• 한국식품조리과학회지
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• 제21권5호
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• pp.703-708
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• 2005

The purposes of this study were to establish washing conditions for vegetable salad to reduce the microbial hazard by using sodium hypochlorite solution and eventually to implement HACCP for salad processing. By using the salad production line of Shinkeum Co. located in Gwacheon, Gyunggi-do, salad samples were washed under several washing conditions (chlorine dip period, chlorine concentration, rinse time, etc.) to determine the most effective conditions. The original washing line consisted of 3 baths (100 ppm chlorine water dip, water rinse, and water rinse), each with a capacity of 100 L of tap water and 5 kg of salad. First, the salad samples were washed with 100 ppm of sodium hypochlorite solution for various dip times (3, 6, 9, 12 min); however, only a 1 log- or less-reduction in total microbial counts was achieved in all groups and the time of chlorine water dip was not a significant factor in reducing the microbial hazard. When another water bath was added before the chlorine water dip (4-bath washing), a 2 log-reduction in total microbial counts was achieved. This result suggested the importance of pre-dipping salad materials in water before chlorine treatment to reduce the organic load on the surface of the vegetables. Coliforms were not detected at all after washing. As the concentration of chlorine $(50{\sim}150\;ppm)$ and rinse time $(0.5{\sim}2\;min)$ increased, greater microbial reduction was achieved; however, physical damage of the salad was observed. Finally, the optimum washing conditions for salad were determined as 3 min-water dip, 3 min-chlorine (100 ppm) dip, 2 min-rinse, and 2 min-rinse.

• Journal of Preventive Medicine and Public Health
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• 제21권2호
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• pp.238-244
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• 1988

This study was conducted to investigate the causes of burn and emergency cares taken on the spot for the burn patient. Study population included 161 burn patients admitted to 2 university hospitals and 1 general hospital in Taegu from November 1, 1987 to April 30, 1988. Patients or guardians were interviewed with a structured questionnare. Out of 161 burn patients 111(68.9%)were males and 50(31.1%) females. Preschool children of 1-4 years old accounted for 29.8% of the total patients. Burns of children under 15 years of age took place at home in 91.0%, while 48.3% of burns of adult (15 years and over)males occurred at the working place, and 68.0% of adult females occurred at the home. Out of total burns occurred at home 39.8% took place at kitchen/dining room and 24.1% in the room. The most common cause of burns in children was the boiling water or hot food (74.3%). In adults the common causes were electrical burn(22.4%), hot water or food(19.0%) and explosion(12.1%) for males, and hot water or food(32.0%) and explosion (20.0%) for females. Common emergency cares for the burn taken on the spot were undressing(64.6%), pouring Soju(liquor)(13.7%), and pouring cold water(5.0%). There were a few cases who applied ash, soy or salt. To prevent burn, it is recommended to remodel the traditional kitchen and coal-briquet hole, to strengthen the safety control of LP Gas and LN Gas supply, to educate the public for the handling method for such gases, to strengthen the occupational safety control, to improve the safety device for the electric wire and socket, and to limit the temperature of hot water at home and public baths.

• Advances in Traditional Medicine
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• 제7권3호
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• pp.211-216
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• 2007

Swollen and painful extremities have been treated with herbal baths in attempts to alleviate the symptoms. A popular herbal bath used in China, contains a component called 'bone-penetrating herb' which is believed to facilitate the penetration of herbal substances across the skin to the swollen site, so swollen site, so that pain and swelling will be improved. A search from the Chinese pharmacopedia revealed that 22 different herbs have been traditionally used as 'bone-penetrating herb'. Five of these herbs were available in market and were chosen for experimental studies. Standard diffusion experiments were done to identify the most effective herb among the five, in the penetration facilitation. Glechoma longituba at a concentration of 20% was found to give the best results in the facilitation of Bromophenol blue diffusion across artificial and biological membranes. When compared with one commonly used diffusion facilitator, viz. azone, azone was found to be more effective than glechoma longituba. The encouraging observations support future studies on the basic science behind the use of herbal components as topical agents to treat pain and swelling.

• 한국표면공학회지
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• 제1권1호
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• pp.5-13
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• 1967

Up to this date, numerous methods of analysis of electropling solutions are published. Some, however, need lots of works before reaching final results, or require high technique and special instruments, and also some are unaccurate due to unclearnes of end point. Like our undevelop countries, technicians of electroplating shops are most high school graduates or under, and have not much knowledge on chemistry. Furthermore, those technicians have to control their plating solutions by themselves without having enough analytical laboratory equipment . Therefore, in this paper the simplest, besides accurate method is investigated after comparing numerous methods published. Among the methods of copper determinations from acid and alkaline copper plating baths, EDTA titration method are chosen, due to these methods are the simpest and fastest for the evaluation of metal content, without requirng any special instrument. For acid copper solutions, chelate titrations were accurate enough. Since the end point of titration of chelate method is variable according to the kind of indicators and other metal's coexisitence as well as solution component, many difficulties were encountered from cyanide copper, on the contrary of acid copper bath. PAN , PV, and MX indicators were tried , but it is found that MX is the best. In chyanide solution ,due to cyanide is the masking reagent , elimination of this component is essential , and finally found that elimination CN-by precipitation with AgNO$_3$ solution was the simplest and the most accurate way among others. This method was very accurate for the new plating solutions even coexistence with organic brightners. However used solutions for long months running have to be predetermined the accurate copper value by thiosulfate method form time to time, before chelate titration by means of AgNO$_3$ precipitation. Always some constant deviations will be seen according to the solutions nature. Therefore those deviation values have to be compensated each time.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.96.2-96.2
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• 2017

This research was conducted to investigate the electrochemical properties of the thin air-formed oxide film-covered AZ31 Mg alloy. In this work, native air-formed oxide films on AZ31 Mg alloy samples were prepared by knife-abrading method and the changes in the electrochemical properties of the air-formed oxide film were investigated in seven different electrolytes containing the following anions $Cl^-$, $F^-$, $SO{_4}^{2-}$, $NO_3{^-}$, $CH_3COO^-$, $CO{_3}^{2-}$ and $PO{_4}^{3-}$. It was observed from open circuit potential (OCP) transients that the potential initially decreased before gradually increasing again in the solutions containing only $CO{_3}^{2-}$ or $PO{_4}^{3-}$ ions, indicating the dissolution or transformation of the native air-formed oxide film into new more protective surface films. The Nyquist plots obtained from electrochemical impedance spectroscopy (EIS) showed that there was growth of new surface films with immersion time on the air-formed oxide film-covered specimens in all the electrolytes; the least resistive surface films were formed in fluoride and sulphate baths whereas the most protective film was formed in phosphate bath. The potentiodynamic polarization curves illustrated that passive behaviour of AZ31 Mg alloy under anodic polarization appears only in $CO{_3}^{2-}$ or $PO{_4}^{3-}$ ions containing solutions and at more than $-0.4V_{Ag/AgCl}$ in $F^-$ ion containing solution.

• Molecules and Cells
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• 제23권2호
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• pp.175-181
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• 2007

The present study was undertaken to determine whether $SM22{\alpha}$ participates in the regulation of vascular smooth muscle contractility using $SM22{\alpha}$ knockout mice and, if so, to investigate the mechanisms involved. Aortic ring preparations were mounted and equilibrated in organ baths for 60 min before observing contractile responses to 50 mM KCl, and then exposed to contractile agents such as phenylephrine and phorbol ester. Measurement of isometric contractions using a computerized data acquisition system was combined with molecular or cellular experiments. Interestingly, the aortas from $SM22{\alpha}$-deficient mice ($SM22^{-/-LacZ}$) displayed an almost three-fold increase in the level of $SM22{\beta}$ protein compared to wild-type mice, but no change in the levels of caldesmon, actin, desmin or calponin. $Ca^{2+}$-independent contraction in response to phenylephrine or phorbol ester was significantly decreased in the $SM22{\alpha}$-deficient mice, whereas in the presence of $Ca^{2+}$ neither contraction nor subcellular translocation of myosin light chain kinase (MLCK) in response to phenylephrine or 50 mM KCl was significantly affected. A decrease in phosphorylation of extracellular signal regulated kinase (ERK) 1/2 was observed in the $SM22{\alpha}$-deficient mice and this may be related to the decreased vascular contractility. Taken together, this study provides evidence for a pivotal role of $SM22{\alpha}$ in the regulation of $Ca^{2+}$-independent vascular contractility.

• 한국표면공학회지
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• 제50권1호
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• pp.29-34
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• 2017

Chloride plating solution was fabricated by dissolving metal Ni powders in a mixed solution with HCl and de-ionized water. Effects of $Ni^{2+}$ and saccharin concentrations in the plating baths on current efficiency, residual stress, surface morphology and microstructure of Ni films were studied. In the case of $0.2M\;Ni^{2+}$ concentration, current efficiency was decreased to about 65 % with increasing saccharin concentration, but, in the case of $0.7M\;Ni^{2+}$ concentration, it was shown more than 90 % with the increase of saccharin concentration. Residual stress of Ni thin film was appeared to be about 400 MPa up to 0.0244 M saccharin concentration at the $0.2M\;Ni^{2+}$ concentration and surface morphology with severe cracks was observed in the range of 0.0487~0.0975 M saccharin concentration. Residual stress of Ni thin films was measured to be about 750 MPa without saccharin addition and 114~148 MPa at the range of 0.0097~0.0975 M saccharin concentration for the $0.7M\;Ni^{2+}$ concentration. Relatively low residual stress values (114~148 MPa) of the Ni films at the range of 0.0097~0.0975 M saccharin concentration may be resulted from codeposition of S from saccharin. Ni films at $0.7M\;Ni^{2+}$ concentration showed smooth surface morphology and were independent of saccharin concentration. Ni films at $0.7M\;Ni^{2+}$ concentration consist of FCC(111), FCC(200), FCC(220) and FCC(311) peaks and the intensities of FCC(111) and FCC(200) peaks increased with increasing saccharin concentration. Also, the average grain size decreased with increasing saccharin concentration from about 30 nm to about 15 nm.

• Restorative Dentistry and Endodontics
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• 제22권1호
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• pp.447-463
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• 1997

The purpose of this study was to evaluate the effectiveness of copal varnish and five bonding agents(Scotchbond Multi-Purpose Plus Dental Adhesive System, Panavia 21, All Bond 2, Superbond D-Liner II plus, Fuji Duet) in reducing microleakage under amalgam restorations. Class V cavity were prepared on both buccal and lingual surface of sixty extracted human molars with cementum margin and were filled with different kinds of liners and amalgam. All teeth were stored at $37^{\circ}C$ in physiologic saline solution. After 1 week they were thermally stressed for 500 cycles between 5 and $55^{\circ}C$ in baths containing 0.5 % basic fuchsin dye. The dye penetrations were observed with a stereomicroscope. Scanning electron micrographs were taken of representative tooth sections from each group to assess the nature of the tooth/liner/amalgam interface. The statistical test were applied to the results using a one way analysis variance (ANOVA) and Duncan's multiple range test. The results were as follows ; 1. In all groups, the enamel margin showed significantly lower leakage value than the cementum margin (p<0.05). 2. At the dentin and enamel margins, the leakage value of Copalite-lined group showed significantly higher than that of no liner group (p<0.05), but showed significantly lower than that of bonding agent lined-groups (p<0.05). 3. There was no significant difference between the bonding agent lined-groups (p>0.05). 4. On the backscattered scanning electron microscopy observation, discontinuous gaps were observed between amalgam and dentin in the bonding agent-lined amalgam restorations and the bonding agents appeared to fill the gap space and were mixed with amalgam particles. At the amalgam/tooth interface, unsealed dentin and continuous gaps were found in both unlined and Copalite-lined restorations.

• 대한한의학회지
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• 제19권2호
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• pp.228-243
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• 1998

This study was undertaken to evaluate the effect of Sunghyangchungisan (SHCS) on the regulation of vascular tone. Vascular rings isolated from rabbit carotid artery were myographed isometrically in isolated organ baths and the effect of SHCS on contractile activities were determined. SHCS relaxed the arterial rings which were pre-contracted by phenylephrine(PE). The responses to SHCS were partially dose-dependent at concentrations lower than 0.5 mg/ml. When SHCS was applied prior to the exposure to PE, it inhibited the PE-induced contraction by a similar magnitude which was comparable to the relaxation of pre-contracted arterial rings. Washout of SHCS after observing its relaxant effect resulted in a full recovery of PE-induced contractions, indicating that the action mechanism is reversible. The observation that SHCS did not change the $ED_{50}$ of PE on its dose-response curve ruled out the possible interaction of SHCS and ${\alpha}-receptor$. The relaxant effect of SHCS was not affected by removal of endothelium, and pretreatment of the arterial rings with methylene blue or nitro-L-arginine. This results suggest that the action of SHCS is not mediated by endothelium nor soluble guanylate cyclase. SHCS relaxed high $K^{+}-induced$ contractions as well, whereas it failed to relax phorbol ester-induced contractions. When contraction was induced by additive application of $Ca^{2+}$ in arterial rings which were pre-depolarized by high $K^+$ in a $Ca^{2+}-free$ solution, the relaxant effect of SHCS was attenuated by increasing the $Ca^{2+}$ concentration. SHCS, when applied to the arterial rings pre-contracted by PE and then relaxed by nifedipine, a $Ca^{2+}$ channel blocker, did not show additive relaxation. From above results, it is suggested that SHCS relax PE-induced contraction of rabbit carotid artery in an endothelium-independent manner, and inhibition of $Ca^{2+}$ influx may contribute to the underling mechanism.

• 대한한방부인과학회지
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• 제18권4호
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• pp.72-84
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• 2005

Purpose : This study was carried out to investigate the relaxational response to the water extract of Sobokchukeo-Tang(SCT) in isolated uterine muscle in rats. Methods : Segments of uterine muscle obtained from female rats immediately after delivery were mounted in organ baths superfused on a polygraph. The effects of SCT on the tension of potassium induced contracture were studied in rat uterine smooth muscles. All experiments were performed in Krebs-Henseit solution which was aerated with 100% oxygen and kept at $37^{\circ}C$. Results : KCI did not produce contraction in calcium-free solution, but $CaCl_2$ induced concentration-dependent contraction after depolarizing with KCI. SCT inhibited the tonic contraction of uterine muscle as dose dependent manner. And when SCT was pretreated in calcium-free medium, it showed more powerful relaxational effect. The effect of 10mg/ml concentration of SCT was equal to that of 9nM and 70nM of nifedipine and verapamil and the relaxational effect of SCT on rat uterine muscle can be assumed to be concerned with the action of cyclic AMP. But the action mechanism of relaxation on the rat uterine muscles were concerned with the calcium channel. Conclusion : From this study we could suggest that the relaxtional effect of SCT on uterine muscle be available to preventing and curing dysmenorrhea.