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The stomatal response to red light appears to link stomatal conductance (g s) with photosynthetic rates. Initially, it was suggested that changes in intercellular CO2 concentration (C i) provide the main cue via a C i - dependent response. However, evidence for C i-independent mechanisms suggests an additional, more direct relationship with photosynthesis. While both C i-dependent and -independent mechanisms clearly function in stomatal red light responses, little is known regarding their relative contribution. The present study aimed to quantify the relative magnitude of C i-dependent and -independent mechanisms on the stomatal red light response, to characterize their interplay and to assess the putative link between plastoquinone redox state and C i-independent stomatal responses. Red light response curves measured at a range of C i values for wild-type Arabidopsis (Col-0) and the CO2 hyposensitive mutant ca1ca4 allowed deconvolution of C i-dependent and -independent pathways. Surprisingly, we observed that both mechanisms contribute equally to stomatal red light responses, but C i-independent stomatal opening is suppressed at high C i. The present data are also consistent with the involvement of the plastoquinone redox state in coordinating the C i - independent component. Overall, it seems that while C i-independent mechanisms are distinct from responses to C i, interplay between these two pathways is important to facilitate effective coordination between g s and photosynthesis. [ABSTRACT FROM AUTHOR]

An improved transfer matrix method is developed with modular matrices for rectangular electric and magnetic vector potentials, as well as the δ-function like potentials. As an example, the spin-dependent conductance in two-dimensional electron gas under modulation of two magnetic barriers are recalculated and compared with those illustrated in (Wang et al. Chin. Phys. B 19, 037301(2010)). The previous results are found inaccurate, their transfer matrix was derived for slowly varying magnetic vector potential, which is inappropriate for δ-function like Zeeman interaction potentials. Furthermore, the last transfer matrix of eq. (4) is also found incorrect, and the Zeeman interaction is wrongly expressed and mistakenly enhanced about (1/0.067 ≈ 15) times. Our improved method here is general and is demonstrated very fast forevaluating various spin-dependent transport properties in complex hybrid magnetic–electric structures. [ABSTRACT FROM AUTHOR]

Three types of hydrangea, Hydrangea areborescense ‘Annabelle’ (A), Hydrangea paniculata ‘Vanilla Strawberry’(B), and Hydrangea macrophylla ‘Endless Summer’ (C) were used as experimental materials, during the natural cooling process in the open field of Beijing, the differences in cold tolerance of Hydrangea were studied by measuring the survival rate of the following year, the relative conductance of leaves, soluble sugar, soluble protein, and relative water content under three cold resistant covering conditions. The results showed that during the natural cooling process, overwintering survival rate, soluble sugar and soluble protein content in leaves were ranked with C>A>B, the relative conductance of leaves was ranked with C>A>B, relative water content ranked with C>B>A. The conductance of the three types of Hydrangea increased with the decrease of temperature;there was a partial correlation between soluble sugar, soluble protein, and relative water content and temperature changes. The comprehensive evaluation results showed that almost all three types of Hydrangea could achieve outdoor overwintering in the Beijing area, but there were certain differences in cold resistance. The cold resistance was ranked with ‘Endless Summer’ ‘Annabelle’ and ‘Vanilla Strawberry’. The use of covering could have a certain cold resistance effect. [ABSTRACT FROM AUTHOR]

It has been established that the variation in the conductance of insulation made with materials of various chemical nature and physical structure (polyvinyl chloride plastic compound and varnished cambric) with a short-term exposure to a mold fungus has an S-shaped character. The unambiguous correlation of the induction period, the stage of rapid increase and the time to reach the quasi-stationary level of conductance with the induction period, the stage of rapid growth, the time to reach the maximum amount of biomass on the surface of the material is due to the sorption by isolation of the metabolic products of the mold fungus. The variation in conductance at short times of exposure to microorganisms (~ 1 month) is reversible. Removal of microorganisms from the surface leads to a decrease in conductance to its original level. With their longer exposure (~ 1 year), the change in conductance may become irreversible as a result of the biochemical decomposition of insulation components, in particular, dialkyl phthalates - polyvinyl chloride plasticizers. Features of the processes of changes in conductance are due to the duration of the growth of microorganisms, the nature of materials and their components. The growth of microorganisms depends primarily on temperature and humidity conditions. For materials with high water absorption (varnished cambric), the most important external factor is temperature, and for materials with low water absorption (polyvinyl chloride) – relative humidity. [ABSTRACT FROM AUTHOR]

Ferroelectric charged domain walls offer a revolutionary path for next-generation ferroelectric devices due to their exceptional conductivity within an otherwise insulating matrix. However, quantitative understanding of this "giant conductivity" has remained elusive due to the lack of robust models describing carrier behavior within CDWs. The current paper bridges this critical knowledge gap by employing a first-principles approach that incorporates Boltzmann transport theory and the relaxation time approximation. This strategy enables the calculation of carrier concentration, mobility, and conductivity for both head-to-head and tail-to-tail domain wall configurations within a stabilized periodic structure. The comprehensive transport analysis given here reveals that the accumulation of charge carriers, particularly their concentration, is the dominant factor governing domain wall conductance. Interestingly, observed conductance differences between head-to-head and tail-to-tail walls primarily arise from variations in carrier mobility. Additionally, this study demonstrates a significantly reduced domain wall width compared to previous reports. This miniaturization is attributed to the presence of compressive strain, which lowers the energy barrier for electron–hole pair generation. Furthermore, the findings here suggest that reducing the band gap presents a viable strategy for stabilizing charged domain walls. These results pave the way for the optimization and development of domain wall devices across a spectrum of ferroelectric materials. [ABSTRACT FROM AUTHOR]

Sea level rise (SLR) is a crucial indicator of climate change, primarily driven by greenhouse gas emissions and the subsequent increase in global temperatures. The impact of SLR, however, varies regionally due to factors such as ocean bathymetry, resulting in distinct shifts across different areas compared to the global average. Understanding the complex factors influencing SLR across diverse spatial scales, along with the associated uncertainties, is essential. This study focuses on the East Coast of the United States and Gulf of Mexico, utilizing historical SLR data from 1993 to 2023. To forecast SLR trends from 2024 to 2103, a weighted ensemble model comprising SARIMAX, LSTM, and exponential smoothing models was employed. Additionally, using historical greenhouse gas data, an ensemble of LSTM models was used to predict real-time SLR values, achieving a testing loss of 0.005. Furthermore, conductance and dissolved oxygen (DO) values were assessed for the entire forecasting period, leveraging forecasted SLR trends to evaluate the impacts on marine life, agriculture, and infrastructure. [ABSTRACT FROM AUTHOR]

Manipulation of the electronic properties of layered transition-metal dichalcogenides (TMDs) is of fundamental significance for a wide range of electronic and optoelectronic applications. Surface charge transfer doping is considered to be a powerful technique to regulate the carrier density of TMDs. Herein, the controllable p-type surface modification of few-layer WSe2 by FeCl3 Lewis acid with different doping concentrations have been achieved. Effective hole doping of WSe2 has been demonstrated using Raman spectra and XPS. Transport properties indicated the p-type FeCl3 surface functionalization significantly increased the hole concentration with 1.2 × 1013 cm−2, resulting in 6 orders of magnitude improvement for the conductance of FeCl3-modified WSe2 compared with pristine WSe2. This work provides a promising approach and facilitate the further advancement of TMDs in electronic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] The structural details of foams made with pea albumins are affected by the pH of the initial solution and followed heat treatment. An in situ, time-resolved investigation of foams prepared with pea albumins was conducted using small-angle neutron scattering (SANS) in combination with imaging and conductance measurements. Solutions were tested at pH three pH values (3, 4.5, and 8) before and after heating (90 °C for 1 and 5 min). The characteristic structures present in the foam from the nano to the meso-scale differed during drainage depending on solution pH. Foams obtained at pH 3, had the largest bubble radius and thinnest plateau border, as well as the highest extent of liquid drainage. At pH 4.5, close to the isoelectric point of the proteins, foams displayed similar bubbles' behavior to those at pH 8, but with the largest film thickness. In this case, the proteins were extensively aggregated. Heating of the solutions prior to foaming did not significantly affect the foam aging regardless of pH. The quantification of specific surface areas and film thickness over time without sample disruption shows to be a powerful approach to designing foam structures. [ABSTRACT FROM AUTHOR]

Ferroelectric charged domain walls offer a revolutionary path for next-generation ferroelectric devices due to their exceptional conductivity within an otherwise insulating matrix. However, quantitative understanding of this “giant conductivity” has remained elusive due to the lack of robust models describing carrier behavior within CDWs. The current paper bridges this critical knowledge gap by employing a first-principles approach that incorporates Boltzmann transport theory and the relaxation time approximation. This strategy enables the calculation of carrier concentration, mobility, and conductivity for both head-to-head and tail-to-tail domain wall configurations within a stabilized periodic structure. The comprehensive transport analysis given here reveals that the accumulation of charge carriers, particularly their concentration, is the dominant factor governing domain wall conductance. Interestingly, observed conductance differences between head-to-head and tail-to-tail walls primarily arise from variations in carrier mobility. Additionally, this study demonstrates a significantly reduced domain wall width compared to previous reports. This miniaturization is attributed to the presence of compressive strain, which lowers the energy barrier for electron–hole pair generation. Furthermore, the findings here suggest that reducing the band gap presents a viable strategy for stabilizing charged domain walls. These results pave the way for the optimization and development of domain wall devices across a spectrum of ferroelectric materials.

Sea level rise (SLR) is a crucial indicator of climate change, primarily driven by greenhouse gas emissions and the subsequent increase in global temperatures. The impact of SLR, however, varies regionally due to factors such as ocean bathymetry, resulting in distinct shifts across different areas compared to the global average. Understanding the complex factors influencing SLR across diverse spatial scales, along with the associated uncertainties, is essential. This study focuses on the East Coast of the United States and Gulf of Mexico, utilizing historical SLR data from 1993 to 2023. To forecast SLR trends from 2024 to 2103, a weighted ensemble model comprising SARIMAX, LSTM, and exponential smoothing models was employed. Additionally, using historical greenhouse gas data, an ensemble of LSTM models was used to predict real-time SLR values, achieving a testing loss of 0.005. Furthermore, conductance and dissolved oxygen (DO) values were assessed for the entire forecasting period, leveraging forecasted SLR trends to evaluate the impacts on marine life, agriculture, and infrastructure.

Two-pore channels are pathophysiologically important Na+-and Ca2+-permeable channels expressed in lysosomes and other acidic organelles. Unlike most other ion channels, their permeability is malleable and ligand-tuned such that when gated by the signaling lipid PI(3,5)P2, they are more Na+-selective than when gated by the Ca2+ mobilizing messenger nicotinic acid adenine dinucleotide phosphate. However, the structural basis that underlies such plasticity and single-channel behavior more generally remains poorly understood. A recent Cryo-electron microscopy (cryo-EM) structure of TPC2 bound to PI(3,5)P2 in a proposed open-channel conformation provided an opportunity to address this via molecular dynamics (MD) simulation. To our surprise, simulations designed to compute conductance through this structure revealed almost no Na+ permeation events even at very high transmembrane voltages. However further MD simulations identified a spontaneous transition to a dramatically different conformation of the selectivity filter that involved expansion and a flip in the orientation of two core asparagine residues. This alternative filter conformation was remarkably stable and allowed Na+ to flow through the channel leading to a conductance estimate that was in very good agreement with direct single-channel measurements. Furthermore, this conformation was more permeable for Na+ over Ca2+. Our results have important ramifications not just for understanding the control of ion selectivity in TPC2 channels but also more broadly in terms of how ion channels discriminate ions. [ABSTRACT FROM AUTHOR]

Let (K,d) be a connected compact metric space and p\in (1, \infty). Under the assumption of Kigami [ Conductive homogeneity of compact metric spaces and construction of p-energy , Memoirs of the European Mathematical Society, vol. 5, Europea Mathematical Society (EMS), Berline, 2023, Assumption 2.15] and the conductive p-homogeneity, we show that \mathcal {W}^p(K)\subset C(K) holds if and only if p>\operatorname {dim}_{AR}(K,d), where \mathcal {W}^p(K) is Kigami's (1,p)-Sobolev space and \operatorname {dim}_{AR}(K,d) is the Ahlfors regular dimension. [ABSTRACT FROM AUTHOR]

In the era of technology development, the optimization of production processes, quality control and at the same time increasing production efficiency without wasting food, artificial intelligence is becoming an alternative tool supporting many decision-making processes. The work used modern machine learning and physical analysis tools to evaluate food products (pectins). Various predictive models have been presented to estimate the viscosity of pectin. Based on the physical analyses, the characteristics of the food product were isolated, including L*a*b* color, concentration, conductance and pH. Prediction was determined using the determination index and loss function for individual machine learning algorithms. As a result of the work, it turned out that the most effective estimation of pectin viscosity was using Decision Tree (R2 = 0.999) and Random Forest (R2 = 0.998). In the future, the prediction of pectin properties in terms of viscosity recognition may be significantly perceived, especially in the food and pharmaceutical industries. Predicting the natural pectin substrate may contribute to improving quality, increasing efficiency and at the same time reducing losses of the obtained final product. [ABSTRACT FROM AUTHOR]

The maximum power point tracking (MPPT) algorithms are required to deliver the optimal energy from solar photovoltaic cells/array (PV) under numerous weather conditions. Therefore, MPPT circuits driven by defined rules called algorithms are designed. These algorithms range from simple to complex in design and implementation and are selected based on the scenarios of the surroundings. However, the incremental conductance (InC) MPPT algorithm is one of the market's most simple, easy to implement, and demanding algorithms. The drawback associated with the InC algorithm is its tracking speed. To overcome this weakness various researchers have made multiple improvements. Although the performance became better but was not satisfied. Further, the improvements introduce steady-state oscillations of the operating point around the MPP. So, the user needs to pick and choose based on demand. Keeping the target in focus, we have introduced a couple of modifications in the structure of INC. that remain fruitful. The proposed structure named the augmented InC algorithm has shown marvelous improvement in tracking speed and steady-state oscillations. The results have been compared with the conventional InC algorithm, where the proposed augmented InC algorithm has outperformed the conventional InC algorithm in tracking speed and steady-state oscillations. We have used the MATLAB script to code the conventional InC algorithm and proposed augmented InC algorithms based on their designed flowchart. Both algorithms have been applied to the standalone solar photovoltaic system composed of a solar photovoltaic array, DC/DC boost converter, illumination and temperature inputs, MPPT algorithm, and a DC load. The model is designed in Simulink/MATLAB. [ABSTRACT FROM AUTHOR]

Groundwater quality assessment has become vital issues all over the world as remediation of contaminated water is extremely challenging. Due to the unconfined nature of Nsukka and Igbo-Etiti groundwater and the highly intensive agricultural practices observed in these areas, assessment of groundwater vulnerability to contamination is inevitable. This study employed vertical electrical sounding (VES) in forty-two (42) different locations of Nsukka and Igbo-Etiti area with the intent to assess groundwater susceptibility to contamination using GOD, GODL and GLSI models. Results from VES delineated a total of four-to-five geoelectric layers. From VES result on the layer's geologic unit's constrained with the borehole log information on geologic unit serving as water-bearing unit in the area, the fourth layer was delineated as the aquifer layer in most locations of the study area within fine-to-medium coarse-grained sand. Results of groundwater vulnerability assessment as established using GODindex classified the aquifer units in the study area as low vulnerable units. GODLindex and GLSI models establishing different range of vulnerability index classified the areas aquifer units into high, moderate and low vulnerable zones. Results of single parameter and map removal sensitivity analysis on GOD and GODL model delineated overlying lithology and longitudinal conductance, respectively, as the most sensitive parameters in vulnerability assessment of the study area. Aquifer vulnerability potential zone maps generated revealed the vulnerability class distributions. These results will assist in sensitizing the habitants against indiscriminate disposal of waste and also guide the government in effective monitoring and management of groundwater repositories. [ABSTRACT FROM AUTHOR]

The influence of a a rectangular potential barrier on the quantum transport of fermions in silicene is explored. Specifically, analytical solutions are presented to derive transmission and reflection probabilities together with conductance. It is shown that the transmission is highly sensitive to both the barrier height and incident energy. As a result, the occurrence of Klein and resonant tunnelings is observed, with a significant dependence on the barrier width. Notably, it is found that perfect transmission extends beyond normal incidence, occurring at various oblique angles. Moreover, the transmission pattern exhibits a more fragmented structure with increasing barrier width, reminiscent of Fabry‐Pérot resonances. In contrast, the conductance displays a non‐monotonic dependence on incident energy and features rapid oscillations with a rising barrier height. However, at a constant barrier height, there is a minimal disparity among conductance profiles for high incident energy values. When incident energy equals the barrier height, the conductance experiences a local minimum. For a thin barrier, a substantial reduction in conductance is observed, unlike the oscillatory behavior seen with a thicker barrier. These findings underscore the progress in silicene research and offer a fresh perspective on the relativistic applications of tunneling in this material. [ABSTRACT FROM AUTHOR]

Abstract The objective of this work was to evaluate the influence of herbicides 2,4-D and dicamba on the physiological response of chlorophyll a in olive (Olea europaea) seedlings. The following eight rates of the 2,4 D (670 g a.e. ha-1) and dicamba (720 g a.e. ha-1) herbicides were applied: 0, 1.56, 3.13, 6.25, 12, 25, 50, and 100% of the recommended for burndown. The herbicides were applied at 80 cm above the seedlings using a CO2 pressurized back sprayer with a 150 L ha-1 spray volume. Plant gas exchange was measured using a portable infrared gas analyzer. Chlorophyll a fluorescence was evaluated using a portable modulated light fluorometer. The application of both herbicides caused a decrease in the process of CO2 assimilation in the plants, reducing net photosynthesis and stomatal conductance. The 2,4-D herbicide caused the most severe effects on the variables related to chlorophyll a fluorescence. Low values of maximum quantic yield were observed after the application of the herbicides, of which dicamba was the most harmful. Both herbicides damage the photosynthetic apparatus of olive seedlings.

Leaf gas-exchange measurements are useful in assessing plant environmental responses. However, uncertainties in the leaf gas-exchange model potentially limit its application. The main challenge in the model-dependent calculations is to detect violations of assumptions. Here, we developed a system that integrates into one instrument the direct measurement of leaf intercellular CO2 concentration and the standard open-flow (OF) and novel open-diffusion (OD) systems for flux measurement. In the OD system, a gas-permeable membrane between the leaf ambient air and outside air creates CO2 and H2O differentials, rather than the air flow in the OF chamber. We measured hypostomatous and amphistomatous leaves of several species with different photosynthetic capacities [sunflower (Helianthus annuus), grape (Vitis vinifera), lemon (Citrus limon), and cherry (Prunus avium)]. The CO2 and H2O differentials in the OD system strictly depend on the flux measured by the OF system. The lower permeability of the membrane resulted in a larger differential per flux, indicating that the OD system can increase the resolution for a small flux. An analysis of the conductance model along with observations suggested that cuticle and leaf intercellular conductances and the unsaturation of leaf humidity contributed to discrepancies between the direct measurement and standard calculation. The combined system developed here provides an opportunity to address these overlooked concepts in leaf gas exchange. [ABSTRACT FROM AUTHOR]

There are currently few methods available to measure the conductance of water vapor through an orifice. The feasibility of the pressure rising method to measure the conductance of water vapor is analyzed by combining theory with experiment, indicating that the measurement error of this method increases with the decrease of intake volume, which is due to the strong adsorption characteristic of water vapor. To accurately obtain the relationship between the conductance of water vapor and the inlet pressure, a new method called the time-ratio method is proposed. This method calculates conductance by measuring the time of pressure change, reducing the effect of water vapor adsorption on the measurement effectively. Based on this method, a device is developed to provide a flow rate in the range of 3. 7×10-9 ~1. 5×10-5 Pa·m³· s-1. The measurement and theoretical values of conductance have good consistency, and the relative standard uncertainty of this time‑ratio method is 3. 3%. [ABSTRACT FROM AUTHOR]

We study the transport properties of Dirac fermions in ABC trilayer graphene (ABC-TLG) superlattices. More specifically, we analyze the impact of varying the physical parameters-the number of cells, barrier/well width, and barrier heights-on electron tunneling in the ABC-TLG. In the initial stage, we solved the eigenvalue equation to determine the energy spectrum solutions for the ABC-TLG superlattices. Subsequently, we applied boundary conditions to the eigenspinors and employed the transfer matrix method to calculate transmission probabilities and conductance. For the two-band model, we identified the presence of Klein tunneling, with a notable decrease as the number of cells increased. The introduction of interlayer bias opened a gap as the number of cells increased, accompanied by an asymmetry in scattered transmission. Increasing the barrier/well width and the number of cells resulted in an amplified number of gaps and oscillations in both two-band and six-band cases. We observed a corresponding decrease in conductance as the number of cells increased, coinciding with the occurrence of a gap region. Our study demonstrates that manipulating parameters such as the number of cells, the width of the barrier/well, and the barrier heights provides a means of controlling electron tunneling and the occurrence of gaps in ABC-TLG. Specifically, the interplay between interlayer bias and the number of cells is identified as a crucial factor influencing gap formation and transmission asymmetry. [ABSTRACT FROM AUTHOR]

We report the preparation of polyaniline (PANI) covered La2O3 binary composite material using in situ oxidativepolymerization method using APS as oxidant in acidic medium. Prepared material was characterized using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) to understand the structure and bonding. Transmission electron microscopy (TEM) estimated the particle size confirming the synthesis of particles in nanorange. For chemical composition and thermal stability, energy dispersive X-ray and thermogravimetric (TG) analysis respectively were performed. Cyclic voltametric measurement of PANI-La2O3 nanocomposite having a semi-rectangular loop of high area exhibited high specific conductance (Csp = 373 Fg-1). The high ionic and electrical conductivity alongwith high charge storage capability makes PANI-La2O3 nanocomposite a potential candidate for its usage as electrode material in supercapacitor. [ABSTRACT FROM AUTHOR]

In the Fastest Mixing Markov Chain problem, we are given a graph G = (V , E) and desire the discrete-time Markov chain with smallest mixing time τ subject to having equilibrium distribution uniform on V and non-zero transition probabilities only across edges of the graph. It is well-known that the mixing time τ RW of the lazy random walk on G is characterised by the edge conductance Φ of G via Cheeger's inequality: Φ - 1 ≲ τ RW ≲ Φ - 2 log | V | . Analogously, we characterise the fastest mixing time τ ⋆ via a Cheeger-type inequality but for a different geometric quantity, namely the vertex conductance Ψ of G: Ψ - 1 ≲ τ ⋆ ≲ Ψ - 2 (log | V |) 2 . This characterisation forbids fast mixing for graphs with small vertex conductance. To bypass this fundamental barrier, we consider Markov chains on G with equilibrium distribution which need not be uniform, but rather only ε -close to uniform in total variation. We show that it is always possible to construct such a chain with mixing time τ ≲ ε - 1 (diam G) 2 log | V | . Finally, we discuss analogous questions for continuous-time and time-inhomogeneous chains. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) tungsten selenide (WSe2) is promising candidate material for future electronic applications, owing to its potential for ultimate device scaling. For improving the electronic performance of WSe2-based field-effect transistors (FETs), the modification of surface properties is essential. In this study, the seamless structural phase transition in WSe2 lattice is achieved by soft oxygen plasma, regulating the electrical conductance of WSe2-based FETs. We found that during the soft oxygen plasma treatment with optimal processing time, the generated oxygen ions can substitute some selenium atoms and thus locally modify the bond length, inducing 2H → 1T phase transition in WSe2 with seamless interfaces. The mosaic structures have been proven to tailor the electronic structure and increase the hole carrier concentration inside WSe2, significantly increasing the channel conductance of WSe2 FETs. With the further increase of the oxygen plasma treatment time, the creation of more selenium vacancy defects leads to the electronic doping, resulting in the reduction of conductance. Benefiting from the hexagonal boron nitride (h-BN) encapsulation to interrupt the partial structural relaxation from 1T to 2H phase, our WSe2 FET exhibits high electronic stability with conductance of 6.8 × 10−4 S, which is about four orders of magnitude higher than 2H WSe2 (5.8 × 10−8 S). This study could further broaden the WSe2 FETs in applications for functionalization and integration in electronics. [ABSTRACT FROM AUTHOR]

Featured Application: The radiative thermal memristor boasts versatile applications, excelling particularly in contactless thermal sensing, where its unique properties make it ideal for scenarios requiring non-intrusive temperature measurements. Additionally, it holds promise in revolutionizing neuromorphic computing systems, contributing significantly to energy-efficient information processing that mimics the human brain. Furthermore, the integration of radiative thermal memristors into memory devices presents opportunities for optimizing performance, enhancing data storage, and advancing memory device technologies. This study presents a theoretical framework for a radiative thermal memristor (RTM), utilizing Tungsten-doped vanadium dioxide (WVO) as the phase-change material (PCM) and silicon carbide (SiC) in the far-field regime. The behavior of the RTM is depicted through a Lissajous curve, illustrating the relationship between net flux (Q) and a periodically modulated temperature difference Δ T(t). It is established that temperature variations in the memristance (M) of the RTM form a closed loop, governed by PCM hysteresis. The analysis explores the impact of thermal conductivity contrast (r) and periodic thermal input amplitude (θ) on the Q– Δ T curve and the M– Δ T curve and negative differential thermal resistance (NDTR), revealing notable effects on the curve shapes and the emergence of NDTR. An increasing r leads to changes in the Lissajous curve's shape and enhances the NDTR influence, while variations in both r and (θ) significantly affect the Q values and Lissajous curve amplitudes. In the M– Δ T curve, the height is linked to thermal conductivity contrast (r), with increasing r resulting in higher curve heights. [ABSTRACT FROM AUTHOR]

When a shutter, which differentiates between two adjacent particles' reservoirs with a voltage gap, is lifted, a current emerges. In this paper, the temporal dynamics of this emerging current is analyzed. The main results are as follows: (A) the current's prefactor in the short-time behavior is related to the long-time frequencies, by which the current converges to its equilibrium value (the conductance quantum unit 2e2/h). (B) In the short-time regime, the current is proportional to the square root of the time. (C) The maximum overshoot conductance is bounded by Gmax = ζe2/h, where ζ is a universal value which is very close to Euler's number. (D) Most of these results are valid for a thin wire in 3D, even in the presence of electron–electron interactions. [ABSTRACT FROM AUTHOR]

We present the first large‐scale statistical survey of the Jovian main emission (ME) to map auroral properties from their ionospheric locations out into the equatorial plane of the magnetosphere, where they are compared directly to in‐situ spacecraft measurements. We use magnetosphere‐ionosphere (MI) coupling theory to calculate currents from the auroral brightness as measured with the Hubble Space Telescope and from plasma flow speeds measured in‐situ with the Galileo spacecraft. The effective Pedersen conductance of the ionosphere ΣP∗ $\left({{\Sigma }}_{P}^{\ast }\right)$ remains a free parameter in this comparison. We calculate the Pedersen conductance from the combined data sets, and find it ranges from 0.03<ΣP∗<2.40 $0.03< {{\Sigma }}_{P}^{\ast }< 2.40$ mho overall with averages of 0.13−0.07+0.26 $0.1{3}_{-0.07}^{+0.26}$ mho in the north and 0.16−0.10+0.34 $0.1{6}_{-0.10}^{+0.34}$ mho in the south. Considering the HST‐derived field‐aligned currents per radian of azimuth only, we find values of I‖=9.34−3.54+5.72 ${I}_{\Vert }=9.3{4}_{-3.54}^{+5.72}$ MA rad−1 and I‖=8.61−3.05+6.77 ${I}_{\Vert }=8.6{1}_{-3.05}^{+6.77}$ MA rad−1 in the north and south, respectively, in general agreement with previous results. Taking the currents and effective Pedersen conductance together, we find that the average ME intensity and plasma flow speed in the middle magnetosphere (10–30 RJ) are broadly consistent with one another under MI coupling theory. We find evidence for peaks in the distribution of ΣP∗ ${{\Sigma }}_{P}^{\ast }$ near dawn, then again near 12 and 14 hr magnetic local time (MLT). This variation in Pedersen conductance with MLT may indicate the importance of conductance in modulating MLT‐ and local‐time‐asymmetries in the ME, including the apparent subcorotation of some auroral features within the ME. Plain Language Summary: The brightest part of Jupiter's aurorae– the main emission– forms arcs of sheet‐like lights surrounding both magnetic poles, similar to the Earth's aurorae. At both planets, these lights are caused by charged particles flowing into the planet's atmosphere, where they collide with gases and glow. According to one theory, at Jupiter these particles are electrons which flow in electrical currents connecting the planet to the charged‐particle‐filled space surrounding it. Here, we use Hubble Space Telescope images of Jupiter's aurorae spanning a decade to build up an average picture of the brightness and location of this main emission. The brightness is related to the energy of the electrons, which in turn is related to the strength of the electrical currents. We then use particle measurements made by the Galileo spacecraft in orbit around Jupiter to make an average picture of these particles as they move around Jupiter. These speeds are related to the same electrical currents, but include an electrical conductivity term describing how easily currents flow through Jupiter's auroral atmosphere. We combine all these measurements to calculate the conductivity, and present results which are consistent with expectations but which fluctuate more quickly than expected in parts of the main emission. Key Points: The effective ionospheric Pedersen conductance in Jupiter's main emission auroral region is derived from remote and in‐situ measurementsEffective Pedersen conductances of ∼0.14 mho and field‐aligned auroral currents near ∼10 MA/rad−1 are derived, consistent with past workThe effective Pedersen conductance varies significantly in magnetic local time, and may explain the enigmatic motions of some auroral forms [ABSTRACT FROM AUTHOR]

Average-value models (AVMs) of voltage-source converters (VSCs) are widely used as numerically efficient alternatives to their discrete switching models in electromagnetic transient (EMT) simulations. Recently, a so-called directly-interfaced AVM (DI-AVM) has been developed for VSCs, permitting large simulation time steps favorable for system-level offline and/or real-time studies. Although enabling large step sizes, the conductance/resistance matrix of the DI-AVM is time-varying and needs to be calculated at every simulation time step, which requires additional computational resources. This paper proposes a constant-parameter DI-AVM (CP-DI-AVM) for more efficient simulations of VSC-based power-electronic systems that does not require re-calculation of the network conductance matrix in EMT simulators. This is achieved by using a numerical approximation that only slightly reduces the solution accuracy. The performance of the proposed CP-DI-AVM is demonstrated on a large-scale VSC-based energy conversion system implemented in PSCAD/EMTDC. The proposed CP-DI-AVM is shown to have numerical advantages over the prior DI-AVM and the conventional AVMs of VSCs.

Periodic nanostructure is a novel method to manipulate the electronic properties in electronics. An efficient method in this paper is proposed to judge whether m identical periods' magnetic nanostructure is a periodic structure by judging whether its physical structure and its magnetic vector potential structure both keep periodic. By investigating the influence of the δ -doping potential on the electron transport properties with m identical periods' magnetic barrier nanostructure of InAs system, it shows that, firstly, the resonant peak of transmission probability, conductance, and spin polarization has been induced by splitting into (2 m − 1) folds with m units nanostructure, respectively, especially when the resonant peak of transmission probability is almost close to 1 as the incident energy is lower; secondly, the height of δ -doping potential has an extensive influence on the resonant peak of transmission probability, which the resonant peak will be more dependent of the height of δ -doping potential increasing. Meanwhile, the conductance will be decreased with the height of δ -doping potential increasing. [ABSTRACT FROM AUTHOR]

Background: The rapid delayed rectifier potassium current (IKr) is important for cardiac repolarization and is most often involved in drug-induced arrhythmias. However, accurately measuring this current can be challenging in human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes because of its small current density. Interestingly, the ion channel conducting IKr, hERG channel, is not only permeable to K+ ions but also to Cs+ ions when present in equimolar concentrations inside and outside of the cell.Methods: In this study, IhERG was measured from Chinese hamster ovary (CHO)-hERG cells and hiPSC-CM using either Cs+ or K+ as the charge carrier. Equimolar Cs+ has been used in the literature in manual patch-clamp experiments, and here, we apply this approach using automated patch-clamp systems. Four different (pre)clinical drugs were tested to compare their effects on Cs+- and K+-based currents.Results: Using equimolar Cs+ solutions gave rise to approximately ten-fold larger hERG conductances. Comparison of Cs+- and K+-mediated currents upon application of dofetilide, desipramine, moxifloxacin, or LUF7244 revealed many similarities in inhibition or activation properties of the drugs studied. Using equimolar Cs+ solutions gave rise to approximately ten-fold larger hERG conductances. In hiPSC-CM, the Cs+-based conductance is larger compared to the known K+-based conductance, and the Cs+ hERG conductance can be inhibited similarly to the K+-based conductance.Conclusion: Using equimolar Cs+ instead of K+ for IhERG measurements in an automated patch-clamp system gives rise to a new method by which, for example, quick scans can be performed on effects of drugs on hERG currents. This application is specifically relevant when such experiments are performed using cells which express small IKr current densities in combination with small membrane capacitances. [ABSTRACT FROM AUTHOR]

A comprehensive characterization of key mechanisms underlying signal transmission within the human brain remains an unsolved problem. The neuronal surface, composed principally of phosphatidylcholine (POPC), has a known ordering effect on water. This produces highly organized water layers (OWLs) at the neuron–water interface—the neurochemical implications of which are not currently understood. The human brain is 75% water by volume, with folds and grooves to maximize surface area, suggesting that characterization of neuronal OWLs may contribute to an understanding of neuronal signal transmission. Previous experimental work has measured enhanced conductivity of POPC OWLs relative to bulk water. The mechanism underlying this conductivity is still debated. Using quantum chemical methods on a POPC–water interface model system, we present data characterizing OWL conductance. Non-equilibrium Green's function calculation results demonstrate that there is negligible electron transfer-based conductivity through the OWL at biological temperatures. This is consistent with existing studies suggesting the Grotthuss mechanism as the most likely explanation for experimentally observed enhanced conductivity at the POPC–water interface. The broader implications of enhanced proton conductivity at the neuron–water interface are discussed. [ABSTRACT FROM AUTHOR]

One function of plant Si is ameliorating stress, including drought and salinity stress, which can induce active Si uptake in addition to passive uptake via transpiration. However, the interactions and feedbacks between stress, water movement and Si uptake remain unknown.To examine this gap, we compiled papers reporting transpiration and/or stomatal conductance of plants exposed to stresses while varying Si availability.Our meta‐analysis (34 studies, excluding rice) showed that stress alters the role of Si in controlling water movement across diverse plant groups. Increased Si availability significantly increased water movement in stressed plants, particularly stomatal conductance (p < 0.001, k = 84) in plants exposed to salinity (p < 0.05, k = 20) and drought (p < 0.05, k = 45) stress.This signal of increased conductance was most apparent in C4 plants (p < 0.001, k = 41) and Poales (p < 0.001, k = 47). These findings have implications for plants under increasing water and salinity stress, particularly for Poales, where survival in affected ecosystems could be mediated by soil Si availability, and in agricultural systems, supplying Si to water‐stressed plants could increase productivity.Intriguingly, Si addition to unstressed plants had no consistent impact on water movement, with reduction of water movement with Si addition to unstressed plants in 50% of studies, mostly those involving non‐Poales species. This is an important first broad‐scale Si cost quantification, as the costs of Si for plants have remained stubbornly mysterious, hampering evolutionary and functional understanding of plant Si use. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The conductance and electronic transmission of Dirac electrons and holes across multibarrier Cantor-like graphene are investigated using on the transfer matrix method and Landauer–Buttiker formalism. Electric and magnetic fields are applied to the top of a monolayer graphene to generate multiple electromagnetic barriers separated by quantum wells. The impact of the magnetic and electric fields as well as the quantum size on the behavior of the transmission coefficient and conductance is discussed. The results indicate that the transmission coefficients exhibit oscillations indicating the existence of resonant states in miniband energies separated by minigap energies. This phenomenon known as the bifurcation process is more pronounced for a higher number of barriers. The behavior observed in the conductance variation reflects of the transmission coefficient especially for lower energies. Furthermore, the contour plot of the transmission coefficient shows the predominant impact of the incidence angle on the symmetry of the minigaps and minibands. These results are expected to be beneficial for experiments that improve the performance of new generations of devices based on multibarrier Cantor-like graphene systems. [ABSTRACT FROM AUTHOR]

Wet oxidation has been undergone at dissimilar temperatures from 400 until 1000 °C for deposition of high dielectric constant ternary hafnium tantalum oxide films on silicon (Si) substrates. Amorphous to polycrystalline phase transformation happened as a function of temperature. An increase in the oxygen vacancy formation was observed and the calculated k values ranged from 16.5 to 31.1. However, interfacial layer formation happened exaggeratedly at 1000 °C, which could be associated with the reduction in nitrogen accumulation at the interface between the oxide and Si at this temperature, and thus resulting in the lowest total interface trap density (D total). Conductance-voltage measurement showed the location of interface states that were closer to conduction band of the oxide. The findings were in coordination with structural, morphological, and optical characteristics of the samples. A simple mechanism illustrating formation of the ternary film was also proposed. [ABSTRACT FROM AUTHOR]

We investigate the spin-dependent spin-polarization and transport properties in altermagnet-based resonant tunneling junctions, in which the altermagnet has two symmetric orientations of spin-split Fermi surface. In the first model the Fermi surface is an ellipse with the major axes either parallel or perpendicular to the altermagnet/barrier interface, and the Fermi surface in the second one is also an ellipse but the major and the minor axes have the same angle relative to the altermagnet/barrier interface. Our findings reveal that the transport properties for spin-up and spin-down electrons are spin polarized and depend on the orientation of the altermagnet with respect to the interface. In contrast to conventional ferromagnetic and antiferromagnetic splitting mechanisms, the transmission in our study exhibits spin splitting with an alternating sign. For the first model, the total spin-polarization is zero, indicating a lack of net magnetization due to the combined effects of spin and real-space symmetries, thereby reflecting normal metal properties. Conversely, in the second model, a discernible total spin-polarization emerges, indicative of ferromagnetism. These orientation-dependent transport properties exemplify the unique features of the altermagnetism. The anisotropic altermagnetic state in momentum space can be measured by the orientation-dependent conductance in these resonant tunneling junctions.

This study aimed to characterize the physiological and structural responses of potted one-year-old olive trees belonging to two olive cultivars—‘Nocellara del Belice’ and ‘Cerasuola’—exposed to prolonged drought under greenhouse conditions. Two irrigation treatments based on evapotranspiration (ET) were imposed for 69 days, i.e., well-watered (WW, 100% ET) and drought-stressed (DS, 10−30% ET). Leaf stomatal conductance (gs), stem water potential (Ψstem), transpiration (E), photosynthetic capacity (Amax), water use efficiency (WUE), stem (Kstem) and root (Kroot) hydraulic conductance, trunk diameter variations (TDV), and leaf patch attenuated pressure fluctuations (pp, a proxy of the inverse of leaf turgor pressure) were measured in WW and DS trees at different stages of the experiment. Leaf gs did not significantly differ between cultivars under DS, whereas differences in Ψstem only became significant at the end of prolonged drought, when ‘Nocellara del Belice’ experienced Ψstem < −4 MPa. ‘Cerasuola’ trees expressed the best WUE under drought, although they were more susceptible to photoinhibition under optimal plant water status. Both cultivars tended to increase their Kstem at the end of the drought period. A marked reduction in Kroot occurred in ‘Cerasuola’ plants after prolonged drought; however, a similar mechanism was not observed in ‘Nocellara del Belice’. The ratio between Kstem and Kroot exponentially increased towards the end of the prolonged drought period in both cultivars, but more markedly in ‘Cerasuola’. TDV and pp trends suggested that ‘Cerasuola’ plants keep better plant water status under severe drought compared to ‘Nocellara del Belice’ by maintaining high leaf turgor and reduced trunk diameter fluctuations. These responses may be related to reduced cell wall elasticity and xylem vessel size and/or wall thickness—drought avoidance mechanisms. The Kstem/Kroot ratio can serve as an indicator of drought stress avoidance mechanisms to compare genotype-specific responses to drought stress.

The article titled "Aharonov–Bohm Flux Effects on the Landauer Conductance in Graphene Wormhole" discusses corrections to equations and figures in the original publication. The corrected equations are provided, and the necessary revisions to the text are explained. The authors clarify that the miscalculation does not affect the other results and conclusions presented in the article. The article is authored by Jonathan Acuña Huamaní, Andrés G. Jirón Vicente, Angel E. Obispo, Raul Carita Montero, and Luis B. Castro. [Extracted from the article]

In this study, it was aimed to produce an organic interface layered Schottky diode structure and frequency effect on capacitance-conductance-voltage measurements. In this context, phosphor doped n-type Si single crystal has been used as a semiconductor substrate with a 1-20 Ω.cm resistivity, (100) surface oriention, 2 inches in diameter and 350 μm thickness. The (E)-5,5-difluoro-1,3,7,9-tetramethyl-10-phenyl-2-(2-(pyridin-2-yl)vinyl)-5H-54,64-dipyrrolo [1,2-c:2',1'-f] [1,3,2] diazaborinine (BODIPY-Pyridine) thin film was coated on n-Si using the spin coating technique. Ohmic and rectifier contacts were coated by evaporation of indium (In) and gold (Au) using a thermal evaporation system and Au/ BODIPY-Pyridine/n-Si/In Schottky diode was fabricated. Capacitance-voltage (C-V) and conductance-voltage (G-V) measurements of this structure were gained at different frequencies in the dark. Contingent on the frequency, the series resistance (Rs) and the interface state density (Nss) values were identified by using the conductance and Hill-Coleman method, respectively.

Background: The rapid delayed rectifier potassium current (IKr) is important for cardiac repolarization and is most often involved in drug-induced arrhythmias. However, accurately measuring this current can be challenging in human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes because of its small current density. Interestingly, the ion channel conducting IKr, hERG channel, is not only permeable to K+ ions but also to Cs+ ions when present in equimolar concentrations inside and outside of the cell.Methods: In this study, IhERG was measured from Chinese hamster ovary (CHO)-hERG cells and hiPSC-CM using either Cs+ or K+ as the charge carrier. Equimolar Cs+ has been used in the literature in manual patch-clamp experiments, and here, we apply this approach using automated patch-clamp systems. Four different (pre)clinical drugs were tested to compare their effects on Cs+- and K+-based currents.Results: Using equimolar Cs+ solutions gave rise to approximately ten-fold larger hERG conductances. Comparison of Cs+- and K+-mediated currents upon application of dofetilide, desipramine, moxifloxacin, or LUF7244 revealed many similarities in inhibition or activation properties of the drugs studied. Using equimolar Cs+ solutions gave rise to approximately ten-fold larger hERG conductances. In hiPSC-CM, the Cs+-based conductance is larger compared to the known K+-based conductance, and the Cs+ hERG conductance can be inhibited similarly to the K+-based conductance.Conclusion: Using equimolar Cs+ instead of K+ for IhERG measurements in an automated patch-clamp system gives rise to a new method by which, for example, quick scans can be performed on effects of drugs on hERG currents. This application is specifically relevant when such experiments are performed using cells which express small IKr current densities in combination with small membrane capacitances.

The article presents the results of transient electromagnetic (TEM) prospecting surveys using an unmanned aerial system carried out at Lake Baikal, which is a unique geoelectrical setting where low-resistivity lacustrine sediments are located under a relatively isotropic water body. The task was to investigate the possibility of using a drone-based TEM survey to delineate the electrical stratigraphy of the subsurface at depths between 50 and 300 m, separated into layers and blocks. A new version of the SibGIS UAV-TEM unmanned system was used, significantly improved compared to the prototype previously described in the literature. The current switch providing bipolar current pulses connected to a grounded electrical line was the source of the electromagnetic field in the geological environment. The hexacopter carrying a measuring system consisting of 18-bit ADC and sensor—analog of 50 × 50 loop, was the receiving system. We measured survey data of 16 traverses over the Baikal going from the shore to the depths. Significant attention is being paid to a new approach to data inversion. For fast interpretation of the TEM data, we used the Sτ-method, which allows for tracing the change in the apparent longitudinal conductivity with depth. It is shown that thanks to the new sensor and current switch, the data quality has increased significantly; now, the UAV system can register sounding curves up to 1 ms. As a result, new data on the geological structure of the shelf zone of Lake Baikal were obtained. They had a good fundamental agreement with the predecessor data obtained from terrestrial measurements (from ice cover), allowing us to conclude that the UAV-TEM technology can already replace conventional ground-based electromagnetic surveys. [ABSTRACT FROM AUTHOR]

In this paper, two methods Adomian Decomposition Method (ADM) and Laplace Adomian Decomposition Method (LADM) were adopted to solve the telegraph equation. The essence of this research is to establish a relationship between the two analytical methods. It was observed that the two methods were consistent as the results obtained from the numerical examples on the two methods were the same. We also generated the telegraph equation to help provide a solid basis for the application of the telegraph equation. The telegraph equation is one of the nonlinear partial differential equation and it’s application to solving practical problems were suggested for further studies. [ABSTRACT FROM AUTHOR]

The electric and dielectric processes of AlGaN/GaN/Si HEMTs produced by molecular beam epitaxy were examined utilizing direct current-voltage, impedance spectroscopy, and DLTS measurements. Using current-voltage measurements, the DC electrical characteristics of AlGaN/GaN/Si HEMTs revealed the self-heating effect. The relaxation dynamics of charge carriers appear to be studied by the conductance mechanism and electric modulus formalisms. Behavior that is frequency dependent has been observed in impedance spectroscopy. Last but not least, DLTS data have demonstrated the existence of electron traps. The prevalence of parasitic effects and conduction mechanisms are remarkably correlated with deep levels. [ABSTRACT FROM AUTHOR]

This work focuses on simulating the thermal history of a vertical wall consisting of a thermoplastic composite material, poly(ethylene terephthalate) glycol (PETG) with short carbon fiber reinforcement, manufactured using a Big Area Additive Manufacturing (BAAM) system. The incremental deposition process used in additive manufacturing, which corresponds to the repeated deposition of hot material onto cooler material, contributes to the presence of residual stresses and part warping. The prediction of these mechanisms is dependent on thermal history of the part, and the major motivation of this work was to improve the accuracy of finite element (FE) models used to quantify the thermal history of large-format additively manufactured parts. Thermocouples were placed throughout the part at varying heights to measure temperature as a function of time. The FE model developed found a thermal contact conductance between the printed part and the bed of 10 W/m2K and convection coefficient values that linearly varied from 3 to 15 W/m2K through the wall height when making a temperature comparison with the output from the thermocouples. It is also demonstrated that the FE model with a constant convection coefficient under-predicts model temperature at the beginning of the manufacturing process when compared against the model with a variable convection coefficient. The impact of this difference was seen in the stress values, which were larger for the model with a constant convection coefficient. Finally, a correlation equation was derived which allows the findings to be generalized to other vertical structures manufactured on the BAAM. In summary, this work offers valuable insights on material characterization, real-time thermocouple placement, and FE modeling of large-format additively manufactured parts. [ABSTRACT FROM AUTHOR]

Intracellular malaria parasites activate an ion and organic solute channel on their host erythrocyte membrane to acquire a broad range of essential nutrients. This plasmodial surface anion channel (PSAC) facilitates the uptake of sugars, amino acids, purines, some vitamins, and organic cations, but remarkably, it must exclude the small Na+ ion to preserve infected erythrocyte osmotic stability in plasma. Although molecular, biochemical, and structural studies have provided fundamental mechanistic insights about PSAC and advanced potent inhibitors as exciting antimalarial leads, important questions remain about how nutrients and ions are transported. Here, I review PSAC's unusual selectivity and conductance properties, which should guide future research into this important microbial ion channel. [ABSTRACT FROM AUTHOR]