405 research outputs found

    Efficacy of Advanced Prehospital Communication in Acute Ischemic Stroke Treatment

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    Ischemic stroke outcomes are directly affected by time to treatment. This intervention demonstrates promise in decreasing time to treatment by optimizing pres-hospital communication, basically giving a report to providers and registration information before the patient arrives at the facility. The use of an advanced digital application has demonstrated in multiple studies significant difference in time to treatment in ischemic stroke, and ultimately leads to improved patient outcomes, increased staff satisfaction, and increased facility revenue

    Impact of Sports Nutrition Education on Adolescents' Nutritional Knowledge and Use of Ergogenic Products

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    Food Scienc

    Reversed Hofmeister series - the rule rather than the exception

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    Over recent years, the supposedly universal Hofmeister series has been replaced by a diverse spectrum of direct, partially altered and reversed series. This review aims to provide a detailed understanding of the full spectrum by combining results from molecular dynamics simulations, Poisson–Boltzmann theory and AFM experiments. Primary insight into the origin of the Hofmeister series and its reversal is gained from simulation-derived ion–surface interaction potentials at surfaces containing non-polar, polar and charged functional groups for halide anions and alkali cations. In a second step, the detailed microscopic interactions of ions, water and functional surface groups are incorporated into Poisson–Boltzmann theory. This allows us to quantify ion-specific binding affinities to surface groups of varying polarity and charge, and to provide a connection to the experimentally measured long-ranged electrostatic forces that stabilize colloids, proteins and other particles against precipitation. Based on the stabilizing efficiency, the direct Hofmeister series is obtained for negatively charged hydrophobic surfaces. Hofmeister series reversal is induced by changing the sign of the surface charge from negative to positive, by changing the nature of the functional surface groups from hydrophobic to hydrophilic, by increasing the salt concentration, or by changing the pH. The resulting diverse spectrum reflects that alterations of Hofmeister series are the rule rather than the exception and originate from the variation of ion-surface interactions upon changing surface properties

    Location and Conformation of the LK alpha 14 Peptide in Water/Ethanol Mixtures

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    It is widely recognized that solvation is one of the major factors determining structure and functionality of proteins and long peptides, however it is a formidable challenge to address it both experimentally and computationally. For this reason, simple peptides are used to study fundamental aspects of solvation. It is well established that alcohols can change the peptide conformation and tuning of the alcohol content in solution can dramatically affect folding and, as a consequence, the function of the peptide. In this work, we focus on the leucine and lysine based LK alpha 14 peptide designed to adopt an alpha-helical conformation at an apolar-polar interface. We investigate LK alpha 14 peptide's bulk and interfacial behavior in water/ethanol mixtures combining a suite of experimental techniques (namely, circular dichroism and nuclear magnetic resonance spectroscopy for the bulk solution, surface pressure measurements and vibrational sum frequency generation spectroscopy for the air-solution interface) with molecular dynamics simulations. We observe that ethanol highly affects both the peptide location and conformation. At low ethanol content LK alpha 14 lacks a clear secondary structure in bulk and shows a clear preference to reside at the air-solution interface. When the ethanol content in solution increases, the peptide's interfacial affinity is markedly reduced and the peptide approaches a stable alpha-helical conformation in bulk facilitated by the amphiphilic nature of the ethanol molecules

    MONITORING OF EMG TO FORCE RATIO USING NEW DESIGNED PRECISE WIRELESS SENSOR SYSTEM

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    This work is focused on problematic of biopotential signals measurements (EXG) using powerful SMART sensor system, composed of portable units, intended for in-time wireless measurement and evaluation of electrical activity, produced by skeletal muscles, human heart or brain. Here, we discuss very precise measurement features, which characterize this device (high gain, low noise, wireless data transfer, multi-probe measuring), some special features as low voltage and ultra-low power consumption were reached by application of the described amplifier in order to achieve its longer performance for daily use. It brings a lot of advantages to biomedical electronics and medical care. In order to optimize the performance of novel proposed smart biomedical instrument in our experimental part we have focused on measurement of surface electromyography (sEMG) signal to force ratio. These sEMG signals can illuminate our understanding of how the brain controls muscles to generate force and produce movement and can be used in such applications like as training of athletes, controlling robots, monitoring the physical capabilities of patients with motor disorders etc

    Hydration and self-​aggregation of a neutral cosolute from dielectric relaxation spectroscopy and MD simulations: the case of 1,​3-​dimethylurea

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    The influence of the amphiphile 1,3-dimethylurea (1,3-DMU) on the dynamic properties of water was studied using dielec. relaxation spectroscopy. The expt. provided evidence for substantial retardation of water reorientation in the hydration shell of 1,3-DMU, leading to a sep. slow-water relaxation in addn. to contributions from bulk-like and fast water as well as from the solute. From the amplitudes of the resolved water modes effective hydration nos. were calcd., showing that each 1,3-DMU mol. effectively freezes the reorientation of 1-2 water mols. Addnl., a significant amt. of solvent mols., decreasing from ~39 at infinite diln. to ~3 close to the soly. limit, is retarded by a factor of ~1.4 to 2.3, depending on concn. The marked increase of the solute amplitude indicates pronounced parallel dipole alignment between 1,3-DMU and its strongly bound H2O mols. Mol. dynamics (MD) simulations of selected solns. revealed a notable slowdown of water rotation for those solvent mols. surrounding the Me groups of 1,3-DMU and strong binding of ~2H2O by the hydrophilic carbonyl group, corroborating thus the exptl. results. Addnl., the simulations revealed 1,3-DMU self-aggregates of substantial lifetime

    消化器内科この一年

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    © the Owner Societies 2017.The influence of the amphiphile 1,3-dimethylurea (1,3-DMU) on the dynamic properties of water was studied using dielectric relaxation spectroscopy. The experiment provided evidence for substantial retardation of water reorientation in the hydration shell of 1,3-DMU, leading to a separate slow-water relaxation in addition to contributions from bulk-like and fast water as well as from the solute. From the amplitudes of the resolved water modes effective hydration numbers were calculated, showing that each 1,3-DMU molecule effectively freezes the reorientation of 1-2 water molecules. Additionally, a significant amount of solvent molecules, decreasing from ∼39 at infinite dilution to ∼3 close to the solubility limit, is retarded by a factor of ∼1.4 to 2.3, depending on concentration. The marked increase of the solute amplitude indicates pronounced parallel dipole alignment between 1,3-DMU and its strongly bound H2O molecules. Molecular dynamics (MD) simulations of selected solutions revealed a notable slowdown of water rotation for those solvent molecules surrounding the methyl groups of 1,3-DMU and strong binding of ∼2H2O by the hydrophilic carbonyl group, corroborating thus the experimental results. Additionally, the simulations revealed 1,3-DMU self-aggregates of substantial lifetime

    Hydration and self-aggregation of a neutral cosolute from dielectric relaxation spectroscopy and MD simulations: The case of 1,3-dimethylurea

    Get PDF
    © the Owner Societies 2017.The influence of the amphiphile 1,3-dimethylurea (1,3-DMU) on the dynamic properties of water was studied using dielectric relaxation spectroscopy. The experiment provided evidence for substantial retardation of water reorientation in the hydration shell of 1,3-DMU, leading to a separate slow-water relaxation in addition to contributions from bulk-like and fast water as well as from the solute. From the amplitudes of the resolved water modes effective hydration numbers were calculated, showing that each 1,3-DMU molecule effectively freezes the reorientation of 1-2 water molecules. Additionally, a significant amount of solvent molecules, decreasing from ∼39 at infinite dilution to ∼3 close to the solubility limit, is retarded by a factor of ∼1.4 to 2.3, depending on concentration. The marked increase of the solute amplitude indicates pronounced parallel dipole alignment between 1,3-DMU and its strongly bound H2O molecules. Molecular dynamics (MD) simulations of selected solutions revealed a notable slowdown of water rotation for those solvent molecules surrounding the methyl groups of 1,3-DMU and strong binding of ∼2H2O by the hydrophilic carbonyl group, corroborating thus the experimental results. Additionally, the simulations revealed 1,3-DMU self-aggregates of substantial lifetime

    APPLICATION OF SINGLE WIRELESS HOLTER TO SIMULTANEOUS EMG, MMG AND EIM MEASUREMENT OF HUMAN MUSCLES ACTIVITY

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    This paper describes application and design of wireless holter with innovative functionality, used it in field of human muscle monitoring. In our experiments we monitored EMG (electromyography), MMG (mechanomyography) and EIM (electrical impedance myography) all by single device. It is first time when these all parameters were monitored simultaneously taking advantage of the holter device data output in order to find the signals interconnection. Our data were compared with normally used medical device and signal quality was verified
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