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1.
Materials (Basel) ; 11(3)2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29495571

RESUMO

An innovative recycling process for thermoset polymer composites developed by Connora Technologies (Hayward, CA, USA) was studied. The process efficacy has already been tested, and it is currently working at the plant level. The main aspect investigated in the present paper was the environmental impact by means of the Life Cycle Assessment (LCA) method. Because of the need to recycle and recover materials at their end of life, the Connora process creates a great innovation in the market of epoxy composites, as they are notoriously not recyclable. Connora Technologies developed a relatively gentle chemical recycling process that induces the conversion of thermosets into thermoplastics. The LCA demonstrated that low environmental burdens are associated with the process itself and, furthermore, impacts are avoided due to the recovery of the epoxy-composite constituents (fibres and matrix). A carbon fibre (CF) epoxy-composite panel was produced through Vacuum Resin Transfer Moulding (VRTM) and afterwards treated using the Connora recycling process. The LCA results of both the production and the recycling phases are reported.

2.
Mov Disord ; 28(4): 529-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23239509

RESUMO

BACKGROUND: Pancreatic polypeptide is released immediately after food ingestion. The release is operated by vagal-abdominal projections and has therefore been suggested as a test for vagal nerve integrity. Pathoanatomical and clinical studies indicate vagal dysfunction in early Parkinson's disease (PD). METHODS: We assessed the postprandial secretion of pancreatic polypeptide and motilin in healthy controls (n = 18) and patients with idiopathic rapid-eye-movement sleep behavior disorder (iRBD, n = 10), a potential premotor stage of PD, as well as in drug-naive (n = 19) and treated (n = 19) PD patients. RESULTS: The postprandial pancreatic polypeptide secretion showed a physiological pattern in all groups and even an enhanced response in drug-naive PD and iRBD. Motilin concentrations correlated with pancreatic polypeptide concentrations. CONCLUSIONS: Postprandial pancreatic polypeptide secretion is not a suitable test for vagal nerve integrity in PD. The unimpaired pancreatic polypeptide response in iRBD and PD might be explained by partially intact vagal-abdominal projections or compensatory mechanisms substituting a defective neuronal brain-gut axis.


Assuntos
Polipeptídeo Pancreático/biossíntese , Doença de Parkinson/metabolismo , Transtorno do Comportamento do Sono REM/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motilina/biossíntese , Doença de Parkinson/fisiopatologia , Período Pós-Prandial/fisiologia , Transtorno do Comportamento do Sono REM/fisiopatologia
3.
Waste Manag Res ; 25(3): 263-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17612327

RESUMO

A large number of methods and approaches that can be used for supporting waste management decisions at different levels in society have been developed. In this paper an overview of methods is provided and preliminary guidelines for the choice of methods are presented. The methods introduced include: Environmental Impact Assessment, Strategic Environmental Assessment, Life Cycle Assessment, Cost-Benefit Analysis, Cost-effectiveness Analysis, Life-cycle Costing, Risk Assessment, Material Flow Accounting, Substance Flow Analysis, Energy Analysis, Exergy Analysis, Entropy Analysis, Environmental Management Systems, and Environmental Auditing. The characteristics used are the types of impacts included, the objects under study and whether the method is procedural or analytical. The different methods can be described as systems analysis methods. Waste management systems thinking is receiving increasing attention. This is, for example, evidenced by the suggested thematic strategy on waste by the European Commission where life-cycle analysis and life-cycle thinking get prominent positions. Indeed, life-cycle analyses have been shown to provide policy-relevant and consistent results. However, it is also clear that the studies will always be open to criticism since they are simplifications of reality and include uncertainties. This is something all systems analysis methods have in common. Assumptions can be challenged and it may be difficult to generalize from case studies to policies. This suggests that if decisions are going to be made, they are likely to be made on a less than perfect basis.


Assuntos
Conservação dos Recursos Naturais , Técnicas de Apoio para a Decisão , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Abastecimento de Água , Saúde Ambiental , Monitoramento Ambiental , Europa (Continente) , Humanos , Modelos Econômicos , Eliminação de Resíduos/economia , Medição de Risco , Gerenciamento de Resíduos/economia
4.
Waste Manag ; 27(8): S1-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17412580

RESUMO

Treatment of solid waste continues to be on the political agenda. Waste disposal issues are often viewed from an environmental perspective, but economic and social aspects also need to be considered when deciding on waste strategies and policy instruments. The aim of this paper is to suggest flexible and robust strategies for waste management in Sweden, and to discuss different policy instruments. Emphasis is on environmental aspects, but social and economic aspects are also considered. The results show that most waste treatment methods have a role to play in a robust and flexible integrated waste management system, and that the waste hierarchy is valid as a rule of thumb from an environmental perspective. A review of social aspects shows that there is a general willingness among people to source separate wastes. A package of policy instruments can include landfill tax, an incineration tax which is differentiated with respect to the content of fossil fuels and a weight based incineration tax, as well as support to the use of biogas and recycled materials.


Assuntos
Meio Ambiente , Gerenciamento de Resíduos , Atitude , Economia , Geografia , Humanos , Suécia , Impostos , Gerenciamento de Resíduos/economia
5.
Waste Manag ; 27(8): 1046-58, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17419045

RESUMO

At the core of EU and Swedish waste policy is the so-called waste hierarchy, according to which waste should first be prevented, but should otherwise be treated in the following order of prioritisation: reuse, recycling when environmentally motivated, energy recovery, and last landfilling. Some recent policy decisions in Sweden aim to influence waste management in the direction of the waste hierarchy. In 2001 a governmental commission assessed the economic and environmental impacts of introducing a weight-based tax on waste incineration, the purpose of which would be to encourage waste reduction and increase materials recycling and biological treatment. This paper presents the results of a life cycle assessment (LCA) of the waste incineration tax proposal. It was done in the context of a larger research project concerning the development and testing of a framework for Strategic Environmental Assessment (SEA). The aim of this paper is to assess the life cycle environmental impacts of the waste incineration tax proposal, and to investigate whether there are any possibilities of more optimal design of such a tax. The proposed design of the waste incineration tax results in increased recycling, but only in small environmental improvements. A more elaborate tax design is suggested, in which the tax level would partly be related to the fossil carbon content of the waste.


Assuntos
Meio Ambiente , Incineração/economia , Modelos Teóricos , Impostos , Poluição do Ar/prevenção & controle , Conservação dos Recursos Naturais , Eutrofização , Governo Federal , Efeito Estufa , Ozônio , Política Pública , Suécia , Poluentes Químicos da Água/toxicidade
6.
Waste Manag ; 27(8): 989-96, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17434726

RESUMO

In assessments of the environmental impacts of waste management, life-cycle assessment (LCA) helps expanding the perspective beyond the waste management system. This is important, since the indirect environmental impacts caused by surrounding systems, such as energy and material production, often override the direct impacts of the waste management system itself. However, the applicability of LCA for waste management planning and policy-making is restricted by certain limitations, some of which are characteristics inherent to LCA methodology as such, and some of which are relevant specifically in the context of waste management. Several of them are relevant also for other types of systems analysis. We have identified and discussed such characteristics with regard to how they may restrict the applicability of LCA in the context of waste management. Efforts to improve LCA with regard to these aspects are also described. We also identify what other tools are available for investigating issues that cannot be adequately dealt with by traditional LCA models, and discuss whether LCA methodology should be expanded rather than complemented by other tools to increase its scope and applicability.


Assuntos
Meio Ambiente , Gerenciamento de Resíduos , Poluentes Ambientais
7.
Langmuir ; 22(5): 2227-34, 2006 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-16489811

RESUMO

Adsorption of the amelogein protein mixture enamel matrix derivate (EMD) to silica surfaces has been studied by in situ ellipsometry and quartz crystal microbalance with dissipation (QCM-D). The protein was found to adsorb as nanospheres in mono- or multilayers, depending on the concentration of "free" nanospheres available in solution. The concentration of free nanospheres is determined by the competitive processes of adsorption and rapid aggregation into microscopic particles, measured by dynamic light scattering (DLS). Multilayers could also be formed by sequential injections of fresh EMD solution. At higher temperature, an up to 6 times thicker gel-like film was formed on the substrate surface, and decreasing the pH lead to disruption of the multilayer/aggregate formation and a decreased amount adsorbed.


Assuntos
Proteínas do Esmalte Dentário/química , Adsorção , Amelogenina/química , Animais , Materiais Revestidos Biocompatíveis , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Complexos Multiproteicos , Dióxido de Silício , Ressonância de Plasmônio de Superfície , Propriedades de Superfície , Suínos , Temperatura
8.
Occup Ther Health Care ; 20(2): 31-49, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-23926912

RESUMO

Stroke is one of the most disabling conditions affecting adults today. Much research has been performed on rehabilitation interventions targeting hemiparesis after stroke. Constraint-induced therapy is a treatment technique that focuses on restraining the unaffected upper extremity while forcing use of the affected extremity to promote purposeful movement. This study presents a meta-analysis of applicable current literature on this treatment approach. It is concluded that constraint-induced therapy may be an effective treatment option for hemiparesis experienced after stroke.

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