• YAKHAK HOEJI
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• v.53 no.5
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• pp.286-292
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• 2009

In this study, we investigated the anti-obese activity of HPJ extract in C57BL/6J mice. The C57BL/6J mice were randomly divided into five groups: normal control group (Con), high fat diet control group (HFD), treatment groups with HPJ at 125 mg/kg (HPJ125), 250 mg/kg (HPJ250), or 500 mg/kg (HPJ500). To induce an obesity, mice were fed by a high fat diet for 6 weeks, and mice were administered with HPJ extract once a day for 8 weeks. At the end of treatment, we examined the effect of HPJ extract on body weight, plasma lipid, and lipogenic enzymes. HPJ extract was found to lower whole body and epididymal adipose tissue weights and lowered plasma levels of glucose, insulin, triglyceride (TG), total cholesterol (TC), non-esterified fatty acid (NEFA) and leptin, compared to those in HFD group. Histological analyses of the liver and fat tissues of mice treated with HPJ extract revealed significantly decreased number of lipid droplets and decreased size of adipocytes compared to the HFD group. In addition, HPJ extract preserved the morphological integrity of pancreatic islets. To elucidate an action mechanism of HPJ extract, Western blot and RT-PCR were performed using epididymal adipose tissues. HPJ extract up-regulated the levels of phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and its substrate, acetyl-CoA carboxylasse (ACC). HPJ extract also attenuated lipogenic gene expressions of sterol regulatory element-binding protein $1{\alpha}$ (SREBP$1{\alpha}$), fatty acid synthase (FAS), sterol-CoA desaturase 1 (SCD1) and glycerol-3-phosphate acyltransferase (GPAT) in dose-dependent manners. In contrast, expressions of lipolytic genes such as peroxisome proliferator-activated receptor-$\alpha$ (PPAR-${\alpha}$) and CD36, and fatty acid $\beta$-oxidation gene, carnitine palmitoyltransferase-1 (CPT-1) were increased. These results suggest that HPJ extract ameliorates obesity through inhibiting synthesis of lipogenic enzymes as well as stimulating fatty acid oxidation resulting from activation of AMPK, and HPJ extract could be developed as a potential therapeutic agent for obese patients.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.10 s.352
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• pp.79-89
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• 2006

TCP is the most widely used transport protocol in Internet applications that guarantees a reliable data transfer. But, in the wireless multi-hop networks, TCP performance is degraded because it is designed for wired networks. The main reasons of TCP performance degradation are contention for wireless medium at the MAC layer, hidden terminal problem, exposed terminal problem, packet losses in the link layer, unfairness problem, reordering problem caused by path disconnection, bandwidth waste caused by exponential backoff of retransmission timer due to node's mobility and so on. Specially, in the mobile ad-hoc networks, discrepancy between a station's transmission range and interference range produces hidden terminal problem that decreases TCP performance greatly by limiting simultaneous transmission at a time. In this paper, we propose a new MAC algorithm for mobile ad-hoc networks to solve the problem that a node can not transmit and just increase CW by hidden terminal. In the IEEE 802.11 MAC DCF, a node increases CW exponentially when it fails to transmit, but the proposed algorithm, changes CW adaptively according to the reason of failure so we get a TCP performance enhancement. We show by ns-2 simulation that the proposed algorithm enhances the TCP performance by fairly distributing the transmission opportunity to the failed nodes by hidden terminal problems.

• Clean Technology
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• v.26 no.1
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• pp.30-38
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• 2020

The kinetic and thermodynamic parameters of Acid Red 66, adsorbed by granular activated carbon, were investigated on areas of initial concentration, contact time, and temperature. The adsorption equilibrium data were applied to Langmuir, Freundlich, Temkin, Redlich-Peterson, and Temkin isotherms. The agreement was found to be the highest in the Freundlich model. From the determined Freundlich separation factor (1/n = 0.125 ~ 0.232), the adsorption of Acid Red 66 by granular activated carbon could be employed as an effective treatment method. Temkin's constant related to adsorption heat (B_T = 2.147 ~ 2.562 J mol^-1) showed that this process was physical adsorption. From kinetic experiments, the adsorption process followed the pseudo-second order model with good agreement. The results of the intraparticle diffusion equation showed that the inclination of the second straight line representing the intraparticle diffusion was smaller than that of the first straight line representing the boundary layer diffusion. Therefore, it was confirmed that intraparticle diffusion was the rate-controlling step. From thermodynamic experiments, the activation energy was determined as 35.23 kJ mol^-1, indicating that the adsorption of Acid Red 66 was physical adsorption. The negative Gibbs free energy change (ΔG = -0.548 ~ -7.802 kJ mol^-1) and the positive enthalpy change (ΔH = +109.112 kJ mol^-1) indicated the spontaneous and endothermic nature of the adsorption process, respectively. The isosteric heat of adsorption increased with the increase of surface loading, indicating lateral interactions between the adsorbed dye molecules.

• Korean Journal of Construction Engineering and Management
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• v.11 no.5
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• pp.65-74
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• 2010

The design with construction knowledge and experience can eliminate inefficiency in the process of construction and improve productivity in all phase of construction project. To utilize constructability knowledge most effectively in design phase, the information must be made available to the design team at the proper point in time. Current methods for effective utilization of constructability knowledge have focused on the structuralization of constructability knowledge such as checklist, which lack the consideration of the proper point in time. However, constructability knowledge which is used at the inapposite point in time consequently leads to unnecessary rework. To minimize this inefficiency and improve productivity, project manager needs to consider the design process and know what constructability knowledge is required for specific design activities. This paper therefore presents a design process management using Dependency Structure Matrix (DSM) that focus on information flows between design activities and constructability knowledge. We expect that the results of this paper will support that design process management become comprehensive management related to every phase of construction project beyond design review or inspection in design phase, and be used as a basis of the integration of design and construction.

• Journal of the Korean earth science society
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• v.18 no.6
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• pp.553-558
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• 1997

Colorless and transparent cubic zirconia($Zr_{0.73}Y_{0.27}O_{1.87}$) crystal has been synthesized by the Bridgman-Stock-bager method(also called Skull melting method). $Y_2O_3$ is used as stabilizer. The crystal shows a vitreous luster with a slight oily appearance. Under a polarizing microscope, it shows isotropic nature with no appreciable anisotropism. Mohs hardness value is measured to be $8{\sim}8\frac{1}{2}$ and specific gravity 5.85. Under ultraviolet light it shows a faint white glow. The crystal structure of yttria stabilized zirconia was determined, using single crystal X-ray diffraction techniques to be a cubic symmetry, space group $Fm\overline{3}m({O^5}_h)$ with $a=5.1552(5){\AA}$, $V=136.99(5){\AA}^3$, Z=4, and R=0.0488 for 29 unique reflections. Each zirconium atom is at the center of eight oxygen atoms situated at the corners of a surrounding cube and each oxygen atom is at the center of a tetrahedron of zirconium atoms. So a coordination of 8:4 holds in the structure.

• Applied Chemistry for Engineering
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• v.24 no.3
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• pp.327-332
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• 2013

Batch experiments were carried out for adsorption equilibrium, kinetics and thermodynamic parameters of the brilliant brown R onto granular activated carbon. The operating variables studied were the initial dye concentration, contact time and temperature. Experimental equilibrium adsorption data were fitted to Langmuir and Freundlich adsorption isotherm by linear regression method. The equilibrium process was well described by Freundlich isotherm model and from the determined separation factor (1/n), granular activated carbon could be employed as an effective treatment for the removal of bismarck brown R. From kinetic experiments, the adsorption processes were found to confirm the pseudo second order model with a good correlation and the adsorption rate constant ($k_2$) increased with increasing adsorption temperature. Thermodynamic parameters like the activation energy, change of Gibbs free energy, enthalpy, and entropy were also calculated to predict the nature of adsorption in the temperature range of 298~318 K. The activation energy was determined as 8.73 kJ/mol for 100 mg/L. It was found that the adsorption of bismarck brown R on the granular activated carbon was physical process. The negative Gibbs free energy change (${\Delta}G$ = -2.59~-4.92 kJ/mol) and the positive enthalpy change (${\Delta}H$ = +26.34 kJ/mol) are indicative of the spontaneous and endothermic nature of the adsorption process.

• Clinics in Shoulder and Elbow
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• v.6 no.1
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• pp.72-79
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• 2003

Purpose: To compare the results of arthroscopic rotator cuff repair and subacromial decompression in partial thickness rotator cuff tear (PTRCT) with those in full thickness rotator cuff tear (FTRCT). Subjects and method: Of the 46 patients who were rested of the rotator cuff tear based on the operational findings, 42 patients who were able to receive a serial follow-up for 2 years were selected as the study subjects. The average age of the patients at the time of the operation was 55 years, and the mean duration of the follow-up was 34 months. The subjects included 22 cases of PTRCT and 20 cases of FTRCT. In terms of rotator cuff repair, the average number of tendon to tendon repair (TTR) was 1 in both PTRCT and FTRCT, and that of tendon to bone repair (TBR) was 1 and 3 in PTRCT and FTRCT, respectively. The average number of use of suture anchor was 1 and 2 in PTRCT and FTRCT, respectively. The level of shoulder pain and function of the subjects were measured using shoulder functional evaluation score of American shoulder and elbow society (ASES score) at before and 2 years following the operation. Results: At the final follow-up following the operation, PTRCT group showed changes in scores from 7.2 to 0.9 on average pain score and 34 to 91 on ASES score, whereas FTRCT group showed changes in scores from 7.6 to 1.2 on pain score and 29 to 88 on ASES score. There were no significant differences between the two groups (P > 0.05). The average range of motion of shoulder significantly increased in both groups at the final follow-up in comparison with the pre-operative time point. The evaluation at the final follow-up showed that 93% of the total subjects showed good or excellent results, and 95％ showed satisfactory results from the procedure with regard to pain reduction and functional outcomes. Two cases of the 3 fair results were caused by acromioclavicular arthritis. Conclusion: It may be anticipated that arthroscopic rotator cuff repair and subacromial decompression may bring satisfactory post-operative outcomes in both PTRCT and FTRCT on pain relief and functional recovery. However, careful preoperative examination of the acromioclavicular joint is critical to avoid failures of these procedures.

• Tuberculosis and Respiratory Diseases
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• v.57 no.6
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• pp.604-608
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• 2004

A 47-year-old-man was admitted to the emergency department with dyspnea, right pleuritic pain, and high fevers for 3 days. He had a nonproductive cough that exacerbated the chest pain. A clinical examination revealed distressed and slightly tachypneic patient, with blood pressure of 110/90 mmHg, temperature of $39^{\circ}C$, pulse of 90 beats/min, respiratory rate of 24 breaths/min. A chest examination showed significantly diminished breath sounds in the right lung with dullness to percussion. Laboratory investigation demonstrated leukocytosis and a raised C-reactive protein. The results of arterial blood gas analysis revealed moderate hypoxemia. A radiograph and a CT scan of the chest showed extensive consolidation with multifocal low densities, and pleural effusion in the right lung. A diagnostic thoracentesis revealed straw-colored fluid, which was found to be a neutrophil-predominant exudate. At 7 days after admission, the clinical symptoms had not improved and the temperature was still $39^{\circ}C$ despite the aggressive therapy of community-acquired pneumonia. After comprehensive history taking, we realized then that he accidentally aspirated kerosene while siphoning from fuel tank to put into the boiler 3 days ago. Bronchoscopy with bronchial washings could be successful in establishing the diagnosis of hydrocarbon pneumonitis by demonstration of a high lipid-laden macrophage index. Thereafter, the symptoms and radiographic opacities gradually improved, and he was discharged several days later.

• Tuberculosis and Respiratory Diseases
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• v.66 no.1
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• pp.27-32
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• 2009

Background: The management of patients with lung cancer has improved recently, and many of them will require admission to the medical intensive care unit (MICU). The aim of this study was to examine the clinical characteristics and to identify risk factors for mortality in patients with lung cancer admitted to the MICU. Methods: We conducted retrospective analysis on 88 patients with lung cancer admitted to the MICU between April 2004 and March 2008. Results: Of the 88 patients (mean age, 66 years), 71 patients (80.7%) had non-small cell lung cancer and 17 patients (19.3%) had small cell lung cancer. Distant metastasis were present in 79 patients (89.8%). The main reasons for MICU admission were acute respiratory failure (77.3%), sepsis (11.4%), and central nervous system dysfunction (4.5%). Mechanical ventilation was used in 54 patients (61.4%). Acute Physiology and Chronic Health Evaluation (APACHE) II score, length of MICU stay, need for mechanical ventilation, source of MICU admission were correlated with MICU mortality. The type of lung cancer and metastasis were not predictive factors of death in MICU. Conclusion: Most common reason for ICU admission was acute respiratory failure. Mortality rate of lung cancer patients admitted to the MICU was 65.9%. APACHE II score, length of ICU stay, need for mechanical ventilation, source of MICU admission were predicted factors of death in the MICU.

• Journal of Korean Neurosurgical Society
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• v.30 no.10
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• pp.1200-1209
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• 2001

Objective : A thorough understanding of the related venous structure is mandatory for successful removal of the petroclival meningiomas. This study was planned to investigate the guideline for safe ligation and incision of transverse or sigmoid sinuses and the importance of drainage pattern of vein of $Labb{\acute{e}}$ in surgical removal of petroclival meningiomas. Patients and Methods : The authors reviewed the venogram of the consecutive 37 cases of petroclival meningiomas and retrospectively analyzed their surgical findings. The drainage pattern of confluence of Herophili was classified as Type A(confluent & equal on both sides), Type B(confluent & non-dominant on tumor side), Type C(confluent & dominant on tumor side) and Type D(unilateral drainage only) as these findings gave the information on safe ligation and resection of the sinus. Usefulness of intraoperative test clamping of sinus for safe ligation was also reviewed. The vein of $Labb{\acute{e}}$ was analyzed with respect to its draining point and its collaterals to other superficial veins. Results : Contraindications of the sinus ligation and resection according to the drainage pattern at the confluence of Herophili were Type C(n=10, 27%)and Type D(n=4, 11%). Patients with Type A(n=12, 32%)and Type B(n=11, 30%) were tolerable to sinus ligation ipsilateral to tumor, if the test clamping proved to be safe. Identification of no brain swelling, after intraoperative test clamping of the sinus for more than 30 minutes performed in 7 out of 11 cases, was a reliable indicator of safe sinus ligation. The drainage pattern of the vein of $Labb{\acute{e}}$, especially low-lying type, could predict the possibility of postoperative hemorrhage and infarction. Its drainage into tentorium or superior petrosal sinus, however, made the transtentorial approach impossible, leading to restricted operative field. Conclusion : For a successful removal of the petroclival meningiomas preoperative venogram should be examined carefully. The extent of exposure in a planned approach can be estimated by analyzing the variation of sinuses and the drainage pattern of vein of $Labb{\acute{e}}$.