• The Korean Journal of Physiology and Pharmacology
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• v.25 no.6
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• pp.603-611
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• 2021

Taste-responsive neurons in the nucleus of the solitary tract (NST), the first gustatory nucleus, often respond to thermal or mechanical stimulation. Alcohol, not a typical taste modality, is a rewarding stimulus. In this study, we aimed to investigate the effects of ethanol (EtOH) and/or temperature as stimuli to the tongue on the activity of taste-responsive neurons in hamster NST. In the first set of experiments, we recorded the activity of 113 gustatory NST neurons in urethane-anesthetized hamsters and evaluated responses to four basic taste stimuli, 25% EtOH, and 40℃ and 4℃ distilled water (dH₂O). Sixty cells responded to 25% EtOH, with most of them also being sucrose sensitive. The response to 25% EtOH was significantly correlated with the sucrose-evoked response. A significant correlation was also observed between sucrose- and 40℃ dH₂O- and between 25% EtOH- and 40℃ dH₂O-evoked firings. In a subset of the cells, we evaluated neuronal activities in response to a series of EtOH concentrations, alone and in combination with 32 mM sucrose (EtOH/Suc) at room temperature (RT, 22℃-23℃), 40℃, and 4℃. Neuronal responses to EtOH at RT and 40℃ increased as the concentrations increased. The firing rates to EtOH/Suc were greater than those to EtOH or sucrose alone. The responses were enhanced when solutions were applied at 40℃ but diminished at 4℃. In summary, EtOH activates most sucrose-responsive NST gustatory cells, and the concomitant presence of sucrose or warm temperatures enhance this response. Our findings may contribute to elucidate the neural mechanisms underlying appetitive alcohol consumption.

• Korean Journal of Environmental Biology
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• v.40 no.3
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• pp.247-254
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• 2022

To investigate the tolerance limit and critical thermal maximum (CTM), behavioral responses of wild goldeye rockfish Sebastes thompsoni according to exposure to high water temperature were observed using a continuous behavior tracking system. As a result, behavioral index (BI) of S. thompsoni in each temperature (20.0, 25.0, and 30.0℃) showed a significant difference (p<0.05) when compared with the value measured in a stable condition of 15.0℃. The activity level of S. thompsoni exposed to 25.0℃ decreased sharply after 20 hours. Their rest time at the bottom of experiment chamber increased, and their normal swimming and metabolic activities were disturbed. In addition, at a high water temperature of 30.0℃, S. thompsoni reached the limit of resistance and showed a sub-lethal reaction of swimming behavior, with energy consumption in the body increased and all test organisms died. In conclusion, the eco-physiological response of S. thompsoni to water temperature varied greatly depending on the fluctuation range of the exposed temperature and the exposure time. In addition, the tolerance limit of S. thompsoni to high water temperature was predicted to be 25.0-30.0℃. The maximum critical thermal that had a great influence on the survival of this species was found to be around 30.0℃.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.5
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• pp.696-701
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• 2000

Stockings are considered to be excellent in retention of heat in cool weather. This study was to investigate the physiological effects of wearing support panty stocking when exposed to the cool environment from mild environment. Five healthy female college students wearing(ST) or not wearing(NST) support panty stocking, rested at 25$\pm$1$^{\circ}C$, 50$\pm$5% R.H. and were exposed to 18$\pm$1$^{\circ}C$, 50$\pm$5% R.H. for 90 minutes. The results obtained were as follows: Rectal Temperatures were lower in ST than in NST at both environments. Skin temperatures in ST were revealed higher at $25^{\circ}C$, but lower at 18$^{\circ}C$ than in NST. Heat production and total weight loss didn't show significant difference between ST and NST. Total thermal conductance from the body to the environment was higher in ST than in NST at 18$^{\circ}C$. It was suggested that wearing support panty stocking would keep the body warm in mild environment, but facilitate heat loss from the body in cool environment.

• Structural Engineering and Mechanics
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• v.73 no.6
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• pp.667-684
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• 2020

In this article, the static responses of layered magneto-electro-thermo-elastic (METE) plates in thermal environment have been investigated through FE methods. By using Reddy's third order shear deformation theory (TSDT) in association with the Hamilton's principle, the direct and derived quantities of the coupled system have been obtained. The coupled governing equations of METE plates have been derived through condensation technique. Three layered METE plates composed of piezoelectric and piezomagnetic phases are considered for evaluation. For investigating the correctness and accuracy, the results in this article are validated with previous researches. In addition, a special attention has been paid to evaluate the influence of different electro-magnetic boundary conditions and pyrocoupling on the coupled response of METE plates. Finally, the influence of stacking sequences, magnitude of temperature load and aspect ratio on the coupled static response of METE plates are investigated in detail.

• Advances in Computational Design
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• v.1 no.1
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• pp.105-117
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• 2016

The objective of this work is to study the restraining effect in fire resistance of framed structures and to evaluate the global response of reinforced concrete frames when exposed to fire based on advanced finite element method. To study the response a single portal frame is analyzed. The effect of floor slab on this frame is studied by modeling a beam-column-slab assembly. The evolution of temperature distribution, internal stresses and deformations of the frame subjected to ISO 834 standard fire curve for both the frames are studied. The thermal and structural responses are evaluated and a comparison of results of individual members and entire structure is done. From the study it can be seen that restraining forces has significant influence on both stresses and deflection and overall response of the structure when compared to individual structural member. Among the various structural elements, columns are the critical members in fire and failure of column causes the failure of entire structure. The fire rating of various structural elements of the frame is determined by various failure criteria and is compared with IS456 2000 tabulated fire rating.

• Structural Engineering and Mechanics
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• v.64 no.6
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• pp.793-802
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• 2017

The damage of concrete due to the expansion of alkali-aggregate reaction (AAR) and thermal-chemical reactions affecting the strength of concrete is studied. The empirical equations for the variations of expansion of AAR, compressive strength and degradation of the modulus of elasticity with time, and compressive strength with degradation of the modulus of elasticity are proposed by analysing numerous experimental data. It is revealed that the expansion of AAR and compressive strength increase with time. The proposed combination of the time variations of chemical and mechanical parameters provides a satisfactory prediction of the concrete strength. Seismic analysis of the aged Koyna dam is conceded for two different long-term experimental data of concrete incorporating the proposed AAR based properties. The responses of aged Koyna dam reveal that the crest displacement of the Koyna dam significantly increases with time while the contour plots show that major principal stress at neck level reduces with time. As the modulus of elasticity decreases with ages the stress generated in the concrete structure get reduces. On the other hand with lesser value of modulus of elasticity the structure becomes more flexible and the crest displacement becomes very high that cause the seismic safety of the dam reduce.

• The Korean Journal of Pain
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• v.28 no.4
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• pp.236-243
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• 2015

Background: Chemotherapy-induced peripheral neuropathy is a major side effect of anti-cancer drugs, and our knowledge of its mechanisms is lacking. Several models for chemotherapy-induced neuropathy have been introduced. However, the outcomes of these models differ significantly among laboratories. Our object was to create a model of chemotherapy-induced neuropathy in rats with cancer. Methods: Female Sprague-Dawley rats were used. Mammary rat metastasis tumor (MRMT-1) cells were implanted subcutaneously in rats. Chemotherapy-induced peripheral neuropathy was induced by injection of cisplatin once a day for four days. The responses to mechanical and thermal stimuli were examined using von Frey filaments, acetone, and radiant heat. Results: Cisplatin (2 mg/kg/day) produced mechanical allodynia, while it did not induce cold allodynia or thermal hyperalgesia. This dose of cisplatin could work successfully against cancer. Body weight loss was not observed in cisplatin-treated rats, nor were other abnormal behaviors noted in the same rats. Conclusions: Repeated injection of intraperitoneal cisplatin induced peripheral neuropathic pain in rats. Thus, this type of rat model has broad applicability in studies related to searching for the mechanism of cisplatin-induced mechanical allodynia and agents for the treatment of neuropathic pain.

• Proceedings of the ESK Conference
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• 1997.04a
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• pp.227-246
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• 1997

With a view of to providing basic data for designing male's and female's clothes, heslthy males and females(five each) were exposed to three different environmental temperature( $20{\pm}1.0^{\circ}C$ $28{\pm}1.0^{\circ}C$,$32{\pm}1.0^{\circ}C$ in the nude. Their adaptation of skin temperature, physilogical responses, oral temperature, blood pressure, pulse rates) and psychological reactions (thermal, comfort and perceptive sweat sensations) were analyzed to be as follows; The subjects's skin temperature had a similar look of adaptation, but the stability of skin temperature differed at the $20{\pm}1.0^{\circ}C$and at the $28{\pm}1.0^{\circ}C$ Males had higher skin temperatures at three environmental temperatures, but females showed a higher temperature change at the $20{\pm}1.0^{\circ}C$ and$28{\pm}1.0^{\circ}C$ and males at the $32{\pm}1.0^{\circ}C$ Thus females were more resistant to the cold, while male were more resistant to the heat. As environmental temperature increased, oral temperature and pulse rates also grew up. Females turned higher in oral temperature and lower in blood pressure, but both sexes had a normal range of physiological reactions. Even though three environmental temperature were same changes in thermal sensation at and in perceptive sweat sensation at $28{\pm}1.0^{\circ}C$and in perceptive sweat sensation at$32{\pm}1.0^{\circ}C$ the two sexes had the same response in comfort sensation at the three environmental temperature.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2404-2412
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• 1994

A mathematical model has been developed for predicting kinematic, thermal, and solidification histories of atomized droplets during flight. Liquid droplet convective cooling, recalescence, equilibrium-state solidification, and solid-phase cooling were taken into account in the analysis of the solidification process. The spherical shell model was adopted where the heterogeneous nucleation is initiated from the whole surface of a droplet. The growth rate of the solid-liquid interface was determined from the theory of crystal growth kinetics with undercooling caused by the rapid solidification. The solid fraction after recalescence was obtained by using the integral method. The thermal responses of atomized droplets to gas velocity, particle size variation, and degree of undercooling were investigated through the parametric studies. It is possible to evaluate the solid fraction of the droplet according to flight distance and time in terms of a dimensionless parameter derived from the overall energy balance of the system. It is also found that the solid fraction at the end of recalescence is not dependent on the droplet size and nozzle exit velocity but on the degree of subcooling.

• Structural Engineering and Mechanics
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• v.65 no.1
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• pp.43-51
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• 2018

Structural modal parameters i.e. natural frequencies, damping ratios and mode shapes are dynamic features obtained either by measuring the vibration responses of a structure or by means of finite elements models. Over the past two decades, modal parameters have been used to detect damage in structures by observing its variations over time. However, such variations can also be caused by environmental factors such as humidity, wind and, more importantly, temperature. In so doing, the use of modal parameters as damage indicators can be seriously compromised if these effects are not properly tackled. Many researchers around the world have found numerous methods to mitigate the influence of such environmental factors from modal parameters and many advanced damage indicators have been developed and proposed to improve the reliability of structural health monitoring. In this paper, several vibration tests are performed on a simply supported steel beam subjected to different damage scenarios and temperature conditions, aiming to describe the variation in modal parameters due to temperature changes. Moreover, four statistical methodologies are proposed to identify damage. Results show a slightly linear decrease in the modal parameters due to temperature increase, although it is not possible to establish an empirical equation to describe this tendency.