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We aerosolized the Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis) bacteria and collected them on membrane filters. Then we generated air ions by applying a high voltage to a carbon fiber tip and applied them to the contaminated filters. The antibacterial efficiency was not significantly affected by the bacteria being Gram-positive or Gram-negative, however, negative ions showed a lower antibacterial efficiency than positive ions to both E. coli and S. epidermidis, even though the concentration of negative air ions was much higher than that of positive air ions. With a field emission scanning electron microscope (FE-SEM) images and fluorescence microscopy images using a LIVE/DEAD BacLight Bacterial Viability Kit, electrostatic disruption of the bacteria was found to be the dominant antibacterial effect.

This study evaluated the charging characteristics of a carbon fiber ionizer for PM2.5 and carried out particle capture laboratory tests after an ionizer was installed upstream of the media of an electret cabin air filter. When the ion concentration per particle (Ni) of the carbon fiber charger was 106 ions/cm3, the average charge numbers for each particle were 1.54, 0.88, and 0.49 at 0.6, 1.2, and 1.8 m/s of face velocity, respectively (the particle charging times, τ, were 167, 83, and 56 ms, respectively). For these face velocities, the PM2.5 removal efficiencies of the filter media were 69.3%, 65.2% and 62.2%, respectively, but increased to 80.4%, 71.2% and 65.5%, respectively, when the ionizer was turned on. The carbon fiber ionizer was then installed in front of an electret cabin filter in the air conditioning system of an automobile, after which field tests were performed at a roadside area. For the same Niτ used in the lab-scale tests, the effects of the carbon fiber ionizer on increasing PM2.5 %Reduction were mild as 9.4%, 4.0%, and 2.8% when the flow rates were at the second, fourth, and sixth levels, respectively (the face velocities were 0.6, 1.2, and 1.8 m/s, respectively). The PM2.5 %Reduction can be substantially increased by 20–21%, for a higher value of Niτ (=1.0×108 ions s/cm3), which is realized by increasing the power consumption of the carbon fiber ionizer.

Carbon fiber (CF) was catalytically activated with spark generated Pd aerosol nanoparticles. Metal (Ag, Au, Cu, and Pd) and alloy (Ni–P, Ni–Cu–P) electroless films were deposited on Pd aerosol activated CF using a range of deposition parameters including deposition rate in an electroless deposition bath. Sintering was applied to the alloy films on the CF to examine the crystallization behavior at 400 °C in a nitrogen atmosphere. Ni–Cu–P had a higher crystallinity than Ni–P after the treatment.

This paper reports the installation of a carbon fiber ionizer in front of a fibrous medium filter to enhance the removal of submicron aerosol particles and bioaerosols. Test particles (KCl) were classified with a size range of 50–600 nm using a differential mobility analyzer (DMA). The number concentration of the test particles was measured using a condensation particle counter (CPC). The average charge per particle was estimated by current measurements using an aerosol electrometer. At the face velocity of 0.5 m/s, the particle removal efficiency was 31.4% (for dp=100 nm) when the ionizers were not operating but increased to 35.7% and 46.9% at 1.6×1011ions/s and 6.4×1012ions/s with the ionizers, respectively. For the antibacterial tests, the test bioaerosols (E. coli) were aerosolized using a nebulizer and were deposited on the filter media for 5 minutes. After the deposited bioaerosols were exposed to unipolar air ions, they were incubated for 12 hours. The survival efficiency of E. coli was measured using a colony counting method. The survival fractions of E. coli exposed to positive air ions for 1, 5 and 10 minutes were 61.7%, 45.4% and 25.2%, respectively.

A plate-type dielectric barrier discharge (DBD) reactor was designed and tested for removal of gaseous toluene. The DBD reactor consisted of 9 parallel plate electrodes, four of which were grounded. An AC voltage of rectangular waveform (, ), was applied to the other five electrodes. The gaseous toluene passed through the DBD reactor and its concentration was measured by a real-time gas analyzer. The carbon monoxide (CO) and carbon dioxide () which were produced by decomposition of toluene in the DBD reactor, were sampled and analyzed by a micro gas chromatography. The maximum toluene removal efficiency was 51.4%.

A method for catalytic activation was introduced by producing palladium aerosol nanoparticles via spark generation and then thermophoretically depositing the particles onto a flexible polyimide substrate through a hole in pattern mask, resulting in a line (24 μm in width) and a square (136 μm × 136 μm) patterns. After annealing, the catalytically activated substrate was placed into a solution for electroless copper deposition. Finally, copper micropatterns of a line (35 μm in width) and a square (165 μm × 165 μm) were formed only on the activated regions of the substrate. Both patterns had the height of 1.6 μm. Keywords: Site-selective catalytic activation, Palladium aerosol nanoparticles, Electroless copper deposition, Micropatterning

There is great interest in the fabrication of micro- and nanopatterned metallic structures on substrates for a wide range of electronic, photonic, and magnetic devices. One of the most widely used techniques is the electroless deposition (ELD) of metal, which requires the surface activation of the substrates with a metal catalyst. This paper introduces a method of catalytic surface activation by producing platinum aerosol nanoparticles via spark generation and then thermophoretically depositing the particles onto a flexible polyimide (PI) substrate through the pattern hole of a mask. After annealing, the catalytically activated substrate is placed into a solution for electroless silver deposition. The silver is then formed only on the activated regions of the substrate. Silver line patterns having a width of 18 microm and a height of 1 microm are created with the ability to be effectively reproduced. The average value of the resistivities is approximately 6.8 mu Omega.cm, which is almost comparable to the theoretical resistivity of bulk silver (1.6 mu Omega.cm). Other silver micropatterns containing square dot array, line, line array, Y-branched line, and tapered line using different pattern masks are also demonstrated.

The collection efficiencies of submicron aerosol particles using a two-stage, dielectric barrier discharge (DBD) type electrostatic precipitator have been reported previously [ Byeon et al. (2006) . Collection of submicron particles by an electrostatic precipitator using a dielectric barrier discharge. Journal of Aerosol Science, 37, 1618–1628]. In this paper, the charge distributions of aerosol dioctyl sebacate (DOS) particles, which had a mobility equivalent diameter of 118, 175, and 241 nm and were charged in a DBD charger, were examined using a tandem differential mobility analyzer (TDMA) system at applied voltages of 9–11 kV and frequencies of 60–120 Hz. The mean number of elementary charges for positively or negatively charged particles increased slightly with increasing applied voltage or frequency. However, the number of elementary charges increased significantly with increasing particle size. At any applied voltage and frequency, the charge distributions of these particles of these sizes indicated asymmetric bipolar charging. The positive-to-negative charge ratios were 10.4, 4.7, and 3.0 for particle sizes of 118, 175, and 241 nm, respectively, at a DBD voltage and frequency was 9 kV and 60 Hz, respectively. Fluorometric analysis showed that average positive-to-negative charge ratios were 11.5, 4.9, and 3.7 for particle sizes of 118, 175, and 241 nm, which agrees well with the TDMA results. Further fluorometric analyses with larger particles (514 and 710 nm) and higher frequencies (1 and 2 kHz) showed that the positive-to-negative charge ratio reached almost unity with increasing particle size or frequency.

Pitch fibers were prepared from petroleum-derived isotropic pitch precursors using melt-blown spinning. Activated carbon fibers (ACF) were formed from pitch fibers and after stabilization, carbonization and steam thermal activation were then further activated with Pd–Sn catalytic nuclei in a single-step process. The activated ACF were then used as supporters in the specific, electroless deposition of fine copper particles. Field emission scanning electron microscopy-energy dispersive X-ray spectroscopy results showed that the ACF were uniformly coated with nearly pure fine copper particles, and the copper content on the ACF increased with deposition time. The amounts of copper on the ACF and their crystalline characteristics were analyzed using an inductively coupled plasma and a X-ray diffractometry, respectively. With the copper particles-deposited on the ACF, the removal of nitrogen monoxide (NO) for four different deposition times (5, 10, 15 and 20 min) was tested. Experiments on the removal of NO were carried out in a packed bed tubular reactor with various reaction temperatures ranging between 423 and 673 K. For all deposition times, the NO removal efficiency increased with increasing reaction temperature up to 673 K. The NO removal efficiency was the highest when the amount was Cu/ACF = 110 mg/g (deposition time of 5 min), however, decreased at Cu/ACF beyond 110 mg/g (deposition times of 10, 15, 20 min) due to the decreased adsorption as a result of the increased amount of copper.

Purpose: The purpose of this research was to evaluate the relationship between the 2007 Korean medical licensing examination (KMLE) and the 2006 Learning Objectives for Medical Students (LOMC) produced by the Association of Korean Medical Colleges’ Council of Deans. Methods: A total of 493 questions from the 2007 KMLE and the 2006 LOMC were used. The percentage and the frequency of each LOMC used in the 2007 KMLE were analyzed. The possibility of answering questions guided by the LOMC was analyzed. When questions could not be answered using the LOMC, we further categorized these questions into areas of medicine and specific causes. Results: A total of 669 (14.03%) learning objectives were used to solve questions from the 2007 KMLE. A learning objective was used a maximum of 5 times in the 2007 KMLE, and the percentages of one time, 2 times, 3 times, 4 times, and 5 times were 84.90%, 12.11%, 2.39%, 0.45%, and 0.15%, respectively. Four hundred six of 493 questions were solvable using the learning objectives, and 87 (17.65%) were not. When several steps were needed to solve a question, 15 questions (17.24%) could not be solved due to a lack of learning objectives for some of those steps. Overall, the 87 unsolvable questions were from internal medicine (37.9%), obstetrics & gynecology (14.9%), medical law (12.6%), pediatrics (10.3%), general surgery (9.2%), psychiatry (6.9%), and preventive medicine (1.1%). Questions difficult to solve specifically due to absent learning objectives were in the areas of treatment and procedure (29.67%), test and diagnosis (13.19%), symptoms (9.89%), pathophysiology (7.69%), complications (6.59%), and disease entity (6.59%). Conclusion: Discrepancy was observed between the 2007 KMLE and the 2006 LOMC. To solve this problem, the reorganization of both the KMLE and the LOMC based on a clear consensus of a primary care physician’s role is believed to be needed.

Silver aerosol nanoparticles generated by an atomizer were investigated as an antimicrobial agent against B. subtilis bioaerosols, a model for Gram-positive bacteria. The bioaerosols and silver aerosol nanoparticles were mixed in a test duct for 15 s and sampled on nutrient agar plates by an impactor. Peak concentrations of the silver aerosol nanoparticles at the mobility diameter of 80 nm were controlled from 1.5 × 105 to 1.0 × 106 particles/cm3, depending on the concentration of silver hydrosol nanoparticles. The maximal antimicrobial efficiency of silver aerosol nanoparticles was 76% under selected experimental conditions.

Even though activated carbon fiber (ACF) filters have been widely used in air cleaning for the removal of hazardous gaseous pollutants, because of their extended surface area and high adsorption capacity, bacteria may breed on the ACF filters as a result of their good biocompatibility; ACF filters can themselves become a source of bioaerosols. In this study, silver particles were coated onto an ACF filter, using an electroless deposition method and their efficacy for bioaerosol removal was tested. First, various surface analyses, including scanning electron microscopy, inductively coupled plasma and X-ray diffraction were carried out to characterize the prepared ACF filters. Filtration and antimicrobial tests were then performed on the filters. The results showed that the silver-deposited ACF filters were effective for the removal of bioaerosols by inhibition of the survival of microorganisms, whereas pristine ACF filters were not. Two bacteria, Bacillus subtilis and Escherichia coli, were completely inhibited within 10 and 60 min, respectively. Electroless silver deposition did not influence the physical characteristics of ACF filters such as pressure drop and filtration efficiency. The gas adsorptive ability of the silver-deposited ACF filter, as represented by the micropore specific surface area, decreased by about 20% compared to the pristine filter because of the blockage of the ACF micropores by silver particles. Therefore, the amount of silver particles on the ACF filters needs to be optimized to avoid excessive reduction of their adsorptive characteristics and to show effective antimicrobial activity.

Copper (Cu) and silver (Ag) known as antimicrobial materials were deposited on activated carbon fibers (ACF) by an electroless plating method. The metal deposited ACF filters were characterized by using SEM, EDX and XRD analyses. To verify the effects of metal deposition on the adsorptive characteristics of ACF filters, the specific surface area and pore structure were determined by BET equation and BJH method, respectively. The antimicrobial activities of metal deposited ACF filters against E. coli, P. fluorescens, B. subtilis and M. luteus were characterized by modified Kirby-Bauer method. By SEM-EDX and XRD analyses, it was confirmed that the electroless plating method was adequate for deposition of Cu and Ag on the surface of ACF filters. BET and BJH analyses showed that the micropore volume of metal plated ACF filters decreased compared to the pristine ACF filter. The inhibition zones, which represent the antimicrobial effects, were formed around the Cu and Ag deposited ACF filters whereas not in the case of pristine ACF.

Purpose Obstructive jaundice is a rare presentation, but is an ominous prognostic sign in patients undergoing surgery for a gastric carcinoma. Therefore, we investigated the prognosis of malignant obstructive jaundice following surgery for a gastric carcinoma. Materials and methods Thirty-eight patients, with an extrahepatic biliary obstruction due to a metastatic gastric carcinoma, were retrospectively studied to determine their demographics, clinical features, laboratory finding, pathological characteristics and survival. Results Between January 1996 and April 2000, 2401 patients underwent operations for gastric cancer, of which 38 (1.6%) were found to have obstructive jaundice. The mean age was 55.9 +/- 10.7 years, and the sex ratio (male: female) was 3.2: 1. The median interval between the previous gastrectomy and the presentation of jaundice was 10.1 8.9 months. The levels of total bilirubin and direct bilirubin were 16.5 +/- 6.5 and 12.0 +/- 4.4, respectively. The most common site of the obstruction was the common bile duct (65%). An antrumal location, poorly differentiated stage IV gastric cancer was common associated with obstructive jaundice. A percutaneous transhepatic biliary drainage was a commonly used treatment modality. When the clinical and laboratory findings were presented to a Cox regression analysis, the P values of the time interval and albumin were 0.019 and 0.057, respectively. Conclusion The time interval between a previous gastrectomy, the presentation of jaundice and albumin level were found to be independent risk factors for predicting the survival.

Although dielectric barrier discharge (DBD) in air has been used to clean hazardous air pollutants (HAPs) because of its high electron density and energy, its potential use as precharging dust aerosol particles is not well known. In this work, we measured the size distributions of bimodal submicron aerosol particles and estimated the collection efficiency of the particles for a hybrid two-stage electrostatic precipitator (ESP) comprised of a DBD charger as the particle charger and an ESP as charged particle collector. Nano-sized particles of NaCl (30–100 nm) and DOS (50–800 nm) were generated by evaporation–condensation and atomization, respectively. Various electrical and flow conditions were applied on the DBD charger: AC applied voltage of 9–11 kV, frequency of 60–120 Hz, and air flow rate of 60 – 180 L min - 1 ( 0.048 – 0.016 s of particle residence time). The particle collection efficiencies increased as the AC applied voltage increased at a fixed frequency–flow rate, whereas the efficiencies decreased as the frequency and flow rate increased at a fixed AC power–flow rate and a fixed AC applied voltage–frequency.

New equations of motion governing dynamic behavior of thin-walled curved beams were investigated based on the study of Kang and Yoo [Thin-walled curved beams, I: formulation of nonlinear equations, J. Eng. Mech., ASCE 120 (10) (1994) 2072-2101; Thin-walled curved beams, II: analytical solutions for buckling of arches, J. Eng. Mech., ASCE 120 (10) (1994) 2102-2125]. Explicit numerical expressions were derived to predict the complex dynamic behavior of the thin-walled curve beams. Stiffness and mass matrix of the curved beam element for finite element analyses were formulated to allow explicit evaluation of the dynamic behavior. The formulations were conducted using not only typical six degree of freedom but also additional warping degree of freedom at each node. This paper proved the validity and the convergence of the presented formulation using the curved beam element. The paper included comparisons of the natural frequencies of the thin-walled curved beams from the finite element formulations with those from other researchers' study. The presented formulation and the new equations are sufficiently accurate for use in study and evaluation of curved architectural structures and bridges.

Presented herein is a finite element formulation for free vibration analysis of horizontally curved steel I-girder bridges. Stiffness as well as mass matrices of the curved and the straight beam elements is formulated. Each node of both of them possesses seven degrees of freedom including the warping degree of freedom. The curved beam element is derived based on the Kang and Yoo's thin-walled curved beam theory in 1994. A computer program is developed to carry out free vibration analyses of the various bridges. Comparing with the frequencies using the general purpose program ABAQUS, the validity of the presented numerical formulation is shown. The numerical formulation is extensively applied to investigate free vibration characteristics of the bridges considering effects of the initial curvature, boundary condition, modeling method, and degrees of freedom of cross frame. Invaluable information which help practicing engineers better understand the vibration characteristics is provided.

A laboratory investigation was conducted to characterise and quantify fatigue life of continuously reinforced concrete pavement (CRCP) in Korea highway systems. Eight scale-sized specimens were made, based upon results of finite-element analyses and stress–strain curve comparisons. Rubber plates were used to simulate the cement-treated sub-base and the sub-grade below the concrete pavements. Initially static tests were performed to obtain magnitudes of static failure loads and to predict crack patterns before fatigue tests. The CRCP fatigue lives measured in the study were compared with the results of previous investigations by other researchers. The comparisons indicate that the fatigue lives of most specimens are very close to the results from equation of Vesic and Saxena (NCHRP Report 97, HRB, National Research Council, Washington, DC, 1970). The results obtained in the study can be used for maintenance and retrofit of the CRCP constructed in major Korea highway systems.

Zero-dimensional (0D) nanospheres, 1D nanocaterpillars, and 3D aggregates are produced from simple diblock copolymers containing polyacetylene (PA) via in situ nanoparticlization of conjugated polymers. The diblock copolymers are prepared by ring-opening metathesis polymerization via one-pot sequential addition of an endo-tricyclo[4.2.2.0]deca-3,9-diene (TD) and cyclooctatetraene. Initially, they spontaneously form nanospheres consisting of a PA core and PTD shell, and increasing the length of the PA block leads to the direct nanoparticlization of the higher-dimensional structures such as 1D and 3D aggregates because of the decreased effective volume ratio of the rigid PTD shell to the solvophobic PA core.

Even though conventional activated carbon has been widely used for removal of volatile organic compounds (VOC), problems associated with its short and unpredictable life spans need to be solved. The present study first introduces an idea of removing benzene, toluene and xylene (BTX) gas in a controllable way through carbon aerosol

Weight loss and malnutrition are common in cancer patients. Although weight loss is predominantly due to loss of fat mass, the morbidity risk is given by the decrease in muscle mass. The assessment of nutritional status is essential for a diagnosis of nutritional compromise and required for the multidisciplinary approach. Subjective global assessment (SGA) is made by the patients nutritional symptoms and weight loss. The objective assessment, a significant weight loss (>10%) for 6 months is considered an indicator of nutritional deficiency. The mean body index, body fat mass and body protein mass are decreased as cancer stage increases. The biochemical data of albumin, cholesterol, triglyceride, Zn, transferrin, total lymphocyte count are decreased in advanced cancer stage. Daily energy intake, cabohyderate and Vit B1 intake is decreased according to cancer stage. The patients are divided into three groups according to SGA. The three groups showed a significant difference in body weight, 1 month weight loss%, 6 month weight loss%, body mass index, mid arm circumference, albumin, energy intake, as well as carbohyderate intake protein and energy malnutrition. Nutritional assessment is of great importance because undernutrition has been shown to be associated with increase in stomach cancer associated morbidity and mortality. The authors concluded that nutritional assessment should be done in cancer patients preoperatively, and with adequate nutritional support, the morbidity and mortality would be decreased. (Korean J Gastroenterol 2013;61:186-190)

Purpose With an increase in life expectancy, more elderly patients are presenting with gastric cancer. As a result it is yet be resolved whether laparoscopy assisted distal gastrectomy is a suitable treatment for elderly patients with early gastric cancer. This study retrospectively compared surgical outcomes of laparoscopy assisted distal gastrectomy between elderly and nonelderly patients with gastric cancer. Materials and Methods The study group was comprised of 316 patients who underwent laparoscopy assisted distal gastrectomy between April 2005 and December 2010. Of these patients, 93 patients whose ages were 65 years or more were compared with 223 patients who were younger. Results There were no differences in the short term outcome or minor complication rate between the elderly patients and the nonelderly patients. The hospital stay was significantly longer and the major complication rate was significantly higher for the elderly patients compared with nonelderly patients. Conclusions Laparoscopy assisted distal gastrectomy for early gastric cancer in the elderly patients had comparable operation time and blood loss with the nonelderly group. However, the safety and advantage of laparoscopy assisted distal gastrectomy in the elderly patients need to be further studied in higher volume trials.

Metastatic leptomeningeal carcinomatosis is estimated to occur in 3% to 8% of solid carcinomas. The most common causes of leptomeningeal carcinomatosis are breast cancer, lung cancer and malignant melanoma. Leptomeningeal carcinomatosis associated with gastric cancer, especially in its early stages, is exceedingly rare. Its presenting symptoms include headache, nauseaand seizures. In this report, we describe a case of leptomeningeal metastasis that presented with early-stage gastric cancer. A 67-year-old woman with a history of early-stage gastric cancer in remission was admitted to our hospital with 3 days of headache and nausea. Her gastric cancer had been treated 29 months prior to presentation by a radical subtotal gastrectomy with a Billroth I anastomosis. She had an uneventful recovery until she was diagnosed with metastases to the left axilla and neck 26 months after surgery. Her presenting symptoms of headache and nausea prompted cytologic examination of the cerebrospinal fluid and measurement of tumor markers, which revealed metastatic leptomeningeal carcinomatosis from her gastric cancer. This report aims to raise awareness of the possibility that even early-stage gastric cancer can lead to leptomeningeal carcinomatosis.

Purpose: The use of 18F-2-deoxy-2-fluoro-D-glucose positron emission tomography-computed tomography as a routine preoperative modality is increasing for gastric cancer despite controversy with its usefulness in preoperative staging. In this study we aimed to determine the usefulness of preoperative positron emission tomography-computed tomography scans for staging of gastric cancer. Materials and Methods: We retrospectively analyzed 396 patients’ positron emission tomography-computed tomography scans acquired for preoperative staging from January to December 2009. Results: The sensitivity of positron emission tomography-computed tomography for detecting early gastric cancer was 20.7% and it was 74.2% for advanced gastric cancer. The size of the primary tumor was correlated with sensitivity, and there was a positive correlation between T stage and sensitivity. For regional lymph node metastasis, the sensitivity and specificity of the positron emission tomographycomputed tomography were 30.7% and 94.7%, respectively. There was no correlation between T stage and maximum standardized uptake value or between tumor markers and maximum standardized uptake value. Fluorodeoxyglucose uptake was detected by positron emission tomography-computed tomography in 24 lesions other than the primary tumors. Among them, nine cases were found to be malignant, including double primary cancers and metastatic cancers. Only two cases were detected purely by positron emission tomography-computed tomography. Conclusions: Positron emission tomography-computed tomography could be useful in detecting metastasis or another primary cancer for preoperative staging in gastric cancer patients, but not for T or N staging. More prospective studies are needed to determine whether positron emission tomography-computed tomography scans should be considered a routine preoperative imaging modality.

Recently, tailored and multidisciplinary treatment of gastric cancer was emerging in the field of clinical oncology. Gastric cancer is the most frequently diagnosed cancer in Korea. Surgery is the only possible curative procedure, and extensive gastrectomy and D2 lymph node dissection has been accepted as standard treatment in all gastric cancer patients until recently. In early gastric cancer, many researchers established the indications of limited surgery including endoscopic mucosal resection based on various well-collected retrospective data. Limited surgery and minimally invasive surgery contribute to quality of life in gastric cancer patients. In advanced gastric cancer, eastern surgeons believe that D2 lymph node dissection is standard treatment if done by credential surgeons in specialized centers despite of different opinion of western surgeon. In addition, adjuvant chemotherapy after good local control by D2 dissection has gained survival benefit rather than D2 dissection alone in randomized trials. In conclusion, present confronted issue is to establish tailored treatments of individualized patients through extent of disease in gastric cancer patients.

Safety verification against blast load is important in offshore structure for oil and gas development which have the high possibility of explosion accident. The structural response against blast is a nonlinear dynamic phenomenon, it is necessary the nonlinear dynamic analysis for accurate structural behavior. But it requires much more computing resource and manpower than conventional linear analysis. Therefore, simple approaches such as modified code check and Biggs’ simplified SDOF have been widely used for the structural verification. These approaches are very useful in design for simplicity and conservativeness. However, they don’t represent proper dynamic characteristics, thus sometimes they may cause excessively conservative. In this paper, the dynamic characteristic of structures beyond the yield point is studied by using nonlinear dynamic FE analysis and more safe and economic approach is suggested.Copyright © 2011 by ASME

We report the use of spark generation in an inert gas atmosphere to synthesize carbon-encapsulated metal nanoparticles (CEMNs) in a continuous aerosol manner using a metal (nickel, cobalt, iron)-graphite carbon electrode configuration without the use of a vacuum. The spark-generated particles consisted of CEMNs and carbonaceous aggregated debris. The outer layer of the CEMNs showed parallel fringes (ordered graphitic nanostructures) while the debris consisted of disordered nanostructures. Electron and X-ray diffraction showed that both metal and graphite in the CEMNs were the pure elements except for iron-carbon, which contained a carbide phase. Based on the order of the activation energies for carbon diffusion into a metal: iron-carbon (10.5-16.5 kcal mol(-1))cobalt-carbon (34.7 kcal mol(-1)) approximately nickel-carbon (33.0-34.8 kcal mol(-1)), it was concluded that carbide particles form more easily from elemental iron than nickel or cobalt. The metal-to-carbon mass fractions of the spark-generated particles from nickel (anode)-carbon (cathode), cobalt-carbon, and iron-carbon spark configurations were 18.7, 28.3, and 11.2%, respectively, while the mass fractions for the configurations of metal (cathode)-carbon (anode) were 6.4, 9.1, and 4.3%, respectively. Similarly, the yield of CEMNs from the metal (anode)-carbon (cathode) electrodes was higher (54, 61, and 53%) than that of metal (cathode)-carbon (anode) electrodes (18, 30, and 18%).

A lab-scale dielectric barrier discharge (DBD) reactor was fabricated, and gaseous and particulate contaminant removal tests were carried out under a range of DBD reactor operating conditions: applied voltage (5.0-8.5 kV), frequency (60-1000 Hz), upstream toluene concentration (50-200 ppm) and gas flow rate (1-5 L min(-1) or 0.48-0.096 s of gas residence time). The results suggested that the toluene removal efficiency (at 1 L min(-1), 100 ppm) increased (up to approximately 46%) either with increasing voltage (at 1000 Hz) or frequency (at 8.5 kV). The overall particle collection efficiency (at 1 L min(-1)) improved (up to approximately 60%) with increasing voltage (at 1000 Hz) whereas the penetration of the particles increased (up to approximately 40%) with increasing frequency (at 8.5 kV). The toluene removal efficiency (at 8.5 kV, 1000 Hz, 100 ppm) decreased (down to approximately 29%) with increasing gas flow rate while the particle collection efficiency decreased slightly (maintaining approximately 60%) regardless of the flow rate. In addition, the toluene removal efficiency (down to approximately 41%) and carbon dioxide selectivity (down to approximately 43%) decreased with increasing upstream toluene concentration (at 5 kV, 1000 Hz, 1 L min(-1)).

Abstract Korean shipyards have been leading the construction of newbuilt offshore structures in the last 10 years. HHI (Hyundai Heavy Industries Co.) is one of major EPC contractors and has successfully built several FPSOs, drilling rigs and FPUs intended for worldwide operation. HHI has established a strong reputation in construction as the world leading shipbuilding yard and has highly experienced workforce. Numerous novel methods enhancing HHI's competitiveness were employed in its recent endeavors. They include new construction methods (Ground Build Method), work on new technologies in collaboration with external research entities and participation in JIPs; the recent one focused on nonlinear impact fluid forces due to slamming, green water and viscous roll damping. HHI is also well established in the area of hull design for offshore industry. It has recently designed fatigue free FPSO using FMS (Fatigue Methodology Specification) co-developed by EMDC and DNV. HHI can respond with high degree of flexibility to client's needs as it owns extensive facilities (several dry docks) and has mastered effective project management methods. This paper summarizes the recent successful offshore projects from the perspective of accomplishment through collaboration. Introduction From the last decade, Korean shipyards have been at a No. 1 position in newbuilt FPSO market. As presented in Table 1, Korean shipyards had 16% and 9% share of FPSO hull and topside fabrication market respectively until 2007[1][2][3].

Size distributions of total airborne particles and bioaerosols were measured in a full-scale composting facility, using an optical particle counter and an agar-inserted six-stage impactor, respectively. Higher concentrations of total airborne particles and bioaerosols were detected at a sampling location near the screening process preceded by the composting process than at sampling locations in the composting process. At the sampling location near the screening process, the concentrations of total airborne particles were approximately 10(8)particles/m3 at the size of 0.3 microm and 10(5)particles/m3 at 6.2 microm. The concentration of bioaerosols was about 10(4)CFU/m3 in each stage of 7.0 microm (1st stage), 7.0-4.7 microm (2nd), 4.7-3.3 microm (3rd), 3.3-2.1 microm (4th), 2.1-1.1 microm (5th) and 1.1-0.65 microm (6th). Most of submicron particles smaller than 1 microm among the total airborne particles were believed to originate from the ambient air.

Nanoparticle susceptibility constants were defined and used to evaluate the antimicrobial characteristics of silver and copper nanoparticles against Escherichia coli and Bacillus subtilis. Reaction of copper nanoparticles of 100 nm with B. subtilis showed the highest susceptibility (Z=0.0734 mL/microg) whereas the reaction of silver nanoparticles of 40 nm with E. coli showed the lowest one (Z=0.0236 mL/microg).

The 105K COT (105,000 DWT Crude Oil Tanker) is being continuously constructed at the ground yard of HHI (Hyundai Heavy Industries), Ulsan, Korea as the first ground construction for ship type structures. She is loaded out transversely from the quayside by skidding onto the DBU (Double Barge Unit). The DBU will then be towed to a pre-determined site and ballasted down to float-off the 105K COT from the DBU. This paper describes the motions, mooring forces, collision possibilities and constraint forces of DBU / 105K COT during load-out, towing and float-off of the 105K COT.Copyright © 2005 by ASME

Purpose At present, a human epidermal growth factor receptor 2 (HER2)-based concept of tumor biology has been established, and trastuzumab (Herceptin®; Genentech/Roche, San Francisco, CA, USA), a monoclonal humanized antibody directed against HER2, is a pivotal agent for the management of HER2 positive (HER2+) metastatic breast cancer. It is also known that HER2 has a predictive value in gastric cancer; however, its association with the prognosis of this disease remains uncertain. The purpose of this study was to evaluate both the relationship between HER2 overexpression in the tumors of gastric cancer patients, and the prognosis of these patients who have had curative resection. Materials and Methods A total of 139 consecutive patients with gastric cancer who underwent surgery at the Kosin University Gospel Hospital between October 2011 and March 2012 were included in this retrospective study. All tumor samples were examined for HER2 expression by immunohistochemistry. A retrospective review of the medical records was conducted to determine the correlation between the presence of HER2 overexpression and clinicopathological factors. Results The HER2+ rate was 15.1%. HER2 overexpression was associated with histological grade (P=0.044) and Lauren classification (P=0.036). There was no significant difference in the 2-year overall survival between HER2+ and HER2- patients (P=0.396). Multivariate analysis showed that HER2 was not an independent prognostic factor. Conclusions HER2 overexpression in tumors was associated with histological grade and Lauren classification in gastric cancer patients with curative resection. However, HER2 was not an independent prognostic factor for gastric cancer in our study.

4105 Background: Benefit of quality of life made laparoscopic gastric cancer surgery attractive, but there are still concerns about laparoscopic lymph node dissection. The aim of this study was to evaluate a feasibility of laparoscopy-assisted distal gastrectomy (LADG) with D2 lymph node dissection compared with open distal gastrectomy (ODG) for advanced gastric cancer (AGC). Methods: Patients with cT2-T4a and cN0-2 (AJCC 7th staging system) distal gastric cancer were randomly assigned to LADG or ODG. The primary endpoint was the non-compliance rate of the lymph node dissection defined as rate of cases where there was more than one missing lymph node station according to the guidelines of the Japanese Research Society for Gastric Cancer lymph node grouping. Secondary endpoints were perioperative complications, changes of inflammatory and immunological parameters, postoperative hospital stay, and 3 year disease free survival. This trial was registered at ClinicalTrials.gov as NCT01088204. Results: Between Jun 2010 and Oct 2011,204 patients were randomly allocated and underwent either LADG (n=105) or ODG (n=99). 8 patients were excluded in the intention to treatment analysis because of protocol violation and patient’s withdrawal of permission, and finally 100 patients in LADG and 95 patients in ODG were analyzed. There were no significant differences of overall non-compliance rate of lymph node dissection between LADG and ODG groups; they were respectively 47.0% and 43.2%. (p=0.648). In the subgroup analysis according to the stratified risk groups, non-compliance rate in LADG was significantly higher than ODG (52.0% vs. 25.0%, p=0.043) for clinical stage III but it was not significantly different for stage II (46.2% vs. 48.9%, p=0.788). Intraoperative event rate was not significantly different between groups (LADG;6.0% and ODG;4.2%, p =0.748). Complications rate in early postoperative period up to 1 month was also not different between groups (LADG;17.0 %, ODG;18.8%, p=0.749). Conclusions: LADG was feasible in AGC compared with ODG, especially in clinical stage II in terms of non-compliance rate of D2 lymph node dissection and perioperative complications. Clinical trial information: NCT01088204.

To evaluate the treatment options for nephrotoxicity due to cisplatin combination chemotherapy.We retrospectively reviewed patients who had received cisplatin combination chemotherapy for gastric cancer between January 2002 and December 2008. We investigated patients who had shown acute renal failure (ARF), and examined their clinical characteristics, laboratory data, use of preventive measures, treatment cycles, the amount of cisplatin administered, recovery period, subsequent treatments, and renal status between the recovered and unrecovered groups.Forty-one of the 552 patients had serum creatinine (SCR) levels greater than 1.5 mg/dL. We found that pre-ARF SCR, ARF SCR, and ARF glomerular filtration rates were significantly associated with renal status post-ARF between the two groups (P = 0.008, 0.026, 0.026, respectively). On the receiver operating characteristic curve of these values, a 1.75 mg/dL ARF SCR value had 87.5% sensitivity and 84.8% specificity (P = 0.011).Cessation or reduction of chemotherapy should be considered for patients who have an elevation of SCR levels during cisplatin combination chemotherapy.

We report our case of laparoscopy-assisted distal gastrectomy with D1 + β lymph node dissection for a patient with early gastric cancer and laparoscopic cholecystectomy for gallstone with situs inversus totalis. A superficial elevated lesion was found on the lesser curvature of the antrum. The preoperative diagnosis was cStage IA (cT1, cN0, cH0, cP0, cM0). A 1 cm-sized gallstone was found in the fundus through upper abdominal ultrasound. A laparoscopy-assisted distal gastrectomy with standard D2 lymph node dissection for early gastric cancer and laparoscopic cholecystectomy was successfully performed by not shifting the monitor to the left and right and not changing operator's position without additional blood loss and time. The number of retrieved lymph nodes was 36. We have not found any abnormal course of blood vessels except for the right/left inversion. Billroth I reconstruction was performed through end-to-side anastomosis. Based on a histopathological examination, a 1.5 × 1.5 cm, submucosal (sm3), moderately differentiated adenocarcinoma (pT1, pN0, sH0, sP0, sM0, stage IA) was diagnosed. The postoperative course was favorable and the patient was discharged on postoperative day 7.

Mesenteric fibromatosis is a rare benign fibrous tumor that can occur from bowel mesentery of the retroperitoneum. It can infiltrate the surrounding structures and tends to recur locally even after resection but does not have metastatic capability. Mesenteric fibromatosis represents 8% of all intra-abdominal desmoid neoplasm. We experienced a case of mesenteric fibromatosis in a 50-year-old woman with a painless abdominal mass. An exploratory laparotomy was performed, and two large, small bowel mesenteric masses were found which were invading the transverse colon. The segment of the jejunum and transverse colon including the masses were resected widely and the pathologic report confirmed the diagnosis of fibromatosis. We reviewed the features of the mesenteric fibromatosis, that is, clinical, imaging, pathological, immunohistological features, and differential diagnosis and treatment of mesenteric fibromatosis.

Purpose: Laparoscopy assisted distal gastrectomy (LADG) has been accepted as the best standard operative technique in early gastric cancer. But, no predictive indicators of reconstructive procedure were reported. Analyzing the reconstructive procedure after LADG according to location of the lesion, we, herein, suggest an alternative. Methods: From May 2008 to May 2009, 55 patients with distal gastric cancer who underwent LADG were examined retrospectively. The group of 55 patients were assigned to two groups according to the reconstructive procedure undertaken: 41, Billroth I (BI); 14, Billroth II (BII). After measuring the distance between esophagogastric junction and tumor (ET) and between pyloric ring and tumor (PT), we found ET/(ET+PT). Results: The meanstandard error time of ET in BI and BII group was cm (5~38) and cm (6~30). The meanstandard error time of PT in BI and BII group was cm (2~36) and cm (8~40). The meanstandard error time of ET/(ET+PT) in BI and BII group was (16.1~95.0) and (13.0~75.0). ET, PT and ET/(ET+PT) were correlated with reconstructive procedure (P=0.007, 0.006, 0.005). In comparative analysis of correlation between ET and reconstructive procedure, 95% confidence level in BI and BII group is 18.0~22.9 cm and 10.0~17.7 cm; between PT and reconstructive procedure, 12.5~17.7 cm and 17.4~27.8 cm; and between ET/(ET+PT) and reconstructive procedure, 51.1~64.4% and 28.1~50.0%. Conclusion: In our study, predictive indicators of decision for reconstructive procedure in ET, PT, ET/(ET+PT) is 17.8~18.0 cm, 17.4~17.7 cm, 50.0~51.1%.

증례: 48세 남자 환자가 내원 하루 전에 발생한 복통을 동반한 3차례의 작은 종이컵 2컵 정도의 혈변을 주소로 내 원하였다. 환자는 3일 전에 과음을 하였고 2일 전부터 감기 약을 복용하였으며, 10년 전부터 고혈압으로 약을 복용하고 있었다. 신체검사에서 결막은 창백하지 않았고, 복부에 압 통이나 반발통은 없었다. 직장 수지 검사에서 촉지되는 이 상소견은 없었으나, 선홍색의 혈변이 묻어 나왔다. 생체징 후는 혈압 146/96 mmHg, 맥박 86회/분, 호흡수 20회/분, 체 온 37.2 C였고, 검사실 소견에서는 백혈구 7,100/mL, 헤모글 로빈 12.4 g/dL, 헤마토크리트 40%, 혈소판 223,000/mm 이었 고, 호중구는 62.1%, 림프구는 29.1%, 단핵구는 6.3%, 호산 구는 2.1%였다. PT는 12.3초(International Normalized Ratio 1.0)였다. 혈중 C-반응 단백은 0.03 mg/dL이었다. 환자는 내 원 다음날 대장 내시경을 시행하였고 상행 결장과 회장에서 응고된 출혈부분을 발견하고(Fig. 1A) 혈중 헤모글로빈의 감소가 없음을 확인했다. 그 다음날 충분한 대장의 청소를 시행 후 다시 시행한 대장 내시경 검사에서 충수의 입구에 서 출혈하는 부분을 발견하고(Fig. 1B) 외과로 전원하여 내 원 3일째에 충수돌기를 포함한 맹장 부분절제술을 시행하 였다(Fig. 2A). 수술 시 소견으로 충수돌기 주위에 약간의 액체 저류가 있었고, 충수돌기는 약 8 mm 정도의 직경으로 말단부의 염증소견이 그리고 맹장의 일부에 게실을 포함하 고 있음을 확인할 수 있었다(Fig. 2B). 충수에는 육안적으로 특이 사항이 없었다. 병리학소견으로는 충수돌기말단에 급 성 화농성 염증이 있었다.