1,309 research outputs found

    Self-adjoint elliptic operators with boundary conditions on not closed hypersurfaces

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    The abstract theory of self-adjoint extensions of symmetric operators is used to construct self-adjoint realizations of a second-order elliptic operator on Rn\mathbb{R}^{n} with linear boundary conditions on (a relatively open part of) a compact hypersurface. Our approach allows to obtain Krein-like resolvent formulas where the reference operator coincides with the "free" operator with domain H2(Rn)H^{2}(\mathbb{R}^{n}); this provides an useful tool for the scattering problem from a hypersurface. Concrete examples of this construction are developed in connection with the standard boundary conditions, Dirichlet, Neumann, Robin, δ\delta and δ\delta^{\prime}-type, assigned either on a n1n-1 dimensional compact boundary Γ=Ω\Gamma=\partial\Omega or on a relatively open part ΣΓ\Sigma\subset\Gamma. Schatten-von Neumann estimates for the difference of the powers of resolvents of the free and the perturbed operators are also proven; these give existence and completeness of the wave operators of the associated scattering systems.Comment: Final revised version, to appear in Journal of Differential Equation

    Consumer attitudes towards sustainability attributes on food labels

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    With current concerns about climate change and the general status of the environment, there is an increasing expectation that products have sustainability credentials, and that these can be verified. Labelling is a common method of communicating certain product attributes to consumers that may influence their choices. There are different types of labels with several functions. The aim of this study is to investigate consumers‟ purchase decisions towards certain sustainability claims on food products, particularly by displaying the reduction of carbon emissions. Choice outcomes will be evaluated using Discrete Choice Modelling (DCM). Data for the study is obtained by a web-based consumer survey undertaken in the United Kingdom (UK). Results provide information on different attributes effects on consumers‟ purchase decisions, particularly their willingness to pay. This study provides information on consumers‟ attitudes that will assist industries and firms to benefit from market opportunities, in particular assessing the methods by which carbon footprinting measures can be incorporated alongside information on other sustainability criteria in product marketing.food labeling, carbon footprint, discrete choice modeling, Agribusiness, Agricultural and Food Policy, Consumer/Household Economics, Environmental Economics and Policy, Food Security and Poverty, Health Economics and Policy,

    Silicon, endophytes and secondary metabolites as grass defenses against mammalian herbivores

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    Article Accepted Date: 30 August 2014 Acknowledgments This study was supported by the Academy of Finland (grant no. 133495 to Otso Huitu; grants no. 137909 and 110658 to Kari Saikkonen) and by the NERC (grant no. NE/F003994/1 to Xavier Lambin). We thank Dr. Stefan Reidinger and Dr. James Stockdale for help with the silicon analyses. Technician Sinikka Sorsa conducted the phenolic extractions. Stephen Ryan and Anaïs Zimmer assisted with field work.Peer reviewedPublisher PD

    Consumer Attitudes towards Sustainability Attributes on Food Labels

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    Concerns about climate change and the general status of the environment have increased expectation that food products have sustainability credentials, and that these can be verified. There are significant and increasing pressures in key export markets for information on Greenhouse gas (GHG) intensity of products throughout its life-cycle. How this information is conveyed to consumers is a key issue. Labelling is a common method of communicating certain product attributes to consumers that may influence their choices. In a choice experiment concerning fruit purchase decisions, this study estimates willingness to pay for sustainability attributes by consumers in Japan and the UK. The role of label presentation format is investigated: text only, text and graphical, and graphical only. Results indicate that sustainability attributes influence consumers’ fruit purchase decisions. Reduction of carbon in fruit production is shown to be the least valued out of sustainability attributes considered. Differences are evident between presentation formats and between countries, with increased nutrient content being the most sensitive to format and country while carbon reduction is the most insensitive and almost always valued the least.Willingness to pay, Choice experiment, Food labelling, Sustainability, Cross-country comparison, Agricultural and Food Policy, Consumer/Household Economics, Environmental Economics and Policy, Food Consumption/Nutrition/Food Safety, Q18, Q51, Q56,

    Clearance of senescent hepatocytes in a neoplastic-prone microenvironment delays the emergence of hepatocellular carcinoma

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    Increasing evidence indicates that carcinogenesis is dependent on the tissue context in which it occurs, implying that the latter can be a target for preventive or therapeutic strategies. We tested the possibility that re-normalizing a senescent, neoplastic-prone tissue microenvironment would exert a modulatory effect on the emergence of neoplastic disease. Rats were exposed to a protocol for the induction of hepatocellular carcinoma (HCC). Using an orthotopic and syngeneic system for cell transplantation, one group of animal was then delivered 8 million normal hepatocytes, via the portal circulation. Hepatocytes transplantation resulted in a prominent decrease in the incidence of both pre-neoplastic and neoplastic lesions. At the end of 1 year 50% of control animals presented with HCC, while no HCC were observed in the transplanted group. Extensive hepatocyte senescence was induced by the carcinogenic protocol in the host liver; however, senescent cells were largely cleared following infusion of normal hepatocytes. Furthermore, levels of Il-6 increased in rats exposed to the carcinogenic protocol, while they returned to near control values in the group receiving hepatocyte transplantation. These results support the concept that strategies aimed at normalizing a neoplastic-prone tissue landscape can modulate progression of neoplastic disease

    Consumer attitudes towards sustainability attributes on food labels

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    Concerns about climate change and the general status of the environment have increased expectation that food products have sustainability credentials, and that these can be verified. There are significant and increasing pressures in key export markets for information on Greenhouse gas (GHG) intensity of products throughout its life-cycle. How this information is conveyed to consumers is a key issue. Labelling is a common method of communicating certain product attributes to consumers that may influence their choices. In a choice experiment concerning fruit purchase decisions, this study estimates willingness to pay for sustainability attributes by consumers in Japan and the UK. The role of label presentation format is investigated: text only, text and graphical, and graphical only. Results indicate that sustainability attributes influence consumers’ fruit purchase decisions. Reduction of carbon in fruit production is shown to be the least valued out of sustainability attributes considered. Differences are evident between presentation formats and between countries, with increased nutrient content being the most sensitive to format and country while carbon reduction is the most insensitive and almost always valued the least

    Spontaneous immunogenicity of ribosomal P0 protein in patients with benign and malignant breast lesions and delay of mammary tumor growth in P0-vaccinated mice

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    A common carboxyl-terminal epitope (C-22 P0) of the ribosomal P proteins (P0, P1 and P2) was shown to elicit autoantibodies in systemic lupus erythematosus (SLE) and in head and neck cancer patients. In this report we provide evidence for the in vivo immunogenicity of the P0 protein in breast cancer patients. Using recombinant P proteins, we demonstrated that sera from breast carcinoma patients (8/75) displayed significant reactivity to P0 protein when compared with healthy donor sera (0/45). Four out of the eight sera showed simultaneous reactivity to all P proteins. Breast benign tumor (3/17) and mammary hyperplasia (3/17) patient sera also showed significant reactivity to P proteins, thus suggesting that the occurrence of P protein autoantibodies might reveal mammary cell cycle dysregulation. Patient sera reacting with all P proteins recognized C-22 P0. Anti-P0 autoantibodies did not correlate with prognostic parameters of breast carcinomas. High level expression of C-22 P0 was found in mammary carcinomas compared with normal adjacent epithelium and benign lesions. To determine the antitumor activity of P0 as an immunogen, BALB-neuT transgenic mice displaying age-related breast cancer progression were vaccinated using xenogeneic P0 at the stage of mammary atypical hyperplasia. P0 vaccination significantly delayed the onset of mouse mammary tumors that overexpressed C-22 P0. Sera from P0 vaccinated mice recognized C-22 P0. Evidence for immunity to the P0 protein, its overexpression in carcinomas and its peculiar surface localization on cancer cells, along with its antitumor activity as an immunogen might be relevant for the use of P0 protein in monitoring cancer progression and in planning immunotherapeutic strategies

    Labelling sustainability - what consumers want, know and understand

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    With today’s concerns about the general status of the environment, there is an increasing expectation for products to have sustainability attributes. Labelling is a common method of letting consumers know more about what they have bought. Different consumers react differently towards various attributes on food labels and this may have an effect on their choices. It is helpful to understand which of the many attributes appeal to consumers and how much they may be willing to pay

    Effects of vessel traffic on relative abundance and behaviour of cetaceans : the case of the bottlenose dolphins in the Archipelago de La Maddalena, north-western Mediterranean sea

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    Acknowledgements This study was part of the Tursiops Project of the Dolphin Research Centre of Caprera, La Maddalena. Financial and logistical support was provided by the Centro Turistico Studentesco (CTS) and by the National Park of the Archipelago de La Maddalena. We thank the Natural Reserve of Bocche di Bonifacio for the support provided during data collection. The authors thank the numerous volunteers of the Caprera Dolphin Research Centre and especially Marco Ferraro, Mirko Ugo, Angela Pira and Maurizio Piras whose assistance during field observation and skills as a boat driver were invaluable.Peer reviewedPostprin

    A REFLECTION ON THE PROBLEMS OF EVALUATING THE COEXISTENCE BALANCE BETWEEN SHORT AND LONG CHAIN IN THE AGRI-FOOD MARKET: SOME IMPACT INDICATORS

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    The contribution made by this article is fundamentally to stimulate international debate on a subject that is not discussed sufficiently, or at least not in the terms indicated here, namely not the debate on the short or long chain efficiency and on the relative convenience of each, but the debate on how to establish research to identify what, in different contexts and globally, may be an excellent balance between short and long chain. How they can best divide the market shares up between them, considering the fact that all possible changes to this “balance of coexistence” on a sub-system level of the local market has an effect some distance away on the global system of markets. This research highlights the complex problems of assessing the optimal coexistence balance (in social wellbeing terms) of long chain and short chain in the food product market on a local and global territorial scale; the evaluation route of a hypothesised procedure to assess this coexistence ratio; the need of constructing suitable food market simulation models designed specifically to identify the above mentioned optimal coexistence balance; the difficulties of constructing these models and the present state of art on market simulation models; the analysis of the environmental, economic, and social impacts of short chain versus long chain in there many facets and related indicators and subindicators to evaluate them within simulation models; the interpretative capacity of these tangible and intagible indicators and the various modes (quantitative, proxy, qualitative data) through which they can measure/assess impacts
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