43 research outputs found

    Pressure anisotropy generation in a magnetized plasma configuration with a shear flow velocity

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    The nonlinear evolution of the Kelvin Helmholtz instability in a magnetized plasma with a perpendicular flow close to, or in, the supermagnetosonic regime can produce a significant parallel-to-perpendicular pressure anisotropy. This anisotropy, localized inside the flow shear region, can make the configuration unstable either to the mirror or to the firehose instability and, in general, can affect the development of the KHI. The interface between the solar wind and the Earth's magnetospheric plasma at the magnetospheric equatorial flanks provides a relevant setting for the development of this complex nonlinear dynamics.Comment: 11 pages, 7 figures, submitted to Plasma Phys. Control. Fusio

    VARIATION IN MEAT QUALITY CHARACTERISTICS BETWEEN LANDRACE AND SICILIAN PIGS

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    This study compared the meat quality of Sicilian and Landrace pigs breeds and supported these results with biochemical and histological measurements on the samples collected from the m. Longissimus Dorsi, at the level of the 8th thoracic vertebra, before electrical stimulation. Twenty clinically healthy swine, 10 male (5 for each pig breed) and 10 female (5 for each pig breed), were slaughtered at 1 year of age at a body mass of 135±10 kg and 150±10 respectively for Sicilian and Landrace pigs. Particularly on the muscle considered the morphometric characteristics of FG (fast glycolytic), FOG (fast oxidative glycolytic) and SO (slow oxidative) fibre types and their percentage were determined. Measurements related to myofibrillar fragmentation, sarcomere length and connective tissue properties gave convincing support. Sicilian pig produced more tender meat than Landrace, mainly due to favourable calpain-to-calpastatin ratios

    Harmonizing methods to account for soil nitrous oxide emissions in Life Cycle Assessment of agricultural systems

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    CONTEXT: Worldwide greenhouse gas emissions (GHG) reached 59 Gt of COeq in 2019 and agricultural soils are the primary source of NO emissions. Life cycle assessments (LCA) have been successful in assessing GHG from agricultural systems. However, no review and harmonization attempt has been focused on soil NO emissions, despite the need to improve LCA methodologies for assessing GHG in agricultural LCA. OBJECTIVE: We therefore undertook a review and harmonization of existing methods to account for soil NO emissions in LCA of agricultural systems and products: i) to compare current methods used in LCA; ii) to identify advantages and iii) disadvantages of each method in LCA; iv) to suggest recommendations for LCA of agricultural systems; v) to identify research needs and potential methodological developments to account for soil NO emissions in the LCA of agricultural systems. In this paper, we consider as soil NO emissions, those originated from soils in relation to fertilisers (organic and manufactured), crop residues, land use/land management change, grassland management, manure and slurry applications and from grazing animals. METHODS: The approach adopted was based on two anonymous expert surveys and a series of expert workshops (n = 21) to define general and specific criteria to review LCA methods for GHG emissions used in LCA of agricultural systems. A broad list of keywords and search criteria was used as the research involved GHG assessment in agricultural LCA. Reviewed papers and methodology were then assessed by LCA and soil NO emission experts (n = 14). RESULTS AND DISCUSSION: >25,000 scientific papers and reports were identified, 1175 were screened, 263 included in the final review and 31 scientific papers were related to soil NO emissions. The results showed that a high level of accuracy corresponded to a low level of applicability and vice versa, following the assessment framework developed in this work through participatory approaches. SIGNIFICANCE: The choice of LCA methods, critical for high quality LCA of agricultural systems, should be based on the assessment objectives, data availability and expertise of the LCA practitioner. However, it is preferable to use DNDC model after calibration and validation or direct field measurements, considering system effects. When necessary data are lacking, IPCC tier 2 methodology where available should be used, otherwise 2019 IPCC Tier 1 methodology. This LCA method development should be synchronous with improvements of quantification methods and the assessment of a wider range of agricultural management practices and systems.This research has been developed within the PATHWAYS project, funded by the European Union’s Horizon 2020 Research and Innovation Programme European Union through Horizon 2020 Research and Innovation Programme under grant agreement No 101000395

    Fragmentation processes of ionized 5-fluorouracil in the gas phase and within clusters

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    We have measured mass spectra for positive ions produced from neutral 5-fluorouracil by electron impact at energies from 0 to 100 eV. Fragment ion appearance energies of this (radio-)chemotherapy agent have been determined for the first time and we have identified several new fragment ions of low abundance. The main fragmentations are similar to uracil, involving HNCO loss and subsequent HCN loss, CO loss, or FCCO loss. The features adjacent to these prominent peaks in the mass spectra are attributed to tautomerization preceding the fragmentation and/or the loss of one or two additional hydrogen atoms. A few fragmentions are distinct for 5-fluorouracil compared to uracil, most notably the production of the reactive moiety CF+. Finally, multiphoton ionization mass spectra are compared for 5-fluorouracil from a laser thermal desorption source and from a supersonic expansion source. The detection of a new fragment ion at 114 u in the supersonic expansion experiments provides the first evidence for a clustering effect on the radiation response of 5-fluorouracil. By analogy with previous experiments and calculations on protonated uracil, this is assigned to NH3 loss from protonated 5-fluorouracil

    Building consensus on water use assessment of livestock production systems and supply chains: outcome and recommendations from the FAO LEAP partnership.

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    The FAO Livestock Environmental Assessment and Performance (LEAP) Partnership organised a Technical Advisory Group (TAG) to develop reference guidelines on water footprinting for livestock production systems and supply chains. The mandate of the TAG was to i) provide recommendations to monitor the environmental performance of feed and livestock supply chains over time so that progress towards improvement targets can be measured, ii) be applicable for feed and water demand of small ruminants, poultry, large ruminants and pig supply chains, iii) build on, and go beyond, the existing FAO LEAP guidelines and iv) pursue alignment with relevant international standards, specifically ISO 14040 (2006)/ISO 14044 (2006), and ISO 14046 (2014). The recommended guidelines on livestock water use address both impact assessment (water scarcity footprint as defined by ISO 14046, 2014) and water productivity (water use efficiency). While most aspects of livestock water use assessment have been proposed or discussed independently elsewhere, the TAG reviewed and connected these concepts and information in relation with each other and made recommendations towards comprehensive assessment of water use in livestock production systems and supply chains. The approaches to assess the quantity of water used for livestock systems are addressed and the specific assessment methods for water productivity and water scarcity are recommended. Water productivity assessment is further advanced by its quantification and reporting with fractions of green and blue water consumed. This allows the assessment of the environmental performance related to water use of a livestock-related system by assessing potential environmental impacts of anthropogenic water consumption (only ?blue water?); as well as the assessment of overall water productivity of the system (including ?green? and ?blue water? consumption). A consistent combination of water productivity and water scarcity footprint metrics provides a complete picture both in terms of potential productivity improvements of the water consumption as well as minimizing potential environmental impacts related to water scarcity. This process resulted for the first time in an international consensus on water use assessment, including both the life-cycle assessment community with the water scarcity footprint and the water management community with water productivity metrics. Despite the main focus on feed and livestock production systems, the outcomes of this LEAP TAG are also applicable to many other agriculture sectors

    Water quality in agriculture: Risks and risk mitigation

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    Edited by: Pay Drechsel, Sara Marjani Zadeh, and Francisco Pedrero SalcedoWater quality is of paramount importance for human lives, food production, and nature, and of concern where agricultural pollution, salinization, or lack of adequate wastewater treatment transform water from a resource into a potential hazard. This is in particular the case in many low- and middle-income countries water treatment is not keeping pace with population growth and urbanization resulting in about 30 million hectares of agricultural land, home to over 800 million residents, irrigated with polluted water. In addition to irrigated crop production, animal husbandry and aquaculture may be greatly affected by poor water quality, and can also contribute significantly to water quality degradation. These challenges prompted the Food and Agriculture Organization of the United Nations (FAO) to publish in 1976 a benchmark publication entitled Water Quality for Agriculture, followed in 1992 by Wastewater Treatment and Use in Agriculture. Over the ensuing 30 years, water quality challenges have grown resulting in a plethora of new research on water pollution, risk assessments and risk mitigation, as well as various sets of new water reuse guidelines. Based on this premise, FAO, in partnership with the International Water Management Institute (IWMI), began production of a review of current water quality guidelines, resulting in this one-volume handbook for evaluating the suitability of water for crop irrigation, livestock and fish production. The publication emphasizes good agricultural practices, including risk mitigation measures suitable for the contexts of differently resourced countries and institutions. With a focus on the sustainability of the overall system, it also covers possible downstream impacts of farm-level decisions. Water Quality in Agriculture: Risks and Risk Mitigation is intended for use by farm and project managers, extension officers, consultants and engineers to evaluate water quality data and identify potential problems and solutions related to water quality, but will also be of value to the scientific research community and studentsThis work started in 2020 under the CGIAR Research Programme on Water, Land and Ecosystems (WLE), and was further supported by the CGIAR initiative on “Resilient Cities through Sustainable Urban and Peri-urban Agrifood Systems” and the CGIAR Fund DonorsPeer reviewe

    Myosin heavy chain isoforms, fatty acid composition, sensory evaluation and quality of cinta senese pig meat

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    The aims of this study were to examine the effects of myosin heavy chain (MHC) isoforms on Cinta Senese meat and sensory quality. The research was carried out on 65 pigs and muscle samples characteristics such as MHC isoform, meat quality, fatty acid composition, and sensory were evaluated. The results demonstrated that MHC slow isoform content was significantly correlated with pH24h (r=0.25, P<0.05) and drip loss (r=-0.31, P<0.005), whereas the content of MHC isoforms was only weakly correlated with fatty acids. Sensory evaluation was done by a trained panel test and the results shown that the MHC fast/slow ratio was correlated with the juiciness (r=-0.32, P<0.005), off-flavor (r=0.33, P<0.01), and tenderness attributes (r=-0.42 to -0.46). We therefore conclude that the content of MHC isoforms can be one of the most important factors for examination of overall quality of Cinta Senese pigs
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