• Restorative Dentistry and Endodontics
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• 제45권2호
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• pp.19.1-19.8
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• 2020

Objective: This study aimed to evaluate the effect of ultrasonic cleaning of the intracanal post space on the bond strength of fiber posts in oval canals filled with a premixed bioceramic (Bio-C Sealer [BIOC]) root canal sealer. Materials and Methods: Fifty premolars were endodontically prepared and divided into 5 groups (n = 10), based on the type of root canal filling material used and the post space cleaning protocol. A1: gutta-percha + AH Plus (AHP) and post space preparation with ultrasonic cleaning, A2: gutta-percha + BIOC and post space preparation with ultrasonic cleaning, B1: gutta-percha + AHP and post space preparation, B2: gutta-percha + BIOC and post space preparation, C: control group. Fiber posts were cemented with a self-adhesive luting material, and 1 mm thick slices were sectioned from the middle and cervical third to evaluate the remaining filling material microscopically. The samples were subjected to a push-out test to analyze the bond strength of the fiber post, and the results were analyzed with the Shapiro-Wilk, Bonferroni, Kruskal-Wallis, and Mann-Whitney tests (p < 0.05). Failure modes were evaluated using optical microscopy. Results: The results showed that the fiber posts cemented in canals sealed with BIOC had lower bond strength than those sealed with AHP. The ultrasonic cleaning of the post space improved the bond strength of fiber posts in canals sealed with AHP, but not with BIOC. Conclusions: BIOC decreased the bond strength of fiber posts in oval canals, regardless of ultrasonic cleaning.

• The KIPS Transactions:PartC
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• 제15C권2호
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• pp.133-140
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• 2008

In this paper, we propose a high performance elliptic curve cryptographic processor over $GF(2^{163})$. The proposed architecture is based on a modified Lopez-Dahab elliptic curve point multiplication algorithm and uses Gaussian normal basis for $GF(2^{163})$ field arithmetic. To achieve a high throughput rates, we design two new word-level arithmetic units over $GF(2^{163})$ and derive a parallelized elliptic curve point doubling and point addition algorithm with uniform addressing based on the Lopez-Dahab method. We implement our design using Xilinx XC4VLX80 FPGA device which uses 24,263 slices and has a maximum frequency of 143MHz. Our design is roughly 4.8 times faster with 2 times increased hardware complexity compared with the previous hardware implementation proposed by Shu. et. al. Therefore, the proposed elliptic curve cryptographic processor is well suited to elliptic curve cryptosystems requiring high throughput rates such as network processors and web servers.

• The Korean Journal of Pharmacology
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• 제31권2호
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• pp.145-152
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• 1995

The effects and interactions of $4{\beta}-phorbol$ 12,13-dibutyrate(PDB) and polymyxin B(PMB) with adenosine on the electrically-evoked norepinephrine (NE) release were studied in the rat hippocampus. Slices from the rat hippocampus were equilibrated with $^3H-noradrenaline$ and the release of the labelled product, $^3H-NE$, which evoked by electrical stimulation$(3\;Hz,\;2\;ms,\;5\;VCm^{-1},\;rectangular\;pulses)$ was measured. PDB$(0.3{\sim}10\;{\mu}M)$, a selective protein kinase C(PKC) activator, increased the evoked NE release in a dose related fashion while increasing the basal rate of release. And the effects of $1\;{\mu}M$ PDB were significantly inhibited by $0.3\;{\mu}M$ tetrodotoxin(TTX) pretreatment or $Ca^{++}-free$ medium. $PMB(0.03{\sim}1\;mg)$, a specific PKC inhibitor, decreased the NE release in a dose dependent manner while increasing the basal rate of release. Adenosine $(1{\sim}10\;{\mu}M)$ decreased the NE release without changing the basal rate of release, and this effect was significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine$(2\;{\mu}M)$, a selective $A_1-receptor$ antagonist, treatment. Also, adenosine effects were significantly inhibited by PDB-and PMB-pretreatment. These results suggest that the PKC plays a role in the NE release in the rat hippocampus and might be participated in a post-receptor mechanism of the $A_1-adenosine$ receptor.

• The Korean Journal of Physiology and Pharmacology
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• 제15권5호
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• pp.285-289
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• 2011

Shilajit, a medicine herb commonly used in Ayurveda, has been reported to contain at least 85 minerals in ionic form that act on a variety of chemical, biological, and physical stressors. The substantia gelatinosa (SG) neurons of the trigeminal subnucleus caudalis (Vc) are involved in orofacial nociceptive processing. Shilajit has been reported to be an injury and muscular pain reliever but there have been few functional studies of the effect of Shilajit on the SG neurons of the Vc. Therefore, whole cell and gramicidin-perfotrated patch clamp studies were performed to examine the action mechanism of Shilajit on the SG neurons of Vc from mouse brainstem slices. In the whole cell patch clamp mode, Shilajit induced short-lived and repeatable inward currents under the condition of a high chloride pipette solution on all the SG neurons tested. The Shilajit-induced inward currents were concentration dependent and maintained in the presence of tetrodotoxin (TTX), a voltage gated $Na^+$ channel blocker, CNQX, a non-NMDA glutamate receptor antagonist, and AP5, an NMDA receptor antagonist. The Shilajit-induced responses were partially suppressed by picrotoxin, a $GABA_A$ receptor antagonist, and totally blocked in the presence of strychnine, a glycine receptor antagonist, however not affected by mecamylamine hydrochloride (MCH), a nicotinic acetylcholine receptor antagonist. Under the potassium gluconate pipette solution at holding potential 0 mV, Shilajit induced repeatable outward current. These results show that Shilajit has inhibitory effects on the SG neurons of Vc through chloride ion channels by activation of the glycine receptor and $GABA_A$ receptor, indicating that Shilajit contains sedating ingredients for the central nervous system. These results also suggest that Shilajit may be a potential target for modulating orofacial pain processing.

• Journal of The Korean Society of Agricultural Engineers
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• 제55권4호
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• pp.55-63
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• 2013

This study investigates the trends and uncertainty of the impacts of climate change on paddy rice production in the Geumho river basin. The Long Ashton Research Station stochastic Weather Generator (LARS-WG) was used to derive future climate data for the Geumho river basin from 15 General Circulation models (GCMs) for 3 Special Report on Emissions Scenarios (SRES) (A2, A1B and B1) included in the Intergovernmental Panel on Climate Change (IPCC) 4th assessment report. The Food and Agricultural Organization (FAO) AquaCrop, a water-driven crop model, was statistically calibrated for the 1982 to 2010 climate. The index of agreement (IoA), prediction efficiency ($R^2$), percent bias (PBIAS), root mean square error (RMSE) and a visual technique were used to evaluate the adjusted AquaCrop simulated yield values. The adjusted simulated yields showed RMSE, NSE, IoA and PBIAS of 0.40, 0.26, 0.76 and 0.59 respectively. The 5, 9 and 15 year central moving averages showed $R^2$ of 0.78, 0.90 and 0.96 respectively after adjustment. AquaCrop was run for the 2020s (2011-2030), 2050s (2046-2065) and 2090s (2080-2099). Climate change projections for Geumho river basin generally indicate a hotter and wetter future climate with maximum increase in the annual temperature of $4.5^{\circ}C$ in the 2090s A1B, as well as maximum increase in the rainfall of 45 % in the 2090s A2. The means (and ranges) of paddy rice yields are projected to increase by 21 % (17-25 %), 34 % (27-42 %) and 43 % (31-54 %) for the 2020s, 2050s and 2090s, respectively. The A1B shows the largest rice yield uncertainty in all time slices with standard deviation of 0.148, 0.189 and $0.173t{\cdot}ha^{-1}$ for the 2020s, 2050s and 2090s, respectively.

• Journal of The Korean Society of Agricultural Engineers
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• 제60권5호
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• pp.69-80
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• 2018

This study investigated climate change influences over crop water requirement (CWR) and irrigation water requirement (IWR) of the wheat-rice cropping system of Upper Chenab Canal (UCC) command in Punjab Province, Pakistan. PRECIS simulated delta-change climate projections under the A1B scenario were used to project future climate during two-time slices: 2030s (2021-2050) and 2060s (2051-2080) against baseline climatology (1980-2010). CROPWAT model was used to simulate future CWRs and IWRs of the crops. Projections suggested that future climate of the study area would be much hotter than the baseline period with minor rainfall increments. The probable temperature rise increased CWRs and IWRs for both the crops. Wheat CWR was more sensitive to climate-induced temperature variations than rice. However, projected winter/wheat seasonal rainfall increments were satisfactorily higher to compensate for the elevated wheat CWRs; but predicted increments in summer/rice seasonal rainfalls were not enough to complement change rate of the rice CWRs. Thus, predicted wheat IWRs displayed a marginal and rice IWRs displayed a substantial rise. This suggested that future wheat production might withstand the climatic influences by end of the 2030s, but would not sustain the 2060s climatic conditions; whereas, the rice might not be able to bear the future climate-change impacts even by end of the 2030s. In conclusion, the temperature during the winter season and rainfall during the summer season were important climate variables controlling water requirements and crop production in the study area.

• Restorative Dentistry and Endodontics
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• 제41권2호
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• pp.114-120
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• 2016

Objectives: The aim of this study was to compare the push-out bond strength and dentinal tubule penetration of root canal sealers used with coated core materials and conventional gutta-percha. Materials and Methods: A total of 72 single-rooted human mandibular incisors were instrumented with NiTi rotary files with irrigation of 2.5% NaOCl. The smear layer was removed with 17% ethylenediaminetetraacetic acid (EDTA). Specimens were assigned into four groups according to the obturation system: Group 1, EndoRez (Ultradent Product Inc.); Group 2, Activ GP (Brasseler); Group 3, SmartSeal (DFRP Ltd. Villa Farm); Group 4, AH 26 (Dentsply de Trey)/gutta-percha (GP). For push-out bond strength measurement, two horizontal slices were obtained from each specimen (n = 20). To compare dentinal tubule penetration, remaining 32 roots assigned to 4 groups as above were obturated with 0.1% Rhodamine B labeled sealers. One horizontal slice was obtained from the middle third of each specimen (n = 8) and scanned under confocal laser scanning electron microscope. Tubule penetration area, depth, and percentage were measured. Kruskall-Wallis test was used for statistical analysis. Results: EndoRez showed significantly lower push-out bond strength than the others (p < 0.05). No significant difference was found amongst the groups in terms of percentage of sealer penetration. SmartSeal showed the least penetration than the others (p < 0.05). Conclusions: The bond strength and sealer penetration of resin-and glass ionomer-based sealers used with coated core was not superior to resin-based sealer used with conventional GP. Dentinal tubule penetration has limited effect on bond strength. The use of conventional GP with sealer seems to be sufficient in terms of push-out bond strength.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• 제17권2호
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• pp.39-42
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• 2011

The aim of this study was to develop the appropriate packaging method for minimally processed sliced onions. The films of different gas permeabilities (LDPE $30{\mu}m$, PD900 and PD941) were used for packaging 1300g of onion slices cut into octuplicate pieces. Perforated LDPE package was prepared as control for comparison. The package atmosphere and onion quality were measured through storage at $1^{\circ}C$ for 38 days. PD900 package of the lowest gas permeability was the best in keeping the fresh-cut onions by maintaining MA conditions of 1-3% $O_2$ and 4-11% $CO_2$ concentrations. The benefits were reduced discoloration, decay and soakness.

• Tunnel and Underground Space
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• 제20권5호
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• pp.360-368
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• 2010

The paper presents a case study from a surface mine where the controlled augmentation of throw and drop of the blasted muck piles was warranted to spread the muck piles on the lower berm of the bench. While the augmentation of throw increased the lateral spread and the looseness of the broken muck, the augmentation of drop significantly lowered the muck pile height for easy excavation by the excavators. In this light, the present paper highlights and discusses some pertinent changes in the blast design parameters for such specialized application of cast blasting in a surface mine, where a sandstone bench, with average height of 22-24 m was to be made amenable for excavation by 10 m3 rope shovels, which possessed maximum digging capability of up to 14 m. The results of tailoring the blast design parameters for augmentation of throw and drop are compared with the baseline blasts which were earlier practiced on the same bench by dividing the full height of the bench in 2-slices; upper slice (10-14 m high) and lower slice (12-15 m high). Results of fragment size, its distribution and total cycle time of excavator (shovel) are presented, and discussed.

• Biomolecules & Therapeutics
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• 제28권1호
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• pp.74-82
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• 2020

Alzheimer's disease (AD) is a progressive and most frequently diagnosed neurodegenerative disorder. However, there is still no drug preventing the progress of this disorder. β-Amyrin, an ingredient of the surface wax of tomato fruit and dandelion coffee, is previously reported to ameliorate memory impairment induced by cholinergic dysfunction. Therefore, we tested whether β-amyrin can prevent AD-like pathology. β-Amyrin blocked amyloid β (Aβ)-induced long-term potentiation (LTP) impairment in the hippocampal slices. Moreover, β-amyrin improved Aβ-induced suppression of phosphatidylinositol-3-kinase (PI3K)/Akt signaling. LY294002, a PI3K inhibitor, blocked the effect of β-amyrin on Aβ-induced LTP impairment. In in vivo experiments, we observed that β-amyrin ameliorated object recognition memory deficit in Aβ-injected AD mice model. Moreover, neurogenesis impairments induced by Aβ was improved by β-amyrin treatment. Taken together, β-amyrin might be a good candidate of treatment or supplement for AD patients.