• Journal of Navigation and Port Research
• /
• v.28 no.10 s.96
• /
• pp.875-879
• /
• 2004

In this paper, sub-harmonic pumped(SHP) mixer using anti-parallel diode pair(APDP) is designed for 5 GHz band wireless communication system. Conventional mixers mix LO with RF, and obtain IF signal from the difference between LO and RF. As the frequency increase, LO signal requires higher LO power, better phase noise characteristics, more stable La. However, using APDP, the SHP mixer mixes the 2nd harmonics of LO signal. Therefore, the SHP mixer has an advantage that the LO signal frequency required for IF signal is reduced at half value of LO fundamental frequency. When LO power is 3 dBm, the conversion loss of manufactured SHP mixer is 12.83 dB. The isolation of LO/IF, 2LO/IF, RF/1F and LO/RF is 39.17 dB, 58 dB, 34 dB, and 67.9 dB. respectively. For this case, IP3 at input is 8 dBm.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.8
• /
• pp.3989-3995
• /
• 2016

Background: Childhood acute lymphoblastic leukemia (ALL) is a heterogeneous genetic disease and its etiology remains poorly understood. Recent genome wide association and replication studies have highlighted specific polymorphisms contributing to childhood ALL predispositions mostly in European populations. It is unclear if these observations generalize to other populations with a lower incidence of ALL. The current case-control study evaluated variants in ARID5B (rs7089424, rs10821936), IKZF1 (rs4132601) and CEBPE (rs2239633) genes, which appear most significantly associated with risk of developing childhood B-lineage ALL. Materials and Methods: Using TaqMan assays, genotyping was conducted for 162 de novo B-lineage ALL cases and 150 unrelated healthy controls in India. Appropriate statistical methods were applied. Results: Genotypic and allelic frequencies differed significantly between cases and controls at IKZF1-rs4132601 (p=0.039, p=0.015) and ARID5B-rs10821936 (p=0.028, p=0.026). Both rs10821936 (p=0.019; OR 0.67; 95% CI=0.47-0.94) and rs4132601 (p=0.018; OR 0.67; 95%CI 0.48-0.94) were associated with reduced disease risk. Moreover, gender-analysis revealed male-specific risk associations for rs10821936 (p=0.041 CT+CC) and rs4132601 (p=0.005 G allele). Further, ARID5B-rs7089424 and CEBPE-rs2239633 showed a trend towards decreased disease risk but without significance (p=0.073; p=0.73). Conclusions: Our findings provide the first evidence that SNPs ARID5B-rs10821936 and IKZF1-rs4132601 are associated with decreased B-lineage ALL susceptibility in Indian children. Understanding the effects of these variants in different ethnic groups is crucial as they may confer different risk of ALL within different populations.

• Journal of IKEEE
• /
• v.8 no.1 s.14
• /
• pp.79-85
• /
• 2004

In this paper, Sub harmonic mixer using anti-parallel diode pair is designed for 5.8 GHz Wireless LAN. Conventional mixers mix LO with RF and obtain IF signal from the difference between LO and RF. As frequency increase, LO signal is required increasing LO power, better phase noise, stable LO. But, using APDP, the SHP mixer mix the harmonics of LO signal. Therefore, Sub harmonic mixer is advantage that necessary LO signal frequency was used to operate the 1/2. When LO power is 3 dBm, the conversion loss of manufactured SHP mixer is 12.83 dB. The isolation of LO/IF, 2LO/IF, RF/IF and LO/RF is 39.17 dB, 58 dB, 34 dB, 67.9 dB. And IIP3 is 8 dBm.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.3
• /
• pp.1553-1564
• /
• 2016

Identification of novel therapeutics in glioblastoma remains crucial due to the devastating and infiltrative capacity of this malignancy. The current study was aimed to appraise effect of arsenic trioxide (ATO) in U87MG cells. The results demonstrated that ATO induced apoptosis and impeded proliferation of U87MG cells in a dose-dependent manner and also inhibited classical NF-${\kappa}B$ signaling pathway. ATO further upregulated expression of Bax as an important proapoptotic target of NF-${\kappa}B$ and also inhibited mRNA expression of survivin, c-Myc and hTERT and suppressed telomerase activity. Moreover, ATO significantly increased adhesion of U87MG cells and also diminished transcription of NF-${\kappa}B$ down-stream targets involved in cell migration and invasion, including cathepsin B, uPA, MMP-2, MMP-9 and MMP-14 and suppressed proteolytic activity of cathepsin B, MMP-2 and MMP-9, demonstrating a possible mechanism of ATO effect on a well-known signaling in glioblastoma dissemination. Taken together, here we suggest that ATO inhibits survival and invasion of U87MG cells possibly through NF-${\kappa}B$-mediated inhibition of survivin and telomerase activity and NF-${\kappa}B$-dependent suppression of cathepsin B, MMP-2 and MMP-9.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.1 s.343
• /
• pp.127-132
• /
• 2006

This paper presents a dual-mode amplifier which operates as amplifier or frequency multiplier according to the input frequency. It satisfies the 802.11a/b/g frequency band of wireless LAN standard. A conventional dual-band wireless LAN transmitter consists of the separating power amplifiers operating at each frequency band, but the proposed dual-mode amplifier operates as an amplifier for the 802.11b/g signal and as a frequency multiplier for the 802.11a signal according to each LAN bias condition. The amplifier mode shows the gain of 13dB, the PldB of 17dBm and second harmonic suppression of below -37dBc. And the frequency-doubler mode shows the gain of 3.3dB, the output power of 7.3dBm and third harmonic suppression of below -50dBr.

• ALGAE
• /
• v.17 no.1
• /
• pp.53-58
• /
• 2002

The transition of plant life from aquatic algae to land to land plants was one of the major events in the history of life. However, in hypothesizing the exact evolutionary path of the transition, limited shared phenotypic characters in aquatic algae and land plants (embryophytes) have been a major hinderance. Chloroplast genomes contain characters useful in tracing evolutionary histories. Embryophyte chloroplast genomes are distinguished from algal cpDNAs by having over 20 group Ⅱ introns, some of which were gained during the transition from algae to embryophytes (Manhart and Palmer 1990; Lew and Manhart 1993;Lee and Manhart 2002). Here we examine a gene cluster that, in land plants, contains psbB, psbT, psbH, petB and petD with introns found in petB and petD (petB.i and petD.i). In addition the presence/absence of introns in trnA and trnI (trnA.i and trnI.i) were determined in all five major lineages of charophytes. We found that the psbB gene cluster occurs in most surveyed charophytes and embryophytes except Spirogyra (Zygnematales) which lacks it due to intra-genomic rearrangement. All four introns are absent in Chlorokybus but present in some or all of the other four charophyte lineages (Klebsormidiales, Zygnematales, Coleochaetales, and Charales). In addition, Chlorokybus is distinguished from other charophytes and embryophytes by having an unusually long spacer (over 2 kb) between psbH-petB. The results indicate that Chlorokybus diverged before the intron gains but after psbB gene cluster formation, placing the other charophyte lineages closer to embryophytes.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.17 no.2
• /
• pp.79-85
• /
• 2019

Purpose: The purpose of this study is to evaluate the effectiveness of vitamin B12 treatment in subacute combined degeneration (SCD) caused by nitrous oxide (N₂O) abuse. Methods: Relevant literature was accessed through PubMed, EMBASE, Scopus, and KoreaMed. All the literature that was relevant to human use of vitamin B12 treatment for SCD caused by N₂O abuse was included. Case reports were excluded if the treatment regimens were not precisely described. The literature search was conducted by two investigators during September 2019 for the final publication period. The languages of the publications were restricted to English and Korean. Results: Twenty-three published articles that contained 24 cases were included. Sixteen cases among them were treated with intramuscular vitamin B12 of 1 mg/day and the rest received different doses or routes. Although most cases described significant clinical improvements, one case showed no beneficial effect due to the patient's noncooperation. Another case showed adverse events, including spinal myoclonus, following vitamin B12 therapy. Conclusion: Vitamin B12 has been broadly used for the treatment of SCD caused by N₂O abuse. However, most of the relevant studies were case reports that reported various regimens of vitamin B12 administration. Further studies are needed to establish a standard regimen of vitamin B12 because the incidence of N₂O abuse may increase in South Korea.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.17 no.5
• /
• pp.77-86
• /
• 2013

This study investigates the fundamental properties of the water-binder (W/B) ratio and fine aggregate-binder (F/B) ratio in the alkali-activated slag cement (AASC) mortar. The W/B ratios are 0.35, 0.40, 0.45, and 0.50, respectively. And then the F/B ratios varied between 1.00 and 3.00 at a constant increment of 0.25. The alkali activator was an 2M and 4M NaOH. The measured mechanical properties were compared, flow, compressive strength, absorption, ultra sonic velocity, and dry shrinkage. The flow, compressive strength, absorption, ultra sonic velocity and dry shrinkage decreased with increases W/B ratio. The compressive strength decreases with increase F/B ratio at same W/B ratio. Also, at certain value of F/B ratio significant increase in strength is observed. And S2 (river sand 2) had lower physical properties than S1 (river sand 1) due to the fineness modulus. The results of experiments indicated that the mechanical properties of AASC depended on the W/B ratio and F/B ratio. The optimum range for W/B ratios and F/B ratios of AASC is suggested that the F/B ratios by 1.75~2.50 at each W/B ratios. Moreover, the W/(B+F) ratios between 0.13 and 0.14 had a beneficial effect on the design of AASC mortar.

• Journal of Nutrition and Health
• /
• v.28 no.7
• /
• pp.675-687
• /
• 1995

The purpose of this study were to analyze work patterns of clinical dietitians by time study, to investigate labor time used in each clinical dietetic activity, and to develop standardized indices of clinical dietetic staffing needs. Two general hospitals(A & B) in Seoul were selected for study. The results of this study can be summarized as follows. 1) For the A hospital, the percentage of clinical dietetic activities such as attending meeting, professional research, foodservicemanagement, clerical activity for the foodservice, administrative activity and delay were 17.5%, 1.3%, 14.5%, 23.4%, 21.3%, 4.6%, and 17.3% respectively, while 22.4% 3.5%, 23.7%, 10.9%, 15.8%, 4.2%, and 19.5% respectively for the B hospital. 2) For the A hospital, the percentage of direct patient care like outpatient nutrition education, group nutrition education, and patient meal planning were 69.5%, 10.5%, 7.6%, and 12.4% respectively while 78.9%, 7.3%, 8.9%, and 5.1% respectively for the B hospital. 3) Time spent for performing direct patient care such as basic care, intermediate care, and indepth care per patient were 28.0min, 73.1min, and 53.0 min respectively for the A hospital, while 45.3 min, 76.2 min, and 52.6 min respectively for the B hospital. 4) Full time clinical dietitian staffing needs were calculated for the three parts ; basic care, intermediate care, and in-depth care. For A hspital, the appropriate numbers of full time clinical dietitian were 3.5 persons in basic care, 3.6 persons in intermediate care, and 1.3 persons in in-depth care, while 6.1 persons, 6.3 persons, 3.2 persons respectively for B hospital.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.11
• /
• pp.93-99
• /
• 2012

The B3G networks that provide the internetworking techniques of heterogeneous network systems and services are constructed to support various service requirements of mobile users. In this paper, we represent the internetworking scheme of heterogeneous networks systems such like UMTS and WLAN which can be used as access networks, and illustrate the service providing of each network system and the internetworking service based on heterogeneous access networks. UMTS and WLAN can provide each proper service to mobile users, and is included to B3G networks to increase the service usage effectiveness by using complementary service for mobile users.