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Purpose The improvement of intraoperative parathyroid hormone (IOPTH) assay and localization studies has enabled a minimally invasive parathyroidectomy (MIP) in primary hyperparathyroidism (pHPT). The aim of this study is to analyze the demographics, clinical presentations, and surgical outcomes of the pHPT patients who received surgical management with versus without IOPTH. Methods Analysis of a database was performed on 53 patients who underwent parathyroidectomy for pHPT from 2004 to 2013. Preoperative localization was done by both sestamibi scan and ultrasonography. We divided the patients into two groups (without IOPTH versus with IOPTH) and analyzed the surgical outcomes statistically between two groups. Results The concordance rate of Technetium 99m sestamibi scan and ultrasonography was 73.6% and 90.6%, respectively. The overall cure rate of group 1 (without IOPTH) was 94.9% and that of group 2 (with IOPTH) was 100%. The decline of PTH at postoperative 5 minutes and 10 minutes was 75.2% ± 14.9% and 84.9% ± 8.6% in cured patients. On the other hand, that of noncured patients at 5 minutes and 10 minutes was 17.2% ± 9.7% and 8.2% ± 2.2%. There was a significant difference in the drop rate of IOPTH between cured and persistent patients (P < 0.01). Pathological examination showed adenoma in 41 of 53 patients (77.4%) and hyperplasia in 10 of 53 patients (18.9%). Conclusion Even though the localization studies were successful, IOPTH monitoring is essential to avoid a surgical failure in MIP.

Graphene known for its superb physical properties, such as high transparency and thermal conductivity, is proposed as a solution to the problem of thermal management of the electronic devices, requiring transparency and cooling. It is shown that graphene heat spreader layer drives the heat out of the device more efficiently as compared with the commercially used metal thin films for integrated circuit cooling. An application of graphene heat spreader is proposed and tested in chip-on-film packaging. Graphene performance is compared with a gold layer with a similar transparency experimentally and theoretically as a proof of the efficient thermal management capability of graphene.

Purpose The incidence of papillary thyroid carcinoma (PTC) arising from the isthmus is low; however, these tumors have aggressive clinical and pathological features. Moreover, the existing guidelines regarding the extent of surgery for this type of tumor are unclear. Methods This study enrolled 282 patients who underwent total thyroidectomy with bilateral central lymph node dissection. The patients were divided into 2 groups based on the location of the median line of the PTC. Group I included patients in whom the median line was located between the lateral margins of the trachea; group II included all others. We compared the 2 groups and conducted a multivariate analysis to assess risk factors for contralateral node metastasis from a PTC arising from the isthmus. Results Patients in group I had significantly higher frequencies of extrathyroidal extension and central lymph node metastasis. Group I also had a higher frequency of contralateral node metastasis, and a tumor size >1.0 cm was identified as an independent risk factor for contralateral node metastasis among patients in this group. Conclusion Bilateral central lymph node dissection could be considered for patients with isthmic PTCs >1.0 cm in size who have clinically suspicious node metastasis.

Summary Background Preservation of the external branch of the superior laryngeal nerve (EBSLN) during thyroidectomy is important because its injury may lead to frequent occurrence of vocal fatigue and the inability to perform superenergetic phonation. Most studies on the anatomy of EBSLN have been performed in Western countries and, thus, have some limitations in their application to Koreans. We explored the anatomy of EBSLNs using intraoperative neuromonitoring (IONM) in Korean adults. Methods Between August 2011 and December 2011, 50 patients underwent thyroidectomy at Korea University, Anam Hospital in Seoul, Korea. IONM was performed with the NIM response 3.0 system. Results Forty-two total thyroidectomies and eight lobectomies were performed with IONM and 92 EBSLNs were evaluated. Type I EBSLN was observed in 15 of the 92 nerves (16.3%), type IIa EBSLN was noted in 52 (56.5%) and type IIb EBSLN was noted in 25 (27.2%). Patients with types IIa and IIb were at higher risk of injuries and these types were more frequently observed (83.7%) compared with previous Western studies. We found that 35.9% of distal insertion sites of EBSLNs were located within 1 cm of the center of the cricoid cartilage. Conclusion Surgeons should pay close attention to preserving the EBSLN during thyroidectomy in Korean patients because their EBSLNs are more frequently located beneath the superior thyroid vessels.

Background The aim of the present study was to compare the surgical outcomes of robotic thyroidectomy using the bilateral axillo-breast approach (BABA) with open conventional thyroidectomy. Methods Database of patients who underwent thyroidectomy with cervical lymph node dissection after diagnosed as papillary thyroid carcinoma between July 2008 and February 2013 were examined. Clinicopathologic characteristics, surgical outcomes, and postoperative morbidities of robot group and open group were investigated. Results The dominant tumor size (P = 0.974), body mass index (BMI) (P = 0.426), and the mean number of metastatic lymph nodes in central compartment neck dissection (P = 0.269) were comparable between the two groups. The mean number of retrieved central lymph nodes was higher in the open group than in the robot group (P = 0.001). Postoperative complications were comparable: hypoparathyroidism in 2 weeks (P = 0.296) and 3 months (P = 0.446) after the surgery; vocal cord palsy in 2 weeks (P = 0.363) and 3 months (P = 0.312); hematoma (P = 0.162); and wound infection (P = 0.421). Conclusions Robotic thyroidectomy using BABA may be a technically feasible and safe procedure comparable to conventional open surgery especially in node-negative patients. J. Surg. Oncol. 2015 111:141–145. © 2014 Wiley Periodicals, Inc.

Functional van der Waals heterojunctions of transition metal dichalcogenides are emerging as a potential candidate for the basis of next-generation logic devices and optoelectronics. However, the complexity of synthesis processes so far has delayed the successful integration of the heterostructure device array within a large scale, which is necessary for practical applications. Here, a direct synthesis method is introduced to fabricate an array of self-assembled WSe2 /MoS2 heterostructures through facile solution-based directional precipitation. By manipulating the internal convection flow (i.e., Marangoni flow) of the solution, the WSe2 wires are selectively stacked over the MoS2 wires at a specific angle, which enables the formation of parallel- and cross-aligned heterostructures. The realized WSe2 /MoS2 -based p-n heterojunction shows not only high rectification (ideality factor: 1.18) but also promising optoelectrical properties with a high responsivity of 5.39 A W-1 and response speed of 16 µs. As a feasible application, a WSe2 /MoS2 -based photodiode array (10 × 10) is demonstrated, which proves that the photosensing system can detect the position and intensity of an external light source. The solution-based growth of hierarchical structures with various alignments could offer a method for the further development of large-area electronic and optoelectronic applications.

Despite many encouraging properties of transition metal dichalcogenides (TMDs), a central challenge in the realm of industrial applications based on TMD materials is to connect the large-scale synthesis and reproducible production of highly crystalline TMD materials. Here, the primary aim is to resolve simultaneously the two inversely related issues through the synthesis of MoS2(1-x) Se2x ternary alloys with customizable bichalcogen atomic (S and Se) ratio via atomic-level substitution combined with a solution-based large-area compatible approach. The relative concentration of bichalcogen atoms in the 2D alloy can be effectively modulated by altering the selenization temperature, resulting in 4 in. scale production of MoS1.62 Se0.38 , MoS1.37 Se0.63 , MoS1.15 Se0.85 , and MoS0.46 Se1.54 alloys, as well as MoS2 and MoSe2 . Comprehensive spectroscopic evaluations for vertical and lateral homogeneity in terms of heteroatom distribution in the large-scale 2D TMD alloys are implemented. Se-stimulated strain effects and a detailed mechanism for the Se substitution in the MoS2 crystal are further explored. Finally, the capability of the 2D alloy for industrial application in nanophotonic devices and hydrogen evolution reaction (HER) catalysts is validated. Substantial enhancements in the optoelectronic and HER performances of the 2D ternary alloy compared with those of its binary counterparts, including pure-phase MoS2 and MoSe2 , are unambiguously achieved.

Background Although several recent studies have demonstrated the feasibility and safety of robotic adrenalectomy, it is unknown whether this procedure has advantages over the traditional laparoscopic approach. This study compared our initial experience using the da Vinci-S® robotic surgical system during laparoscopic adrenalectomy with our experience with traditional laparoscopic adrenalectomy. Methods From October 2009 to May 2012, 23 consecutive patients (13 women, 10 men) underwent laparoscopic adrenalectomy by the same surgeon at Anam Hospital, Korea University Medical Center. Fifteen patients (9 women, 6 men) underwent robot-assisted adrenalectomy (right-sided, 4 patients; left-sided, 11 patients). Eight patients (4 women, 4 men) underwent traditional laparoscopic adrenalectomy (right-sided, 5 patients; left-sided, 3 patients). The lateral transperitoneal approach was used for all patients. Results There were no cases of conversion to traditional laparoscopic or open surgery. The mean operative time was longer in the robotic group (208.2 minutes, range 120–320) than the laparoscopic group (181.13 minutes, range 75–270). There were no cases of intraoperative complications or mortality. The mean hospital stay did not differ significantly between groups (robotic group, 5.86 days (SD 1.16); laparoscopic group, 6.71 days (SD 1.38)). Conclusions With its magnified stereoscopic three-dimensional vision, elimination of tremor, and ability to articulate and rotate surgical instruments, the da Vinci-S® robotic system may be an ideal surgical tool for the operation of adrenal lesions. Robotic adrenalectomy appears to be a safe and effective alternative to traditional laparoscopic adrenalectomy. Copyright © 2013 John Wiley & Sons, Ltd.

Objective The aim of this study was to determine the protein expression and prognostic value of epidermal growth factor receptor (EGFR), p53 and galectin-3 in papillary thyroid carcinoma (PTC). Methods A retrospective analysis was performed using tumour specimens from patients with PTC who underwent thyroidectomy between July 2007 and December 2008. The percentages of tumour cells staining positively for EGFR, galectin-3 and p53 were determined by immunohistochemistry. Associations between protein expression and age, sex, extrathyroidal extension and lymph node metastasis were assessed, together with the total Metastasis, Age, Completeness of resection, Invasion, Size (MACIS) score (a marker of prognosis). MACIS prognostic scores were categorized into four groups. Results Data from 168 patients with PTC (mean follow-up, 35 months) were included. EGFR expression was significantly associated with male sex and lymph node metastasis; p53 expression was higher in males than in females; galectin-3 expression was not significantly associated with age, sex, extrathyroidal extension, lymph node metastasis or total MACIS score category, however. Conclusion Immunohistochemical evaluation of EGFR and p53 expression in patients with PTC may be useful for determining prognosis, in PTC patients.

목적 : 유방의 유두상 병변은 양성 종양의 10%미만이며, 모든 악성종양의 0.5~0.2%를 차지한다. 중심부바늘생검에서 유방의 유두종양으로 진단된 경우 외과적 절제의 필요성에 있어서는 현재까지 논란이 있다. 이에 중심부바늘생검 결과 유두종양으로 진단되고 절제생검을 시행한 환자에서 유방암의 예측인자를 연구하였다. 대상과 방법 : 2009년 6월부터 2012년 6월까지 고려대학교 구로병원 외과에서 초음파유도하 중심부바늘생검 결과 유두종양과 비정형 유두종으로 진단되고 절제생검을 시행한 97예를 대상으로 하였다. 수술 전 중심부바늘생검과 수술 후 조직병리 소견에서 종양의 특성 및 크기를 분석하였다. 결과 : 97에 모두 여성이었으며 평균 연령은 45.1(16~68)세였다. 최종 조직검사결과 유두종양과 악성종양 환자의 평균 연령의 차이는 없었다. 중심부바늘생검에서 유두종양이였던 71예 중 절제생검의 최종조직검사 결과는 64(90.1%)예는 유두종양, 7(9.9%)예, 4(22.2%)예 및 7(38.9%)예로 유의한 차이가 있었다(P=0.001). 증상에서는 중심부바늘생검에서 유두종양인 경우에는 촉지성 종괴에서 유의하게 악성 종양이 많았다(P=0.03). 초음파 측정 종양의 크기가 1.5cm이상일 때 유의하게 악성 종양이 많았다(P=0.005). 중심부 바늘생검에서 유두종인 경우는 최종조직검사 결과 양성과 악성종양에서 초음파 측정 종양의 크기에서는 유의한 차이가 없었으나, 절제 후 최종조직 검사에서는 유의한 크기의 차이가 있었다(P=0.19, 0.002). 중심부바늘생검에서 비정형 유두종양인 경우에서는 초음파 측정 종양의 크기와 최종조직 크기에서 모두 유의한 차이가 있었다. (P=0.003, 0.019). 중심부바늘생검에서 유두종양인 경우 BIRAD 분류에 의한 분석결과 유의한 차이가 보였으나 (P=0.023), 비정형 유두종양에서는 유의한 차이가 없었다. 다변량 분석에서는 초음파 측정 종양크기가 1.5cm 을 초과한 경우에서만 유의한 결과를 보였으며 (P=0.45, OR=2.4 95% CI 0.16-0.95). 결론 : 중심부바늘생검 결과 비정형 유두종양의 절제생검의 필요성을 본 연구에서 다시 한번 확인할 수 있었다. 중심부바늘생검에서 조직병리 결과가 유두종양이라도 1.5cm이상이거나 촉지성 병변이거나, 영상의학적 소견과 중심부바늘생검의 결과에 불일치가 있는 경우에는 외과적 절제생검이 필요하다고 생각된다.

Background. It has long been recognized that some human breast cancers are hormone dependent. Preeclampsia is a syndrome of pregnancy defi ned by the onset of hypertension and proteinuria and characterized by dysfunction of the maternal endothelium. Many hormonal changes occur with preeclampsia, and we hypothesize that these changes may infl uence the risk of maternal breast cancer. We also analyzed the relation between pregnancy-induced hypertension (PIH) and maternal risk of breast cancer. Methods. Among 13 relevant publications about preeclampsia and six relevant publications about PIH, some studies fi nd preeclampsia associated with a lower risk of breast cancer, but others did not. Therefore, these results are inconclusive. We conducted meta-analysis to evaluate more precisely the relationship between preeclampsia, PIH and maternal risk of breast cancer. Results. The pooled estimate of the hazard ratio (HR) associated with preeclampsia was 0.86 (95% CI 0.73 ‐ 1.01), and that associated with PIH was 0.83 (0.66 ‐ 1.06), both based on the random effects model. Conclusion. Some suggestive but not entirely consistent nor conclusive evidence was found on the association between the history of preeclampsia or PIH with the subsequent risk of breast cancer.

Purpose: The lymph node ratio (LNR) is an important prognostic factor in papillary thyroid carcinoma (PTC), but micrometastases in cervical lymph nodes (LNs) are not of great clinical importance. In this study, we analyzed the accuracy of prediction of the prognosis depending on whether micrometastases were included in the number of metastatic LNs when calculating LNR. Methods: The study included 353 PTC patients who underwent total thyroidectomy with neck LN dissection, and calculated LNR by 2 methods according to whether micrometastases were included in the number of metastatic LNs: Method 1 did not and method 2 did include. To compare the predictive values of LNR by the 2 methods, correlation coefficients and receiver operating characteristic (ROC) curves were analyzed. Results: Positive correlations were found between LNR and preablation stimulated thyroglobulin (sTg) levels in both methods, but the correlation between method 1 LNR and preablation sTg level was significantly stronger than that for method 2 (Fisher z = 1.7, P = 0.045). The areas under these 2 independent ROC curves were analyzed; the prognostic efficacy of method 1 LNR was more accurate than that of method 2 LNR, and the difference was statistically significant (P = 0.0001). Conclusion: Regional recurrence of PTC can be predicted more accurately by not including micrometastases in the number of metastatic LNs when calculating LNR.

Inherent defects, such as grain boundaries (GBs), wrinkles and structural cracks, present on chemical vapor deposition (CVD)-grown graphene are inevitable because of the mechanism used for its synthesis. Because graphene defects are detrimental to electrical transport properties and degrade the performance of graphene-based devices, a defect-healing process is required. We report a simple and effective approach for enhancing the electrical properties of graphene by selective graphene-defect decoration with Pd nanoparticles (Pd NPs) using a wet-chemistry-based galvanic displacement reaction. According to the selective nucleation and growth behaviors of Pd NPs on graphene, several types of defects, such as GBs, wrinkles, graphene regions on Cu fatigue cracks and external edges of multiple graphene layers, were precisely confirmed via spherical aberration correction scanning transmission electron microscopy, field-emission scanning electron microscopy and atomic force microscopy imaging. The resultant Pd-NP-decorated graphene films showed improved sheet resistance. A transparent heater was fabricated using Pd-decorated graphene films and exhibited better heating performance than a heater fabricated using pristine graphene. This simple and novel approach promises the selective decoration of defects in CVD-grown graphene and further exploits the visualization of diverse defects on a graphene surface, which can be a versatile method for improving the properties of graphene. Decorating defects with palladium nanoparticles enhances the electrical properties of chemical vapour deposited graphene. Unlike other methods of synthesizing graphene, chemical vapour deposition can produce large areas of the two-dimensional material, but it also tends to create defects. Han-Bo-Ram Lee from Incheon National University and Taeyoon Lee from Yonsei University in South Korea, together with colleagues across the country, have shown that palladium nanoparticles automatically attach themselves to imperfections in chemical vapour deposited graphene, thereby improving its electrical properties. They chemical vapour deposited graphene on copper and dipped it in a palladium chloride solution. The greater chemical reactivity of defect sites in graphene causes palladium atoms to selectively attach to imperfections such as wrinkles, cracks and grain boundaries, creating nanoparticles at these sites. The researchers anticipate that the method could be used in the manufacture of smart mirrors and displays. Selective decoration of palladium nanoparticles on diverse graphene-defect sites. Graphene grown by chemical vapor deposition method has structural imperfections, such as grain boundaries, wrinkles and topological cracks, which cause reduced graphene-based device performance. Herein, we selectively decorated graphene defects with metal nanoparticles (Pd and Ag) by using a wet-chemistry-based galvanic displacement reaction within a few minutes without generating damage on graphene. The defect-decorated graphene showed a noticeable improvement in electrical characteristics, and defect-decorated graphene-based transparent heater showed better heating performance than a heater fabricated using pristine graphene.

We demonstrate infrared photodetectors based on graphene-Bi 2 Se 3 heterostructures with high responsivity (≥1.9 A/W) at room temperature. Strong photogating effect across the tunneling barrier and built-in potential enables the internal quantum efficiency larger than 100 %.

Mothers` labor market participation has increased significantly in Korea. This article explores how working mothers in Korea with children under the age of six allocate their time in order to spend time with children, and what substitutes they rely on when they are unable to provide childcare. Mothers who participate in the labor market have begun to narrow the gap in child-care time between themselves and mothers who are full-time homemakers; they often compensate for insufficient care time during the week by increasing care time on weekends and increasing the quality of time spent with their children. Substitute caregivers include grandparents and, to a much lesser extent, fathers, but the burden of childcare has not been effectively shared within the family, and working mothers continue to face significant time pressure.

The effects of maleic anhydride-grafted styrene-ethylene-butylene-styrene copolymer (SEBS-g-MAH) on the mechanical and morphological properties of polypropylene (PP) and poly(acrylonitrile-butadiene-styrene) (ABS) blends were investigated. Based on mechanical properties, including impact and tensile strengths, the PP/ABS (70/30) blends containing SEBS-g-MAH showed improved impact strength with minimal loss of tensile strength. As determined from morphological studies of the PP/ABS blends, addition of SEBS-g-MAH decreased PP/ABS blend droplet size more than the addition of SEBS. Additionally, the effects of SEBS-g-MAH and SEBS on the mechanical and morphological properties of the PP/ABS (70/30) blends were investigated during accelerated aging in an oven at 90°C for 72 h (one cycle). The impact strength of the PP/ABS (70/30) blends with SEBS-g-MAH (7 phr) decreased less than 10% after five cycles, but blends with SEBS (7 phr) and blends without compatibilizer decreased as much as 37%. The tensile strengths of the PP/ABS (70/30) blends after accelerated aging indicated a trend similar to that of the impact strength. The morphological studies indicated no significant changes in the PP/ABS (70/30) blends with SEBS-g-MAH; however, many cavities and damages were observed in the blend with SEBS. The above results suggest that SEBS-g-MAH acts as an impact modifier and as a good compatibilizer in the PP/ABS (70/30) blends. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Women who undergo a greater number of menstrual cycles may be at increased risk of breast cancer, possibly due to cumulative exposure to ovarian hormones. Pregnancy reduces the lifetime number of menstrual cycles and also influences the levels of ovarian hormones. Twin pregnancies differ from singleton pregnancies in both hormone levels and perinatal changes. To date, a meta-analysis on the effects of twin birth on the risk of maternal breast cancer has not been conducted. Among 17 relevant publications identified in a systematic search, some suggest that twin births may be associated with lower breast cancer risk but others do not; therefore, the results are inconclusive. Although our pooled results of all 17 published studies did not show a reduced maternal risk of breast cancer for twin births (HR 0.94; 95% CI = 0.87-1.02; P = 0.127), a trend toward reduced maternal risk of breast cancer was identified in a subgroup analysis of cohort studies (HR 0.91; 95% CI = 0.83-1.01; P = 0.068). The results of this meta-analysis suggest that twin pregnancy does not significantly decrease the maternal risk of breast cancer.

This paper presents the design of a wideband spiral antenna for ingestible capsule endoscope systems and a comparison between the experimental results in a human phantom and a pig under general anesthesia. As wireless capsule endoscope systems transmit real-time internal biological image data at a high resolution to external receivers and because they operate in the human body, a small wideband antenna is required. To incorporate these properties, a thick-arm spiral structure is applied to the designed antenna. To make practical and efficient use of antennas inside the human body, which is composed of a high dielectric and lossy material, the resonance characteristics and radiation patterns were evaluated through a measurement setup using a liquid human phantom. The total height of the designed antenna is 5 mm and the diameter is 10 mm. The fractional bandwidth of the fabricated antenna is about 21% with a voltage standing-wave ratio of less than 2, and it has an isotropic radiation pattern. These characteristics are suitable for wideband capsule endoscope systems. Moreover, the received power level was measured using the proposed antenna, a circular polarized receiver antenna, and a pig under general anesthesia. Finally, endoscopic capsule images in the stomach and large intestine were captured using an on-off keying transceiver system.

Mechanical, morphological and rheological properties of polycarbonate (PC) and poly (lactic acid) (PLA) blends with compatibilizers have been investigated. Three types of compatibilizers were used: poly(styrene-g-acrylonitrile)-maleic anhydride (SAN-g-MAH), poly(ethylene-co-octene) rubber-maleic anhydride (EOR-MAH) and poly(ethylene-co-glycidyl methacrylate) (EGMA). The maximum value of the mechanical properties such as impact and tensile strengths of the PC/PLA (70/30, wt%) blend before or after hydrolysis was observed when the SAN-g-MAH was used as a compatibilizer at the amount of 5 phr. From the interfacial tension between PC and PLA which was determined from the weighted relaxation spectra using Palierne emulsion model, minimum value of interfacial tension (0.08 mN/m) was observed when the SAN-g-MAH (5 phr) was used. From the morphological studies of the PC/PLA (70/30) blends, the PLA droplet size showed minimum (0.19 μm) at the 5.0 phr SAN-g-MAH. From the results of mechanical, morphological and rheological properties of the PC/PLA (70/30) blend, it is suggested that the SAN-g-MAH is the most effective compatibilizer to improve the mechanical strength of the PC/PLA (70/30) blends among the compatibilizers used in this study, especially at the amount of 5 phr.

In this article, a new antenna is introduced for ingestible capsule endoscope systems. As capsule endoscope systems are supposed to operate in the human body and they transmit internal image data with high resolution to external receivers, a wideband small antenna is required. To obtain these properties, the proposed antenna is designed in the form of thick-arm spiral structure. The total height of the antenna is 5 mm and the diameter is 10 mm. The fractional bandwidth of the proposed antenna is 21% with VSWR < 2, which is wide enough for WBAN in body communication and it has the isotropic radiation pattern. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:529–532, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25808

The WRF-based real-time forecast system ( http://jhwc.snu.ac.kr/weather ) of the Joint Center for High-impact Weather and Climate Research (JHWC) has been in operation since November 2006; this system has three nested model domains using GFS (Global Forecast System) data for its initial and boundary conditions. In this study, we evaluate the improvement in daily and hourly weather prediction, particularly the prediction of summer rainfall over the Korean Peninsula, in the JHWC WRF (Weather Research and Forecasting) model system by 3DVAR (three-Dimensional Variational) data assimilation using the data obtained from KEOP (Korea Enhanced Observation Program). KEOP was conducted during the period June 15 to July 15, 2007, and the data obtained included GTS (Global Telecommunication System) upper-air sounding, AWS (Automatic Weather System), wind profiler, and radar observation data. Rainfall prediction and its characteristics should be verified by using the precipitation observation and the difference field of each experiment. High-resolution (3 km in domain 3) summer rainfall prediction over the Korean peninsula is substantially influenced by improved synoptic-scale prediction in domains 1 (27 km) and 2 (9 km), in particular by data assimilation using the sounding and wind profiler data. The rainfall prediction in domain 3 was further improved by radar and AWS data assimilation in domain 3. The equitable threat score and bias score of the rainfall predicted in domain 3 indicated improvement for the threshold values of 0.1, 1, and 2.5 mm with data assimilation. For cases of occurrence of heavy rainfall (7 days), the equitable threat score and bias score improved considerably at all threshold values as compared to the entire period of KEOP. Radar and AWS data assimilation improved the temporal and spatial distributions of diurnal rainfall over southern Korea, and AWS data assimilation increased the predicted rainfall amount by approximately 0.3 mm 3hr−1.

Although various new agents have been developed for the treatment of patients with metastatic breast cancer (MBC), overall survival rates have changed little in the last half century. We conducted meta-analysis to verify the clinical efficacy of bevacizumab for the salvage treatment of MBC. Event-based hazard ratios (HR) with 95% confidence intervals (95% CIs) were derived, and a test of heterogeneity was applied. Four studies, with a total of 2,860 patients, met the inclusion criteria for analysis. The pooled results of clinical efficacies were: HR for progression free survival 0.69 (95% CI, 0.58–0.81, z = 4.54, P

In breast cancer, the expression pattern of CXCR4 may be correlated with the degree of axillary lymph node involvement. The aim of this study was to evaluate the contributing factors that contribute to the correlation between CXCR4 expression and axillary lymph node metastasis in breast cancer.Between August 1997 and August 2002, sections of paraffin-embedded tissue were obtained from 107 patients who received optimal treatment for breast cancer. The expression of CXCR4 was evaluated by immunohistochemical staining.A significant correlation was found in the expression of nuclear CXCR4 and lymph node metastasis (P = 0.03). We found a significant correlation between a high nuclear expression of CXCR4 and axillary lymphatic metastasis in estrogen and progesterone receptor negative breast cancer (P = 0.01 and P = 0.01). There was a significant correlation between the high expression of nuclear CXCR4 and axillary lymphatic metastasis in comparisons between positive estrogen and/or progesterone receptor expression and negative expression (P = 0.02).Our results showed that high expression of nuclear CXCR4 was significantly correlated with lymph node metastasis in breast cancer. The high expression of nuclear CXCR4 in hormone receptor negative breast cancer was associated with a high possibility of lymph node metastasis.

Background: The cervical lymph node metastasis (CLNM) of papillary thyroid microcarcinoma (PTMC) is not uncommon. However, prophylactic cervical lymph node dissection in all PTMC is debatable. Molecular markers of predicting CLNM would help to decide to either do or not do cervical lymph node dissection which might increase morbidities. Aims: We aimed to characterize gene expression profiles and molecular markers of CLNM in PTMC. Settings and Design: The thyroid frozen tissues were obtained with from six PTMC patients, who underwent total thyroidectomy. Methods: We performed oligonucleotide microarray analysis with three PTMCs with CLNM and three without CLNM. Real-time quantitative reverse transcription-polymerase chain reaction was used to validate the gene. Statistical Analysis Used: We used linear models for microarray data. Results: We identified 12 differentially expressed gene, and most one is endoplasmic reticulum aminopeptidase 2 (ERAP2). Conclusion: ERAP2 might be associated with CLNM in PTMC.

The purpose of this study was to identify predictors of difficult robotic thyroidectomy using the bilateral axillo-breast approach (BABA) for the management of patients with papillary thyroid carcinoma (PTC).We examined a database containing details of patients with PTC who had undergone robotic thyroidectomy with cervical lymph node dissection between July 2008 and June 2013. Patients were subgrouped into difficult thyroidectomy and non-difficult thyroidectomy to identify predictors associated with difficult thyroidectomy corresponding to the time of operation. Clinicopathologic characteristics, surgical outcomes, and postoperative morbidities were investigated.Male sex was the only significantly different clinicopathologic factor between the 2 groups (p = .013). Other factors, such as age (p = .809) and body mass index (BMI; p = .202), were comparable between the 2 groups. The rates of postoperative complications, such as hypoparathyroidism, vocal cord palsy, and seroma, in the difficult thyroidectomy group were not significantly different from those in the non-difficult thyroidectomy group. There was no hematoma or wound infection. Male sex was the only independent factor associated with difficult thyroidectomy (odds ratio [OR] = 5.379; 95% confidence interval [CI] = 1.052-27.502; p = .043), according to the multivariate logistic regression model.Male sex was the only predictive factor for difficult robotic thyroidectomy using BABA. Further evaluations should be performed to ascertain additional factors associated with difficult robotic thyroidectomy. © 2015 Wiley Periodicals, Inc. Head Neck 38: E954-E960, 2016.

Recurrent laryngeal nerve (RLN) palsy is the most common and serious complication of thyroid surgery. The use of energy-based devices (EBDs) has replaced hand-tying methods in many institutions. However, EBD use proximal to the RLN presents risks related to lateral thermal spread and associated nerve damage. THUNDERBEAT (TB) is one of the most widely used EBDs. This study aimed to test the safety of TB during thyroidectomy.Four piglets weighing 30-40 kg experienced thyroidectomy while continuous electrophysiologic monitoring (continuous intraoperative neuromonitoring) occurred, using an electromyography endotracheal tube and NIM 3.0 response system. TB was applied at various distances from the RLN, and we assessed the safety of the protocols.Adverse electromyography events did not occur at distances3 mm from the RLN. Amplitude decreased at 2 mm from the RLN after 8 s. However, immediate loss of signal occurred at 1 mm from the RLN, likely due to immediate shrinkage of surrounding tissue after TB application.TB can be used safely at 3 mm from the RLN but must be used for8 s at more proximal locations. This is the first report assessing the safety of TB, and findings indicate that TB should be used at least 1 mm from the RLN to avoid injury.

Modified TiO 2 suspensions were prepared by adding silver nitrate to the suspension such that the desired Ag/Ti atomic concentration ratio was obtained. Ag-deposited TiO 2 particles were formed by a chemical reduction method using a semi-batch reactor and were characterized. The photocatalytic disinfection of E. coli using the nanoparticles was also investigated.

2.22‐inch qVGA (240×320) amorphous silicon thin film transistor liquid active matrix crystal display (a‐Si TFT‐AMLCD) panel has been successfully demonstrated employing a 2.5 um fine‐patterning technology by a wet etch process. Higher resolution 2.22‐inch qVGA LCD panel with an aperture ratio of 58% can be fabricated as the 2.5 um fine pattern formation technique is integrated with high thermal photo‐resist (PR) development. In addition, a novel concept of unique a‐Si TFT process architecture, which is advantageous in terms of reliability, was proposed in the fabrication of 2.22‐inch qVGA LCD panel. Overall results show that the 2.5 um fine‐patterning is a considerably significant technology to obtain higher aperture ratio for higher resolution a‐Si TFT‐LCD panel realization.

The purpose of this study was to evaluate the relationship between intimal hyperplasia and transforming growth factor-beta1 (TGF-beta1) mRNA expression in synthetic arterial grafts and also to clarify the effect of angiotensin-converting enzyme inhibitor (ACEI) on perianastomotic intimal hyperplasia and TGF-beta1 mRNA expression. Thirty New Zealand White rabbits were randomly divided into two groups (15 each); one group was administered Captopril 10 mg/kg/day per os as an ACE inhibitor, and the other group received on saline as a vehicle from 7 days prior to operation until the graft was harvest (1, 8, or 14 weeks). A 10-mm segment of an expanded polytetrafluoroethylene graft (3 mm in diameter) was implanted in the right common carotid artery of the rabbits; 15 rabbits had by-pass grafting alone (Graft Alone group) and the other 15 rabbits had by-pass graft along with the ACEI (Graft plus ACEI group). The artery grafts were harvested. The intima to media height ratio (IMHR) and the TGF-beta1 mRNA expression level in perianastomotic graft tissue by reverse transcription-polymerase chain reaction (RT-PCR). The IMHRs gradually increased from 1 to 14 weeks in both groups (vs. 1 wk in each group, p

Crystallization behavior of amorphous silicon (a-Si) using the field aided lateral crystallization (FALC) process was investigated. The lateral crystallization of a-Si was remarkably enhanced at the negative electrode side with the aid of an electric field, while it was retarded at the positive electrode side. FALC velocity using Ni was as high as 11 μm/h at 500 °C with an electric field of 4 V/cm. In addition, the nickel silicide phase, known to be a mediator for low temperature crystallization, can be driven from either the drain to source or source to drain in the active layer, depending on the bias conditions during crystallization. Thus, the defects originating from residual nickel silicide can be driven out from the channel region. Due to such an asymmetric location of the residual nickel silicide, the leakage current of the polycrystalline silicon thin film transistor (poly-Si TFT) using the FALC process showed a leakage current of approximately one order of magnitude lower when we reversed the probing polarity. Therefore, it was judged that the judicious selection of the bias condition during the FALC process can be useful in improving the electrical properties of poly-Si TFT.

Background and Aims: Extrathyroidal extension (ETE) is one of the most important factors correlated to poor outcome of papillary thyroid carcinoma (PTC). However, the role of ETE in the prognosis of papillary thyroid microcarcinoma (PTMC) and the factor associated with ETE of PTMC are unclear. We investigated clinicopathological, immunohistochemical factors associated with ETE of PTMC to identify whether PTMC with ETE would have more adverse prognostic factors and higher risk for recurrence. Setting and Design: We enrolled patients performed thyroidectomy due to PTC between January 2003 and June 2008 and selected patients diagnosed with PTMC among them. We investigated numerous clinicopathological, immunohistochemical factors of selected patients. Materials and Methods: Data from 325 patients diagnosed with conventional PTMC by intraoperative frozen section and final pathology were recorded retrospectively. Statistical Analysis Used: A χ2 test or an independent two-sample t-test, multiple logistic regression analysis, the Kaplan-Meier method, and log-rank test. Results: Thirty-four percent of patients (325 of 952) had PTMC on final pathology. Among them, the number of patients with and without ETE was 91 and 234, respectively. On both univariate and multivariate analysis; ETE of PTMC correlated with size (P < 0.001); tumor, node, and metastasis (TNM) staging (P = 0.001); multifocality (P = 0.001); lymph node metastasis (P < 0.001); radioactive iodine (RAI) therapy (P = 0.001); and recurrence (P = 0.037). Conclusions: ETE of conventional PTMC is associated with size, multifocality, lymph node metastasis, and recurrence. More extensive surgery should be considered for patients having ETE identified by intraoperative frozen sections, preoperative imaging, and intraoperative finding and other high risk factors.

Endoscopic thyroid surgery is gaining wide acceptance; however, existing endoscopic methods for thyroidectomy have shown several limitations. Recently, a transoral technique using video assistance and endoscopy has been reported for thyroidectomy. The aim of this study was to define a new technique of transoral thyroidectomy using a mandibular periosteal approach to complement other types of natural orifice surgery and minimally invasive surgery.Transoral periosteal thyroidectomies were performed in seven living pigs to evaluate the feasibility and safety of the new approach. Total thyroidectomies were performed in all animals. Follow-up examinations were carried out for 7 days and followed by autopsy.Through three trocars in the mandibular periosteal area, it was possible to create a working space under the platysma muscle and to reach the pretracheal area. Total thyroidectomies were also performed via the transoral, mandibular periosteal approach without complications in seven orally intubated living pigs. Postoperatively, the white blood cell count remained normal in all cases. On the postoperative sacrifice of the pigs, three locally encapsulated seromas were observed. Both recurrent laryngeal nerves were intact in all cases.Transoral periosteal thyroidectomy could be feasible and safe.

The use of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) in electrodes and electrical circuits presents a number of challenges that are yet to be overcome, foremost amongst which are its relatively low conductivity, low coatability on hydrophobic substrates, and decreased conductivity at large strains. With this in mind, this study suggests a simple way to simultaneously address all of these issues through the addition of a small amount of a nonionic surfactant (Triton X-100) to commercial PEDOT:PSS solutions. This surfactant is shown to considerably reduce the surface tension of the PEDOT:PSS solution, thus permitting conformal coatings of PEDOT:PSS thin film on a diverse range of hydrophobic substrates. Furthermore, this surfactant induces the formation of PEDOT nanofibrils during coating, which led to the high conductivity values and mechanical stability at large strains (e=10.3%). Taking advantage of the superior characteristics of these PEDOT:PSS thin films, a highly flexible polymer solar cell was fabricated. The power conversion efficiency of this solar cell (3.14% at zero strain) was preserved at large strains (e=7.0%).

The direct observation of the domain size and defect distribution in a graphene film is important for the development of electronic applications involving graphene. Here we report a promising method for observing graphene domains grown by chemical vapour deposition. The unavoidable development of crack or pinhole defects during the growth and transfer processes is visualized using a liquid crystal layer. Liquid crystal molecules align anisotropically with respect to the graphene domains and exhibit distinct birefringence properties that can be used to image the graphene domains. This approach is useful for visualizing the crack distributions and their generation process in graphene films under external strain. This type of simple observation method provides an effective route to evaluating the quality and reliability of graphene sheets for use in various electronic devices.

We report a case of adrenocortical tumor that coexisted with paragangliomas. A 35-year-old woman was admitted to the hospital because of left upper abdominal pain. A palm-sized mass was palpated at left upper quadrant. Hormonal studies revealed the features of pheochromocytoma. An emergency operation was performed because hemorrhage of the tumor was suspected. A 10 cm diameter ruptured mass was found in the left adrenal area and other tumors were also noted adjacent to inferior vena cava (IVC). The pathologic report revealed that the adrenal mass was an adrenocortical tumor with hemorrhagic necrosis and that the tumors adjacent to IVC were paragangliomas. This was the first case of adrenocortical tumor with paragangliomas in our Medline search result, hence we report the case with a review of the literature.

Reovirus isolates from human, striped-field mouse (Apodemus agrarius) and Korean field mouse (A. peninsulae) in Korea showed extensive variability in the patterns of electrophoretic migration of the double-stranded RNA (dsRNA) genome segments. Hemagglutination inhibition (HI) test was performed for serotype determination of 12 reovirus isolates. To clarify genetic diversity and molecular phylogeny of Korean reoviruses, L1, S3 and S4 genomic segments of reoviruses were amplified by RT-PCR and directly sequenced. Among 12 reovirus strains, 9 strains were type 3 and 3 strains were type 2. The L1 was highly conserved showing 91.5-100%, 94.7-100% similar ities among Korean isolates, and 77.5-97.9%, 92.6-96.8% similarities compared to other reference strains of each genotypes at nucleotide and amino acid levels, respectively. In S3 and S4 segments, 84.4-99.3%, 72.3-99% nucleotide sequence similarities and 92-99.3%, 89.1-98.4% amino acid sequence similarities among Korean isolates were observed, and 70.8-93.9%, 72.3-98.7% nucleotide sequence similarities and 81.8-100%, 88.3-97.7% amino acid sequence similarities compared with other reference strains of each genotype were observed, respectively. Phylogenetic analyses based on the S3 and S4 nucleotide sequences indicate that genotypes of reovirus are more related with geographic differences rather than host species or date of isolation.

Among the various types of diesel after-treatment device, the corona discharge reactor may be considered as a powerful tool for trapping submicron particles. But after precipitation on the electrodes occurs, the re-entrainment of particles is severe and often causes low or negative precipitation efficiency. Experiments were performed to investigate the effect of an applied voltage on the re-entrainment of soot particles from the electrodes. A co-annular laminar diffusion flame burner was used as the soot generator. When a highly negateve voltage was applied, exfoliation of the deposited soot particles and an increase in concentration of particles smaller than approximately 150 nm were observed. Turbulence induced from the negative tuft corona and sputtering caused particle re-entrainmnet from the corona wire and from plates as well. Under soot laden combustion gas, a streamer corona often occurred in the wire-cylinder reactor. Because of its transient mature, streamer corona violently increased the concentaration of reentrained particles and CO gas.

Objective To evaluate the accuracy of fine needle aspiration cytology (FNAC) of the breast at our institution and to perform quality assurance. Study design Two hundred forty-six cases with pathologic confirmation were selected and reviewed. A pathologist performed most of the aspirations at an outpatient breast clinic. We correlated cytologic and histologic findings and evaluated the influence of the size, location, grade, and pathologic subtypes and fibrosis in breast lesions on diagnostic results. Results The likelihood ratios for malignant, suspicious, atypical, benign and unsatisfactory cytologic diagnoses were 98.71, 5.48, 1.09, 0.07 and 0.55, respectively. The absolute and complete sensitivities for malignant lesions were 64.5% and 90.3%, respectively. The specificity was 71.9%. False negative and positive rates were 4.3% and 0.7%, respectively. The predictive value for a malignant cytologic diagnosis was 98.4%. The rate of unsatisfactory samples was 9.3%. The rate of concordance between cytologic and histologic diagnosis was lower for large and diffusely growing lesions (benign and malignant), for malignancies with abundant fibrosis and of unusual types and for carcinomas of low grade. All axillary and recurrent chest wall lesions were diagnosed cytologically. Cell block sections were useful in a small number of cases. Conclusion Understanding the performance and limitations of FNAC can enhance its value as a diagnostic technique in the management of breast disease.

We report here a rare case of mesenteric Castleman's disease presenting as a mesenteric mass. A 13-year-old female child was admitted to our hospital complaining of intermittent vague abdominal pain. She had hypochromic anemia, thrombocytosis and an elevated erythrocyte sedimentation rate (ESR). Ultrasonography and computed tomography indicated an intra- abdominal mass might represent a lymphoma or gastrointestinal stromal tumor or leiomyoma, but the definitive preoperative diagnosis couldn't be confirmed. The surgical resection of the mass revealed the mesenteric hyaline vascular-type Castleman's disease.

Although endoscopic thyroid surgery is gaining wide acceptance, existing endoscopic methods for thyroidectomy are blamed for the increased frequency of flap dissections and longer surgical times. More recently, transoral endoscopic thyroidectomy has overcome the limitations of previous approaches. Herein, we present our initial experience with transoral periosteal thyroidectomy (TOPOT) in cadaver and porcine models. Using these models, the surgical view was improved and had greater freedom of motion; the technique was then performed in human subjects using robotic TOPOT, which has not previously been reported.TOPOTs were performed in seven fresh human cadavers and ten live pigs. Total thyroidectomies were performed in all cadavers and pigs. After the cadaver and animal trials, four human patients underwent robotic TOPOT performed using the da Vinci® surgical system at Korea University Anam Hospital. Recurrent laryngeal nerve function, intra- and postoperative complications, and postoperative outcomes were assessed in all patients.One left lobectomy for follicular adenoma, two right lobectomies for nodular hyperplasia, and one left lobectomy with a central neck dissection for papillary thyroid microcarcinoma were performed in the human subjects using a robotic transoral periosteal approach. In three cases, paresthesia occurred in the mental nerve, but this improved within 4 weeks in all cases. No local infections occurred at the incision site or anterior neck, and no recurrent laryngeal nerve cord palsies occurred postoperatively.TOPOT may be an effective and safe approach for robotic thyroid surgery.

Objective This retrospective study investigated the characteristics of secondary hyperparathyroidism (SHPT) by examining the presence of the calcium-sensing receptor (CaSR) and the rate of cell proliferation and apoptosis in parathyroid glands. Methods Eighteen diffuse and 57 nodular hyperplastic parathyroid glands from 24 patients with SHPT were compared with 14 primary adenomas and 33 normal parathyroid glands using immunohistochemical staining of CaSR and a marker of proliferative activity (Ki67 antigen). Apoptosis was measured using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling assay. Results The mean ± SE labelling index (LI) of CaSR (12.8% ± 1.5%) in nodular hyperplasia was significantly lower than that in normal parathyroid glands (26.8% ± 0.8%), whereas the mean ± SE LI of CaSR in diffuse hyperplasia was similar to that in normal parathyroid glands (23.3% ± 1.8%). The mean ± SE LI of Ki67 antigen was significantly higher in primary adenoma and nodular hyperplasia than in normal parathyroid glands. Conclusion These results indicate that downregulation of CaSR, and a higher rate of proliferation over apoptosis, could contribute to the pathological progression of SHPT.

Although several recent studies have demonstrated the feasibility and safety of robotic adrenalectomy, it is unknown whether this procedure has advantages over the traditional laparoscopic approach. This study compared our initial experience using the da Vinci-S® robotic surgical system during laparoscopic adrenalectomy with our experience with traditional laparoscopic adrenalectomy.From October 2009 to May 2012, 23 consecutive patients (13 women, 10 men) underwent laparoscopic adrenalectomy by the same surgeon at Anam Hospital, Korea University Medical Center. Fifteen patients (9 women, 6 men) underwent robot-assisted adrenalectomy (right-sided, 4 patients; left-sided, 11 patients). Eight patients (4 women, 4 men) underwent traditional laparoscopic adrenalectomy (right-sided, 5 patients; left-sided, 3 patients). The lateral transperitoneal approach was used for all patients.There were no cases of conversion to traditional laparoscopic or open surgery. The mean operative time was longer in the robotic group (208.2 minutes, range 120-320) than the laparoscopic group (181.13 minutes, range 75-270). There were no cases of intraoperative complications or mortality. The mean hospital stay did not differ significantly between groups (robotic group, 5.86 days (SD 1.16); laparoscopic group, 6.71 days (SD 1.38)).With its magnified stereoscopic three-dimensional vision, elimination of tremor, and ability to articulate and rotate surgical instruments, the da Vinci-S® robotic system may be an ideal surgical tool for the operation of adrenal lesions. Robotic adrenalectomy appears to be a safe and effective alternative to traditional laparoscopic adrenalectomy.

Purpose: In secondary hyperparathyroidism (sHPT), it is unclear which criterion for intraoperative parathyroid hormone (ioPTH) decline performs best and whether ioPTH monitoring is sufficiently efficacious in predicting postoperative surgical cure by retrospective review. Methods: In 80 parathyroidectomies for sHPT, patients with ioPTH monitoring and follow-up PTH assay were categorized into physiologically accepted and failed groups. Receiver operating characteristic (ROC) curves were used to identify the criterion with the best performance and to determine the regression equation for prediction of surgical success. Results: There was a statistically significant difference in the percentage reduction of ioPTHs between the two groups (P ＜ 0.05). With our criterion, cure was predicted with a sensitivity of 86% and specificity that could be improved to 60% using an 85% ioPTH decrease as cut-off level when this value was compared to the Miami Criterion. There was a slightly negative correlation between the natural logarithm of percentage reduction of ioPTH and percentage reduction of PTH at follow-up (R2 = 0.109, P = 0.003). Conclusion: ioPTH measurements are a useful tool for improvement of the cure rate of operations for sHPT. Because this study aimed at 40 minutes (ioPTH3) as an optimal process in the operation, we recommend using a criterion of more than 85% ioPTH decline at 40 minutes by use of the ROC curve, and the use of the presently calculated regression equation may enable prediction of success.

This paper presents a H-plane T-junction which is designed for the feed networks of waveguide antenna array. The purpose of the T-junction is to divide power and phase equally without any reflection. To do so, we usually add an iris or a post in the junction area so that this iris or post behaves as an inductor and makes each port of the tee-junction matched [1]-[4]. By changing its shape and the location, it can divide power equally without reflection.