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Magnetic microrobots and nanoparticles offer unique capabilities for medical applications by granting unprecedented access to intricate and delicate anatomical structures. Nevertheless, an intuitive manipulation approach remains a challenge due to their small size and limited feedback. This study presents a new method for magnetic microrobot and nanoparticle control that employs virtual reality (VR), creating an immersive and realistic view of the bodily anatomy and the microrobot within. This study compares three manipulation modes: a traditional mode using 2D displays, VR mode using a VR headset and touch controllers, and VR autonomous programmed maneuvering. It is shown that VR‐assisted modes reduce the manipulation time by improving spatial awareness. Nanoparticles in a VR environment are also manipulated. The proposed method will find applications in terms of intuitive, immersive microrobots or magnetic nanoparticle control in complex biological environments, thus in many medical procedures and for drug and cell delivery. The immersive nature of this approach enhances the ability of the user to perceive and understand complex anatomical structures, facilitating better navigation within delicate environments; both dexterity and spatial awareness are improved. Thus, it is shown how microrobots and magnetic nanoparticles can be controlled using immersive simulations to improve both visualization and manipulation.

Abstract All‐inorganic perovskite solar cells have shown great potential owing to their superior stability against thermal stress and moisture compared to organic–inorganic perovskite solar cells. However, there are some remaining issues in the all‐inorganic perovskite solar cell fabrication process, such as the low solubility of the perovskite precursors and the occurrence of the secondary phases. In this review, we focus on all‐inorganic CsPbBr3 perovskite solar cells and categorize them based on their fabrication process. Various processes and strategies that have been developed to solve the aforementioned issues including the general process of multistep spin coating are thoroughly investigated. Finally, a summary of the various processes for the all‐inorganic CsPbBr3 perovskite solar cells and an outlook for the development of highly efficient all‐inorganic perovskite solar cells are proposed.

Abstract Organometal halide perovskites are promising semiconducting materials for photodetectors because of their favorable optoelectrical properties. Although nanoscale perovskite materials such as quantum dots (QDs) show novel behavior, they have intrinsic stability issues. In this study, an effectively silane barrier‐capped quantum dot (QD@APDEMS) is thinly applied onto a bulk perovskite photosensitive layer for use in photodetectors. QD@APDEMS is synthesized with a silane ligand with hydrophobic CH3‐terminal groups, resulting in excellent dispersibility and durability to enable effective coating. The introduction of the QD@APDEMS layer results in the formation of a low‐defect perovskite film with enlarged grains. This is attributed to the grain boundary interconnection effect via interaction between the functional groups of QD@APDEMS and uncoordinated Pb2+ in grain boundaries. By passivating the grain boundaries, where various trap sites are distributed, hole charge‐carrier injection and shunt leakage can be suppressed. Also, from the energy point of view, the deep highest occupied molecular orbital (HOMO) level of QD@APDEMS can work as a hole charge injection barrier. Improved charge dynamics (generation, transfer, and recombination properties) and reduced trap density of QD@APDEMS are demonstrated. When this perovskite film is used in a photodetector, the device performance (especially the detectivity) stands out among existing perovskites evaluated for energy sensing device applications.

Abstract The development of new heterostructures with high photoactivity is a breakthrough for the limitation of solar‐driven water splitting. Here, we first introduce indium oxide (In2O3) nanorods (NRs) as a novel electron transport layer for bismuth vanadate (BiVO4) with a short charge diffusion length. In2O3 NRs reinforce the electron transport and hole blocking of BiVO4, surpassing the state‐of‐the‐art photoelectrochemical performances of BiVO4‐based photoanodes. Also, a tannin–nickel–iron complex (TANF) is used as an oxygen evolution catalyst to speed up the reaction kinetics. The final TANF/BiVO4/In2O3 NR photoanode generates photocurrent densities of 7.1 mA cm−2 in sulfite oxidation and 4.2 mA cm−2 in water oxidation at 1.23 V versus the reversible hydrogen electrode. Furthermore, the “artificial leaf,” which is a tandem cell with a perovskite/silicon solar cell, shows a solar‐to‐hydrogen conversion efficiency of 6.2% for unbiased solar water splitting. We reveal significant advances in the photoactivity of TANF/BiVO4/In2O3 NRs from the tailored nanostructure and band structure for charge dynamics.

Abstract The need for high‐resolution wind resource maps is increasing with the increase in the supply and development of wind power. Many physical downscaling models have been developed and applied to make these maps. However, as the existing models require extensive computations and time, statistical models with higher efficiency are being studied. Statistical models such as regression and machine learning models can quickly calculate wind resource maps, but they have a problem of low accuracy. This study proposes a machine learning model with new topography‐derived variables to interpret the physical characteristics of the wind. As the shape of topography, which was unable to be interpreted in previous studies, can be considered with new derived variables, a significant performance improvement was identified. The analysis was conducted using 1 km Weather Research and Forecasting (WRF) results and ERA5 reanalysis data from South Korea. Two Weibull distribution parameter maps were calculated and used as input and output data. Three collections of derived variables were devised and compared. Therefore, the multi‐resolution topography data showed the highest improvements with approximately 15% reduction in root mean square error (RMSE) for both the linear regression and machine learning models. In particular, the land area showed a decrease of 20%. The best proposed models showed an RMSE of 7% and 8% for two Weibull parameters. The results are expected to serve as a reference for continuing research and utilization of statistical models.

Abstract In the search for a more efficient solar cell, various types of tandem solar cells (TSCs) have been actively developed worldwide as the performances of the single junction solar cells approach their theoretical limits. Meanwhile, various materials and structures are adopted in TSCs, which makes their characterizations and comparison difficult. Along with the classical monolithic TSC, which exhibits two electrical contacts, devices with three or four electrical contacts have been widely studied as a more performing alternative of commercialized solar cells. For a fair and accurate evaluation of the device performance of TSCs, understanding the effectiveness and limitations of the characterization of the different types of TSCs is crucial. In this paper, we summarize various types of TSCs and discuss their characterization methods.

Abstract Tandem device architectures offer a route to greatly increase the maximum possible power conversion efficiencies (PCEs) of polymer solar cells, however, the complexity of tandem cell device fabrication (such as selecting bandgaps of the front and back cells, current matching, thickness, and recombination layer optimization) often result in lower PCEs than are observed in single‐junction devices. In this study, we analyze the influence of front cell and back cell bandgaps and use transfer matrix modeling to rationally design and optimize effective tandem solar cell structures before actual device fabrication. Our approach allows us to estimate tandem device parameters based on known absorption coefficients and open‐circuit voltages of different active layer materials and design devices without wasting valuable time and materials. Using this approach, we have investigated a series of wide bandgap, high voltage photovoltaic polymers as front cells in tandem devices with PTB7‐Th as a back cell. In this way, we have been able to demonstrate tandem devices with PCE of up to 12.8% with minimal consumption of valuable photoactive materials in tandem device optimization. This value represents one of the highest PCE values to date for fullerene‐based tandem solar cells.

Background. To analyze the microbiological causes of infectious endophthalmitis on an isolated island over ten years. Methods. A retrospective review of the medical records of 49 eyes clinically diagnosed with infectious endophthalmitis between January 2009 and December 2018 was done. The subjects were recruited from a single tertiary referral center on Jeju Island. The baseline characteristics of all subjects were investigated, and a culture examination was performed. The isolated pathogens were analyzed to determine how their microbiological features differed from those in regions with different geographical conditions. Results. Of the 49 eyes, causative microorganisms were identified in 27 eyes (55.1%). Bacteria were found in 24 cases and fungi in 3 cases. Among the exogenous causes, Staphylococcus species (Staphylococcus aureus, S. epidermidis, and S. hominis) were the most common pathogens (7 cases). Achromobacter xylosoxidans was the second most common causative pathogen (4 cases) followed by Moraxella species (3 cases). The most frequent endogenous origin was due to Klebsiella pneumoniae (6 cases). The subjects were divided into two groups according to the treatment results and analyzed for predisposing factors related to visual outcomes. The presence of diabetes mellitus (P = 0.038) and initial visual acuity (P ≤ 0.001) were significant predisposing factors for visual outcomes. Conclusion. The causative microorganisms of endogenous endophthalmitis on Jeju Island were not different from those reported previously. However, isolated exogenous microorganisms were different from those reported in other studies from inland areas. A high incidence and atypical clinical features of Achromobacter xylosoxidans and Moraxella in exogenous endophthalmitis were observed, reflective of the distinct climatic features of Jeju Island: high humidity and temperature. Therefore, considering the causative microorganisms of exogenous endophthalmitis, it may be assumed that the causative microorganisms of exogenous endophthalmitis and its clinical manifestations differ according to the region.

Purpose. To evaluate whether treatment with intravitreal corticosteroid and anti-vascular endothelial growth factor (VEGF) injections alternately can improve treatment outcomes of macular edema (ME) caused by retinal vein occlusion (RVO). Methods. This dual-center retrospective study included 112 eyes with treatment-naïve ME secondary to RVO that were alternately treated with intravitreal corticosteroid and anti-VEGF injections (33 eyes, alternate group) or treated only with intravitreal anti-VEGF injections (79 eyes, anti-VEGF group) on a pro re nata basis. Results. During the 12-month follow-up period, the alternate group achieved a visual acuity gain of 0.39 logMAR, while the anti-VEGF group achieved a gain of 0.21 logMAR (P=0.042). The alternate group demonstrated a reduction in the central macular thickness of 229.9-μm, while the anti-VEGF group achieved a reduction of 220.1 μm (P=0.887). The alternate group required an average of 5.2 injections, while the anti-VEGF received 4.2 injections (P

Rhegmatogenous retinal detachment (RRD) frequency was observed to be higher with an increase in the daily temperature range. This showed that a wide daily range of temperature, rather than the absolute value of the temperature, is associated with the occurrence of RRD. Purpose. To investigate the association between the frequency of rhegmatogenous retinal detachment (RRD) and the atmospheric temperature. Method. A retrospective review of consecutive eyes that had undergone primary RRD surgery from 1996 to 2016 at Chungbuk National University Hospital was conducted. Temperature data (highest, lowest, and mean daily temperatures and daily temperature range) in Chungbuk Province were obtained from the Korean Meteorological Administration database. We investigated the relationship between the daily temperature range and the frequency of RRD surgery. We also analyzed the association between various temperature data and the frequency of RRD surgery. Result. There were 1,394 RRD surgeries from 1996 to 2016. Among them, 974 eyes were included in this study. The monthly average number of RRD operations showed a bimodal peak (in April and October) throughout the year. With the same tendency as the frequency of RRD, the monthly average of the daily temperature range over 1 year also showed a bimodal peak in April and October. There was a significant positive correlation between the monthly average of the daily temperature range and the number of RRD surgeries (r = 0.297, P

Purpose. To investigate the effectiveness of mineralocorticoid receptor (MR) antagonist in patients with steroid-induced central serous chorioretinopathy (CSC). Methods. A retrospective review was conducted of steroid-induced CSC patients who were treated with the MR antagonist spironolactone 50 mg once per day for at least 1 month. The primary outcome measure was complete resolution rate of subretinal fluid (SRF) after spironolactone treatment. Secondary outcomes included central subfield thickness (CST), subfoveal choroidal thickness (SFCT), and best-corrected visual acuity (BCVA) changes after spironolactone treatment. Results. Seventeen eyes from 15 patients were included in this study. Conditions warranting chronic systemic steroid use were myasthenia gravis (6/15, 40%), glomerulonephritis (5/15, 33.3%), and organ transplantation (4/15, 26.7%). Mean symptom duration of CSC was 4.00 ± 3.04 months. After spironolactone treatment, 14 eyes (82.4%) showed complete resolution of SRF (P

Demand response (DR) is a major contributor to grid stabilization during peak times. As the scope and functions of DR increase, DR participation of residential customers has attracted great attention. The main issue of DR design for the residential sector is to build an integrated network for exchange of DR signals between the utility operator and home users who want to participate in DR services at various locations. In this paper, we introduce an automated residential DR model based on advanced metering infrastructure (AMI) network. The internationally recognized standard protocol, known as the open automated demand response version 2.0 (OpenADR 2.0), is applied to realize a fully automated DR (ADR). In order to utilize existing AMI devices as ADR resources, the smart meter is modified while retaining current structure and functions, and various ADR devices are developed based on OpenADR 2.0 protocol. Simulation and demonstration tests are conducted to confirm conformance of the protocol and to verify load variations of home appliances under our ADR model. The developed software programs have obtained an international certification from the OpenADR Alliance.