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Tissue barriers in a body, well known as tissue-to-tissue interfaces represented by endothelium of the blood vessels or epithelium of organs, are essential for maintaining physiological homeostasis by regulating molecular and cellular transports. It is crucial for predicting drug response to understand physiology of tissue barriers through which drugs are absorbed, distributed, metabolized and excreted. Since the FDA Modernization Act 2.0, which prompts the inception of alternative technologies for animal models, tissue barrier chips, one of the applications of organ-on-a-chip or microphysiological system (MPS), have only recently been utilized in the context of drug development. Recent advancements in stem cell technology have brightened the prospects for the application of tissue barrier chips in personalized medicine. In past decade, designing and engineering these microfluidic devices, and demonstrating the ability to reconstitute tissue functions were main focus of this field. However, the field is now advancing to the next level of challenges: validating their utility in drug evaluation and creating personalized models using patient-derived cells. In this review, we briefly introduce key design parameters to develop functional tissue barrier chip, explore the remarkable recent progress in the field of tissue barrier chips and discuss future perspectives on realizing personalized medicine through the utilization of tissue barrier chips. [ABSTRACT FROM AUTHOR]

Cubic boron arsenide (BAs) is a subject of considerable interest in thermal science due to its exceptionally high thermal conductivity. However, the inherent long mean free path of phonons renders the thermal conductivity of BAs highly susceptible to impurity concentration. In this study, we present a catalyst assisted crystal synthesis approach to achieve high-quality cubic BAs, leveraging Pt as a catalyst in the synthesis process. Our thermal conductivity measurements reveal that over 90% of the samples in a batch exhibit thermal conductivity values exceeding 1000 W·m−1·K−1. The robustness of the synthesis method is further validated through thermal conductivity mapping and Raman spectroscopy. These findings offer valuable insights for enhancing the quality of BAs crystals and hold promise for practical applications. [ABSTRACT FROM AUTHOR]

For safe coexistence between robots and humans, it is important for robots to detect the presence of nearby humans as well as any physical contacts made to its body. The design of a modular textile sensor array and an algorithm for multi‐modal sensing of human touches and other contacts with their contact forces proposed. Each sensor module in the array is capable of multi‐modal sensing, and the entire array with multiple modules requires only two wires to read the outputs from all the modules using band‐stop filter circuits. The proposed sensor system shows the structural modularity, achieved by simple fabrication of sequential lamination of conductive and non‐conductive textile materials, realizing electrical connections through conductive snap buttons that connect the modules to the circuit. The functional modularity is also achieved through the compensation algorithm, derived from the analysis of the transfer function in the frequency domain. The algorithm significantly reduces signal interferences between modules. The multi‐modality, the textile‐based design, and the structural and functional modularity of the proposed system enable practical applications to various robotic systems, including robotic skin for a collaborative robot, a wearable sensor, a robot hand sensor, and a human–computer interface, as demonstrated in this study. [ABSTRACT FROM AUTHOR]

Since the invention of transistors and integrated circuits, the development of semiconductor processes has advanced rapidly. Current microchips contain hundreds of millions of transistors. The remarkable development of semiconductors thus far has also led to difficulties in designing tightly packed lithography patterns without unwanted defects called hotspots in the manufacturing process. Therefore, research areas focusing on these problems have received much attention. In particular, predicting hotspots during the design stage is essential for high productivity in the semiconductor industry. In this study, we developed a deep learning-based SEM image generation model to predict hotspots from layout patterns at the design stage. Our model combines a segmentation network and an image-to-image translation network based on a conditional generative adversarial network in parallel. Our proposed model can predict and display potential hotspots in scanning electron microscopy images generated from given layouts. Additionally, the model leverages prior knowledge of the optical diameter to predict patterns that are prone to hotspots. Our model shows improved performance over baseline models when evaluated on real-world industrial data. [ABSTRACT FROM AUTHOR]

Helly's theorem and its variants show that for a family of convex sets in Euclidean space, local intersection patterns influence global intersection patterns. A classical result of Eckhoff in 1988 provided an optimal fractional Helly theorem for axis-aligned boxes, which are Cartesian products of line segments. Answering a question raised by Bárány and Kalai, and independently Lew, we generalize Eckhoff's result to Cartesian products of convex sets in all dimensions. In particular, we prove that given α ∈ (1 - 1 / t d , 1 ] and a finite family F of Cartesian products of convex sets ∏ i ∈ [ t ] A i in R td with A i ⊂ R d , if at least α -fraction of the (d + 1) -tuples in F are intersecting, then at least (1 - (t d (1 - α)) 1 / (d + 1)) -fraction of sets in F are intersecting. This is a special case of a more general result on intersections of d-Leray complexes. We also provide a construction showing that our result on d-Leray complexes is optimal. Interestingly, the extremal example is representable as a family of Cartesian products of convex sets, implying that the bound α > 1 - 1 / t d and the fraction (1 - (t d (1 - α)) 1 / (d + 1)) above are also best possible. The well-known optimal construction for fractional Helly theorem for convex sets in R d does not have (p , d + 1) -condition for sublinear p, that is, it contains a linear-size subfamily with no intersecting (d + 1) -tuple. Inspired by this, we give constructions showing that, somewhat surprisingly, imposing an additional (p , d + 1) -condition has a negligible effect on improving the quantitative bounds in neither the fractional Helly theorem for convex sets nor Cartesian products of convex sets. Our constructions offer a rich family of distinct extremal configurations for fractional Helly theorem, implying in a sense that the optimal bound is stable. [ABSTRACT FROM AUTHOR]

Herein, we report our findings on 4-carbazole (CBZ)-appended salen-based indium complexes, CBZIn1 and CBZIn2, which feature diimine bridges exhibiting different electron-accepting properties. Notably, CBZIn2 exhibited a significantly higher photoluminescence quantum efficiency (PLQY, ΦPL) in toluene than CBZIn1, with a value over 15 times greater (ΦPL = 57.7% for CBZIn2; ΦPL = 3.7% for CBZIn1). In particular, in the rigid state of THF at 77 K, CBZIn2 exhibited a near-unity PLQY of 98.2%. Even in the PMMA film, CBZIn2 maintained a high level of PLQY (ΦPL = 70.2%). These results can be attributed to the highly efficient radiative decay process based on intramolecular charge-transfer (ICT) transition between the moderately twisted CBZ, characterized by its conformational rigidity and the 1,2-dicyanoethylene-bridged salen, which exhibits a strong electron-accepting ability. Furthermore, these findings are supported by theoretical calculations. [ABSTRACT FROM AUTHOR]

Electrochemical CO production from CO2 electrolysis has been considered the most economically viable approach among various candidate products. AuCu bimetallic alloys are currently receiving attention for their potential to tailor catalytic activity. Here, we synthesized a dilute AuCu alloy nanostructure with an AuCu atomic composition ratio of 3% by using a simple electrochemical treatment method on a 200 nm-thick Au thin film. The dilute AuCu alloy catalyst shows an exceptional CO2 reduction activity in terms of selectivity and overpotential for CO production. In addition, the stability property is more significantly enhanced as compared to pure Au nanostructures. In addition, we describe an in situ tailoring method of catalytic activity for Au nanostructures by repeating an electrochemical treatment process that is performed for forming the Au nanostructure. This approach will be a promising and facile strategy not only for reactive Au catalysts but also to increase the stability activity simultaneously by utilizing Cu impurities existing in an aqueous electrolyte for CO2 reduction. [ABSTRACT FROM AUTHOR]

In vitro investigation of a glomerular filtration barrier (GFB) remains difficult because of the inability to mimic its specialized structure, although various kidney diseases are characterized by GFB dysfunction. Here, the development of a microfluidic model that replicates the physiology of the GFB has been achieved by tunable glomerular basement membrane (gBM) deposition and 3D co-culture of podocytes with glomerular endothelial cells (gECs). By precisely controlling the thickness of the gBM, our model successfully reproduced the biphasic response of the GFB, where variations in gBM thickness influence barrier properties. Moreover, this microscale proximity of gECs and podocytes facilitated their dynamic crosstalk, which is essential for maintaining the integrity and function of the GFB. We observed that addition of gBM and podocytes enhanced barrier function of gECs by inducing up-regulation of gEC's tight junctions synergistically, and moreover, found an ultrastructure of gECs–gBM–podocytes' foot process contacting each other by confocal and TEM imaging. The dynamic interaction of gECs and podocytes played a significant role in the response to drug-induced injury and the regulation of barrier properties. Nephrotoxic injury simulated in our model helped to elucidate that the over-production of vascular endothelial growth factor A from the injured podocytes mediates GFB impairment. We believe that our GFB model can provide a valuable tool for mechanistic studies such as investigating GFB biology, comprehending disease mechanisms, and evaluating potential therapeutic approaches in a controlled and physiologically relevant environment. [ABSTRACT FROM AUTHOR]

Microphysiological system or organ-on-a-chip technologies can replicate the key structure and function of 3D human tissues with higher reproducibility than less controllable 3D cell aggregate models, providing great potential to become advanced drug toxicity and efficacy test platforms alternative to animal models. However, these organ chip models remain to be manufactured and standardized in a highly reproducible manner for reliable drug screening and mechanism of action research. Herein, we present a manufactured form of 'micro-engineered physiological system-tissue barrier chip' called MEPS-TBC for the highly replicable modeling of the human blood–brain barrier (BBB) with a 3D perivascular space. The perivascular region was controlled by tunable aspiration, where human astrocytes reside in 3D, create a network, and communicate with human pericytes facing human vascular endothelial cells, thereby replicating the 3D BBB. The lower channel structure of MEPS-TBC was designed and optimized using a computational simulation to facilitate aspiration while maintaining multicellular construction. Our human BBB model of the 3D perivascular unit and the endothelium perfused by physiological shear stress secured significantly enhanced barrier function exhibiting greater TEER and lower permeability, compared to the only endothelial model, indicating that the cellular interactions between BBB cells significantly contribute to the BBB formation. Importantly, our BBB model showed the cellular barrier function for homeostatic trafficking regulation against inflammatory peripheral immune cells, as well as for molecular transport control across the BBB. We believe our manufactured chip technology will construct reliable and standardized organ-chip models for disease mechanism research and predictive drug screening. [ABSTRACT FROM AUTHOR]

Daphnia magna is an important organism in ecotoxicity studies because it is sensitive to toxic substances and easy to culture in laboratory conditions. Its locomotory responses as a biomarker are highlighted in many studies. Over the last several years, multiple high-throughput video tracking systems have been developed to measure the locomotory responses of Daphnia magna. These high-throughput systems, used for high-speed analysis of multiple organisms, are essential for efficiently testing ecotoxicity. However, existing systems are lacking in speed and accuracy. Specifically, speed is affected in the biomarker detection stage. This study aimed to develop a faster and better high-throughput video tracking system using machine learning methods. The video tracking system consisted of a constant temperature module, natural pseudo-light, multi-flow cell, and an imaging camera for recording videos. To measure Daphnia magna movements, we developed a tracking algorithm for automatic background subtraction using k-means clustering, Daphnia classification using machine learning methods (random forest and support vector machine), and tracking each Daphnia magna location using the simple online real-time tracking algorithm. The proposed tracking system with random forest performed the best in terms of identification (ID) precision, ID recall, ID F1 measure, and ID switches, with scores of 79.64%, 80.63%, 78.73%, and 16, respectively. Moreover, it was faster than existing tracking systems such as Lolitrack and Ctrax. We conducted an experiment to observe the impact of toxicants on behavioral responses. Toxicity was measured manually in the laboratory and automatically using the high-throughput video tracking system. The median effective concentration of Potassium dichromate measured in the laboratory and using the device was 1.519 and 1.414, respectively. Both measurements conformed to the guideline provided by the Environmental Protection Agency of the United States; therefore, our method can be used for water quality monitoring. Finally, we observed Daphnia magna behavioral responses in different concentrations after 0, 12, 18, and 24 h and found that there was a difference in movement according to the concentration at all hours. [ABSTRACT FROM AUTHOR]

With the development of deep learning technology, deep reinforcement learning (DRL) has successfully built intelligent agents in sequential decision-making problems through interaction with image-based environments. However, learning from unlimited interaction is impractical and sample inefficient because training an agent requires many trial and error and numerous samples. One response to this problem is sample-efficient DRL, a research area that encourages learning effective state representations in limited interactions with image-based environments. Previous methods could effectively surpass human performance by training an RL agent using self-supervised learning and data augmentation to learn good state representations from a given interaction. However, most of the existing methods only consider similarity of image observations so that they are hard to capture semantic representations. To address these challenges, we propose spatio-temporal and action-based contrastive representation (STACoRe) learning for sample-efficient DRL. STACoRe performs two contrastive learning to learn proper state representations. One uses the agent's actions as pseudo labels, and the other uses spatio-temporal information. In particular, when performing the action-based contrastive learning, we propose a method that automatically selects data augmentation techniques suitable for each environment for stable model training. We train the model by simultaneously optimizing an action-based contrastive loss function and spatio-temporal contrastive loss functions in an end-to-end manner. This leads to improving sample efficiency for DRL. We use 26 benchmark games in Atari 2600 whose environment interaction is limited to only 100k steps. The experimental results confirm that our method is more sample efficient than existing methods. The code is available at https://github.com/dudwojae/STACoRe. • Contrastive learning using the agent's actions as pseudo labels improves sample efficiency. • Automatically selecting the optimal data augmentation improves training stability. • Contrastive learning using spatio-temporal information further improves sample efficiency. [ABSTRACT FROM AUTHOR]

We study regular graphs in which the random walks starting from a positive fraction of vertices have small mixing time. We prove that any such graph is virtually an expander and has no small separator. This answers a question of Pak [ SODA: Proceedings of the Thirteenth Annual ACM-SIAM Symposium on Discrete Algorithms, Society for Industrial and Applied Mathematics , Philadelphia, PA, 2002, pp. 321–328]. As a corollary, it shows that sparse (constant degree) regular graphs with many well-mixing vertices have a long cycle, improving a result of Pak. Furthermore, such cycle can be found in polynomial time. Secondly, we show that if the random walks from a positive fraction of vertices are well-mixing, then the random walks from almost all vertices are well-mixing (with a slightly worse mixing time). [ABSTRACT FROM AUTHOR]

Deep reinforcement learning (DRL) has shown remarkable capabilities in solving sequential decision-making problems. However, DRL requires extensive interactions with image-based environments. Existing methods have combined self-supervised learning or data augmentation to improve sample efficiency. While understanding the temporal information dynamics of the environment is important for effective learning, many methods do not consider these factors. To address the sample efficiency problem, we propose dynamics modeling with sequential temporal information (DynaSTI) that incorporates environmental dynamics and leverages the correlation among trajectories to improve sample efficiency. DynaSTI uses an effective learning strategy for state representation as an auxiliary task, using gated recurrent units to capture temporal information. It also integrates forward and inverse dynamics modeling in a hierarchical configuration, enhancing the learning of environmental dynamics compared to using each model separately. The hierarchical structure of DynaSTI enhances the stability of inverse dynamics modeling during training by using inputs derived from forward dynamics modeling, which focuses on feature extraction related to controllable state. This approach effectively filters out noisy information. Consequently, using denoised inputs from forward dynamics modeling results in improved stability when training inverse dynamics modeling, rather than using inputs directly from the encoder. We demonstrate the effectiveness of DynaSTI through experiments on the Atari game benchmark, limiting the environment interactions to 100k steps. Our extensive experiments confirm that DynaSTI significantly improves the sample efficiency of DRL, outperforming comparison methods in terms of statistically reliable metrics and nearing human-level performance. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to introduce a new surgical technique for pedicled TRAM flap that removes a part of the rectus abdominis muscle inserting into ribs, and to analyze this technique in comparison with classical pedicled TRAM flap. Methods: A retrospective review of patient charts from May 2006 to February 2016 was performed. The patient group that underwent the removal of the part of the rectus abdominis that inserts into the thorax (partial muscle resection; PMR group) was compared with the group that did not undergo this muscle resection (Classical group). The complications and aesthetic effects of surgery between the two groups were analyzed. Results: There were 34 patients in the classical group and 28 in the PMR group. There were no significant differences in postoperative complications between these two groups. The rates of fat necrosis were 32.1% in the PMR group and 36.1% in the classical group. The postoperative aesthetic outcome of the inframammary fold showed no significant differences in outcome between the classical and PMR groups. However, all items received higher scores in the PMR group. Conclusions: The authors' new surgical method was associated with a positive cosmetic effect of improving inframammary fold aesthetics and could thus represent a new option for pTRAM breast reconstruction. [ABSTRACT FROM AUTHOR]

We prove an asymptotically tight bound on the extremal density guaranteeing subdivisions of bounded-degree bipartite graphs with a mild separability condition. As corollaries, we answer several questions of Reed and Wood on embedding sparse minors. Among others, • average degree is sufficient to force the grid as a topological minor; • average degree forces every -vertex planar graph as a minor, and the constant is optimal, furthermore, surprisingly, the value is the same for -vertex graphs embeddable on any fixed surface; • a universal bound of on average degree forcing every -vertex graph in any nontrivial minor-closed family as a minor, and the constant 2 is best possible by considering graphs with given treewidth. [ABSTRACT FROM AUTHOR]

This article studies low-temperature sol–gel processed indium (In)-doped ZnO (IZO) for highly efficient organic photovoltaics (OPVs). Contrary to the prior research trends adopting doped sol–gel processed ZnO with an annealing temperature of over 400 °C for the hydrolysis reaction, IZO with an annealing temperature of 200 °C is studied. Similar to the high-temperature solvent system, it is elucidated that low-temperature sol–gel processed IZO effectively improves the performance of OPVs, increasing the power conversion efficiency from 6.80% to 7.35%. For further analyses, the current–voltage (J–V) characteristics and ideality factors (n) are examined as a function of In doping ratios, which revealed that In doping on ZnO effectively reduces trap-assisted recombination within devices. [ABSTRACT FROM AUTHOR]

Building-integrated photovoltaics (BIPVs) are gaining recognition in urban settings for overcoming spatial constraints and enabling photovoltaic (PV) power generation. However, the dark appearance of traditional PV modules often hinders aesthetic integration and market adoption. To address this issue, research has focused on colored photovoltaic modules (CPMs) using a luminescent down-shifting layer (LDS) with high color purity and a broad color range. Despite advancements, most previous studies have focused on experimental implications, while the theoretical efficiency limits of LDS-based CPMs remain underexplored. The present manuscript aims to bridge this gap by elucidating the correlation between the optical characteristics of LDS-based CPMs and their desired color attributes, utilizing the Natural Color System (NCS) and CIELAB color space to rigorously explore the influence of color characteristics perceived by human observers. Furthermore, this study conducts a comprehensive evaluation of CPM performance across various module types, offering new insights into the field of BIPVs and providing valuable perspectives for their efficient and aesthetic integration into urban landscapes. [Display omitted] • Colored photovoltaic modules with a luminescent down-shifting layer present promising solutions for building-integrated photovoltaics. • This study examines the influence of photovoltaic module types on the performance and coloration of CPMs featuring an LDS. • Optimal performance is associated with a broad internal quantum efficiency spectrum extending beyond 1100 nm and with lower values below 350 nm. • Evaluation using the Natural Color System highlights hues such as Y and R80B as less efficient due to the broad photoluminescent emission of an LDS. • The efficiency of CPMs notably declines with higher CIELAB L ∗ values, emphasizing the importance of adjusting colors with L ∗ <60. [ABSTRACT FROM AUTHOR]

The magnesiothermic reduction of SiO 2 to Si is a promising route for preparing high-energy-density Si-based anode materials for lithium-ion batteries. However, the effect of the initial morphological properties of SiO 2 on the electrochemical performance of Si remains unclear. Herein, porous Si (PSi) particles were prepared from four different SiO 2 precursors, namely, spherical SiO 2 particles with diameters of 0.3 and 20 μm (denoted SiO 2 -0.3 and SiO 2 -20, respectively), fumed SiO 2 powder (denoted SiO 2 -F), and well-ordered mesoporous SiO 2 particles (denoted SiO 2 -K). Highly crystalline PSi particles were obtained after magnesiothermic reduction and subsequent HCl and HF etching. PSi prepared from SiO 2 -0.3 maintained its precursor morphology to some extent, whereas highly irregular Si particles were produced from SiO 2 -20, SiO 2 -F, and SiO 2 -K. Among the PSi particles, those prepared from SiO 2 -0.3 delivered the highest reversible capacity (1427 mAh g–1 at 0.1 A g–1) after 50 discharge–charge cycles. Because of the unique hierarchically porous morphology of PSi prepared from SiO 2 -0.3, the expansion of its electrode thickness was suppressed below 140 %. Moreover, owing to its nanosized Si domains and good electrode wetting, PSi prepared from SiO 2 -0.3 demonstrated improved electrochemical properties compared with those prepared from SiO 2 -F and SiO 2 -K. [Display omitted] • Porous Si (PSi) was synthesized via modified magnesiothermic reduction using NaCl. • Effect of SiO 2 precursors on electrochemical performance of PSi was investigated. • PSi from 0.3 μm SiO 2 maintained its precursor morphology after acid leaching. • PSi from 0.3 μm SiO 2 exhibited highest capacity (1427 mAh g–1 at 0.1 A g–1). [ABSTRACT FROM AUTHOR]

Biosignals provide information about the onset of certain diseases or health conditions, aiding in diagnosing diseases and monitoring health conditions quickly and accurately. However, the inter-subject variability within biosignals hampers the model performance. In this study, we propose an inter-subject similar loss to learn representations robust to inter-subject variability. This loss promotes subject invariance, improves the generalizability of the representation, and allows better representations to be learned even with fewer training subjects. The proposed framework consists of two complementary loss functions: (1) supervised contrastive loss and (2) inter-subject similar loss. We evaluated the classification performance of the proposed method on three public biosignal datasets. The experimental results demonstrate that the proposed method outperforms the comparison methods and that the subject-invariant representation performs well on unseen subjects. Code is available at: https://github.com/KimHyeon-Ji/CSGR-Bio.git [ABSTRACT FROM AUTHOR]

Summary: Halide perovskite solar cells (PSCs) have gained enormous attention due to their favorable features such as bandgap tunability, considerable free carrier diffusion length, low‐cost fabrication, and comparable efficiency to that of conventional silicon solar cells. Among several PSCs' structures, the inverted structure is the most suitable candidate for diverse portable applications since they can take advantage of the previously developed organic solar cells' structure. However, the single transporting layer system of the inverted‐structured PSCs makes it challenging to achieve high efficiency and operational stability. Here, we introduce a unique transporting layer system that adopts 8‐hydroxyquinolinolato‐lithium (Liq) as a buffer layer at the interface between [6,6]‐phenyl C71 butyric acid methyl ester (PC70BM) and Ag electrode. By introducing the Liq, we effectively decreased the potential energy barrier and iodide accumulation at the interface between PC70BM and Ag electrode, which resulted in an efficient and stable PSC. In the optimized structure, the power conversion efficiency and stability (T80) increased from 9.5% and 100 h to 10.13% and 200 h, respectively. [ABSTRACT FROM AUTHOR]

In 1975, Erdős asked the following question: what is the smallest function f(n) for which all graphs with n vertices and f(n) edges contain two edge-disjoint cycles C_1 and C_2, such that the vertex set of C_2 is a subset of the vertex set of C_1 and their cyclic orderings of the vertices respect each other? We prove the optimal linear bound f(n)=O(n) using sublinear expanders. [ABSTRACT FROM AUTHOR]

In 1972, Cvetković proved that if G is an n -vertex simple graph with the chromatic number k , then its spectral radius is at most the spectral radius of the n -vertex balanced complete k -partite graph. In this paper, we analyze the characteristic polynomial of a digraph D to prove a tight upper bound for the spectral radius of D in terms of the number of vertices and the chromatic number of D ; we also characterize when equality holds. This provides a simple proof of a result by Lin and Shu [6]. [ABSTRACT FROM AUTHOR]

Here, we report the results of experiments regarding the chemical repositioning of 4‐(2‐hydroxyethyl)‐1‐piperazine ethane sulfonic acid (HEPES), a representative buffering agent. In this work, we confirmed that HEPES could disaggregate amyloid plaques, a hallmark of Alzheimer's disease, and we verified its sustained‐release system (release for up to 2 weeks) via hybridization with a biocompatible polymer (Eudragit S100). [ABSTRACT FROM AUTHOR]

Polymer light-emitting diodes (PLEDs) possess several unique advantages over competitive technologies, including solution processability, broad applicability, and low-cost fabrication. However, their commercialization is delayed due to the relatively low operation stability compared to current display techniques. To provide fundamental insight into the degradation mechanism and enhance the stability, we discuss unique analysis methods of PLEDs' degradation using photovoltaic impedance characteristics. In particular, we report the method to determine the energetic disorder or density of states (DOS) of PLEDs using light intensity (Plight)-dependent open-circuit voltage (VOC) and Cole–Cole plot measurement. Based on the method, it was found that PLED degradation results in a shift of the center of DOS rather than broadening. Furthermore, we extrapolated equivalent ideality factor (n) values from the Plight-dependent VOC and dark current density–voltage (J–V) characteristics, which implied trap-assisted recombination throughout the degradation process. Thus, we believe that the results will provide helpful and comprehensive insight into understanding the degradation of PLEDs. [ABSTRACT FROM AUTHOR]

This study aimed to identify the specific vaccine strain associated with herpes zoster (HZ) in children following a series of diagnosed cases and to explore whether differences in single nucleotide polymorphisms (SNPs) among various vaccine strains are linked to an increased incidence of herpes zoster after vaccination. From February 2021 to March 2024, children <12 years old suspected of vaccine-related varicella-like rash or HZ were included. Varicella zoster virus DNA isolated from the patients were sequenced to differentiate vaccine type versus wild-type. 3D protein structures of pORF62 were simulated using open reading frame 62 sequences extracted from whole genome sequencing of vOka, MAV/06, Oka/SK vaccines, and pOka reference. A total of 27 children with a median age of 2.1 (interquartile range, 1.5–3.4) years old presented with vaccine-related varicella-like rash (n = 4/27, 14.8%) or HZ (n = 23/27, 85.2%). One patient with varicella-like rash and 34.8% (n = 8/23) with HZ had disseminated skin involvement. All were immunized with the Oka/SK strain varicella vaccine. Genotyping showed 88.2% (n = 15/17) had SNPs specific to the Oka/SK strain, and two had SNPs considered pOka type contained within the Oka/SK vaccine. Despite accumulations of SNPs in ORF 62 of Oka/SK, the translated amino acid sequence and 3D protein structure were identical to wild-type pOka's pORF62. In vOKA and MAV/06, changes in amino acids occurred at two positions, S628G and R958G, within pORF62. The predicted 3D protein structure of vOka and MAV/06's pORF62 showed that the α helical structure within region I undergoes conformational change, potentially increasing difficulties in interactions with infection-related proteins and thereby decreasing virulence. pORF62 in pOka and Oka/SK exhibited more stable structure complex of the α helical structure. Lack of structural alternations in region I of pORF62 due to the absence of critical genetic polymorphisms in open reading frame 62 could be associated with the heightened incidence of adverse events. [ABSTRACT FROM AUTHOR]

Detecting defects in the inspection stage of semiconductor manufacturing process is a crucial task to improve yield and productivity as well as wafer quality. Recent Advances in semiconductor process technology have greatly increased the transistor density. As a result, an increasingly high number of defects inevitably emerge and we need a more accurate and efficient detection method to manage them. In this paper, we propose a deep-learning-based defect detection model to expedite the process. It adopts an adversarial network architecture of conditional GAN. The discriminator of an adversarial network architecture helps the detection model learn to detect and classify defects accurately. The high performance is achieved by using Focal Loss, PixelGAN and multi-scale level features, which is shown to be better than the baseline model, CenterNet, when tested for a real industrial dataset. [ABSTRACT FROM AUTHOR]

This article introduces an augmented adaptive unscented Kalman filter (KF). The proposed novel technique is suitable to simultaneously estimate both the diagonal process noise covariance matrix and the unknown inputs, thus combining previously reported KF estimators for unknown inputs (dual or joint KF) and for covariance matrices (adaptive KF). A selective scaling method is also introduced to improve the convergence property of the suggested KF. The development of the novel KF is also motivated by a specific estimation problem related to crane systems. Cranes represent a special class of weight handling equipment as they are underactuated and described by nonlinear dynamics such that the load present oscillatory behavior. In addition to the increasing need for their automation in various industrial fields, these features also make them a benchmark system in control engineering with numerous control laws reported in the literature for sway elimination and trajectory tracking. A common issue to realize most of the advanced control laws on real, eventually industrial size cranes is the necessity to know the sway angle and frictions on the configuration variables. It is shown in simulation and also with real experiments on a reduced size overhead crane system that the suggested KF is suitable to estimate both the sway angles and the frictions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recent advances in multifunctional therapeutic materials for cancer treatment are summarized. • A general overview of cancer treatment using light, ultrasound, and light-/ultrasound-induced immune system are briefed. • Promising strategies and prospects for next-generation therapeutic materials are presented. Cancer is one of the most formidable diseases in modern society, and cancer treatment is facing a new phase. Alongside traditional methods such as chemotherapy, various practical adjuvant therapeutic approaches and related agents have been introduced to enhance the chances of a cure and reduce the recurrence of cancers. Notably, non-invasive external source-based therapeutic approaches, agents (sensitizers), and cancer-specific delivery materials using light (phototherapy), ultrasound, and light-/ultrasound-induced immune response have garnered widespread attention: (i) Photo: photodynamic therapy (PDT), photothermal therapy (PTT), (ii) Ultrasound: sonodynamic therapy (SDT), and (iii) Immune response: light-/ultrasound-induced immunotherapy (IMT). However, the application of the individual approach to cancer therapy exhibits some disadvantages and limitations despite their potential for developing a cure. In this comprehensive review, we have systematically summarized recent literature, focusing on the recent advances in multifunctional therapeutic materials, such as dual-functional, triple-functional, and all-in-one materials. We hope this review will inspire the development of next-generation multifunctional cancer therapeutic materials and thereby contribute to enhancing global health conditions. [ABSTRACT FROM AUTHOR]

Honeybees play a crucial role in the agriculture industry because they pollinate approximately 75% of all flowering crops. However, every year, the number of honeybees continues to decrease. Consequently, numerous researchers in various fields have persistently attempted to solve this problem. Acoustic scene classification, using sounds recorded from beehives, is an approach that can be applied to detect changes inside beehives. This method can be used to determine intervals that threaten a beehive. Currently, studies on sound analysis, using deep learning algorithms integrated with various data preprocessing methods that extract features from sound signals, continue to be conducted. However, there is little insight into how deep learning algorithms recognize audio scenes, as demonstrated by studies on image recognition. Therefore, in this study, we used a mel spectrogram, mel-frequency cepstral coefficients (MFCCs), and a constant-Q transform to compare the performance of conventional machine learning models to that of convolutional neural network (CNN) models. We used the support vector machine, random forest, extreme gradient boosting, shallow CNN, and VGG-13 models. Using gradient-weighted class activation mapping (Grad-CAM), we conducted an analysis to determine how the best-performing CNN model recognized audio scenes. The results showed that the VGG-13 model, using MFCCs as input data, demonstrated the best accuracy (91.93%). Additionally, based on the precision, recall, and F1-score for each class, we established that sounds other than those from bees were effectively recognized. Further, we conducted an analysis to determine the MFCCs that are important for classification through the visualizations obtained by applying Grad-CAM to the VGG-13 model. We believe that our findings can be used to develop a monitoring system that can consistently detect abnormal conditions in beehives early by classifying the sounds inside beehives. [ABSTRACT FROM AUTHOR]

The extremal number ex (n , F) of a graph F is the maximum number of edges in an n -vertex graph not containing F as a subgraph. A real number r ∈ [ 1 , 2 ] is realisable if there exists a graph F with ex (n , F) = Θ (n r). Several decades ago, Erdős and Simonovits conjectured that every rational number in [ 1 , 2 ] is realisable. Despite decades of effort, the only known realisable numbers are 0 , 1 , 7 5 , 2 , and the numbers of the form 1 + 1 m , 2 − 1 m , 2 − 2 m for integers m ≥ 1. In particular, it is not even known whether the set of all realisable numbers contains a single limit point other than the two numbers 1 and 2. In this paper, we make progress on the conjecture of Erdős and Simonovits. First, we show that 2 − a b is realisable for any integers a , b ≥ 1 with b > a and b ≡ ± 1 (mod a). This includes all previously known ones, and gives infinitely many limit points 2 − 1 m in the set of all realisable numbers as a consequence. Secondly, we propose a conjecture on subdivisions of bipartite graphs. Apart from being interesting on its own, we show that, somewhat surprisingly, this subdivision conjecture in fact implies that every rational number between 1 and 2 is realisable. [ABSTRACT FROM AUTHOR]

The stable performance of organic solar cells (OSCs) at high temperatures is a critical issue for their commercialization. Although a few studies have reported the improved stability of OSCs that adopted Al-doped ZnO (AZO) as an electron transport layer (ETL), systematic research that validates the origins of this improvement has been lacking. In this work, we investigated the underlying mechanism for the improved stability of an OSC with AZO. By adopting AZO, the power conversion efficiency reached 8.65% and retained 70% of its initial value at 85 °C for 6 h, which was an increase in stability of 46% compared to that of an OSC with pristine ZnO. We found that the improved stability of the OSC with AZO originated from the decrease in oxygen defects and the space-charge limited current region through trap-related analyses and the Mott-Gurney law. Therefore, the results supported the enhanced thermal stability of OSCs that incorporated AZO as an ETL. [ABSTRACT FROM AUTHOR]

The G-protein signaling pathway plays a key role in multiple cellular processes and is well conserved in eukaryotes. Although GIPC (G-protein α subunit interacting protein (GAIP)-interacting protein, C terminus) has been studied in several model organisms, little is known about its role in Caenorhabditis elegans. In the present study, we investigated the roles of gipc-1 and gipc-2 in C. elegans. We observed that they were exclusively expressed in sperm throughout the development and that gipc-1; gipc-2 double mutants were infertile. Further examination of sperm development in gipc-1; gipc-2 mutants revealed defective sperm activation and abnormal pseudopod extension that resulted in reduced sperm motility. Moreover, major sperm protein (MSP) was abnormally segregated between spermatids and residual bodies in gipc-1; gipc-2 mutants. Our findings indicate that gipc-1 and gipc-2 are required for the proper pseudopod extension of sperm during the terminal differentiation of spermatids. During this process, the segregation of MSP into spermatids is important for ensuring normal sperm motility during fertilization. • gipc-1 and gipc-2 are required for male fertility in Caenorhabditis elegans. • GIPC is involved in the segregation of major sperm proteins in spermatids. • GIPC is essential for sperm motility and migration. [ABSTRACT FROM AUTHOR]

We prove that every strongly 10 50 t -connected tournament contains all possible 1-factors with at most t components and this is best possible up to constant. In addition, we can ensure that each cycle in the 1-factor contains a prescribed vertex. This answers a question by Kühn, Osthus, and Townsend. Indeed, we prove more results on partitioning tournaments. We prove that a strongly Ω (k 4 t q) -connected tournament admits a vertex partition into t strongly k -connected tournaments with prescribed sizes such that each tournament contains q prescribed vertices, provided that the prescribed sizes are Ω (n). This result improves the earlier result of Kühn, Osthus, and Townsend. We also prove that for a strongly Ω (t) -connected n -vertex tournament T and given 2 t distinct vertices x 1 , ... , x t , y 1 , ... , y t of T , we can find t vertex disjoint paths P 1 , ... , P t such that each path P i connecting x i and y i has the prescribed length, provided that the prescribed lengths are Ω (n). For both results, the condition of connectivity being linear in t is best possible, and the condition of prescribed sizes being Ω (n) is also best possible. [ABSTRACT FROM AUTHOR]

The conversion of CO2 into fuels and value-added chemicals over heterogeneous catalysts may help realize a carbon-neutral or carbon-negative society. Recently, the direct conversion of CO2 to aromatics has been extensively explored. However, the requirement of multifunctional active sites, complexity of tandem cascade reactions, and difficulty in understanding reaction mechanisms present significant challenges to the design of effective heterogeneous catalysts. In this review, catalytic systems used for the direct production of aromatics from CO2 via the methanol-mediated and modified Fischer–Tropsch synthesis pathways are critically discussed. The initial section discusses the role of acid sites in HZSM-5 for the formation of aromatics. This is followed by a thorough review of recent progress on aromatic syntheses in terms of their catalytic performance, Si/Al ratios of zeolites, proximity between metal oxide and zeolite, and reaction conditions. The reaction mechanisms and the stability of existing catalysts are also discussed. Finally, the current challenges and future prospects of the catalytic conversion of CO2 to aromatics are highlighted. [ABSTRACT FROM AUTHOR]

We prove upper bounds for the spectral radius ρ (G) of an n -vertex graph with given maximum degree and girth at least 2 ℓ + 1. This extends the previous result of [9] regarding graphs with girth at least five. When ℓ = 3 or | V (G) | is relatively small compared with the maximum degree, our upper bounds are sharp. In addition, for a tree T , we provide an upper bound for the spectral radius of an n -vertex T -free graph with given maximum degree. This bound is also sharp for a certain class of trees. [ABSTRACT FROM AUTHOR]

Let f^{(r)}(n;s,k) be the maximum number of edges of an r-uniform hypergraph on n vertices not containing a subgraph with k edges and at most s vertices. In 1973, Brown, Erdős, and Sós conjectured that the limit \begin{equation*} \lim _{n\to \infty } n^{-2} f^{(3)}(n;k+2,k) \end{equation*} exists for all k and confirmed it for k=2. Recently, Glock showed this for k=3. We settle the next open case, k=4, by showing that f^{(3)}(n;6,4)=\left (\frac {7}{36}+o(1)\right)n^2 as n\to \infty. More generally, for all k\in \{3,4\}, r\ge 3 and t\in [2,r-1], we compute the value of the limit \lim _{n\to \infty } n^{-t}f^{(r)}(n;k(r-t)+t,k), which settles a problem of Shangguan and Tamo. [ABSTRACT FROM AUTHOR]

The article titled "Multi-Modal Modular Textile Sensor for Physical Human-Robot Interaction Using Band-Stop Filters" introduces a modular textile sensor system that can recognize human touch and measure contact force simultaneously. The sensor array consists of multiple sensor modules and only requires two wires to read all sensor outputs, thanks to band-stop filter circuits and frequency domain analysis. This sensor system can be easily attached to a robot's surface, improving its functionality and safety. The authors of the article are Jaehoon Kim, Junhyung Kim, and Yong-Lae Park. [Extracted from the article]

[Display omitted] • A new photodynamic therapy agent was disclosed. • Polymerization based on single benzene improved intersystem crossing efficiency. • The polymeric amino-single-benzene nano-aggregates showed significant therapeutic effects in the GBM-xenografted mouse model. Photodynamic therapy (PDT) has been highlighted as a promising strategy for tumor treatment, using in situ reactive oxygen species (ROS) generation which is achieved by irradiating a photosensitizer (PS) with a specific wavelength of light. The efficiency of PDT treatment is enhanced by the high intersystem crossing (ISC) process of PS, which promotes the generation of ROS. Herein, we disclosed a next-generation PS based on polymeric amino-single-benzene nano-aggregates (PANA) that show superior PDT efficacy by improving the ISC process. PANA demonstrates numerous advantageous features for practical applications, such as facile one-pot synthesis, high scalability (>10 g), a bright red emission, high physicochemical stability, high biosafety, and high PDT efficacy. In our study, PANA was applied for the glioblastoma (GBM) treatment using PDT, and it showed exceptional GBM homing properties and high therapeutic efficacy in the mouse animal model without any biological toxicity issues. [ABSTRACT FROM AUTHOR]

The electrochemical CO 2 reduction reaction (CO 2 RR) is a promising pathway for converting CO 2 into valuable products such as carbon monoxide (CO). Here we show that a remarkably high CO selectivity can be achieved in a gas diffusion electrode-based CO 2 RR flow cell by using different characteristics of the proton and CO 2 reduction reactions over a wide range of pHs, while H 2 evolution from H 2 O reduction can be effectively avoided. The potential window of a high-performance Ni single-atom catalyst for CO 2 RR does not overlap with that for H 2 O reduction; this allows CO selectivity to exceed 90% in a pH 2 electrolyte, thereby attaining a CO 2 -to-CO conversion rate of approximately 77%. Effects of electrolyte compositions on CO 2 RR are also evaluated. Techno-economic and life cycle assessments establish that CO 2 RR is more favorable in acidic conditions, which can minimize the additional CO 2 recycling and electrolyte regeneration processes, if surplus or cheap renewable electricity is available. [Display omitted] • Flow cell can warrant inherent CO production from CO 2 RR even in acid electrolytes. • To avoid H 2 O reduction is crucial to attain high CO selectivity during acidic CO 2 RR. • Using high-performance catalyst is an effective way for selective CO 2 -to-CO in acids. • Anions identity as well as alkali cations can also influence the CO selectivity. • TEA and LCA reveal acidic CO 2 RR would be favorable if cheap electricity is available. [ABSTRACT FROM AUTHOR]

Abstract Graphene-oxide (GO) quenching-based molecular beacon was developed for rapid and sensitive detection of RNAs in living cells and tissues. Here, we applied GO quenching-based molecular beacon sensor to visualize neurogenic miR-193a levels delivered via exosomes during cell-non-autonomous neurogenesis in neural progenitor cells on a microfluidic platform. Exosomal transport was visualized using CD63-RFP plasmid vector, and FAM-labeled peptide nucleic acid (PNA) probe for the miR-193 sequence was designed to detect endogenous miR-193 expression. Fluorescence signals of FAM-PNA193a-GO were recovered in dibutyryl-cAMP-induced F11 cells, resulting from increased expression of miR-193a after neuronal differentiation. We observed delivery of miR-193a-containing exosomes released from differentiated donor F11 cells to recipient undifferentiated F11 cells. Fluorescence recovery was evident in exosome-stimulated recipient individual F11 cells in the microfluidic system. We propose molecular beacon imaging using PNA-GO complex for visualization of individual cellular expression of mature microRNAs. This system reveals the precise spatial localization and temporal sequences of mature miRNAs by intercellular exosomal delivery of messages for processes such as cell-non-autonomous neurogenesis. Highlights • PNA-GO probe has high selectivity for target miR-193a. • It provides more sensitive imaging compared to other reported methods. • PNA-GO probe has also little or no cytotoxicity. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 33-year-old man presented to urology with a two-month history of abdominal and perineal pain, constipation, and voiding dysfunction. Topics include sarcomas have mesenchymal malignancies that represent 1% of adult cancers; and the initial presentation of pelvic masses tends to occur at an advanced stage with lower urinary tract symptoms.

A simple sensing methodology for rapid detection of multiple biomolecules in human health diagnostics remains a significant challenge. Herein, we developed a novel dispersant-free supra single-walled carbon nanotube (supra SWCNT)-coated glassy carbon electrode (GCE) for simultaneous sensing of biomolecules, such as ascorbic acid (AA), dopamine (DA), and uric acid (UA), in ex vivo mouse tissues. Supra SWCNTs with stable hydrogen bonds were synthesized via a simple chemical modification, after which they were characterized and confirmed using different physicochemical and electrochemical techniques. The supra SWCNT-coated GCE exhibited simultaneous sensing of AA, DA, and UA at linear dynamic ranges with lower detection limits of 12, 0.02, and 0.36 μM, respectively. Furthermore, they demonstrated high selectivity (with co-existing interference) and excellent reproducibility for effective sensing of the target biomolecules in different real samples. The rapid functioning, low cost, scalable preparation, and enhanced applicability for simultaneous sensing of target biomolecules in Parkinson's disease-induced mouse liver, kidney, and brain tissues suggest the suitability of the developed sensor for real-world applications. [Display omitted] • Dispersant-free supra SWCNT was prepared to facilitate step chemical modifications. • Supra SWCNTs freely dispersed in water without the addition of dispersing agents. • Supra SWCNTs/GCE were tested for highly sensitive simultaneous biomolecule sensing. • Real-time biomolecule sensing in PD mouse models achieved satisfying results. [ABSTRACT FROM AUTHOR]

A celebrated theorem of Pippenger, and Frankl and Rödl states that every almost‐regular, uniform hypergraph H$\mathcal {H}$ with small maximum codegree has an almost‐perfect matching. We extend this result by obtaining a conflict‐free matching, where conflicts are encoded via a collection C$\mathcal {C}$ of subsets C⊆E(H)$C\subseteq E(\mathcal {H})$. We say that a matching M⊆E(H)$\mathcal {M}\subseteq E(\mathcal {H})$ is conflict‐free if M$\mathcal {M}$ does not contain an element of C$\mathcal {C}$ as a subset. Under natural assumptions on C$\mathcal {C}$, we prove that H$\mathcal {H}$ has a conflict‐free, almost‐perfect matching. This has many applications, one of which yields new asymptotic results for so‐called 'high‐girth' Steiner systems. Our main tool is a random greedy algorithm which we call the 'conflict‐free matching process'. [ABSTRACT FROM AUTHOR]

Herein, we present a new strategy for inhibiting the volume expansion of MoO 2 during lithiation and delithiation by preparing MoO 2 /Mo 2 C core-shell particles deposited on reduced graphene oxide (RGO). The MoO 2 /Mo 2 C/RGO composite was synthesized by first preparing the MoO 2 /RGO composite in supercritical methanol (scMeOH) followed by carbothermal hydrogen reduction. Carbon migration from RGO and organic moieties attached to the surface of MoO 2 particles synthesized in scMeOH produced a Mo 2 C film during carbothermal reduction. When tested as an anode in lithium ion batteries, the MoO 2 /Mo 2 C/RGO composite exhibited an increased initial coulombic efficiency (77%), long-term cyclability (500 mAh g −1 at 50 mA g −1 after 150 cycles), and high-rate performance (200 mAh g −1 at 1 A g −1 ) compared with those of the MoO 2 /RGO composite (53%; 280 mAh g −1 at 50 mA g −1 after 150 cycles; 120 mAh g −1 at 1 A g −1 ). Electrochemical impedance spectra showed that the MoO 2 /Mo 2 C/RGO composite exhibited reduced solid electrolyte interphase (SEI) resistance and facilitated Li ion transport into the electrode. The presence of Mo 2 C with low electrochemical activity, but high electronic conductivity, could decrease SEI formation and suppress volume expansion, which prolonged the cycling life. [ABSTRACT FROM AUTHOR]

Background: Humans alter gait in response to unusual gait circumstances to accomplish the task of walking. For instance, subjects spontaneously increase leg compliance at a step length threshold as step length increases. Here we test the hypothesis that this transition occurs based on the level of energy expenditure, where compliant walking becomes less energetically demanding at long step lengths.Research Question: To map and compare the metabolic cost of normal and compliant walking as step length increases.Methods: 10 healthy individuals walked on a treadmill using progressively increasing step lengths (100%, 120%, 140% and 160% of preferred step length), in both normal and compliant leg walking as energy expenditure was recorded via indirect calorimetry. Leg compliance was controlled by lowering the center-of-mass trajectory during stance, forcing the leg to flex and extend as the body moved over the foot contact.Results: For normal step lengths, compliant leg walking was more costly than normal walking gait, but compliant leg walking energetic cost did not increase as rapidly for longer step lengths. This led to an intersection between normal and compliant walking cost curves at 114% relative step length (regression analysis; r2 = 0.92 for normal walking; r2 = 0.65 for compliant walking).Significance: Compliant leg walking is less energetically demanding at longer step lengths where a spontaneous shift to compliant walking has been observed, suggesting the human motor control system is sensitive to energetic requirements and will employ alternate movement patterns if advantageous strategies are available. The transition could be attributed to the interplay between (i) leg work controlling body travel during single stance and (ii) leg work to control energy loss in the step-to-step transition. Compliant leg walking requires more stance leg work at normal step lengths, but involves less energy loss at the step-to-step transition for very long steps. [ABSTRACT FROM AUTHOR]

We determine, for all k ≥ 6 , the typical structure of graphs that do not contain an induced 2 k -cycle. This verifies a conjecture of Balogh and Butterfield. Surprisingly, the typical structure of such graphs is richer than that encountered in related results. The approach we take also yields an approximate result on the typical structure of graphs without an induced 8-cycle or without an induced 10-cycle. [ABSTRACT FROM AUTHOR]

Sodium ion batteries (NIBs) have gained considerable attention for large-scale energy storage applications because of the lower cost and higher abundance of Na than Li. In this study, we demonstrate that silicon oxycarbides (SiOCs), in which free carbon phases are imbedded in amorphous glassy SiO x C y phases, can be promising candidates as anodes for NIBs. The SiOC samples were synthesized by the pyrolysis of low-cost silicone oil in a H 2 /Ar flow condition. When tested as an anode in NIBs, the SiOC sample calcined at 900 °C exhibited an excellent reversible capacity of 160 mAh g −1 at 25 mA g −1 after 200 cycles and a high rate performance of 62 mAh g −1 at 800 mA g −1 . More importantly, the SiOC electrode exhibited an excellent long-term cycling performance of 0.09 mAh g −1 decay per cycle for 650 cycles. The electrochemical properties of SiOC in an NIB were compared with those in an LIB to gain an insight into its ion storage mechanism. The effects of calcination temperature, calcination time, and ball milling time on the physicochemical and electrochemical properties of the SiOC electrode are discussed. [ABSTRACT FROM AUTHOR]

The r-dynamic choosability of a graph G, written [ABSTRACT FROM AUTHOR]

A strong k - edge-coloring of a graph G is a mapping from E ( G ) to { 1 , 2 , … , k } such that every two adjacent edges or two edges adjacent to the same edge receive distinct colors. The strong chromatic index χ s ′ ( G ) of a graph G is the smallest integer k such that G admits a strong k -edge-coloring. We give bounds on χ s ′ ( G ) in terms of the maximum degree Δ ( G ) of a graph G when G is sparse, namely, when G is 2 -degenerate or when the maximum average degree Mad ( G ) is small. We prove that the strong chromatic index of each 2 -degenerate graph G is at most 5 Δ ( G ) + 1 . Furthermore, we show that for a graph G , if Mad ( G ) < 8 ∕ 3 and Δ ( G ) ≥ 9 , then χ s ′ ( G ) ≤ 3 Δ ( G ) − 3 (the bound 3 Δ ( G ) − 3 is sharp) and if Mad ( G ) < 3 and Δ ( G ) ≥ 7 , then χ s ′ ( G ) ≤ 3 Δ ( G ) (the restriction Mad ( G ) < 3 is sharp). [ABSTRACT FROM AUTHOR]

Let k ≥ 3 be an odd integer and let n be a sufficiently large integer. We prove that the maximum number of edges in an n -vertex k -uniform hypergraph containing no 2-regular subgraphs is ( n − 1 k − 1 ) + ⌊ n − 1 k ⌋ , and the equality holds if and only if H is a full k -star with center v together with a maximal matching omitting v . This verifies a conjecture of Mubayi and Verstraëte. [ABSTRACT FROM AUTHOR]