353 research outputs found

    Consumer willingness to pay for genetically modified vegetable oil and salmon in the United States and Norway

    Get PDF
    Consumer resistance against GM crops is still substantial in the United States and Europe. We conducted an internet survey in the United States and Norway with more than 1,000 respondents in each country to estimate consumers' willingness to pay (WTP) for GM soybean oil, farmed salmon fed with GM soy, and GM salmon. The differences in WTP for the conventional as compared with the GM alternatives are relatively small. Only between 7 and 13% of the respondents indicated that they were willing to pay more than a 20% premium for each of the conventional alternatives as compared to the corresponding GM alternatives. The average WTP premiums range from 7.5 to 9.2%. This suggests a large similarity in WTP in Norway and the United States and across the three products

    How to define (net) zero greenhouse gas emissions buildings: The results of an international survey as part of IEA EBC annex 72

    Get PDF
    The concept of (net) zero greenhouse gas (GHG) emission(s) buildings is gaining wide international attention and is considered to be the main pathway for achieving climate neutrality targets in the built environment. However, there is an increasing plethora of differing terms, definitions, and approaches emerging worldwide. To understand the current progress of the ongoing discussion, this study provides an overview of terms, definitions, and key features from a review of 35 building assessment approaches. The investigation identified that 13 voluntary frameworks from 11 countries are particularly characterised by net zero-carbon/GHG emissions performance targets, which are then subject to a more detailed analysis. The review was organised in the context of the project IEA EBC Annex 72 on “Assessing Life Cycle Related Environmental Impacts Caused by Buildings”, which involves researchers from over 25 countries worldwide. In the current dynamic political surroundings and ongoing scientific debate, only an initial overview of this topic can be presented. However, providing typologies and fostering transparency would be instrumental in delivering clarity, limiting misunderstanding, and avoiding potential greenwashing. To this end, this article categorises the most critical methodological options—i.e., system boundaries for both operational and embodied GHG emissions, the type of GHG emission factor for electricity use, the approach to the “time” aspect, and the possibilities of GHG emission compensation—into a comprehensive framework for clarifying or setting (net) zero GHG emission building definitions in a more systematic way. The article concludes that although variations in the existing approaches will continue to exist, certain minimum directions should be considered for the future development of harmonised (net) zero GHG emissions building frameworks. As a minimum, it is recommended to extend the usual scope of the operational energy use balance. At the same time, minimum requirements must also be set for embodied GHG emissions even if they are not considered in the carbon/GHG emissions balance

    Er Atlantisk lakseparr (Salmo salar L.) mottakelig for piscint myokardittvirus (PMCV) ved bruk av kohabitant smittemodell? En sammenligning mellom parr og smolt

    Get PDF
    CMS hos voksen laks i sjø skyldes piscint myokardittvirus (PMCV). På grunn av utbrudd rett før slakt, kan sykdommen gi store økonomiske problem. Ved forsøk med PMCV i laks, er viruset påvist flere ganger, men ved bruk av parr er det derimot ikke så mye data. Med tanke på smittemodeller ville det å kunne bruke parr i stedet for smolt, redusere vannmengde, tid og karplass. Det er derfor i samarbeid med VESO Vikan ønskelig å påvise PMCV i lakseparr, og dermed om mulig utvikle en smittemodell med PMCV i parr. I denne oppgaven ble det utført to delforsøk med kohabitantsmitte, hvor PMCV ble brukt som smitteagens. I det ene delforsøket ble det brukt 164 parr, mens i det andre ble det brukt 164 smolt. Det ble tatt vannprøver, blodprøver og uttak av organer til histologi og PCR, men det var kun histologi og PCR som ble brukt som analysemetoder. Prøveuttak ble foretatt hver uke i minst 12 uker etter smitte. En kohabitant fra smoltforsøket døde, uten påvisning av patologi. Adferden var normal, og det ble ikke notert ytre eller indre patologiske symptomer. Ved histologi ble det funnet fokale områder med betennelsesceller i atriet tidligst ved 6 uker etter smitte (wpc) hos parr shedder, og ved 8 wpc hos parr kohabitant. Hos smolt ble det funnet tidligst ved 6 wpc hos shedder, og ved 7 wpc hos kohabitant. Scoren varierte fra 0,5 – 2. Hos milt ble det ikke funnet pseudolobulering, men en del blødninger/stuvninger som ikke tydet på patologi. Det ble ikke funnet nekrose i lever, men vakuoler og fargeforandringer av hepatocytter rundt blodkar, dette ble heller ikke ansett som patologi. qPCR detekterte PMCV ved 7 wpc, 9 wpc (kun shedder) og 12 wpc hos parr, og ved 9 og 12 wpc hos smolt shedder. Det ble ikke detektert virus hos smolt kohabitant. Ct-verdiene og antall infiserte individ økte med antall uker etter smitte. Shedderne hadde lavest Ct-verdi. Av shedderne og kohabitantene var det parr som hadde flest infiserte individer. Noen individer hadde både histopatologiske tegn og påvist PMCV ved qPCR, mens noen hadde bare en av påvisningene. Etter forsøk med smittemodellen for smolt og analysemetodene histologi og qPCR, ble det påvist PMCV i lakseparr ved bruk av kohabitant smittemodell

    On tuning passive black-box macromodels of LTI systems via adaptive weighting

    Get PDF
    This paper discusses various approaches for tuning the accuracy of rational macromodels obtained via black-box identification or approximation of sampled frequency responses of some unknown Linear and Time-Invariant system. Main emphasis is on embedding into the model extraction process some information on the nominal terminations that will be connected to the model during normal operation, so that the corresponding accuracy is optimized. This goal is achieved through an optimization based on a suitably defined cost function, which embeds frequency-dependent weights that are adaptively refined during the model construction. A similar procedure is applied in a postprocessing step for enforcing model passivity. The advantages of proposed algorithm are illustrated on a few application examples related to power distribution networks in electronic system

    Ignition of thermally sensitive explosives between a contact surface and a shock

    Get PDF
    The dynamics of ignition between a contact surface and a shock wave is investigated using a one-step reaction model with Arrhenius kinetics. Both large activation energy asymptotics and high-resolution finite activation energy numerical simulations are employed. Emphasis is on comparing and contrasting the solutions with those of the ignition process between a piston and a shock, considered previously. The large activation energy asymptotic solutions are found to be qualitatively different from the piston driven shock case, in that thermal runaway first occurs ahead of the contact surface, and both forward and backward moving reaction waves emerge. These waves take the form of quasi-steady weak detonations that may later transition into strong detonation waves. For the finite activation energies considered in the numerical simulations, the results are qualitatively different to the asymptotic predictions in that no backward weak detonation wave forms, and there is only a weak dependence of the evolutionary events on the acoustic impedance of the contact surface. The above conclusions are relevant to gas phase equation of state models. However, when a large polytropic index more representative of condensed phase explosives is used, the large activation energy asymptotic and finite activation energy numerical results are found to be in quantitative agreement

    Towards Activity Context using Software Sensors

    Full text link
    Service-Oriented Computing delivers the promise of configuring and reconfiguring software systems to address user's needs in a dynamic way. Context-aware computing promises to capture the user's needs and hence the requirements they have on systems. The marriage of both can deliver ad-hoc software solutions relevant to the user in the most current fashion. However, here it is a key to gather information on the users' activity (that is what they are doing). Traditionally any context sensing was conducted with hardware sensors. However, software can also play the same role and in some situations will be more useful to sense the activity of the user. Furthermore they can make use of the fact that Service-oriented systems exchange information through standard protocols. In this paper we discuss our proposed approach to sense the activity of the user making use of software

    The Sensitivity of Massively Parallel Sequencing for Detecting Candidate Infectious Agents Associated with Human Tissue

    Get PDF
    Massively parallel sequencing technology now provides the opportunity to sample the transcriptome of a given tissue comprehensively. Transcripts at only a few copies per cell are readily detectable, allowing the discovery of low abundance viral and bacterial transcripts in human tissue samples. Here we describe an approach for mining large sequence data sets for the presence of microbial sequences. Further, we demonstrate the sensitivity of this approach by sequencing human RNA-seq libraries spiked with decreasing amounts of an RNA-virus. At a modest depth of sequencing, viral transcripts can be detected at frequencies less than 1 in 1,000,000. With current sequencing platforms approaching outputs of one billion reads per run, this is a highly sensitive method for detecting putative infectious agents associated with human tissues
    • …
    corecore