• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.4
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• pp.366-373
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• 2013

This paper discusses the singly curved phased reflector for reduced RCS pattern, which has minimized RCS level at boresight with a null by phase cancelation and the lowered RCS level of main beam by splitting the main beam into multi directions. Considering the reduced level of boresight and main beam compared to the same sized reference PEC, this proposed multi-beam reflector can be adopted in the mono-static radar and the bi-static radar environment. The proposed reflector is a multi-beam reflector, which has different phase distributions at each row for different steering angle. It is designed through an intermediate stage of a single and dual-beam reflector. The behaviors of the designed reflectors are verified through full-wave simulation and experiment. The reflectors are designed in the frequency of 10 GHz and it has a size $240{\times}180mm^2$($8{\times}6\;{\lambda}^2$) with the curvature k=3.3. From the measured results, the proposed reflectors reduce the reflected power by 17 dB at boresight.

• Tuberculosis and Respiratory Diseases
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• v.81 no.4
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• pp.311-318
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• 2018

Background: The aim of this study was to examine the influence of body mass index (BMI) on the development of acute kidney injury (AKI) in critically ill patients in intensive care unit (ICU). Methods: Data of patients admitted to medical ICU from December 2011 to May 2014 were retrospectively analyzed. Patients were classified into three groups according to their BMI: underweight (< $18.5kg/m^2$), normal ($18.5-24.9kg/m^2$), and overweight (${\geq}25kg/m^2$). The incidence of AKI was compared among these groups and factors associated with the development of AKI were analyzed. AKI was defined according to the Risk, Injury, Failure, Loss of kidney function, and End-stage (RIFLE) kidney disease criteria. Results: A total of 468 patients were analyzed. Their mean BMI was $21.5{\pm}3.9kg/m^2$, including 102 (21.8%) underweight, 286 (61.1%) normal-weight, and 80 (17.1%) overweight patients. Overall, AKI occurred in 82 (17.5%) patients. The overweight group had significantly (p<0.001) higher incidence of AKI (36.3%) than the underweight (9.8%) or normal group (15.0%). In addition, BMI was significantly higher in patients with AKI than that in those without AKI ($23.4{\pm}4.2$ vs. $21.1{\pm}3.7$, p<0.001). Multivariate analysis showed that BMI was significantly associated with the development of AKI (odds ratio, 1.893; 95% confidence interval, 1.224-2.927). Conclusion: BMI may be associated with the development of AKI in critically ill patients.

• Biomedical Science Letters
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• v.5 no.1
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• pp.59-66
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• 1999

To evaluate the effect of repeated treatment of xylene on its metabolism, m-xylene (0.25 ml of 50% in olive oi1/100 g body weight) has been intraperitoneally given to the rats 1, 4, 8, 12 and 16 times every other day. m-Xylene was once more administered to the animals after 24 hrs since last injection of it. And then the animals were sacrificed after 24 hrs. Four times xylene treated rats showed the significantly elevated urinary m-methylhippuric acid, compared to those treated with the single dose of m-xylene with the continued similiar high levels of urinary m-methylhippuric acid up to the animals pretreated 12 times and then those treated 16 times defined the significantly decreased urinary m-methylhippuric acid compared to those treated 12 times. On the other hand, hepatic aniline hydroxylase and alcohol dehydrogenase activities demonstrated a gradual increase from the first group to the 12 times xylene-treated animals, but those treated 16 times showed the significantly decreased value compared with the 12 times treated-group. And aldehyde dehydrogenase activities in rats treated with m-xylene 8, 12 or 16 times were significantly decreased compared to those pretreated one or four times. In the early stage of xylene administration, proliferation of SERs were seen whereas SERs were decreased and RERs were clearly increased in xylene-treated rats 16 times. These results indicate that the frequency of xylene injection may influence upon the changes in xylene metabolite, m-methylhippuric acid and it may be due to induction of xylene metabolizing enzymes.

• Molecular & Cellular Toxicology
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• v.2 no.4
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• pp.236-243
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• 2006

Microarray analysis of gene expression has become a powerful approach for exploring the biological effects of drugs, particularly at the stage of toxicology and safety assessment. Acetaminophen (APAP) has been known to induce necrosis in liver, but the molecular mechanism involved has not been fully understood. In this study, we investigated gene expression changes of APAP using microarray technology. APAP was orally administered with a single dose of 50 mg/kg or 500 mg/kg into ICR mice and the animals were sacrificed at 6, 24 and 72 h of APAP administration. Serum biochemical markers for liver toxicity were measured to estimate the maximal toxic time and hepatic gene expression was assessed using high-density oligonucleotide microarrays capable of determining the expression profile of >30,000 well-substantiated mouse genes. Significant alterations in gene expression were noted in the liver of APAP-administered mice. The most notable changes in APAP-administered mice were the expression of genes involved in apoptosis, cell cycle, and calcium signaling pathway, cystein metabolism, glutatione metabolism, and MAPK pathway. The majority of the genes upregulated included insulin-like growth factor binding protein 1, heme oxygenase 1, metallothionein 1, S100 calcium binding protein, caspase 4, and P21. The upregulation of apoptosis and cell cycle-related genes were paralleled to response to APAP. Most of the affected gene expressions were returned to control levels after 72 hr. In conclusion, we identified potential hepatotoxicity makers, and these expressions profiling lead to a better understanding of the molecular basis of APAP-induced hapatotoxicity.

• Archives of Plastic Surgery
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• v.47 no.6
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• pp.583-589
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• 2020

Background Reduction mammoplasty or mastopexy is performed as an additional balancing procedure in patients with large or ptotic breasts who undergo breast-conserving surgery (BCS). Radiation therapy on breasts that have undergone surgery may result in changes in the volume. This study presents a comparative analysis of patients who received post-BCS balancing procedures to determine whether volume changes were larger in breasts that received radiation therapy than on the contralateral side. Methods Thirty-six participants were selected among patients who received BCS using the inverted-T scar technique between September 2012 and July 2017, were followed up for 2 or more years, and had pre-radiation therapy computed tomography images and post-radiation therapy images taken between 12 and 18 months after completion. The average age of the participants was 53.5 years, their average body mass index was 26.62 kg/㎡. Results The pre- and post-radiation therapy volumes of the breasts receiving BCS were 666.08±147.48 mL and 649.33±130.35 mL, respectively. In the contralateral breasts, the volume before radiation therapy was 637.69±145.72 mL, which decreased to 628.14±166.41 mL after therapy. The volume ratio of the affected to the contralateral breasts was 1.05±0.10 before radiation therapy and 1.06±0.12 after radiation therapy. Conclusions The ratio of the volume between the two breasts immediately after surgery and at roughly 18 months postoperatively was not significantly different (P=0.98). For these reasons, we recommend a simultaneous single-stage balancing procedure as a reasonable option for patients who require radiation therapy after BCS without concerns regarding volume change.

• Journal of Internet Computing and Services
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• v.21 no.2
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• pp.81-90
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• 2020

The purpose of this study is to study how to apply block-chain technology to prevent data forgery and alteration in the defense sector of AI(Artificial intelligence). AI is a technology for predicting big data by clustering or classifying it by applying various machine learning methodologies, and military powers including the U.S. have reached the completion stage of technology. If data-based AI's data forgery and modulation occurs, the processing process of the data, even if it is perfect, could be the biggest enemy risk factor, and the falsification and modification of the data can be too easy in the form of hacking. Unexpected attacks could occur if data used by weaponized AI is hacked and manipulated by North Korea. Therefore, a technology that prevents data from being falsified and altered is essential for the use of AI. It is expected that data forgery prevention will solve the problem by applying block-chain, a technology that does not damage data, unless more than half of the connected computers agree, even if a single computer is hacked by a distributed storage of encrypted data as a function of seawater.

• Journal of fish pathology
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• v.30 no.2
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• pp.107-114
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• 2017

We evaluated the anti-parasitic efficacy of hydrogen peroxide against a scuticociliate Miamiensis avidus in olive flounder Paralichthys olivaceus. In vitro tests showed that hydrogen peroxide above 50 mg/l is effective for killing M. avidus. In vivo effects were assessed in olive flounder after immersion infection with $2.8{\times}10^3M.\;avidus/ml$ for 2 days, and in naturally infected fish obtained from Jeju area farms. Bathing treatment with 100 and 200 mg/l hydrogen peroxide showed markedly higher survival rates of olive flounder than control groups (p<0.05). The number of live M. avidus in fish tissues were reduced for 3 days in naturally-infected fish after a single bath. In conclusion, hydrogen peroxide can be a good therapeutant particularly in the early stage of M. avidus infection.

• Clinical and Experimental Reproductive Medicine
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• v.47 no.3
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• pp.213-220
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• 2020

Objective: The aim of this study was to explore the potential adverse effect of spontaneously decreasing serum estradiol (SE) levels on in vitro fertilization (IVF) outcomes. Methods: This retrospective single-subject study analyzed IVF cycles conducted at a hospital IVF unit between 2010 and 2017. Overall, 2,417 cycles were analyzed. Only cycles with spontaneously decreasing SE before human chorionic gonadotropin (hCG) triggering were included. Each patient served as her own control, and subsequent cycles were analyzed for recurrent SE decreases. The main outcome was the number of oocytes retrieved. Results: Cycle characteristics were similar between the study (SE decrease) and control groups, with the exception of the median SE on the day of hCG triggering (899.7 pg/mL; interquartile range [IQR], 193-2,116 pg/mL vs. 1,566.8 pg/mL; IQR, 249-2,970 pg/mL; p< 0.001). The study group, relative to the control group, had significantly fewer total oocytes (5 [IQR, 2-9] vs. 7 [IQR, 3-11]; p= 0.002) and significantly fewer metaphase II (MII) oocytes (3 [IQR, 1-6] vs. 4 [IQR, 2-8]; p= 0.001) retrieved. The study group had fewer cleavage-stage embryos than the control cycles (3 [IQR, 1-6] vs. 4 [IQR, 2-7]; p= 0.012). Compared to cycles with a ≤ 20% SE decrease, cycles with a > 20% decrease had significantly fewer total and MII oocytes retrieved. SE decrease recurred in 12% of patients. Conclusion: A spontaneous decrease in SE levels adversely affected IVF outcomes, with a linear correlation between the percentage decrease and the number of oocytes retrieved. SE decrease can repeat in later cycles.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1169-1174
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• 2016

Purpose: To review clinical characteristics, treatment outcomes and prognostic factors in patients with parotid gland tumors treated with surgery and postoperative radiotherapy. Materials and Methods: We retrospectively reviewed 69 patients with parotid gland tumors, with a median follow-up of 52 months (range, 2-228 months). and a median radiotherapy dose of 60Gy (range, 30-69 Gy). Results: There were 24 (35%) females and 45 (65%) males, at a ratio of 1/1.9. Median age at presentation was $58.9{\pm}17.2$ (range 13-88) years. The most common histology was adenoid cystic carcinoma (33%) and mucoepidermoid carcinoma (28%). The mean overall survival (OS) was $65.3{\pm}8$ (95% confidence interval [CI], 49.6-81.1) months and the median overall survival was $40.0{\pm}7$ (95% CI, 26.2-53.7) months. The -1, -3, -5 and -10 year OS rates were 78%, 52.4%, 35.3% and 19.6% respectively. The mean disease free survival (DFS) was $79.2{\pm}10$ (95% CI, 59.3-97.1) months and the median disease free survival was $38{\pm}13$ (95% CI, 7.05-88.7) months. The -1,-3,-5 and -10 year DFS rates were 71.9%, 50.1%, 43.7% and 30.1% respectively. On univariate analysis, the OS was significantly better with female sex (p<0.005), < 50 age (p<0.021), T stage (p<0.0001), absence of lymph node involvement (p<0.0001), lower tumor grade (p<0.0001), absence of lymphovascular invasion (p<0.002), absence of perineural invasion (p<0.0001), absence of extracapsuler extension (p<0.0001), surgical margin negativity (p<0.006), ${\leq}60Gy$ radiotherapy dose (p<0.0001) and absence of distant metastasis (p<0.027). Conclusions: Employing existing standards of postoperative radiotherapy is a possible treatment that was found to be mainly effective in patients with parotid gland carcinomas.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6267-6272
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• 2015

Background: Extra nodal lymphoma (ENL) constitutes about 33 % of all non-Hodgkin's lymphoma. 18-28% develops in the head and neck region. A multimodality treatment with multi-agent chemotherapy (CT) and radiotherapy (RT) is considered optimum. Materials and Methods: We retrieved the treatment charts of patients of HNENL treated in our institute from 2001-2012. The charts were reviewed and the demographic, treatment details and outcome of HNENL patients were retrieved using predesigned pro-forma. Results: We retrieved data of 75consecutive patients HNENL. Median age was 47years (Range: 8-76 years). Of the 75 patients 51 were male and 24 were female. 55patients were evaluable. The patient and tumor characteristics are summarized in Table 1. All patients were staged comprehensively with contrast enhanced computed tomography of head, neck, thorax, abdomen, pelvis and bone marrow aspiration and biopsy 66 patients received a combination multi-agent CT with CHOP being the commonest regimen. 42 patients received 4 or lesser number of cycles of chemotherapy whereas 24received more than 4 cycles chemotherapy. Post radiotherapy, 41 out of 42 patients had a complete response at 3 months. Only 21patients had a complete response after chemotherapy. All patients received radiation (mostly involved field radiation) as a part of the treatment. The median radiation dose was 45 Gray (Range: 36 Gray-50 Gray). The radiation was planned by 2D fluoro simulation based technique in 37cases and by 3 Dimensional conformal radiation therapy (3DCRT) in 36 cases. Two patients were planned by the intensity modulated radiation therapy (IMRT) technique. IMRT was planned for one thyroid and one nasal cavity primary. 5 patients experienced relapse after a median follow up of 19 months. The median survival was not reached. The estimated two and three year survival were 92.9% (95%CI- 68.6- 95.35) and 88% (95%CI- 60.82 - 92.66) respectively. Univariate analysis revealed higher stage and poorer baseline performance status to be significantly associated with worse progression free survival. 5 patients progressed (relapse or primary disease progression) after treatment. Of the 5 patients, two patients were primary orbital NHL, two patients had NHL nasal cavity and one was NHL thyroid. Conclusions: Combined modality treatment in HNENL confers excellent disease control with acceptable side effects.