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To enhance our understanding of electroporation and optimize the pulses used within the frequency range of 1 kHz to 100 MHz, with the aim of minimizing side effects such as muscle contraction, we introduce a novel electrical model, structured as a 2D representation employing exclusively lumped elements. This model adeptly encapsulates the intricate dynamics of living cells' impedance variation. A distinguishing attribute of the proposed model lies in its capacity to decipher the distribution of transmembrane potential across various orientations within living cells. This aspect bears critical importance, particularly in contexts such as electroporation and cellular stimulation, where precise knowledge of potential gradients is pivotal. Furthermore, the augmentation of the proposed electrical model with the Hodgkin-Huxley (HH) model introduces an additional dimension. This integration augments the model's capabilities, specifically enabling the exploration of muscle cell stimulation and the generation of action potentials. This broader scope enhances the model's utility, facilitating comprehensive investigations into intricate cellular behaviors under the influence of external electric fields. In our research, we've introduced an enhanced electrical model for living cells. This model simplifies cell behavior using only basic electrical components like resistors and capacitors. It's designed to mimic the real electrical properties of cells, particularly the cell membrane, which can change in response to electricity at different frequencies, ranging from 1 kHz to 100 MHz. This frequency range is essential for studying processes like electroporation, a technique used in various medical applications. Our model is represented in a two-dimensional structure, making it a handy tool for identifying transmembrane potential distributions, a critical factor in electroporation procedures. This means we can better understand how cells react to electrical impulses, which is crucial for improving electroporation techniques. Additionally, we've extended our model to include muscle cells by incorporating the Hodgkin-Huxley model, a well-established model for understanding electrical behavior in muscle cells. This allows us to study how muscles contract when exposed to different electrical pulses, a common side effect of electroporation procedures. By examining various pulse characteristics, we can determine which ones are best for minimizing muscle contractions during electroporation. In summary, our research has led to the development of a versatile electrical model for living cells. It not only helps us understand how cells respond to electricity in the context of electroporation but also provides insights into muscle contractions and how to optimize electrical pulses for medical treatments. [ABSTRACT FROM AUTHOR]

The aim of this article is to determine a similar point to the Lift-Off intersection point (LOI) obtained from a geometric configuration of a Pulsed Eddy Current (PEC) sensor. This configuration enables easy determination of the LOI point through a single measurement, thus avoiding measurement noise. The sensor consists of an external excitation coil and two internal probes that overlap and have similar characteristics for reception. The similar point LOI is determined by the intersection of the signals from the transient response of the sensor's internal probes. Importantly, this point is independent of lift-off variation. Moreover, the amplitude and time measurement of this point vary with the variation of the physical and geometric properties of the sample. To assess the effectiveness of this similar point, a numerical code based on electromagnetic phenomena was developed. This code investigates the impact of thickness and electrical conductivity of metal sheets on the response of the PEC sensor, both with and without a ferrite core at this point. Additionally, a practical sensor prototype was constructed to validate the results obtained from the numerical model. The obtained results demonstrated a strong correlation between the numerical and experimental outcomes, thus confirming the effectiveness of the proposed technique. [ABSTRACT FROM AUTHOR]

The conventional electromagnetic interference (EMI) shielding materials are being gradually replaced by a new generation of supported conducting polymer composites (CPC) films due to their many advantages. This work presents a contribution on the effects of silane surface–modified flexible polypyrrole-silver nanocomposite films on the electromagnetic interference shielding effectiveness (EMI-SE). Thus, the UV-polymerization was used to in-situ deposit the PPy-Ag on the biaxial oriented polyethylene terephthalate (BOPET) flexible substrates whose surfaces were treated by 3-aminopropyltrimethoxysilane (APTMS). X-ray Photoelectron Spectroscopy (XPS) analyzes confirmed the APTMS grafting procedure. Structural, morphological, thermal, and electrical characteristics of the prepared films were correlated to the effect of substrate surface treatment. Thereafter, EMI-SE measurements of the elaborated films were carried out as per ASTM D4935 standard for a wide frequency band extending from 50 MHz to 18 GHz. The obtained results confirmed that the APTMS-treated BOPET film exhibit higher EMI shielding performance and better electrical characteristics compared to the untreated film. In fact, a 32% enhancement of EMI-SE was noted for the treated films compared to the untreated ones. Overall, these results put forward the role played by the surface treatment in strengthening the position of flexible PPy-Ag supported films as high-performance materials in electronic devices and electromagnetic interference shielding applications. [ABSTRACT FROM AUTHOR]

As the information age matures, a biometric identification technology will be at the heart of computer interaction with humans and the biosphere in which they reside. Hence, the reliable information security mechanisms are needed to combat the rising magnitude of identity theft. While cryptography is a powerful tool to achieve information security, one of the main challenges in cryptosystems is to maintain the secrecy of the cryptographic keys. Template protection techniques prevent stored reference data from revealing private biometric information and enhance the security of biometric systems against attacks such as identity theft and cross matching. A critical issue in biometric systems is to protect the template of a user which is typically stored in a database or a smart card. The fuzzy vault construct is a challenging biometric cryptosystem that secures both the secret key and the biometric template by binding them within a cryptographic framework. The helper data itself do not leak any information about the biometric template, yet contain sufficient information to align the template and query biometric accurately. This paper reviews the state of the art biometrics Cryptosystems from the Point of Challenging Designs Strategies. [ABSTRACT FROM AUTHOR]

This paper proposes a contactless method for the identification of the electrical conductivity tensor of a carbon fiber composite materials plate using a rotating magnetic field and multi-coil eddy current sensor. This sensor consists of identical rectangular multi-coil, excited by two-phase sinusoidal current source in order to generate a rotating magnetic field and to avoid the mechanical rotation of the sensor. The fibers orientations, the longitudinal and transverse conductivities in each ply of carbon fiber composite material plate were directly determined with analysis of the impedance variation of each coil as function of its angular position. The inversion process is based on the use of artificial neural networks. The direct calculation associated with artificial neural networks makes use of 3D time-harmonic finite element method based on the A, V–A formulation. [ABSTRACT FROM AUTHOR]

As the information age matures, a biometric identification technology will be at the heart of computer interaction with humans and the biosphere in which they reside. Hence, the reliable information security mechanisms are needed to combat the rising magnitude of identity theft. While cryptography is a powerful tool to achieve information security, one of the main challenges in cryptosystems is to maintain the secrecy of the cryptographic keys. Template protection techniques prevent stored reference data from revealing private biometric information and enhance the security of biometric systems against attacks such as identity theft and cross matching. A critical issue in biometric systems is to protect the template of a user which is typically stored in a database or a smart card. The fuzzy vault construct is a challenging biometric cryptosystem that secures both the secret key and the biometric template by binding them within a cryptographic framework. The helper data itself do not leak any information about the biometric template, yet contain sufficient information to align the template and query biometric accurately. This paper reviews the state of the art biometrics Cryptosystems from the Point of Challenging Designs Strategies. [ABSTRACT FROM AUTHOR]

Cancer remains a global health challenge, necessitating effective treatments with fewer side effects. Traditional methods such as chemotherapy and surgery often have complications. Pulsed electric fields and electroporation have emerged as promising approaches to mitigate these challenges. This study presents a comprehensive overview of electroporation as an innovative tool in cancer therapy, encompassing critical elements such as pulse generators and delivery devices. Furthermore, it introduces a simplified reversible electroporation model grounded in the Hodgkin-Huxley model. This model ensures resting potential stability by regulating ionic currents. When membrane charges reach the electroporation threshold, the model swiftly increases the fraction of open pores, resulting in a rapid rise in electroporation current. Conversely, as the transmembrane potential drops below the threshold, the model gradually reduces the fraction of open pores, leading to a gradual decline in electroporation current, indicating pore resealing. This model contributes to easier modeling and implementation of reversible electroporation dynamics, providing a valuable tool for further exploration of electroporation for cancer therapy., (Copyright 2024, Mary Ann Liebert, Inc., publishers.)