• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.324-331
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• 2015

Thyroid hormones are essential for cellular energy homeostasis and regulation by interacting with the sympathetic nervous system. This study was conducted to investigate the relationship between thyroid hormone and risk factors of metabolic syndrome for medical checkups of male patients. The study subjects were 12,250 males between 20~80 years old who visited the hospital for a health check-up at one General Hospital in Gyeonggi-do during the period of January 2011 to December 2013. According to the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI), the metabolic syndrome criteria is defined as the presence of 3 or more risk factors. FT4 was lower in the metabolic syndrome group than in the normal group (p<0.001). The level of FT4 decreased as the levels of abdominal obesity (p=0.001), hypertriglyceridemia (p<0.001), blood pressure (p=0.005) and blood glucose (p=0.005) increased. The TSH level increased hypertriglyceridemia (p=0.047). FT4 had an influence on the waist circumference and triglyceride (p<0.001). HbA1c, insulin, HOMA-IR, hs-CRP were higher in the lowest quartile than in the highest quartile (p<0.001). FT4 had effects on the waist circumference and triglyceride, but TSH had no effect on metabolic syndrome risk factors. The metabolic syndrome was lower in the highest quartile of FT4 than in its lowest quartile.

• Tunnel and Underground Space
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• v.26 no.2
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• pp.59-67
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• 2016

In this paper, we perform a numerical analysis to evaluate the potential of fault reactivation during gas production from hydrate bearing sediments and the moment magnitude of induced seismicity. For the numerical analysis, sequential coupling of TOUGH+Hydrate and FLAC3D was used and the change in effective stress and consequent geomechanical deformation including fault reactivation was simulated by assuming that Mohr-Coulomb shear resistance criterion is valid. From the test production simulation of 30 days, we showed that pore pressure reduction as well as effective stress change hardly induces the fault reactivation in the vicinity of a production well. We also investigated the influence of stress state conditions to a fault reactivation, and showed that normal fault stress regime, where vertical stress is relatively greater than horizontal, may have the largest potential for the reactivation. We tested one simulation that earthquake can be induced during gas production and calculated the moment magnitude of the seismicity. Our calculation presented that all the magnitudes from the calculation were negative values, which indicates that induced earthquakes can be grouped into micro-seismic and as small as hardly perceived by human beings. However, it should be noted that the current simulation was carried out using the highly simplified geometric model and assumptions such that the further simulations for a scheduled test production and commercial scale production considering complex geometric conditions may produce different results.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.2
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• pp.11-18
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• 1985

A row of bored piles has been used in several excavation works to retain the earth. This excavation bracing system has much effect on low-vibration and low-noise during construction. The system is also effective to provide protection to the adjacent existing ground and structures. For the purpose of establishment of a logical design method for the bored piles, first, a theoretical equation to estimate the resistance of piles is derived. Because arching action of soils between piles is considered in the equation, the characteristics of soils and the installation condition of piles would be considered logically from the beginning. Then a method is investigated to decide the interval ratio of piles. According to the method, the interval between piles can be decided from the information of the Peck's stability number, the coefficient of lateral earth pressure and the internal friction angle of soil. Finally, a design method is presented for the bored piles used for excavation work. In the presented design method, such factors as depth of excavation, pile diameter, interval between piles, pile length below bottom of excavation and pile stiffness, can be selected systematically.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.5
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• pp.407-415
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• 2008

The tubes in heat exchanger are typically made from copper alloy, stainless steel, carbon steel, titanium alloy material. type-439 ferritic stainless steel is ferromagnetic material, and furnish higher heat transfer rates than austenitic stainless steels and higher resistance to corrosion-induced flaws. Ferritic stainless steel can typically be found in low-pressure(LP) feedwater heaters and moisture separator reheaters(MSRs). LP feedwater heaters generally utilize thin wall type-439 stainless steel tubing, whereas MSRs typically employ a heavier wall tubing with integral fins. Service-induced damage can occur on the OD(outside diameter) surface of type-439 ferritic stainless steel tubing which is employed for MSRs tubing, and the most typical damage mechanism is vibration-induced tube-to-TSP(tube support plate) wear and fatigue cracking. The wear has been reported that occurs mainly on the OD surface. Accordingly, in this study, we have evaluated the flaw sizing capability of magnetic saturation eddy current technique using magnetic saturation probe and flawed specimen.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.5
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• pp.498-509
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• 2008

Reliability analyses of Level I, II and III for bearing capacity, overturning and sliding of quaywall are carried out to investigate their safety levels depending upon its failure modes, and sensitivity analyses of each design variable are performed to find their effects on safety levels of quaywall. Reliability indices was 1.416 for both level II and III for case study I, and with 2.201 and 1.880, respectively, for the case study II at the critical loading conditions. Thus we were able to know that Level II (FORM) approach is good enough to use in practical design. Generally, it was found that probabilities of failure of quaywall were higher for sliding and bearing capacity failure modes and lower for overturning failure mode. From sensitivity analyses, the most influential design variables to reliability index of quaywall were coefficient of friction, residual water pressure and resistance moment for the sliding, overturning and bearing capacity failure modes, respectively. Especially, the sensitivity of reliability index due to inertial force and dynamic water pressures, which include a large COV when earthquake occurs, did not change greatly.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.145-159
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• 2004

A mathematical model and its computer solution program were proposed to analyze the motion of contact lenses which are being subject to lid-blinking. The equation was derived by incorporating an acceleration induced lid's force exerting on the contact lens, the viscous damping resistance in the tear layer beneath the lens and the sliding frictional force between the lid and the contact lens surface into the formulation of differential equation describing the vibration. The model predicts the time-dependent displacement from the equilibrium postion during/after the blinking. During the blinking, as the time for the completion of one cycle of blinking decreases the off-the-equilibrium displacement of contact lens increases while the decrease of diameter in the contact cause the opposite effect. It is found that lid pressure exerting on the lens cause an insignificant lens displacement from the equilibrium position. After blinking the frequency of damped oscillation of contact lens decreases as the diameter of lens increases, due to the incresed surface while the reduced blinking time does not cause a significant frequency change. This is because that driving force for the contact lens movement posterior to blinking is the capillary-induced force not the lid force.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.2
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• pp.501-511
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• 2018

As a result of the recent revision of the 'Guideline for Installation and Management of Fire Prevention Facility in Road Tunnels', the thermal buoyancy has to be taken into account when calculating the capacity of jet fans for smoke control in tunnel fires. However, there is no detailed methodologies for considering thermal buoyancy, so further study is needed. In this study, the thermal buoyancy in the tunnel is calculated by 3-D numerical simulation to consider the thermal buoyancy in case of fire in tunnels, and the relationship between heat buoyancy and vehicle drag, And the method of calculating the capacity of the jet fan for smoke control in tunnels. According to the analysis results, heat buoyancy acts as a resistance force in the case of a down-slope tunnel, and the pressure rise of jet fan for smoke control is not simply determined by the value of heat buoyancy at the entrance of the tunnel and the value of the vehicle drag at the exit. And it is analyzed that it is necessary to carry out a comprehensive review according to the location of the fire vehicle in tunnels.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1345-1351
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• 2011

Vancomycin therapy failure due to the emergence of tolerance in pneumococci is increasing. The molecular mechanism of tolerance is not clear, but lytA and $pep^{27}$ are known to be involved. Our aim was to evaluate the expression of both genes in vancomycin-tolerant Streptococcus pneumoniae (VTSP) strains. Eleven VTSP strains from a total of 309 clinical isolates of S. pneumoniae from 1997 to 2006 were classified according to the criteria of Liu and Tomasz. All VTSP strains were evaluated for susceptibility according to CLSI criteria, serotype by the Quellung test, and clonality by PFGE. The expressions of lytA and $pep^{27}$ were analyzed in different growth phases by RT-PCR with and without vancomycin. Eighty-two percent of VTSP strains showed resistance to penicillin, and 100% were sensitive to vancomycin and cefotaxime. The most frequent serotypes of VTSP strains were 23F (4/11) and 6B (3/11). Clonal relationship was observed in only two strains. No significant changes were observed in $pep^{27}$ expression in the three phases of growth in VTSP strains with and without vancomycin. Interestingly, $pep^{27}$ expression in the stationary phase in the non-tolerant reference strain R6 was significantly higher. However, no significant differences in lytA expression were observed between VTSP and R6 strains during the phases of growth analyzed. The absence of changes in $pep^{27}$ expression in VTSP strains in the stationary phase may be related to their ability to tolerate high antibiotic concentrations, and thus, they survive and remain in the host under the antibiotic selective pressure reflected in therapeutic failure.

• The Korean Journal of Pharmacology
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• v.26 no.1
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• pp.25-33
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• 1990

The responsiveness of various arterial smooth muscles isolated from rabbit to peptide YY (PYY) and the calcium source responsible for the muscles to contract were studied in vitro. PYY contracted the muscle strips of femoral, basilar and common iliac arteries more sensitively than renal, superior mesenteric and common carotid arteries. Common carotid and renal arteries were less sensitive to PYY $(p{\leqslant}0.05)$ than to NE; and basilar artery was more sensitive to PYY$(p{\leqslant}0.01)$ than to NE. A calcium channel blocker, verapamil and an inhibitor of intracellular calcium release, 3, 4, 5-Trime-thoxybenzoic arid 8-(diethylamino)octyl ester [TMB-8] significantly $(p{\leqslant}0.001)$ suppressed the concentration-response of the strips from femoral artery to PYY. When both verapamil and TMB-8 existed in normal PSS, the concentration-response to PYY was inhibited almost completely; and a similar suppression was observed when the muscle was incubated in calcium-free, ethyleneglycol-bis-(beta-aminoethyl ether)N,N,N',N'-tetraacetic acid [EGTA] containing PSS. The results of these experiments suggest that increased PYY activity in circulation may result in the more sensitive increase in the intracranial vascular resistance and the cerebral arterial pressure than the increased sympathetic activity and that both intra- and extracellular calcium are to be utilized for the PYY-induced contraction on arterial smooth muscle.

• Journal of Yeungnam Medical Science
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• v.14 no.2
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• pp.350-358
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• 1997

We studied the effects of adding a single bolus(500 mg) of sodium thiopental to a continuous infusion of low-dose fentanyl on plasma beta-endorphin immunoreactivity(iBE) responses to cardiopulmonary bypass(CPB) in 28 patients undergoing elective coronary artery bypass grafting or valve procedures. Thiopental was injected just prior to the initiation of CPB. The iBE levels and the hemodynamic indices such, as mean arterial pressure, cardiac output and systemic vascular resistance were measured before CPB, at 30 min and again at 60 min after the initiation of the bypass. The results were as follows. After the initiation of CPB, iBE levels increased at 30 min and 60 min(P=0.006, P=0.004 respectively) in the control group, but not in the thiopental group. There were significant differences in the changes of iBE levels between the groups(F=8.7, G-G=0.002, P=0.001). The hemodynamic indices were similar in both groups. In conclusion, pretreatment with thiopental just before the initiation of CPB prevents the stress-induced beta-endorphin response to CPB.