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RESUMO O objetivo deste artigo é investigar os padrões de interação de empresas nacionais e multi... more RESUMO O objetivo deste artigo é investigar os padrões de interação de empresas nacionais e multinacionais localizadas no Brasil com universidades/institutos públicos de pesquisa (IPPs) presentes no país. Para tanto, utilizou-se uma base de dados que envolve 319 ...

O objetivo deste artigo é fazer uma análise exploratória inicial das atividades inovativas das em... more O objetivo deste artigo é fazer uma análise exploratória inicial das atividades inovativas das empresas de serviços de Minas Gerais nos setores de serviços intensivos em conhecimento. Para tanto, utilizam-se os dados regionalizados das edições de 2008 e 2011 da PINTEC/IBGE. Os resultados.sugerem que investimentos em atividades de inovação têm trazido resultados positivos, especialmente no tocante à eficiência produtiva, o que contribuiu para melhorar a qualidade dos produtos e manter suas participações de mercado.As atividades de inovação realizadas pelas empresas de serviços do estado são majoritariamente organizacionais e se concentram nas atividades de organização do trabalho e de design.

ABSTRACT A comparative study for the fragmentation of the CH2Cl2 molecule has been performed for ... more ABSTRACT A comparative study for the fragmentation of the CH2Cl2 molecule has been performed for collisions with 0.2-2.0 MeV H+ beam and 12.0-90.0 eV photons using the time-of-flight coincidence technique. As opposed to the photoionization case, the abundances in the mass spectra are not strongly dependent on the proton collision energy. The main observed fragment, in the proton impact case, was associated to the detachment of a chlorine atom. Combing the information from the molecular orbital energies, one estimates their relative contributions to the total ionization of CH2Cl2 by proton impact.

A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil i... more A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil identifica diferenças na distribuição regional dos recursos científicos e tecnológicos. Nosso objetivo é contribuir para a discussão sobre o assunto, analisando a dinâmica da produção de novos conhecimentos científicos nos estados que mais contribuem para a produção científica nacional, ou seja, São Paulo, Rio de Janeiro, Minas Gerais e Rio Grande do Sul ('quarteto científico') no período de 2000 a 2010. A hipótese específica deste estudo é que, mesmo com as políticas federais voltadas para a ampliação e descentralização da produção de novos conhecimentos científicos, sua produção ainda é fortemente ancorada no 'quarteto científico'. Identificamos ainda uma concentração da produção científica em três grandes áreas do conhecimento: ciências agrárias, biológicas e da saúde.

A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil i... more A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil identifica diferenças na distribuição regional dos recursos científicos e tecnológicos. Nosso objetivo é contribuir para a discussão sobre o assunto, analisando a dinâmica da produção de novos conhecimentos científicos nos estados que mais contribuem para a produção científica nacional, ou seja, São Paulo, Rio de Janeiro, Minas Gerais e Rio Grande do Sul ('quarteto científico') no período de 2000 a 2010. A hipótese específica deste estudo é que, mesmo com as políticas federais voltadas para a ampliação e descentralização da produção de novos conhecimentos científicos, sua produção ainda é fortemente ancorada no 'quarteto científico'. Identificamos ainda uma concentração da produção científica em três grandes áreas do conhecimento: ciências agrárias, biológicas e da saúde.

A comparative study for the fragmentation of a CH 2 Cl 2 molecule has been performed for collisio... more A comparative study for the fragmentation of a CH 2 Cl 2 molecule has been performed for collisions with 0.2-2.0 MeV H + beam and 12.0-90.0 eV photons using the time-of-flight coincidence technique. Branching ratios for fragmentation products have been determined as a function of the energy of the projectiles. The present results show that the more the proton energy increases, the more the fragmentation pattern resembles the corresponding photon impact spectra at lower energies. For instance, at 2.0 MeV proton impact, the fragmentation pattern closely resembles the corresponding photon impact pattern at hν = 60 eV. From the analysis of the peak shapes, the fragmentation products were found to be formed with low kinetic energies (<1 eV). The main observed fragments, in the proton impact case and for photons above 30 eV, were associated with the release of a chlorine atom. Combining the information from the molecular orbital energies, one estimates the relative contributions of the molecular orbitals to the total ionization of CH 2 Cl 2 by proton impact. It is also shown for the first time that the fragmentation pattern for charged products in the proton impact spectra can be directly compared to the corresponding fragmentation pattern for photon impact, through the transferred momentum, which depends on the projectile velocity as v −1 . This is a clear indication that the main dynamical variable behind the branching ratios is the momentum transfer at high velocities.

Salt marsh sediments are sinks for various anthropogenic contaminants, giving rise to significant... more Salt marsh sediments are sinks for various anthropogenic contaminants, giving rise to significant environmental concern. The process of salt marsh plant survival in such environment is very intriguing and at the same time poorly understood. The plant-microbe interactions may play a key role in the process of environment and in planta detoxification. In this study, a combination of culture-dependent and culture-independent molecular approaches [enrichment cultures, polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), DNA sequencing] were used to investigate the effect of petroleum hydrocarbons (PH) contamination on the structure and function [polycyclic aromatic hydrocarbon (PAH) dioxygenase genes] of endophytic bacterial communities of salt marsh plant species (Halimione portulacoides and Sarcocornia perennis) in the estuarine system Ria de Aveiro (Portugal). Pseudomonads dominated the cultivable fraction of the endophytic communities in the enrichment cultures. In a set of fifty isolates tested, nine were positive for genes encoding for PAH dioxygenases (nahAc) and four were positive for plasmid carrying genes encoding PAH degradation enzymes (nahAc). Interestingly, these plasmids were only detected in isolates from most severely PH-polluted sites. The results revealed site-specific effects on endophytic communities, related to the level of PH contamination in the sediment, and plant-species-specific 'imprints' in community structure and in genes encoding for PAH dioxygenases. These results suggest a potential ecological role of bacterial plant symbiosis in the process of plant colonization in urban estuarine areas exposed to PH contamination.

Heterotrophic bacteria are key players in the processes of organic matter recycling, decompositio... more Heterotrophic bacteria are key players in the processes of organic matter recycling, decomposition and mineralization in aquatic environments. Although only small and chemically simple compounds can be passively transported through bacterial membranes, substrates for bacterial utilization in aquatic environments are dominated by particulate or highmolecular-weight dissolved organic matter. Complex substrates must first be hydrolyzed outside the cell into smaller size molecules by extracellular enzymes and this process represents a limiting step in nutrient cycling. Bacterial extracellular enzymatic activity is regulated at the ecosystem level, by environmental factors and at the micro-environment level by enzyme-substrate interactions. Over the last century, changes in the atmosphere concentration of CO 2 and other greenhouse gases caused changes in climate patterns that have repercussions in ecosystem function and biodiversity. Microorganisms are generally able to respond very quickly to environmental changes because of their close contact with the surrounding environment and rapid growth. As mediators in important biogeochemical processes, namely decomposition and transformation of organic matter, release of inorganic nutrients for higher trophic levels and detoxification of xenobiotics, bacterial enzyme activities have the potential to be used as descriptors of biological responses to changing environmental conditions. The present paper reviews the currently available information on environmental regulation of bacterial extracellular enzymatic activity in aquatic environments and discusses the potential implications of direct and indirect effects global changes on heterotrophic bacterial communities and on the processes of organic matter recycling.

We compare the environmental characteristics and bacterial communities associated with two rushes... more We compare the environmental characteristics and bacterial communities associated with two rushes, Juncus maritimus and Bolboschoenus maritimus, and adjacent unvegetated habitat in a salt marsh subjected to historical mercury pollution. Mercury content was higher in vegetated than unvegetated habitat and increased with sampling depth. There was also a significant relationship between mercury concentration and bacterial composition. Habitat (Juncus, Bolboschoenus or unvegetated), sample depth, and the interaction between both, however, explained most of the variation in composition ($70%). Variation in composition with depth was most prominent for the unvegetated habitat, followed by Juncus, but more constrained for Bolboschoenus habitat. This constraint may be indicative of a strong plant-microbe ecophysiological adaptation. Vegetated habitat contained distinct bacterial communities associated with higher potential activity of aminopeptidase, b-glucosidase and arylsulphatase and incorporation rates of 14 C-glucose and 14 C-acetate. Communities in unvegetated habitat were, in contrast, associated with both higher pH and proportion of sulphate reducing bacteria.

Microbial ecology, 2010

The aim of this study was to understand if two species of salt marsh plants, widely distributed i... more The aim of this study was to understand if two species of salt marsh plants, widely distributed in European estuaries (Spartina maritima and Halimione portulacoides) differently influence the distribution, activity, and metabolic physiology of sediment bacterial communities in monospecific banks, in comparison with uncolonized sediment (control). Microbiological descriptors of abundance and activity were assessed along vertical profiles of sediments. Rates of activity of the extracellular enzymes β-glucosidase, α-glucosidase, aminopeptidase, arylsulfatase, and phosphatase were generally higher in the vegetation banks in relation to control sediments where they were also less variable with depth. This is interpreted as an indirect effect related to supply of plant-derived polymeric substrates for bacterial growth. Parameters related to sediment texture (grain size, percent of fines or water content) showed significant relations with cell abundance or maximum hydrolysis rates, pointing to an indirect effect of plant colonization exerted through the modification of sediment physical properties. The profiles of utilization of sole-carbon-source (Biolog Ecoplates) showed that only the communities from the upper sediment layer of the S. maritima and the H. portulacoides banks exhibit consistent differences in terms of physiological profiles. Bacterial communities in control sediments exhibited the lowest physiological variability between surface and sub-surface communities. The results indicate that microbial colonization and organic matter decomposition are enhanced under the influence of salt marsh plants and confirm that plant coverage is a major determinant of the processes of organic matter recycling in intertidal estuarine sediments.

Microbial Ecology, 2014

Estuaries are sinks for various anthropogenic contaminants, such as petroleum hydrocarbons, givin... more Estuaries are sinks for various anthropogenic contaminants, such as petroleum hydrocarbons, giving rise to significant environmental concern. The demand for organisms and processes capable of degrading pollutants in a clean, effective, and less expensive process is of great importance. Phytoremedition approaches involving plant/bacteria interactions have been explored as an alternative, and halophyte vegetation has potential for use in phytoremedition of hydrocarbon contamination. Studies with plant species potentially suitable for microbe-assisted phytoremediation are widely represented in scientific literature. However, the in-depth understanding of the biological processes associated with the reintroduction of indigenous bacteria and plants and their performance in the degradation of hydrocarbons is still the limiting step for the application of these bioremediation solutions in a field context. The intent of the present review is to summarize the sources and effects of hydrocarbon contamination in estuarine environments, the strategies currently available for bioremediation (potential and limitations), and the perspectives of the use of halophyte plants in microbeassisted phytoremediation approaches.

Applied and …, 2012

The effects of UV radiation (UVR) on estuarine bacterioneuston and bacterioplankton were assessed... more The effects of UV radiation (UVR) on estuarine bacterioneuston and bacterioplankton were assessed in microcosm experiments. Bacterial abundance and DNA synthesis were more affected in bacterioplankton. Protein synthesis was more inhibited in bacterioneuston. Community analysis indicated that UVR has the potential to select resistant bacteria (e.g., Gammaproteobacteria), particularly abundant in bacterioneuston. FIG 1 UV-B dose-dependent variation of abundance of culturable bacteria (A) and total prokaryote abundance (B). Results are expressed as percentages of those for the dark controls. Mean values of triplicate determinations in three subsamples from three independent experiments (n ϭ 27) were plotted. Error bars represent standard deviations. The absence of error bars indicates that standard deviations are too small to see on the scale used.

RESUMO O objetivo deste artigo é investigar os padrões de interação de empresas nacionais e multi... more RESUMO O objetivo deste artigo é investigar os padrões de interação de empresas nacionais e multinacionais localizadas no Brasil com universidades/institutos públicos de pesquisa (IPPs) presentes no país. Para tanto, utilizou-se uma base de dados que envolve 319 ...

O objetivo deste artigo é fazer uma análise exploratória inicial das atividades inovativas das em... more O objetivo deste artigo é fazer uma análise exploratória inicial das atividades inovativas das empresas de serviços de Minas Gerais nos setores de serviços intensivos em conhecimento. Para tanto, utilizam-se os dados regionalizados das edições de 2008 e 2011 da PINTEC/IBGE. Os resultados.sugerem que investimentos em atividades de inovação têm trazido resultados positivos, especialmente no tocante à eficiência produtiva, o que contribuiu para melhorar a qualidade dos produtos e manter suas participações de mercado.As atividades de inovação realizadas pelas empresas de serviços do estado são majoritariamente organizacionais e se concentram nas atividades de organização do trabalho e de design.

ABSTRACT A comparative study for the fragmentation of the CH2Cl2 molecule has been performed for ... more ABSTRACT A comparative study for the fragmentation of the CH2Cl2 molecule has been performed for collisions with 0.2-2.0 MeV H+ beam and 12.0-90.0 eV photons using the time-of-flight coincidence technique. As opposed to the photoionization case, the abundances in the mass spectra are not strongly dependent on the proton collision energy. The main observed fragment, in the proton impact case, was associated to the detachment of a chlorine atom. Combing the information from the molecular orbital energies, one estimates their relative contributions to the total ionization of CH2Cl2 by proton impact.

A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil i... more A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil identifica diferenças na distribuição regional dos recursos científicos e tecnológicos. Nosso objetivo é contribuir para a discussão sobre o assunto, analisando a dinâmica da produção de novos conhecimentos científicos nos estados que mais contribuem para a produção científica nacional, ou seja, São Paulo, Rio de Janeiro, Minas Gerais e Rio Grande do Sul ('quarteto científico') no período de 2000 a 2010. A hipótese específica deste estudo é que, mesmo com as políticas federais voltadas para a ampliação e descentralização da produção de novos conhecimentos científicos, sua produção ainda é fortemente ancorada no 'quarteto científico'. Identificamos ainda uma concentração da produção científica em três grandes áreas do conhecimento: ciências agrárias, biológicas e da saúde.

A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil i... more A literatura que analisa a distribuição espacial da produção científica e tecnológica no Brasil identifica diferenças na distribuição regional dos recursos científicos e tecnológicos. Nosso objetivo é contribuir para a discussão sobre o assunto, analisando a dinâmica da produção de novos conhecimentos científicos nos estados que mais contribuem para a produção científica nacional, ou seja, São Paulo, Rio de Janeiro, Minas Gerais e Rio Grande do Sul ('quarteto científico') no período de 2000 a 2010. A hipótese específica deste estudo é que, mesmo com as políticas federais voltadas para a ampliação e descentralização da produção de novos conhecimentos científicos, sua produção ainda é fortemente ancorada no 'quarteto científico'. Identificamos ainda uma concentração da produção científica em três grandes áreas do conhecimento: ciências agrárias, biológicas e da saúde.

A comparative study for the fragmentation of a CH 2 Cl 2 molecule has been performed for collisio... more A comparative study for the fragmentation of a CH 2 Cl 2 molecule has been performed for collisions with 0.2-2.0 MeV H + beam and 12.0-90.0 eV photons using the time-of-flight coincidence technique. Branching ratios for fragmentation products have been determined as a function of the energy of the projectiles. The present results show that the more the proton energy increases, the more the fragmentation pattern resembles the corresponding photon impact spectra at lower energies. For instance, at 2.0 MeV proton impact, the fragmentation pattern closely resembles the corresponding photon impact pattern at hν = 60 eV. From the analysis of the peak shapes, the fragmentation products were found to be formed with low kinetic energies (<1 eV). The main observed fragments, in the proton impact case and for photons above 30 eV, were associated with the release of a chlorine atom. Combining the information from the molecular orbital energies, one estimates the relative contributions of the molecular orbitals to the total ionization of CH 2 Cl 2 by proton impact. It is also shown for the first time that the fragmentation pattern for charged products in the proton impact spectra can be directly compared to the corresponding fragmentation pattern for photon impact, through the transferred momentum, which depends on the projectile velocity as v −1 . This is a clear indication that the main dynamical variable behind the branching ratios is the momentum transfer at high velocities.

Salt marsh sediments are sinks for various anthropogenic contaminants, giving rise to significant... more Salt marsh sediments are sinks for various anthropogenic contaminants, giving rise to significant environmental concern. The process of salt marsh plant survival in such environment is very intriguing and at the same time poorly understood. The plant-microbe interactions may play a key role in the process of environment and in planta detoxification. In this study, a combination of culture-dependent and culture-independent molecular approaches [enrichment cultures, polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), DNA sequencing] were used to investigate the effect of petroleum hydrocarbons (PH) contamination on the structure and function [polycyclic aromatic hydrocarbon (PAH) dioxygenase genes] of endophytic bacterial communities of salt marsh plant species (Halimione portulacoides and Sarcocornia perennis) in the estuarine system Ria de Aveiro (Portugal). Pseudomonads dominated the cultivable fraction of the endophytic communities in the enrichment cultures. In a set of fifty isolates tested, nine were positive for genes encoding for PAH dioxygenases (nahAc) and four were positive for plasmid carrying genes encoding PAH degradation enzymes (nahAc). Interestingly, these plasmids were only detected in isolates from most severely PH-polluted sites. The results revealed site-specific effects on endophytic communities, related to the level of PH contamination in the sediment, and plant-species-specific 'imprints' in community structure and in genes encoding for PAH dioxygenases. These results suggest a potential ecological role of bacterial plant symbiosis in the process of plant colonization in urban estuarine areas exposed to PH contamination.

Heterotrophic bacteria are key players in the processes of organic matter recycling, decompositio... more Heterotrophic bacteria are key players in the processes of organic matter recycling, decomposition and mineralization in aquatic environments. Although only small and chemically simple compounds can be passively transported through bacterial membranes, substrates for bacterial utilization in aquatic environments are dominated by particulate or highmolecular-weight dissolved organic matter. Complex substrates must first be hydrolyzed outside the cell into smaller size molecules by extracellular enzymes and this process represents a limiting step in nutrient cycling. Bacterial extracellular enzymatic activity is regulated at the ecosystem level, by environmental factors and at the micro-environment level by enzyme-substrate interactions. Over the last century, changes in the atmosphere concentration of CO 2 and other greenhouse gases caused changes in climate patterns that have repercussions in ecosystem function and biodiversity. Microorganisms are generally able to respond very quickly to environmental changes because of their close contact with the surrounding environment and rapid growth. As mediators in important biogeochemical processes, namely decomposition and transformation of organic matter, release of inorganic nutrients for higher trophic levels and detoxification of xenobiotics, bacterial enzyme activities have the potential to be used as descriptors of biological responses to changing environmental conditions. The present paper reviews the currently available information on environmental regulation of bacterial extracellular enzymatic activity in aquatic environments and discusses the potential implications of direct and indirect effects global changes on heterotrophic bacterial communities and on the processes of organic matter recycling.

We compare the environmental characteristics and bacterial communities associated with two rushes... more We compare the environmental characteristics and bacterial communities associated with two rushes, Juncus maritimus and Bolboschoenus maritimus, and adjacent unvegetated habitat in a salt marsh subjected to historical mercury pollution. Mercury content was higher in vegetated than unvegetated habitat and increased with sampling depth. There was also a significant relationship between mercury concentration and bacterial composition. Habitat (Juncus, Bolboschoenus or unvegetated), sample depth, and the interaction between both, however, explained most of the variation in composition ($70%). Variation in composition with depth was most prominent for the unvegetated habitat, followed by Juncus, but more constrained for Bolboschoenus habitat. This constraint may be indicative of a strong plant-microbe ecophysiological adaptation. Vegetated habitat contained distinct bacterial communities associated with higher potential activity of aminopeptidase, b-glucosidase and arylsulphatase and incorporation rates of 14 C-glucose and 14 C-acetate. Communities in unvegetated habitat were, in contrast, associated with both higher pH and proportion of sulphate reducing bacteria.

Microbial ecology, 2010

The aim of this study was to understand if two species of salt marsh plants, widely distributed i... more The aim of this study was to understand if two species of salt marsh plants, widely distributed in European estuaries (Spartina maritima and Halimione portulacoides) differently influence the distribution, activity, and metabolic physiology of sediment bacterial communities in monospecific banks, in comparison with uncolonized sediment (control). Microbiological descriptors of abundance and activity were assessed along vertical profiles of sediments. Rates of activity of the extracellular enzymes β-glucosidase, α-glucosidase, aminopeptidase, arylsulfatase, and phosphatase were generally higher in the vegetation banks in relation to control sediments where they were also less variable with depth. This is interpreted as an indirect effect related to supply of plant-derived polymeric substrates for bacterial growth. Parameters related to sediment texture (grain size, percent of fines or water content) showed significant relations with cell abundance or maximum hydrolysis rates, pointing to an indirect effect of plant colonization exerted through the modification of sediment physical properties. The profiles of utilization of sole-carbon-source (Biolog Ecoplates) showed that only the communities from the upper sediment layer of the S. maritima and the H. portulacoides banks exhibit consistent differences in terms of physiological profiles. Bacterial communities in control sediments exhibited the lowest physiological variability between surface and sub-surface communities. The results indicate that microbial colonization and organic matter decomposition are enhanced under the influence of salt marsh plants and confirm that plant coverage is a major determinant of the processes of organic matter recycling in intertidal estuarine sediments.

Microbial Ecology, 2014

Estuaries are sinks for various anthropogenic contaminants, such as petroleum hydrocarbons, givin... more Estuaries are sinks for various anthropogenic contaminants, such as petroleum hydrocarbons, giving rise to significant environmental concern. The demand for organisms and processes capable of degrading pollutants in a clean, effective, and less expensive process is of great importance. Phytoremedition approaches involving plant/bacteria interactions have been explored as an alternative, and halophyte vegetation has potential for use in phytoremedition of hydrocarbon contamination. Studies with plant species potentially suitable for microbe-assisted phytoremediation are widely represented in scientific literature. However, the in-depth understanding of the biological processes associated with the reintroduction of indigenous bacteria and plants and their performance in the degradation of hydrocarbons is still the limiting step for the application of these bioremediation solutions in a field context. The intent of the present review is to summarize the sources and effects of hydrocarbon contamination in estuarine environments, the strategies currently available for bioremediation (potential and limitations), and the perspectives of the use of halophyte plants in microbeassisted phytoremediation approaches.

Applied and …, 2012

The effects of UV radiation (UVR) on estuarine bacterioneuston and bacterioplankton were assessed... more The effects of UV radiation (UVR) on estuarine bacterioneuston and bacterioplankton were assessed in microcosm experiments. Bacterial abundance and DNA synthesis were more affected in bacterioplankton. Protein synthesis was more inhibited in bacterioneuston. Community analysis indicated that UVR has the potential to select resistant bacteria (e.g., Gammaproteobacteria), particularly abundant in bacterioneuston. FIG 1 UV-B dose-dependent variation of abundance of culturable bacteria (A) and total prokaryote abundance (B). Results are expressed as percentages of those for the dark controls. Mean values of triplicate determinations in three subsamples from three independent experiments (n ϭ 27) were plotted. Error bars represent standard deviations. The absence of error bars indicates that standard deviations are too small to see on the scale used.