• Investigative Magnetic Resonance Imaging
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• v.20 no.1
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• pp.53-60
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• 2016

Purpose: To develop a technique for quantifying the $^{13}C$-metabolites by performing frequency-selective hyperpolarized $^{13}C$ magnetic resonance spectroscopy (MRS) in vitro which combines simple spectrally-selective excitation with spectrally interleaved acquisition. Methods: Numerical simulations were performed with varying noise level and $K_p$ values to compare the quantification accuracies of the proposed and the conventional methods. For in vitro experiments, a spectrally-selective excitation scheme was enabled by narrow-band radiofrequency (RF) excitation pulse implemented into a free-induction decay chemical shift imaging (FIDCSI) sequence. Experiments with LDH / NADH enzyme mixture were performed to validate the effectiveness of the proposed acquisition method. Also, a modified two-site exchange model was formulated for metabolism kinetics quantification with the proposed method. Results: From the simulation results, significant increase of the lactate peak signal to noise ratio (PSNR) was observed. Also, the quantified $K_p$ value from the dynamic curves were more accurate in the case of the proposed acquisition method compared to the conventional non-selective excitation scheme. In vitro experiment results were in good agreement with the simulation results, also displaying increased PSNR for lactate. Fitting results using the modified two-site exchange model also showed expected results in agreement with the simulations. Conclusion: A method for accurate quantification of hyperpolarized pyruvate and the downstream product focused on in vitro experiment was described. By using a narrow-band RF excitation pulse with alternating acquisition, different resonances were selectively excited with a different flip angle for increased PSNR while the hyperpolarized magnetization of the substrate can be minimally perturbed with a low flip angle. Baseline signals from neighboring resonances can be effectively suppressed to accurately quantify the metabolism kinetics.

• 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.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1627-1632
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• 2014

Background: Several studies indicated that the diagnosis season affects the prognosis of some cancers, such as examples in the prostate, colon and breast. This retrospective study aimed to investigate whether the diagnosis and recurrent season impacts the prognosis of epithelial ovarian cancer patients. Methods: From January 2005 to August 2010, 161 epithelial ovarian cancer patients were analyzed and followed up until August 2013. Kaplan-Meier survival curves and the log-rank test were used to make the survival analysis. Multivariate analysis was conducted to identify independent prognostic factors. Results: The prognostic factors of overall survival in epithelial ovarian cancer patients included age, clinical stage, pathological type, histological grade, residual disease after primary surgery, recurrent season and adjuvant chemotherapy cycles. Moreover, clinical stage, histological grade, residual disease after primary surgery, recurrent season and adjuvant chemotherapy cycles also impacted the progression-free survival of epithelial ovarian cancer patients. The diagnosis season did not have a significantly relationship with the survival of operable epithelial ovarian cancer patients. Median overall survival of patients with recurrent month from April to November was 47 months, which was longer (P < 0.001) than that of patients with recurrence month from December to March (19 months). Median progression-free survival of patients with recurrence month from April to November and December to March was 20 and 8 months, respectively (P < 0.001). Conclusion: The recurrence season impacts the survival of epithelial ovarian cancer patients. However, the diagnosed season does not appear to exert a significant influence.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.50-54
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• 1994

Spectrophotometric determination of some light lanthanide ions by flow injection method is described. Chromeazurol S forms water soluble complex with lanthanide ions in the presence of DTAB. The absorption maximum of the complexes are from 650 nm to 655 nm and the molar absorptivities were ca. $1.8{\times}10^5\;L mol^{-1}cm^{-1}$ on Tris buffer (pH 10.5). The calibration curves for Nd(III), Eu(III) and Sm(III) obtained by FIA are over the range of 0.1 to 0.6 ppm and the correlation coefficient were ca. 0.9993. The detection limits (S/N) were from 10 ppb for Nd(III) and Eu(III) to 20 ppb for Sm(III). The relative standard deviations was ${\pm}$.2% for 0.4 ppm sample. The samples throughput was ca. $50\;cm^{-1}$.

• Journal of the Korean Wood Science and Technology
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• v.33 no.4 s.132
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• pp.38-44
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• 2005

This study was carried out to investigate the combustion characteristics of flame retardant treated wood by water-soluble flame retardants which are made from mixture of aqueous solution of monoammonium phosphate, sodium borate and zinc borate. The combustion characteristics for flame retardant treated wood were carried out using thermal analysis (TGA, combustion heat) and flame retardant test (LOI, flame propagation). The results of thermal analysis and flame retardant test are as follows; 1) The sample treated by F4 showed excellent flame retardant effects in almost all of combustion characteristics. 2) From TGA curves, all the samples undergo pyrolysis and oxidation in two main discrete steps. 3) The effect of flame retardant for softwood is higher than those for hardwood, and the combustion heat has decreased with increase of the content of flame retardant. 4) LOI values are almost similar in flame retardant treated wood samples. The range of LOI is from 24 to 30. However, these values are much higher than LOI value of non-treated wood sample. 5) The blended aqueous solution had a final in the range of about pH 8.4, and a slight odor of ammonia.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.67-84
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• 1991

This study was carried out to investiagate the residual stress caused by the mismatch of thermal expansion and the bond failure resistance of alloy-porcelain specimens. The thermal expansions of alloys and porcelains were measured by using a straight push-rod dilatometer. Porcelain glass transition temperatures, thermal expansion coefficients, and thermal compatibility indices were derived from length-versus-temperature curves. Strain gauges were used to experimentally determine the Young's moduli of porcelains, the residual stresses of porcelain surface, and tensile bond strengths of the specimens of simulated porcelain metal crown. The obtained results were as follows: 1. The coefficients of thermal expansion for alloys were the minimum of $13.53\mu/^{\circ}C$ and the maximum of $20.11\mu/^{\circ}C$ in the range of $100\sim600^{\circ}C$ and those for porcelains were the minimum of $7.72\mu/^{\circ}C$ and the maximum of $31.24\mu/^{\circ}C$ in the range of $100\sim500^{\circ}C$. 2. The glass transition temperature of porcelains exhibited the same value without my relation to the healing rate, and the thermal disharmony of porcelain and alloy was more affected by porcelains than by the alloys. 3. The Young's moduli of body porcelains were larger than those of opaque porcelains(P<0.01) 4. It seemed that the residual stresses of porcelain surfaces in the porcelainalloy systems were more affected by porcelains than by alleys. 5. The bond strengths of the procelain-base metal alloy systems were larger than those of the porcelain-precious metal alloy systems. The fracture strengths of porcelain surfaces showed significant difference between porcelains (P<0.05).

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.89-93
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• 2016

Background: Limited data are available regarding the impact of time duration between chemoradiation (CRT) and surgery on pathological complete response (PCR). A PCR translates into better overall and disease free survival. The objective of this study was to determine effect of time duration on outcome after preoperative CRT in rectal cancer. Materials and Methods: A retrospective review of patients undergoing operations for rectal adenocarcinoma between January 2005 and December 2010 was performed. Patients were divided in two groups: Group 1 underwent surgery in ${\leq}8weeks$ post neoadjuvant CRT and Group 2 after 8 weeks. Patient characteristics, surgical procedure, histopathological details and number of loco-regional and distant failures were compared. Expected 5 year overall survival and disease free survival was calculated using Kaplan Meier curves and significance was determined using the log rank test. Results: There were 66 patients in group 1 and 93 in group 2. No significant difference in PCR was observed between the two. However, estimated 5 year DFS was significantly higher in Group 1 (66.7%) as compared to Group 2 (53.8%) (P=0.04). Estimated overall 5 year overall survival was not significantly different at 68.2% versus 54.3% (P= 0.09). Conclusions: Delaying surgery more than 8 weeks after preoperative CRT does not impact for PCR in rectal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3037-3046
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• 2012

The diffuse large B-cell lymphoma (DLBCL) encompasses two major groups of tumors with uneven survival outcomes - germinal center B-cell (GCB) and non-germinal center B-cell (non-GCB). In the present study, we investigated the expression of GCB markers (BCL-6 and CD10) and non-GCB markers (CD138 and MUM-1) in an effort to evaluate their prognostic value. Paraffin-embedded tumor biopsies of 46 Jordanian DLBCL patients were analyzed, retrospectively, by immunohistochemistry to investigate the expression of BCL-6, CD10, CD138 and MUM-1. In addition, survival curves were calculated with reference to marker expression, age, sex and nodal involvement. Positive expression of BCL-6, CD10, CD138 and MUM-1 was shown in 78%, 61%, 39% and 91% of the cases, respectively, that of BCL-6 being associated with better overall survival (p = 0.02), whereas positive CD138 was linked with poor overall survival (p = 0.01). The expression of CD10 and MUM-1 had no impact on the overall survival. Among the clinical characteristics studied, diagnosis at an early age, nodal involvement and maleness were associated with a higher overall survival for DLBCL patients. Our results underline the importance of BCL-6 as a marker of better prognosis and CD138 as a marker of poor prognosis for DLBCL patients.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1314-1319
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• 2008

Fatigue reliability problems are nowadays actively considered in the design of mechanical components. Recently, Dimension Reduction Method using Kriging approximation (KDRM) was proposed by the authors to efficiently calculate statistical moments of the response function. This method, which is more tractable for its sensitivity-free nature and providing the response PDF in a few number of analyses, is adopted in this study for the reliability analysis. Before applying this method to the practical fatigue problems, accuracies are studied in terms of parameters of the KDRM through a number of numerical examples, from which best set of parameters are suggested. In the fatigue reliability problems, good number of experimental data are necessary to get the statistical distribution of the S-N parameters. The information, however, are not always available due to the limited expense and time. In this case, a family of curves with prediction interval, called P-S-N curve, is constructed from regression analysis. Using the KDRM, once a set of responses are available at the sample points at the mean, all the reliability analyses for each P-S-N curve can be efficiently studied without additional response evaluations. The method is applied to a spring design problem as an illustration of practical applications, in which reliability-based design optimization (RBDO) is conducted by employing stochastic response surface method which includes probabilistic constraints in itself. Resulting information is of great practical value and will be very helpful for making trade-off decision during the fatigue design.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.254-259
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• 2009

An experiment was conducted to evaluate the effect of different levels of extracted pigment from Dietzia natronolimnaea biomass as a source of canthaxanthin in comparison with synthetic canthaxanthin on egg yolk pigmentation. The experiment used a completely randomized design (CRD). A total of 63 laying hens, 68 weeks old, were used and the birds were allotted to 7 dietary treatments with each treatment replicated three times with three hens per replicate. Treatments consisted of 3 levels of synthetic canthaxanthin (4, 8 and 16 ppm), 3 levels of extracted pigment from D. natronolimnaea biomass (4, 8 and 16 ppm) and control. Changes in yolk color were determined in 2 eggs taken at random, during the four week experimental period from each replicate. Supplementation of extracted pigment from D. natronolimnaea biomass had a significant effect on the color of egg yolks (p<0.05). Yolk color score of the control group was 6.83 in BASF color fan and the yolk color score of different extracted pigment levels was 11.00, 12.50 and 14.50, respectively. The yolk colors of different levels of synthetic canthaxanthin were 12.00, 14.00 and 15.00, respectively. The effect of pigment supplementation on egg yolk color was better explained by polynomial response curves. The $R_{2}$ indicated that for 3 supplementation levels of each pigment studied, over 90% of the color variation could be explained by the pigment concentration. The egg yolk color after 15 and 30 days of storage was not significantly different, but boiling reduced egg yolk color significantly (p<0.05).