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1.
Sci Total Environ ; 672: 502-514, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30965264

RESUMO

Carbon dioxide (CO2) is the main greenhouse gas (GHG) and its atmospheric concentration is currently 50% higher than pre-industrial levels. The continuous GHGs emissions may lead to severe and irreversible consequences in the climate system. The reduction of GHG emissions may be not enough to mitigate climate change. Consequently, besides carbon capture from large emission sources, atmospheric CO2 capture may be also required. To meet the target defined for climate change mitigation, the removal of 10 Gt·yr-1 of CO2 globally by mid-century and 20 Gt·yr-1 of CO2 globally by the end of century. The technologies applied with this aim are known as negative emission technologies (NETs), as they lead to achieve a negative balance of carbon in atmosphere. This paper aims to present the recent research works regarding NETs, focusing the research findings achieved by academic groups and projects. Besides several advantages, NETs present high operational cost and its scale-up should be tested to know the real effect on climate change mitigation. With current knowledge, no single process should be seen as a solution. Research efforts should be performed to evaluate and reduce NETs costs and environmental impact.

2.
Front Plant Sci ; 9: 553, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29922307

RESUMO

Current morphometric methods that comprehensively measure shape cannot compare the disparate leaf shapes found in seed plants and are sensitive to processing artifacts. We explore the use of persistent homology, a topological method applied as a filtration across simplicial complexes (or more simply, a method to measure topological features of spaces across different spatial resolutions), to overcome these limitations. The described method isolates subsets of shape features and measures the spatial relationship of neighboring pixel densities in a shape. We apply the method to the analysis of 182,707 leaves, both published and unpublished, representing 141 plant families collected from 75 sites throughout the world. By measuring leaves from throughout the seed plants using persistent homology, a defined morphospace comparing all leaves is demarcated. Clear differences in shape between major phylogenetic groups are detected and estimates of leaf shape diversity within plant families are made. The approach predicts plant family above chance. The application of a persistent homology method, using topological features, to measure leaf shape allows for a unified morphometric framework to measure plant form, including shapes, textures, patterns, and branching architectures.

3.
Trends Plant Sci ; 21(12): 1008-1016, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27789157

RESUMO

In eukaryotes, protein deacetylation is carried out by two well-conserved histone deacetylase (HDAC) families: RPD3/HDA1 and SIR2. Intriguingly, model plants such as Arabidopsis express an additional plant-specific HDAC family, termed type-2 HDACs (HD2s). Transcriptomic analyses from more than 1300 green plants generated by the 1000 plants (1KP) consortium showed that HD2s appeared early in green plant evolution, the first members being detected in several streptophyte green alga. The HD2 family has expanded via several rounds of successive duplication; members are expressed in all major green plant clades. Interestingly, angiosperm species express new HD2 genes devoid of a zinc-finger domain, one of the main structural features of HD2s. These variants may have been associated with the origin and/or the biology of the ovule/seed.


Assuntos
Histona Desacetilases/metabolismo , Proteínas de Plantas/metabolismo , Viridiplantae/metabolismo , Regulação da Expressão Gênica de Plantas , Histona Desacetilases/genética , Proteínas de Plantas/genética , Viridiplantae/genética
4.
Environ Sci Pollut Res Int ; 21(17): 10550-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24854500

RESUMO

The effect of meteorological variables on surface ozone (O3) concentrations was analysed based on temporal variation of linear correlation and artificial neural network (ANN) models defined by genetic algorithms (GAs). ANN models were also used to predict the daily average concentration of this air pollutant in Campo Grande, Brazil. Three methodologies were applied using GAs, two of them considering threshold models. In these models, the variables selected to define different regimes were daily average O3 concentration, relative humidity and solar radiation. The threshold model that considers two O3 regimes was the one that correctly describes the effect of important meteorological variables in O3 behaviour, presenting also a good predictive performance. Solar radiation, relative humidity and rainfall were considered significant for both O3 regimes; however, wind speed (dispersion effect) was only significant for high concentrations. According to this model, high O3 concentrations corresponded to high solar radiation, low relative humidity and wind speed. This model showed to be a powerful tool to interpret the O3 behaviour, being useful to define policy strategies for human health protection regarding air pollution.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/estatística & dados numéricos , Redes Neurais de Computação , Ozônio/análise , Brasil , Monitoramento Ambiental/métodos , Previsões , Umidade , Meteorologia/métodos , Fatores de Tempo , Vento
5.
Environ Sci Pollut Res Int ; 20(8): 5096-105, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23673923

RESUMO

Microalgae culture is still not economically viable and it presents some negative environmental impacts, concerning water, nutrient and energy requirements. In this context, this study aims to review the recent advances on microalgal cultures in wastewaters to enhance their economic viability. We focused on three different culture concepts: (1) suspended cell systems, (2) cell immobilization, and (3) microalgae consortia. Cultures with suspended cells are the most studied. The nutrient removal efficiencies are usually high for wastewaters of different sources. However, biomass harvesting is difficult and a costly process due to the small cell size and lower culture density. On the other hand, the cell immobilization systems showed to be the solution for this problem, having as main limitation the nutrient diffusion from bulk to cells, which results in a reduced nutrient removal efficiency. The consortium between microalgae and bacteria enhances the growth of both microorganisms. This culture concept showed to be a promising technology to improve wastewater treatment, regarding not only nutrient removal but also biomass harvesting by bioflocculation. The aggregation mechanism must be studied in depth to find the process parameters that would lead to an effective and cheap harvesting process.


Assuntos
Microalgas , Águas Residuárias/microbiologia , Poluição do Ar/prevenção & controle , Biocombustíveis , Técnicas de Cultura de Células , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/métodos
6.
Environ Sci Pollut Res Int ; 20(6): 3932-45, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23184127

RESUMO

This study aimed to characterize air pollution and the associated carcinogenic risks of polycyclic aromatic hydrocarbon (PAHs) at an urban site, to identify possible emission sources of PAHs using several statistical methodologies, and to analyze the influence of other air pollutants and meteorological variables on PAH concentrations.The air quality and meteorological data were collected in Oporto, the second largest city of Portugal. Eighteen PAHs (the 16 PAHs considered by United States Environment Protection Agency (USEPA) as priority pollutants, dibenzo[a,l]pyrene, and benzo[j]fluoranthene) were collected daily for 24 h in air (gas phase and in particles) during 40 consecutive days in November and December 2008 by constant low-flow samplers and using polytetrafluoroethylene (PTFE) membrane filters for particulate (PM10 and PM2.5 bound) PAHs and pre-cleaned polyurethane foam plugs for gaseous compounds. The other monitored air pollutants were SO2, PM10, NO2, CO, and O3; the meteorological variables were temperature, relative humidity, wind speed, total precipitation, and solar radiation. Benzo[a]pyrene reached a mean concentration of 2.02 ng m(-3), surpassing the EU annual limit value. The target carcinogenic risks were equal than the health-based guideline level set by USEPA (10(-6)) at the studied site, with the cancer risks of eight PAHs reaching senior levels of 9.98 × 10(-7) in PM10 and 1.06 × 10(-6) in air. The applied statistical methods, correlation matrix, cluster analysis, and principal component analysis, were in agreement in the grouping of the PAHs. The groups were formed according to their chemical structure (number of rings), phase distribution, and emission sources. PAH diagnostic ratios were also calculated to evaluate the main emission sources. Diesel vehicular emissions were the major source of PAHs at the studied site. Besides that source, emissions from residential heating and oil refinery were identified to contribute to PAH levels at the respective area. Additionally, principal component regression indicated that SO2, NO2, PM10, CO, and solar radiation had positive correlation with PAHs concentrations, while O3, temperature, relative humidity, and wind speed were negatively correlated.


Assuntos
Poluição do Ar/análise , Carcinógenos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Adolescente , Adulto , Idoso , Poluentes Atmosféricos/análise , Testes de Carcinogenicidade , Criança , Pré-Escolar , Cidades , Monitoramento Ambiental/métodos , Humanos , Lactente , Pessoa de Meia-Idade , Portugal , Análise de Componente Principal , Medição de Risco , Fatores de Risco , Dióxido de Enxofre/análise , Adulto Jovem
7.
Environ Int ; 44: 18-25, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22387227

RESUMO

Exposure to air pollution has been related with the most varied adverse health outcomes. This study aims to assess the impact of air pollution on the emergency hospitalization for respiratory disease in Rio de Janeiro, Brazil. The study was divided in two parts: Part I specifically addressing the air pollution assessment and Part II addressing the health assessment. Accordingly, this Part I aims to: i) evaluate the concentrations of PM(10), SO(2) and CO at two sites in Rio de Janeiro and compare them; ii) analyse the concentrations observed according to the national and international standards; and iii) analyse the air pollutants behaviour, namely, annually, seasonally, daily and considering weekdays/weekends variations. The pollutant concentrations were measured at two different sites in Rio de Janeiro and the analysis was performed for the period between September 2000 and December 2005. Results showed that PM(10) concentrations in Rio de Janeiro exceeded the daily and annual standards imposed by the European Union, the Brazilian legislation and WHO guidelines. Regarding SO(2) and CO, concentrations were, generally, below both European and Brazilian standards. Nevertheless, considering WHO guidelines, SO(2) threshold for daily concentrations (20 µg m(-3)) was exceeded around 150 times. Behaviour assessment showed that the influence of traffic is a major factor affecting the air pollution in Rio de Janeiro. Considering the results achieved and the proven health effects of air pollution, strategies should be defined for its reduction, particularly concerning particulate matter, and consequently contribute to the protection of public health.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Doenças Respiratórias/epidemiologia , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Brasil , Monóxido de Carbono/análise , Humanos , Morbidade , Material Particulado/análise , Doenças Respiratórias/induzido quimicamente , Dióxido de Enxofre/análise
8.
Environ Int ; 43: 1-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22446713

RESUMO

The effects of air pollution on health have been studied worldwide. Given that air pollution triggers oxidative stress and inflammation, it is plausible that high levels of air pollutants cause higher number of hospitalisations. This study aimed to assess the impact of air pollution on the emergency hospitalisation for respiratory disease in Rio de Janeiro, Brazil. The study was divided in two parts: Part I specifically addressing the air pollution assessment and Part II addressing the health assessment. Accordingly, this Part II aimed to estimate the association between the concentrations of PM10, SO2 and CO observed in Rio de Janeiro and the number of emergency hospitalisations at a central hospital due to respiratory diseases. The pollutant concentrations were measured at two different sites in Rio de Janeiro, but the excess relative risks were calculated based on the concentrations observed at one of the sites, where limits were generally exceeded more frequently, between September 2000 and December 2005. A time series analysis was performed using the number of hospitalisations, divided in three categories (children until 1 year old, children aged between 1 and 5 years old and elderly with 65 years old or more) as independent variable, the concentrations of pollutants as dependent variables and temperature, relative humidity, long term trend, and seasonality as confounders. Data were analysed using generalised additive models with smoothing for some of the dependent variables. Results showed an excess risk of hospitalisation for respiratory disease higher than 2% per 10 µg m⁻³ increase in PM10 concentrations for children under 5 years old, of 2% per 10 µg m⁻³ increase in SO2 for elderly above 65 years old and around 0.1% per 10 µg m⁻³ increase in CO for children under 1 year and elderly. Other studies have found associations that are in agreement with the results achieved in this study. The study suggests that the ambient levels of air pollutants experienced in Rio de Janeiro between 2000 and 2005 were linked to the number of hospitalisations for respiratory diseases among children and elderly.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Doenças Respiratórias/epidemiologia , Idoso , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Brasil , Monóxido de Carbono/análise , Pré-Escolar , Exposição Ambiental/análise , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Morbidade , Material Particulado/análise , Medição de Risco , Dióxido de Enxofre/análise
9.
Environ Sci Pollut Res Int ; 19(8): 3228-34, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22382697

RESUMO

INTRODUCTION: This study proposes three methodologies to define artificial neural network models through genetic algorithms (GAs) to predict the next-day hourly average surface ozone (O(3)) concentrations. GAs were applied to define the activation function in hidden layer and the number of hidden neurons. METHODS: Two of the methodologies define threshold models, which assume that the behaviour of the dependent variable (O(3) concentrations) changes when it enters in a different regime (two and four regimes were considered in this study). The change from one regime to another depends on a specific value (threshold value) of an explanatory variable (threshold variable), which is also defined by GAs. The predictor variables were the hourly average concentrations of carbon monoxide (CO), nitrogen oxide, nitrogen dioxide (NO(2)), and O(3) (recorded in the previous day at an urban site with traffic influence) and also meteorological data (hourly averages of temperature, solar radiation, relative humidity and wind speed). The study was performed for the period from May to August 2004. RESULTS AND DISCUSSION: Several models were achieved and only the best model of each methodology was analysed. In threshold models, the variables selected by GAs to define the O(3) regimes were temperature, CO and NO(2) concentrations, due to their importance in O(3) chemistry in an urban atmosphere. CONCLUSION: In the prediction of O(3) concentrations, the threshold model that considers two regimes was the one that fitted the data most efficiently.


Assuntos
Algoritmos , Atmosfera/química , Monitoramento Ambiental/métodos , Redes Neurais de Computação , Ozônio/análise , Monóxido de Carbono/química , Conceitos Meteorológicos , Modelos Químicos , Dióxido de Nitrogênio/química , Óxidos de Nitrogênio/química
10.
Genome ; 53(8): 619-29, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20725149

RESUMO

The Brassica B-genome species possess many valuable agronomic and disease resistance traits. To transfer traits from the B genome of B. carinata into B. napus, an interspecific cross between B. napus and B. carinata was performed and a doubled haploid (DH) population was generated from the BC2S3 generation. Successful production of interspecific DH lines as identified using B-genome microsatellite markers is reported. Five percent of DH lines carry either intact B-genome chromosomes or chromosomes that have deletions. All of the DH lines have linkage group J13/B7 in common. This was further confirmed using B. nigra genomic DNA in a fluorescent in situ hybridization assay where the B-genome chromosomes were visualized and distinguished from the A- and C-genome chromosomes. The 60 DH lines were also evaluated for morphological traits in the field for two seasons and were tested for resistance to blackleg, caused by Leptosphaeria maculans, under greenhouse conditions. Variation in the DH population followed a normal distribution for several agronomic traits and response to blackleg. The lines with B-genome chromosomes were significantly different (p < 0.01) from the lines without B-genome chromosomes for both morphological and seed quality traits such as days to flowering, days to maturity, and erucic acid content.


Assuntos
Brassica napus/genética , Brassica/genética , Cromossomos de Plantas/genética , Genoma de Planta/genética , Haploidia , Mapeamento Cromossômico , Cruzamentos Genéticos , Genética Populacional , Genoma de Planta/fisiologia , Genótipo , Células Híbridas/metabolismo , Hibridização Genética/fisiologia , Hibridização in Situ Fluorescente
11.
Cytogenet Genome Res ; 129(1-3): 190-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20628251

RESUMO

Bacterial artificial chromosome (BAC) contigs have been genetically mapped to the 10 linkage groups of Brassica rapa by BAC end sequences (BES). To integrate the genetic, physical, and cytogenetic maps, fluorescence in situ hybridization (FISH) was used to anchor the assembly of BAC contigs onto Brassica chromosomes using representative BACs. This BAC-FISH approach can be used to identify chromosome arms on separate mitotic metaphase chromosomes or to map multiple BACs to single long pachytene chromosomes. As part of an international consortium that is sequencing the B. rapa genome, we integrated the linkage and physical maps with the B. rapa cytogenetic map for chromosome A7 by hybridizing BACs to mitotic chromosomes and along the length of pachytene chromosome spreads. A total of 31 BACs that were putatively located on A7 were used as probes for FISH analyses; however, only 19 BACs mapped unambiguously to A7 while the remaining BACs either mapped to other chromosomes or hybridized to multiple locations. We then created a multicolor FISH cocktail of 16 BAC probes to simultaneously hybridize the entire length of the A7 chromosome. We successfully applied the 16 A7 BAC probe mix to B. rapa, B. oleracea, and domesticated and resynthesized genotypes of B. napus to demonstrate that this approach can facilitate studies of genome evolution by integrating the genetic, physical, and cytogenetic maps among closely related species of Brassica.


Assuntos
Brassica rapa/genética , Cromossomos de Plantas/genética , Análise Citogenética/métodos , Mapeamento Cromossômico , Cromossomos Artificiais Bacterianos/genética , Mapeamento de Sequências Contíguas , Marcadores Genéticos , Hibridização in Situ Fluorescente , Mapeamento Físico do Cromossomo
12.
PLoS One ; 4(3): e4760, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19274085

RESUMO

BACKGROUND: Studies in resynthesized Brassica napus allopolyploids indicate that homoeologous chromosome exchanges in advanced generations (S(5ratio6)) alter gene expression through the loss and doubling of homoeologous genes within the rearrangements. Rearrangements may also indirectly affect global gene expression if homoeologous copies of gene regulators within rearrangements have differential affects on the transcription of genes in networks. METHODOLOGY/PRINCIPAL FINDINGS: We utilized Arabidopsis 70mer oligonucleotide microarrays for exploring gene expression in three resynthesized B. napus lineages at the S(0ratio1) and S(5ratio6) generations as well as their diploid progenitors B. rapa and B. oleracea. Differential gene expression between the progenitors and additive (midparent) expression in the allopolyploids were tested. The S(5ratio6) lines differed in the number of genetic rearrangements, allowing us to test if the number of genes displaying nonadditive expression was related to the number of rearrangements. Estimates using per-gene and common variance ANOVA models indicated that 6-15% of 26,107 genes were differentially expressed between the progenitors. Individual allopolyploids showed nonadditive expression for 1.6-32% of all genes. Less than 0.3% of genes displayed nonadditive expression in all S(0ratio1) lines and 0.1-0.2% were nonadditive among all S(5ratio6) lines. Differentially expressed genes in the polyploids were over-represented by genes differential between the progenitors. The total number of differentially expressed genes was correlated with the number of genetic changes in S(5ratio6) lines under the common variance model; however, there was no relationship using a per-gene variance model, and many genes showed nonadditive expression in S(0ratio1) lines. CONCLUSIONS/SIGNIFICANCE: Few genes reproducibly demonstrated nonadditive expression among lineages, suggesting few changes resulted from a general response to polyploidization. Furthermore, our microarray analysis did not provide strong evidence that homoeologous rearrangements were a determinant of genome-wide nonadditive gene expression. In light of the inherent limitations of the Arabidopsis microarray to measure gene expression in polyploid Brassicas, further studies are warranted.


Assuntos
Arabidopsis/genética , Brassica napus/genética , Regulação da Expressão Gênica de Plantas , Poliploidia , Perfilação da Expressão Gênica/métodos , Rearranjo Gênico , Redes Reguladoras de Genes , Análise de Sequência com Séries de Oligonucleotídeos
13.
Genetics ; 169(2): 931-44, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15654116

RESUMO

We investigated concerted evolution of rRNA genes in multiple populations of Tragopogon mirus and T. miscellus, two allotetraploids that formed recurrently within the last 80 years following the introduction of three diploids (T. dubius, T. pratensis, and T. porrifolius) from Europe to North America. Using the earliest herbarium specimens of the allotetraploids (1949 and 1953) to represent the genomic condition near the time of polyploidization, we found that the parental rDNA repeats were inherited in roughly equal numbers. In contrast, in most present-day populations of both tetraploids, the rDNA of T. dubius origin is reduced and may occupy as little as 5% of total rDNA in some individuals. However, in two populations of T. mirus the repeats of T. dubius origin outnumber the repeats of the second diploid parent (T. porrifolius), indicating bidirectional concerted evolution within a single species. In plants of T. miscellus having a low rDNA contribution from T. dubius, the rDNA of T. dubius was nonetheless expressed. We have apparently caught homogenization of rDNA repeats (concerted evolution) in the act, although it has not proceeded to completion in any allopolyploid population yet examined.


Assuntos
DNA Ribossômico/genética , Evolução Molecular , Matriz Nuclear/química , Poliploidia , Tragopogon/genética , Cromossomos de Plantas , DNA de Plantas , Diploide , Genes de RNAr , Genética Populacional , Genoma de Planta , Geografia , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Polimorfismo Conformacional de Fita Simples , Mapeamento por Restrição , Sementes/crescimento & desenvolvimento , Tragopogon/citologia , Tragopogon/crescimento & desenvolvimento
14.
Theor Appl Genet ; 107(5): 773-82, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12904864

RESUMO

Using comparative genetics, genes, repetitive DNA sequences and chromosomes were studied in the Oryzeae in order to more fully exploit the rice genome sequence data. Of particular focus was Zizania palustris L., n = 15, commonly known as American wildrice. Previous work has shown that rice chromosomes 1, 4 and 9 are duplicated in wildrice. The Adh1 and Adh2 genes were sequenced and, based on phylogenetic analyses, found to be duplicated in wildrice. The majority of the sequence diversity in the Adh sequences was in intron 3, in which were found several MITE insertions. Cytological and molecular approaches were used to analyze the evolution of rDNA and centromeric repetitive sequences in the Oryzeae. In wildrice, copies of the 5S rDNA monomer were found at two loci on two different chromosomes near the centromeres, as in rice. One nucleolar organizer region (NOR) locus was found adjacent to the telomere, as in rice. RCS1, a middle repetitive sequence in rice, was present in all of the centromeres of wildrice. RCS2/CentO, the highly repetitive component of Oryza sativa L. centromeres, was conserved in eight of the Oryza species examined, but was not found in wildrice. Three other middle repetitive centromeric sequences (RCH1, RCH2/CentO and RCH3) were also examined and found to have variable evolutionary patterns between species of Oryza and Zizania.


Assuntos
Centrômero/genética , Cromossomos de Plantas/genética , Genes de Plantas , Oryza/genética , Sequências Repetitivas de Ácido Nucleico , Clonagem Molecular , DNA de Plantas/genética , DNA Ribossômico/genética , Evolução Molecular , Hibridização in Situ Fluorescente , Região Organizadora do Nucléolo , Telômero
15.
Mol Phylogenet Evol ; 12(3): 360-85, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10413629

RESUMO

Phylogenetic relationships of the five families of the order Commelinales remain an area of deep uncertainty in higher-level monocot systematics, despite intensive morphological and anatomical study. To test the monophyly of the Commelinales and the subclass Commelinidae, evaluate their relationships, and analyze evolutionary trends in their morphology, ecology, and biogeography, we conducted parsimony analyses on 95 rbcL sequences representing 17 taxa of Commelinales, 16 taxa of other Commelinidae, and 63 taxa from Arecidae, Liliidae, and Zingiberidae. Commelinales is polyphyletic and Commelinidae paraphyletic, with Eriocaulaceae and Xyridaceae sister to Poaceae and its relatives, Rapateaceae sister to Bromeliaceae and Mayacaceae, and Commelinaceae sister to Philydrales and allies. Thurnia is sister to Prionium at the base of Cyperaceae-Juncaceae; only 1 of Cronquist's multifamily commelinoid orders is diagnosed as monophyletic. We propose a revised Commelinidae, incorporating 4 revised superorders (Bromelianae, Commelinanae, Dasypogonanae, Arecanae) and 10 orders ((Poales, Eriocaulales, Cyperales, Typhales, Bromeliales), (Commelinales, Philydrales, Zingiberales), (Dasypogonales), (Arecales)). Morphological and anatomical characters used to define the original Commelinales and Commelinidae appear to be plesiomorphic or to reflect convergence or recurrent mutation; several characters supporting our revised classification are anatomical traits that seem relatively insulated from environmental selection pressures. The Commelinidae distal to the Arecales arose in South America, with amphiatlantic Bromeliaceae-Mayacaceae-Rapateaceae originating in the Guayana Shield. Ecological diversification involved the repeated invasion of shady, infertile, or arid microsites. The numbers of species in families of the revised Commelinidae are related partly to the extent of adaptive radiation in those families, but seem more strongly related to nonadaptive features promoting speciation, such as restricted seed dispersal (especially in forest interior groups with fleshy fruits), polyploidy, aneuploidy, and apomixis. Species diversity is unrelated to the rate/amount of rbcL sequence evolution.


Assuntos
Evolução Molecular , Filogenia , Plantas/genética , Ribulose-Bifosfato Carboxilase , DNA de Plantas/química , DNA de Plantas/genética , Variação Genética , Dados de Sequência Molecular , Proteínas de Plantas/genética , Plantas/anatomia & histologia , Plantas/classificação , Alinhamento de Sequência , Análise de Sequência de DNA
16.
Braz. j. med. biol. res ; 31(3): 417-20, Mar. 1998. graf
Artigo em Inglês | LILACS | ID: lil-212278

RESUMO

Drugs which influence 5-HTergic mechanisms can modify neuroleptic-induced catalepsy (NC) in rodents, a phenomenon produced by striatal dopamine (DA) receptor blockade. Previous research also suggests a role for endogenous nitric oxide (NO) in the modulation of striatal DAergic neurotransmission; in addition, NO seems to play a role in the 5-HT reuptake mechanism. It is known that clomipramine potentiates NC in mice, but the reported effects of selective 5-HT reuptake inhibitors(SSRIs) in this model are rather contradictory. We then decided to re-address this issue, investigating the effect of fluoxetine (FX), an SSRI, on NC. In view of the ubiquitous role of NO as a central neuromodulator, we also studied the effect of isosorbide dinitrate (ID), a centrally active NO donor, and how both drugs interact to effect the phenomenon of NC. Catalepsy was induced in male albino mice with haloperidol (H; 1 mg/kg, ip) and measured at 30-min interval by means of a bar test. Drugs (FX, ID and FX + ID) or saline (controls) were injected ip 30 min before H, with each animal used only once. FX (5 mg/kg) significantly reduced NC, with maximal attenuation (about 74 percent) occurring at 150 min after H. ID (5 mg/kg) also inhibited NC (150 min: 62 percent attenuation). The combined drugs (FX + ID group), however caused a great potentiation of NC (4.7-fold at its maximum, at 90 min). The effect observed with ID is compatible with the hypothesis that NO increases DA release in the striatum. The attenuation of NC observed with FX may be due to a preferential net effect oon the raphe somatodendritic synapse, where inhibitory 5-HT(1A) autoreceptors are operative. The enhancement of NC caused by combined administration of FX and ID suggests the presence of a pharmacodynamic interaction, whose mechanism, still unclear, may be related to a decrease in striatal DA release.


Assuntos
Animais , Masculino , Catalepsia/induzido quimicamente , Corpo Estriado/efeitos dos fármacos , Fluoxetina/farmacologia , Dinitrato de Isossorbida/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Vasodilatadores/farmacologia , Combinação de Medicamentos , Interações Medicamentosas , Camundongos , Fatores de Tempo
17.
Planej Agora ; 9(241): 9, 1993 Nov.
Artigo em Português | MEDLINE | ID: mdl-12346085

RESUMO

PIP: A first-page picture of the journal O Estado de S. Paulo on October, 1993, depicts 3 children playing in the ruins of a school building in Bahia. They are dressed in rags, just like the immense majority of children begotten in recent years. They are disgracefully filthy, with dishevelled hair, in the company of a pig content to share its habitat with such animalistic beings. In the inside pages of the same edition are profuse photos of other pigs dressed in suits and ties. This ostentation mocks the people and mainly the 3 children who do not attend school because the money for it has been embezzled from their pockets. Decent journalists, conscious of these piggish humans, endeavor every day to make this country a decent place to live. In the fight for a dignified and decent country, the journal Planejamento Agora, edited by ABEPF, makes an important statement with its slogan that the fight is true when the spirit is unabated. Planejamento Agora stoically battles to make every animal child alive today a human child who is wanted. The work and team of Planejamento Agora are saluted, and they are urged to continue the struggle on behalf of such children.^ieng


Assuntos
Estudos de Avaliação como Assunto , Planejamento em Saúde , Pobreza , América , Brasil , Países em Desenvolvimento , Economia , Serviços de Planejamento Familiar , América Latina , Fatores Socioeconômicos , América do Sul
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