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1.
Sci Total Environ ; 612: 590-604, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28865275

RESUMO

Peri-urbanisation is the expansion of compact urban areas towards low-density settlements. This phenomenon directly challenges the agricultural landscape multifunctionality, including its carbon (C) storage capacity. Using satellite data, we mapped peri-urban C stocks in soil and built-up surfaces over three areas from 1993 to 2014 in the Emilia-Romagna region, Italy: a thinly populated area around Piacenza, an intermediate-density area covering the Reggio Emilia-Modena conurbation and a densely anthropized area developing along the coast of Rimini. Satellite-derived maps enabled the quantitative analysis of spatial and temporal features of urban growth and soil sealing, expressed as the ratio between C in built-up land and organic C in soils (Cc/Co). The three areas show substantial differences in C stock balance and soil sealing evolution. In Piacenza (Cc/Co=0.07 in 1993), although questioned by late industrial expansion and connected residential sprawl (Cc/Co growth by 38%), most of the new urbanisation spared the best rural soils. The Reggio Emilia-Modena conurbation, driven by the polycentricism of the area and the heterogeneity of economic sectors (Cc/Co rising from 0.08 to 0.14 from 1993 to 2014), balances sprawl and densification. Rimini, severely sealed since the 1960s (Cc/Co=0.23 in 1993), densifies its existing settlements and develops an industrial expansion of the hinterland, with Cc/Co growth accelerating from +15% before 2003 to +36% for the last decade.

2.
Environ Sci Technol ; 45(12): 5112-7, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21609007

RESUMO

Changes in land use/cover that are commonly associated with urbanization can dramatically influence the amount, chemical form, and spatial distribution of carbon (C) stocks. Measured values and relative literature for composition of natural and anthropogenic materials have been compiled. These data are used in conjunction with land cover statistics and expert assessment of building design to calculate C stocks associated with 150 years of land use change and development for an area of the Po River Valley, Northern Italy. Using 4 time periods (1853, 1954, 1976, and 2003), we demonstrate that the C stocks within this densely populated area have undergone considerable modification. A 52% increase in population density has been associated with an increase in the proportion of total C stored in anthropogenic stocks from 0.2% to 6%; this has been accompanied by a one order of magnitude increase in the carbon emission per capita per unit area. These changes have also been accompanied by a major shift in stocks from organic to inorganic forms of C.


Assuntos
Carbono/análise , Conservação dos Recursos Naturais , Atividades Humanas , Dióxido de Carbono/análise , Humanos , Itália , Minerais/química , Compostos Orgânicos/análise , Solo/química
3.
J Biomed Mater Res B Appl Biomater ; 76(1): 15-25, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16206255

RESUMO

Clinical research has long been testing techniques of integrating biomaterials with many external factors, such as simple proteins or more complicated devices, in order to achieve the restitutio ad integrum of periodontium. This study assessed the in vitro effectiveness of platelet derivate growth factor-BB (PDGF) and insulin growth factor I (IGF); the biocompatibility of materials like Paroguide, Oclastim membranes, Gingistat sponges, Surgiplaster, and Capset; and their efficacy as carriers for the platelet derivate growth factor-BB (PDGF) and insulin growth factor I (IGF). Fibroblasts from the human periodontal ligament were incubated with growth factors free or vehiculated. Mitogenic effect was evaluated by measuring the growth rate and biocompatibility by observing cell morphology at SEM. PDGF was the most effective in stimulating cell proliferation both in solution (p < 0.001) and vehiculated (p < 0.01). Surgiplaster and Capset were more biocompatible; however, final analysis to assess their efficacy as carriers failed to disclose significant differences between experimental findings and control.


Assuntos
Materiais Biocompatíveis , Gengiva/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Mitógenos/farmacologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Adolescente , Adulto , Fibroblastos/efeitos dos fármacos , Fibroblastos/ultraestrutura , Gengiva/crescimento & desenvolvimento , Gengiva/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura
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