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The metal–insulator transition (MIT) of vanadium dioxide (VO2), which involves significant changes in electrical, optical, and other properties, has attracted widespread attention. Here, we report a triboelectric nanogenerator (TENG)-based self-powered VO2 phase transition. With the TENG-induced ionic gel gating, the hydrogen ion insertion/detachment in the VO2 lattice can be modulated at room temperature to cause phase transitions that control light transmittance. The phase transition behavior is characterized by X-ray diffraction and Raman spectroscopy. Under the continuous power supply from TENG, the X-ray diffraction peak of VO2 shifts, and the Raman intensities of characteristic peaks decrease, accompanied by a color change from brown to translucent. The electrical conductivity undergoes a significant change by two orders of magnitude and persists overnight, indicating an excellent duration of the phase transition. In addition, a raindrop TENG-induced VO2 phase transition is demonstrated. The infrared transmittance of VO2 is decreased dramatically by 28.1% due to the phase transition, achieving a heat preservation effect that holds promise for adaptive thermal insulation in smart windows during rainfall through raindrop power generation. This work has realized the TENG-based self-powered VO2 phase transition, holding significant application potential in smart homes. [ABSTRACT FROM AUTHOR]

Cardiac electromechanics is a coupled multiphysics and multiscale problem. Of great interest to medicine and pharmacology is how the heart responds to changes in ion channel dynamics within the myocyte that are either caused by disease or by the administration of drugs. A successful model of cardiac mechanical response must therefore incorporate a first-principles description of electrophysiology of the cardiac myocyte including intracellular calcium dynamics, transmembrane ionic currents and action potential (AP) formation at the cellular level. This article reviews the evolution of electrophysiological models of cardiac ventricular myocytes in terms of coupled differential equations whose state variables include ion channel gating parameters, intracellular ionic concentrations and the membrane voltage. The myocytes are connected through gap junctions forming fibers, which in turn connect to form cardiac tissues. The electromechanical response of cardiac tissues is coupled through intracellular calcium dynamics and stretch induced/ modulated currents, and can be solved using suitable discretization schemes under appropriate initial and boundary conditions. We discuss in detail the single-cell dynamics of the ORd model of human ventricular myocytes and describe the propagation of AP in periodically paced 1D fibers and 2D tissues. The origin of tissue-level diseased conditions in altered subcellular dynamics are discussed. [ABSTRACT FROM AUTHOR]

Isoprene, a volatile hydrocarbon, is typically emitted from the leaves of many plant species. Given its well‐known function in plant growth and defense aboveground, we examined its effects on root physiology. We used isoprene‐emitting (IE) lines and a non‐emitting (NE) line of Arabidopsis and investigated their performance by analyzing root phenotype, hormone levels, transcriptome, and metabolite profiles under both normal and salt stress conditions. We show that IE lines emitted tiny amounts of isoprene from roots and showed an increased root/shoot ratio compared with NE line. Isoprene emission exerted a noteworthy influence on hormone profiles related to plant growth and stress response, promoting root development and salt‐stress resistance. Methyl erythritol 4‐phosphate pathway metabolites, precursors of isoprene and hormones, were higher in the roots of IE lines than in the NE line. Transcriptome data indicated that the presence of isoprene increased the expression of key genes involved in hormone metabolism/signaling. Our findings reveal that constitutive root isoprene emission sustains root growth under saline conditions by regulating and/or priming hormone biosynthesis and signaling mechanisms and expression of key genes relevant to salt stress defense. [ABSTRACT FROM AUTHOR]

Windows are an important part of buildings and transmit light between indoors and outdoors. Frequent heat exchange through windows increases building energy consumption. Smart windows can change optical properties and modulate solar radiation, which are recognized as frontrunners in building energy saving. Among various smart windows, thermochromic windows usually passively regulate light transmittance in response to environmental temperature and have showed great potential for practical applications. Thermochromic materials are key to constructing thermochromic smart windows. Usually, a reversible phase transition takes place for thermoresponsive materials near the critical transition temperature, leading to changes in transmittance over different spectrum bands. Representative thermochromic materials include metal oxides, hydrogels, perovskites, ionic liquids, liquid crystals, etc. The intrinsic phase transition temperature, luminous transmittance, and solar modulation ability are among the critical parameters defining the performance of smart windows. New strategies have been developed to modulate the performance of thermochromic materials and smart windows to meet demands from different environments and climates. Such endeavors have boosted smart windows to modulate fullspectrum solar regulation and to achieve efficient all-climate building energy saving. Next generation smart windows will not only modulate solar transmission, but also convert and store solar energy through new power technologies such as thermoelectricity conversion and solar cells. Challenges and future prospects of smart windows are discussed to inspire future building energy saving. [ABSTRACT FROM AUTHOR]

Bone destruction, a major source of morbidity, is mediated by heightened differentiation and activity of osteoclasts (OC), highly specialized multinucleated myeloid cells endowed with unique bone-resorptive capacity. The molecular mechanisms regulating OC differentiation in the bone marrow are still partly elusive. Here, we aimed to identify new regulatory circuits and actionable targets by comprehensive proteomic characterization of OCgenesis from mouse bone marrow monocytes, adopting two parallel unbiased comparative proteomic approaches. This work disclosed an unanticipated protein signature of OCgenesis, with most gene products currently unannotated in bone-related functions, revealing broad structural and functional cellular reorganization and divergence from macrophagic immune activity. Moreover, we identified the deubiquitinase UCHL1 as the most upregulated cytosolic protein in differentiating OCs. Functional studies proved it essential, as UCHL1 genetic and pharmacologic inhibition potently suppressed OCgenesis. Furthermore, proteomics and mechanistic dissection showed that UCHL1 supports OC differentiation by restricting the anti-OCgenic activity of NRF2, the transcriptional activator of the canonical antioxidant response, through redox-independent stabilization of the NRF2 inhibitor, KEAP1. Besides offering a valuable experimental framework to dissect OC differentiation, our study discloses the essential role of UCHL1, exerted through KEAP1-dependent containment of NRF2 anti-OCgenic activity, yielding a novel potential actionable pathway against bone loss. [ABSTRACT FROM AUTHOR]

High moisture content, low ventilation levels, and changes in the hygrothermal design of wooden dwellings could generate environmental conditions favorable for developing the rot fungus Serpula lacrymans, which is known as the most destructive fungus of its kind. The purpose of this research was to develop an experimental methodology to determine the conditions of the appearance of the fungus S. lacrymans, through in situ measurement of biological and environmental frequency indicators for wooden dwellings in South Central Chile. The referential standards for the appearance of the fungus were determined based on specialized literature and measurements of dwellings with and without deterioration. The frequency indicators for the appearance of the fungus defined and studied were as follows: frequency of air temperature FATs (%), frequency of relative humidity FRMs (%), frequency of ventilation rate FVRs (%), and rot fungus spore concentrations (CFU/pp). The methodology was validated by being measured in various enclosures and spaces under the floor in wooden dwellings in the cities of Valdivia and Temuco. The results confirmed the strong relationship between environmental relative humidity frequencies, ventilation levels, and spore concentration regarding the appearance of the fungus, where the growth dynamics cannot be separately explained without a previous analysis of the variables. In general, the dwellings most affected by the presence of the fungus had the greatest moisture levels, lower ventilation levels, and greater spore concentration. This study is the basis to diagnose the phenomena of the appearance of the rot fungus in wooden dwellings in climates favorable for its development. [ABSTRACT FROM AUTHOR]

Huang, W.; Li, S.; Lu, Y., and Zhang, R., 2024. Hydrodynamic characteristics of an ecological revetment cavity structure under the propagation of ship-generated waves in a restricted channel. Journal of Coastal Research, 40(2), 382–394. Charlotte (North Carolina), ISSN 0749-0208. With the rapid development of inland waterway transportation and the rapid increase of ship traffic in restricted channels, the role of ship-generated waves on the restricted channel shore slope becomes increasingly significant. Some river bank protection projects use cavity structures to prevent bank slopes from being scoured and have achieved remarkable results. However, the hydrodynamic characteristics under the action of ship traveling waves inside and outside the cavity are not yet clear. Thus, this paper studies the time and frequency domain characteristics of ship-generated wave fluctuations, flow velocity distribution characteristics, and turbulence distribution characteristics in the cavity, under the action of ship-generated waves, by conducting self-propelled ship model flume tests using a new type of cavity shore protection structure applied to a restricted channel. This study investigates the application of such a structure to shallow water coastal areas with frequent ship traffic. The corresponding results demonstrate that during the ship traveling wave transfer to the cavity, the fluctuation frequency did not change significantly, and fluctuation energy concentrated in the frequency range of 0–1.5 Hz. The high-frequency (0.40–1.5 Hz) energy is concentrated in the secondary wave process, and the low-frequency (0–0.40 Hz) energy is observed throughout the fluctuation process. The cavity structure changes the flow velocity from low-frequency periodic flow to high-frequency oscillatory flow, and the frequency of flow velocity change tends to be uniformly distributed with significantly enhanced turbulence. The cavity's maximum wave height, flow velocity, and turbulence energy positively correlate with the self-propelled velocity of the vessel Vc. Moreover, the characteristic values increase slowly for Vc in the subcritical velocity region (Frh < 0.84), and the characteristic values increase sharply for Vc in the transcritical velocity region (0.84 < Frh < 1.12). [ABSTRACT FROM AUTHOR]

Use of electrode materials that show phase change behavior and hence drastic changes in electrochemical activity during operation has not been explored for Li-ion batteries. Here we demonstrate the vanadium oxide (VO2) cathode that undergoes a metal–insulator transition due to the first-order structural phase transition at an accessible temperature of 68 °C for battery operation. Using a suitable electrolyte operable across the phase transition range and compatible with vanadium oxide cathodes, we studied the effect of cathode active material structural changes on lithium insertion followed by the electrochemical characteristics above and below the phase transition temperature. The high-temperature VO2 phase shows significantly improved capacitance, enhanced current rate capabilities, improved electrical conductivity and lithium-ion diffusivity compared to the insulating low temperature phase. This opens up new avenues for electrode design, allowing manipulation of electrochemical reactions around phase transition temperatures, and in particular enhancing electrochemical properties at elevated temperatures contrary to the existing class of battery chemistries that lead to performance deterioration at elevated temperatures. [ABSTRACT FROM AUTHOR]

The metal–insulator transition (MIT) observed in vanadium dioxide has been a topic of great research interest for past decades, with the underlying physics yet not fully understood due to the complex electron interactions and structures involved. The ability to understand and tune the MIT behavior is of vital importance from the perspective of both underlying fundamental science as well as potential applications. In this work, scanning transmission electron microscopy (STEM) is used to investigate cross‐section lamella of the VO2 films deposited using pulsed laser deposition on three substrates: c‐cut sapphire, TiO2(101) and TiO2(001). Advanced STEM imaging is performed in which also the oxygen atom columns are resolved. The overall film quality and structures on atomic and nanoscale are linked to the electrical transition characteristics. Relatively poor MIT characteristics are observed on c‐sapphire due to the presence of very small domains with six orientation variants, and on TiO2 (001) due to the presence of cracks induced by stress relaxation. However, the MIT on TiO2 (101) behaves favorably, despite similar stress relaxation which, however, only leads to domain boundaries but no cracks. [ABSTRACT FROM AUTHOR]

The primary objective of this study is to investigate the influence of thermal stratification on the magnetohydrodynamics (MHD) flow of water-based nano, hybrid, and ternary hybrid nanofluids, as they pass a vertically stretching cylinder within a porous media. The nanoparticles Cu,Al2O3, and TiO2 are suspended in a base fluid H2O, leading to the formation of a ternary hybrid nanofluid (Cu + Al2O3 + TiO2/H2O). The use of a relevant similarity variable has been utilized to simplify the boundary layer equations which control the flow and transform the coupled nonlinear partial differential equations into a collection of nonlinear ordinary differential equations. The numerical results are calculated with the 3-stage Lobatto IIIa approach, specifically implemented by Bvp4c in MATLAB. This study presents a graphical and numerical analysis of the effects of various non-dimensional parameters, such as the Prandtl number, radiation parameter, heat source/sink parameter, magnetic parameter, porosity parameter, curvature parameter, thermal stratification parameter, and thermal buoyancy parameter, on the velocity, temperature, skin-friction coefficient, and Nusselt number. The impacts of these parameters are visually depicted through graphs and quantitatively represented in tables. The ternary hybrid nanofluid has a higher heat transfer rate than the hybrid nanofluid, and the hybrid nanofluid has a higher heat transfer rate than ordinary nanofluids. [ABSTRACT FROM AUTHOR]

Ultrafast spectroscopy can be used to study dynamic processes on femtosecond to nanosecond timescales, but is typically used for photoinduced processes. Several materials can induce ultrafast temperature rises upon absorption of femtosecond laser pulses, in principle allowing to study thermally activated processes, such as (catalytic) reactions, phase transitions, and conformational changes. Gold-silica core-shell nanoparticles are particularly interesting for this, as they can be used in a wide range of media and are chemically inert. Here we computationally model the temporal and spatial temperature profiles of gold nanoparticles with and without silica shell in liquid and gas media. Fast rises in temperature within tens of picoseconds are always observed. This is fast enough to study many of the aforementioned processes. We also validate our results experimentally using a poly(urethane-urea) exhibiting a temperature-dependent hydrogen bonding network, which shows local temperatures above 90 °C are reached on this timescale. Moreover, this experiment shows the hydrogen bond breaking in such polymers occurs within tens of picoseconds., (© 2024 The Authors. ChemPlusChem published by Wiley-VCH GmbH.)

Anthocyanin is a type of plant secondary metabolite beneficial to human health. The anthocyanin content of vegetable and fruit crops signifies their nutritional quality. However, the molecular mechanism of anthocyanin accumulation, especially tissue-specific accumulation, in Caitai, as well as in other Brassica rapa varieties, remains elusive. In the present study, taking advantage of three kinds of Caitai cultivars with diverse colour traits between leaves and stems, we conducted a comparative transcriptome analysis and identified the molecular pathway of anthocyanin biosynthesis in Caitai leaves and stems, respectively. Our further investigations demonstrate that bHLH42, which is robustly induced by MeJA, closely correlates with tissue-specific accumulation of anthocyanins in Caitai; bHLH42 upregulates the expression of flavonoid/anthocyanin biosynthetic pathway genes to activate anthocyanin biosynthesis pathway, importantly, overexpression of bHLH42 significantly improves the anthocyanin content of Caitai. Our analysis convincingly suggests that bHLH42 induced by jasmonic acid signalling plays a crucial role in tissue-specific accumulation of anthocyanins in Caitai., (© 2024 The Author(s). Physiologia Plantarum published by John Wiley & Sons Ltd on behalf of Scandinavian Plant Physiology Society.)

Interspecific information flow is known to affect individual fitness, population dynamics and community assembly, but there has been less study of how species diversity affects information flow and thereby ecosystem functioning and services. We address this question by first examining differences among species in the sensitivity, accuracy, transmissibility, detectability and value of the cues and signals they produce, and in how they receive, store and use information derived from heterospecifics. We then review how interspecific information flow occurs in communities, involving a diversity of species and sensory modes, and how this flow can affect ecosystem-level functions, such as decomposition, seed dispersal or algae removal on coral reefs. We highlight evidence that some keystone species are particularly critical as a source of information used by eavesdroppers, and so have a disproportionate effect on information flow. Such keystone species include community informants producing signals, particularly about predation risk, that influence other species' landscapes of fear, and aggregation initiators creating cues or signals about resources. We suggest that the presence of keystone species means that there will likely be a positive relationship in many communities between species diversity and information through a 'sampling effect', in which larger pools of species are more likely to include the keystone species by chance. We then consider whether the number and relative abundance of species, irrespective of the presence of keystone species, matter to interspecific information flow; on this issue, the theory is less developed, and the evidence scant and indirect. Higher diversity could increase the quantity or quality of information that is used by eavesdroppers because redundancy increases the reliability of information or because the species provide complementary information. Alternatively, there could be a lack of a relationship between species diversity and information if there is widespread information parasitism where users are not sources, or if information sourced from heterospecifics is of lower value than that gained personally or sourced from conspecifics. Recent research suggests that species diversity does have information-modulated community and ecosystem consequences, especially in birds, such as the diversity of species at feeders increasing resource exploitation, or the number of imitated species increasing responses to vocal mimics. A first step for future research includes comprehensive observations of information flow among different taxa and habitats. Then studies should investigate whether species diversity influences the cumulative quality or quantity of information at the community level, and consequently ecosystem-level processes. An applied objective is to conserve species in part for their value as sources of information for other species, including for humans., (© 2024 Cambridge Philosophical Society.)

Fluorine MRI is finding wider acceptance in theranostics applications where imaging of 19 F hotspots of fluorinated contrast material is central. The essence of such applications is to capture ghosting-artifact-free images of the inherently low MR response under clinically viable conditions. To serve this purpose, this work introduces the balanced spiral spectroscopic imaging (BaSSI) sequence, which is implemented on a 3.0 T clinical scanner and is capable of generating 19 F hotspot images in an efficient manner. The sequence utilizes an all-phase-encoded pseudo-spiral k-space trajectory, enabling the acquisition of broadband (80 ppm) fluorine spectra free from chemical shift ghosting. BaSSI can acquire a 64 × 64 image with 1 mm × 1 mm voxels in just 14 s, significantly outperforming typical MRSI sequences used in 1 H or 31 P imaging. The study employed in silico characterization to verify essential design choices such as the excitation pulse, as well as to identify the boundaries of the parameter space explored for optimization. BaSSI's performance was further benchmarked against the 3D ultrashort-echo-time balanced steady-state free precession (3D UTE BSSFP) sequence, a well established method used in 19 F MRI, in vitro. Both sequences underwent extensive optimization through exploration of a wide parameter space on a small phantom containing 10 μL of non-diluted bulk perfluorooctylbromide (PFOB) prior to comparative experiments. Subsequent to optimization, BaSSI and 3D UTE BSSFP were employed to capture images of small non-diluted bulk PFOB samples (0.10 and 0.05 μL), with variations in the number of signal averages, and thus the total scan time, in order to assess the detection sensitivities of the sequences. In these experiments, the detection sensitivity was evaluated using the Rose criterion (R c ), which provides a quantitative metric for assessing object visibility. The study further demonstrated BaSSI's utility as a (pre)clinical tool through postmortem imaging of polymer microspheres filled with PFOB in a BALB/c mouse. Anatomic localization of 19 F hotspots was achieved by denoising raw data obtained with BaSSI using a filter based on the Rose criterion. These data were then successfully registered to 1 H anatomical images. BaSSI demonstrated superior detection sensitivity in the benchmarking analysis, achieving R c values approximately twice as high as those obtained with the 3D UTE BSSFP method. The technique successfully facilitated imaging and precise localization of 19 F hotspots in postmortem experiments. However, it is important to highlight that imaging 10 mM PFOB in small mice postmortem, utilizing a 48 × 48 × 48 3D scan, demanded a substantial scan time of 1 h and 45 min. Further studies will explore accelerated imaging techniques, such as compressed sensing, to enhance BaSSI's clinical utility., (© 2023 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.)