Existe, atualmente, um número significativo de pesquisas sobre o empreendedorismo feminino. No conjunto, esses estudos exploram aspectos ligados ao perfil geral e gerencial das mulheres. A análise da criação de empresas por mulheres é abordada nessas pesquisas, porém de maneira superficial, pois o enfoque principal, em geral, recai sobre o perfil delas ou de suas empresas. Quando se procura entender a criação de empresas e suas implicações, envolvendo os motivos e outros fatores que contribuíram para a decisão de iniciar a empresa, tais como a forma e obtenção de recursos, não há muitas informações disponíveis. Considerando o impacto deste processo no rumo da organização, o propósito deste estudo é o de investigar o processo de criação de empresas por mulheres, em diferentes localidades. Trata-se de uma pesquisa exploratória, realizada com mulheres empreendedoras no Brasil, Canadá e França. Em cada localidade, foram selecionadas 30 mulheres que iniciaram suas empresas, num total de 90 empreendedoras. Nos resultados, discute-se o processo de criação de empresas, a partir das razões para iniciar os negócios, os fatores antecedentes à empresa e, finalmente, sobre as formas de criação, ou seja, as origens do capital inicial e constituição jurídica. A razão predominante para criar a empresa foi a realização pessoal, seguida da visão de oportunidade de mercado e insatisfação no emprego. Predominou um tempo prévio de experiência profissional de 9 anos, em média, e a existência de pais como modelos de empreendedores para 41% dos casos. A sociedade foi a forma predominante e a origem do capital inicial foi proveniente de economias pessoais, com exceção das empresas da França que fizeram parte do estudo.

Abstract. We have investigated the extent of iron oxyhydroxide deposition on the roots of two common freshwater species, Vallisneria americana Michx. and Heteranthera dubia (Jacq.) MacM., collected from different sites in the St. Lawrence River, Qutbec, Canada, and have related metal concentrations in the root plaques both to the geochemical conditions prevailing in the host sediments (PH. metal partitioning) and to the metal concentrations within the plant root tissue. Possible effects of root plaque on sediment geochemistry are also discussed.At those sites where the two submerged plants co-existed, the amounts of Fe deposited on their respective root surfaces were positively correlated, indicating that sediment geochemistry (pH, concentration of labile metal) exerted a mote important influence on plaque formation than did inter-species differences (root physiology, morphology). Iron and Mn concentrations in the root plaque were positively correlated with each other, and with the readily extractable fractions (Fl, F2) of these metals in the adjacent sediments. In contrast, Zn concentrations in the root plaque of V. americana were not related to Zn concentrations in the sediments -the dominant geochemical process at the root surface is Fe deposition, such that the quantities of Zn deposited on the roots ate determined not by Zn geochemistry per se but rather by the amount of Fe deposition. Indeed the Zn/Pe ratios in the root plaque were related to the Zn/Fe ratios in the surrounding sediments (NHzOHmHCl extract).On a concentration basis @g/g), more Fe, Mn and Zn was found outside the root, in the iron plaque, than inside the root tissues. For all 3 metals, significant relationships were observed between the metal concentrations in the plaque and those inside the roots. For Zn, however, the best statistical relationship was not with [Zn],i,,, , but rather with the [Zn]l[Fe] ratio in the plaque. It is hypothesized that the Zn/Pe ratio in the root plaque reflects the free Zn*+ concentration adjacent to the root surface, and that this in turn affects Zn uptake by the plant root. For a given value of Zn in the sediments or in the root plaque, the Zn content of the root is inversely related to the concentration of Fe oxyhydroxides, implying that Fe plays a protective role in regulating Zn bioavailability.

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Phragmites australis (the common reed) was collected at six sites in southern Qu6bec and Ontario, Canada, in order to study the accumulation of iron plaque on the roots. The deposition of iron oxides on roots of P. australis did not correlate directly with soil measurements; however, the amounts of iron-bound-tocarbonates fraction of the soil/sediment, responsible for the iron plaque accumulation, correlated with the % of water, % of organic matter, % of clay and pH of the substrate. Plants located very near flowing water accumulated more iron plaque on the roots than plants in other habitats through the summer; it is hypothesized that carbonates associated with iron come from the flowing water. In wetlands or sites near flowing water, most root iron was found on the surface, as iron plaque, while there was more iron inside the root in dry environments. Radial oxygen loss from the roots is probably the most important source of oxygen for the oxidation of iron.