717 research outputs found
A Jeziorski-Monkhorst fully uncontracted Multi-Reference perturbative treatment I: principles, second-order versions and tests on ground state potential energy curves
The present paper introduces a new multi-reference perturbation approach
developed at second order, based on a Jeziorsky-Mokhorst expansion using
individual Slater determinants as perturbers. Thanks to this choice of
perturbers, an effective Hamiltonian may be built, allowing for the dressing of
the Hamiltonian matrix within the reference space, assumed here to be a CAS-CI.
Such a formulation accounts then for the coupling between the static and
dynamic correlation effects. With our new definition of zeroth-order energies,
these two approaches are strictly size-extensive provided that local orbitals
are used, as numerically illustrated here and formally demonstrated in the
appendix. Also, the present formalism allows for the factorization of all
double excitation operators, just as in internally contracted approaches,
strongly reducing the computational cost of these two approaches with respect
to other determinant-based perturbation theories. The accuracy of these methods
has been investigated on ground-state potential curves up to full dissociation
limits for a set of six molecules involving single, double and triple bond
breaking. The spectroscopic constants obtained with the present methods are
found to be in very good agreement with the full configuration interaction
(FCI) results. As the present formalism does not use any parameter or
numerically unstable operation, the curves obtained with the two methods are
smooth all along the dissociation path.Comment: 4 figures, 18 page
Toward the S3DVAR data assimilation software for the Caspian Sea
Data Assimilation (DA) is an uncertainty quantification technique used to incorporate observed data into a prediction model in order to improve numerical forecasted results. The forecasting model used for producing oceanographic prediction into the Caspian Sea is the Regional Ocean Modeling System (ROMS). Here we propose the computational issues we are facing in a DA software we are developing (we named S3DVAR) which implements a Scalable Three Dimensional Variational Data Assimilation model for assimilating sea surface temperature (SST) values collected into the Caspian Sea with observations provided by the Group of High resolution sea surface temperature (GHRSST). We present the algorithmic strategies we employ and the numerical issues on data collected in two of the months which present the most significant variability in water temperature: August and March
Glutathione increase by the n-butanoyl glutathione derivative (GSH-C4) inhibits viral replication and induces a predominant Th1 immune profile in old mice infected with influenza virus
During aging, glutathione (GSH) content declines and the immune system undergoes a
deficiency in the induction of Th1 response. Reduced secretion of Th1 cytokines, which is
associated with GSH depletion, could weaken the host defenses against viral infections.
We first evaluated the concentration of GSH and cysteine in organs of old mice; then, the
effect of the administration of the N-butanoyl GSH derivative (GSH-C4) on the response of
aged mice infected with influenza A PR8/H1N1 virus was studied through the determination
of GSH concentration in organs, lung viral titer, IgA and IgG1/IgG2a production and
Th1/Th2 cytokine profile.
Old mice had lower GSH than young mice in organs. Also the gene expression of
endoplasmic reticulum (ER) stress markers involved in GSH metabolism and folding of
proteins, i.e. Nrf2 and PDI, was reduced. Following infection, GSH content remained low
and neither infection nor GSH-C4 treatment affected Nrf2 expression. In contrast, PDI
expression was upregulated during infection and appeared counterbalanced by GSH-C4.
Moreover, the treatment with GSH-C4 increased GSH content in organs, reduced viral
replication and induced a predominant Th1 response.
In conclusion, GSH-C4 treatment could be used in the elderly to contrast influenza virus
infection by inducing immune response, in particular the Th1 profile
Design and evaluation of buccal adhesive hydrocortisone acetate (HCA) tablets.
Many studies have shown that topical buccal therapy with steroid anti-inflammatory drugs is useful in controlling ulcerative and inflammatory mucosal diseases. This local treatment is based on the concept that a high activity of steroids can be produced at the site of administration and, at the same time, the degree of systemic side effects can be minimized or avoided. In this study we developed a new formulation consisting of a mucoadhesive tablet formulation for buccal administration of hydrocortisone acetate (HCA). Three types of tablet were developed containing three mucoadhesive components: hydroxypropylmethyl cellulose (Methocel K4M), carboxyvinyl polymer (Carbopol 974P), and polycarbophyl (Noveon AA1); the first polymer is a cellulose derivative, the others are both polyacrylic acid derivatives. For each of those, three tablet batches were produced changing the quantity of the mucoadhesive component (10, 20, and 30%), resulting in 9 different formulations. The compatibility of HCA with all excipients using Differential Scanning Calorimetry (DSC) was assessed. Tablets were manufactured by wet granulation followed by compression. Technological controls on granulates (Hausner index, Carr index, granulometry and Karl-Fischer percentage humidity) and tablets (thickness, diameter, friability, hardness, uniformity of content, weigh uniformity and dissolution kinetic) were carried out. Mucoadhesion properties, ex vivo permeability through porcine buccal mucosa, in vivo behavior and compliance were evaluated. Technological controls have demonstrated that the increase in the (percentage) of mucoadhesive causes an increase in granulometry followed by a reduction in the granulate flowability, however all the tablets have given satisfactory technological results and conformed to the 3rd Ed. European Pharmacopoeia specifications. Mucoadhesion, ex vivo permeability and in vivo behavior results notably differed among tablets, depending on the quality and quantity of the mucoadhesive component. An overall comparison of results showed the tablets containing Carbopol 20% resulted to be the best formulation among those developed
DiagnĂłstico da fertilidade do solo e do estado nutricional de pimenteira-do-reino na TransamazĂ´nica, em agricultura familiar.
bitstream/item/48624/1/Boletim-PD-24-AMAZ-ORIENTAL.pd
Aprendizagem da Virtude em AristĂłteles
Resumo: O objetivo deste trabalho Ă© de destacar a posição aristotĂ©lica no contexto da Paideia grega. Para a Ética de AristĂłteles, virtude implica uma formação, ninguĂ©m se torna virtuoso por natureza, mas por costume. O conceito de virtude tende a ser esclarecido pelo entendimento de seu processo de aquisição. Tal aprendizagem se dá em dois nĂveis: em um se aprende a reconhecer a virtude em ato, pois, sua prática implica de certo modo conhecimento ou sabedoria; o outro remete Ă gĂŞnese dos hábitos na experiĂŞncia, sendo justamente pela experiĂŞncia de prazer e dor que se forma o gosto pelas ações virtuosas.Palavras-chave: virtude, caráter, PaidĂ©ia, AristĂłteles, prazer.Abstract: The objective of this work is to highlight the position of Aristotle in the context of Greek paideia. For Aristotle, virtue involves education, no one becomes virtuous by nature but by custom. The concept of virtue tends to be clarified by understanding the process of acquisition. This learning takes place at two levels: one leads to recognize the virtue in action, because this practice involves knowledge or wisdom, the other refers to what is earned by experience, and is just because there is a experience of pleasure and pain is possible to get the appreciation for virtuous deeds.Keywords: virtue, character, Paideia, Aristotle, pleasure
Desidratação osmótica na produção de frutas passa e sulfitação.
bitstream/item/75667/1/art-020.pdfPublicado também em: Toda Fruta, 05 jan. 2010; Portal Dia de Campo, 27 jan. 2010
Mycorrhizal induction of phenolic compounds and antioxidant properties of fungi and seedlings during the early steps of symbiosis.
Ectomycorrhizal (ECM) symbiosis plays a major role in nutrient cycling and the functioning of forest ecosystems. Trees with well developed ectomycorrhizas are more resistant to environmental stresses such as drought and to biotic stresses such as root pathogens. The establishment of ECM symbiosis is triggered by signals produced by both partners. These signals lead to morphological changes and a complex development of specific structures in both the plant root and the fungus. The development of the ECM fungi, Paxillus involutus and Pisolithus arhizus, in presence and absence of the symbiont – Pinus pinaster- was evaluated, as well as their antioxidant properties and phenolic compounds composition in response to the symbiotic association. ECM fungi grew less in the presence of Pinus pinaster, with Pisolithus arhizus being less affected in growth and thus being more adapted to this association. Protocatechuic acid was found only in Paxillus involutus, while Pinus pinaster roots, both in association and isolated, proved to have other phenolic acids, such as p-hydroxybenzoic and p-coumaric acids. The symbiosis between Paxillus involutus and Pinus pinaster had no major effects on the symbionts, while the association between Pisolithus arhizus and Pinus pinaster seems to generally decrease the antioxidant effects of both symbionts, despite the increase in p-coumaric and cinnamic acids in the ECM fungi
Influence of mycorrhizal symbiosis in antioxidant potential of fungi and seedlings.
Ectomycorrhizal (ECM) symbiosis plays a major role in nutrient cycling and the functioning of forest ecosystems. Trees with well developed ectomycorrhizas are more resistant to environmental stresses such as drought and to biotic stresses such as root pathogens [1]. The establishment of ECM symbiosis is triggered by signals produced by both partners. These signals lead to morphological changes and a complex development of specific structures in both the plant root and the fungus [2]
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