What do Australian health consumers believe about commercial advertisements and testimonials? a survey on health service advertising.

BACKGROUND: There has been little examination of consumer attitudes towards the commercial advertising of healthcare services in Australia and how marketing is used by consumers in their health decision-making. In this research, we examined how consumers reported commercial advertising helped them to understand the health services available to them and the influence that marketing had upon their choices. METHODS: A survey instrument using a Likert scale to indicate agreement or disagreement with 21 questions was developed using qualitative interviews before being distributed online within Australia. Sampling of participants was stratified by age, gender and location. The results were subjected to statistical analysis with Spearman Rank Correlation test being used for bivariate analysis. RESULTS: One thousand five hundred sixty-four complete surveys were collected. The results revealed certain consumer beliefs, for example; the title of 'Dr' was believed to indicate skill and high levels of training (81.0%), with 80.3% agreeing incorrectly that use of the title was strictly regulated. Participants reported to have a higher confidence in their own abilities (71.2%) than the public (52.8%) in assessing health advertising. The level of self-confidence increased with higher education level and decreased by age (p < 0.05). Testimonials were reported to be lacking in reliability (67.7%) and that they should not be used in healthcare in the same manner as they are used in other industries. Only 44.8% of participants reported that they felt confident to spot a review that was not written by a genuine user of a service. CONCLUSIONS: The data demonstrated that many health consumers felt that while commercial health advertising was helpful, it was also confusing, with many participants also holding mistaken beliefs around other elements of commercial health advertising. While the advertising of healthcare services might have educational effects and be superficially empowering, advertising is primarily intended to sell, not educate. This research demonstrates that there is significant potential for healthcare advertising to mislead. Future developments in regulatory health advertising policy, and the related ethical frameworks developed by professional healthcare associations, need to consider how the consumers of healthcare services might be better protected from misleading and predatory advertising practices.

The influence of sleep health on dietary intake: a systematic review and meta-analysis of intervention studies.

BACKGROUND: Poor dietary intake increases disease risk, and poor sleep influences diet. This systematic review and meta-analysis of intervention studies aimed to evaluate the effect of sleep health on dietary intake in adults. METHODS: Five online databases were used to identify studies published between 1970 and 2019. Included studies were interventions that modified sleep and reported dietary outcomes. RESULTS: Fifty four full texts were assessed and 24 publications were included. Following risk of bias appraisal, data were narratively summarised and a sub-group of studies (n = 15) was meta-analysed to determine the effect of sleep on dietary intake. One intervention modified sleep timing and 23 modified duration. Sleep duration was partially restricted (≤5.5 h night-1 ) (n = 16), totally restricted (n = 4), partially and totally restricted (n = 1), and extended (n = 2). Dietary outcomes were energy intake (n = 24), carbohydrate, fat, protein intake (n = 20), single nutrient intake (n = 5), diet quality (n = 1) and food types (n = 1). Meta-analysis indicated partial sleep restriction results in higher energy intake in intervention compared with control [standardised mean difference (SMD) = 0.37; 95% confidence interval (CI) = 0.21-0.52; P < 0.001], with a mean difference of 204 kcal (95% CI = 112-295; P < 0.001) in daily energy intake, and a higher percentage of energy from fat, protein, carbohydrate (fat: SMD = 0.33; 95% CI = 0.16-0.51; P < 0.001; protein: SMD = 0.30, 95% CI = 0.12-0.47, P = 0.001; carbohydrate: SMD = 0.22, 95% CI = 0.04-0.39, P = 0.014). CONCLUSIONS: Partial sleep restriction with duration of ≤5.5 h day-1 increases daily energy intake, as well as fat, protein and carbohydrate intake. Further research is needed to determine the relationship between other dimensions of sleep health and dietary intake.

Controlling the Structure of MoS2 Membranes via Covalent Functionalization with Molecular Spacers.

Restacked two-dimensional (2D) materials represent a new class of membranes for water-ion separations. Understanding the interplay between the 2D membrane's structure and the constituent material's surface chemistry to its ion sieving properties is crucial for further membrane development. Here, we reveal, and tune via covalent functionalization, the structure of MoS2-based membranes. We find features on both the ∼1 nm (interlayer spacing) and ∼100 nm (mesoporous voids between layers) length scales that evolve with the hydration level. The functional groups act as permanent molecular spacers, preventing local impermeability caused by irreversible restacking and promoting the uniform rehydration of the membrane. Molecular dynamics simulations show that the choice of functional group tunes the structure of water within the MoS2 channel and consequently determines the hydrated interlayer spacing. We demonstrate that MoS2 membranes functionalized with acetic acid have consistently ∼92% rejection of Na2SO4 with a flux of ∼1.5 lm-2 hr-1 bar-1.

IR Spectroscopy Can Reveal the Mechanism of K+ Transport in Ion Channels.

Ion channels like KcsA enable ions to move across cell membranes at near diffusion-limited rates and with very high selectivity. Various mechanisms have been proposed to explain this phenomenon. Broadly, there is disagreement among the proposed mechanisms about whether ions occupy adjacent sites in the channel during the transport process. Here, using a mixed quantum-classical approach to calculate theoretical infrared spectra, we propose a set of infrared spectroscopy experiments that can discriminate between mechanisms with and without adjacent ions. These experiments differ from previous ones in that they independently probe specific ion binding sites within the selectivity filter. When ions occupy adjacent sites in the selectivity filter, the predicted spectra are significantly redshifted relative to when ions do not occupy adjacent sites. Comparisons between theoretical and experimental peak frequencies will therefore discriminate the mechanisms.

Cross-Sectional Associations Between Dietary Antioxidant Vitamins C, E and Carotenoid Intakes and Sarcopenic Indices in Women Aged 18-79 Years.

The prevalence of sarcopenia is increasing in aging populations, so prevention is critical. Vitamins (A, C, E and carotenoids) modify skeletal muscle via protein and collagen synthesis and anti-inflammatory activities. Previous studies have not investigated intake of these vitamins in relation to sarcopenic indices in both younger and older-aged women. Indices of skeletal muscle mass (as fat-free mass (FFM) relative to body size) were measured using DXA and leg explosive power (LEP) using the Nottingham Power Rig in 2570 women aged 18-79 years. Adjusted measures of skeletal muscle were calculated according to quintiles of vitamin C, E, retinol and carotenoid intake, derived from Food Frequency Questionnaires, after stratification by age. Higher vitamin C intake was associated with significantly higher indices of FFM and LEP, (Q5-Q1 = 2.0-12.8%, P < 0.01-0.02). Intakes of total and individual carotenoids were significantly associated with indices of FFM and LEP (Q5-Q1 = 1.0-7.5%). Vitamin E was significantly associated with FFM% and FFMBMI only. In mutually adjusted analysis with vitamin C, total carotene, vitamin E and protein in the model, the strongest associations were with vitamin C. These associations were stronger in younger women (< 65 years). For the first time, our research shows higher dietary intakes of antioxidant vitamins, particularly vitamin C, is associated with higher skeletal muscle mass and power in free-living women. These findings have relevance for the treatment and prevention of frailty and sarcopenia throughout adulthood.

Unusually strong hydrogen bond cooperativity in particular (H2O)20 clusters.

Drawing upon an intuitive charge-transfer-based picture of hydrogen bonding, we demonstrate that cooperativity effects acting in concert can lead to unusually strong hydrogen bonds in neutral water clusters. The structure, vibrational, and NMR properties of a (H2O)20 pentagonal dodecahedron cluster containing such a strong hydrogen bond were studied using second-order perturbation theory and density functional theory. The hydrogen bond length was found to be shorter than 2.50 Å. A large redshift of over 2000 cm-1 with respect to the isolated water molecule was predicted for the OH stretching frequency of the donor water molecule. A large downfield shift to 13.5 ppm of the isotropic part of the 1H magnetic shielding tensor together with an unusually large shielding anisotropy of 49.9 ppm was obtained. The hydrogen bond energy was calculated using symmetry-adapted perturbation theory and was found to be more than three times stronger than a typical hydrogen bond in liquid water.

Mid-IR spectroscopy of supercritical water: From dilute gas to dense fluid.

Mixed quantum-classical methods are commonly used to calculate infrared spectra for condensed-phase systems. These methods have been applied to study water in a range of conditions from liquid to solid to supercooled. Here, we show that these methods also predict infrared line shapes in excellent agreement with experiments in supercritical water. Specifically, we study the OD stretching mode of dilute HOD in H2O. We find no qualitative change in the spectrum upon passing through the near-critical region (Widom line) or the hydrogen-bond percolation line. At very low densities, the spectrum does change qualitatively, becoming rovibrational in character. We describe this rovibrational spectrum from the perspective of classical mechanics and provide a classical interpretation of the rovibrational line shape for both HOD and H2O. This treatment is perhaps more accessible than the conventional quantum-mechanical treatment.

Fermi resonance in OH-stretch vibrational spectroscopy of liquid water and the water hexamer.

Vibrational spectroscopy of water contains a wealth of information about the structure and dynamics of this fascinating substance. Theoretical modeling of fundamental vibrational transitions in condensed water has proven difficult, and in many circumstances, one cannot reach even qualitative agreement with experiment. Due to the ability of water to form hydrogen bonds of various strengths, the OH stretching band spans several hundreds of wave numbers in the spectra, overlapping with the first overtone of the HOH bending band and triggering a resonance between these two vibrations. This effect, known as Fermi resonance, has been traditionally ignored in theoretical condensed-phase simulations due to the additional computational burden and its deemed low importance. Depending on a particular molecular environment, the Fermi resonance manifests itself from small spectral features in the spectra of liquid water to pronounced distinct peaks in the spectra of ice and water clusters. The goal of this work is to illustrate the effects of including the Fermi resonance coupling between the bending overtone and stretching fundamental vibrations in the mixed quantum-classical formalism developed by Skinner and co-workers on the IR and Raman spectra of liquid water and the water hexamer. We show that by adding the Fermi resonance coupling, we are able to reproduce the location of the peak and a shoulder on the red side of the IR spectrum as well as the bimodal structure of the polarized Raman spectrum of liquid water at 300 K. Very good agreement between theory and experiment is achieved for the IR spectra of the water hexamer as well. We suggest that the Fermi resonance should not be ignored if intricate features of spectra are of interest. In spite of these promising results obtained in the region of a spectrum where Fermi resonance is important, further development of spectroscopic maps is needed to improve agreement with the experiment outside of the frequency range affected by the Fermi resonance.

Perspective: Crossing the Widom line in no man's land: Experiments, simulations, and the location of the liquid-liquid critical point in supercooled water.

The origin of liquid water's anomalous behavior continues to be a subject of interest and debate. One possible explanation is the liquid-liquid critical point hypothesis, which proposes that supercooled water separates into two distinct liquids at low temperatures and high pressures. According to this hypothesis, liquid water's anomalies can be traced back to the critical point associated with this phase separation. If such a critical point actually exists, it is located in a region of the phase diagram known as No Man's Land (NML), where it is difficult to characterize the liquid using conventional experimental techniques due to rapid crystallization. Recently, however, experimentalists have managed to explore NML near the proposed location of the Widom line (i.e., the Kanno-Angell line), thereby providing valuable information concerning the liquid-liquid critical point hypothesis. In this perspective, we analyze these experimental results, in conjunction with molecular dynamics simulations based on the E3B3 water model and discuss their implications for the validity of the liquid-liquid critical point hypothesis and the possible location of water's second critical point.

Communication: Diffusion constant in supercooled water as the Widom line is crossed in no man's land.

According to the liquid-liquid critical point (LLCP) hypothesis, there are two distinct phases of supercooled liquid water, namely, high-density liquid and low-density liquid, separated by a coexistence line that terminates in an LLCP. If the LLCP is real, it is located within No Man's Land (NML), the region of the metastable phase diagram that is difficult to access using conventional experimental techniques due to rapid homogeneous nucleation to the crystal. However, a recent ingenious experiment has enabled measurement of the diffusion constant deep inside NML. In the current communication, these recent measurements are compared, with good agreement, to the diffusion constant of E3B3 water, a classical water model that explicitly includes three-body interactions. The behavior of the diffusion constant as the system crosses the Widom line (the extension of the liquid-liquid coexistence line into the one-phase region) is analyzed to derive information about the presence and location of the LLCP. Calculations over a wide range of temperatures and pressures show that the new experimental measurements are consistent with an LLCP having a critical pressure of over 0.6 kbar.

Percolation in supercritical water: Do the Widom and percolation lines coincide?

Hydrogen bonding distinguishes water from simpler fluids. Here, we use classical molecular dynamics to study the percolation transition in the hydrogen bond network of supercritical water. We find that, contrary to some previous work, the percolation line in both the pressure-temperature and density-temperature planes does not coincide with the Widom line. This difference stems from a fundamental distinction between the Widom line, which is thermodynamic in nature, and the percolation transition, which depends only on connectivity. For example, we show that percolation-related quantities collapse onto master curves when plotted with respect to a measure of connectivity rather than thermodynamic variables. We then use the Galam-Mauger formula to understand the properties of the hydrogen bonding network. We find that the percolation transition in supercritical water can shed light on the hydrogen bonding network in room temperature liquid water.

Food addiction and associations with mental health symptoms: a systematic review with meta-analysis.

BACKGROUND: The present study systematically reviewed the literature aiming to determine the relationships between food addiction, as measured by the Yale Food Addiction Scale (YFAS), and mental health symptoms. METHODS: Nine databases were searched using keywords. Studies were included if they reported: (i) YFAS diagnosis or symptom score and (ii) a mental health outcome, as well as the association between (i) and (ii). In total, 51 studies were included. RESULTS: Through meta-analysis, the mean prevalence of food addiction diagnosis was 16.2%, with an average of 3.3 (range 2.85-3.92) food addiction symptoms being reported. Subanalyses revealed that the mean number of food addiction symptoms in populations seeking treatment for weight loss was 3.01 (range 2.65-3.37) and this was higher in groups with disordered eating (mean 5.2 3.6-6.7). Significant positive correlations were found between food addiction and binge eating [mean r = 0.602 (0.557-0.643), P < 0.05], depression, anxiety and food addiction [mean r = 0.459 (0.358-0.550), r = 0.483 (0.228-0.676), P < 0.05, respectively]. CONCLUSIONS: A significant, positive relationship exists between food addiction and mental health symptoms, although the results of the present study highlight the complexity of this relationship.

Measurements of skeletal muscle mass and power are positively related to a Mediterranean dietary pattern in women.

The age-related loss of skeletal muscle and function are risk factors for osteoporosis and fractures. We found that higher adherence to the Mediterranean diet score was significantly associated with greater fat-free mass and leg explosive power suggesting a role for the Mediterranean Diet in prevention of loss of muscle outcomes. INTRODUCTION: The loss of skeletal muscle mass, strength, and function with age are contributing risk factors for the onset of sarcopenia, frailty, osteoporosis, fractures, and mortality. Nutrition may affect the progression and trajectory of these changes in skeletal muscle but the role of the micronutrient-rich Mediterranean diet (MD) has hardly been investigated in relation to these muscle outcomes. METHODS: We examined associations between the MD score (MDS) and FFM% (fat-free mass / weight × 100), FFMI (fat-free mass/height2), hand grip strength, and leg explosive power (LEP, watts/kg) in a cross-sectional study in 2570 women aged 18-79 years from the TwinsUK study. Measurements of body composition were made using dual-energy X-ray absorptiometry and dietary intake assessed by a food frequency questionnaire. FFM%, FFMI, grip strength, and LEP were compared across quartiles of the MDS after adjustment for covariates, with CRP measured in a subgroup (n = 1658). RESULTS: Higher adherence to the MDS was positively associated with measurements of muscle outcomes, with significant differences of 1.7 % for FFM% and 9.6 % for LEP (P trend <0.001), comparing extreme quartiles of intake, but not with grip strength or CRP concentrations. CONCLUSIONS: For the first time in a northern European population, we have observed significant positive associations between the MDS and FFM% and LEP in healthy women that are potentially clinically relevant, independent of the factors known to influence muscle outcomes. Our findings emphasize the potential role for overall diet quality based on the MD in the prevention of age-related loss of skeletal muscle outcomes.

Two-dimensional infrared spectroscopy of neat ice Ih.

The assignment of the distinct peaks observed in the OH stretch lineshape of ice Ih is controversial. Recent two-dimensional infrared spectroscopic measurements provided new data. The spectra are, however, challenging to interpret and here we provide simulations that help overcome experimental issues as thermal signals and finite pulse duration. We find good agreement with experiment and the difference between H2O and D2O ices is well accounted for. The overall dynamics is demonstrated to be faster than observed for the corresponding liquid water. We find that excitonic cross peaks exist between the dominant exciton peaks. This leads us to conclude that the cross peaks arise due to the formation of delocalized exciton states, which have essentially no directional correlation between their transition dipoles as opposed to what is commonly seen, for example, in isolated water, where the transition dipoles of the eigenstates are perpendicular to each other.

Communication: Vibrational sum-frequency spectrum of the air-water interface, revisited.

Before 2015, heterodyne-detected sum-frequency-generation experiments on the air-water interface showed the presence of a positive feature at low frequency in the imaginary part of the susceptibility. However, three very recent experiments indicate that this positive feature is in fact absent. Armed with a better understanding, developed by others, of how to calculate sum-frequency spectra, we recalculate the spectrum and find good agreement with these new experiments. In addition, we provide a revised interpretation of the spectrum.

Sub- and super-Maxwellian evaporation of simple gases from liquid water.

Non-Maxwellian evaporation of light atoms and molecules (particles) such as He and H2 from liquids has been observed experimentally. In this work, we use simulations to study systematically the evaporation of Lennard-Jones particles from liquid water. We find instances of sub- and super-Maxwellian evaporation, depending on the mass of the particle and the particle-water interaction strength. The observed trends are in qualitative agreement with experiment. We interpret these trends in terms of the potential of mean force and the effectiveness and frequency of collisions during the evaporation process. The angular distribution of evaporating particles is also analyzed, and it is shown that trends in the energy from velocity components tangential and normal to the liquid surface must be understood separately in order to interpret properly the angular distributions.

Evidence for a liquid-liquid critical point in supercooled water within the E3B3 model and a possible interpretation of the kink in the homogeneous nucleation line.

Supercooled water exhibits many thermodynamic anomalies, and several scenarios have been proposed to interpret them, among which the liquid-liquid critical point (LLCP) hypothesis is the most commonly discussed. We investigated Widom lines and the LLCP of deeply supercooled water, by using molecular dynamics simulation with a newly reparameterized water model that explicitly includes three-body interactions. Seven isobars are studied from ambient pressure to 2.5 kbar, and Widom lines are identified by calculating maxima in the coefficient of thermal expansion and the isothermal compressibility (both with respect to temperature). From these data we estimate that the LLCP of the new water model is at 180 K and 2.1 kbar. The oxygen radial distribution function is calculated along the 2 kbar isobar. It shows a steep change in the height of its second peak between 180 and 185 K, which indicates a transition between the high-density liquid and low-density liquid phases and which is consistent with the ascribed location of the critical point. The good agreement of the height of the second peak of the radial distribution function between simulation and experiment at 1 bar, as a function of temperature, supports the validity of the model. The location of the LLCP within the model is close to the kink in the experimental homogeneous nucleation line. We use existing experimental data to argue that the experimental LLCP is at 168 K and 1.95 kbar and speculate how this LLCP and its Widom line might be responsible for the kink in the homogeneous nucleation line.

Low-frequency dynamics of aqueous alkali chloride solutions as probed by terahertz spectroscopy.

Terahertz (far infrared) spectroscopy provides a useful tool for probing both ionic motions in solution and the effect of ionic solutes on the dynamics of the solvent. In this study, we calculate terahertz spectra of aqueous alkali chloride solutions using classical but novel (the water model includes three-body interactions, the ion parameterization is non-standard, and the dipole surface is polarizable) molecular dynamics simulations. The calculated spectra compare reasonably well to experimental spectra. Decomposition of the calculated spectra is used to gain a deeper understanding of the physical phenomena underlying the spectra and the connection to, for instance, the vibrational density of states for the ions. The decomposed results are also used to explain many of the cation-dependent trends observed in the experimental spectra.

IR spectra of water droplets in no man's land and the location of the liquid-liquid critical point.

No man's land is the region in the metastable phase diagram of water where it is very difficult to do experiments on liquid water because of homogeneous nucleation to the crystal. There are a number of estimates of the location in no man's land of the liquid-liquid critical point, if it exists. We suggest that published IR absorption experiments on water droplets in no man's land can provide information about the correct location. To this end, we calculate theoretical IR spectra for liquid water over a wide range of temperatures and pressures, using our E3B3 model, and use the results to argue that the temperature dependence of the experimental spectra is inconsistent with several of the estimated critical point locations, but consistent with others.