Search results for “Polarization

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6 articles
Energy Conservation Open Access

The Fermi-Pasta-Ulam Quantum Recurrence in The Dynamics of an Elementary Physical Vacuum Cell and The Problem of its Polarization

Feb 2020 DOI 10.14302/issn.2642-3146.jec-20-3179

A model of a Quantum recurrence in the dynamics of an elementary physical vacuum cell within the framework of four coupled Shrodinger equations has been suggested. The model of an elementary vacuum cell shows that a Quantum recurrence which represents the dynamics of virtual transformations in the cell, qualitatively differs from that of Poincare and the Fermi-Pasta-Ulam. Whereas these recurrences develop in time or space, the Quantum recurrence develops in a sequence of Fourier images represented by non exponentially separating functions. The sequence experiences random energy additions but no exponential separation occurs. The Quantum recurrence can be defined as the most frequent array of Fourier images that appear in a certain quantum system during a period of its observation. Different scenarios of the Fourier images sequences interpreted as bosons (electron and positron) and fermions (photons) apearing in the solutions of the model demonstrate that during some periods of its observation they become indistinguishable. The quantum dynamics of every physical vacuum cell depends on the dynamics of many other vacuum cells interacting with it, thus the quasi periodicity (during the period of observation) of the Fourier images recurrence can have infinite periods of time and space and the amplitudes of the Fourier images can vary many orders in their magnitudes. Such recurrence times does not correspond even roughly to the Poincare recurrence time of an isolated macroscopic system. It reminds the behavior of spatially coupled standard mappings with different parameters. The amount of energy in the physical vacuum is infinite but extracting a part of it and converting, it into a time-space form requires a process of periodical transfer of the reversible microscopic system dynamics into that of a macroscopic system. This process can be realized through a resonant interaction between the classical and quantum recurrences developing in these two systems. However, a technical realization of this problem is problematic.

Skeletal Muscle Calcium Channel Mutation R528G: Enhanced Channel Inactivation and Omega-Current at Hyperpolarization Contribute to Hypokalemic Periodic Paralysis.

Jun 2016 DOI 10.14302/issn.2470-5020.jnrt-16-993

Autosomal dominant inherited hypokalemic periodic paralysis (HypoPP) is caused by S4 voltage sensor mutations in skeletal muscle CaV1.1 calcium or NaV1.4 sodium channels. In the present study, a small German family with the known CaV1.1-R528G is described. The phenotype consists of short and infrequent episodes of limb weakness with ictal respiratory and cardiac involvement. There is incomplete penetrance in women, and acetazolamide is beneficial in two patients also taking daily potassium. Expression of the mutation in the GLT mouse muscle cell line revealed accelerated kinetics of inactivation by twofold, a left-shift of the steady-state inactivation curve by 13mV and a reduced recovery from fast inactivation by up to 39%. These changes suggest a stabilization of the inactivated state. Additional significant slowing of activation may support a second open state with differing ion selectivity or decreased activation of calcium-activated potassium channels and thereby contribute to weakness similar to other CaV1.1 mutations. Also, as documented for other HypoPP mutants, we found a hyperpolarization-induced inward guanidinium current of 22nS/nF which can be interpreted as an omega current along the voltage sensor gating pore that leads to a gain- of- function at potentials near the resting membrane potential. This finding can explain the long-lasting depolarizations that are known to lead to paralysis. The omega current is large enough so that a relatively mild hypokalemic trigger of 2.4mM already produces episodes of weakness in vivo.

Diabetic Mouse Delayed Wound Model Following Treatment with the NerveStim™ Neuropathy System

Apr 2026 DOI 10.14302/issn.2640-6403.jtrr-26-6077

Delayed wound healing in diabetes is characterized by impaired angiogenesis, persistent inflammation, extracellular matrix dysregulation, and peripheral neuropathy. A preclinical study was conducted using a diabetic mouse delayed wound model to evaluate the surrounding tissue of a wound, (its periwound) and its tissue responses following treatment with the NerveStim™ Neuropathy System, a combination topical gel and neuromuscular electrical stimulation platform. Periwound tissue was harvested at Day 14 and analyzed using NanoString gene expression profiling. Treated animals demonstrated visibly increased periwound tissue thickness compared to untreated controls. Differential expression analysis identified 76 significantly upregulated and 17 downregulated genes. Upregulated pathways included angiogenesis (Vegfa, Fgf2, Pdgfb, Nos3), neurotrophic signaling (Ngf, Bdnf, Scn9a, Trpv1), macrophage polarization (Arg1, Mrc1, Il10), and extracellular matrix remodeling (Col1a1, Col3a1, Mmp9, Timp1). Downregulation of select pro-inflammatory mediators (Nos2, Mif) was observed. These coordinated transcriptional changes are consistent with activation of reparative immune, neurovascular, and matrix remodeling pathways in diabetic periwound tissue.

Dogonyaro-Leaf-Extract as Inhibitor for Aluminum Corrosion in Acid

Jun 2023 DOI 10.14302/issn.2377-2549.jndc-23-4431

Background of this paper investigates dogonyaro-leaf-extract as inhibitor for aluminum corrosion in 0.3-M hydrochloric acid, and its acceptability as original. In the methods, the extract was analyzed for phytochemicals and corrosion test performed on aluminum sheet before immersion in acid incorporated extract. Electrochemical Impedance Spectroscopy (EIS), tests were performed over frequency of 100 KHz–10 mHz and 10 mV peak to peak perturbation amplitude to obtain the corrosion potential. Tests were run at 30oC ± room temperature in aerated quiescent solutions. In weight loss method, coupons were suspended in aerated solutions before immersion in 20% mixture of sodium hydroxide and zinc dust to stop further corrosion. Morphology of the mirrorlike finished arid surface aluminum was measured with scanning electron microscope SEM. In the results, various phytochemicals were observed; significant effect of incorporating inhibitor on EIS data recorded and optimum extract efficiency was 99.46%, at 10 g/l, 60oC, within 6 hours. This result was validated and 99.3% efficiency obtained. Introduction of extract into acid corrodents caused increase of charge transfer resistance and reduced double layer capacitance. A warm arid clean coupon evolved after SEM test. In conclusion, there was increase in efficiency of inhibition as inhibitor concentration and temperature increased. Similarly, close responses towards the factors for Inhibition occur. Measured polarization showed that extract inhibited both cathodic and anodic reaction processes and thus, is classified as mixed type inhibitor. The investigations thus proved the extract as excellent corrosion inhibitor for aluminum in 0.3-M hydrochloric-acid.

High Rate of Asymptomatic Myocardial Ischemia in HIV Infected Population in Bobo-Dioulasso in Burkina Faso

Nov 2016 DOI 10.14302/issn.2324-7339.jcrhap-16-1271

Introduction The cardiovascular complications have became the 3rd cause of death and the 4th reason for hospitalization of the patients infected by the HIV. The objective of this work was to determine the frequency of asymptomatic myocardial ischemia among patients infected by the HIV receiving antiretroviral therapy. Patients and Methods It was a descriptive cross-sectional study which was conducted in November 2015. The patients infected by HIV1 receiving antiretroviral treatment, with asymptomatic myocardial ischemia were included in the study and they were followed up in the HIV clinic of the in Infectious diseases service of the University Hospital Souro Sanou of Bobo-Dioulasso(CHUSS).. The includes patients benefited from a collection of cardiovascular risk factors, and of two measurements of the blood pressure in a sitting position after 10 minutes of rest and an electrocardiogram 12 derivations after rest. Results A total sample of 123 patients infected by HIV1 was selected, with a median age of 42 years (IQR: 36-50). It was composed of 79% of female. The cardiovascular risk factors found were distributed as follows: HTA (31.7%), obesity (33%), dyslipidemia (10.57%), active smoking (0.8%), diabetes (0.8%). All the known hypertensive cases (5.7%) were insufficiently treated. The median duration of exposure to the antiretroviral therapy was 5.3 years (IIQ: 3-7.7). The disorders of the repolarization were observed in 26 cases (21.13%). They were divided into under epicardic ischemia in 20 cases (16.26%), under endocardic lesion in 2 cases (1.63%) and after-effect of necrosis in 4 cases (3.25%). The Left ventricular hypertrophywas observed in 12 cases (9.76%) and all of them were hypertensive patients. QTc was lengthened among 7 patients (5.69%) independently of the class of antiretroviral therapy administrated. Conclusion In this study about patients infected by HIV1, it emerges that asymptomatic myocardial ischemia is frequent. It would be advisable to reinforce its tracking by using more powerful tests of ischemia, in order to better specify its gravity in this population with an increased cardiovascular risk.  

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