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The osmotic pressure of dilute electrolyte solutions containing charged macro-ions as well as counterions can be computed directly from the particle distribution via the well-known cell model. Originally derived within the Poisson-Boltzmann mean-field approximation, the cell model considers a single macro-ion centered into a cell, together with counterions needed to neutralize the total cell charge, while it neglects the phenomena due to macro-ion correlations. While extensively applied in coarse-grained Monte Carlo (MC) simulations of continuum solvent systems, the cell model, in its original formulation, neglects the macro-ion shape anisotropy and details of the surface charge distribution. In this paper, by comparing one-body and two-body coarse-grained MC simulations, we first establish an upper limit for the assumption of neglecting correlations between macro-ions, and second, we validate the approximation of using a non-spherical macro-ion. Next, we extend the cell model to all-atom molecular dynamics simulations and show that protein concentration-dependent osmotic pressures can be obtained by confining counterions in a virtual, spherical subspace defining the protein number density. Finally, we show the possibility of using specific interaction parameters for the protein-ion and ion-ion interactions, enabling studies of protein concentration-dependent ion-specific effects using merely a single protein molecule.

In this paper, an isolated single-ended primary-inductive converter (ISEPIC) with a softswitching cell for implementing features of zero-voltage switching (ZVS) and zero-current switching (ZCS) is proposed. The ISEPIC has the following advantages: (1) By changing the inductor element of the ISEPIC into a transformer element, the features of electrical isolation can be achieved. (2) By incorporating a soft-switching cell, the power switches (MOSFETs) of the ISEPIC can achieve ZVS and ZCS features during turn-on conditions. Therefore, the power losses of the power switches can be reduced during the turn-on transient, and the overall efficiency of the ISEPIC can be increased significantly. Finally, a prototype of the ISEPIC with a soft-switching cell is built. Experimental results are presented to verify the performance and feasibility of the proposed ISEPIC for implementing features of ZVS and ZCS. [ABSTRACT FROM AUTHOR]

Grid cells and place cells are important neurons in the animal brain. The information transmission between them provides the basis for the spatial representation and navigation of animals and also provides reference for the research on the autonomous navigation mechanism of intelligent agents. Grid cells are important information source of place cells. The supervised learning and unsupervised learning models can be used to simulate the generation of place cells from grid cell inputs. However, the existing models preset the firing characteristics of grid cell. In this paper, we propose a united generation model of grid cells and place cells. First, the visual place cells with nonuniform distribution generate the visual grid cells with regional firing field through feedforward network. Second, the visual grid cells and the self-motion information generate the united grid cells whose firing fields extend to the whole space through genetic algorithm. Finally, the visual place cells and the united grid cells generate the united place cells with uniform distribution through supervised fuzzy adaptive resonance theory (ART) network. Simulation results show that this model has stronger environmental adaptability and can provide reference for the research on spatial representation model and brain-inspired navigation mechanism of intelligent agents under the condition of nonuniform environmental information. [ABSTRACT FROM AUTHOR]

Fringe‐Field Switch (FFS) mode cell with Photo alignment technology have been widely used in many kinds of devices due to its excellent performance of LC display. In this paper, the local area cell parameter, include cell gap, pre‐tilt angle and twist angle of dosage have been compared. [ABSTRACT FROM AUTHOR]

The acoustic radiation force, originating from ultrasonic standing waves and utilized in numerous cell oriented acoustofluidic applications, is dependent on the acoustic contrast factor which describes the relationship between the acousto-mechanical properties of a particle and its surrounding medium. The acousto-mechanical properties of a cell population are known to be heterogeneously distributed but are often assumed to be constant over time. In this paper, we use microchannel acoustophoresis to show that the cell state within a cell population, in our case living and dead cells, influences the mechanical phenotype. By investigating the trapping location of viable and dead K562, MCF-7 and A498 cells as a function of the suspension medium density, we observed that beyond a specific medium density the viable cells were driven to the pressure anti-node while the dead cells were retained in the pressure node. Using this information, we were able to calculate the effective acoustic impedance of viable K562 and MCF-7 cells. The spatial separation between viable and dead cells along the channel width demonstrates a novel acoustophoresis approach for binary separation of viable and dead cells in a cell-size independent and robust manner. [ABSTRACT FROM AUTHOR]

Summary: Indoor and cell‐edge coverage has been a major issue of concern for predeployed traditional macrocell (MC)–based homogeneous cellular network. Moreover, with the extensive increase of mobile users and developments of smart and highly specified devices, user demands and activities have led to huge cellular traffic. The key solutions to these that include network upgradation, overlaying of small cells (SCs), and scaling of resources have turned out to be the major causes for intercell interference (ICI) and energy‐efficiency degradation in heterogeneous cellular networks (HetCNs). In this paper, authors have tried to analyze the downlink performance metrics of cell boundary users with MCs overlaying SCs for three‐cell circular and seven‐cell sectorized networks through frequency reuse (FR) schemes. This paper also discusses the impact of ICI being encountered by users and the effect of SCs on the energy efficiency of the network. The locations for SCs are perceived where user density is large and demands high data rate such as at hot‐spot (HS) areas, railway stations, shopping malls, working farms, and organization. The performance metrics sum rate, average user throughput, and energy efficiency are compared by employing FR‐1 (full spectrum) and FR‐3 (three subbands) among MCs and deployed SCs. For both scenarios, simulation results and analyses depict that without SCs, utilization of FR‐1 results in performance degradation due to ICI effects. However, the downlink performance of cell boundary user and energy efficiency of the network could be enhanced by overlaying SCs near cell boundaries of preexisting MCs along with the allocation of FR‐1. [ABSTRACT FROM AUTHOR]

This paper deals with the state of charge (SoC) estimation of a lithium-ion battery pack (LiBP) connected by some cells in series and parallel. The voltage noise, noise and current bias of current through the LiBP are taken into account in the SoC estimation problem. In order to describe the cell dynamic more accurately, especially for practical applications with charge and discharge amplitude varying suddenly, in this paper we use the second dynamic order model of the cell to estimate the SoC of the LiBP. By applying the sigma point Kalman filter (SPKF), the average SoC of the pack and bias current of current measurement are estimated by first estimator; the second estimator estimates the SoC differences of the cell modules from average SoC of the pack. The SoC of the cell modules are the sum of average SoCs of the pack and the SoC differences. By only using two estimators, the calculation complexity for SoC estimation is more reduced; this is very useful for the LiBP, which has the number of cells connected in a large series. This method was applied for the pack of SAMSUNG ICR18650-22P connected by seven cell modules; the cell modules were connected by nine cells in parallel; the LiBP was charged and discharged with amplitude varying suddenly. The estimated SoC of seven cell modules is smaller than 2% for a temperature operating range typically −5 °C to 45 °C. The comparison of the accuracy of SoC estimation based on the first and the second order dynamic models is made; the result shows that the SoC estimation used the second order dynamic model is more exact. [ABSTRACT FROM AUTHOR]

In this paper, we present a transparent mechanical stimulation device capable of uniaxial stimulation, which is compatible with standard bioanalytical methods used in cellular mechanobiology. We validate the functionality of the uniaxial stimulation system using human-induced pluripotent stem cells-derived cardiomyocytes (hiPSC-CMs). The pneumatically controlled device is fabricated from polydimethylsiloxane (PDMS) and provides uniaxial strain and superior optical performance compatible with standard inverted microscopy techniques used for bioanalytics (e.g., fluorescence microscopy and calcium imaging). Therefore, it allows for a continuous investigation of the cell state during stretching experiments. The paper introduces design and fabrication of the device, characterizes the mechanical performance of the device and demonstrates the compatibility with standard bioanalytical analysis tools. Imaging modalities, such as high-resolution live cell phase contrast imaging and video recordings, fluorescent imaging and calcium imaging are possible to perform in the device. Utilizing the different imaging modalities and proposed stretching device, we demonstrate the capability of the device for extensive further studies of hiPSC-CMs. We also demonstrate that sarcomere structures of hiPSC-CMs organize and orient perpendicular to uniaxial strain axis and thus express more maturated nature of cardiomyocytes. [ABSTRACT FROM AUTHOR]

In this paper, a high-voltage driver with a switch-capacitor cell and a current-sensing resistor for implementing the functions of zero-voltage switching (ZVS) and overcurrent protection is proposed. It has the following advantages: (1) By using a switch-capacitor cell for implementing the function of ZVS, we can reduce the switching losses of active switches. (2) By using a voltage-doubler circuit, we can easily obtain a high voltage (8 kV). (3) By incorporating a sensing resistor and a logic circuit, we can sense overcurrent conditions to achieve the function of protection. Therefore, the proposed high-voltage driver can increase efficiency and safety. To verify its performance, a prototype of the proposed high-voltage driver is built. The experimental results have confirmed that the proposed high-voltage driver with a switch-capacitor cell and a current-sensing resistor for implementing the functions of ZVS and overcurrent protection is suitable for application to air cleaners. [ABSTRACT FROM AUTHOR]

Fast speed of read operation and stability is the general need of memory device, SRAM read stability can be achieved by keeping high ION/IOFF ratio. In this paper we propose a 8T SRAM Cell that results in reduction of Read delay and increase the ION/IOFF ratio at the same time in comparison with conventional 6T SRAM Cell and 7T SRAM Cell at the cost of leakage power. This paper is aimed to increase ION/IOFF ratio while keeping the faster Read speed. [ABSTRACT FROM AUTHOR]

Due to the lack of uniform standards for pathological cell detection, it is difficult to identify. In order to improve the accuracy of pathological cell identification, this study combines the actual situation of cell detection based on traditional particle algorithm to construct a C-V model based on level set algorithm and curve evolution theory, which realizes the effective separation of different substances inside the cell. At the same time, in order to effectively extract the characteristics of cell images, this paper uses the global research method to extract the features of the research object and adopts the improved gray level co-occurrence matrix to extract the texture features, thus effectively improving the feature extraction quality. In addition, in order to study the accuracy of the algorithm model identification in this study, this paper designs a comparative experiment for performance analysis. The research shows that the proposed algorithm model has good performance, can achieve accurate recognition and feature extraction of pathological cells, has certain practical effects, and can provide theoretical reference for subsequent related research. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the lightning production of convective cells. The cells were detected by the MeteoSwiss Thunderstorms Radar Tracking (TRT) algorithm in the course of a lightning measurement campaign that took place in the summer of 2017 in the area surrounding the Säntis mountain, in the northeastern part of Switzerland. For this campaign, and for the first time in the Alps, a lightning mapping array (LMA) was deployed. In the first part of the paper, we examine the relationship between the intra-cloud (IC) and cloud-to-ground (CG) activity and the cell severity, as derived by the TRT algorithm, of a large dataset of cells gathered during the campaign. We also propose and analyse the performance of a new metric to quantify lightning intensity, the rimed-particle column (RPC) height and base altitude. In the second part, we focus on two of the most severe cells detected during the campaign that produced significantly different outcomes in terms of lightning activity. The paper shows that the newly proposed metric (RPC) seems to be a very promising predictor of lightning activity, particularly for IC flashes. Future lightning nowcasting algorithms should be probabilistic in nature and incorporate the polarimetric properties of the convective cells as well as the lightning climatology. [ABSTRACT FROM AUTHOR]

In this paper, we present a usability evaluation of a custom AR educational tool designed to improve students' understanding of the similarities and differences between plant and animal cells. We argue that the design of the Augmented Reality Plant & Animal Cells (ARPAC) tool promotes a self-driven approach to learning by presenting textbook content as interactive, 3D models that can be uncovered by exploring sections of their school textbooks with our app. Furthermore, the design of ARPAC can be mapped easily onto other subjects, providing teachers with additional pedagogical tools to utilize in the classroom. Preliminary results of a usability study support our initial design of a textbook-driven AR application to support learning in science subjects. [ABSTRACT FROM AUTHOR]

The authors have proposed a cell voltage equalizer with an LC series circuit in a previous work. The proposed circuit, however, has the disadvantage that the equalization time tends to be longer than that of other conventional equalizers. Therefore, the authors have studied some control methods to reduce the equalization time. This paper proposes a novel equalization time reduction method using the magnitude relation of each cell voltage estimated from the equalization current for the proposed equalizer. The proposed method can reduce the equalization time without an additional voltage sensor, so the size of the equalizer is not changed and the cost is not higher than an equalizer using the conventional control method. In addition, the characteristics and the effectiveness of the proposed method were verified by the simulations and the experiments. It was confirmed that the proposed method could reduce the equalization time to about 67.7% of that of the conventional control method by the experiments. [ABSTRACT FROM AUTHOR]

MCL, Mincle and Dectin‐2 are C‐type lectin receptors expressed by subsets of myeloid cells, and their genes cluster together in the APLEC/Dectin‐2 gene complex. We have previously shown that MCL and Mincle form a heterodimer in the rat, and others have shown that MCL and Dectin‐2 form a heterodimer in the mouse. In the rat, Dectin‐2 is a pseudogene, but here, we examine the association of the three receptors in human. In co‐transfection experiments analyzed with flow cytometry and immunoprecipitation, we here show that human MCL and Mincle form a disulphide‐linked heterodimer that associates with the signalling adaptor molecule FcεRIγ, in accordance with our previous findings in the rat. In contrast to previous findings in the rat, data in this paper indicate a direct association of MCL with FcεRIγ, as previously shown for mouse MCL. We were unable to demonstrate the formation of a heterodimer between human MCL and Dectin‐2. Thus, despite similarities, there may be important differences in the conformation of these receptors between rat, mouse and human, and this may have functional consequences. [ABSTRACT FROM AUTHOR]

In this work, a nanostructured conductive film possessing nanozyme features was straightforwardly produced via laser-assembling and integrated into complete nitrocellulose sensors; the cellulosic substrate allows to host live cells, while the nanostructured film nanozyme activity ensures the enzyme-free real-time detection of hydrogen peroxide (H 2 O 2) released by the sames. In detail, a highly exfoliated reduced graphene oxide 3D film decorated with naked platinum nanocubes was produced using a CO 2 -laser plotter via the simultaneous reduction and patterning of graphene oxide and platinum cations; the nanostructured film was integrated into a nitrocellulose substrate and the complete sensor was manufactured using an affordable semi-automatic printing approach. The linear range for the direct H 2 O 2 determination was 0.5–80 μM (R2 = 0.9943), with a limit of detection of 0.2 μM. Live cell measurements were achieved by placing the sensor in the culture medium, ensuring their adhesion on the sensors' surface; two cell lines were used as non-tumorigenic (Vero cells) and tumorigenic (SKBR3 cells) models, respectively. Real-time detection of H 2 O 2 released by cells upon stimulation with phorbol ester was carried out; the nitrocellulose sensor returned on-site and real-time quantitative information on the H 2 O 2 released proving useful sensitivity and selectivity, allowing to distinguish tumorigenic cells. The proposed strategy allows low-cost in-series semi-automatic production of paper-based point-of-care devices using simple benchtop instrumentation, paving the way for the easy and affordable monitoring of the cytopathology state of cancer cells. [ABSTRACT FROM AUTHOR]

A conclusion has not yet been reached on how exactly the human visual system detects curvature. This paper demonstrates how orientation-selective simple cells can be used to construct curvature-detecting neural units. Through fixed arrangements, multiple plurality cells were constructed to simulate curvature cells with a proportional output to their curvature. In addition, this paper offers a solution to the problem of narrow detection range under fixed resolution by selecting an output value under multiple resolution. Curvature cells can be treated as concrete models of an end-stopped mechanism, and they can be used to further understand "curvature-selective" characteristics and to explain basic psychophysical findings and perceptual phenomena in current studies. [ABSTRACT FROM AUTHOR]

In this paper we use Boolean framework to redefine coupled cell networkss, originally described in [2]. We also analyze some of the important properties of Boolean coupled cell networkss. In the second part of this paper we focus on properties of a quotient networks. We redefine the concept of a quotient to suit Boolean network framework. Next, we investigate in details the networks in which two-cell bidirectional ring and three-cell bidirectional ring arise as quotients. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Nanomaterials are proven to affect the biological activity of mammalian and microbial cells profoundly. Despite this fact, only surface chemistry, charge, and area are often linked to these phenomena. Moreover, most attention in this field is directed exclusively at nanomaterial cytotoxicity. At the same time, there is a large body of studies showing the influence of nanomaterials on cellular metabolism, proliferation, differentiation, reprogramming, gene transfer, and many other processes. Furthermore, it has been revealed that in all these cases, the shape of the nanomaterial plays a crucial role. In this paper, the mechanisms of nanomaterials shape control, approaches toward its synthesis, and the influence of nanomaterial shape on various biological activities of mammalian and microbial cells, such as proliferation, differentiation, and metabolism, as well as the prospects of this emerging field, are reviewed.

In this paper, we build phase-field models for the actomyosin driven cell oscillations. In our modeling, an oscillation starts from an actin cortex breakage. After the breakage, due to the unbalanced distribution of actin and myosin, there is unbalanced contraction force in different membrane components, which then results in the lipids transferring to the bulged membrane compartment. As such we can observe a cell oscillation. During the whole process, the actin and myosin polymerization and depolymerization play important roles. We give detailed formulations under the framework of phase-field methodology, in which phase-field functions are used to describe different parts of the cell membrane, integrated with the distribution of the actin and myosin at different components. The whole system is described as a set of time-dependent partial differential equations in three-dimensional space. Forward Euler method is used to solve the system. The spectral method is used for spatial discretizations for efficiency and accuracy purpose. Given carefully selected parameters, three-dimensional simulations are performed and compared with biological images. The simulations prove that actomyosin dynamics are the major reasons for cell oscillations. Further, our method can be easily extended into the simulations of cell polarization. We also compared our numerical simulations with biological experiments. This modeling gives an example of applying diffusive interface methods toward complex biology experiments.

The error‐correcting performance of multi‐level‐cell (MLC) NAND flash memory is closely related to the block length of error‐correcting codes (ECCs) and log‐likelihood‐ratios of the read‐voltage thresholds. Driven by this issue, this paper optimizes the read‐voltage thresholds for MLC flash memory to improve the decoding performance of ECCs with finite block length. First, through the analysis of channel coding rate and decoding error probability under finite block length, the optimization problem of read‐voltage thresholds to minimize the maximum decoding error probability is formulated. Second, a cross‐iterative search algorithm to optimize read‐voltage thresholds under the perfect knowledge of flash memory channel is developed. However, it is challenging to analytically characterize the voltage distribution under the effect of data retention noise. To address this problem, a deep neural network (DNN)‐aided optimization strategy to optimize the read‐voltage thresholds is developed, where a multi‐layer perception network is employed to learn the relationship between voltage distribution and read‐voltage thresholds. Simulation results show that, compared with the existing schemes, the proposed DNN‐aided read‐voltage threshold optimization strategy with a well‐designed Low Density Parity Check (LDPC) code can not only improve the program‐and‐erase endurance but also reduce the read latency. [ABSTRACT FROM AUTHOR]

Following publication of the original article [1], we have been notified that the tagging of one of the author names was done incorrectly in the XML version of the paper. The online and pdf versions of this paper are not affected by the change. Original and corrected tagging can be seen below. The original article has been corrected. [ABSTRACT FROM AUTHOR]

This paper proposes a complete and full automation framework of evaluating design rules (DRs) to facilitate the process of design technology co-optimization (DTCO), which is highly demanded in 14-nm and beyond technologies. Our proposed framework explores the changes of DRs and evaluates the impacts on the number and types of DR violations as well as the resulting cell/chip layout area. Precisely, the core engine of our DR evaluation framework for DTCO, the automatic cell layout generator, consists of key enabling techniques for standard cell layout optimization. They are integrated coherently to seamlessly support the advanced process technologies using FinFET transistors, complex DRs, and double patterning (DP) lithography. Also, the tight integration of our automatic cell layout generation into the DR evaluation framework with diverse analysis features enables the DTCO process to be much faster and more efficient. We provide a set of experimental data not only to show how much our proposed enabling techniques are effective in optimizing layouts but also to show how effectively our framework explores and analyzes the DTCO parameters (e.g., ground DRs and DP DRs). [ABSTRACT FROM AUTHOR]

This paper presents a trajectory planning strategy for collision avoidance in unmanned aerial vehicles. First, a varying cell strategy is proposed to integrate aerodynamic constraints into trajectory planning. Basic avoidance actions in the varying cell strategy are adapted accordingly to go through different cells, enabling more flexible avoidance maneuvers. Second, given the limited decision-making time involved, offline and online path planning methods are developed to increase the convergence rate. Finally, Monte Carlo simulations demonstrate that the proposed method satisfies aerodynamic constraints, while both the convergence and collision avoidance rates are better than that achieved by fixed cell-based methods. [ABSTRACT FROM AUTHOR]

Peroxynitrite (ONOO−) has been proven to participate in various physiological and pathological processes, and may also be a contributing factor in many diseases. In view of this, there is a need to develop detection tools for unambiguously tracking a small amount of endogenous ONOO− to reveal its exact mechanisms. In this paper, a colorimetric and red-emitting fluorescent probe Red-PN, based on a rhodamine-type fluorophore and hydrazide reactive site is described. The probe Red-PN possesses the advantages of rapid response (within 5 s), visual color change (from colorless to pink), preeminent sensitivity (detection limit = 4.3 nM) and selectivity. Because of these outstanding performances, it was possible to accurately detect endogenous ONOO−. It was encouraging that the probe Red-PN could be used effectively for tracking the relatively low levels of endogenous and exogenous ONOO− in living cells and zebrafish. Thus, it is envisioned that the probe Red-PN would have promising prospects in applications for imaging ONOO− in a variety of biological settings. [ABSTRACT FROM AUTHOR]

Cascaded H-bridge (CHB) inverter is the most widely used topology for a medium-voltage drive system due to the high degree of modularity, easier implementation of medium output voltage, and the ability to continuous operation under the cell fault condition. Because each power cell of CHB should have isolated dc source, multiwinding input transformer and three-phase active front end (AFE) are generally used for regenerative applications. The whole system can be simplified by replacing the three-phase AFE with single-phase AFE. However, if the control strategy of normal operation is adopted under the cell fault condition, input power imbalance among three phases inevitably occurs. In that situation, not only faulty cells, but also some unscathed cells should be excluded with giving up the maximum capability of the system, not to deteriorate grid current. This paper proposes a control scheme against the cell fault condition of the single-phase AFE CHB. By applying the proposed control scheme to the system, dc-link voltage of each cell and grid current are well regulated without imbalance even under the cell fault conditions. Finally, it can minimize the number of undamaged cells which should be turned off and maximize the capability of the system under the cell fault condition. Simulation and experimental results are provided to verify the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

In the near future, electrification will be introduced to heavy-duty vehicles and passenger cars. However, the wireless power transfer (WPT) requires high energy levels, and the suitability of various types of WPT systems must be assessed. This paper describes a method for solving technical and safety issues associated with this technology. We exposed human corneal epithelial (HCE-T) cells derived from the human eye to 5.8-GHz electromagnetic fields for 24 h. We observed no statistically significant increase in micronucleus (MN) frequency in cells exposed to a 5.8-GHz field at 1 mW/cm2 (the general public level in ICNIRP) relative to sham-exposed or incubator controls. Similarly, the DNA strand breaks, and the expression of heat shock protein (Hsp) Hsp27, Hsp70, and Hsp $90\alpha $ exhibited no statistically significant effects as a result of exposure. These results indicate that the exposure to 5.8-GHz electromagnetic fields at 1 mW/cm2 for 24 h has little or no effect on micronucleus formation, DNA strand breaks, and Hsp expression in human eye cells. [ABSTRACT FROM AUTHOR]

The aim of this paper is to introduce a new kind of reflectarray cell with both amplitude and phase control abilities. A slot is added in the ground of an arbitrary conventional cell for this purpose. A slotted cell having a square patch is investigated to verify the effectiveness of the proposed approach. This cell is used to reduce the side lobe level of a reflectarray antenna. [ABSTRACT FROM AUTHOR]

The rapidly changing influenza virus has remained a consistent threat to the well-being of a variety of species on the planet. Influenza virus' high mutation rate has allowed the virus to rapidly and continuously evolve, as well as generate new strains that are resistant to the current commercially available antivirals. Thus, the increased resistance has compelled the scientific community to explore alternative compounds that have antiviral effects against influenza virus. In this paper, the authors systematically review numerous herbal extracts that were shown to have antiviral effects against the virus. Specifically, the herbal antiviral targets mainly include hemagglutinin, neuraminidase and matrix 2 proteins. In some instances, herbal extracts inhibited the replication of oseltamivir-resistant strains and certain pentacyclic triterpenes exhibited higher antiviral activity than oseltamivir. This paper also explores the possibility of targeting various host-cell signaling pathways that are utilized by the virus during its replication process. Infected cell pathways are hijacked by intracellular signaling cascades such as NF-kB signaling, PI3K/Akt pathway, MAPK pathway and PKC/PKR signaling cascades. Herbal antivirals have been shown to target these pathways by suppressing nuclear export of influenza vRNP and thus inhibiting the phosphorylation signaling cascade. In conclusion, copious amounts of herbal antivirals have been shown to inhibit influenza virus, however further studies are needed for these new compounds to be up to modern pharmacological standards. [ABSTRACT FROM AUTHOR]

Extracellular measurement of uptake/release kinetics and associated concentration dependencies provides mechanistic insight into the underlying biochemical processes. Due to the recognized importance of preserving the natural diffusion processes within the local microenvironment, measurement approaches which provide uptake rate and local surface concentration of adherent cells in static media are needed. This paper reports a microelectrode array device and a methodology to measure uptake kinetics as a function of cell surface concentration in adherent 2D cell cultures in static fluids. The microelectrode array simultaneously measures local concentrations at five positions near the cell surface in order to map the time-dependent concentration profile which in turn enables determination of surface concentrations and uptake rates, via extrapolation to the cell plane. Hydrogen peroxide uptake by human astrocytes (normal) and glioblastoma multiforme (GBM43, cancer) was quantified for initial concentrations of 20 to 500 μM over time intervals of 4000 s. For both cell types, the overall uptake rate versus surface concentration relationships exhibited non-linear kinetics, well-described by a combination of linear and Michaelis–Menten mechanisms and in agreement with the literature. The GBM43 cells showed a higher uptake rate over the full range of concentrations, primarily due to a larger linear component. Diffusion-reaction models using the non-linear parameters and standard first-order relationships are compared. In comparison to results from typical volumetric measurements, the ability to extract both uptake rate and surface concentration in static media provides kinetic parameters that are better suited for developing reaction-diffusion models to adequately describe behavior in more complex culture/tissue geometries. The results also highlight the need for characterization of the uptake rate over a wider range of cell surface concentrations in order to evaluate the potential therapeutic role of hydrogen peroxide in cancerous cells. [ABSTRACT FROM AUTHOR]