• Journal of Ecology and Environment
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• v.33 no.2
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• pp.175-186
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• 2010

This study was designed to evaluate changes in the terpene composition of 3 types of pines (Pinus densiflora, Pinus thunbergii and Pinus rigida), while decomposing their leaf litter. Needle litters were placed at two different organic layer depths, one on the surface and the other beneath the litter layer. Changes in the terpene composition of this litter were detected using a gas chromatograph-mass spectrometer. Among the monoterpenes acquired from the fresh needles of P. densiflora and P. rigida, $\alpha$-pinene (12.05% and 19.87%, respectively) was the major one, followed by $\beta$-pinene (2.90% and 14.07%). However, from the needles of P. thunbergii, $\beta$-pinene (20.77%) was the major one, followed by $\alpha$-pinene (10.79%). Among the sesquiterpenes detected in P. densiflora, trans-caryophyllene (3.12%) was the highest composition compound, whereas germacrene-D (6.09%) for P. thunbergii and 1,6-cyclodecadiene (7.41%) and endo-1-bourbonanol (7.41%) for P. rigida were the highest content compounds. However, the total amounts of terpenes decreased sharply by 40-85.4% in all three types of pine needle after 90-120 days of the experiment. The concentration of each terpene differed during decomposition, and the majority of compounds disappeared from beneath the litter layer. It was determined that three types of reducing patterns of each compound appeared on the rate of loss of concentration during decomposition; one pattern decreasing sharply during the initial period, another pattern steadily or slowly decreasing, and a newly detected pattern at low concentration occurring during decomposition.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.9
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• pp.937-944
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• 2012

The thermodynamic characteristics of a trilateral cycle with water as a working fluid have been theoretically investigated for an electric generation system to recover the waste heat of the exhaust gas from a diesel engine used for the propulsion of a large ship. As a result, when a heat source was given, the efficiencies of energy and exergy were maximized by the specific conditions of the pressure and mass flow rate for the working fluid at the turbine(expander) inlet. In this case, as the condensation temperature increased, the volume expansion ratio of the turbine could be reduced properly; however, the exergy loss of the heat source and exergy destruction of the condenser increased. Therefore, in order to recover the waste exergy from the topping cycle, the combined cycle with a bottoming cycle such as an organic Rankine cycle, which is utilized at relatively low temperatures, was found to be useful.

• Biomedical Science Letters
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• v.20 no.3
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• pp.156-161
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• 2014

It has been reported that safflower seeds have preventive effects against osteoporosis. Recently, safflower buds (SB) were found to have more useful functional ingredients than safflower seeds. In the current study, we evaluated the anti-osteoporosis effects of SB diet in ovariectomized (OVX) rats. The rats were divided into five groups; sham operated group, OVX alone group, OVX plus $17{\beta}$-estradiol ($E^2$ $10{\mu}g/kg$, i.p.) and OVX plus SB diet feeding group (0.3% or 1%). Feeding of SB diet (0.3% or 1%) to OVX rats markedly increased bone mineral density (BMD) of femurs, compared to the OVX group. The OVX rats exhibited a marked increase in trabecular separation (Tb.Sp) and this change was inhibited by the feeding of SB diet, similar to that seen with OVX+E2 group. Moreover, feeding of SB diet to OVX rats decreased the markers of bone turnover, including osteocalcin and alkaline phosphatase (ALP). These results suggest that SB extract has a bone sparing effect in OVX-induced trabecular bone loss and prevents deterioration of bone microarchitecture by suppressing the rate of bone turnover. Therefore, SB may be useful for preserving bone mass and structure in estrogen deficient women with a potential role in reducing postmenopausal osteoporosis.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.645-649
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• 2009

Liquid desiccant cooling technology can supply cooling by using waste heat and solar heat which are hard to use effectively. For compact and efficient design of a dehumidifier, it is important to sustain sufficient heat and mass transfer surface area for water vapor diffusion from air to liquid desiccant on heat exchanger. In this study, the plate type heat exchanger is adopted which has extended surface, and hydrophilic coating and porous layer coating are adopted to enhance surface wettedness. PP(polypropylene) plate is coated by porous layer and PET(polyethylene terephthalate) non-woven fabric is coated by hydrophilic polymer. These coated surfaces have porous structure, so that falling liquid film spreads widely on the coated surface foaming thin liquid film by capillary force. The temperature of liquid desiccant increases during dehumidification process by latent heat absorption, which leads to loss of dehumidification capacity. Liquid desiccant is cooled by cooling water flowing in plate heat exchanger. On the plate side, the liquid desiccant can be cooled by internal cooling. However the liquid desiccant on extended surface should be moved and cooled at heat exchanger surface. Optimal mixing and distribution of liquid desiccant between extended surface and plate heat exchanger surface is essential design parameter. The experiment has been conducted to verify effective surface treatment and distribution characteristics by measuring wall side flow rate and visualization test. It is observed that hydrophilic and porous layer coating have excellent wettedness, and the distribution can be regulated by adopting holes on extended surface.

• Journal of the Korean Society of School Health
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• v.12 no.2
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• pp.243-262
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• 1999

Today, obesity is not recognized as a disease itself but is known to be the indirect cause of much chronic illness. Obesity has an impact on psychological disorders including severe inferiority, damage of body self-image, low self-esteem, personality disorders. The results in an increase of the mortality rate. Therefore, this study attempts to discover and evaluate stressful experience in obese teenagers. For this study, 21 girl students and 19 boy students in Pusan middle or high school located were selected. The data were collected from March to May at 1999. A tape-recorder was used under the permission of the subjects to prevent the loss of spoken information and communication. This study consisted of 563 reponses from girls and 461 responses from boys which were then classified with descriptive expressions and priority classifications. The results generated 72 common elements in girls and 54 common elements in boys. From these elements 24 syntheses of hypothetical definitions and 8 identifications of the structural definitions in both girls and boys were developed. The structural and hypothetical definitions were as follows: The analysis of the data was made through a phenomenological analytic method suggested by Van kamm, which is as follows: 1. Maladjustment to school life; lack of understanding of the teacher, insufficient exercise ability, and a feeling of burden in attending the school obesity program. 2. Conflict in family relationships; lack of understanding from the family, a feeling of alienation. 3. Conflict in friend relationships; lack of understanding among friends, constant comparisons in appearance and body with friends (in girls) and estrangement from friends (in boys). 4. Conflict in acquaintance of the opposite sex; hoping to meet the opposite sex, lack of understanding of boy friends (in girls), feelings of pain, feelings of anxiety (in girls) feelings of burden (in girls) feelings of envy (in boys). 5. Negative body image: shape of body; feelings of pain; feelings of powerlessness; feelings of discomfort, and reception; emotional disorders (in boys), and change of personality (in boys). 6. Health disorder: Physical and psychological discomfort. 7. Feelings of burden in weight control; negative experiences in weight control, interference with family and friends, the difficulty in diet therapy, feelings of burden in exercise (in girls), to be teased by the public through mass media (in boys).

• Food Science of Animal Resources
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• v.35 no.1
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• pp.121-129
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• 2015

${\beta}$-agonists are anabolic compounds that promote fat loss and muscle gain, and their administration to livestock may provide economic benefits by increasing growth rate and feed efficiency. For these reasons, ${\beta}$-agonists are also commonly added to livestock feed as growth promoters. This can introduce a significant risk of secondary human poisoning through intake of contaminated meat. A new method for the simultaneous determination of three ${\beta}$-agonists (clenbuterol, ractopamine, and zilpaterol) was developed in this study and applied to various meat samples. The limits of quantification, derived through a validation test following Codex guidelines, were $0.2{\mu}g/kg$ for clenbuterol and zilpaterol, and $0.4{\mu}g/kg$ for ractopamine. The average recoveries for clenbuterol, ractopamine, and zilpaterol ranged from 109.1% to 118.3%, 95.3% to 109.0%, and 94.1% to 120.0%, respectively. The recovery and coefficient of variation (CV) values fell within the acceptable range according to the Codex guidelines. This method reduced the analysis time without decreasing detection efficiency by modifying the pretreatment steps. This method could be utilized to manage the safety of imported meat products from countries where zilpaterol use is still permitted, thereby improving public health and preventing ${\beta}$-agonist poisoning due to secondary contamination.

• Progress in Superconductivity and Cryogenics
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• v.14 no.2
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• pp.24-27
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• 2012

The superconducting coil system is one of the most important components in Korea Superconducting Tokamak Advanced Research (KSTAR), which has been operated since 2008. $Nb_3Sn$ and NbTi superconductors are being used for cable-in-conduit conductors (CICCs) of the KSTAR toroidal field (TF) and poloidal field (PF) coils. The CICCs are cooled by forced-flow supercritical helium about 4.5 K. The temperature, pressure and mass flow rate of the supercritical helium in the CICCs are interacting with each other during the operation of the coils. The complicate behaviors of the supercritical helium have an effect on the operation and the efficiency of the helium refrigeration system (HRS) by means of, for instance, pressure drop. The hydraulic characteristics of the supercritical helium have been monitored while the TF coils have stably achieved the full current of 35 kA. In other hands, the PF coils have been operated with various pulsed or bipolar mode, so the drastic changes happen in view of hydraulics. The heat load including AC loss on the coils has been analyzed according to the measurement. These activities are important to estimate the temperature margin in various PF operation conditions. In this paper, the latest hydraulic behaviors of PF coils during KSTAR operation are presented.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3647-3650
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• 2016

Background: Colorectal cancer is one of the major health problems worldwide. However, limited studies have been reported from ASEAN countries. This study was conducted to evaluate clinical characteristics and survival of colorectal cancer cases aged <65 years and ${\geq}65$ years in the central region of Thailand. Materials and Methods: Clinical information, histological features, endoscopic findings and treatment outcome were collected and reviewed from Thammasat University Hospital, Pathumthani, Thailand between November 2011 and October 2015. Results: A total of 121 colorectal cancer patients, comprising 69 men and 52 women with a mean age of 65.8 years, were included. There were 57 aged <65 years and 64 aged ${\geq}65$ years. Common presenting symptoms were abdominal pain (37%), weight loss (34%) and anemia (32%). Mean duration of symptoms prior to diagnosis was 173 days. However, longer diagnosis time was demonstrated in patients aged <65 years than age more than ${\geq}65$ years (119.4 vs 58.4 days, P-value=0.30). Colonic fungating mass was the most common endoscopic finding (64.4%) and the location was significantly more commonly left than right side of the colon, both in younger and elderly groups (87.7% vs 12.3%, P=0.02 and 70.3% vs 29.7%, P=0.02, respectively). Adenocarcinoma with moderated differentiated was the most common histology (67.3%). More than half of the patients presented with advanced stage (28.9% with TNM stage 3 and 38.8% TNM stage 4, respectively). Overall 1-year and 5-year survival rates were 76.9% and 5%. Conclusions: Most colorectal cancer patients in Thailand have adenocarcinomas and present at advanced stage with poor prognosis. Screening of high risk patients and early detection might be essential factors to improve the treatment outcome and overall survival rate of colon cancer patients in Thailand and other ASEAN countries.

• Journal of Nutrition and Health
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• v.25 no.7
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• pp.569-577
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• 1992

To study the effects of the age and the dietary protein content on Ca metabolism male rats of 1 month 6 month 12 month of age were fed experimental diets containing 5%, 15% or 50% casein for 4 weeks. Food and ca intake were higher in old rats and in high protein groups. The weight ash and Ca contents of femur and tibia were higher in old rats. The higher dietary protein level resulted in higher skeletal weigh ash and Ca contents. But high protein diet(50% casein) lead to reduced bone mineral density(ash/dry bone weight) and Ca density(Ca/dry bone weight) in 1 month old rats. Low protein diet(5% casein) on the other hand reduced the bone growth even though the bone density was higher in this group. The ill effect of low protein diet was not evident in 12 month old rats. Glomerular filteration rate(GFR) and urinary Ca excretionincreased with age and with dietary protein level especially in 12 month old rats. Serum immunoreactive parathyroid hormone(iPTH) level tended to be higher in aged rats but was not affected by dietary protein level except 1 month old rats where 50% protein group showed significantly higher value. This study showed that the dietary protein level seemed to have different effect on Ca metabo-lism in rats of different age., The low bone density in the high protein group of growing rats may be due to the higher iPTH level and increased urinary Ca. The dietary protein level however had no effects on the bone composition in aged rats even though the higher urinary Ca excretion. In conclusion this study suggests that high protein intake from young may lead to less peak bone mass and to increase the bone loss in later years, which would increase the risk for osteporosis.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.12
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• pp.1557-1566
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• 2004

A flame extinction phenomenon is a typical unsteady process in combustion. Flame extinction is characterized by various physical phenomena, such as convection, diffusion, and the production of heat and mass. Flame extinction can be achieved by either increasing the strain rate or curvature, by diluting an inert gas or inhibitor, or by increasing the thermal or radiant energy loss. Though the extinction is an inherently transient process, steady and quasi-steady approaches have been used as useful tools for understanding the flame extinction phenomenon. Recently, unsteady characteristics of flames have been studied by many researchers, and various attempts have been made to understand unsteady flame behavior, by using various extinction processes. Representative parameters for describing flame, such as flame temperature, important species related to reactions, and chemi-luminescence of the flame have been used as criterions of flame extinction. In these works, verification of each parameter and establishing the proper criterions of the extinction has been very important. In this study, a time-dependent flame temperature and an OH radical concentration were measured using optical methods, and the instantaneous change of the flame luminosity was also measured using a high-speed ICCD (HICCD) camera. We compare the unsteady extinction points obtained by three different methods, and we discuss transient characteristics of maximum flame temperature and OH radical distribution near the extinction limit.