Total Current Research Articles

Integrated Electro-Thermal Model for Li-Ion Battery Packs

Lithium-ion battery is considered one of the most attractive energy storage systems for electric vehicles. However, one of its main drawbacks is the sensitivity to temperature. In a battery pack composed of lithium-ion batteries, during the charge/discharge operations, the temperature gradually increases, especially in the batteries positioned in the central part of the battery pack. This leads the central batteries to age faster and exposes them to the risk of a thermal runaway. In order to mitigate these problems, thermal management systems are needed. However, for the implementation of the control, it is important to know the temperature distribution inside the whole pack. In this paper, an integrated electro-thermal model capable of estimating the thermal behavior of each battery cell, composing the battery pack, only knowing the total current and ambient temperature, is proposed and analyzed. The proposed model was tuned and validated by means of experimental results. The circuital approach used in this model gives good results with a low degree of complexity.

Formation and termination of runaway beams during vertical displacement events in tokamak disruptions

A simple 0D model which mimics the plasma surrounded by the conducting structures (Kiramov and Breizman 2017 Phys. Plasmas 24 100702) and including self-consistently the vertical plasma motion and the generation of runaway electrons during the disruption is used for an assessment of the effect of vertical displacement events on the runaway current formation and termination. The total plasma current and runaway current at the time the plasma hits the wall is estimated and the effect of injecting impurities into the plasma is evaluated. In the case of ITER, with a highly conducting wall, although the total plasma current when the plasma touches the wall is the same for any number of injected impurities, however the fraction of the plasma current carried by runaway electrons can significantly decrease for large enough amounts of impurities. The plasma velocity is larger and the time when the plasma hits the wall shorter for lower runaway currents, which are obtained when larger amounts of impurities are injected. When the plasma reaches the wall, the scraping-off of the runaway beam occurs and the current is terminated. During this phase, the plasma vertical displacement velocity and electric field can substantially increase leading to the deposition of a noticeable amount of energy on the runaway electrons (∼hundreds of MJ). It is found that an early second impurity injection reduces somewhat the amount of energy deposited by the runaways. Also larger temperatures of the companion plasma during the scraping-off might be efficient in reducing the power fluxes due to the runaways onto the PFCs. The plasma reaches the q a = 2 limit before the runaway electron current is terminated and by that time the amount of energy deposited on the runaway electrons can be substantially lower than that expected until the beam is fully terminated. Negligible additional conversion of magnetic into runaway kinetic energy is predicted during the runaway deconfinement following the large magnetic fluctuations after q a = 2 is crossed for characteristic deconfinement times lower than 0.1 ms which is a characteristic timescale for ideal MHD instabilities to develop.

Negative ion density in the ion source SPIDER in Cs free conditions

The SPIDER experiment, operated at the Neutral Beam Test Facility of Consorzio RFX, Padua, hosts the prototype of the H−/D− ion source for the ITER neutral beam injectors. The maximization of the ion current extracted from the source and the minimization of the amount of co-extracted electrons are among the most relevant targets to accomplish. The Cavity Ring-Down Spectroscopy diagnostic measures the negative ion density in the source close to the plasma grid (the plasma-facing grid of the ion acceleration system), so to identify the source operational parameters that maximize the amount of negative ions which can be extracted. In this study SPIDER was operated in hydrogen and deuterium in Cs-free conditions, therefore negative ions were mostly produced by reactions in the plasma volume. This work shows how the magnetic filter field and the bias currents, present in SPIDER to limit the amount of co-extracted electrons, affect the density of negative ions available for extraction. The results indicate that the magnetic filter field in front of the acceleration system should be set between about 1.6 mT, condition that maximizes the density of available negative ions, and about 3.2 mT, condition that minimizes the ratio of electron current to ion current. The negative ion density also resulted to be maximized when the plasma grid and its surrounding bias plate was positively biased against the source body with a total current in the range 0–100 A. The paper shows also how much, in Cs-free conditions, the electric fields in the acceleration system can affect the density of negative ions in the source, close to the plasma grid apertures.

Evaluating Compulsive‐Like Drug‐Taking Using Signaled and Unsignaled Footshock Procedures in Male and Female Rats Self‐Administering MDPV

A subset of rats that self‐administer synthetic cathinones, such as 3,4‐methylenedioxypyrovalerone (MDPV), develop high levels of drug intake and patterns of responding similar to the compulsive, binge‐like patterns of cathinone (e.g., “bath salts”) use reported in humans. Though high‐responder rats exhibit some behaviors thought to be related to substance use disorder, the effects of punished responding in these rats were unknown. These studies evaluated whether (1) high‐responder rats were less sensitive to footshock‐punished responding than low‐responder rats using both unsignaled and signaled footshock procedures; (2) whether sensitivity to footshock was dependent on the self‐administered dose of MDPV. Inhibition curves for unsignaled footshock (0.05‐0.9 mA, increasing across sessions) were evaluated in forty adult Sprague Dawley rats self‐administering 0.01, 0.032, and 0.1 mg/kg/infusion MDPV under a FR5 schedule of reinforcement; footshocks were paired with ~50% of drug infusions. Rats were then trained on a signaled footshock procedure, in which a change in stimulus conditions signaled that the next infusion would be paired with a footshock (intensities individualized to each rat’s IC50). Rats could avoid this footshock by withholding responding for 30‐sec. After rats learned the signaled shock procedure, inhibition curves were generated using a range of footshock intensities (0.05‐0.9 mA). High‐ and low‐responder rats were similarly sensitive to unsignaled punishment by footshock (mean IC50s‐ high‐responders: 0.30mA; low‐responders: 0.36mA). However, high‐responder rats (mean: 45mA) received significantly more total current than low‐responder rats (mean: 18mA). Compared to low‐responder rats, high‐responder rats respond more in the presence of the signal indicating impending shock and avoid a smaller proportion of shocks. This suggests high‐responder rats may be less able to adapt their behavior in response to a stimulus associated with punishment. These studies suggest that the high levels of drug‐taking observed in the high‐responder rats reflects a compulsive‐like pattern of responding, which may be related to continued use despite adverse consequence, a DSM symptom of substance use disorder.

Select Amino Acid Formulation Influenced Anion Secretion Induced by Th2 Cytokines in Human Bronchial Epithelial Cells (HBECs)

IntroductionAirway surface liquid is tightly regulated by ion channels and/or transporters, and plays a critical role in inflammatory airway diseases, such as ARDS, and in edema fluid clearance during lung injury. Although beta‐adrenergic agonists have been shown to improve alveolar fluid clearance, they have limited effect in late stages of ARDS due to reduced epithelial beta‐adrenergic receptor function or agonist delivery to target regions. CFTR, CLCA2, TMEM16A, and alternative Cl‐/HCO3‐ exchangers (e.g., SLC4 family) are known to be expressed in lung epithelia. Their relative contribution during late stages of lung injury where TH2 cytokines such as IL13 are elevated is not fully understood. The expression pattern of these anion channels are dysregulated in ARDS, and restoration of channel activities could improve fluid accumulation within the lung. In the present study, various anion channel and/or exchanger activities were measured in HBECs exposed to IL13. We have shown that select amino acids influence anion channel activity. Therefore, the effect of a proprietary amino acid formulation on specific anion channels were studied in IL13‐treated HBECs.MethodsTransepithelial short‐circuit current (Isc) was sequentially blocked using inhibitors for ENaC (benzamil), CFTR CFTRInh172), TMEM16A (CaCCInhA01) and Na+/K+/2Cl‐ co‐transporter (bumetanide) in differentiated HBECs mounted in Ussing chambers. Patch‐clamp whole‐cell recordings were performed to determine anion channel activity after IL13 treatment, and channel and/or exchanger expression was analyzed by immunofluorescence.ResultsIL13 increased benzamil‐insensitive (anion) Isc (87.5 ± 4.7 µA.cm‐2 vs 21.9 ± 1.8 µA.cm‐2; P <0.001) and decreased CFTR Isc (1.4 ± 0.52 µA.cm‐2 vs 12.2 ± 0.83 µA.cm‐2; P <0.001) compared to controls. Amino acids reduced benzamil‐insensitive Isc (55.9 ± 4.8 µA.cm‐2; P <0.001) and increased CFTR Isc (6.7 ± 0.75 µA.cm‐2; P <0.001). There was no change in TMEM16A Isc with IL13 treatment. Bumetanide‐sensitive Isc was higher in IL13‐treated cells compared to controls (52.5 ± 3.6 µA.cm‐2 vs 5.5 ± 0.62 µA.cm‐2; P <0.001) suggesting anion secretion via alternate mechanisms, and amino acids decreased bumetanide‐sensitive anion secretion (20.5 ± 2.9 µA.cm‐2; P <0.001). Similarly, whole‐cell patch clamp recordings showed that amino acids restored the CFTR response in IL13‐treated cells. Immunofluorescence imaging demonstrated decreased CFTR expression with IL13, while amino acids recovered CFTR at the apical membrane.ConclusionTreatment with IL13 increased anion secretion while reducing CFTR channel activity in HBECs. Amino acid formulation restored CFTR activity and decreased total anion current in the presence of IL13. These studies suggest anion secretion via alternate anion secretory pathways. Future studies should be directed at understanding the link between CFTR and alternate anion channels in conditions associated with elevated IL13, and how amino acids regulate these channel and/or exchanger functions

Temperature and pH tolerance ratiometric aptasensor: Efficiently self-calibrating electrochemical detection of aflatoxin B1.

Ratiometric electrochemical aptasensors based on the two different redox reporters can hardly achieve the efficient self-calibration, as a result of variations between reporters. In this work, we reported a ratiometric electrochemical aptasensor using ferrocene as a single redox reporter (Fc) to achieve self-calibrating electrochemical detection of aflatoxin B1 (AFB1). The hybrid duplex of Fc-labeled AFB1 aptamer (Fc-Apt) and Fc-labeled assistant DNA (Fc-aDNA) was designed to construct the sensing interface. Such DNA structure adopted the fixed molar ratio (1:1) and locations (the distances to electrode) of these two types of Fc (i.e., Fc-Apt and Fc-aDNA). In this way, the ratio of redox currents from Fc-Apt (IFc-Apt) and Fc-aDNA (IFc-aDNA) kept stable under the varied temperatures (15-40°C) and pH values (4-10). Moreover, values of IFc-Apt and IFc-aDNA under the different conditions can be calculated simply by recording the total current of Fc (IFc-total). For analysis, the recognition of AFB1 by Fc-Apt led to the striping of their complex from the aptasensor, resulting in a decrease in IFc-Apt while IFc-aDNA remained stable. Consequently, the developed aptasensor using the ratio of IFc-Apt/IFc-aDNA as a yardstick offered a linear range of 0.1-10000pgmL-1 with a detection limit of 0.012pgmL-1 for the detection of AFB1. The applicability of aptasensor was validated by corn sample analysis, which exhibited comparable reliability and accuracy of gold standard method, i.e., HPLC-MS/MS. Our work provided an efficient strategy to fabricate high-performance ratiometric electrochemical aptasensors.

Rapid Characterization of Bacterial Lipids with Ambient Ionization Mass Spectrometry for Species Differentiation.

Ambient ionization mass spectrometry (AIMS) is both labor and time saving and has been proven to be useful for the rapid delineation of trace organic and biological compounds with minimal sample pretreatment. Herein, an analytical platform of probe sampling combined with a thermal desorption–electrospray ionization/mass spectrometry (TD-ESI/MS) and multivariate statistical analysis was developed to rapidly differentiate bacterial species based on the differences in their lipid profiles. For comparison, protein fingerprinting was also performed with matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) to distinguish these bacterial species. Ten bacterial species, including five Gram-negative and five Gram-positive bacteria, were cultured, and the lipids in the colonies were characterized with TD-ESI/MS. As sample pretreatment was unnecessary, the analysis of the lipids in a bacterial colony growing on a Petri dish was completed within 1 min. The TD-ESI/MS results were further performed by principal component analysis (PCA) and hierarchical cluster analysis (HCA) to assist the classification of the bacteria, and a low relative standard deviation (5.2%) of the total ion current was obtained from repeated analyses of the lipids in a single bacterial colony. The PCA and HCA results indicated that different bacterial species were successfully distinguished by the differences in their lipid profiles as validated by the differences in their protein profiles recorded from the MALDI-TOF analysis. In addition, real-time monitoring of the changes in the specific lipids of a colony with growth time was also achieved with probe sampling and TD-ESI/MS. The developed analytical platform is promising as a useful diagnostic tool by which to rapidly distinguish bacterial species in clinical practice.

Intense Laser Pulse Interaction With Graphene and Graphene Ribbons.

In this work we investigate quantum mechanically the interaction of an intense ultrashort laser pulse with the graphene monolayer as well as with the armchair graphene ribbons of different widths. We consider a tight binding (TB) Hamiltonian of the monolayer graphene and give two rules for deriving the dispersion relations of the armchair graphene ribbons of any width, N, from the TB eigenvalues of the monolayer. The band structure of the monolayer and the armchair ribbons of different widths are discussed with illustrations. The time-dependent wavefunctions of the systems and the expectation values of interest are determined by solving the coupled equations of the band amplitudes “exactly” (numerically). First, simulations are made for the population excitation in the conduction band (CB) from the valence band (BV), the VB-CB interband correlation (or “coherence”), the intraband, the interband and the total currents in the monolayer graphene. The graphene currents are compared with the corresponding currents induced in an armchair ribbon (width, N = 3). The change from the 2D monolayer to the 1D ribbon shows a remarkable transition of the dominance of the intraband current that leads to a near steady total current in the monolayer, to a dominance of the interband current in the ribbon that induces an oscillatory current in the ribbon beyond the pulse duration. The difference observed might be a combined effect of the “confinement” in one dimention and a finite band-gap minimum in the case of the ribbon. However, this transition should be further investigated for better clarity. A brief comparison of the radiation spectra emitted from the monolayer and from the ribbon is also made. They show a grossly similar structure and a relative insensitivity with respect to the detailed structure of the targets chosen. This might be due to the dominance of virtual continuum-continuum transitions, to and from the bands states, that lie behind the fundamental quantum process of high harmonic emissions. Lastly, the dependence of the charge currents, induced in a ribbon of unit width (N = 1), on the carrier-envelope-phase (CEP) of the incident laser pulse is investigated. It is seen that the shape of the main part of the current produced in the ribbon can be fully reversed by changing the CEP of the ultrashort laser pulse from 0 to π. More generally, it is suggested that the pulse shape of the charge carriers in the ribbon could be designed by similarly tailoring the form of the vector potential of the incident laser pulse.

Equal Current Sharing Parallelly Connected Interleaved Boost Converter in DC Microgrid using Control Algorithm

In this paper, a micro grid based current sharing between parallelly connected second order Boost Converter and Interleaved Boost Converter is proposed. As the output of PV is not predictable, an MPPT based on the Adaptive Neuro Fuzzy Inference System (ANFIS) is used to manage the second order Boost Converter. To offer exact sharing of current between parallel modules in converters, a droop control mechanism is utilized. The PV system’s maximum power is tracked using a PI controller, so as to maintain constant DC link voltage at different temperature conditions. Using a PI assisted Bidirectional battery converter, the voltage of the battery is maintained. The nominal voltage for each converter is modified by comparing each converter’s output current to the total load current. The entire system is validated through a MATLAB simulation.

DC response, low-frequency noise, and TID-induced mechanisms in 16-nm FinFETs for high-energy physics experiments

Total-ionizing-dose (TID) mechanisms are evaluated in 16 nm Si bulk FinFETs at doses up to 1 Grad(SiO2) for applications in high-energy physics experiments. The TID effects are evaluated through DC and low-frequency noise measurements by varying irradiation bias conditions, transistor channel lengths, and fin/finger layouts. The TID response of nFinFETs irradiated under positive gate bias at ultrahigh doses shows a rebound of threshold voltage with significant increase in the 1/f noise amplitude. The degradation is related to the generation of border and interface traps at the upper corners of STI oxides and at the gate oxide/channel interfaces. In contrast, pFinFETs have the worst degradation due to positive charge trapping in STI oxides, which severely degrades the device transconductance and total drain current, while negligible effects are visible in the threshold voltage and 1/f noise. The TID sensitivity depends strongly on the transistor layout. Short-channel devices have the best TID tolerance thanks to the influence of halo implantations, while pFinFETs designed with low number of fins have the worst degradation because of high densities of positive charge in the surrounding thick STI oxides. As a guideline for IC design, short-channel transistors with more than 4-fins may be preferred in order to facilitate circuit qualification.

Power recovery of the PV arrays under partial shading by a power electronic compensator

The partial shading phenomenon in some modules of the PV arrays limits the total current of the series modules and reduces the total output power. In this paper, a power electronic compensator with a multi-winding transformer is presented to recover the undelivered energy of the shaded modules. The proposed configuration compensates reduced currents due to the partial shading on the series modules by injecting the required currents into parallel circuits of the shaded modules. The unshaded modules provide the compensatory currents by creating a common flux into the core of the multi-winding transformer. The average current and the output power of the PV array are considerably improved under partial shading conditions. The proposed configuration has a very simple and sensorless control structure, and its power electronic elements are less than other improving configurations. The simulation and experimental results confirm the presented analytical relations and desirable performance of the proposed configuration to recover the undelivered energy of the PV array under the partial shading conditions.

Comparative study on dark current mechanisms of n-on-p and p-on-n long-wavelength HgCdTe infrared detectors

The dark current density versus voltage (J-V) curves of long-wavelength mercury cadmium telluride (HgCdTe, MCT) infrared detectors with planar n-on-p and p-on-n structures are measured and compared in this study. The dark currents are decomposed into diffusion, generation–recombination (GR), trap-assisted tunneling (TAT), band-to-band tunneling (BBT) and shunt current for the two types of devices. It was found that the dark current is dominated by diffusion current at -0.05 V in the temperature range of 55–130 K for both of the two devices. Due to the longer minority carrier lifetime, the diffusion current of p-on-n device is suppressed and the total dark current is around one order of magnitude lower than that of n-on-p device at small reverse bias voltage. The tunneling current becomes the main ingredient of dark current at -0.3 V when the operating temperature is lower than 65 K. Because of the higher trap density in the depletion region, the TAT current is more obvious for n-on-p device. The larger donor and acceptor concentrations lead to a larger BBT current of p-on-n device.

On the chemistry, photocatalytical, and corrosion behavior of co-sputtered tantalum and titanium oxynitride thin films

Direct current magnetron co-sputtered titanium and tantalum based oxynitride coatings (TaTiON) were analyzed in terms of their chemistry, surface morphology, surface energy, photocatalytic activity, and corrosion resistance. The variable parameter for the deposition was the applied current on each target, changing between 0.75A and 0.25A for the Ta target, and from 0.25A to 0.75 A for the Ti target, to obtain a total current of 1A. Reference single-sputtered samples (TaON and TiON) were deposited under identical conditions. It was observed that a higher degree of oxidation occurred in the samples deposited with higher current on the Ti target, while nitriding and oxynitriding processes occurred only on the surfaces of the films containing Ta. In terms of surface roughness, the co-sputtered coatings exhibited significantly smaller values, compared to the single-sputtered coatings. The highest photodegradation efficiency was registered for the co-sputtered sample which contains the highest N concentration. The corrosion rate, obtained from electrochemical tests, varies in a rather large domain, as function of the chemical species in the coatings.

Many Body Current Density from Foldy–Wouthuysen Transformation of the Dirac–Coulomb Hamiltonian

This paper analyzes how special relativity changes the equation for the many-body-induced current density starting from the Foldy–Wouthuysen diagonalization of the Dirac–Coulomb Hamiltonian. This current density differs from that obtained with the Gordon decomposition due to the presence of a spin-orbit coupling contribution not considered before for many-body molecular systems. This contribution diverges on atomic nuclei due to the nature of the point charges considered in the nonrelativistic approach, demonstrating that conventionally used nonrelativistic methods are not suitable for dealing with spin effects such as spin-orbit coupling or effects smaller than α2, with α the fine structure constant, and that a fully relativistic approach with a finite charge should be used. Despite the singularity, the spin-orbit coupling current becomes an important contribution to the total current in open-shell systems with high-spin multiplicity and a high atomic number in the nuclear proximity. On long ranges, this contribution is overcome by the Coulomb potential and the derived electric field which decays very quickly for small distances from nuclear charges. An evaluation of this spin-orbit current has been performed in the linear response approach at the HF/DFT level of theory.

Modelling of Solar PV under Varying Condition with an Improved Incremental Conductance and Integral Regulator

The introduction of solar photovoltaic (PV) systems would provide electricity accessibility to rural areas that are far from or have no access to the grid system. Various countries are planning to reduce their emissions from fossil fuel, due to its negative effects, by substituting with renewable energy resources. The use of solar PV systems is expanding globally because of growing energy demands and depleting fossil fuel reserves. Grid integration of the solar system is expected to increase further in the near future. However, the power output of solar PV systems is inherently intermittent, and depends on the irradiance and the temperature operation of the solar cell, resulting in a wide range of defects. Hence, it is vital to extract peak power from the solar panel in all conditions to provide constant power to the load. This paper presents a tracking control method of the peak output power of a solar PV system connected to a DC-DC boost converter using an improved incremental conductance and integral regulator (IC + IR). The research was carried out because the solar PV output is dependent on environmental parameters, such as solar insolation and temperature. Therefore, it is pertinent to forecast the peak power point in outdoor conditions and to operate at that point, so that solar PV can produce the highest output each time it is used. A peak power point strategy that maximizes the output of a solar PV array is proposed. This method establishes the maximum output operation point under the effects of the solar insolation and the module temperature. An automatic converter restoration scheme with block/de-block signal control is proposed to protect the converters from the higher phase current, total capacitor voltage deviation, grid disturbance, and fault current. The proposed scheme also tracks the peak power point (PPP) of the solar array with stable output voltage under varying operating conditions. It reduces the error signal and ripples at the PPP during instantaneous and incremental conductance to zero. In addition, it controls the solar PV system under constantly changing climatic conditions, and thus improves the system efficiency.

Quantitative criteria of considering AC infeed in DC fault assessment of modular multilevel converters

An accurate and efficient DC fault current assessment of modular multilevel converters (MMCs) is critical for designs and protection. The state-of-the-art often ignores the impact of the AC infeed in the DC fault assessment without MMC blocking. However, whether the AC infeed needs to be considered or not is a controversial problem. This paper proposes quantitative criteria to determine the necessity of considering the AC infeed in the fault current assessment. The method is based on the premise that the MMC blocking has not occurred. Based on the average model of the MMC, the fault current contribution from the AC side is quantified under different control schemes. The criteria are established by a contributing ratio of the AC infeed over the total fault current. The obtained criteria only rely on the system and control parameters, which enable designers to identify the impact of ignoring the AC infeed in the DC fault assessment. The effectiveness of the proposed criteria is validated by two case studies and two different control schemes. The results reveal that the submodule (SM) capacitance and the number of SMs have a large impact on the AC infeed contribution.

Insights into Electronucleation and Electrodeposition of Nickel from a Non-aqueous Solvent Based on NiCl2·6H2O Dissolved in Ethylene Glycol

This work deals with nickel electronucleation and growth processes onto a glassy carbon electrode from NiCl2·6H2O dissolved in ethylene glycol (EG) solutions with and without 250 mM NaCl as a supporting electrolyte. The physicochemical properties of EG solutions, namely, viscosity and conductivity, were determined for different Ni(II) concentrations. From cyclic voltammetry, it was found that in the absence of the supporting electrolyte, the cathodic efficiency of Ni electrodeposition is about 88%; however, in the presence of the supporting electrolyte, the cathodic efficiency was reduced to 26% due to water (added along the supporting electrolyte) reduction on the growing surfaces of Ni nuclei. This side reaction produced both H2(g) and OH- ions. Part of the former was occluded in Ni, and the latter reacted with Ni(II) ions in EG forming passivation products such as Ni(OH)2(s). Moreover, it was shown that metallic Ni did not catalyze the EG reduction in this system. From chronoamperometry, it was shown that in the absence of the supporting electrolyte, the amount of Ni electrodeposits, for the same overpotential and time, was higher than in the presence of the supporting electrolyte. The j-t plots recorded in the latter system, for different Ni(II) concentrations, were analyzed using a model which involves a contribution due to multiple 3D nucleation and diffusion-controlled growth and another related to the simultaneous reduction of water on the Ni nuclei growing surfaces. This model allows not only the quantification of the Ni nucleation kinetic parameters but also the effective deconvolution of the individual contributions to the total current; thus, from the integration of the j-t plots of these contributions, it was demonstrated that the charge amount of each process depends on the Ni(II) concentration. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray photoelectron spectroscopy revealed the presence of pure Ni nanoparticles electrodeposited on the electrode surface. Moreover, X-ray measurements verified the formation of a high-crystallinity face-centered cubic structure with preferred orientation growth on the ⟨111⟩ direction, which were also corroborated by the magnetic measurement performed in a physical property measurement system.

The fungicide Tebuconazole induces electromechanical cardiotoxicity in murine heart and human cardiomyocytes derived from induced pluripotent stem cells

Tebuconazole (TEB) is an important fungicide that belongs to the triazole family. It is widely used in agriculture and its use has experienced a tremendous increase in the last decade. The long-term exposure of humans to this pesticide is a real threat because it is stable in water and soil. The association between long-term exposure to TEB and damage of several biological systems, including hepatotoxicity and cardiotoxicity is evident, however, acute toxicological studies to reveal the toxicity of TEB are limited. This research paper addressed the acute exposure of TEB in murine hearts, cardiomyocytes, and human cardiomyocytes derived from an induced pluripotent stem cell (hiPSC-CMs), spelling out TEB’s impact on electromechanical properties of the cardiac tissue. In ex vivo experiments, TEB dose dependently, caused significant electrocardiogram (ECG) remodeling with prolonged PR and QTc interval duration. The TEB was also able to change the action potential waveform in murine cardiomyocytes and hiPSC-CMs. These effects were associated with the ability of the compound to block the L-type calcium current (IC50 = 33.2 ± 7.4 μmol.l−1) and total outward potassium current (IC50 = 5.7 ± 1.5 μmol.l−1). TEB also increased the sodium/calcium exchanger current in its forward and reverse modes. Additionally, sarcomere shortening and calcium transient in isolated cardiomyocytes were enhanced when cells were exposed to TEB at 30 μmol.l−1. Combined, our results demonstrated that acute TEB exposure affects the cardiomyocyte's electro-contractile properties and triggers the appearance of ECG abnormalities.

Abstract P1-10-05: Evidence that body mass index modifies breast tissue collagen peptide response pattern to treatment with the non-steroidal anti-inflammatory drug sulindac

Abstract Background. In observational studies, regular use of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with reduced breast cancer risk and disease recurrence with evidence that the benefit is greater in overweight/obese women. This parallels findings that obesity is associated with an increase in proinflammatory processes with possible effects on the breast stroma and extracellular matrix. Methods. To assess if body mass index (BMI kg/m2) alters breast tissue response to NSAIDs, we conducted exploratory analyses of change in breast tissue collagen-associated peptides following 6 months of treatment with the NSAID sulindac (150 mg bid) by BMI category: normal (18.5-24.9 n=6), overweight (25-29.9 n=14) and obese (≥30 n=11). Samples for this study were non-cancer core needle breast biopsies from postmenopausal women with a history of hormone receptor positive breast cancer enrolled to study sulindac effect on breast tissue biomarkers. At completion, 36 of 50 patients underwent baseline biopsy and 31 had sufficient tissue for paired analyses. Tissue collagen-associated peptides were studied using whole slide tissue imaging mass spectrometry proteomics. Individual peptide signals were normalized to total ion current and mean peak intensity per area across the entire biological specimen were used to generate a score per patient. Change in stroma peptides was evaluated by BMI status using the Wilcoxon matched pairs signed rank test. Unsupervised hierarchical clustering and heatmap visualization were used to assess differential expression of the peaks. Results. Approximately, 550 peptide peaks were found by targeted collagen tissue imaging proteomics. Striking differences in response to sulindac were observed by BMI. In overweight patients, 6 peptides related to COL1A1, COL6A1, COL6A3 and VIM on database matching differed significantly before and after sulindac treatment. Three were also altered in obese women. Two of the peptides overlapped 10 peptide changes identified in unstratified analyses reported in a separate submitted abstract on the main effect of sulindac on tissue collagen. Interestingly, these peptides were not altered in patients with normal BMI. In addition, on study 15 patients experienced a decrease in BMI and 12 experienced an increase. Two collagen peptides showed inverse relationships dependent on change in BMI status during the study. Conclusion. Six-month treatment with the non-selective NSAID sulindac was associated with changes in collagen-associated peptide differently by BMI status and by weight change. Our findings are most consistent with changes in post-translational hydroxylated proline modifications of collagen variation in the triple helical region. Ongoing work may provide insights on inflammation/adiposity-associated inflammation and effects on breast tissue collagen. Citation Format: Denys Rujchanarong, Peggi M. Angel, Alison Stopeck, Christina Preece, Pavani Chalasani, Patricia A. Thompson. Evidence that body mass index modifies breast tissue collagen peptide response pattern to treatment with the non-steroidal anti-inflammatory drug sulindac [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-10-05.

Node Voltage and KCL Model-Based Low Leakage Volatile and Non-Volatile 7T SRAM Cells

The current generation aims for Low power electronic gadgets like cell phones, PDAs, etc. This urged demand is met through adopting low power reduction techniques. These gadgets also demand the presence of cache memories, which are fabricated via Static Random Access Memory (SRAM) Cells. Now the challenge is in designing low leakage SRAM cells by adopting power reduction techniques. The proposed work of 7T based Volatile and Non-Volatile SRAM cell is carried through adopting efficient low power reduction technique referred to as Improved Self Controllable Voltage Level (I-SVL). Proposed 7T SRAM cell is based on Improved Self Controllable Voltage Level (I-SVL) technique which controls the supply voltage in Idle and Non Idle mode of SRAM cell. Also Upper-ISVL and Lower-ISVL supplies the Vdd and Vss as per the requirement there by controlling the leakage power. The proposed I-SVL based 7T Volatile and Non-Volatile is designed and simulated using Cadence Virtuoso spectre tool by using CMOS technology with gpdk 45nm. Proposed work carried is efficient in terms of sub threshold and total leakage currents in comparison with the earlier work. The obtained sub threshold and total leakage current of the proposed volatile 7T SRAM cell based on the I-SVL shows improvements in lower values with existing work by 15% and 32%. Also proposed Non-volatile based I-SVL 7T SRAM cell resulted in lesser sub threshold and total leakage current by an amount of 97% and 93% in comparison with the earlier work. The gate leakage current of proposed Non-volatile 7T SRAM cell resulted in 57% lower value in comparison with the earlier work.