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1.
Environ Manage ; 66(6): 1039-1058, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33150484

RESUMO

The subarctic Teno River is one of the most significant spawning rivers for Atlantic salmon in Europe. In 2009, research indicated that the Teno salmon stock was in a weak state, and concern about the future of Atlantic salmon in the Teno River arose on both sides of the river, in Finland and Norway. In 2017, the governments ratified the new Teno fishing agreement (Teno Fishing Act 2017). The agreement aimed to reduce the fishing volume by 30%, and the new regulations concerned all users, including the indigenous Sámi, other locals, tourists, and fishing entrepreneurs. This triggered concern and anger in the Sámi community and among other locals generally. The dispute raised a question concerning the management of Teno salmon. We conducted a Q inquiry with 43 statements, covering aspects of interest, knowledge, management, and policy needs related to Teno salmon. We hypothesised that the key reason for the management tensions lay in how scientific and traditional knowledge fitted administrative knowledge requirements. By using self-organising maps (SOMs), four webs of beliefs emerged from the data: traditional Sámi fishing; salmon protection; equal economic opportunity; and evidence-based decision-making. We also further analysed the statements according to how they reproduced diverging and similar beliefs. We discuss the identity-related struggle, rights, and stakes and the underlying issue of confidence and respect.


Assuntos
Salmo salar , Animais , Europa (Continente) , Finlândia , Humanos , Grupos Populacionais , Rios
2.
J Environ Manage ; 92(6): 1550-63, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21288630

RESUMO

Controversy between alternative uses of forests in Finnish Upper Lapland has been going on for decades, and in recent years it has been escalated to a serious conflict. The core of the conflict is the adverse impacts of forestry on old forests which are important grazing areas for reindeer and which are regarded as intact nature and wilderness areas. This paper describes the experiences of applying multi-criteria decision analysis interview approach on this conflict. The approach provides tools for structuring the problem and preferences of the stakeholders as well as for analyzing the effects of different alternatives in a common framework. We focus on the practical experiences gained from the application of this approach in this context. Multi-criteria decision analysis was found to be a useful approach to evaluate the economic, ecological and cultural aspects of this intense conflict. The obtained experiences also support the view that the approach works best when tightly integrated into the planning process.


Assuntos
Criação de Animais Domésticos/métodos , Conservação dos Recursos Naturais/métodos , Sistemas de Apoio a Decisões Administrativas , Agricultura Florestal/métodos , Rena/fisiologia , Animais , Finlândia , Negociação
3.
Dent Mater ; 23(7): 878-84, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16949660

RESUMO

OBJECTIVES: This study was aimed to determine if short-term water storage would change elastic properties of dental composite materials. METHODS: Particulate filler composite resin and continuous unidirectional E-glass FRC materials were photopolymerized and additionally post-polymerized by heat for testing elastic properties with the Resonance Ultrasound Spectroscopy method as a function of time in water storage. The test specimens were stored in 37 degrees C water for up to 30 days. RESULTS: About 1% weight increase due to water sorption was observed in both materials with both polymerization methods. Water sorption did not change the resonance frequencies towards lower values, indicating no significant decrease in elastic properties in these materials. Because of high damping of the polymer composite materials leading to wide resonance peaks and low number of the recorded peaks, accurate determination of the elastic properties was not possible. SIGNIFICANCE: Results suggest that the most likely explanation for the previously observed decrease in bending stiffness of FRC materials is the decreased yield limit of the hydrated polymer matrix. It is important to recognize that water sorption has the effect on mechanical properties of dental composite materials by changing the yield limit of the matrix rather than by changing the elastic properties of the material.


Assuntos
Resinas Compostas , Absorção , Restauração Dentária Permanente , Análise do Estresse Dentário , Armazenamento de Medicamentos , Elasticidade , Vidro , Transição de Fase , Maleabilidade , Análise Espectral/métodos , Ultrassonografia/métodos , Água
4.
J Prosthet Dent ; 94(3): 219-26, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16126074

RESUMO

STATEMENT OF PROBLEM: Many current fabrication protocols for dental fiber-reinforced composites use hand lay-up techniques and technician design input. Little information exists regarding how the manipulation of the cross-sectional design of a prosthesis might affect the modulus of elasticity and toughness. PURPOSE: The aim of this study was to determine the effect of simple and complex cross-sectional designs on the modulus of elasticity and toughness of fiber-reinforced composite used for dental prostheses. MATERIAL AND METHODS: Two particulate composites (BelleGlass HP and Targis) were reinforced with ultra-high-molecular-weight polyethylene fiber ribbon (Connect), woven E-glass fibers (Vectris Frame), or unidirectional R-glass fibers (Vectris Pontic). A range of fiber positions, orientations, or geometries were incorporated into the rhombic specimens (2 x 2 x 25 mm(3)) to achieve simple and complex experimental cross-sectional designs. The control specimen did not contain fiber reinforcement. Specimens (n=6) were stored 1 week in distilled water at 37 degrees C prior to 3-point load testing to determine the modulus of elasticity (GPa) and toughness (MPa). The data within each main fiber group were subjected to 1-way analysis of variance and a Tukey post hoc test (alpha=.05). Cross-sections of randomly selected test specimens (n=2) were made for scanning electron microscope (SEM) analysis of the fiber distribution. RESULTS: The mean modulus of elasticity varied from 8.7 +/- 2.0 GPa (Targis control) to 21.6 +/- 1.4 GPa (2 unidirectional glass fiber reinforcements, 1 each at the tension side and the compression side). Mean toughness varied from 0.07 +/- 0.02 MPa (unidirectional glass fiber positioned at the compression side) as the lowest mean, to 4.53 +/- 0.89 MPa (unidirectional glass fiber positioned at the tension side) as the highest. Significant differences were identified between specimen groups in each main category (all groups P<.001, except modulus of elasticity of the woven E-glass groups, where P=.003). SEM micrographs showed fiber distribution in the cross section of test specimens to correspond with the intended fiber geometry. CONCLUSION: The modulus of elasticity of the composite specimens increased when 1 or more glass fiber groups were located at the compression side of the specimen. Toughness was most effectively increased when 1 or more fiber groups were located at the tension side of the specimen.


Assuntos
Resinas Compostas/química , Análise de Variância , Força Compressiva , Análise do Estresse Dentário , Elasticidade , Vidro , Cimentos de Ionômeros de Vidro , Teste de Materiais , Metacrilatos , Microscopia Eletrônica de Varredura , Polietilenos , Cimento de Silicato , Resistência à Tração
5.
Dent Mater ; 20(10): 947-55, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15501323

RESUMO

OBJECTIVES: The aim of this study was to determine the effect of fiber position and orientation on the initial and final fracture loads of fiber-reinforced composite (FRC). METHODS: Test specimens made of two indirect particulate composites (BelleGlass HP, Kerr, Orange, CA) or (Targis, Ivoclar Vivadent, Amherst, NY) were reinforced with ultra high molecular weight polyethylene (UHMWPE) fiber ribbon (Connect, Kerr, Orange, CA), woven E-glass fibers (Vectris Frame, Ivoclar Vivadent, Amherst, NY) or unidirectional R-glass fibers (Vectris Pontic, Ivoclar Vivadent, Amherst, NY). Fibers were placed with different positions, orientations or geometry into the rhombic test specimens (2 x 2 x 25 mm3). Control specimens did not contain fiber reinforcement. The test specimens (n=6) were stored in distilled water for 1 week at 37 degrees C before testing in a three-point loading test to determine the initial and final fracture load values. RESULTS: Initial failure loads varied from 22.6 to 172.1 N. The lowest value resulted from one UHMWPE reinforcement fiber located in diagonal orientation and the highest from two unidirectional glass fiber reinforcements, one located on the tension side and the second on the compression side. SIGNIFICANCE: Position and fiber orientation influenced the load to initial and final failure, and specimen deflection. Tension side reinforcement was most effective in increasing the load to initial and final fracture.


Assuntos
Resinas Compostas/química , Metacrilatos/química , Análise de Variância , Falha de Restauração Dentária , Análise do Estresse Dentário/métodos , Análise de Falha de Equipamento , Vidro , Cimentos de Ionômeros de Vidro , Teste de Materiais , Polietilenos , Cimento de Silicato , Estatísticas não Paramétricas , Resistência à Tração
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