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0.6Bi(Mg1/2Ti1/2)O3–0.4Ba0.8Ca0.2(Nb0.125Ti0.875)O3 ceramics with a pseudo-cubic structure and re-entrant dipole glass behavior have been investigated via x-ray diffraction and dielectric permittivity–temperature spectra. It shows excellent dielectric–temperature stability with small variations of dielectric permittivity (±5%, 420–802 K) and dielectric loss tangent (tanδ < 2.5%, 441–647 K) in a wide temperature range. Three dielectric anomalies are observed from 290 to 1050 K. The low-temperature, weakly coupled re-entrant relaxor behavior was described using the Vogel–Fulcher law and the new glass model. The mid- and high-temperature dielectric anomalies are characterized by isothermal impedance and electrical modulus. The activation energy of both dielectric relaxation and conductivity follows the Arrhenius law in the temperature ranges of 633–753 and 833–973 K, respectively. The ultrahigh thermal stability of dielectric permittivity is attributed to the weak coupling of polar clusters, the formation of diffuse phase transition, and the local phase transition of calcium-containing perovskite. The results provide new insights into the defects behavior and the modification way of re-entrant relaxor behavior. [ABSTRACT FROM AUTHOR]

Conductive behavior research is vital for in-depth understanding the conductive capabilities of materials as well as promoting the development of their applications in fields such as electronics, energy and sensing. In the article, the AC conductive behavior was systematically evaluated for polymer-derived SiBCN ceramics by complex impedance spectroscopy and electrical modulus methods. The results suggest that SiBCN ceramics have a frequency-independent conductivity at low frequencies, whereas it exhibits a relaxation process with increasing frequency at high frequencies. In addition, the SiBCN ceramics follow the electron hopping conductive mechanism in both low and high-frequency bands over the testing temperature range. By considering the relationship between the prefactor σ 0 and T 0 , the conductive mechanism is revealed to be the band-tailed state hopping instead of the variable range hopping. It is worth noting that although the material has the same conductive mechanism at various testing temperatures, hopping is mainly controlled by the matrix phase at low frequencies; while at high frequencies, hopping is dominated by free carbon phase. Our results provide the underlying insights needed to guide the design of amorphous SiBCN ceramics for applications in electrically relevant fields. [ABSTRACT FROM AUTHOR]

[Display omitted] This study presents a novel Aluminium foil-based electrode characterized by its affordability, flexibility, and ease of modification with carboxylic moiety-containing organic molecules. Upon foil modification with Aluminium nanoparticles and EDTA (AlNP-EDTA/AlE), the modified electrode exhibits remarkable activity in the oxidation of lead at potentials around −0.4 V. The lead signal is derived from the oxidation of lead deposited on the electrode surface using anodic stripping voltammetry (ASV). The addition of EDTA to AlNP/AlE increased the anodic peak current of lead by more than 500 %. The surface characterization of the electrode was performed by scanning electron microscopy (SEM) and infrared spectroscopy (IR), while its electroactive properties were evaluated by cyclic voltammetry (CV) and electrical impedance spectroscopy (EIS). Optimal operating parameters include pH 2.1, square-wave voltammetry (SWV) with an accumulation time of 60 s and an accumulation potential of −0.8 V. A low detection limit of 0.20 µmol/L and a relative standard deviation (RSD) of 3.0 % were achieved using five different electrodes. The effectiveness of AlNP-EDTA/AlE was further demonstrated with consistent results in biological samples spiked with Pb. [ABSTRACT FROM AUTHOR]

Impedance spectroscopy assessed dielectric properties of PMN at a single PT concentration. Real and imaginary impedance of (1−x) PMN–xPT materials were analyzed using this technique. Through electrical impedance spectroscopy, the loss tangent factor and electric modulus were determined, leveraging research on semiconductor conduction. The study also presented the synthesis and characterization of solid ceramic lead magnesium nibate-lead titanate (1−x) PbMg1/3Nb2/3-xPbTi3, representing a significant advancement in impedance spectroscopy research. The dielectric behavior was examined by studying the polarization evolution in response to the applied field, aiming to replicate the magnetic phase boundary configuration found in typical ferroelectric behavior. Temperature had a notable impact on the hysteresis loop, with increasing temperature and decreasing applied field resulting in decreased leftover polarization and increased coercive field. The impedance and complex modulus graphs exhibited distinct semicircle patterns attributed to higher grain boundary resistance and capacitance compared to (1−x) PMN-xPT. The Nyquist plot highlighted bulk effects. [ABSTRACT FROM AUTHOR]

Seamless interfaces between electronic devices and biological tissues stand to revolutionize disease diagnosis and treatment. However, biological and biomechanical disparities between synthetic materials and living tissues present challenges at bioelectrical signal transduction interfaces. We introduce the active biointegrated living electronics (ABLE) platform, encompassing capabilities across the biogenic, biomechanical, and bioelectrical properties simultaneously. The living biointerface, comprising a bioelectronics layout and a Staphylococcus epidermidis-laden hydrogel composite, enables multimodal signal transduction at the microbial-mammalian nexus. The extracellular components of the living hydrogels, prepared through thermal release of naturally occurring amylose polymer chains, are viscoelastic, capable of sustaining the bacteria with high viability. Through electrophysiological recordings and wireless probing of skin electrical impedance, body temperature, and humidity, ABLE monitors microbial-driven intervention in psoriasis. [ABSTRACT FROM AUTHOR]

The temperature-dependent characterization of full tensor properties of single-domain relaxor-based single crystals (SCs) is important for understanding the influence of temperature on the properties of their multidomain SCs. However, no relevant results have been published because characterization is difficult to achieve using the traditional electric resonance method. In this Letter, the temperature-dependent elastic and piezoelectric properties of single-domain [111]c poled Mn-doped 28Pb(In1/2Nb1/2)O3-43Pb(Mg1/3Nb2/3)O3-29PbTiO3 SCs were investigated in the range of 20–80 °C by resonant ultrasound spectroscopy (RUS) using a rectangular parallelepiped sample. The temperature-dependent dielectric constants were calculated from the measured capacitances of the sample. The results are self-consistent because they were obtained from the same sample. The elastic constants obtained using the ultrasonic pulse-echo method agree closely with those obtained using RUS. Moreover, the experimental results of electric impedance spectrum agree closely with those simulated using the material constants characterized herein, indicating that the characterization is reliable. [ABSTRACT FROM AUTHOR]

A design method for an ultra-wideband coplanar-stripline-based vertical transition that can be used for ultra-high-speed digital interfaces is proposed. A conventional via structure, based on a differential line (DL), inherently possesses performance limitations (<10 GHz) due to difficulties in maintaining constant line impedance and smooth electric field transformation, in addition to the effects of signal skews, FR4 fiber weave, and unbalanced EM interferences. DL-based digital interfaces may not meet the demands of ultra-high-speed digital data transmission required for the upcoming 6G communications. The use of a coplanar stripline (CPS), a type of planar balanced line (BL), for the vertical transition, along with the ultra-wideband DL-to-CPS transition, mostly removes the inherent and unfavorable issues of the DL and enables ultra-high-speed digital data transmission. The design process of the transition is simplified using the analytical design formulas, derived using the conformal mapping method, of the transition. The characteristic line impedances of the transition are calculated and found to be in close agreement with the results obtained from EM simulations. Utilizing these results, the CPS-based vertical transition, maintaining the characteristic line impedance of 100 Ω, is designed and fabricated. The measured results confirm its ultra-wideband characteristics, with a maximum of 1.6 dB insertion loss and more than 10 dB return loss in the frequency range of DC to 30 GHz. Therefore, the proposed CPS-based vertical transition offers a significantly wider frequency bandwidth, i.e., more than three times that of conventional DL-based via structures. [ABSTRACT FROM AUTHOR]

Malaria is a disease that affects millions of people worldwide, particularly in developing countries. The development of accurate and efficient methods for the detection of malaria-infected cells is crucial for effective disease management and control. This paper presents the electrical impedance spectroscopy (EIS) of normal and malaria-infected red blood cells. An EIS microfluidic device, comprising a microchannel and a pair of coplanar electrodes, was fabricated for single-cell measurements in a continuous manner. Based on the EIS results, the aim of this work is to discriminate Plasmodium falciparum-infected red blood cells from the normal ones. Different from typical impedance spectroscopy, our measurement was performed for the cells in a low-conductivity medium in a frequency range between 50 kHz and 800 kHz. Numerical simulation was utilized to study the suitability parameters of the microchannel and electrodes for the EIS experiment over the measurement frequencies. The measurement results have shown that by using the low-conductivity medium, we could focus on the change in the conductance caused by the presence of a cell in the sensing electrode gap. The results indicated a distinct frequency spectrum of the conductance between the normal and infected red blood cells, which can be further used for the detection of the disease. [ABSTRACT FROM AUTHOR]

With the increase in groundwater exploration, underground mineral resource exploration, and non-destructive investigation of cultural relics, high-resolution earth electrical characteristic measurement has emerged as a mainstream technique owing to its advantageous non-destructive detection capability. To enhance the transmission power of the high-frequency transmitter in high-resolution multiple earth electrical characteristic measurement systems (MECS), this study proposes a high-frequency, high-current transmission technique based on adaptive impedance matching and implemented through the integration of resonant capacitors, a controllable reactor, high-frequency transformers, and corresponding control circuits. A high-current precisely controllable reactor with a 94% inductance variation range was designed and combined with resonant capacitors to reduce circuit impedance. Additionally, high-frequency transformers were employed to further increase the transmission voltage. A prototype was developed and tested, demonstrating an increase in transmission current at frequencies between 10 and 120 kHz with a peak active power of 200 W. Under the same transmission voltage, compared to the transmission circuit without impedance matching, the transmission current increased to a maximum of 16.7 times (average of 10.8 times), whereas compared to the transmission circuit using only traditional impedance matching, the transmission current increased by a maximum of 10.0 times (average of 4.2 times), effectively improving the exploration resolution. [ABSTRACT FROM AUTHOR]

Background: Ischaemic heart disease, including myocardial infarction, is one of the main causes leading to heart failure as a consequence of ischaemic myocardial damage. In recent years, survival in the acute phase of myocardial infarction has improved significantly, but the high mortality rate within 12 months of hospital discharge (reaching up to 9.8% in Poland) remains a challenge. Therefore, the KOS-Zawał (MC-AMI) comprehensive 12-month post-MI care programme was introduced in Poland in 2017. Aim: This study aimed to assess body composition (including, but not limited to, the phase angle, visceral fat, total body fat, redistribution between intracellular and extracellular fluid in the body, and metabolic age) using a bioelectrical impedance analysis (BIA) in post-MI patients before and after early post-MI rehabilitation who were participating in the KOS-Zawał (MC-AMI) programme. Methods: This study involved an examination (before rehabilitation) of 94 post-myocardial infarction patients who were referred to a cardiology appointment within 7–10 days of hospital discharge, during which a clinical assessment, electrocardiogram, and biochemical blood tests (complete blood count, CRP, and serum creatinine) were performed. For various reasons (death, qualification for device implantation, non-completion of rehabilitation, failure to attend a follow-up BIA), data from 55 patients who were examined twice (before and after rehabilitation) were used for the final analysis. Measurements were taken using a high-grade Tanita MC-780 BIA body composition analyser, which measured the resistance of tissues to a low-intensity electrical impulse (not perceptible to the subject). Results: Participation in rehabilitation as part of the KOS-Zawał (MC-AMI) programme was associated with a decrease in metabolic age in patients, with a reduction in visceral fat levels and levels of adipose tissue in the lower and upper limbs. Moreover, a clinically beneficial reduction in the ratio of extracellular water to total body water was also observed. These changes were statistically significant (p < 0.005). In contrast, there were no statistically significant differences in the change in phase angle values in the subjects before and after the 5-week post-infarction rehabilitation. Conclusions: Participation in early post-myocardial infarction rehabilitation as part of the KOS-Zawał (MC-AMI) programme (25 training sessions) is associated with significant improvements in body composition parameters, such as visceral adipose tissue, limb fat, and water redistribution, and, consequently, a reduction in metabolic age, despite no significant increase in phase angle values. It was hypothesised that the good baseline condition of the subjects might explain the lack of significant change in the phase angle over the short observation period. For further analysis, it would be worthwhile to increase the number of patients with baseline reduced phase angle values and monitor changes in this parameter throughout rehabilitation and the entire MC-AMI programme, because changes in the phase angle may also be influenced by other programme components such as dietary or psychological education. It is worth considering implementing a regular BIA assessment in patients in the programme as a motivating stimulus for diligent exercise and extending rehabilitation to be followed by telerehabilitation or hybrid telerehabilitation. [ABSTRACT FROM AUTHOR]

Sigma non-opioid intracellular receptor 1 (Sigma-1R) is an intracellular chaperone protein residing on the endoplasmic reticulum at the mitochondrial-associated membrane (MAM) region. Sigma-1R is abundant in the brain and is involved in several physiological processes as well as in various disease states. The role of Sigma-1R at the blood–brain barrier (BBB) is incompletely characterized. In this study, the effect of Sigma-1R activation was investigated in vitro on rat brain microvascular endothelial cells (RBMVEC), an important component of the blood–brain barrier (BBB), and in vivo on BBB permeability in rats. The Sigma-1R agonist PRE-084 produced a dose-dependent increase in mitochondrial calcium, and mitochondrial and cytosolic reactive oxygen species (ROS) in RBMVEC. PRE-084 decreased the electrical resistance of the RBMVEC monolayer, measured with the electric cell-substrate impedance sensing (ECIS) method, indicating barrier disruption. These effects were reduced by pretreatment with Sigma-1R antagonists, BD 1047 and NE 100. In vivo assessment of BBB permeability in rats indicates that PRE-084 produced a dose-dependent increase in brain extravasation of Evans Blue and sodium fluorescein brain; the effect was reduced by the Sigma-1R antagonists. Immunocytochemistry studies indicate that PRE-084 produced a disruption of tight and adherens junctions and actin cytoskeleton. The brain microcirculation was directly visualized in vivo in the prefrontal cortex of awake rats with a miniature integrated fluorescence microscope (aka, miniscope; Doric Lenses Inc.). Miniscope studies indicate that PRE-084 increased sodium fluorescein extravasation in vivo. Taken together, these results indicate that Sigma-1R activation promoted oxidative stress and increased BBB permeability. [ABSTRACT FROM AUTHOR]

Gd/Cr co-doped SrBi 4 Ti 4 O 15 (Sr 1- x Gd x Bi 4 Ti 4 O 15 + 0.2 wt% Cr 2 O 3 , x = 0∼0.08) Aurivillius-phase ceramics were prepared by the traditional solid-state reaction process, the influences of Gd3+ doping concentration (x) on the structures and electrical properties of SrBi 4 Ti 4 O 15 were investigated, as well as the AC impedance characterizations of the ceramics were analyzed. The incorporation of Gd 2 O 3 and Cr 2 O 3 into SrBi 4 Ti 4 O 15 induced the lattice distortion of its orthorhombic structure. The donor substitution of Gd3+ for Sr2+ at A-site improved the Curie temperature (T C) and decrease the temperature coefficient of dielectric constant (TK ε), as well as change the relaxation activation energy (E a rel) of SrBi 4 Ti 4 O 15 through the lattice distortion caused. Between 425 °C and 700 °C, the DC conduction behaviors of the ceramics was found with a transition from the mixed conduction mechanism involved in both the single-ionized oxygen vacancy and the double-ionized one to the single mode dominated by the latter one. Above T C , the imaginary part of modulus (M″) gradually shifts towards higher frequencies with increasing temperature, indicating the emergence of a new dielectric relaxation mode related to the phase transition process of the ceramics. Owing to the co-doping effects of Gd3+ and Cr3+, the optimized composition with x = 0.03 achieved excellent electrical properties (T C = 550 °C and d 33 = 30 pC/N) and good thermal stability (TK ε = 4.19 × 10−3/°C between RT and 500 °C, and the lose in d 33 is only 3.3% after being annealed at 500 °C for 4 h), which make it promising for stable applications below 500 °C in the high-temperature piezoelectric devices. [ABSTRACT FROM AUTHOR]

Purpose: Assessing efficacy of electrical impedance tomography (EIT) in optimizing positive end-expiratory pressure (PEEP) for acute respiratory distress syndrome (ARDS) patients to enhance respiratory system mechanics and prevent ventilator-induced lung injury (VILI), compared to traditional methods. Methods: We carried out a systematic review and meta-analysis, spanning literature from January 2012 to May 2023, sourced from Scopus, PubMed, MEDLINE (Ovid), Cochrane, and LILACS, evaluated EIT-guided PEEP strategies in ARDS versus conventional methods. Thirteen studies (3 randomized, 10 non-randomized) involving 623 ARDS patients were analyzed using random-effects models for primary outcomes (respiratory mechanics and mechanical power) and secondary outcomes (PaO2/FiO2 ratio, mortality, stays in intensive care unit (ICU), ventilator-free days). Results: EIT-guided PEEP significantly improved lung compliance (n = 941 cases, mean difference (MD) = 4.33, 95% confidence interval (CI) [2.94, 5.71]), reduced mechanical power (n = 148, MD = − 1.99, 95% CI [− 3.51, − 0.47]), and lowered driving pressure (n = 903, MD = − 1.20, 95% CI [− 2.33, − 0.07]) compared to traditional methods. Sensitivity analysis showed consistent positive effect of EIT-guided PEEP on lung compliance in randomized clinical trials vs. non-randomized studies pooled (MD) = 2.43 (95% CI − 0.39 to 5.26), indicating a trend towards improvement. A reduction in mortality rate (259 patients, relative risk (RR) = 0.64, 95% CI [0.45, 0.91]) was associated with modest improvements in compliance and driving pressure in three studies. Conclusions: EIT facilitates real-time, individualized PEEP adjustments, improving respiratory system mechanics. Integration of EIT as a guiding tool in mechanical ventilation holds potential benefits in preventing ventilator-induced lung injury. Larger-scale studies are essential to validate and optimize EIT's clinical utility in ARDS management. [ABSTRACT FROM AUTHOR]

The present study explores a nano-grained perovskite material for use in an intermediate-temperature solid oxide fuel cell. Electrolytes with the formula Ba1−xCaxCe0.8Nd0.2O3−δ (BCCN), where x = 0.0, 0.01, 0.02, 0.03, 0.04, and 0.05, were synthesized through the sol–gel auto-combustion process. Structural, surface morphology and vibrational analyses were conducted through XRD, SEM, FTIR, and Raman studies. Scherer's formula revealed predicted crystallite sizes for the electrolyte materials ranging from 25.13 to 38.69 nm. Morphological assessments determined grain diameters between 1 to 3 µm. Raman spectroscopy identified the 355 cm−1 vibrational mode associated with CeO6 octahedra, while FT-IR identified bands corresponding to M–O vibrations. Electrical impedance spectroscopy results indicated ionic behavior conducive to electrolytes, with overall conductivities increasing with measurement temperature. Notably, bulk conductivity surpassed grain boundary conductivity, with the highest overall conductivity observed in x = 0.05 compositions among the examined perovskite oxides. [ABSTRACT FROM AUTHOR]

Lidocaine is the most frequently applied local infiltration anesthetic agent for treating tendinopathies. However, studies have discovered lidocaine to negatively affect tendon healing. In the current study, the molecular mechanisms and effects of lidocaine on tenocyte migration were evaluated. We treated tenocytes intrinsic to the Achilles tendons of Sprague–Dawley rats with lidocaine. The migration ability of cells was analyzed using electric cell‐substrate impedance sensing (ECIS) and scratch wound assay. We then used a microscope to evaluate the cell spread. We assessed filamentous actin (F‐actin) cytoskeleton formation through immunofluorescence staining. In addition, we used Western blot analysis to analyze the expression of phospho‐focal adhesion kinase (FAK), FAK, phospho‐paxillin, paxillin, and F‐actin. We discovered that lidocaine had an inhibitory effect on the migration of tenocytes in the scratch wound assay and on the ECIS chip. Lidocaine treatment suppressed cell spreading and changed the cell morphology and F‐actin distribution. Lidocaine reduced F‐actin formation in the tenocyte during cell spreading; furthermore, it inhibited phospho‐FAK, F‐actin, and phospho‐paxillin expression in the tenocytes. Our study revealed that lidocaine inhibits the spread and migration of tenocytes. The molecular mechanism potentially underlying this effect is downregulation of F‐actin, phospho‐FAK, and phospho‐paxillin expression when cells are treated with lidocaine. [ABSTRACT FROM AUTHOR]

We examine the use of time series data, derived from Electric Cell-substrate Impedance Sensing (ECIS), to differentiate between standard mammalian cell cultures and those infected with a mycoplasma organism. With the goal of easy visualization and interpretation, we perform low-dimensional feature-based classification, extracting application-relevant features from the ECIS time courses. We can achieve very high classification accuracy using only two features, which depend on the cell line under examination. Initial results also show the existence of experimental variation between plates and suggest types of features that may prove more robust to such variation. Our paper is the first to perform a broad examination of ECIS time course features in the context of detecting contamination; to combine different types of features to achieve classification accuracy while preserving interpretability; and to describe and suggest possibilities for ameliorating plate-to-plate variation. [ABSTRACT FROM AUTHOR]

It is thought that esophageal hypersensitivity in combination with an impaired mucosal barrier function contributes to PPI-resistant reflux symptoms. Ziverel, a bioadhesive agent that coats the esophageal wall, was shown to have a positive effect on reflux symptoms. However, the mechanisms of action are unclear. We aimed to assess the effect of Ziverel on esophageal sensitivity to acid and mucosal barrier function. We performed a double-blind randomized placebo-controlled crossover trial in PPI-refractory patients with reflux symptoms. Patients were assigned (1:1) to 14 days of Ziverel followed by 14 days of placebo or opposite treatment order. The effect was evaluated using acid perfusion tests, an upper endoscopy with electrical tissue impedance spectroscopy (ETIS) and esophageal biopsies. The primary outcome was the esophageal sensitivity based on perfusion sensitivity score. Secondary outcomes included mucosal barrier function and reflux symptoms and correlations between the different outcomes. Perfusion sensitivity score was not significantly different during treatment with Ziverel (106 (73–115)) and placebo (102 (67–110)) (p = 0.508) along with total RDQ score (2.6 (1.9–3.3) vs 2.8 (1.6–3.5) p = 0.456). ETIS showed comparable values during treatment with Ziverel (13514 (8846–19734)Ω·m) and placebo (13217 (9127–24942)Ω·m (p = 0.650)). Comparing Ziverel and placebo no difference was seen in transepithelial electrical resistance (TEER) 203 (163–267) Ω.cm2 vs 205 (176–240) Ω.cm2 (p = 0.445) and fluorescein flux 775 (17–6964) nmol/cm2/h vs 187 (4–12209) nmol/cm2/h (p = 0.638). Ziverel did not show a benefit on acid sensitivity, reflux symptoms or esophageal mucosal integrity compared to placebo in PPI-refractory patients with reflux symptoms. Trial registration: Netherlands Trial Register number: NL7670 [ABSTRACT FROM AUTHOR]

Solid polymer electrolyte blends with varied compositions of poly(ethylene oxide) (PEO)/carboxymethyl cellulose (Na-CMC) in 10/90, 50/50, and 90/10 compositions have been successfully prepared by means of the solution cast technique at room temperature. The modification of the structural, optical, and electrical properties of the prepared blend samples was studied by employing XRD, FTIR, UV-Vis, and electrical impedance spectroscopy methods. X-ray diffraction studies revealed that the crystalline nature gradually transforms into amorphous as the Na-CMC content increases in the sample. The variation of bands noticed in the Fourier transform infrared spectroscope characteristic spectrum of the blends reveals the formation of complexes between the individual polymers. The analysis of optical properties using a UV-Vis spectrometer in the wavelength range of 900–1100nm, shows a gradual decrease in the optical indirect energy band gap with an increase in Na-CMC content in the blend. The study of the electrical properties of the blend carried out in the frequency range 50 Hz–1MHz and temperature range 303K–338K, using an electrical impedance analyzer reveals that, the dielectric constant and loss decrease with the rise in frequency, exhibiting the usual behavior of the polymers. AC conductivity is found to increase with an increase in temperature. The highest value of ionic conductivity is found to be 6.06 × 10−3Scm−1 for the blend with a 10/90 composition. [ABSTRACT FROM AUTHOR]

Electrical impedance spectroscopy (EIS) has been proposed as a promising noninvasive method to differentiate healthy thyroid from parathyroid tissues during thyroidectomy. However, previously reported similarities in the in vivo measured spectra of these tissues during a pilot study suggest that this separation may not be straightforward. We utilise computational modelling as a method to elucidate the distinguishing characteristics in the EIS signal and explore the features of the tissue that contribute to the observed electrical behaviour. Firstly, multiscale finite element models (or 'virtual tissue constructs') of thyroid and parathyroid tissues were developed and verified against in vivo tissue measurements. A global sensitivity analysis was performed to investigate the impact of physiological micro-, meso- and macroscale tissue morphological features of both tissue types on the computed macroscale EIS spectra and explore the separability of the two tissue types. Our results suggest that the presence of a surface fascia layer could obstruct tissue differentiation, but an analysis of the separability of simulated spectra without the surface fascia layer suggests that differentiation of the two tissue types should be possible if this layer is completely removed by the surgeon. Comprehensive in vivo measurements are required to fully determine the potential for EIS as a method in distinguishing between thyroid and parathyroid tissues. [ABSTRACT FROM AUTHOR]

This manuscript delves into the multifaceted exploration of the perovskite ceramic (Bi 0.5 Ba 0.5 Ag) 0.5 (NiMn) 0.5 O 3 , synthesized via the sol-gel technique. Unveiling the structural, morphological, dielectric, and electrical facets, the material's orthorhombic structure, affirmed through Rietveld-refined XRD data, showcases an average crystallite size of approximately 33 nm. Dielectric investigations illuminate the presence of Maxwell-Wagner-type dispersion, hinting at charge accumulation along grain boundaries and interfaces. Employing complex impedance and electric modulus analyses reveals microscopic dielectric relaxation intricacies and the material's conduction mechanisms. Electric modulus spectroscopy uncovers non-Debye-type relaxation, encompassing both localized and long-range processes. Nyquist plots attest to the ceramic's semiconducting nature. Applying the Arrhenius law to the imaginary part of electrical impedance and conductivity yields activation energies and relaxation times, significantly enriching our understanding of the material's electrical properties. This comprehensive scrutiny unravels the ceramic's potential applications, offering fresh insights for diverse device implementations. [ABSTRACT FROM AUTHOR]

The modelling and analysis of high‐frequency bearing voltage are of great significance to the assessment and mitigation of the electrical erosion risk in wind power systems. However, the dual‐winding permanent magnet synchronous generator (DW‐PMSG), as one of the mainstream models in wind power industry, has not been specifically analysed for its bearing voltage modelling method in the existing research. The high frequency common mode equivalent circuit model of DW‐PMSG is established, and the effect of parasitic parameters between two sets of winding on bearing voltage is analysed. A model parameters extraction method based on differential evolution algorithm is proposed, and the range of parameters is estimated by finite element simulation and test results, which improves the search efficiency and solution accuracy. The accuracy of the proposed model is verified by the comparison of simulation and experimental results. On this basis, it is possible to conduct more in‐depth research on the bearing voltage and bearing currents of DW‐PMSG, and provide theoretical basis and simulation means for the design of suppression schemes. [ABSTRACT FROM AUTHOR]

Bubble columns are used in the mining industry for mineral recovery but are also widely utilized in the chemical and petrochemical industry. The hydrodynamic characteristics of their performance is a field of interest with a number of points, which are nonetheless poorly understood, and a considerable amount of methods have aimed to shed light on the flow regimes that prevail in the columns. The study of the hydrodynamic part of a flotation process should consider characteristics such as air flow, volumetric gas fraction, flow field, and bubble size, along with the mechanical and design factors and pulp properties. The present work aims to elucidate the characteristics of the gas phase of a hybrid flotation system. For this purpose, a hybrid flotation column was designed and constructed and the bubbles size distributions at different radial positions in the flotation column were computed by analyzing high resolution digital images. A patented electrical impedance technique was employed to instantaneously measure the local volumetric gas fraction. Flow dispersion in the column was studied by residence time distributions using conductivity tracers. The experimental results are discussed to comprehend the variation in the gas fraction in the column. In particular, the study showed that the size of the bubbles changed from the center to the walls of the column, and this was observed both radically and vertically. Moreover, the size of the bubbles affected the volume fractions, and no coalescence of the bubbles was observed. Finally, the dispersion of the tracer in the working solution was distributed uniformly in the volume of the column, with a time difference for the four positions of the column. [ABSTRACT FROM AUTHOR]

A soft piezoceramic multilayer (ML) bending thin and thick dual-actuators side-by-side device, for use in bone-conduction hearing aids (BCHA), was characterized experimentally. For this purpose, first, quasi-static (0.1 Hz square wave) transverse displacements (deflections) of each ML bender were measured using a laser vibrometer (LV) under unimorph and bimorph drivings at various non-amplified peak (p) voltages (1Vp–13Vp). The resulting peak displacement–voltage curves were found clearly nonlinear, indicating a pronounced piezoelectric (PE) field-dependent nonlinearity (FDNL). Then, experimental electric impedance analyses were conducted for each ML bender, using an impedance analyzer, under 1Vpunimorph driving for the whole audio frequency range (20 Hz–20 kHz). The identified three modes' superposed impedance magnitudes and phases showed their increasing deviation to the frequency scale left with increasing the modes' order, indicating a possible softening elastic FDNL, as confirmed later by harmonic frequency response LV measurements at 1Vp. Finally, the harmonic frequency responses, for the above audio frequency range, were measured for each ML bender using the LV under unimorph and bimorph drivings at various non-amplified voltages (1Vp–10Vp). Here, beside the PE FDNL, the frequency response functions showed clearly a pronounced softening elastic FDNL. Consequently, with increasing input voltages, the identified two modes' displacement amplitudes were nonlinearly increasing, while resonant frequencies and corresponding quality factors were nonlinearly decreasing. The three parameters-voltage curves were found to fit well (R2 ≈ 1) with high-order polynomials. These experimental results contradict the widely assumed displacement–potential linearity of middle ear or BCHA implantable PE vibrators of open literature available types (with or without shim bimorphs, unimorphs or diaphragms, and stacks) under similar targeted driving voltage and frequency ranges. The ML benders type quasi-static, frequency response and electric impedance characterizations, as well as the dual actuators side-by-side device, are proposed here for the first time for hearing aid applications. [ABSTRACT FROM AUTHOR]

The anodization of pure aluminum (Al) thin films of 0.5 μm thick on Titanium nitride/Silicon (TiN/Si) substrate in the lithium-based electrolytes at 2.5 V was performed to form porous and mesh morphologies of alumina–lithium composites. The electrochemical analysis through the anodization process and the morphology using a scanning electron microscope of the obtained porous alumina–lithium composites were discussed. The anodization of Al/TiN/Si films in lithium-based electrolytes resulted in the synthesis of ultra-thin walls porous anodic alumina (PAA) with incorporated lithium ions confirmed by Raman spectroscopy. The impedance spectroscopy was performed to study the influence of incorporated lithium ions into the PAA matrix on its electronic properties. The impedance spectroscopy analysis revealed an improvement in the electrical impedance of the formed PAA compared to the insulated alumina. In addition, its impedance data show a capacitance behavior with a low series resistance value which can be exploited for high-performance battery applications. [ABSTRACT FROM AUTHOR]

The precise manipulation of neural activity is of great significance to reveal the function of complex neural circuits in brain, especially the mechanism of neurological disorders such as epilepsy, Parkinson's, and Alzheimer's disease. In the past decades, optogenetics has become a powerful tool to investigate the function of neural circuits due to its unique advantages of cell specificity and high spatiotemporal resolution. However, to date, most optogenetic manipulation has been conducted in an open‐loop fashion. The closed‐loop neural modulation is still an important task. Here, a closed‐loop optogenetic modulation system is developed for ultra‐fast, ‐accurate, and ‐stable manipulation of neural activities in behaving mice. Specifically, this system is mediated by a functional fiber probe with excellent low optical loss (0.052 dB cm−1 at 589 nm) and electrical impedance (5.40 MΩ µm−2 at 1 kHz). In vivo electrophysiology and behavioral experiments demonstrated that the system can be successfully applied for the identification and intervention of seizures in epilepsy mice with high efficiency. It is envision that the closed‐loop manipulation system has promising applications in brain science, neuroscience, and neuromodulation therapies. [ABSTRACT FROM AUTHOR]

Summary: The fraudulent practice of beef adulteration is a growing concern, as it violates consumer rights. Electrical impedance spectroscopy (EIS) combined with machine learning has emerged as a widely used approach to identify low‐quality meat. Unlike traditional biochemical methods that require expensive instruments, complex sample preparation, and chemical reagents, EIS is a cost‐effective alternative. However, EIS data are susceptible to temperature fluctuations, requiring a waiting period under consistent temperature conditions for data stabilisation before measurements. This process becomes impractical when dealing with a large number of samples. To overcome this limitation, standardisation, normalisation, and smoothing methods were introduced in the meat quality detection based on EIS data. A recognition model for detecting carrageenan adulteration in beef was established. Under an inconsistent temperature condition, by applying the spectra pre‐processing methods to the prediction dataset, the model accuracy reached 84%, whereas the accuracy of the unprocessed prediction dataset dropped to 54%. This study demonstrates that acquiring EIS data under consistent temperature conditions is unnecessary if proper spectra pre‐processing methods are applied. By eliminating the waiting time for data stabilisation, this practical approach enhances the efficiency and accuracy of meat quality detection. [ABSTRACT FROM AUTHOR]

Surface electromyography (sEMG) is a technique for measuring and analyzing the electrical signals of muscle activity using electrodes placed on the skin's surface. The aim of this paper was to outline the history of the development and use of surface electromyography in dentistry, to show where research and technical solutions relating to surface electromyography currently lie, and to make recommendations for further research. sEMG is a diagnostic technique that has found significant application in dentistry. The historical section discusses the evolution of sEMG methods and equipment, highlighting how technological advances have influenced the accuracy and applicability of this method in dentistry. The need for standardization of musculoskeletal testing methodology is highlighted and the needed increased technical capabilities of sEMG equipment and the ability to specify parameters (e.g., sampling rates, bandwidth). A higher sampling rate (the recommended may be 2000 Hz or higher in masticatory muscles) allows more accurate recording of changes in the signal, which is essential for accurate analysis of muscle function. Bandwidth is one of the key parameters in sEMG research. Bandwidth determines the range of frequencies effectively recorded by the sEMG system (the recommended frequency limits are usually between 20 Hz and 500 Hz in masticatory muscles). In addition, the increased technical capabilities of sEMG equipment and the ability to specify electromyographic parameters demonstrate the need for a detailed description of selected parameters in the methodological section. This is necessary to maintain the reproducibility of sEMG testing. More high-quality clinical trials are needed in the future. [ABSTRACT FROM AUTHOR]

To obtain both the intensities and phases of electric fields, it is necessary to calibrate the data observed by the sensor by consulting the sensor characteristics. The frequency profile of the sensor impedance obtained from the simulation is roughly consistent with that obtained from the theory. However, some differences are identified in the frequency profile of the sensor impedance obtained from the simulation compared to the theory. We conducted simulations using the particle-in-cell (PIC) simulation tool to analyze the impedance of electric field sensors immersed in magnetized space plasmas. The simulation model comprised a dipole sensor placed in a three-dimensional simulation box filled with electrons and ions. The dipole sensor was represented by perfect conductor rods. We carefully selected simulation parameters and employed an appropriate feeding technique to accurately evaluate the sensor impedance. We observed significant changes in the frequency dependence of the sensor impedance as cyclotron frequency varied. To understand the simulation results, we introduced the linear dispersion relation. By comparing the real part of the sensor impedance with the ω - k diagram, we found that the impedance peaks corresponded to frequencies at which branches of plasma waves were present, with k = k half , representing half the wavelength equal to the tip-to-tip sensor length, i.e., the sensor can be assumed as the half-wavelength dipole antenna. [ABSTRACT FROM AUTHOR]

Objective: This study investigated the relationship of anthropometric and metabolic risk factors with seminal and sex steroidal hormone parameters in a screened population of healthy males. Methods: The participants were healthy young men without chronic or congenital diseases. The body composition parameters that we investigated were measured weight, height, and waist circumference (WC), as well as bioelectrical impedance analysis. Semen samples were analyzed for semen volume, sperm concentration, sperm motility and morphology, seminal pH, and liquefaction time. Biochemistry analysis, including glucose and lipid metabolism parameters, was conducted on fasting blood samples. Testicular volume was calculated separately for each testis using ultrasonography. Results: Body mass index exhibited an inverse association with total sperm count. WC showed negative correlations with numerous seminal parameters, including sperm concentration, total sperm count, sperm morphology, and follicle-stimulating hormone levels. The basal metabolic rate was associated with seminal pH, liquefaction time, and sperm motility. WC, fat mass percentage, and triglyceride levels exhibited negative correlations with sex hormone binding globulin. The measures of glucose metabolism were associated with a greater number of seminal parameters than the measures of cholesterol metabolism. C-reactive protein levels were inversely associated with sperm concentration and total sperm count. Conclusion: Anthropometric and metabolic risk factors were found to predict semen quality and alterations in sex steroidal hormone levels. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cells adherence provides specific information about physiology and pathology, the adhesion measurement between living cells and nanostructures can be measured by atomic force microscopy, but this detection technique is difficult to operate and costly. The adhesion height and effective contact area between cells and substrates are also the key factors affecting measurement value of the overall impedance. These factors change with structural parameters of the substrates, so the adhesion measurement between living cells and substrate can be indirectly reflected by the impedance value. OBJECTIVE: To establish a mapping relationship between the impedance measurement and the adhesion measurement of living cells. The possibility of dynamic measurement of adhesion is realized by this method, and the experimental process is simplified. METHODS: Laser interference technology was used to prepare nanoarray structures with different periods on the surface of silicon wafers for cells culture. Under the same experimental conditions, the impedance of living cells on the substrates of different cycle sizes were measured. The adhesion between cells and different substrates were analyzed by measuring impedance after the interaction between cells and substrate. RESULTS: The adhesion of living cells on the substrates of different sizes be analyzed, and the mapping relationship between the impedance and the adhesion measurement was established. The results showed that, the larger the impedance value between cells and substrate, the larger the effective contact area and the smaller the gap between them. CONCLUSION: The difference of adhesion height and effective adhesion area between living cells and substrates were obtained. This paper, a new method to measure the adhesion properties of living cells is presented, which provides theoretical basis for the related research. [ABSTRACT FROM AUTHOR]

Post-stroke complex regional pain syndrome (CRPS) poses challenges in pain assessment for survivors. Stellate ganglion block (SGB) is a treatment, but evaluating its effectiveness is difficult for patients with communication limitations. Edema, a prominent symptom, can serve as an evaluation marker. Bioelectrical impedance analysis (BIA), assessing body composition and fluid status, is used independently of patient cooperation. This retrospective, observational pilot study aims to explore BIA's utility as an assessment tool post-SGB, revealing the effects and time courses of a single SGB on the bodily composition of post-stroke CRPS patients. Seven patients received ultrasound-guided SGB with a 5 mL solution containing 4 mL of 0.25% bupivacaine hydrochloride and 40 mg of triamcinolone into the prevertebral muscle space. BIA compared measures between affected and unaffected arms. The affected arm had higher segmental body water (SBW) and extracellular water ratios before SGB (p = 0.028 and p = 0.018, respectively). The SBW of the affected side, the SBW ratio, and the 1 and 5 kHz SFBIA ratios improved over time (p = 0.025, 0.008, 0.001, and 0.005, respectively). Rapid improvement occurred around 3 days post-injection, with maximum effects within approximately 1 week, persisting up to 3 weeks. SGB successfully reduced edema in post-stroke CRPS patients, with BIA serving as a useful tool for follow-up, facilitating the development of efficient treatment plans. [ABSTRACT FROM AUTHOR]

Introduction: body composition (BC) analysis is an essential element in clinical nutritional practice. Bioelectrical impedance is one of the most widely used techniques for estimating BC. Several approaches have been proposed to reduce the margin of error it presents, ensuring its application in all populations. One of them is the use of impedance vectors, using tolerance ellipses. Objective: to compare the sample vectors with the Italian population and to determine specifi c tolerance ellipses for the Colombian university population. Materials and Methods: observational cross-sectional study in 608 university students. Participation was at convenience and voluntary, between February 2022 and March 2023. BIVA 2002 software was used to calculate the tolerance ellipses and BIVA confi dence to compare the vectors of the ellipses with the Italian population using Hotelling's T2 test, which was considered as signifi cant at p < 0.05. Results: R/H and Xc/H measurements were higher in females (420.75 ± 56.012 O/m vs 308.7508 ± 41.81 O/m) and (46.15 ± 5.79 O/m vs 39.44 ± 5.01 O/m), respectively. The impedance vectors were positioned over the upper quadrants of the RXc plot, evidencing signifi cant differences in the distribution of the composition vectors between samples. Conclusions: the vectors of the Colombian university students were different from the reference population, so it was necessary to determine the specifi c ellipses. [ABSTRACT FROM AUTHOR]

The rapid detection of moisture content in tomato leaves can provide an important basis for tomato cultivation. Compared with spectroscopy technology, image technology, and dielectric detection technology, electrical impedance spectroscopy (EIS) has the potential to analyze the internal components of leaf microstructure qualitatively and quantitatively, and the characteristics of fast detection and low cost. The moisture content in tomato leaves was detected effectively and accurately at the anthesis of the first inflorescence using the EIS method. The influence of reduction of moisture content on the impedance characteristics and equivalent circuit parameters was analyzed. The frequencies of different impedance characteristics were selected based on the out-of-bag (OOB) importance. Different regression algorithms, including partial least square regression (PLSR), back-propagation neural network (BPNN), and random forest (RF), were used for estimating the leaf moisture content (LMC). The LMC models based on different impedance characteristics and different methods were established and compared. The results demonstrated that the impedance modulus in the low-frequency region, the extracellular resistance (Re), and the intracellular resistance (Ri) increased first and then decreased with the decrease in the moisture content of the tomato leaves. The RF model established with the combination data had the best performance, with the coefficient of determination (R2), normalized root-mean-square error (NRMSE), and the ratio of performance of deviation (RPD) for prediction being 0.8861, 6.02%, and 2.95, respectively. Therefore, the EIS method combined with RF was a feasible and effective method to predict LMC, providing a promising tool for moisture content detection. [ABSTRACT FROM AUTHOR]

A model expressing beams, pillars, and electrical wiring in a building for lightning surge simulation by circuit analysis method is proposed in this paper. The proposed model expresses the self‐surge impedance of the electrical wiring as a function of the distance between conductors and the radius of the electrical wiring. The mutual impedance is expressed by the distance between the surfaces of a structure and a nearby wire instead of the distance between the conductor centers. In the case of two conductors having far different radii in proximity, the distribution of electromagnetic fields around the two conductors is similar in horizontal and vertical arrangements. Thus, the electrical wiring nearby pillars can be treated as a horizontal conductor. The circuit analysis results show that the voltage difference generated between the structure and the electrical wiring is calculated more precisely by the proposed model than by the conventional model. [ABSTRACT FROM AUTHOR]

Amyloid plays a critical role in the pathogenesis of Alzheimer's disease (AD) and can aggregate to form oligomers and fibrils in the brain. There is increasing evidence that highly toxic amyloid-β oligomers (AβOs) lead to tau protein aggregation, hyperphosphorylation, neuroinflammation, neuronal loss, synaptic loss, and dysfunction. Although the effects of AβOs on neurons have been investigated using conventional biochemical experiments, there are no established criteria for electrical evaluation. To this end, we explored electrophysiological changes in mouse hippocampal neurons (HT22) following exposure to AβOs and/or naringenin (Nar, a flavonoid compound) using electrical impedance spectroscopy (EIS). AβO-induced HT22 showed a decreased impedance amplitude and increased phase angle, and the addition of Nar reversed these changes. The characteristic frequency was markedly increased with AβO exposure, which was also reversed by Nar. The AβOs decreased intranuclear and cytoplasmic resistance and increased nucleus resistance and extracellular capacitance. Overall, the innovative construction of the eight-element CPE-equivalent circuit model further reflects that the pseudo-capacitance of the cell membrane and cell nucleus was increased in the AβO-induced group. This study conclusively revealed that AβOs induce cytotoxic effects by disrupting the resistance characteristics of unit membranes. The results further support that EIS is an effective technique for evaluating AβO-induced neuronal damage and microscopic electrical distinctions in the sub-microscopic structure of reactive cells. [ABSTRACT FROM AUTHOR]

Morphology‐controlled nanostructures are important functional materials in multidisciplinary research fields, such as sensing, imaging, catalysis, and energy harvesting. However, existing nanofabrication methods have limitations in terms of controllability, diversity, cost, and efficiency. Here, a novel nanofabrication approach is proposed to construct Au nanostructures with high controllability, cost‐efficiency, and high‐performance sensing and energy harvesting. The fabrication incorporates electric field‐assisted hydrothermal growth of zinc oxide nanorods (ZnO NRs) with two‐step gold electroplating. The ZnO NRs serve as a dissolvable template during the electroplating formation of gold nanostructures for eventually synthesizing pure gold nanostructures on electrodes. The synthesized gold nanostructures take unique composite shape of nanospheres (hundreds of nanometers) covered with tinier nanostructures (tens of nanometers) like floccules, grains, lamellas, or rods, which are highly controlled by regulating electroplating parameters. The gold composite nanostructures provide high‐performance sensing and energy harvesting, such as enhanced electrochemical sensing interface (electric double‐layer impedance decrease up to 97.1%), excellent surface‐enhanced Raman scattering (SERS enhancement factor up to 5×107$5 \times \left(10\right)^{7}$), and preferable visible–near‐infrared light harvesting (absorptivity near to 90%). For the first time, the application of tumor cell photothermal therapy with nanostructured electrodes and in situ bimodal monitoring of single‐cell impedance and SERS‐based molecular expression during therapy is demonstrated. [ABSTRACT FROM AUTHOR]

Background: Alveoli tend to collapse in patients with acute respiratory distress syndrome (ARDS). Endotracheal aspiration may increase alveolar collapse due to the loss of end-expiratory lung volume (EELV). We aimed to compare the loss of EELV after open and closed suction in patients with ARDS. Methods: This randomized crossover study included 20 patients receiving invasive mechanical ventilation for ARDS. Open and closed suction were applied in a random order. Lung impedance was measured using electric impedance tomography. The change in end-expiratory lung impedance (EELI) end of suction and at 1, 10, 20, and 30 min after suction, was used to represent the change in EELV. Arterial blood gas analyses and ventilatory parameters such as the plateau pressure (Pplat), driving pressure (Pdrive), and compliance of the respiratory system (CRS) were also recorded. Results: Less volume loss was noted after closed suction than after open suction (mean ΔEELI: -2661 ± 1937 vs. -4415 ± 2363; mean difference: -1753, 95% CI [-2662, -844], P = 0.001). EELI returned to baseline 10 min after closed suction but did not return to baseline even 30 min after open suction. After closed suction, the Pplat and Pdrive decreased while the CRS increased. Conversely, the Pplat and Pdrive increased while the CRS decreased after open suction. Conclusions: Endotracheal aspiration may result in alveolar collapse due to loss of EELV. Given that closed suction is associated with less volume loss at end-expiration without worsening ventilatory parameters, it should be chosen over open suction in patients with ARDS. [ABSTRACT FROM AUTHOR]

Recently, the favorable electrical properties of biomaterials have been acknowledged as crucial for various medical applications, including both bone healing and growth processes. This review will specifically concentrate on calcium phosphate (CaP)-based bioceramics, with a notable emphasis on hydroxyapatite (HA), among the diverse range of synthetic biomaterials. HA is currently the subject of extensive research in the medical field, particularly in dentistry and orthopedics. The existing literature encompasses numerous studies exploring the physical–chemical, mechanical, and biological properties of HA-based materials produced in various forms (i.e., powders, pellets, and/or thin films) using various physical and chemical vapor deposition techniques. In comparison, there is a relative scarcity of research on the electrical and dielectric properties of HA, which have been demonstrated to be essential for understanding dipole polarization and surface charge. It is noteworthy that these electrical and dielectric properties also offer valuable insights into the structure and functioning of biological tissues and cells. In this respect, electrical impedance studies on living tissues have been performed to assess the condition of cell membranes and estimate cell shape and size. The need to fill the gap and correlate the physical–chemical, mechanical, and biological characteristics with the electrical and dielectric properties could represent a step forward in providing new avenues for the development of the next-generation of high-performance HA-doped biomaterials for future top medical applications. Therefore, this review focuses on the electrical and dielectric properties of HA-based biomaterials, covering a range from powders and pellets to thin films, with a particular emphasis on the impact of the various dopants used. Therefore, it will be revealed that each dopant possesses unique properties capable of enhancing the overall characteristics of the produced structures. Considering that the electrical and dielectric properties of HA-based biomaterials have not been extensively explored thus far, the aim of this review is to compile and thoroughly discuss the latest research findings in the field, with special attention given to biomedical applications. [ABSTRACT FROM AUTHOR]

Piezoelectric cement-based composites could serve to monitor the strain state of structural elements or act as self-powered materials in structural health monitoring (SHM) applications. The incorporation of piezoelectric materials as an active phase within cement matrices has presented a highly attractive avenue until today. However, their application is challenged by the low electrical conductivity of the hydrated cement matrix. Gold nanoparticles (Au NPs) possess substantial potential for elevating the free electrical charge within the matrix, increasing its electrical conductivity between the Au NPs and the cement matrix, thereby enhancing the piezoelectric response of the composite. In this sense, the objective of this study is to investigate the effects of incorporating low concentrations of gold nanoparticles (Au NPs) (442 and 658 ppm) on the electrical and piezoelectric properties of cement-based composites. Additionally, this study considers the effects of such properties when the material is cured under a constant electric field. Electrical impedance spectroscopy was used to evaluate the polarization resistance and piezoresistive properties of the material. Additionally, open-circuit potential measurements were taken alongside the application of mechanical loads to assess the piezoelectric activity of the composites. The findings revealed a notable decrease in the composite's total electrical resistance, reaching a value of 1.5 ± 0.2 k Ω , almost four times lower than the reference specimens. In the realm of piezoelectricity, the piezoelectric voltage parameter g 33 exhibited a remarkable advancement, improving by a factor of 57 when compared to reference specimens. This significant enhancement can be attributed to both the concentration of Au NPs and the electrical curing process. In summary, the outcomes of this study underscore the feasibility of creating a highly electrically conductive cement-based matrix, using low concentrations of gold nanoparticles as electric charge carries, and indicate the possible piezoelectric behavior of the studied compposite. [ABSTRACT FROM AUTHOR]

The possibility of determining the elastic modules, viscosity coefficients, dielectric constant and electrical conductivity of a viscous conducting liquid using a piezoelectric resonator with a longitudinal electric field is shown. For the research, we chose a piezoelectric resonator made on an AT-cut quartz plate with round electrodes, operating with a shear acoustic mode at a frequency of about 4.4 MHz. The resonator was fixed to the bottom of a 30 mL liquid container. The samples of a mixture of glycerol and water with different viscosity and conductivity were used as test liquids. First, the frequency dependences of the real and imaginary parts of the electrical impedance of a free resonator were measured and, using the Mason electromechanical circuit, the elastic module, viscosity coefficient, piezoelectric constant and dielectric constant of the resonator material (quartz) were determined. Then, the container was filled with the test sample of a liquid mixture so that the resonator was completely covered with liquid, and the measurement of the frequency dependences of the real and imaginary parts of the electrical impedance of the loaded resonator was repeated. The dependences of the frequency of parallel and series resonances, as well as the maximum values of the electrical impedance and admittance on the conductivity of liquids for various viscosity values, were plotted. It was shown that these dependences can be used to unambiguously determine the viscosity and conductivity of the test liquid. Next, by fitting the theoretical frequency dependences of the real and imaginary parts of the electrical impedance of the resonator loaded with the liquid under study to the experimental dependences, the elastic module of the liquid and its dielectric constant were determined. [ABSTRACT FROM AUTHOR]

Background: Prone position (PP) and the positive end-expiratory pressure (PEEP)-induced lung recruitment maneuver (LRM) are both efficient in improving oxygenation and prognosis in patients with ARDS. The synergistic effect of PP combined with PEEP-induced LRM in patients with ARDS remains unclear. We aim to explore the effects of PP combined with PEEP-induced LRM on prognosis in patients with moderate to severe ARDS and the predicting role of lung recruitablity. Methods: Patients with moderate to severe ARDS were consecutively enrolled. The patients were prospectively assigned to either the intervention (PP with PEEP-induced LRM) or control groups (PP). The clinical outcomes, respiratory mechanics, and electric impedance tomography (EIT) monitoring results for the two groups were compared. Lung recruitablity (recruitment-to-inflation ratio: R/I) was measured during the PEEP-induced LRM procedure and was used for predicting the response to LRM. Results: Fifty-eight patients were included in the final analysis, among which 28 patients (48.2%) received PEEP-induced LRM combined with PP. PEEP-induced LRM enhanced the effect of PP by a significant improvement in oxygenation (∆PaO2/FiO2 75.8 mmHg vs. 4.75 mmHg, p < 0.001) and the compliance of respiratory system (∆Crs, 2 mL/cmH2O vs. −1 mL/cmH2O, p = 0.02) among ARDS patients. Based on the EIT measurement, PP combined with PEEP-induced LRM increased the ventilation distribution mainly in the dorsal region (5.0% vs. 2.0%, p = 0.015). The R/I ratio was measured in 28 subjects. The higher R/I ratio was related to greater oxygenation improvement after LRM (Pearson's r = 0.4; p = 0.034). Conclusions: In patients with moderate to severe ARDS, PEEP-induced LRM combined with PP can improve oxygenation and dorsal ventilation distribution. R/I can be useful to predict responses to LRM. [ABSTRACT FROM AUTHOR]

Cross-borehole electrical resistivity tomography (CHERT) technology has been implemented in field-scale CCS/CCUS (carbon capture and storage/carbon capture, utilization and storage) projects. It is highly desirable to investigate how to optimize the design of the ERT electrode arrays and corresponding working schemes for both laboratory experiments and field applications. A CHERT system was developed for laboratory experiments of CO2 geological storage applications. An optimization method was established for optimizing the structure of electrode arrays and corresponding working schemes. The developed CHERT system was calibrated systematically to determine the measurement range and accuracy of electrical impedance. Laboratory experiments were designed and implemented to validate the performance of the developed CHERT system. It has been illustrated that: (1) It is an essential step to optimize the structure of electrode arrays and corresponding working schemes of CHERT according to the real application background. The optimization method based on finite-element modelling provides an effective means for designing a field-scale CHERT system. (2) The quality of the images inverted from the CHERT data is highly dependent on the working schemes and specific modes, which is closely related to the size of the data sets used for the inversion. The AM-BN scheme is recommended due to the better uniformity of the resultant sensitivity field and application to larger borehole spacing. (3) Based on the calibration, the measurement range of the developed CHERT system can be determined as 100 Ω to 4.5 kΩ with an error limit of 1.5%. The maximum relative errors of the impedance magnitude and phase angle are 5.0% and 7.0%, respectively. Based on the test results the location of the CO2-bearing objects can be identified accurately. The shapes of the tested objects present distortion to some extent, but this can be alleviated by selecting working modes with a larger size of data set. [ABSTRACT FROM AUTHOR]

Doctors or health laboratory workers usually carry out manual blood examinations, who cell morphology parameters by eye. Electrical impedance spectroscopy has been proposed to assist doctors in examining blood damage. The effect of storage on blood cells will be evaluated using an electrical impedance measurement system on blood cells. The results of electrical impedance measurements will be correlated with the quality and quantity of blood cells, namely the mean corpuscular hemoglobin concentration (MCHC) value. Three bags of complete blood cell packages (from different donors) and 1 bag of red blood cell packages were used as blood samples. All blood samples using citrate phosphate dextrose adenine (CPDA) anticoagulant were obtained from the Indonesian Red Cross, Malang City Branch. Electrical impedance and cell-count measurements were performed on Day 0 (before being put into the refrigerator) and on Days 2, 4, 7, 10, 17, 21 and 28 after being placed in the fridge. Electrical impedance was measured using Bio-Impedance Spectroscopic Data Acquisition (BISDAQ). As the duration of storage increases, the MCHC value tends to decrease. The total impedance tends to decrease with increasing storage duration; the total impedance on Day 28 shows the lowest value. In general, the resistance value of the solution is correlated with the MCHC value of the blood cells. The escape of some material in the cell to the solution outside the cell results in a decrease in the resistance properties of the solution, according to the study's results. The total electrical impedance decreases with increasing storage duration. Storage duration affects the quality and quantity of blood cells. The MCHC value of blood cells decreased with increasing storage duration. The value of MCHC is strongly correlated with the value of the external solution resistance of the cell. [ABSTRACT FROM AUTHOR]

The structural parameters, optical properties, and dielectric constants at a frequency (f) range of 0.1–20 MHz, and temperature (T) range of 300–400 K of hydrothermally synthesized M/SnO 2 nanocomposites (for simplicity M denotes oxides of Al, Ni, or Mn) were compared. Rietveld refined X-ray powder diffraction (XRD) analysis demonstrated the formation of hexagonal, cubic, or spinel crystal structures of Al 2 O 3 , NiO, or Mn 3 O 4 phases, respectively, besides the tetragonal rutile crystal structure of SnO 2. The impact of Al addition on the optical band gap of SnO 2 is negligible while it decreased or increased by incorporation of Ni or Mn, respectively. The residual lattice dielectric constant of SnO 2 was increased, while the real part of the dielectric constant and the ac conductivity of SnO 2 were decreased by M incorporation. The dielectric parameters are remarkably affected by selected M, T, and f values and their changes agree with the Maxwell-Wagner model. The Q-factor of SnO 2 was increased by M addition while decreased with increasing T. The Ni/SnO 2 obeys the hole conduction at T ≤ 330 K, while Mn/SnO 2 and Ni/SnO 2 obey the electronic conduction at T > 330 K. The binding energy is independent of the chosen T for SnO 2 , whereas it sharply increases for Ni/SnO 2 and slightly decreases for Al/SnO 2 and Mn/SnO 2. The F-factor of SnO 2 was slightly decreased by M addition, but it was increased with T for SnO 2 , Al/SnO 2 , and Mn/SnO 2 while was decreased for Ni/SnO 2. The Cole-Cole plots for M/SnO 2 composites were analyzed, and the components of the equivalent circuit were determined. The electrical impedance, resistance of grains, resistance of grain boundaries, and equivalent resistance of SnO 2 were increased by M incorporation, whereas equivalent capacitance was decreased. The findings recommend the SnO 2 -based nanocomposites for applications in optoelectronics, lithium batteries, supercapacitors, and solar cell devices. [ABSTRACT FROM AUTHOR]

Implantable cell replacement therapies promise to completely restore the function of neural structures, possibly changing how we currently perceive the onset of neurodegenerative diseases. One of the major clinical hurdles for the routine implementation of stem cell therapies is poor cell retention and survival, demanding the need to better understand these mechanisms while providing precise and scalable approaches to monitor these cell-based therapies in both pre-clinical and clinical scenarios. This poses significant multidisciplinary challenges regarding planning, defining the methodology and requirements, prototyping and different stages of testing. Aiming toward an optogenetic neural stem cell implant controlled by a smart wireless electronic frontend, we show how an iterative development methodology coupled with a modular design philosophy can mitigate some of these challenges. In this study, we present a miniaturized, wireless-controlled, modular multisensor platform with fully interfaced electronics featuring three different modules: an impedance analyzer, a potentiostat and an optical stimulator. We show the application of the platform for electrical impedance spectroscopy-based cell monitoring, optical stimulation to induce dopamine release from optogenetically modified neurons and a potentiostat for cyclic voltammetry and amperometric detection of dopamine release. The multisensor platform is designed to be used as an opto-electric headstage for future in vivo animal experiments. [ABSTRACT FROM AUTHOR]

In a seismic context, it is fundamental to deploy distributed sensor networks for Structural Health Monitoring (SHM). Indeed, regularly gathering data from a structure/infrastructure gives insight on the structural health status, and Artificial Intelligence (AI) technologies can help in exploiting this information to generate early warnings useful for decision-making purposes. With a perspective of developing a remote monitoring platform for the built environment in a seismic context, the authors tested self-sensing concrete beams in loading tests, focusing on the measured electrical impedance. The formed cracks were objectively assessed through a vision-based system. Also, a comparative analysis of AI-based and statistical prediction methods, including Prophet, ARIMA, and SARIMAX, was conducted for predicting electrical impedance. Results show that the real part of electrical impedance is highly correlated with the applied load (Pearson's correlation coefficient > 0.9); hence, the piezoresistive ability of the manufactured specimens has been confirmed. Concerning prediction methods, the superiority of the Prophet model over statistical techniques was demonstrated (Mean Absolute Percentage Error, MAPE < 1.00%). Thus, the exploitation of electrical impedance sensors, vision-based systems, and AI technologies can be significant to enhance SHM and maintenance needs prediction in the built environment. [ABSTRACT FROM AUTHOR]

This paper introduces a sensitivity matrix decomposition regularization (SMDR) method for electric impedance tomography (EIT). Using k-means clustering, the EIT-reconstructed image can be divided into four clusters, derived based on image features, representing posterior information. The sensitivity matrix is then decomposed into distinct work areas based on these clusters. The elimination of smooth edge effects is achieved through differentiation of the images from the decomposed sensitivity matrix and further post-processing reliant on image features. The algorithm ensures low computational complexity and avoids introducing extra parameters. Numerical simulations and experimental data verification highlight the effectiveness of SMDR. The proposed SMDR algorithm demonstrates higher accuracy and robustness compared to the typical Tikhonov regularization and the iterative penalty term-based regularization method (with an improvement of up to 0.1156 in correlation coefficient). Moreover, SMDR achieves a harmonious balance between image fidelity and sparsity, effectively addressing practical application requirements. [ABSTRACT FROM AUTHOR]

Neodymium Indium sulphide (Nd4In5S13) photoactive electrode was produced by spin‐coating for photoelectrochemical cell. The photoactive electrode is analysed for its crystalline, structural and elements makeup in addition to its optical and electrical responses. A 56 nm sized orthorhombic crystallite was found and geometrical compact structures were observed. The presence of chief elements with core levels of In3d, Nd4d and S2p were detected. The bandgap energy was found to be 4.1 eV. Electrochemical investigations were performed to evaluate the photoactive efficiency of the electrode. Photo‐cyclic voltammetry present a specific capacitance under illumination to be 570 Fg−1, as contrasting to 481 Fg−1 when in dark. A photocurrent density of 282 mA cm−2 was obtained from photo‐linear sweep voltammetry. It had also been discovered that the transient chronoamperometry provided a photocurrent density of 46.1 mA cm−2. Whereas electrical impedance spectroscopy presented internal resistance (Rs) to be 232 Ω. All scan rates show an increase in the specific capacitance of photo‐electrode when illuminated. The research created an effective photo‐electrode for renewable energy structures. It can be posited that the study presented a pragmatic photoelectrode, which had the potential to be employed in sustainable energy frameworks, including but not limited to photovoltaics, supercapacitors, and photoelectrochemical solar cells. [ABSTRACT FROM AUTHOR]