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1.
Genet Mol Res ; 16(2)2017 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-28510252

RESUMEN

Understanding non-additive effects in the expression of quantitative traits is very important in genotype selection, especially in species where the commercial products are clones or hybrids. The use of molecular markers has allowed the study of non-additive genetic effects on a genomic level, in addition to a better understanding of its importance in quantitative traits. Thus, the purpose of this study was to evaluate the behavior of the GBLUP model in different genetic models and relationship matrices and their influence on the estimates of genetic parameters. We used real data of the circumference at breast height in Eucalyptus spp and simulated data from a population of F2. Three commonly reported kinship structures in the literature were adopted. The simulation results showed that the inclusion of epistatic kinship improved prediction estimates of genomic breeding values. However, the non-additive effects were not accurately recovered. The Fisher information matrix for real dataset showed high collinearity in estimates of additive, dominant, and epistatic variance, causing no gain in the prediction of the unobserved data and convergence problems. Estimates presented differences of genetic parameters and correlations considering the different kinship structures. Our results show that the inclusion of non-additive effects can improve the predictive ability or even the prediction of additive effects. However, the high distortions observed in the variance estimates when the Hardy-Weinberg equilibrium assumption is violated due to the presence of selection or inbreeding can converge at zero gains in models that consider epistasis in genomic kinship.


Asunto(s)
Eucalyptus/genética , Modelos Genéticos , Carácter Cuantitativo Heredable , Epistasis Genética , Eucalyptus/crecimiento & desarrollo , Genotipo
2.
Science ; 355(6328): 925-931, 2017 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-28254935

RESUMEN

The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by pre-Columbian peoples. Domesticated species are five times more likely than nondomesticated species to be hyperdominant. Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites. In southwestern and eastern Amazonia, distance to archaeological sites strongly influences the relative abundance and richness of domesticated species. Our analyses indicate that modern tree communities in Amazonia are structured to an important extent by a long history of plant domestication by Amazonian peoples.


Asunto(s)
Domesticación , Bosques , Árboles , Brasil , Historia Antigua , Humanos
3.
Braz. j. biol ; 76(4): 912-927, Oct.-Dec. 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-828105

RESUMEN

Abstract The goal of this study is to analyze the floristic patterns and the structure of disturbed and undisturbed upland forests, in Permanent Preservation Areas (PPAs) along the Moju river, in the Brazilian state of Pará. Trees with a diameter equal to or larger than 10cm at 1.30m from the ground (DBH) ≥10cm were analyzed for the upper stratum. For the middle stratum, individuals with DBH between 4.99 and 9.99cm were sampled. Forty-five families and 221 species were found in disturbed forests, and 43 families and 208 species in undisturbed forests. Floristic similarity was high between strata and between forest types, with values above 50%. Similarity was highest between middle strata. The most species-abundant families in undisturbed forests were Fabaceae, Sapotaceae, Chrysobalanaceae and Myrtaceae; the species with the highest density there were Eschweilera grandiflora, Licania sclerophylla and Zygia cauliflora. In disturbed forests, the dominant families were Fabaceae, Sapotaceae, Lecythidaceae and Melastomataceae. The Shannon-Wiener diversity index was 3.21 for undisturbed forests and 2.85 for disturbed forests. Non-metric multidimensional scaling (MDS) analysis did not group the forests by their floristic composition in both upper and middle strata. Overall, the PPA forests along the Moju river, even if disturbed, did not show major floristic changes but substantially change their structural characteristics.


Resumo Este estudo teve como objetivo analisar os padrões florísticos e a estrutura de florestas ripárias perturbadas e não perturbadas inseridas em Áreas de Preservação Permanente ao longo do rio Moju, Pará. A análise do estrato superior foi realizada em árvores com diâmetro a 1,30 m do solo (DAP) ≥10 cm. No estrato médio, amostrou-se os indivíduos com DAP entre 4,99 e 9,99 cm DAP. Nas florestas perturbadas foram encontradas 45 famílias e 221 espécies e nas florestas não perturbadas, 43 famílias e 208 espécies. A similaridade florística foi elevada entre os estratos e entre os tipos de florestas, alcançando valores maiores de que 50%. A maior semelhança foi encontrada entre os estratos médios. As famílias mais abundantes em espécies nas florestas não perturbadas foram Fabaceae, Sapotaceae, Chrysobalanaceae e Myrtaceae. As espécies com maiores densidades foram Eschweilera grandiflora, Licania sclerophylla e Zygia cauliflora. Nas florestas perturbadas, as famílias dominantes foram Fabaceae, Sapotaceae, Lecythidaceae e Melastomataceae. A diversidade (Shannon) nas florestas não perturbadas foi de 3,21, e nas florestas perturbadas, alcançaram 2,85. A ordenação feita pelo escalonamento multidimensional MDS, não agrupou as florestas por sua composição florística, tanto no estrato superior como no médio. Em geral, as florestas perturbadas das APPs do rio Moju, mesmo se perturbadas, não evidenciam grandes mudanças florísticas, mas apresentam alterações nas suas características estruturais.


Asunto(s)
Árboles , Bosques , Conservación de los Recursos Naturales , Biodiversidad , Brasil , Ríos
4.
Braz J Biol ; 76(4): 912-927, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27191459

RESUMEN

The goal of this study is to analyze the floristic patterns and the structure of disturbed and undisturbed upland forests, in Permanent Preservation Areas (PPAs) along the Moju river, in the Brazilian state of Pará. Trees with a diameter equal to or larger than 10cm at 1.30m from the ground (DBH) ≥10cm were analyzed for the upper stratum. For the middle stratum, individuals with DBH between 4.99 and 9.99cm were sampled. Forty-five families and 221 species were found in disturbed forests, and 43 families and 208 species in undisturbed forests. Floristic similarity was high between strata and between forest types, with values above 50%. Similarity was highest between middle strata. The most species-abundant families in undisturbed forests were Fabaceae, Sapotaceae, Chrysobalanaceae and Myrtaceae; the species with the highest density there were Eschweilera grandiflora, Licania sclerophylla and Zygia cauliflora. In disturbed forests, the dominant families were Fabaceae, Sapotaceae, Lecythidaceae and Melastomataceae. The Shannon-Wiener diversity index was 3.21 for undisturbed forests and 2.85 for disturbed forests. Non-metric multidimensional scaling (MDS) analysis did not group the forests by their floristic composition in both upper and middle strata. Overall, the PPA forests along the Moju river, even if disturbed, did not show major floristic changes but substantially change their structural characteristics.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Bosques , Árboles , Brasil , Ríos
5.
Braz J Biol ; 72(2): 257-65, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22735132

RESUMEN

This study aims to identify the remnant tree flora in six forest fragments in the metropolitan area of Belém and to analyze these fragments in terms of biological conservation, species richness and diversity in the local urban landscape. The fragments and their respective sampling areas were as follows: Amafrutas reserve (15 ha), Trambioca Is. reserve (2 ha), Bosque Rodrigues Alves city park (15 ha), Combu Is. reserve (10 ha), Gunma Park reserve (10 ha) and Mocambo reserve (5 ha). Inventories were built from lineal plots of 250 m² and included trees with DBH equal to or greater than 10 cm at a height of 1.3 m above ground. Sixty-nine families and 759 species, of which eight were officially listed as endangered (Brazilian National Flora: Ministry of Environment, Normative Instruction of September, 2008; Pará State Flora: Decree Nº. 802 of February 2008) were recorded. These endangered species are: Aspidosperma desmanthum Benth. ex Müll. Arg. (Apocynaceae), Cedrela odorata L. (Meliaceae), Eschweilera piresii S.A Mori (Lecythidaceae), Euxylophora paraensis Huber (Rutaceae), Hymenolobium excelsum Ducke (Leguminosae), Manilkara huberi (Ducke) Chevalier (Sapotaceae), Tabebuia impetiginosa (Mart. ex DC.) Standl. (Bignoniaceae), Mezilaurus itauba (Meisn.) Taub. ex Mez (Lauraceae) and Qualea coerulea Aubl. (Vochysiaceae). Emergency actions such as implementing management plans for already existing Conservation Units, the creation of new such units in areas of primary forest fragments (as in the case of the Amafrutas reserve), as well as the intensification of actions of surveillance and monitoring, should be undertaken by Federal, State, and Municipal environmental agencies so as to ensure the conservation of these last primary forest remnants in the metropolitan area of Belém.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Árboles/clasificación , Brasil
6.
Braz. j. biol ; 68(4,supl): 949-956, Nov. 2008.
Artículo en Inglés | LILACS | ID: lil-504449

RESUMEN

This is a review of the main factors currently perceived as threats to the biodiversity of Amazonia. Deforestation and the expansion of the agricultural frontier go hand in hand within the context of occupation and land use in the region, followed by a hasty process of industrialization since the 1950s and, more recently, by a nation-wide attempt to adapt Brazil to economic globalization. Intensive agriculture and cattle-raising, lack of territorial planning, the monoculture of certain crops often promoted by official agencies, and the introduction of exotic species by cultivation are some of the factors affecting Amazonian biodiversity. There are still large gaps in knowledge that need to be dealt with for a better understanding of the local ecosystems so as to allow their preservation, but such investigation is subjected to manifold hindrances by misinformation, disinformation and sheer ignorance from the legal authorities and influential media. Data available for select groups of organisms indicate that the magnitude of the loss and waste of natural resources associated with deforestation is staggering, with estimated numbers of lost birds and primates being over ten times that of such animals illegally commercialized around the world in one year. The challenges to be met for an eventual reversal of this situation demand more systematic and concerted studies, the consolidation of new and existing research groups, and a call for a halt to activities depleting the Amazonian rainforest.


Este trabalho mostra um panorama dos principais fatores hoje percebidos como ameaças à biodiversidade na Amazônia. O desmatamento e a expansão da fronteira agrícola caminham lado a lado dentro do contexto da ocupação e do uso da terra na região, seguidos de um processo acelerado de industrialização desde a década de 1950 e, mas recentemente, de tentativas em escala nacional para adaptar o Brasil à globalização econômica. Agricultura e pecuária intensiva, a falta de ordenamento territorial, a monocultura de certas espécies e a introdução de espécies exóticas para cultivo são alguns dos fatores que afetam a biodiversidade da Amazônia. Ainda há grandes lacunas de conhecimento que precisam ser resolvidas para o melhor conhecimento dos ecossistemas locais de modo a possibilitar sua preservação, mas essa investigação anda sujeita a inúmeros empecilhos devido à desinformação, contra-informação e pura ignorância das autoridades legais e da mídia influente. Dados disponíveis para alguns grupos de organismos indicam que a magnitude da perda e desperdício de recursos naturais devida ao desmatamento é imensa, com estimativas de números de aves e primatas perdidos da ordem de mais de dez vezes maior que as desses animais comercializados ilegalmente em um ano em todo o mundo. Os desafios necessários a uma eventual reversão desse quadro exigem estudos mais sistemáticos e coordenados, a consolidação de grupos de pesquisa novos e já existentes, e um apelo para a cessação das atividades que exaurem a Floresta Amazônica.


Asunto(s)
Animales , Bovinos , Humanos , Biodiversidad , Conservación de los Recursos Naturales , Árboles , Agricultura , Crianza de Animales Domésticos/métodos , Brasil , Conservación de los Recursos Naturales/tendencias , Dinámica Poblacional , Medición de Riesgo , América del Sur , Clima Tropical
7.
Braz J Biol ; 68(4 Suppl): 949-56, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19197467

RESUMEN

This is a review of the main factors currently perceived as threats to the biodiversity of Amazonia. Deforestation and the expansion of the agricultural frontier go hand in hand within the context of occupation and land use in the region, followed by a hasty process of industrialization since the 1950s and, more recently, by a nation-wide attempt to adapt Brazil to economic globalization. Intensive agriculture and cattle-raising, lack of territorial planning, the monoculture of certain crops often promoted by official agencies, and the introduction of exotic species by cultivation are some of the factors affecting Amazonian biodiversity. There are still large gaps in knowledge that need to be dealt with for a better understanding of the local ecosystems so as to allow their preservation, but such investigation is subjected to manifold hindrances by misinformation, disinformation and sheer ignorance from the legal authorities and influential media. Data available for select groups of organisms indicate that the magnitude of the loss and waste of natural resources associated with deforestation is staggering, with estimated numbers of lost birds and primates being over ten times that of such animals illegally commercialized around the world in one year. The challenges to be met for an eventual reversal of this situation demand more systematic and concerted studies, the consolidation of new and existing research groups, and a call for a halt to activities depleting the Amazonian rainforest.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Árboles , Agricultura , Crianza de Animales Domésticos/métodos , Animales , Brasil , Bovinos , Conservación de los Recursos Naturales/tendencias , Humanos , Dinámica Poblacional , Medición de Riesgo , América del Sur , Clima Tropical
8.
Am J Med Genet ; 98(3): 230-4, 2001 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-11169560

RESUMEN

We report on a family with typical clinical findings of Noonan syndrome associated with giant cell lesions in maxilla and mandible. We discuss the obvious clinical overlap between Noonan syndrome and Noonan-like/multiple giant cell lesion syndrome, and we give further clinical and molecular support that these two entities could be allelic conditions.


Asunto(s)
Granuloma de Células Gigantes/patología , Síndrome de Noonan/patología , Adolescente , Adulto , Cromosomas Humanos Par 12/genética , ADN/genética , Diagnóstico Diferencial , Salud de la Familia , Femenino , Granuloma de Células Gigantes/genética , Haplotipos , Humanos , Masculino , Repeticiones de Microsatélite , Síndrome de Noonan/genética , Linaje , Síndrome
9.
Talanta ; 55(4): 685-92, 2001 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18968415

RESUMEN

A biosensor based on vaseline/graphite modified with avocado tissue (Persea americana) as the source of polyphenol oxidase was developed and used for the chronoamperometric determination of paracetamol in pharmaceutical formulations. This enzyme catalyses the oxidation of paracetamol to N-acetyl-p-benzoquinoneimine whose electrochemical reduction back to paracetamol was obtained at a potential of -0.12 V. After addition of paracetamol reference solutions in glass cell and stirring for 60 s for the accumulation of N-acetyl-p-benzoquinoneimine at the electrode surface under open-circuit conditions, the current response was monitored by 120 s without stirring. The currents obtained at 70 s were proportional to the paracetamol concentration from 1.2x10(-4) to 5.8x10(-3) mol l(-1) (r=0.9927) with a detection limit of 8.8x10(-5) mol l(-1). The recovery of paracetamol from two samples ranged from 97.9 to 100.7% and a relative standard deviation lower than 0.5% for a solution containing 5.0x10(-3) mol l(-1) paracetamol in 0.10 mol l(-1) phosphate buffer solution (pH 7.0; n=10) was obtained. The results obtained for paracetamol in pharmaceutical formulations using the proposed biosensor and those obtained using a pharmacopoeial procedure are in agreement at the 95% confidence level.

10.
Fresenius J Anal Chem ; 368(4): 338-43, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11227501

RESUMEN

A biosensor based on stearic acid-graphite powder modified with sweet potato (Ipomoea batatas (L.) Lam.) tissue as peroxidase source was constructed and applied in organic solvents. Several parameters were studied to evaluate the performance of this biosensor such as stearic acid-graphite powder and tissue composition, type and concentration of supporting electrolyte, organic solvents, water/organic solvent ratio (% v/v) and hydrogen peroxide concentration. After selection of the best conditions, the biosensor was applied for the determination of hydroquinone in cosmetic creams in methanol. At the peroxidase electrode hydroquinone is oxidized in the presence of hydrogen peroxide and the radical formed was reduced back electrochemically at -180 mV vs Ag/AgCl (3.0 mol L(-1) KCl). The reduction current obtained was proportional to the concentration of hydroquinone from 6.2 x 10(-5) to 1.5 x 10(-3) mol L(-1) (r = 0.9990) with a detection limit of 8.5 x 10(-6) mol L(-1). The recovery of hydroquinone from two samples ranged from 98.8 to 104.1% and an RSD lower than 1.0% for a solution containing 7.3 x 10(-4) mol L(-1) hydroquinone and 1.0 x 10(-3) mol L(-1) hydrogen peroxide in 0.10 mol L(-1) tetrabutylammonium bromide methanol-phosphate buffer solution (95:5% v/v) (n = 10) was obtained.


Asunto(s)
Técnicas Biosensibles/métodos , Solanaceae , Solventes/farmacología , Antioxidantes/análisis , Cosméticos/química , Cosméticos/normas , Cosméticos/toxicidad , Grafito , Hidroquinonas/análisis , Compuestos Orgánicos/farmacología , Peroxidasa , Protectores contra Radiación/análisis , Reproducibilidad de los Resultados , Solanaceae/enzimología , Ácidos Esteáricos
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