23 research outputs found
Effects of the Energy Error Distribution of Fluorescence Telescopes on the UHECR energy spectrum
The measurement of the ultra high energy cosmic ray (UHECR) spectrum is
strongly affected by uncertainties on the reconstructed energy. The
determination of the presence or absence of the GZK cutoff and its position in
the energy spectrum depends not only on high statistics but also on the shape
of the energy error distribution. Here we determine the energy error
distribution for fluorescence telescopes, based on a Monte Carlo simulation.
The HiRes and Auger fluorescence telescopes are simulated in detail. We analyze
the UHECR spectrum convolved with this energy error distribution. We compare
this spectrum with one convolved with a lognormal error distribution as well as
with a Gaussian error distribution. We show that the energy error distribution
for fluorescence detectors can not be represented by these known distributions.
We conclude that the convolved energy spectrum will be smeared but not enough
to affect the GZK cutoff detection. This conclusion stands for both HiRes and
Auger fluorescence telescopes. This result differs from the effect of the
energy error distribution obtained with ground detectors and reinforces the
importance of the fluorescence energy measurement. We also investigate the
effect of possible fluorescence yield measurement errors in the energy
spectrum.Comment: 24 pages, 11 figure
Probing the Conformational States of Thimet Oligopeptidase in Solution
Thimet oligopeptidase (TOP) is a metallopeptidase involved in the metabolism of oligopeptides inside and outside cells of various tissues. It has been proposed that substrate or inhibitor binding in the TOP active site induces a large hingeâbending movement leading to a closed structure, in which the bound ligand is enclosed. The main goal of the present work was to study this conformational change, and fluorescence techniques were used. Four active TOP mutants were created, each equipped with a singleâTrp residue (fluorescence donor) and a pânitroâphenylalanine (pNF) residue as fluorescence acceptor at opposite sides of the active site. pNF was biosynthetically incorporated with high efficiency using the amber codon suppression technology. Inhibitor binding induced shorter DonorâAcceptor (DâA) distances in all mutants, supporting the view that a hinge-like movement is operative in TOP. The activity of TOP is known to be dependent on the ionic strength of the assay buffer and DâA distances were measured at different ionic strengths. Interestingly, a correlation between the DâA distance and the catalytic activity of TOP was observed: the highest activities corresponded to the shortest DâA distances. In this study for the first time the hingeâbending motion of a metallopeptidase in solution could be studied, yielding insight about the position of the equilibrium between the open and closed conformation. This information will contribute to a more detailed understanding of the mode of action of these enzymes, including therapeutic targets like neurolysin and angiotensinâconverting enzyme 2 (ACE2)
Co-management of culturally important species:A tool to promote biodiversity conservation and human well-being
Co-management has been advocated as an effective tool to achieve natural resource conservation worldwide. Yet, the potential of co-management arrangements can fail to be realized when there is insufficient local engagement. In this perspective paper, we argue that co-management schemes focusing on culturally important species (CIS) can help overcome this issue by engaging local people's interest. To develop this theory, we explore published data on the outcomes of two management schemes, both encompassing multiple independent initiatives, to discuss CIS-management effects and benefits. We also show a compilation of CIS examples throughout the world and discuss the potential of CIS-management to reach a global audience. Based on these data, we argue that CIS-management can be an effective tool to reconcile the often intractable goals of biodiversity conservation and human welfare
Seletividade e dose de injĂșria econĂŽmica de nicosulfuron aplicado em diferentes estĂĄdios de desenvolvimento da cultura do milho
Desenvolvimento de plĂąntulas de pessegueiro 'Okinawa' inoculadas com micorrizas arbusculares isoladas de pomares de pessegueiros e de vinhedos
Caracterização morfolĂłgica e imuno-histoquĂmica de lesĂ”es em casos de aborto bovino bacteriano e viral no sul de Minas Gerais
Avaliação da biodiversidade de rizóbios simbiontes do feijoeiro (Phaseolus vulgaris L.) em Santa Catarina
Functionalization of smart recycled asphalt mixtures : a sustainability scientific and pedagogical approach
Physical and chemical characteristics of meat from lambs fed sorghum silage with cashew bagasse
Abstract This study was conducted to evaluate the effects of replacing forage sorghum for dehydrated cashew bagasse (DCB) in the proportions of 0; 8; 16 and 24%, based on the natural matter at the time of ensiling on the physicochemical parameters of meat from feedlot lambs. None of the physical parameters evaluated showed a significant difference between the substitution levels of sorghum forage for DCB. The final pH obtained in this study showed a value above the recommended for freshly slaughtered meat from animals 24 hours in refrigeration, being considered DFD meat (dark, firm and dry). Regarding the chemical parameters, it was observed that there were no significant differences between the levels of substitution of sorghum forage for DCB to variable moisture and ash was perceived negative linear effect for protein and quadratic effect on lipid levels meat. The replacement of forage sorghum up to 24% of dehydrated bagasse cashew the ensilage does not compromise the quality of the meat, however, the substitution of 8% is to be preferred because it provides meats with lower lipid content