• Title/Summary/Keyword: FSE

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Projection-type Fast Spin Echo Imaging (프로젝션 타입 고속 스핀 에코 영상)

  • 김휴정;김치영;김상묵;안창범
    • Investigative Magnetic Resonance Imaging
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    • v.4 no.1
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    • pp.42-51
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    • 2000
  • Purpose: Projection-type Fast Spin Echo (PFSE) imaging is robust to patient motion or flow related artifact compared to conventional Fast Spin Echo (FSE) imaging, however, it has difficulty in controlling $T_2$ contrast. In this paper, Tz contrast in the PFSE method is analyzed and compared with those of the FSE method with various effective echo times by computer simulation. The contrasts in the FSE and PFSE methods are also compared by experiments with volunteers. From the analysis and simulation, it is shown that ${T_2}-weighted$ images can well be obtained by the PFSE method proposed. Materials and methods: Pulse sequence for the PFSE method is implemented at a 1.0 Tesla whole body MRI system and $T_2$ contrasts in the PFSE and FSE methods are analyzed by computer simulation and experiment with volunteers. For the simulation, a mathematical phantom composed of various $T_2$ values is devised and $T_2$ contrast in the reconstructed image by the PFSE is compared to those by the FSE method with various effective echo times. Multi-slice ${T_2}-weighted$ head images of the volunteers obtained by the PFSE method are also shown in comparison with those by the FSE method at a 1.0 Tesla whole body MRI system. Results: From the analysis, $T_2$ contrast by the PFSE method appears similar to those by the FSE method with the effective echo time in a range of SO-lOOms. Using a mathematical phantom, contrast in the PFSE image appears close to that by the FSE method with the effective echo time of 96ms. From experiment with volunteers, multi-slice $T_2-weighted$ images are obtained by the PFSE method having contrast similar to that of the FSE method with the effective echo time of 96ms. Reconstructed images by the PFSE method show less motion related artifact compared to those by the FSE method. Conclusion: The projection-type FSE imaging acquires multiple radial lines with different angles in polar coordinate in k space using multiple spin echoes. The PFSE method is robust to patient motion or flow, however, it has difficulty in controlling $T_2$ contrast compared to the FSE method. In this paper, it is shown that the PFSE method provides good $T_2$ contrast (${T_2}-weighted$ images) similar to the FSE method by both computer simulation and experiments with volunteers.

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Hypoglycemic Effect of Fermented Soymilk Extract in STZ-induced Diabetic Mice

  • Yi, Na-Ri;Hwang, Ji-Young;Han, Ji-Sook
    • Preventive Nutrition and Food Science
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    • v.14 no.1
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    • pp.8-13
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    • 2009
  • This study investigated the hypoglycemic effect of fermented soymilk extract (FSE) in STZ-induced diabetic mice. FSE was prepared via fermentation of soymilk with Bacillus subtilis followed by methanol extraction. The hypoglycemic effect was determined by inhibitory activities against ${\alpha}$-glucosidase and ${\alpha}$-amylase as well as the alleviation of postprandial glucose level. The non-fermented soymilk extract (SE) was used as control in this experiment. FSE showed higher (p<0.05) inhibitory activities than SE against ${\alpha}$-glucosidase and ${\alpha}$-amylase. The $IC_{50}$ values of FSE for ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.77 ancd 0.94 mg/mL, respectively, which were comparable or even superior to those of acarbose (0.79 and 0.68 mg/mL, respectively). In addition, a further suppression on the postprandial blood glucose levels were observed in the FSE than SE group for both STZ-induced diabetic mice and normal mice. Furthermore, FSE significantly lowered the incremental area under the curve (AUC) in the diabetic mice and the AUC in normal mice corroborated the hypoglycemic effect of FSE (p<0.05). Results from this study suggest that FSE may help decrease the postprandial blood glucose level via inhibiting ${\alpha}$-glucosidase and ${\alpha}$-amylase and the usefulness of FSE was proven to be better than SE.

Fixed-complexity Sphere Encoder for Multi-user MIMO Systems (다중 사용자 MIMO 시스템을 위한 고정 복잡도를 갖는 스피어 인코더)

  • Mohaisen, Manar;Han, Dong-Keol;Chang, Kyung-Hi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.7A
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    • pp.632-638
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    • 2010
  • In this paper, we propose a fixed-complexity sphere encoder (FSE) for multi-user MIMO (MU-MIMO) systems. The Proposed FSE accomplishes a scalable tradeoff between performance and complexity. Also, because it has a parallel tree-search structure, the proposed encoder can be easily pipelined, leading to a tremendous reduction in the precoding latency. The complexity of the proposed encoder is also analyzed, and we propose two techniques that reduce it. Simulation and analytical results demonstrate that in a $4\times4$ MU-MIMO system, the complexity of the proposed FSE is 16% that of the conventional QRD-M encoder (QRDM-E). Also, the encoding throughput of the proposed endoder is 7.5 times that of the QRDM-E with tolerable degradation in the BER performance, while achieving the optimum diversity order.

The Effectiveness of 3D FIESTA (Three Dimensional Fast Imaging Employing Steady-state Acquisition) MRI in Sudden Hearing Loss Patients (돌발성 난청 환자에서 3D FIESTA (three dimensional fast imaging employing steady-state acquisition) MRI의 유용성)

  • Cho, Jae-Hwan;Kim, Hyun-Ju;Park, Cheol-Soo
    • Journal of Digital Contents Society
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    • v.11 no.4
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    • pp.425-431
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    • 2010
  • This study explored the effects and the effectiveness of the new method of 3D FIESTA by making quantitative comparison with the conventional 3D FSE method which is frequently employed on patients with sudden hearing loss in clinical settings. For this study, 3D FSE images acquired with 3.0T MR scanner and T2-weighted axial plane 3D FIESTA images were respectively taken from 40 patients diagnosed with Sensorineural Hearing Loss (SSHL). When obtaining those images, sagittal reconstructions oriented perpendicular to the nerve were performed in order to get sagittal images of both right and left internal auditory canal. The findings showed that both SNR and CNR were higher among the group to whom the 3D FIESTA method was applied than the group to whom the conventional 3D FSE method was applied.

Comparison of Contrast-Enhanced T2 FLAIR and 3D T1 Black-Blood Fast Spin-Echo for Detection of Leptomeningeal Metastases

  • Park, Yae Won;Ahn, Sung Jun
    • Investigative Magnetic Resonance Imaging
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    • v.22 no.2
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    • pp.86-93
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    • 2018
  • Purpose: Imaging plays a significant role in diagnosing leptomeningeal metastases. However, the most appropriate sequence for the detection of leptomeningeal metastases has yet to be determined. This study compares the efficacies of contrast-enhanced T2 fluid attenuated inversion recovery (FLAIR) and contrast-enhanced 3D T1 black-blood fast spin echo (FSE) imaging for the detection of leptomeningeal metastases. Materials and Methods: Tube phantoms containing varying concentrations of gadobutrol solution were scanned using T2 FLAIR and 3D T1 black-blood FSE. Additionally, 30 patients with leptomeningeal metastases were retrospectively evaluated to compare conspicuous lesions and the extent of leptomeningeal metastases detected by T2 FLAIR and 3D T1 black-blood FSE. Results: The signal intensities of low-concentration gadobutrol solutions (< 0.5 mmol/L) on T2 FLAIR images were higher than in 3D T1 black-blood FSE. The T2 FLAIR sequences exhibited significantly greater visual conspicuity scores than the 3D T1 black-blood sequence in leptomeningeal metastases of the pial membrane of cistern (P = 0.014). T2 FLAIR images exhibited a greater or equal extent (96.7%) of leptomeningeal metastases than 3D T1 black-blood FSE images. Conclusion: Because of its high sensitivity even at low gadolinium concentrations, contrast-enhanced T2 FLAIR images delineated leptomeningeal metastases in a wider territory than 3D T1 black-blood FSE.

Anti-oxidant effect of forsythia suspensa on cellular damage in the chronic disease (연교의 항산화 효과 연구)

  • Young-Eun Kim;Min-Jin Kim;Su-Jin Bae;Seon Been Bak;Sun-Dong Park;Kwang-Il Park;Young Woo Kim
    • Herbal Formula Science
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    • v.32 no.1
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    • pp.51-61
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    • 2024
  • Objectives : This study induced oxidative stress in HepG2 cells by treating them with AA+iron and investigated the effects of forsythia suspensa extract on this stress, as well as elucidated the molecular mechanisms underlying its hepatoprotective effects. Methods : To confirm the antioxidative effects of FSE, HepG2 cells were induced with AA+iron to induce oxidative stress, followed by MTT assay. Additionally, the effect of FSE in reducing the increased ROS levels and mitochondrial damage induced by AA+iron in HepG2 cells was confirmed using FACS. Furthermore, western blot analysis were conducted to investigate the molecular mechanisms underlying the hepatoprotective effects of FSE. Results : FSE increased the decreased cell viability induced by AA+iron. Additionally, FSE normalized the expression of apoptosis-related proteins induced by AA+iron. The elevated ROS levels in HepG2 cells induced by AA+iron were reduced by FSE, and the increase in Rh123-negative cells induced by AA+iron was attenuated by FSE. Moreover, FSE activated the protein expression of AMPK and its related phosphorylating enzymes, LKB1 and ACC. Furthermore, FSE activated YAP and its upstream phosphorylating enzyme, LATS1. Conclusions : These results demonstrate that FSE has an inhibitory effect on oxidative stress induced by AA+iron and may have potential hepatoprotective effects.

Antioxidative effects of fermented sesame sauce against hydrogen peroxide-induced oxidative damage in LLC-PK1 porcine renal tubule cells

  • Song, Jia-Le;Choi, Jung-Ho;Seo, Jae-Hoon;Kil, Jeung-Ha;Park, Kun-Young
    • Nutrition Research and Practice
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    • v.8 no.2
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    • pp.138-145
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    • 2014
  • BACKGROUND/OBJECTIVES: This study was performed to investigate the in vitro antioxidant and cytoprotective effects of fermented sesame sauce (FSeS) against hydrogen peroxide ($H_2O_2$)-induced oxidative damage in renal proximal tubule LLC-PK1 cells. MATERIALS/METHODS: 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical ($^{\bullet}OH$), and $H_2O_2$ scavenging assay was used to evaluate the in vitro antioxidant activity of FSeS. To investigate the cytoprotective effect of FSeS against $H_2O_2$-induced oxidative damage in LLC-PK1 cells, the cellular levels of reactive oxygen species (ROS), lipid peroxidation, and endogenous antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px) were measured. RESULTS: The ability of FSeS to scavenge DPPH, $^{\bullet}OH$ and $H_2O_2$ was greater than that of FSS and AHSS. FSeS also significantly inhibited $H_2O_2$-induced ($500{\mu}M$) oxidative damage in the LLC-PK1 cells compared to FSS and AHSS (P < 0.05). Following treatment with $100{\mu}g/mL$ of FSeS and FSS to prevent $H_2O_2$-induced oxidation, cell viability increased from 56.7% (control) to 83.7% and 75.6%, respectively. However, AHSS was not able to reduce $H_2O_2$-induced cell damage (viability of the AHSS-treated cells was 54.6%). FSeS more effectively suppressed $H_2O_2$-induced ROS generation and lipid peroxidation compared to FSS and AHSS (P < 0.05). Compared to the other sauces, FSeS also significantly increased cellular CAT, SOD, and GSH-px activities and mRNA expression (P < 0.05). CONCULUSIONS: These results from the present study suggest that FSeS is an effective radical scavenger and protects against $H_2O_2$-induced oxidative damage in LLC-PK1 cells by reducing ROS levels, inhibiting lipid peroxidation, and stimulating antioxidant enzyme activity.

Protective Effects of Fermented Soymilk Extract on High Glucose-Induced Oxidative Stress in Human Umbilical Vein Endothelial Cells

  • Yi, Na-Ri;Park, Min-Jung;Han, Ji-Sook
    • Preventive Nutrition and Food Science
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    • v.15 no.1
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    • pp.7-13
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    • 2010
  • We investigated whether the fermented soymilk extract (FSE) has protective effects against high glucose-induced oxidative stress in human umbilical vein endothelial cells (HUVECs). FSE was prepared via fermentation of soymilk with Bacillus subtilis followed by methanol extraction. To determine the protective effect of FSE, oxidative stress was induced by exposing of HUVECs to the high glucose (30 mM) for 48 hr. Exposure of HUVECs to high glucose for 48 hr resulted in a significant (p<0.05) decrease in cell viability, catalase, SOD and GSH-px activity and a significant (p<0.05) increase in intracellular ROS level and thiobarbituric acid reactive substances (TBARS) formation in comparison to the cells treated with 5.5 mM glucose. However, at concentration of 0.1 mg/mL, FSE treatment decreased intracellular ROS level and TBARS formation, and increased cell viability and activities of antioxidant enzymes including catalase, SOD and GSH-px in high glucose pretreated HUVEC. These results suggest that FSE may be able to protect HUVECs from high glucose-induced oxidative stress, partially through the antioxidative defense systems.

A Review on Fire Safety Engineering: Key Issues for High-Rise Buildings

  • Li, Guo-Qiang;Zhang, Chao;Jiang, Jian
    • International Journal of High-Rise Buildings
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    • v.7 no.4
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    • pp.265-285
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    • 2018
  • This paper presents a state-of-the-art review on the design, research and education aspects of fire safety engineering (FSE) with a particular concern on high-rise buildings. FSE finds its root after Great Fire of Rome in 64 AD, followed by Great London Fire in 1666. The development of modern FSE is continuously driven by industry revolution, insurance community and government regulations. Now FSE has become a unique engineering discipline and is moving towards performance-based design since 1990s. The performance-based fire safety design (PBFSD) involves identification of fire safety goals, design objectives, establishment of performance criteria, and selection of proper solutions for fire safety. The determination of fire scenarios and design fires have now become major contents for PBFSD. To experience a rapid and positive evolution in design and research consistent with other engineering disciplines, it is important for fire safety engineering as a profession to set up a special educational system to deliver the next-generation fire safety engineers. High-rise buildings have their unique fire safety issues such as rapid fire and smoke spread, extended evacuation time, longer fire duration, mixed occupancies, etc., bringing more difficulties in ensuring life safety and protection of property and environment. A list of recommendations is proposed to improve the fire safety of high-rise buildings. In addition, some source information for specific knowledge and information on FSE is provided in Appendix.

Inhibitory Effect of Fermented Spanish Extract on Inorganic phosphate-induced Vascular Calcification in ex vivo Aortic Rings (발효 시금치 추출물의 무기인산염에 의해 유도된 혈관 석회화 저해 효과)

  • Lee, Sang Hee;Hong, Sun Mi;Sung, Mi Jeong
    • Journal of the Korean Society of Food Culture
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    • v.37 no.3
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    • pp.248-255
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    • 2022
  • Spinach (Spinacia oleracea L.), a green leafy vegetable, is well known as a functional food due to its biological activities. Vascular calcification is associated with several disease conditions including atherosclerosis, diabetes, and chronic kidney disease (CKD), and is known to raise the risk of cardiovascular diseases related morbidity and mortality. However, there are no previous studies that have investigated the effects of fermented spinach exract (FSE) against aortic and its underlying mechanisms. Therefore, this study investigated the effects and action of possible mechanisms of FSE on inorganic phosphate (PI)-induced vascular calcification in ex vivo mouse aortic rings. PI increased vascular calcification through calcium deposition in ex vivo aortic rings. FSE inhibited calcium accumulation and osteogenic key marker, runt-related transcription factor 2 (Runx2), and bone Morphogenetic Protein 2 (BMP-2) protein expression in ex vivo aortic rings. And, FSE inhibited PI-induced extracellular signal-regulated kinase (ERK) and p38 phosphorylation in ex vivo aortic rings. These results show that FSE can prevent vascular calcification which may be a crucial way for the prevention and treatment of vascular disease association with vascular calcification.