975 research outputs found

    Evaluación de pastas de Hesperaloe funifera obtenidas con un proceso de bajo consumo energético como material de refuerzo de pastas recicladas

    Get PDF
    The aim of this work is to study the reinforcement capacity of pulps obtained from Hesperaloe funifera using a simple and low energy consumption process (chemi refiner mechanical pulping) once they are added in different percentages to recycled pulps from newspaper and from old corrugated containers (OCC). Pinus radiata kraft pulp was used as a referent reinforcement material. H. funifera acted as a reinforcement material in newspaper and OCC recycled pulps, improving their optical and mechanical properties. While a 25% of H. funifera was the optimal amount added to reinforce the OCC pulp, only a 10% was needed for newspaper pulp. However, the OCC optimal mixture was better reinforced as it showed higher increase in all properties than the optimal newspaper mixture, apart from tensile index. Finally, all mixtures with P. radiata kraft pulp produce handsheet with lower properties, apart from tear index, suggesting than H. funifera is a better reinforcement material.El objetivo de este trabajo es estudiar la capacidad de refuerzo de pastas de Hesperaloe funifera obtenidas mediante un proceso simple de bajo consumo energético (pasteado químico-mecánico de refino) una vez añadidas en diferentes porcentajes a pastas recicladas de periódicos y de cartón ondulado (OCC). Se utilizó como material de refuerzo de referencia pasta kraft de Pinus radiata. H. funifera mejoró las propiedades ópticas y mecánicas de todas las pastas recicladas estudiadas, demostrando su capacidad de refuerzo. Mientras que un 25% de H. funifera fue la cantidad óptima para reforzar la pasta de OCC, sólo un 10% fue necesario para la pasta de periódicos. Sin embargo, la mezcla óptima de OCC mostró un mayor incremento en todas las propiedades que la mezcla óptima de periódicos, a excepción del índice de tracción. Por último, todas las mezclas de pasta kraft de P. radiata proporcionaron hojas con menores propiedades mecánicas, a excepción del índice de desgarro, lo que sugiere que H. funifera es un material de refuerzo más eficaz

    Marginal Damage of Methane Emissions: Ozone Impacts on Agriculture

    Get PDF
    Methane directly contributes to air pollution, as an ozone precursor, and to climate change, generating physical and economic damages to different systems, namely agriculture, vegetation, energy, human health, or biodiversity. The methane-related damages to climate, measured as the Social Cost of Methane, and to human health have been analyzed by different studies and considered by government rulemaking in the last decades, but the ozone-related damages to crop revenues associated to methane emissions have not been incorporated to policy agenda. Using a combination of the Global Change Analysis Model and the TM5-FASST Scenario Screening Tool, we estimate that global marginal agricultural damages range from ~ 423 to 556 2010/tCH4,ofwhich982010/t-CH4, of which 98 2010/t-CH4 occur in the USA, which is the most affected region due to its role as a major crop producer, followed by China, EU-15, and India. These damages would represent 39–59% of the climate damages and 28–64% of the human health damages associated with methane emissions by previous studies. The marginal damages to crop revenues calculated in this study complement the damages from methane to climate and human health, and provides valuable information to be considered in future cost-benefits analyses. © 2023, The Author(s).JS and SW were supported by the U.S. Environmental Protection Agency, under Interagency Agreement DW-089-92459801. The views expressed in this article are purely those of the authors and do not, under any circumstances, represent the views or policies of the U.S. Environmental Protection Agency or the European Commission. JS and SW were supported by the U.S. Environmental Protection Agency, under Interagency Agreement DW-089-92459801. The views expressed in this article are purely those of the authors and do not, under any circumstances, represent the views or policies of the U.S. Environmental Protection Agency or the European Commission

    Obtaining the basic response pattern of physiological time series data : a comparison of methods

    Get PDF
    An understanding of the kinetics of physiological variables such as the heart rate or the rate of change of volume of oxygen uptake is fundamental not only to training methodology and competitive success in sport and exercise, but also to our knowledge of cardiovascular health. A correct and efficient means of interpreting and analyzing the data obtained is of vast importance, as exercise testing is routinely used in both of these areas

    From Invisibility to the Public Sphere: The Hybrid Media Strategy of a New Party (Podemos, Spain, 2014–2015)

    Get PDF
    How does a new party manage to move from invisibility to occupying a central position in the public debate? How does it gain the attention of the mainstream media and recognition by the public and the institutions linked to sociopolitical and economic power? This article examines the media strategy followed by the Spanish party Podemos in its first year of activity. We apply quantitative and longitudinal methods to analyze the attention paid to Podemos by television channels, newspapers, online press, and digital networks. Results show that the party prioritized antagonistic talk shows, infotainment, and self-produced television programs, which combined to create a viral presence on digital networks and led to its leaders appearing on mainstream TV channels. This hybrid strategy took the party from media invisibility to the central public sphere, though traditional dependence on favorable opinion polls and electoral success were also relevant

    Pituitary adenylate cyclase-activating polypeptide (PACAP) inhibits the slow afterhyperpolarizing current sI AHP in CA1 pyramidal neurons by activation multiple signaling pathways

    Get PDF
    The slow afterhyperpolarizing current (sIAHP ) is a calcium-dependent potassium current that underlies the late phase of spike frequency adaptation in hippocampal and neocortical neurons. sIAHP is a well-known target of modulation by several neurotransmitters acting via the cyclic AMP (cAMP) and protein kinase A (PKA)-dependent pathway. The neuropeptide pituitary adenylate cyclase activating peptide (PACAP) and its receptors are present in the hippocampal formation. In this study we have investigated the effect of PACAP on the sIAHP and the signal transduction pathway used to modulate intrinsic excitability of hippocampal pyramidal neurons. We show that PACAP inhibits the sIAHP , resulting in a decrease of spike frequency adaptation, in rat CA1 pyramidal cells. The suppression of sIAHP by PACAP is mediated by PAC1 and VPAC1 receptors. Inhibition of PKA reduced the effect of PACAP on sIAHP , suggesting that PACAP exerts part of its inhibitory effect on sIAHP by increasing camp and activating PKA. The suppression of sIAHP by PACAP was also strongly hindered by the inhibition of p38 MAP kinase (p38 MAPK). Concomitant inhibition of PKA and p38 MAPK indicates that these two kinases act in a sequential manner in the same pathway leading to the suppression of sIAHP . Conversely, protein kinase C is not part of the signal transduction pathway used by PACAP to inhibit sIAHP in CA1 neurons. Our results show that PACAP enhances the excitability of CA1 pyramidal neurons by inhibiting the sIAHP through the activation of multiple signaling pathways, most prominently cAMP/PKA and p38 MAPK. Our findings disclose a novel modulatory action of p38 MAPK on intrinsic excitability and the sIAHP , underscoring the role of this current as a neuromodulatory hub regulated by multiple protein kinases in cortical neurons. © 2013 Wiley Periodicals, Inc

    Progressive myoclonus epilepsy KCNC1 variant causes a developmental dendritopathy

    Get PDF
    OBJECTIVE: Mutations in KCNC1 can cause severe neurological dysfunction, including intellectual disability, epilepsy, and ataxia. The Arg320His variant, which occurs in the voltage-sensing domain of the channel, causes a highly penetrant and specific form of progressive myoclonus epilepsy with severe ataxia, designated myoclonus epilepsy and ataxia due to potassium channel mutation (MEAK). KCNC1 encodes the voltage-gated potassium channel KV 3.1, a channel that is important for enabling high-frequency firing in interneurons, raising the possibility that MEAK is associated with reduced interneuronal function. METHODS: To determine how this variant triggers MEAK, we expressed KV 3.1bR320H in cortical interneurons in vitro and investigated the effects on neuronal function and morphology. We also performed electrophysiological recordings of oocytes expressing KV 3.1b to determine whether the mutation introduces gating pore currents. RESULTS: Expression of the KV 3.1bR320H variant profoundly reduced excitability of mature cortical interneurons, and cells expressing these channels were unable to support high-frequency firing. The mutant channel also had an unexpected effect on morphology, severely impairing neurite development and interneuron viability, an effect that could not be rescued by blocking KV 3 channels. Oocyte recordings confirmed that in the adult KV 3.1b isoform, R320H confers a dominant negative loss-of-function effect by slowing channel activation, but does not introduce potentially toxic gating pore currents. SIGNIFICANCE: Overall, our data suggest that, in addition to the regulation of high-frequency firing, KV 3.1 channels play a hitherto unrecognized role in neuronal development. MEAK may be described as a developmental dendritopathy

    Prioritization of Managed Pork Supply Movements during a FMD Outbreak in the US

    Get PDF
    In the event of a Foot and Mouth Disease (FMD) outbreak in the U.S., local, state, and federal authorities will implement a foreign animal disease emergency response plan restricting the pork supply chain movements and likely disrupting the continuity of the swine industry business. To minimize disruptions of the food supply while providing an effective response in an outbreak, it is necessary to have proactive measures in place to ensure minimal disease spread and maximum continuation of business. Therefore, it is critical to identify candidate movements for proactive risk assessments: those that are both most likely to contribute to disease spread and most necessary for business continuity. To do this, experts from production, harvest, retail, and allied pork industries assessed 30 common pork supply movements for risk of disease spread and industry criticality. The highest priority movements for conducting a risk assessment included the movement of weaned pigs originating from multiple sow farm sources to an offsite nursery or wean to finish facility, the movement of employees or commercial crews, the movement of vaccination crews, the movement of dedicated livestock hauling trucks, and the movement of commercial crews such as manure haulers and feed trucks onto, off, or between sites. These critical movements, along with several others identified in this study, will provide an initial guide for prioritization of risk management efforts and resources to be better prepared in the event of a FMD outbreak in the United States. By specifically and proactively targeting movements that experts agree are likely to spread the disease and are critical to the continuity of business operations, potentially catastrophic consequences in the event of an outbreak can be limited

    Development of nanolubricant based on impregnated multilayer graphene for automotive applications: Analysis of tribological properties

    Full text link
    [EN] This paper shows novel formulations of nanolubricants added with multi-layer graphene (MLG), multi-layer graphene impregnated with copper (MLG-Cu), and multi-layer graphene impregnated with polyaniline (MLG-PANI) for applications in automotive engines. These nanofluids were prepared using commercial motor oil as the base fluid. The tribological properties were measured at 100 degrees C, and significant reductions were found in the coefficient of friction and wear. The concentrations used were 0.5% and 2% by weight, obtaining reductions in the friction coefficient and wear of up to 43% and 63%, respectively, in the case of motor oil with copper-impregnated graphene. All formulations of MLG, MLG-Cu, and MLG-PANI did not show any sedimentation when dispersed in engine oil, even three months after being produced. (C) 2016 Elsevier B.V. All rights reserved.The authors would like to thank Tecnologico de Monterrey (ITESM) through the focus group of Energy and Climate Change for the support of this project and CONACYT for funding the stay at the Universidad Politecnica de Valencia (UPV).Ramon-Raygoza, E.; Rivera-Solorio, C.; Giménez Torres, E.; Maldonado-Cortes, D.; Cardenas-Aleman, E.; Cué-Sampedro, R. (2016). Development of nanolubricant based on impregnated multilayer graphene for automotive applications: Analysis of tribological properties. Powder Technology. 302:363-371. https://doi.org/10.1016/j.powtec.2016.08.072S36337130
    corecore