6,536 research outputs found
Foeniculum vulgare Essential Oils: Chemical Composition, Antioxidant and Antimicrobial Activities
The essential oils from Foeniculum vulgare commercial aerial parts and fruits were isolated by hydrodistillation, with different distillation times (30 min, I h, 2 h and 3 h), and analyzed by GC and GC-MS. The antioxidant ability was estimated using four distinct methods. Antibacterial activity was determined by the agar diffusion method. Remarkable differences, and worrying from the quality and safety point of view, were detected in the essential oils. trans-Anethole (31-36%), alpha-pinene (14-20%) and limonene (11-13%) were the main components of the essentials oil isolated from F. vulgare dried aerial parts, whereas methyl chavicol (= estragole) (79-88%) was dominant in the fruit oils. With the DPPH method the plant oils showed better antioxidant activity than the fruits oils. With the TBARS method and at higher concentrations, fennel essential oils showed a pro-oxidant activity. None of the oils showed a hydroxyl radical scavenging capacity >50%, but they showed an ability to inhibit 5-lipoxygenase. The essential oils showed a very low antimicrobial activity. In general, the essential oils isolated during 2 h were as effective, from the biological activity point of view, as those isolated during 3 h.info:eu-repo/semantics/publishedVersio
Static quantities of a neutral bilepton in the 331 model with right-handed neutrinos
A neutral vector boson can possess static electromagnetic properties provided
that the associated field is no self-conjugate. This possibility is explored in
the model with right-handed neutrinos, which
predicts a complex neutral gauge boson in a nontrivial representation of
the electroweak group. In this model the only nonvanishing form factors are the
CP-even ones, which arise from both the quark and gauge sectors, and contribute
to the magnetic dipole and the electric quadrupole moments of this neutral
particle.Comment: 10 pages, 6 figures, submitted to Phys. Rev.
Qualidade das silagens de leucena (Leucaena leucocephala) e gliricÃdia (GliricÃdia sepium) sob diferentes épocas de abertura dos silos.
Avaliou-se silagens de Leucena (Leucaena leucocephala) e GliricÃdia (GliricÃdia sepium), produzidas em tubos de PVC, com 7, 14, 28 e 56 dias de fermentação, determinando-se os valores de matéria seca (MS), proteÃna bruta (PB), fibra em de tergente neutro (FDN), fibra em detergente ácido (FDA), extrato etéreo (EE), carboidratos não estruturais (CNE), digestibilidade in vitro da matéria seca (DIVMS) e pH. Os teores médios de MS, PB, FDN, FDA, DIVMS, pH e CNE apresentaram diferenças significativas entre as espécies forrageiras, não diferindo em relação ao teor de EE. Houve diferenças significativas para todos os parâmetros avaliados, exceto a MS, quando avaliados em função do tempo de incubação. As silagens de leucena e gliricÃdia apresentaram teores médios de MS (28,24 e 28,20%, respectivamente) inferiores a faixa recomendada como requisitos para a confecção de uma boa silagem. As silagens em estudo apresentaram altos nÃveis de PB, no entanto apresentaram baixa digestibilidade. Os valores de pH para ambas silagens foram elevados em todos os tempos de incubação, o que pode prejudicar o processo fermentativo
A note on the rare decay of a Higgs boson into photons and a boson
We have calculated the width of the rare decay at
one-loop level in the standard model for Higgs boson masses in the range . For this range of Higgs boson masses
we find that boson is predominantly longitudinally polarized, and the
photons have the same helicity. A comparison of the decay width to those of and shows that,
for the Higgs boson mass of , the ratios of the decay
widths are .Comment: 4 pages, 5 figures, RevTe
The imprints of bars on the vertical stellar population gradients of galactic bulges
This is the second paper of a series aimed to study the stellar kinematics
and population properties of bulges in highly-inclined barred galaxies. In this
work, we carry out a detailed analysis of the stellar age, metallicity and
[Mg/Fe] of 28 highly-inclined () disc galaxies, from S0 to S(B)c,
observed with the SAURON integral-field spectrograph. The sample is divided
into two clean samples of barred and unbarred galaxies, on the basis of the
correlation between the stellar velocity and h profiles, as well as the
level of cylindrical rotation within the bulge region. We find that while the
mean stellar age, metallicity and [Mg/Fe] in the bulges of barred and unbarred
galaxies are not statistically distinct, the [Mg/Fe] gradients along the minor
axis (away from the disc) of barred galaxies are significantly different than
those without bars. For barred galaxies, stars that are vertically further away
from the midplane are in general more [Mg/Fe]--enhanced and thus the vertical
gradients in [Mg/Fe] for barred galaxies are mostly positive, while for
unbarred bulges the [Mg/Fe] profiles are typically negative or flat. This
result, together with the old populations observed in the barred sample,
indicates that bars are long-lasting structures, and therefore are not easily
destroyed. The marked [Mg/Fe] differences with the bulges of unbarred galaxies
indicate that different formation/evolution scenarios are required to explain
their build-up, and emphasizes the role of bars in redistributing stellar
material in the bulge dominated regions.Comment: 22 pages, 7 main body figures +8 appendix figures, 2 tables. Accepted
by MNRA
Produtividade e valor nutritivo das frações forrageiras da erva-sal (Atriplex nummularia) irrigada com quatro diferentes volumes de efluentes da criação de tilápia em água salobra.
Avaliou-se a produtividade e o valor nutritivo da erva sal cultivada sob irrigação de quatro volumes de efluentes oriundos de viveiros de criação de tilápia (Oreochromis sp.), cuja salinidade média durante o cultivo foi de 8,29 dS m-l. O delÃneamento experimental foi de blocos ao acaso com quatrO tratamentos e três repetições. Os tratamentos de 75, 150, 225 e 300 litros de efluente por planta foram aplicados semanalmente. Os diferentes volumes de água influenciaram a produtividade de matéria seca, mas não influenciaram a composição quÃmico-bromatológica e digestibilidade in vitro da matéria seca em qualquer dos componentes da planta. Os teores de minerais (MM) mostraram-se elevados nas folhas, requerendo assim, cuidados com dietas contendo alta proporção de folhas de erva sal, a ponto de não permitir que teores elevados de sais sejam comprometedores do consumo animal. O teor de proteÃna bruta e digestibilidade Ãn vÃtro da matéria seca médio dos tratamentos para as folhas foi de 15,1 e 67,9%, respectivamente. Ramos e Caules apresentaram elevados teores de FDN e FDA e baixos valores de DIVMS. Independente do nÃvel de água aplicado, a erva sal mostrou caracterÃsticas forrageiras desejável, que podem ainda ser melhoradas com práticas de manejo voltadas para tal fim
Cost efficiency and resistance to chemical attack of a fly ash geopolymeric mortar versus epoxy resin and acrylic paint coatings
This article presents results of an experimental investigation on the resistance to chemical attack (with sulphuric, hydrochloric and nitric acid) of several materials: OPC concrete, high-performance concrete, epoxy resin, acrylic painting and a fly ash-based geopolymeric mortar). Three types of acids with three high concentrations (10, 20 and 30%) were used to simulate long-term degradation. A cost analysis was also performed. The results show that the epoxy resin has the best resistance to chemical attack independently of the acid type and the acid concentration. However, the cost analysis shows that the epoxy resin-based solution is the least cost-efficient solution being 70% above the cost efficiency of the fly ash-based geopolymeric mortar
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