• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4045-4050
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• 2012

Objective: The impact of ablative oral cancer surgery was studied, with particular reference to recurrence and nodal metastasis, to assess survival probability and prognostic indicators and to elucidate if ethnicity influences the survival of patients. Methods: Patients who underwent major ablative surgery of the head and neck region with neck dissection were identified and clinical records were assessed. Inclusion criteria were stage I-IV oral and oropharyngeal malignancies necessitating resection with or without radiotherapy from 2004 to 2009. All individuals had a pre-operative assessment prior to the surgery. The post operative assessment period ranged from 1 year to 5 years. Survival distributions were analyzed using Kaplan-Meier curves. Results: 87 patients (males:38%; females:62%) were included in this study, with an age range of 21-85 years. Some 78% underwent neck dissections while 63% had surgery and radiotherapy. Nodal recurrence was detected in 5.7% while 20.5% had primary site recurrence within the study period. Kaplan-Meier survival analysis revealed that the median survival time was 57 months. One year overall survival (OS) rate was 72.7% and three year overall survival rate dropped to 61.5%. On OS analysis, the log-rank test showed a significant difference of survival between Malay and Chinese patients (Bonferroni correction p=0.033). Recurrence-free survival (RFS) analysis revealed that 25% of the patients have reached the event of recurrence at 46 months. One year RFS rate was 85.2% and the three year survival rate was 76.1%. In the RFS analysis, the log-rank test showed a significant difference in the event of recurrence and nodal metastasis (p<0.001). Conclusion: Conservative neck is effective, in conjunction with postoperative radiotherapy, for control of neck metastases. Ethnicity appears to influence the survival of the patients, but a prospective trial is required to validate this.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.403-409
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• 2005

Mature nodal segments of 2-year-old greenhouse stock plant were cultured on Murashige and Skoog basal medium supplemented with the different kinds and various concentrations of cytokinins to produce multiple shoots in in vitro condition. The most adventitious shoots were produced from excised ends of nodal segments. The highest average number $(24.6\;{\pm}\;4.6)$ of shoots was produced with the combination of BA 1.0mg/L and TDZ 0.1mg/L in MS medium. In addition, several shoots were formed from lenticels of bark cambium with the same treatment. These concentrations promoted high shooting capability upto $94.6\%$ and NAA was the best cytokinin among five different PGR sources.

• Korean Journal of Plant Tissue Culture
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• v.21 no.3
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• pp.145-150
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• 1994

This study was conducted to determine the effects of 3 cytokinins (BA,2iP and kinetin) and their concentrations (0, 0.1, 0.5, 1.0, and 2.0 mg/L) on multiple shoot production of Citrus spp. 'Sambokam' and 'Byungkyool' by nodal culture. Nodal explants were obtained from in vitro germinated seedlings of both cultivars. 'Sambokam' produced more multiple shoots than did 'Byungkyool' by nodal culture. Among the 3 cytokinins tested in this study BA supplemented in semi-solid MS basal medium was the most effective stimulator for multiple shoot production, and an optimal concentration was determined to be 1.0 mg/L. Shoot elongation and root formation were inhibited by increasing cytokinin concentration, regardless of cytokinin types. BA at 1.0 mg/L produced the most multiple shoots and the highest number of leaves in 'Sambokam', whereas any cytokinin and concentration studied in this experiment did not affect any scored variables such as shoot and leaf numbers, etc. in 'Byungkyool'.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.5
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• pp.849-863
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• 1992

A very simple and computationally efficient numerical method is developed for the free vibration of isotropic and orthotropic composite triangular plates. A set of two-dimensional simple series functions is used as an admissible displacement functions in the Rayleigh-Ritz method to obtain the natural frequencies, nodal patterns and mode shapes for the plates. From the prescribed starting function satisfying only the geometric boundary conditions, the higher terms in the series functions are constructed with adding order of polynominal. Natural frequencies, nodal patterns and mode shapes are obtained for right triangular plates with three different support conditions. The obtained numerical results are presented, and the isotropic and some orthotropic cases are verified with other numerical methods in the liternature.

• Korean Journal of Head & Neck Oncology
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• v.15 no.2
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• pp.166-171
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• 1999

Background and Objectives: The aim of our study was to describe the appearance of recurrent and residual lesions in the head and neck tumors, and to evaluate the usefullness of CT and MRI. Materials and Methods: CT(n=42) and MRI(n=4) of 44 patients with recurrent head and neck tumors were reviewed retrospectively. Primary tumor sites were larynx/hypopharynx in 15, oral cavity/floor of mouth in 13, base of tongue/tonsil in 5, nasopharynx in 4, palate in 2, and others in 5 patients. Therapeutic modalities included sugery and radiotherapy in 23, radiotherapy in 11, surgery in 5, chemotherapy and radiotherapy in 4, and chemotherapy in 1 patient. Results: The patterns of tumor recurrence were nodal recurrence(n=17), primary tumor bed recurrence combined with nodal recurrence(n=12), primary tumor bed recurrence(n=10) and residual primary tumors(n=5). The most common appearance of residual/recurrent primary tumor on CT was focal or diffuse heterogenous mass with or without surrounding fat or muscle infiltration(25/27). On MRI, the recurrent lesions showed intermediate signal intensity on T1 weighted image and high signal intensity on T2 weighted image with heterogenous enhancement in the most cases(n=3). 38 out of 44 nodal recurrences(86%) which had been pathologically or clinically proved were more than 1 cm in diameter or contained central low density on CT scan. Conclusion: Although CT and MRI findings of recurrent and residual tumors of the head and neck were nonspecific, in the majority the lesions manifested as a mass at primary tumor bed and/or nodal disease including contralateral side of the neck. And CT and MRI are valuable for revealing above lesions.

• Nuclear Engineering and Technology
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• v.21 no.3
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• pp.193-204
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• 1989

This paper develops a new method for reconstructing neutron flux distribution, that is based on the maximum entropy Principle in information theory. The Probability distribution that maximizes the entropy Provides the most unbiased objective Probability distribution within the known partial information. The partial information are the assembly volume-averaged neutron flux, the surface-averaged neutron fluxes and the surface-averaged neutron currents, that are the results of the nodal calculation. The flux distribution on the boundary of a fuel assembly, which is the boundary condition for the neutron diffusion equation, is transformed into the probability distribution in the entropy expression. The most objective boundary flux distribution is deduced using the results of the nodal calculation by the maximum entropy method. This boundary flux distribution is then used as the boundary condition in a procedure of the imbedded heterogeneous assembly calculation to provide detailed flux distribution. The results of the new method applied to several PWR benchmark problem assemblies show that the reconstruction errors are comparable with those of the form function methods in inner region of the assembly while they are relatively large near the boundary of the assembly. The incorporation of the surface-averaged neutron currents in the constraint information (that is not done in the present study) should provide better results.

• Journal of Gastric Cancer
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• v.17 no.2
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• pp.186-191
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• 2017

The role of nodal station No. 14v (along the superior mesenteric vein) in lymphadenectomy for distal gastric cancer remains elusive. A 73-year-old woman underwent endoscopic submucosal dissection for gastric cancer, and was referred to our division for additional surgery because of pathologically non-curative resection. A laparoscopic distal gastrectomy with D1+ dissection was performed, with a final diagnosis of pT1bN1M0, Stage IB (2 nodal metastases to No. 6). Four months post-surgery, abdominal computed tomography revealed a 14-mm solitary nodule along the superior mesenteric vein. The lesion was excised and pathologically identified as a lymph node metastasis. Adjuvant chemotherapy with tegafur-gimeracil-oteracil potassium (S-1) was administered for the metastasis. Presently the patient survives without recurrence, 5.5 years after the second operation. Our findings suggest that there is lymphatic flow from the No. 6 to the No. 14v nodal station. Some patients with a No. 6 metastasis may benefit from a No. 14v lymphadenectomy, even in early-staged disease.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.6
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• pp.529-539
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• 2008

Background and Purpose : Oral squamous cell carcinoma (OSCC) is one of the most aggressive tumors of the head and neck area. OSCC is known to preferentially metastasize via lymphatic system, and resulting cervical lymph node metastasis is the most reliable of treatment failure. But the biological mechanism of the regional nodal metastasis is not clear. So, we determined metastasis-related factors in orthotopic nude mouse models of OSCC. Experimental Design : Two cell lines-KB and YD-10B cells, established from human oral mucosal squamous cell carcinoma, were xenografted into the tissue space of athymic murine mouth floor. The mice were followed for tumor development and growth, the murine tumors were examined histopathologically for local invasion or regional or distant metastasis. Finally, we performed immunohistochemical assays with antiepithelial growth factor (EGF), EGF receptor (EGFR), phosphorylated EGFR (pEGFR), and anti-vascular endothelial growth factor (VEGF), VEGF receptor (VEGFR)-2, phosphorylated VEGFR-2/3 (pVEGFR-2/3) antibodies. We also determined the microvessel density. Results : Transplantation of human OSCC tumor cells into the mouth floor successfully resulted in the formation of orthotopic tumors. KB cell line showed significantly higher tumor proliferation and higher nodal metastatic potential than YD-10B cell line. Furthermore, immunohistochemical staining demonstrated higher expression of EGFR/pEGFR, VEGF, and pVEGFR-2/3 as well as higher microvessel density in KB murine tumors than in YD-10B murine tumors. Conclusion : An orthotopic model of OSCC in athymic mice was established which copies the cervical lymph nodal metastasis of human OSCC. Our mouth floor model should facillitate the understanding of the molecular pathogenesis of cervical nodal metastasis of OSCC.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.1
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• pp.85-94
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• 2018

For the design of wind-power facilities, the highest and lowest astronomical tides (HAT and LAT, respectively) are needed for the tidal-water levels regarding international designs; however, the approximate highest high water and approximate lowest low water AHHW and ALLW, respectively, have been used in Korea. The HAT and LAT in the wind-farm test-bed sea should be estimated to satisfy the international standard. In this study, the HAT and LAT are therefore estimated using the hourly tidal-elevation data of the Eocheongdo, Anmado, Younggwang, Gunsan, Janghang, and Seocheon tidal-gauging stations that are located in the adjacent coastal sea. The nodal variation patterns of the major lunar components, such as $M_2$, $O_1$, and $K_1$ are analyzed to check the expected long-term lunar cycle, i.e., 18.61 year's nodal-variation patterns. The temporal amplitude variations of the $M_2$, $O_1$, and $K_1$ clearly show the 18.61-years periodic patterns in the case of the no-nodal correction condition. In addition, the suggested HAT and LAT elevations, estimated as the upper and lower confidence limits of the yearly HAT and LAT elevations, are 50 cm greater than the AHHW and 40 cm lower than the ALLW, respectively.

• Structural Engineering and Mechanics
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• v.73 no.3
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• pp.339-351
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• 2020

Earthquakes are natural disasters that cause serious social disruptions and economic losses. In particular, they have a significant impact on critical lifeline infrastructure such as urban water transmission networks. Therefore, it is important to predict network performance and provide an alternative that minimizes the damage by considering the factors affecting lifeline structures. This paper proposes a probabilistic reliability approach for post-hazard flow analysis of a water transmission network according to earthquake magnitude, pipeline deterioration, and interdependency between pumping plants and 154 kV substations. The model is composed of the following three phases: (1) generation of input ground motion considering spatial correlation, (2) updating the revised nodal demands, and (3) calculation of available nodal demands. Accordingly, a computer code was developed to perform the hydraulic analysis and numerical modelling of water facilities. For numerical simulation, an actual water transmission network was considered and the epicenter was determined from historical earthquake data. To evaluate the network performance, flow-based performance indicators such as system serviceability, nodal serviceability, and mean normal status rate were introduced. The results from the proposed approach quantitatively show that the water network is significantly affected by not only the magnitude of the earthquake but the interdependency and pipeline deterioration.