7 research outputs found
Fishers' knowledge and seahorse conservation in Brazil
From a conservationist perspective, seahorses are threatened fishes. Concomitantly, from a socioeconomic perspective, they represent a source of income to many fishing communities in developing countries. An integration between these two views requires, among other things, the recognition that seahorse fishers have knowledge and abilities that can assist the implementation of conservation strategies and of management plans for seahorses and their habitats. This paper documents the knowledge held by Brazilian fishers on the biology and ecology of the longsnout seahorse Hippocampus reidi. Its aims were to explore collaborative approaches to seahorse conservation and management in Brazil; to assess fishers' perception of seahorse biology and ecology, in the context evaluating potential management options; to increase fishers' involvement with seahorse conservation in Brazil. Data were obtained through questionnaires and interviews made during field surveys conducted in fishing villages located in the States of Piauí, Ceará, Paraíba, Maranhão, Pernambuco and Pará. We consider the following aspects as positive for the conservation of seahorses and their habitats in Brazil: fishers were willing to dialogue with researchers; although captures and/or trade of brooding seahorses occurred, most interviewees recognized the importance of reproduction to the maintenance of seahorses in the wild (and therefore of their source of income), and expressed concern over population declines; fishers associated the presence of a ventral pouch with reproduction in seahorses (regardless of them knowing which sex bears the pouch), and this may facilitate the construction of collaborative management options designed to eliminate captures of brooding specimens; fishers recognized microhabitats of importance to the maintenance of seahorse wild populations; fishers who kept seahorses in captivity tended to recognize the condtions as poor, and as being a cause of seahorse mortality
The effect of ink dilution and evaporation on the microstructures of catalyst layers in polymer electrolyte membrane fuel cells
The microstructures of catalyst layers (CLs) in proton exchange membrane fuel cells determine cell performance and durability. Delicate ink preparation processes and coating/drying processes affect the resulting microstructures including active sites, pore networks, ionomer networks and Pt/C networks. This paper reports our recent experimental observations of the effect of ink dilution and evaporation condition on the microstructures. The microstructures of dried ink droplets are presented and compared among different dilution ratios and different evaporation conditions in terms of the spatial distributions of Pt/C particles, ionomers, and pores. The method through which the microstructures are visualized is also introduced in this paper. It is observed that ink dilution ratio and evaporation condition can significantly alter resulting microstructure patterns through affecting viscosity and particle flow patterns during the evaporation. More concentrated solution makes catalyst inks less spread out on a substrate surface, leading to larger droplet height and larger contact angle. Ambient relative humidity has a significant impact on catalyst deposition patterns. Under low relative humidity condition, catalyst particles are concentrated both near the central and the periphery of the droplet; while under high relative humidity, the central part is uniform, and the particles move towards the edge of the deposition, forming a stripe-like structure. This indicates that ink dilution and evaporation is key to the CL microstructure formation and must be properly controlled in order to obtain the quality and consistency of the CLs in fabrication
Electrocatalytic determination of sulfite using a modified carbon nanotubes paste electrode: application for determination of sulfite in real samples
A FTIR microspectroscopy study of the structural and biochemical perturbations induced by natively folded and aggregated transthyretin in HL-1 cardiomyocytes
Protein misfolding and aggregation are associated with a number of human degenerative diseases. In spite of the enormous research efforts to develop effective strategies aimed at interfering with the pathogenic cascades induced by misfolded/aggregated peptides/proteins, the necessary detailed understanding of the molecular bases of amyloid formation and toxicity is still lacking. To this aim, approaches able to provide a global insight in amyloid-mediated physiological alterations are of importance. In this study, we exploited Fourier transform infrared microspectroscopy, supported by multivariate analysis, to investigate in situ the spectral changes occurring in cultured intact HL-1 cardiomyocytes exposed to wild type (WT) or mutant (L55P) transthyretin (TTR) in native, or amyloid conformation. The presence of extracellular deposits of amyloid aggregates of WT or L55P TTR, respectively, is a key hallmark of two pathological conditions, known as senile systemic amyloidosis and familial amyloid polyneuropathy. We found that the major effects, associated with modifications in lipid properties and in the cell metabolic/phosphorylation status, were observed when natively folded WT or L55P TTR was administered to the cells. The effects induced by aggregates of TTR were milder and in some cases displayed a different timing compared to those elicited by the natively folded protein