• The Journal of Advanced Prosthodontics
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• v.5 no.3
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• pp.333-340
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• 2013

PURPOSE. This study was accomplished to assess the biomechanical state of different retaining methods of bar implant-overdenture. MATERIALS AND METHODS. Two 3D finite element models were designed. The first model included implant overdenture retained by Hader-clip attachment, while the second model included two extracoronal resilient attachment (ERA) studs added distally to Hader splint bar. A non-linear frictional contact type was assumed between overdentures and mucosa to represent sliding and rotational movements among different attachment components. A 200 N was applied at the molar region unilaterally and perpendicular to the occlusal plane. Additionally, the mandible was restrained at their ramus ends. The maximum equivalent stress and strain (von Mises) were recorded and analyzed at the bone-implant interface level. RESULTS. The values of von Mises stress and strain of the first model at bone-implant interface were higher than their counterparts of the second model. Stress concentration and high value of strain were recognized surrounding implant of the unloaded side in both models. CONCLUSION. There were different patterns of stress-strain distribution at bone-implant interface between the studied attachment designs. Hader bar-clip attachment showed better biomechanical behavior than adding ERA studs distal to hader bar.

• Journal of Environmental Science International
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• v.14 no.5
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• pp.513-520
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• 2005

For the destruction of toxic chlorinated organic compounds, this study proposes improved supercritical water oxidation method (multistep oxidation) using sodium nitrate as an oxidizer. This method solves the problems involved in the existing supercritical water oxidation method. Multistep oxidation means that $NaNO_3$ is oxidized to $N_2\;via\;NaNO_2$ and NO. Toxic and hard to destroy organic substances like para-dichlorobenzen(4-DCBz), polychlorinate biphenyl(PCB) ware oxidized to non toxic substances in a condition, in which rapid pressure and temperature rise is restrained as much as possible. 4-dichlorobenzene(4-DCBz) and Polychlorinate biphenyl(PCB) in condition$(450^{\circ}C,\;p_w=0.25g/cm^3,\;30min)$ Was discomposed perfectly.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.11
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• pp.1873-1880
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• 2001

The effects of restraint of pressure induced bending(PIB) on crack opening for circumferential through-wall crack in a pipe were investigated. In this study, the elastic and elastic-plastic finite element analyses were performed to evaluate crack opening displacement(COD) for various restraint conditions and crack size. The results showed the restraint of PIB decreased crack opening for a given crack size and tensile stress, and the decrease in crack opening was considerable for large crack and short restraint length. A1so, the effect was more significant in tole results of elastic-plastic analysis compared with in the elastic analysis results. In the elastic-plastic analysis results, tole restraint effect was increased with increasing applied tensile stress corresponding to internal pressure. Additionally, the restraint effect on COD was independent on the variation in pipe diameter and decreased with increasing pipe thickness, and It depended on not total restraint length but shorter restraint length for non-symmetrically restrained.

• Steel and Composite Structures
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• v.22 no.5
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• pp.1115-1140
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• 2016

This paper proposes an extension of the Improved Forced Based Design procedure to 3D steel structures. The Improved Forced Based Design (IFBD) procedure consists of a more rational sequence of the design checks proposed in Eurocode 8 and involves a more realistic selection of the behaviour factor instead of selecting an empirical value based on the ductility class and lateral resisting system adopted. The design procedure was tested on a group of four 3D steel structures, composed by moment-resisting frames with three storeys height and the same plan configuration in all storeys. The plan configuration was defined in order to target lateral restrained or unrestrained systems as well as plan regular or irregular structures. The same group of structures was also designed according to the force-based process prescribed in Eurocode 8. The member sizes obtained through the two approaches were compared and the seismic performance was assessed through nonlinear static and time-history analyses. The limit states referred to structural and non-structural damage, considering the two levels design approach, which are the serviceability and the ultimate limit states, were examined. The results obtained reveal that the IFBD leads to more economical structures that still comply with the performance requirements prescribed in Eurocode 8.

• Journal of Pharmacopuncture
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• v.23 no.1
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• pp.1-7
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• 2020

Nicotine, primary component of tobaco produces craving and withdrawal effect both in humans and animals. Nicotine shows a close resemblance to other addictive drugs in molecular, neuroanatomical and pharmacological, particularly the drugs which enhances the cognitive functions. Nicotine mainly shows its action through specific nicotinic acetylcholine receptors located in brain. It stimulates presynaptic acetylcholine receptors thereby enhancing Ach release and metabolism. Dopaminergic system is also stimulated by it, thus increasing the concentration of dopamine in nuclear accumbens. This property of nicotine according to various researchers is responsible for reinforcing behavioral change and dependence of nicotine. Various researchers have also depicted that some non dopaminergic systems are also involved for rewarding effect of nicotinic withdrawal. Neurological systems such as GABAergic, serotonergic, noradrenergic, and brain stem cholinergic may also be involved to mediate the actions of nicotine. Further, the neurobiological pathway to nicotine dependence might perhaps be appropriate to the attachment of nicotine to nicotinic acetylcholine receptors, peruse by stimulation of dopaminergic system and activation of general pharmacological changes that might be responsible for nicotine addiction. It is also suggested that MAO A and B both are restrained by nicotine. This enzyme helps in degradation dopamine, which is mainly responsible for nicotinic actions and dependence. Various questions remain uninsurable to nicotine mechanism and require more research. Also, various genetic methods united with modern instrumental analysis might result for more authentic information for nicotine addiction.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.4 no.1
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• pp.23-48
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• 1980

Libraries are social apparatuses made by social needs and functions, each class of services and technology in them were changed and developed variously adapting to chronological conditions. There is reaching the interest about development in the information system to deal with it's all materials effectively, but most of libraries are interfacing from the limit of materials and manpower. Some obstacle factors restrained in the attainment of purposes and is made Sufficiently services by librarians through the information networks for libraries, they devise the utilization of materials widely in libraries and information centers. As the pre-condition of library networks, the mathematical model of organization and it's formular, 29 universities and 7 public libraries in seoul are to make the non-directed and the directed networks, and then the former has 5 groups, the latter has 1 group by the switching center. I studied for the switching centers from 6 groups experimentally. Organization, finances, cataloging and Situation that are some obstacle factors of the information networks for libraries were studied the alternatives of them. When we can have supports of the nation actively for the making networks in geographical and various libraries and get grants of it, many agencies and industries, we can achieve the purpose by social apparatuses in the information society.

• Steel and Composite Structures
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• v.33 no.4
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• pp.525-535
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• 2019

The seismic performance of steel frames equipped with a particular type of bending dissipative braces (BDBs) having U elements, which has recently been introduced and tested by the authors, is investigated. For this purpose, two structural systems, i.e., simple and dual steel building frames, both with diagonal BDBs and different number of stories, are considered. After providing a design method of this new BDB, the detailed structural models are developed in the OpenSees platform to perform nonlinear dynamic analyses. Seismic performance factors like ductility, overstrength, response modification and deflection amplification factors are calculated using incremental dynamic analysis (IDA). In addition, to assess the damage probability of the structural models, their seismic fragilities are developed. The results show high energy dissipation capacity of both structural systems while the number of U elements needed for the bracing system of each story in the moment frames are less than those in the corresponding non-moment (simple) frames. The average response modification and deflection amplification factors for both structural schemes are obtained about 8.6 and 5.4, respectively, which are slightly larger than the corresponding recommended values of ASCE for the typical buckling-restrained braces (BRBs).

• Journal of Veterinary Clinics
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• v.38 no.5
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• pp.244-248
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• 2021

A 10-year-old Thoroughbred mare was referred to the Jeju National University Equine Hospital with roaring, dyspnea, and weight loss. On endoscopic examination, the horse was diagnosed with right arytenoid chondritis. Surgical treatment was selected due to the failure of a previous medical treatment. Permanent tracheostomy was performed in a standing position. The horse was restrained and tied in a proper position in the stock. The cranial parts of the 2nd to 5th tracheal cartilages were resected, as were the associated skin, mucosa, muscle, and cartilages. After the stoma was formed, external mucosa and skin were sutured using a simple interrupted method. The horse was hospitalized for 22 days receiving postoperative care including antibiotics, non-steroidal anti-inflammatory drugs, dressing as required, and was pregnant six months after the surgery. A permanent tracheostomy is thought to be effective in horses with diseases causing upper respiratory tract obstruction.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6893-6898
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• 2014

Curcumin and its analogues have been reported to exert anti-cancer activity against a variety of tumors. Here, we reported A501, a new curcumin analogue. The effect of A501 on cell viability was detected by MTT assay, the result showed that A501 had a better inhibiting effect on the four non-small cell lung cancer (NSCLC) cells than that of curcumin. Moreover, Colony forming experiment showed A501 significant restrained cell proliferation. Flow cytometry displayed A501 can cause G2/M arrest and induce apoptosis. Western blotting showed that A501 decreased the expression of cyclinB1, cdc-2, bcl-2, while increased the expression of p53, cleaved caspase-3 and bax. In conclusion, curcumin analogues A501 played antitumor activity by inhibiting cell proliferation and inducing apoptosis of NSCLC cells. And it was likely to be a promising starting point for the development of curcumin-based anticancer drugs.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.1
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• pp.41-54
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• 1999

For free vibration of non-symmetric thin-walled circular arches including restrained warping effect, the elastic strain and kinetic energy is derived by introducing displacement fields of circular arches in which all displacement parameters are defined at the centroid axis. The cubic Hermitian polynomials are utilized as shape functions for development of the curved thin-walled beam element having eight degrees of freedom. Analytical solution for in-plane free vibration behaviors of simply supported thin-walled curved beams with monosymmetric cross-sections is newly derived. Also, a finite element formulation using two noded curved beams element is presented by evaluating elastic stiffness and mass matrices. In order to illustrate the accuracy and practical usefulness of this study, analytical and numerical solutions for free vibration of circular arches are presented and compared with solutions analyzed by the straight beam element and the ABAQUS's shell element.