• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6385-6390
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• 2012

A number of studies have been conducted to explore the association of XRCC1 polymorphisms with thyroid cancer risk, but the results have been inconsistent. Thus we performed the present meta-analysis to clarify this issue based on all of the evidence available to date. Relevant studies were retrieved by searching PubMed and statistical analysis conducted using Stata software. Nine studies were included in this meta-analysis (1,620 cases and 3,557 controls). There were 6 studies (932 cases and 2,270 controls) of the Arg194Trp polymorphism, 7 studies (1432 cases and 3356 controls) of the Arg280His polymorphism and 9 studies (1,620 cases and 3,557 controls) for the Arg399Gln polymorphism. No association of XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphism with thyroid cancer risk was observed in the overall analysis. However, subgroup analysis revealed: 1) an elevated risk in aa vs AA analysis (OR=2.03, 95%CI= 1.24-3.31) and recessive genetic model analysis (OR=1.93, 95%CI= 1.20-3.08) in the larger sample size trials for XRCC1 Arg194Trp polymorphism; 2) a decreased thyroid cancer risk on subgroup analysis based on ethnicity in Aa vs AA analysis (OR=0.84, 95%CI= 0.72-0.98) and in a dominant genetic model (OR=0.84, 95%CI= 0.72-0.97) in Caucasian populations for the XRCC1 Arg399Gln polymorphism; 3) a decreased thyroid cancer risk on subgroup analysis based on design type in Aa vs AA analysis (OR=0.72, 95% CI= 0.54-0.97) among the PCC trials for the Arg399Gln polymorphism. Our results suggest that the XRCC1 Arg399Gln polymorphism may be associated with decreased thyroid cancer risk among Caucasians and XRCC1 Arg194Trp may be associated with a tendency for increased thyroid cancer risk in the two larger sample size trials.

• Journal of The Korean Association For Science Education
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• v.35 no.2
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• pp.333-342
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• 2015

This study analyzes the verbal interaction patterns used in a social network activity analysis that appeared in a science inquiry activity of 31 small groups of science-gifted students consisting of 5 members each. The results of this study are as follows: The interaction patterns showed eight types. The most prevalent interaction pattern, type 1, is triangle-shaped, interacting with 3 members out of 5 without a central member. Type 2 is wye form, interacting with 4 members and with one alienated member. Type 3 is diamond-shaped, interacting with 4 members. Type 4 is ray form, interacting with 5 around a central member. Type 5 has an alienated member and interacts with 4 members around the central member. Type 6 is triangle-branched, 4 members linked to the central member. Type 7 is wye form linked all around the central member. Type 8 is wye form with a more complex link than type 7. These can be classified in two. One is the participation-type where the rest of the 4 members are linked to the central member. The other is the alienation-type where a member/members is/are alienated without a central member. The participation-type appeared in 9 groups (29%), type 4, type 6, type 7, and type 8. The alienation-type showed in 22 groups (71%), type 1, type 2, type 3, and type 5. On the basis of this study, we propose that the best number of members in a group is three. It helps prevent a free-riding effect or isolation of members. Also, we deem it more fruitful if there is a member playing a central role in a group.

• Radiation Oncology Journal
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• v.2 no.2
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• pp.271-280
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• 1984

The peripheral dose, defined as the dose outside therapeutic photon fields, which is responsible for the functional damage of the critical organs, fetus, and radiation. induced carcinogenesis, has been investigated for $^{60}Co\;\gamma$ ray and 10 MV Xray. It was measured by silicon diode controlled by semiautomated water phantom without any shielding or with lead plate of HVL thickness put horizontally or vertically to shield stray radiations. Authors could obtain following results. 1. The peripheral dose was larger than $0.7\%$ of central axis maximum dose even at 20cm distance from field margin. That is clinically significant, so it should be reduced. 2. Even for square fields of 10 MV Xray, radial peripheral dose distribution did not coincide with transverse distribution, because of the position of collimator jaws. 3. Between surface and $d_m$, the peripheral dose distributions show a pattern of the dose distribution of electron beams and the maximum doss was approximately proportional to the length of a side of square field. 4. The peripheral doses depended on radiation quality, field size, distance from field margin and depth in water. Distance from field margin was the most important factor. 5. Except for near surface, the peripheral dose from phantom was approximately equal to that from therapy unit. 6. To reduce the surface dose outside fields, therapist should shield stray radiations from therapy unit by lead plate of at least one HVL for 10 MV X-ray and by bolus equivalent to tissue of 0.5cm thickness for $^{60}Co$. 7. To reduce the dose at depth deeper than $d_m$, it is desirable to shield stray radiations from therapy unit by lead.

• Advances in pediatric surgery
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• v.5 no.2
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• pp.146-151
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• 1999

Neurocristopathy originates from aberrant development of the neural crest by genetic abnormality. Dysgenetic or neoplastic neurocristopathy mayor may not combine at one or more organs. Congenital central hypoventilation syndrome (Ondine's curse) is characterized by the respiratory depression during sleep, although showing normal ventilation while awake, because the baby does not responde to hypercapnea or hypoxia. One newborn girl, full-term, 3,020 g of birth weight with neurocristopathy is reported. It showed poor respiration at birth, and temporary Improvement with oxygen and respiratory stimulations. Abdomen was distended. Abdominal x-ray revealed small bowel obstruction and calcified opacity at the right lower quadrant. Because transitional zone was noticed at the distal jejunum during laparotomy, jejunostomy was performed. Several times trial of extubation have failed becaused of the repeated apneas. Brain sonography and echocardiogram were normal. The patient died of sepsis at 37 days of age. Para-aortic ganglioneuroblastoma was found at autopsy. In this case, congenital central hypoventilation syndrome, Hirschsprung's disease and congenital ganglioneuroblastoma are combined as a neurocristopathy.

• Journal of Pharmaceutical Investigation
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• v.38 no.1
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• pp.9-14
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• 2008

Cation exchange resin complex of amlodipine free base has been investigated to improve the stability and dissolution profile. The complex was prepared by reacting amlodipine solution with activated cation exchange resin, and amlodipine content in the complex was 31.6% calculated by HPLC determination. Its product was not physical mixture but the complex formed by ionic bond, which was identified by microscope system, differential scanning calorimetry and X-ray diffractometry. Each tablet containing amlodipine free base(I) and its complex(II) was prepared for the accelerated stability test ($40^{\circ}C$, 75%RH) and dissolution test in the pH 1.2 buffer solution and purified water media. Dissolution patterns of formulation II in both media were similar to those of $Norvasc^{(R)}$ tablet, but the pattern of formulation I in purified water was different. After 6 months storage under stability test, amlodipine content of formulation I, II and $Norvasc^{(R)}$ tablet were $99.3{\pm}1.2%,\;98.9{\pm}1.4%\;and\;83.9{\pm}3.4%$, respectively. While amlodipine free base was unstable at the condition, its complex was not only significantly stable, but also similar in the dissolution pattern. These results suggest the usefulness of complex as a stable carrier for amlodipine free base.

• Journal of the Korean Vacuum Society
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• v.2 no.2
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• pp.181-187
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• 1993

We have studied the anodic oxidation of silicon in the anisotropic etchant of EPW(Ethylenediamine, Pyrocatechol and Water) solution using the cyclic polarization technique. The samples have been characterized by means of X-ray photoelectron spectroscopy(XPS) and secondary ion mass spectrometry (SIMS). The results of cyclic polarization experiments show that the anodic oxides formed on p- and n-type silicon wafers break down at the same potential while breakdown does not occur up to open circuit potential in the case of $p^+$-Si. Strong etch-resistance of $p^+$-XPS. SIMS depth profiles suggest that the critical concentration of boron for etch-stop to occur appears to be much higher than what is widely believed.

• Progress in Medical Physics
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• v.22 no.3
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• pp.131-139
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• 2011

A method to get a size of the radiation isocenter of linear accelerators using star-shot images was presented and a computer program was developed to automate the method. Accuracy of the method was verified. The developed program was used to measure sizes of the radiation isocenters for a Clinac 21EX (Varian, USA) using data of quality assurance (QA) performed from June 2008 to December 2010. To calculated the size of radiation isocenter, positions of two points on each central ray of the star-shot image were found and the equation of the central ray was determined using the positions of two points. Using the equations of central rays the radius of the minimum circle intersecting all the central rays, which is one half of the size of radiation isocenter, was calculated. The program measured x-intercepts and y-intercepts of the central rays within errors of 0.084 mm and sizes of radiation isocenters within 0.053 mm. All the errors were less than the spatial resolution of star-shot images 0.085 mm. The radiation isocenter sizes of Clinac 21EX were $0.33{\pm}0.27mm$, $0.71{\pm}0.36mm$, $0.50{\pm}0.16mm$ for collimator, gantry and couch respectively. During the measurement period all the measured sizes were less than 2.0 mm and within tolerance. The developed program could calculate the size of radiation isocenters and it would be helpful to routine QA.

• Journal of radiological science and technology
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• v.45 no.4
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• pp.299-304
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• 2022

This study uses the 'S-align' function to present a reference value of the X-ray tube angle for the realization of an image similar to that of the chest PA image during chest AP radiography. This study targeted dummy phantom and used a 17"×17" DR image receptor. The irradiation conditions were 110 kVp, 160 mA, 50 ms, and the distance between the central X-ray and the image receptor was set to 180 cm and 110 cm, respectively. The end of the catheter was placed at the 11th thoracic height to indicate the nasogastric tube. In the case of lung apex length measurement, the mean value of measurement was 30.53±0.47 in PA. T 0°, TCA 5~25°, TCE 5~15° were 21.07±0.29, 27.60±0.21, 34.13±0.44, 39.86±0.31, 45.96±0.61 mm, 54.13±0.37 mm, 16.16±0.46 mm, 9.81±0.35 mm, 2.75±0.30 mm, respectively. For the depth of the catheter end, the average value measured at PA was 6.70±0.31 mm. T 0°, TCA 5~25°, TCE 5~15° were 15.72±0.38 mm, 24.10±0.50 mm, 29.24±0.86 mm, 34.35±0.35 mm, 41.06±1.08 mm, 48.07±0.38 mm, 12.85±0.25 mm, 7.92±0.36 mm, 3.01±0.39 mm, respectively. The length of the lung apex was similar to that of chest PA when the angle of incidence was adjusted from 5° to 10° in the leg direction, and the depth of the catheter tip was most similar when the X-ray tube angle was incident at 10° in the head direction. Therefore, To change the X-ray tube angle according to the purpose of the examination during the chest AP radiography using 'S-align' function is considered necessary.

• Journal of Astronomy and Space Sciences
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• v.18 no.1
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• pp.1-6
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• 2001

In this paper we investigate the properties of advection-dominated accretion flows (ADAFs) in case that outflows carry away infalling matter with its angular momentum and energy. Positive Bernoulli number in ADAFs allow a fraction of the gas to be expelled in a form of outflows. The ADAFs are also unstable to convection. We present self-similar solutions for advection-dominated accretion flows in the presence of outflows from the accretion flows(ADIOS). The axisymmetric flow is treated in variables integrated over polar sections and the effects of outflows on the accretion flow are parameterized for possible configurations compatible with the one dimensional self-similar ADAF solution. We explicitly derive self-similar solutions of ADAFs in the presence of outflows and show that the strong outflows in the accretion flows result in a flatter density profile, which is similar to that of the convection-dominated accretion flows(CDAFs) in which convection transports the angular momentum inward and the energy outward. There two different versions of the ADAF model should show similar behaviors in X-ray spectrum to some extent. Even though the two models may show similar behaviors, they should be distinguishable due to different physical properties. We suggest that for a central object of which mass is known these two different accretion flow should have different X-ray flux value due to deficient matter in the wind model.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.77.3-78
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• 2015

It is known that the galaxy evolution by direct interaction between galaxies is most active in a galaxy group. As a result, the satellite galaxies are closely related to their central galaxy in properties such as morphology, color and star formation rate (so-called 'galactic conformity'). However, it is not clear yet whether such conformity between galaxies is found in a galaxy cluster. Recently, Lee et al. (2014) have found a measurable correlation between the colors of bright galaxies and the mean colors of their faint companions in a cluster WHL J085910.0+294957 at z = 0.3, using the photometrically-selected cluster members. They suggest that such correlation may be the vestige of infallen groups in the cluster as one possibility. In order to confirm the small-scale conformity in galaxy clusters with higher reliability, we study the Virgo cluster using the Extended Virgo Cluster Catalog (EVCC). The cluster members are selected spectroscopically unlike in WHL J085910.0+294957. We examine the galactic conformity in two distinct areas of the Virgo cluster: the inner X-ray emission region and its outer region. We find a marginal conformity in color (> $2{\sigma}$ significance to bootstrap uncertainty) in the outer region, while no meaningful signal of small-scale conformity is detected in the X-ray emission region. We discuss the implication of this result, focusing on cluster mass assembly and cluster environmental effects on galaxy evolution.