239 research outputs found
Impacto do aumento da concentração de CO2 atmosférico sobre a microbiota do solo rizosférico de arroz.
A intensificação da atividade antrópica está causando significativo aumento da concentração de dióxido de carbono (CO2) na atmosfera, resultando em alterações no clima do planeta que devem ser acentuadas nas próximas décadas. Além das mudanças climáticas previstas, impactos também ocorrerão no ambiente biótico. O trabalho teve por objetivo avaliar os efeitos do aumento do CO2 atmosférico na microbiota do solo rizosférico de arroz (cultivar Agulha Precoce), em ensaio conduzido em estufas de topo aberto. Os tratamentos com injeção automatizada do gás apresentaram concentração média de 613 ppm de CO2. Como testemunha, foram utilizadas parcelas sem estufa e sem injeção do gás. Não houve efeito dos tratamentos no carbono da biomassa microbiana, na hidrólise de diacetato de fluoresceína, no desprendimento de CO2 e na condutividade elétrica do solo rizosférico e no número de bactérias diazotróficas endofíticas isoladas das raízes utilizando-se meio de cultura JNFb semi-específico para Herbaspirillum. Os tratamentos com estufa apresentaram aumento do pH do solo, sendo que o maior aumento foi obtido no tratamento com injeção de CO2
Development of a PCR assay for the detection of animal tissues in ruminant feeds.
The European Community ban on use of meat and bone meal in ruminant feed, as a consequence of the spread of bovine spongiform encephalopathy in Europe, has prompted a number of investigations about the possibility of detecting animal tissues in feedstuff. In this paper, a study on vertebrate primers, designed in the 16S rRNA gene of mitochondrial DNA, is described. These primers were able to amplify fragments that contained between 234 and 265 bp. The fragments were specific for bovine, porcine, goat, sheep, horse, rabbit, chicken, trout, and European pilchard and were confirmed by sequence analysis amplicons. The primers were used in a PCR assay applied to five samples of meat and blood meals of different species and subjected to severe rendering treatments (134.4 to 141.9 degrees C and 3.03 to 4.03 bar for 24 min). The presence of vertebrate tissues was detected in all samples. The assay proved to be rapid and sensitive (detection limit 0.0625%). It can be used as a routine method to detect animal-derived ingredients in animal feedstuff
Tuberculosis in roe deer from Spain and Italy
TUBERCULOSIS (TB) is a chronic infectious disease caused by bacteria
of the genus Mycobacterium (Grange and others 1990). The detection
of wildlife reservoirs of disease is important, particularly in areas where
there is a relatively low incidence of the disease in domestic animals.
Tuberculosis cases in roe deer (Capreolus capreolus) are reported only
sporadically, despite the wide distribution and the abundance of this cervid.
Roe deer with TB have been reported in Germany (Schmidt 1938),
Switzerland (Bouvier 1963), France (Zanella and others 2008) and the
UK (Gunning 1985, Delahay and others 2007). This short communication
is the first report of TB in roe deer in Spain and Italy, and discusses
the implications of these findings for wildlife and livestock disease control.
The prevalence of mycobacterial infections, such as TB and paratuberculosis,
seems to be increasing in Spain. Wildlife species may act as disease
reservoirs, so this short communication also elucidates the epidemiology
of mycobacterial infections in species such as roe deer
Golem95C: A library for one-loop integrals with complex masses
We present a program for the numerical evaluation of scalar integrals and
tensor form factors entering the calculation of one-loop amplitudes which
supports the use of complex masses in the loop integrals. The program is built
on an earlier version of the golem95 library, which performs the reduction to a
certain set of basis integrals using a formalism where inverse Gram
determinants can be avoided. It can be used to calculate one-loop amplitudes
with arbitrary masses in an algebraic approach as well as in the context of a
unitarity-inspired numerical reconstruction of the integrand.Comment: 22 pages, 3 figure
Higgs Interference Effects in \Pg \Pg \to \PZ\PZ and their Uncertainty
Interference between the Standard Model Higgs boson and continuum
contributions is considered in the heavy-mass scenario. Results are available
at leading order for the background. It is discussed how to combine the result
with the next-to-next-to-leading order Higgs production cross-section and a
proposal for estimating the associated theoretical uncertainty is presented.Comment: 25 pages, 10 figures; improved numerical accuracy, Numerics updated,
conclusions unchanged, references added. v
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