• Journal of Korean Society for Geospatial Information Science
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• v.7 no.1 s.13
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• pp.87-95
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• 1999

The min object of this study was to prove the effectiveness of PCA(principal component analysis) merged images produced by PCA method using high resolution IRS-1C PAN data and multispectral Landsat TM data A sample data which has ten classes was generated for evaluation of the overall classification accuracy. In result, merged sample image which TM13457 bands with IRS-1C PAN data by PCA method showed best result (95.1%). Especially, the largest improve (6.2%) in classification accuracy was resulted when IRS-1C PAN data was merged with TM123457 or TM13457 images. In addition, landuse classification accuracy of the PCA merged images was improved (5.16%) than original color composite images of Landsat TM data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.2
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• pp.187-194
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• 1998

In this study, effective multispectral Landsat TM band combinations for a merging with the high resolution IRS-1C PAN data using the IHS method to improve landuse accuracy is discussed. From the pre-classified image using the merged images with TM all six band images(with the exception of band 6 image) and PAN image, a sample data which has ten classes was generated. An evaluation of the overall classification accuracy for the representative seven merged images which were merged using each TM three-band images and IRS-1C PAN image by IHS method for the sample area. The increase in classification accuracy is most significant with the inclusion of two of TM4, TM5 and TM7 infrared band images. Especially, the largest increase(11.8 percent) in landuse classification accuracy were investigated when Landsat TM247 bands were merged with IRS-1C PAN data. The classification accuracy when TM three band image and PAN image were used without merging is higher than result of the case of using the merged images.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.4
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• pp.373-383
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• 2001

This study conducted pilot mapping project to know the possibility of mapping with medium resolution satellite imageries. For this purpose, mapping experiments were conducted with each stereo model imageries of SPOT, KOMPSAT, and IRS- lC. And positional accuracy, analysis of detectable and describable features, and comparison with existing digital map were checked, possible mapping scale and cost analysis were conducted with these results. Regarding SPOT imagery, digital photogrammetric workstation was used for stereoplotting. Regarding KOMPSAT and IRS-lC imageries, because there were data format support problems. head-up digitizing was performed with ortho imageries rectified with DEMs generated by image matching. The results of experiments show that such features as wide road, river, coast line, etc are possible to detect and depict but many other features are not for SPOT, KOMPSAT, and IRS-lC imageries. On the aspect of mapping, therefore, SPOT is available for 1/50,000 topographic map revision, KOMPSAT and IRS-lC for 1/25.000 topographic map revision.

• Journal of Yeungnam Medical Science
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• v.36 no.1
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• pp.26-35
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• 2019

Background: Dysregulation of hepatic glucose production (HGP) contributes to the development of type 2 diabetes mellitus. Telmisartan, an angiotensin II type 1 receptor blocker (ARB), has various ancillary effects in addition to common blood pressure-lowering effects. The effects and mechanism of telmisartan on HGP have not been fully elucidated and, therefore, we investigated these phenomena in hyperglycemic HepG2 cells and high-fat diet (HFD)-fed mice. Methods: Glucose production and glucose uptake were measured in HepG2 cells. Expression levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase ${\alpha}$ ($G6Pase-{\alpha}$), and phosphorylation levels of insulin receptor substrate-1 (IRS-1) and protein kinase C ${\zeta}$ ($PKC{\zeta}$) were assessed by western blot analysis. Animal studies were performed using HFD-fed mice. Results: Telmisartan dose-dependently increased HGP, and PEPCK expression was minimally increased at a $40{\mu}M$ concentration without a change in $G6Pase-{\alpha}$ expression. In contrast, telmisartan increased phosphorylation of IRS-1 at Ser302 ($p-IRS-1-Ser^{302}$) and decreased $p-IRS-1-Tyr^{632}$ dose-dependently. Telmisartan dose-dependently increased $p-PKC{\zeta}-Thr^{410}$ which is known to reduce insulin action by inducing IRS-1 serine phosphorylation. Ectopic expression of dominant-negative $PKC{\zeta}$ significantly attenuated telmisartan-induced HGP and $p-IRS-1-Ser^{302}$ and -inhibited $p-IRS-1-Tyr^{632}$. Among ARBs, including losartan and fimasartan, only telmisartan changed IRS-1 phosphorylation and pretreatment with GW9662, a specific and irreversible peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) antagonist, did not alter this effect. Finally, in the livers from HFD-fed mice, telmisartan increased $p-IRS-1-Ser^{302}$ and decreased $p-IRS-1-Tyr^{632}$, which was accompanied by an increase in $p-PKC{\zeta}-Thr^{410}$. Conclusion: These results suggest that telmisartan increases HGP by inducing $p-PKC{\zeta}-Thr^{410}$ that increases $p-IRS-1-Ser^{302}$ and decreases $p-IRS-1-Tyr^{632}$ in a $PPAR{\gamma}$-independent manner

• YAKHAK HOEJI
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• v.52 no.3
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• pp.182-187
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• 2008

Salicylate (SA) was shown to alleviate insulin resistance. Here, we showed that SA inhibited Ser731 phosphorylation of insulin receptor substrate 1 (IRS1) and S6 kinase activation, and enhanced tyrosine phosphorylation of IRS1 in response to insulin or amino acid. Experiments using a cJun N-terminal kinase (JNK)-deficient cell and an IRS1 JNK-binding mutant showed that JNK is not required for Ser731 phosphorylation. A two-week treatment of obese mice with SA resulted in decreased Ser731 phosphorylation and enhanced insulin signaling. These results suggest that SA enhances insulin signaling by inhibiting Ser731 phosphorylation of IRS1.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.3
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• pp.293-300
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• 1999

The study aims to develope techniques for generating digital elevation model(DEM) from IRS-1C PAN stereo image data. The bundle adjustment technique was used to determine the satellite exterior orientation parameters as a function of along-track lines. The first degree of polynomial was selected as a function of satellite attitude and position for each scan line. To evaluate the DEM and orthoimage generated, the resulted three dimensional coordinates of the 16 elevation points were computed with the map coordinates. The elevation test showed that root mean square errors of the DEM elevation was about $\pm{16.66m}$ meters.

• Molecules and Cells
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• v.38 no.4
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• pp.356-361
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• 2015

Mitochondrial dysfunction is associated with insulin resistance and diabetes. We previously showed that retinoid X receptor ${\alpha}$ ($RXR{\alpha}$) played an important role in transcriptional regulation of oxidative phosphorylation (OXPHOS) genes in cells with mitochondrial dysfunction caused by mitochondrial DNA mutation. In this study, we investigated whether mitochondrial dysfunction induced by incubation with OXPHOS inhibitors affects insulin receptor substrate 1 (IRS1) mRNA and protein levels and whether $RXR{\alpha}$ activation or overexpression can restore IRS1 expression. Both IRS1 and $RXR{\alpha}$ protein levels were significantly reduced when C2C12 myotubes were treated with the OXPHOS complex inhibitors, rotenone and antimycin A. The addition of $RXR{\alpha}$ agonists, 9-cis retinoic acid (9cRA) and LG1506, increased IRS1 transcription and protein levels and restored mitochondrial function, which ultimately improved insulin signaling. $RXR{\alpha}$ overexpression also increased IRS1 transcription and mitochondrial function. Because $RXR{\alpha}$ overexpression, knock-down, or activation by LG1506 regulated IRS1 transcription mostly independently of mitochondrial function, it is likely that $RXR{\alpha}$ directly regulates IRS1 transcription. Consistent with the hypothesis, we showed that $RXR{\alpha}$ bound to the IRS1 promoter as a heterodimer with peroxisome proliferator-activated receptor ${\delta}$ ($PPAR{\delta}$). These results suggest that $RXR{\alpha}$ overexpression or activation alleviates insulin resistance by increasing IRS1 expression.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.39.1-39.1
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• 2018

We present our observational attempts to precisely measure the central mass of a proto-brown dwarf candidate, L328-IRS, in order to investigate whether L328-IRS is in the substellar mass regime. Observations were made for the central region of L328-IRS with the dust continuum and CO isotopologue line emission at ALMA band 6, discovering the detailed outflow activities and a deconvolved disk structure of a size of ${\sim}87AU{\times}{\sim}37AU$. We investigated the rotational velocities as a function of the disk radius, finding that its motions between 130 AU and 60 AU are partially fitted with a Keplerian orbit by a stellar object of ${\sim}0.30M_{\odot}$, while the motions within 60 AU do not follow any Keplerian orbit at all. This makes it difficult to lead a reliable estimation of the mass of L328-IRS. Nonetheless, our ALMA observations were useful enough to well constrain the inclination angle of the outflow cavity of L328-IRS as ${\sim}66^{\circ}$ degree, enabling us to better determine the mass accretion rate of ${\sim}8.9{\times}10^{-7}M_{\odot}yr-1$.From assumptions that the internal luminosity of L328-IRS is mostly due to this mass accretion process in the disk, or that L328-IRS has mostly accumulated the mass through this constant accretion rate during its outflow activity, its mass was estimated to be ${\sim}0.012-0.023M_{\odot}$, suggesting L328-IRS to be a substellar object. However, we leave our identification of L328-IRS as a proto-brown dwarf to be tentative because of various uncertainties especially regarding the mass accretion rate.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.63.2-63.2
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• 2014

As a part of the "Dust, Ice, and Gas In Time" (DIGIT) key program on Herschel, we observed GSS30-IRS1, a Class I protostar located in Ophiuchus (d =125 pc), with Herschel/Photodetector Array Camera and Spectrometer (PACS). More than 70 lines were detected within a wavelength range from 50 ${\mu}m$ to 200 ${\mu}m$: CO lines from J = 14-13 to 41-40, several $H_2O$ lines of Eup = 100 K to 1500 K, 16 transitions of OH rotational lines, and two atomic [O I] lines at 63 and 145 ${\mu}m$. The [C II] line, known as a tracer of externally heated gas by the interstellar radiation field, is also detected at 158 ${\mu}m$. All lines, except [O I] and [C II], are detected only at the central spaxel of $9^{\prime\prime}.4{\times}9^{\prime\prime}.4$. The [O I] emission is extended along a NE-SW orientation, which is consistent with the known outflow direction, while the [C II] line is detected over all spaxels. One possible explanation of the detection of the [C II] line and no correlation of its spatial distribution with any other molecular emission is the existence of the enhanced ISRF nearby GSS30-IRS1. One interesting feature of GSS30-IRS1 is that the continuum emission is extended beyond the point-spread function (PSF), unlike the molecular line emission, indicative of significant external heating. The best-fit continuum model of GSS30-IRS1 with the physical structure including flared disk, envelope, and outflow shows that the internal luminosity is 11 $L_{\odot}$, and the region is also externally heated by a radiation field enhanced by a factor of 25 compared to the local standard interstellar field.

• Korean Journal of Veterinary Research
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• v.49 no.2
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• pp.105-111
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• 2009

In this study, occurrence of canine brucellosis was surveyed in kennels, indoor dogs and stray dogs in Korea, and infrequent restriction site-polymerase chain reaction (IRS-PCR) was applied to analyze DNA polymorphism of Brucella canis (B. canis) isolates. Among a total of 501 dogs tested, B. canis antibodies by both rapid screening agglutination with 2-mercaptoethanol (2-ME RSAT) and immunochromatographic assay were detected in only 14.1% of kennel dogs. There were no seropositive cases in indoor dogs and stray dogs. DNA polymorphism was observed in 16 B. canis isolates by the IRS-PCR. Sixteen isolates were tested with primers, PsalA, PsalC, PsalG and PsalT, and different primers produced different DNA patterns. In regard to the IRS-PCR pattern of 16 isolates, 9 (56.3%) belonged to the IRS-PCR type I. The remaining 7 were differentiated as type II, III and IV. An application of the primer PsalC provided discrimination between B. canis isolated in 2005 and others.