Gravitational Force and the Cardiovascular System

Cardiovascular responses to changes in gravitational force are considered. Man is ideally suited to his 1-g environment. Although cardiovascular adjustments are required to accommodate to postural changes and exercise, these are fully accomplished for short periods (min). More challenging stresses are those of short-term microgravity (h) and long-term microgravity (days) and of gravitational forces greater than that of Earth. The latter can be simulated in the laboratory and quantitative studies can be conducted

Wheel-running activity modulates circadian organization and the daily rhythm of eating behavior

Consumption of high-fat diet acutely alters the daily rhythm of eating behavior and circadian organization (the phase relationship between oscillators in central and peripheral tissues) in mice. Voluntary wheel-running activity counteracts the obesogenic effects of high-fat diet and also modulates circadian rhythms in mice. In this study, we sought to determine whether voluntary wheel-running activity could prevent the proximate effects of high-fat diet consumption on circadian organization and behavioral rhythms in mice. Mice were housed with locked or freely rotating running wheels and fed chow or high-fat diet for 1 week and rhythms of locomotor activity, eating behavior, and molecular timekeeping (PERIOD2::LUCIFERASE luminescence rhythms) in ex vivo tissues were measured. Wheel-running activity delayed the phase of the liver rhythm by 4 h in both chow- and high-fat diet-fed mice. The delayed liver phase was specific to wheel-running activity since an enriched environment without the running wheel did not alter the phase of the liver rhythm. In addition, wheel-running activity modulated the effect of high-fat diet consumption on the daily rhythm of eating behavior. While high-fat diet consumption caused eating events to be more evenly dispersed across the 24 h-day in both locked-wheel and wheel-running mice, the effect of high-fat diet was much less pronounced in wheel-running mice. Together these data demonstrate that wheel-running activity is a salient factor that modulates liver phase and eating behavior rhythms in both chow- and high-fat-diet fed mice. Wheel-running activity in mice is both a source of exercise and a self-motivating, rewarding behavior. Understanding the putative reward-related mechanisms whereby wheel-running activity alters circadian rhythms could have implications for human obesity since palatable food and exercise may modulate similar reward circuits

\u3cem\u3emPeriod2\u3csup\u3eBrdm1\u3c/sup\u3e\u3c/em\u3e and Other Single \u3cem\u3ePeriod\u3c/em\u3e Mutant Mice Have Normal Food Anticipatory Activity

Animals anticipate the timing of food availability via the food-entrainable oscillator (FEO). The anatomical location and timekeeping mechanism of the FEO are unknown. Several studies showed the circadian gene, Period 2, is critical for FEO timekeeping. However, other studies concluded that canonical circadian genes are not essential for FEO timekeeping. In this study, we re-examined the effects of the Per2Brdm1 mutation on food entrainment using methods that have revealed robust food anticipatory activity in other mutant lines. We examined food anticipatory activity, which is the output of the FEO, in single Period mutant mice. Single Per1, Per2, and Per3 mutant mice had robust food anticipatory activity during restricted feeding. In addition, we found that two different lines of Per2 mutant mice (ldc and Brdm1) anticipated restricted food availability. To determine if FEO timekeeping persisted in the absence of the food cue, we assessed activity during fasting. Food anticipatory (wheel-running) activity in all Period mutant mice was also robust during food deprivation. Together, our studies demonstrate that the Period genes are not necessary for the expression of food anticipatory activity

Effect of torso morphology on maximum hydrodynamic resistance in front crawl swimming

The aim of this study was to determine the influence of torso morphology on maximum instantaneous hydrodynamic resistance in front crawl swimming. Outlines of the torso in the frontal and anteroposterior planes were calculated from photographic images to determine continuous form gradients (m/m) for the anterior, posterior and lateral aspects of the torso. Torso cross-sectional areas at each vertical sample (0.001 m) were used to calculate maximal rate of change in cross-sectional area (m2/m) in the chest-waist and waist-hip segments. During the non-propulsive hand phase in middle-long distance front crawl, kicking propulsion is negligible and therefore the net force is equal to the drag. Drag coefficients were calculated at the instant of maximum horizontal deceleration of centre of mass during the non-propulsive hand phase of 400 m pace front crawl. Maximal rate of change in cross-sectional area (r = 0.44, p = 0.014) and posterior form gradient (r = 0.50, p = 0.006) of the waist-hip torso segment had moderate positive correlations with the maximal drag coefficient. A regression model including these variables explained 41% of the variance (p = 0.001). Indentation at the waist and curvature of the buttocks may result in greater drag force and influence swimming performance

Health Insurance and Bankruptcy Risk: Examining the Impact of the Affordable Care Act

The passage of the Patient Protection and Affordable Care Act (“ACA”) in 2010 represented a watershed moment for healthcare in the United States. As is well-noted, the federal courts are still wrangling over the constitutionality of the law, and there is significant uncertainty regarding the extent to which the ACA will survive these legal battles. Unquestionably, the ACA has expanded access to health insurance for many millions of Americans. Prior to the advent of the ACA, Medicaid income eligibility for adults without dependents was approximately 61 percent of the Federal Poverty Line. Empirical studies since the advent of the ACA have generally proven positive in exploring the relationship between the expansion of available health insurance upon personal finances. This Essay is one of the first empirical efforts to specifically address the association between the ACA and the rate of bankruptcy filings across the country. The studies just described tended to focus on medical bills, rather than bankruptcy specifically. Similarly, most legal scholars have focused primarily on the causal relationship between the presence of overwhelming medical debt and the need to file for bankruptcy relief. Years of research have proven inconclusive on this front, largely because of the difficulties associated with defining and measuring “medical debt.” Stated differently, our findings suggest that by more robustly providing health insurance coverage for low-income Americans, the ACA has had some effect on the risk of filing for bankruptcy protection. Although future research is still needed to uncover causal mechanisms on the role possessing health insurance may have on an individual’s ultimate decision to file for bankruptcy relief, our preliminary findings suggest that the ACA may lower one’s risk for bankruptcy

Tissue-Specific Function of Period3 in Circadian Rhythmicity

The mammalian circadian system is composed of multiple central and peripheral clocks that are temporally coordinated to synchronize physiology and behavior with environmental cycles. Mammals have three homologs of the circadian Period gene (Per1, 2, 3). While numerous studies have demonstrated that Per1 and Per2 are necessary for molecular timekeeping and light responsiveness in the master circadian clock in the suprachiasmatic nuclei (SCN), the function of Per3 has been elusive. In the current study, we investigated the role of Per3 in circadian timekeeping in central and peripheral oscillators by analyzing PER2::LUCIFERASE expression in tissues explanted from C57BL/6J wild-type and Per3−/− mice. We observed shortening of the periods in some tissues from Per3−/− mice compared to wild-types. Importantly, the periods were not altered in other tissues, including the SCN, in Per3−/− mice. We also found that Per3-dependent shortening of endogenous periods resulted in advanced phases of those tissues, demonstrating that the in vitro phenotype is also present in vivo. Our data demonstrate that Per3 is important for endogenous timekeeping in specific tissues and those tissue-specific changes in endogenous periods result in internal misalignment of circadian clocks in Per3−/− mice. Taken together, our studies demonstrate that Per3 is a key player in the mammalian circadian system

Evaluation of a smartphone food diary application using objectively measured energy expenditure

BACKGROUND: Dietary assessment methods are limited in their ability to adequately measure food and beverage consumption. Smartphone applications may provide a novel method of dietary assessment to capture real-time food intake and the contextual factors surrounding eating occasions. The aim of this study is to evaluate the capability of a Smartphone meal diary app ("FoodNow") to measure food intake using a validated objective method for assessing energy expenditure among young adults. METHODS: Participants (18-30 years) used FoodNow over four non-consecutive days recording all eating occasions through a combination of written text, and/or optional images and voice recordings. A series of contextual questions were also completed. Participants wore the validated SenseWear Armband (BodyMedia Inc, USA) during the same period to measure free-living energy expenditure. Intra-class correlation coefficients (ICC) estimated the reliability of FoodNow to measure estimated energy intake compared to measured energy expenditure. RESULTS: Ninety participants (71 female, 19 male; mean age = 24.9 ± 4.1 years) were recruited to use the FoodNow app to record their eating occasions. Thirteen were excluded as they did not meet minimum requirements for number of reporting days (n = 3) or SenseWear Armband wear time (5 days of 11 h), while 21 participants were excluded after being identified as mis-reporters (Huang method). Among the remaining sample (n = 56), reliability between estimated energy intake and measured energy expenditure was high (ICC, 95% CI: 0.75, 0.61-0.84). CONCLUSIONS: FoodNow is a suitable method for capturing estimated energy intake data from young adults. Despite wide levels of agreement at the individual level (-3709 kJ to 2056 kJ), at the group level, FoodNow appears to have potential as a dietary assessment tool. This new dietary assessment method will offer an alternative and novel method of dietary assessment which is capable of collecting both estimated energy intake and contextual factors surrounding eating occasions. Information collected may be used to inform future public health messages or research interventions

Imagine being off-the-grid: Millennials' Perceptions of Digital-Free Travel

The blurred boundaries between home and away facilitated by the ubiquitous connectivity have resulted in restlessness in private life, even on holiday. Disconnecting from technology on holiday could potentially contribute to travellers’ psychological sustainability. This article aims to theorise the perceptions of millennials towards digital-free travel (DFT). We interviewed 17 millennials and applied the Unified Theory of Acceptance and Use of Technology (UTAUT) qualitatively to uncover deep insights into their perceptions. Millennials in the research believe that DFT is beneficial for their well-being, but also have concerns regarding social expectations, technology dependence and environmental support. This article firstly contributes towards the psychological sustainability from the perspective of digital well-being in tourism. Second, the qualitative use of UTAUT in a technology disconnection setting is novel. Finally, the study contributes to the empirical understanding of DFT from the aspect of millennials’ perceptions. The study proposes that mental “away” should be aligned with physical “away” by reducing technology use to achieve psychological sustainability on holiday