5,552 research outputs found
Cortical Activation Patterns of Cue-Paced Foot Movement in Subacute Stroke Patients
[EN] Limb movement is associated with well defined cortical activation patterns. Structural and functional changes in the brain affect the characteristics of these patterns (strength and topography). Novel strategies for poststroke motor rehabilitation could monitor cortical activity as an additional index of engagement and/or recovery. In this work we analyze differences in cortical activation related to movements of the affected vs. unaffected foot (dorsiflexion). Our results show stronger cortical activation during movements of the affected foot, and stronger responses at the vertex. Online assessment of cortical activation and the experiment described in this work could be added to traditional motor rehabilitation.This work was supported by the FP7 EU Research Project BETTER (247935). The authors are thankful to Silvia Mena del Horno and Javier Bonilla for assistance during the experiments.Belda Lois, JM. (2013). Cortical Activation Patterns of Cue-Paced Foot Movement in Subacute Stroke Patients. Biomedical Engineering / Biomedizinische Technik. 58(1):1-2. https://doi.org/10.1515/bmt-2013-4446S1258
Inflation with a constant ratio of scalar and tensor perturbation amplitudes
The single scalar field inflationary models that lead to scalar and tensor
perturbation spectra with amplitudes varying in direct proportion to one
another are reconstructed by solving the Stewart-Lyth inverse problem to
next-to-leading order in the slow-roll approximation.
The potentials asymptote at high energies to an exponential form,
corresponding to power law inflation, but diverge from this model at low
energies, indicating that power law inflation is a repellor in this case. This
feature implies that a fine-tuning of initial conditions is required if such
models are to reproduce the observations. The required initial conditions might
be set through the eternal inflation mechanism.
If this is the case, it will imply that the spectral indices must be nearly
constant, making the underlying model observationally indistinguishable from
power law inflation.Comment: 20 pages, 7 figures. Major changes to the Introduction following
referee's comments. One figure added. Some other minor changes. No conclusion
was modifie
The transcription factor Spores Absent A is a PKA dependent inducer of Dictyostelium sporulation
Abstract Sporulation in Dictyostelium fruiting bodies evolved from amoebozoan encystation with both being induced by cAMP acting on PKA, but with downstream components still being unknown. Using tagged mutagenesis to find missing pathway components, we identified a sporeless mutant defective in a nuclear protein, SpaA. Expression of prespore genes was strongly reduced in spaA- cells, while expression of many spore stage genes was absent. Chromatin immunoprecipitation (ChIP) of a SpaA-YFP gene fusion showed that (pre)spore gene promoters bind directly to SpaA, identifying SpaA as a transcriptional regulator. SpaA dependent spore gene expression required PKA in vivo and was stimulated in vitro by the membrane-permeant PKA agonist 8Br-cAMP. The PKA agonist also promoted SpaA binding to (pre)spore promoters, placing SpaA downstream of PKA. Sequencing of SpaA-YFP ChIPed DNA fragments revealed that SpaA binds at least 117 (pre)spore promoters, including those of other transcription factors that activate some spore genes. These factors are not in turn required for spaA expression, identifying SpaA as the major trancriptional inducer of sporulation
Mitochondrial Metabolism, Dysfunctions in Senescence Cell and the Possible Interventions through Herbal Medicines
The mitochondria are the cell`s powerhouse. They are considered ubiquitous organelles of all eukaryotic cells, being responsible for the cell’s life and death cycle. Through stimuli in the environment in which they live, mitochondria can modulate their own biogenesis as well as signal retrograde to the nucleus to modify the structure of their proteins. Since the mitochondrial genome contains only 37 genes, much of the encoding of its proteins depends on the nuclear genome. Thus, the communication between mitochondria and the nucleus seems to be a target of science in understanding the pathologies associated with this organelle. Some medicinal herbs have been shown to influence mitochondrial biogenesis, such as Gynostemma pentaphyllun (GP) and berberine, which increase the phosphorylation of proteins AMPactivated protein kinase (AMPK). Just as GP and berberine phosphorylate AMPK in signaling for mitochondrial biogenesis, the sesquiterpene beta-caryophyllene (BCP) demonstrated positive results in reorganizing mitochondrial transcription factors, being an agonist of the peroxisome proliferatoractivated alpha receptor (PPAR-?). Another plant derivative, the non-psychoactive cannabinoid known as cannabidiol (CBD), has been showing control in the metabolism of calcium in the mitochondrial matrix. In this review, we seek to get a closer look at the biochemical mechanisms of action of some of these plants, as well as their synergies in the results of different treatments. In the view of oriental medicines, the use of associated medicinal herbs has always been part of their treatment protocols. However, the effectiveness of these treatments in relation to plant synergy can be observed in future clinical trials for better understanding
Red Iberoamericana de Toxicología y Seguiridad Química
La Red Iberoamericana de Toxicología y Seguridad Química RITSQ, se inicia en marzo de 2008 y desde entonces ha tenido 67.479 visitas a la página web de la misma, se han registrado 1.133 personas de 41 países y desde entonces hemos realizado y presentado 57 carteles en Reuniones, Conferencias y Reuniones donde se mantienen de forma constante los Objetivos de la RITSQ: 1. Coordinar la participación de los diferentes grupos existentes en universidades y organismos de investigación de Iberoamérica, implicados en estudios relacionados con la Toxicología, 2. Fortalecer la colaboración y el intercambio académico entre los programas de Doctorado y Maestría de diferentes países iberoamericanos que tengan como objeto el estudio y la investigación en Toxicología o áreas relacionadas, 3. Favorecer la realización de proyectos de investigación conjuntos entre docentes e investigadores de Iberoamérica, pasantías estudiantiles y eventos académicos; 4. Profundizar en el estudio de métodos de ensayo de corta y larga duración utilizados en la evaluación de la carcinogenicidad, la mutagenicidad y la toxicidad para la reproducción de sustancias y mezclas de productos químicos, 5. Desarrollar y estandarizar métodos analíticos para la identificación y determinación de biomarcadores de exposición, efecto y .susceptibilidad para sustancias y productos químicos en el hombre y el medio ambiente; 6. Aplicar métodos de evaluación del riesgo para la salud humana y el medio ambiente de sustancias y productos químicos, 7. Fomentar el intercambio científico de profesionales interesados alimentaria; y 8. Propiciar el uso de métodos alternativos a la experimentación animal (www.remanet.net).Peer reviewe
Shear induced instabilities in layered liquids
Motivated by the experimentally observed shear-induced destabilization and
reorientation of smectic A like systems, we consider an extended formulation of
smectic A hydrodynamics. We include both, the smectic layering (via the layer
displacement u and the layer normal p) and the director n of the underlying
nematic order in our macroscopic hydrodynamic description and allow both
directions to differ in non equilibrium situations. In an homeotropically
aligned sample the nematic director does couple to an applied simple shear,
whereas the smectic layering stays unchanged. This difference leads to a finite
(but usually small) angle between n and p, which we find to be equivalent to an
effective dilatation of the layers. This effective dilatation leads, above a
certain threshold, to an undulation instability of the layers. We generalize
our earlier approach [Rheol. Acta, vol.39(3), 15] and include the cross
couplings with the velocity field and the order parameters for orientational
and positional order and show how the order parameters interact with the
undulation instability. We explore the influence of various material parameters
on the instability. Comparing our results to recent experiments and molecular
dynamic simulations, we find a good qualitative agreement.Comment: 15 pages, 12 figures, accepted for publication in PR
Red Iberoamericana de Toxicología y Seguridad Química
La Red Iberoamericana de Toxicología y Seguridad Química RITSQ, se inicia en marzo de 2008 y desde entonces ha tenido 70.104 visitas a la página web de la misma, se han registrado 1.133 personas de 41 países y desde entonces hemos realizado y presentado 66 carteles en Reuniones, Conferencias y Reuniones donde se mantienen de forma constante los Objetivos de la RITSQ: 1. Coordinar la participación de los diferentes grupos existentes en universidades y organismos de investigación de Iberoamérica, implicados en estudios relacionados con la Toxicología, 2. Fortalecer la colaboración y el intercambio académico entre los programas de Doctorado y Maestría de diferentes países iberoamericanos que tengan como objeto el estudio y la investigación en Toxicología o áreas relacionadas, 3. Favorecer la realización de proyectos de investigación conjuntos entre docentes e investigadores de Iberoamérica, pasantías estudiantiles y eventos académicos; 4. Profundizar en el estudio de métodos de ensayo de corta y larga duración utilizados en la evaluación de la carcinogenicidad, la mutagenicidad y la toxicidad para la reproducción de sustancias y mezclas de productos químicos, 5. Desarrollar y estandarizar métodos analíticos para la identificación y determinación de biomarcadores de exposición, efecto y .susceptibilidad para sustancias y productos químicos en el hombre y el medio ambiente; 6. Aplicar métodos de evaluación del riesgo para la salud humana y el medio ambiente de sustancias y productos químicos, 7. Fomentar el intercambio científico de profesionales interesados alimentaria; y 8. Propiciar el uso de métodos alternativos a la experimentación animal (www.remanet.net).Peer reviewe
Red Iberoamericana de Toxicología y Seguridad Química
La Red Iberoamericana de Toxicología y Seguridad Química RITSQ, se inicia en marzo de 2008 y desde entonces ha tenido 69.930 visitas a la página web de la misma, se han registrado 1.133 personas de 41 países y desde entonces hemos realizado y presentado 66 carteles en Reuniones, Conferencias y Reuniones donde se mantienen de forma constante los Objetivos de la RITSQ: 1. Coordinar la participación de los diferentes grupos existentes en universidades y organismos de investigación de Iberoamérica, implicados en estudios relacionados con la Toxicología, 2. Fortalecer la colaboración y el intercambio académico entre los programas de Doctorado y Maestría de diferentes países iberoamericanos que tengan como objeto el estudio y la investigación en Toxicología o áreas relacionadas, 3. Favorecer la realización de proyectos de investigación conjuntos entre docentes e investigadores de Iberoamérica, pasantías estudiantiles y eventos académicos; 4. Profundizar en el estudio de métodos de ensayo de corta y larga duración utilizados en la evaluación de la carcinogenicidad, la mutagenicidad y la toxicidad para la reproducción de sustancias y mezclas de productos químicos, 5. Desarrollar y estandarizar métodos analíticos para la identificación y determinación de biomarcadores de exposición, efecto y .susceptibilidad para sustancias y productos químicos en el hombre y el medio ambiente; 6. Aplicar métodos de evaluación del riesgo para la salud humana y el medio ambiente de sustancias y productos químicos, 7. Fomentar el intercambio científico de profesionales interesados alimentaria; y 8. Propiciar el uso de métodos alternativos a la experimentación animal (www.remanet.net).Peer reviewe
Pollen segmentation and feature evaluation for automatic classification in bright-field microscopy
14 págs.; 10 figs.; 7 tabs.; 1 app.© 2014 Elsevier B.V. Besides the well-established healthy properties of pollen, palynology and apiculture are of extreme importance to avoid hard and fast unbalances in our ecosystems. To support such disciplines computer vision comes to alleviate tedious recognition tasks. In this paper we present an applied study of the state of the art in pattern recognition techniques to describe, analyze, and classify pollen grains in an extensive dataset specifically collected (15 types, 120 samples/type). We also propose a novel contour-inner segmentation of grains, improving 50% of accuracy. In addition to published morphological, statistical, and textural descriptors, we introduce a new descriptor to measure the grain's contour profile and a logGabor implementation not tested before for this purpose. We found a significant improvement for certain combinations of descriptors, providing an overall accuracy above 99%. Finally, some palynological features that are still difficult to be integrated in computer systems are discussed.This work has been supported by the European project APIFRESH
FP7-SME-2008-2 ‘‘Developing European standards for bee
pollen and royal jelly: quality, safety and authenticity’’ and we
would like to thank to Mr. Walter Haefeker, President of the European
Professional Beekeepers Association (EPBA). J. Victor Marcos
is a ‘‘Juan de la Cierva’’ research fellow funded by the Spanish Ministry
of Economy and Competitiveness. Rodrigo Nava thanks Consejo
Nacional de Ciencia y Tecnología (CONACYT) and PAPIIT Grant
IG100814.Peer Reviewe
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