신축학교 실내공기질이 초등학생들의 인지기능에 미치는 영향

김태섭,김선주,박시영,전만중,김규태,김창윤,정종학,백성옥,사공준 대한산업의학회 2007 대한직업환경의학회지 Vol.19 No.1

목적: 신축초등학교와 대조학교를 선정하여 교실 내 포름알데히드와 TVOCs를 측정하고 컴퓨터 신경행동검사를 이용하여 실내공기 오염물질이 학생들의 인지기능에 미치는 영향을 평가하였다. 방법: 신축초등학교 5학년 71명을 실내공기 오염물질 노출군으로 하고, 개교한지 12년째인 대구시의 일개 초등학교 5학년 2학급 63명을 대조군으로 하여 실내공기 오염물질농도 측정 및 컴퓨터 신경행동검사를 실시하였다. 결과: 신축학교에서 의도적으로 창문을 개방한 학급에서 1교시 포름알데히드 농도는 34.6 ㎍/㎥, 4교시에는 27.3 ㎍/㎥, 창문을 개방하지 않은 학급에서 1교시 80.2 ㎍/㎥, 4교시 127.1 ㎍/㎥, 대조학교에서는 2학급 각각 1교시에 12.6 ㎍/㎥, 7.5 ㎍/㎥, 4교시에 19.8 ㎍/㎥, 25.2 ㎍/㎥였다. TVOCs의 경우 신축학교의 의도적으로 창문을 개방한 학급에서 1교시에 농도는 487.2 ㎍/㎥, 4교시에 428.2 ㎍/㎥, 창문을 개방하지 않은 학급에서 1 교시에 농도는 1,283.5 ㎍/㎥, 4교시에 1,715.4 ㎍/㎥, 대조학교의 경우 2학급에서 각각 1교시에 농도는 240.9 ㎍/㎥, 150.8 ㎍/㎥, 4교시에 농도는 371.9 ㎍/㎥, 448.0 ㎍/㎥였다. 부호숫자 짝짓기의 평균반응시간은 대조학급이 1교시에 2,585 msec에서 4교시에 2,459 msec으로 감소한 반면 신축학교의 창문을 의도적으로 개방한 학급은 2,343 msec에서 2,510 msec으로, 평소대로 수업한 학급은 2,340 msec에서 2,563 msec으로 반응시간이 각각 167 msec, 223 msec 증가하였다. 1교시의 부호숫자 짝짓기 의 반응시간을 100%로 했을 때 창문을 의도적으로 개방 한 학급은 4교시에 5.9% 증가하였고(p<0.01), 평소대로 수업한 학급은8.3% 증가하였다(p<0.01). 반면에 대조학급은 4교시에 5.0% 감소하였다(p<0.01). 결론: 향후 학교의 실내공기질의 안전성 평가는 샘플링 된 공기의 오염수준의 측정뿐만 아니라 학생들의 건강영향도 함께 고려되는 것이 바람직할 것이다. Objectives: Most studies on the indoor air quality of newly built schools have focused only on the number of schools exceeding a standard or on subjective symptoms, such as sneezing, irritated eyes and an irritated nose. However, there has been no report on how poor indoor air quality affects children's academic performance. This study evaluated the effects of indoor air quality on the neurobehavioral performance of elementary school children. Methods: This study measured the indoor air pollutants and compared children's performance, using a computerized neurobehavioral test, between a newly built and a 12-year-old school. In addition, a questionnaire was administered regarding the indoor air quality related symptoms of children in a newly built and a 12-year-old school. Results: In the newly built school, the formaldehyde levels in the 1^(st) and 4^(th) classes with an open window were 34.6 and 27.3 μg/㎥, respectively. The levels in the 1^(st) and 4^(th) classes with the window closed were 80.2 and 127.1 μg/㎥, respectively. In the 12-year-old school, the formaldehyde levels in 1^(st) and 4^(th) class with open and closed window were 12.6 and 7.5 μg/㎥, and 19.8 and 25.2 μg/㎥, respectively. With respect to total volatile organic compounds, the levels in the 1^(st) and 4^(th) classes with the window open in the newly built school were 87.2 and 428.2 μg/㎥, respectively. In the 1^(st) and 4^(th) classes with the window closed, the total volatile organic compounds were 1,283.5 and 1,715.4 μg/㎥, respectively. In the 12-year-old school, the total volatile organic compounds were 240.9 and 150.8 μg/㎥, and 371.9 and 448.0 μg/㎥ in the 1^(st) and 4^(th) classes, respectively. In the case of a newly built school, the performance of the students in the neurobehavioral test in the 4^(th) class with the window closed was 8.3% lower than for those in the 1^(st) class with the window closed, but was only 5.9% lower when the windows were open. There was a statistical significant difference in the total numbers of symptoms between the two schools. Conclusions: These results suggest a proper evaluation of the indoor air quality within schools is required into both the level of contamination and the health effects of these contaminants toward children.

Temporal evolution of programmed death-ligand 1 expression in patients with non-small cell lung cancer

( Chang Hyun Nam ),( Jaemoon Koh ),( Chan-young Ock ),( Miso Kim ),( Bhumsuk Keam ),( Tae Min Kim ),( Yoon Kyung Jeon ),( Dong-wan Kim ),( Doo Hyun Chung ),( Dae Seog Heo ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.4

Background/Aims: Programmed death-ligand 1 (PD-L1) expression, a validated predictive biomarker for anti-PD-1/PD-L1 inhibitors, is reported to change over time. This poses challenges during clinical application in non-small cell lung cancer. Methods: This study included patients with non-small cell lung cancer who underwent surgery or biopsy and evaluation of PD-L1 expression in tumor cells via immunohistochemistry more than twice. We set the threshold of PD-L1 positivity to 10% and categorized patients into four groups according to changes in PD-L1 expression. Clinicopathologic information was collected from medical records. Statistical analyses, including Fisher’s exact test and log-rank test, were performed. Results: Of 109 patients, 38 (34.9%) and 45 (41.3%) had PD-L1 positivity in archival and recent samples, respectively. PD-L1 status was maintained in 78 (71.6%) patients, but changed in 31 (28.4%), with 19 (17.4%) from negative to positive. There were no significant differences in characteristics between patients who maintained PD-L1 negativity and whose PD-L1 status changed from negative to positive. Patients harboring PD-L1 positivity in either archival or recent samples achieved better responses (p = 0.129) and showed longer overall survival than those who maintained PD-L1 negativity when they received immune checkpoint inhibitors after platinum failure (median overall survival 14.4 months vs. 4.93 months; hazard ratio, 0.43; 95% confidence interval, 0.20 to 0.93). Conclusions: PD-L1 status changed in about one-fourth of patients. PD-L1 positivity in either archival or recent samples was predictive of better responses to immune checkpoint inhibitors. Therefore, archival samples could be used for assessment of PD-L1 status. The need for new biopsies should be decided individually.

Effect of Soybean Meal and Soluble Starch on Biogenic Amine Production and Microbial Diversity Using In vitro Rumen Fermentation

Jeong, Chang-Dae,Mamuad, Lovelia L.,Kim, Seon-Ho,Choi, Yeon Jae,Soriano, Alvin P.,Cho, Kwang Keun,Jeon, Che-Ok,Lee, Sung Sil,Lee, Sang-Suk Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.1

This study was conducted to investigate the effect of soybean meal (SM) and soluble starch (SS) on biogenic amine production and microbial diversity using in vitro ruminal fermentation. Treatments comprised of incubation of 2 g of mixture (expressed as 10 parts) containing different ratios of SM to SS as: 0:0, 10:0, 7:3, 5:5, 3:7, or 0:10. In vitro ruminal fermentation parameters were determined at 0, 12, 24, and 48 h of incubation while the biogenic amine and microbial diversity were determined at 48 h of incubation. Treatment with highest proportion of SM had higher (p<0.05) gas production than those with higher proportions of SS. Samples with higher proportion of SS resulted in lower pH than those with higher proportion of SM after 48 h of incubation. The largest change in $NH_3$-N concentration from 0 to 48 h was observed on all SM while the smallest was observed on exclusive SS. Similarly, exclusive SS had the lowest $NH_3$-N concentration among all groups after 24 h of incubation. Increasing methane ($CH_4$) concentrations were observed with time, and $CH_4$ concentrations were higher (p<0.05) with greater proportions of SM than SS. Balanced proportion of SM and SS had the highest (p<0.05) total volatile fatty acid (TVFA) while propionate was found highest in higher proportion of SS. Moreover, biogenic amine (BA) was higher (p<0.05) in samples containing greater proportions of SM. Histamines, amine index and total amines were highest in exclusive SM followed in sequence mixtures with increasing proportion of SS (and lowered proportion of SM) at 48 h of incubation. Nine dominant bands were identified by denaturing gradient gel electrophoresis (DGGE) and their identity ranged from 87% to 100% which were mostly isolated from rumen and feces. Bands R2 (uncultured bacterium clone RB-5E1) and R4 (uncultured rumen bacterium clone L7A_C10) bands were found in samples with higher proportions of SM while R3 (uncultured Firmicutes bacterium clone NI_52), R7 (Selenomonas sp. MCB2), R8 (Selenomonas ruminantium gene) and R9 (Selenomonas ruminantium strain LongY6) were found in samples with higher proportions of SS. Different feed ratios affect rumen fermentation in terms of pH, $NH_3$-N, $CH_4$, BA, volatile fatty acid and other metabolite concentrations and microbial diversity. Balanced protein and carbohydrate ratios are needed for rumen fermentation.

자동차용 비접촉식 조향 토크 센서에 관한 연구

전창남(Chang-nam Jeon),양현일(Hyun-il Yang),전민석(Min-seok Jeon),이석우(Seag-woo Lee),정이화(Lee-wha Jung),공준호(Jun-ho Gohng),조남규(Nam-kyu Cho),이대성(Dae-sung Lee) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11

We have studied the automotive non-contacted torque sensor of magnetic shielding type for MDPS or EPS, which includes Hall IC, circular permanent magnets and apparatus of magnetic shield using soft ferromagnetic material. This sensor is mounted to torsion bar connected steering column ? shaft assembly. Some samples were made by the magnetic shield concept design and performance tests were carried out.

온라인/오프라인 조명시설 관리 프로그램의 개발

전창대(Chang Dae Jeon),장병건(Byong Kun Chang) 한국조명·전기설비학회 2004 한국조명·전기설비학회 학술대회논문집 Vol.2004 No.11월

This paper concerns developing a real time on-line light facility management system using internet and building a database system for control box and street light. Also, we designed the system to minimize the disparity with the conventional management system by referring to a old management ledger format. Thus, the proposed method may enable the system manager to administer the light facility efficiently and to reduce the manpower cost, and time economically.

자기 차폐방식을 적용한 자동차용 비접촉식 토크센서에 관한 연구

전창남(Chang-Nam Jeon),한창규(Chang-Kyu Han),양현일(Hyun-il Yang),전민석(Min-Seok Jeon),이석우(Seag-Woo Lee),조남규(Nam-Kyu Cho),이대성(Dae-Sung Lee) 한국자동차공학회 2009 한국자동차공학회 부문종합 학술대회 Vol.2009 No.4

The present paper relates to a study on automotive non-contacted torque sensor for MDPS or EPS, which includes Hall IC, circular permanent magnet and apparatus of magnetic shield using soft ferromagnetic material and is mounted to torsion bar connected steering column ? shaft assembly. Torque sensor can be promptly and precisely measured by change of magnetic field to loaded twist torque when a driver operates steering wheel and can be obtained better durability then contacted type such as using strain gauge or potentiometer.

간신증후군에서의 Somatostatin 의 효과

전창호(Chang Ho Jeon),이창환(Chang Hwan Lee),송항용(Hang Young Song),천기태(Gi Tae Chun),권철(Chul Kwon),이수택(Soo Taik Lee),김대곤(Dae Ghon Kim),안득수(Duek Soo Ahn) 대한내과학회 1994 대한내과학회지 Vol.47 No.5

N/A Objectives: Decreased glomerular filtration rate, low urine output, sodium retention, and ascites formation associated with impaired water excretion and dilutional hyponatremia often complicate the course of patients with cirrhosis of the liver. Somatostatin, an agent that causes selective splanchnic arteriolar vasoconstriction and decreases portal and collateral blood flow and portal pressure, is widely used in cirrhotic patients for the treatment of acute vriceal bleeding and cirrhotic patients with ascites. We performed this study to evaluate the effect of somatostatin analogue on renal function of cirrhotic patients with hepatorenal syndrome. Methods: The effect of somatostatin analogue on renal function was investigated in 15 cirrhotic patients with hepatorenal syndrome with low urine output, low serum sodium, and increased serum creatinine. somatostatin analogue (octreotide) 50 ug was injected subcutaneously for 3 days. Results: The probability of hepatorenal syndrome occurrence was more common in viral hepatitis induced cirrhosis than alcoholic cirrhosis. In the patients with hepatorenal syndrome, octreotide induces a significant increase in urine volume (before injection 450±35.9 vs. 1st day 620±46.2, 2nd day 1190±160.9, 3rd day 896±141.4 ml/dl), a significant decrease urine osmolarity (before injection 526±63 vs. 1st day 445±69, 2nd day 430±56, 3rd day 438±61 mOsm/kg), and significant increase in free water clearance (before injection-0.4±0.3 vs.-lst day 0.5±0.1, 2nd day 0.6±0.2, 3rd day 0.5±0.1 ml/min). Conclusion: The effect of somatostatin might be attributed to an improvement of renal hemodynamics through splanchnic vasoconstriction in hepatorenal syndrome. It is concluded that somatostain may have a role in the treatment of the renal abnormalities complicating liver disease.

조명시설 통합관리 시스템 개발에 관한 연구

전창대(Chang Dae Jeon),장병건(Byong Kun Chang),김영주(Young Joo Kim) 한국조명·전기설비학회 2005 한국조명·전기설비학회 학술대회논문집 Vol.2005 No.11월

This paper concerns developing a integrated online.offline light facility management system for light facility using internet and building a database system for control box and street light. Also, we designed the system to minimize the disparity with the conventional management system by referring to a old management ledger format. Thus, the proposed method may enable the system manager to administer the light facility efficiently and to reduce the manpower cost, and time economically.

Design of Emergency Heart Rate Measurement Algorithm using Fast Fourier Transform

Min-Ho Jeon,Dae-Hee Lee,Chang-Heon Oh 한국정보통신학회 2017 2016 INTERNATIONAL CONFERENCE Vol.9 No.1

Lately, the most commonly used information for estimating the wearer"s condition is heart rate information. However, the existing heart rate measurement algorithm uses the waveform interval between the maximum value and the minimum value of the heart rate signal. But, existing algorithm had delay problem that takes about 4~5 seconds to measure the heart rate. In this paper, we proposed a fast heart rate measurement algorithm based on FFT algorithm for first aid. That estimate pulse value by frequency of the measured low level heart rate signal using the FFT. As a result, it was confirmed change of frequency interval according to the heart rate information, and the changed frequency coincided with the heart rate.

간 종양의 방사선치료에서 위내용적과 종양 위치 간의 관계

전미진,이창걸,이익재,최원훈,최윤선,신동봉,김종대,김세준,하진숙,조윤진,Jeon, Mi-Jin,Lee, Chang-Geol,Lee, Ik-Jae,Choi, Won-Hoon,Choi, Yun-Sun,Shin, Dong-Bong,Kim, Jong-Dae,Kim, Sei-Joon,Ha, Jin-Suk,Cho, Yoon-Jin 대한방사선치료학회 2010 대한방사선치료학회지 Vol.22 No.2

Purpose: It aims to evaluate the location change and tendency of hepatic and intrahepatic tumors according to gastric volume and change of location. Materials and Methods: It studied 9 patients with hepatic tumors who visited Gangnam Severance Hospital from March 2009 to April 2010 and who underwent CT or PET (Positron Emission Tomography) within 2 weeks before CT-simulation. The patients fasted for 6 hours before CT-simulation and drank 240~250 cc of water just before CT or PET for image fusion. Those two types of images were fused to RTP (Radiation Treatment Planning, Pinnacle 8.0h) focusing on bone structure of individual patients. Results: They drank 240~260 cc of water but their stomach volume after drinking water varied from 259.3 cc to 495.4 cc. Even though individual differences existed in the change of stomach volume before and after drinking water, the volume was increased by 130 cc (174%) on average. The change in absolute distance between the centers of tumors ranged from 0.52 cm to 3.04 cm (1.52 cm on average); from 0.1 cm to 1.35 cm (0.44 cm on average) in cranial-caudal direction; from 0.05 cm to 2.75 cm (1.22 cm on average) in left-right direction; and from 0.05 cm to 1.85 cm (0.33 cm on average) in ventral-dorsal direction. Conclusion: It is hard to predict the movement of tumors by observing stomach movement, due to great individual differences; however, it was observed that the location of hepatic tumors was right-sided as the stomach was filled with water. Thus, it is recommended to maintain the fastened state to secure the accuracy of hepatic tumor treatment. If it cannot maintain the fastened state, it is recommended to measure stomach volumes and movement in the patient to consider the movement of hepatic tumors before radiation treatment.