Dynamic assemblies of parvalbumin interneurons in brain oscillations.

Brain oscillations are crucial for perception, memory, and behavior. Parvalbumin-expressing (PV) interneurons are critical for these oscillations, but their population dynamics remain unclear. Using voltage imaging, we simultaneously recorded membrane potentials in up to 26 PV interneurons in vivo during hippocampal ripple oscillations in mice. We found that PV cells generate ripple-frequency rhythms by forming highly dynamic cell assemblies. These assemblies exhibit rapid and significant changes from cycle to cycle, varying greatly in both size and membership. Importantly, this variability is not just random spiking failures of individual neurons. Rather, the activities of other PV cells contain significant information about whether a PV cell spikes or not in a given cycle. This coordination persists without network oscillations, and it exists in subthreshold potentials even when the cells are not spiking. Dynamic assemblies of interneurons may provide a new mechanism to modulate postsynaptic dynamics and impact cognitive functions flexibly and rapidly.

Defect Density and Atomic Defect Recognition in the Middle Layer of a Trilayer MoS2 Stack.

Molybdenum disulfide (MoS2) is one of the most intriguing two-dimensional materials, and moreover, its single atomic defects can significantly alter the properties. These defects can be both imaged and engineered using spherical and chromatic aberration-corrected high-resolution transmission electron microscopy (CC/CS-corrected HRTEM). In a few-layer stack, several atoms are vertically aligned in one atomic column. Therefore, it is challenging to determine the positions of missing atoms and the damage cross-section, particularly in the not directly accessible middle layers. In this study, we introduce a technique for extracting subtle intensity differences in CC/CS-corrected HRTEM images. By exploiting the crystal structure of the material, our method discerns chalcogen vacancies even in the middle layer of trilayer MoS2. We found that in trilayer MoS2 the middle layer's damage cross-section is about ten times lower than that in the monolayer. Our findings could be essential for the application of few-layer MoS2 in nanodevices.

Ion channel profiles of extraocular motoneurons and internuclear neurons in human abducens and trochlear nuclei.

Introduction: Extraocular muscles are innervated by two anatomically and histochemically distinct motoneuron populations: motoneurons of multiply-innervated fibers (MIF), and of singly-innervated fibers (SIF). Recently, it has been established by our research group that these motoneuron types of monkey abducens and trochlear nuclei express distinct ion channel profiles: SIF motoneurons, as well as abducens internuclear neurons (INT), express strong Kv1.1 and Kv3.1b immunoreactivity, indicating their fast-firing capacity, whereas MIF motoneurons do not. Moreover, low voltage activated cation channels, such as Cav3.1 and HCN1 showed differences between MIF and SIF motoneurons, indicating distinct post-inhibitory rebound characteristics. However, the ion channel profiles of MIF and SIF motoneurons have not been established in human brainstem tissue. Methods: Therefore, we used immunohistochemical methods with antibodies against Kv, Cav3 and HCN channels to (1) examine the human trochlear nucleus in terms of anatomical organization of MIF and SIF motoneurons, (2) examine immunolabeling patterns of ion channel proteins in the distinct motoneurons populations in the trochlear and abducens nuclei. Results: In the examination of the trochlear nucleus, a third motoneuron subgroup was consistently encountered with weak perineuronal nets (PN). The neurons of this subgroup had -on average- larger diameters than MIF motoneurons, and smaller diameters than SIF motoneurons, and PN expression strength correlated with neuronal size. Immunolabeling of various ion channels revealed that, in general, human MIF and SIF motoneurons did not differ consistently, as opposed to the findings in monkey trochlear and abducens nuclei. Kv1.1, Kv3.1b and HCN channels were found on both MIF and SIF motoneurons and the immunolabeling density varied for multiple ion channels. On the other hand, significant differences between SIF motoneurons and INTs were found in terms of HCN1 immunoreactivity. Discussion: These results indicated that motoneurons may be more variable in human in terms of histochemical and biophysiological characteristics, than previously thought. This study therefore establishes grounds for any histochemical examination of motor nuclei controlling extraocular muscles in eye movement related pathologies in the human brainstem.

Significance of new geometry of flow channels in proton exchange membrane fuel cell with comparing experimental and numerical methods.

The flow field geometry mainly affects the electrochemical reaction, the mass transfer, and gas diffusion layers. All these parameters affect the performance of a PEM fuel cell. In this study, a three-dimensional model is used for all parts of the fuel cell such as the flow channels, gas-diffusion electrodes, catalyst layers, and the membrane. These equations are numerically solved using a finite volume-based computational fluid dynamics technique to investigate the effect of using new geometries such as tubular, rectangular, elliptical, and triangular compared to planner-type fuel cells. Also, a test bench was designed and constructed for checking the cell and a series of experiments were done. The results show that there is good agreement between the numerical and experimental results. In summary, the tubular geometry has the best performance compared to others which can increase the execution of the fuel cell maximum by 43 %.

Exploration of the synergistic effect of chrysene-based core and benzothiophene acceptors on photovoltaic properties of organic solar cells.

To improve the efficacy of organic solar cells (OSCs), novel small acceptor molecules (CTD1-CTD7) were designed by modification at the terminal acceptors of reference compound CTR. The optoelectronic properties of the investigated compounds (CTD1-CTD7) were accomplished by employing density functional theory (DFT) in combination with time-dependent density functional theory (TD-DFT). The M06 functional along with a 6-311G(d,p) basis set was utilized for calculating various parameters such as: frontier molecular orbitals (FMO), absorption maxima (λmax), binding energy (Eb), transition density matrix (TDM), density of states (DOS), and open circuit voltage (Voc) of entitled chromophores. A red shift in the absorption spectra of all designed chromophores (CTD1-CTD7) was observed as compared to CTR, accompanied by low excitation energy. Particularly, CTD4 was characterized by the highest λmax value of 685.791 nm and the lowest transition energy value of 1.801 eV which might be ascribed to the robust electron-withdrawing end-capped acceptor group. The observed reduced binding energy (Eb) was linked to an elevated rate of exciton dissociation and substantial charge transfer from central core in HOMO towards terminal acceptors in LUMO. These results were further supported by the outcomes from TDM and DOS analyses. Among all entitled chromophores, CTD4 exhibited bathochromic shift (685.791 nm), minimum HOMO/LUMO band gap of 2.347 eV with greater CT. Thus, it can be concluded that by employing molecular engineering with efficient acceptor moieties, the efficiency of photovoltaic materials could be improved.

A reduced vector model predictive controller for a three-level neutral point clamped inverter with common-mode voltage suppression.

This paper presents a novel, state-of-the-art predictive control architecture that addresses the computational complexity and limitations of conventional predictive control methodologies while enhancing the performance efficacy of predictive control techniques applied to three-level voltage source converters (NPC inverters). This framework's main goal is to decrease the number of filtered voltage lifespan vectors in each sector, which will increase the overall efficiency of the control system and allow for common mode voltage reduction in three-level voltage source converters. Two particular tactics are described in order to accomplish this. First, a statistical approach is presented for the proactive detection of potential voltage vectors, with an emphasis on selecting and including the vectors that are most frequently used. This method lowers the computational load by limiting the search space needed to find the best voltage vectors. Then, using statistical analysis, a plan is presented to split the sectors into two separate parts, so greatly limiting the number of voltage vectors. The goal of this improved predictive control methodology is to reduce computing demands and mitigate common mode voltage. The suggested strategy's resilience is confirmed in a range of operational scenarios using simulations and empirical evaluation. The findings indicate a pronounced enhancement in computational efficiency and a notable diminution in common mode voltage, thereby underscoring the efficacy of the proposed methodology. This increases their ability to incorporate renewable energy sources into the electrical grid.

Sex-related differences in left atrial substrate among patients with atrial fibrillation: evidence from high-density voltage mapping.

BACKGROUND: There is sufficient evidence that women with atrial fibrillation (AF) have a greater symptom burden than men with AF and are more likely to experience recurrence after catheter ablation. However, the mechanisms underlying these sex differences are unclear. METHODS: We prospectively enrolled 125 consecutive patients, including 40 non-AF patients and 85 AF patients, who underwent high-density voltage mapping during sinus rhythm and AF patients who underwent first ablation. RESULTS: Overall, 37 (44%) female patients with AF and 24 (60%) female non-AF patients with a mean age of 61.7 ± 11.6 years and 53.6 ± 16.7 years, respectively, were enrolled in this study. The results showed that the atrial voltage of female AF patients was significantly lower than that of male AF patients (1.11 ± 0.58 mV vs. 1.53 ± 0.65 mV; P = 0.003), while there were no significant sex differences in non-AF patients (3.02 ± 0.86 mV vs. 3.21 ± 0.84 mV; P = 0.498). Multiple linear regression analysis revealed that female sex (- 0.29, 95% confidence interval [CI] - 0.64 to - 0.13, P = 0.004) and AF type (- 0.32, 95% CI - 0.69 to - 0.13, P = 0.004) were the only factors independently associated with voltage. Compared with men, women in the paroxysmal AF group had a 3.5-fold greater incidence of recurrence (adjusted hazard ratio 4.49; 95% CI 1.101-18.332, P = 0.036). Both globally and regionally, the results showed that sex-related differences in voltage values occurred prominently in paroxysmal AF patients but not in nonparoxysmal AF patients. CONCLUSION: Sex-related differences in atrial substrates and arrhythmia-free survival were found in paroxysmal AF patients, suggesting the existence of sex-related pathophysiological factors.

Crystallographic structure, antibacterial effect, and catalytic activities of fig extract mediated silver nanoparticles.

Silver nanoparticles (Ag NPs) play a pivotal role in the current research landscape due to their extensive applications in engineering, biotechnology, and industry. The aim is to use fig (Ficus hispida Linn. f.) extract (FE) for eco-friendly Ag NPs synthesis, followed by detailed characterization, antibacterial testing, and investigation of bioelectricity generation. This study focuses on the crystallographic features and nanostructures of Ag NPs synthesized from FE. Locally sourced fig was boiled in deionized water, cooled, and doubly filtered. A color change in 45 mL 0.005 M AgNO3 and 5 mL FE after 40 min confirmed the bio-reduction of silver ions to Ag NPs. Acting as a reducing and capping agent, the fig extract ensures a green and sustainable process. Various analyses, including UV-vis absorption spectrophotometry (UV), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDX) and Transmission electron microscopy (TEM) were employed to characterize the synthesized nanoparticles, and Gas chromatography-mass spectrometry (GC-MS) analysis of the fig extract revealed the presence of eleven chemicals. Notably, the Ag NPs exhibited a surface plasmon resonance (SPR) band at 418 nm, confirmed by UV analysis, while FTIR and XRD results highlighted the presence of active functional groups in FE and the crystalline nature of Ag NPs respectively. With an average particle size of 44.57 nm determined by FESEM and a crystalline size of 35.87 nm determined by XRD, the nanoparticles showed strong antibacterial activities against Staphylococcus epidermidis and Escherichia coli. Most importantly, fig fruit extract has been used as the bio-electrolyte solution to generate electricity for the first time in this report. The findings of this report can be the headway of nano-biotechnology in medicinal and device applications.

Advanced extraction of PV parameters' models based on electric field impacts on semiconductor conductivity using QIO algorithm.

This article presents a novel approach for parameters estimation of photovoltaic cells/modules using a recent optimization algorithm called quadratic interpolation optimization algorithm (QIOA). The proposed formula is dependent on variable voltage resistances (VVR) implementation of the series and shunt resistances. The variable resistances reduced from the effect of the electric field on the semiconductor conductivity should be included to get more accurate representation. Minimizing the mean root square error (MRSE) between the measured (I-V) dataset and the extracted (V-I) curve from the proposed electrical model is the main goal of the current optimization problem. The unknown parameters of the proposed PV models under the considered operating conditions are identified and optimally extracted using the proposed QIOA. Two distinct PV types are employed with normal and low radiation conditions. The VVR TDM is proposed for (R.T.C. France) silicon PV operating at normal radiation, and eleven unknown parameters are optimized. Additionally, twelve unknown parameters are optimized for a Q6-1380 multi-crystalline silicon (MCS) (area 7.7 cm2) operating under low radiation. The efficacy of the QIOA is demonstrated through comparison with four established optimizers: Grey Wolf Optimization (GWO), Particle Swarm Optimization (PSO), Salp Swarm Algorithm (SSA), and Sine Cosine Algorithm (SCA). The proposed QIO method achieves the lowest absolute current error values in both cases, highlighting its superiority and efficiency in extracting optimal parameters for both Single-Crystalline Silicon (SCS) and MCS cells under varying irradiance levels. Furthermore, simulation results emphasize the effectiveness of QIO compared to other algorithms in terms of convergence speed and robustness, making it a promising tool for accurate and efficient PV parameter estimation.

The recruitment of mechanosensitive enteric neurons in the guinea pig gastric fundus is dependent on ganglionic stretch level.

BACKGROUND: Serving as a reservoir, the gastric fundus can expand significantly, with an initial receptive and a following adaptive relaxation, controlled by extrinsic and intrinsic reflex circuits, respectively. We hypothesize that mechanosensitive enteric neurons (MEN) are involved in the adaptive relaxation, which is initiated when a particular gastric volume and a certain stretch of the stomach wall is reached. To investigate whether the responsiveness of MEN in the gastric fundus is dependent on tissue stretch, we performed mechanical stimulations in stretched versus ganglia "at rest". METHODS: Responses of myenteric neurons in the guinea pig gastric fundus were recorded with membrane potential imaging using Di-8-ANEPPS. MEN were identified by small-volume intraganglionic injection in ganglia stretched to different degrees using a self-constructed stretching tool. Immunohistochemical staining identified the neurochemical phenotype of MEN. Hexamethonium and capsaicin were added to test their effect on recruited MEN. KEY RESULTS: In stretched compared to "at rest" ganglia, significantly more MEN were activated. The change in the ganglionic area correlated significantly with the number of additional recruited MEN. The additional recruitment of MEN was independent from nicotinic transmission and the ratio of active MEN in stretched ganglia shifted towards a nitrergic phenotype. CONCLUSION AND INFERENCES: The higher number of active MEN with increasing stretch of the ganglia and their greater share of nitrergic phenotype might indicate their contribution to the adaptive relaxation. Further experiments are necessary to address the receptors involved in mechanotransduction.

Microbial fuel cell in long-term operation and providing electricity for intermittent aeration to remove contaminants from sewage.

Microbial fuel cells (MFCs) show promise in sewage treatment because they can directly convert organic matter (OM) into electricity. This study aimed to demonstrate MFCs stability over 750 days of operation and efficient removal of OM and nitrogenous compounds from sewage. To enhance contaminant removal, oxygen was provided into the anode chamber via a mini air pump. This pump was powered by the MFCs' output voltage, which was boosted using a DC-DC converter. The experimental system consisted of 12 sets of cylindrical MFCs within a 246L-scale reactor. The boosted voltage reached 4.7 V. This voltage was first collected in capacitors every 5 min and then dispensed intermittently to the air pump for the MFCs reactor in 4 s. This corresponds to receiving average DO concentration reaching 0.34 ± 0.44 mg/L at 10 cm above the air-stone. Consequently, the degradation rate constants (k) for chemical oxygen demand (COD) and biological oxygen demand (BOD) in the presence of oxygen were 0.048 and 0.069, respectively, which surpassed those without oxygen by 0.039 and 0.044, respectively. Aeration also marginally improved the removal of ammonia because of its potential to create a favorable environment for the growth of anammox and ammonia-oxidizing bacteria such as Candidatus brocadia and Nitrospira. The findings of this study offer in-depth insight into the benefits of boosted voltage in MFCs, highlighting its potential to enhance contaminant degradation. This serves as a foundation for future research focused on improving MFCs performance, particularly for the removal of contaminants from wastewater.

Output voltage control of DAB converters based on uncertainty and disturbance estimation.

The dual active bridge (DAB) converter is a power electronic device commonly used for DC voltage regulation and stabilization. However, during its control process, external disturbances, load variations, input voltage variations, switching tube voltage drops, dead time, etc. lead to errors in the control output, thus reducing the control accuracy of the system. Therefore, this article propose a robust control scheme for the output voltage based on uncertainty and disturbance estimator. In this article, an average small-signal model of the dual active bridge converter was established in terms of the basic principles and operation mechanisms, simplifying the controller's design. Then, the basic principles of the uncertainty and disturbance estimator (UDE) are introduced. The small-signal model of the dual active bridge (DAB) converter is applied to the UDE to minimize output voltage error by enabling the controller to directly regulate the shift ratio. Finally, this article discusses the application and effectiveness of the uncertainty and disturbance estimator (UDE) in the simulation and control of dual active bridge (DAB) converters. A series of experimental comparative studies are conducted, demonstrating that this scheme offers significant advantages in suppressing system uncertainties and disturbances.

Piezo2 voltage-block regulates mechanical pain sensitivity.

PIEZO2 is a trimeric mechanically-gated ion channel expressed by most sensory neurones in the dorsal root ganglia. Mechanosensitive PIEZO2 channels are also genetically required for normal touch sensation in both mice and humans. We previously showed that PIEZO2 channels are also strongly modulated by membrane voltage. Specifically, it is only at very positive voltages that all channels are available for opening by mechanical force. Conversely, most PIEZO2 channels are blocked at normal negative resting membrane potentials. The physiological function of this unusual biophysical property of PIEZO2 channels, however, remained unknown. We characterized the biophysical properties of three PIEZO2 ion channel mutations at an evolutionarily conserved Arginine (R2756). Using genome engineering in mice we generated Piezo2R2756H/R2756H and Piezo2R2756K/R2756K knock-in mice to characterize the physiological consequences of altering PIEZO2 voltage sensitivity in vivo. We measured endogenous mechanosensitive currents in sensory neurones isolated from the dorsal root ganglia and characterized mechanoreceptor and nociceptor function using electrophysiology. Mice were also assessed behaviourally and morphologically. Mutations at the conserved Arginine (R2756) dramatically changed the biophysical properties of the channel relieving voltage block and lowering mechanical thresholds for channel activation. Piezo2R2756H/R2756H and Piezo2R2756K/R2756K knock-in mice that were homozygous for gain of function mutations were viable and were tested for sensory changes. Surprisingly, mechanosensitive currents in nociceptors, neurones that detect noxious mechanical stimuli, were substantially sensitized in Piezo2 knock-in mice, but mechanosensitive currents in most mechanoreceptors that underlie touch sensation were only mildly affected by the same mutations. Single-unit electrophysiological recordings from sensory neurones innervating the glabrous skin revealed that rapidly-adapting mechanoreceptors that innervate Meissner's corpuscles exhibited slightly decreased mechanical thresholds in Piezo2 knock-in mice. Consistent with measurements of mechanically activated currents in isolated sensory neurones essentially all cutaneous nociceptors, both fast conducting Aδ-mechanonociceptors and unmyelinated C-fibre nociceptors were substantially more sensitive to mechanical stimuli and indeed acquired receptor properties similar to ultrasensitive touch receptors in Piezo2 knock-in mice. Mechanical stimuli also induced enhanced ongoing activity in cutaneous nociceptors in Piezo2 knock-in mice and hyper-sensitive PIEZO2 channels were sufficient alone to drive ongoing activity, even in isolated nociceptive neurones. Consistently, Piezo2 knock-in mice showed substantial behaviourally hypersensitivity to noxious mechanical stimuli. Our data indicate that ongoing activity and sensitization of nociceptors, phenomena commonly found in human chronic pain syndromes, can be driven by relieving the voltage-block of PIEZO2 ion channels. Indeed, membrane depolarization caused by multiple noxious stimuli may sensitize nociceptors by relieving voltage-block of PIEZO2 channels.

The role and mechanism of VDAC1 in type 2 diabetes: An underestimated target of environmental pollutants.

Type 2 diabetes (T2D) is a chronic metabolic disease that accounts for more than 90% of diabetic patients. Its main feature is hyperglycemia due to insulin resistance or insulin deficiency. With changes in diet and lifestyle habits, the incidence of T2D in adolescents has burst in recent decades. The deterioration in the exposure to the environmental pollutants further aggravates the prevalence of T2D, and consequently, it imposes a significant economic burden. Therefore, early prevention and symptomatic treatment are essential to prevent diabetic complications. Mitochondrial number and electron transport chain activity are decreased in the patients with T2D. Voltage-Dependent Anion Channel 1 (VDAC1), as a crucial channel protein on the outer membrane of mitochondria, regulates signal transduction between mitochondria and other cellular components, participating in various biological processes. When VDAC1 exists in oligomeric form, it additionally facilitates the entry and exit of macromolecules into and from mitochondria, modulating insulin secretion. We summarize and highlight the interplay between VDAC1 and T2D, especially in the environmental pollutants-related T2D, shed light on the potential therapeutic implications of targeting VDAC1 monomers and oligomers, providing a new possible target for the treatment of T2D.

An energy efficient control method of a photovoltaic system using a new three-phase inverter with a reduced common mode voltage.

This paper presents a new energy-efficient space vector pulse width modulation (SVPWM) for controlling the switches of a New three-phase inverter (NTPI) for photovoltaic (PV) applications to reduce switching losses, the peak value, and the dv/dt of the common mode voltage (CMV) with fewer number of switches. The proposed system offers a reliable operation in PV energy system with less leakage current and increased efficiency because of the reduction of the CMV, the source of leakage current in PV inverter-based application. Moreover, this also optimizes the operation of electric vehicle application with lower bearing failure. The performance of the proposed system with the new SVPWM is evaluated to the existing PWM in the literature, as well as the active zero state pulse width modulation (AZSPWM) of the two-level inverter introduced under identical conditions. Experiments and MATLAB simulations have both been used in this study.

Eugenol and lidocaine inhibit voltage-gated Na+ channels from dorsal root ganglion neurons with different mechanisms.

Eugenol (EUG) is a bioactive monoterpenoid used as an analgesic, preservative, and flavoring agent. Our new data show EUG as a voltage-gated Na+ channel (VGSC) inhibitor, comparable but not identical to lidocaine (LID). EUG inhibits both total and only TTX-R voltage-activated Na+ currents (INa) recorded from VGSCs naturally expressed on dorsal root ganglion sensory neurons in rats. Inhibition is quick, fully reversible, and dose-dependent. Our biophysical and pharmacological analyses showed that EUG and LID inhibit VGSCs with different mechanisms. EUG inhibits VGSCs with a dose-response relationship characterized by a Hill coefficient of 2, while this parameter for the inhibition by LID is 1. Furthermore, in a different way from LID, EUG modified the voltage dependence of both the VGSC activation and inactivation processes and the recovery from fast inactivated states and the entry to slow inactivated states. In addition, we suggest that EUG, but not LID, interacts with VGSC pre-open-closed states, according to our data.

Anion Substitution to Suppress the Voltage Hysteresis of Na3MnTi(PO4)3 as a Cathode Material for Sodium-Ion Batteries.

The Mn-based polyanion compound Na3MnTi(PO4)3 (NMTP) with a Na superionic conductor (NASICON) structure has attracted incremental attention as a potential cathode material for sodium-ion batteries. However, the occupation of Mn2+ on Na+ vacancies usually leads to severe voltage hysteresis, which in turn results in significant capacity loss, slow Na+ diffusion kinetics, and poor cycling stability. Herein, anion-substituted compounds Na3MnTi(PO4)3-x(SiO4)x (x = 0.1, 0.2, and 0.3) are synthesized. It reveals that the SiO44- substitution could induce partial oxidation of Mn2+ to Mn3+, and the latter has a lower occupancy preference on Na+ vacancies. By the proposed charge compensation strategy, the Mn2+ occupation on Na+ vacancies can be significantly suppressed. As a result, the voltage hysteresis is substantially inhibited, and greatly improved electrochemical performance is achieved. This study offers an alternative strategy to address the voltage hysteresis associated with NMTP and other Mn-based NASICON cathode materials.

Tau-mediated synaptic dysfunction is coupled with HCN channelopathy.

INTRODUCTION: In tauopathies, altered tau processing correlates with impairments in synaptic density and function. Changes in hyperpolarization-activated cyclic nucleotide-gated (HCN) channels contribute to disease-associated abnormalities in multiple neurodegenerative diseases. METHODS: To investigate the link between tau and HCN channels, we performed histological, biochemical, ultrastructural, and functional analyses of hippocampal tissues from Alzheimer's disease (AD), age-matched controls, Tau35 mice, and/or Tau35 primary hippocampal neurons. RESULTS: Expression of specific HCN channels is elevated in post mortem AD hippocampus. Tau35 mice develop progressive abnormalities including increased phosphorylated tau, enhanced HCN channel expression, decreased dendritic branching, reduced synapse density, and vesicle clustering defects. Tau35 primary neurons show increased HCN channel expression enhanced hyperpolarization-induced membrane voltage "sag" and changes in the frequency and kinetics of spontaneous excitatory postsynaptic currents. DISCUSSION: Our findings are consistent with a model in which pathological changes in tauopathies impact HCN channels to drive network-wide structural and functional synaptic deficits. HIGHLIGHTS: Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are functionally linked to the development of tauopathy. Expression of specific HCN channels is elevated in the hippocampus in Alzheimer's disease and the Tau35 mouse model of tauopathy. Increased expression of HCN channels in Tau35 mice is accompanied by hyperpolarization-induced membrane voltage "sag" demonstrating a detrimental effect of tau abnormalities on HCN channel function. Tau35 expression alters synaptic organization, causing a loosened vesicle clustering phenotype in Tau35 mice.

Dual polarity open circuit voltage in triboelectric nanogenerators originated from two states series impedance.

Experimental and simulation studies demonstrated that the initial voltage setting significantly influences the open-circuit voltage (VOC) in triboelectric nanogenerators (TENGs). Utilizing diode configurations, we consistently observed two distinct VOCs independent of the initial settings. A lower VOC corresponded to the surface voltage (VSurface), while a higher VOC was amplified by the product of the VSurface and the TENG's characteristic impedance ratio. Notably, a lower measurement system capacitance provided a more precise representation of the inherent characteristics of the TENG. Conversely, an increase in system impedance led to a convergence of the two VOCs and a reduction in their magnitudes relative to VSurface. These findings suggest that optimizing the initial/repeated charge balancing and minimizing capacitive loads are crucial for maximizing TENG output power in practical applications.

Analysis of ion transport properties of Glycine max HKT transporters and identifying a regulation of GmHKT1;1 by the non-functional GmHKT1;4.

The HKT transporter plays an important role for plants in response to salt stress, but the transport property of the soybean HKT transporters at the molecular level is still unclear. Here, using Xenopus oocyte as a heterologous expression system and two-electrode voltage-clamp technique, we identified four HKT transporters, GmHKT1;1, GmHKT1;2, GmHKT1;3, and GmHKT1;4, which all belong to type I subfamily, but having distinct ion transport properties. While GmHKT1;1, GmHKT1;2 and GmHKT1;3 function as Na+ transporters, GmHKT1;1 is less selective against K+ than the two other transporters. Astonishingly, GmHKT1;4, which lacks transmembrane segments and has no ion permeability, is significantly expressed, and its gene expression pattern is different from the other three GmHKTs under salt stress. Interestingly, GmHKT1;4 reduced the Na+/K+ currents mediated by GmHKT1;1. Further study showed that the transport ability of GmHKT1;1 regulated by GmHKT1;4 was related to the structural differences in the first intracellular domain and the fourth repeat domain. Overall, we have identified one unique GmHKT member, GmHKT1;4, which modulates the Na+ and K+ transport ability of GmHKT1;1 via direct interaction. Thus, we have revealed a new type of HKTs interaction model for altering their ion transport properties.