12 research outputs found
An Image-Analysis-Based Method for the Prediction of Recombinant Protein Fiber Tensile Strength
Silk fibers derived from the cocoon of silk moths and the wide range of silks produced by spiders exhibit an array of features, such as extraordinary tensile strength, elasticity, and adhesive properties. The functional features and mechanical properties can be derived from the structural composition and organization of the silk fibers. Artificial recombinant protein fibers based on engineered spider silk proteins have been successfully made previously and represent a promising way towards the large-scale production of fibers with predesigned features. However, for the production and use of protein fibers, there is a need for reliable objective quality control procedures that could be automated and that do not destroy the fibers in the process. Furthermore, there is still a lack of understanding the specifics of how the structural composition and organization relate to the ultimate function of silk-like fibers. In this study, we develop a new method for the categorization of protein fibers that enabled a highly accurate prediction of fiber tensile strength. Based on the use of a common light microscope equipped with polarizers together with image analysis for the precise determination of fiber morphology and optical properties, this represents an easy-to-use, objective non-destructive quality control process for protein fiber manufacturing and provides further insights into the link between the supramolecular organization and mechanical functionality of protein fibers
Resource Selection and Its Implications for Wide-Ranging Mammals of the Brazilian Cerrado
Conserving animals beyond protected areas is critical because even the largest reserves may be too small to maintain viable populations for many wide-ranging species. Identification of landscape features that will promote persistence of a diverse array of species is a high priority, particularly, for protected areas that reside in regions of otherwise extensive habitat loss. This is the case for Emas National Park, a small but important protected area located in the Brazilian Cerrado, the world's most biologically diverse savanna. Emas Park is a large-mammal global conservation priority area but is too small to protect wide-ranging mammals for the long-term and conserving these populations will depend on the landscape surrounding the park. We employed novel, noninvasive methods to determine the relative importance of resources found within the park, as well as identify landscape features that promote persistence of wide-ranging mammals outside reserve borders. We used scat detection dogs to survey for five large mammals of conservation concern: giant armadillo (Priodontes maximus), giant anteater (Myrmecophaga tridactyla), maned wolf (Chrysocyon brachyurus), jaguar (Panthera onca), and puma (Puma concolor). We estimated resource selection probability functions for each species from 1,572 scat locations and 434 giant armadillo burrow locations. Results indicate that giant armadillos and jaguars are highly selective of natural habitats, which makes both species sensitive to landscape change from agricultural development. Due to the high amount of such development outside of the Emas Park boundary, the park provides rare resource conditions that are particularly important for these two species. We also reveal that both woodland and forest vegetation remnants enable use of the agricultural landscape as a whole for maned wolves, pumas, and giant anteaters. We identify those features and their landscape compositions that should be prioritized for conservation, arguing that a multi-faceted approach is required to protect these species
Translocation and radiotelemetry monitoring of black-tailed marmosets, Callithrix (Mico) melanura(É. Geoffroy in Humboldt), in a wildlife rescue operation in Brazil
Five black-tailed marmoset Callithrix (Mico) melanura (Primates - Callitrichidae) individuals were monitored by radiotelemetry as part of a project on translocated wildlife affected by flooding the Manso River reservoir in the state of Mato Grosso, western Brazil (14° 52' S and 55° 48' W). The animals were monitored for eight months from October 2000 through August 2001. Only one death was recorded among the translocated animals. Two pairs established their home ranges in the new area, after some exploratory behavior. The new home range sizes varied from 0.72 to 4.27 km². The home ranges of male and female overlapped in the case of both pairs by 0.59 to 2.30 km². Trips were always made in pairs and not individually. The results indicate the feasibility of a successful translocation program for this species, as long as the animals are translocated to a similar habitat nearby