• The Journal of Korean Academy of Prosthodontics
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• v.46 no.4
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• pp.396-408
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• 2008

Statement of problem: Within the elastic limit of the screw, the greater the preload, the tighter and more secure the screw joint. However, additional tensile forces can incur plastic deformation of the abutment screw when functional loads are superimposed on preload stresses, and they can elicit the loosening or fracture of the abutment screw. Therefore, it is necessary to find the optimum preload that will maximize fatigue life and simultaneously offer a reasonable degree of protection against loosening. Another critical factor in addition to the applied torque which can affect the amount of preload is the joint connection type between implant and abutment. Purpose: The purpose of this study was to evaluate the influence of tightening torque on the implant-abutment screw joint stability. Material and methods: Respectively, three different amount of tightening torque (20, 30, and 40 Ncm) were applied to implant systems with three different joint connections, one external butt joint and two internal cones. The initial removal torque value and the postload (cyclic loading up to 100,000 cycles) removal torque value of the abutment screw were measured with digital torque gauge. Then rate of the initial and the postload removal torque loss were calculated for the comparison of the effect of tightening torques and joint connection types between implant and abutment on the joint stability. Results and conclusion: 1. Increase in tightening torque value resulted in significant increase in initial and postload removal torque value in all implant systems (P < .05). 2. Initial removal torque loss rates in SS II system were not significantly different when three different tightening torque values were applied (P > .05), however GS II and US II systems exhibited significantly lower loss rates with 40 Ncm torque value than with 20 Ncm (P < .05). 3. In all implant systems, postload removal torque loss rates were lowest when the torque value of 30 Ncm was applied (P < .05). 4. Postload removal torque loss rates tended to increase in order of SS II, GS II and US II system. 5. There was no correlation between initial removal torque value and postload removal torque loss rate (P > .05).

• Journal of Ginseng Research
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• v.43 no.1
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• pp.58-67
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• 2019

Background: Diabetic neuropathy is one of the most devastating ailments of the peripheral nervous system. Neuropathic pain develops in ~30% of diabetics. Here, we examined the suppressive effect of GS-KG9 on neuropathic pain induced by streptozotocin (STZ). Methods: Hyperglycemia was induced by intraperitoneal injection of STZ. Rats showing blood glucose level > 250 mg/dL were divided into five groups, and treatment groups received oral saline containing GS-KG9 (50 mg/kg, 150 mg/kg, or 300 mg/kg) twice daily for 4 wk. The effects of GS-KG9 on pain behavior, microglia activation in the lumbar spinal cord and ventral posterolateral (VPL) nucleus of the thalamus, and c-Fos expression in the dorsal horn of the lumbar spinal cord were examined. Results: The development of neuropathic pain began at Day 5 and peaked at Week 4 after STZ injection. Mechanical and thermal pains were both significantly attenuated in GS-KG9-treated groups from 10 d after STZ injection as compared to those in the STZ control. GS-KG9 also repressed microglia activation in L4 dorsal horn and VPL region of the thalamus. In addition, increase in c-Fos-positive cells within L4 dorsal horn lamina I and II of the STZ control group was markedly alleviated by GS-KG9. Conclusion: These results suggest that GS-KG9 effectively relieves STZ-induced neuropathic pain by inhibiting microglial activation in the spinal cord dorsal horn and VPL region of the thalamus.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.89-98
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• 2009

Objectives : The purpose of this study was to evaluate effects of processed sulfur with red ginseng on streptozotocin(STZ) induced diabetic rats for expansion of processed sulfur internal application. Methods : We prepared red ginseng with non processed sulfur extracts(GS), red ginseng with processed sulfur I extracts(GPS I) and red ginseng with processed sulfur II extracts(GPS II). In the present study, we examined about contents of crdue saponin, antioxidant activity, $\alpha$-glucosidase inhibitory activity, and effects of STZ induced diabetic rats. Results : Contents of crude saponin increased by processed sulfur, and GPS II was shown highest contents in crude saponin and sulfur compared with another groups. Electron donating ability of GPS II was shown highest activity compared with GS and GPS I, SOD-like activity showed same tendency as electron donating ability at 1 $mg/m\ell$ concentration. Inhibitory activity of $\alpha$-glucosidase was approximately same level in acarbose and GPS II. Blood glucose level of GPS II group was decreased 18.34% compared with DC(diabetes control) group and maintained stability range in glucose level. but GS and GPS I showed high level compared to GPS II. Serum triglycerides concentration also showed lowest level in GPS II. The activity of ALT, AST and ALP was shown high level in diabetic induced groups, and lowest level in GPS II. Creatinine was shown non-significantly difference in each groups and GPS II was shown lowest level in BUN. Conclusions : These results suggested that processed sulfur with red ginseng have improvement effects on diabetes and internal application of processed sulfur with red ginseng have no specific toxicity in liver and kidney.

• The Journal of Korea CHUNA Manual Medicine
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• v.3 no.1
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• pp.15-29
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• 2002

Objectives : This experimental study was designed to investigate the effects of Galgunseunggi-tang on the weight of obese rats Induced by high fat diet. Methods : A series of have been conducted in order to measure the effects of the above materials weight. serum and fat cells. The have been performed on; (1) the Increasing amount of body weight; (2) the quantity of total cholesterol, tryglyceride, total lipid, free fatty acid, phospholipid, HDL -cholesterol and LDL -cholesterol in serum; (3) the average size of epididymal fat cells and the area rate of fat drops in hepatic lobule. Results : The results were summarized as follows: 1. It was proved that Galgunseunggi-tang suppressed the increasing amount of body weight. GS II group (supplied 60mg per 100g) showed a significant value. 2. It was proved that Galgunseunggi-tang improved the total cholesterol, HDL -cholesterol In serum. but did not show a significance. 3. It was proved that Galgunseunggi-tang decreased the quantify of free fatty acid, phospholipid, LDL -cholesterol in serum. GS I group (supplied 30mg per 100g) showed a significant value. 4. It was proved that Galgunseunggi-tang decreased the quantity of triglyceride, total lipid in serum, and GS II group showed a significant value. 5. Galgunseunggi-tang decreased the average size of epididymal fat cells and the area rate of fat drops In hepatic lobule, and GS I group showed a significant value. Conclusions : Based on the above result, it is assumed that the clinical application of Galgunseunggi-tang can help the treatment of obesity.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.73-82
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• 2008

Dental caries is an infectious disease caused by mutans streptococci, and is a primary etiologic agent of dental caries in humans. The molecular pathogenesis of mutans streptococcal-associated dental caries occurs in three phases. Firstly, S. mutans attaches to tooth surface via a cell surface adhesion termed antigen I/II. In the second phase, the glucosyltransferase(GTFs) synthesize polymers like glucans in the presence of sucrose. In the third phase, the multivalent glucans interacts with glucan binding proteins (GBPs) and they make dental plaque and accumulation of microorganisms. Many studies and clinical trials have indicated that a mucosal immune response to these antigens(Ag I/II, GTFs, GBPs) of S. mutans can influence the pathogenesis of dental caries. So these antigens can be important vaccine candidates for immunologic intervention against dental caries. In this study, we cloned the genes for GTFb, GTFc, GTFd from S. mutans GS-5 and did the nucleotide sequence analysis. And the recombinant proteins of GTFd and N-terminus of GTFd were expressed. Intact GTF which we get from this experiment can be used for antibody production specific for any GTF activity domain through animal experiment.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.12
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• pp.1678-1683
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• 2014

This study considers a problem of genomic selection (GS) for adjacent genetic markers of Yorkshire pigs which are typically correlated. The GS has been widely used to efficiently estimate target variables such as molecular breeding values using markers across the entire genome. Recently, GS has been applied to animals as well as plants, especially to pigs. For efficient selection of variables with specific traits in pig breeding, it is required that any such variable selection retains some properties: i) it produces a simple model by identifying insignificant variables; ii) it improves the accuracy of the prediction of future data; and iii) it is feasible to handle high-dimensional data in which the number of variables is larger than the number of observations. In this paper, we applied several variable selection methods including least absolute shrinkage and selection operator (LASSO), fused LASSO and elastic net to data with 47K single nucleotide polymorphisms and litter size for 519 observed sows. Based on experiments, we observed that the fused LASSO outperforms other approaches.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.164-173
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• 2009

Purpose: The purpose of this study was to evaluate the effect of abutment material on screw-loosening before and after cyclic loading. Among the different materials of abutments, zirconia and metal abutment were used. Material and methods: Two types of implant systems: external butt joint(US II, Osstem Implant, Korea) and internal conical joint(GS II, Osstem Implant, Korea) were used. In each type, specimens were divided into two different kinds of abutments: zirconia and metal(n=5). The implant was rigidly held in a special holding to device ensure fixation. Abutment was connected to 30 Ncm with digital torque gauge, and was retightened in 30 Ncm after 10 minutes. The initial removal torque values were measured. The same specimens were tightened in 30 Ncm again and held in the cycling loading simulator(Instron, USA) according to ISO/FPIS 1480. Cycling loading tests were performed at loads 10 to 250 N, for 1 million cycles, at 14 Hz,(by subjecting sinusoidal wave from 10 to 250 N at a frequency of 14 Hz for 1 million cycles,) and then postload removal torque values were evaluated. Results: 1. In all samples, the removal values of abutment screw were lower than tightening torque values(30 Ncm), but the phenomenon of the screw loosening was not observed. 2. In both of the implant systems, initial and postload removal torque of zirconia abutment were significantly higher than those of metal abutment(P<.05). 3. In both of the implant systems, the difference in removal torque ratio between zirconia abutment and metal abutment was not significant(P>.05). 4. In metal abutments, the removal torque ratio of GS II system(internal conical joint system) was lower than that of US II system(external butt joint system)(P<.05). 5. In zirconia abutments, the difference in removal torque ratio between the two implant systems was not significant(P>.05). Conclusion: Zirconia abutment had a good screw joint stability in the condition of one million cycling loading.

• Journal of Korean Society on Water Environment
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• v.27 no.2
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• pp.218-227
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• 2011

The objective approach for assessment of stream naturalness is an essential part of the stream restoration project. This study proposes the methodology for the assessment of stream naturalness considering physical, biological and chemical factors. Physical factors consists of riffle and pool, river bed material, bank protection, floodplain vegetation and levee materials; biological factors are benthic macroinvertebrate, KSI (Korean Saprobic Index), and IBI (Index of Biological Integrity) and chemical factors are pH, DO (dissolved oxygen), and TP (total phosphorus). This procedure is applied to the Mokgamcheon. As a result, the downstream of Mokgamcheon (zone I) needs the prompt improvement of stream naturalness, compared to the others (zone II and III). This evaluation technique will be an effective tool to quantify the stream naturalness and can be used to set the target of stream restoration project.

• The Plant Pathology Journal
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• v.29 no.4
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• pp.397-409
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• 2013

The full-genome sequences of fourteen isolates of Broad bean wilt virus 2 (BBWV2), collected from broad bean, pea, spinach, bell pepper and paprika plants in Korea during the years 2006-2012, were determined and analyzed comparatively along with fifteen previously reported BBWV2 genome sequences. Sequence analyses showed that RNA-1 and RNA-2 sequences of BBWV2 Korean isolates consisted of 5950-5956 and 3568-3604 nucleotides, respectively. Full-length genome sequence-based phylogenetic analyses revealed that the BBWV2 Korean isolates could be divided into three major groups comprising GS-I (isolates BB2 and RP7) along with isolate IP, GS-II (isolates BB5, P2, P3 and RP3) along with isolate B935, and GS-III including 16 BBWV2 Korean isolates. Interestingly, GS-III appears to be newly emerged and predominant in Korea. Recombination analyses identified two recombination events in the analyzed BBWV2 population: one in the RNA-1 of isolate K and another one in the RNA-2 of isolate XJ14-3. However, no recombination events were detected in the other 21 Korean isolates. On the other hand, out of 29 BBWV2 isolates, 16 isolates were found to be re-assortants, of which each RNA segment (i.e. RNA1 and RNA2) was originated from different parental isolates. Our findings suggested that reassortment rather than recombination is a major evolutionary force in the genetic diversification of BBWV population in Korea.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.4
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• pp.378-385
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• 2014

In this research, we investigate electrical performance and electrochemical properties of graphene supported Pt (Pt/G) and PtM (M = Ni and Y) alloy catalysts (PtM/Gs) that are synthesized by modified polyol method. With the PtM/Gs that are adopted for oxygen reduction reaction (ORR) as cathode of proton exchange membrane fuel cells (PEMFCs), their catalytic activity and ORR performance and electrical performance are estimated and compared with one another. Their particle size, particle distribution and electrochemically active surface (EAS) area are measured by TEM and cyclic voltammetry (CV), respectively. On the other hand, regarding ORR activity and electrical performance of the catalysts, (i) linear sweeping voltammetry by rotating disk electrode and rotating ring-disk electrode and (ii) PEMFC single cell tests are used. The TEM and CV measurements demonstrate particle size and EAS of PtM/Gs are compatible with those of Pt/G. In case of PtNi/G, its half-wave potential, kinetic current density, transferred electron number per oxygen molecule and $H_2O_2$ production % are excellent. Based on data obtained by half-cell test, when PEMFC singlecell tests are carried out, current density measured at 0.6V and maximum power density of the PEMFC single cell employing PtNi/G are better than those employing Pt/G. Conclusively, PtNi/Gs synthesized by modified polyol shows better ORR catalytic activity and PEMFC performance than other catalysts.