• Magazine of the Korea Concrete Institute
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• 제9권3호
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• pp.127-135
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• 1997

In this study, the wedge splitting tcst (WST) was carried out for the fatigue wack growth behavior of concrete. Selected test variables were concrete compressive strength of 28, 60 and 118 MI%, and stress ratio with 2 levels (6. 13%). In oder to make the designed stress ratio, the maximum and thr minimum fatigue loading level were 75-85% and 5- 10% of ultimate static load, respectively. Fatigue testing was preceded by crack mout.h opening displacement (CMOI)) compliance calibration tcst, and then the fatigue crack growth was computed by crack lcngth vs. (lMOI) compliance relations acquisited by the CMOD compliance calibration technique. To evaluate thc validity of CMOD compliancc calibration techniquc, the crack length p~mlicted by this method was cornpard with the crack length by linear elastic fracture mechanics(LEFIbl) and dyeing test. On the basis of the experimental results, a LRFhl-based c.mpirica1 model for f'at,igue crack growth rate(da/dN-AKI relationships) was presented. The fat,igut. crack growth ratc increased with the strength of concwtc. It appcars that t.he da/tiN-AKI relationships was influenced by stress ratio, however, the effect is diminished with an increase of strength. The comparisons between CblOl) compliance calibration technique anti the other. methods gave the validity of' ('MOD compliance calibration technique for the LZXT.

• The Journal of the Korean dental association
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• 제55권8호
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• pp.516-526
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• 2017

Objective: To suggest diagnostic reference levels (DRLs) for dental panoramic radiography in adults and children through the nationwide survey in Korea. Materials and Methods: Two hundred twelve dental institutions on a national basis were visited. The radiographic examination protocols were surveyed and their patient doses at the clinical exposure setting for adult and children (5- and 10-year old) were measured at 244 panoramic radiographic equipment. The measured DAP were analyzed and compared according to age group, the size of hospital, the type of radiographic system, the installation duration of equipment. Results: The mean exposure parameters were 70.1 kV, 9.2 mA, 14.4 second for adult and 66.6 kV, 7.9 mA, 13.8 second for 10-year old child and 65.5 kV, 7.3 mA, 13.7 second for 5-year old child. The mean and third quartile patient DAPs were $138.3mGy\;cm^2$ and $151.0mGy\;cm^2$ for adult, $99.5mGy\;cm^2$ and $104.8mGy\;cm^2$ for 10-year old child and $89.5mGy\;cm^2$ and $95.5mGy\;cm^2$ for 5-year old child. The mean patient dose at the university dental hospital was lower than that at the dental clinic (p<0.05). The mean patient dose of direct digital radiography type was higher than that of film-based type. However, the difference did not show statistically significance. Conclusion: DRLs for dental panoramic radiography in adult, 10- and 5-year old child were suggested to be $151mGy\;cm^2$, $105mGy\;cm^2$, and $96mGy\;cm^2$ in Korea based on this nationwide survey.

• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6363-6367
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• 2014

Purpose: This study was conducted to assess the preventive effect of Actinidia valvata Dunn (AVD) extract on an animal model of gastrointestinal carcinogenesis on the basis of changes in tumor incidence, cell proliferation, and apoptosis. Materials and Methods: Seventy-five male Wistar rats were divided into five different treatment groups with 15 rats in each group. Group I was given normal feed, whereas Groups II to IV were treated with 10% sodium chloride in the first six weeks and 100ug/mL of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in drinking water for 24 weeks. Group II was then given normal feed, whereas Group III was given AVD extract (0.24g/kg/day) for 12 weeks. Group IV was given AVD extract from the first week to the 36th week, whereas Group V was treated with AVD extract alone for 36 weeks. All rats were sacrificed at the end of the 36-week experiment and assessed for the presence of gastrointestinal tumors. The occurrence of cancer was evaluated by histology. Bax, Bcl-2, Caspase-3, and cyclinD1 were determined by immunohistochemical staining and Western blotting. Results: The incidences of gastric cancer were 0% in Group I, 73.3% in Group II, 33.3% in Group III, 26.7% in Group IV, and 0% in Group V. Bcl-2 and cyclinD1 expression was decreased in AVD extract treated groups, whereas Bax and Caspase-3 expression was increased. Comparison with group II revealed significant differences (p<0.01). Conclusions: AVD extract exhibits an obvious preventive effect on gastrointestinal carcinogenesis induced by MNNG in rats through the regulation of cell proliferation and apoptosis.

• Progress in Medical Physics
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• 제27권4호
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• pp.203-212
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• 2016

Dose differences between three-dimensional (3D) and four-dimensional (4D) doses could be varied according to the geometrical relationship between a planning target volume (PTV) and an organ at risk (OAR). The purpose of this study is to evaluate the correlation between the overlap volume histogram (OVH), which quantitatively shows the geometrical relationship between the PTV and OAR, and the dose differences. 4D computed tomography (4DCT) images were acquired for 10 liver cancer patients. Internal target volume-based treatment planning was performed. A 3D dose was calculated on a reference phase (end-exhalation). A 4D dose was accumulated using deformation vector fields between the reference and other phase images of 4DCT from deformable image registration, and dose differences between the 3D and 4D doses were calculated. An OVH between the PTV and selected OAR (duodenum) was calculated and quantified on the basis of specific overlap volumes that corresponded to 10%, 20%, 30%, 40%, and 50% of the OAR volume overlapped with the expanded PTV. Statistical analysis was performed to verify the correlation with the OVH and dose difference for the OAR. The minimum mean dose difference was 0.50 Gy from case 3, and the maximum mean dose difference was 4.96 Gy from case 2. The calculated range of the correlation coefficients between the OVH and dose difference was from -0.720 to -0.712, and the R-square range for regression analysis was from 0.506 to 0.518 (p-value <0.05). However, when the 10% overlap volume was applied in the six cases that had OVH value ${\leq}2$, the average percent mean dose differences were $34.80{\pm}12.42%$. Cases with quantified OVH values of 2 or more had mean dose differences of $29.16{\pm}11.36%$. In conclusion, no significant statistical correlation was found between the OVH and dose differences. However, it was confirmed that a higher difference between the 3D and 4D doses could occur in cases that have smaller OVH value.

• Asian-Australasian Journal of Animal Sciences
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• 제31권10호
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• pp.1565-1574
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• 2018

Objective: The aim of the present study was to identify genetic variants based on RNA-seq data, obtained via transcriptome sequencing of muscle tissue of pigs differing in muscle histological structure, and to verify the variants' effect on histological microstructure and production traits in a larger pig population. Methods: RNA-seq data was used to identify the panel of single nucleotide polymorphisms (SNPs) significantly related with percentage and diameter of each fiber type (I, IIA, IIB). Detected polymorphisms were mapped to quantitative trait loci (QTLs) regions. Next, the association study was performed on 944 animals representing five breeds (Landrace, Large White, Pietrain, Duroc, and native Puławska breed) in order to evaluate the relationship of selected SNPs and histological characteristics, meat quality and carcasses traits. Results: Mapping of detected genetic variants to QTL regions showed that chromosome 14 was the most overrepresented with the identification of four QTLs related to percentage of fiber types I and IIA. The association study performed on a 293 longissimus muscle samples confirmed a significant positive effect of transforming acidic coiled-coil-containing protein 2 (TACC2) polymorphisms on fiber diameter, while SNP within forkhead box O1 (FOXO1) locus was associated with decrease of diameter of fiber types IIA and IIB. Moreover, subsequent general linear model analysis showed significant relationship of FOXO1, delta 4-desaturase, sphingolipid 1 (DEGS1), and troponin T2 (TNNT2) genes with loin 'eye' area, FOXO1 with loin weight, as well as FOXO1 and TACC2 with lean meat percentage. Furthermore, the intramuscular fat content was positively associated (p<0.01) with occurrence of polymorphisms within DEGS1, TNNT2 genes and negatively with occurrence of TACC2 polymorphism. Conclusion: This study's results indicate that the SNP calling analysis based on RNA-seq data can be used to search candidate genes and establish the genetic basis of phenotypic traits. The presented results can be used for future studies evaluating the use of selected SNPs as genetic markers related to muscle histological profile and production traits in pig breeding.

• Journal of the Korea Organic Resources Recycling Association
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• 제8권4호
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• pp.100-110
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• 2000

Studies were conducted to know effects of the bulking agents (saw dusts, mushroom waste, wheat bran coconut meal, rice hulls) adding o moisture control, fermentation methods (aerobic and anaerobic) and periods (1 to 20 days) of food waste fermentation for animal feeds on chemical compositions and in vitro DDM (digestibility of dry matter). Experiment designs were focussed basically to obtain extension service data. The NDF (neutral detergent fiber) composition in the oak and pine saw dust were 93.5% and 95.4% (DM basis) in respectively. Thus, the fermented food waste feeds using saw dust (50%) increased NDF(12%), and decreased in vitro DDM(48%) compared to those of raw materials before aerobic fermentation. The oak saw dust showed higher DDM compared to pine. Mushroom wastes which is a residues of mushroom culture mixed originally willow saw dust (80%) and wheat bran (20%) showed quite higher feed value compared to both saw dusts. It was found that an in vitro DDM and NDF composition in fermented feeds appeared highly dependent or the NDF composition in bulking agents. With an increase wheat bran ratio substitute mushroom waste showed linearly decreased NDF, and increased in vitro DDM in the fermented food waste feeds. The fermented feeds added bottling agents composed higher NDF resulted in higher NDF and lower in vitro DDM with prolonged fermentation time. The feeds from anaerobic fermentation appeared lower NDF and higher in vitro DDM compared to those of aerobic fermentation.

• Journal of Korean Society of Forest Science
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• 제83권3호
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• pp.380-390
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• 1994

This study was conducted to investigate the effects of the topographical factors (16 items), physico-chemical properties of soil (13 items) and meteorological factors(9 items) on the height growth of Pinus thunbergii stands along the coastal area in Korea. According to the coefficients by partial correlation analysis in total area, it was found that tree height growth was considerably affected by local topography, soil hardness, soil B-horizental depth, effective soil depth, soil moisture, parent rock, soil texture, and etc.. And the soil factors were available $P_2O_5$, total nitrogen, base saturation, exchangeable $Ca^{{+}+}$, and etc.. In partial correlation analysis, annual relative humidity, annual precipitation, index of aridity, and etc. were found to be the most important factors influencing on tree height growth of Pinus thunbergii stands. In conlusion, the topographical, soil and meteorological factors have multiplex influence on the tree height growth in the Pinus thunbergii stands. They promise to provide the basis of improving not only the selection of suitable sites and the management of soil fertilizer but also the estimation of growth and yield. Hence these results would be used successfully for the design in the scientific forest working plan.

• Asian-Australasian Journal of Animal Sciences
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• 제33권1호
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• pp.100-110
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• 2020

Objective: The objective of this study was to isolate proteolytic microorganisms and evaluate their effects on proteolysis in total mixed ration (TMR) silages of soybean curd residue. Methods: TMRs were formulated with soybean curd residue, alfalfa or Leymus chinensis hay, corn meal, soybean meal, a vitamin-mineral supplement, and salt in a ratio of 25.0: 40.0:30.0:4.0:0.5:0.5, respectively, on a basis of dry matter. The microbial proteinases during ensiling were characterized, the dominate strains associated with proteolysis were identified, and their enzymatic characterization were evaluated in alfalfa (A-TMR) and Leymus chinensis (L-TMR) TMR silages containing soybean curd residue. Results: Both A-TMR and L-TMR silages were well preserved, with low pH and high lactic acid concentrations. The aerobic bacteria and yeast counts in both TMR silages decreased to about 10⁵ cfu/g fresh matter (FM) and below the detection limit, respectively. The lactic acid bacteria count increased to 10⁹ cfu/g FM. The total microbial proteinases activities reached their maximums during the early ensiling stage and then reduced in both TMR silages with fermentation prolonged. Metalloproteinase was the main proteinase when the total proteinases activities reached their maximums, and when ensiling terminated, metallo and serine proteinases played equally important parts in proteolysis in both TMR silages. Strains in the genera Curtobacterium and Paenibacillus were identified as the most dominant proteolytic bacteria in A-TMR and L-TMR, respectively, and both their proteinases were mainly with metalloproteinase characteristics. In the latter ensiling phase, Enterococcus faecium strains became the major sources of proteolytic enzymes in both TMR silages. Their proteinases were mainly of metallo and serine proteinases classes in this experiment. Conclusion: Proteolytic aerobic bacteria were substituted by proteolytic lactic acid bacteria during ensiling, and the microbial serine and metallo proteinases in these strains played leading roles in proteolysis in TMR silages.

• Journal of Korean Academy of Nursing
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• 제17권2호
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• pp.122-136
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• 1987

A group of studies revealed that family members of the seriously ill patient had some needs during the period of patient's hospitalization. Needs of the seriously-ill patient family could be classified into three aspect, i. e. needs on the prognosis of patient, needs on the well-being of family members themselves and needs on hospital environment. Several instrument were developed to measure the needs of the seriously ill patient, but their content tended to overemphasize the aspect of the prognosis of patient. The purpose of this study was to develop a new instrument to measure the needs in the aspect of the seriously ill patient's family themselves in details to increase the cummulative Percentage of the scale. Subjects were 134 family members of the seriously-ill patients, who were bung cared in ICU of seven university hospitals and data were collected from march 16, 1987 to April 11, 1987. The instrument used in this study was made by the author on the basis of results of literature review. Content valitity of the instrument was tested by a professor majoring in nursing and reliability by calculation of Cronbach's α with data of the respondents. Data was analyzed as follows, using SAS, computer system. Factor structures of the seriously ill patients' family needs were elicited by factor analysis. The programme was the Principal Component Factor Analysis Method of factoring employing Varimax Orthogonal Rotation. The influences of the demographic variables on the degree of the seriously-ill patients' family need were analyzed by t-test and P-test. Results were as follows. 1. Needs of the seriously-ill patients' family elicited and their cummulative percentage were: Needs to be supported emotionally, 29.2% Needs to be informed on facilities available, 9.6% Needs to be informed on the patient's prognosis, 7.7%. Needs to be supported spiritually, 5.1%. Needs to be informed on hospital environment, 4.2%. Needs to be helped to spare time, 3.9%. Needs to be informed on their role, 3.5%. Needs to be present near patient, 3.3%. 2. Educational background was found to influence on some factors. College-graduate group had higher Bevel of needs to be . informed on facilities available to be informed on the patient's prognosis, needs to be supported spiritually, needs to be helped to spare time, needs to be informed on their role than high school graduate group. 3. Among the parents, sons and daughters and the relative groups, the parents of the seriously ill patient had highest level of needs to be present near patient. Suggestions for further studies were as follows. 1. As the instruments used in the previous studies had high cummulative percentages in the aspect of the prognosis of patient and that in this study in the aspect of the prognosis of patient and that in this study in the aspect of the seriously ill patient's family themselves, development of a new instrument which combined the items of both of them is needed. 2. A study to clarify the influence of type and number of admission on need to be supported emotionally is needed.

• Korean Journal of Microbiology
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• 제17권4호
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• pp.165-178
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• 1979

Phages of Lactobaciilus casei (PLC) isolated from plant drainage were classified and characterized. The results are as follows : 1. On the basis of host range pattern, phages could be divided into 2 groups (PLC-B and PLC-C). PLC-B group phages could be further divided into 5 sub-groups $(B_1, \;B_2, \;B_3, \;B_4, \;and\;B_5)$. Although PLC-C group phages had the same host range, they could be also divided into 2 sub-groups $(C_1\;and\;C_2)$ by morphlogical type. 2. It was $B_3$ group phages that represented a major proportion (44.4%) of phages tested. However, $B_1$ group phages were shown to have the widest host range. 3. Electron micrographs revealed that the phages fell into three different morphological types. $(B_1, \;B_2, \;and\;B_3)$ group phages hd a hexagonal head (52nm in diameter) and a sheathless noncontractile (245 nm in length). $B_4\;and\;C_2$ group phages had a hexagonal head (56 nm) and a short flexible tail (169nm) having no sheath. $B_5\;and\;C_1$ group phages were shown to have a hexagonal head (81 nm) and a contractile tail (140 nm) having a sheath, a base plate and tail fibers. 4. The inactivation of the phages by antisera indicated that serological relationships correlated completely with morphological types. 5. $B_1, \;C_1\;and\;C_2$ group phages produced a large (1, 2 mm in diameter) plaque with a clear ring. The morphology of plaques of $B_3\;and\;B_5$ group phages was the same as those produced by the above, but the average plaque sizes for $B_3\;and\;B_5$ were 0.8 mm abd 0.5 mm, respectively. $B_2\;and\;B_4$ group phages produced a small (0.5 mm) turbid plaque with an irregular edge. 6. The latent period and the average burst size of $B_1\;and\;B_3$ group phages were 90 min and 100, respectively. These phages reuqired calcium ions for their miltiplication. 7. $B_3$ group phages could not be absrobed to R-variant $KC_1$. 8. The order of resistance of phages to heat was $B_2\;>\;B_1, B_4\;and\;B_5\;>\;B_3\;and\;C_2, \;B_5$ group phages were more stable than $B_3$ in various pH values. $C_2$ group phages were more sensitive to UV irradiation than $B_1\;and\;B_3$ group phages. 9. Strains YIT9018 and IAM 1043 were induced by mitomycin C treatment. Phage particles detected in the lysates had a hexagonal head (38 and 49 nm, respectively), but no tail. Any sensitive indicator strain could not be isolated in spite of repaeated trials.