• Advances in environmental research
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• v.9 no.1
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• pp.19-39
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• 2020

Urban heat island (UHI) is one of the most important climatic implications of urbanization and thus a matter of key concern for environmentalists of the world in the twenty-first century. The relationship between climate and urbanization has been better understood with the introduction of thermal remote sensing. So, this study is an attempt to understand the influence of urbanization on local temperature for a small developing city. The study focuses on the investigation of intensity of atmospheric and surface urban heat island for a small urbanizing district of Punjab, India. Landsat 8 OLI/TIRS satellite data and field observations were used to examine the spatial pattern of surface and atmospheric UHI effect respectively, for the month of April, 2018. The satellite data has been used to cover the larger geographical area while field observations were taken for simultaneous and daily temperature measurements for different land use types. The significant influence of land use/land cover (LULC) patterns on UHI effect was analyzed using normalized built-up and vegetation indices (NDBI, NDVI) that were derived from remote sensing satellite data. The statistical analysis carried out for land surface temperature (LST) and LULC indicators displayed negative correlation for LST and NDVI while NDBI and LST exhibited positive correlation depicting attenuation in UHI effect by abundant vegetation. The comparison of remote sensing and in-situ observations were also carried out in the study. The research concluded in finding both nocturnal and daytime UHI effect based on diurnal air temperature observations. The study recommends the urgent need to explore and impose effective UHI mitigation measures for the sustainable urban growth.

• Journal of Korean Neurosurgical Society
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• v.40 no.5
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• pp.323-329
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• 2006

Objective : This study was designed to analyze surgical strategies for patients with intractable supplementary sensorimotor area[SSMA] seizures. Methods : Seventeen patients who had surgical treatment were reviewed retrospectively. Preoperatively, phase I [non-invasive] and phase II [invasive] evaluation methods for epilepsy surgery were done. Seizure outcome was assessed with Engel's classification. The mean follow-up period was 27.2 months [from 12 months to 54 months]. Results : An MRI identified structural abnormality in eight patients and 3D-surface rendering revealed abnormal gyration in three. PET, SPECT, and surface EEG could not delineate the epileptogenic zone. Video-EEG monitoring with a subdural grid or depth electrodes verified the epileptogenic zone in all patients. Surgical procedures consisted of a resection of the SSMA and simultaneous callosotomy in two patients, a resection of the SSMA extending to the adjacent area in seven, a resection of a different area without a SSMA resection in seven, and a callosotomy in one. Seizure outcomes were class I in 11 [65%]. class II in five [29%], class III in one [6%]. Conclusion : In patients with intractable SSMA seizure, surgery was an excellent treatment modality. Precise delineation of the epileptogenic zone based on multimodal diagnostic methods can provide good surgical outcomes without neurological complications.

• Tunnel and Underground Space
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• v.6 no.4
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• pp.342-347
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• 1996

The changes of electromagnetic wave velocity in rock were monitored to investigate rock behaviors due to the drill & blasting excavations through georadar tomography during the construction of the underground rock laboratory (5 m wide, 6 m high, and 140 m long) at Mabuk-Ri, Goosung-Myun, Yongin-Si, Kyunggi-Do. Two horizontal boreholes spaced 1.4 m apart were drilled parallel to the test tunnel before excavating it, high-resolution crosshole georadar tomography with about 500 MHz electromagnetic waves was performed at pre-excavation phase (May, 1996) and post-excavation phase (August, 1996). The data were acquired with the combination of 34 sources and 44 receivers with space of 0.3 m. Only 11 continuous receivers were selectively utilized with one fixed source. Sampling interval was 0.4 ns and each trace has 512 samples. The first arrival of each trace was picked manually with a picking software. The total number of rays used in inversion amounted to 34x11 and the size of pixel was determined to be 0.3 m. As an inversion technique, SIRT(Simultaneous Iterative Reconstruction Technique) was applied in this study. The velocity of electromagnetic waves at post-excavation phase decreased as large as 15% in comparison with that at pre-excavation phase, which may be attributed to the creation of micro-cracks in rock due to excavations and saturation with groundwater. Small amount of borehole deviation made a critical effect in radar tomography. Totally different tomograms were created after borehole deviation corrections.

• Safety and Health at Work
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• v.11 no.3
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• pp.322-334
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• 2020

Background: Spontaneous combustion of coal is one of the factors which causes direct or indirect gas and dust explosion, mine fire, the release of toxic gases, loss of reserve, and loss of miners' life. To avoid these incidents, the prediction of spontaneous combustion is essential. The safety of miner's in the mining field can be assured if the prediction of a coal fire is carried out at an early stage. Method: Adularya Underground Coal Mine which is fully mechanized with longwall mining method was selected as a case study area. The data collected for 2017, by sensors from ten gas monitoring stations were used for the simulation and prediction of a coal fire. In this study, the fuzzy logic model is used because of the uncertainties, nonlinearity, and imprecise variables in the data. For coal fire prediction, CO, O₂, N₂, and temperature were used as input variables whereas fire intensity was considered as the output variable.The simulation of the model is carried out using the Mamdani inference system and run by the Fuzzy Logic Toolbox in MATLAB. Results: The results showed that the fuzzy logic system is more reliable in predicting fire intensity with respect to uncertainties and nonlinearities of the data. It also indicates that the 1409 and 610/2B gas station points have a greater chance of causing spontaneous combustion and therefore require a precautional measure. Conclusion: The fuzzy logic model shows higher probability in predicting fire intensity with the simultaneous application of many variables compared with Graham's index.

• Bulletin of the Korean Chemical Society
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• v.28 no.7
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• pp.1187-1194
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• 2007

The three major active isoflavonoids (calycosin-7-O-β -glucoside, isomucronulatol 7-O-β-glucoside, formononetin) and two main saponins (astragaloside I, astragaloside IV) in an extract of Radix Astragali were determined using rapid, sensitive, reliable HPLC/UV and LC-ESI-MS/MS methods. The separation conditions employed for HPLC/UV were optimized using a phenyl-hexyl column (4.6 × 150 mm, 5 μm) with the gradient elution of acetonitrile and water as the mobile phase at a flow rate of 1.0 mL/min and a detection wavelength of 230 nm. The specificity of the peaks was determined using a triple quadrupole tandem mass spectrometer equipped with an electrospray ionization (ESI) source that was operated in multiple reaction monitoring (MRM) in the positive mode. These methods were fully validated with respect to the linearity, accuracy, precision, recovery and robustness. The HPLC/UV method was applied successfully to the quantification of three major isoflavonoids in the extract of Radix Astragali. The results indicate that the established HPLC/UV and LC-ESI-MS/MS methods are suitable for the quantitative analysis and quality control of multi-components in Radix Astragali.

• Archives of Craniofacial Surgery
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• v.18 no.1
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• pp.46-49
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• 2017

Nevus sebaceus is a hamartoma of the sebaceous gland that occurs congenitally, from which various secondary tumors can arise with a prevalence of 5%-6%. Benign neoplasms commonly arise from nevus sebaceous, but they have a very low malignant potential. Two neoplasms may occasionally arise within the same lesion, but it is rare for three or more neoplasms to occur in a nevus sebaceus simultaneously. A 61-year-old male patient was admitted to our hospital for a $4cm\times2.5cm$ growing tumor in a verrucous form arising within a periauricular nevus sebaceus in the post auricle of the left ear that had developed 30 years earlier. The nodule was diagnosed as 3 different types of tumors: trichilemmoma, desmoplastic trichilemmoma, and basal cell carcinoma. To our knowledge, this is the first report of the coexistence of three different tumors arising from nevus sebaceous. It contain malignant neoplasm also. Surgeons should be aware of the need for close monitoring and early complete surgical excision of sebaceous nevus in order to improve patient outcomes.

• Journal of Dental Anesthesia and Pain Medicine
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• v.17 no.1
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• pp.71-76
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• 2017

Drug-induced sleep endoscopy (DISE) is used to identify areas of upper airway obstruction, which occurs when patients with obstructive sleep apnea (OSA) snore. DISE enables effective diagnosis and appropriate treatment of the obstruction site. Among surgical treatment methods for OSA, maxillomandibular advancement surgery (MMA) is performed to move a jaw forward; the surgery has a high success rate for OSA treatment. In DISE, anesthetics such as propofol and midazolam must be administered to induce snoring while the patient is deeply sedated for an accurate diagnosis to be made. When inducing deep sedation in a patient with OSA, airway obstruction may increase, causing oxygen saturation to drop; airway interventions are necessary in such cases. Effective DISE and MMA surgery can be performed by administering propofol through target-controlled infusion while monitoring the bispectral index (BIS).

• Journal of Environmental Impact Assessment
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• v.15 no.2
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• pp.121-127
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• 2006

The conventional water quality measurements by point sampling provide only site specific temporal water quality information but not the synoptic geographic coverage of water quality distribution. To circumvent these limitations in temporal and spatial measurements, the use of remote sensing is increasingly involved in the water quality monitoring research. In other to assess a trophic state of Yongdam reservoir using satellite imagery data, I obtained Landsat ETM data and water quality data on 16th September and 18th October 2001. The approach involved acquisition of water quality samples from boats at 33 sites on 16th September and 30 sites on 18th October 2001, simultaneous with Landsat-7 satellite overpass. The correlation coefficients between the DN values of the imagery and the concentrations of chlorophyll-a were analyzed. The visible bands(band 1,2,3) and near infrared band(band 4) data of September image showed the correlation coefficient values higher than 0.9. The October image showed the correlation coefficient values about 0.7 due to the atmospheric effect and low variation of chlorophyll-a concentration. Regression models between the chrophyll-a concentration and DN values of the Landsat imagery data have been developed for each image. The regression model was determined based on the spectral characteristics of chlorophyll, so the green band(band 2) and near infrared band(band 4) were selected to generate a trophic state map. The coefficient of determination(R2) of the regression model for 16th September was 0.95 and that of the regression model for 18th October was 0.55. According to the trophic state map made based on Aizaki's TSI and chlorophyll-a concentration, the trophic state of Yongdam reservoir was mostly eutrophic state during this study.

• Biomolecules & Therapeutics
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• v.15 no.4
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• pp.266-272
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• 2007

A rapid analytical method was developed to quantify very long-chain fatty acids (VLCFAs, C22:0, C24:0, C26:0) in human plasma with good sensitivity and specificity using tert-butyldimethylsilyl (TBDMS) derivatization and stable isotope GC-MS selective ion monitoring (GC-MS/SIM). Two-hundred and fifty ${\mu}L$ of plasma was fortified with deuterated stable isotope internal standards (d3-C22:0, d3-C24:0, d3-C26:0) and standard mixtures of chloroform and methanol, and then extracted with hexane and acetonitrile. To upper layer of liquid-liquid-extraction, N-(t-Butyldimethylsilyl)-N-methyltrifluoroacetamide was added and then heated to $60^{\circ}C$ for 30 min to produce the TBDMS derivatives. Derivatives of VLCFAs were analyzed by GC-MS/SIM. Calibration curves showed a linear relationship for the target compounds in the concentration range of $10^{-4}{\sim}2{\times}10^3\;{\mu}g/mL$ with the correlation coefficient ranging from 0.996 to 0.999. The limit of quantification for the plasma was $10^{-4}{\sim}2{\times}10^{-4}\;{\mu}g/mL$ (S/N=3). When applied to the plasma specimens of patients with peroxisomal disorder, X-linked adrenoleucodystropy (ALD, Mckusick 202370), the method clearly differentiated normal subjects from ALD patients. The C24:0/C22:0 and C26:0/C22:0 ratios were significantly elevated in the plasma of patients with X-linked ALD compared to normal subjects. The new developed method might be useful for a rapid and sensitive diagnosis of X-linked ALD and other peroxisomal disorders.

• Korean Journal of Veterinary Service
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• v.30 no.1
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• pp.13-21
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• 2007

An atmospheric pressure chemical ionization (APcI) LC/MS/MS method was developed for the simultaneous analysis of fluoroquinolones (norfloxacin, ciprofloxacin, enrofloxacin, danofloxacin) residues in eggs. The spiked and blank samples were extracted from whole eggs using 50mM phosphate buffer (pH 7.4). The extract was cleaned up by passage though $Oasis^{(R)}$ MAX extraction cartridge for solid-phase extraction followed by elution with 4% formic acid in methanol. The extract of sample was separated on a Waters $Atlantis^{TM}$ $dC_{18}$ reversed-phase column ($4.6{\times}150mm,\;5{\mu}m$) and analyzed by APcI positive mode mass spectrometry. The mobile phase consists of aqueous 0.2% nonafluoropentanoic acid (NFPA) and methanol. Multiple reaction monitoring (MRM) using the precursor to product ion combinations of m/z $320\;{\dashrightarrow}\;302,\;332\;{\dashrightarrow}\;314,\;360\;{\dashrightarrow}\;342$ and m/z $358\;{\dashrightarrow}\;340$ were used to quantify norfloxacin (NOR), ciprofloxacin (CIP), enrofloxacin (ENR) and danofloxacin (DAN), respectively. The limits of quantification (LOQ) were 7.8ppb for NOR, 8.5ppb for CIP, 8.9ppb for ENR, and 4.8ppb for DAN. Average recoveries of fortified sample at levels of 0.025 to 0.1 ppm were estimated 71.29% for NOR, 75.27% for CIP, 85.51% for ENR and 81.22% for DAN. These results could be applied for the confirmation and quantification in eggs.