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Multi-level inverters have characteristics suitable for high-voltage and high-power applications through various topology configurations. These reduce harmonic distortion and improve the quality of the output waveform by generating a multi-level output voltage waveform. In particular, an active neutral-point-clamped topology is one of the multi-level inverters advantageous for high-power and medium-voltage applications. It has the advantage of controlling the output waveform more precisely by actively clamping the neutral point using an active switch and diode. However, it has a problem, which is that an unwanted zero-crossing current may occur if an inaccurate switching signal is applied at the time when the polarity of the output voltage changes. In this paper, a control strategy to suppress the zero-crossing current of a single-phase half-bridge three-level active neutral-point-clamped inverter is proposed. The operating principle of a single-phase half-bridge three-level active neutral-point-clamped inverter is identified through an operation mode analysis. In addition, how the switching signal is reflected in an actual digital signal processor is analyzed to determine the situation in which the zero-crossing current occurs. Through this, a control strategy capable of suppressing zero-crossing current is designed. The proposed method prevents a zero-crossing current by appropriately modifying the update timing of reference voltages at the point where the polarity of the output changes. The validity of the proposed method is verified through simulation and experiments. Based on the proposed method, the total harmonic distortion of the output current is significantly reduced from 12.15% to 4.59% in a full-load situation. [ABSTRACT FROM AUTHOR]

Background/Objectives: Target tetra detachable coils (TTDCs) aid in achieving effective framing during the coil embolization of small intracranial aneurysms by maintaining a tetrahedral conformation within the aneurysm sac. We aimed to report the initial experience of patients treated for intracranial aneurysms using TTDCs, with a specific focus on efficacy and safety. Methods: We retrospectively reviewed the medical records of 41 patients who underwent the coil embolization of intracranial aneurysms sized ≤10 mm with TTDCs between April and May 2023. Post-procedural angiographic and clinical results were reviewed. Results: Of the 46 aneurysms (45 unruptured and 1 ruptured), 33 (71.7%) were treated with the stent-assisted technique and 13 (28.3%) using the simple coil embolization technique. Post-procedural angiography showed complete occlusion in 41 aneurysms (89.1%), neck remnants in 1 (2.2%), and residual aneurysms in 4 (8.7%). The mean packing density was 34.7% (19.3–46.8%), with TTDC coil length comprising a mean of 88.5% of the total coil length. No major device- or procedure-related complications were observed. During the follow-up, 40 aneurysms (93.0%) demonstrated complete occlusion, while neck remnants were observed in 1 (2.3%), and residual aneurysms in 2 (4.7%). No cases of recanalization were observed. Conclusions: The TTDC is a safe and effective device for the endovascular treatment of intracranial aneurysms. Follow-up studies are required to establish long-term results. [ABSTRACT FROM AUTHOR]

Background: Flow diversion has significantly improved the management of cerebral aneurysms. Technological advancements and increased clinical experience over the past decade have led to better outcomes and fewer complications. This study provides updated results and examines the factors that influence the success of flow diversion. Methods: We reviewed records of 115 patients with 121 intracranial aneurysms treated from July 2014 to August 2023. All patients had unruptured aneurysms in the anterior and posterior circulation. Results: Complete aneurysm occlusion was achieved in 72.7% of cases, with a complication rate of 9.1%. Significant predictors of complete occlusion included aneurysm diameter (OR = 0.89, 95% CI 0.82–0.97, p = 0.009) and the presence of incorporated branches (OR = 0.22, 95% CI 0.08–0.59, p = 0.003). Cox analysis identified neck diameter (HR = 0.92, 95% CI 0.87–0.98, p = 0.009) and incorporated branch (HR = 0.40, 95% CI 0.24–0.69, p = 0.001) as significant for occlusion. Multivariable analysis identified aneurysm diameter (OR = 1.21, 95% CI 1.09–1.37, p = 0.001) as significant for safety outcomes. Improved outcomes were observed in recent treatments, with higher occlusion rates (79.7% vs. 61.7%, p = 0.050) and lower complication rates (4.1% vs. 14.9%, p = 0.011). Conclusions: Enhanced technical proficiency, better devices, and refined patient selection have significantly improved the efficacy and safety of flow diversion for cerebral aneurysms. Identifying significant predictors for treatment success and safety outcomes can inform clinical practice, aiding in patient selection. [ABSTRACT FROM AUTHOR]

Premature loss of root canal-treated primary teeth has long been a concern in dentistry. To address this, researchers developed a sodium iodide-based root canal-filling material as an alternative to traditional iodoform-based materials. The goal of this study was to improve the physicochemical properties of the sodium iodide-based material to meet clinical use standards. To resolve high solubility issues in the initial formulation, researchers adjusted component ratios and added new ingredients, resulting in a new paste called L5. This study compared L5 with L0 (identical composition minus lanolin) and Vitapex as controls, conducting physicochemical and antibacterial tests. Results showed that L5 met all ISO 6876 standards, demonstrated easier injection and irrigation properties than Vitapex, and exhibited comparable antibacterial efficacy to Vitapex, which is currently used clinically. The researchers conclude that if biological stability is further verified, L5 could potentially be presented as a new option for root canal-filling materials in primary teeth. [ABSTRACT FROM AUTHOR]

Overall linear instability characteristics of an asymptotically thin reactive layer in a flame are investigated, particularly for Liñán's premixed-flame regime of activation-energy asymptotics. The reactive-layer instability analysis, formulated with the characteristic length and timescales of the inner reaction zone, is carried out not only by a numerical method but also by an asymptotic method, with the small expansion parameter $m$ m obeying the distinguished limit of ${\beta ^{ - 1}} \ll |m| \ll 1$ β − 1 ≪ | m | ≪ 1 and $L - 1 = {\rm{O}}(m)$ L − 1 = O (m) , where $m$ m , $\beta $ β , and $L$ L denote the downstream heat-loss factor, the Zel'dovich number, and the Lewis number, respectively. The asymptotic analysis yields an explicit dispersion relation, which is comprised of three distinct destabilizing or stabilizing contributions: (i) the reaction sensitivity associated with the downstream heat-loss effect, (ii) the reaction sensitivity associated with the preferential diffusion effect, and (iii) the diffusive relaxation. Three instability modes, namely cellular instability, planar instability, and pulsating instability, are found to be similar to the conventional diffusional-thermal instability. Consequently, the reactive-layer instability is seen to be good enough to serve as a general baseline for diffusional-thermal instability, despite lacking the detailed instability characterization in the ${\rm{O}}({\beta ^{ - 1}})$ O (β − 1 ) proximity of $L = 1$ L = 1 , the corrections for which can be achieved by the conventional diffusional-thermal instability analysis within the NEF (nearly-equidiffusional flame) limit. [ABSTRACT FROM AUTHOR]

Extinction of strained chain-branching premixed flames with nonunity fuel and chain-carrier Lewis numbers is asymptotically analyzed by employing an NEF (Nearly Equidiffusional Flame) limit modified specifically for the Zel'dovich-Liñán two-step mechanism. The asymptotic chain-branching flame-structure analysis is carried out within the framework of the intermediate recombination regime, in which the recombination layer is asymptotically thicker than the inner chain-branching layer, but thinner than the outer convective-diffusive layer. In order to construct a consistent activation-energy asymptotics for the thinnest chain branching layer, thickness of the intermediate recombination-layer as well as deviation of the chain-carrier Lewis number from unity is scaled by the inverse square root of the chain-branching Zel'dovich number. Because the fuel is consumed only by the chain-branching reaction, characterized by a large chain-branching Zel'dovich number, the influences of nonunity fuel Lewis number on extinction with two-step chemistry is found to be qualitatively almost identical to that with overall one-step chemistry. Therefore, strained chain-branching flames can be extinguished by increasing the flow strain rate if the fuel Lewis number is sufficiently large. However, the chain-carrier Lewis number is found to be not capable of qualitatively influencing the extinction characteristics because the peak chain-carrier concentration tends to remain almost invariant with varying flow strain rate. Abrupt extinction is more readily observed for the faster recombination regime, for which the overall effective nonlinearity of the two-step mechanism becomes larger. Finally, the critical Lewis number boundary for extinction is predominantly dependent on the fuel Lewis number. Consequently, the overall extinction characteristics of strained chain-branching flames is found to be qualitatively similar to that found within the framework of the overall single-step activation-energy asymptotics. [ABSTRACT FROM AUTHOR]

A series of far-detector programs have been proposed for operation at various interaction points of the large hadron collider during the upcoming runs. Investigating the potential and complementarity of these experiments for new-physics searches goes through the estimation of their sensitivity to specific long-lived particle models. Here, we present an integrated numerical tool written in the C++ language and called Displaced Decay Counter, which we have created to this end and which can be used in association with MadGraph5, Pythia8, or any other state-of-the-art Monte-Carlo collider simulation tool. Several far-detector models have been implemented within the program, accounting for the geometry and integrated luminosity of projected detectors. Additional or more accurate designs can be easily constructed through a dedicated interface. The functionality of this tool is exemplified through the discussion of several benchmark scenarios, which we consider for the validation of the implemented detector models. [ABSTRACT FROM AUTHOR]

This paper presents a circuit for detecting and protecting against short circuits in E-mode gallium nitride high-electron-mobility transistors (GaN HEMTs) and analyzes the protection performance of the circuit. GaN HEMTs possess fast switching characteristics that enable high efficiency and power density in power conversion devices. However, these characteristics also pose challenges in protecting against short circuits and overcurrent situations. The proposed method detects short-circuit events by monitoring an instantaneous drop in the DC bus voltage of a circuit with GaN HEMTs applied and uses a bandpass filter to prevent the malfunction of the short-circuit protection circuit during normal switching and ensure highly reliable operation. Using this method, the short-circuit detection time of E-mode GaN HEMTs can be reduced to 257 ns, successfully protecting the device without malfunctions even in severe short-circuit situations occurring at high DC link voltages. [ABSTRACT FROM AUTHOR]

The asymptotic structure of stretched chain-branching premixed flames with unity Lewis numbers is analyzed with the Zel'dovich-Liñán two-step mechanism, including (I) temperature-sensitive autocatalytic chain-branching step and (II) first-order chain-recombination step with combustion heat release. Depending on the order-of-magnitude of the Damköhler number ratio between the branching and recombination reactions, three distinct asymptotic limits, namely the fast, intermediate and slow recombination regimes, emerge with their own distinct multi-layer asymptotic structures. Our attention is focused on the asymptotic chain-branching flame-structure analysis within the framework of the intermediate recombination regime, in which the recombination layer is asymptotically thicker than the branching layer, but thinner than the outer convective-diffusive layer. The multi-layer asymptotics, involving the Damköhler number asymptotics for the recombination layer and the activation-energy asymptotics for the branching layer, yields the chain-branching flame-structure solution. The calculation results reveal the unique characteristics of strained chain-branching flames. First, the chain-carrier concentration and temperature at the branching reaction sheet are found to be constant irrespective of the strain rate. The chain-carrier concentration increases as the recombination reaction becomes slower. Moreover, the chain-carrier concentration at the branching reaction sheet is found to be proportional to the laminar flame speed. However, no quasisteady extinction was observed in any calculation results because the branching-reaction rate manages to maintain its strength thanks to the invariant branching-layer temperature. It is worthwhile to note that the present two-step model for chain-branching flames is perhaps the simplest asymptotic model, involving the minimum number of kinetic parameters to properly describe the asymptotic structure without losing any physical essence. [ABSTRACT FROM AUTHOR]

Calcium silicate-based cement (CSC) is a pharmaceutical agent that is widely used in dentistry. This bioactive material is used for vital pulp treatment due to its excellent biocompatibility, sealing ability, and antibacterial activity. Its drawbacks include a long setting time and poor maneuverability. Hence, the clinical properties of CSC have recently been improved to decrease its setting time. Despite the widespread clinical usage of CSC, there is no research comparing recently developed CSCs. Therefore, the purpose of this study is to compare the physicochemical, biological, and antibacterial properties of four commercial CSCs: two powder–liquid mix types (RetroMTA® [RETM]; Endocem® MTA Zr [ECZR]) and two premixed types (Well-Root™ PT [WRPT]; Endocem® MTA premixed [ECPR]). Each sample was prepared using circular Teflon molds, and tests were conducted after 24 h of setting. The premixed CSCs exhibited a more uniform and less rough surface, higher flowability, and lower film thickness than the powder–liquid mix CSCs. In the pH test, all CSCs showed values between 11.5 and 12.5. In the biological test, cells exposed to ECZR at a concentration of 25% showed greater cell viability, but none of the samples showed a significant difference at low concentration (p > 0.05). Alkaline phosphatase staining revealed that cells exposed to ECZR underwent more odontoblast differentiation than the cells exposed to the other materials; however, no significant difference was observed at a concentration of 12.5% (p > 0.05). In the antibacterial test, the premixed CSCs showed better results than the powder–liquid mix CSCs, and ECPR yielded the best results, followed by WRPT. In conclusion, the premixed CSCs showed improved physical properties, and of the premixed types, ECPR exhibited the highest antibacterial properties. For biological properties, none of these materials showed significant differences at 12.5% dilution. Therefore, ECPR may be a promising material with high antibacterial activity among the four CSCs, but further investigation is needed for clinical situations. [ABSTRACT FROM AUTHOR]

Schisandra chinensis (Turcz.) Baill. has been traditionally used as a medicine for bronchial tube ailments in Northeast Asia. Recently, the demand for S. chinensis has increased for use as food and medicine because of the lignans found in its fruits. However, the species germplasm collection has rarely been studied to evaluate their phenotypic traits in Korea. In this study, 96 accessions of S. chinensis were collected in South Korea for two years to evaluate their phenotypes, and principal component analysis (PCA) and cluster analysis were conducted. Significant variations among the measured phenotypic traits were observed. The total bunch weight produced from a single tree ranged from 109 to 5844 g; the contents in schizandrin, gomisin A, and gomisin N—three types of lignan—were 2.2–14.5, 0.9–9.8, and 2.1–12.2 mg/g, respectively. Gomisin N positively correlated with flowering traits (flowering start, period, and peduncle length) and leaf characteristics (leaf width and length). PCA and cluster analyses revealed four clusters among the 96 S. chinensis accessions. These results provide valuable information for systematic characterization of species germplasm collections and tools for further research. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of different viscosities of silicone oil on the physicochemical, pre-clinical usability, and biological properties of a sodium iodide paste. Six different paste groups were created by mixing therapeutic molecules, sodium iodide (D30) and iodoform (I30), with calcium hydroxide and one of the three different viscosities of silicone oil (high (H), medium (M), and low (L)). The study evaluated the performance of these groups, including I30H, I30M, I30L, D30H, D30M, and D30L, using multiple parameters such as flow, film thickness, pH, viscosity, and injectability, with statistical analysis (p < 0.05). Remarkably, the D30L group demonstrated superior outcomes compared to the conventional iodoform counterpart, including a significant reduction in osteoclast formation, as examined through TRAP, c-FOS, NFATc1, and Cathepsin K (p < 0.05). Additionally, mRNA sequencing showed that the I30L group exhibited increased expression of inflammatory genes with upregulated cytokines compared to the D30L group. These findings suggest that the optimized viscosity of the sodium iodide paste (D30L) may lead to clinically favorable outcomes, such as slower root resorption, when used in primary teeth. Overall, the results of this study suggest that the D30L group shows the most satisfactory outcomes, which may be a promising root-filling material that could replace conventional iodoform-based pastes. [ABSTRACT FROM AUTHOR]

Surface-wave plasma which generates a specific wave mode between the plasma and a dielectric window by microwave is superior to RF plasmas in producing relatively higher electron density at low temperature. To challenge the uniformity issue of the microwave plasma whose wavelength is shorter than the size of the industrial system, rotating field systems by imparting a phase difference of microwaves from multiple inputs over time are attracting attention. The authors investigate the feasibility of a phase-locked-loop (PLL) injected magnetron (MGT) as a highly efficient microwave source to modulate the phase difference of high-power microwaves fast and precisely. The phase-transition time of the MGT with a plasma load is estimated to be below 45 ns by theoretical analysis and experimental measurement. The results show that the phase-modulation frequency of microwaves with the PLL-injected MGT is capable of reaching up to 10 MHz. [ABSTRACT FROM AUTHOR]

We present updated LHC limits on the minimal universal extra dimensions (MUEDs) model from the Run 2 searches. We scan the parameter space against a number of searches implemented in the public code CheckMATE and derive up-to-date limits on the MUED parameter space from 13 TeV searches. The strongest constraints come from a search dedicated to squarks and gluinos with one isolated lepton, jets and missing transverse energy. In the procedure, we take into account initial state radiation and stress its importance in the MUED searches, which is not always appreciated. [ABSTRACT FROM AUTHOR]

Intramolecular charge transfer (ICT) plays a critical role in determining the photophysical properties of organic molecules, including their luminescence efficiencies. Twisted intramolecular charge transfer (TICT) is a process in which structural change accompanies ICT. Herein, we used time-resolved spectroscopy to study TICT in pyrene derivatives that are promising blue organic light emitting diode (OLED) emitter candidates; these derivatives show strong solvent-dependent charge-transfer (CT) behavior with unique fluorescence properties, increased fluorescence intensity in polar solvent. Slight structural changes that do not affect excited state dynamics were observed in nonpolar solvents, while polar solvents were found to affect excited state dynamics and CT characteristics, which affect their unusual fluorescence behavior. The TICT behavior of these pyrene derivatives can be modulated through structural modification. Our study provides valuable guidelines for the control of optical properties, including the luminescence efficiencies of OLED emitters that show TICT characteristics. [ABSTRACT FROM AUTHOR]

Silver diamine fluoride (SDF) is an outstanding dental material for arresting and preventing caries, but some drawbacks, such as high flowability due to low viscosity and cytotoxicity to the pulp, have been reported. To overcome these problems, copper-doped bioactive glass nanoparticles (CuBGns) were combined with SDF. After synthesis, CuBGns were examined by physical analysis and added in SDF at different weight/volume% (SDF@CuBGn). After assessing physical properties (viscosity and flowability) of SDF@CuBGn, physicochemical properties (morphology before and after simulated body fluid (SBF) immersion and ion release) of SDF@CuBGn-applied hydroxyapatite (HA) discs were evaluated. Biological properties were further evaluated by cytotoxicity test to pulp stem cells and antibacterial effect on cariogenic organisms (Streptococcus mutans and Staphylococcus aureus). Combining CuBGns in SDF increased the viscosity up to 3 times while lowering the flowability. More CuBGns and functional elements in SDF (Ag and F) were deposited on the HA substrate, even after SBF immersion test for 14 days, and they showed higher Cu, Ca, and Si release without changing F and Ag release. Cell viability test suggested lower cytotoxicity in SDF@CuBGn-applied HA, while CuBGns in SDF boosted antibacterial effect against S. aureus, ~27% in diameter of agar diffusion test. In conclusion, the addition of CuBGn to SDF enhances viscosity, Ag and F deposition, and antibacterial effects while reducing cell toxicity, highlighting the role of bioactive CuBGns for regulating physical and biological effects of dental materials. [ABSTRACT FROM AUTHOR]

Therapeutic iodoform (CHI3) is commonly used as a root-filling material for primary teeth; however, the side effects of iodoform-containing materials, including early root resorption, have been reported. To overcome this problem, a water-soluble iodide (NaI)-incorporated root-filling material was developed. Calcium hydroxide, silicone oil, and NaI were incorporated in different weight proportions (30:30:X), and the resulting material was denoted DX (D5~D30), indicating the NaI content. As a control, iodoform instead of NaI was incorporated at a ratio of 30:30:30, and the material was denoted I30. The physicochemical (flow, film thickness, radiopacity, viscosity, water absorption, solubility, and ion releases) and biological (cytotoxicity, TRAP, ARS, and analysis of osteoclastic markers) properties were determined. The amount of iodine, sodium, and calcium ion releases and the pH were higher in D30 than I30, and the highest level of unknown extracted molecules was detected in I30. In the cell viability test, all groups except 100% D30 showed no cytotoxicity. In the 50% nontoxic extract, D30 showed decreased osteoclast formation compared with I30. In summary, NaI-incorporated materials showed adequate physicochemical properties and low osteoclast formation compared to their iodoform-counterpart. Thus, NaI-incorporated materials may be used as a substitute for iodoform-counterparts in root-filling materials after further (pre)clinical investigation. [ABSTRACT FROM AUTHOR]

Pulp regeneration has recently attracted interest in modern dentistry. However, the success ratio of pulp regeneration is low due to the compromising potential of stem cells, such as their survival, migration, and odontoblastic differentiation. Stem cells from human exfoliated deciduous teeth (SHED) have been considered a promising tool for regenerative therapy due to their ability to secrete multiple factors that are essential for tissue regeneration, which is achieved by minimally invasive procedures with fewer ethical or legal concerns than those of other procedures. The aim of this study is to investigate the potency of SHED-derived conditioned media (SHED CM) on dental pulp stem cells (DPSCs), a major type of mesenchymal stem cells for dental pulp regeneration. Our results show the promotive efficiency of SHED CM on the proliferation, survival rate, and migration of DPSCs in a dose-dependent manner. Upregulation of odontoblast/osteogenic-related marker genes, such as ALP, DSPP, DMP1, OCN, and RUNX2, and enhanced mineral deposition of impaired DPSCs are also observed in the presence of SHED CM. The analysis of SHED CM found that a variety of cytokines and growth factors have positive effects on cell proliferation, migration, anti-apoptosis, and odontoblast/osteogenic differentiation. These findings suggest that SHED CM could provide some benefits to DPSCs in pulp regeneration. [ABSTRACT FROM AUTHOR]

Purpose: Here, we presented our early experience with flow diversion procedures using the Surpass Evolve flow diverter (SE, Stryker) and reported the feasibility and safety profile compared to those of a control group treated with other types of flow diverters. Methods: We included 31 and 53 consecutive flow diversion procedures performed using the SE and other commercial flow diverters, respectively, to treat intracranial aneurysms at our institution. We used two commercial flow diversion systems in the comparison group: the pipeline embolization device and Surpass Streamline. Results: In the SE group, technical failures occurred in three (9.7%) cases, due to either incomplete wall apposition (n = 1, 3.2%) or stent migration (n = 2, 6.5%). Major complications occurred in four (12.9%) cases: delayed rupture of the target aneurysm (n = 1, 3.2%), major ischemic stroke (n = 1, 3.2%), sudden death from an unidentified cause (n = 1, 3.2%), and parent artery occlusion with stent thrombosis (n = 1, 3.2%). Balloon angioplasty was performed in eight (25.8%) cases. On post-procedure MRI, a DWI-positive lesion was detected in three (9.7%) cases. After multivariate adjustment, the SE group was independently associated with less procedural time of ≥ 90 min (adjusted OR, 0.09; 95% CI, 0.03–0.29; p < 0.001), balloon angioplasty (adjusted OR, 0.22; 95% CI, 0.07–0.75; p = 0.015), and DWI-positive lesions (adjusted OR, 0.04; 95% CI, 0.01–0.19; p < 0.001). Conclusion: The SE is safe and easy to deploy. [ABSTRACT FROM AUTHOR]

To utilize thermally activated delayed fluorescence (TADF) technology for future displays, it is necessary to develop host materials which harness the full potential of blue TADF emitters. However, no publication has reported such hosts yet. Although the most popular host for blue TADF, bis[2‐(diphenylphosphino)phenyl]ether oxide (DPEPO) guarantees high‐maximum external quantum efficiency (EQEmax) TADF devices, they exhibit very short operational lifetimes. In contrast, long‐lifespan blue TADF devices employing stable hosts such as 3′,5‐di(9H‐carbazol‐9‐yl)‐[1,1′‐biphenyl]‐3‐carbonitrile (mCBP‐CN) exhibit much lower EQEmax than the DPEPO‐employed devices. Here, an elaborative approach for designing host molecules is suggested to achieve simultaneously stable and efficient blue TADF devices. The approach is based on engineering the molecular geometry, ground‐ and excited‐state dipole moments of host molecules. The engineered hosts significantly enhance delayed fluorescence quantum yields of TADF emitters, as stabilizing the charge‐transfer excited states of the TADF emitters and suppressing exciton quenching, and improve the charge balance. Moreover, they exhibit both photochemical and electrochemical stabilities. The best device employing one of the engineered hosts exhibits 79% increase in EQEmax compared to the mCBP‐CN‐employed device, together with 140% and 92‐fold increases in operational lifetime compared to the respective mCBP‐CN‐ and the DPEPO‐based devices. [ABSTRACT FROM AUTHOR]

Long-lived particles have become a new frontier in the exploration of physics beyond the Standard Model. In this paper, we present the implementation of four types of long-lived particle searches, viz. displaced leptons, disappearing track, displaced vertex with either muons or with missing transverse energy, and heavy charged tracks. These four categories cover the signatures of a large range of physics models. We illustrate their potential for exclusion and discuss their mutual overlaps in mass-lifetime space for two simple phenomenological models involving either a U(1)-charged or a coloured scalar. [ABSTRACT FROM AUTHOR]

Although the organic light‐emitting diode (OLED) has been successfully commercialized, the development of deep‐blue OLEDs with high efficiency and long lifetime remains a challenge. Here, a novel hyperfluorescent OLED that incorporates the Pt(II) complex (PtON7‐dtb) as a phosphorescent sensitizer and a hydrocarbon‐based and multiple resonance‐based fluorophore as an emitter (TBPDP and ν‐DABNA) in the device emissive layer (EML), is proposed. Such an EML system can promote efficient energy transfer from the triplet excited states of the sensitizer to the singlet excited states of the fluorophore, thus significantly improving the efficiency and lifetime of the device. As a result, a deep‐blue hyperfluorescent OLED using a multiple resonance‐based fluorophore (ν‐DABNA) with Commission Internationale de L'Eclairage chromaticity coordinate y below 0.1 is demonstrated, which attains a narrow full width at half maximum of ≈17 nm, fourfold increased maximum current efficiency of 48.9 cd A−1, and 19‐fold improved half‐lifetime of 253.8 h at 1000 cd m−2 compared to a conventional phosphorescent OLED. The findings can lead to better understanding of the hyperfluorescent OLEDs with high performance. [ABSTRACT FROM AUTHOR]

Much effort has been dedicated to increase the operational lifetime of blue phosphorescent materials in organic light‐emitting diodes (OLEDs), but the reported device lifetimes are still too short for the industrial applications. An attractive method for increasing the lifetime of a given emitter without making any chemical change is exploiting the kinetic isotope effect, where key CH bonds are deuterated. A computer model identifies that the most vulnerable molecular site in an Ir‐phenylimidazole dopant is the benzylic CH bond and predicts that deuteration may hamper the deactivation pathway involving CH/D bond cleavage notably. Experiments show that the device lifetime until the initial luminance diminishes to 70% (LT70) of a prototype phosphorescent OLED device can be doubled to 355 hours with a maximum external quantum efficiency of 25.1% at 1000 cd m−2. This is one of the best operational performances of blue phosphorescent OLEDs observed to date in a single stacked cell. [ABSTRACT FROM AUTHOR]

Much effort has been dedicated to increase the operational lifetime of blue phosphorescent materials in organic light‐emitting diodes (OLEDs), but the reported device lifetimes are still too short for the industrial applications. An attractive method for increasing the lifetime of a given emitter without making any chemical change is exploiting the kinetic isotope effect, where key CH bonds are deuterated. A computer model identifies that the most vulnerable molecular site in an Ir‐phenylimidazole dopant is the benzylic CH bond and predicts that deuteration may hamper the deactivation pathway involving CH/D bond cleavage notably. Experiments show that the device lifetime until the initial luminance diminishes to 70% (LT70) of a prototype phosphorescent OLED device can be doubled to 355 hours with a maximum external quantum efficiency of 25.1% at 1000 cd m−2. This is one of the best operational performances of blue phosphorescent OLEDs observed to date in a single stacked cell. [ABSTRACT FROM AUTHOR]

Background: The folate metabolism that converts homocysteine to methionine is closely related to the accumulation of homocysteine. Increased homocysteine levels lead to an impaired antithrombotic function of the vascular endothelium and uterine-placental circulation, resulting in abnormal pregnancy outcomes. Previous studies have reported that gene polymorphisms in folate metabolism are associated with the development of preterm birth (PTB) in various populations. Objective: we performed a case–control study to evaluate the association between five polymorphisms in folate metabolic genes (MTHFR, MTR, MTRR, TCN2) and PTB. Methods: In this study, a total of 254 subjects were analyzed (111 patients with PTB and 143 women at ≥ 38 weeks of gestation). Genotype and allele frequency differences between patients and control groups and the Hardy–Weinberg equilibrium were assessed using a Chi-square test. For evaluation indicators, odds ratios (ORs) of 95% confidence intervals (CI) were estimated. In addition, we analyzed the combined genotype frequencies of SNPs of folate-metabolizing genes to measure gene–gene interactions for PTB. Results: Our results showed that the MTR rs1805087 GG (p = 0.031), and TCN2 rs1801198 CG genotype (OR 0.53, 95% CI 0.288–0.980, p = 0.042) were significantly associated with PTB. The MTHFR rs4846049 AA showed a marginal trend toward significance (OR 0.15, 95% CI 0.018–1.205, p = 0.041). In particular, the combined genotypes, including MTHFR rs1537514 CC—MTRR rs1801394 GG, MTHFR rs1537514 CC—TCN2 rs1801198 CG, and MTR rs1805087 AA—TCN2 rs1801198 CG, have significant interactions with PTB (OR 0.49, 95% CI 0.248–0.992, p < 0.05). Conclusion: The polymorphisms of folate metabolic genes may have a genetic association with the development of PTB in Korean women. A larger sample set and functional studies are required to further elucidate our findings. [ABSTRACT FROM AUTHOR]

Although the organic light‐emitting diode (OLED) has been successfully commercialized, the development of deep‐blue OLEDs with high efficiency and long lifetime remains a challenge. Here, a novel hyperfluorescent OLED that incorporates the Pt(II) complex (PtON7‐dtb) as a phosphorescent sensitizer and a hydrocarbon‐based and multiple resonance‐based fluorophore as an emitter (TBPDP and ν‐DABNA) in the device emissive layer (EML), is proposed. Such an EML system can promote efficient energy transfer from the triplet excited states of the sensitizer to the singlet excited states of the fluorophore, thus significantly improving the efficiency and lifetime of the device. As a result, a deep‐blue hyperfluorescent OLED using a multiple resonance‐based fluorophore (ν‐DABNA) with Commission Internationale de L'Eclairage chromaticity coordinate y below 0.1 is demonstrated, which attains a narrow full width at half maximum of ≈17 nm, fourfold increased maximum current efficiency of 48.9 cd A−1, and 19‐fold improved half‐lifetime of 253.8 h at 1000 cd m−2 compared to a conventional phosphorescent OLED. The findings can lead to better understanding of the hyperfluorescent OLEDs with high performance. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the diagnostic performance achieved by using fully-connected small artificial neural networks (ANNs) and a simple training process, the Kim-Monte Carlo algorithm, to detect the location of pneumothorax in chest X-rays. A total of 1,000 chest X-ray images with pneumothorax were taken randomly from NIH (the National Institutes of Health) public image database and used as the training and test sets. Each X-ray image with pneumothorax was divided into 49 boxes for pneumothorax localization. For each of the boxes in the chest X-ray images contained in the test set, the area under the receiver operating characteristic (ROC) curve (AUC) was 0.882, and the sensitivity and specificity were 80.6% and 83.0%, respectively. In addition, a common currently used deep-learning method for image recognition, the convolution neural network (CNN), was also applied to the same dataset for comparison purposes. The performance of the fully-connected small ANN was better than that of the CNN. Regarding the diagnostic performances of the CNN with different activation functions, the CNN with a sigmoid activation function for fully-connected hidden nodes was better than the CNN with the rectified linear unit (RELU) activation function. This study showed that our approach can accurately detect the location of pneumothorax in chest X-rays, significantly reduce the time delay incurred when diagnosing urgent diseases such as pneumothorax, and increase the effectiveness of clinical practice and patient care. [ABSTRACT FROM AUTHOR]

Simultaneously achieving both a high efficiency and long lifetime in deep-blue organic light-emitting diodes is challenging. Here we report thermally activated delayed fluorescence (TADF) organic light-emitting diodes that aim to meet this goal by combining a new design of blue TADF materials with a triplet-exciton recycling protocol. Two TADF materials, one distributing and one emitting, were doped into a host to form triplet-exciton-distributed TADF devices. The singlet excitons were transferred from the host to the emitter via the distributing TADF material by cascade energy transfer, whereas the triplet excitons were transferred to the emitter as singlet excitons by a triplet-exciton recycling process between the low-triplet-energy host and the distributing TADF material. The resulting triplet-exciton-distributed TADF devices achieved a high external quantum efficiency of 33.5 ± 0.1, a colour coordinate corrected current efficiency over 400 cd A–1, a lifetime of >5,000 h and a y colour coordinate below 0.10. Exciton energy cascade transfer and recycling bring improvements in the efficiency and lifetime of deep-blue organic light-emitting diodes. [ABSTRACT FROM AUTHOR]

Novel homoleptic cyclometalated Ir(III) complexes are designed to improve their emission dipole orientations in the emitting layer of blue phosphorescent organic light emitting devices. Biphenyl group is introduced into the imidazole of cyclometalated Ir(III) complexes to simultaneously achieve enhanced efficiency and operation lifetime, resulting in one of the best device performances of single‐stacked organic light emitting diodes with 91% emission dipole orientation, 26.3% maximum external quantum efficiency (maximally calculated as 41%), and 169 h lifetime at 1000 cd m−2 (LT80), color coordinate (0.17, 0.30). To elucidate the physical origin of this significant improvements, the orientational and positional distributions of the homoleptic dopants are analyzed with consideration on intermolecular interactions through atomistic modeling of the emitting layer. With the findings, the phosphorescent dopants could be designed in the future to achieve enhanced performance. [ABSTRACT FROM AUTHOR]

We report a detailed characterization of the thin film morphology of all-polymer blend devices by applying a combined analysis of physical, chemical, optical, and charge transport properties. This is exemplified by considering a model system comprising poly(3-hexylthiophene) (P3HT) and poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT). We show that the interactions between the two conjugated polymer components can be controlled by pre-forming the P3HT into highly ordered nanowire structures prior to blending with F8BT, and by varying the molecular weight of the F8BT. As a result, it is possible to produce films containing highly ordered P3HT with hole mobilities enhanced by three orders of magnitude over the pristine blends. Raman spectroscopy under resonant excitation conditions is used to probe the molecular order of both P3HT and F8BT phases within the blend films and these morphological studies are complemented by measurements of photocurrent generation. The resultant increase in photocurrent is associated with the enhanced charge carrier mobilities. The complementary analytical method demonstrated here is applicable to a wide range of polymer blend systems for all applications where the relationships between morphology and device performance are of interest. [ABSTRACT FROM AUTHOR]

This paper concerns the joint replenishment problem for a single buyer who sells multiple types of items to end customers. The buyer periodically replenishes the item inventory to order-up-to levels to cover the end customers' demands, which may be non-stationary. A joint replenishment policy characterized by a variable order-up-to level is proposed for buyers who wish to minimize the expected cost of operating the inventory system. According to the proposed policy, each period starts with calculation of the expected cost of two options, ordering and not ordering each item, based on a current inventory position and forecasted demand for the upcoming period. The proposed policy then uses an integer-programming model to generate a cost-minimizing decision for the joint replenishment. A computer experiment was performed to test the efficiency of the proposed policy. When compared with the most efficient policy currently available, our policy yielded considerable cost savings, especially for non-stationary demands. [ABSTRACT FROM AUTHOR]

In this study, an estimation method for human height is proposed using color and depth information. Color images are used for deep learning by mask R-CNN to detect a human body and a human head separately. If color images are not available for extracting the human body region due to low light environment, then the human body region is extracted by comparing between current frame in depth video and a pre-stored background depth image. The topmost point of the human head region is extracted as the top of the head and the bottommost point of the human body region as the bottom of the foot. The depth value of the head top-point is corrected to a pixel value that has high similarity to a neighboring pixel. The position of the body bottom-point is corrected by calculating a depth gradient between vertically adjacent pixels. Two head-top and foot-bottom points are converted into 3D real-world coordinates using depth information. Two real-world coordinates estimate human height by measuring a Euclidean distance. Estimation errors for human height are corrected as the average of accumulated heights. In experiment results, we achieve that the estimated errors of human height with a standing state are 0.7% and 2.2% when the human body region is extracted by mask R-CNN and the background depth image, respectively. [ABSTRACT FROM AUTHOR]

Irreversible chemical reactions are responsible for limited operational lifetime of organic light‐emitting devices (OLEDs). These reactions are triggered by highly reactive polaron pairs present in the emissive layer of OLEDs. Fast recombination of the polaron pairs is, therefore, crucial for slow degradation and high stability of OLED materials. Here, a study of the formation and annihilation of close polaron pairs in binary mixtures of wide bandgap hosts and a series of blue‐phosphorescent Ir(III) complex dopants, including two novel compounds, is reported. OLED devices containing doped light‐emitting layer are fabricated, and their operational lifetimes are estimated. Although inaccessible in solid films, charge recombination kinetics inside the polaron pairs is measured in liquid solutions using nanosecond laser flash photolysis. Multiscale computer simulations are applied to connect experimental results in different media and predict recombination rates in the device, with proper account taken of the inner‐ and outersphere reorganization in nonpolar materials. Predicted rates correlate with measured operational lifetimes, which demonstrates the key role of polaron pairs in the OLED degradation process. The developed methodology is useful for the rational design of novel OLED materials with higher efficiency and stability. [ABSTRACT FROM AUTHOR]

Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by progressive stenosis of large intracranial arteries and a hazy network of basal collaterals called moyamoya vessels. A polymorphism (R4810K) in the Ring Finger Protein 213 (RNF213) gene, at chromosome 17q25.3, is the strongest genetic susceptibility factor for MMD in East Asian populations. MMD was regarded prevalent in childhood and in East Asian populations. However, the so-called MMD could represent only the tip of the iceberg. MMD is increasingly reported in adult patients and in Western populations. Moreover, the RNF213 variant was recently reported to be associated with non-MMD disorders, such as intracranial atherosclerosis and systemic vasculopathy (e.g., peripheral pulmonary artery stenosis and renal artery stenosis). In this review, we summarize the spectrums of RNF213 vasculopathy in terms of clinical and genetic phenotypes. Continuous efforts are required for pathophysiology-based diagnoses and treatment, which will benefit from collaboration between clinicians and researchers, and between stroke and vascular physicians. [ABSTRACT FROM AUTHOR]

Background: Preterm birth (PTB) is a major adverse pregnancy outcome and largely contributes to increasing neonatal and maternal mortality. Genetic and environmental factors may play an important role in the development of PTB. Numerous studies have shown that immune genes related to the immune system, such as IL-6, IL-10, and TNFα, are associated with the occurrence of PTB. Objective: We examined genetic associations between IL-6 rs1800796, IL-10 rs1800872, and TNFα rs1800630 polymorphisms and PTB in Korean women. Methods: In this study, 115 PTB patients and 147 controls were analyzed. The genotyping of three SNPs was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: Our result showed that the rs1800872 polymorphism was significantly associated with the development of PTB in genotype frequency (odds ratio (OR) 1.71, 95% confidence interval (CI) 1.01–2.90, p = 0.046). We also found a significant association in an analysis of combined genotypes (rs1800796 CC, rs1800872 CA, and rs1800630 CA) (OR 7.43, 95% CI 2.06–26.84, p = 0.001). In a correlation analysis, rs1800630 A allele was significantly related with the increased birth weight (g) within PTB patients (p = 0.005). Conclusion: Our results imply possible relationships between the rs1800796, rs1800872, and rs1800630 polymorphisms and the development of PTB. [ABSTRACT FROM AUTHOR]

We present a deep learning solution to the prediction of particle production cross sections over a complicated, high-dimensional parameter space. We demonstrate the applicability by providing state-of-the-art predictions for the production of charginos and neutralinos at the Large Hadron Collider (LHC) at the next-to-leading order in the phenomenological MSSM-19 and explicitly demonstrate the performance for p p → χ ~ 1 + χ ~ 1 - , χ ~ 2 0 χ ~ 2 0 and χ ~ 2 0 χ ~ 1 ± as a proof of concept which will be extended to all SUSY electroweak pairs. We obtain errors that are lower than the uncertainty from scale and parton distribution functions with mean absolute percentage errors of well below 0.5 % allowing a safe inference at the next-to-leading order with inference times that improve the Monte Carlo integration procedures that have been available so far by a factor of O (10 7) from O (min) to O (μ s) per evaluation. [ABSTRACT FROM AUTHOR]

In this paper, a 25-kW bipolar pulsed-power supply for strategic mineral exploration has been described. A 500-V, 12.5-A unit module consisting of a highly efficient LCC resonant converter and a full-bridge-based bipolar pulse-switching unit is designed. The LCC resonant converter has a trapezoidal-shaped resonant current for reduced conduction loss. For achieving high power density, the leakage inductance of the transformer is used as resonant inductance without an external inductor. Moreover, the designed gate drive circuit based on the repetitive short pulse is proposed to operate the frequency range from dc to 8 kHz and reduce the size of the gate transformer. Four modules are connected in series and parallel in order to operate the power supply in either loop mode or grounded dipole mode. Depending on the load condition, the pulse power source capable of delivering the required high voltage and low current (2 kV, 12.5 A) or low voltage and high current (500 V, 50 A) is operated either in grounded dipole mode or loop mode, respectively. In order to satisfy the output voltage balancing of the four modules, the third wire is wound to compensate for the transformer of the LCC resonant converter. Finally, the design of the bipolar pulsed-power supply has been verified based on the experimental results of the field test. [ABSTRACT FROM AUTHOR]

This paper describes a bipolar pulsed power supply for strategic mineral exploration. Depending on the operating conditions, the bipolar pulsed power supply is capable of delivering the required high voltage and low current or low voltage and high current when operated, respectively, in either the grounded dipole mode or the loop mode. Based on a 500-V 12.5-A unit module, series and parallel connections of four modules are configured to satisfy both the grounded dipole mode (2000 V) and the loop mode (50 A), respectively. A unit module comprising an LCC resonant converter and a full-bridge-based bipolar pulse-switching unit is designed. In order to achieve high power density, the leakage inductance of the transformer is used as a resonant inductor in place of an external inductor. Accordingly, the resonant tank parameters are designed to give the resonant current a trapezoidal shape to reduce conduction loss and provide high efficiency. In addition, a simple gate-driving algorithm that uses the repetitive short pulse to cover the frequency range from dc to 8 kHz is proposed to allow the compact design of a minimized gate transformer. In this paper, the detailed design of the resonant circuit and the transformer of a unit module is described, and the operation is verified through simulation and experimental results. Finally, the developed LCC resonant converter achieves the maximum efficiency of 95%, the maximum power factor of 0.96, and a high power density of 806.5 W/L. [ABSTRACT FROM AUTHOR]

Polymer sorbents used for the removal of hexavalent chromium (Cr(VI)) ions from highly acidic aqueous media (pH≤1) are needed. In this study, micronsized polystyrene beads containing immobilized thiourea (mTA-PS) were prepared through suspension polymerization and two successive chemical modifications. The sorbent was stable even at pH of 0 under room temperature. The effects of pH, contact time, and initial concentration on sorption of Cr(VI) anions were studied. The isotherm data was fitted to the Freundlich model accordingly. The Langmuir model predicted the sorbent to have a maximum sorption capacity of 137 mg g−1 at pH 1. The sorbent exhibited a significant selective sorption of Cr(VI) ions over trivalent chromium (Cr(III)) ions. These results show that such polymer sorbent can be utilized to remove Cr(VI) ions from a highly acidic aqueous media. [ABSTRACT FROM AUTHOR]

This paper analyzes a logistics system involving a supplier who produces and delivers multiple types of items and a buyer who receives and sells to end customers. The buyer controls the inventory of each item by ordering at a preset time interval, which is an integer multiple of a base cycle, to meet the stochastic demands of the end customers. The supplier makes contracts with the buyer that specify that the ordered amount is delivered at the start of each period at a unit price determined by a quantity discount schedule. The contract also specifies that a buyer's order should exceed a minimum order quantity. To analyze the system, a mathematical model describing activities for replenishing a single type of item is developed from the buyer's perspective. An efficient method to determine the base cycle length and safety factor that minimizes the buyer's total cost is then proposed. The single item model is extended to a multiple items joint replenishment model, and algorithms for finding a cost-minimizing base cycle, order interval multipliers, and safety factors are proposed. The result of computational experiments shows that the algorithms can find near-optimal solutions to the problem. [ABSTRACT FROM AUTHOR]

Abstract: This paper considers a replenishment problem for a single buyer who orders multiple types of items from two or more heterogeneous suppliers in order to sell to end customers. The buyer periodically orders each type of item from the suppliers according to a select inventory control policy. Processing the order, each supplier enforces the policy that an order from the buyer must meet a predetermined minimum order quantity (MOQ). Therefore, the buyer must decide how much to order from each supplier considering the current inventory level, demand forecast, and MOQ requirement. The buyer's problem is formulated as an integer programming model and an efficient implementation strategy is suggested to apply the model to real problems. Numerical experiments are performed to test the validity of the proposed model as well as the efficiency of the implementation strategy. The experimental results show that this model combined with the implementation method yields a considerable cost reduction compared to the most efficient policy currently available. [ABSTRACT FROM AUTHOR]

Historically, much attention has been given to the unit processes and the integration of those unit processes to improve product yield. Less attention has been given to the wafer mini environment, either during processing or post processing. This paper contains a detailed discussion on how particles and airborne molecular contaminants (AMCs) from the wafer mini environment interact and produce undesired effects on the wafer which in turn cause devices to fail. Sources of wafer environmental contamination are the processes themselves, ambient environment, outgassing from wafers, and front open unified pod (FOUP) contamination. Establishing a strategy that reduces contamination inside the FOUP mini environment will decrease defect variability and thus increase yield. In manufacturing ecosystem, changing the FOUP or moving the wafers faster or purging with nitrogen to reduce the impact from mini environment is not always an option. Alternative to having a stop gap, it is desired to understand the AMCs and thus exploring sustainable solutions to minimize them below certain thresholds that would cause impact on wafer. NH3-based contamination, extensively discussed in this paper, is observed to cause wafer defects. Thus, explicit knowledge of AMC type is critical, as the most optimized methodology to control various AMCs might not always be the same. Three primary variables that greatly impact this strategy are FOUP contamination mitigation, FOUP material, FOUP metrology, and cleaning method. [ABSTRACT FROM AUTHOR]

Induction coil launcher (ICL) is an electromagnetic accelerator that uses Lorentz force to accelerate a projectile with a conducting armature. In this paper, the effects of the height and starting position of the armature on the performance of the ICL were analyzed. Launching experiments were conducted to verify the analysis results. The speed of the projectile converged to a saturated value as the armature height increased. We found that there exists an optimal starting position of the armature for the highest speed. The concept of inductance gradient was adopted to explain the analysis results. It was possible to predict the acceleration characteristics and to estimate the optimal starting position using this concept. Results show that the armature height should be longer than the drive coil height ( \textH\mathrm {coil}) , and the bottom of the armature should be positioned between (1/4)H\mathrm {coil} and (1/2)H\mathrm {coil} at the start to obtain the highest speed. The experimental results showed good agreement with the simulation analysis results. [ABSTRACT FROM AUTHOR]