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The dynamics of polymer nanocomposites varies depending on the physics and chemistry at the polymer–nanoparticle interface. The physical aging of the nanocomposites is accelerated or retarded based on interfacial interactions and the state of polymer adsorption at the interfaces. In this study, we investigated the aging kinetics of silica–polystyrene nanocomposites using differential scanning calorimetry, focusing on the effect of local conformations of chains adsorbed on the nanofiller surface. The results show that the temperature dependence of the aging rate follows a Vogel–Fulcher–Tammann relationship at high temperatures, whereas it exhibits an Arrhenius-like behavior below a characteristic temperature (Tc). Notably, at T < Tc, the aging rate decreases with increasing loop height of the chains adsorbed on the filler surface, but the activation energy remains unchanged. We proposed that the suppression of the aging rate at T < Tc is likely related to an increase in the length scale over which the slow interfacial dynamics can propagate due to the increased topological interactions between the chain loops of a larger size and the free chains in the matrix. The increased packing frustration occurring at the filler surface occupied by the larger loops might also contribute to the decreased aging rate. [ABSTRACT FROM AUTHOR]

Thermoelectric coolers (TECs) offer a promising solution for direct cooling of local hotspots and active thermal management in advanced electronic systems. However, TECs present significant trade-offs among spatial cooling, heating, and power consumption. The optimization of TECs requires extensive simulations, which are impractical for managing actual systems with multiple hotspots under spatial and temporal variations. In this study, we present a novel machine learning-assisted optimization algorithm for thermoelectric coolers that can achieve global optimal temperature by individually controlling TEC units based on real-time multi-hotspot conditions across the entire domain. We train a convolutional neural network with a combination of the inception module and multi-task learning approach to comprehend the coupled thermal-electrical physics underlying the system and attain accurate predictions for both temperature and power consumption with and without TECs. Due to the intricate interaction among passive thermal gradient, Peltier effect and Joule effect, a local optimal TEC control experiences spatial temperature trade-off which may not lead to a global optimal solution. To address this issue, we develop a backtracking-based optimization algorithm using the machine learning model to iterate all possible TEC assignments for attaining global optimal solutions. For any m × n matrix with NHS hotspots (n, m ≤ 10, 1 ≤ NHS ≤ 20), our algorithm is capable of providing 52.4% peak temperature reduction and its corresponding TEC array control within an average of 1.64 s while iterating through tens of temperature predictions behind-the-scenes. This represents a speed increase of over three orders of magnitude compared to traditional finite element method strategies which take approximately 27 min. [ABSTRACT FROM AUTHOR]

In this paper, we present a combined experimental and theoretical study that explored the initial sticking of water on cooled surfaces. Specifically, these ultra-high vacuum gas–surface scattering experiments utilized supersonic molecular beam techniques in conjunction with a cryogenically cooled highly oriented pyrolytic graphite crystal, giving control over incident kinematic conditions. The D2O translational energy spanning 300–750 meV, the relative D2O flux, and the incident angle could all be varied independently. Three different experimental measurements were made. One involved measuring the total amount of D2O scattering as a function of surface temperature to determine the onset of sticking under non-equilibrium gas–surface collision conditions. Another measurement used He specular scattering to assess structural and coverage information for the interface during D2O adsorption. Finally, we used time-of-flight (TOF) measurements of the scattered D2O to determine how energy is exchanged with the graphite surface at surface temperatures above and near the conditions needed for gaseous condensation. For comparison and elaboration of the roles that internal degrees of freedom play in this process, we also did similar TOF measurements using another mass 20 incident particle, atomic neon. Enriching this study are precise molecular dynamics simulations that elaborate on gas–surface energy transfer and the roles of molecular degrees of freedom in gas–surface collisional energy exchange processes. This study furthers our fundamental understanding of energy exchange and the onset of sticking and ultimately gaseous condensation for gas–surface encounters occurring under high-velocity flows. [ABSTRACT FROM AUTHOR]

Thermal transport plays a pivotal role across diverse disciplines, yet the intricate relationship between amorphous network structures and thermal conductance properties remains elusive due to the absence of a reliable and comprehensive network's dataset to be investigated. In this study, we have created a dataset comprising multiple amorphous network structures of varying sizes, generated through a combination of the node disturbance method and Delaunay triangulation, to fine-tune an initially random network toward both increased and decreased thermal conductance C. The tuning process is guided by the simulated annealing algorithm. Our findings unveil that C is inversely dependent on the normalized average shortest distance L n o r m connecting heat source nodes and sink nodes, which is determined by the network topological structure. Intuitively, the amorphous network with increased C is associated with an increased number of bonds oriented along the thermal transport direction, which shortens the heat transfer distance from the source to sink node. Conversely, thermal transport encounters impedance with an augmented number of bonds oriented perpendicular to the thermal transport direction, which is demonstrated by the increased L n o r m . This relationship can be described by a power law C = L n o r m α , applicable to the diverse-sized amorphous networks we have investigated. [ABSTRACT FROM AUTHOR]

Chemical pressure is widely applied to antiferroelectrics (AFEs) as a criterion to enhance their antiferroelectricity. However, NaNbO3 (NN)-based ceramic with well-defined double polarization hysteresis (P–E) loops was rarely reported based on this strategy, and the effect of chemical pressure on antiferroelectricity remains to be understood. In this work, the Me cations (Me is Ti, Sn, Zr) with different ionic radii were introduced into the component system 0.76NaNbO3–0.20AgNbO3–0.04CaMeO3 to tune the negative chemical pressure and investigate its effect on antiferroelectricity. The enhancement of negative chemical pressure can effectively stabilize the AFE phase and reduce hysteresis, as revealed by the P–E loops and dielectric properties, which is further confirmed by the change in crystal lattice parameters and in situ Raman spectra. Rietveld refinement of x-ray powder diffraction reveals that the enhanced negative chemical pressure mainly reduces the cation off-centering displacement and [BO6] octahedral tilting angles. As a result, the 0.76NaNbO3–0.20AgNbO3–0.04CaZrO3 exhibits good reversibility of the electric field-induced antiferroelectric–ferroelectric phase transition and well-defined double P–E loops. This work reveals the underlying mechanism of chemical pressure and provides an effective way of discovering new NN-based AFEs. [ABSTRACT FROM AUTHOR]

Micrometer-sized magnetic particles have been widely used in magnetic force microscopy, magnetic resonance force microscopy, and bio-sensing. To quantitatively interpret the data obtained with magnetic particles, it is important to know the magnetic properties of the particles. However, the magnetic moment of individual particle is usually too small to be measured by common instruments for samples with large volume. Here, we present a method to characterize magnetic microspheres using patterned FePt thin films as standard samples. The FePt thin film in the L 1 0 phase has perpendicular magnetic anisotropy, and the patterned features can be magnetized to near single-domain magnets, which make them suitable standards for magnetic sphere calibration with magnetic force microscopy. Multiple linear regression is used to analyze the frequency shift images and obtain the effective dipole moment of the spheres. The position of the dipole moment is obtained by minimizing the residuals in multiple linear regression with a gradient descent algorithm. Three NdFeB spheres of different diameters were measured. It was found that the magnetization increases with the increase in the diameter of the sphere, possibly due to the weakening of ferromagnetism on the surface. [ABSTRACT FROM AUTHOR]

A large open-circuit voltage (VOC) deficit is the major challenge hindering the efficiency improvement of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. Cation substitution, or doping, is usually an effective strategy to achieve carrier regulation and improve efficiency. In this work, we developed a rare-earth element lanthanum (La) doped CZTSSe thin-film solar cell by directly introducing La3+ ions into the CZTS precursor solution. Such a proposed La doping approach could effectively enhance light harvesting, adjust the bandgap, and increase the electron diffusion length. Furthermore, appropriate concentrations of La doping can reduce harmful defect cluster. Benefiting from the La doping, the VOC significantly increases from 431 to 497 mV. Consequently, the power conversion efficiency is enhanced significantly from 6.54% (VOC = 431 mV, JSC = 25.50 mA/cm2, FF = 58.28%) for the reference cell to 10.21% (VOC = 497 mV, JSC = 35.20 mA/cm2, FF = 58.41%) for the optimized La-doped cell. This research provides a new direction for enhancing the performance of CZTSSe cells, offering promising prospects for the future of CZTSSe thin-film solar cells. [ABSTRACT FROM AUTHOR]

Grain boundary (GB) segregation models are derived for multi-principal element alloys (MPEAs) and high-entropy alloys (HEAs). Differing from classical models where one component is taken as a solvent and others are considered solutes, these models are referenced to the bulk composition to enable improved treatments of MPEAs and HEAs with no principal components. An ideal solution model is first formulated and solved to obtain analytical expressions that predict GB segregation and GB energy in MPEAs and HEAs. A regular solution model is further derived. The GB composition calculated using the simple analytical expression derived in this study and data from the Materials Project agrees well with a prior atomistic simulation for NbMoTaW. The simplicity of the derived analytical expressions makes them useful for not only conveniently predicting GB segregation trends in HEAs but also analyzing nascent interfacial phenomena in compositionally complex GBs. As an application example, the models are used to further derive a set of equations to elucidate an emergent concept of high-entropy grain boundaries. [ABSTRACT FROM AUTHOR]

Identifying the oxidation structure of two-dimensional interfaces is crucial to improve surface chemistry and electronic properties. Beyond graphene with only phenyl rings, a novel carbon-nitrogen material, C3N, presents an intrinsic heterogeneous surface morphology where each phenyl ring is encircled by six nitrogen atoms, yet its atomistic oxidation structure remains unclear. Here, combining a series of density functional theory calculations and ab initio molecular dynamics simulations, we demonstrate that thermodynamically favorable oxidation loci are confined to the phenyl ring, and kinetic transformations of oxidation structures are feasible along the phenyl ring, whereas those toward nitrogen atoms are proven to be extremely difficult. These results are attributed to the lower barrier of oxygen atom migration along the phenyl ring, while the significantly high barriers toward nitrogen atoms are due to the heterogeneous potential energy surface for oxygen–C3N interaction. This work highlights the significance of surface morphology on the characteristics of oxidation structure, offering insights into tunable electronic properties via confined interfacial oxidation. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) is a crucial technique to prepare high-quality graphene because of its controllability. In the research, we perform a systematic computational fluid dynamics numerical investigation on the effect of gas-phase reaction dynamics on the graphene growth in a horizontal tube CVD reactor. The research results indicate that the gas-phase chemical reactions in the CVD reactor are in a nonequilibrium state, as evidenced by the comparison of species mole fraction distributions during the CVD process and under chemical equilibrium conditions. The effect of gas-phase reaction dynamics on the deposition rate of graphene under different conditions is studied, and our research shows that the main causes of change in graphene growth rates under different conditions are gas-phase reaction dynamics and active species transport. The results of numerical simulation agree well with the experimental phenomena. The research results also indicate that, for methane, the main limiting factor of graphene growth is the surface kinetic reaction rate. Conversely, for active species, the main limiting factor of graphene growth is species transport. Our research suggests that the growth rate of graphene can be regulated from the perspective of the gas reaction mechanism. This method has theoretical guiding significance and can be extended to the preparation of large-area graphene. [ABSTRACT FROM AUTHOR]

Er3+/Yb3+ co-doped Na2O–CaF2–ZnO–Al2O3–SiO2 glasses with different Zn/Si ratios were prepared using the melt-quenching technique. The thermal stability was investigated by differential scanning calorimetry. Additionally, the absorption spectra were also analyzed to gather more information about their properties. The down-conversion luminescence corresponding to the strongest fluorescence at a wavelength of 547 nm was obtained under the 378 nm excitation, and a 4S3/2 level fluorescence lifetime was studied. By utilizing a laser pump with a wavelength of 980 nm, the process of both up-conversion and down-conversion luminescence was accomplished. In particular, the glasses substantially enhance fluorescence properties when the Zn/Si ratio is about 0.16. The changes in the Zn/Si ratio lead to modifications in the glass network structure, changing the coordination field environment around the fluorescence center and ultimately impacting the luminescence properties of the rare-earth ions. These effects are evidenced through the findings obtained from Fourier transform infrared spectroscopy and fluorescence spectroscopy analysis of the glass material. [ABSTRACT FROM AUTHOR]

Electron spin relaxation is, on many occasions, considered an elephant in the room that challenges the idea of a radical-pair compass, a leading hypothesis for the navigation of migratory avian species. It has been widely recognized that an effective radical-pair magnetoreceptor requires a relaxation time that is long enough for an external magnetic field as weak as the geomagnetic field to significantly modify the coherent spin dynamics. However, previous studies proposed that certain spin relaxation, far quicker than the radical recombination reactions, could enhance, rather than degrade, the directional sensitivity of a radical-pair magnetoreceptor. Here, I investigate relaxation effects on the singlet–triplet interconversion of a model radical pair and find that the enhancement effect originates from population relaxation over a period of several microseconds as a result of efficient spin decoherence. Insights into the truncated spin systems shed light on the physics behind them. I further investigate the possibilities of such enhancement in cryptochrome-based magnetoreception, in which electron hopping takes place between tryptophan residues. [ABSTRACT FROM AUTHOR]

This paper proposes a piezoelectric energy harvester that concentrates force on the piezoelectric element by parallel springs. When vibrating, the force exerted by the mass is released at three equal points on the surface of the brass substrate through three parallel springs. This concentrated release of energy through the spring amplification effect facilitates large deformation of the piezoelectric ceramic sheet, resulting in a higher charge output. The results show that under the combined action of a 14 g annular hollow mass and a 0.3 mm wire diameter stainless steel spring, the energy harvester based on the lead zirconate titanate ceramic exhibited an outstanding output power of 1.0–32.1 mW at a low resonance frequency with acceleration amplitudes of 0.5–3 g (1 g = 9.8 m/s2). More importantly, to match the vibration frequency of the actual environment, this paper optimized the structure of the harvester and proposed that the harvester can be designed by selecting the weight of the mass block, the parameters and number of springs, and the shape of the brass substrate. The energy harvester designed in this study is expected to capture energy from low-frequency natural environments and exhibit outstanding output performance, which can provide guidelines for future efforts in this direction. [ABSTRACT FROM AUTHOR]

Doubly resonant sum frequency generation (DR-SFG) serves as a potent characteristic technique for probing the electronic spectra and vibronic coupling of molecules on surfaces. In this study, we successfully developed a novel infrared (IR)–white light (WL) DR-SFG spectroscopy based on narrowband IR and tunable broadband WL. This novel method was employed to explore the excitation spectrum and vibronic couplings of sub-monolayer Rhodamine 6G molecules. Our findings elucidate that the xanthene skeleton vibrational modes exhibit strong coupling with the S0–S1 electronic transition. Notably, we observed not only the 0–0 transition of the S0–S1 electronic continuum but also the 0–1 transition, a first time observation in the realm of DR-SFG spectroscopy. This advanced DR-SFG spectroscopy methodology facilitates a more sensitive examination of electronic spectra and the coupling between electronic transitions and vibrational modes, heralding a significant advancement in the understanding of molecular interactions on surfaces. [ABSTRACT FROM AUTHOR]

Current–voltage characteristics and low-frequency (LF) noise of industrial-quality AlGaAs/InGaAs/GaAs pseudomorphic high-electron-mobility transistors are evaluated as a function of bias stress and temperature. A small positive shift of threshold voltage Vth and negligible degradation in peak transconductance GM are observed under ON-state bias conditions at elevated temperatures. The Vth measurements suggest activation of an acceptor-like defect or impurity center. The GM measurements demonstrate that newly activated defects are not located close enough to the two-dimensional electron gas to scatter carriers strongly. First-principles calculations and comparisons with previous work suggest that OAs impurity centers, other oxygen-related defects, isolated AsGa antisites, and dopant-based DX centers may contribute significantly to low-frequency (LF) noise in as-processed devices. LF noise is relatively unaffected by voltage stress at elevated temperatures, consistent with the small changes in Vth and peak GM. [ABSTRACT FROM AUTHOR]

Thermal issue has been regarded as one of the bottlenecks for GaN high-electron-mobility transistor (HEMT) performance and reliability, which highlights the importance of accurate thermal modeling. In the present work, we propose a GP (Gaussian process)-resistor–capacitor compact thermal model integrated with the ensemble Kalman filter (EnKF) to handle the nonlinear problems attributed to the temperature-dependent properties of GaN HEMTs under large-signal working conditions. The GP predictor is employed for the nonlinear correction term, with strong ability and extendibility to characterize various temperature-dependent relations resulting from different design configurations and materials. The model is identified via the EnKFs by inputting a sequence of channel temperature oscillations induced by imposing a large-signal continuous wave heating source to the device. Furthermore, an adaptation mode is devised for the in situ and timely update of the model parameters to adapt to the thermal variability of GaN devices, avoiding storing a large amount of historical data and repeated offline regressions. The validation of our modeling scheme is conducted through the case study on GaN-on-SiC HEMT's detailed 3D finite element method simulations. [ABSTRACT FROM AUTHOR]

Coarse-graining of fluids is challenging because fluid particles are unbound and diffuse long distances in time. One approach creates coarse-grain variables that group all particles within a region centered on specific points in space and accounts for the movement of particles among such regions. In our previous work, we showed that in many cases, potential interactions for such a scheme adopted a generalized quadratic form, whose parameters depend on means, variances, and correlation coefficients among the coarse-grain variables. In this work, we use statistical mechanics to derive analytic expressions for these parameters, using properties of the fluid, including pair distribution functions. These expressions are compared against simulation-derived values and shown to be in good agreement. This approach can be used to calculate a priori the potential for any homogeneous, simple fluid, without the need for fitting procedures or matching, thus increasing the ease of use of this coarse-grain scheme and creating a foundation for large-scale bottom-up simulations. Furthermore, these expressions provide a quantitative way of studying the boundary between discrete (atomic) and continuum models of fluids. [ABSTRACT FROM AUTHOR]

Photonic spin–orbit (SO) coupling is an important physical mechanism leading to numerous interesting phenomena in the systems of microcavity photons and exciton-polaritons. We report the effect of SO coupling in a tunable open-access microcavity embedded with anisotropic active media. The SO coupling associated with the TE–TM splitting results in an emergent anisotropy, which further leads to fine energy splittings allowing clear observation of the full set of eigenstates, in sharp contrast with the isotropic situation which leads to the isotropic eigenstates of spin vortices. We show that the photonic potential can be engineered by playing with the relation between the emergent anisotropy and the cavity ellipticity. All the experimental results are well reproduced by the degenerate perturbation theory. Our results constitute a significant extension to the research field of microcavity spinoptronics, with potential applications in polarization control and optical property measurement of photonic devices and materials. [ABSTRACT FROM AUTHOR]

In previous methods for solving the equivalent resistance of large‐scale complex resistive networks, abstract Green's functions or complex matrix transformations were often involved, which brought more difficulties to the readers' understanding. For this reason, this study proposed an innovative method based entirely on simple algebraic operations. This method combined the equivalent decomposition method with the improved recursion‐transform (IRT) method. It was divided into three steps: Firstly, by introducing the concept of “negative resistance,” one of the resistors of the network to be solved was equivalently decomposed into the parallel connection of three resistors, so that the whole resistive network was equivalently decomposed into three parts, namely, a left network, a middle network, and a right network. Then, the equivalent resistances of the left network and the right network were calculated using the IRT method, respectively. Finally, the equivalent resistance between any nodes was solved according to the parallel relationship of the equivalent resistances of the left network, the middle network, and the right network. The equivalent resistance between any nodes in the 2 × 4 × n tower‐shaped cascaded resistive network was successfully solved using this method. The calculation showed that because the concept of negative resistance was introduced in this method, the equivalent resistance problem of any nodes in the network was changed into the equivalent resistance problem of the initial nodes of the network, which made the equivalent resistance problem of any nodes simple, convenient, fast and easy to understand. [ABSTRACT FROM AUTHOR]

Deuteration has emerged as a significant method for investigating kinetic isotope effects in chemical reactions. In recent years, research on deuteration has revealed that this reaction often alters the pharmacokinetic or toxicological properties of drug molecules, thereby enhancing their therapeutic effect. Therefore, deuteration is considered as a potential avenue for drug research direction. Since the approval of the first deuterated drug, “deutetrabenazine,” by the American Food and Drug Administration (FDA) in 2017, deuteration has been applied in the development of a variety of novel drugs. Research on deuteration technology has matured with the publication of numerous deuteration strategies. This article reviews recently reported strategies for late‐stage selective deuteration, discusses the challenges associated with current deuteration strategies, and presents future prospects for the synthesis of deuterated drugs. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is an essential element for plant growth, and its deficiency can cause decreased crop yield. This study systematically evaluated the low-phosphate (Pi) response traits in a large population at maturity and seedling stages, and explored candidate genes and their interrelationships with specific traits. The results revealed a greater sensitivity of seedling maize to low-Pi stress compared to that at maturity stage. The phenotypic response patterns to low-Pi stress at different stages were independent. Chlorophyll content was found to be a potential indicator for screening low-Pi-tolerant materials in the field. A total of 2900 and 1446 significantly associated genes at the maturity and seedling stages were identified, respectively. Among these genes, 972 were uniquely associated with maturity traits, while 330 were specifically detected at the seedling stage under low-Pi stress. Moreover, 768 and 733 genes were specifically associated with index values (low-Pi trait/normal-Pi trait) at maturity and seedling stage, respectively. Genetic network diagrams showed that the low-Pi response gene Zm00001d022226 was specifically associated with multiple primary P-related traits under low-Pi conditions. A total of 963 out of 2966 genes specifically associated with traits under low-Pi conditions or index values were found to be induced by low-Pi stress. Notably, ZmSPX4.1 and ZmSPX2 were sharply up-regulated in response to low-Pi stress across different lines or tissues. These findings advance our understanding of maize’s response to low-Pi stress at different developmental stages, shedding light on the genes and pathways implicated in this response. [ABSTRACT FROM AUTHOR]

Background: There is a lack of data on the epidemiology of IBS in pregnant and postpartum patients in the United States. Methods: A retrospective claims analysis was conducted in a cohort of 1,618,379 patients with ≥1 delivery hospitalization between 2013–2019 utilizing ICD‐9 and ICD‐10 codes after merging inpatient and outpatient claims. Obstetric, psychological, and other medical comorbidities were also examined. Key Results: The prevalence of IBS in our cohort was 1.38%. Pregnant and postpartum patients with IBS were more likely to have psychological comorbidities including depression (OR 2.93, CI 2.83–3.03), postpartum depression (OR 3.00, CI 2.91–3.09), and anxiety (OR 3.74, CI 3.64–3.84). They were also more likely to have migraines (OR 3.04, CI 2.94–3.15) and connective tissue disease or autoimmune disease (OR 3.54, CI 3.22–3.89). Conclusion: The prevalence of IBS in pregnant and postpartum patients in a large claims database was 1.38%. Pregnant and postpartum patients with IBS have a higher odd of psychological comorbidities in addition to medical comorbidities such as migraines, connective tissue, and autoimmune disease. Future studies should focus on validating and characterizing the impact and directionality of co‐existing comorbidities on IBS severity and the development of new‐onset IBS during pregnancy and the postpartum period. [ABSTRACT FROM AUTHOR]

Examining the connection between P and starch-related signals can help elucidate the balance between nutrients and yield. This study utilized 307 diverse maize inbred lines to conduct multi-year and multi-plot trials, aiming to explore the relationship among P content, starch content, and 100-kernel weight (HKW) of mature grains. A significant negative correlation was found between P content and both starch content and HKW, while starch content showed a positive correlation with HKW. The starch granules in grains with high-P and low-starch content (HPLS) were significantly smaller compared to grains with low-P high-starch content (LPHS). Additionally, mian04185-4 (HPLS) exhibited irregular and loosely packed starch granules. A significant decrease in ZmPHOs genes expression was detected in the HPLS line ZNC442 as compared to the LPHS line SCML0849, while no expression difference was observed in AGPase encoding genes between these two lines. The down-regulated genes in ZNC442 grains were enriched in nucleotide sugar and fatty acid anabolic pathways, while up-regulated genes were enriched in the ABC transporters pathway. An accelerated breakdown of fat as the P content increased was also observed. This implied that HPLS was resulted from elevated lipid decomposition and inadequate carbon sources. The GWAS analysis identified 514 significantly associated genes, out of which 248 were differentially expressed. Zm00001d052392 was found to be significantly associated with P content/HKW, exhibiting high expression in SCML0849 but almost no expression in ZNC442. Overall, these findings suggested new approaches for achieving a P-yield balance through the manipulation of lipid metabolic pathways in grains. [ABSTRACT FROM AUTHOR]

We synthesized a low metal-to-sulfur atomic ratio (0.5) FeCoS4, exhibiting high reversible specific capacity. Reduced graphene oxide was covered on the surface to improve the cycling stability and rate performance further. Density functional theory calculations show that composite materials can effectively increase the adsorption energy and enhance the diffusion kinetics. [ABSTRACT FROM AUTHOR]

Breathable membranes with micropores enable the transfer of gas molecules while blocking liquids and solids, and have a wide range of applications in medical, industrial, environmental, and energy fields. Breathability is highly influenced by the nature of a material, pore size, and pore structure. Preparation methods and the incorporation of functional materials are responsible for the variety of physical properties and applications of breathable membranes. In this review, the preparation methods of breathable membranes, including blown film extrusion, cast film extrusion, phase separation, and electrospinning, are discussed. According to the antibacterial, hydrophobic, thermal insulation, conductive, and adsorption properties, the application of breathable membranes in the fields of electronics, medicine, textiles, packaging, energy, and the environment are summarized. Perspectives on the development trends and challenges of breathable membranes are discussed. [ABSTRACT FROM AUTHOR]

To explore cost-effective and efficient phytoremediation strategies, this study investigated the distinct roles of earthworm activity and mucus in enhancing Cd phytoextraction from soils contaminated by Festuca arundinacea, focusing on the comparative advantages of selective leaf harvesting versus traditional whole-plant harvesting methods. Our study employed a horticultural trial to explore how earthworm activity and mucus affect Festuca arundinacea' s Cd phytoremediation in soils using control, earthworm, and mucus treatments to examine their respective effects on plant growth and Cd distribution. Earthworm activity increased the dry weight of leaves by 13.5% and significantly increased the dry weights of declining and senescent leaves, surpassing that of the control by more than 40%. Earthworm mucus had a similar, albeit less pronounced, effect on plant growth than earthworm activity. This study not only validated the significant role of earthworm activity in enhancing Cd phytoextraction by Festuca arundinacea, with earthworm activity leading to over 85% of Cd being allocated to senescent tissues that comprise only approximately 20% of the plant biomass, but also highlighted a sustainable and cost-effective approach to phytoremediation by emphasizing selective leaf harvesting supported by earthworm activity. By demonstrating that earthworm mucus alone can redistribute Cd with less efficiency compared to live earthworms, our findings offer practical insights into optimizing phytoremediation strategies and underscore the need for further research into the synergistic effects of biological agents in soil remediation processes. [ABSTRACT FROM AUTHOR]

In this paper, by using the residue method of complex analysis, we obtain a q-analogue for partial-fraction decomposition of the rational function x M (x + 1) n λ . As applications, we deduce the corresponding q-algebraic and q-combinatorial identities which are the q-extensions of Chu' results. [ABSTRACT FROM AUTHOR]

Chiral hybrid metal halides hold great potential as circularly polarized luminescence light sources. Herein, we have obtained two enantiomeric pairs of one‐dimensional hybrid chiral manganese(II) chloride single crystals, R/S‐(3‐methyl piperidine)MnCl3 (R/S‐1) and R/S‐(3‐hydroxy piperidine)MnCl3 (R/S‐2), crystallizing in the non‐centrosymmetric space group P212121. In comparison to R/S‐1, R/S‐2 single crystals not only show red emission with near‐unity photoluminescence quantum yield (PLQY) and high resistance to thermal quenching but also exhibit circularly polarized luminescence with an asymmetry factor (glum) of 2.5×10−3, which can be attributed to the enhanced crystal rigidity resulting from the hydrogen bonding networks between R/S‐(3‐hydroxy piperidine) cations and [MnCl6]4− chains. The circularly polarized luminescence activities originate from the asymmetric [MnCl6]4− luminophores induced by N−H⋅⋅⋅Cl hydrogen bonding with R/S‐(3‐hydroxy piperidine). Moreover, these samples demonstrate great application potential in circularly polarized light‐emitting diodes and X‐ray scintillators. This work shows a highly efficient photoluminescent Mn‐based halide and offers a strategy for designing multifunctional chiral metal halides. [ABSTRACT FROM AUTHOR]

Chiral hybrid metal halides hold great potential as circularly polarized luminescence light sources. Herein, we have obtained two enantiomeric pairs of one‐dimensional hybrid chiral manganese(II) chloride single crystals, R/S‐(3‐methyl piperidine)MnCl3 (R/S‐1) and R/S‐(3‐hydroxy piperidine)MnCl3 (R/S‐2), crystallizing in the non‐centrosymmetric space group P212121. In comparison to R/S‐1, R/S‐2 single crystals not only show red emission with near‐unity photoluminescence quantum yield (PLQY) and high resistance to thermal quenching but also exhibit circularly polarized luminescence with an asymmetry factor (glum) of 2.5×10−3, which can be attributed to the enhanced crystal rigidity resulting from the hydrogen bonding networks between R/S‐(3‐hydroxy piperidine) cations and [MnCl6]4− chains. The circularly polarized luminescence activities originate from the asymmetric [MnCl6]4− luminophores induced by N−H⋅⋅⋅Cl hydrogen bonding with R/S‐(3‐hydroxy piperidine). Moreover, these samples demonstrate great application potential in circularly polarized light‐emitting diodes and X‐ray scintillators. This work shows a highly efficient photoluminescent Mn‐based halide and offers a strategy for designing multifunctional chiral metal halides. [ABSTRACT FROM AUTHOR]

Immunogenic cell death (ICD) is a newly discovered form of cellular demise that triggers adaptive immune responses mediated by T cells. However, the immunogenic cell death-related lncRNAs (ICDRLs) involved in bladder cancer (BC) development and progression remain to be further elucidated. Molecular profiling data and clinicopathological information for BC patients were obtained from TCGA, and the ICDRGs list was obtained from published literature. For the identification of ICDRLs, Pearson co-expression analysis was performed, and a prognostic signature based on 13 ICDRLs was constructed by univariate assays and LASSO assays. Herein, an ICDRLSig consisting of 13 ICDRLs was constructed. KM curves and ROC curves demonstrated that the constructed signature in the TCGA training, testing, entire and external sets have good predictive performance. Multivariate assays illuminated that the signature is an independent predictor for BC patients' OS, exhibiting greater predictive power for the survival than traditional clinicopathological features. Additionally, patients in the high-ICDRLSig risk subgroup had more abundant immune infiltration, higher immune checkpoint gene expression, lower TMB and poorer response to immunotherapy. We have developed a novel ICDRLSig that can be exploited for survival prediction and provide a reference for further individualized treatment. [ABSTRACT FROM AUTHOR]

Syngas conversion serves as a gas‐to‐liquid technology to produce liquid fuels and valuable chemicals from coal, natural gas, or biomass. During syngas conversion, sintering is known to deactivate the catalyst owing to the loss of active surface area. However, the growth of nanoparticles might induce the formation of new active sites such as grain boundaries (GBs) which perform differently from the original nanoparticles. Herein, we reported a unique Cu‐based catalyst, Cu nanoparticles with in situ generated GBs confined in zeolite Y (denoted as activated Cu/Y), which exhibited a high selectivity for C5+ hydrocarbons (65.3 C%) during syngas conversion. Such high selectivity for long‐chain products distinguished activated Cu/Y from typical copper‐based catalysts which mainly catalyze methanol synthesis. This unique performance was attributed to the GBs, while the zeolite assisted the stabilization through spatial confinement. Specifically, the GBs enabled H‐assisted dissociation of CO and subsequent hydrogenation into CHx*. CHx* species not only serve as the initiator but also directly polymerize on Cu GBs, known as the carbide mechanism. Meanwhile, the synergy of GBs and their vicinal low‐index facets led to the CO insertion where non‐dissociative adsorbed CO on low‐index facets migrated to GBs and inserted into the metal‐alkyl bond for the chain growth. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to analyze the factors influencing glycemic control in patients with type 2 diabetes mellitus (T2DM). Methods: Baseline data, encompassing basic information, lifestyle habits, and treatment of 305 T2DM patients from March 2021 to January 2023, were collected and analyzed using SPSS 26.0 software. Results: Univariate and multivariate logistic regression analyses identified insulin therapy (OR = 2.233; 95%Cl = 1.013–4.520; P = 0.026) and regular clinic visits (OR = 0.567; 95%Cl = 0.330–0.973; P = 0.040) as independent factors influencing glycemic control. No observed interactions between the two variables were noted. Conclusion: History of insulin therapy and regular clinic visits were significantly and independently associated with glycated hemoglobin control in T2DM patients. Tailored interventions based on individual circumstances are recommended to optimize glycemic control. [ABSTRACT FROM AUTHOR]

Syngas conversion serves as a gas‐to‐liquid technology to produce liquid fuels and valuable chemicals from coal, natural gas, or biomass. During syngas conversion, sintering is known to deactivate the catalyst owing to the loss of active surface area. However, the growth of nanoparticles might induce the formation of new active sites such as grain boundaries (GBs) which perform differently from the original nanoparticles. Herein, we reported a unique Cu‐based catalyst, Cu nanoparticles with in situ generated GBs confined in zeolite Y (denoted as activated Cu/Y), which exhibited a high selectivity for C5+ hydrocarbons (65.3 C%) during syngas conversion. Such high selectivity for long‐chain products distinguished activated Cu/Y from typical copper‐based catalysts which mainly catalyze methanol synthesis. This unique performance was attributed to the GBs, while the zeolite assisted the stabilization through spatial confinement. Specifically, the GBs enabled H‐assisted dissociation of CO and subsequent hydrogenation into CHx*. CHx* species not only serve as the initiator but also directly polymerize on Cu GBs, known as the carbide mechanism. Meanwhile, the synergy of GBs and their vicinal low‐index facets led to the CO insertion where non‐dissociative adsorbed CO on low‐index facets migrated to GBs and inserted into the metal‐alkyl bond for the chain growth. [ABSTRACT FROM AUTHOR]

Background: Contrast‐enhanced transcranial Doppler (cTCD) study has been established as one of the most common investigations for detecting right‐to‐left shunt (RLS). Although the conventional Valsalva maneuver (c‐VM) has been used to increase the sensitivity of cTCD for RLS, efforts are still needed to improve the detection rate further. We proposed a new provocation method with a syringe‐modified Valsalva maneuver (sm‐VM) during cTCD and compared the efficacy of this strategy with cTCD measured at resting and with the provocation of c‐VM. Methods: Consecutive patients with suspicion of RLS who underwent cTCD in our institution between September 27, 2021, and April 1, 2022, were included in this study. Examination of cTCD was performed separately at the resting state and provoked with c‐VM and sm‐VM. The overall proportion of patients with RLS and their distribution with different RLS grades were compared. Results: A total of 389 patients (mean age: 49.37 years, male: 52.2%) were included in this study. The positive rate for RLS was significantly higher for cTCD detected with sm‐VM than those detected at resting state and with c‐VM (46.8% vs. 21.6% and 34.2%, all p <.05). Besides, cTCD detected with sm‐VM was also associated with a higher proportion of patients with grade III RLS than those detected at resting state and with c‐VM (11.3% vs. 1.8% and 0%, all p <.05). Conclusions: Compared to cTCD detected at resting state and with c‐VM, cTCD with sm‐VM could further increase the positive detection rate of RLS. [ABSTRACT FROM AUTHOR]

Plants have evolved complex mechanisms to adapt to harsh environmental conditions. Rice (Oryza sativa) is a staple food crop that is sensitive to low temperatures. However, its cold stress responses remain poorly understood, thus limiting possibilities for crop engineering to achieve greater cold tolerance. In this study, we constructed a rice pan-transcriptome and characterized its transcriptional regulatory landscape in response to cold stress. We performed Iso-Seq and RNA-Seq of 11 rice cultivars subjected to a time-course cold treatment. Our analyses revealed that alternative splicing-regulated gene expression plays a significant role in the cold stress response. Moreover, we identified CATALASE C (OsCATC) and Os03g0701200 as candidate genes for engineering enhanced cold tolerance. Importantly, we uncovered central roles for the 2 serine-arginine-rich proteins OsRS33 and OsRS2Z38 in cold tolerance. Our analysis of cold tolerance and resequencing data from a diverse collection of 165 rice cultivars suggested that OsRS2Z38 may be a key selection gene in japonica domestication for cold adaptation, associated with the adaptive evolution of rice. This study systematically investigated the distribution, dynamic changes, and regulatory mechanisms of alternative splicing in rice under cold stress. Overall, our work generates a rich resource with broad implications for understanding the genetic basis of cold response mechanisms in plants. Pan-transcriptomic analysis of rice under cold stress reveals alternative splicing control of cold tolerance. [ABSTRACT FROM AUTHOR]

Pickering emulsion stabilized by lignin particles has many advantages such as high flexibility, natural non-toxicity, anti-oxidation, and anti-ultraviolet. In order to promote the application of industrial lignin in the field of Pickering emulsions, this study has done comparatively systematic and basic research on Pickering emulsions stabilized by lignin particles. The emulsification effects of lignin particles on cyclohexane and n-decanol which have opposite polarity were compared firstly under different oil-water ratios. It was found that stable emulsions formed when the three-phase contact angle of oil/water/lignin was closer to 90°. The weakly polar cyclohexane could be well-emulsified by lignin particles, while the strong polar n-decanol could not. Cyclohexane was used as the oil phase to discuss the emulsification ability of lignin particles under different concentrations or with different particle sizes. The results show increasing the concentration of lignin particles or reducing the particle size can improve the emulsification performance. [ABSTRACT FROM AUTHOR]

A porous microplate embedded with two nanocomposite piezoelectric layers is investigated in the current work. All three layers are functionally graded and completely attached to each other, and the microstructure lies on a bi-parameter elastic foundation that withstands shear and normal forces simultaneously. Also, an external voltage is subjected to the piezoelectric patches. The mentioned patches are reinforced with carbon nanotubes to enhance their electro-mechanical performance. A higher-order shear deformation theory and von Karman's assumptions are hired to demonstrate the kinematic relations. Next, applying Hamilton's principle and variational technique, the governing motion equations are derived with the help of the modified couple stress theory to capture the scale influence. To solve the system of differential equations, a closed-form Navier method is employed, and by ensuring the correctness of the results, then it turns to investigate the impact of different factors including porosity percentage and also pores' distribution patterns, nanotubes dispersion patterns, and other important factors on the natural frequencies of the model. Obtained results show that symmetric and uniform porosity distributions have the maximum and minimum amounts of natural frequencies. Moreover, the maximum difference between natural frequencies of three different porosity distribution occurs in e0 = 0.95 and is approximately 32%. The current study results may consider to design and produce smart structures and devices with improved performance. [ABSTRACT FROM AUTHOR]

Cytokines are small signaling proteins that regulate the immune responses to infection and tissue damage. Surface charges of cytokines determine their in vivo fate in immune regulation, e.g., half-life and distribution. The overall negative charges in the extracellular microenvironment and the acidosis during inflammation and infection may differentially impact cytokines with different surface charges for fine-tuned immune regulation via controlling tissue residential properties. However, the trend and role of cytokine surface charges has yet to be elucidated in the literature. Interestingly, we have observed that most pro-inflammatory cytokines have a negative charge, while most anti-inflammatory cytokines and chemokines have a positive charge. In this review, we extensively examined the surface charges of all cytokines and chemokines, summarized the pharmacokinetics and tissue adhesion of major cytokines, and analyzed the link of surface charge with cytokine biodistribution, activation, and function in immune regulation. Additionally, we identified that the general trend of charge disparity between pro- and anti-inflammatory cytokines represents a unique opportunity to develop precise immune modulation approaches, which can be applied to many inflammation-associated diseases including solid tumors, chronic wounds, infection, and sepsis. [Display omitted] • Majority of pro-inflammatory cytokines are negatively charged. • Majority of anti-inflammatory cytokines are positively charged. • Charge disparity may indirectly regulate cytokines in inflammation via altering their tissue residence and half-lives. • Targeting the charge disparity of cytokines may provide a novel mechanism for immune modulation. [ABSTRACT FROM AUTHOR]

Neuropeptides are crucial in regulation of a rich variety of developmental, physiological, and behavioral functions throughout the life cycle of insects. Using an integrated approach of multiomics, we identified neuropeptide precursors in the greater wax moth Galleria mellonella, which is a harmful pest of honeybee hives with a worldwide distribution. Here, a total of 63 and 67 neuropeptide precursors were predicted and annotated in the G. mellonella genome and transcriptome, in which 40 neuropeptide precursors were confirmed in the G. mellonella peptidome. Interestingly, we identified 12 neuropeptide precursor genes present in G. mellonella but absent in honeybees, which may be potential novel pesticide target sites. Honeybee hives were contaminated with heavy metals such as lead, enabling its bioaccumulation in G. mellonella bodies through the food chain, we performed transcriptome sequencing to analyze the effects of Pb stress on the mRNA expression level of G. mellonella neuropeptide precursors. After treatment by Pb, the expression of neuropeptide F1 was found to be significantly downregulated, implying that this neuropeptide might be associated with responding to the heavy metal stress in G. mellonella. This study comprehensively identified neuropeptide precursors in G. mellonella, and discussed the effects of heavy metals on insect neuropeptides, with the example of G. mellonella. The results are valuable for future elucidation of how neuropeptides regulate physiological functions in G. mellonella and contribute to our understanding of the insect's environmental plasticity and identify potential new biomarkers to assess heavy metal toxicity in insects. [ABSTRACT FROM AUTHOR]

Autophagy is recognized as a promising therapeutic target for traumatic brain injury (TBI). Crocetin is an aglycone of crocin naturally occurring in saffron and has been found to alleviate brain injury diseases. However, whether crocetin affects autophagy after TBI remains unknown. Therefore, we explore crocetin roles in autophagy after TBI. We used a weight-dropped model to induce TBI in C57BL/6J mice. Neurological severity scoring (NSS) and grip tests were used to evaluate the neurological level of injury. Brain edema, neuronal apoptosis, neuroinflammation and autophagy were detected by measurements of brain water content, TUNEL staining, ELISA kits and western blotting. Crocetin ameliorated neurological dysfunctions and brain edema after TBI. Crocetin reduced neuronal apoptosis and neuroinflammation and enhanced autophagy after TBI. Crocetin alleviates TBI by inhibiting neuronal apoptosis and neuroinflammation and activating autophagy. [ABSTRACT FROM AUTHOR]

Machine learning (ML) is increasingly being used to guide biological discovery in biomedicine such as prioritizing promising small molecules in drug discovery. In those applications, ML models are used to predict the properties of biological systems, and researchers use these predictions to prioritize candidates as new biological hypotheses for downstream experimental validations. However, when applied to unseen situations, these models can be overconfident and produce a large number of false positives. One solution to address this issue is to quantify the model's prediction uncertainty and provide a set of hypotheses with a controlled false discovery rate (FDR) pre-specified by researchers. We propose CPEC, an ML framework for FDR-controlled biological discovery. We demonstrate its effectiveness using enzyme function annotation as a case study, simulating the discovery process of identifying the functions of less-characterized enzymes. CPEC integrates a deep learning model with a statistical tool known as conformal prediction, providing accurate and FDR-controlled function predictions for a given protein enzyme. Conformal prediction provides rigorous statistical guarantees to the predictive model and ensures that the expected FDR will not exceed a user-specified level with high probability. Evaluation experiments show that CPEC achieves reliable FDR control, better or comparable prediction performance at a lower FDR than existing methods, and accurate predictions for enzymes under-represented in the training data. We expect CPEC to be a useful tool for biological discovery applications where a high yield rate in validation experiments is desired but the experimental budget is limited. Author summary: Machine learning (ML) models are increasingly being applied as predictors to generate biological hypotheses and guide biological discovery. However, when applied to unseen situations, ML models can be overconfident and make enormous false positive predictions, resulting in the challenges for researchers to trade-off between high yield rates and limited budgets. One solution is to quantify the model's prediction uncertainty and generate predictions at a controlled false discovery rate (FDR) pre-specified by researchers. Here, we introduce CPEC, an ML framework designed for FDR-controlled biological discovery. Using enzyme function prediction as a case study, we simulate the process of function discovery for less-characterized enzymes. Leveraging a statistical framework, conformal prediction, CPEC provides rigorous statistical guarantees that the FDR of the model predictions will not surpass a user-specified level with high probability. Our results suggested that CPEC achieved reliable FDR control for enzymes under-represented in the training data. In the broader context of biological discovery applications, CPEC can be applied to generate high-confidence hypotheses and guide researchers to allocate experimental resources to the validation of hypotheses that are more likely to succeed. [ABSTRACT FROM AUTHOR]

As a key factor in determining testis size and sperm number, sertoli cells (SCs) play a crucial role in male infertility. Heat stress (HS) reduces SCs counts, negatively impacting nutrient transport and supply to germ cells, and leading to spermatogenesis failure in humans and animals. However, how HS affects the number of SCs remains unclear. We hypothesized that changes in SC metabolism contribute to the adverse effects of HS. In this study, we first observed an upregulation of arachidonic acid (AA), an unsaturated fatty acid after HS exposure by LC-MS/MS metabolome detection. By increasing ROS levels, expression of KEAP1 and NRF2 proteins as well as LC3 and LAMP2, 100 µM AA induced autophagy in SCs by activating oxidative stress (OS). We observed adverse effects of AA on mitochondria under HS with a decrease of mitochondrial number and an increase of mitochondrial membrane potential (MMP). We also found that AA alternated the oxygen transport and absorption function of mitochondria by increasing glycolysis flux and decreasing oxygen consumption rate as well as the expression of mitochondrial electron transport chain (ETC) proteins Complex I, II, V. However, pretreatment with 5 mM NAC (ROS inhibitor) and 2 µM Rotenone (mitochondrial ETC inhibitor) reversed the autophagy induced by AA. In summary, AA modulates autophagy in SCs during HS by disrupting mitochondrial ETC function, inferring that the release of AA is a switch-like response, and providing insight into the underlying mechanism of high temperatures causing male infertility. [ABSTRACT FROM AUTHOR]

Wide‐bandgap (WBG) perovskite solar cell (PSC) plays a pivotal role as the top subcell in all‐perovskite tandem solar cells (TSCs), facilitating the absorption of high‐energy photons and affording a large open‐circuit voltage (VOC). Nonetheless, the stability and efficiency of WBG PSCs are constrained by light‐induced halide segregation and non‐radiative recombination losses. In this study, this work presents an approach of utilizing 2‐methylpiperazinium bromide (2‐MePBr) via interfacial engineering to realize high‐efficiency WBG (1.77 eV) PSCs. The C─NH─C functional group in 2‐MePBr, serving as an electron donor, can interact with under‐coordinated lead defects at the perovskite surface. Consequently, the treatment with 2‐MePBr mitigates interfacial non‐radiative recombination, enhances charge transport, inhibits ion migration, and thus delivers an improved power conversion efficiency (PCE) of 19.30% with a VOC of 1.29 V, and a fill factor of 83.08%. Notably, the WBG PSCs manifest enhanced stability, preserving 80% of the initial PCE after 337 h of continuous operation under 1 sun illumination at the maximum power point. Furthermore, the all‐perovskite TSCs based on this WBG subcell achieve a PCE of 27.47%, showing its promising application in perovskite‐based tandem solar cells. [ABSTRACT FROM AUTHOR]

Diabetic cardiomyopathy (DCM) is a prevalent complication of type 2 diabetes (T2D). 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) is a glycolysis regulator. However, the potential effects of PFKFB3 in the DCM remain unclear. In comparison to db/m mice, PFKFB3 levels decreased in the hearts of db/db mice. Cardiac-specific PFKFB3 overexpression inhibited myocardial oxidative stress and cardiomyocyte apoptosis, suppressed mitochondrial fragmentation, and partly restored mitochondrial function in db/db mice. Moreover, PFKFB3 overexpression stimulated glycolysis. Interestingly, based on the inhibition of glycolysis, PFKFB3 overexpression still suppressed oxidative stress and apoptosis of cardiomyocytes in vitro, which indicated that PFKFB3 overexpression could alleviate DCM independent of glycolysis. Using mass spectrometry combined with co-immunoprecipitation, we identified optic atrophy 1 (OPA1) interacting with PFKFB3. In db/db mice, the knockdown of OPA1 receded the effects of PFKFB3 overexpression in alleviating cardiac remodeling and dysfunction. Mechanistically, PFKFB3 stabilized OPA1 expression by promoting E3 ligase NEDD4L-mediated atypical K6-linked polyubiquitination and thus prevented the degradation of OPA1 by the proteasomal pathway. Our study indicates that PFKFB3/OPA1 could be potential therapeutic targets for DCM. [ABSTRACT FROM AUTHOR]

The stochastic computing (SC) has been proven to be an energy-efficient way to perform neural network. In this study, we propose a field-free voltage-controlled spintronics SC system based on the magnetic tunnel junction (MTJ). We observe a stochastic switching behavior of the MTJ and that it could be controlled by the voltage applied on the device. The voltage-controlled stochastic switching behavior is used to encode numbers ranging from 0 to 1 into a series of random bit-streams in the SC system. Furthermore, the handwritten recognition task is performed on the MTJ-based SC system, achieving a 95% maximum accuracy, which is comparable with the floating-point based neural network. Our work provides inspiration for the energy-efficient neural network systems. [ABSTRACT FROM AUTHOR]

Phase distribution is crucial for obtaining the whole information of phase object in imaging. However, due to the transparency of phase objects, the phase distribution cannot be obtained in traditional bright-field imaging. Here, we propose a phase distribution reconstruction based on the imaginary value of weak measurement, which is achieved by a Pancharatnam–Berry phase metasurface. Moreover, by adjusting the weak value to a real weak value, amplitude reconstruction can also be achieved. Different parts of weak values can be obtained by controlling the preselection and postselection states. The weak interaction is achieved by the metasurface, which is convenient to control the weak coupling and reduce the complexity of the experimental setup at the same time. Furthermore, the edge contour of objects can also be acquired by the weak measurement, and the edge sharpness is related to types of the weak values, which plays an important role in image resolution. Our method paves a way for quantitative phase imaging and unlabeled biological imaging. [ABSTRACT FROM AUTHOR]

Actuators utilizing snap‐through instabilities are widely investigated for high‐performance fast actuators and shape reconfigurable structures owing to their rapid response and limited reliance on continuous energy input. However, prevailing approaches typically involve a combination of multiple bistable actuator units and achieving multistability within a single actuator unit still remains an open challenge. Here, a soft actuator is presented that uses shape memory alloy (SMA) and mixed‐mode elastic instabilities to achieve intrinsically multistable shape reconfiguration. The multistable actuator unit consists of six stable states, including two pure bending states and four bend‐twist states. The actuator is composed of a pre‐stretched elastic membrane placed between two elastomeric frames embedded with SMA coils. By controlling the sequence and duration of SMA activation, the actuator is capable of rapid transition between all six stable states within hundreds of milliseconds. Principles of energy minimization are used to identify actuation sequences for various types of stable state transitions. Bending and twisting angles corresponding to various prestretch ratios are recorded based on parameterizations of the actuator's geometry. To demonstrate its application in practical conditions, the multistable actuator is used to perform visual inspection in a confined space, light source tracking during photovoltaic energy harvesting, and agile crawling. [ABSTRACT FROM AUTHOR]

The defluoroborylation of fluoroarenes by chromium-catalyzed cleavage of unactivated C–F bonds is described. The reaction uses HBpin as the boron source, low-cost and commercially available chromium salt as the precatalyst, and terpyridine as a crucial ligand, providing a protocol with atom-efficient benefits and a wide range of applicable substrates for the functionalization of aryl C–F bonds. Preliminary mechanistic studies indicate that an unprecedented Cr-catalyzed magnesiation of the unactivated C–F bond occurred. The generated arylmagnesium intermediates then participated in the subsequent borylation reaction. The application of the strategy in the preparation of valuable derivatives is demonstrated by the late-stage functionalization of boronate ester groups. [ABSTRACT FROM AUTHOR]

Nucleic acid modifications play essential roles in diverse biological processes, ranging from gene expression regulation to stress response. While traditional research focused on common modifications like methylation, recent discoveries are unveiling a wide range of rare modifications with potentially crucial functions. However, accurately detecting and mapping these modifications pose significant challenges due to their low abundance and diverse chemical properties. This article summarizes the recent discoveries of rare DNA and RNA modifications across various organisms, highlighting their potential biological significance. Furthermore, it critically evaluates the limitations of current mapping techniques, including potential sources of false positives and negatives. Finally, the article discusses emerging strategies for overcoming these challenges and future opportunities in the field of rare nucleic acid modification detection. [ABSTRACT FROM AUTHOR]

Land public transport is an important link within and between cities, and how to control the transmission of COVID-19 in land public transport is a critical issue in our daily lives. However, there are still many inconsistent opinions and views about the spread of SARS-CoV-2 in land public transport, which limits our ability to implement effective interventions. The purpose of this review is to overview the literature on transmission characteristics and routes of the epidemic in land public transport, as well as to investigate factors affecting its spread and provide feasible measures to mitigate the infection risk of passengers. We obtained 898 papers by searching the Web of Science, Pubmed, and WHO global COVID database by keywords, and finally selected 45 papers that can address the purpose of this review. Land public transport is a high outbreak area for COVID-19 due to characteristics like crowding, inadequate ventilation, long exposure time, and environmental closure. Different from surface touch transmission and drop spray transmission, aerosol inhalation transmission can occur not only in short distances but also in long distances. Insufficient ventilation is the most important factor influencing long-distance aerosol transmission. Other transmission factors (e.g., interpersonal distance, relative orientation, and ambient conditions) should be noticed as well, which have been summarized in this paper. To address various influencing factors, it is essential to suggest practical and efficient preventive measures. Among these, increased ventilation, particularly the fresh air (i.e., natural ventilation), has proven to effectively reduce indoor infection risk. Many preventive measures are also effective, such as enlarging social distance, avoiding faceto-face orientation, setting up physical partitions, disinfection, avoiding talking, and so on. As research on the epidemic has intensified, people have broken down many perceived barriers, but more comprehensive studies on monitoring systems and prevention measures in land public transport are still needed. [ABSTRACT FROM AUTHOR]