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This study reports the solar light-driven activation of a bicyclic aminoxyl mediator to achieve C–C bond cleavage of a lignin model compound at room temperature using a donor–π-conjugated bridge–acceptor organic dye-based photoelectrochemical system.

A chemically sintered and binder-free paste of TiO2 nanoparticles (NPs) was prepared using a binary-liquid mixture of 1-octanol and CCl4. The 1:1 (v/v) complex of CCl4 and 1-octanol easily interacted chemically with the TiO2 NPs and induced the formation of a highly viscous paste. The as-prepared binary-liquid paste (PBL)-based TiO2 film exhibited the complete removal of the binary-liquid and residuals with the subsequent low-temperature sintering (~150°C) and UV-O3 treatment. This facilitated the fabrication of TiO2 photoanodes for flexible dye-sensitized solar cells (f-DSSCs). For comparison purposes, pure 1-octanol-based TiO2 paste (PO) with moderate viscosity was prepared. The PBL-based TiO2 film exhibited strong adhesion and high mechanical stability with the conducting oxide coated glass and plastic substrates compared to the PO-based film. The corresponding low-temperature sintered PBL-based f-DSSC showed a power conversion efficiency (PCE) of 3.5%, while it was 2.0% for PO-based f-DSSC. The PBL-based low- and high-temperature (500°C) sintered glass-based rigid DSSCs exhibited the PCE of 6.0 and 6.3%, respectively, while this value was 7.1% for a 500°C sintered rigid DSSC based on a commercial (or conventional) paste.

High-fat diet (HFD) consumption is closely associated with an increased risk of metabolic syndromes (MetS), such as obesity, type 2 diabetes, and cardiovascular diseases (CVDs). Therefore, the consumption of alternative and functional fatty acids to replace saturated fatty acids and/or

Appendiceal mucocele is an obstructive dilatation of the appendix caused by abnormal accumulation of mucoid material. Its incidence is 0.2-0.3% of all appendectomy specimens and it does not have typical clinical features. It can mimic acute appendicitis in patients with right lower quadrant pain. Some patients have appendiceal mucocele with acute appendicitis. For this condition, 25% of cases were asymptomatic and were discovered incidentally on ultrasound examination, computed tomography, or colonoscopy due to nonspecific abdominal symptoms. Ultrasound examination or computed tomography is an important diagnostic tool for accurate preoperative diagnosis. If mucocele is treated incorrectly, pseudomyxoma peritonei may develop. The present study reports a case of a 79-year-old male with constipation. Ultrasonography showed a typical layered echogenic pattern of the appendiceal wall (onion sign or onion skin sign), which suggested appendiceal mucocele. Computed tomography showed a dilated appendix filled with low-attenuated material, indicating a pathologic diagnosis of low-grade appendiceal mucinous neoplasm.

Pancreas tail lesions are often missed on ultrasound examination. Several scan techniques can be used to detect pancreas tail lesions, such as epigastric oblique scans, transsplenic scans, and left subcostal transverse scans with a right lateral decubitus position. Some pancreas tail lesions are detected on left subcostal transverse scans with a right lateral decubitus position that are not detected with other scan techniques. Thus, left subcostal transverse scans with a right lateral decubitus position are better than other scan techniques for detecting pancreas tail lesions.

The present study aimed to evaluate the performance of automated skeletal maturation assessment system for Fishman’s skeletal maturity indicators (SMI) for the use in dental fields. Skeletal maturity is particularly important in orthodontics for the determination of treatment timing and method. SMI is widely used for this purpose, as it is less time-consuming and practical in clinical use compared to other methods. Thus, the existing automated skeletal age assessment system based on Greulich and Pyle and Tanner-Whitehouse3 methods was further developed to include SMI using artificial intelligence. This hybrid SMI-modified system consists of three major steps: (1) automated detection of region of interest; (2) automated evaluation of skeletal maturity of each region; and (3) SMI stage mapping. The primary validation was carried out using a dataset of 2593 hand-wrist radiographs, and the SMI mapping algorithm was adjusted accordingly. The performance of the final system was evaluated on a test dataset of 711 hand-wrist radiographs from a different institution. The system achieved a prediction accuracy of 0.772 and mean absolute error and root mean square error of 0.27 and 0.604, respectively, indicating a clinically reliable performance. Thus, it can be used to improve clinical efficiency and reproducibility of SMI prediction.

We have developed compact implicit finite-difference (FD) schemes in the time-space domain based on the second-order FD approximation for accurate solution of the acoustic wave equation in 1D, 2D, and 3D. Our method is based on the weighted linear combination of the second-order FD operators with different spatial orientations to mitigate numerical error anisotropy and the weighted averaging of the mass acceleration term over the grid points of the second-order FD stencil to reduce the overall numerical dispersion error. We have developed a derivation of the schemes for 1D, 2D, and 3D cases. We obtain their corresponding dispersion equations, then we find the optimum weights by optimization of the time-space domain dispersion function, and finally we tabulate the optimized weights for each case. We analyze the numerical dispersion, stability, and convergence rates of our schemes and compare their numerical dispersion characteristics with the standard high-order ones. We also discuss the efficient solution of the system of equations associated with our implicit schemes using the conjugate-gradient method. The comparison of dispersion curves and the numerical solutions with the analytical and the pseudospectral solutions reveals that our schemes have better performance than the standard spatial high-order schemes and remain stable for relatively large time steps.

Organic-inorganic hybrid lead halide perovskite materials with the general formula MAPbI3-nBrn (n = 0, 1, 2, and 3) exhibiting a range of crystal structures and a wide range of optical bandgaps are explored for their potential to harvest energy from ambient light sources. The replacement of I− with Br− is found to transform the perovskite crystal structure from the tetragonal for MAPbI3 to the pseudo cubic for MAPbI2Br and MAPbIBr2 and cubic for MAPbBr3 while increasing the optical bandgap from 1.59 eV to 2.31 eV. Photovoltaic cells (PVCs) are constructed using these perovskites and are found to exhibit power conversion efficiencies (PCEs) of 29.83 (MAPbI3), 23.75 (MAPbI2Br), 21.47 (MAPbIBr2), and 19.94% (MAPbBr3) under LED light illumination (1000 lux; ~0.371 mW cm−2), with a record high open-circuit voltage (VOC) of 1.15 V being observed for the MAPbBr3. The effect of crystal structure variation on the charge carrier mobility, trap states, recombination losses, photovoltaic properties, and operational stabilities has been investigated systematically under indoor illumination. Overall, this work provides a clear vision on the influence of perovskite crystal structures upon the photovoltaic properties and shows a pathway to achieve high VOC in perovskite PVCs under low-intensity ambient light sources.

Worldwide, catastrophic landslides are occurring as a result of abnormal climatic conditions. Since a landslide is caused by a combination of the triggers of rainfall and the vulnerability of spatial information, a study that can suggest a method to analyze the complex relationship between the two factors is required. In this study, the relationship between complex factors (rainfall period, accumulated rainfall, and spatial information characteristics) was designed as a system dynamics model as variables to check the possibility of occurrence of vulnerable areas according to the rainfall characteristics that change in real-time. In contrast to the current way of predicting the collapse time by analysing rainfall data, the developed model can set the precipitation period during rainfall. By setting the induced rainfall period, the researcher can then assess the susceptibility of the landslide-vulnerable area. Further, because the geospatial information features and rainfall data for the 672 h before the landslide's occurrence were combined, the results of the susceptibility analysis could be determined for each topographical characteristic according to the rainfall period and cumulative rainfall change. Third, by adjusting the General cumulative rainfall period (DG) and Inter-event time definition (IETD), the preceding rainfall period can be adjusted, and desired results can be obtained. An analysis method that can solve complex relationships can contribute to the prediction of landslide warning times and expected occurrence locations.

Obesity is closely associated with low-grade chronic and systemic inflammation and dyslipidemia, and the consumption of omega-3 polyunsaturated fatty acids (

Selective cleavage of C–C bonds can be a valuable tool for various applications including polymer degradation and biomass utilization. Performing chemical transformations involving C–C bond cleavag...

Various organic cations (e.g., methylammonium (MA+), butylammonium (BA+), formamidinium (FA+), etc.) have been studied and used in organometallic halide perovskite solar cells (PSCs). Most of the c...

The design and synthesis of a stable and efficient hole-transport material (HTM) for perovskite solar cells (PSCs) are one of the most demanding research areas. At present, 2,2′,7,7′-tetrakis[N,N-d...

Research and development of smart vessels has progressed significantly in recent years, and ships have become high-value technology-intensive resources. These ships entail high production costs and long-life cycles. Thus, modernized technical design, professional training, and aggressive maintenance are important factors in the efficient management of ships. With the continuing digital revolution, the industrial shipbuilding applicability of augmented reality (AR) and virtual reality (VR) technologies as well as related 3D system modeling and processes has increased. However, resolving the differences between AR/VR and real-world models remains burdensome. This problem is particularly evident when mapping various texture characteristics to virtual objects. To mitigate the burden and improve the performance of such technologies, it is necessary to directly define various texture characteristics or to express them using expensive equipment. The use of deep-learning-based CycleGAN, however, has gained attention as a method of learning and automatically mapping real-object textures. Thus, we seek to use CycleGAN to improve the immersive capacities of AR/VR models and to reduce production costs for shipbuilding. However, when applying CycleGAN’s textures to pipe structures, the performance is insufficient for direct application to industrial piping networks. Therefore, this study investigates an improved CycleGAN algorithm that can be specifically applied to the shipbuilding industry by combining a modified object-recognition algorithm with a double normalization method. Thus, we demonstrate that basic knowledge on the production of AR industrial pipe models can be applied to virtual models through machine learning to deliver low-cost and high-quality textures. Our results provide an on-ramp for future CycleGAN studies related to the shipbuilding industry.

As an essential component in efficient perovskite photovoltaics (PPVs), hole transport materials (HTMs) that meet the intricate requirements for next-generation charge transport layers have recently been of immense interest. Specifically, functionally tailored HTMs that aid in mitigating charge transport limitations and interfacial defects and thereby enhance the performance of both indoor and outdoor PPVs are being sought after. Herein, we developed a novel graft-type polymer composed of a benzo[1,2-b:4,5:b′]dithiophene-based main chain and poly(ethylene glycol) (PEG) side chains as an efficient dopant-free HTM for PPVs. Through a systemized tailoring of the contents of the side chains, we were able to control the hole transport and interfacial passivation abilities of the graft-type polymeric HTM. The polymeric HTM with an optimized PEG side chain exhibited a higher hole mobility, a reduced amount of interfacial traps, and an enhanced device stability compared to the control polymeric HTM. The PPVs capped with the optimized graft-type polymeric HTM demonstrated remarkably high power conversion efficiencies up to 38.2% and 21.7% under 1000 lux LED and AM 1.5 solar illuminations, respectively.

A Spiro fluorene-based dopant-free hole-transporting material denoted as Spiro-IA has been designed and developed from inexpensive starting materials with high yield via a simple synthetic approach for application in perovskite solar cells (PSCs). The unit cost of Spiro-IA can be as low as 1/9th that of the conventional Spiro-OMeTAD. Moreover, Spiro-IA shows good solubility in different organic solvents, e.g. CHCl3, acetone, EtOH, and DMF, and showed favorable charge-transport ability and greater photocurrent density compared to Spiro-OMeTAD. The UV absorption/emission spectra of Spiro-IA (λmax = 430 nm, Emax = 601 nm) are red shifted compared to those of Spiro-OMeTAD (λmax = 388 nm, Emax = 414 nm) with larger stokes shift values (171 nm) which helps suppress the loss of incident photons absorbed by the HTM and is more beneficial for improving the performance of PSCs. Optical and electrochemical studies show that Spiro-IA fulfilled the basic requirements of the hole transfer and electron regeneration process in the fabricated devices. PSCs fabricated (surface area = 1.02 cm2) with dopant-free Spiro-IA achieved a maximum power conversion efficiency (PCE) of 15.66% (JSC = 22.14 mA cm−2, VOC = 1.042 V, FF = 0.679%), which was comparable to that of the most commonly used Li-doped Spiro-OMeTAD (PCE = 15.93%, JSC = 20.37 mA cm−2, VOC = 1.057 V, FF = 0.74%) and surpassed that of the dopant-free Spiro-OMeTAD (PCE = 9.34%). Additionally, the PSCs based on dopant-free Spiro-IA achieved outstanding long-term stability and favorable conductivity (σ = 2.104 × 10−4 S cm−1) compared to those based on Spiro-OMeTAD (σ = 9.00 × 10−8 S cm−1). DFT studies were performed using Gaussian 09 at the B3LYP/6-31G (d/p) level to investigate their electron cloud delocalization in HOMO/LUMO levels. These results showed that Spiro-IA could be a promising candidate for low-cost PSC technology and has a great chance to supersede the expensive Spiro-OMeTAD.

Conventional, high-efficiency, hybrid organic–inorganic perovskites (e.g., methylammonium lead iodide (MAPbI3) and formamidinium lead iodide (FAPbI3)) having ammonium-based organic cations exhibit poor moisture stability mainly due to the effective hydrogen bonding interaction of nitrogen in the ammonium-based cations with water molecules. Recently, a sulfonium-based cation, trimethylsulfonium (TMS+), has attracted growing attention for the development of moisture-stable hybrid perovskite solar cells (PSCs). This research investigated the photovoltaic performance of trimethylsulfonium lead triiodide (TMSPbI3) based PSCs and their moisture stability both experimentally and theoretically. The results revealed that TMSPbI3 exhibited a relatively large optical band gap (Eg = 2.32 eV) and high absorption coefficient (α = 2.30 × 104 cm−1 at 500 nm) with a hexagonal one-dimensional crystal structure. The PSCs with a device structure of FTO/c-TiO2/m-TiO2/TMSPbI3/CuSCN/Au exhibited a power conversion efficiency (PCE) of 2.22% with no hysteresis in the I–V curve, and high moisture stability at ambient temperature (25 ± 3 °C, ca. 50% relative humidity) with a PCE loss of only ca. 4.6% after 500 h. This result could be attributed to the absence of the hydrogen bonding interaction of TMS+ with water molecules, leading to the effective stabilization of TMSPbI3 compared to MAPbI3 and FAPbI3, verified by density functional theory calculations.