Effect of Heat Acclimation on Lactate Excretion Rate and Sodium Ion Reabsorption Rate during Exercise

The purpose of this study was to determine the effect of active heat acclimation on the sweat osmolality and sweat sodium ion concentration vs. sweat rate relationship in humans. Eight healthy male volunteers completed 10 days of exercise in the heat. The mean exercising heart rate and core temperature were significantly decreased ( P < 0.05) by 18 beats/min and 0.6°C, respectively, following heat acclimation. Furthermore, sweat osmolality and the sweat sodium ion concentration vs. sweat rate relationships were shifted to the right. Specifically, the slopes of the relationships were not affected by heat acclimation. Rather, heat acclimation significantly reduced the y-intercepts of the sweat osmolality and sweat sodium relationships with sweat rate by 28 mosmol/kgH2O and 15 mmol/l, respectively. Thus there was a significantly lower sweat sodium ion concentration for a given sweat rate following heat acclimation. These results suggest that heat acclimation increases the sodium ion reabsorption capacity of the human eccrine sweat gland.

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The relationship between exercise intensity and the sweat lactate excretion rate

The Journal of Physiological Sciences ◽

10.1007/s12576-009-0073-3 ◽

2009 ◽

Vol 60 (2) ◽

pp. 103-107 ◽

Cited By ~ 48

Author(s):

Michael J. Buono ◽

Nanette V. L. Lee ◽

Paul W. Miller

Keyword(s):

Exercise Intensity ◽

Excretion Rate ◽

The Relationship ◽

Sweat Lactate ◽

Lactate Excretion

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CuS2 sheets: a hidden anode material with a high capacity for sodium-ion batteries

Journal of Materials Chemistry C ◽

10.1039/d0tc04946h ◽

2021 ◽

Author(s):

Shaohua Lu ◽

Weidong Hu ◽

Xiaojun Hu

Keyword(s):

Lithium Ion Batteries ◽

Anode Material ◽

Low Cost ◽

High Capacity ◽

Lithium Ion ◽

Sodium Ion ◽

Sodium Ion Batteries

Due to their low cost and improved safety compared to lithium-ion batteries, sodium-ion batteries have attracted worldwide attention in recent decades.

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Abstract #200: The Relationship Between Albumin Excretion Rate and Estimated Glomerular Filtration Rate in Nigerian Patients with Type 2 Diabetes Mellitus

Endocrine Practice ◽

10.1016/s1530-891x(20)42506-6 ◽

2015 ◽

Vol 21 ◽

pp. 23

Author(s):

Orighomisan Agboghoroma ◽

Fabian Puepet ◽

Gabriel Odoh ◽

Marcelina Enamino ◽

Jones Uwakwe ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Glomerular Filtration Rate ◽

Filtration Rate ◽

Estimated Glomerular Filtration Rate ◽

Excretion Rate ◽

Albumin Excretion Rate ◽

The Relationship

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Basic Studies of Various 99mTc-Labelled Renal Agents and Clinical Application of 99mTc-Malate

Nuklearmedizin ◽

10.1055/s-0037-1620604 ◽

1977 ◽

Vol 16 (01) ◽

pp. 36-41 ◽

Cited By ~ 1

Author(s):

T. Machida ◽

M. Miki ◽

M. Ueda ◽

A. Tanaka ◽

I. Ikeda

Keyword(s):

Excretion Rate ◽

Animal Experiments ◽

Imaging Agents ◽

Half Time ◽

Clinical Experiences ◽

Labelling Efficiency ◽

Urinary Excretion Rate ◽

Renal Imaging ◽

The Past ◽

Basic Studies

SummaryVarious renal imaging agents that were reported in the past and a new agent, 99mTc-malate as well as 99mTc-cystein acetazolamide complex were prepared using electrolysis and electrochemical methods. These were studied for their labelling efficiency. After animal experiments with selected 99mTc-com- pounds, 99mTc-rnalate proved to be sufficient for renal imaging with adequate concentration. 99mTcmalate differs from other renal imaging agents in the utilization of endogeneous metabolic product.The first half time of 99mTc-malate in humans is 17 minutes, on the average, and the urinary excretion rate of 99mTc-malate is 36±6.05% in 1 hour after intravenous administration, 44 ± 3.41% in 2 hours and 50 + 5.62% in 3 hours.In our 40 clinical experiences of 99m-Tc-rnalate, most cases demonstrated quite clear renal images in the serial scintiphotos except cases whose serum creatinines were over 4.5 mg/dl.

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Under Pressure: Mechanochemical Effects on Structure and Ion Conduction in the Sodium-Ion Solid Electrolyte Na3PS4

10.26434/chemrxiv.12477776.v1 ◽

2020 ◽

Author(s):

Theodosios Famprikis ◽

O. Ulas Kudu ◽

James Dawson ◽

Pieremanuele Canepa ◽

François Fauth ◽

...

Keyword(s):

Ionic Conductivity ◽

Mechanochemical Synthesis ◽

Activation Volume ◽

External Pressure ◽

Sodium Ion ◽

Variable Pressure ◽

Ion Conductor ◽

Ceramic Synthesis ◽

Solid State Batteries ◽

Fast Ion

<div> Fast-ion conductors are critical to the development of solid-state batteries. The effects of mechanochemical synthesis that lead to increased ionic conductivity in an archetypical sodium-ion conductor Na3PS4 are not fully understood. We present here a comprehensive analysis based on diffraction (Bragg, pair distribution function), spectroscopy (impedance, Raman, NMR, INS) and ab-initio simulations aimed at elucidating the synthesis-property relationships in Na3PS4. We consolidate previously reported interpretations about the local structure of ball-milled samples, underlining the sodium disorder and showing that a local tetragonal framework more accurately describes the structure than the originally proposed cubic one. Through variable-pressure impedance spectroscopy measurements, we report for the first time the activation volume for Na+ migration in Na3PS4, which is ~30% higher for the ball-milled samples. Moreover, we show that the effect of ball-milling on increasing the ionic conductivity of Na3PS4 to ~10-4 S/cm can be reproduced by applying external pressure on a sample from conventional high temperature ceramic synthesis. We conclude that the key effects of mechanochemical synthesis on the properties of solid electrolytes can be analyzed and understood in terms of pressure, strain and activation volume. </div>

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Exploring the Influence of Substitution on the Structure and Transport Properties in the Sodium Superionic Conductor Na11+xSn2+x(Sb1−yPy)1−xS12

10.26434/chemrxiv.12278237.v1 ◽

2020 ◽

Author(s):

Marvin Kraft ◽

Lara Gronych ◽

Theodosios Famprikis ◽

Saneyuki Ohno ◽

Wolfgang Zeier

Keyword(s):

Electrochemical Impedance ◽

Structural Phase ◽

Ionic Transport ◽

Sodium Ion ◽

Ionic Conductors ◽

Temperature Dependent ◽

Activation Barriers ◽

Rietveld Refinements ◽

High Performing ◽

The Given

Sulfidic sodium ion conductors are currently investigated for the possible use in all-solid-state sodium ion batteries. The design of high performing electrolytes in terms of temperature-dependent ionic transport is based upon the fundamental understanding of structure – transport relationships within the given structural phase boundaries inherent to the investigated materials class. In this work, the Na+ superionic structural family of Na11Sn2PS12 is explored by using the systematic antimony substitution with phosphorous in Na11+xSn2+x(Sb1-yPy)1-xS12. A combination of Rietveld refinements against X-ray synchrotron diffraction data with electrochemical impedance spectroscopy is used to monitor the changes in the anionic framework, the Na+ substructure and the ionic transport. A new simplified descriptor for the average Na+ diffusion pathways, the average Na+ polyhedral volume is introduced, which is used to correlate the contraction of the overall lattice and the found activation barriers in the system. This study exemplifies how substitution affects diffusion pathways in ionic conductors and widens the knowledge about the related structural motifs and their influence on the ionic transport in this novel class of ionic conductors.

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Defect-Mediated Conductivity Enhancements in Na3-xPn1-xWxS4 (Pn = P, Sb) using Aliovalent Substitutions

10.26434/chemrxiv.9943961.v2 ◽

2019 ◽

Author(s):

Till Fuchs ◽

Sean Culver ◽

Paul Till ◽

Wolfgang Zeier

Keyword(s):

Ionic Conductivity ◽

Vacancy Concentration ◽

Sodium Ion ◽

High Ionic Conductivity ◽

Ionic Conductors ◽

X Ray Diffraction ◽

X Ray ◽

Solid State Batteries ◽

Ion Conducting ◽

Very High

The sodium-ion conducting family of Na3PnS4, with Pn = P, Sb, have gained interest for the use in solid-state batteries due to their high ionic conductivity. However, significant improvements to the conductivity have been hampered by the lack of aliovalent dopants that can introduce vacancies into the structure. Inspired by the need for vacancy introduction into Na3PnS4, the solid solutions with WS42- introduction are explored. The influence of the substitution with WS42- for PS43- and SbS43-, respectively, is monitored using a combination of X-ray diffraction, Raman and impedance spectroscopy. With increasing vacancy concentration improvements resulting in a very high ionic conductivity of 13 ± 3 mS·cm-1 for Na2.9P0.9W0.1S4 and 41 ± 8 mS·cm-1 for Na2.9Sb0.9W0.1S4 can be observed. This work acts as a stepping-stone towards further engineering of ionic conductors using vacancy-injection via aliovalent substituents.

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