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[Display omitted] • Liquid to solid phase transition of biodiesel was detected via vibrating tube densimeter technique for the first time. • The established procedure for solidification detection could be extended for other amorphous materials. • Solidification of biodiesel was detected by upwards pressurization. • Liquid densities for waste beef tallow FAMEs, FAEEs and FABEs are reported from 286 to 393 K, and pressures up to 137 MPa. • FAMEs had the highest density, while the lowest density was observed for FABEs. Phase behavior and thermophysical properties of biodiesel at high pressure and high temperature are limited in the literature. These are useful to develop models and to understand their behavior having in mind the use of biodiesel in engines. Liquid to solid phase transitions, by using a vibrating tube densimeter, along with densities of three beef tallow fatty acid alkyl esters were studied in this work. Measurements of the oscillating period for each biofuel were carried out in a modular array constituted by two vibrating tube densimeters coupled in series and connected to a single loading cell. The oscillating period was converted to density by the forced path mechanical calibration (FPMC) method. Experimental liquid density sets for three beef tallow biodiesel samples based on fatty acid alkyl esters (FAAEs) are reported for the first time for pressures up to 137 MPa. These biofuels, named fatty acid methyl esters (FAMEs), fatty acid ethyl esters (FAEEs) and fatty acid butyl esters (FABEs), were measured in the temperature range of 286–393 K. The detection procedure for the beginning of the high-pressure solidification was focused on the beef tallow FABEs sample based upon its lower cloud point (CP FABEs = 281.15 K) in comparison with the reported property for the other esters (CP FAEEs = 289.15 K, CP FAMEs = 291 K) with the same feedstock; therefore, the conditions for the metastable liquid to solid phase transition associated to the effect of high pressure was detailed for waste beef tallow butyl ester biodiesel by performing step-by-step compressions in the interval of 286.20–298.13 K and with the help of the vibrating tube densimeters. FABEs had the lower density in contrast with FAEEs and FAMEs, this one being the denser biofuel. Modeling of liquid density data was performed by the perturbed-chain statistical associating fluid theory (PC-SAFT) Equation of State and the Tammann-Tait equation with maximum absolute average deviations of 0.15 % and 0.05 %, respectively. Both models were applied for correlating the thermodynamic derived properties of the fluid phase: isobaric thermal expansivity and isothermal compressibility. [ABSTRACT FROM AUTHOR]

Abstract: Gender identity—one''s sense of being a man or a woman—is a fundamental perception experienced by all individuals that extends beyond biological sex. Yet, what contributes to our sense of gender remains uncertain. Since individuals who identify as transsexual report strong feelings of being the opposite sex and a belief that their sexual characteristics do not reflect their true gender, they constitute an invaluable model to understand the biological underpinnings of gender identity. We analyzed MRI data of 24 male-to-female (MTF) transsexuals not yet treated with cross-sex hormones in order to determine whether gray matter volumes in MTF transsexuals more closely resemble people who share their biological sex (30 control men), or people who share their gender identity (30 control women). Results revealed that regional gray matter variation in MTF transsexuals is more similar to the pattern found in men than in women. However, MTF transsexuals show a significantly larger volume of regional gray matter in the right putamen compared to men. These findings provide new evidence that transsexualism is associated with distinct cerebral pattern, which supports the assumption that brain anatomy plays a role in gender identity. [Copyright &y& Elsevier]

Abstract: Biological differences between men and women contribute to many sex-specific illnesses and disorders. Historically, it was argued that such differences were largely, if not exclusively, due to gonadal hormone secretions. However, emerging research has shown that some differences are mediated by mechanisms other than the action of these hormone secretions and in particular by products of genes located on the X and Y chromosomes, which we refer to as direct genetic effects. This paper reviews the evidence for direct genetic effects in behavioral and brain sex differences. We highlight the ‘four core genotypes’ model and sex differences in the midbrain dopaminergic system, specifically focusing on the role of Sry. We also discuss novel research being done on unique populations including people attracted to the same sex and people with a cross-gender identity. As science continues to advance our understanding of biological sex differences, a new field is emerging that is aimed at better addressing the needs of both sexes: gender-based biology and medicine. Ultimately, the study of the biological basis for sex differences will improve healthcare for both men and women. [Copyright &y& Elsevier]

Dmanisi (Georgia) is one of the oldest Early Paleolithic sites discovered out of Africa. In addition, it is the best site to understand the first Homo deme out of Africa and the first hominin occupation of Central to Western Eurasia. It has produced more than 40 hominin remains, including several very informative skulls, found in direct association with faunal remains and numerous lithic artifacts. To date, fossil amphibians and reptiles are one of the few proxies that have been used to propose quantitative climate reconstructions for the time where the hominins were living at Dmanisi. The aim of the present study is to review and amplify the previous paleoclimatic interpretation given by Blain et al. (2014) , with an enhanced methodology using geographic information system and based on uncertain distribution area-occupied distribution area discrimination technique. This procedure permits to approach to a more precise common species distribution area and then using the WorldClim v. 2.1 climate database to propose for the first time monthly reconstructions for temperature and rainfall, in addition to annual parameters. The same technique is used to infer dominant ecoregions through the study area and potential tree coverage. Dmanisi climate is newly reconstructed as warm and semi-arid, similar to the present-day Mediterranean climate. New estimates however suggest warmer temperatures than previously reconstructed, together with a slightly higher but much more irregular amount of rainfall. The aridity indexes suggest a six months dry period, from May to October. Associated regional paleoenvironment is mainly characterized by Mediterranean forests, woodlands, and scrub, and the potential tree coverage is around 25%, that is, much less forested than today. New estimates agree with the 'Iberian' hominin ecological model, and with other proxies (large mammals, small mammals and archaeobotanical remains) that indicate a period of increased aridity contemporaneous with human occupations of the site. • Dmanisi is one of the oldest Early Paleolithic sites discovered out of Africa. • Climate is newly reconstructed as Mediterranean warm and semi-arid. • New estimates however suggest warmer temperatures than previously reconstructed. • Paleoenvironment is characterized by Mediterranean forests, woodlands, and scrub. • Mediterranean biome was a suitable place for early hominins as early as 1.8 Ma. [ABSTRACT FROM AUTHOR]