57 research outputs found
Fragmentation processes of ionized 5-fluorouracil in the gas phase and within clusters
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.
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
The value of manure - Manure as co-product in life cycle assessment
Research ArticleLivestock production is important for food security, nutrition, and landscape maintenance, but it is associated
with several environmental impacts. To assess the risk and benefits arising from livestock production, transparent
and robust indicators are required, such as those offered by life cycle assessment. A central question in
such approaches is how environmental burden is allocated to livestock products and to manure that is re-used for
agricultural production. To incentivize sustainable use of manure, it should be considered as a co-product as long
as it is not disposed of, or wasted, or applied in excess of crop nutrient needs, in which case it should be treated
as a waste. This paper proposes a theoretical approach to define nutrient requirements based on nutrient response
curves to economic and physical optima and a pragmatic approach based on crop nutrient yield adjusted for nutrient losses to atmosphere and water. Allocation of environmental burden to manure and other livestock
products is then based on the nutrient value from manure for crop production using the price of fertilizer
nutrients. We illustrate and discuss the proposed method with two case studiesinfo:eu-repo/semantics/publishedVersio
Estudos organizacionais de aprendizagem e conhecimento à luz das abordagens situada e da tecnociência
From value-added tax to a damage and value-added tax partially based on life cycle assessment: principles and feasibility
Myosin heavy chain isoforms, fatty acid composition, sensory evaluation and quality of cinta senese pig meat
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
The development of Product Environmental Footprint (PEF) Category Rules (PEFCR)
The European Commission's “Roadmap to a Resource Efficient Europe” proposes ways to increase resource productivity and to decouple economic growth from both resource use and environmental impacts, taking a life-cycle perspective. One of its objectives is to: “Establish a common methodological approach to enable Member States and the private sector to assess, display and benchmark the environmental performance of products, services and companies based on a comprehensive assessment of environmental impacts over the life-cycle ('environmental footprint')”. The European Council invited the Commission to develop supporting methodologies. The Environmental Footprint (EF), launched by the European Commission’s Joint Research Centre in close cooperation with Directorate-General for the Environment, gives specific guidance for comprehensive, robust and consistent environmental assessment of products and organisations. This is an important step forward to ensure
robust decision support for business and policy. However, for to be more relevant to the situation and problems of specific product categories more specific guidance on how to conduct the EF study is required. The guides on Product EF (PEF) and Organisation EF (OEF) provide more specific requirements that need to be defined in so called Product
Environmental Footprint Category Rules (PEFCRs). These PEFCRs are seen as crucial for EF studies aiming at business-to-business (B2B) and business-to-consumer (B2C) communication intended to be used for comparisons and comparative assertions. The role of PEFCRs are to increase the reproducibility, consistency, comparability and relevance of EF studies, but also to increase the efficiency (reduce time, efforts and costs) of EF studies by directing the focus on the most important processes and impact categories. First steps are taken by the European
Commission to develop PEFCRs through several pilot studies. These will build on: The recent development of guidelines on the development of Product Category Rules (PCRs) by the United States Environmental Protection Agency Existing PCRs and specific sector guidance such as the European Food Sustainable Consumption and Production (SCP) Round Table, PAS2050, GEDNets PCRs for Environmental Product Declaration (EPD) and the Repository of good practice in France (related to BP X 30-323) Knowledge and experience from a broad spectre of stakeholders For the development of PEFCR there are at least three major challenges that will be discussed in the presentation: definition of the Product Category/Sector in a way that allows for meaningful comparison of products fulfilling an equivalent function,
definition and modelling of an average product(s) and identifying and focussing on what matters most. This contribution gives an overview of what PEFCRs are and highlights some issues relating to their development. Keywords: Environmental Footprint (EF), Product Category Rules (PCR), Product Environmental Footprint Category
Rules (PEFCRs).status: publishe
Optimizing current control performance in double winding asynchronous motors in large power inverter drives
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