Matching Items (8)

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The Role of Fruits and Vegetables in Hydration of 3-13 y Old Children

Description

Background: Inadequate hydration can have several adverse effects on health. In children, it can negatively affect their health and cognitive performance. The effects of fruits and vegetables on the hydration

Background: Inadequate hydration can have several adverse effects on health. In children, it can negatively affect their health and cognitive performance. The effects of fruits and vegetables on the hydration of children have not been adequately studied. This study included 177 children in this age group and examined the contribution of fruits and vegetables (F&V) on total water intake (TWI).

Methods: Two-day dietary and fluid intake records as well as 24-h urine samples were collected from 177 children over different weekends. The dietary records were analyzed with Nutrition Data System for Research to obtain TWI from food (TWI-F) as well as TWI from fruits and vegetables (TWI-FV). The fluid intake data was used to determine TWI from liquids (TWI-L). The urine samples were analyzed for volume (UVol), urine osmolality (UOsm), urine specific gravity (USG), and urine color (UCol) to examine hydration. Age was categorized into 3, 4-8, and 9-13 y based on the Institute of Medicine (IOM).

Results: About 52% of the children did not meet water intake recommendations by IOM and 39.8% of the children were underhydrated based on elevated urine osmolality. The average TWI was found to be 1,911± 70 mL. TWI-F was observed to be 492±257 mL, while TWI-L was 1,419±702 mL. TWI-FV only contributed 200±144 mL. As expected TWI was significantly higher in the older children (9-13 y) than children in other age group (3 and 4-8 y). The average UVol was 709±445 mL, USG was 1.019±0.006, UOsm was 701±233 mOsm·kg-1, and UCol was a 3±1 (based on the urine color chart). Only urine volume seemed to be influenced by the age of the children as it was significantly higher for the children in the 9-13 y age group.

Conclusion: Nearly half of the children did not meet water recommendations by IOM and were underhydrated. Fruits and vegetables did not have a significant contribution to TWI. Dietary interventions to increase F&V consumption, lower consumption of SSB, as well as maintain proper hydration may benefit the health of children.

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Created

Date Created
  • 2020-05

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Dietary Intake Behaviors of Recreational Mountain Hikers Climbing "A" Mountain in Summer and Fall

Description

More than 200 hikers are rescued annually in the greater Phoenix area. This study

examined the impact of hiking in hot (HOT), dry temperatures versus moderate (MOD)

temperatures on dietary intake behaviors

More than 200 hikers are rescued annually in the greater Phoenix area. This study

examined the impact of hiking in hot (HOT), dry temperatures versus moderate (MOD)

temperatures on dietary intake behaviors as well as markers of heat stress. Twelve

recreational mountain hikers climbed “A” Mountain four consecutive times (4-miles) on

a HOT day (WBGT=31.6 °C) and again on a MOD day (WBGT= 19.0 °C). Simulated

food and fluid behavior allowed participants to bring what they normally would for a 4-

mile hike and to consume both ad libitum. The following heat stress indicators (mean

difference; p-value), were all significantly higher on the HOT hike compared to the MOD

hike: average core temperature (0.6 °C; p=0.002), average rating of perceived exertion

(2.6; p=0.005), sweat rate (0.54; p=0.01), and fluid consumption (753; p<0.001). On the

HOT hike, 42% of the participants brought enough fluids to meet their individual

calculated fluid needs, however less than 20% actually consumed enough to meet those

needs. On the MOD hike, 56% of participants brought enough fluids to meet their needs,

but only 33% actually consumed enough to meet them. Morning-after USG samples

≥1.020 indicating dehydration on an individual level showed 75% of hikers after the

HOT hike and 67% after the MOD hike were unable to compensate for fluids lost during

the previous day’s hike. Furthermore, participant food intake was low with only three

hikers consuming food on the hot hike, an average of 33.2g of food. No food was

consumed on the MOD hike. These results demonstrate that hikers did not consume

enough fluids to meet their needs while hiking, especially in the heat. They also show

heat stress negatively affected hiker’s physiological and performance measures. Future

recommendations should address food and fluid consumption while hiking in the heat.

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Agent

Created

Date Created
  • 2020

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The use of technology compared to the traditional educational methods to improve hydration status of club-level collegiate athletes with a focus on cognitive performance

Description

It is widely documented and accepted that athletes have difficulty maintaining adequate hydration status and that dehydration is a key risk factor for the heat-related illnesses commonly observed among athletes.

It is widely documented and accepted that athletes have difficulty maintaining adequate hydration status and that dehydration is a key risk factor for the heat-related illnesses commonly observed among athletes. Research has also suggested that hydration status can influence cognitive performance. Educational interventions focused on rehydration strategies have had minimal success reducing dehydration rates; hence, alternative interventions promoting adequate hydration status in athletes should be explored. This trial examined the efficacy of a commercial hydration mobile application (app) for reducing dehydration rates in campus athletes. Fifty-eight college students aged 18-40 y, who participated in club-level collegiate athletics were recruited from a large Southwestern university and randomized by team to one of two study arms, the Standard of Care – Education (EDU) or the hydration mobile app (APP), to determine if app technology improved hydration status as compared to traditional education messaging. Twenty-three (79%) in the EDU group and twenty (69%) in the APP group were mildly-dehydrated at baseline based on the three-day averages of hydration assessment (USG 1.010). Moreover, 31% (n=9) and 28% (n=8) of the EDU and APP groups, respectively, were dehydrated (USG 1.020). No significant differences were found between the EDU and APP groups following the intervention. Three-day average post-intervention USG testing showed 76% (n=22) and 72% (n=21) of the EDU and APP groups respectively were at best mildly-dehydrated. Additionally, 28% (n=8) and 17% (n=5) were considered dehydrated. Neither intervention improved hydration status after four weeks of treatment. Further analyses of cognitive measures were conducted by hydration assessment groups at baseline and post-intervention: hydrated (HYD) (USG < 1.020) or dehydrated (DEH) (USG 1.020). No significant differences between hydration status were found between intervention groups. Additionally, no significant improvements were seen for either group, which indicates there is still a need for a novel way to improve hydration status in this population. Multi-dimensional interventions and individualized interventions to improve hydration status in this at-risk population may be more effective. Additional research should be conducted to determine if there is any cognitive performance enhancement associated with dehydration or mild-dehydration by reassessing previous data and conducting future trials.

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Created

Date Created
  • 2017

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Early age characterization and microstructural features of sustainable binder systems for concrete

Description

Concrete is the most widely used infrastructure material worldwide. Production of portland cement, the main binding component in concrete, has been shown to require significant energy and account for approximately

Concrete is the most widely used infrastructure material worldwide. Production of portland cement, the main binding component in concrete, has been shown to require significant energy and account for approximately 5-7% of global carbon dioxide production. The expected continued increased use of concrete over the coming decades indicates this is an ideal time to implement sustainable binder technologies. The current work aims to explore enhanced sustainability concretes, primarily in the context of limestone and flow. Aspects such as hydration kinetics, hydration product formation and pore structure add to the understanding of the strength development and potential durability characteristics of these binder systems. Two main strategies for enhancing this sustainability are explored in this work: (i) the use of high volume limestone in combination with other alternative cementitious materials to decrease the portland cement quantity in concrete and (ii) the use of geopolymers as the binder phase in concrete. The first phase of the work investigates the use of fine limestone as cement replacement from the perspective of hydration, strength development, and pore structure. The nature of the potential synergistic benefit of limestone and alumina will be explored. The second phase will focus on the rheological characterization of these materials in the fresh state, as well as a more general investigation of the rheological characterization of suspensions. The results of this work indicate several key ideas. (i) There is a potential synergistic benefit for strength, hydration, and pore structure by using alumina and in portland limestone cements, (ii) the limestone in these systems is shown to react to some extent, and fine limestone is shown to accelerate hydration, (iii) rheological characteristics of cementitious suspensions are complex, and strongly dependent on several key parameters including: the solid loading, interparticle forces, surface area of the particles present, particle size distribution of the particles, and rheological nature of the media in which the particles are suspended, and (iv) stress plateau method is proposed for the determination of rheological properties of concentrated suspensions, as it more accurately predicts apparent yield stress and is shown to correlate well with other viscoelastic properties of the suspensions.

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Agent

Created

Date Created
  • 2014

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Clarifying the dehydration cascade: the relationship between water, stress, and immune function in squamates

Description

There is considerable recent interest in the dynamic nature of immune function in the context of an animal’s internal and external environment. An important focus within this field of ecoimmunology

There is considerable recent interest in the dynamic nature of immune function in the context of an animal’s internal and external environment. An important focus within this field of ecoimmunology is on how availability of resources such as energy can alter immune function. Water is an additional resource that drives animal development, physiology, and behavior, yet the influence hydration has on immunity has received limited attention. In particular, hydration state may have the greatest potential to drive fluctuations in immunity and other physiological functions in species that live in water-limited environments where they may experience periods of dehydration. To shed light on the sensitivity of immune function to hydration state, I first tested the effect of hydration states (hydrated, dehydrated, and rehydrated) and digestive states on innate immunity in the Gila monster, a desert-dwelling lizard. Though dehydration is often thought to be stressful and, if experienced chronically, likely to decrease immune function, dehydration elicited an increase in immune response in this species, while digestive state had no effect. Next, I tested whether dehydration was indeed stressful, and tested a broader range of immune measures. My findings validated the enhanced innate immunity across additional measures and revealed that Gila monsters lacked a significant stress hormone response during dehydration (though results were suggestive). I next sought to test if life history (in terms of environmental stability) drives these differences in dehydration responses using a comparative approach. I compared four confamilial pairs of squamate species that varied in habitat type within each pair—four species that are adapted to xeric environments and four that are adapted to more mesic environments. No effect of life history was detected between groups, but hydration was a driver of some measures of innate immunity and of stress hormone concentrations in multiple species. Additionally, species that exhibited a stress response to dehydration did not have decreased innate immunity, suggesting these physiological responses may often be decoupled. My dissertation work provides new insight into the relationship between hydration, stress, and immunity, and it may inform future work exploring disease transmission or organismal responses to climate change.

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Created

Date Created
  • 2016

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Sun Radiation in Moderate Environmental Conditions Does Not Affect Fluid Balance in Female Collegiate Soccer Players

Description

Exposure to sun radiation (SUR) with ambient temperature may be an influencer on athletes’ sweat loss in different environments, but the results are not currently known. The purpose of this

Exposure to sun radiation (SUR) with ambient temperature may be an influencer on athletes’ sweat loss in different environments, but the results are not currently known. The purpose of this study was to determine the effects of SUR on fluid balance (FB) and hydration status (HS) in athletes exercising indoors and outdoors.

Initial FB and HS were assessed in NCAA-DI female soccer athletes (n=10) of a single team in temperate, dry conditions (55-68°F, 18-48% humidity) who were monitored during 3 practices of equal estimated energy expenditure (EE): two outdoors in direct SUR (cold/moderate temperatures) and one indoors without SUR (moderate temperatures). Humidity, temperature, and wet bulb globe temperature (WBGT – a measurement partly based on SUR, including ambient temperature/relative humidity) were recorded using Heat Stress Meters placed in the direct sun or in the shade. Each athlete’s semi-nude dry body weight was recorded before and after exercise. Urine samples were taken before, after, and the morning after. Urine specific gravity (USG) was tested to assess HS. Athletes wore combined heart rate and activity monitors to estimate EE and were provided ad libitum water and/or a zero-calorie sports drink. Their total intake included weights of consumed food and drink. Sweat rate was calculated using body weight change and intakes of liquids minus urine losses/hour.

Two-way repeated measures ANOVA analyzed group-level differences. No significance was found in total FB (1.01±0.32 L/hr) or EE/hr (444±97.1 kcal/hr) across all days (p>0.05). In analyzing individual athlete results, 40% had consistent USG >1.025 (p=0.001) suggesting potential dehydration. These 4 athletes selected water as their beverage, of which is known that consuming only water does not stimulate drinking behavior as does electrolyte drinks. The remaining 60% were overall not dehydrated (USG <1.025) but must be aware of incidental dehydration in hotter temperatures.

The conclusion is that in low-moderate temperatures, athletes self-regulate drinking habits and achieve fluid balance during exercise with or without sun radiation. However, athletes with average USG >1.025 are likely to remain dehydrated in moderate temperatures. The findings suggest that more education would benefit these athletes by ensuring hydration in any environment.

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Agent

Created

Date Created
  • 2019

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Electrostatic properties of water at interfaces with nanoscale solutes

Description

Molecular dynamics simulations were used to study properties of water at the interface with nanometer-size solutes. We simulated nonpolar attractive Kihara cavities given by a Lennard-Jones potential shifted by a

Molecular dynamics simulations were used to study properties of water at the interface with nanometer-size solutes. We simulated nonpolar attractive Kihara cavities given by a Lennard-Jones potential shifted by a core radius. The dipolar response of the hydration layer to a uniform electric field substantially exceeds that of the bulk. For strongly attractive solutes, the collective dynamics of the hydration layer become slow compared to bulk water, as the solute size is increased. The statistics of electric field fluctuations at the solute center are Gaussian and tend toward the dielectric continuum limit with increasing solute size. A dipolar probe placed at the center of the solute is sensitive neither to the polarity excess nor to the slowed dynamics of the hydration layer. A point dipole was introduced close to the solute-water interface to further study the statistics of electric field fluctuations generated by the water. For small dipole magnitudes, the free energy surface is single-welled, with approximately Gaussian statistics. When the dipole is increased, the free energy surface becomes double-welled, before landing in an excited state, characterized again by a single-welled surface. The intermediate region is fairly broad and is characterized by electrostatic fluctuations significantly in excess of the prediction of linear response. We simulated a solute having the geometry of C180 fullerene, with dipoles introduced on each carbon. For small dipole moments, the solvent response follows the results seen for a single dipole; but for larger dipole magnitudes, the fluctuations of the solute-solvent energy pass through a second maximum. The juxtaposition of the two transitions leads to an approximately cubic scaling of the chemical potential with the dipole strengh. Umbrella sampling techniques were used to generate free energy surfaces of the electric potential fluctuations at the heme iron in Cytochrome B562. The results were unfortunately inconclusive, as the ionic background was not effectively represented in the finite-size system.

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Agent

Created

Date Created
  • 2012

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Water proximity and its effect on consumption: in a corporate setting

Description

Water makes up about 45-70% of a human body's total weight. It is estimated that 80% of the human brain's tissue is composed of water. Cognitive productivity is altered when

Water makes up about 45-70% of a human body's total weight. It is estimated that 80% of the human brain's tissue is composed of water. Cognitive productivity is altered when the body is in a mere 2% dehydrated state. Several cognitive functions impacted by dehydration include: visual motor tracing, short-term recall, attentiveness, and mathematic efficiency. It is estimated that 80% of the U.S. adult population endures the majority of their day in a mildly dehydrated state.

Participants were employees working full-time jobs with Arizona State University or Tri Star Motor Company. Employees had to be 18 or older were invited to join the study. Employees participating in the study lived within the the greater Phoenix area. Participants of all races, genders, activity statuses, and BMIs were encouraged to join.

A one-arm, pre-test, post-test study design was utilized. We examined whether the hydration status of participants in the intervention improved or worsened during the course of the intervention, and then attributed any such improvement or deterioration to the intervention. Urine collections from an afternoon sample were gathered before and after the one-week intervention. For the intervention, the participating offices received a water dispensing system in close proximity to employee desk spaces. A reusable water bottle was also given to each participant. Urine specific gravity (USG) was assessed in all urine samples to indicate hydration status, and all participants completed water intake surveys before and after the intervention.

From this study, the overall change in water intake over the course of the one-week intervention was 143 ounces/day. This is an average of adding two and a half 8 oz glasses of water each day of the week per participant. USG also decreased significantly at the end of the intervention in comparison to the baseline value. In the greater body of research, this study strengthens the viability of inputting a hydration station and offering reusable water bottles to employees. This cost-effective method is an easy way to incorporate employee wellness in the workplace. The benefit of employees to drink more water is numerous, including increased focus, mental reactivity, and overall mood and wellness.

Contributors

Agent

Created

Date Created
  • 2018