• CELLMED
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• v.5 no.1
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• pp.5.1-5.5
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• 2015

In this first double-blind-placebo-controlled investigation of the Aeon Patch, electrocardiographic data were acquired from 50 well-hydrated volunteers [21 females and 29 males, age: 19-79, weight: 117-334 lbs, height: 5'-6',3"], under 3 different conditions for a total duration of 15 min (5 min/condition). Condition1: Control (C) - while wearing no Patch, Condition 2: Placebo (P) or Active (A) - after wearing either the Placebo or the Aeon Patch for 20 min, and Condition 3: Active (A) or Placebo (P) - after wearing either the Aeon or the Placebo Patch for 20 min. There was a washout period of 15 min between Conditions 2 and 3. All involved in the investigation were blind to the (A) and (P) Patches as they looked exactly the same and were assigned in a random fashion. The hypothesis to be tested was: Wearing the Aeon Patch for 20 min reduces stress. Data were first quality assured and those subjects who showed a parasympathetic response after wearing the Patch within 20 min were identified as early responders. Thirty subjects (60%) achieved a relaxed state after wearing the Aeon Patch as early as 20 min. Statistical analysis (one-sample inference) was used to compare the spectral features of the responders. The normalized LF/HF decreased significantly ($24%{\pm}9%$ after 20 min) in condition (A) compared to condition (P) with a p-value < 0.047 (n = 30) in responders. Therefore, the hypothesis that wearing the Aeon Patch for 20 min reduces stress was accepted as true.

• Reproductive and Developmental Biology
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• v.29 no.2
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• pp.117-120
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• 2005

This study was conducted to establish the optimal temperature condition before oocyte activation in B6m F1 mouse. In experiment 1, two embryo culture media (CZB vs KSOM) were evaluated for the development of activated mouse oocytes. Parthenogenetic embryos cultured in KSOM showed better blastocyst development than ones cultured in CZB $(56.2\%\;vs\;81.0\%\;p<0.01)$. Two-hour of pre-incubation before activation significantly reduced the number of hatched blastocysts in KSOM $(22.0\%\;versus\;8.8\%\;p<0.05)$. In experiment 2, recovered oocytes were pre-incubated at different temperature conditions before activation. The experimental groups were divided by 5 as follows. Group A: pre-incubation for 120 min at $37^{\circ}C$, Group B: pre-incubation at $37^{\circ}C$ for 90 min then at $25^{\circ}C$ for 30 min, Group C: pre-incubation at $37^{\circ}C$ for 60 min then at $25^{\circ}C$for 60 min, Group D: pre-incubation at $37^{\circ}C$ for 30 min then at $25^{\circ}C$ for 90 min, and Group E: pre-incubation at $25^{\circ}C$ for 120 min before activation. Group A $(67.6\%)$ and B $(66.7\%)$ showed better development to the blastocyst stage than other groups $(Group\;C:\;50.0\%\;Group \;D:\;49.2\%\;Group\;E:\;33.3\%,\;p<0.05)$. The present study indicates that the temperature before activation affects the development of B6D2 F1 mouse parthenogenetic oocytes and exposure to room temperature should be limited to 30-min when the oocytes are left in HEPES-buffered medium for micromanipulation.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.4
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• pp.51-56
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• 2012

In order to fabricate through-Si-vias for thermal vias by using wet etching process, anisotropic etching behavior of Si substrate was investigated as functions of concentration and temperature of TMAH solution in this study. The etching rate of 5 wt%, 10 wt%, and 25 wt% TMAH solutions, of which temperature was maintained at $80^{\circ}C$, was $0.76{\mu}m/min$, $0.75{\mu}m/min$, and $0.30{\mu}m/min$, respectively. With changing the temperature of 10 wt% TMAH solution to $20^{\circ}C$ and $50^{\circ}C$, the etching rate was reduced to $0.067{\mu}m/min$ and $0.233{\mu}m/min$, respectively. Through-Si-vias of $500{\mu}m$-depth could be fabricated by etching a Si substrate for 5 hours in 10 wt% TMAH solution at $80^{\circ}C$ after forming same via-pattern on each side of the Si substrate.

• The Korean Journal of Community Living Science
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• v.27 no.3
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• pp.419-435
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• 2016

The purpose of the present study was to suggest the design requirements for Korean naval duty uniforms by evaluating the physiological and psychological comfort while wearing the uniforms. Two sets of wear trials were conducted with summer uniforms(eight young males) and winter uniforms(seven other young males). The summer wear trial consisted of 10-min rest, 60-min exercise, and 10-min recovery at an air temperature($T_{air} $) of $33^{\circ}C$ and 62%RH, followed by 10-min recovery at a $T_{air} $ of $23^{\circ}C$ and 64%RH(total 90 min). The winter wear trial consisted of 20-min rest at $T_{air} $ $20^{\circ}C$ and 55%RH, 25-min rest, 30-min exercise, and 35-min recovery at a $T_{air} $ of 0oC and 43%RH(total 110 min). Rectal and seven skin temperatures, clothing microclimate, heart rate, oxygen consumption, total sweat rate, and subjective perceptions were measured during the wear trials. By evaluating the experimental results from the wear trials, we extracted the following psycho-physiological design requirements to improve the current Korean naval uniforms: (1) It is important to maintain the skin temperatures within their comfort range, which depends on the body region (higher than $30^{\circ}C$ in winter, but less than $35^{\circ}C$ in summer). (2) In summer, the feet should be protected from the high heat of the ship floor surface. (3) In summer, sweat from the back should be sufficiently absorbed and allowed to dry quickly.

• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.133-141
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• 1994

Optimal thawing conditions of frozen model foods containing protein and starch were nvestigated at various thawing conditions such as room temperature, hot air, and microwave heating. Hardness of the frozen model foods was getting higher as the water content increased. Thawing rates at room temperature, hot-air heating at $50^{\circ}C$, and microwave heating were 0.02 Kg/min, 0.08 Kg/min, 0.01 Kg/min, respectively. Final thawing time was as follows; control 60min, 5% sucrose: 50 min, 10% sucrose: 30 min, 5% NaCl: 30 min. Total drip loss was as follows; room temperature thawing: 22.5%, 200W microwave thawing 1.3%, and $50^{\circ}C$ hot air thawing nearly negligible.

• Restorative Dentistry and Endodontics
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• v.15 no.2
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• pp.93-103
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• 1990

The primary purpose of this study was to assess the effect of the EDTA on human dentin hardness of root. The 30 extracted human anterior teeth were divided into three groups, and EDTA was applied on the each tooth root dentin surface for 5, 15 and 30 minutes to evaluate the dentin hardness. The following results were obtained : 1. The KHN of dentin was decreased by 21.3% from 50.8 to 40.0 in 5 min. group, 44.2% from 48.4 to 27.0 in 15 min. group, and 51.9% from 48.0 to 23.1 in 30 min group. 2. The decrease rate per 1 min. of KHN of dentin was 4.3 in 5 min. group, 2.9 in 15 min. group, and 1.7 in 30 min. group. 3. As time passed, the KHN of dentin of 5 min. group and 15 mim. group were significantly decreased, but the KHN of dentin of 30 min. was not significantly decreased compared with 15 min. group. There was a statistical significance in the decrease rate of KHN of dentin among 3 groups(P<0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.6
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• pp.767-775
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• 1999

The purpose of this study was to evaluate the effect of wattage and curing time on surface hard-ness, three-point bending strength and internal porosity of microwave curing denture base resin. Two sizes of resin specimens were made of Acron $MC^{(R)}\;;\;3.5{\times}10{\times}60mm$ for surface hardness and three-point bending strength measurement and $5{\times}12{\times}60mm$ for internal porosity measurement. They were cured by microwave energy at varing wattages(500W, 700W) and curing times(2min., 3min., 4min.) to determine if a certain wattage/curing time combination would improve physical properties. Surface hardness was measured with Vikers hardness tester, three-point bend-ing strength with universal testing machine and internal porosity was calculated by measuring the weight in air and in water. The results obtained were as follows: 1. There was no significant difference in percent porosity among experimental groups(p>0.05). 2. 500W/3min. group showed the higher surface hardness than 700W/2, 3, 4min. groups(p<0.05), and 700W/4 min. group showed the lower surface hardness than 500W/2, 3, 4min. groups(p<0.05), but there was no significant difference among others(p>0.05). 3. 500W/3min. group yielded the higher value of bending strength than 500W/2min., 700W/3, 4min. groups(p<0.05), but there was no significant difference among others(p>0.05).

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.331-337
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• 1994

In order to develop a $^{18}F$-labelled myocardial perfusion agent(flow tracer) for PET, $^{18}F$-labelled organic ammonium cations were synthesized and evaluated in relation to their biodistribution. Five quaternary organic ammonium compounds were labelled with $^{18}F$ in a side chain with moderate to good yields by direct introduction of $^{18}F$-fluoride. Radiochemical yields have been achieved in 30-40min by the precursors (tosylates) in dimethylsulfoxide 15-60% (decay corrected). The reaction was found to be autocatalyzed. A remote controlled procedure was developed in these synthesis. $^{18}F$-Labelling and HPLC-purification of com-pounds needed about 60 min(Yield; 7-20%). Up to now the two compounds N-4-[$^{18}F$]fluorobutyl-pyridinium cation(1) and N, N dibenzyl-4(2-[$^{18}F$]fluoroethyl)piperidinium cation(2) were investigated in relation to their biodistribution in mice. Compound 1 showed at 1 min post injection the high uptake of 19.22% ID/g organ in the myocardium but a following fast decline to 1.12% ID/g organ after 40min. Uptake of compound 2 was after 1min in the heart 5.90% ID/g organ but after 40min at the relative high value of 4.33% ID/g organ. Heart:blood ratio for compound(1) at 1 min was 8.3, at 40 min 2.6 for compound II 2.0(1min) and 15.0(40 min). As data of compound 2 showed greater heart uptake, slower myocardial release, and higher heart: blood ratios, compound 2 is a good candidate for further evaluation.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.3
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• pp.355-362
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• 2020

The corrosion behavior of the Inconel X-750 alloy was investigated for its potential application under a Cl₂-O₂ mixed gas flow in an Ar atmosphere. The corrosion rate was found to be negligible at temperatures up to 400℃ under a flow rate of 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar, whereas an exponential increase was observed in the corrosion rate at temperatures greater than 500℃. The suppression of the corrosion reaction due to the presence of O₂ was verified experimentally at flow rates of 30 mL·min^-1 Cl₂ (4.96 g·m^-2·h^-1), 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ (2.02 g·m^-2 ·h^-1), and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ (1.34 g·m^-2·h^-1) under a constant Ar flow rate of 170 mL·min^-1 at 600℃ for 8 h. The surface morphology analysis results revealed that porous surfaces with tunnel-type holes were produced under the Cl₂-O₂ mixed-gas condition. Furthermore, the effects of the Cl₂ flow rate on the corrosion rate were investigated, indicating that its impact was negligible within the range of 5-30 mL·min^-1 Cl₂ at 600℃.

• Journal of Welding and Joining
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• v.15 no.5
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• pp.56-63
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• 1997

In The study, the bonding of WC-9%Co to SUJ2 steel using Ag-Cu-Zn-Cd insert metal has performed to investigate the bonding properties by heat-treatment. Bonding was brazed for 5-30min at 95$0^{\circ}C$, performed solution treatment for 5 min at 85$0^{\circ}C$ and sustained subsequently oil quenching. To investigate the effect of heat-treatment, tempering was executed at $600^{\circ}C$ for 30 min after oil quenching. Mechnical properties and chemical compositions on the brazed bonding interface were investigated by means of microstructural observation, 4-point bending test and EDS and XRD measurements. The results obtained were as follows. 1) The bonding strength of WC-9%Co/SUJ2 joints by Ag-Cu-Zn-Cd insert metal obtained about 78, 117 and 72MPa after brazing for 5, 20 and 30 min at 95$0^{\circ}C$. And the highest bonding strength obtained about 131MPa after brazing for10 min at 95$0^{\circ}C$ 2) Higher bonding strength of 288MPa was obtained in the joint that brazed for 10 min at 95$0^{\circ}C$, and carried out tempering for 30 min at $600^{\circ}C$ subsequently. 3) Fracture of joint brazed by Ag-Cu-Zn-Cd insert metal for 5, 10, 20 and 30 min created WC-9%Co/SUJ2 interface. The joint that brazed for 10 min at 95$0^{\circ}C$ and then tempered for 30 min at $600^{\circ}C$ was fractured at the site of WC-9%Co.