859 research outputs found

    A life cycle environmental impact comparison between traditional, hybrid, and electric vehicles in the european context

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    Global warming (GW) and urban pollution focused a great interest on hybrid electric vehicles (HEVs) and battery electric vehicles (BEVs) as cleaner alternatives to traditional internal combustion engine vehicles (ICEVs). The environmental impact related to the use of both ICEV and HEV mainly depends on the fossil fuel used by the thermal engines, while, in the case of the BEV, depends on the energy sources employed to produce electricity. Moreover, the production phase of each vehicle may also have a relevant environmental impact, due to the manufacturing processes and the materials employed. Starting from these considerations, the authors carried out a fair comparison of the environmental impact generated by three different vehicles characterized by different pro-pulsion technology, i.e., an ICEV, an HEV, and a BEV, following the life cycle analysis methodology, i.e., taking into account five different environmental impact categories generated during all phases of the entire life of the vehicles, from raw material collection and parts production, to vehicle assembly and on\u2010road use, finishing hence with the disposal phase. An extensive scenario analysis was also performed considering different electricity mixes and vehicle lifetime mileages. The results of this study confirmed the importance of the life cycle approach for the correct determination of the real impact related to the use of passenger cars and showed that the GW impact of a BEV during its entire life amounts to roughly 60% of an equivalent ICEV, while acidifying emissions and par-ticulate matter were doubled. The HEV confirmed an excellent alternative to ICEV, showing good compromise between GW impact (85% with respect to the ICEV), terrestrial acidification, and par-ticulate formation (similar to the ICEV). In regard to the mineral source deployment, a serious concern derives from the lithium\u2010ion battery production for BEV. The results of the scenario analysis highlight how the environmental impact of a BEV may be altered by the lifetime mileage of the vehicle, and how the carbon footprint of the electricity used may nullify the ecological advantage of the BEV

    Septin Phosphorylation and Coiled-Coil Domains Function in Cell and Septin Ring Morphology in the Filamentous Fungus Ashbya Gossypii

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    Septins are a class of GTP-binding proteins conserved throughout many eukaryotes. Individual septin subunits associate with one another and assemble into heteromeric complexes that form filaments and higher-order structures in vivo. The mechanisms underlying the assembly and maintenance of higher-order structures in cells remain poorly understood. Septins in several organisms have been shown to be phosphorylated, although precisely how septin phosphorylation may be contributing to the formation of high-order septin structures is unknown. Four of the five septins expressed in the filamentous fungus, Ashbya gossypii, are phosphorylated, and we demonstrate here the diverse roles of these phosphorylation sites in septin ring formation and septin dynamics, as well as cell morphology and viability. Intriguingly, the alteration of specific sites in Cdc3p and Cdc11p leads to a complete loss of higher-order septin structures, implicating septin phosphorylation as a regulator of septin structure formation. Introducing phosphomimetic point mutations to specific sites in Cdc12p and Shs1p causes cell lethality, highlighting the importance of normal septin modification in overall cell function and health. In addition to discovering roles for phosphorylation, we also present diverse functions for conserved septin domains in the formation of septin higher-order structure. We previously showed the requirement for the Shs1p coiled-coil domain in limiting septin ring size and reveal here that, in contrast to Shs1p, the coiled-coil domains of Cdc11p and Cdc12p are required for septin ring formation. Our results as a whole reveal novel roles for septin phosphorylation and coiled-coil domains in regulating septin structure and function

    Measuring Masculinity in Men With Chronic Disease

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    © The Author(s) 2019. The Masculinity in Chronic Disease Inventory (MCD-I) is a new measure of internalized masculine beliefs previously validated in the context of prostate cancer. The present study assessed the validity of the MCD-I in men with other chronic diseases to explore its potential for wider application. A cross-sectional survey of 633 men aged 47–93 years old (M = 68 years), of whom 68% reported ≥2 chronic conditions, was conducted. Measures included the MCD-I and Erectile Function. Exploratory and confirmatory factor analyses were performed followed by tests for discriminant validity. A five-factor structure was confirmed that explained 60% of the variance, with good to excellent reliabilities (α = 0.68–0.93) for the domains of Optimistic Action, Sexual Importance/Priority, Family Responsibilities, Emotional Self-Reliance, and Strength/Fitness. The MCD-I is a valid measure of internalized masculine beliefs for men with chronic disease that appears sensitive to age and to sexual health. The tailoring of health services for men can be guided by MCD-I outcomes to ensure gender-sensitized men’s health interventions

    Micron-Scale Plasma Membrane Curvature is Recognized by the Septin Cytoskeleton

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    Cells change shape in response to diverse environmental and developmental conditions, creating topologies with micron-scale features. Although individual proteins can sense nanometer-scale membrane curvature, it is unclear if a cell could also use nanometer-scale components to sense micron-scale contours, such as the cytokinetic furrow and base of neuronal branches. Septins are filament-forming proteins that serve as signaling platforms and are frequently associated with areas of the plasma membrane where there is micron-scale curvature, including the cytokinetic furrow and the base of cell protrusions. We report here that fungal and human septins are able to distinguish between different degrees of micron-scale curvature in cells. By preparing supported lipid bilayers on beads of different curvature, we reconstitute and measure the intrinsic septin curvature preference. We conclude that micron-scale curvature recognition is a fundamental property of the septin cytoskeleton that provides the cell with a mechanism to know its local shape

    Esperimento di rimozione degli ammassi mucillaginosi della microalga alloctona <i>Chrysophaeum taylorii</i> Lewis &amp; Bryan = Experiment of removal of the mucilaginous aggregates by the alien microalga <i>Chrysophaeum taylorii</i> Lewis &amp; Bryan

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    A manipulative experiment was carried out in a small bay of Tavolara Punta Coda Cavallo Marine Protected Area in order to investigate the triggers for formation and storage of the macroscopic mucilaginous aggregates of the benthic microalga Chrisophaeum taylorii Lewis &amp; Bryan (Pelagophyceae) and to test the efficacy of mucillage removal

    Septin assemblies form by diffusion-driven annealing on membranes

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    Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 111 (2014): 2146-2151, doi:10.1073/pnas.1314138111.Septins assemble into filaments and higher-order structures that act as scaffolds for diverse cell functions including cytokinesis, cell polarity, and membrane remodeling. Despite their conserved role in cell organization, little is known about how septin filaments elongate and are knit together into higher-order assemblies. Using fluorescence correlation spectroscopy (FCS), we determined that cytosolic septins are in small complexes suggesting that septin filaments are not formed in the cytosol. When the plasma membrane of live cells is monitored by total internal reflection fluorescence (TIRF) microscopy, we see that septin complexes of variable size diffuse in two dimensions. Diffusing septin complexes collide and make end-on associations to form elongated filaments and higher-order structures, an assembly process we call annealing. Septin assembly by annealing can be reconstituted in vitro on supported lipid bilayers with purified septin complexes. Using the reconstitution assay, we show that septin filaments are highly flexible, grow only from free filament ends and do not exchange subunits in the middle of filaments. This work shows for the first time that annealing is an intrinsic property of septins in the presence of membranes and demonstrates that cells exploit this mechanism to build large septin assemblies.This project was supported with funding from by NSF (MCB-507511, ASG) and NIH (GM100160, TT and ASG), and Colwin, Lemann and Spiegel summer fellowships and The Nikon Award for summer investigation at MBL in Woods Hole, MA (ASG) and instrument support from Micro Video Instruments (MVI).2014-07-2
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