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We investigated how the positional arrangement of electron-donating (amino) and electron-withdrawing (ester) groups in single benzene-based fluorophores influences their emission properties. By synthesizing 26 regioisomeric fluorophores, we achieved wavelength modulation from 322 to 539 nm, revealing key correlations between functional group positioning and photophysical behavior. [ABSTRACT FROM AUTHOR]

Introducing two electron-donating groups and two electron-withdrawing groups together in symmetrical positions on the benzene ring is a fundamental way to synthesize and prepare single-benzene-based fluorophores (SBBFs). Their photophysical properties are adjusted through the electronic and structural properties of the functional groups. Reported herein is the functionalization of diaminobenzene derivatives with various amine protecting groups, including amides, urea, carbamates, and sulfonamides. Both absorption and emission properties of the obtained SBBF molecules were carefully investigated. Sequential and unsymmetric diamine protections were also explored with diaminobenzene derivatives for fine-tuning of the molecular properties. [ABSTRACT FROM AUTHOR]

Single‐ion conducting (SIC) polymers, wherein anions are covalently bonded to the polymer chain, selectively facilitate the movement of lithium ions, making them promising polymer electrolytes for lithium‐ion batteries because only lithium ion acts as a charge carrier. Carboxylate‐type SIC polymers offer cost advantages and are facilely prepared compared to conventional types like sulfonylamide‐type SIC polymers. However, they are known to suffer from inefficient dissociation of lithium ions due to their high basicity. In this study, enhancement of lithium‐ion dissociation in carboxylate‐type SIC polymers is investigated by complexing them with ionic liquid (IL). Incorporation of IL with the SIC polymer significantly improves electrochemical properties, achieving a high ionic conductivity close to 2 mS cm−1 and a critical current density of 2.1 mA cm−2 in a Li symmetric cell at 25 °C. The interaction between the SIC polymer and IL is confirmed through infrared and Raman spectroscopy. Electrochemical tests of the Li/LiFePO4 cell exhibit a high reversible capacity of 128.6 mAh g−1 with a cycle retention of 89.9 % after 100 cycles at 1 C (1 C=170 mA g−1) and an excellent recuperation even after rate tests at 6 C. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) systems have been widely adopted for full autonomy in various fields due to their convenience. However, changes in the air gap between the Tx and Rx coils significantly affect efficiency. To overcome this challenge, this paper introduces the determination of a compensation capacitor for a distance-variable WPT system that is robust in varying air gap conditions. The proposed method was verified using theoretical analysis, simulation, and experimental measurement. The electrical circuit was modeled using a T-equivalent model in a series–series (SS) topology to calculate power transfer efficiency (PTE). Specifically, compensation capacitors were analyzed at distances of 10, 30, and 50 mm, considering different self-inductance values. These results are compared against varying load resistances to demonstrate the effectiveness of the proposed approach. Additionally, the PTE drop ratio was defined to facilitate comparison. The results show that the PTE drop ratio for the compensation capacitor at the farthest distance was consistently smaller than that for the capacitor at the nearest distance under varying air gaps and load resistances. In this research, the difference in the PTE drop ratio between 10 and 50 mm was measured, demonstrating that determining the capacitor at the farthest distance reduces the PTE drop ratio across a range of operational conditions. [ABSTRACT FROM AUTHOR]

Drone operation, a new driving force for logistics innovation, is struggling to overcome practical challenges. One of the concerns for drone utilization is limited flight ranges, and different concepts of facilities are continually developed to support drone delivery. These new facilities prompt the need to integrate decision‐making across different phases. In particular, the deployment of facilities that complement the physical limitations of drones and the scheduling of drones to perform delivery tasks are closely related. Therefore, we developed a scheduling‐location problem with drones, a new methodology for integrating operational and strategic planning decisions. The integrated decision‐making determines the location of the drone facilities by not only considering the critical distance of facilities but also by taking into account whether the delivery schedule is implemented. In our model, additional drone facilities are sometimes opened considering available drones due to the feasibility of the delivery schedule. An extended formulation and a restricted master heuristic are proposed to solve problems time‐efficiently. Computational results show that the restricted master heuristic outperforms the mathematical model in finding solutions for large‐scale instances. The developed model and heuristic algorithm provide drone delivery services even in areas that are not easily reachable by drones due to being located far from the warehouse and can be effectively applied to humanitarian logistics. [ABSTRACT FROM AUTHOR]

The Zika virus has been shown to infect glioblastoma stem cells via the membrane receptor α v β 5 , which is activated by the stem-specific transcription factor SOX2. Since the expression level of SOX2 is an important predictive marker for successful virotherapy, it is important to understand the fundamental mechanisms of the role of SOX2 in the dynamics of cancer stem cells and Zika viruses. In this paper, we develop a mathematical ODE model to investigate the effects of SOX2 expression levels on Zika virotherapy against glioblastoma stem cells. Our study aimed to identify the conditions under which SOX2 expression level, viral infection, and replication can reduce or eradicate the glioblastoma stem cells. Analytic work on the existence and stability conditions of equilibrium points with respect to the basic reproduction number are provided. Numerical results were in good agreement with analytic solutions. Our results show that critical threshold levels of both SOX2 and viral replication, which change the stability of equilibrium points through population dynamics such as transcritical and Hopf bifurcations, were observed. These critical thresholds provide the optimal conditions for SOX2 expression levels and viral bursting sizes to enhance therapeutic efficacy of Zika virotherapy against glioblastoma stem cells. This study provides critical insights into optimizing Zika virus-based treatment for glioblastoma by highlighting the essential role of SOX2 in viral infection and replication. [ABSTRACT FROM AUTHOR]

We herein report a fundamental mechanistic investigation into photochemical metal‐nitrenoid generation and inner‐sphere transposition reactivity using organometallic photoprecursors. By designing Cp*Ir(hydroxamate)(Ar) complexes, we induced photo‐initiated ligand activation, allowing us to explore the amidative σ(Ir–aryl) migration reactivity. A combination of experimental mechanistic studies, femtosecond transient absorption spectroscopy, and density functional theory (DFT) calculations revealed that the metal‐to‐ligand charge transfer enables the σ(N−O) cleavage, followed by Ir‐acylnitrenoid generation. The final inner‐sphere σ(Ir–aryl) group migration results in a net amidative group transposition. [ABSTRACT FROM AUTHOR]

We herein report a fundamental mechanistic investigation into photochemical metal‐nitrenoid generation and inner‐sphere transposition reactivity using organometallic photoprecursors. By designing Cp*Ir(hydroxamate)(Ar) complexes, we induced photo‐initiated ligand activation, allowing us to explore the amidative σ(Ir–aryl) migration reactivity. A combination of experimental mechanistic studies, femtosecond transient absorption spectroscopy, and density functional theory (DFT) calculations revealed that the metal‐to‐ligand charge transfer enables the σ(N−O) cleavage, followed by Ir‐acylnitrenoid generation. The final inner‐sphere σ(Ir–aryl) group migration results in a net amidative group transposition. [ABSTRACT FROM AUTHOR]

The widespread acceptance of robotic surgery is extending to oral procedures. The demand for minimally invasive techniques is driving research into the cosmetic and oncologic benefits of robotic neck surgery. This study used propensity score matching to analyze the clinical course and postoperative outcomes of robot-assisted neck dissections for oncologic efficacy and surgical safety. Between May 2020 and April 2024, 200 OSCC patients underwent surgery and 42 were excluded. The cohort included 158 patients, 128 of whom underwent unilateral neck dissection and 30 of whom underwent bilateral neck dissection. Robotic-assisted neck dissection (RAND) was performed in 36 patients while conventional transcervical neck dissection (CTND) was performed in 122 patients. Data analysis included several factors, including lymph node retrieval and perioperative outcomes, with 1:1 propensity score matching to ensure fairness. Each of the 39 neck specimens with 36 patients was selected. The CTND group was 8 years older overall than the RAND group, but otherwise similar in terms of primary site and clinical stage. The RAND group had a 55-min longer operative time and 140 cc more hemovac drainage than the CTND group, but the hospital stay and intensive care unit duration were the same, and the number of lymph nodes retrieved was the same. Survival rates also showed no difference across all stages. This shows that RAND is in no way inferior to CTND in terms of perioperative or oncologic outcomes, and demonstrates the safety of robot-assisted surgery, even in patients who require flaps or in patients with advanced stages. [ABSTRACT FROM AUTHOR]

A strategic approach to develop efficient ultra‐broadband terahertz (THz) crystals involves the incorporation of different electron donating groups (EDGs) into cationic chromophores. In contrast to the widely utilized non‐cyclic 4‐(dimethylamino)phenyl (DA) EDG, cyclic 5‐membered 4‐(2‐(hydroxymethyl)pyrrolidine‐1‐yl)phenyl (PB) and cyclic 6‐membered 4‐(3‐(hydroxymethyl)piperidin‐1‐yl)phenyl (PN) EDGs exhibit an asymmetrical shape with a strongly interacting hydroxymethyl group at the chiral center. Notably, the PB EDG shows narrower intrinsic vibrational states with lower conformational flexibility and smaller ring flips compared to the PN EDG. In the crystalline state, introducing the PB EDG leads to the formation of a new class of nonlinear optical assembly, the so‐called stair‐type cation‐anion assembly. This assembly demonstrates optimal chromophore alignment with state‐of‐the‐art effective first hyperpolarizability (209 × 10−30 esu). Furthermore, the PB EDG‐based crystals exhibit significantly lower THz absorption compared to previously reported benchmark crystals. In THz wave generation experiments, PB EDG‐based crystals demonstrate state‐of‐the‐art efficiency and ultrabroad spectral bandwidth, featuring a cut‐off frequency of up to 16 THz. [ABSTRACT FROM AUTHOR]

Heat waves are natural disasters that can result in large numbers of casualties. The frequency and damage caused by heat waves have been increasing in Korea due to climate change. The regional impacts of heat waves can vary according to environmental and socioeconomic factors regardless of duration and intensity. This study assessed the risks posed by heat waves for administrative districts in Korea according to climate change scenarios and the risk assessment framework of Fifth Assessment Report presented by the Intergovernmental Panel on Climate Change. The risk of heat waves is usually based on a combination of hazard, exposure, and vulnerability. Unlike previous studies using subjective weights, this study employed partial least squares—structural equation modeling (PLS-SEM) and entropy weighting, which are more objective methods of determining the indicators and weights, to estimate the exposure and vulnerability of heat waves. The results showed that at least 40% and 46% of administrative districts are expected to experience a high level of risk according to the representative concentration pathway scenarios, i.e., RCP 4.5 and 8.5, respectively. In addition, significant differences were observed in the heat wave risks calculated in this study for the upper and lower regions, with respect to cumulative heat-related morbidity rates, whereas the heat wave risk reported by the Korean Ministry of Environment was found to be insignificant. The results of this study can be used to prepare for heat waves and minimize damage caused by them. [ABSTRACT FROM AUTHOR]

The symmetry reduction of molecular shape of cationic chromophores as a design strategy to develop organic terahertz (THz) generators is used. Electron donating group (EDG) with an asymmetric shape is introduced into two types of cationic styryl‐quinolinium chromophores, leading to the development of several novel non‐centrosymmetric crystals with high macroscopic optical nonlinearity. In contrast, when an EDG with a symmetric shape is introduced, centrosymmetric crystal structure is obtained in all investigated crystals. For THz wave generation, crystals based on asymmetrically shaped EDG exhibit several optimal crystal characteristics, including a plate‐shape morphology, a large size, and an in‐plane polar axis. Furthermore, over the entire range of molecular phonon vibrations, 0.5–4 THz, the steric hindrance group in the asymmetrically shaped EDG has a strong influence on the suppression of THz phonon vibrations, leading to a low THz absorption coefficient. The crystals based on asymmetrically shaped EDG generate an ≈40 times stronger THz electric field than the inorganic ZnTe crystal and very broad THz spectra, extending up to 16 THz. Thus, the symmetry reduction of the molecular shape of cationic chromophores through the introduction of an asymmetrically shaped EDG is an effective design approach for the development of novel organic THz crystals. [ABSTRACT FROM AUTHOR]

Background: Iatrogenic mandibular nerve damage resulting from oral surgeries and dental procedures is painful and a formidable challenge for patients and oral surgeons alike, mainly because the absence of objective and quantitative methods for diagnosing nerve damage renders treatment and compensation ambiguous while often leading to medico-legal disputes. The aim of this study was to examine discriminating factors of traumatic mandibular nerve within a specific magnetic resonance imaging (MRI) protocol and to suggest tangible diagnostic criteria for peripheral trigeminal nerve injury. Methods: Twenty-six patients with ipsilateral mandibular nerve trauma underwent T2 Flex water, 3D short tau inversion recovery (STIR), and diffusion-weighted imaging (DWI) acquired by periodically rotating overlapping parallel lines with enhanced reconstruction (PROPELLER) pulse sequences; 26 injured nerves were thus compared with contra-lateral healthy nerves at anatomically corresponding sites. T2 Flex apparent signal to noise ratio (FSNR), T2 Flex apparent nerve-muscle contrast to noise ratio (FNMCNR) 3D STIR apparent signal to noise ratio (SSNR), 3D STIR apparent nerve-muscle contrast to noise ratio (SNMCNR), apparent diffusion coefficient (ADC) and area of cross-sectional nerve (Area) were evaluated. Results: Mixed model analysis revealed FSNR and FNMCNR to be the dual discriminators for traumatized mandibular nerve (p < 0.05). Diagnostic performance of both parameters was also determined with area under the receiver operating characteristic curve (AUC for FSNR = 0.712; 95% confidence interval [CI]: 0.5660, 0.8571 / AUC for FNMCNR = 0.7056; 95% confidence interval [CI]: 1.011, 1.112). Conclusions: An increase in FSNR and FNMCNR within our MRI sequence seems to be accurate indicators of the presence of traumatic nerve. This prospective study may serve as a foundation for sophisticated model diagnosing trigeminal nerve trauma within large patient cohorts. [ABSTRACT FROM AUTHOR]

The development of site‐selective functionalization of N‐heteroarenes is highly desirable in streamlined synthesis. In this context, direct amination of pyridines stands as an important synthetic methodology, with particular emphasis on accessing 4‐aminopyridines, a versatile pharmacophore in medicinal chemistry. Herein, we report a reaction manifold for the C4‐selective amination of pyridines by employing nucleophilic substitution of hydrogen (SNH). Through 4‐pyridyl pyridinium salt intermediates, 4‐aminopyridine products are obtained in reaction with aqueous ammonia without intermediate isolation. The notable regioselectivity was achieved by the electronic tuning of the external pyridine reagents along with the maximization of polarizability in the proton elimination stage. Further mechanistic investigations provided a guiding principle for the selective C−H pyridination of additional N‐heteroarenes, presenting a strategic avenue for installation of diverse functional groups. [ABSTRACT FROM AUTHOR]

The development of site‐selective functionalization of N‐heteroarenes is highly desirable in streamlined synthesis. In this context, direct amination of pyridines stands as an important synthetic methodology, with particular emphasis on accessing 4‐aminopyridines, a versatile pharmacophore in medicinal chemistry. Herein, we report a reaction manifold for the C4‐selective amination of pyridines by employing nucleophilic substitution of hydrogen (SNH). Through 4‐pyridyl pyridinium salt intermediates, 4‐aminopyridine products are obtained in reaction with aqueous ammonia without intermediate isolation. The notable regioselectivity was achieved by the electronic tuning of the external pyridine reagents along with the maximization of polarizability in the proton elimination stage. Further mechanistic investigations provided a guiding principle for the selective C−H pyridination of additional N‐heteroarenes, presenting a strategic avenue for installation of diverse functional groups. [ABSTRACT FROM AUTHOR]

A high-infrared (IR) emissivity is required to dissipate heat effectively from high-temperature surfaces even in a near-vacuum environment. This radiative cooling capability is essential for the emissive layer of EUV pellicles operating under high vacuum conditions with increasing EUV source powers to ensure thermomechanical stability. We compute the IR emissivity of metal films by combining the classical oscillator model and DFT calculations. Based on the calculations, we predict a positive correlation between the electrical resistivity and IR emissivity of metal films, which is consistent with a recent experiment on Ru thin films. Our findings can provide a practical indicator for achieving high IR emissivity of metallic thin films based on electrical measurements. This emissivity–resistivity correlation can provide an effective way to search a large material space, and choose and synthesize a highly emissive layer of EUV pellicles. In this study, we computed the infrared absorbance of Ru thin films through the integration of the classical Drude-Lorentz oscillator model and DFT calculations. According to the Kirchhoff's law of thermal radiation, the IR absorbance is equal to the IR emittance. Based on the calculated results, we propose a positive correlation between IR emissivity and electrical resistivity. [ABSTRACT FROM AUTHOR]

Background: Hematopoietic stem cells (HSCs) and multipotent progenitors (MPPs) play a pivotal role in maintaining lifelong hematopoiesis. The distinction between stem cells and other progenitors, as well as the assessment of their functions, has long been a central focus in stem cell research. In recent years, deep learning has emerged as a powerful tool for cell image analysis and classification/prediction. Methods: In this study, we explored the feasibility of employing deep learning techniques to differentiate murine HSCs and MPPs based solely on their morphology, as observed through light microscopy (DIC) images. Results: After rigorous training and validation using extensive image datasets, we successfully developed a three-class classifier, referred to as the LSM model, capable of reliably distinguishing long-term HSCs, short-term HSCs, and MPPs. The LSM model extracts intrinsic morphological features unique to different cell types, irrespective of the methods used for cell identification and isolation, such as surface markers or intracellular GFP markers. Furthermore, employing the same deep learning framework, we created a two-class classifier that effectively discriminates between aged HSCs and young HSCs. This discovery is particularly significant as both cell types share identical surface markers yet serve distinct functions. This classifier holds the potential to offer a novel, rapid, and efficient means of assessing the functional states of HSCs, thus obviating the need for time-consuming transplantation experiments. Conclusion: Our study represents the pioneering use of deep learning to differentiate HSCs and MPPs under steady-state conditions. This novel and robust deep learning-based platform will provide a basis for the future development of a new generation stem cell identification and separation system. It may also provide new insight into the molecular mechanisms underlying stem cell self-renewal. [ABSTRACT FROM AUTHOR]

When dementia is diagnosed, it is most often already past the point of irreversible neuronal deterioration. Neuropsychological tests are frequently used in clinical settings; however, they must be administered properly and are oftentimes conducted after cognitive impairment becomes apparent or is raised as a concern by the patient or a family member. It would be beneficial to develop a non-invasive system for approximating cognitive scores which can be utilized by a general practitioner without the need for cognitive testing. To this end, gait, visual, auditory, postural, and olfactory function parameters, reported history of illness, and personal habits were used to train an elastic-net regression model in predicting the cognitive score. Community-dwelling men (N = 104) above the age of sixty-five participated in the current study. Both individual variables and principal components of the motor and sensory functions were included in the elastic-net regression model, which was trained on 70% of the dataset. The years of education, limits of stability testing time, regular ophthalmological exams, postural testing time principal component, better ear score on the sentence recognition test, and olfactory discrimination score largely contributed to explaining over 40% of the variance in the cognitive score. [ABSTRACT FROM AUTHOR]

Since the third wave of democratization, specialized constitutional courts have spread widely across developed and developing countries and become key to government accountability, rights protection, and cross-institutional conflict resolution. Simultaneously, nearly half of all constitutional court adoptions have occurred in Europe. What explains the global, yet Eurocentric, spread of constitutional courts? Countries' institutional endowments, particularly domestic and international legal institutions, are key to this crucial choice of constitutional design. Common law countries are less likely to establish specialized constitutional courts than their civil law counterparts due to their domestic legal system's relatively weaker affinity with the constitutional court model. Furthermore, the Council of Europe's Venice Commission—the main international organization specifically promoting constitutional courts—has catalyzed their wide and rapid spread especially, but not exclusively, in Europe. Our theory gains robust support from event history analyses of 172 developed and developing countries from 1947 to 2019. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effect of temperature and time of sous-vide cooking method on the characteristics of Thoroughbred horse loin. Sliced portions (200 ± 50 g) were cooked by boiling (control) and sous-vide (65 and 70 °C for 12, 18, and 24 h). The samples were analyzed for proximate composition, pH, color, texture, microstructure, sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE), microbiology, volatile organic compounds (VOCs), nucleotide content, and fatty acids composition. The color analysis showed decreased redness at elevated temperatures. Improved tenderness, demonstrated by reduced shear force values (36.36 N at 65 °C for 24 h and 35.70 N at 70 °C for 24 h). The micrographs indicated dense fiber arrangements at 70 °C. The SDS-PAGE revealed muscle protein degradation with extended sous-vide cooking. The VOC analysis identified specific compounds, potentially distinctive markers for sous-vide cooking of horse meat including 1-octen-3-ol, decanal, n-caproic acid vinyl ester, cyclotetrasiloxane, octamethyl, and 3,3-dimethyl-1,2-epoxybutane. This study highlights the cooking time's primary role in sous vide-cooked horse meat tenderness and proposes specific VOCs as potential markers. Further research should explore the exclusivity of these VOCs to sous-vide cooking. [ABSTRACT FROM AUTHOR]

Wireless Power Transfer (WPT) systems are widely used today across various applications. Due to their interoperability, there are many instances where the receiver can vary, and consequently, the air gap may differ depending on the application. In such distance-variable WPT systems, the self-inductance of the transmitting and receiving coils can change, which means that zero-voltage switching (ZVS) is not always guaranteed. In this paper, we propose a method to determine the matching capacitor that is sufficient to ensure ZVS in a distance-variable system. According to our theoretical approach, the matching capacitance should be determined for the farthest air gap. The proposed idea was verified through experiments, and the results demonstrate that the ZVS is guaranteed within the specified range of variable distances. [ABSTRACT FROM AUTHOR]

We report a transition metal-catalyzed ring expansion of azulene that can be contrasted with C–H functionalization. This study represents the first example of the successful ring expansion of azulene using Cu(hfacac)2 (hfacac: hexafluoroacetylacetonate) with a diazo reagent. This result is notable for extending the Buchner reaction, previously limited to benzenoid aromatics, to nonbenzenoid compounds. The chemoselectivity of the reaction can be directed towards C–H functionalization by substituting the Cu catalyst with AgOTf. This approach does not require the addition of phosphine, NHC, or related ligands, and prefunctionalization of azulenes is unnecessary. Furthermore, the method exhibits excellent functional group tolerance, allowing for the synthesis of a wide range of 6,7-bicyclic compounds and C–H functionalized azulenes. We also present a theoretical study that explains the experimental observations, explaining why copper afford the ring expansion product while silver forms the C–H alkylation product. Fused carbocycles are key structural elements of molecules in nature and they are often found in drugs and organic materials, but bicyclic systems containing six and seven-membered rings are difficult to prepare. Here, the authors functionalize an azulene skeleton that consists of fused five and seven-membered rings and carry out a ring expansion reaction to afford the desired bicycles. [ABSTRACT FROM AUTHOR]

Understanding nonradiative transition mechanisms is important in various situations. However, compared with radiative processes where temporal profiles of photon emission can be monitored in a straightforward manner, experimentally accessing the rate information may not be an easy task with nonradiative transitions. Hence, applying theoretical tools toward predicting the rates can be a useful tactic. Such predictions become very useful in designing optoelectronic materials as in the molecules adopted for constructing organic light‐emitting diodes (OLEDs). The correlation function formalism is a method that can fulfill the purpose of designing OLED materials. The formalism requires information regarding the vibrational normal modes of the two electronic states before and after the transition. Because the method is also based on harmonic oscillator approximation, it can actually fail to provide high reliability when there is a large geometric distortion between the initial and the final states. In fact, the harmonic normal mode picture is more prone to lose reliability in the Cartesian coordinates than in the internal ones even at a small distortion, and hence adopting internal coordinates may be more preferable for practical calculations. This is because normal mode mixing becomes less severe when molecular coordinates are described with internal degrees of freedom such as bond stretching, bending, and torsion. In this regard, how much more reliable the nonradiative rate predictions in OLED materials become with the use of internal coordinate system deserves a close inspection. In this account, we review on the derivation of the correlation function formalism and provide how it can be adapted toward the use of the internal coordinates. As a demonstration, we evaluate the intersystem crossing and the internal conversion rates of a series of thermally activated delayed fluorescence (TADF) molecules with both Cartesian and internal coordinate systems. Overall, handling transitions involving substantial structural changes is improved indeed with the internal coordinates. However, limitations are still apparent for the TADF systems with a flexible donor–acceptor type construct especially when the inevitable inter‐domain twisting takes place with the electronic transition. Future prospect for handling the issue is commented as a concluding remark. [ABSTRACT FROM AUTHOR]

The density of donor-like state distributions in solution-processed indium–zinc-oxide (IZO) thin-film transistors (TFTs) is thoroughly analyzed using photon energy irradiation. This study focuses on quantitatively calculating the distribution of density of states (DOS) in IZO semiconductors, with a specific emphasis on their variation with indium concentration. Two calculation methods, namely photoexcited charge collection spectroscopy (PECCS) and photocurrent-induced DOS spectroscopy (PIDS), are employed to estimate the density of the donor-like states. This dual approach not only ensures the accuracy of the findings but also provides a comprehensive perspective on the properties of semiconductors. The results reveal a consistent characteristic: the Recombination–Generation (R-G) center energy ET, a key aspect of the donor-like state, is acquired at approximately 3.26 eV, irrespective of the In concentration. This finding suggests that weak bonds and oxygen vacancies within the Zn-O bonding structure of IZO semiconductors act as the primary source of R-G centers, contributing to the donor-like state distribution. By highlighting this fundamental aspect of IZO semiconductors, this study enhances our understanding of their charge-transport mechanisms. Moreover, it offers valuable insight for addressing stability issues such as negative bias illumination stress, potentially leading to the improved performance and reliability of solution-processed IZO TFTs. The study contributes to the advancement of displays and technologies by presenting further innovations and applications for evaluating the fundamentals of semiconductors. [ABSTRACT FROM AUTHOR]

An external tendon failure of the PSC box girder was found due to corrosion in South Korea, and the maintenance authorities promoted a study on evaluation and maintenance methods. One of their concerns was to confirm that the tendons were constantly available through repair when voids or minor corrosion were found in ducts. This study, thus, conducted external tendon experiments with insufficient grout filling and corrosion, and the resulting decrease in deterioration behaviours was investigated. The corrosion was accelerated during the experiment, and the strains and prestressing force were measured. The test results indicated minimal reductions in prestressing force and strain as the corrosion was induced, followed by significant fluctuations when a corroded wire ruptured. Prior to the rupture, the strain development was approximately 130 µε. However, after the rupture, the strain increased significantly, reaching a maximum of 4,296 µε in compression and 2,776 µε in tension. It was also confirmed that enough grout ratio to strands resulted in meaningful stress redistribution among the strands and that the wire rupture caused various strain development due to impact load. Based on the test result, a method for corrosion monitoring after re-grout was also proposed using low-power sensing and strain gauges. [ABSTRACT FROM AUTHOR]

Terahertz (THz) waves interact with molecular phonon vibrations of organic matter. When designing organic THz‐device materials, conformational flexible groups (CFGs) are in most cases avoided. CFGs create many low‐energy conformers with high conformational entropy, which results in large and many phonon vibration modes that lead to undesired self‐absorption of THz waves. Here, nonpolar CFGs only having weak intermolecular interaction capability are unusually introduced into organic THz‐device materials, utilized for efficient THz wave generation. Newly designed THz‐source crystals possess nonpolar methylene (CH2)n units having high conformational flexibility. Compared to previously reported benchmark crystals without methylene CFGs, introducing methylene CFGs significantly reduces void volume in newly designed crystals. This leads to the suppression of molecular phonon vibrations below 2.0 THz (i.e., introducing flexibility results in local rigidity). At infrared pump wavelengths, new CFG‐contained crystals generate a strong THz electric field that is one order of magnitude stronger than that generated in inorganic ZnTe crystals. CFG‐contained crystals exhibit a flatter spectral shape of the generated THz wave than benchmark crystals without methylene CFGs. Therefore, the introduction of CFGs is a very intriguing design strategy for organic THz‐device materials to reduce the limitations caused by phonon vibrations. [ABSTRACT FROM AUTHOR]

The aerodynamics of a floating wind turbine was analyzed, and the results were applied to a wake model by introducing a modified NOJ model. In addition, the effect of the 6-DOFs characteristics on the wind farm optimization is examined by comparing the platform type (fixed and floating) and wake models (NOJ model and modified NOJ model). The unsteady vortex-lattice method (UVLM) is used to analyze the aerodynamic characteristics of a floating wind turbine. The relationship between the 6-DOFs motion and power performance is validated through theoretical analysis. This study proposes a modified NOJ model to consider the multiwake effect of a floating wind farm. The results demonstrate that the conventional layout optimization method has an error in the layout position and power performance due to the characteristics of a floating wind turbine. Therefore, 6-DOFs motion and its influence should be considered for accurate floating wind farm optimization. [ABSTRACT FROM AUTHOR]

Impairments in gait, postural stability, and sensory functions were proved to be strongly associated with severe cognitive impairment such as in dementia. However, to prevent dementia, it is necessary to detect cognitive deterioration early, which requires a deeper understanding of the connections between the aforementioned functions and global cognition. Therefore, the current study measured gait, postural, auditory, and visual functions and, using principal component analysis, explored their individual and cumulative association with global cognition. The global cognitive function of 82 older Korean males was determined using the Montreal Cognitive Assessment. The motor and sensory functions were summarized into seven independent factors using factor analysis, followed by age and education-level-adjusted linear regression model analysis. The seven factors obtained using factor analysis were gait speed, gait stability, midstance, general auditory ability, auditory recognition, overall visual ability, and postural stability. The linear regression model included years of education, gait stability, postural stability, and auditory recognition, and was able to explain more than half of the variability in cognitive score. This shows that motor and sensory parameters, which are obtainable through wearable sensors and mobile applications, could be utilized in detecting cognitive fluctuations even in the early stages of cognitive deterioration. [ABSTRACT FROM AUTHOR]

Although some surgeons prefer anterolateral thigh and latissimus dorsi flap for soft tissue reconstruction in the head and neck area because it minimizes donor site complications, the radial forearm flap remains the workhorse for soft tissue reconstruction due to its reliability. To reduce donor site morbidity, the authors developed a novel technique for radial forearm flap harvesting using a robotic device. 42 radial forearm free flap reconstruction cases were studied, consisting of 31 conventional and 11 robot-assisted cases. 1:1 propensity score matching was done according to age, sex, previous and postoperative radiation therapy history and method used for vein anastomosis. There was no significant difference in flap outcome, which was 100% vitality in the robot-assisted group and 90.9% vitality in the conventional group. The robot-assisted group showed significantly longer mean harvesting time than did the conventional group, being 107.2 min and 67.0 min, respectively. Robot-assisted radial forearm flap harvesting can reduce donor site complications by minimizing incision. When more surgical experience is gained under appropriate case selection, we expect our robot-assisted method will yield a harvesting time similar to that of the conventional method and thus become more reliable and feasible. [ABSTRACT FROM AUTHOR]

Understanding the density of state (DOS) distribution in solution-processed indium-zinc-oxide (IZO) thin-film transistors (TFTs) is crucial for addressing electrical instability. This paper presents quantitative calculations of the acceptor-like state distribution of solution-processed IZO TFTs using thermal energy analysis. To extract the acceptor-like state distribution, the electrical characteristics of IZO TFTs with various In molarity ratios were analyzed with respect to temperature. An Arrhenius plot was used to determine electrical parameters such as the activation energy, flat band energy, and flat band voltage. Two calculation methods, the simplified charge approximation and the Meyer–Neldel (MN) rule-based carrier–surface potential field-effect analysis, were proposed to estimate the acceptor-like state distribution. The simplified charge approximation established the modeling of acceptor-like states using the charge–voltage relationship. The MN rule-based field-effect analysis validated the DOS distribution through the carrier–surface potential relationship. In addition, this study introduces practical and effective approaches for determining the DOS distribution of solution-processed IZO semiconductors based on the In molarity ratio. The profiles of the acceptor-like state distribution provide insights into the electrical behavior depending on the doping concentration of the solution-processed IZO semiconductors. [ABSTRACT FROM AUTHOR]

Triplet harvesting processes are essential for enhancing efficiencies of fluorescent organic light-emitting diodes. Besides more conventional thermally activated delayed fluorescence and triplet-triplet annihilation, the hot exciton mechanism has been recently noticed because it helps reduce the efficiency roll-off and improve device stability. Hot exciton materials enable the conversion of triplet excitons to singlet ones via reverse inter-system crossing from high-lying triplet states and thereby the depopulation of long-lived triplet excitons that are prone to chemical and/or efficiency degradation. Although their anti-Kasha characteristics have not been clearly explained, numerous molecules with behaviors assigned to the hot exciton mechanism have been reported. Indeed, the related developments appear to have just passed the stage of infancy now, and there will likely be more roles that computational elucidations can play. With this perspective in mind, we review some selected experimental studies on the mechanism and the related designs and then on computational studies. On the computational side, we examine what has been found and what is still missing with regard to properly understanding this interesting mechanism. We further discuss potential future points of computational interests toward aiming for eventually presenting in silico design guides. [ABSTRACT FROM AUTHOR]

Finding d-electron heavy fermion states has been an important topic as the diversity in d-electron materials can lead to many exotic Kondo effect-related phenomena or new states of matter such as correlation-driven topological Kondo insulator. Yet, obtaining direct spectroscopic evidence for a d-electron heavy fermion system has been elusive to date. Here, we report the observation of Kondo lattice behavior in an antiferromagnetic metal, FeTe, via angle-resolved photoemission spectroscopy, scanning tunneling spectroscopy and transport property measurements. The Kondo lattice behavior is represented by the emergence of a sharp quasiparticle and Fano-type tunneling spectra at low temperatures. The transport property measurements confirm the low-temperature Fermi liquid behavior and reveal successive coherent-incoherent crossover upon increasing temperature. We interpret the Kondo lattice behavior as a result of hybridization between localized Fe 3dxy and itinerant Te 5pz orbitals. Our observations strongly suggest unusual cooperation between Kondo lattice behavior and long-range magnetic order. The Kondo hybridization typically occurs in heavy-fermion systems containing f electrons, although recently it has been reported in d-electron systems. Kim et al. report spectroscopic evidence of the Kondo hybridization in FeTe and discuss it role in the mechanism of the magnetic order. [ABSTRACT FROM AUTHOR]

Development of new organic crystals possessing large second‐order optical nonlinearity is very challenging because of strong tendency of centrosymmetric dipole–dipole molecular assembly in crystals. This tendency makes it difficult to develop various analogous crystals that allow fine tuning of optical and physical properties to enhance the device performance. A design approach of an isomorphic crystal library consisting of 11 highly efficient nonlinear optical salt crystals is reported. Analyzing the so‐called isomorphic tolerance space in previously reported mother crystals (PMnXQ chromophores, where PM denotes piperidin‐4‐ylmethanol electron donor, n corresponds to the substituted position of halogen (X) group on the quinolinium (Q) electron acceptor), various substituents are introduced into the PMnXQ crystals at different positions, considering their space‐filling characteristics and interionic interaction ability. All 11 PMnXQ crystals exhibit an isomorphic (or pseudo‐isomorphic) crystal structure, in which the cationic chromophores form a perfectly parallel assembly for maximizing the second‐order nonlinear optical susceptibility. The optical, physical, and crystal characteristics of newly designed, synthesized, and grown isomorphic PMnXQ crystals show both similarities and differences. Excellent THz wave‐generation performance is demonstrated in both kHz‐ and MHz‐repetition optical pump systems with new PMnXQ crystals. Therefore, the design approach using isomorphic tolerance space is very attractive for developing diverse isomorphic analogous organic crystals. [ABSTRACT FROM AUTHOR]

Developing a new strategy to mitigate the trade-off between the Seebeck coefficient, electrical conductivity, and thermal conductivity is of great importance for designing highly efficient thermoelectric (TE) materials. Recently, utilizing magnetism or spin degree-of-freedom has attracted interest as an effective way to overcome such a trade-off. Here, an unprecedented pathway to enhance the Seebeck coefficient is proposed in a magnetic-impurity-doped half metal by virtue of a novel "spin polarization relaxation" mechanism. Using Fe/Co-doped higher-manganese silicides (HMSs) as a platform, it is shown that alteration of the magnetic structure and accompanying modification of the spin-dependent band structure can lead to a significantly improved Seebeck coefficient. Magnetic characterization suggests that extrinsic Fe/Co ions are antiferromagnetically coupled with intrinsic Mn ions, reducing the magnetic moment of the doped HMS. Spin-polarized density functional theory calculations disclose that such antiferromagnetic coupling leads to magnetization-induced band shifts and thus the relaxed spin polarization of density-of-states at the Fermi level. Based on those calculation results, a two-spin-channel transport model is developed to explain the relationship between the relaxed spin polarization and the drastic increase of the Seebeck coefficient in the doped HMS. Our study opens up new TE research opportunities in various spin-polarized systems such as half metals which have seldom been investigated so far. [ABSTRACT FROM AUTHOR]

Herein, we prepared an o-carborane compound (9biAT) linked to a 9,9′-bianthracene moiety at each C9-position. The compound exhibited reddish emission in solid and solution states. The solvatochromism effect and theoretical calculation results for the excited (S1) state of 9biAT verified that the emission was attributed to ICT transition. In particular, the structural rigidity and the orthogonal geometry around the carborane enhanced ICT-based emission in the solution state at 298 K, resulting in a considerably high quantum efficiency (Φem = 86%) in cyclohexane. In addition, both the Φem value and radiative decay constant (kr) gradually decreased with an increase in the polarity of the organic solvent. Theoretical modelling of the charge distribution in the S1-optimised geometry revealed that charge recombination in the radiative-relaxation process upon ICT transition could be delayed under polar conditions. Consequently, a high Φem value in the solution state at room temperature can be obtained by maintaining molecular rigidity and controlling the polarity of the environment. [ABSTRACT FROM AUTHOR]

Background: The number, location, and pattern of perforators in anterolateral thigh(ALT) flap vary and predicting them preoperatively will aid in reconstructing complex head and neck defects. This article suggests guidelines for utilizing CTA imagery to predict perforators of ALT-free flaps. Methods: We retrospectively analyzed 53 Korean patients who underwent reconstruction with ALT flap in our department from March 2021 to July 2022. The location, course, origin, and pedicle lengths predicted in CTA and confirmed in the operation field were recorded and compared. Results: Among the 85 intraoperatively-found perforators, 79 were also identified in CTA. Six perforators unidentified in CTA were newly found intraoperatively. The positive predictive value of CTA for the perforator was 100%, with a sensitivity of 79/85 = 92.9%. Of the 79 perforators depicted by the CTA for the flap, CTA and intraoperative findings for the course were consistent in 52 cases, a 9.6 mm median discrepancy being noted between the actual location and CTA. Conclusions: The overall pattern or location of perforation was not significantly different between the two, although some differences were observed. It is suggested that the addition of Doppler imaging, in conjunction with CTA, can aid in perforator detection and help minimize such discrepancies. [ABSTRACT FROM AUTHOR]

The discovery and implementation of media that derive from bioinspired designs and bear optical readouts featuring large Stokes shifts are of continued interest to a wide variety of researchers and clinicians. Myco-F, a novel mycophenolic acid precursor–based probe features a cleavable tert-butyldimethylsiloxy group to allow for fluoride detection. Myco-F exhibits high selectivity and specificity towards F− (Stokes shift = 120 nm). All measurements were performed in complete aqueous media (LOD=0.38 μM). Myco-F enables detection of fluoride ions in living HEK293 cells and localizes in the eye region (among other regions) of the zebrafish. DFT calculations support the proposed ESIPT working photomechanism. [ABSTRACT FROM AUTHOR]

Methyl orange (MO) and its protonated derivatives were investigated at the density functional theory (DFT) level using CAM‐B3LYP functional and 6‐311 + G(d,p) basis sets; their absorption spectra in aqueous solution were simulated, their relative stabilities in both the gas phase and the polar solutions were calculated, and the activation energy barrier for the cis‐to‐trans isomerization in both phases were computed. Except the protonation at the amino group, all the protonated isomers show a bathochromic shift of the most intense absorption peak. In the gas phase, the sulfonate unit turns out to be the most favorable proton acceptor. In the polar solutions, however, azo groups are more effective to accept the proton. The protonation at the azo N atom next to the phenyl‐sulfonate group significantly reduces the energy barrier for the cis‐to‐trans conversion in the aqueous solution, which suggests a swift conversion in the ground state. [ABSTRACT FROM AUTHOR]

Perchlorate has been observed in many environments on Earth and Mars but its sources remain poorly quantified. In this study, we use a global three‐dimensional chemical transport model to simulate perchlorate's gas‐phase photochemical production, atmospheric transport, and deposition on Earth's surface. Model predictions are compared to newly compiled observations of atmospheric concentrations, deposition flux, and oxygen isotopic composition of perchlorate. We find that the modeled gas‐phase production of perchlorate is consistent with reported stratospheric observations. Nevertheless, we show that this mechanism alone cannot explain the high levels of perchlorate observed at many near‐surface sites (aerosol concentrations >0.1 ng m−3 and deposition fluxes >10 g km−2 yr−1) or the low 17O‐excess observed in perchlorate sampled from pristine environments (<+18.4‰). We discuss four hypotheses to explain the model‐observation discrepancies and recommend laboratory and field observations to address key uncertainties in atmospheric sources of perchlorate. Plain Language Summary: Perchlorate (ClO4−) pollution is an environmental issue because excessive exposure can affect the thyroid and disrupt hormonal balance, especially for infants. Perchlorate on Earth has both human and natural sources. Industrial perchlorate is used for explosives and rocket fuels. Perchlorate also occurs naturally and accumulates in many deserts on Earth and in the soil of Mars. Atmospheric chemistry has long been considered a source of natural perchlorate, but its contribution remains uncertain. In this study, we use a 3‐D atmospheric model to estimate how much of the perchlorate occurrence on Earth can be explained by known and plausible reactions between gases containing chlorine and oxygen. We find that these reactions can explain the abundance of stratospheric perchlorate. However, they cannot explain many tropospheric observations of perchlorate, especially those in Antarctica and urban areas. Our analysis of oxygen isotopic anomalies also suggests that stratospheric chemistry alone cannot account for all the natural perchlorate found in deserts. We discuss four possible explanations for the differences between observations and model predictions. We recommend some future research that can reduce the uncertainties in the sources of atmospheric perchlorate and improve our understanding of the occurrence of natural perchlorate in planetary atmospheres. Key Points: We conduct the first global simulation of atmospheric perchlorate using a three‐dimensional chemical transport modelGas‐phase production of perchlorate in the stratosphere and its subsequent transport cannot explain observations at many surface sitesAnalysis of modeled and observed 17O excess suggests that non‐stratospheric sources are important for the occurrence of natural perchlorate [ABSTRACT FROM AUTHOR]

Noise reduction and control research are actively conducted as increasing noise problems compel the stringent noise requirement. Active noise control (ANC) is constructively used in various applications to reduce low-frequency noise. In previous studies, ANC systems were designed based on experiments, requiring extensive effort for effective implementation. In this paper, a real-time ANC simulation in a computational aeroacoustics framework based on the virtual-controller method is presented. The aims are to investigate sound field changes following ANC system operation and gain more insight into ANC system design through a computational approach. Using a virtual-controller ANC simulation, the approximate shape of the acoustic path filter and changes in the sound field when ANC is either "on" or "off" at the target domain can be obtained, enabling practical and detailed analyses. Then, the computational results of the duct and open space cases are predicted and compared with the experimental results to validate the prediction capability of the proposed method. In addition, the ANC system design parameters and their effects on sound fields with unintended phenomena can be predicted. Through case studies, the ability to design, optimize, and predict the performance of the ANC system using the computational method is also demonstrated. [ABSTRACT FROM AUTHOR]

The experimental realization of p-orbital systems is desirable because p-orbital lattices have been proposed theoretically to host strongly correlated electrons that exhibit exotic quantum phases. Here, we synthesize a two-dimensional Fe-coordinated bimolecular metal-organic framework which constitutes a honeycomb lattice of 1,4,5,8,9,12-hexaazatriphenylene molecules and a Kagome lattice of 5,15-di(4-pyridyl)-10,20-diphenylporphyrin molecules on a Au(111) substrate. Density-functional theory calculations show that the framework features multiple well-separated spin-polarized Kagome bands, namely Dirac cone bands and Chern flat bands, near the Fermi level. Using tight-binding modelling, we reveal that these bands are originated from two effects: the low-lying molecular orbitals that exhibit p-orbital characteristics and the honeycomb-Kagome lattice. This study demonstrates that p-orbital Kagome bands can be realized in metal-organic frameworks by using molecules with molecular orbitals of p-orbital like symmetry. The experimental realization of p-orbital systems with exotic quantum phases is desirable for the obtainment of strongly correlated materials. Here, two sublattices composed of molecules with p-orbital characteristics are combined to realize a p-orbital honeycomb-Kagome lattice in a two dimensional metal–organic framework on a Au(111) substrate. [ABSTRACT FROM AUTHOR]

Simple Summary: Evaluating disease patterns of military working dogs is important for effective preventive care. The disease patterns may be affected by breed and living and working conditions. This study reviewed medical data from the Armed Forces Medical Research Institute in the Republic of Korea. Gastrointestinal diseases due to foreign body ingestion were the most common. To prevent ingestive behavior disorders, such as foreign body ingestion, it is important to evaluate and improve the environment of military working dogs that may induce stress. Surgery for dental disease or the removal of a gastric foreign body was generally performed. Therefore, preventive care for dental disease and foreign body ingestion may be helpful for the effective performance and good quality of life in Korean military working dogs. The purpose of this study was to evaluate disease patterns among military working dogs (MWDs) at the Armed Forces Medical Research Institute (AFMRI) to provide basic medical data on Korean MWDs. The medical records of procedures performed at AFMRI between November 2017 and March 2021 were reviewed. Physical examination, diagnostic imaging, and laboratory tests were performed according to the status of each dog. A total of 353 MWDs (215 males and 138 females; mean age, 6 ± 3 years) were analyzed in this study. Among Korean MWDs, gastrointestinal (GI) disorders are the most frequently diagnosed, followed by dental and musculoskeletal disorders. Foreign body (FB) ingestion had the highest prevalence of GI disorders, with the most common FB being a leather collar or leash. General and dental surgeries, including removal of gastric FB and tooth extraction, were routinely performed at the AFMRI. Preventative care focusing on dental disease and FB ingestion may be helpful for effective performance and good quality of life in MWDs, with the regular assessment and prevention of environmental factors that may contribute to behavioral problems such as FB ingestion, coprophagy, and anorexia. [ABSTRACT FROM AUTHOR]

Background: Predominant traditional approaches for most patients who have advanced-stage oral cancer with transcervical incision lines left irreversible scars. To address this, surgeons have continuously refined minimally invasive surgery (MIS) techniques, including robot-assisted neck surgeries. This article introduces and discusses the feasibility, versatility, and availability of free-flap reconstruction via the retroauricular approach (RA), considered difficult to date. Methods: This study retrospectively analyzed 90 consecutive patients who had free-flap reconstruction performed by a single surgeon (D.K.) in the Department of Oral and Maxillofacial Surgery, Yonsei University, from March 2021 to April 2022. The type of defects and flaps, hospitalization days, total operation time, and type of vessels and anastomoses were compared statistically. Results: The type of vessels used did not differ between the RA and the transcervical approach (TA) groups, nor in duration of hospital stays. Likewise, the total reconstruction time did not differ significantly between the TA group (240 min) and the RA group (245 min) (p = 0.756). However, the total operation time was about 1 h less in the TA group, a statistically significant difference (TA group [593 ± 152 min] vs. RA group [655 ± 117 min]; p = 0.044). All flaps were successful in the RA group, whereas one flap in the TA group led to a total loss (TA group [98.3%] vs. RA group [100.0%]; p = 1.000). Conclusions: Even for patients with advanced oral cancer who require massive tumor ablation, it is feasible to obtain an aesthetic and functional surgical outcome by performing free-flap reconstruction via the retroauricular approach. [ABSTRACT FROM AUTHOR]

Vehicle vibrations cause the physical and mental fatigue, thereby degrading the riding comfort. The vehicle accelerator pedal constantly generates vibrations while driving and is in direct contact with the driver. However, relevant studies on the vibration effects of the accelerator pedal have not been sufficiently conducted. This paper presents a method to evaluate the level of vibrotactile sensation perceived by drivers due to the vehicle accelerator pedal vibration and be able to predict riding comfort. Equivalent comfort contours for foot-transmitted vibrations are derived based on the sensitivity of the foot sole measured through vibrotactile sensation tests. With the equivalent comfort contours, weighting filters for three types of vehicles—conventional gasoline, hybrid, and electric—are generated. Then, weighted vibrations representing the vibrotactile sensation level perceived by drivers from the vehicle accelerator pedal are produced by applying the weighting filters to measured vibration data from the accelerator pedal of each vehicle type. [ABSTRACT FROM AUTHOR]

Organic phototransistors exhibit great promise for use in a wide range of technological applications due to their flexibility, low cost, and low-temperature processability. However, their low transparency due to visible light absorption has hindered their adoption in next-generation transparent electronics. For this reason, the present study sought to develop a highly sensitive organic phototransistor with greater transparency and significantly higher light sensitivity in the visible and UVA regions without deterioration in its electrical properties. An organic blended thin-film transistor (TFT) fabricated from the blend of an organic semiconductor and an insulating polymer demonstrated improved electrical properties in the dark and a higher current under light irradiation even though its transmittance was higher. The device exhibited a transmittance of 87.28% and a photosensitivity of 7049.96 in the visible light region that were 4.37% and 980 times higher than those of the single-semiconductor-based device. The carrier mobility of the device blended with the insulating polymer was improved and greatly amplified under light irradiation. It is believed that the insulating polymer facilitated the crystallization of the organic semiconductor, thus promoting the flow of photogenerated excitons and improving the photocurrent. Overall, the proposed TFT offers excellent low-temperature processability and has the potential to be employed in a range of transparent electronic applications. [ABSTRACT FROM AUTHOR]

To realize oxide semiconductor-based complementary circuits and better transparent display applications, the electrical properties of p-type oxide semiconductors and the performance improvement of p-type oxide thin-film transistors (TFTs) are required. In this study, we report the effects of post-UV/ozone (O3) treatment on the structural and electrical characteristics of copper oxide (CuO) semiconductor films and the TFT performance. The CuO semiconductor films were fabricated using copper (II) acetate hydrate as a precursor material to solution processing and the UV/O3 treatment was performed as a post-treatment after the CuO film was fabricated. During the post-UV/O3 treatment for up to 13 min, the solution-processed CuO films exhibited no meaningful change in the surface morphology. On the other hand, analysis of the Raman and X-ray photoemission spectra of solution-processed CuO films revealed that the post-UV/O3 treatment induced compressive stress in the film and increased the composition concentration of Cu–O lattice bonding. In the post-UV/O3-treated CuO semiconductor layer, the Hall mobility increased significantly to approximately 280 cm2 V−1 s−1, and the conductivity increased to approximately 4.57 × 10−2 Ω−1 cm−1. Post-UV/O3-treated CuO TFTs also showed improved electrical properties compared to those of untreated CuO TFTs. The field-effect mobility of the post-UV/O3-treated CuO TFT increased to approximately 6.61 × 10−3 cm−2 V−1 s−1, and the on-off current ratio increased to approximately 3.51 × 103. These improvements in the electrical characteristics of CuO films and CuO TFTs can be understood through the suppression of weak bonding and structural defects between Cu and O bonds after post-UV/O3 treatment. The result demonstrates that the post-UV/O3 treatment can be a viable method to improve the performance of p-type oxide TFTs. [ABSTRACT FROM AUTHOR]

Although in terahertz (THz) source materials molecular anions significantly influence the performance of THz generation, only limited classes of molecular counter anions have been reported. Here, utilizing dichlorinated molecular anions in THz generators is reported for the first time, to the best of our knowledge. In these new crystals, two dichlorinated molecular anions with different molecular symmetries, asymmetric 3,4‐dichlorobenzenesulfonate (34DCS) and symmetric 3,5‐dichlorobenzenesulfonate (35DCS), are incorporated with a 2‐(4‐hydroxystyryl)‐1‐methylquinolinium (OHQ) cation possessing top‐level molecular optical nonlinearity. OHQ‐34DCS exhibits a strong nonlinear optical response, in contrast to OHQ‐35DCS. In OHQ‐34DCS crystals, the dichlorinated groups form strong halogen bonds (XBs) and hydrogen bonds (HBs), which are beneficial for suppressing molecular (phonon) vibrations. The optical‐to‐THz conversion efficiency of the OHQ‐34DCS crystals is extremely high, comparable to that of the benchmark organic THz generators. Moreover, the THz emission spectra from the OHQ‐34DCS crystals, compared to those of previously reported benchmark analogous crystals, are stronger modulated toward a flatter shape, but possess substantially reduced spectral dimples. Therefore, the introduction of dichlorinated molecular anions is an efficient approach for the design of highly efficient electro‐optic salt crystals as efficient broadband THz wave sources. [ABSTRACT FROM AUTHOR]