8 research outputs found
Simulations of populations of Sapajus robustus in a fragmentedlandscape.
The study of populations subject to the phenomenon of loss and fragmentation of habitat, transformingcontinuous areas into small ones, usually surrounded by anthropogenic matrices, has been the focus ofmany researches within the scope of conservation. The objective of this study was to develop a com-puter model by introducing modifications to the renowned Penna model for biological aging, in order toevaluate the behavior of populations subjected to the effects of fragmented environments. As an objectof study, it was used biological data of the robust tufted capuchin (Sapajus robustus), an endangered pri-mate species whose geographical distribution within the Atlantic Rain Forest is part of the backdrop ofintense habitat fragmentation. The simulations showed the expected behavior based on the three mainaspects that affects populations under intense habitat fragmentation: the population density, area andconformation of the fragments and deleterious effects due the low genetic variability in small and isolatedpopulations. The model showed itself suitable to describe changes in viability and population dynamicsof the species crested capuchin considering critical levels of survival in a fragmented environment andalso, actions in order to preserve the species should be focused not only on increasing available area butalso in dispersion dynamic
Evaluation of the losartan solubility in the biowaiver context by shake-flask method and intrinsic dissolution.
This study aimed at evaluating the shake-flask use as a universal method to evaluate drug solubility in a biowaiver context as proposed by FDA, EMA and ANVISA. The solubility of losartan was determined in three buffers using the shake-flask method, intrinsic dissolution (ID) and Quantum Chemistry. Moreover, the evaluation of a losartan dissolution profile from coated tablets was conducted. The losartan low solubility in pH 1.2 and high solubility in pH 6.8 were observed using the shake-flask method. However, the solubility results using ID demonstrated its high solubility in pH 1.2 and 6.8. It was not possible to find conclusive results regarding the solubility of the drug in pH 4.5. The studies conducted by Quantum Chemistry provide molecular and electronic data that helped understand the losartan solvation in different pH values. Our experimental results defined that losartan can be classified as a low-solubility drug. In addition, this work shows that shake-flask cannot be a universal method of solubility studies in biowaiver context. Individual analysis will be necessary. The intrinsic dissolution should be considered as a complementary method
Structure and distribution of glandular trichomes in three species of Bignoniaceae
Glandular trichomes play a major role in the morphological characterization of the Bignoniaceae. Due to their great diversity of forms and functions, this study aimed to inventory the glandular trichomes present in the aerial vegetative axis of Amphilophium magnoliifolium, Martinella obovata and Stizophyllum riparium, analyze their structure and register the participation of ants in these plants. Fresh samples from the nodal region, petiole and from medium to apical regions of the leaflet blade were fixed and processed according to usual methods in light and scanning electron microscopies. The glandular trichomes found were: peltate, capitate, stipitate, and patelliform/cupular. Peltate trichomes are the most abundant ones and present the most uniform distribution. Patelliform/cupular trichomes occur at specific regions, such as prophylls, leaflet blade and nodal regions. Martinella obovata is the only species that presents capitate and stipitate trichomes, which are widely distributed along the entire aerial vegetative axis. Ants were found in all species, mainly at nodal regions. The occurrence of the capitate-type trichome is reported for the first time to the genus
Growth performance, carcass traits and meat quality of lambs fed increasing level of Macadamia nut cake
The sensitivity of Demodex canis (Acari: Demodicidae) to the essential oil of Melaleuca alternifolia – an in vitro study
Performance of the Santa Ines breed raised on pasture in semiarid tropical regions and factors that explain trait variation
Global effects of land use on local terrestrial biodiversity
Human activities, especially conversion and degradation of habitats, are causing global biodiversity declines. How local ecological assemblages are responding is less clear--a concern given their importance for many ecosystem functions and services. We analysed a terrestrial assemblage database of unprecedented geographic and taxonomic coverage to quantify local biodiversity responses to land use and related changes. Here we show that in the worst-affected habitats, these pressures reduce within-sample species richness by an average of 76.5%, total abundance by 39.5% and rarefaction-based richness by 40.3%. We estimate that, globally, these pressures have already slightly reduced average within-sample richness (by 13.6%), total abundance (10.7%) and rarefaction-based richness (8.1%), with changes showing marked spatial variation. Rapid further losses are predicted under a business-as-usual land-use scenario; within-sample richness is projected to fall by a further 3.4% globally by 2100, with losses concentrated in biodiverse but economically poor countries. Strong mitigation can deliver much more positive biodiversity changes (up to a 1.9% average increase) that are less strongly related to countries' socioeconomic status