the SAP than NAP. These results indicate that the SAP treatment was an efficient method for controlling the respiration of fruits. Furthermore, these results were also realized with the results of the respiratory quotient (R.Q) and intercellular gas composition. (3) Evolution of ethylene, the ripening hormone in plant, was shown the similar tendency to the climacteric pattern of respiration; at the stage of climacteric maximum, the maximun amount of ethylene was found earlier in plots of NAP than SAP, and post climacteric stage was prolonged in the plots of the SAP compared to those of the NAP. The ethylene concentration in tissue appeared lower in plots of the SAP than NAP, which might suggest that the SAP treatment was caused to restriction of ethylene evolution. (4) Effects of the SAP treatment mentioned hitherto were proved also with the test of the external appearance such as changes of color and freshness, firmness, rotting and weight loss. (5) In the investigation of organic components, vitamin C and organic acids varied less in plots of SAP than NAP. Specially, it was remarkable that the loss of malic acid was least decreased by the SAP treatment. These effects of the SAP treatment were distinctive in the changes of the ratios of malic and citric acid to total acid, and the ratios of free sugar to free acid.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.3
• /
• pp.448-462
• /
• 2020

Dietary nutrition is a critical lifestyle factor that can reduce the risk of future cognitive impairments caused by dementia. Accumulating evidence suggests that dietary supplementation with Sulforaphane may help the prevention of cognitive impairments and dementia. Thus, Sulforaphane-enriched broccoli extract would hold promise to improve cognitive impairments of dementia patients. Here, we have used broccoli extracts, prepared from broccoli cultivated in Magma Seawater, to test if the broccoli extracts can be dietary supplement to improve cognitive impairments. Magma Seawater originated from Jeju Island, Korea is unique in terms of containing high concentrations of usable minerals (Zinc, Vanadium and Germanium etc.). Broccoli, grown in Magma Seawater, would contain Sulforaphane and the extra amount of usable minerals. The chemical compositions of the broccoli extracts were analyzed using LC-Q-orbitrap to detect Sulforaphane and Glucoraphanin. Analysis method based on HPLC was developed for measurement of sulforaphane levels in the broccoli extracts. We have tested if the broccoli extracts have anti-apoptotic and anti-inflammatory effects on neuron-like SH-SY5Y cells. In addition, we examined if the broccoli extracts are able to upregulate expression of synaptic plasticity-associated proteins (BDNF and phospho-CREB) and to inhibit acetylcholine esterase (AchE) activity. We have shown that the broccoli extracts inhibited the apoptotic pathway and inflammatory responses. Finally, we present evidence showing that AchE activity was inhibited by the broccoli extracts, but expression of BDNF and phospho-CREB was upregulated. Taken together, these findings suggest that the broccoli extracts from Magma Seawater-grown broccoli would be a good source of dietary nutrition to improve cognitive impairments in the future.

• Clinical and Experimental Reproductive Medicine
• /
• v.26 no.3
• /
• pp.457-465
• /
• 1999

Objective: The presence of Y chromosome in patients with gonadal dysgenesis is related to the risk of gonadoblastoma. Since the patients with abnormal sexual differentiation may have cryptic Y mosaicism, it is important to detect the presence of Y material in these patients. But sometimes it is difficult to detect Y material only with karyotyping. This study was performed to evaluate the usefulness of the SRY gene screening in blood and gonad by using PCR in detecting the presence of Y material and possible tissue mosaicism in patients with gonadal dysgenesis as Turner syndrome and 46,XY pure gonadal dysgenesis (PGD, Swyer syndrome). Method: In 26 patients with gonadal dysgenesis, we screened for Y material by using PCR for SRY gene in peripheral leukocytes and in gonadal tissues of some patients. They were 22 cases of Turner syndrome (7 45,XO, 2 46,Xi(Xq), 3 45,XO/46,XX, 5 45,XO/46,Xi(Xq), 1 45, XO/46,XY, 1 45,XO/46,Xi(Yq), 1 45,XO/47,XYY, 1 46,XX,del(X)(q24) and 1 46,X,+mar) and 4 cases of 46,XY pure gonadal dysgenesis. PCR for SRY gene in the gonadal tissue was performed in 5 Turner syndrome and 2 PGD to determine the cryptic Y mosaicism between blood and gonad. Results: By using PCR analysis for SRY, Y chromosome material was detected in the blood of 4 of 22 Turner syndrome patients (45,XO/46,Xi(Xq), 45,XO/46,Xi(Yq), 45,XO/46,XY, and 45, XO/47,XYY), 3 of 4 46,XY pure gonadal dysgenesis. Discrepancy between karyotyping and blood PCR for SRY was noted in 1 Turner syndrome (45,XO/46,Xi(Xq)) and 1 PGD. Laparoscopic gonadectomy was performed in Y containing or SRY positive cases. In addition, PCR analysis for SRY in the gonads of 5 Turner syndrome and 2 PGD showed discrepancy between blood and gonad or between both gonads in 3 Turner syndrome (45,XO/46,Xi(Xq), 45,XO/46,Xi(Y q), 45,XO/46,XY) and 2 PGD patients. Conclusion: In gonadal dysgenesis, PCR analysis for SRY gene is useful to detect the cryptic Y mosaicism that is sometimes undetected by karyotyping. And since there may be tissue mosaicism, it is necessary to evaluate Y mosaicism in various tissues even in the case without Y chromosome on karyotyping.

• Journal of Life Science
• /
• v.17 no.5 s.85
• /
• pp.699-705
• /
• 2007

The present study was conducted to investigate the genetic characteristic and to establish the parentage verification system of the Korean native horse(KNH). A total number of 192 horses from six horse breeds including the KNH were genotyped using 17 microsatellite loci. This method consisted of multiplexing PCR procedure. The number of alleles per locus varied from 5 to 10 with a mean value of 7.35 in KNH. The expected heterozygosity and observed heterozygosity were ranged from 0.387 to 0.841(mean 0.702) and from 0.429 to 0.905(mean 0.703), respectively. The total exclusion probability of 17 microsatellite loci was 0.9999. Of the 17 markers, AHT4, AHT5, CA425, HMS2, HMS3, HTG10, LEX3 and VHL20 marker have relatively high PIC value(>0.7). This study found that there were specific alleles, P allele at AHT5, Q allele and R allele at ASB23, H allele at CA425, S allele at HMS3, J allele at HTG10 and J allele at LEX3 marker in KNH when compared with other horse populations. Also, the results showed two distinct clusters: the Korean native horse cluster(Korean native horse, Mongolian horse), and the European cluster(Jeju racing horse, Thoroughbred horse). These results present basic information for detecting the genetic markers of the KNH, and has high potential for parentage verification and individual identification of the KNH.

• Journal of the Korean Geotechnical Society
• /
• v.35 no.10
• /
• pp.47-66
• /
• 2019

A parametric numerical analysis according to diameter, length, and N values of soil was conducted for the PHC pile socketed into weathered rock through sandy soil layers. In the numerical analysis, the Mohr-Coulomb model was applied to PHC pile and soils, and the contacted phases among the pile-soil-cement paste were modeled as interfaces with a virtual thickness. The parametric numerical analyses for 10 kinds of pile diameters were executed to obtain the load-settlement relationship and the axial load distribution according to N-values. The load-settlement curves were obtained for each load such as total load, total skin friction, skin friction of the sandy soil layer, skin friction of the weathered rock layer and end bearing resistance of the weathered rock. As a result of analysis of various load levels from the load-settlement curves, the settlements corresponding to the inflection point of each curve were appeared as about 5~7% of each pile diameter and were estimated conservatively as 5% of each pile diameter. The load at the inflection point was defined as the mobilized bearing capacity ($Q_m$) and it was used in analyses of pile bearing capacity. And SRF was appeared above average 70%, irrespective of diameter, embedment length of pile and N value of sandy soil layer. Also, skin frictional resistance of sandy soil layers was evaluated above average 80% of total skin frictional resistance. These results can be used in calculating the bearing capacity of prebored PHC pile, and also be utilized in developing the bearing capacity prediction method and chart for the prebored PHC pile socketed into weathered rock through sandy soil layers.

• Journal of vocational education research
• /
• v.37 no.2
• /
• pp.39-75
• /
• 2018

The purpose of this study is to verify the general characteristics in the previous studies and the magnitude of the correlation between the learner's satisfaction and the academic achievement in the education and training program. To do this, we searched relevant literature from 2000 to 2016, and conducted a systematic review of the literature on the final 31 studies through the selection criteria and quality evaluation. Among them, 27 meta-analysis of the literature was conducted. The finding of the study were as follows. First, a total of 31 studies were conducted from 2000 to 2016, and more than half of them(16) were conducted for the last 4 years(2009~2012). In terms of education and training students, there are 18 college students, 9 workers, and 4 elementary students in order of study. In terms of methods, 15 collective education, 14 distance education, 2 blended education. In terms of learner's participation, 22 the general participation, 9 the active participation. Second, as a result of the meta-analysis, the magnitude of the correlation between satisfaction and achievement was moderate(ZCOR=.297, 95%: CI .210~.383). Third, as a result of verifying the difference in the magnitude of the correlation effect between satisfaction and achievement according to the characteristics of the education and training program, there was no difference between the groups in the student object and education method, but there was a difference in the magnitude of the correlation effect depending on the participant type(Q=15.40, df=1, p<.0001). The active participation showed a correlation effect size larger(ZCOR=.588, 95%: CI .422~.754). The effect size of the general participation was lower than the median(ZCOR=.211, 95%: CI .12 ~.300).

• Journal of Korean Society of Forest Science
• /
• v.108 no.2
• /
• pp.147-167
• /
• 2019

This study was conducted to analyze forest vegetation structure in the Marugeum (Ridge) area of Gitdaebaegibong to Jukryeong, Baekdudaegan. Data were collected in 298 quadrates through a Braun-Blanquet vegetation survey from April, 2018 to October, 2018. Forest vegetation was classified into 13 vegetation units. A Quercus mongolica community was divided into Morus bombycis, Filipendula glaberrima, Fraxinus sieboldiana, Prunus maackii unit and Q. mongolica typical unit. The M. bombycis unit was further classified into a Deutzia glabrata group and M. bombycis typical group. The F. glaberrima unit was subdivided into a Veratrum oxysepalum group, Arundinella hirta group, and F. glaberrima typical group. The F. sieboldiana unit was divided into a Pinus densiflora group, Larix kaempferi group, and F. sieboliana typical group. The relationship between vegetation units and environmental factors was studied through coincidence analysis and CCA. The F. glaberrima unit (VU 6~8) was distributed by elevation above 1,200 m and other vegetation units were distributed below 1,200 m. Results of the CCA analysis showed that the F. glaberrima unit distribution is positively correlated with elevation. As a result of species diversity, the F. glaberrima unit was higher than other vegetation units. A similarity index analysis revealed that the F. sieboldiana unit (VU 9~11) was relatively homogeneous, and the M. bombycis unit (VU 1~5) and A. girta group (VU 7) were relatively heterogeneous. A detrended correspondence analysis determined that the distance between the statistical axes of the M. bombycis and F. glaberrima units was the greatest, which is consistent with the analysis of the similarity index. As a result of interspecific correlation of major woody plants, hydrophilic species were positively correlated, and a negative correlation was found between Q. mongolica and intolerant species such as P. densiflora and L. kaempferi.