1,983 research outputs found
Digital implementation of the cellular sensor-computers
Two different kinds of cellular sensor-processor architectures are used nowadays in various
applications. The first is the traditional sensor-processor architecture, where the sensor and the
processor arrays are mapped into each other. The second is the foveal architecture, in which a
small active fovea is navigating in a large sensor array. This second architecture is introduced
and compared here. Both of these architectures can be implemented with analog and digital
processor arrays. The efficiency of the different implementation types, depending on the used
CMOS technology, is analyzed. It turned out, that the finer the technology is, the better to use
digital implementation rather than analog
The Paleogene successions in the upper Ghomaride unit in Talembote (Internal Rif, Morocco)
43ª Sesión Científica. Móstoles, Noviembre de 2007The lower Paleogene stratigraphic successions of the Talembote upper Ghomaride Unit represent an interval
of age going from the (middle?) Ilerdian to the early Bartonian, showing a transgressive sequence interrupted
by intermittent sedimentary gaps, which are indicated by surfaces of discontinuity. These sediments
correspond essentially to carbonatic facies with benthic foraminifers deposited in a shallow platform that
was maintained probably until the late Lutetian. The abrupt rupture of this platform allowed, during the
early Bartonian, sedimentation of pelagic to hemipelagic facies in a bathyal sedimentary environment.
Later, the sudden interruption of the sedimentation in the early Bartonian, indicated by a paleosoil, may
be better explained by tectonic reason than eustatism taking into account many actual geodynamic
reconstructions.Esta nota se ha hecho en el marco
de la beca concedida a uno de los autores
(R.H) por la Agencia Española de
Cooperación Internacional (AECI) y
del proyecto CGL 2005-00404/BTE.Peer reviewe
Scissors modes in triaxial metal clusters
We study the scissors mode (orbital M1 excitations) in small Na clusters,
triaxial metal clusters and and the
close-to-spherical , all described in DFT with detailed ionic
background. The scissors modes built on spin-saturated ground and
spin-polarized isomeric states are analyzed in virtue of both macroscopic
collective and microscopic shell-model treatments. It is shown that the mutual
destruction of Coulomb and the exchange-correlation parts of the residual
interaction makes the collective shift small and the net effect can depend on
details of the actual excited state. The crosstalk with dipole and spin-dipole
modes is studied in detail. In particular, a strong crosstalk with spin-dipole
negative-parity mode is found in the case of spin-polarized states. Triaxiality
and ionic structure considerably complicate the scissors response, mainly at
expense of stronger fragmentation of the strength. Nevertheless, even in these
complicated cases the scissors mode is mainly determined by the global
deformation. The detailed ionic structure destroys the spherical symmetry and
can cause finite M1 response (transverse optical mode) even in clusters with
zero global deformation. But its strength turns out to be much smaller than for
the genuine scissors modes in deformed systems.Comment: 17 pages, 5 figure
T Lymphocytes Influence the Mineralization Process of Bone
Bone is a unique organ able to regenerate itself after injuries. This
regeneration requires the local interplay between different biological systems
such as inflammation and matrix formation. Structural reconstitution is
initiated by an inflammatory response orchestrated by the host immune system.
However, the individual role of T cells and B cells in regeneration and their
relationship to bone tissue reconstitution remain unknown. Comparing bone and
fracture healing in animals with and without mature T and B cells revealed the
essential role of these immune cells in determining the tissue mineralization
and thus the bone quality. Bone without mature T and B cells is stiffer when
compared to wild-type bone thus lacking the elasticity that helps to absorb
forces, thus preventing fractures. In-depth analysis showed dysregulations in
collagen deposition and osteoblast distribution upon lack of mature T and B
cells. These changes in matrix deposition have been correlated with T cells
rather than B cells within this study. This work presents, for the first time,
a direct link between immune cells and matrix formation during bone healing
after fracture. It illustrates specifically the role of T cells in the
collagen organization process and the lack thereof in the absence of T cells
Natural Occurrence of Ochratoxin A in Musts, Wines and Grape Vine Fruits from Grapes Harvested in Argentina
In this study, ochratoxin A (OTA) occurrence in Argentinean musts, wines and dried vine fruits was evaluated, alongside with the performance of OchraStarTM columns for OTA extraction. In all the three matrices analyzed, the OchraStarTM columns showed good performance. The analysis of natural occurrence of OTA in the red must and the red wine samples showed low incidence with low levels of mean OTA contamination (0.12 ng/mL and 0.37 ng/mL, respectively), while 60% of the dried vine fruit samples were contaminated with OTA, in levels ranging from 0.26 to 20.28 ng/g
Phage-Encoded Endolysins
Due to the global emergence of antibiotic resistance, there has been an increase in research surrounding endolysins as an alternative therapeutic. Endolysins are phage-encoded enzymes, utilized by mature phage virions to hydrolyze the cell wall from within. There is significant evidence that proves the ability of endolysins to degrade the peptidoglycan externally without the assistance of phage. Thus, their incorporation in therapeutic strategies has opened new options for therapeutic application against bacterial infections in the human and veterinary sectors, as well as within the agricultural and biotechnology sectors. While endolysins show promising results within the laboratory, it is important to document their resistance, safety, and immunogenicity for in-vivo application. This review aims to provide new insights into the synergy between endolysins and antibiotics, as well as the formulation of endolysins. Thus, it provides crucial information for clinical trials involving endolysins
Antifungal activity of a novel chromene dimer
The activity on Aspergillus spp. growth and on ochratoxin A production of two novel chromene dimers (3) was evaluated. The results of the bioassays indicate that the chromene dimer 3a inhibited mycelia growth by approximately 50% (EC50) at 140.1 μmol L−1 for A. niger, 384.2 μmol L−1 for A. carbonarius, 69.1 μmol L−1 for A. alliaceus and 559.1 μmol L−1 for A. ochraceus. When applied at concentrations of 2 mmol L−1, 3a totally inhibited the growth of all Aspergillus spp. tested. Furthermore, ochratoxin A production by A. alliaceus was reduced by about 94% with a 200 μmol L−1 solution of this compound. A moderate inhibitory effect was observed for the analogous structure 3b on ochratoxin A production but not in mycelia growth. No inhibition was registered for compounds 2a and 2b, used as synthetic precursors of the dimeric species 3.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/
11228/2002
Shape Selectivity by Guest- Driven Restructuring of a Porous Material
A flexible metal-organic framework selectively sorbs para- (pX) over meta-xylene (mX) by synergic restructuring around pX coupled with generation of unused void space upon mX loading. The nature of the structural change suggests more generally that flexible structures which are initially mismatched in terms of fit and capacity to the preferred guest are strong candidates for effective molecular separations
Silicon-hydroxyapatite bioactive coatings (Si-HA) from diatomaceous earth and silica. Study of adhesion and proliferation of osteoblast-like cells
The aim of this study consisted on investigating
the influence of silicon substituted hydroxyapatite (Si–HA)
coatings over the human osteoblast-like cell line (SaOS-2)
behaviour. Diatomaceous earth and silica, together with
commercial hydroxyapatite were respectively the silicon
and HA sources used to produce the Si–HA coatings. HA
coatings with 0 wt% of silicon were used as control of the
experiment. Pulsed laser deposition (PLD) was the selected
technique to deposit the coatings. The Si–HA thin films
were characterized by Fourier Transformed Infrared
Spectroscopy (FTIR) demonstrating the efficient transfer of
Si to the HA structure. The in vitro cell culture was
established to assess the cell attachment, proliferation and
osteoblastic activity respectively by, Scanning Electron
Microscopy (SEM), DNA and alkaline phosphatase (ALP)
quantification. The SEM analysis demonstrated a similar
adhesion behaviour of the cells on the tested materials and
the maintenance of the typical osteoblastic morphology
along the time of culture. The Si–HA coatings did not
evidence any type of cytotoxic behaviour when compared
with HA coatings. Moreover, both the proliferation rate
and osteoblastic activity results showed a slightly better
performance on the Si–HA coatings from diatoms than on
the Si–HA from silica.This work was supported by the UE-Interreg IIIA (SP1.P151/03) Proteus project and Xunta de Galicia ( Projects: 2006/12 and PGIDITO5PXIC30301PN)
Unraveling the chemical composition, antioxidant, α-amylase and α-glucosidase inhibition of Moroccan propolis
In the present study, seven propolis samples collected from different areas of Morocco were evaluated for various potential attributes. Physicochemical parameters (moisture, pH, soluble substance, insoluble substance, ash content, conductivity, organic matter, resin, balsams, total carbohydrates, total proteins and mineral content), structural characterization by FTIR, phenolic and flavonoid composition and some biological activities (antioxidant, and -glucosidase and -amylase inhibitory activities) were determined. The analyzed physicochemical parameters showed the following values: moisture (3.35.2%), pH (4.15.5), soluble substance (66.175.4%), insoluble substance (23.833.7%), ashes (1.62.3%), conductivity (1.52.5 mS/cm), organic matter (97.7098.4%), wax (19.751.5%), resin (46.875.2%), balsam (1.53.1%), total carbohydrates (1.52.0 mg Glceq/g), and total proteins (1.76.2 g/100 g). Calcium, sodium, potassium, and magnesium were the most predominant minerals present in propolis samples. The phytochemical composition indicated the presence of phenolic acids, flavonoids and stilbens compounds described as having a high antioxidant capacity and potential -amylase (IC50 = 195.09963.79 g/mL) and -glucosidase (IC50 = 90.99876.24 g/mL) inhibitory activities. Moreover, FTIR spectra showed that the samples are structurally different between them, validating the results of the physicochemical analysis. The outcome of this study provides relevant information about Moroccan propolis composition and quality standards.This work was supported by a grant from University Sidi Mohamed Ben Abdallah for. Laboratory of Natural Substances, Pharmacology, Environment, Modeling, Health and Quality of Life (SNAMOPEQ). This research was funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorteoperation (NORTE-01-0145-FEDER 000004) funded by the European Regional Development Fund (FEDER) under the scope of Norte2020-Programa Operacional Regional do Norte. Zlatina Genisheva is supported by the project OH2O (POCI-01-0145- FEDER-029145) funded by FCT and FEDER under the scope of ProgramaOperacional de Competividade e Internacionalizaçao (POCI)- COMPETE 2020 and PORTUGAL 2020.info:eu-repo/semantics/publishedVersio
- …