• Restorative Dentistry and Endodontics
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• 제8권1호
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• pp.61-68
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• 1982

This study was undertaken to compare the histopathological effects of the fractionated doses of 2,400, 4,800 and 7,200 rads of Cobalt-60 irradiation on the teeth of the sixty eight rats (Wester strain), weighing approximately 130gm. They were devided into four groups; no irradiation as a control (Group I) and others (Group II, III, and IV) which received different doses of radiation using 1.25 Mev RAC-120 Cobalt-60 Teletherapy Unit with exposure dose rate 69 rads/min, TSD 80cm. Experimental animals received 600 rads every three days until the total dosage of their groups were reached. Experimental animals were sacrified at the 1st day, 1st, 2nd, 3rd, 4th, 5th and 6th week irradiation. The following histopathologic findings were obtained: 1. The Group II, received 2,400 rads, showed no histopamologic changes essentially same as those of the control Group. 2. In the Groups III and IV, received 4,800 rads and 7,200 rads, disarray of the normal palasading arrangement of the odontoblastic cells, vacuolar degeneration in the odontoblastic layer, osteodentin and dentinal niches in the anterior teeth were observed. 3. There were no distinct changes in the posterior teeth in the Groups III and IV. 4. The ameloblast cells seemed to be less sensitive to radiation damage than the odontoblast cells.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.761-766
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• 2008

Photoresponsive arylether dendrimers Bis-azo-Gn(3,5) 1a-1c and Bis-azo-Gn(3,4,5) 2a-2c (n = 1-3) with an azobenzene unit at the core and several vinyl groups (3,5-bis(but-3-enyloxy)phenyl groups or 3,4,5-tris(but-3- enyloxy)phenyl groups) at the periphery have been prepared. Their structures and reversible trans-cis isomerization behaviors have been investigated by $^1H$-NMR, $^{13}C$-NMR, MALDI-TOF-Mass, and UV-vis spectra. All six azobenzene-cored dendrimers carried out very fast trans $\rightarrow$ cis photoisomerization on irradiation of 350 nm light and reached to the photostationary state within 180 s. During the dark incubation, slow thermal back reversion from cis to trans form is observed for all six dendrimers and is completed within 3 days for 1a-1c and 1 day for 2a-2c. Isomerization efficiency decreases with increasing generation. However, the initial reaction rates of both trans $\rightarrow$ cis photochemical isomerization and cis $\rightarrow$ trans thermal isomerization increases significantly with increasing generation for dendrimers for 1a-1c but only slightly for 2a-2c.

• Journal of Korean Biological Nursing Science
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• 제7권2호
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• pp.5-15
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• 2005

The purpose of this study was to compare the sleep and fatigue between groups with two shift and three shift nurses. A total of 14 nurses working in Neonatal Intensive Care Unit(NIC) were included with the seven for two shifts and the other seven for three shifts. Data were collected by Korean version of sleep tool(Oh et al., 1998) and fatigue symptom tool(Kim et al., 2001) and analyzed using SPSS PC 12.0. The results of the study were as follows: 1) There was statistically a significant difference in the number of total sleep hour and no difference in fatigue between groups. 2) There were no significant differences found in both sleep and fatigue by demographic characteristics between groups. 3) There were no correlations between sleep and fatigue in both groups. Through the further future studies, the findings of this study were expected to provide an opportunities for exploring the information on 2-shift nurses as well as 3-shift nurses and to offer the fundamental data on an arrangement of work force according to the types of shift work.

• 임상간호연구
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• 제27권1호
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• pp.77-84
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• 2021

Purpose: Malnutrition affects all age groups, but older adults are particularly more vulnerable to nutritional deficiencies. This study evaluated the age-specific factors affecting malnutrition in hospitalized older adults. Methods: A retrospective study was conducted on inpatient elderly people who received artificial nutrition from 2010 to 2017. Data of demographics, diagnosis, type of nutrition therapy, number of comorbidity, fall risk assessment, Acute Physiologic Assessment and Chronic Health Evaluation (APACHE) score, and intensive care unit admission were collected. Malnutrition was defined as a body mass index (BMI) of less than 18.5 kg/m². Patients were classified as the young-old (65~74 years old), the old-old (75~84 years old), or the oldest-old (85 years old or older). Results: A total of 7,130 older adults were included, and 4,028 patients were classified as the young-old, 2,506 into the old-old, and 596 into the oldest-old. Proportion of malnutrition was higher in the oldest-old compared to the other groups. In multivariate analysis, parenteral nutrition, alcohol, and high risk of falls were factors affecting malnutrition in all groups. Parenteral nutrition and alcohol in the young-old, high risk of falls in the old-old, and male sex in the oldest-old were the factors affecting malnutrition by the age group. Conclusion: Older age was the most significant factor affecting malnutrition. Specific strategies by age are needed to improve nutritional status in hospitalized older adults as influencing factors for malnutrition vary among different age groups.

• International Journal of Fluid Machinery and Systems
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• 제9권2호
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• pp.129-136
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• 2016

An experimental investigation was carried out to improve the performance of a counter-rotating type horizontal-axis tidal stream power unit. Front and rear blades were designed separately based on modified blade element momentum (BEM) theory, and their performances at different conditions of blade tip speed ratio were measured in a wind tunnel. Three different groups of blades were designed successively, and the results showed that Group3 possessed the highest power coefficient of 0.44 and was the most satisfactory model. This experiment shows that properly increasing diameter and reducing chord length will benefit the performance of the blade.

• 한국환경교육학회지:환경교육
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• 제21권4호
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• pp.111-122
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• 2008

This study is to evaluate the effect of roleplaying-centered STS program on the science-related attitude, the academic achievement, and the problem solving ability in "Environment" unit of high school Science. 90 students in grade 10 were divided into two groups, the experimental group applied the roleplaying-centered STS program and the control group applied the traditional lecture-centered class. The pretest was implemented to measure the science-related attitude, and the posttest was implemented to measure the science-related attitude, the academic achievement, and problem solving ability. The collected data were analyzed by ANCOVA and Correlation Analysis with SPSS program. The results are as follows: First, the experimental group was not significantly different from the control group in the science-related attitude and in the academic achievement(p>.05). Second, the experimental group significantly showed much better problem solving ability than the control group(p<.05). Third, a significant correlation was recognized between the academic achievement and the problem solving ability(p<.01).

• Parasites, Hosts and Diseases
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• 제51권6호
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• pp.759-761
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• 2013

Lymphatic filariasis is a common parasitic disease of cats in tropical regions including Thailand. The objective of this study was to determine the efficacy of ivermectin against microfilariae of Brugia pahangi in naturally infected cats. Eight cats naturally infected with B. pahangi were divided into control (untreated) and treated groups. Cats in the latter group were given ivermectin injection at 400 ${\mu}g/kg$ weekly for 2 months. Microfilariae were counted every week until 48 weeks. Microfilaremia was significantly decreased in the treated group 4 weeks after starting the treatment and become zero at week 9 and afterwards. On the other hand, cats in the control group had high microfilaremia throughout the study. It was successful to treat and control B. pahangi infection in naturally infected cats using ivermectin.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1052-1052
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• 2001

Hear infrared (NIR) spectra were measured, at five temperatures, for forty-eight samples of honey, from a variety of geographical and botanical sources, and the data has been used to explore the possibility of using NIR spectroscopy for testing label claims concerning the geographical and botanical source of honey being offered for sale to the public. These results demonstrate that the successful characterization of the botanical source of a honey may be obtained by NIR spectroscopy. Further work with large numbers of samples and groups will be required to realized this potential. Additional analysis of these data suggest that research into new ways of obtaining information on the change of absorption with temperature might be beneficial for a range of technologies.

• 대한산업공학회지
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• 제17권1호
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• pp.75-82
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• 1991

This research is concerned with Machine-Part Group Formation(MPGF) methodology for Flexible Manufacturing Systems(FMS). The purpose of the research is to develop a new heuristic algorithm for effectively solving MPGF problem. The new algorithm is proposed and evaluated by 100 machine-part incidence matrices generated. The performance measures are (1) grouping ability of mutually exclusive block-diagonal form. (2) number of unit group and exceptional elements, and (3) grouping time. The new heuristic algorithm has the following characteristics to effectively conduct MPGF : (a) The mathematical model is presented for rapid forming the proper number of unit groups and grouping mutually exclusive block-diagonal form, (b) The simple and effective mathematical analysis method of Rank Order Clustering(ROC) algorithm is applied to minimize intra-group journeys in each group and exceptional elements in the whole group. The results are compared with those from Expert System(ES) algorithm and ROC algorithm. The results show that the new algorithm always gives the group of mutually exclusive block-diagonal form and better results(85%) than ES algorithm and ROC algorithm.

• 대한수학회보
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• 제53권4호
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• pp.1105-1112
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• 2016

Describing the group of units $U({\mathbb{Z}}G)$ of the integral group ring ${\mathbb{Z}}G$, for a finite group G, is a classical and open problem. In this note, we show that $$U_1({\mathbb{Z}}[T{\times}C_2]){\sim_=}[F_{97}{\rtimes}F_5]{\rtimes}[T{\times}C_2]$$, where $T={\langle}a,b:a^6=1,a^3=b^2,ba=a^5b{\rangle}$ and $F_{97}$, $F_5$ are free groups of ranks 97 and 5, respectively.