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As a consequence of the growth of accretionary orogenic belts in central Asia, the high elevation of the East Sayan Mountains concomitant with the plutonic activities in Jom-Bolok and Azas Plateau volcanic fields provide a rare opportunity to unravel lithospheric deformation induced by large-scale tectonic processes such as the passage of thermal plumes. Here we use receiver functions (RFs) to obtain high-resolution images of the 410 km (d410) and 660 km (d660) discontinuities and to measure mantle transition zone (MTZ) thickness. The average apparent depression of the d410 and d660 for a circular area under northern Mongolia and East Sayan are 14 km and 51 km respectively, leading to a significant thicker-than-normal MTZ with a mean value of 37 km. Our results, when incorporated with previous geochemical characteristics, suggest heterogeneous deep mantle materials highlighted by the great depression of the d660, revealing that possible foundered lithospheric remnants have dripped into the MTZ beneath the East Sayan Mountains. Negative thermal anomalies generated by the recycled lithosphere in the MTZ elucidate the prominent lateral undulation of the MTZ discontinuities, and a MTZ thinning beneath the southwest part of the study area is ascribed to the upward small-scale mantle convection initiated by the foundered lithospheric materials. We suggest that the descending lithosphere is due to the hot mantle plumes interacting with base of the mantle lithosphere which provided a viable perspective for the origin of the widespread magmatisms with distinct geochemical signatures in the region. 

Around the world, people increasingly generate data through their everyday activities. Much of this happens unwittingly through sensors, cameras, and other surveillance tools on roads, in cities, and at the workplace. However, how individuals and governments think about privacy varies significantly around the world. In this article, we explore differences between people’s attitudes toward privacy and data collection practices in the United States and the Netherlands, two countries with very different regulatory approaches to governing consumer privacy. Through a factorial vignette survey deployed in the two countries, we identify specific contextual factors associated with concerns regarding how personal data are being used. Using Nissenbaum’s framework of privacy as contextual integrity to guide our analysis, we consider the role that five factors play in this assessment: actors (those using data), data type, amount of data collected, reported purpose of data use, and inferences drawn from the data. Findings indicate nationally bound differences as well as shared concerns and indicate future directions for cross-cultural privacy research. 

AQP7 is one of the four human aquaglyceroporins that facilitate glycerol transport across the cell membrane, a biophysical process that is essential in human physiology. Therefore, it is interesting to compute AQP7's affinity for its substrate (glycerol) with reasonable certainty to compare with the experimental data suggesting high affinity in contrast with most computational studies predicting low affinity. In this study aimed at computing the AQP7-glycerol affinity with high confidence, we implemented a direct computation of the affinity from unbiased equilibrium molecular dynamics (MD) simulations of three all-atom systems constituted with 0.16 M, 4.32 M, and 10.23 M atoms, respectively. These three sets of simulations manifested a fundamental physics law that the intrinsic fluctuations of pressure in a system are inversely proportional to the system size (the number of atoms in it). These simulations showed that the computed values of glycerol-AQP7 affinity are dependent upon the system size (the inverse affinity estimations were, respectively, 47.3 mM, 1.6 mM, and 0.92 mM for the three model systems). In this, we obtained a lower bound for the AQP7-glycerol affinity (an upper bound for the dissociation constant). Namely, the AQP7-glycerol affinity is stronger than 1087/M (the dissociation constant is less than 0.92 mM). Additionally, we conducted hyper steered MD (hSMD) simulations to map out the Gibbs free-energy profile. From the free-energy profile, we produced an independent computation of the AQP7-glycerol dissociation constant being approximately 0.18 mM. 

Around the world, people increasingly generate data through their everyday activities. Much of this also happens unwittingly, thanks to sensors, cameras, and other surveillance tools on the roads, in cities, and in businesses. However, the ways citizens and governments think about privacy vary significantly around the world. In this paper, we explore differences between citizens’ attitudes toward privacy and data collection practices in the U.S. and the Netherlands, an EU member nation. Using a factorial vignette survey methodology, we identify specific contextual factors associated with people’s level of concern about how their data is being used. We consider the role that five factors play in this assessment: actors (those using data), data type and amount, reported purpose for data use, and inferences drawn from the data. These indicate nationally bound differences but likewise point to potentially more globally shared concerns. 

Solid fuel combustion experiments aboard the ISS examine the effects of confinement on a concurrent, purely-forced-flow flame spread in microgravity environment. The results for a thin, cotton-fiberglass-blended textile fabric fuel are presented. Flat baffles of differing materials are used to alter the radiative boundary conditions with transparent polycarbonate, black anodized aluminum (reflectance ~ 0), and highly polished aluminum (reflectance ~ 1). The baffles are parallel to the fuel sheet and placed symmetrically on each side. The inter-baffle distance is varied to change the boundary conditions for the flow. In all tests, samples are ignited at the upstream leading edge and allowed to burn to completion. Results show that the flame reaches a steady length and spread rate at low flow speeds (< 15 cm/s) for all tested inter-baffle distances. As the distance decreases, the flame length and spread rate first increase then decrease showing an optimal inter-baffle distance. For all baffle types, the flame either fails to ignite or extinguishes before reaching the end of the sample when the inter-baffle distance is too small (~ 1 cm). This is attributed to the reduction of oxygen supply to the flame zone and heat loss to the baffles. The results also show at the same inter-baffle distance, flame length and spread rate are highest for polished aluminum baffles, and lowest for transparent polycarbonate baffles. The differences are most prominent at intermediate tested baffle distances. While the radiative heat feedback from the baffles is expected to increase when the baffle distance decreases, the combustion is limited by the reduced oxygen supply. Near this limit, flame lengths and spread rates are similar for all baffle types.