Unveiling Carbon Dioxide and Ethanol Diffusion in Carbonated Water-Ethanol Mixtures by Molecular Dynamics Simulations

The diffusion of carbon dioxide (CO2) and ethanol (EtOH) is a fundamental transport process behind the formation and growth of CO2 bubbles in sparkling beverages and the release of organoleptic compounds at the liquid free surface. In the present study, CO2 and EtOH diffusion coefficients are computed from molecular dynamics (MD) simulations and compared with experimental values derived from the Stokes-Einstein (SE) relation on the basis of viscometry experiments and hydrodynamic radii deduced from former nuclear magnetic resonance (NMR) measurements. These diffusion coefficients steadily increase with temperature and decrease as the concentration of ethanol rises. The agreement between theory and experiment is suitable for CO2. Theoretical EtOH diffusion coefficients tend to overestimate slightly experimental values, although the agreement can be improved by changing the hydrodynamic radius used to evaluate experimental diffusion coefficients. This apparent disagreement should not rely on limitations of the MD simulations nor on the approximations made to evaluate theoretical diffusion coefficients. Improvement of the molecular models, as well as additional NMR measurements on sparkling beverages at several temperatures and ethanol concentrations, would help solve this issue.

Reply to commentaries to willpower with and without effort

Twenty-six commentators from several disciplines have written on the assumption that choice is determined by comparative valuation in a common denominator of reward, the “competitive marketplace.” There was no apparent disagreement that prospective rewards are discounted hyperbolically, although some found that the resulting predictions could come just as well from other models, including the interpretation of delay as risk and analysis in terms of hot versus cold valuation systems. Several novel ideas emerged.

The relationship between residential development land prices and house prices

There exists apparent disagreement between two areas of literature regarding the relationship between house prices and land prices. In the professional literature it is argued that high house prices cause high residential development land prices. In some of the policy literature it is argued that it is land-price increases that are behind increasing house prices. We argue that this is a rather artificial dichotomy and arises from two different ways of thinking about the relationship between land and house prices. To demonstrate this we explore how housing and residential land markets work and how their price responses are interrelated.

Studies on Ostrich (Struthio Camelus) - Review

Ostrich has been reared in Hungary for decades, but we have limited information on this species. The aim of this review was to provide a concise description of the ostrich (Struthio camelus) based on international studies. We were to investigate some of the most relevant parameters, such as egg, meat and skin production. In this critical review we managed to sum up the most significant features and productivity parameters of ostrich and effecting factors. So as to make an accurate description of the species we have to know its morphological, behavioural and physiological characteristics. Ostrich is a very special bird with special nutritional and environmental requirements. Ostrich products, regarding egg, meat and skin are considered luxury products not only in Hungary but also abroad. Though egg has a significant nutritional value, it is mainly used for hatching chicks. In Europe we can expect roughly 40–50 eggs from a hen yearly. Ostrich has a lean meat with high protein and low fat and sodium content, moreover it is rich in minerals and polyunsaturated fatty acids. Having these advantageous qualities, ostrich meat should be part of our healthy diet. Skin production is not important in our country, but there is a special demand for high quality ostrich leather globally. In the future our aim is to conduct a research on some of the parameters. As low production rate and embryo mortality is a great deal of problem in ostrich industry, we need to investigate the incubation environment. There is an apparent disagreement among researchers on optimal slaughter age. This is also an area for further investigation. The value of skin and effecting factors on our climate as well as adaptability of the species are also worth for further investigation together with the nutrition what differs from other ostrich breeding countries. Nowadays, there is a great emphasis placed on animal welfare too.

Descriptive Names and Singular Thought

This chapter is concerned with an apparent disagreement between Gareth Evans (1982) and David Kaplan (1989) with regard to the capacities of names introduced into the language by describing their referents. The question at issue is whether such expressions are potential sources of novel singular thought. While Evans’ response is an emphatic “no,” Kaplan’s response is an equally emphatic “yes.” The chapter attempts to resolve (or rather dissolve) this apparent dispute by suggesting that the two philosophers have importantly different phenomena in mind when they talk of “thoughts”—including (and in particular) singular thoughts. Whereas Evans construes thoughts as mental states, Kaplan construes them as semantic contents. Before concluding, it argues for the superiority of the proposed resolution of the Evans/Kaplan debate over that of Francois Recanati (2012), who invokes his Mental File Framework in an attempt to reconcile the seemingly contrary views of Evans and Kaplan.

On the Clock Paradox

Special Relativity presents before us several thought challenging paradoxes. The most famous one is the clock or twin paradox which arises from the well-known time dilation phenomenon. In this paper, we will give a brief but pedagogical treatment of this paradox. The crucial point is that the relativity of simultaneity, for events happening at different places, plays a fundamental role in understanding the apparent disagreement between the rest and the moving observers. Once this has been taken care of, the disagreement and the paradox would disappear.

Changes in H-reflex amplitude to muscle stretch and lengthening in humans

Spinal reflex excitability is traditionally assessed to investigate neural adjustments that occur during human movement. Different experimental procedures are known to condition spinal reflex excitability. Among these, lengthening movements and static stretching the human triceps have been investigated over the last 50 years. The purpose of this review is to shed light on several apparent incongruities in terms of magnitude and duration of the reported results. In the present review dissimilarities in neuro-spinal changes are examined in relation to the methodologies applied to condition and measure them. Literature that investigated three different conditioning procedures was reviewed: passive dorsiflexion, active dorsiflexion through antagonists shortening and eccentric plantar-flexors contractions. Measurements were obtained before, during and after lengthening or stretching. Stimulation intensities and time delays between conditioning procedures and stimuli varied considerably. H-reflex decreases immediately as static stretching is applied and in proportion to the stretch degree. During dorsiflexions the inhibition is stronger with greater dorsiflexion angular velocity and at lower nerve stimulation intensities, while it is weaker if any concomitant muscle contraction is performed. Within 2 s after a single passive dorsiflexion movement, H-reflex is strongly inhibited, and this effect disappears within 15 s. Dorsiflexions repeated over 1 h and prolonged static stretching training induce long-lasting inhibition. This review highlights that the apparent disagreement between studies is ascribable to small methodological differences. Lengthening movements and stretching can strongly influence spinal neural pathways. Results interpretation, however, needs careful consideration of the methodology applied.

In Healthy Young Men, a Short Exhaustive Exercise Alters the Oxidative Stress Only Slightly, Independent of the Actual Fitness

The aim of the present study was to evaluate the apparent disagreement regarding the effect of a typical cycling progressive exercise, commonly used to assessVO2max, on the kinetics ofex vivocopper induced peroxidation of serum lipids. Thirty-two (32) healthy young men, aged 24–30 years, who do not smoke and do not take any food supplements, participated in the study. Blood was withdrawn from each participant at three time points (before the exercise and 5 minutes and one hour after exercise). Copper induced peroxidation of sera made of the blood samples was monitored by spectrophotometry. For comparison, we also assayed TBARS concentration and the activity of oxidation-related enzymes. The physical exercise resulted in a slight and reversible increase of TBARS and slight changes in the activities of the studied antioxidant enzymes and the lag preceding peroxidation did not change substantially. Most altered parameters returned to baseline level one hour after exercise. Notably, the exercise-induced changes in OS did not correlate with the physical fitness of the subjects, as evaluated in this study (VO2max= 30–60 mL/min/kg). We conclude that in healthy young fit men a short exhaustive exercise alters only slightly the OS, independent of the actual physical fitness.