Formation of Two Glass Phases in Binary Cu-Ag Liquid

The glass transition is alternatively described as either a dynamic transition in which there is a dramatic slowing down of the kinetics, or as a thermodynamic phase transition. To examine the physical origin of the glass transition in fragile Cu-Ag liquids, we employed molecular dynamics (MD) simulations on systems in the range of 32,000 to 2,048,000 atoms. Surprisingly, we identified a 1st order freezing transition from liquid (L) to metastable heterogenous solid-like phase, denoted as the G-glass, when a supercooled liquid evolves isothermally below its melting temperature at deep undercooling. In contrast, a more homogenous liquid-like glass, denoted as the L-glass, is achieved when the liquid is quenched continuously to room temperature with a fast cooling rate of ∼10¹¹ K/sec. We report a thermodynamic description of the L-G transition and characterize the correlation length of the heterogenous structure in the G-glass. The shear modulus of the G-glass is significantly higher than the L-glass, suggesting that the first order L-G transition is linked fundamentally to long-range elasticity involving elementary configurational excitations in the G-glass

Endocrinologic Control of Men's Sexual Desire and Arousal/Erection

Several hormones and neurotransmitters orchestrate men's sexual response, including the appetitive (sexual desire) and consummative (arousal and penile erection) phases. AIM: To provide an overview and recommendations regarding endocrinologic control of sexual desire and arousal and erection and their disturbances. METHODS: Medical literature was reviewed by the subcommittee of the International Consultation of Sexual Medicine, followed by extensive internal discussion, and then public presentation and discussion with other experts. The role of pituitary (prolactin, oxytocin, growth hormone, and α-melanocyte-stimulating hormone), thyroid, and testicular hormones was scrutinized and discussed. MAIN OUTCOME MEASURES: Recommendations were based on grading of evidence-based medical literature, followed by interactive discussion. RESULTS: Testosterone has a primary role in controlling and synchronizing male sexual desire and arousal, acting at multiple levels. Accordingly, meta-analysis indicates that testosterone therapy for hypogonadal individuals can improve low desire and erectile dysfunction. Hyperprolactinemia is associated with low desire that can be successfully corrected by appropriate treatments. Oxytocin and α-melanocyte-stimulating hormone are important in eliciting sexual arousal; however, use of these peptides, or their analogs, for stimulating sexual arousal is still under investigation. Evaluation and treatment of other endocrine disorders are suggested only in selected cases. CONCLUSION: Endocrine abnormalities are common in patients with sexual dysfunction. Their identification and treatment is strongly encouraged in disturbances of sexual desire and arousal

Drying kinetics and physico-chemical quality of mango slices

Mango (Mangifera indica L.) is an important tropical fruit consumed worldwide and grown in Italy only in Sicily, where the areas of the Tyrrhenian coast have proved to be suitable to produce valuable fruits. Mango fruit has a pleasant aroma and taste, which are important qualities for consumer’s sensorial acceptance. However, they are highly perishable, prone to progressive undesired changes if stored untreated, resulting in around 25% postharvest losses, which is further increased during storage and transportation. An alternative for reducing the above-mentioned undesired changes is the dehydration of the cut fruit, which reduce the fruit water activity, thereby avoiding the deteriorative process and extending the shelf-life. This study investigates the effect of dehydration at different temperatures (50, 60 and 70°C) on drying kinetics and volatile compounds of two cultivars (Keitt and Osteen) of mango fruits cultivated in Sicily. Significant losses of volatile constituents of fresh mango occurred at higher temperature, especially for the Osteen cultivar. A diffusion model including the effect of shrinkage is also proposed, which may be used to describe drying behaviour of fruits and to define the optimal drying conditions.. Experimental data of the moisture ratio during drying were well predicted by the model

Evaluating the potential of marginal lands available for sustainable cellulosic biofuel production in Italy

The European Union aims to provide as much as one quarter of its transportation fuels via biofuels derived from renewable sources by 2030. To put this into perspective, the Italian government has recently established an ambitious goal to support the wider uptake of advanced second-generation biofuels, including cellulosic biofuels for the transportation sector. A sustainable way forward is to grow perennial biomass crops on marginal lands, however the nationwide availability of those lands for lignocellulosic feedstock production remains uncertain. We identify and evaluate the potential of marginal lands in Italy to produce sizeable amounts of biomass for sustainable cellulosic biofuel production while limiting land use conflicts and negative ecological impacts. We applied spatial multi-criteria decision analysis techniques in geographic information systems to ultimately generate spatially-explicit national land suitability and availability maps at a fine resolution (250-m). We selected a broad range of leading cellulosic biomass crops that includes poplar (Populus × canadensis Moench), willow (Salix alba Linnaeus), black locust (Robinia pseudoacacia Linnaeus), giant reed (Arundo donax Linnaeus), and vetiver grass (Chrysopogon zizanioides Linnaeus). Based on marginality criteria, our results suggest that such biomass plantations of perennial grasses and short rotation trees may produce 3.1–27.4 billion liters of cellulosic ethanol per year from 462,265 to 2,811,064 million hectares of available marginal lands. This estimated production may fulfill 7.8–69.1% of Italy's current liquid transportation fuel consumption, constrained by the requirement that each modelled location be within 70 km of a potential cellulosic biorefinery. Collectively, this study provides the cornerstone of efforts to rationally meet Italy's need for renewable fuels in a sustainable low-carbon economy future

Historical roots and the evolving science of forest management under a systemic perspective

In recent history, both a growing awareness of how scientific and societal uncertainty impacts management decisions and of the intrinsic value of nature have suggested new approaches to forest management, with a growing debate in forest science over the need for a paradigmatic shift from the classic conventional world view, based on determinism, predictability, and output-oriented management, towards a world view that has roots in complex adaptive systems theory and is consistent with a nature-based ethic. A conceptual framework under this context is provided by systemic silviculture. In this discussion, we analyze how this approach can be linked to three fundamental moments of the history of forestry and forest science: the Dauerwald theory, Gurnaud's control method, and the origins of environmental ethics. Relationships with the recent history of forest management science and current research perspectives are also highlighted.4n

EL METANO Y LA GANADERÍA BOVINA EN MÉXICO: ¿PARTE DE LA SOLUCIÓN Y NO DEL PROBLEMA?

Cattle production in Mexico uses nearly 58 % of the territory, which makes it mainly extensive. Despite being the main origin of greenhouse gases (GHG), extensive cattle production has a high mitigation potential (20-40 % of current levels) if practices such as pasture management, adequate nutritional management and genetic selection are implemented. Furthermore, grasslands and pastures used in extensive production systems have a role to play in carbon sequestration which would help balance the impact of such systems in the environment. However, in order to adequately account for emission of cattle production systems, environmental services that these production systems provide need to be also recorded. Additionally, work on individual mitigation at animal level is still the main focus of most of research carried out to reduce environmental impact of cattle production. Researchers can now work on determining effective GHG mitigation methods and strategies at animal and farm levels to allow cattle production systems sustainabilty in the long term. The strategies developed need to minimise environmental impact of cattle production striking a balance between productivity, ecosystemic health and wellbeing of farmers and local communities.El 73 % del territorio de la Republica Mexicana se utiliza para las actividades agropecuarias, con el 58 % de la superficie empleado como agostaderos, en donde la producción de bovinos se basa en pastoreo y aunque la producción bovina extensiva es una de las que mayores emisiones de gases efecto invernadero (GEI) produce, también es la que mayor capacidad de mitigación tiene. El potencial de mitigación en sistemas de producción bovina puede ser mayor de 2040 % de los niveles actuales, siempre que se puedan adaptar prácticas destinadas a mejorar el manejo de las praderas, la alimentación de los animales y mejoramiento genético. La ganadería extensiva tiene un gran potencial de secuestro de carbono a través de las praderas. El potencial de mitigación del impacto ambiental, y no solo de las emisiones, puede ser mayor en los sistemas en pastoreo si se toman en cuenta todos los posibles servicios ambientales que estos prestan. Lograr un balance en la emisión y mitigación a nivel individual (animal), de granja y cadena productiva hará que los sistemas de producción bovina sean más eficientes y sustentables a largo plazo, permitiendo reducir la emisiones de gases de efecto invernadero, garantizando el bienestar del ecosistema y de las poblaciones rurales