Hydration state

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The effect of hydration state and energy balance on innate immunity of a desert reptile

The effect of hydration state and energy balance on innate immunity of a desert reptile

Dilution trials were conducted to test whether any dif- ferences in immune function due to hydration state of the animal could be explained purely by plasma osmolal- ity during assaying. An initial 0.15 ml blood sample was collected from four laboratory animals for osmolality and lysis and agglutination analyses. Animals were held without food or water, and body masses were closely monitored as a rough indicator of water loss (since en- ergy loss over this time would be minimal). Additionally, blood samples (0.07 ml) were taken twice per week to monitor plasma osmolality. Once an animal had lost 15% of its initial body mass or had reached a plasma osmolality of over 320 mOsm (reaching moderate to se- vere dehydration according to clinical signs shown by some Gila monsters in this hydration state), a final 0.15 ml blood sample was collected from the animal. An ali- quot of plasma (60 μl, with the exception of one 30 μl aliquot from a sample that required a repeated osmolal- ity analysis) from each of these dehydrated state samples was then diluted with nanopure water (5 to 15 μl) to generate a sample from a dehydrated animal but with an osmolality similar to that of the animal’s plasma when in a hydrated state. We used the initial hydrated (20 μl plasma), the dehydrated (20 μl plasma), and the diluted dehydrated (15.4-16.8 μl plasma with 3.2-4.6 μl nanopure to make 20 μl total) samples from each individual to com- pare osmolality, lysis, and agglutination.

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Effects of the hydration state on the mid infrared spectra of urea and creatinine in relation to urine analyses

Effects of the hydration state on the mid infrared spectra of urea and creatinine in relation to urine analyses

When analyzing solutes by Fourier transform infrared (FT-IR) spectroscopy in attenuated total reflection (ATR) mode, drying of samples onto the ATR crystal surface can greatly increase solute band intensities and, therefore, aid detection of minor components. However, analysis of such spectra is complicated by the existence of alternative partial hydration states of some substances that can significantly alter their infrared signatures. This is illustrated here with urea, which is a dominant component of urine. The effects of hydration state on its infrared spectrum were investigated both by incubation in atmospheres of fixed relative humidities and by recording serial spectra during the drying process. Significant changes of absorption band positions and shapes were observed. Decomposition of the CN antisymmetric stretching (n as ) band in all

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Association of plasma adiponectin levels with cellular hydration state measured using bioelectrical impedance analysis in patients with COPD

Association of plasma adiponectin levels with cellular hydration state measured using bioelectrical impedance analysis in patients with COPD

independent, significant parameter contributing to increase in body weight after nutritional therapy. A tendency towards a higher ECW/ICW ratio was observed in patients who failed to respond to nutritional support. This finding is consistent with our hypothesis. It is plausible that cellular metabolic changes by reduced plasma adiponectin levels can induce cellular shrinkage and/or such cellular shrink- age might inhibit cellular anabolic process in parallel with the reduced actions of adiponectin. Thus, this data revealed that cellular shrinkage may represent disadvantages for the development and maintenance of individual cells and tissues through nutritional support and hormonal activities. Mea- suring cellular hydration state not only allows evaluation of anabolic processes, but also the integrated effect by other various hormonal and metabolic responses to adiponectin at a cellular level.

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Discontinuous gas exchange cycle characteristics are differentially affected by hydration state and energy metabolism in gregarious and solitary desert locusts

Discontinuous gas exchange cycle characteristics are differentially affected by hydration state and energy metabolism in gregarious and solitary desert locusts

expected to be lower in the hydrated state, when haemolymph volume is twofold higher and its ionic strength is lower (Fig. 4B). The impact of proteins on haemolymph buffering depends on their concentration and composition, both of which could vary with insect age, sex, diet and nutritional status. In addition, given the wide range of phase-specific physiological variation, we cannot rule out the possibility that haemolymph proteins in solitary and gregarious locusts vary in composition too. Literature data on the specific buffer value of haemolymph proteins is based on haemolymph of female S. gregaria, 3 – 4 weeks after adult eclosion (Harrison et al., 1990), whereas males were used in the present study. Sex-specific variation in haemolymph amino acid composition has been reported for young adult S. gregaria (Benassi et al., 1961). Interestingly, the haemolymph of males was reported to exhibit a considerably higher concentration of histidine, the imidazole groups of which have pKa values of 7 – 8 and thus provide most of the buffering capacity at physiologically relevant pH values (Truchot, 1987). We therefore refrained from attempting to quantify the extent of the link between haemolymph protein content and CO 2

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Rapid adaptive response to a Mediterranean environment reduces phenotypic mismatch in a recent amphibian invader

Rapid adaptive response to a Mediterranean environment reduces phenotypic mismatch in a recent amphibian invader

As reported in other species of amphibians (Titon et al., 2010; Tingley et al., 2012; Kosmala et al., 2017), guttural toad locomotor performance is affected by hydration state (Table 1); this implies that in the invaded range, the capacity of the species to disperse and migrate during the breeding season is constrained by the hot, dry Mediterranean summers. Invasive toads are exposed to desiccating conditions that make the phenotype of the species sub-optimal in the invaded area, thus causing a phenotypic mismatch. We show that invasive toads may be responding to these constraints (1) through behavioural means (adopting a more effective water-conserving posture) and (2) by balancing high rates of EWL with fast WU. However, our study also shows that individuals from the invaded range notably, but not significantly, outperformed native conspecifics when dehydrated; for example, endurance of invasive toads was about twice that of native toads in both dehydration treatments (Fig. 4A; Dataset 1). Conversely, native toads had slightly higher endurance than invasive toads when fully hydrated (Fig. 4). This contrast could suggest a trade-off in performance, such that enhanced performance when dehydrated has come at the cost to performance when hydrated (Kosmala et al., 2017). Given the striking difference in sensitivity of locomotion to hydration state between the two populations, the lack of statistical power in our analysis (Table 1) is probably due to sample size constraints and wide inter-individual variation in locomotor ability (Fig. 4); although logistic constraints did not allow us to test endurance in a larger number of individuals, increasing the sample size in future studies may reveal significant differences between toads in native and invaded ranges as recently observed in the cane toad (Kosmala et al., 2017).

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Milk: An Alternative Beverage for  Hydration?

Milk: An Alternative Beverage for Hydration?

hydration. These studies suggested that the use of milk in the post exercise can help to replace fluids and pro- mote the hydration. Despite the benefits regarding the intake of milk in post-exercise, it should be pointed out that some individuals have hypolactasia/alactasia, allergy to milk proteins or some other intolerance that pre- vents its consumption. In this case, are recommended to ingest alternative drinks rather than milk-based drinks to restore the normal physiological hydration state in the post-exercise [4]. For individuals with hypolactasia di- agnosis, may be prescribed the lactose-free milk [39] as an alternative. Lactose-free milk was described as good recovery drink when compared to water and sports drink [40]. However, there are no studies that compared the effects of this type of milk on post-exercise hydration.

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Moisturizing and antiinflammatory properties of cosmetic formulations containing Centella asiatica extract

Moisturizing and antiinflammatory properties of cosmetic formulations containing Centella asiatica extract

Centella asiatica extract is a rich source of natural bioactive substances, triterpenoid saponins, flavonoids, phenolic acids, triterpenic steroids, amino acids and sugars. Thus, many scavenging free radicals, exhibit antiinflammatory activity and affect on the stratum corneum hydration and epidermal barrier function. The aim of the present study was to evaluate the in vivo moisturizing and antiinflammatory properties of cosmetic formulations (oil-in-water emulsion cream and hydrogel) containing different concentrations of Centella asiatica extract. The study was conducted over four weeks on a group of 25 volunteers after twice a day application of cosmetic formulations with Centella asiatica extract (2.5 and 5%, w/w) on their forearms. The measurement of basic skin parameters (stratum corneum hydration and epidermal barrier function) was performed once a week. The in vivo antiinflammatory activity based on the methyl nicotinate model of microinflammation in human skin was evaluated after four weeks application of tested formulations. In vivo tests formulations containing 5% of Centella asiatica extract showed the best efficacy in improving skin moisture by increase of skin surface hydration state and decrease in transepidermal water loss as well as exhibited antiinflammatory properties based on the methyl nicotinate model of microinflammation in human skin. Comparative tests conducted by corneometer, tewameter and chromameter showed that cosmetic formulations containing Centella asiatica extract have the moisturizing and antiinflammatory properties.

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Estimating hydration changes upon biomolecular reactions from osmotic stress, high pressure, and preferential hydration experiments

Estimating hydration changes upon biomolecular reactions from osmotic stress, high pressure, and preferential hydration experiments

number of water molecules adsorbed or released from biomol- ecules as a result of a biochemical process such as binding and allosteric effects? Volumetric and osmotic stress analyses are es- tablished methods for estimating water numbers; however, these techniques often yield conflicting results. In contrast, Kirkwood– Buff theory offers a novel way to calculate excess hydration number from volumetric data, provides a quantitative condition to gauge the accuracy of osmotic stress analysis, and clarifies the relationship between osmotic and volumetric analyses. I have applied Kirkwood–Buff theory to calculate water numbers for two processes: (i) the allosteric transition of hemoglobin and (ii) the binding of camphor to cytochrome P450. I show that osmotic stress analysis may overestimate hydration number changes for these processes.

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Hydrophysical properties and Hydration Efficiency of Traditional and Alternative Greenhouse Substrate Components.

Hydrophysical properties and Hydration Efficiency of Traditional and Alternative Greenhouse Substrate Components.

Wettability of a material has been defined by Letey et al. (1962) as the ability of a liquid to spread over a surface. Proper wettability ensures even distribution of water and therefor nutrients throughout the entirety of the substrate. Appropriate wettability also leads to greater water holding capacity, which has been shown to be an important factor for proper plant growth (Plaut et al., 1973). Horticultural substrates often have wettability problems due to the high percentage of organic matter (OM) components in them. The OM in substrates, primarily being of sphagnum peat moss and pine bark, can become hydrophobic, thus creating a lack of wettability (Dekker et al., 2000a). The organic molecules of OM contain many organic acid functional groups on their exterior, which include carboxylic acids and phenolic acids, among others. These acidic functional groups tend to repel water from the particle surfaces when in a neutral state with hydrogen cations bound to oxygen anions (Ellerbrock et al., 2005). When allowed to air dry these hydrophobic properties of the OM, such as peat, can be intensified and the wetting and rewetting process can be complicated during plant culture (Valat et al., 1991). When allowed to dry out many organic substrates can develop hydrophobicity issues that hinder proper rewetting (Beardsell and Nichols, 1982).

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Mutation of Aquaporin Gene PIP2;5 Postpones Pollen Hydration in Arabidopsis

Mutation of Aquaporin Gene PIP2;5 Postpones Pollen Hydration in Arabidopsis

Pollen grains were considered to be fully hydrated when the width remained constant for 10 min. We determined the hydration completion time for pollen from wild type and the pip2;5 mutant on stigmas of the pip2;5 mutant and wild type. First, when wild type and pip2;5 pollen grains were placed on a wild type stigma, the hydration completion time show no difference between the wild type and pip2;5 pollen grains (data not showed). Next, the pollen grains were placed on wild type and pip2;5 stigmas. Wild type pollen initiated hydration rapidly following it contact with on the wild type stigma (hydration completed by 9.5 ± 2.7 min after pollination. n = 61, Figure 2), however the pollen showed a severe delay in the completion of hydration on the pip2;5 stigma (12.8 ± 5.2 min to complete hydration, n = 61, P<<0.01; Figure 2). By 12 min after pollination, 92% of wild type pollen grains had completed hydration on the wild type stigma, whereas only 36% had completed hydration on the stigma of the pip2;5 mutant. The results suggest that pollen hydration is postponed on the pip2;5 stigma.

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Effects of a Fruit and Vegetable Sports Drink on Hydration and Oxidative Stress Recovery of Brazilian Professional Athletes

Effects of a Fruit and Vegetable Sports Drink on Hydration and Oxidative Stress Recovery of Brazilian Professional Athletes

To ensure a correct evaluation of the hydration status, the athletes received no orientation on pre-exercise hydration. At all steps, the athletes performed 60 minutes of aerobic exercises, with brief moments of anaerobic activity specific to their sports, considering competition preparation. There was no intervention into how the activities were usually carried out. Thus, intervention into the hydration of athletes was performed considering only the actual needs of each athlete for each sport during the training session. Immediately before and after each training, they were analyzed using the Electro Sensor Complex [15]. The interval between sessions was 5 to 7 days.

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Carbonation of Portland Cement Studied by Diffuse Reflection Fourier Transform Infrared Spectroscopy

Carbonation of Portland Cement Studied by Diffuse Reflection Fourier Transform Infrared Spectroscopy

The total amount of carbonates produced appears to increase for longer hydration durations, as indicated by the convergence limit of the curves in Fig. 3. At these experi- mental conditions it must therefore be easier for the carbon dioxide to react with the calcium in the hydrated cement than the calcium in the unhydrated clinker for short hydration times. This is reasonable, as the clinker is much denser and thus less accessible than the early formed hydration prod- ucts. The absolute amount of carbonates formed was not determined. However, an estimate was made by integrating

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Slag Hydration in composite cements

Slag Hydration in composite cements

The hydration products were investigated by TG, and XRD. The results obtained are shown in Figures 6-7. DTG and XRD confirm the existence of ettringite (AFt) after one day of hydration in all samples. Figure 3 (A-C) shows that, the addition of 10% limestone increased the amount of C-S-H and AFt formed. This effect was greatest at early age. Also noteworthy is the absence of carboaluminate in C2S1-10L at 1 day (from both DTG and XRD). This has been attributed to slower dissolution of carbonates compared to sulphates. However, hemi- carboaluminates are observed in C2 and C2S1 suggesting a different mechanism may be responsible. With a constant 3% calcium sulphate in samples, a slightly higher effective SO 3 /Al 2 O 3 ratio

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A study of the relationship between water and anions of the Hofmeister series using pressure perturbation calorimetry

A study of the relationship between water and anions of the Hofmeister series using pressure perturbation calorimetry

endothermic can be interpreted as the hydration layer weaken- ing or breaking more hydrogen bonds relative to pure water. The temperature where this transition between bond formation and bond breaking is observed is dependent on charge density of the anion. This is clearly seen for the halides which are simple spheres but the general trend is also evident with the more complex structure of the oxoanions and thiocyanate (which is more linear than spherical). It is possible that PPC is providing evidence about the hydrogen bond population of water around the anions. Electrostatic interaction impact on the hydration layer is also evident as valency of the anion has an obvious effect on the average gradient on the DQ versus temperature plot though this work does not differentiate between this being driven by the valency of the anion or the number of sodium ions present.

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Swelling studies of camel and bovine corneal stroma

Swelling studies of camel and bovine corneal stroma

We carried out 20-minute and 46-hour swelling studies on camel and bovine cornea. The 20-minute study was undertaken to assess the affinity of the different ionic solutions described above towards the corneal swelling. The 46-hour study was carried out in order to make a direct comparison of free swelling characteristics between camel and bovine corneal stroma. Additionally, a 14-hour study was carried out to assess leaching out of proteoglycans from the stroma to the bathing solutions. The difference between hydration and rehydration of the corneal stroma will be the leaching out of PGs from the stroma to the bathing solutions.

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FORMULATION AND EVALUATION OF LIPOSOMES OF FENOFIBRATE PREPARED BY THIN FILM HYDRATION TECHNIQUE

FORMULATION AND EVALUATION OF LIPOSOMES OF FENOFIBRATE PREPARED BY THIN FILM HYDRATION TECHNIQUE

Effect of the Process Parameters on the % Drug Loading: Liposome drug loading is described as the percentage of drug entrapped in comparison to the lipid utilized (drug to lipid ratio). Drug loading is a challenge for hydrophilic drugs compared to hydrophobic drugs. By increment in drug concentration the drug loading can be enhanced for hydrophilic drug. As observed from Fig. 8 and 9, drug loading is between 90 to 110% when hydration time is 17 to 42 min and all hydration volume and drug loading is 90 to 110% with every Drug: lecithin Ratio and increasing hydration time till 30 min. As drug: lecithin ratio decreases (0.1:2) and hydration volume increases it shows less drug loading. Data suggested the % drug loading ranges from 90 - 110% with drug: lecithin ratio greater than 2 and sonication time and the % drug loading is 90 - 110% with sonication time ranging from 15 to 25 min and hydration volume is 95 to 115 ml. Thus, drug loading depends on drug: lecithin ratio which has a positive effect. As lecithin concentration increases the drug loading increases as drug has more lipid bilayer to disperse into. The sonication time has negative effect on drug loading. This may be attributed to the higher energy applied to the system which makes its unstable.

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Exploiting in-situ solid-state NMR spectroscopy to probe the early stages of hydration of calcium aluminate cement

Exploiting in-situ solid-state NMR spectroscopy to probe the early stages of hydration of calcium aluminate cement

The application of solid-state NMR spectroscopy to understand fundamental aspects of cement science has a long history [1–3]. Although cements often have complex compositions, solid-state NMR provides key information about the structures of some of the common components, particularly from solid-state 27 Al and 29 Si NMR measurements. However, while other experimental techniques (including soft X-ray imaging [4] and synchrotron X-ray powder diffraction [5]) have been applied for in-situ studies of hydration processes, previous NMR investigations have been limited to ex-situ studies, involving the examination of samples extracted at different stages during the hydration process and then dehydrated to halt the reaction before measurement of the solid-state NMR data [1,2,6,7]. In part, the focus on ex-situ studies to date has been dictated by technical challenges associated with sealing liquid-containing samples in standard solid-state NMR rotors and then subjecting these samples to magic-angle spinning (MAS) at frequencies of several kHz without leakage of the liquid into the NMR magnet. However, there has been signi fi cant progress in recent years in the development of sealing systems for carrying out MAS on liquid-containing samples, which

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Curing of Concrete by Carbon Dioxide

Curing of Concrete by Carbon Dioxide

The curing carbonation process is different from weathering carbonation that naturally occurs in hardened concrete. Weathering carbonation is well known and has been extensively investigated. In weathering carbonation, hydration takes place first when cement is mixed with water and is followed by natural carbonation, a reaction between the hydration products and the atmospheric carbon dioxide. The weathering reactions of major hydration products (calcium hydroxide and calcium-silicate-hydrates) are: Ca(OH)2+2C02 → CaC03+ H20 ( 1 ) 3CaO+2Si02 +3H20 +3C02+→ 3CaC03 +2Si02+3H20 ( 2 ) Weathering carbonation of concrete is a slow process, and becomes a concern in steel reinforced concrete structure since the carbonation decreases concrete pH, which helps initial corrosion of reinforcing steel. The underlying principal is that the cement compounds C3S and C2S are instantaneously carbonized into calcium carbonate and silica gel once cement is mixed with water and exposed to the carbon dioxide gas. Curing carbonation is an accelerated curing process that injects CO2 gas into the curing vessel at room temperature, diffuses the carbon dioxide into the fresh concrete under low pressure, and transforms the gaseous CO2 into solid calcium carbonates (CaCO3).

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An assessment of the court’s role in the withdrawal of clinically assisted nutrition and hydration from patients in the permanent vegetative state

An assessment of the court’s role in the withdrawal of clinically assisted nutrition and hydration from patients in the permanent vegetative state

As regards the reassurance of families, we have seen that declaratory relief can have three main ‘therapeutic’ benefits: (1) it can have a ceremonial function in moving the family on from the unusual state of limbo, (2) it can affirm the extreme difficulty faced by families in such situations, and (3) it can reassure families about them not being responsible for the death of their relatives. Each of these functions could, it is suggested, be performed by carefully considered and formal best interests meetings between health-care teams and family members. The recent clinical guidelines of the RCP recommends that a formal best interests meeting takes place within 4 weeks of a diagnosis of PVS (ie once it is deemed ‘permanent’, which will be at least 6 months to a year after the original injury, depending on the nature of the injury). This meeting should involve the treating team, the family, and the responsible health authority, and its purpose should be ‘to decide whether continued life-sustaining treatment is in the patient’s best interests’. It also recommends that families should be provided with support that is ‘practical, emotional and psychological’, noting ‘anticipatory bereave- ment work may be required’. 147

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EVOLUTIONARY ROUTE IN THE SOLID STATE FORMATION OF BUILDING COMPOSITES

EVOLUTIONARY ROUTE IN THE SOLID STATE FORMATION OF BUILDING COMPOSITES

Stage of spontaneous pattern formation Evolutionary change a hardening system objectively linked to the third evolutionary transition “agglomeration radio ® spontaneous pattern formation”. In the late stage of growth and agglomeration step system state far from equilibrium, so a certain period within the sys- tem simultaneously develop the redistribution of matter and energy, which leads to spontane- ous ordering system. There is a phenomenon of morphological selection and there is a “change in the geometry of the system”, ordered ag- gregates formed a certain shape and size of the place of less ordered forms. Processes leading to the approximation of the size and shape of the particles to equilibrium, and called mor- phological selection. Streamlining processes

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