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111.
Isabel M. Araújo Mário J. J. Branco Vitor H. Fernandes Gracinda M. S. Gomes N. Ruškuc 《Semigroup Forum》2001,63(1):49-62
Finite generation and presentability of general unions of semigroups, as well as of bands of semigroups, bands of monoids,
semilattices of semigroups and strong semilattices of semigroups, are investigated. For instance, it is proved that a band
Y of monoids S
α
(α∈ Y ) is finitely generated/presented if and only if Y is finite and all S
α
are finitely generated/presented. By way of contrast, an example is exhibited of a finitely generated semigroup which is
not finitely presented, but which is a disjoint union of two finitely presented subsemigroups.
January 21, 2000 相似文献
112.
Vitor Ponci Rafael C. Silva Fernanda Paula R. Santana Simone S. Grecco Clia Regina M. Fortunato Maria A. Oliveira Wothan Tavares-de-Lima Clarice R. Olivo Iolanda de Ftima L. Calvo Tibrio Kaio S. Gomes Carla M. Prado Joo Henrique G. Lago 《Molecules (Basel, Switzerland)》2020,25(22)
In the present work, the anti-inflammatory and antiasthmatic potential of biseugenol, isolated as the main component from n-hexane extract from leaves of Nectandra leucantha and chemically prepared using oxidative coupling from eugenol, was evaluated in an experimental model of mixed-granulocytic asthma. Initially, in silico studies of biseugenol showed good predictions for drug-likeness, with adherence to Lipinski’s rules of five (RO5), good Absorption, Distribution, Metabolism and Excretion (ADME) properties and no alerts for Pan-Assay Interference Compounds (PAINS), indicating adequate adherence to perform in vivo assays. Biseugenol (20 mg·kg−1) was thus administered intraperitoneally (four days of treatment) and resulted in a significant reduction in both eosinophils and neutrophils of bronchoalveolar lavage fluid in ovalbumin-sensitized mice with no statistical difference from dexamethasone (5 mg·kg−1). As for lung function parameters, biseugenol (20 mg·kg−1) significantly reduced airway and tissue damping in comparison to ovalbumin group, with similar efficacy to positive control dexamethasone. Airway hyperresponsiveness to intravenous methacholine was reduced with biseugenol but was inferior to dexamethasone in higher doses. In conclusion, biseugenol displayed antiasthmatic effects, as observed through the reduction of inflammation and airway hyperresponsiveness, with similar effects to dexamethasone, on mixed-granulocytic ovalbumin-sensitized mice. 相似文献
113.
114.
Bartosz J. Pachno Maciej Strzemski Sawomir Dresler Lubomír Adamec Kamila Wojas-Krawczyk Ireneusz Sowa Anna Danielewicz Vitor F. O. Miranda 《Molecules (Basel, Switzerland)》2021,26(1)
The genus Aldrovanda is a Palaeogene element containing a single extant species, Aldrovanda vesiculosa L. This aquatic carnivorous herb has a very wide range of distribution, natively covering four continents; however, it is a critically endangered aquatic plant species worldwide. Previous studies revealed that A. vesiculosa had an extremely low genetic variation. The main aim of the present paper is to explore, using chemometric tools, the diversity of 16 A. vesiculosa populations from various sites from four continents (Eurasia, Africa, Australia). Using chemometric data as markers for genetic diversity, we show the relationships of 16 A. vesiculosa populations from various sites, including four continents. Phytochemical markers allowed the identification of five well-supported (bootstrap > 90%) groups among the 16 populations sampled. The principal component analysis data support the idea that the strongly related African (Botswana) and Australian (Kimberley, NT, NW Australia) populations are the most distant ones, separated from the European and Asian ones. However, considering the five Australian populations sampled, three are nested within the Eurasian group. The chemometric data are correlated positively with the geographical distances between the samples, which suggests a tendency toward isolation for the most distant populations. 相似文献
115.
Josephine Blersch Dr. Vitor Francisco Catarina Rebelo Dr. Adrian Jiménez-Balsa Helena Antunes Dr. Carlo Gonzato Dr. Sandra Pinto Dr. Susana Simões Prof. Dr. Klaus Liedl Prof. Dr. Karsten Haupt Prof. Dr. Lino Ferreira 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(5):2001-2007
RNA-based therapies offer a wide range of therapeutic interventions including the treatment of skin diseases; however, the strategies to efficiently deliver these biomolecules are still limited due to obstacles related to the cellular uptake and cytoplasmic delivery. Herein, we report the synthesis of a triggerable polymeric nanoparticle (NP) library composed of 160 formulations, presenting physico-chemical diversity and differential responsiveness to light. Six formulations were more efficient (up to 500 %) than commercially available lipofectamine in gene-knockdown activity. These formulations showed differential internalization by skin cells and the endosomal escape was rapid (minutes range). The NPs were effective in the release of siRNA and miRNA. Acute skin wounds treated with the top hit NP complexed with miRNA-150-5p healed faster than wounds treated with scrambled miRNA. Light-activatable NPs offer a new strategy to topically deliver non-coding RNAs. 相似文献
116.
H. B. Jeppesen J. Byskov-Nielsen P. Wright J. G. Correia L. M. Fraile H. O. U. Fynbo K. Johnston K. Riisager 《The European Physical Journal A - Hadrons and Nuclei》2007,32(1):31-34
A possible dependence of the alpha decay process on the solid-state environment of the decaying nucleus has been investigated
by measuring the alpha-decay half-life of 221Fr at room temperature in different materials ( Au, W, Si and polyethylene). The change in half-life between the insulator
Si and the metals Au/ W is found to be 0.30(17)% / 0.42(21)%, respectivly. Furthermore an improved value of 4.79(2)min was
found for the absolute half-life of 221Fr. 相似文献
117.
In this Letter we consider the radial infall along the symmetry axis of an ultra-relativistic point particle into a rotating Kerr black hole. We use the Sasaki-Nakamura formalism to compute the waveform, energy spectra and total energy radiated during this process. We discuss possible connections between these results and the black hole-black hole collision at the speed of light process. 相似文献
118.
Let R be a commutative ring and G a free R-module with finite rank e>0. For any R-submodule E⊂G one may consider the image of the symmetric algebra of E by the natural map to the symmetric algebra of G, and then the graded components En, n≥0, of the image, that we shall call the n-th Rees powers of E (with respect to the embedding E⊂G). In this work we prove some asymptotic properties of the R-modules En, n≥0, which extend well known similar ones for the case of ideals, among them Burch’s inequality for the analytic spread. 相似文献
119.
Vitor H. Fernandes 《Semigroup Forum》1998,56(3):418-433
NO of all normally ordered inverse semigroups. We show that the pseudovariety of inverse semigroups PCS generated by all semigroups of injective and order partial transformations on a finite chain consists of all aperiodic elements
of NO . Also, we prove that NO is the join pseudovariety of inverse semigroups. PCS V G , where G is the pseudovariety of all finite groups. 相似文献
120.
M.L.S.Simōes Gonçalves M.M.Correia Dos Santos 《Journal of Electroanalytical Chemistry》1985,187(2):333-348
The complexation of cadmium with naturally occurring amino acids was studied at the ionic strength of seawater (0.70 M in sodium perchlorate medium) and at 25±0.1°C by differential pulse polarography and potentiometry with a glass electrode.The Miniquad program was used to analyse and refine the results of the potentiometry.Although the stability of the complexes is very similar since the chelate groups of the ligands are the same, the rate of dissociation of the complexes can be different.The kinetic aspect has been studied by cyclic voltammetry which is under the influence of the type of adsorption. When this is strong the diffusion and adsorption peaks are well separated and, in principle the rate constant of dissociation of the complex can be determined. If there is weak adsorption the diffusion peak is distorted by adsorption and kinetic studies cannot be done. the adsorption of the ligands themselves has been studied by ac polarography at a 90° angle phase and it has been noticed that ligands with π bonds, sulphur groups or with long hydrocarbon chains are more adsorbed than those without. 相似文献