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The effect of cold rolling on hydrogen embrittlement in stable 18Cr–1Mn–11Ni-0.15 N austenitic stainless steels was investigated. Alloy plates were cold-rolled to 15% or 30% reduction, then pre-charged with hydrogen and subjected to tensile testing with slow strain rate. Hydrogen-induced degradation of tensile elongation became increasingly severe with the increase in the degree of cold rolling. During cold rolling, deformation twins with various orientations were actively generated, and twins with specific orientations were vulnerable to hydrogen-induced cracking. Cold rolling also increased the density of defects, and thereby facilitated penetration of hydrogen into the steels. The combination of cracks generated at the twin boundaries, and the promoted hydrogen diffusion caused severe hydrogen embrittlement in the cold-rolled steels.

We report on successful control of the density of carbon nanowalls (CNWs) synthesized using radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) employing CH4/H2 plasma, by varying the total pressure and discharge power during growth. As the total pressure was decreased or the power was increased, the density of CNWs decreased in conjunction with an increase in the H atom density measured using actinometric optical emission spectroscopy. The electrical conductivity of the films was found to be determined by the number of CNWs per unit length, i.e., the linear density. We demonstrated that the electrical properties could be controlled while maintaining the crystal quality and chemical bonding state of the synthesized CNWs in the RI-PECVD.

RATIONALE Liver transplantation is an increasingly common treatment for patients with liver cirrhosis or hepatocellular carcinoma. Liver transplantation in patients with heart disease can pose a significant challenge to the transplant teams. PATIENT CONCERNS A 46-year-old woman was diagnosed with hepatitis B virus-related hepatocellular carcinoma 3 years ago and had received 3 times transarterial chemoembolization. DIAGNOSES The patient was diagnosed as end-stage liver disease due to hepatocellular carcinoma and was scheduled to undergo living-donor liver transplantation. The preoperative echocardiogram revealed mass in the right atrium and the inferior vena cava. INTERVENTIONS The patient underwent mass removal under cardiopulmonary bypass followed by liver transplantation. OUTCOMES A month later, she was discharged without any complications. LESSONS There have only been a few reported cases of anesthetic liver transplantation after a cardiopulmonary bypass. The successful experience described in this case report suggests that some patients may be eligible to undergo a liver transplantation after a cardiopulmonary bypass.

Background and Aim We analyzed the characteristics of gastrointestinal neuroendocrine tumors and examined the outcomes and safety of modalities in rectal neuroendocrine tumors. Methods Between 2007 and 2011, a total of 91 patients with gastrointestinal neuroendocrine tumors were retrospectively reviewed in terms of the characteristics of tumors. Results Sixty-six patients had rectal neuroendocrine tumors and underwent endoscopic mucosal resection (EMR, n = 29), endoscopic submucosal dissection (ESD, n = 23), or transanal endoscopic microsurgery (TEM, n = 14). The complete resection rate was higher in the ESD group (82.7%) and in the TEM group (100%) compared to the EMR group (65.5%) (P

Background/Aims Ciprofloxacin is considered to be a safe and effective treatment for acute infectious colitis. However, this drug may cause drug-induced pancreatitis, albeit rarely. Methods From March 2007 to February 2012, we studied 227 patients who were hospitalized for infectious colitis at St. Mary's Hospital. All of the patients received ciprofloxacin therapy for the treatment of infectious colitis. We observed a few cases of rare adverse events, including ciprofloxacin-induced acute pancreatitis diagnosed based on the Naranjo algorithm. Results During ciprofloxacin therapy, seven of 227 patients (3.1%) developed rare pancreatitis as defined by the Naranjo algorithm; pancreatic enzyme activity was sporadically elevated with ciprofloxacin use. After ciprofloxacin administration, the average interval until the development of pancreatitis was 5.5 days (range, 4 to 7 days). On abdominal computed tomography, pancreatic swelling and homogenous enhancement was noted in three of seven patients. Complicating acute pancreatitis was gradually but completely resolved after cessation of ciprofloxacin administration. The mean recovery time was 11.3 days (range, 8 to 15 days). Conclusions We observed that ciprofloxacin-induced pancreatitis may occur with an incidence of approximately 3%. Ciprofloxacin-induced pancreatitis presents a short latency, suggesting an idiosyncratic hypersensitivity reaction. Practitioners should be aware that drug-induced pancreatitis can occur during ciprofloxacin therapy.

This work presents a W band frequency synthesizer which is composed of 26 GHz VCO, Phase Locked Loop and frequency tripler using 65 nm RF CMOS process. Frequency tuning range of 26 GHz VCO covers the band from 22.8~26.8 GHz and final output frequency of the tripler is from 74 to 75.6 GHz. The fabricated frequency synthesizer consumes 75.6 mW and its phase noise is -75 dBc/Hz at 1 MHz offset, -101 dBc/Hz 10 MHz offset respectively.

In recent system-on-chip (SoC) designs, several hundred embedded memory cores have occupied the largest portion of the chip area. Therefore, the yield of SoCs is strongly dependent on the yield of the embedded memory cores. If all memories had built-in self repair (BISR) with optimal repair rates, the area overhead would be very large. A bit-map sharing method using a memory grouping is proposed to reduce the area overhead. Since the bit-map memory occupies the largest portion of the area of the built-in redundancy analysis (BIRA), the proposed bit-map sharing method can greatly reduce the area overhead of the BIRA. Based on the experimental results, the proposed method can reduce the area overhead by about 80%.

Dual-wavelength holography has a better axial range than single-wavelength holography, allowing unambiguous phase imaging. Partial coherence sources reduce coherent noise, resulting in improved reconstructed images. We measured a ball-grid array using dual-wavelength holography with partial coherence sources. This holography method is useful for measurement samples that exhibit coherence noise and have a step height larger than the single wavelength used in holography.

In this paper we have applied self-reference hologram to DHM (digital holography microscopy) to remove phase aberration. We have constructed an off-axis reflection- type digital holography microscope. We have extracted a low spatial frequency hologram from the conjugated hologram and used it as a reference hologram. Experimentally we show that distortion of image and aberration of phase in a measurement system are removed using the self-reference hologram.

For polymer electrolyte fuel cell (PEFC) applications, effects of Pt-nanoparticle-supported three-dimensional carbon nanostructures, i.e., carbon nanowalls (Pt/CNWs), on electrochemical characteristics were determined by alternating current (AC) impedance analysis of resistive elements, which contribute to the oxygen reduction reaction (ORR). CNWs were fabricated by radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD), and Pt catalysts were formed on the template of CNWs by supercritical fluid metalorganic chemical fluid deposition (SCF-MOCFD). CNWs of different wall densities were synthesized during RI-PECVD by varying the deposition pressure. The resistive elements can be consisted of three regions with different corresponding frequencies, and the resistive elements of mass diffusion, which showed up in the lowest frequency region of less than 100 Hz, increased as the wall density of CNWs increased. It was found that the wall density of CNWs was one of the essential parameters of Pt/CNWs for the electrochemical reaction involving the fluid flow and the mass transfer of active materials.

본 논문은 8가지 방법의 데이터 마이닝 알고리즘(CART, QUEST, CRUISE, 로지스틱 회귀분석, 선형판별분석, 이차판별분석, 신경망분석, 서포트 벡터 머신) 기법과 단일 알고리즘에 2가지 앙상블기법(배깅, 부스팅)을 적용한 16가지 방법을 바탕으로 총 24가지의 방법을 비교하였다. 알고리즘의 성능 비교를 위하여 13개의 이항반응변수로 구성된 데이터를 사용하였다. 비교 기준은 민감도, 특이도 및 오분류율을 사용하여 데이터 마이닝 기법의 성능향상에 대해 평가하였다. 【We studied the performance of 8 data mining algorithms including decision trees, logistic regression, LDA, QDA, Neral network, and SVM and their combinations of 2 ensemble techniques, bagging and boosting. In this study, we utilized 13 data sets with binary responses. Sensitivity, Specificity and missclassificate error were used as criteria for comparison.】

We have developed the bio-electrode measuring the variance of the amount of acetylcholine affected by residual pesticide. The working electrode of the biosensor was made by combination of cobalt phthalocyanine and carbon organic compounds. The biosensors were constructed by screen-printing method. The principle of working electrode is similar to thiocholine sensor. We have fabricated the biosensor using standard screen printing method. Generally, the biosensor made by printing method formed thick film biosensor. When the electrodes were made by electrochemical cells, the generation of current by the addition of enzyme substrate was inhibited by standard solutions of organo-phosphate pesticides. The detection limit of sensor is about 0.5 for carbofuran. We could improve the responsibility of the sensor by controlling the cobalt phthalocyanine and thiocholine concentration ratio. Also we have tested the EPN and Chlorpyrifos pesticides and found that the biosensor is applicable to fast determination of residual pesticides.

In this study, transparent conducting Al-doped zinc oxide (AZO) films with a thickness of 150 nm were prepared on Corning glass substrates by the RF magnetron sputtering with using a ZnO:Al (Al2O3: 2 wt.%) target at room temperature. This study investigated the effects of the post-annealing temperature and the annealing ambient on the structural, electrical and optical properties of the AZO films. The films were annealed at temperatures ranging from 300 to 500 °C in steps of 100 °C by using rapid thermal annealing equipment in oxygen. The thicknesses of the films were observed by field emission scanning electron microscopy (FE-SEM); their grain size was calculated from the X-ray diffraction (XRD) spectra using the Scherrer equation. XRD measurements showed the AZO films to be crystallized with strong (002) orientation as substrate temperature increases over 300 °C. Their electrical properties were investigated by using the Hall measurement and their transmittance was measured by UV–vis spectrometry. The AZO film annealed at the 500 °C in oxygen showed an electrical resistivity of 2.24 × 10− 3 Ω cm and a very high transmittance of 93.5% which were decreased about one order and increased about 9.4%, respectively, compared with as-deposited AZO film.

In this study, transparent and conductive Al-doped zinc oxide (AZO) films were prepared on a glass substrate by an radio frequency (RF) magnetron sputtering method using a 150-nm-thick AZO target (Al: 2 wt.%) at room temperature. We investigated the effects of RF power between 100-350 W (in steps of 50 W) on the structural, electrical, and optical properties of the AZO films. The thickness and cross-sectional images of the films were observed by field emission scanning electron microscopy. The thicknesses of all films were kept constant at 150 nm and grown on a glass substrate. The grain sizes of the AZO films were determined with the X-ray diffraction by using the Scherrer` equation, and their electrical properties were investigated using a Hall effect electronic transport measurement system. The transmittance of the AZO films was also measured by an ultraviolet-visible spectrometer.

A simple method has been developed to suppress the DC term in in-line digital holographic microscope images. The technique is based on the use of the average intensity of a variable number of pixels rather than a fixed number of pixels. The DC-suppression ratio is similar to that associated with the averaging method proposed by Kreis and Juptner, while the image quality resulting from the new method is higher. This method can potentially yield significant improvements in the quality of reconstructed images.

Purpose: To evaluate the clinical and radiological results of arthroscopic tuberoplasty for irreparable massive rotator cuff tears. Materials and Methods: Eleven patients underwent arthroscopic tuberoplasty for irreparable massive rotator cuff tears between December 2004 and April 2007. The mean follow-up period was 17.3 months, and the average age at the time of surgery was 61.7-year-old. Five cases underwent arthroscopic tuberoplasty and 6 cases had arthroscopic subacromial decompression and tuberoplasty, simultaneously. Results: The average Constant score improved from 61.8 to 86.9 and the average UCLA score changed from 14.8 to 31.8 with 6 excellent, 3 good and 2 poor results (p

Three-Dimensional Information and Two-Dimensional Refractive Index Measurements Using a Combined Digital Holographic Microscope Hyungjun Cho, Jingwoong Lim, Doocheol Kim and Younghun Yu Department of Physics, Cheju National University, Jeju 690-756 Sanghoon Shin AP & Tec, Seoul 135-539 Wongun Jang Micro-Optics Team, Korea Optical Photonics Technology Institute, Gwangju 500-460 (Received 12 December 2007, in nal form 10 March 2008) We developed a combined digital holographic microscope that can measure the refractive index of a sample. This system provides highly precise three-dimensional (3-D) information on the sample. We also propose theoretical and experimental methods for the combined holography microscope. The measured data were reasonable although the data error was large. This error was attributable to alignment issues in the experiment. By improving the experimental method, we can measure the refractive index more precisely and obtain more accurate 3-D information on the samples. PACS numbers: 42.40.My, 42.30.W, 42.25.F

In this work, nitrogenated a-C:H (a-C:H:N) films were prepared using the closed-field unbalanced magnetron (CFUBM) sputtering method on Si substrate with graphite target in a Ar + C 2 H 2 + N 2 plasma. We changed the ratio of nitrogen and acethylene gases used as reaction gas and applied the negative DC bias voltage of – 200 V. The tribological properties of a-C:H:N films were observed. In the result, the increase of N 2 as the reaction gas in the plasma showed the growth rate and the N atomic ratio in the films increased markedly. Raman spectroscopy and X-ray photoelectron spectroscopy were used to investigate the chemical bonding structure and sp 3 fraction in the film. As a result, the film had the improvement of the physical properties such as the high hardness of 29 GPa, elastic modulus of 276 GPa and good adhesion of 35 N between a-C:H:N films and substrate. Also, N incorporated a-C:H films exhibited lower friction coefficient than a-C:H film without N. Consequently, the addition of N atoms in the a-C:H film was observed to improve the tribological properties of the film.

The incorporation of N in a-C film is able to improve the friction coefficient and the adhesion to various substrates. In this study, a-C:N films were deposited on Si and steel substrates by closed-field unbalanced magnetron (CFUBM) sputtering system in plasma. The lubricant characteristics was investigated for a-C:N deposited with total working pressure from 4 to 7 mTorr. We obtained high hardness up to 24GPa, friction coefficient lower than 0.1 and the smooth surface of having the extremely low roughness (0.16 nm). The physcial properties of a-C:N thin film are related to the increase of cross-linked bonding clusters in the film. However, the decrease of hardness, elastic modulus and the increase of surface roughness, friction coefficient with the increase of partial pressrue might be due to the effect of energetic ions as a result of the increase of ion bombardment with the increase of ion density in the plasma.

Ti-containing amorphous carbon (a-C:Ti) films shows attractive mechanical properties such as low friction coefficient, good adhesion to various substrate and high wear resistance. The incorporation of titanium in a-C films is able to improve the electrical conductivity, friction coefficient and adhesion to various substrates. In this study, a-C:Ti films were depositied on Si wafer by closed-field unbalanced magnetron (CFUBM) sputtering system composed two targets of carbon and titanium. The tribological properties of a-C:Ti films were investigated with the increase of DC bias voltage from 0 V to - 200 V. The hardness and elastic modulus of films increase with the increase of DC bias voltage and the maximum hardness shows 21 GPa. Also, the coefficient of friction exhibites as low as 0.07 in the ambient. In the result, the a-C:Ti film obtained by CFUBM sputtering method improved the tribological properties with the increase of DC bias volatage.

Organic–inorganic hybrid polymer-like thin films have been deposited on glass and silicon substrates by plasma-enhanced chemical vapor deposition (PECVD) method using single molecular precursors of the organic–inorganic hybrid polymers. Methylcyclohexane and tetraethylorthosilicate (TEOS) were utilized as organic and inorganic precursors, and hydrogen and Ar (argon) were used as bubbler and carrier gases, respectively. In order to compare the difference between the optical, electrical, and mechanical properties of the plasma polymerized thin films, we grew the hybrid polymer-like thin films under the conditions of various radio frequency (RF; using 13.56 MHz) powers in the range of 20–50 W with the annealing temperature of grown thin films in the range 200–5008C. The as-grown polymerized thin films were in first analyzed by FT-IR, C–V, ellipsometry, and nanoindentation. The result of FT-IR showed that the plasma polymerized thin films have highly cross-linked density with increasing RF power and annealing temperature. Impedance analyzer was utilized for the measurements of C–V curves. From the electrical property measurements, the lowest dielectric constant was obtained to be 2.22.

A fundamental problem in digital holography is the presence of zero-order noise in the reconstruction process, which decreases the signal to noise ratio(SNR). For many applications, that reduction of SNR makes digital holography impractical, so a great number of approaches have been tested in order to overcome such a problem. In this paper we use the scanning method to suppress the zero-order diffraction noise and the interference noise between object beams. We demonstrate that it is possible to increase the image quality with the scanning method.

For polymer electrolyte fuel cell applications, carbon nanowalls (CNWs) were synthesized by radical-injection plasma-enhanced chemical vapor deposition, and a high density of Pt nanoparticles (>1012 cm−2) was supported on the CNWs using a supercritical fluid deposition system. The high potential cycle tests were applied and the electrochemical surface area of the Pt nanoparticle-supported CNWs did not change significantly, even after 20 000 high potential cycles. According to transmission electron microscopy observations, the mean diameter of Pt changed slightly after the cycle tests, while the crystallinity of the CNWs evaluated using Raman spectroscopy showed almost no change.

Low-bandgap transparent conductive oxides will be of interest to researchers who wish to address the health hazards of blue radiation emission from electronic displays. Here, we present a single-step, low-temperature fast enough (throughput > 60 nm min−1) process to grow highly c-axis-oriented crystalline Al-doped ZnO thin films via advanced plasma processing. Dual-power DC-magnetron sputtering plasma was employed for the synthesis of thin films. The addition of top power to a pre-existing rectangular power pushed additional ions to a confined plasma and increased the plasma density and electron temperature. The effect of this additional-ion pushing was systematically studied using the microstructure, surface properties, and electronic properties. As a result, bandgap reduction from 3.35 eV to 3.10 eV and tailoring of electrical resistivity (4.89 × 10−4–8.32 × 10−3 Ω cm) and Seebeck coefficients (21–48 µV K−1) were achieved in addition to excellent transparency. Given their properties, the obtained films show promise for multifunctional applications, such as in UV and near-blue radiation shielding, transparent conductive electrodes and low-temperature thermoelectrics.

Study Objective To compare analgesic efficacy of ultrasound (US) guidance alone and US guidance combined with nerve stimulation (NS) for continuous femoral nerve block (CFNB) in patients undergoing total knee arthroplasty (TKA). Design Prospective, randomized double-blind trial. Setting Postanesthesia care unit and general ward. Patients Fifty American Society of Anesthesiologist physical status I to II patients undergoing TKA under spinal anesthesia. Interventions In group A (n = 25), an 18-gauge Tuohy needle was directed at the lower mid-part of the femoral nerve, and a nonstimulating catheter was inserted through the needle under US guidance. In group B (n = 25), an 18-gauge Tuohy needle and stimulating catheter were directed to the lower part of femoral nerve under US guidance, and quadriceps muscle contraction was checked using NS. All patients received a 20-mL loading dose of 0.2% ropivacaine, a continuous infusion of 4 mL/h, and a 4-mL bolus of 0.2% ropivacaine with a lockout time of 60 minutes for patient-controlled analgesia. Measurements The primary outcome was resting and exercising pain quality assessed by numeric rating scale. Other outcomes included procedure time for correct catheter placement, block failure rate, patient satisfaction for postoperative pain control, total dose of local anesthetic, additional opioid requirement, and adverse effects postoperatively. Main Results There were no significant differences between groups in resting and exercising numeric rating scale. Procedure times were longer in group B than group A ( P Conclusions US-guided CFNB was associated with similar analgesic efficacy and block failure rate and reduced procedure time compared to US with NS guidance for CFNB in patients undergoing TKA.

We analyzed the characteristics of gastrointestinal neuroendocrine tumors and examined the outcomes and safety of modalities in rectal neuroendocrine tumors.Between 2007 and 2011, a total of 91 patients with gastrointestinal neuroendocrine tumors were retrospectively reviewed in terms of the characteristics of tumors.Sixty-six patients had rectal neuroendocrine tumors and underwent endoscopic mucosal resection (EMR, n = 29), endoscopic submucosal dissection (ESD, n = 23), or transanal endoscopic microsurgery (TEM, n = 14). The complete resection rate was higher in the ESD group (82.7%) and in the TEM group (100%) compared to the EMR group (65.5%) (P0.046). The complication rate was higher in the ESD group (47.8%) than in the EMR group (18.5%) (P = 0.003). No local tumor recurrence was observed in all patients, regardless of the procedure, during the median follow-up period of 21.5 ± 13.5 months.ESD achieved a higher complete resection rate than EMR and comparable to TEM. Tumor recurrence was not observed in the endoscopic resection and TEM groups, regardless of the completeness of resection. Small neuroendocrine tumors of the gastrointestinal tract can be managed reliably with both endoscopic resection and TEM.

Intramedullary (IM) nailing for humeral shaft fracture has provided excellent outcomes in terms of fracture biology and cosmetic appearance because of the relatively small incision involved. However, antegrade nailing causes issues such as iatrogenic rotator cuff injury. Retrograde nail fixation method could avoid cuff injury, but has shortcomings such as the need for the prone or lateral decubitus position during surgery. We report that the retrograde IM nail fixation technique performed in a supine position and some ancillary techniques for minimizing scars or complications can provide the advantages of both retrograde nailing and supine position during surgery.