Renal sodium retention in pre-ascitic cirrhosis: the more we know about the puzzle, the more it becomes intricate.

Ascites develops in 5–10% of patients with compensated cirrhosis per year and carries an ominous prognosis [1] . The appropriate management and possible prevention of this complication obvi- ously depends on an in-depth knowledge of ascites pathophysiol- ogy, which remains somewhat elusive despite many studies that have addressed the topic over decades. There is no doubt that post-sinusoidal portal hypertension is the main ''local" pathoge- netic factor, and renal sodium retention is the main ''systemic" event leading to a positive fluid balance and, ultimately, ascites formation. However, uncertainties surround both the efferent (that is the factors/systems promoting renal sodium retention) and afferent (that is the factors that activate efferent mecha- nisms) factors associated with renal sodium handling abnormal- ities [2] . Sodium balance has been demonstrated to become positive before ascites formation both in animal models of cirrho- sis and humans [3–6] . Study of the early mechanisms leading to ascites would help unveil its pathophysiology in a stage of the disease where further complications involving systemic hemody- namics and renal function may act as confounding factors. In this issue of the Journal of Hepatology, Sansoè and co-workers pres- ent a fine study on an efferent mechanism potentially leading to renal sodium retention in pre-ascitic cirrhosi

Psychology of sport injury rehabilitation: a review of models and interventions

Santi, G. & Pietrantoni, L. (2013) Psychology of sport injury rehabilitation: a review of models and interventions. J. Hum. Sport Exerc., 8(4), pp. 1029-1044. The aim of this review is to provide the state of the art about the psychology of sport injury rehabilitation by analyzing the most recent literature and research on this field. In the first part, we presented theoretical models contextualizing the sport injury, the motivational process underlying the recovery, and the influence of social and contextual factors. The second part focuses on the possible psychological interventions and their effect on the rehabilitation process. In conclusion, some gaps in the current literature have been highlighted and directions for future research have been provided

Energy and water vapor transport across a simplified cloud-clear air interface

We consider a simplified physics of the could interface where condensation, evaporation and radiation are neglected and momentum, thermal energy and water vapor transport is represented in terms of the Boussinesq model coupled to a passive scalar transport equation for the vapor. The interface is modeled as a layer separating two isotropic turbulent regions with different kinetic energy and vapor concentration. In particular, we focus on the small scale part of the inertial range as well as on the dissipative range of scales which are important to the micro-physics of warm clouds. We have numerically investigated stably stratified interfaces by locally perturbing at an initial instant the standard temperature lapse rate at the cloud interface and then observing the temporal evolution of the system. When the buoyancy term becomes of the same order of the inertial one, we observe a spatial redistribution of the kinetic energy which produce a concomitant pit of kinetic energy within the mixing layer. In this situation, the mixing layer contains two interfacial regions with opposite kinetic energy gradient, which in turn produces two intermittent sublayers in the velocity fluctuations field. This changes the structure of the field with respect to the corresponding non-stratified shearless mixing: the communication between the two turbulent region is weak, and the growth of the mixing layer stops. These results are discussed with respect to experimental results with and without stratification.Comment: 12 pages, 8 figure

Speed Limit: Obey, or Not Obey?

It is commonly expected that drivers maintain a driving speed that is lower than or around the posted speed limit, as failure to obey may result in safety risks and fines. By taking randomly selected road segments as examples, this study compares the percentages of speeding vehicles in five countries worldwide, namely, two European countries (Germany and Italy), two Asian countries (Japan and China), and one North American country (the United States). Contrary to expectations, our results show that more than 80% of drivers violate the posted speed limits in the studied road segments in Italy, Japan, and the United States. In particular, a significant portion (45.3%) of drivers in Italy exceed the posted speed limit by a substantial margin (30 km/h), while few speeding vehicles are observed in the road segment examined in China. Meanwhile, it is found that drivers on low-speed-limit roads are more likely to exceed the posted speed limit, particularly when there are fewer on-road vehicles. The comparison of different countries' speeding fines indicates that for the purpose of preventing speeding, increasing fines (as Italy has done) is less effective than enhancing supervision (as China has done). The findings remind law enforcement agencies and traffic authorities of the importance of the supervision of driver's behavior and the necessity of revisiting the rationale for the current speed limit settings

On the Color-Metallicity Relation of the Red Clump and the Reddening Toward the Magellanic Clouds

The zero point of the reddening toward the Large Magellanic Cloud (LMC) has been the subject of some dispute. Its uncertainty propagates as a systematic error for methods which measure the extragalactic distance scale through knowledge of the absolute extinction of LMC stars. In an effort to resolve this issue, we used three different methods to calibrate the most widely-used metric to predict LMC extinction, the intrinsic color of the red clump, $(V-I)_{RC,0}$, for the inner $\sim$3 degrees of that galaxy. The first approach was to empirically calibrate the color zeropoints of the BaSTI isochrones over a wide metallicity range of ${\Delta}\rm{[Fe/H]} \approx 1.10$ using measurements of red clump stars in 47 Tuc, the Solar Neighborhood, and NGC 6791. From these efforts we also measure these properties of the Solar Neighborhood red clump, ($V-I$, $G_{BP}-K_{s}$, $G-K_{s}$, $G_{RP}-K_{s}$, $J-K_{s}$, $H-K_{s}$, $M_{I}$, $M_{Ks}$)$_{RC,0} =$ (1.02, 2.75, 2.18, 1.52, 0.64, 0.15, $-$0.23, $-$1.63). The second and third methods were to compare the observed colors of the red clump to those of Cepheids and RR Lyrae in the LMC. With these three methods, we estimated the intrinsic color of the red clump of the LMC to be $(V-I)_{RC,0,\rm{LMC}} = \{ \approx 0.93,0.91 \pm 0.02,0.89 \pm 0.02\}$ respectively, and similarly using the first and third method we estimated $(V-I)_{RC,0,\rm{SMC}} = \{\approx 0.85,0.84 \pm 0.02 \}$ respectively for the Small Magellanic Cloud. We estimate the luminosities to be $M_{I,RC,\rm{LMC}}=-0.26$ and $M_{I,RC,\rm{SMC}}=-0.37$. We show that this has important implications for recent calibrations of the tip of the red giant branch in the Magellanic Clouds used to measure $H_0$.Comment: 20 pages, 5 figures, 4 tables. Accepted for Publication in The Astrophysical Journal as of February 9th, 202

Flooding Time in Opportunistic Networks under Power Law and Exponential Inter-Contact Times

Performance bounds for opportunistic networks have been derived in a number of recent papers for several key quantities, such as the expected delivery time of a unicast message, or the flooding time (a measure of how fast information spreads). However, to the best of our knowledge, none of the existing results is derived under a mobility model which is able to reproduce the power law+exponential tail dichotomy of the pairwise node inter-contact time distribution which has been observed in traces of several real opportunistic networks. The contributions of this paper are two-fold: first, we present a simple pairwise contact model -- called the Home-MEG model -- for opportunistic networks based on the observation made in previous work that pairs of nodes in the network tend to meet in very few, selected locations (home locations); this contact model is shown to be able to faithfully reproduce the power law+exponential tail dichotomy of inter-contact time. Second, we use the Home-MEG model to analyze flooding time in opportunistic networks, presenting asymptotic bounds on flooding time that assume different initial conditions for the existence of opportunistic links. Finally, our bounds provide some analytical evidences that the speed of information spreading in opportunistic networks can be much faster than that predicted by simple geometric mobility models

Volatiles from steam-distilled leaves of some plant species from Madagascar and New Zealand and evaluation of their biological activity.

Steam-distilled aerial parts of Ravensara Aromatica and Cinnamomum camphora from Madagascar and Leptospermum scoparium from New Zealand have been subjected to qualitative and quantitative analysis by means of GC techniques. This allowed the elucidation of conflicting data present in the available literature for these species. Also, the biological activity in vitro was evaluated by measuring MICs and GIZs

Organoselenium Compounds as Phytochemicals from the Natural Kingdom.

Selenium is naturally present in soils but it is also produced by pollution from human activities into the environment. Its incorporation into plants affords organoselenium metabolites that, depending on the nature of the molecules and the plant species, can be incorporated into proteins, stored or eliminated by volatilization. The possibility to use the selenium metabolism of some plants as a method for bioremediation and, at the main time, as a source of selenated phytochemicals is here discussed taking into consideration the growing interest in organic selenium derivatives as new potential therapeutic agents