• Journal of Life Science
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• v.30 no.9
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• pp.743-748
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• 2020

Sulfate is a reductant that competes for electrons and may lower CH₄ production in the rumen. This study was designed to evaluate the beneficial effect of detoxified sulfur powder supplementation on in vitro rumen fermentation and methane mitigation. A ruminally cannulated Holstein Friesian cow was used as a rumen fluid source, and commercial pelleted concentrate was used as a substrate at 1 g dry matter. Treatments included the addition of detoxified sulfur powder at the rate of 0% (Control), 0.2% (T1), 0.4% (T2), 0.6% (T3), 0.8% (T4), and 1.0% (T5) as dry matter (DM) basis. The pH, total gas (TG), methane (CH₄) production, DM digestibility, organic matter (OM) digestibility, and volatile fatty acids (VFA) production were analyzed after 12 hr of incubation. The results showed that CH₄ production was significantly lowest in T1 (13.78 ml) but highest in the control (20.16 ml). Insignificantly higher total VFA was observed in control and T1 (64.99 and 64.28 mM, respectively) compared to other treatments after 12 hr of incubation. After 12 hr of incubation, the significantly lowest acetate:propionate was observed in T1 (1.90) while the highest was observed in T4 (2.44). However, no significant differences were recorded for pH, TG, DM digestibility, OM digestibility, acetate, propionate, and butyrate between the control and T1. Total number of bacterial DNA copies was significantly lower in the treatment group than the control. Therefore, it can be concluded from this study that detoxified sulfur at 0.2% inclusion level is optimal for production performance and ruminal CH₄ mitigation.

• Journal of dental hygiene science
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• v.6 no.3
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• pp.147-152
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• 2006

The purpose of this study was to help decrease turnover and to make full use of dental hygienists and to help improve management by managers. After relevant literature and data were reviewed, a survey was conducted on dental hygienists, who worked at dental institutes in different areas, for about four months from September through December, 2004, to find out their turnover intention and job satisfaction level. When the collected data were analyzed, the following findings were given: 1. The collective average of the dental hygienists investigated in job satisfaction was $3.30{\pm}0.70$. By area, they expressed the best satisfaction at a clear role factors with a mean of $3.53{\pm}0.73$, and they were pleased with wages factors and promotion factors the least with an average of $3.14{\pm}0.70$ and $3.18{\pm}0.80$. 2. The collective average of the dental hygienists investigated in turnover intention was $3.23{\pm}0.77$. As for connections between general characteristics and turnover intention, By age, those who aged in 21 and 25 were most intended(p < 0.001). The unmarried dental hygienists were more intended than the married ones(p < 0.001). By type of hospital, those who worked at dental clinics were most intended(p< 0.01). By career, those who had worked at one to three years were intended the most(p < 0.001), and as to the length of service at current work places, those who had worked at their current work places for one to three years were intended the most(p < 0.001). By monthly mean pay, those whose pay ranged from 1.3 to 1.6 million won found their turnover most intended(p< 0.01). 3. Regarding correlation among turnover intention and job satisfaction were both inversed correlationship, and wages factor(r = -0.249, p < 0.01) and interrelationship factors(r = -0.218, p < 0.01) had a strong correlation to turnover intention, and clear role factors had a strong correlation to job contents factors by job satisfaction(r = 0.612, p < 0.01), and job satisfaction factors had a strong correlation to job contents factors(r = 0.759, p < 0.01).

• Journal of dental hygiene science
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• v.6 no.3
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• pp.159-162
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• 2006

This study examined the relationship between the quantity of Streptococcus mutans and Lactobacillus spp. related to dental caries and the degree of acidity in saliva. A total of 240 saliva samples were taken from 80 subjects at the faculty of dentistry in Skopje, Macedonia. The saliva samples were taken by stimulating saliva production stimulation with paraffin chewing. However, no stimulation was applied when obtaining the samples used for measuring the pH. The data showed that in the caries group, S. mutans in 1 ml of saliva formed colonies with confluent growth (CFU > $10^6$ and $10^4-10^5$) in 100% of samples, whereas the Lactobacillus spp. formed colonies with confluent growth in 78.3%. In contrast, no colonies with confluent growth (CFU > $10^6$ and $10^5$) were found in the control group (with healthy intact teeth). In the caries group, the pH of the saliva was slightly acidic (pH = 5.90 - 6.50) and the buffering capacity was very low (below 0.7 ml of saliva per min). On the other hand, the pH of the saliva in the control group was neutral (pH 7.01 - 7.7) and the buffering capacity was high (over 1 ml of saliva per min). The increased number of S. mutans and Lactobacillus spp. in 1 ml of saliva (above $10^5$ CFU or more) from the CRT (Caries Risk Test, Vivadent, Liechtenstein) bacteria test can indicate an increased caries risk as well as slightly higher acidity of the saliva. Overall, these results reveal that the caries risk can be predicted by simply measuring the pH and buffering capacity of saliva, and can be used to monitor the effect of dental hygiene practices with the aim of preventing dental caries.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.342-347
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• 2012

This study is a temporary crowns and the period you want to avoid the exposure of the coffee girl polymerization types is difficult given the temporary tolerance by producing resin. 1. Change of brightness ($L^*$) edge in time increases, distilled water, Americano, Cafelatte, Vanillalatte was reduced to a significant level of brightness (p<.001). The most significant decrease in brightness of the Americano, which tend to grow out of a Cafelatte, Vanillalatte, which was followed by distilled water. 2. Change of redness ($a^*$) edge in time tend to increase saturation increases, the redness value of Americano, Cafelatte, redness value was a statistically significant difference in distilled water and Vanillalatte (p<.05) was not significant. 3. Change of yellowness ($b^*$) edge in time tend to increase saturation increases, the yellowness value of Cafelatte, Vanillalatte, Americano, except for distilled water at the saturation of yellowness value were no statistically significant (p<.05). 4. Change of color difference (${\Delta}E^*$) in order of (Americano>Cafelatte>Vanillalatte) as time of immersion increases change of color difference appear and no statistically significant (p<.05). Americano, the edge, since there can be more than chrominance is 3.3 uses station than a Vanillalatte, Cafelatte and discoloration when edge in 28, since even in the one to two difficult to distinguish with the naked eye as a discoloration. It was no difference statistically in color difference (${\Delta}E^*$) value in distilled water (p>.05).

• Journal of dental hygiene science
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• v.12 no.4
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• pp.392-403
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• 2012

This study aims at providing the basic data to help establish the right identity of dental hygienist and develop the work of dental hygienists, and thereby investigating the effect of patients' perception of dental hygienist on their social demand of dental hygienist, by conducting a survey of 300 patients visiting dentists around Busan-Gyeongnam region from April 7, 2012 to April 25, 2012. The collected data is statistically analyzed by SPSS (Statistical Packages for Social Science 14.0. SPSS Inc., Chicago, IL, USA). First, I analyzed the frequency by suggesting the demographic and descriptive characteristics of data, and conducted t-test and One-Way ANOVA at 5% of significance level to figure out the degree of perception and social demand of dental hygienists depending on customers' reason for visiting dentists, and also conducted regression analysis to find the effect of the perception of dental hygienist on patient's social demand of dental hygienist. The result suggests that as the perception of the dental hygienists' role, the social demand for dental hygienists' image increases, but as perception of dental hygienists' image increases, the social demand of dental hygienists' image decreases. Therefore, it suggests that as the knowledge about dental hygienists increases, patients demand their service more, while the perception of their image lowers the social demand for their image. It turns out that as the knowledge of dental hygienists increase, the social demand for the knowledge also increases.

• Journal of dental hygiene science
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• v.9 no.3
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• pp.319-326
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• 2009

The purpose of this study was to examine the Influence of the experience of Childcare Teacher about oral health education on oral health behaviors. For this, Questionnairs to be self-filled up about experience of oral health education were carried out to 267 childcare teachers who are working in nurseries in Geongnam province. The date was analysed using the SPSS 12.0 program. The obtained result were as follows. Among the respondents who are not under stress of oral health. 8.1% respondents had the oral health education and 7.7% others didn't have it. For toothbrushing methods, it was found that 25.3% used manual toothbrushing with experience in dental education(up and down toothbrushing monement) and 35.4% used semi automatic toothbrushing(rotational movement). 37.1% respondents had experiences in oral health education, 69.7% respondents were instructed in the oral health at public health center, and 61.6% respondents were instructed in the oral health a theory(toothbrushing guidance). Among the respondents who answered that oral health education should be necessary, 83.4% of those have already had oral health education where as 73.8% respondents have not had the education. 67.7% of the respondents who want to participate in the oral health education is corresponding to those with experience in dental education, 66.1% respondents with no education feel the necessity of the oral health education.

• Journal of Life Science
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• v.23 no.6
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• pp.757-769
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• 2013

A microorganism producing carboxymethylcellulase (CMCase) was isolated from seawater, identified as Bacillus velezensis by analyses of 16S rDNA and partial sequences of the gyrA, and designated as B. velezensis A-68. The optimal conditions for production of CMCase by B. velezensis A-68 were established using response surface methodology (RSM). The optimal concentrations of rice hulls and yeast extract, and initial pH of the medium for cell growth were 60.2 g/l, 7.38 g/l, and 7.18, respectively, whereas those for production of CMCase were 50.0 g/l, 5.00 g/l, and 7.30. The analysis of variance (ANOVA) implied that the most significant factor for cell growth as well as production of CMCase was yeast extract. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ in the medium for cell growth were 7.50, 1.00, 0.10, and 0.80 g/l, respectively, which were the same as those for production of CMCase. The optimal temperatures for cell growth and production of CMCase were 30 and $35^{\circ}C$, respectively. The maximal production of CMCase under optimized conditions was 83.8 U/ml, which was 3.3 times higher than that before optimization. In this study, rice hulls, agro-byproduct, were developed as a substrate for production of CMCase and time for production of CMCase was reduced to 3 days using a newly isolated marine bacterium.

• Analytical Science and Technology
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• v.27 no.1
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• pp.41-59
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• 2014

The aims of this work were the identification and the classification of fresh lubricants and used engine oils of vehicles for the application in forensic science field-80 kinds of fresh lubricants were purchased and 86 kinds of used engine oils were sampled from 24 kinds of diesel and gasoline vehicles with different driving conditions. The sample of lubricants and used engine oils were analyzed by GC/MS. The Bayesian model technique was developed for classification or identification. Both the wavelet fitting and the principal component analysis (PCA) techniques as a data dimension reduction were applied. In fresh lubricants classification, the rates of matching by Bayesian model technique with wavelet fitting and PCA were 97.5% and 96.7%, respectively. The Bayesian model technique with wavelet fitting was better to classify lubricants than it with PCA based on dimension reduction. And we selected the Bayesian model technique with wavelet fitting for classification of lubricants. The other experiment was the analysis of used engine oils which were collected from vehicles with the several mileage up to 5,000 km after replacing engine oil. The eighty six kinds of used engine oil sample with the mileage were collected. In vehicle classification (total 24 classes), the rate of matching by Bayesian model with wavelet fitting was 86.4%. However, in the vehicle's fuel type classification (whether it is gasoline vehicle or diesel vehicle, only total 2 classes), the rate of matching was 99.6%. In the used engine oil brands classification (total 6 classes), the rate of matching was 97.3%.

• Analytical Science and Technology
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• v.16 no.4
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• pp.283-291
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• 2003

Humic and fulvic acids present in soils of different depth were extracted and their acidic functional groups and structural characteristics were analyzed and compared. The purpose of this study was to present a basic data needed to evaluate the effect of humic substances on depth distribution and migrational behaviour of radioactive elements deposited on soil. Acidic functional groups of the humic and fulvic acids were analyzed by pH titration method, and their proton exchange capacity (PEC, $mq\;g^{-1}$) and average $pK_a$ values were obtained. Structural characteristics of the humic and fulvic acids were analyzed using their CPMAS $^{13}C$ NMR spectra and elemental composition data. pH titration data showed that fulvic acids have higher acidic functional group contents ranging from 5.5 to $7.0meq\;g^{-1}$ compared with that of humic acids ($3.8{\sim}4.8meq\;g^{-1}$). From depth profiles, it has been found that PEC values of humic acids in deeper soil (> 8 cm) were higher than those at the surface soils. Elemental compositions (H/C ratio) and spectral features ($C_{arom}/C_{aliph}$ ratio) obtained from CPMAS $^{13}C$ NMR spectra showed that the aromatic character in humic acids was a relatively higher than that of fulvic acids, while lower in carboxyl carbon content. The aromatic character and carboxyl carbon contents of humic acids tend to increase as soil depth increased, but those of fulvic acid showed little differences by the soil depth range.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.517-523
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• 2019

In this study, we investigated antioxidant capacity of 20 strawberry extract using the DPPH and ABTS assay and HPLC-DAD validation method. The total polyphenolic and flavonoids contents of 20 strawberry extracts were 22.77-107.61 mg TAE/100 g FW and 17.58-44.12 mg QE/100 g FW. The Aiberry and Elie star showed the highest total polyphenol and flavonoid contents, respectively. The DPPH radical scavenging activity of what was 1540.6-1124.0 μmol TEAC/100 g FW and Derunoka showed the highest activity. The ABTS radical scavenging activity was 6352.3-4592.3 μmol TEAC/100 g FW and FA23 showed the highest activity. The HPLC-DAD method for the quantitation of ellagic acid results showed high linearity in various concentration ranges, and the limit of detection was 2.35 μg/mL. The limit of quantification was 7.12 μg/mL. Relative standard deviation values from intra-and inter-day precision were less than 5.31%. Recovery rate at 10, 50, and 100 μg/mL, respectively, were 100.0-101.0% with relative standard deviation (RSD) values less than 5.30%. These results provide viable information for the validation of antioxidant capacity in strawberry fruits.