• Fibers and Polymers
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• v.7 no.4
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• pp.450-456
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• 2006

The objectives of this study were to investigate physiological and psychological responses to the rustling sound of Korean traditional silk fabrics and to figure out objective measurements such as sound parameters and mechanical properties determining the human responses. Five different traditional silk fabrics were selected by cluster analysis and their sound characteristics were observed in terms of FFT spectra and some calculated sound parameters including level pressure of total sound (LPT), Zwicker's psychoacoustic parameters - loudness(Z), sharpness(Z), roughness(Z), and fluctuation strength(Z), and sound color factors such as ${\Delta}L\;and\;{\Delta}f$. As physiological signals, the ratio of low frequency to high frequency (LF/HF) from the power spectrum of heart rate variability, pulse volume (PV), heart rate (HR), and skin conductance level (SCL) evoked by the fabric sounds were measured from thirty participants. Also, seven aspects of psychological state including softness, loudness, sharpness, roughness, clearness, highness, and pleasantness were evaluated when each sound was presented. The traditional silk fabric sounds were likely to be felt as soft and pleasant rather than clear and high, which seemed to evoke less change of both LF/HF and SCL indicating a negative sensation than other fabrics previously reported. As fluctuation strength(Z) were higher and bending rigidity (B) values lower, the fabrics tended to be perceived as sounding softer, which resulted in increase of PV changes. The higher LPT was concerned with higher rating for subjective loudness so that HR was more increased. Also, compression linearity (LC) affected subjective pleasantness positively, which caused less changes of HR. Therefore, we concluded that such objective measurements as LPT, fluctuation strength(Z), bending rigidity (B), and compression linearity (LC) were significant factors affecting physiological and psychological responses to the sounds of Korean traditional silk fabrics.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.2
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• pp.169-183
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• 1997

We have investigated the two types of voltage-dependent outward potassium (K) currents, i.e. delayed rectifier K current ($I_{K(V)}$) and 'A-like' transient outward K current ($I_{to}$) with patch-clamp technique in single smooth muscle cells (SMCs) isolated from rabbit basilar artery, and investigated the characteristics of them. The time-courses of activation were well fitted by exponential function raised to second power ($n^2$) in $I_{K(V)}$ and fourth power ($n^4$) in $I_{to}$. The activation, inactivation and recovery time courses of $I_{to}$ were much faster than that of $I_{K(V)}$. The steady-state activation and inactivation of $I_{K(V)}$ was at the more hyperpolarized range than that of $I_{to}$ contrary to the reports in other vascular SMCs. Tetraethylammonium chloride (TEA; 10 mM) markedly inhibited $I_{K(V)}$ but little affected $I_{to}$. 4-Aminopyridine (4-AP) had similar inhibitory potency on both currents. While a low concentration of $Cd^{2+}$ (0.5 mM) shifted the current- voltage relationship of $I_{to}$ to the positive direction without change of maximum conductance, $Cd^{2+}$ did not cause any appreciable change for $I_{K(V)}$.

• Safety and Health at Work
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• v.6 no.3
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• pp.256-262
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• 2015

Background: Heart attack is the most common cause of line-of-duty death in the fire service. Daily aspirin therapy is a preventative measure used to reduce the morbidity of heart attacks but may decrease the ability to dissipate heat by reducing skin blood flow. Methods: In this double-blind, placebo-controlled, crossover study, firefighters were randomized to receive 14 days of therapy (81-mg aspirin or placebo) before performing treadmill exercise in thermal-protective clothing in a hot room [$38.8{\pm}2.1^{\circ}C$, $24.9{\pm}9.1%$ relative humidity (RH)]. Three weeks without therapy was provided before crossing to the other arm. Firefighters completed a baseline skin blood-flow assessment via laser Doppler flowmetry; skin was heated to $44^{\circ}C$ to achieve maximal cutaneous vasodilation. Skin blood flow was measured before and after exercise in a hot room, and at 0 minutes, 10 minutes, 20 minutes, and 30 minutes of recovery under temperature conditions ($25.3{\pm}1.2^{\circ}C$, $40.3{\pm}13.7%\;RH$). Platelet clotting time was assessed before drug administration, and before and after exercise. Results: Fifteen firefighters completed the study. Aspirin increased clotting time before and after exercise compared with placebo (p = 0.003). There were no differences in absolute skin blood flow between groups (p = 0.35). Following exercise, cutaneous vascular conductance (CVC) was $85{\pm}42%$ of maximum in the aspirin and $76{\pm}37%$ in the placebo groups. The percentage of maximal CVC did not differ by treatment before or after recovery. Neither maximal core body temperature nor heart rate responses to exercise differed between trials. Conclusion: There were no differences in skin blood flow during uncompensable heat stress following exercise after aspirin or placebo therapy.

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.919-925
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• 2011

A new series of manganese(II), iron(III) and cobalt(III) complexes of 14-membered macrocyclic ligand, (3,6,10,13,16,19-hexaazabicyclo[6.6.6]icosane-1,8-diamine) have been prepared and characterized by elemental analyses, IR, UV-VIS, $^1H$- and $^{13}C$- NMR spectra, magnetic susceptibilities, conductivities, and ESR measurements. Molar conductance measurements in DMF solution indicate that the complexes are electrolytes. The ESR spectrum for cobalt(III) complex in $CD_3OD+10%D_2O$ after exposure to $^{60}Co-{\gamma}$-rays at 77 K using a 0.2217 M rad $h^{-1}$ vicrad source showed $g_{\perp}$ > $g_{\parallel}$ > $g_e$, indicating that, the unpaired electron site is mainly present in the $d_z2$ orbital with covalent bond character. In this case, the ligand hyperfine tensors are nearly collinear with ${\gamma}$-tensors, so there is no major tendency to bend. Therefore, little extra delocalization via the ring lobe of the $dz^2$ orbital occurs. However, the ESR spectrum in solid state after exposure to $^{60}Co-{\gamma}$-rays at 77 K showed $g_{\parallel}$ > $g_{\perp}$ > $g_e$, indicating that, the unpaired electron site is mainly present in the $d_x2_{-y}2$ ground state as the resulting spectrum contains a large number of randomly oriented molecules provided that, the principle directions of g and A tensors. Manganese (II) complex 2, $[H_{12}LMn]Cl_4.2H_2O$, showed six isotropic lines characteristic to an unpaired electron interacting with a nucleus of spin 5/2, however, iron(III) complex 3, $[H_{12}LFe]Cl_5.H_2O$, showed spectrum of a high spin $^{57}Fe$ (I=1/2), $d^5$ configuration. The geometry of these complexes was supported by elemental analyses, IR, electronic and ESR spectral studies. Complex 1 showed exploitation in reducing the amount of electron adducts formed in DNA during irradiation with low radiation products.

• The Korean Journal of Physiology
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• v.28 no.2
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• pp.215-224
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• 1994

The presence of a calcium current $(i_{Ca^{2+}})$ passed via a specific channel was examined in the unfertilized hamster egg using the whole-cell voltage clamp technique. Pure inward current was isolated using a $Ca^{2+}-rich$ pipette solution containing 10 mM TEA. This current was independent of external $Na^+$ and was highly sensitive to the $Ca^{2+}$ concentration in the bathing solution, indicating that the inward current is carried by $Ca^{2+}$. The maximal amplitude was $-4.12{\pm}0.58nA\;(n=12)$ with 10mM $Ca^{2+}$ at -3OmV from a holding potential of -8OmV. This current reached its maximum within 20ms beyond -3OmV and decayed rapidly with an inactivation time constant $({\tau})$ of 15ms. Activation and inactivation of this $i_{Ca^{2+}}$ was steeply dependent on the membrane potential. The $i_{Ca^{2+}}$ began to activate at the lower voltage of -55 mV and reached its peak at -35 mV, being completely inactivated at potentials more positive than -40 mV. These result suggest that $i_{Ca^{2+}}$ in hamster eggs passes through channels with electrical properties similar to low voltage-activated T-type channels. Other results from the present study support this suggestion; First, the inhibitory effect of $Ni^{2+}\;(IC_{50}=13.7\;{\mu}M)$ was more potent than $Cd^{2+}\;(IC_{50}=123\;{\mu}M)$. Second, $Ba^{2+}$ conductance was equal to or below that of $Ca^{2+}$. Third, $i_{Ca^{2+}}$ in hamster eggs was relatively insensitive to nifedipine $(IC_{50}=96.6\;{\mu}M)$, known to be a specific t-type blocker. The physiological role of $i_{Ca^{2+}}$ in the unfertilized hamster eggs remains unclear. Analysis from steady-state inactivation activation curves reveals that only a small amount of this current will pass in the voltage range $(-70{\sim}-30\;mV)$ which partially overlaps with the resting membrane potential. This current has the property that it can be easily activated by a weak depolarization, thus it may trigger a certain kind of a intracellular event following fertilization which may cause oscillations in the membrane potential.

• Biomolecules & Therapeutics
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• v.24 no.3
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• pp.252-259
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• 2016

Neuropathic pain is a complex state showing increased pain response with dysfunctional inhibitory neurotransmission. The TREK family, one of the two pore domain $K^+$ (K2P) channel subgroups were focused among various mechanisms of neuropathic pain. These channels influence neuronal excitability and are thought to be related in mechano/thermosensation. However, only a little is known about the expression and role of TREK-1 and TREK-2, in neuropathic pain. It is performed to know whether TREK-1 and/or 2 are positively related in dorsal root ganglion (DRG) of a mouse neuropathic pain model, the chronic constriction injury (CCI) model. Following this purpose, Reverse Transcription Polymerase Chain Reaction (RT-PCR) and western blot analyses were performed using mouse DRG of CCI model and compared to the sham surgery group. Immunofluorescence staining of isolectin-B4 (IB4) and TREK were performed. Electrophysiological recordings of single channel currents were analyzed to obtain the information about the channel. Interactions with known TREK activators were tested to confirm the expression. While both TREK-1 and TREK-2 mRNA were significantly overexpressed in DRG of CCI mice, only TREK-1 showed significant increase (~9 fold) in western blot analysis. The TREK-1-like channel recorded in DRG neurons of the CCI mouse showed similar current-voltage relationship and conductance to TREK-1. It was easily activated by low pH solution (pH 6.3), negative pressure, and riluzole. Immunofluorescence images showed the expression of TREK-1 was stronger compared to TREK-2 on IB4 positive neurons. These results suggest that modulation of the TREK-1 channel may have beneficial analgesic effects in neuropathic pain patients.

• Science of Emotion and Sensibility
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• v.14 no.4
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• pp.503-512
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• 2011

Recently in HCI research, emotion recognition is one of the core processes to implement emotional intelligence. There are many studies using bio signals in order to recognize human emotions, but it has been done merely for the basic emotions and very few exists for the other emotions. The purpose of present study is to confirm the difference of autonomic nervous system (ANS) response in three emotions (boredom, pain, and surprise). There were totally 217 of participants (male 96, female 121), we presented audio-visual stimulus to induce boredom and surprise, and pressure by using the sphygmomanometer for pain. During presented emotional stimuli, we measured electrodermal activity (EDA), skin temperature (SKT), electrocardiac activity (ECG) and photoplethysmography (PPG), besides; we required them to classify their present emotion and its intensity according to the emotion assessment scale. As the results of emotional stimulus evaluation, emotional stimulus which we used was shown to mean 92.5% of relevance and 5.43 of efficiency; this inferred that each emotional stimulus caused its own emotion quite effectively. When we analyzed the results of the ANS response which had been measured, we ascertained the significant difference between the baseline and emotional state on skin conductance response, SKT, heart rate, low frequency and blood volume pulse amplitude. In addition, the ANS response caused by each emotion had significant differences among the emotions. These results can probably be able to use to extend the emotion theory and develop the algorithm in recognition of three kinds of emotions (boredom, surprise, and pain) by response measurement indicators and be used to make applications for differentiating various human emotions in computer system.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.196-207
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• 2019

This study was carried out to investigate the effects of C. japonica, D. morbifera, D. macropodum, I. anisatum, Q. glauca and R. indica To investigate the photosynthetic ability, chlorophyll content, chlorophyll fluorescence analysis, and physiological environmental. The photosynthetic rate, cancer respiration rate, stomatal conductance, and rate of evaporation tended to decrease as a result of drying stress in the no-water condition for 28 days. I. anisatum, Q. glauca and R. indica showed a low rate of less than 40% until 28 days of no-treatment. The total chlorophyll contents were decreased in the order of D. macropodum> D. morbifera> C. japonica> Q. glauca> M. thunbergii> R. indica> I. anisatum. Chlorophyll fluorescence analysis showed that there was no change in the qP, but after 28 days no $Fv/F_m$, $F_o$, $R_{fd}$, $NPQ_{_-LSS}$ can be a useful indicator for quantitative estimation within a short period of time with a marked reduction rate of PSII quantum yield ${\Phi}PSII$ in the rectified state by continuous light during the nominal adaptation period. In the case of I. anisatum, Q. glauca and R. indica If water management can be carried out at intervals, it may be possible to plant trees in trees and landscape trees.