Excited state intramolecular proton transfer (ESIPT) of 1-hydroxy-2-acetonaphthone (HAN) has been in controversy, mainly because its Stokes shift is small compared to those of typical ESIPT ...molecules. We have investigated excited state dynamics of HAN by time-resolved fluorescence with a resolution high enough to record the nuclear wave packet motions in the excited state. Population dynamics of both the normal and tautomer forms were recorded together with the wave packet motions of the tautomer in the excited state, which confirm the ESIPT of HAN. The population dynamics of the normal and tautomer forms imply that the ESIPT dynamics is biphasic with two time constants <25 and 80 fs. Theoretical analysis of the vibrational modes of the tautomer excited impulsively reveals that major part of the change for the ESIPT reaction is on the naphthalene ring.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
This paper proposes a method for forecasting surface solar irradiance (SSI), the most critical factor in solar photovoltaic (PV) power generation. The proposed method uses 16-channel data obtained by ...the GEO-KOMPSAT-2A (GK2A) satellite of South Korea as the main data for SSI forecasting. To determine feature variables related to SSI from the 16-channel data, the differences and ratios between the channels were utilized. Additionally, to consider the fundamental characteristics of SSI originating from the sun, solar geometry parameters, such as solar declination (SD), solar elevation angle (SEA), and extraterrestrial solar radiation (ESR), were used. Deep learning-based feature selection (Deep-FS) was employed to select appropriate feature variables that affect SSI from various feature variables extracted from the 16-channel data. Lastly, spatio-temporal deep learning models, such as convolutional neural network–long short-term memory (CNN-LSTM) and CNN–gated recurrent unit (CNN-GRU), which can simultaneously reflect temporal and spatial characteristics, were used to forecast SSI. Experiments conducted to verify the proposed method against conventional methods confirmed that the proposed method delivers superior SSI forecasting performance.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Campylobacter jejuni is one of the leading bacterial causes of human gastroenteritis. Due to the increasing rates of human campylobacteriosis, C. jejuni is considered as a serious public health ...concern worldwide. C. jejuni is a microaerophilic, fastidious bacterium. C. jejuni must overcome a wide range of stress conditions during foodborne transmission to humans, such as food preservation and processing conditions, and even in infection of the gastrointestinal tracts of humans. Particularly, this microaerophilic foodborne pathogen must survive in the atmospheric conditions prior to the initiation of infection. C. jejuni possesses unique regulatory mechanisms for oxidative stress resistance. Lacking OxyR and SoxRS that are highly conserved in other Gram-negative foodborne pathogens, C. jejuni modulates the expression of genes involved in oxidative stress resistance mainly via the peroxide resistance regulator and Campylobacter oxidative stress regulator. Based on recent findings of ours and others, in this review, we described how C. jejuni regulates the expression of oxidative stress defense.
In modern complex industrial processes, mode changes cause unplanned shutdowns, potentially shortening the lifespan of key equipment and incurring significant maintenance costs. To avoid this ...problem, a method that can detect the fault of equipment operating in various modes is required. Therefore, we propose a novel fault detection method that uses the k-nearest neighbor normalization-based weight local outlier factor (WLOF). The proposed method performs local normalization using neighbors to consider possible mode changes in the normal data and WLOF is used for fault detection. In contrast to statistical methods, such as principal component analysis (PCA) and independent component analysis (ICA), the local outlier factor (LOF) uses the density of neighbors. However, because LOF is significantly affected by the distance between its neighbors, the weight is multiplied proportionally to the distance between each neighbor to improve the fault detection performance of the LOF. The efficiency of the proposed method was evaluated using a multimode numerical case and a circulating fluidized bed boiler. The experimental results show that the proposed method outperforms conventional PCA, kernel PCA (KPCA), k-nearest neighbor (kNN), and LOF. In particular, the proposed method improved the detection accuracy by 20% compared with conventional methods. Therefore, the proposed method can be applied to a real process operating in multiple modes.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
There are several previous reports that infection or reactivation of varicella zoster virus (VZV) can occur after coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory ...syndrome coronavirus-2 (SARS-CoV-2). Herein, we report a rare case of VZV meningitis in breakthrough COVID-19. An 18-years-old male visited the emergency room, presenting with a headache and fever of up to 38.4°C for 5 days. He received the second dose of BNT162b2 mRNA SARS-CoV-2 vaccine 7 weeks prior to symptom onset. The symptoms persisted with headache, fever, and nausea. His cerebrospinal fluid (CSF) showed an elevated opening pressure of 27 cm H
O, 6/µL red blood cells, 234/µL white blood cells (polymorphonuclear leukocytes 3%, lymphocytes 83%, and other 14%), 43.9 mg/dL protein, and 59 mg/dL glucose, and CSF polymerase chain reaction (PCR) test was positive for VZV. Also, he was diagnosed with COVID-19 by reverse transcriptase-PCR examining upper and lower respiratory tract. We administered intravenous acyclovir for 12 days, and he was discharged without any neurologic complication.
Display omitted
•A current and voltage redistribution phenomenon by cell interaction is observed.•A one-dimensional model is developed to analyze cell interaction.•A multipoint voltage-monitoring ...method is proposed for fuel cell inconsistency analysis.•A specially designed stack is used to validate the model analysis.
Traditionally, only one set voltage monitor was used for fuel cell diagnosis and bipolar plate was regarded as the equipotential body. This study presents a novel analysis about this classic method, and proves that only one-set voltage monitor cannot obtain the real health status of every cell. Experimental results point out that the voltage of each cell along the cell gas channel is variable. The current and voltage redistribution phenomenon, caused by the cell interaction, was observed in the fuel cell stack with graphite bipolar plate. Thus, a one-dimensional model has been proposed to explain the mechanism of the current and voltage redistribution with cell interaction. Simulation result shows that, as long as the abnormal cell exists, the current and voltage distribution of the whole stack is significantly affected. Finally, a multipoint voltage-monitoring method has been developed for fuel cell consistency analysis. New method was applied in a specially designed four-cell stack to validate the model analysis. Additionally, the proposed method was used to diagnose anode starvation, which cannot be easily detected using only the one-set voltage monitor for the anode inlet. All experiments and modeling works prove that the multipoint voltage-monitoring method is effective for fuel cell consistency analysis.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
The role of HER2 amplification level in predicting the effectiveness of HER2-directed therapies has been established. However, its association with survival outcomes in advanced HER2-positive breast ...cancer treated with dual HER2-blockade remains unexplored.
This is a single-center retrospective study of patients with advanced HER2-positive breast cancer treated with first-line pertuzumab, trastuzumab, and docetaxel. The primary objective was to ascertain the relationship between treatment outcomes and the level of HER2 amplification by in situ hybridization (ISH).
A total of 152 patients were included with a median follow-up duration of 50.0 months. Among the 78 patients who received ISH, a higher HER2/CEP17 ratio correlated significantly with longer PFS (HR 0.50, p = 0.022) and OS (HR 0.28, p = 0.014) when dichotomized by the median. A higher HER2 copy number also correlated significantly with better PFS (HR 0.35, p < 0.001) and OS (HR 0.27, p = 0.009). In multivariate analysis, the HER2/CEP17 ratio was an independent predictive factor for PFS (HR 0.66, p = 0.004) and potentially for OS (HR 0.64, p = 0.054), along with HER2 copy number (PFS HR 0.85, p = 0.004; OS HR 0.84, p = 0.049). Furthermore, the correlation between HER2 amplification level by ISH with PFS and OS was consistent across the HER2 IHC 1+/2+ and 3+ categories.
This is the first study to report that a higher level of HER2 amplification by ISH is associated with improved PFS and OS in advanced HER2-positive breast cancer treated with dual HER2-blockade. Notably, HER2 amplification level had a predictive role regardless of IHC results. Even in patients with HER2 protein expression of 3+, treatment outcome to HER2-directed therapy was dependent on the level of HER2 gene amplification.
Ultrafine BaTiO3 nanoparticles and their highly stable sols are prepared by a novel and rapid route. In this method, the formation mechanism that lies between the chemical precipitation and the ...sol–gel process is proposed. The BaTiO3 nanocrystal sols are synthesized in as fast as 15 min in an air atmosphere. Dynamic light scattering analysis and the observation of the Tyndall effect confirm the existence of crystalline nanoparticles in these sols. After careful separation, nanocrystalline BaTiO3 powders with an average particle size as small as 2.8 nm are obtained. These particles have perovskite phase structures as determined by X‐ray diffraction and selected‐area electron‐diffraction analysis. Fourier transform infrared spectroscopy (FT‐IR) and thermal analysis are used to detect the characteristic functional groups of the solvents on the particles to reveal the formation mechanism. Uniform BaTiO3 nanocrystal films with high dielectric constants, low dielectric losses, and paraelectric behavior are prepared through solvent evaporation of the nanocrystal sols, providing a new low‐temperature route for the fabrication of perovskite thin films.
Full text
Available for:
BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Paraquat is associated with a high rate of fatalities in acute poisoning. This study aimed to examine the association between the national public health policy that banned the use of paraquat and the ...incidence of pesticide-associated mortality.
All external causes of death from 2009 to 2013 of Korea were analyzed. The intervention was a national public health policy that annulled the authorized use (2011) and banned the purchase of paraquat (2012). Two periods were compared as follows: before (2009-2010) and after (2012-2013) the intervention period. The main outcome was pesticide-associated death coded on the death certificate. Multivariable logistic regression analysis adjustment for gender, age, season and weekday of death, province, education level, marital status, and occupation was performed to calculate adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for pesticide-associated mortality. The effect sizes of the intervention across all intents (Accident, Suicide, Homicide, and Undetermined) were compared by adding an interaction term (intervention*intent group) to the above model.
A total of 127,866 deaths from for all external causes were analyzed, including 65,538 from 2009 to 2010 and 62,373 from 2012 to 2013. Pesticide-associated mortality decreased from 9.7% (2009-2010) to 6.5% (2012-2013) (p < 0.001). The AOR (95% CI) of the intervention on pesticide-associated mortality was 0.59 (0.56-0.62). The AORs of the intervention according to intent were 0.72 (0.55-0.96) in the Accident group, 0.61 (0.58-0.64) in the Suicide group, 1.29 (0.43-3.87) in the Homicide group, and 0.44 (0.38-0.50) in the Undetermined group.
The national public health policy that banned paraquat resulted in a significant decrease in pesticide-associated mortality.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Particulate matter (PM) in the air can cause various health problems and diseases in humans. In particular, the smaller size of PM2.5 enable them to penetrate deep into the lungs, causing severe ...health impacts. Exposure to PM2.5 can result in respiratory, cardiovascular, and allergic diseases, and prolonged exposure has also been linked to an increased risk of cancer, including lung cancer. Therefore, forecasting the PM2.5 concentration in the surrounding is crucial for preventing these adverse health effects. This paper proposes a method for forecasting the PM2.5 concentration after 1 h using bidirectional long short-term memory (Bi-LSTM). The proposed method involves selecting input variables based on the feature importance calculated by random forest, classifying the data to assign weight variables to reduce bias, and forecasting the PM2.5 concentration using Bi-LSTM. To compare the performance of the proposed method, two case studies were conducted. First, a comparison of forecasting performance according to preprocessing. Second, forecasting performance between deep learning (long short-term memory, gated recurrent unit, and Bi-LSTM) and conventional machine learning models (multi-layer perceptron, support vector machine, decision tree, and random forest). In case study 1, The proposed method shows that the performance indices (RMSE: 3.98%p, MAE: 5.87%p, RRMSE: 3.96%p, and R2:0.72%p) are improved because weights are given according to the input variables before the forecasting is performed. In case study 2, we show that Bi-LSTM, which considers both directions (forward and backward), can effectively forecast when compared to conventional models (RMSE: 2.70, MAE: 0.84, RRMSE: 1.97, R2: 0.16). Therefore, it is shown that the proposed method can effectively forecast PM2.5 even if the data in the high-concentration section is insufficient.