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A recent study from Brawijaya University explores the use of the dielectric method to analyze diabetes mellitus screening methods based on the electrical properties of cells. The research involved 90 mice and found that the dielectric constant values correlated with different levels of diabetes and specific cell damage types. The study concluded that the dielectric method could be an alternative screening method for diabetes mellitus based on the electrical properties of cells. [Extracted from the article]

• Single-phase BTZSHC high-entropy ceramics were successfully prepared via the sol-gel method at relative low temperature. • The single-phase formation mechanism of the as-prepared high-entropy ceramics is attributed to thermodynamic factors. • The sluggish diffusion effect ensures the thermal stability of high-entropy systems. • The relaxor behavior of the BTZSHC high-entropy ceramics is caused by the thermal evolution of the PUs in the lattice. Single-phase Ba(Ti 0.2 Zr 0.2 Sn 0.2 Hf 0.2 Ce 0.2)O 3 (BTZSHC) high-entropy ceramics (HECs) with the perovskite structure were successfully prepared via the sol-gel method. The results reveal that the as-prepared ceramics exhibit a single cubic phase belonging to the P m 3 ¯ m space group. The high entropy is the driving force of the formation of single-phase ceramics. A larger entropy (Δ S mix) and a negative enthalpy (Δ H mix) are conducive to the formation of single-phase compounds. Herein, Δ S mix = 0.323 R mole–1 and Δ H mix = −43.88 kJ/mol. The sluggish-diffusion effect ensures the thermal stability of high-entropy systems. Dielectric measurements reveal that the as-prepared BTZSHC high-entropy ceramics are relaxor ferroelectrics, and the degree of relaxor (γ) is 1.9. The relaxor behavior of the as-prepared ceramics can be ascribed to the relaxation and thermal evolution of their polar units (PUs). The findings of this work provide a theoretical basis and technical support for the preparation of single-phase high-entropy ceramics. [ABSTRACT FROM AUTHOR]

This article discusses a newly launched clinical trial, NCT06512129, which aims to investigate the influence of extracellular water on volume status in adult sepsis patients with hemodynamic instability. The trial seeks to determine if measuring extracellular water can contribute to the description of hemodynamic instability in these patients. The study will involve adult sepsis patients admitted to intensive care, who will receive standard care along with the measurement of extracellular water. The trial is currently in the recruitment phase and is expected to be completed by December 2026. [Extracted from the article]

A patent has been issued to Becton Dickinson and Company for a reactance and capacitance sensing platform that can detect microorganisms in a biological sample. The invention aims to achieve faster detection of bacteria by using impedance measurements to monitor changes in the ionic composition of the sample over time. The system has increased sensitivity to microorganism growth and can detect changes in both the composition of charged molecules and the number of microorganisms. The method can be used with sample volumes ranging from microliters to milliliters and offers faster scan times and reduced time-to-detection. [Extracted from the article]

This article discusses the importance of density profiling in asphalt pavement construction and the use of ground penetrating radar (GPR) as a nondestructive method for measuring pavement density. The current methods of density measurement, such as core drilling and nuclear gauges, have limitations and associated costs. The article highlights the collaborative efforts of 14 state departments of transportation and the Federal Highway Administration (FHWA) to test and standardize GPR technology. The FHWA's NDE Laboratory is conducting research to evaluate the performance and optimize the use of GPR for density profiling. The article emphasizes the value of collaborative research and the potential for GPR to revolutionize pavement compaction assessment. [Extracted from the article]

Recent IWCS conference publications from the authors have evaluated the Cavity Perturbation Technique for the measurements of dielectric constant of Ethernet cable dielectrics. Marked changes in both dielectric properties and transmission performance of Ethernet cable and its dielectrics as a consequence of thermal variation have been noted and reported.Thermal variations in twisted pair Ethernet cables are commonly associated with Power over Ethernet delivery as well as changes in the cabling operating environments.To date, only changes in the transmission parameters of the Ethernet cables and the real part of the dielectric permittivity have been reported. This paper reviews previous work and reports further progress in the dielectric measurements.Firstly, the dielectric properties of Fluorinated Ethylene Propylene (FEP)and High-Density Polyethylene (HDPE)used in Ethernet cabling were examined at an elevated room temperature to compare their dielectric constant at 1GHz, 2.4GHz and 5GHz. After that, a continuous 30-day heating at ~65°C without cooling was carried out on the FEP to observe the effect of prolonged heating on its dielectric constant at 2. 4GHz and 5GHz. And lastly, FEP was thermally cycled between the room temperature and ~65°C to study the effect of intermittent and prolonged heat cycling on its dielectric constant (εr) and loss tangent (tanδ). The εr of FEP was found to be lower when compared to that of HDPE at room temperature.Furthermore, the evaluation of the εr of FEP at 5GHz based on constant heating of ~65°C suggests that the εr may initially decrease but later increase permanently based on prolonged heating.Whereas, at 2.4GHz,the εr of FEP may likely decrease progressively as a consequence of prolonged heating. However, due to thermal cycling of the FEP at 2.4GHz,the εr decreased due to the effect of temperature at 60°C but increased based on the cooling at 25°C. Progressive increase in the tanδ of the FEP was also observed during the heating and cooling cycles. [ABSTRACT FROM AUTHOR]

A new study conducted by Merck & Company in West Point, Pennsylvania, explores the use of in situ process analytical technology (PAT) for real-time analysis of live-virus vaccine production. The study focuses on monitoring viable cell density (VCD) and cell viability (CV), which are important indicators of cell culture processes in biopharmaceutical production. Traditional methods for monitoring VCD and CV are labor-intensive and prone to variability. The study proposes the use of in situ dielectric spectroscopy as a PAT tool, which involves continuous real-time analysis of VCD and CV. The results show that this approach successfully predicts VCD and CV during live virus-based vaccine production, offering improved process understanding. This research is the first to report the successful use of in situ dielectric spectroscopy with multivariate analysis for real-time monitoring in live-virus vaccine production. [Extracted from the article]

Researchers from the Sathyabama Institute of Science and Technology in Chennai, India have conducted a study on the crystal formation and properties of l-histidine hydrochloride hydrate (LHHCLH) crystals. The study used various characterization techniques such as X-ray crystallography, NMR spectroscopy, UV-Vis spectroscopy, second harmonic generation (SHG) test, dielectric, and electrical conductivity studies. The results showed that the LHHCLH crystals had enhanced nonlinear optical properties and generated a significant amount of second harmonic generation signal. The study also analyzed the dielectric properties and AC/DC conductivities of the crystals. The research concluded that the activation energies for AC and DC conduction processes were 2.03 and 1.91 eV, respectively. This research has been peer-reviewed and may have potential applications in optoelectronics. [Extracted from the article]

Keywords: Food Products; Food Research EN Food Products Food Research 27 27 1 07/10/23 20230713 NES 230713 2023 JUL 13 (NewsRx) -- By a News Reporter-Staff News Editor at Food Weekly News -- Current study results on food research have been published. Keywords for this news article include: University of Cagliari, Cagliari, Italy, Europe, Food Products, Food Research. [Extracted from the article]

Keywords: Cardiology; Health and Medicine; Hyperventilation; Respiration Disorders; Respiratory Tract Diseases and Conditions EN Cardiology Health and Medicine Hyperventilation Respiration Disorders Respiratory Tract Diseases and Conditions 973 973 1 04/17/23 20230421 NES 230421 2023 APR 17 (NewsRx) -- By a News Reporter-Staff News Editor at Respiratory Therapeutics Week -- Current study results on hyperventilation have been published. Cardiology, Health and Medicine, Hyperventilation, Respiration Disorders, Respiratory Tract Diseases and Conditions. [Extracted from the article]

We present PyOECP, a Python-based flexible open-source software for estimating and modeling the complex permittivity obtained from the open-ended coaxial probe (OECP) technique. The transformation of the measured reflection coefficient to complex permittivity is performed based on three different methods. The software library contains the dielectric spectra of common reference liquids, which can be used to transform the reflection coefficient into the dielectric spectra. Several Python routines that are commonly employed (e.g., SciPy and NumPy) in the field of science and engineering are required only so that the users can alter the software structure depending on their needs. The modeling algorithm exploits the Markov Chain Monte Carlo method for the data regression. The discrete relaxation models can be built by a proper combination of well-known relaxation models. In addition to these models, electrode polarization, a typical measurement artifact for interpreting dielectric spectra, can be incorporated into the modeling algorithm. A continuous relaxation model, which solves the Fredholm integral equation of the first kind (a mathematically ill-posed problem), is also included. This open-source software enables users to freely adjust the physical parameters to obtain physical insight into their materials under test and will be consistently updated for more accurate measurement and interpretation of dielectric spectra in an automated manner. This work describes the theoretical and mathematical background of the software, lays out the workflow, and validates the software functionality based on both synthetic and empirical data included in the software. Program title: PyOECP 0.5 CPC Library link to program files: https://doi.org/10.17632/vsh6vb9cbv.1 Developer's repository link: https://github.com/tyoon124 Code Ocean capsule: https://codeocean.com/capsule/89645681 Licensing provisions: BSD-3 Clause License Programming language: Python3 External routines: Numpy, Scipy, and Matplotlib Nature of problem: Estimate and interpret the frequency-dependent (complex) permittivity in fluid(s) and their mixtures based on the reflection coefficients obtained from the open-ended coaxial probe (OECP) technique. The obtained dielectric spectra can be useful for understanding the relaxation processes in an arbitrary fluid. Solution method: The reflection coefficient data is obtained as a text format from a Vector Network Analyzer (VNA). This text data is parsed into a Numpy array. Three different modules (Stuchly, Marsland, and Komarov) can be used to transform the parsed reflection coefficient data into complex permittivity as a function of the measurement frequency. The resultant dielectric spectra can be dissected and interpreted by fitting either discrete relaxation model(s) based on the Markov Chain Monte Carlo algorithm or a continuous relaxation model by applying the Zasetsky-Buchner method. [ABSTRACT FROM AUTHOR]

This paper investigates the confinement and quality (Q) factors of the dielectric mode, exterior surface plasmonic mode, and interior surface plasmonic mode in a metal-nanolayer-coated silica microtoroid. It is found that the confinement of these modes relies mainly on the real part of the coating-metal permittivity, and a smaller negative real part produces a lower effective potential barrier which plays distinct roles in these three types of modes. For the exterior plasmonic mode, a lower potential leads to a better confinement and thus lower radiation losses, while for the interior plasmonic mode and the dielectric mode, a higher potential can play a very positive role in suppressing the radiation losses. The metal absorption loss, as expected, is directly related to the imaginary part of the metal permittivity and the energy fraction of the mode in the metal layer, and the latter depends on the confinement or, namely, the effective potential barrier induced by the metal nanolayer. We also compare the plasmonic modes in the coated microcavity and the dielectric modes in the uncoated microcavity at different cavity sizes. An interesting finding is that when the cavity is small enough, which is highly desirable for compact photonic devices, the Q factors of the plasmonic modes even exceed significantly that of the uncoated dielectric modes. [ABSTRACT FROM AUTHOR]

The effect of (Ba0.6Sr0.4)TiO3(BST) addition on dielectric properties of CaCu3Ti4O12 (CCTO) ceramic was investigated. Ceramic samples with the chemical formula (1–x)CaCu3Ti4O12 +x(Ba0.6, Sr0.4)TiO3 (x=0, 0.05, 0.1, and 0.2) were synthesized from high purity oxide powders by the conventional solid-state synthesis method. X-ray diffraction (XRD) analysis showed the existence of BST as a secondary phase alongside CCTO. Scanning electron microscopy (SEM) investigation showed a slight decrease in grain size of doped CCTO samples. Density measurements showed that porosity content increased with increasing BST addition indicating low densification due to high melting point secondary phase addition. Dielectric constant of undoped CCTO (x=0) showed lack of stability with frequency which dropped drastically between 104 and 105 Hz and accompanied by high dielectric loss. Addition of BST into CCTO caused the dielectric constant to slightly decrease but improved stability with frequency compared to the undoped sample. The decrease in dielectric constant of doped CCTO samples was suggested to be partly due to the decrease in average grain size and increase in porosity with BST addition. Nevertheless, a high value of dielectric constant was still maintained around ∼104 range for all doped samples. The dielectric loss (tanδ) of all BST-doped samples was lower than that of pure CCTO sample at the frequency range of 103 to 105 Hz probably due to the increase of grains boundary resistivity. The activation energy of grains boundary (E gb) showed higher values as compared to the activation energy of grains (E g) for all samples and conforms to the internal barrier layer capacitor (IBLC) model. [ABSTRACT FROM AUTHOR]

CaCu3–x Fe x Ti4O12 (x=0, 0.015, 0.03, 0.045, 0.06) ceramics were synthesized by sol–gel method. The electrical conduction and dielectric measurements show that the doping of a very small amount of Fe3+ ions greatly reduces the low-frequency dielectric constants and leakage, and enhances grain resistivity. For the doped samples, the appearance of the strong low-frequency peaks in the spectra of dielectric loss confirms that the doping of Fe3+ ions induces the contact-electrode effect on ceramic surface. These great changes of electrical properties may originate from the reduced amount of oxygen vacancies by doping Fe3+. [ABSTRACT FROM AUTHOR]

A study of the effects of absorption on the nonlinear process of parametric down-conversion is presented. Absorption within the nonlinear medium is accounted for by employing the framework of macroscopic QED and the Green tensor quantization of the electromagnetic field. An effective interaction Hamiltonian, which describes the nonlinear interaction of the electric field and the linear noise polarization field, is used to derive the quantum state of the light leaving a nonlinear crystal. The signal and idler modes of this quantum state are found to be a superposition of the electric and noise polarization fields. Using this state, the expression for the coincident count rates for both type-I and type-II down-conversion are found. The nonlinear interaction with the noise polarization field was shown to cause an increase in the rate on the order of 10-12 for absorption of 10% per centimeter. This astonishingly small effect is found to be negligible compared to the decay caused by linear absorption of the propagating modes. From the expressions for the biphoton amplitude, it can be seen that the maximally entangled states can still be produced even in the presence of strong absorption. [ABSTRACT FROM AUTHOR]

The effects of B2O3 addition, as a sintering agent, on the sintering behavior, microstructure and dielectric properties of CaMgSi2O6 ceramic have been investigated. The CaO-MgO-B2O3-SiO2 glassy phase came forth by adding B2O3 into CaO-MgO-SiO2 ceramic powders, and it was advantageous to lower the synthesis temperature of CaMgSi2O6 crystalline phase. Moreover, the emergence of CaO-MgO-B2O3-SiO2 glass phase could effectively lower the sintering temperature of CaMgSi2O6 ceramic and promote the CaMgSi2O6 grains growing. With 6 wt pct B2O3 addition, the densification temperature of CaMgSi2O6 ceramic could be effectively reduced from 1300 to 1100°C, and the dielectric constant (ɛr) and dielectric loss (tanδ) were: ɛr=7.61 and tanδ=7.4×10−4 (1 MHz). [Copyright &y& Elsevier]

Abstract: A novel finite-difference time-domain (FDTD) method with recursive relationships among operators, developed for magnetized dispersive medium, is named shift operator FDTD (SO-FDTD) method. In this paper, the dielectric property of magnetized dispersive media is written as rational polynomial function, the relationship between D and E is deduced in time-domain. The high accuracy and efficiency of this method is verified by calculating the reflection and transmission coefficient of electromagnetic waves through a collisional plasma slab. As the electron density in plasma distributes as Epstein formula, the effect of the gradient coefficient σ and plasma thickness on the reflection coefficient is calculated. The results show that with different σ, the distribution between the reflection coefficient and the incidence frequency is same; but there is certain difference within some specific frequency range. And there are fewer effects of different thicknesses on the reflection coefficient under different conditions. [Copyright &y& Elsevier]

Purpose ? The aim of this paper is to calculate the impedance of a loop antenna, etched on a dielectric substrate, over a wide frequency band using finite element method (FEM). Design/methodology/approach ? The electromagnetic analysis of the global structure is performed with a full wave finite element formulation. In this work, two methods for the calculation of the impedance of the antenna are presented: receiving and transmitting mode. The results obtained are compared with boundary element method (BEM). Findings ? The paper finds that from the FEM analysis an equivalent circuit of a rectenna was obtained over a wide frequency band. A good agreement was obtained with a BEM approach in the case of an air-like substrate. A dielectric substrate was considered. Such a configuration is more difficult to deal with BEM and makes the FEM attractive. Practical implications ? The equivalent circuit allows a global circuit simulation of the whole rectenna (antenna, rectifying diodes and load). This simulation can be achieved using spice simulator for example. Originality/value ? This paper shows the potentiality of the FEM to simulate an antenna over a broad band frequency. Two methods for the calculation of the impedance of the antenna are presented. It is addressed to R&D designers in the microwave area. [ABSTRACT FROM AUTHOR]

The (Bi0.9Ho0.1)3.999Ti2.997V0.003O12 (BHTV) films have been prepared on Pt/Ti/SiO2/Si substrates by solgel method. The microstructure and ferroelectric properties of the BHTV films were investigated. The BHTV films show a single phase of Bi-layered Aurivillius structure and dense microstructure. The Ho3+/V5+ co-substitution can effectively improve the ferroelectric properties. The BHTV film exhibits good ferroelectric properties with 2P r of 47.6°C/cm2, 2E c of 265 kV/cm (at applied field of 420 kV/cm), dielectric constant of 305, dielectric loss of 0.031 (at 1 MHz), good insulting behavior, as well as the fatigue-free behavior. [Copyright &y& Elsevier]

The article discusses the factors that need to consider in the maintenance assessment of transformers. Topics mentioned include the problems that high moisture in the transformer insulation may create, the reasons for the increase in water content in transformers, and the accuracy of a dielectric frequency response diagnostic test.

The article evaluates a series of insulation resistance testers such as MIT525, MIT1025 and MIT1525 offered by Megger.

The article focuses on the tuneable microwave cavity sensor developed at University of Oxford Department of Physics in Great Britain which can be used for fluid monitoring through its capacity to detect the changes in the dielectric properties of the samples.

Introduces several laboratory equipment. Specifications of the thermocouple feedthru system; Usability of the Stellar Stereotaxic Instrument for animal brain surgery; Features of the MDC Series 20 Cure Monitor, high-performance dielectric measurement system.