1,449 research outputs found

    An exotic smooth structure on CP^2+6CP^2-bar

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    We construct smooth 4-manifolds homeomorphic but not diffeomorphic to CP^2+6CP^2-bar.Comment: Published by Geometry and Topology at http://www.maths.warwick.ac.uk/gt/GTVol9/paper19.abs.htm

    Topological quantum D-branes and wild embeddings from exotic smooth R^4

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    This is the next step of uncovering the relation between string theory and exotic smooth R^4. Exotic smoothness of R^4 is correlated with D6 brane charges in IIA string theory. We construct wild embeddings of spheres and relate them to a class of topological quantum Dp-branes as well to KK theory. These branes emerge when there are non-trivial NS-NS H-fluxes where the topological classes are determined by wild embeddings S^2 -> S^3. Then wild embeddings of higher dimensional pp-complexes into S^n correspond to Dp-branes. These wild embeddings as constructed by using gropes are basic objects to understand exotic smoothness as well Casson handles. Next we build C*-algebras corresponding to the embeddings. Finally we consider topological quantum D-branes as those which emerge from wild embeddings in question. We construct an action for these quantum D-branes and show that the classical limit agrees with the Born-Infeld action such that flat branes = usual embeddings.Comment: 18 pages, 1 figur

    Environmental impact of a new concept of food service: A case study for the re-use of naval shipping containers

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    This study aims to evaluate the environmental sustainability of a new street food format for food service based on the re-use of naval shipping containers and to compare it with the conventional one (street food truck). The environmental impact analysis was performed using the Life Cycle Assessment methodology. The functional unit (FU) was identified in the food service, including three food preparations: a dish of pasta (100 g), one sandwich (150 g) and one portion of fries (200 g). Following a \u201cfrom cradle to gate\u201d approach, the factors studied are: (i) the customization of a shipping container in a street food format, (ii) the construction and use of the cooking appliance, (iii) the logistics, (iv) the cooking phase (including final packaging as food cup). The life cycle of ingredients for food preparations has been neglected due to the variability of the products. The results show that the two higher hotspots are electricity consumed by cooking appliance (35%) and oil used to fry (34%), attributable only to the fries preparation. The third hotspot is imputable to the customized structure, with an average percentage value equal to 15%. Considering the global warming impact category, the customization into a street food format release 1280 kg CO2eq, while the production of a new container or a new street food truck format implies the emission of 12,800 kg CO2eq and 20,900 kg CO2eq respectively. The impact of the customized container (re-used container) weight for 0.04 kg CO2eq/FU, this value increases 11.6 times for a new container street food format, and 17 times for a new street food truck format. Overall, quantifying the environmental damage, the results showed how the re-use of a naval shipping container can be a way to reduce the environmental impact of food preparation, avoiding dismissing or building activity of the structure reducing the impact of the structure of about 95% offering a more sustainable street food services

    Is There Chronic Brain Damage in Retired NFL Players? Neuroradiology, Neuropsychology, and Neurology Examinations of 45 Retired Players

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    BACKGROUND: Neuropathology and surveys of retired National Football League (NFL) players suggest that chronic brain damage is a frequent result of a career in football. There is limited information on the neurological statuses of living retired players. This study aimed to fill the gap in knowledge by conducting in-depth neurological examinations of 30- to 60-year-old retired NFL players. HYPOTHESIS: In-depth neurological examinations of 30- to 60-year-old retired players are unlikely to detect objective clinical abnormalities in the majority of subjects. STUDY DESIGN: A day-long medical examination was conducted on 45 retired NFL players, including state-of-the-art magnetic resonance imaging (MRI; susceptibility weighted imaging [SWI], diffusion tensor imaging [DTI]), comprehensive neuropsychological and neurological examinations, interviews, blood tests, and APOE (apolipoprotein E) genotyping. LEVEL OF EVIDENCE: Level 3. METHODS: Participants\u27 histories focused on neurological and depression symptoms, exposure to football, and other factors that could affect brain function. The neurological examination included Mini-Mental State Examination (MMSE) evaluation of cognitive function and a comprehensive search for signs of dysarthria, pyramidal system dysfunction, extrapyramidal system dysfunction, and cerebellar dysfunction. The Beck Depression Inventory (BDI) and Patient Health Questionnaire (PHQ) measured depression. Neuropsychological tests included pen-and-paper and ImPACT evaluation of cognitive function. Anatomical examination SWI and DTI MRI searched for brain injuries. The results were statistically analyzed for associations with markers of exposure to football and related factors, such as body mass index (BMI), ethanol use, and APOE4 status. RESULTS: The retired players\u27 ages averaged 45.6 +/- 8.9 years (range, 30-60 years), and they had 6.8 +/- 3.2 years (maximum, 14 years) of NFL play. They reported 6.9 +/- 6.2 concussions (maximum, 25) in the NFL. The majority of retired players had normal clinical mental status and central nervous system (CNS) neurological examinations. Four players (9%) had microbleeds in brain parenchyma identified in SWI, and 3 (7%) had a large cavum septum pellucidum with brain atrophy. The number of concussions/dings was associated with abnormal results in SWI and DTI. Neuropsychological testing revealed isolated impairments in 11 players (24%), but none had dementia. Nine players (20%) endorsed symptoms of moderate or severe depression on the BDI and/or met criteria for depression on PHQ; however, none had dementia, dysarthria, parkinsonism, or cerebellar dysfunction. The number of football-related concussions was associated with isolated abnormalities on the clinical neurological examination, suggesting CNS dysfunction. The APOE4 allele was present in 38% of the players, a larger number than would be expected in the general male population (23%-26%). CONCLUSION: MRI lesions and neuropsychological impairments were found in some players; however, the majority of retired NFL players had no clinical signs of chronic brain damage. CLINICAL RELEVANCE: These results need to be reconciled with the prevailing view that a career in football frequently results in chronic brain damage

    Definition of glaucoma: clinical and experimental concepts

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    Glaucoma is a term describing a group of ocular disorders with multi-factorial etiology united by a clinically characteristic intraocular pressure-associated optic neuropathy. It is not a single entity and is sometimes referred to in the plural as the glaucomas. All forms are potentially progressive and can lead to blindness. The diverse conditions that comprise glaucoma are united by a clinically characteristic optic neuropathy: glaucomatous optic neuropathy (GON). Evidence suggests that the primary site of neurological injury is at the optic nerve head. This fact enables the conditions to be grouped, irrespective of the causal mechanism(s). The term experimental glaucoma implies model resemblance to the human condition. We propose that 'experimental glaucoma' be restricted to animal models with demonstrable features of GON and/or evidence of a primary axonopathy at the optic nerve head. A fundamental inadequacy in this framework is any reference to the pathogenesis of GON, which remains unclear.Robert J Casson, Glyn Chidlow, John PM Wood, Jonathan G Crowston, and Ivan Goldber

    The E-LCA as a tool to quantify the environmental impact of meat and legumes-based burgers

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    Thanks to its high biological and nutritional values, the meat has always been considered an interesting food for a good diet. However, ethical reasons, religious restrictions and the high prices have driven the consumers\u2019 behaviours towards alternative products. Nowadays, the demand for new food formulations has an upward trend. This is also due to the growing awareness of consumers about the environmental impact of food productions. In this scenario, the legumes are considered an alternative food compared to meat. For this reason, one of the aims of the international project \u201cLegume Genetic Resources as a tool for development of innovative and sustainable food Technological system\u201d (LeGeReTe) is to evaluate the environmental sustainability of legume-based products. An Environmental-Life Cycle Assessment (E-LCA) was performed to evaluate the environmental profile of one meat burger and one legume-based burger. A conventional functional unit of \u20181 burger (100 g)\u2019 and an alternative one of \u201815 g of proteins\u2019 were used, applying for the study a \u201cfrom cradle to grave\u201d approach. The environmental impact assessment helped to identify the most impactful activities: for both the production chains, the agricultural phases were identified as the most damaging. Regarding the production processes, the legume-based burger was identified as the most energy demanding compared to the meat burger. Considering a functional unit of 1 burger, the results suggest that the meat burger is 3.44 times more impactful compared to the legume-based burger. While switching to a nutritional functional unit (15 g of proteins), the results showed that to reach the same protein content of a meat burger, is necessary to double the legume-based burger production which remains anyway the most sustainable option. In conclusion, the legume-based burger can be defined as the most environmentally-friendly solution both from a production and from a nutritional point of view

    Life cycle thinking applied to the analyses sector : a case study on olive oil analyses using E-LCA and LCC approach

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    The Life Cycle Thinking (LCT) is an approach that aims to evaluate the sustainability profile of a process, a product or a service, and takes in account all the steps involved in the life cycle. In the olive oil production chain, the activities related to the analyses of olives maturity index and of the quality parameters of the olive oils were neglected by LCT studies so far. Therefore, the aim of the work was to evaluate the sustainability of the analyses performed on olives and olive oils, comparing the chemical methods with the optical one base on visible and near infrared spectroscopy (vis/NIR). The assessment considers the different ways to perform the analyses. The chemical one consists in a destructive approach using reagents, different devices and with high energy consumption for some steps; vis/NIR does not need any sample-preparation, reagents and requires less time. The Environmental Life Cycle Assessment (E-LCA) was applied to evaluate the environmental sustainability. Moreover, the Life Cycle Cost (LCC) analysis was carried out to quantify the economic sustainability of the two method of analyses. The functional unit was defined as one analysis and for both the two methods a \u201cfrom cradle to grave\u201d approach was used identifying all the inputs (data, amount of resources or raw materials, devices or chemicals that enter in one process) and outputs (final materials and waste materials) of the chemical and optical analyses. The environmental profile comparison allows to identify that the vis/NIR analysis is sharply better, 38 times than the chemical one. Regarding the LCC evaluation, the single analysis has quite the same price and the variation is due to the chemicals and analytical tools used. Even for the LCC evaluation, the optical analysis is preferable and cheaper, showing costs 60% less compared to the chemical analysis. In conclusion, considering the E-LCA and the LCC methods, the optical analyses are more sustainable than the chemical ones. Optical analyses as vis/NIR spectroscopy can be properly defined as green technologies

    Environmental benefits : conventional vs innovative packaging for olive oil

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    In the last years, different issues as costs and lower availability of materials and resources became a driving force to increase the sustainability of agro-food activity. In this scenario, the olive oil industry is characterized by different processes that could affect the environment. Moreover, the plastic packaging used in the sector could have a relevant environmental impact referred both to the production phase and to the disposal scenario. Therefore, the aim on the work was the evaluation of the environmental impact of two different mono-use olive oil packaging. This study is part of the project \u201cSustainability of olive oil System (S.O.S.)\u201d, funded by AGER. A conventional packaging composed by polyethylene (PE), polyethylene terephthalate (PET), polyurethane (PU) and aluminium was compared to a bio-based packaging composed by biopolyethylene (Bio-PE), polylactic acid (PLA) and a thin layer of aluminium. A Life Cycle Assessment (LCA) was performed to identify the environmental profiles of the two packaging. The functional unit was defined as one mono-use packaging (10 mL volume). The study considered the environmental performance related to all the activities from the raw material extraction, through the transformation phases, till the disposal scenario. The comparison of the two packaging showed that the conventional packaging affects more in the impact category \u201cclimate change\u201d (1,5 times), \u201chuman toxicity\u201d (1,4 times) and in \u201cresource depletion\u201d where the results are 4 times higher respect to the innovative packaging due to the extraction of non-renewable raw materials. Nevertheless, higher impacts are attributable to the biobased packaging for ecosystem quality categories as \u201ceutrophication\u201d (1,2 times), \u201cfreshwater ecotoxicity\u201d (1,5 times) and \u201cacidification\u201d (1,2 times). Analysing the waste management scenario, it is not possible to identify a clear disposal procedure due to the composition of the packaging, the consumers\u2019 behaviour and the regional regulations. Therefore, in this study it was supposed the incineration of both the products. In conclusion it is not possible to confirm that the bio-based olive oil packaging is more environmentally friendly respect to the conventional one, due to the land use and to the need as well of impacting chemical processes also to produce the bio-based films

    Environmental benefits : conventional vs innovative packaging for olive oil

    Get PDF
    In the last years, different issues as costs and lower availability of materials and resources became a driving force to increase the sustainability of agro-food activity. In this scenario, the olive oil industry is characterized by different processes that could affect the environment. Moreover, the plastic packaging used in the sector could have a relevant environmental impact referred both to the production phase and to the disposal scenario. Therefore, the aim on the work was the evaluation of the environmental impact of two different mono-use olive oil packaging. This study is part of the project \u201cSustainability of olive oil System (S.O.S.)\u201d, funded by AGER. A conventional packaging composed by polyethylene (PE), polyethylene terephthalate (PET), polyurethane (PU) and aluminium was compared to a bio-based packaging composed by biopolyethylene (Bio-PE), polylactic acid (PLA) and a thin layer of aluminium. A Life Cycle Assessment (LCA) was performed to identify the environmental profiles of the two packaging. The functional unit was defined as one mono-use packaging (10 mL volume). The study considered the environmental performance related to all the activities from the raw material extraction, through the transformation phases, till the disposal scenario. The comparison of the two packaging showed that the conventional packaging affects more in the impact category \u201cclimate change\u201d (1,5 times), \u201chuman toxicity\u201d (1,4 times) and in \u201cresource depletion\u201d where the results are 4 times higher respect to the innovative packaging due to the extraction of non-renewable raw materials. Nevertheless, higher impacts are attributable to the biobased packaging for ecosystem quality categories as \u201ceutrophication\u201d (1,2 times), \u201cfreshwater ecotoxicity\u201d (1,5 times) and \u201cacidification\u201d (1,2 times). Analysing the waste management scenario, it is not possible to identify a clear disposal procedure due to the composition of the packaging, the consumers\u2019 behaviour and the regional regulations. Therefore, in this study it was supposed the incineration of both the products. In conclusion it is not possible to confirm that the bio-based olive oil packaging is more environmentally friendly respect to the conventional one, due to the land use and to the need as well of impacting chemical processes also to produce the bio-based films
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