• Radiation Oncology Journal
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• v.10 no.1
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• pp.27-34
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• 1992

Cis-Platinum (DDP) was utilized as a radiosensitizer in a pilot study for stage III and IV squamous cell carcinoma between 1984-1987, and DDP 20 $mg/M^2$/day was administered for 4 days at 3 week interval with concurrent radiotherapy. This study consisted of three phases: cytoreduction phase, eradicative treatment phase and adjuvant phase. Total 59 patients were subjected to evaluate a tumor response and its toxicity. During the eradicative phase,27 patients underwent surgery (group I ), 29 patients were treated with radiotherapy only (group II) and 3 patients did not complete the second phase of therapy. At the cytoreduction phase, $95\%$ response rate with complete response (CR) $47.5\%$ and partial response (PR) $47.5\%$ was observed. Complete tumor clearance (CTC) rate following 2nd phase of therapy was $84\%$ (47/56) with 26/27($96\%$) in group I achieved CTC with surgery and 21/29 ($72\%$) patients In group II achieved CTC following 2nd phase. $67\%$ of primary lesions and $70\%$ of nodal diseases in group I showed no tumor in the surgical specimen. $34\%$ of patiets who achieved CTC at 2nd phase developed recurrence and median time to recur was 8 months. Actuarial disease free survival at 4 years was $59\%$ and $51\%$(24/27) of patients who achieved CTC at 2nd phase were alive without any evidence of disease at median follow-up 31 months (range, 10-48 months). There was no significant difference in overall and disease free survival between group I and II between CR and PR group following 1st Phase. Only significant Prognostic factor in this study was the complete tumor clearance following 2nd phase theapy. In general, toxicity was not excessive. Author concludes that this study confirmed the significant radiosensitizing effect of DDP with the acceptable toxicity and warrant the prospective study to determine optimum scheduling for DDP and radiotherapy which maximizes the therapeutic gain.

• Journal of the Korean earth science society
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• v.33 no.2
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• pp.148-161
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• 2012

The intensive observation (ProbeX-2010) with 6-hour launches of radiosonde was performed over Seoul metropolitan area (Dongducheon, Incheon Airport, and Yangpyeong) from 13 Aug. to 3 Sep. 2010. Five typical heavy rainfall patterns occurred consecutively which are squall line, stationary front, remote tropical cyclone (TC), tropical depression, and typhoon patterns. On 15 Aug. 03 KST, when squall line developed over Seoul metropolitan area, dry mid-level air was drawn over warm and moist low-level air, inducing strong convective instability. From 23 to 26 Aug and from 27 to 29 Aug. Rainfall event occurred influenced by stationary front and remote TC, respectively. During the stationary frontal rainy period, thermal instability was dominant in the beginning stage, but dynamic instability became strong in the latter stage. Especially, heavy rainfall occurred on 25 Aug. when southerly low level jet formed over the Yellow Sea. During the rainy period by the remote TC, thermal and dynamic instability sustained together. Especially, heavy rainfall event occurred on 29 Aug. when the tropical air with high equivalent potential temperature (>345 K) occupied the deep low-middle level. On 27 Aug. and 2 Sep. tropical depression and typhoon Kompasu affected Seoul metropolitan area, respectively. During these events, dynamic instability was very strong.

• Journal of Oral Medicine and Pain
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• v.36 no.2
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• pp.131-137
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• 2011

Current Perception Threshold (CPT) using Neurometer($Neurometer^{(R)}$ CPT/C) is thought as one of easy and noninvasive QST(qunatitative sensory testing) tools for A${\beta}$, A${\delta}$ and C fibers within a relatively short time. However, conflicts about its reliability still exist. This study aimed to evaluate the reliability of CPTs evaluation and find a way to increase its reliability. Two examiners separately tested CPTs at each side of the mandibluar nerve areas for ten healthy male adults (average age of 22.4 years) three times with an intervals of a week during three weeks. Mean CPTs were compared between the right and left sides of the mandibular nerve area and between the three examinations on the each side. While CPTs at 2000 Hz(A${\beta}$ fiber) showed statistically significant side differences in all three examinations (p<0.05), significant side difference was found in only one examination at 250 Hz(A${\delta}$ fiber) and no difference at 5 Hz(C fiber). Comparing CPTs on the each side of the mandibular nerve area, all examinations at all sensory nerve fibers showed the least CPTs at the 1st examinations. CPTs at 250 Hz(A${\delta}$ fiber) and 5 Hz(C fiber) were significantly different between the first and the following examinations (p<0.05) and there was no significant difference between 2nd and 3rd examinations. The results of this study indicated that CPTs at 250 Hz(A${\delta}$ fiber) and 5 Hz(C fiber) are reliable but CPTs at 2000 Hz(A${\beta}$ fiber) is not appropriate for evaluation of side differences in the mandibular nerve area. In addition, it is suggested that repeated examination be helpful to increase reliability of the CPT evaluation.

• The korean journal of orthodontics
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• v.29 no.3 s.74
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• pp.361-374
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• 1999

Intraoral filled type of orthodontic appliance can cause reversible or irreversible damages such as gingivitis, periodontitis, enamel decalcification, dental caries, root resorption, and pulpal changes. Such adverse effects are brought by increase in dental plaque as well as oral flora. Such an increase causes gingival inflammation and enamel decalcification. The purpose of this study is to get klowledge on initial changes in dental plaque, gingivitis, and enamel decalcification after bonding fixed orthodontic appliances according to time flow, gender, and sides(right/left) of premolar region. For control group, 48 students of dental college, Yonsei university(26 males, 22 females) were chosen; for experimental group, 73 orthodontic patients(36 males, 37 females) who will be treated with fixed appliances were chosen. All the subjects had no systemic disease, juvenile periodontitis and all the females had passed their ,menarche. Tooth brushing instruction was given to all the subjects prior to the experiment. For control group, plaque index, gingival index, and decalcification index were measured twice at 3 weeks interval ; for experimental group, the same was done prior to, 3, 6, 9 weeks after bonding fixed appliances. The following results were obtained: 1. In plaque index 3 weeks after placement of appliances, and it showed gradual increase afterwards. 2. In gingival index3 weeks after placement of appliances, and afterwards it showed increase at a faster rate than plaque index. 3. Enamel decalcification began to show between 3 and 6 weeks after bonding fixed appliances. Decalcification index began to increase 6 weeks after appliance placement, but there was no statistical significance. 4. When the comparison was made between two sides of premolar region, the right side showed greater index in plaque and gingival index of experimental group.

• Neonatal Medicine
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• v.18 no.2
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• pp.240-247
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• 2011

Purpose: The rationale for skin surface cultures is that bacterial colonization precedes infection and, as a result, that identification of a potential pathogen is predictive of later systemic infection in preterm infants. We aimed to analyze results of surveillance surface cultures in extremely low birth weight (ELBW) infants and seek for effective ways of performing surveillance surface cultures. Methods: We analyzed the surveillance surface cultures of 113 ELBW infants over a 4-year period. Surveillance cultures were obtained routinely from five sites: axilla, external ear canal, nasopharynx, throat (or tracheal aspirate if intubated) and anus. Each surface culture obtained during the 13 days, prior to the date of the blood culture, was compared with the blood culture obtained when sepsis was suspected. The sensitivity, specificity and positive predictive value (PPV) of the surveillance cultures were calculated among 1894 blood-surface culture pairs by surface sites, recovered organisms and interval between surveillance samples and blood cultures. Results: The overall sensitivity, specificity and PPV of surface cultures were 45.9, 22.4 and 6.8%, respectively. The PPV was highest for the throat/tracheal cultures (11.0%) and lowest for the anal cultures (2.3%). As the time of culturing progressed toward the day of blood culturing, the sensitivity and specificity of the surface cultures significantly increased. Only axillary and throat/tracheal cultures were useful in predicting the microorganisms causing sepsis. Conclusion: Surface cultures could help to predict sepsis pathogens and infection surveillance in preterm infants could be continued with a reduced number of cultured sites focusing on the axilla and throat/trachea.

• Economic and Environmental Geology
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• v.44 no.1
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• pp.71-82
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• 2011

The unsaturated soil column tests were carried out for weathered gneiss soil and weathered granite soil in order to obtain the relationship between rainfall intensity and infiltration velocity of rainfall on the basis of different unit weight conditions of soil. In this study, volumetric water content and pore water pressure were measured using TDR sensors and tensiometers at constant time interval. For the column test, three different unit weights were used as in-situ condition, loose condition and dense condition, and rainfall intensities were selected as 20 mm/h and 50 mm/h. In 20 mm/h rainfall intensity condition, average rainfall infiltration velocities for both gneiss and weathered granite soils were obtained as $2.854{\times}10^{-3}$ cm/s ~ $1.297{\times}10^{-3}$ cm/s for different unit weight values and $2.734{\times}10^{-3}$ cm/s ~ $1.707{\times}10^{-3}$ cm/s, respectively. In 50 mm/h rainfall intensity condition, rainfall infiltration velocities were obtained as $4.509{\times}10^{-3}$ cm/s ~ $2.016{\times}10^{-3}$ cm/s and $4.265{\times}10^{-3}$ cm/s ~ $3.764{\times}10^{-3}$ cm/s respectively. The test results showed that the higher rainfall intensity and the lower unit weight of soil, the faster average infiltration velocity. In addition, the weathered granite soils had faster rainfall infiltration velocities than those of the weathered gneiss soils except for the looser unit weight conditions. This is due to the fact that the weathered granite soil had more homogeneous particle size, smaller unit weight condition and larger porosity.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.273-284
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• 2007

The spatial and temporal zooplankton dynamics were examined along ca. 100-km section of the middle to lower Seomjin River (without estuary dam in river mouth) and Youngsan River (with estuary dam in river mouth) systems during study periods (2004. Nov.${\sim}$2006. Aug.) based on a monthly sampling intervals. The spatial variation of zooplankton biomass at both river ecosystems was distinct. There was considerable longitudinal variation in total zooplankton abundance in Youngsan R. stretch. The increase in total zooplankton abundance were observed along the longitudinal stretch toward the estuary dam. In contrast, there were not statistically significant longitudinal differences in total zooplankton abundance in Seomjin R. stretch. In Youngsan R. stretch, average abundance of total zooplankton (average ranges: $199{\sim}817$ Ind. $L^{-1}$ at 3 sampling sites, n=20) were nearly $4{\sim}60$ fold higher than that of Seomjin R. stretch (average ranges: $12{\sim}43$ Ind. $L^{-1}$ at 4 sampling sites, n=20). Relative abundance of rotifers (over 80% of total zooplankton abundance) at the whole sampling sites in Youngsan R. stretch were Much higher than that of the Seomjin R. stretch. The most abundant rotifers were Polyarthra spp., Brachionus spp., Colurella spp., and Keratella spp. at the both river ecosystems. In Seomjin R. stretch, copepods carbon biomass sharply increased toward in river mouth (over 40% of total zooplankton carbon biomass). Average ranges of total zooplankton filtering rates for phytoplankton at both river ecosystems varied from 21.2 to 92.9 mL $L^{-1}\;D^{-1}$ in Youngsan R. stretch and from 2.1 to 2.6 mL $L^{-1}\;D^{-1}$ in Seomjin R. stretch. Considering the zooplankton filtering rates, zooplankton as grazers of phytoplankton in Youngsan R. stretch seemed to play the more important role in planktonic food web than that of the Seomjin R. stretch.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.106-110
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• 2016

In this study, a planting density-growth-harvest (PGH) chart was developed to easily read the growth and harvest factors such as crop growth rate, relative growth rate, shoot fresh weight, shoot dry weight, harvesting time, marketable rate, and marketable yield of common ice plant (Mesembryanthemum crystallinum L.). The plants were grown in a nutrient film technique (NFT) system in a closed-type plant factory using fluorescent lamps with three-band radiation under a light intensity of $140{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and a photoperiod of 12 h. Growth and yield were analyzed under four planting densities ($15{\times}10cm$, $15{\times}15cm$, $15{\times}20cm$, and $15{\times}25cm$). Shoot fresh and dry weights per plant increased at a higher planting density until reached an upper limit and yield per area was also same tendency. Crop growth rate, relative growth rate and lost time were described using quadratic equation. A linear relationship between shoot dry weight and fresh weights was observed. PGH chart was constructed based on the growth data and making equations. For instance, with within row spacing (= 20 cm) and fresh weight per plant at harvest (= 100 g), we can estimate all the growth and harvest factors of common ice plant. The planting density, crop growth rate, relative growth rate, lost time, shoot dry weight per plant, harvesting time, and yield were $33plants/m^2$, $20g{\cdot}m^{-2}{\cdot}d^{-1}$, $0.27g{\cdot}g^{-1}{\cdot}d^{-1}$, 22 days, 2.5 g/plant, 26 days after transplanting, and $3.2kg{\cdot}m^{-2}$, respectively. With this chart, we could easily obtain the growth factors such as planting density, crop growth rate, relative growth rate, lost time and the harvest factors such as shoot fresh and dry weights, harvesting time, marketable rate, and marketable yield with at least two parameters, for instance, planting distance and one of harvest factors of plant. PGH charts will be useful tools to estimate the growth and yield of crops and to practical design of a closed-type plant production system.

• Journal of Preventive Medicine and Public Health
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• v.49 no.2
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• pp.80-96
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• 2016

Recently, a series of lawsuits were filed in Korea claiming tort liability against tobacco companies. The Supreme Court has already issued decisions in some cases, while others are still pending. The primary issue in these cases is whether the epidemiological evidence submitted by the plaintiffs clearly proves the causal relationship between smoking and disease as required by civil law. Proving causation is difficult in tobacco lawsuits because factors other than smoking are involved in the development of a disease, and also because of the lapse of time between smoking and the manifestation of the disease. The Supreme Court (Supreme Court Decision, 2011Da22092, April 10, 2014) has imposed some limitations on using epidemiological evidence to prove causation in tobacco lawsuits filed by smokers and their family members, but these limitations should be reconsidered. First, the Court stated that a disease can be categorized as specific or non-specific, and for each disease type, causation can be proven by different types of evidence. However, the concept of specific diseases is not compatible with multifactor theory, which is generally accepted in the field of public health. Second, when the epidemiological association between the disease and the risk factor is proven to be significant, imposing additional burdens of proof on the plaintiff may considerably limit the plaintiff's right to recovery, but the Court required the plaintiffs to provide additional information such as health condition and lifestyle. Third, the Supreme Court is not giving greater weight to the evidential value of epidemiological study results because the Court focuses on the fact that these studies were group-level, not individual-level. However, group-level studies could still offer valuable information about individual members of the group, e.g., probability of causation.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.8-11
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• 2012

Purpose : Among quality control items, the radiochemical impurity must be below 10% of total radioactivity. In this regard, as the recently commercialized automatic synthesis module produces a large amount of 18F-FDG, radiolysis of radiopharmaceuticals is very likely to occur. Thus, this study compared the changes in radiochemical purity regarding radiolysis of $^{18}F$-FDG according to automatic synthesis module. Materials and methods : Cyclotron (PETtrace, GE Healthcare) was used to produce $^{18}F$ and automatic synthesis module (FASTlab, Tracerlab MX, GE Healthcare) was used to achieve synthesis into FDG. For radiochemical purity, Radio-TLC Scanner (AR 2000, Bioscan), GC (Gas Chromatograph, Agilent 7890A) was used to measure the content of ethanol included in $^{18}F$-FDG. Glass board applied with silica gel ($1{\times}10cm$) was used for stationary phase while a mixed liquid formed of acetonitrile and water (ratio 19:1) was used for mobile phase. High-concentration and low-concentration $^{18}F$-FDG were produced in each synthesis module and the radiochemical purity was measured every 2 hours. Results : The purity in low-concentration (below 2.59 GBq/mL) was measured as 99.26%, 98.69%, 98.25%, 98.09% in Tracerlab MX and as 99.09%, 97.83%, 96.89%, 96.62% in FASTlab according to 0, 2, 4, 6 hours changes, respectively. The purity in high-concentration (above 3.7 GBq/mL) was measured as 99.54%, 96.08%, 93.77%, 92.54% in Tracerlab MX and as 99.53%, 95.65%, 92.39%, 89.82% in FASTlab according to 0, 2, 4, 6 hours changes, respectively. Also, ethanol was not detected in GC of $^{18}F$-FDG produced in FASTlab, while 100~300 ppm ethanol was detected in Tracerlab MX. Conclusion : Whereas the change of radiochemical purity was only 3% in low-concentration $^{18}F$-FDG, the change was rapidly increased to 10% in high-concentration. Also, higher radiolysis were observed in $^{18}F$-FDG produced in FASTlab than Tracerlab MX. This is because ethanol is included in the synthesis stage of Tracerlab MX but not in the synthesis stage of FASTlab. Thus, radiolysis is influenced by radioactivity concentration than the inclusion of ethanol, which is the radioprotector. Therefore, after producing high-concentration $^{18}F$-FDG, the content must be diluted through saline to lower concentration.