40 research outputs found
PCT-CycleGAN: Paired Complementary Temporal Cycle-Consistent Adversarial Networks for Radar-Based Precipitation Nowcasting
The precipitation nowcasting methods have been elaborated over the centuries
because rain has a crucial impact on human life. Not only quantitative
precipitation forecast (QPF) models and convolutional long short-term memory
(ConvLSTM), but also various sophisticated methods such as the latest MetNet-2
are emerging. In this paper, we propose a paired complementary temporal
cycle-consistent adversarial networks (PCT-CycleGAN) for radar-based
precipitation nowcasting, inspired by cycle-consistent adversarial networks
(CycleGAN), which shows strong performance in image-to-image translation.
PCT-CycleGAN generates temporal causality using two generator networks with
forward and backward temporal dynamics in paired complementary cycles. Each
generator network learns a huge number of one-to-one mappings about
time-dependent radar-based precipitation data to approximate a mapping function
representing the temporal dynamics in each direction. To create robust temporal
causality between paired complementary cycles, novel connection loss is
proposed. And torrential loss to cover exceptional heavy rain events is also
proposed. The generator network learning forward temporal dynamics in
PCT-CycleGAN generates radar-based precipitation data 10 minutes from the
current time. Also, it provides a reliable prediction of up to 2 hours with
iterative forecasting. The superiority of PCT-CycleGAN is demonstrated through
qualitative and quantitative comparisons with several previous methods.Comment: CIKM 202
Calcinosis Cutis at the Tarsus of the Upper Eyelid
Calcinosis cutis involves the inappropriate deposition of calcium within the dermis layer of the skin, and is often associated with rheumatoid disease. A 42-year-old woman presented for evaluation of a hard palpable mass on the left upper eyelid. After everting the eyelid, a large papillomatous mass with a broad base was identified on the superior area of the tarsus. The lesion was partially excised posteriorly under local anesthesia, and pathologists identified the mass as calcinosis cutis. The patient had no systemic or trauma history, and the serum levels of calcium and phosphorous were normal. Idiopathic calcinosis cutis should be included in the differential diagnosis for a protruding papillomatous mass of the tarsal plate, and surgical debulking could be a viable option for large protruding lesions, although more follow-up is necessary to monitor regrowth
Naturally occurring radioactive materials (NORM) in the groundwater of two islands with various geologic settings in South Korea
Since 2007, Naturally Occurring Radioactive Materials (NORM) such as uranium-238 and radon-222 etc. in groundwater from the Community Water-supply Systems (CWS) in two islands have been studied in South Korea. In 71 samples from Ganghwa (G) Island, the maximum value of uranium-238 concentration is 72.21 μg/L. 3 CWSs (4.2%) exceeded the Maximum Contaminant Level (MCL) of 30 μg/L for uranium-238. The maximum value of radon-222 activity is 614 Bq/L. 28 CWSs (39.4 %) did not meet the United States Environment Protection Agency (US EPA) proposed Alternative Maximum Contaminant Level (AMCL) of 148 Bq/L for radon-222. At all CWS that did not meet the US EPA’s MCL or AMCL, some appropriate actions were taken such as water treatment, alternative well development, mixing water of different origins, and so forth. In the 52 CWSs of Jeju (J) Island, the maximum value of uranium-238 and radon-222 concentrations are 1.37 μg/L and 94.83 Bq/L, respectively. All values for uranium-238, gross alpha, and radon-222 meet MCL and proposed AMCL of US EPA drinking water standard. The two islands have different geological settings that are believed to be the causes of the big differences in the NORM levels. Geologically an old island has much higher NORM values than a young island formed in the Quaternary Period due to hydrogeological factors such as recharge and infiltration rates of precipitation. The residence times in the aquifers for water-rock (mineral) interactions are very different from each other.</p
A Novel BEST1 Mutation in Autosomal Recessive Bestrophinopathy
Citation: Lee CS, Jun I, Choi S, et al. A novel BEST1 mutation in autosomal recessive bestrophinopathy. Invest Ophthalmol Vis Sci. 2015;56:8141-8150. DOI:10.1167/iovs.15-18168 PURPOSE. To describe the clinical characteristics associated with a newly identified mutant of autosomal recessive bestrophinopathy (ARB) and confirm the associated physiological functional defects. METHODS. Two patients with ARB from one family underwent a full ophthalmic examination, including dilated fundus examination, fundus photography, fluorescein angiography, fundus autofluorescence imaging, spectral-domain optical coherence tomography (OCT), electroretinography (ERG), and electrooculography (EOG). Subsequently, genetic analysis for bestrophin-1 (BEST1) mutations was conducted through direct Sanger sequencing. The effect of ARB-associated mutations of BEST1 on the cellular localization was determined by in vitro experiments. Whole-cell patch clamping was conducted to measure the chloride conductance of wild-type BEST1 and the identified BEST1 mutants in transfected HEK293T cells. RESULTS. Two related patients (66-year-old brother and 52-year-old sister) presented with reduced visual acuity and bilateral symmetrical subretinal deposits of hyperautofluorescent materials in the posterior pole. Spectral-domain OCT showed macular thinning with submacular fluid. The female patient had a concomitant macular edema associated with branched retinal vein occlusion in the left eye, which responded well to intravitreal bevacizumab injections. Genetic analysis demonstrated that both patients were compound heterozygous for one novel (Leu40Pro) and one previously identified (Ala195Val) BEST1 variant. HEK293T cells transfected with the identified BEST1 mutant showed significantly small currents compared to those transfected with the wild-type gene, whereas cells cotransfected with mutant and wild-type BEST1 showed good chloride conductance. Cellular localization of BEST1 was well conserved to the plasma membrane in the mutants. CONCLUSIONS. We have identified and described the phenotype and in vitro functional aspects of a new BEST1 mutation causing ARB. Clinically suspected ARB cases warrant genetic confirmation to confirm the diagnosis
Assessment of re-entry survivability of aluminum oxide with different nanostructures considering surface catalytic heat-transfer
Re-entry survivability analysis is generally performed with the assumption of a smooth surface, for which the effect of surface roughness can be ignored. In such an approach, analysis may not provide accurate estimation of the survivability analysis of the re-entry object. The material surface roughness is known to enhance the surface catalytic properties of the material and thus results in a higher heat transfer. The present work incorporates the influence of surface roughness into the re-entry analysis in terms of surface catalytic recombination efficiency. The material catalytic efficiency value is obtained by using catalytic heat transfer theory in the shock tube end-wall heat transfer measurement. The material considered in the analysis is aluminum oxide with various levels of surface roughness. The roughness is varied by mechanical abrasion by using silicon carbide (SiC) sandpaper. The quality of the material is also assessed with different characterization techniques that include EDS, XPS, and AFM measurement. Through experimental measurement, it is observed that the surface catalytic recombination efficiency increases as the surface roughness level increases. Using the obtained efficiency values, the re-entry survivability analysis shows that a material with a high level of surface roughness exhibits a low survivability rate
Effects of Experimental Throughfall Exclusion on Soil Respiration in a Continental Coniferous Stand, South Korea
Severe droughts and changing precipitation patterns could alter the biogeochemical properties of the soil, affecting soil carbon cycles in forest ecosystems. A throughfall exclusion (TFE) experiment was conducted in a continental climate coniferous stand in Gangwon Province, Korea, to examine the effects of excluding rainfall on total soil respiration (SR), heterotrophic soil respiration (HR), autotrophic soil respiration (AR), sapling diameter growth, and soil bacterial communities from July 2016 to October 2017. The soil water content (SWC) was significantly decreased by the exclusion of the throughfall, resulting in changes in the bacterial communities, and subsequently a decrease in HR. Although AR did not present significant differences between the control and TFE plots, the rate of sapling growth was significantly lower in the TFE plots compared with that in the control plots. An exponential function relating SR to soil temperature accounted for 0.61% and 0.82% of the variance in SR in the control and TFE plots, respectively (Q10 = 2.48 and 2.86, respectively). Furthermore, a multivariate nonlinear model based on soil temperature and SWC explained 0.89% and 0.88% of the variance in SR in the control and TFE plots, respectively. When soil temperature was high, SR showed high fluctuations due to SWC variation. However, when SWC was low, we detected relatively small fluctuations in SR due to soil temperature. The results of this study show that the activity of soil microbial and root respiration during the growing season may be lower under future drought conditions
Prediction accuracy of conventional and total keratometry for intraocular lens power calculation in femtosecond laser-assisted cataract surgery
Abstract This study evaluated the accuracy of total keratometry (TK) and standard keratometry (K) for intraocular lens (IOL) power calculation in eyes treated with femtosecond laser-assisted cataract surgery. The retrospective study included a retrospective analysis of data from 62 patients (91 eyes) who underwent uneventful femtosecond laser-assisted cataract surgery with Artis PL E (Cristalens Industrie, Lannion, France) IOL implantation by a single surgeon between May 2020 and December 2020 in Severance Hospital, Seoul, South Korea. The new IOLMaster 700 biometry device (Carl Zeiss Meditec, Jena, Germany) was used to calculate TK and K. The mean absolute error (MAE), median absolute error (MedAE), and the percentages of eyes within prediction errors of ± 0.25 D, ± 0.50 D, and ± 1.00 D were calculated for all IOL formulas (SRK/T, Hoffer-Q, Haigis, Holladay 1, Holladay 2, and Barrett Universal II). There was strong agreement between K and TK (intraclass correlation coefficient = 0.99), with a mean difference of 0.04 D. For all formulas, MAE tended to be lower for TK than for K, and relatively lower MAE and MedAE values were observed for SRK/T and Holladay 1. Furthermore, for all formulas, a greater proportion of eyes fell within ± 0.25 D of the predicted postoperative spherical equivalent range in the TK group than in the K group. However, differences in MAEs, MedAEs, and percentages of eyes within the above prediction errors were not statistically significant. In conclusion, TK and K exhibit comparable performance for refractive prediction in eyes undergoing femtosecond laser-assisted cataract surgery
Thermochemical nonequilibrium flow analysis in low enthalpy shock-tunnel facility.
A thermochemical nonequilibrium analysis was performed under the low enthalpy shock-tunnel flows. A quasi-one-dimensional flow calculation was employed by dividing the flow calculations into two parts, for the shock-tube and the Mach 6 nozzle. To describe the thermochemical nonequilibrium of the low enthalpy shock-tunnel flows, a three-temperature model is proposed. The three-temperature model treats the vibrational nonequilibrium of O2 and NO separately from the single nonequilibrium energy mode of the previous two-temperature model. In the three-temperature model, electron-electronic energies and vibrational energy of N2 are grouped as one energy mode, and vibrational energies of O2, O2+, and NO are grouped as another energy mode. The results for the shock-tunnel flows calculated using the three-temperature model were then compared with existing experimental data and the results obtained from one- and two-temperature models, for various operating conditions of the K1 shock-tunnel facility. The results of the thermochemical nonequilibrium analysis of the low enthalpy shock-tunnel flows suggest that the nonequilibrium characteristics of N2 and O2 need to be treated separately. The vibrational relaxation of O2 is much faster than that of N2 in low enthalpy condition, and the dissociation rate of O2 is manly influenced by the species vibrational temperature of O2. The proposed three-temperature model is able to describe the thermochemical nonequilibrium characteristics of N2 and O2 behind the incident and reflected shock waves, and the rapid vibrational freezing of N2 in nozzle expanding flows