• Korean Membrane Journal
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• 제6권1호
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• pp.37-43
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• 2004

Comb-type graft hydrogels composed of alginate and poly(N-isopropylacrylamide) (PNIPAAm) were prepared to manifest rapid temperature and pH sensitivity. To appear the electro-sensitivity, the polyaniline, conducting polymer, was added into the matrix. The swelling kinetics and ratios were compared under the various compositions of polyaniline. The swelling behaviors revealed that conducting polymer/hydrogel composites could control the swelling ratio and kinetics. The addition of polyaniline in the matrix improved the thermal stability in comparison with that of the hydrogel without polyaniline. In temperature sensitivity, the adding the polyaniline into the matrix decreased the degree of change in the swelling ratio. The swelling ratios continuously increased with increasing pH values. The drug release rate from the hydrogel increased with the adding the polyaniline and the applying the direct voltage to the hydrogels.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.312-315
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• 2018

Although the reversibility of 10,12-pentacosadiynoic amino meta-acid(PCDA-mBzA) against temperature and pH was reported, the modulation of reversibility by ion adsorption at terminal functional group has not been investigated. In this work, we developed a simple method for modulating the reversibility of PCDA-mBzA films upon a thermal stimulus by cadmium ion adsorption inducing the breakage of the outer hydrogen bonding of two hydrogen bonds, which are responsible for the reversible properties of PCDA-mBzA. External reflection-Fourier transform infrared (ER-FTIR) analyses revealed that the hydrogen bonding between the carboxylic acid groups was broken through ion adsorption and only a single hydrogen bond between the amide groups remained in the PCDA-mBzA polymer. In addition, PCDA-mBzA films could recover their original property through cadmium ion desorption. These results present that the transition between reversibility and irreversibility can be modulated artificially simply through the adsorption and desorption of metal ions.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.99-100
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• 2006

Orthogonally protected block copolymers of based on p-hydroxystyrene were prepared with high control via nitroxy mediated radical polymerization using an alkoxyamine as an unimolecular initiator. Thin films of partially protected block copolymer were prepared by spin or dip coating. A well defined nanostructure could be observed as a result of phase separation e.g. cylinders in a matrix oriented perpendicular or parallel to the substrate. The nanostructure of the polymeric films can be defined by the block copolymer composition and it determines surface properties and allows further, selective functionalization, e.g. via click chemistry. The thin films can be designed in a way to allow a patterning based on a thermal or photochemical stimulus.

• Journal of Periodontal and Implant Science
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• 제23권1호
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• pp.127-134
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• 1993

The purpose of this study was to observe the control effect of hypersensitivity after periodontal treatment in the 19% microcrystalline hydroxyapatite containing toothpaste for the subject of 85 persons of both sexes, who complained hypersensitivity. At 2 weeks and 4 weeks after periodontal treatment, comparison of control effect was performed between the 19% microcrystalline hydroxyapatite containing toothpaste group and control group. The result were as follows, 1. The main causes of dentin hypersensitivity are the root exposure with gingival recession and cervical abrasion. 2. The occurance rate of hypersensitive tooth in the upper jaw was higher than that of the lower jaw, and more or less, the molar area showed more occlurance of hypersensitivity than the premolar and incisor area in both jaw. 3. Patients showed very sensitive response to the thermal stimulus, especially cold stimulus. 4. Exellent control effect of hypersensitivity in 19% microcrystalline hydroxyapatite containing toothpaste group showed 83.02% at 2weeks, 92.45% at 4weeks and these values were higher than the control group. In conclusion, we find that 19% microcrystalline hydroxyapatite containing toothpaste have the control effect of hypersensitivity and the proper toothbrushing method is the key in attaining more effectiveness of the toothpaste.

• Restorative Dentistry and Endodontics
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• 제11권1호
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• pp.77-88
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• 1985

The purpose of this study was to examine the thermal diffusion through bases and restorations. The three principle types of base and two restorative materials were included in this study. They were representive brands of a zinc phosphate cement, a zinc oxide-eugenol cement, a calcium hydroxide paste, an amalgam and a composite resin (table 1). The specimens were prepared by placing the bases or restorative materials in laminated plastic molds. 5-mm diameter holes were prepared in the center of square of plastics which were 0.5, 1.0, 2.0, and 3.0mm thick respectively (fig. 1). All materials were manipulated in accordance with manufacturer's recommended proportions. All experimental procedures were carried out dividing them into eight different groups (table 2). Thermal diffusion was measured by means of digital thermometer (DP-100, RKC. instrument Inc. JAPAN) with the surface thermocouple placed on bottom surface of the specimen applying a constant source of heat and cold to the top surface of the each specimen. The thermal stimulus temperature applied on the each specimen surface was in the range of $60^{\circ}C$, $0^{\circ}C$ and $-50^{\circ}C$ respectively. The thermal change were recorded automatically on the multi-Pen recorder (R-16, Rikadenki, Co. JAPAN) connected with thermocouple tips which were centered on the bottom of the specimen. The following results were as follows, 1. Temperature diffusion was highest through amalgam and slowest through the composite resin. 2. As the thickness of restorations increased, the temperature change was decreased. 3. Thermal diffusion was slowest in the presence of zinc oxide-eugenol bases, followed by calcium hydroxide and zinc phosphate cement. 4. The efficiency of the cement bases in providing thermal insulation was dependent on their thickness beneath the restorations. 5. Thermal change was great in the range of $60^{\circ}C$ and $-50^{\circ}C$, but little in the range of $0^{\circ}C$.

• The Korean Journal of Pain
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• 제12권1호
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• pp.1-7
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• 1999

Background: To study the role of spinal alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors in pain behaviors caused by mild burn, we examined the effect of intrathecal administered ACEA 2085, which has been recently characterized as a high potency competitive AMPA receptor antagonist, on the thermal hyperalgesia state induced by mild burn. Methods: A thermal injury was induced by applying the left hind paw to a thermal surface ($52.5^{\circ}C$) for 45 sec. Thermal escape latency of the hind paw was determined using an underglass thermal stimulus. Thirty min after thermal injury, the paw withdrawal latency (PWL) in injured paw of all groups fell from 10~12 sec to 5~7 sec. At that time, ACEA 2085 (0.01~0.1 mcg) and 6-cyano-7-nitroquinoxalinedione (CNQX, 1~30 mcg) were injected through intrathecal heters in rats with mild burn injury on the right hindpaw. And then, PWL were measured in the both hindpaw every 30 minutes for about three hours. Results: The intrathecal injection of ACEA 2085 produced a dose dependent reversal of the hyperalgesia in the right hindpaw and more potent than CNQX, but had no effect upon the response latency of the normal left hind paw even at the largest doses. All effects were observed at doses that had no significant effect upon motor function. Conclusions: Intrathecal ACEA 2085, highly selective AMPA receptor antagonist produce a dose- dependent reversal of the thermal hyperalgesia evoked mild burn injury. These results suggested that spinal AMPA receptor play an important role in the hyperalgesia induced by mild burn injury.

• 항공우주기술
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• 제7권1호
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• pp.115-120
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• 2008

인공위성에 사용되는 온도 측정 센서는 서미스터(Thermistor) 와 AD590이 주로 많이 사용되고 있다. AD590은 IC chip으로 서미스터에 비해 고가이며 $1^{\circ}C$ 온도 변화에 출력 전류가 약 $1{\mu}A$ 변하는 특성을 가진다. 이에 비해 서 미스터는 온도 변화에 따라 저항 값이 변하므로 외부에서 전류나 혹은 전압 stimulus를 인가해 주어야한다. 또한 일반적으로 AD590에 비해 저가이며 NTC(Negative Temperature Coefficient)와 PTC(Positive Temperature Coefficient) 두 가지 형태의 센서가 사용되고 있다. 고 정밀 저궤도 지구관측용 인공위성의 경우 온도에 따른 카메라 구조물의 변형이 최종 영상 품질에 영향을 미치게 되므로 고 품질의 영상획득을 위하여 카메라 구조물의 정밀 온도 제어가 필수적으로 요구되며 이를 구현하기 위해서 매우 정확한 온도측정 요구조건이 주어지게 된다. 저궤도 인공위성의 경우 카메라 시스템에 부착된 온도센서의 측정 정확도 요구조건이 $0.3^{\circ}C$ 까지 요구되는 경우도 있다. 본 논문은 저 궤도 인공위성에 적용된 서 미스터의 온도 측정 정확도에 대한 분석 내용을 나타내었다.

• The Korean Journal of Physiology
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• 제30권1호
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• pp.85-96
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• 1996

Adenosine and its analogues are known to possess analgesic effects and to be involved in the opiate-induced antinociception as well. This study was designed to investigate the effects of three adenosine agonists, 5'- (N-cyclopropyl) -carboxamidoadenosine(CPCA), 5'-N-ethylcarboxamidoadeno-sine (NECA) and $N^6-cyclohexyladenosine$ (CHA) on the signal transmission in the spinal cord and also to elucidate mechanisms of their actions in the anesthetized cat. All the tested adenosine agonists(i.v,) exerted inhibitory effects on the responsiveness of the wide dynamic range (WDR) cells, the inhibitory action of CHA, an adenosine $A_1$ receptor agonist, $(80{\mu}g/Kg)$ being most weak. The intravenous CPCA, an adenosine $A_2$ receptor agonist, $(20{\mu}g\;/Kg)$ and NECA, nonspecific adenosine receptor agonist, $(20{\mu}g\;/Kg)$ inhibited the responses of WDR cells to pinch and C fiber stimulation more strongly than those to brush and A fiber stimulation. CPCA (i.v.) also suppressed the responses of WDR cells to thermal stimulus. And all the CPCA-induced inhibitions were caffeine-reversible. When CPCA was directly applied onto the spinal cord or intravenously administered into the spinal cat, on average, about three quarters of the CPCA-induced inhibitory effect was abolished. On the other hand, in the animal with spinal lesions in the ipsilateral dorsolateral area, the CPCA-induced inhibition was comparable to that observed in the spinal cats. In conclusion, this study shows that adenosine agonists strongly suppress the responses of WDR cells to pinch, C fiber stimulation and thermal stimuli mainly through the supraspinal adenosine $A_2-receptors$.

• Journal of Acupuncture Research
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• 제38권4호
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• pp.300-311
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• 2021

Background: So far there is no confidence in the basics of acupoint/meridian phenomena, specifically in spatial and temporal electrical manifestations in the skin. Methods: Using the skin electrodynamic introscopy, the skin areas of 32 × 64 mm² were monitored for spectral electrical impedance landscape with spatial resolution of 1 mm, at 2 kHz and 1 MHz frequencies. The detailed baseline and 2D test-induced 2 kHz-impedance phase dynamics and the 4-parameter time plots of dozens of individual points in the St32-34 regions were examined in a healthy participant and a patient with mild gastritis. Non-thermal stimuli were used: (1) (for the sick subject), microwaves and ultraviolet radiation applied alternately from opposite directions of the meridian; and (2) (for the healthy one) microwaves to St17, and cathodic/anodic stimulation of the outermost St45, alternately. Results: In both cases, the following phenomena have been observed: emergence of in-phase and/or antiphase coherent structures, exceeding the acupoint conditional size of 1 cm; collective movement along the meridian; reversible with a reversed stimulus; counter-directional dynamics of both whole structures and adjacent points; local abnormalities in sensitivity and dynamics of the 1 MHz and 2 kHz parameters indicating existence of different waveguide paths. Conclusion: It is assumed that these findings necessitate reconsideration of some basic methodological issues regarding neurogenic/acupuncture points as spatial and temporal phenomena; this requires development of an appropriate approach for identifying the acuzones patterns. These findings may be used for developing new approaches to personalized/controlled therapy/treatment.

• Journal of Acupuncture Research
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• 제19권3호
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• pp.64-76
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• 2002

Objective : The purpose of this study is to investigate the mechanism and effect of moxibustion objectively and to be used as the quantitative data for developing the new thermal stimulating treatment by observing the combustion characteristics of commercial moxaes. Methods : We have selected two types(large-size moxa A(LMA), large-size moxa B(LMB)) among large moxaes used widely in the clinic. We examined combustion times, temperatures, temperature gradients in each period during a combustion of moxa. Results : 1. The ascending temperature gradient measured in the central point of non-contacted surface was fastest, the average ascending temperature gradient of both moxaes was $0.0384^{\circ}C/sec$, $0.0123^{\circ}C/sec$ respectively, 3.1 times faster in LMA. The maximum ascending temperature gradient was also about 2.9 times faster in LMA. The time required for the maximum ascending temperature gradient from ignition was 254sec, 411sec respectively. 2. The minimum descending temperature gradient in the retaining period was $-0.0250^{\circ}C/sec$, $-0.0090^{\circ}C/sec$ respectively and the average descending temperature gradient was $-0.0160^{\circ}C/sec$, $-0.0037^{\circ}C/sec$ respectively on the non-contact surface. 3. On the basis of the non-contact surface($A_I$), the time at which the effective stimulus period began to occur was about 264sec, 796sec respectively after an ignition, the time at which the maximum temperature began to occur was about 373sec, 1323sec respectively after an ignition, and the maximum temperature was $0.9^{\circ}C$ higher in LMA. The maximum ascending temperature gradient was also about 4.2 times faster in LMA. Conclusion : It was thought that not only the figure of moxicombustion device, but also the form and size of moxa had influence on the combustion characteristics deciding the performance of stimulus seriously.