Resultados da pesquisa - "Negreiros, J."

Catálogo de Publicações - "Negreiros, J."

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  1. 1

    Spatial Autocorrelation and Association Measures

    Publicação
    por Negreiros, J.
    Outros Autores: Painho, Marco; Lopes, I.; Costa, A. C.
    Several classical statements relating to the definition of GIS can be found in specialized literature such as the GIS International Journal, expressing the idea that spatial analysis can somehow be useful. GIS is successful not only because it integrates data, but it also enables us to share data in different departments or segments of our organizations. I like this notion of putting the world’s pieces back together again (ArcNews, 2000). “GIS is simultaneously the telescope, the microscope, the computer and the Xerox machine of regional analysis and the synthesis of spatial data” (Abler, 1988). “GIS is a system of hardware, software and liveware implemented with the aim of storing, processing, visualizing and analyzing data of a spatial nature. Other definitions are also possible” (Painho, 1999). “GIS is a tool for revealing what is otherwise invisible in geographical information” (Longley, Goodchild, Maguire, & Rhind, 2001). Certainly, GIS is not a graphic database.
    2008 capítulo de livro Portugal acesso aberto
  2. 2

    Spatial neighborhood matrix computation: Inverse distance weighted versus binary contiguity

    Publicação
    por Negreiros, J
    A particular GIS aspect is the existence of the spatial neighborhood weighted matrix (W) needed for their assessment and commonly setup by the binary or inverse distance weight (IDW)contiguity. This article recommends that if the former approach fulfills W specification quite well, the distance decay contiguity of IDW, by itself, is blinded to its natural neighbors because the exponent of 1/dexp already underlies the considered number of neighbors. In a more wise approach, IDW should be used mutually with the binary one.
    2009 documento de conferência Portugal acesso aberto
  3. 3

    Risk assessment

    Publicação
    por Negreiros, J.
    Outros Autores: Painho, Marco; Aguilar, M.; Aguilar, F.
    SAKWeb
    2010 documento de conferência Portugal acesso aberto
  4. 4

    The local confidence uncertainty plume of SAKWeb

    Publicação
    por Negreiros, J.
    Outros Autores: Painho, Marco; Costa, Ana Cristina; Cabral, Pedro; Aguilar, F.
    The main goal of this research paper is to introduce a new uncertainty tool based on the Moran I correlogram, rescaled OK variance and local variance in a Web environment. It is hoped that this implementation will be used by users with problems to layout risk analysis environmental maps and plumes assessment. Spatial analysis, Moran I and other uncertainty measures are also reviewed.
    2008 documento de conferência Portugal acesso aberto
  5. 5

    The nugget-effect approaches of SAKWeb for environmental modelling

    Publicação
    por Negreiros, J.
    Outros Autores: Painho, Marco; Costa, Ana Cristina; Cabral, Pedro; Oliveira, Tiago
    Ordinary Kriging (OK) seems to achieve better spatial interpolation results than other methods regarding environmental pollution, for instance, although sampling distribution can turn out to be a problem. This latter issue leads to a crucial topic identified as the nugget-effect, the distance interval in which capturing spatial dependency is most important. SAKWeb© developments have been made using four approaches to this factor: (1) with and (2) without nugget-effect, (3) micro-scale component and (4) measurement error inclusion that leads to a non-exact Kriging version. Although no spatial patterns can be found regarding which nugget-effect fits best, the possibility of simulating different on-the-fly models and comparing discrepancy among them is already significant in a W3 context.
    2008 documento de conferência Portugal acesso aberto
  6. 6

    Yield of essential oil and safrole content based on fresh and dry biomass of long pepper in the Brazilian Amazon.

    Publicação
    por NEGREIROS, J. R. da S.
    Outros Autores: MIQUELONI, D. P.; CARTAXO, C. B. da C.
    Origem: Oasisbr
    Long pepper (Piper hispidinervum) is an Amazonian species of commercial interest due to the production of safrole. Drying long pepper biomass to extract safrole is a time consuming and costly process that can also result in the contamination of the material by microorganisms. The objective of this study was to analyze the yield of essential oil and safrole content of fresh and dried biomass of long pepper accessions maintained in the Active Germoplasm Bank of Embrapa Acre, in the state of Acre, Brazil, aiming at selecting genotypes with best performance on fresh biomass to recommend to the breeding program of the species. Yield of essential oil and safrole content were assessed in 15 long pepper accessions. The essential oil extraction was performed by hydrodistillation and analyzed by gas chromatography. A joint analysis of experiments was performed and the means of essential oil yield and safrole content for each biomass were compared by Student's t-test. There was variability in the essential oil yield and safrole content. There was no difference between the types of biomass for oil yield; however to the safrole content there was difference. Populations 9, 10, 12 and 15 had values of oil yield between 4.1 and 5.3%, and safrole content between 87.2 and 94.3%. The drying process does not interfere in oil productivity. These populations have potential for selection to the long pepper breeding program using oil extraction in the fresh biomass.
    2015 artigo Brasil acesso aberto
  7. 7

    Morphological and phytochemical characterization of Piper hispidinervum DC. and Piper aduncum L. populations in the state of Acre.

    Publicação
    por NEGREIROS, J. R. da S.
    Outros Autores: NIQUELONI, D. P.
    Origem: Oasisbr
    Because of the increasing demand of the industry for the production of essential oils, studies highlight the genetic variability of Piper hispidinervum and P. aduncum species according to their patterns of spatial distribution, showing the Amazon region as the source of superior genetic material in the production of safrole and dillapiole. Thus, the objective this study was to characterize the morphology and the phytochemistry of Piper hispidinervum and P. aduncum populations in the Active Germplasm Bank of Embrapa Acre to generate subsidies for the genetic improvement of these species. The results showed that the average values for leaf width and length were 141.67 and 48.04 mm, and petioles length and diameter measurements were 2.83 and 1.78 mm for P. hispidinervum and 189.22; 67.74; 6.03 and 2.22 mm for P. aduncum respectively. The average height and canopy volume measurements were 2.39 m and 6.30 m3 and 2.70 m and 7.78 m3 respectively for each species. For P. hispidinervum, the population with higher performance indried yield and content of safrole was population 02, with 3.9%, and the population 04 showed 94.3% safrole content, both with genetic material from the region of Acrelândia and Plácido de Castro. To P. aduncum, the populations with better performance were 207, 208 and 209, forming a homogeneous group with dried yield average of 3.8% and dillapiol content of 84-85%. Such populations are indicated for selection in breeding program of these species due to better performance.
    2016 artigo Brasil acesso aberto
  8. 8

    Lipid peroxidation and seed emergency in progenies of the yellow passion fruit plant.

    Publicação
    por OLIVEIRA, J. P. B. de
    Outros Autores: ALEXANDRE, R. S.; NEGREIROS, J. R. da S.; LOPES, J. C.; BRUCKNER, C. H.
    Origem: Oasisbr
    The objective was to evaluate the percentage of emergency plantlets and lipid peroxidation in seeds of 29 half-sib progenies of yellow passion fruit (Passiflora edulis Sims.) after 24 months under storage. The experimental design was completely randomized, with four replications of 50 seeds each, from which the treatments were the progenies (1-29). The evaluation of the percent plantlet emergency was accomplished at 14 and 28 days after sowing. The lipid peroxidation of the seeds was expressed as malondialdehyde (MDA) content that was determined by the TBARS method. Approximately 21% of those half-sib progenies maintained the viability of their seeds for twenty-four months under storage. The results point out a remarkable genetic variability for vigor and emergency of the yellow passion fruit plantlets, with occurrence of individuals with high and other ones with low capacity to maintaining the physiologic quality of their seeds after storage.
    2012 artigo Brasil acesso aberto
  9. 9

    Influence of postharvest water replacement on shelf life of parsley leaves.

    Publicação
    por FINGER, F. L.
    Outros Autores: ALVARES, V. de S.; NEGREIROS, J. R. da S.; CALESTINE, C.; CASALI, V. W. D.
    Origem: Oasisbr
    Wilting is one of the major problems of parsley leaves in Brazilian retail stores. This study was conducted to determine the effect of postharvest replacement of water by submerging the parsley leaf bunches in water for 3, 6 or 9 hours at three stages: when total weight loss reached 5 and 10% and immediately after two hours of storage. Leaves were stored at 5 or 25ºC until visible wilting or yellowing was detected. Results demonstrated that water replacement resulted in gains in fresh mass, resulting in longer shelf life for leaves stored at 5 and 25ºC. In general, longer recharging resulted in greater water uptake by the leaves, but at a lower rate. By recharging the leaves with water, lower rates of mass loss were observed compared to untreated leaf bunches. Regardless the storage temperature, the relative water content of leaves decreased during shelf life, which in general was less accentuated for leaves submerged in water for 6 and 9 hours. Postharvest water replacement should be considered as an option to extend the shelf life of horticultural products that are susceptible to intense moisture loss.
    2011 artigo Brasil acesso aberto
  10. 10

    Germination and vigor of long-pepper seeds (Piper hispidinervum) as a function of temperature and light.

    Publicação
    por PACHECO JUNIOR, F.
    Outros Autores: SILVA, J. B. da; NEGREIROS, J. R. da S.; SILVA, M. R. G. da; FARIAS, S. B.
    Origem: Oasisbr
    A pimenta longa é considerada uma espécie promissora por apresentar a perspectiva de tornar o Brasil autosuficiente na produção de safrol, importante óleo essencial usado como fixador de fragrâncias e com propriedades terapêuticas. Na implantação de áreas destinadas à cultura dessa espécie é necessário avaliar a qualidade fisiológica das sementes utilizadas na formação de mudas. O objetivo foi determinar as condições de temperatura e luminosidade para o teste de germinação e vigor em sementes de pimenta longa. Foram utilizadas sementes de quatro lotes para as seguintes determinações: teor de água (105 + 3 ºC por 24 horas), germinação (20; 25; 30 e 35 °C com fotoperíodo de 12 e 24 horas, e alternadas de 20-30 °C e 20-35 °C, com 12 horas de luz na temperatura mais alta), índice de velocidade de germinação, velocidade de germinação, matéria seca de plântulas, emergência de plântulas, índice de velocidade de emergência e freqüência relativa da germinação. O delineamento experimental foi o inteiramente casualizado e as médias comparadas por Tukey (P<0,05). A germinação de sementes de pimenta longa pode ser avaliada a 25 °C/12 h escuro - 12 h luz, 25 °C/24 h luz, 30 °C/12 h escuro - 12 h luz e 30 °C/24 h luz, e o potencial fisiológico a 30 °C/24 h luz.
    2013 artigo Brasil acesso aberto