Search results for "hydration"

Cationic and Anionic Impact on the Electronic Structure of Liquid Water

2017

Hydration shells around ions are crucial for many fundamental biological and chemical processes. Their local physicochemical properties are quite different from those of bulk water and hard to probe experimentally. We address this problem by combining soft X-ray spectroscopy using a liquid jet and molecular dynamics (MD) simulations together with ab initio electronic structure calculations to elucidate the water–ion interaction in a MgCl2 solution at the molecular level. Our results reveal that salt ions mainly affect the electronic properties of water molecules in close vicinity and that the oxygen K-edge X-ray emission spectrum of water molecules in the first solvation shell differs signi…

Dietary water seems to improve skin hydration without influencing hemodynamics

2013

The various studies on the importance of water in the hydration of human skin have suggested that an increased dietary intake might positively impact the physiology of normal skin. We evaluated the consequences of increasing water intake through drinking in skin hydration in vivo. Eating habits were maintained, evaluated by a Food Frequency Questionnaire and based on total water consumption. In two groups with different total water consumption, we evaluated the impact of 2L/day water after 30 days,. This increase produced no hemodynamic changes or weight changes but an improvement in the epidermal hydration was suggested. The magnitude of the impact on skin hydration was higher in the group…

Hydration dependence of myoglobin dynamics studied with elastic neutron scattering, differential scanning calorimetry and broadband dielectric spectr…

2014

In this work we present a thorough investigation of the hydration dependence of myoglobin dynamics. The study is performed on D2O-hydrated protein powders in the hydration range 0<h<0.5 (h≡gr[D2O]/gr[protein]) and in the temperature range 20-300K. The protein equilibrium fluctuations are investigated with Elastic Neutron Scattering using the spectrometer IN13 at ILL (Grenoble), while the relaxations of the protein + hydration water system are investigated with Broadband Dielectric Spectroscopy; finally, Differential Scanning Calorimetry is used to obtain a thermodynamic description of the system. The effect of increasing hydration is to speed up the relaxations of the myoglobin + hydration …

Comparison of a near-infrared reflectance spectroscopy system and skin conductance measurements for in vivo estimation of skin hydration: a clinical …

2017

Diffuse reflectance spectroscopy system was developed for estimation of skin hydration in the near-infrared spectral range of 900-1700 nm. Experimental setup consisted of a near-infrared spectrometer, Y-type fiber optics probe with 1 detection and 6 illumination fibers, halogen-tungsten light source and a PC. By analyzing diffuse reflectance spectrum, a parameter representing skin hydration by performing baseline correction and calculating the area under the 1450 nm water absorption maximum is proposed. A clinical study was performed acquiring data of skin hydration of 39 patients' forearm skin. Results of the developed system are compared to results obtained by a commercial device based on…

3D MICROSIZED PROTEIN AMYLOID PARTICULATES AS EFFECTIVE BIOADSORBERS FOR Pb2+ IONS

The production of new cost-effective biocompatible sorbent sustainable materials, with natural origins, able to remove heavy metals from water resources is nowadays highly desirable in order to reduce pollution and increase clean water availability. In this context, self-assembled protein materials with highly ordered amyloid structures, stabilised by H-bonds, seems to have a great potential as natural platform for a broader development of highly-tunable structures. By suitably varying solution conditions it is possible to tune aggregate size, surface area and morphologies as well as their physicochemical (hydrophobicity, hydrophilicity, swelling/deswelling properties) and mechanical proper…

Influence of Manual Therapies in Lumbar Disc Herniation A Case Study

2017

Magnetic Resonance Imaging (MRI) has so far been the best way to diagnose disc herniation, the high resolution of images taken on various vertebral tissues allowing the observation, in different planes, of situations such as: the displacement of dural sac and nerve roots, the disc hydration status, which are important data forthe diagnosis and prognosis of disc disease.Manual therapies mainly aim at restoring the lost joint mobility, but also the balance of muscular, skeletal and cranial systems. To this purpose, manipulationtechniques are used for decompression ofthe nerve root affected by disc herniation, spinal hypomobilityandnormalisation ofthe muscles that are peripheral to the lesion.…

Effects of three different water temperatures on dehydration in competitive swimmers

2011

Summary Aims The purpose of this study was to evaluate the effects of three different water temperatures on physiological responses (dehydration, sweat rate, urine output, rectal temperature and plasma electrolytes) of competitive athletes during a “simulated” race of 5 km in an indoor swimming pool. Methods Nine male competitive master swimmers swam 5 km with the water at temperatures of 23, 27 and 32 C. Immediately before (Pre) and after (Post) each trial, samples of blood and urine were collected, body weight was recorded and rectal temperature was measured. The dehydration percentage and sweat rate were the highest at 32 C and the lowest at 23 C (23 C: −0.9 ± 0.5; 27 C: −1.3 ± 0.6; 32 C…

Dynamic in vitro dehydration patterns of unworn and worn silicone hydrogel contact lenses.

2008

Purpose: To evaluate the effect of wear on dynamic in vitro dehydration of silicone hydrogel (Si-Hi) contact lens (CL) using a previously described gravimetric procedure. Methods: Five different silicone hydrogel (Si-Hi) contact lenses (CL) were evaluated after being worn by patients under daily wear conditions for 15 days to 1 month. Lenses were conditioned and disinfected with a multipurpose solution after each day of wear. Lenses were left to dehydrate in an analytical balance under controlled conditions of temperature and relative humidity and the results compared with data from new lens samples of the same power and material. Several quantitative parameters were obtained and compared b…

Corrected whole blood biomarkers - the equation of Dill and Costill revisited.

2018

Abstract An exercise bout or a dehydration often causes a reduction in plasma volume, which should be acknowledged when considering the change in biomarkers before and after the plasma changing event. The classic equation from Dill and Costill (1974, J. Appl. Physiol., 37, 247–248) for plasma volume shift is usually utilized in such a case. Although this works well with plasma and serum biomarkers, we argue in this note that this traditional approach gives misleading results in the context of whole blood biomarkers, such as lactate, white cells, and thrombocytes. In this study, we demonstrate that to calculate the change in the total amount of circulating whole blood biomarker, one should u…

Muscle cramping in the marathon: dehydration and electrolyte depletion vs. muscle damage

2020

Martinez-Navarro, I, Montoya-Vieco, A, Collado, E, Hernando, B, Panizo, N, and Hernando, C. Muscle Cramping in the marathon: Dehydration and electrolyte depletion vs. muscle damage. J Strength Cond Res XX(X): 000-000, 2020-Our aim was to compare dehydration variables, serum electrolytes, and muscle damage serum markers between runners who suffered exercise-associated muscle cramps (EAMC) and runners who did not suffer EAMC in a road marathon. We were also interested in analyzing race pacing and training background. Nighty-eight marathoners took part in the study. Subjects were subjected to a cardiopulmonary exercise test. Before and after the race, blood and urine samples were collected and…