• Journal of Environmental Health Sciences
• /
• v.40 no.3
• /
• pp.215-224
• /
• 2014

Objective: This study was carried out in order to determine the depositional characteristics of pine needles, pine bark, and soil used as a passive air sampler (PAS) for atmospheric polybrominated diphenyl ethers (PBDEs). Methods: All three media were sampled from the same site. The PBDE concentrations were analyzed by HRGC/HRMS, and the lipid contents were measured using the gravimetric method by n-hexane extraction. Results: The total PBDE concentration was the highest in soil (22,274.57 pg/g dry), followed by pine bark (20,266.39 pg/g dry), and then pine needles (7,380.22 pg/g dry). Pine needles contained the highest lipid contents (21.31 mg/g dry), whereas soil (10.01 mg/g dry), and pine bark (4.85 mg/g dry) contained less. There were poor correlations between lipid content and total PBDE concentrations in the media ($R^2$=0.8216, p=0.2814). Congeners BDE 47, 99, 183, 196, 197, 206, 207 and 209 showed peak concentrations. Among these, BDE 206, 207, and 209 are highly brominated PBDEs that exist as particulates in ambient air. They accounted for 81.2% [69.2 (pine needles) - 89.0% (tree bark)] of the concentration and therefore are noted as the main congener of the total PBDEs. Conclusions: It can therefore be concluded that for reducing error by improper sampling, the same species of media should be recommended for use as a PAS for atmospheric PBDEs due to the differences in depositional characteristics.

• Journal of IKEEE
• /
• v.25 no.3
• /
• pp.565-570
• /
• 2021

This paper describes UL 4600, a new international safety standard to ensure safety of autonomous cars. Conventional vehicular safety standards such as ISO 26262 and ISO/PAS 21448 suffer from large limitations to be applied to autonomous cars, but UL 4600 exploits new approaches to be applied to autonomous cars. Conventional standards define various technological aspects to ensure safety and require manufacturers to certify these aspects. On the contrary, UL 4600 requires manufacturer to explain and prove why autonomous cars are safe. In UL 4600, (1) under specific environments where the system is designed to operate with, (2) claims should be defined to guarantee given safety, and (3) arguments should be suggested to satisfy given goals, and (3) evidences should be presented to prove given arguments. UL 4600 is technology-neutral since it does not require specific designs nor technologies. So UL 4600 only requires manufacturers to prove given safety goals regardless of methods and technologies. Also UL 4600 admits various cases of autonomous car field operations into the standard via feedback loop. So UL 4600 effectively maneuvers various dangers unknown at the time of standard establishment.

• Asian Spine Journal
• /
• v.12 no.6
• /
• pp.981-986
• /
• 2018

Study Design: Retrospective case series. Purpose: Cauda equina syndrome (CES) is associated with etiologies such as lumbar disc herniation (LDH) and lumbar canal stenosis (LCS). CES has a prevalence of 2% among patients with LDH and exhibits variable outcomes, even with early surgery. Few studies have explored the factors influencing the prognosis in terms of bladder function. Therefore, we aimed to assess the factors contributing to bladder recovery and propose a simplified bladder recovery classification. Overview of Literature: Few reports have described the prognostic clinical factors for bladder recovery following CES. Moreover, limited data are available regarding a meaningful bladder recovery status classification useful in clinical settings. Methods: A single-center retrospective study was conducted (April 2012 to April 2015). Patients with CES secondary to LDH or LCS were included. The retrieved data were evaluated for variables such as demographics, symptom duration, neurological symptoms, bladder symptoms, and surgery duration. The variable bladder function outcome during discharge and at follow-up was recorded. All subjects were followed up for at least 2 years. A simplified bladder recovery classification was proposed. Statistical analyses were performed to study the correlation between patient variables and bladder function outcome. Results: Overall, 39 patients were included in the study. Majority of the subjects were males (79.8%) with an average age of 44.4 years. CES secondary to LDH was most commonly seen (89.7%). Perianal sensation (PAS) showed a significant correlation with neurological recovery. In the absence of PAS, bladder function did not recover. Voluntary anal contraction (VAC) was affected in all study subjects. Conclusions: Intactness of PAS was the only significant prognostic variable. Decreased or absent VAC was the most sensitive diagnostic marker of CES. We also proposed a simplified bladder recovery classification for recovery prognosis.

• Journal of Nutrition and Health
• /
• v.54 no.2
• /
• pp.129-138
• /
• 2021

To set the estimated energy requirement (EER) in Dietary Reference Intakes for Koreans (KDRI), we need the coefficient by physical activity stage, as determined by the physical activity level(PAL). Thus, there has been demand for a tool to calculate PAL based on the physical activity diary. This study was undertaken to develop a physical activity (PA) classification table for Koreans, using the 2011 Compendium of physical activities in the United States. The PA classification table for Koreans contains 262 codes, and values of the metabolic equivalent of task (MET) for specific activities. Of these, 243 PAs which do not have Korean specific data or information, were selected from the 2011 Compendium of PAs that originated in the United States; another 19 PAs were selected from the previous research data of Koreans. The PA classification table is codified to facilitate the selection of energy values corresponding to each PA. The code for each PA consists of a single letter alphabet (activity category) and four numeric codes that display the activity type (2 digit number), activity intensity (1 digit number), and specific activities (1 digit number). In addition, the intensity (sedentary behavior, low, middle and high) of specific PA and its rate of energy expenditure in MET are presented together. The activity categories are divided into 4 areas: Daily Activity (A), Movement (B), Occupation (C), and Exercise and Sports (D). The developed PA classification table can be applied to quantify the energy cost of PA for adults in research or practice, and to assess energy expenditure and physical activity levels based on self-reported PA.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.47 no.4
• /
• pp.31-37
• /
• 2010

In this paper, highly efficient dual-band class-F power amplifiers(PAs) for cellular and WLAN bands are suggested and implemented. For the first step, single-band class-F amplifiers at 840MHz, 2.4GHz are designed using commercial E-pHEMT FETs. The performance of two single band PAs are as much as 81.2% of efficiency with the output power of 24.4dBm with 840MHz PA and 93.5% of efficiency with 22.4dBm from the 2.4GHz. For the dual-band class-F PA, the harmonic controlling circuit with ideal SPDT switch was suggested. The length of transmission line is variable by a SPDT switch. As a results, the operation in 840MHz showed the peak efficiency of 60.5% with 23.5dBm, while in 2.4GHz mode the efficiency was 50.9% with the output power of 19.62dBm. Besides, it is shown that the harmonic controller of class-F above 2Ghz could be implemented on the low cost FR-4 substrate.

• Clinical and Experimental Pediatrics
• /
• v.61 no.6
• /
• pp.187-193
• /
• 2018

Purpose: The efficacy of percutaneous stent implantation for congenital heart disease (CHD) in Korea, where stent availability is limited, has not been determined. This study evaluated the acute and midterm results of stent implantation in different CHD subgroups. Methods: Stents were implanted in 75 patients with 81 lesions: (1) pulmonary artery stenosis (PAS) group, 56 lesions in 51 patients; (2) coarctation of the aorta (CoA) group, 5 lesions in 5 patients; (3) Fontan group, 13 lesions in 12 patients; (4) ductal stent group, 3 lesions in 3 patients; and (5) other CHD group, 4 lesions in 4 patients. Mean follow-up duration was 2.1 years (0.1-4 years). Medical records were reviewed retrospectively. Results: The minimum lumen diameter (MLD) in PAS and CoA increased from $5.0{\pm}1.9mm$ and $8.4{\pm}1.6mm$ to $10.1{\pm}3.6mm$ and $12.3{\pm}2.5mm$, respectively (P<0.01). In the PAS group, pressure gradient decreased from $25.7{\pm}15.6mmHg$ to $10.4{\pm}10.1mmHg$, and right ventricular to aortic pressure ratio from $0.56{\pm}0.21$ to $0.46{\pm}0.19$. In the CoA group, the pressure gradient decreased from $50{\pm}33mmHg$ to $17{\pm}8mmHg$. In the ductal stent group, the MLD of the ductus increased from 2.3 mm to 4.3 mm and arterial oxygen saturation from 40%-70% to 90%. No deaths were associated with stent implantation. Stent migration occurred in 3 patients, but repositioning was successful in all. Stent redilation was performed successfully in 26 cases after $29{\pm}12months$. Conclusion: Percutaneous stent implantation was safe and effective, with acceptable short and mid-term outcomes in Korean CHD patients.

• Clinical and Experimental Pediatrics
• /
• v.52 no.11
• /
• pp.1279-1282
• /
• 2009

Hepatomegaly and liver dysfunction might develop in patients with diabetes mellitus due to glycogen deposition or nonalcoholic steatohepatitis. We experienced a case of hepatic glycogenosis in a patient with type 1 diabetes mellitus who presented with recurrent hypoglycemia, suggesting impairment of glycogenolysis and gluconeogenesis. A 10-year-old girl with a 4-year history of type 1 diabetes mellitus was admitted because of recurrent hypoglycemia and abdominal pain in the right upper quadrant. She had Cushingoid features and hepatomegaly that extended 6 cm below the right costal margin. Laboratory data and radiologic examination revealed elevated liver enzyme levels due to fatty liver. Periodic acid-Schiff (PAS) staining revealed intense glycogen deposition in the cytoplasm of the hepatocytes and PAS reactivity was lost with diastase treatment. At 2 months after administration of glucagon injection and uncooked cornstarch between meals and at bedtime, the hypoglycemic episodes and liver dysfunction improved. It is important to distinguish hepatic glycogenosis from steatohepatitis, because it is possible to prevent excessive hepatic glycogen storage in hepatic glycogenosis cases by strictly controlling blood glucose level and by glucagon administration. To prevent severe hypoglycemic symptoms accompanied by hepatic glycogenosis, we suggest that uncooked cornstarch, which is effective in maintaining blood glucose level, can also be administered.

• Journal of Life Science
• /
• v.15 no.5 s.72
• /
• pp.707-714
• /
• 2005

The conventional histochemical staining were used to study mucosubstances properties of intestinal striated border and goblet cells in four teleostean species, i. e., Sebastes schlegeli, Halichoeres poecilopterus, Bryzoichthys lysimus, and Takifugu pardalis. The following methods were used; PAS, AB pH 2.5, AB pH 1.0, AB pH 2.5-PAS, AF pH 1.7-AB pH 2.5 and HID-AB pH 2.5 stains. The mucosubstances of striated border in the proximal intestine and rectum of Sebastes schlegeli contained with neutral mucin, middle and distal intestine contained with neutral mucin and acid mucin. The striated border of all the intestines of Halichoeres poecilopterus contained with neutral mucin and acid mucin, and those of Bryzoichthys lysimus and Tnkifugu pardalis contained with neutral mucin only. The amounts of neutral mucin were moderate to considerable in Sebastes schlegeli and Halichoeres poecilopterus, minimal to small in Bryzoichthys lysimus and Tnkifugu pardalis. The amounts and properties in mucosubstances of intestinal goblet cells showed differences in species and regions. The intestinal goblet cells of Bryzoichthys lysimus, and Tnkifugu pardalis contained neutral mucin only while Sehastes schlegeli and Halichoeres poecilopterus contained mixture of neutral mucin, sulfomucin and sialomucin. The amounts of neutral mucin were considerable to large in distal intestine and rectum of Tnkifugu pardalis, while moderate to considerable in all intestines of Sehastes schlegeli, all the intestines except for middle intestine of Bryzoichthys lysimus, and proximal and middle intestine of Tnkifugu pardalis. Also it was minimal to small in middle intestine of Halichoeres poecilopterus. The intestinal goblet cells of Sehastes schlegeli contained mixture of minimal amounts of strong sulfmucin, weak sulfomucin and minimal to small amounts of sialomucin, and those of Halichoeres poecilopterus except for rectum contained mixture of minimal to small amounts of strong sulfomucin and sialomucin.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.6
• /
• pp.1123-1142
• /
• 1998

Background : The frequency of MOTT has risen as the prevalence of tuberculosis has been declining. Our country has been also. The most of MOTT was resistant to the major anti-tuberculous drugs. Method : To compare clinical characteristics and frequencies of MDR tuberculosis with MOTT, the author studied 65 patients showing AFB culture positive with sputum. The data were collected from 176 patients who had been admitted at the National Masan Tuberculosis Hospital from May to June, 1997 to April, 1998. Result : The frequency of MDR tuberculosis was 43.1% and that of MOTT was 9.2%. Among 65 isolated mycobacteria, 3 cases were M. intracellulare. 2 cases were M. fortuitum, and 1 case was unidentified MOTT. The most frequent age group in 65 culture positive patients was 4th decade and the mean age was 44. The mean age was 61 in MOTT and 42 in M. tuberculosis and had significant difference(p<0.01). The numbers with past history of treatment were 2.3 in MDR tuberculosis and 1.7 in non-MDR tuberculosis and had significant difference(p<0.05). At the time of admission, the most frequent regimen for the treatment of MDR tuberculosis was 24 months regimen(85.7%) with the 2nd line anti-tuberculosis drugs. For non-MDR tuberculosis, 9 or 12 months regimen (72.9%) with the 1st line anti-tuberculosis drugs and had significant difference (p<0.01). At the time of admission, the symptom of weight loss was shown in 84.7% of M. tuberculosis and 50.0% in MOTT and there was significant difference(p<0.05) between them. All of the MOTT were identified to be resistant against INH and PAS. Drug resistance rates to INH, OFX(p<0.01) and PAS(p<0.05) in MOTT were higher than in MDR. All of three M. intracellulare strains were resistant to INH, RFP, PAS and OFX. All of two M. fortuitum strains were resistant to most anti-tuberculosis drugs. And the other MOTT was resistant to INH, EMB and PAS. Conclusion : MOTT was more common in elderly patients than M. tuberculosis. MOTT cases should be considered to be the probability of multiple drug resistance and treatment failure during the 1st treatment because they showed more resistance to anti-tuberculosis drugs than M. tuberculosis cases. Therefore, there should be more careful investigations for clinical characteristics, natural history of disease, and efficient management for MOTT.

• Journal of Life Science
• /
• v.17 no.12
• /
• pp.1669-1674
• /
• 2007

The conventional histochemical stains were used to study the properties of mucosubstances of the intestine in four teleostean species, i. e., Agramus agramus, Inimicus japonicus, Epinephelus chlorostigma, and Helicolenus dactylopterus, all belonging to the order Perciformes. The following methods were used; periodic acid Schiff (PAS), alcian blue (AB) pH at 2.5, AB pH at 1.0, AB pH at 2.5-PAS, and aldehyde fuchsin (AF) pH at 1.7-AB pH at 2.5 stain. The mucosal folds of intestines show differences in species and regions. Widely distributed in all portions studied, goblet cells situated between cylinderical epithelial cells are round or ovoid in shape. They were most densely distributed in distal intestine. In the middle and. distal intestine of Epinephelus chlorostigma and all regions of intestines of Agramus agramus, Inimicus japonicus, and Helicolenus dactylopterus, the presence of both acidic and neutral mucin was confirmed. The property of acidic mucosubstance was sialomucin. Neutral mucin was only encountered in the proximal intestine of Epinephelus chlorostigma. The amount and property of mucin showed differences in species and regions. In the distal intestine of Inimicus japonicus, the amount of acidic mucin is similar to that of neutral mucin. In all regions of intestine of Agramus agramus, proximal and middle intestine of lnimicus japonicus, middle and distal intestine of Epinephelus chlorostigma, and distal intestine of Helicolenus dactylopterus, acidic mucin occured more frequently than neutral mucin. The proximal and middle intestine of Helicolenus dactylopterus have more neutral mucin than acidic mucin.