Detection of alfa-amylase inhibitors by a zymography method, performed in isoelectric focusing electrophoretic PhastGels.

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Biological activity of poriferans extracts from the Colombian Caribbean on Meloidogyne incognita and Spodoptera frugiperda IPLB-SF-21 cell line.

Sinconbiol

Digestive alfa-amylases from Tecia solanivora larvae (Lepidoptera: Gelechiidae): response to pH, temperature and plant amylase inhibitors.

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Determination of plasma frequency, damping constant, and size distribution from the complex dielectric function of noble metal nanoparticles

This paper develops a novel method for simultaneously determining the plasma frequency ωP  ωP   and the damping constant γfreeγfree in the bulk damped oscillator Drude model, based on experimentally measured real and imaginary parts of the metal refractive index in the IR wavelength range, lifting the usual approximation that restricts frequency values to the UV-deep UV region. Our method was applied to gold, silver, and copper, improving the relative uncertainties in the final values for ωpωp (0.5%–1.6%) and for γfreeγfree (3%–8%), which are smaller than those reported in the literature. These small uncertainties in ωpωp and γfreeγfree determination yield a much better fit of the experimental complex dielectric function. For the case of nanoparticles (Nps), a series expansion of the Drude expression (which includes ωpωp and γfreeγfree determined using our method) enables size-dependent dielectric function to be written as the sum of three terms: the experimental bulk dielectric function plus two size corrective terms, one for free electron, and the other for bound-electron contributions. Finally, size distribution of nanometric and subnanometric gold Nps in colloidal suspension was determined through fitting its experimental optical extinction spectrum using Mie theory based on the previously determined dielectric function. Results are compared with size histogram obtained from Transmission Electron Microscopy (TEM).Fil: Mendoza Herrera, Luis Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones Opticas (i); Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Muñetón Arboleda, David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones Opticas (i); Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Schinca, Daniel C.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones Opticas (i); Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ingenieria; ArgentinaFil: Scaffardi, Lucia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones Opticas (i); Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentin

Human chromosome 11 contains two different growth suppressor genes for embryonal rhabdomyosarcoma.

The identification of acquired homozygosity in human cancers implies locations of tumor suppressor genes without providing functional evidence. The localization of a defect in embryonal rhabdomyosarcomas to chromosomal region 11p15 provides one such example. In this report, we show that transfer of a normal human chromosome 11 into an embryonal rhabdomyosarcoma cell line elicited a dramatic loss of the proliferative capacity of the transferrants. Indeed, the majority of the viable microcell hybrids had either eliminated genetic information on the short arm of the transferred chromosome 11 or increased the copy number of the rhabdomyosarcoma-derived chromosomes 11. Cells that possessed only the long arm of chromosome 11 also demonstrated a decreased growth rate. In contrast, all microcell hybrids retained the ability to form tumors upon inoculation into animals. These functional data support molecular studies indicating loss of genetic information on chromosome 11p15 during the development of embryonal rhabdomyosarcoma. In addition, our studies demonstrate the existence of a second gene on the long arm, previously unrecognized by molecular analyses, which negatively regulates the growth of embryonal rhabdomyosarcoma cell lines

Geologising urban political ecology (UPE): the urbanisation of sand in Accra, Ghana

This paper makes a call for an urban political ecology (UPE) which engages more extensively with Earth’s geological formations. As a material at the centre of global urbanisation process, sand is offered as a geological entry point. The paper presents an analysis of the urbanisation of sand, or the ways in which sand is brought into the urban realm, grounding this reading in Accra—a growing city on Ghana’s Atlantic coast. Drawing from 14 months of ethnographic fieldwork, the paper charts the socio-natural politics through which sand is first unearthed from the edges of the city—an extractive processes otherwise known as “sand winning” in Ghana. By examining the forms of power which govern uneven revenue flows to communities, the displacement of farming groups, the widespread loss of farmland and a contested regime of governance, the analysis exposes the socio-natural politics through which the city’s geological baseline is first unearthed

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors

Geography and ecology shape the phylogenetic composition of Amazonian tree communities.

Aim Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location Amazonia. Taxon Angiosperms (Magnoliids; Monocots; Eudicots). Methods Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.Na publicação: Joice Ferreira