• Journal of the Optical Society of Korea
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• 제7권2호
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• pp.84-88
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• 2003

A new method for temperature compensation of fiber Bragg grating (FBG) using hi-metal is proposed and experimentally demonstrated. Bi-metal bends toward the metal of low temperature expansion coefficient as the temperature increases, and this property is utilized to cancel the thermo-optic effect of the fiber. The optimum thickness of the high coefficient metal was empirically found by the trial-and-error method. The temperature sensitivities were 8.1 pm/$^{\circ}C$ and -0.018 pm/$^{\circ}C$ for the uncompensated and compensated FBGs, respectively, which indicates a reduction to a mere 0.22 % of the original sensitivity. No appreciable change in the spectral shape was observed. The packaging technique described in this paper is simple and compact, and it can be used for FBGs in WDM and DWDM communication systems that have stringent requirements on the temperature stability of the components.

• 한국산학기술학회논문지
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• 제17권2호
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• pp.627-634
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• 2016

본 연구는 일부 종합검진 수검자들을 대상으로 비만수준이 혈 중 uric acid에 미치는 영향을 검토하고자 2011년 1월부터 12월까지 광주광역시의 일개 종합병원 건강검진센터에서 종합건강검진을 받았던 20세 이상의 지역주민 1,118명(남자 636, 여자 482)을 분석대상으로 하였다. 우리는 혈청 uric acid, 요소 질소, creatinine 뿐만 아니라 신체계측 (SBP, DBP 및 BMI)에 대해 평가하고, 분석에 포함 하였다. Model I에서, 연령, 성별, SBP, DBP, TC, TG, HDL-C, FBG를 보정하였을 때, 남성(p<0.001)과 여성(p=0.036)에서 uric acid의 평균값은 비만수준이 증가할수록 증가하였다. Model II에서, BUN과 creatinine을 추가로 보정하였을 때, 남성에서는 uric acid의 평균값이 정상 체중군은 $4.89{\pm}0.07mg/dl$, 과체중군은 $5.01{\pm}0.09mg/dl$, 비만군은 $5.35{\pm}0.08mg/dl$로 비만수준이 증가할수록 증가하였다(p<0.001). 그러나 여성에서는 uric acid의 평균값이 정상체중군은 $5.03{\pm}0.08mg/dl$, 과체중군은 $5.19{\pm}0.11mg/dl$, 비만군은 $5.27{\pm}0.09mg/dl$로 유의한 차이가 없었다(p=0.191). 결론적으로, 남성에서 비만수준의 증가는 혈 중 uric acid의 증가와 관련이 있지만, 여성에서는 관련이 없었다.

• Molecular & Cellular Toxicology
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• 제4권4호
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• pp.348-354
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• 2008

Bisphenol A (BPA), an environmental endocrine disrupter, enters the human body continuously in food and drink. Young children are likely to be more vulnerable than adults to chemical exposure due to the immaturities of their organ systems, rapid physical development, and higher ventilation, metabolic rates, and activity levels. The direct effect of BPA on peripheral tissue might also be of importance to the development of insulin resistance. However, the influence that BPA has on insulin signaling molecules in skeletal muscle has not been previously investigated. In this study, we examined the effect of BPA on fasting blood glucose (FBG) in post-weaned Wistar rats and on insulin signaling proteins in C2C12 skeletal muscle cells. Subsequently, we investigated the effects of BPA on insulin-mediated Akt phosphorylation in C2C12 myotubes. In rats, BPA treatment (0.1-1,000 ng/mL for 24 hours) resulted in the increase of FBG and plasma insulin levels, and reduced insulin-mediated Akt phosphorylation. Furthermore, the mRNA expression of insulin receptor (IR) was decreased after 24 hours of BPA treatment in C2C12 cells in a dose-dependent manner, whereas the mRNA levels of other insulin signaling proteins, including insulin receptor substrate-1 (IRS-1) and 5'-AMP-dependent protein kinase (AMPK), were unaffected. Treatment with BPA increased GLUT4 expression and protein tyrosine phosphatase 1B (PTP1B) activity in C2C12 myotubes, but not in protein levels. We conclude that exposure to BPA can induce insulin resistance by decreasing IR gene expression, which is followed by a decrease in insulin- mediated Akt activation and increased PTP1B activity.

• KSBB Journal
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• 제18권4호
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• pp.335-339
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• 2003

전반적인 유효율은 1차 유효성 평가항목인 당화혈색소가 0주 평균 7.0$\pm$1.1%에서 8주간 인슈몬 투여후 6.7$\pm$0.9%로 유의하게 감소하였으며 (p=0.0202), 특히 혈당 조절이 잘 되지 않는 당화혈색소 7.0% 초과(기저치)군에서도 0주 평균 8.1$\pm$0.8%에서 4주 투여후 7.7$\pm$0.7%로, 8주 투여 후 7.5$\pm$0.8%로 유의하게 감소하였다(p=0.0171). 당화혈색소 7%이하인 군에서도 유의차는 보이지 않으나 0주 평균 6.2$\pm$0.3%에서 8주 투여 후 6.2$\pm$0.6%로 다소 감소하여 당화혈색소가 7% 이하로 잘 유지되고 있음을 보여주었다. 본 연구를 통하여 당뇨병 관리를 목적으로 의약품이 아닌 기능성 식품의 대체요법에 대한 평가가 이루어진 전례가 거의 없는 상황에서 천연식물 추출물을 주원료로 한 기능성 식품인 인슈몬의 유효성과 안전성을 평가함으로써 제2형 당뇨병 개선에 많은 도움이 되리라 사료된다.

• 한방비만학회지
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• 제20권2호
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• pp.69-77
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• 2020

Objectives: In this study, we investigated the antiobesity and antidiabetic effects of polyherbal extract, DM2 consisting of Atractylodis Rhizoma, Anemarrhenae Rhizoma, Cinnamomi Cortex, and Moutan Radicles Cortex in high fat diet-induced obesity mice. Methods: DM2 extract was prepared with a hot water. Six-week-old male C57BL/6N mice were fed a high-fat diet (HFD) for 8 weeks and then administrated with DM2 extract (500 mg/kg, p.o.) for 4 weeks. The changes of physiological markers, body weight (BW), food and water intakes, and the levels of fasting blood glucose (FBG) were measured once a week for 4 weeks in mice. The the serum levels of glucose, insulin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol (T-CHO), triglyceride, and low density lipoprotein cholesterol in sera were measured in mice using autometic chemical analyzer and enzyme linked immunosorbant assay. We also observed the histological changes of liver and pancreatic tissues with Hematoxylin & Eosin staining. Results: In physiological change, the increases of BW, calorie intake, and FBG in HFD-induced obese mice were significantly decreased after administration of DM2 extract for 4 weeks. The decrease of water intake was significantly increased in DM2 extract-administrated mice. In serological change, the administration of DM2 extract in obesity mice was significantly decreased the serum levels of glucose, insulin, T-CHO, AST, and ALT levels. We also found that DM2 extract inhibited the increase of lipid droplets in liver and the structural destruction of pancreatic tissues in obesity mice. Conclusion: Our study demonstrated that DM2 extract has antiobesity antidiabetic effects with body weight loss, decrease of glucose and insulin levels, and lipid accumulation on liver tissue.

• 대한본초학회지
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• 제37권1호
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• pp.1-9
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• 2022

Objective : This study was designed to investigate anti-diabetic effects of fermented soy bean extract with herbal medicines (Godjang) in diabetic rat models induced by streptozotocin (STZ) injection. Method : Changes in body weight, drinking water, and food intake were observed for 4 weeks before and after induction of diabetes mellitus in rats. The anti-diabetic capacity of Godjang was analyzed by fasting blood glucose (FBG) every week. Also, after 4 weeks of administration, the oral glucose tolerance test (OGTT) was performed, and then blood levels of insulin were checked. And serum levels of total cholesterol and triglycerides were determined. Histomorphological changes of liver, kidney and pancreatic tissues were also observed in STZ-induced diabetic rats and Godjang administered rats. Result : In Godjang administered group, body weight and water intake were more lower than that of STZ-induced diabetic rats. FBG was decreased in the Godjang administered group than STZ-induced diabetic group. According to OGTT, blood glucose levels at 30 minutes and 60 minutes significantly decreased in Godjang administered group than in STZ-induced diabetic control group. Administration of Godjang extract for 4W significantly decreased levels of serum glucose, total cholesterol (TC), triglycerides (TG) in diabetic rats. In histomorphological analysis of kidney, liver, Godjang administrated groups showed the inhibition of pathological damage. Conclusion : These results suggest that Godjang extract has an anti-diabetic action through decrease in serum glucose, TC, TG levels and recovery of the morphological changes in kidney and liver in STZ-induced diabetic rats.

• 한방비만학회지
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• 제22권2호
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• pp.102-114
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• 2022

Objectives: We investigated the effects of Allii Fistulosi Bulbus (AFB) on high fat diet (HFD)-induced obesity in mice and the regulation of energy metabolism in muscle tissues of mice. Methods: The C57BL/6 mice (6 weeks, male) were fed a HFD for 8 weeks and then administrated with AFB extract at 500 mg/kg (p.o.) once daily for 4 weeks. The body weight (BW), muscle weight, calorie intake, fasting blood glucose (FBG) and serum glucose, insulin, and low-density lipoprotein-cholesterol (LDL-C) levels were measured in mice. It was also observed the histological changes of pancreas, liver, and fat tissues with hematoxylin and eosin staining. It was investigated the phosphorylation of insulin receptor substrate 1 (IRS-1), Ser/Thr kinase (AKT), and adenosine monophosphate-activated protein kinase (AMPK), and the expression of phosphoinositide 3-kinase, glucose transporter type 4 (GLUT4), and sirtuin1 (Sirt1) in gastrocnemius tissues by western blot, respectively. Results: The increases of BWs, calorie intakes and FBG levels in obesity mice were decreased significantly by the administration of AFB extract. The AFB extract administration was reduced significantly serum levels of glucose, insulin, and LDL-C in obesity mice. The AFB extract inhibited lipid accumulation in liver tissues, hyperplasia of pancreatic islets, and enlargement of fat tissues in obesity mice. The phosphorylation of IRS-1 and AKT was increased significantly in muscle tissues and AMPK phosphorylation and the GLUT4 and Sirt1 expression were decreased significantly in muscle tissues after the AFB administration. Conclusions: Our study indicates that AFB extract improves symptoms of obesity through regulation of energy regulating proteins in muscle tissues.

• Nutrition Research and Practice
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• 제17권2호
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• pp.241-256
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• 2023

BACKGROUND/OBJECTIVES: Diabetes-specific oral nutritional supplements (ONS) have anti-hyperglycemic effects, while D-allulose exerts anti-diabetic and anti-obesity effects. In this study, we investigated the efficacy and safety of diabetes-specific ONS, including allulose, on glycemic and weight changes in overweight or obese patients with type 2 diabetes mellitus (T2DM). SUBJECTS/METHODS: A single-arm, historical-control pilot clinical trial was conducted on 26 overweight or obese patients with T2DM (age range: 30-70 yrs). The participants were administered 2 packs of diabetes-specific ONS, including allulose (200 kcal/200 mL), every morning for 8 weeks. The glycemic profiles, obesity-related parameters, and lipid profiles were assessed to evaluate the efficacy of ONS. RESULTS: After 8 weeks, fasting blood glucose (FBG) level significantly decreased from 139.00 ± 29.66 mg/dL to 126.08 ± 32.00 mg/dL (P = 0.007) and glycosylated hemoglobin (HbA1c) improved (7.23 ± 0.82% vs. 7.03 ± 0.69%, P = 0.041). Moreover, the fasting insulin (δ: -1.81 ± 3.61 μU/mL, P = 0.017) and homeostasis model assessment for insulin resistance (HOMA-IR) (δ: -0.87 ± 1.57, P = 0.009) levels decreased at 8 weeks, and body weight significantly decreased from 67.20 ± 8.29 kg to 66.43 ± 8.12 kg (P = 0.008). Body mass index (BMI) also decreased in accordance with this (from 25.59 ± 1.82 kg/m² to 25.30 ± 1.86 kg/m², P = 0.009), as did waist circumference (δ: -1.31 ± 2.04 cm, P = 0.003). CONCLUSIONS: The consumption of diabetes-specific ONS with allulose in overweight or obese patients with T2DM improved glycemic profiles, such as FBG, HbA1c, and HOMA-IR, and reduced body weight and BMI.

• 한국구조물진단유지관리공학회 논문집
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• 제27권3호
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• pp.12-20
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• 2023

본 연구에서는 영구 교좌장치가 설치되는 교량의 교각 상부에서 FCM에 의한 상부공 시공에 주로 적용하고 있는 "내부 프리스트레싱 긴장재에 의한 임시 고정시스템"에서 강봉에 도입한 긴장력의 변화와 주두부의 기울음 특성을 분석하여 안정성 확보 방안에 대한 기초자료를 제시하였다. 상기 시스템은 시공 중 불균형 모멘트에 의하여 발행하는 상향력에 저항하기 위하여 교각과 교각 상부의 PSC BOX 내부에 연직으로 강봉을 설치한 후 상부에서 인장 및 정착하기 때문에, 그 동안 강봉에 도입한 긴장력의 변화와 주두부의 기울음 정도를 확인하기 어려웠다. 따라서, 강봉의 길이 변화 및 주두부 변위에 대한 계측 및 분석은 미세 측정이 가능한 FBG 센서를 활용하여 각 세그먼트 진행의 전후에 수행하였다. 강봉의 계산 인장력과 잔존 인장력을 비교한 결과 안전율은 모든 교량에서 저하하였다. 그 원인은 주로 강봉의 정착 과정에서부터 1세그먼트 완료까지의 초기 긴장력 손실로 확인되어 이에 대한 대책을 제시하였다. 주두부의 미세 기울음 특성을 분석한 결과 안전율이 충분히 확보된 교량에서도 세그먼트의 진행에 따라 미세 기울음이 증가되는 양상을 보였으며, 세그먼트 진행 단계별로 콘크리트 타설 전,후의 차이도 뚜렸하게 확인되었다. 또한, 모든 교량에서 미세 기울음의 증가는 강봉의 긴장력 손실과 밀접한 관계를 보이며 기울음 측면과 반대 측면의 응력 감소가 더욱 크게 나타났다. 이러한 현상의 원인은 불균형모멘트에 의하여 기울음 측면과의 반대 측면의 강봉에 상향 인장력이 발생하여 강봉의 응력 차이를 유발시킨 때문으로 판단된다.

• Smart Structures and Systems
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• 제20권4호
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• pp.441-450
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• 2017

The objective of this work is to present a conceptual design and the modelling of a distributed sensor system based on fiber optic devices (Fiber Bragg Grating, FBG), aimed at measuring span-wise and chord-wise variations of an adaptive (morphing) trailing edge. The network is made of two different integrated solutions for revealing deformations of the reference morphing structure. Strains are confined to typical values along the span (length) but they are expected to overcome standard ranges along the chord (width), up to almost 10%. In this case, suitable architectures may introduce proper modulations to keep the measured deformation low while preserving the information content. In the current paper, the designed monitoring system combines the use of a span-wise fiber reinforced patch with a chord-wise sliding beam. The two elements make up a closed grid, allowing the reconstruction of the complete deformed shape under the acceptable assumption that the transformation refers to regular geometry variations. Herein, the design logic and some integration issues are reported. Preliminary experimental test results are finally presented.