• Journal of Gastric Cancer
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• v.15 no.2
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• pp.77-86
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• 2015

Laparoscopic proximal gastrectomy (LPG) is theoretically a superior choice of minimally-invasive surgery and function-preserving surgery for the treatment of proximal early gastric cancer (EGC) over procedures such as laparoscopic total gastrectomy (LTG), open total gastrectomy (OTG) and open proximal gastrectomy (OPG). However, LPG and OPG are not popular surgical options due to three main concerns: the first, oncological safety; the second, functional benefits; and the third, anastomosis-related late complications (reflux symptoms and anastomotic stricture). Numerous recent studies have concluded that OPG and LPG present similar oncological safety profiles and improved functional benefits when compared with OTG and LTG. While OPG with modified esophagogastrostomy does not provide satisfactory results, OPG with modified esophagojejunostomy showed similar rates of anastomosis-related late complications when compared to OTG. At this stage, no standard reconstruction method post-LPG exists in the clinical setting. We recently showed that LPG with double tract reconstruction (DTR) is a superior choice over LTG for proximal EGC in terms of maintaining body weight and preventing anemia. However, as there is no definitive evidence in favor of LPG with DTR, a randomized clinical trial comparing LPG with DTR to LTG was recommended. This trial, the Korean Laparoscopic Gastrointestinal Surgery Study-05 (NCT01433861), is expected to assist surgeons in choice of surgical approach and strategy for patients with proximal EGC.

• Molecules and Cells
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• v.26 no.1
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• pp.81-86
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• 2008

RNA interference (RNAi) was performed on several essential genes in the pinewood nematode Bursaphelenchus xylophilus, which causes pine wilt disease. Double-stranded RNA (dsRNA) was delivered to larvae or adult worms by soaking, electroporation, or microinjection. Soaking and electroporation of L2-L3 stage worms in solutions containing dsRNA for essential genes induced over 25% lethality after 5 days, and gene-specific phenotypes were observed. This lethality agreed with significant reductions of the targeted transcripts, as assayed by reverse-transcription coupled with real time PCR. Microinjection was the most efficient route as measured by the hatching rate of F1 embryos, which was reduced by 46%. When adult worms were soaked in dsRNA, lethality was induced in the F1 larvae, revealing the persistence of knockdown phenotypes. The penetrance of the RNAi phenotypes for essential genes was relatively low but consistent, indicating that RNAi should be useful for studying the in vivo functions of B. xylophilus gene products.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.84-92
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• 2000

A GaAs MESFET MMIC transmitter for 2.4 GHz wireless local loop handset is designed and fabricated. The transmitter consists of a double balanced active mixer and a two stage driver amplifier with voltage negative feedback. In particular, a pair of CS-CG(common source-common gate) structure compensates the reduction in dynamic range caused by unbalanced complementary IF input signals. And to suppress the leakage local power at RF port, the mixer is designed by using phase characteristic between the ports of MESFET. At the bias condition of 2.7 V and 55.2 mA, the fabricated MMIC transmitter with chip dimensions of $0.75\times1.75 mm^2$ obtains a measured conversion gain of 38.6 dB, output $P_{idB}$ of 11.6 dBm, and IMD3 at -5 dBm RF output power of -31.3 dBc. This transmitter is well suited for WLL handset.

• Journal of Gastric Cancer
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• v.11 no.4
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• pp.219-224
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• 2011

Purpose: The Roux en Y method has rarely been performed due to longer operation time and high risk of complication, despite several merits including prevention of bile reflux. We conducted a retrospective review of the result of Roux en Y reconstruction using two circular staplers after subtotal gastrectomy. Materials and Methods: From December 2008 to May 2009, a total of 26 patients underwent Roux en Y reconstruction using two circular staplers after subtotal gastrectomy, and seventy-two patients underwent Billroth-I reconstruction. Roux en Y anastomosis was performed using two circular staplers without hand sewing anastomosis. We compared clinicopathologic features and surgical outcomes between the two groups. All patients underwent gastrofiberscopy between six and twelve months after surgery to compare the bile reflux. Results: No significant differences in clinicopathologic findings were observed between the two groups, except for the rate of minimal invasive surgery (P=0.004) and cancer stage (P=0.002). No differences in the rate of morbidity (P=0.353) and admission duration (P=0.391) were observed between the two groups. Gastrofiberscopic findings showed a significant reduction of bile reflux in the remnant stomach in the Roux en Y group (P=0.019). Conclusions: When compared with Billroth-I reconstruction, Roux en Y reconstruction using the double stapler technique was found to reduce bile reflux in the remnant stomach without increasing postoperative morbidity. Based on these results, we planned to begin a randomized controlled clinical trial for comparison of Roux en Y reconstruction using this method with Billroth-I anastomosis.

• Structural Engineering and Mechanics
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• v.56 no.5
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• pp.813-833
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• 2015

Spherical reticulated shells are widely applied in structural engineering due to their good bearing capability and attractive appearance. Parametric modeling of spherical reticulated shells is the basis of internal analysis and optimization design. In the present study, generation methods of nodes and the corresponding connection methods of rod elements are proposed. Modeling programs are compiled by adopting the ANSYS Parametric Design Language (APDL). A shape optimization method based on the two-stage algorithm is presented, and the corresponding optimization program is compiled in FORTRAN environment. Shape optimization is carried out based on the objective function of the minimum total steel consumption and the restriction condition of strength, stiffness, slenderness ratio, stability. The shape optimization of four typical Schwedler spherical reticulated shells is calculated with the span of 30 m~80 m and rise to span ratio of 1/7~1/2. Compared with the shape optimization results, the variation rules of total steel consumption along with the span and rise to span ratio are discussed. The results show that: (1) The left and right rod-Schwedler spherical reticulated shell is the most optimized and should be preferentially adopted in structural engineering. (2) The left diagonal rod-Schwedler spherical reticulated shell is second only to left and right rod regarding the mechanical behavior and optimized results. It can be applied to medium and small-span structures. (3) Double slash rod-Schwedler spherical reticulated shell is advantageous in mechanical behavior but with the largest total weight. Thus, this type can be used in large-span structures as far as possible. (4) The mechanical performance of no latitudinal rod-Schwedler spherical reticulated shell is the worst and with the second largest weight. Thus, this spherical reticulated shell should not be adopted generally in engineering.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.1
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• pp.69-78
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• 2001

This paper presents the design and FPGA implementation of a FLEX PSP(Protocol Signal Processor) for the portable high speed paging system. In this approach, two algorithms are newly proposed for implementing the PSP which provides capabilities of the maximum 6,400bps at speed, high-channel throughput, real time error correction and an effective frame search function. One is an accurate symbol synchronization algorithm which is applied for synchronizing the interleaved 4-level bit symbols which are received at input stage of A/D converter, and the other is a modified fast decoding algorithm which is provided for realizing double error correction of (31,21)BCH signal. The PSP is composed of six functional modules, and each module is modelled in VHDL(VHSIC Hardware Description Language). Both functional simulation and logic synthesis have performed for the proposed PSP through the use of Synopsys$^{TM}$ tools on a Axil-320 Workstation, and where Altera 10K libraries are used for logic synthesis. From logic synthesis, we can see that the number of gates is about 2,631. For FPGA implementation, timing simulation is performed by using Altera MAX+ PLUS II, and its results will be also given. The PSP which is implemented in 6 FPGA devices on a PCB has been verified by means of Logic Analyzer.r.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.4
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• pp.299-307
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• 2003

Objectives: The present study was conducted to evaluate the mobile transposon-like element, clone MTi7 (MTi7) expression in the mouse ovary and to determine its role(s) in the mouse oocytes by RNA interference (RNAi). Methods: MTi7 mRNA expression was localized by in situ hybridization in day5 and adult ovaries. Double stranded RNA (dsRNA) was prepared for c-mos, a gene with known function as control, and the MTi7. Each dsRNA was microinjected into the germinal vesicle (GV) stage oocytes then oocyte maturation and intracellular changes were evaluated. Results: In situ hybridization analysis revealed that MTi7 mRNA localized to the oocyte cytoplasm from primordial to preovulatory follicles. After dsRNA injection, we found 43-54% GV arrest of microinjected GV oocytes with 68%-90% decrease in targeted c-mos or MTi7 mRNA. Conclusions: This is the first report of the oocyte-specific expression of the MTi7 mRNA. From results of RNAi for MTi7, we concluded that the MTi7 is involved in the germinal vesicle breakdown in GV oocytes, and MTi7 may be implicated with c-mos for its function. We report here that RNAi provides an outstanding approach to study the function of a gene with unknown functions.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.3
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• pp.151-159
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• 2018

Background: The pain involved in orthodontic treatments may involve inflammatory processes. This study evaluated the effect of using a naproxen patch for pain reduction in the separating stage of fixed orthodontic treatment. Methods: In this double-blind, randomized, controlled clinical trial of 35 orthodontic patients (age: 14-19 years) who had pain during separator placement, each patient randomly placed naproxen and placebo patches in the first permanent molar region, in opposite quadrants of the same jaw. Patches were replaced every 8 hours until 3 days after separator placement. Patients recorded their pain perception at 2, 6, and 24 hours, and on days 2 (6 PM), 3 (10 AM and 6 PM), and 7 (10 AM and 6 PM), using a visual analog scale. Mean pain scores were compared for the two patches, and effects of sex and age thereon determined. Results: Data from 29 patients (21 girls, eight boys) were analyzed. Mean pain values decreased over time for both patches (P < 0.001). Recorded pain did not differ significantly between the sexes (P = 0.059) or between those aged <16 and those ${\geq}16years$ (P = 0.106). Mean pain recorded with naproxen patches was statistically significantly less than that with placebo patches at all time points (P = 0.004). Conclusion: The naproxen patch was more efficient than the placebo patch for reducing pain at all time points. The highest pain score was recorded at 6 hours, and the least pain was recorded at the $7^{th}$ day after separator placement.

• Journal of the Korean Society of Combustion
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• v.19 no.1
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• pp.17-28
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• 2014

In this study, the laminar burning velocity of syngas fuel($H_2/CO$) and flame structure with various hydrogen contents were studied using both experimental measurements and detailed kinetic analysis. The laminar burning velocities were measured by the angle method of Bunsen flame configuration and the numerical calculations including chemical kinetic analysis were made using CHEMKIN Package with USC-Mech II. A wide range of syngas mixture compositions such as $H_2$ : CO = 10 : 90, 25 : 75, 50 : 50, 75:25 and equivalence ratios from lean condition of 0.5 to rich condition of 5.0 have been considered. The experimental results of burning velocity were in good agreement with previous other research data and numerical simulation. Also, it was shown that the experimental measurements of laminar burning velocity linearly increased with the increment of $H_2$ content although the burning velocity of hydrogen is faster than the carbon monoxide above 10 times. This phenomenon is attributed to the rapid production of hydrogen related radicals such as H radical at the early stage of combustion, which is confirmed the linear increase of radical concentrations on kinetic analysis. Particular concerns in this study are the characteristics of burning velocity and flame structure different from lean condition for rich condition. The decrease of OH radicals and double peaks are observed with $H_2$ content in rich condition once $H_2$ fraction exceeds over threshold.

• Journal of the Korean Wood Science and Technology
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• v.45 no.2
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• pp.147-158
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• 2017

Among the energy consumption in building, the heating energy takes the largest part. Therefore, it is important to minimize the heat energy loss in building for the reduction of overall energy use in construction. The most important points for the minimization of energy loss in building are insulation and airtightness. Especially, in wood houses, airtightness is very important for energy saving as well as increase of durability. However, the researches on airtightness of wood buildings have been started recently and are very deficient especially in Korea. In this study, air leakage properties and airtightness performance were evaluated for light-frame wood houses built in Daejeon and Chungnam area. Total 7 houses were evaluated, among which four houses (Case 1 to Case 4) were in the construction stage before interior finish and the other three houses (Case 5 to Case 7) were after completion of construction work. The tests for airtightness were conducted by pressurization-depressurization method, and the factors included in the measurements includes air leakage rate at 50 Pa (CMH50), air change rate at 50 Pa (ACH50), equivalent leakage area (EqLA) and EqLA per floor area. As a result of this study, key air leakage points in wood houses were found to be the gaps between floor and wall, the holes for wiring and plumbing, the double glasses windows and the entrance doors. The average value of ACH50 for the houses after completion of construction work was $3.5h^{-1}$ that was similar to Europe standard ($3.0h^{-1}$). ACH50 was proportional to EqLA per floor area but inversely proportional to the internal volume, the net floor area and the area of window.