• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.6
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• pp.745-752
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• 2005

Green tea has various medical effects. It was selected as new natural dyes guessing the effects of the biological activities are still appeared on dyeing. It was examined whether they have the function of Uv-blocker or not. Cotton, linen & Hanji were dyed with Green tea. Al, Cr, Cu, Fe and Sn were selected as the mordant and the UV blocking rate of dyed samples was measured. The results of this study as follows; 1 . The color of dyed samples with Green tea changed yellowish red except Hanji and linen mordanted with Fe. 2. K/S values of dyed samples with Green tea increased by the number of dyeing treatment(p<.01). 3. UVA and UVB blocking rate increased by the number of dyes. Cotton and Linen could block the UV radiation over $93\%$ and Hanji could block over $95\%$ after three times of dyeing. These results suggest that Hanji has possibility far various practical uses of clothing material in beautiful and functional aspect. It could have the biological effects when we put on dyed clothing material with Green tea.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.456-461
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• 1996

Vascular relaxation action of crude extracts of two kinds of Coptidis rhizoma (Coptis chinensis and Coptis japonica, Ranunculaceae) was investigated and compared with that of berberine and palmatine, active alkaloid components of these plants. The results show that total extracts, berberine, and palmatine induced a concentration-dependent vasodilatation of rat thoracic aorta contracted with phenylephrine (PE). Palmatine, unlike to berberine, did not inhibit contraction induced by KCI. In calcium-free media, not only berberine but also crude extracts inhibited calcium-induced contraction. Furthermore, pretreatment of crude extracts inhibited contraction induced by PE noncompetitively. In PE-induced contraction, berberine was 2.5 times more potent than Coptis chinensis in the relaxation of rat aorta in terms of $IC_{50}$ values. Analysis of the effects of crude extracts on the Emax and $IC_{50}(PE)IC_{50}(KCI)$ ratios provides information on selectivity and indicates that extracts exhibit greater inhibition of the contrac tile response induced by PE than by KCI. We concluded that crude extracts have .alpha.-adrenoceptor blocking action and possesses inhibitory effect on calcium influx, which may be at least in part responsible for the antihypertensive action.

• The KIPS Transactions:PartC
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• v.10C no.4
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• pp.485-492
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• 2003

This paper presents a new modified input buffered switch, which called a grouped input buffered (GIB) switch, to eliminate the influence of HOL blocking when using multiple input buffers in ATM switches. The GIB switch consists of grouped sub switches per a network stage. The switch gives extra paths and buffered switching elements between groups for transferring the blocked cells. As the result, the proposed model can reduce the effect by the HOL blocking and thereafter it enhances the performance of the switch. The simulation results show that the proposed scheme has good performance in comparison with previous works by using the parameters such as throughput, cell loss, delay and system power.

• Safety and Health at Work
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• v.14 no.4
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• pp.457-466
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• 2023

Background: During hot environment work tasks with whole-body enclosed anti-bioaerosol suit, the combined effect of heavy sweating and exhaled hot humid air may cause the N95 medical respirator to saturate with water/sweat (i.e., water-blocking). Methods: 32 young male subjects with different body mass indexes (BMI) in whole-body protection (N95 medical respirator + one-piece protective suit + head covering + protective face screen + gloves + shoe covers) were asked to simulate waste collecting from each isolated room in a seven-story building at 27-28℃, and the weight, inhalation resistance (R_f), and aerosol penetration of the respirator before worn and after water-blocking were analyzed. Results: All subjects reported water-blocking asphyxia of the N95 respirators within 36-67 min of the task. When water-blocking occurred, the R_f and 10-200 nm total aerosol penetration (P_t) of the respirators reached up to 1270-1810 Pa and 17.3-23.3%, respectively, which were 10 and 8 times of that before wearing. The most penetration particle size of the respirators increased from 49-65 nm before worn to 115-154 nm under water-blocking condition, and the corresponding maximum size-dependent aerosol penetration increased from 2.5-3.5% to 20-27%. With the increase of BMI, the water-blocking occurrence time firstly increased then reduced, while the R_f, P_t, and absorbed water all increased significantly. Conclusions: This study reveals respirator water-blocking and its serious negative impacts on respiratory protection. When performing moderate-to-high-load tasks with whole-body protection in a hot environment, it is recommended that respirator be replaced with a new one at least every hour to avoid water-blocking asphyxia.

• Journal of Technologic Dentistry
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• v.32 no.4
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• pp.327-335
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• 2010

Purpose: The purpose of this study was to investigate the correlation between zirconia core thickness and color tone blocking of discolored tooth and metal post. Methods: For this study, we made 20-porcelain sample and 4-metal sample( liechtenstein IPS e.max) bonded to zirconia core of different thickness with cement(Relyx ARC-3M USA)for produce discolored. We measured the color-spectral characteristics, using Shadepilot equipment(Degudent USA).We measured it with Shadepilot equipment set by automated average mode in 3 times And applied the average value obtained from 2 times of measurement in the middle of each sample. Results: As a result of analysing color-spectral characteristics on zirconia core sample, Depending on the thickness of zirconia core, the value of brightness(${\Delta}L*$:color-spectral characteristic) was increased within limited range, value of ${\Delta}a*$, ${\Delta}b*$ was decrease. Conclusion: Consequently, we obtained the following results: Changes of sample color were observed depending on the thickness of zirconia, but the range of change did not exceed the scope range of shade guide. The case of metal posts, shade guide color D2 were observed in 0.5mm of zirconia core thickness. As a result, in case of porcelain, increasing the zirconia thickness of 0.3mm or more is unnecessary for color blocking effect, in case of metal post, considering the discolored tooth, thickness of zirconia with at least 0.5mm or more is recommended.

• Particle and aerosol research
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• v.18 no.4
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• pp.137-145
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• 2022

As many studies on the harmfulness of fine dust have been reported, awareness of its seriousness is spreading. Recently, interest in indoor air quality as well as air pollution is increasing, and research on measures to block fine dust flowing into the room from the outside is being conducted. The clothing company is launching functional clothing to prevent fine dust attached to clothing from entering the room through outdoor activities. However, it is difficult to confirm whether there is actually fine-dust blocking performance, and there is no evaluation standard. In this study, the contamination rate caused by fine dust was quantitatively compared through image processing after contamination of the outer fabric for 4 types of commercially available functional clothing with fine-dust blocking effect. The difference in particle contamination according to the material of the outer fabric was analyzed by comparing the surface resistance, and it was found that the higher the surface resistance of the outer fabric material, the more fine dust was attached. The analysis method of this study is expected to be able to quantitatively compare and evaluate the fine-dust blocking performance of functional clothing.

• Biomolecules & Therapeutics
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• v.31 no.2
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• pp.168-175
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• 2023

Tramadol is an opioid analog used to treat chronic and acute pain. Intradermal injections of tramadol at hundreds of millimoles have been shown to produce a local anesthetic effect. We used the whole-cell patch-clamp technique in this study to investigate whether tramadol blocks the sodium current in HEK293 cells, which stably express the pain threshold sodium channel Na_v1.7 or the cardiac sodium channel Na_v1.5. The half-maximal inhibitory concentration of tramadol was 0.73 mM for Na_v1.7 and 0.43 mM for Na_v1.5 at a holding potential of -100 mV. The blocking effects of tramadol were completely reversible. Tramadol shifted the steady-state inactivation curves of Na_v1.7 and Na_v1.5 toward hyperpolarization. Tramadol also slowed the recovery rate from the inactivation of Na_v1.7 and Na_v1.5 and induced stronger use-dependent inhibition. Because the mean plasma concentration of tramadol upon oral administration is lower than its mean blocking concentration of sodium channels in this study, it is unlikely that tramadol in plasma will have an analgesic effect by blocking Na_v1.7 or show cardiotoxicity by blocking Na_v1.5. However, tramadol could act as a local anesthetic when used at a concentration of several hundred millimoles by intradermal injection and as an antiarrhythmic when injected intravenously at a similar dose, as does lidocaine.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.3
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• pp.253-260
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• 2013

Purpose: To investigate the UV-B blocking rate of eyeglasses lens which can prevent enzymes denaturation in cornea. Methods: The denaturation degree of RNase A and catalase, superoxide dismutase (SOD) was determined by using Acrylamide gel electrophoresis after UV-B irradiation of 312 nm for 1, 3, 6, 24 and 96 hours. Also, the inhibitory effect of eyeglasses lens having UV-B blocking rate of 50%, 80%, 95% and 99% on the enzymes denatration was measured. Results: The denaturation of RNase A was induced by 1 hour-irradiation of UV-B. To inhibit RNase A denaturation after UV-B irradiation between 1 hour and 6 hours, UV-B blocking lens of 95% were effective. UV-B blocking lens of 99% suppressed the inhibition of RNase A denaturation after the UV-B exposure between 24 hours and 96 hours. The denaturation of catalase was not induced by 1 hourirradiation of UV-B. To inhibit enzyme denaturation after UV-B irradiation between 1 hour and 6 hours, UV-B blocking lens of 50% were effective. UV-B blocking lens of 95% suppressed the inhibition of enzyme denaturation induced by UV-B irradiation between 24 hours and 96 hours. The SOD denaturation was not induced by UV-B irradiation shorter than 6 hours exposure. The UV-B blocking lens of 50% could inhibit SOD denaturation after the UV-B irradiation for 24 hours. When SOD was exposed to UV-B for 96 hrs, SOD denaturation was inhibited by eyeglasses lens with UV blocking rate higher than 95%. Conclusions: The results demonstrated that the proper UV-B blocking rates of eyeglasses lens to inhibit the enzymes denaturatioin was different according to the types of enzymes and its inhibitory effect was effective only when eyeglasses lens had higher than certain UV-B blocking rate.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.3
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• pp.67-73
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• 2016

The present study evaluated the blocking effect of natural and artificial topography on sunshine duration in the southern coastal area of Haui-do. The geospatial data for the target area was constructed by geographic information system(GIS) data. Three-dimensional modeling based on solar azimuth and altitude angles was conducted for the assessment of sunshine environment. The sunshine area was evaluated over 80~90% of the target area in the daytime, especially in summer. The blocking effect of mountainous terrain on sunshine duration was presented at the northern residential area in the late afternoon. There was also the effect of artificial topography by construction of fill-up bank on sunshine environment at the southern residential area early in the morning and the south-western part of salt field in the late afternoon.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.1
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• pp.9-15
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• 2007

The aim of this study was to find the proper UV-A blocking percentage that could protect the denaturation of ribonuclease A (RNase A), one of protein enzymes in eye, induced by UV-A. RNase A was irradiated at 365 nm for 1, 3, 6, 24, 48, 72, 96 hr and the extent of denaturation was monitored by polyacrylamide gel electrophoresis. Furthermore, it was investigated whether blocking of UV-A by 20, 50, 80 and 99% eyeglass lens could protect the denaturation of RNase A or not. The denaturation of RNase A was induced by only 1 hr UV-A irradiation and the extent of denaturation became severe depending on UV-A irradiation time. The mild denaturation of RNase A induced by irradiation for 1 hr could be sufficiently protected by 20% UV-A blocking lens. When RNase A was irradiated for 3 hr, more that 50% blocking of UV-A needed to prevent the denaturation. Even though 99% UV-A blocking lens was used, the denaturation of RNase A induced by 6 hr irradiation could not be prevented perfectly. However, 99% UV-A blocking lens could dramatically decrease the severe denaturation of RNase A induced by irradiation for 96 hr.