• Preventive Nutrition and Food Science
• /
• v.13 no.1
• /
• pp.54-59
• /
• 2008

This study was conducted to investigate the effect of pH on the formation of furfural compounds from glucose and fructose reacting with amino acid enantiomers in the Maillard reaction. Hydroxymethylfurfural (HMF) content was highest at pH 4.0, and decreased with increasing pH. HMF was significantly higher in glucose-based systems than fructose-based systems. Furfuryl alcohol (FFA) and 5-methyl-2-furaldehyde (MF) were not increased with increasing pH, and only small amounts were formed. In addition, 2-furaldehyde (F) was found to increase in the systems, as pH increased. However, the content was small and variable. 2,5-Dimethyl-4-hydroxy-3(2H)-furanone (DMHF) was only found in Glc/D-Asn, Glc/L-Lys and Fru/D-Lys system, but the content was not increased with increasing pH. 2-acetylfuran (AF) was higher in Glc (or Fru)/L-Lys and Glc (or Fru)/D-Lys systems at pH 7.0. However, at pH 4.0, the content of AF was higher in the Glc (or Fru)/Gly and Glc (or Fru)/L-Asn systems. Therefore, this study aimed to observe the effect of pH, sugars and amino acid enantiomers on the production of furfural and related compounds by the Maillard reaction. A clear tendency was observed for some classes of compounds to be more easily formed at higher or lower pH. HMF was more readily formed at lower pH, while FFA, F, DMHF and MF were inhibited by acidic conditions. Particularly, compounds like FFA, F and MF were not affected by pH changes. In addition, DMHF and MF were only formed in L-Lys and D-Lys system.

• Journal of the Korean Magnetics Society
• /
• v.13 no.2
• /
• pp.59-63
• /
• 2003

Superparamagnetic properties of self-aggregated cobalt nanoparticles in the perfluorinated ion-exchange polymeric membrane (MF-4SK) prepared by ion-exchange and recovery methods were investigated by transmission electron microscopy (TEM) and superconducting quantum interference device (SQUID) magnetometer at various temperatures. Our experimental results show that cobalt nanoparticles in MF-4SK for the concentration of $7.8{\times}10^{19}$ atoms per 1 g of polymer membrane exhibit superparamagnetic properties above the average blocking temperature ($T_{B}$), which is determined to be around 185 K at applied field of 500 Oe. The average particle radius of 4.0 nm achieved from Langevin function fit is in good agreement with TEM observations. This experimental evidence suggests that cobalt nanoparticles in polymer film obey a single domain theory. The results are discussed in the light of current theory for the superparamagnetic behavior of magnetic nanoparticles.

• Journal of Animal Science and Technology
• /
• v.54 no.2
• /
• pp.95-101
• /
• 2012

The objective of this study was to examine the effect of amides as a cryoprotectant for semen cryopreservation in Korean Jeju Black Bull. The semen was cryopreserved with extenders containing 5% dimethyl acetamide (DMA), 5% dimethyl formamide (DMF), 5% methyl formamide (MF) or 7% glycerol. Post-thawed sperm were evaluated for sperm motility, viability, acrosome integrity and membrane integrity. Post-thawed sperm motility was significantly higher (p<0.05) in glycerol and DMF ($64.00%{\pm}9.62$ and $59.00%{\pm}5.48$, respectively) than DMA and MF ($50.00%{\pm}3.24$ and $44.00%{\pm}4.18$, respectively). Sperm viability wassignificantly higher (p<0.05) in glycerol and DMF ($58.25%{\pm}7.35$ and $53.05%{\pm}3.77$, respectively) than others. However, for sperm motility and viability, there were no differences among glycerol and DMF. Also, swelling sperm ratio by hypo-osmetic selling test (HOST) was significantly increased (p<0.05) in glycerol and DMF treatments ($45.12%{\pm}25.08$ and $44.95%{\pm}8.58$, respectively). The percentage of capacitated sperm assessed by CTC staining, F pattern was lower (p<0.05) in DMF than others. B pattern was increased (p<0.05) in DMA, DMF and MF when compared with glycerol. AR pattern ratio was decreased (p<0.05) in glycerol and DMF when compared with DMA and MF. These results suggested that amides performed better and could be used as a cryoprotectant for semen freezing of Korean Jeju Black Bull.

• Physical Therapy Korea
• /
• v.20 no.1
• /
• pp.1-9
• /
• 2013

The purpose of this study was to determine the effect of the pelvic compression belt (PCB) on the electromyography (EMG) activities of trunk muscles during sit-to-stand (SitTS), and stand-to-sit (StandTS) tasks. Twenty healthy subjects (7 men and 13 women) were recruited for this study. The subjects performed SitTS, and StandTS tasks, with and without a PCB. Surface EMG was used to record activity of the internal oblique (IO), external oblique (EO), rectus abdominis (RA), erector spinae (ES), and multifidus (MF) of the dominant limb. EMG activity significantly decreased in the RA (without the PCB, $8.34{\pm}6.04$ %maximal voluntary isometric contraction [%MVIC]; with the PCB, $7.64{\pm}5.11$ %MVIC), EO (without the PCB, $14.83{\pm}11.82$ %MVIC; with the PCB, $11.98{\pm}7.60$ %MVIC), MF (without the PCB, $21.74{\pm}7.76$ %MVIC; with the PCB, $18.50{\pm}8.04$ %MVIC), and ES (without the PCB, $18.39{\pm}7.16$ %MVIC; with the PCB, $16.63{\pm}6.31$ %MVIC) during the SitTS task and in the IO (without the PCB, $20.58{\pm}15.60$ %MVIC; with the PCB, $17.27{\pm}12.32$ %MVIlC), RA (without the PCB, $8.04{\pm}5.68$ %MVIC; with the PCB, $7.40{\pm}4.71$ %MVIC), EO (without the PCB, $13.29{\pm}8.80$ %MVIC; with the PCB, $11.24{\pm}6.14$ %MVIC), MF (without the PCB, $18.59{\pm}7.64$ %MVIC; with the PCB, $15.86{\pm}6.48$ %MVIC), and ES (without the PCB, $17.14{\pm}6.44$ %MVIC; with the PCB, $15.46{\pm}5.62$ %MVIC) during the StandTS task when a PCB was used (p<.05). In men the EMG activity of the MF significantly decreased during the SitTS task when a PCB was used (p<.05): in women, the EMG activity of the RA, EO, MF, and ES during the SitTS task and that of the EO, MF, and ES during the SitTS task significantly decreased when a PCB was used (p<.05). In addition, the rates of change in the EMG activity of each muscle differed significantly during the SitTS and StandTS tasks before and after the use of the PCB. However, the EMG activity did not significantly differ between the male and female subjects. These findings suggest that the PCB may contribute to the modification of activation patterns of the trunk muscles during SitTS, and StandTS tasks.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1996.04a
• /
• pp.58-59
• /
• 1996

기체 막분리 공정은 상업적으로 많은 개발의 여지를 가지고 있지만 RO, UF, MF 등과 같은 수처리분야 정도로 공정의 개발 및 실제 응용분야는 매우 미약한 형편이다. 이와 같은 현실에서 최근 청정 에너지로 각광을 받고 있으며 화학공정의 주원료로 잠재적인 수요를 가지고 있는 수소 기체와 지구 온난화 물질 중 가장 대표적인 물질로 주목받고 있는 이산화탄소의 분리를 목적으로 공정 개발의 타당성 연구를 전산모사를 통해서 수행하였다. 본 전산모사의 목적은 공정 형태별 최적의 공정조건 선정을 위한 타당성 연구를 목적으로 하고 있다.

• The Bulletin of The Korean Astronomical Society
• /
• v.45 no.1
• /
• pp.58.4-59
• /
• 2020

We present preliminary results of 1.1 and 1.3 mm dust continuum and 12CO (J=2-1) line data obtained with the Submillimeter Array toward six cores harboring Class 0/I objects in the λ Orionis cloud. They are located in bright rimmed clouds, which are exposed to the far-ultraviolet radiation field by the O-type star λ Ori. Compact dust continuum emission is observed from all six cores. Among the six cores, only one core G196.92-10.37 shows a signature of binarity with separation of 4000 AU. The numbers of singles and binaries in our sample are five and one, respectively and the derived multiplicity frequency (MF) is 0.17. This value is lower than those found in the binary surveys toward Class 0/I objects, which may be a hint for negative feedback by the nearby massive star, lambda Ori. The derived excitation temperature (Tex) using 12CO emission shows a lower median value (20 K) than those of triggered star-forming regions (30 K). The lower MF and Tex support our previous study that star formation was not triggered in the λ Orionis cloud. We aim to further investigate whether the Class 0/I YSOs in the λ Orionis cloud have less circumstellar materials and smaller accretion rates than in other filamentary clouds (e.g., Orion A & B), which might be attributed to negative feedback from the massive star in limiting accretion of protostars.

• Journal of Korean Neurosurgical Society
• /
• v.59 no.3
• /
• pp.276-281
• /
• 2016

Objective : Although trunk muscles in the lumbar spine preserve spinal stability and motility, little is known about the relationship between trunk muscles and spinal fusion rate. The aim of the present study is to evaluate the correlation between trunk muscles cross sectional area (MCSA) and fusion rate after posterior lumbar interbody fusion (PLIF) using stand-alone cages. Methods : A total of 89 adult patients with degenerative lumbar disease who were performed PLIF using stand-alone cages at L4-5 were included in this study. The cross-sectional area of the psoas major (PS), erector spinae (ES), and multifidus (MF) muscles were quantitatively evaluated by preoperative lumbar magnetic resonance imaging at the L3-4, L4-5, and L5-S1 segments, and bone union was evaluated by dynamic lumbar X-rays. Results : Of the 89 patients, 68 had bone union and 21 did not. The MCSAs at all segments in both groups were significantly different (p<0.05) for the PS muscle, those at L3-4 and L4-5 segments between groups were significantly different (p=0.048, 0.021) for the ES and MF muscles. In the multivariate analysis, differences in the PS MCSA at the L4-5 and L5-S1 segments remained significant (p=0.048, 0.043 and odds ratio=1.098, 1.169). In comparison analysis between male and female patients, most MCSAs of male patients were larger than female's. Fusion rates of male patients (80.7%) were higher than female's (68.8%), too. Conclusion : For PLIF surgery, PS muscle function appears to be an important factor for bone union and preventing back muscle injury is essential for better fusion rate.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 1999.07a
• /
• pp.173-186
• /
• 1999

Several epidemiological studies have suggested that residential or occupational exposure to power frequency magnetic fields (MF) might increase the risk of cancer. The objective of this study is to elucidate the possible carcinogenic effects of MF exposure using female Sprague-Dawley (Crj:CD)rats. A total of 360rats was randomly divided into 6 groups of 60 rats each. Two groups were served as a negative control (vehicle: sesame oil only) or a positive control (single oral administration of 7, 12dimethylbenz(a)anthracene; DMBA, 90mg/kg body weight at 50-52days of age). Other four groups were simultaneously exposed to 0 (sham-exposed) 7, 70 or 350 $\mu$T(rms), continuous circularly polarized 50HzMF, 22 hrs/day, 7 days/weeks for 30weeks from 8weeks of age. Experiment was conducted under SPF condition and in a blinded manner, Ten animals in each grout were served as satellite animals and their several hormonal concentrations in sera, such as melatonin and prolactin, collected at the midnight were measured. In addition, complete histopathological examination were performed in other 50 animals per each group. In the positive control group, the first mammary nodule was palpated at the 7th weeks of experiment in 5 out of 59 animals. Afterward, the incidence of palpable mammary nodules increased steadily and reached at 76% and 98% of live animals at 14weeks and the end of experiment in sham and 350$\mu$ T-exposed groups were not significantly different from those in the sham-exposed and negative control groups. Histopathologocally, most of palpable nodules were mammary tumors. The incidences of animals with mammary tumors per animals survived ant the end of experiment were 4.1 and 100% in the negative and positive control groups, and 0.0, 6.0, 8.0 and 6.0% in the sham-, 7, 70and 350 $\mu$T-exposed groups, respectively. These incidences in three MF-exposed groups were not significantly different from those in both the sham- exposed and negative control groups. Based on these results, it was not supported that continuous circularly polarized 50 Hz magnetic fields at up to 350$\mu$T affect the incidence of spontaneous mammary tumors in female SD rats under the present experimental conditions.

• Parasites, Hosts and Diseases
• /
• v.59 no.1
• /
• pp.67-76
• /
• 2021

Legionella pneumophila is an opportunistic pathogen that survives and proliferates within protists such as Acanthamoeba spp. in environment. However, intracellular pathogenic endosymbiosis and its implications within Acanthamoeba spp. remain poorly understood. In this study, RNA sequencing analysis was used to investigate transcriptional changes in A. castellanii in response to L. pneumophila infection. Based on RNA sequencing data, we identified 1,211 upregulated genes and 1,131 downregulated genes in A. castellanii infected with L. pneumophila for 12 hr. After 24 hr, 1,321 upregulated genes and 1,379 downregulated genes were identified. Gene ontology (GO) analysis revealed that L. pneumophila endosymbiosis enhanced hydrolase activity, catalytic activity, and DNA binding while reducing oxidoreductase activity in the molecular function (MF) domain. In particular, multiple genes associated with the GO term 'integral component of membrane' were downregulated during endosymbiosis. The endosymbiont also induced differential expression of various methyltransferases and acetyltransferases in A. castellanii. Findings herein are may significantly contribute to understanding endosymbiosis of L. pneumophila within A. castellanii.

• Journal of Preventive Medicine and Public Health
• /
• v.23 no.3 s.31
• /
• pp.296-308
• /
• 1990

The relationship between copper and mercury contents in the scalp hair and chronic schizophrenia was investigated. The samples of scalp hair were collected from 80 male chronic schizophrenic patients at the age from 20 to 29, who were hospitalized in the National Psychiatric Hospital in Seoul. As the control group, 69 males were collected from general population. Hair samples were taken from the napes and the Minnesota Multiple Personality Inventory (MMPI) was performed also. The copper and mercury contents were determined by an atomic absorption spectrophotometer. Significantly higher T-score of MMPI was seen in patients group for Hypochondriasis Scale (Hs), Depression Scale (D), Psychopathic Deviate Scale (Pd), Paranoia Scale (Pa), Psychasthenia Scale (Pt), Schizophrenia Scale (Sc) subscales than control group, and the frequency distribution by T-score was also significantly different between the patient and the control group for above scales. The content of copper in the hair of patient group was significantly lower than the control group. In the case of mercury, the mean value of patient group was significantly higher than control group. Between the value of copper and mercury, statistically significant negative correlation (r=-0.25) was found. When grouped by the T-score of MMPI, there was no difference of copper contents between T-score subgroup at all MMPI scale. But the mercury contents showed significant difference between T-score subgroup at Pt, Sc scale. When compared between the group of above 70 T-score and the group of less than 70, the mercury contents of Pa, Pt, Sc scale of above 70 T-score group were significantly higher than the group of less than 70. In other scales, the mercury content of the above 70 group were higher than the group of less than 70 except Mf scale, although there were no statistscally significances. In D, Pa, Sc scales, as the T-score of MMPI increased, the contents of mercury also increased. When divided into the patient group and the control group, the copper contents of the patient groups were significantly lower than the control group at each T-score scale in most MMPI scales. In the case of mercury, the value of patient group were significantly higher than the control group in the less than 44 scale of D, in the $60{\sim}69$ scale of Pd, in the $45{\sim}59$ scale of Mf, in the $60{\sim}69$ scale of Ma, in the less than 44 of Si. These results suggest that the effects of the deficiency of copper or high intake of mecury on schizophrenia and personality may be of possible value. Thus further studies are necessary to determine whether schizophrenia and personality formation would be attributed to copper deficiency or mercury intake.