• Journal of Pharmaceutical Investigation
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• v.39 no.1
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• pp.55-58
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• 2009

Sodium polyacrylate based hydrogel patch was prepared and its wound healing efficacy in comparison with control groups was evaluated in thermal burn wound ($200^{\circ}C$, 10 sec burn) and excision wound rat model. Cytotoxicity of gamma irradiated (25 kGy) hydrogel patch was investigated in human fibroblasts and showed no significant cytotoxicity. Wound closure rates (H50%) in hydrogel patch group and BAND-$AID^{(R)}$ treated group were faster than that of control group (uncovered open wound). Hydrogel patch showed an enhancement in wound healing process.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.28 no.1
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• pp.53-67
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• 2015

Objective: The aim of this study was to investigate the wound healing effect of herbal ointment, Gamijaungo, on the burn-induced model. Reports about Gamijaungo on the wound healing effect by local application in mice model or human study have published in the several domestic or internationally, but most are anecdotal and lack solid scientific evidence. Method: We observed the morphologic and histologic changes in the burn-induced mice model. we counted white blood cell and platelet changes. we confirmed VEGF, PI3K and pAkt protein expression by Western blot analysis. Result: In this study, we observed that Gamijaungo showed strong wound healing effects in the morphologic and histologic changes in the burn-induced mice model. Also we found that the significant changes of white blood cell and platelet changes by the treatment of Gamijaungo. In molecular mechanism, we got the strong positive effect by Gamijaungo treatment on angiogenesis, a key process in the formation of the granulation tissue during wound healing. Conclusion: These findings suggest the potential use of Gamijaungo as a therapeutic in thermal burn-induced skin injuries.

• Archives of Plastic Surgery
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• v.35 no.4
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• pp.373-378
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• 2008

Purpose: In full thickness burn, the depth of burn is known to increase until around 1-3 days after the burn. However, no study on how the depth increase during the first 24 hours has been conducted. Therefore, the authors investigated how the depth of burn changes within the first 24 hours after the burn by using the standardized burn model. Methods: A total of four experiments on pigs were carried out for this study. Experiment 1 was performed to examine how temperature affects the depth of burn. The digitally controlled aluminum thermal block was set at different temperatures-80, 90 and 100 degrees in Celsius, respectively. Then the pig was exposed to the block for 15 seconds each time. The time exposed to heat was set as a variable for the Experiment 2. The temperature was maintained at 80 degrees Celsius, and the pig was contacted with the thermal block for 5, 10 and 20 seconds, respectively. The biopsy of the tissues were performed in one hour, 6 hours, 24 hours, and 7 days after the burn. After hematoxylin and eosin staining a percentage of the depth from a basement membrane of epidermis to the deepest tissue damaged by the burn against total dermal thickness was measured. Results: In Experiment 1, the depth of burn increased considerably as time passed by. At all three temperatures, differences in depths measured in 6 and 24 hours, and in 1 hour and 7 days were both significant. In addition, the depth deepened as the temperature went higher. In the case of Experiment 2, the depth of burn also increased significantly as time passed by. At all three times, differences in depth measured in 6 and 24 hours, and in 1 hour and 7 days were also significant. Moreover, the depth extended with longer contact time when it was compared according to the time. Conclusion: Full thickness burn progressed rapidly from 6 to 24 hours after the burn and the depth of burn was almost decided within the first 24 hours after the burn. On the other hand, partial thickness burn also advanced from 6 to 24 hours after the burn but the depth deepened at slower level.

• YAKHAK HOEJI
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• v.48 no.1
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• pp.55-59
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• 2004

A PVA-soft hydrogel, which is a semi-solid form in container, whereas after applying on the skin, it formed a thin layer within a few minutes. In this study, we prepared a novel type PVA-soft hydrogel containing 6-methyluracil as active drug, and the therapeutic value was characterized. To evaluate the therapeutic value of the PVA-soft hydrogel containing drug, various animal models, thermal burn model, incision & excision wound rat model were used. We also measured the wound size and breaking strength to calculate the wound healing extent after single or multiple administration. The wound size of soft hydrogel treated group decreased rapidly than that of control group after multiple dosing in excision wound model. And, the breaking strength of the soft hydrogel treated group was greater than that of control group in incision wound model.

• Journal of Pharmaceutical Investigation
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• v.35 no.4
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• pp.255-263
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• 2005

Research was undertaken to compare the pharmacological activity of Lithospermi radix (LR) reported as an oriental medicine for classical uses. LR contains naphthoquinone pigments : shikonin, acetylshikonin, isobutylshikonin, etc. LR is used for the treatment of excision wound, burn, eczema, blister, scarlatina and septicemia as antifebrile, antidotic and antiphlogistic. Gardeniae fructus (GF) has been used for the treatment to jaundice, hepatic disease, anti-inflammatory and analgesic effects, and it contains crocin, geniposide and its derivatives. The therapeutic effects of burn and excision wound healing from LR & GF hydrogel with $Nano-ATP^{\circledR}$ (GLN) were investigated. To evaluate the therapeutic value of various hydrogels, thermal burn model and excision wound mouse model were used. The burn and wound reduction rate and therapeutic period were measured to calculate the healing extent after 5 experiments. The 2nd degree burn was prepared on hairless mouse back skin and dressing with collagen. The burn and wound reduction rate of GLN hydrogel treated group decreased more rapidly than that of other gel group in animal model. Furthermore therapeutic periods of GLN hydrogel treated group was shorter than that of other gel group. In anti-inflammatory test, GLN hydrogel treated group decreased edema rapidly than that of other gel group. These results suggest that the GLN hydrogel treatment has an therapeutic effect on burn and excision wound healing.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.1
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• pp.18-26
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• 1997

Grinding burn formed on the ground surface is related to the maximum temperature of workpiece surface and wheel tempertaure in the grinding process. The thermal characteristics of workpiece and grinding conditions on the surface tempertaure of the oxidation growing layer after get out of contact with the grinding wheel. The assumption used in grinding power signatures leads to the local temperature distribution between grinding wheel and workpiece, i.e., a single curve determines temperatures anywhere within the grinding wheel at anytime. This information is useful in the study of the grinding burn penetration into the wheel and thus provides an presentation of grinding trouble monitoring for the burning. On the basis of grinding power signatures in the wheel, thermally optimum grinding conditions are defined and controlled. To cope with grinding burn, the use of grinding power signatures is an effective monitoring systems when occurring the grinding process. In this paper, the identified parameters suggested in this study which are derived from the grinding power signatures are presented, and prediction model by grinding power utilized a linear regression algorithm is applied.

• Journal of Radiation Protection and Research
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• v.41 no.2
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• pp.155-159
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• 2016

Background: Nuclear reactors produce a great number of antielectron neutrinos mainly from beta-decay chains of fission products. Such neutrinos have energies mostly in MeV range. We are interested in neutrinos in a region of keV, since they may take part in special weak interactions. We calculate reactor antineutrino spectra especially in the low energy region. In this work we present neutrino spectrum from a typical pressurized water reactor (PWR) reactor core. Materials and Methods: To calculate neutrino spectra, we need information about all generated nuclides that emit neutrinos. They are mainly fission fragments, reaction products and trans-uranium nuclides that undergo negative beta decay. Information in relation to trans-uranium nuclide compositions and its evolution in time (burn-up process) were provided by a reactor code MVP-BURN. We used typical PWR parameter input for MVP-BURN code and assumed the reactor to be operated continuously for 1 year (12 months) in a steady thermal power (3.4 GWth). The PWR has three fuel compositions of 2.0, 3.5 and 4.1 wt% $^{235}U$ contents. For preliminary calculation we adopted a standard burn-up chain model provided by MVP-BURN. The chain model treated 21 heavy nuclides and 50 fission products. The MVB-BURN code utilized JENDL 3.3 as nuclear data library. Results and Discussion: We confirm that the antielectron neutrino flux in the low energy region increases with burn-up of nuclear fuel. The antielectron-neutrino spectrum in low energy region is influenced by beta emitter nuclides with low Q value in beta decay (e.g. $^{241}Pu$) which is influenced by burp-up level: Low energy antielectron-neutrino spectra or emission rates increase when beta emitters with low Q value in beta decay accumulate Conclusion: Our result shows the flux of low energy reactor neutrinos increases with burn-up of nuclear fuel.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.911-915
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• 2014

Pyrotechnic devices are widely used for space appendages. However, a cube satellite requirements do not permit the use of explosive pyrotechnic device. A nichrome burn wire release has typically been used for holding and release of deployable appendages of the cube satellite due to its simplicity and low cost. However, relatively low mechanical constraint force and system complexity for application of multi-deployable systems are disadvantages of the conventional mechanism. To overcome these drawbacks, we have developed a segmented nut type holding and release mechanism based on the nichrome burn wire release. The great advantages of the mechanism are much lower shock level and larger constraint force than the conventional mechanism using pyro. Flight model for on-orbit verification was developed and verified through release function test, vibration test and thermal vacuum test.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.2
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• pp.160-169
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• 1995

A mathematical model for the pyrolysis processes during unforced smoldering of cigarette was proposed in this study by analyzing the physical model of the smoldering cigarette (including the establishment of burning front between burning zone and pyrolysis zone, and analyzing the involvement of main factors such as pyrolysis of virgin tobacco, evaporation of water, and internal heat transport in the processes). Thermal conduction of cigarette paper and convective and radiative heat transfer at the outer surface were also considered via the thermal resistance law for the competitive heat transfer mechanisms. The governing partial differential equations were solved using an integral method. Model predictions of smoldering speed, or linear burn rate, as well as temperature and density profiles in the pyrolysis zone for different kinds of cigarettes were found to be close to the experimental data in the literature (Muramatsu, 1981). The model provides a relatively fast and efficient way to simulate the pyrolysis processes and offers a practical tool for exploring important parameters for a smoldering cigarette, such as blended tobacco composition, properties of cigarette paper, and heat flux from the burning zone to the pyrolysis zone.

• Medical Lasers
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• v.9 no.1
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• pp.51-57
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• 2020

Background and Objectives For experiments on simulated burn, the preparation of an animal model is a very important step. The purpose of the current experiment is to design a simple and controllable method for the preparation of third-degree scald in a mouse model using the boiling water method. Materials and Methods A total of 18 Swiss mice were used. After the anesthetization, the mice were scalded by boiling water (100℃) using a mold with a 1 cm² circle area on the dorsum at contact times of 3s, 5s, and 8s. After confirming that 8 seconds of scald can cause a third-degree scald, the skin samples were collected at day 2, 4, 6, 8, 10, and 12, and analyzed by histopathological examinations. The wound retraction index (WRI) was also measured. Results Third-degree scald involving full-thickness skin was observed in the 8-second scald group, while a 3-second scald caused a superficial second-degree scald and a 5-second scald caused a deep second-degree scald. After third-degree scald, the burn wound continued to contract until day 14. Conclusion The scalding model of mice can be successfully established by the boiling water method. This method is easy to operate, it has a low cost, and it can control the scald depth by controlling the scald time. This is adequate to study skin thermal injury in the future. The scald model established by this method can last for 14 days.