Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 19 )

2019 ( 248 )

2018 ( 301 )

2017 ( 297 )

Custom range...

Search Results: 1 - 10 of 231089 matches for " Fermin Garcia C. Velasco "
All listed articles are free for downloading (OA Articles)
Page 1 /231089
Display every page Item
Knowing the Brazilian Atlantic Rainforest in childhood: a contribution of the theory of multiple intelligence for environmental education
Valerie Nicollier,Fermin Garcia C. Velasco
Investiga??es em Ensino de Ciências , 2009,
Abstract: This study is grounded in the cognitive sciences and represents a comprehensive inquiry into children's environmental knowledge. It started with an investigation of a specific situation: studying an urban population – stigmatized by a history of local environmental destruction, unconsciously wrought upon an area that is nowadays acknowledged as a natural biodiversity hotspot, the Brazilian Atlantic Rainforest. Based on the Multiple Intelligence Theory (MIT), that describes the presence of several intelligences in human beings, including a naturalist intelligence, this study aimed at improving the understanding of abilities related to environmental knowledge and the differentiation of such abilities from other ways of knowing usually valued in mainstream education. Forty-five (45) students of a primary school located in south Bahia, Brazil, their teachers, and their parents participated in this investigation between 2002 to 2004. Results suggest that the cognitive domains which are subjacent to environmental knowledge are place specific and need to be stimulated in primary schools by formulating more attractive, efficient, and innovative environmental educational methodologies.
Métodos físicos utilizados para oclus?o de varizes dos membros inferiores
Araújo, Marcelo;Velasco, Fermin de C. Garcia;
Jornal Vascular Brasileiro , 2006, DOI: 10.1590/S1677-54492006000200010
Abstract: the therapy of varicose veins of the lower limbs has classically been carried out with surgery and sclerotherapy, depending on vessel diameter. however, the association of techniques is frequently necessary to assure a good result. the use of physical procedures to promote occlusion of varicose veins was firstly attempted in the 1950s. there are different physical principles and effects based on different technological levels. electrocoagulation, laser, intense pulsed light, endovascular cryosclerosis, ultrasound and microwave are physical sources potentially useful for this condition. unfortunately, these technologies are not wide available outside research centers, with a few exceptions, and their role in clinical practice still needs to be defined. this paper aims to describe the physical procedures currently used or potentially useful for the therapy of varicose veins.
O encontro da política nacional da educa??o ambiental com a política nacional do idoso
Machado, Rosangela Fátima de Oliveira;Garcia Velasco, Fermin de La Caridad;Amim, Valéria;
Saúde e Sociedade , 2006, DOI: 10.1590/S0104-12902006000300013
Abstract: in this paper we discuss the convergence of two public policies: the national policy of environmental education and the national policy for old adults. we show a comparative view of the similarities and the contradictions in the application of those policies by the public administration. analysis of those policies indicates possibility of communitarian and institutional works where old aged ones could develop a relevant social role based on their past and present experiences, contributing to environmental sensitization of next generations. in this approach, we propose that old aged people - considering the summed experience - can act as advisor of an environmental education that offers to next generations a way to change personal concepts on environmental preservation, as a interdisciplinary inclusive work. to deal with those two public policies is a way to clarify and accelerate the implementation of key practices focused on improving personal life, environmental quality and interpersonal relations.
Multi-GPU based on multicriteria optimization for motion estimation system
Carlos Garcia, Guillermo Botella, Fermin Ayuso, Manuel Prieto and Francisco Tirado
EURASIP Journal on Advances in Signal Processing , 2013, DOI: 10.1186/1687-6180-2013-23
Abstract: Graphics processor units (GPUs) offer high performance and power efficiency for a large number of data-parallel applications. Previous research has shown that a GPU-based version of a neuromorphic motion estimation algorithm can achieve a x32 speedup using these devices. However, the memory consumption creates a bottleneck due to the expansive tree of signal processing operations performed. In the present contribution, an improvement in memory reduction was carried out, which limited accelerator viability usage. An evolutionary algorithm was used to find the best configuration. It supposes a trade-off solution between consumption resources, parallel efficiency, and accuracy. A multilevel parallel scheme was exploited: grain level by means of multi-GPU systems, and a finer level by data parallelism. In order to achieve a more relevant analysis, some optical flow benchmarks were used to validate this study. Satisfactory results opened the chance of building an intelligent motion estimation system that auto-adapted according to real-time, resource consumption, and accuracy requirements.
Selective Estrogen Receptor Modulators Regulate Dendritic Spine Plasticity in the Hippocampus of Male Rats
Ignacio González-Burgos,Martha C. Rivera-Cervantes,Dulce A. Velázquez-Zamora,Alfredo Feria-Velasco,Luis Miguel Garcia-Segura
Neural Plasticity , 2012, DOI: 10.1155/2012/309494
Abstract: Some selective estrogen receptor modulators, such as raloxifene and tamoxifen, are neuroprotective and reduce brain inflammation in several experimental models of neurodegeneration. In addition, raloxifene and tamoxifen counteract cognitive deficits caused by gonadal hormone deprivation in male rats. In this study, we have explored whether raloxifene and tamoxifen may regulate the number and geometry of dendritic spines in CA1 pyramidal neurons of the rat hippocampus. Young adult male rats were injected with raloxifene (1?mg/kg), tamoxifen (1?mg/kg), or vehicle and killed 24?h after the injection. Animals treated with raloxifene or tamoxifen showed an increased numerical density of dendritic spines in CA1 pyramidal neurons compared to animals treated with vehicle. Raloxifene and tamoxifen had also specific effects in the morphology of spines. These findings suggest that raloxifene and tamoxifen may influence the processing of information by hippocampal pyramidal neurons by affecting the number and shape of dendritic spines. 1. Introduction Selective estrogen receptor modulators (SERMs) either synthetic or natural, such as phytoestrogens, are candidates for the treatment or the prevention of cognitive and affective disorders in men and women [1–5]. Several studies have shown that some synthetic SERMs, such as tamoxifen, raloxifene, or bazedoxifene [6–29], some nonfeminizing estrogens [30–34], and some natural SERMs, such as genistein [35, 36], are neuroprotective in vitro and in vivo. The neuroprotective effects of SERMs are associated with a decrease in the activation of microglia and astroglia and a reduction in brain inflammation [37–43]. In addition, some SERMs have shown to induce neuritic outgrowth in vitro [44, 45], suggesting that these molecules may also affect synaptic connectivity in vivo. Indeed, ERs are involved in the regulation of dendritic spines in the hippocampus of female animals in vivo [46–51], where tamoxifen regulates synaptophysin expression [52]. SERMs are also able to regulate cholinergic, serotonergic, and dopaminergic neurotransmission in female animals [53–56]. However, the effects of SERMs on synaptic connectivity in males have not been adequately explored. Nevertheless, previous studies have shown that SERMs such as raloxifene and tamoxifen are able to counteract hippocampus-dependent cognitive deficits caused by androgen deprivation in male rats [57]. In addition, raloxifene reduces working memory deficits in male rats after traumatic brain injury [20]. To further characterize the mechanisms of action of SERMs in the male
Development of Novel Single-Stranded Nucleic Acid Aptamers against the Pro-Angiogenic and Metastatic Enzyme Heparanase (HPSE1)
Suzanne C. Simmons, Edward A. McKenzie, Lynda K. Harris, John D. Aplin, Paul E. Brenchley, Maria N. Velasco-Garcia, Sotiris Missailidis
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0037938
Abstract: Heparanase is an enzyme involved in extracellular matrix remodelling and heparan sulphate proteoglycan catabolism. It is secreted by metastatic tumour cells, allowing them to penetrate the endothelial cell layer and basement membrane to invade target organs. The release of growth factors at the site of cleaved heparan sulphate chains further enhance the potential of the tumour by encouraging the process of angiogenesis. This leads to increased survival and further proliferation of the tumour. Aptamers are single or double stranded oligonucleotides that recognise specific small molecules, peptides, proteins, or even cells or tissues and have shown great potential over the years as diagnostic and therapeutic agents in anticancer treatment. For the first time, single stranded DNA aptamers were successfully generated against the active heterodimer form of heparanase using a modified SELEX protocol, and eluted based on increasing affinity for the target. Sandwich ELISA assays showed recognition of heparanase by the aptamers at a site distinct from that of a polyclonal HPSE1 antibody. The binding affinities of aptamer to immobilised enzyme were high (7×107 to 8×107 M?1) as measured by fluorescence spectroscopy. Immunohistochemistry and immunofluorescence studies demonstrated that the aptamers were able to recognise heparanase with staining comparable or in some cases superior to that of the HPSE1 antibody control. Finally, matrigel assay demonstrated that aptamers were able to inhibit heparanase. This study provides clear proof of principle concept that nucleic acid aptamers can be generated against heparanase. These reagents may serve as useful tools to explore the functional role of the enzyme and in the future development of diagnostic assays or therapeutic reagents.
Estimation of the XUV radiation onto close planets and their evaporation
J. Sanz-Forcada,G. Micela,I. Ribas,A. M. T. Pollock,C. Eiroa,A. Velasco,E. Solano,D. Garcia-Alvarez
Physics , 2011, DOI: 10.1051/0004-6361/201116594
Abstract: Context: The current distribution of planet mass vs. incident stellar X-ray flux supports the idea that photoevaporation of the atmosphere may take place in close-in planets. Integrated effects have to be accounted for. A proper calculation of the mass loss rate due to photoevaporation requires to estimate the total irradiation from the whole XUV range. Aims: The purpose of this paper is to extend the analysis of the photoevaporation in planetary atmospheres from the accessible X-rays to the mostly unobserved EUV range by using the coronal models of stars to calculate the EUV contribution to the stellar spectra. The mass evolution of planets can be traced assuming that thermal losses dominate the mass loss of their atmospheres. Methods: We determine coronal models for 82 stars with exoplanets that have X-ray observations available. Then a synthetic spectrum is produced for the whole XUV range (~1-912 {\AA}). The determination of the EUV stellar flux, calibrated with real EUV data, allows us to calculate the accumulated effects of the XUV irradiation on the planet atmosphere with time, as well as the mass evolution for planets with known density. Results: We calibrate for the first time a relation of the EUV luminosity with stellar age valid for late-type stars. In a sample of 109 exoplanets, few planets with masses larger than ~1.5 Mj receive high XUV flux, suggesting that intense photoevaporation takes place in a short period of time, as previously found in X-rays. The scenario is also consistent with the observed distribution of planet masses with density. The accumulated effects of photoevaporation over time indicate that HD 209458b may have lost 0.2 Mj since an age of 20 Myr. Conclusions: Coronal radiation produces rapid photoevaporation of the atmospheres of planets close to young late-type stars. More complex models are needed to explain fully the observations.
Analysis by Light, Scanning, and Transmission Microscopy of the Intima Synovial of the Temporomandibular Joint of Human Fetuses during the Development
Carlos Sabu Alvez,Luis Otavio Carvalho de Moraes,Sergio R. Marques,Roberto C. Tedesco,Leandro J. C. Harb,Jose F. Rodríguez-Vázquez,Jose R. Mérida-Velasco,Luis Garcia Alonso
Anatomy Research International , 2014, DOI: 10.1155/2014/732720
Abstract: Objective. To characterize morphologically and ultrastructurally using light microscopy, the scanning electron microscopy and transmission electron microscopy the intima synovial of the temporomandibular joint (TMJ) of human fetuses between the 10th and the 38th week of development. Materials and Methods. The TMJ was dissected bilaterally in 37 human fetuses belonging to the Institute of Embryology of the University Complutense of Madrid and of the Federal University of S?o Paulo. Results. The outcome by light microscopy showed the morphology of the TMJ and that the formation of inferior joint cavity precedes the superior joint cavity and the presence of blood vessels in the synovial. Conclusion. By scanning and transmission electron microscopy we observed the presence of two well-defined cell types in the intima layer of synovial of the TMJ of human fetuses, macrophage-like type A cell and fibroblast-like type B cell, and the presence of the a third cell type, defined by the name of intermediate lining cell in the intima layer of the synovial. 1. Introduction The temporomandibular joint (TMJ) is a specialized synovial joint essential for the function of the mammalian jaw. The main components of the TMJ are the mandibular condyle, the mandibular fossa of the temporal bone, the articular disc with collagen fibers interposed with between them, and a synovial [1–5]. Morphologically, the synovial consists of two layers: one cellular intima layer and another for support, the vascular subintima layer, which combines with the articular capsule. The intima layer consists of cells within an amorphous and fiber-free matrix whose width varies approximately from 1 to 4 cells. The subintima layer consists of loose and vascularized connective tissue, with spread out fibroblasts, macrophages, mastocytes, adipose cells, and some elastic fibers that prevent the pleating of the [6–12]. The intima layer has cells with phagocytic ability called macrophage-like type A cell. This same layer also has cells called fibroblast-like B cells, which synthesize proteins, glycoproteins, and proteoglycans [9, 10, 13–16]. There is also a third type of cells not entirely studied yet called intermediate lining cell [6, 17–20]. Among these three cell types there are spaces filled with not very fibrous extracellular matrix and macrophage ground substance. The synovial fluid is formed in the synovial by blood vessel plasma in the subintima layer and travels to the articular space. As it crosses the intima layer, new elements secreted by fibroblast-like type B cells join in and the fluid
Broken Symmetries in Spacetime with Torsion and Galactic Magnetic Fields without Dynamo Amplification  [PDF]
L. C. Garcia de Andrade
International Journal of Astronomy and Astrophysics (IJAA) , 2012, DOI: 10.4236/ijaa.2012.23022
Abstract: Since Kostelecky et al [Phys Rev Lett 100, 111102 (2008)], have shown that there is an intimate connection between spacetime with torsion and the possibility of constraining it to Lorentz violation, a renewed interest in torsion theories of gravity has arised. In this paper, minimal coupling between photons on a torsioned background is shown to allow us to obtain the galactic magnetic field strength μG without dynamo amplification. This agrees with recent results by Jimenez and Maroto (2011) for spiral galaxies, with galactic magnetic field constraints from Dark matter without dy- namo amplification. The approach discussed here allow us to get rid of the unpleasant photon mass by simply consider- ing the Lagrangean cut off for second order torsion terms. Therefore though the gauge and Lorentz symmetries are bro- ken here one does not have to deal with photon masses.
The Efficiency of CP-Violating α2-Dynamos from Primordial Cosmic Axion Oscillation with Torsion  [PDF]
L. C. Garcia de Andrade
International Journal of Astronomy and Astrophysics (IJAA) , 2015, DOI: 10.4236/ijaa.2015.51008
Abstract: Recently torsion fields were introduced in CP-violating cosmic axion a2-dynamos [Garcia de Andrade, Mod Phys Lett A, (2011)] in order to obtain Lorentz violating bounds for torsion. Here instead, oscillating axion solutions of the dynamo equation with torsion modes [Garcia de Andrade, Phys Lett B (2012)] are obtained taking into account dissipative torsion fields. Magnetic helicity torsion oscillatory contribution is also obtained. Note that the torsion presence guarantees dynamo efficiency when axion dynamo length is much stronger than the torsion length. Primordial axion oscillations due to torsion yield a magnetic field of 109 G at Nucleosynthesis epoch. This is obtained due to a decay of BBN magnetic field of 1015 G induced by torsion. Since torsion is taken as 10–20 s–1, the dynamo efficiency is granted over torsion damping. Of course dynamo efficiency is better in the absence of torsion. In the particular case when the torsion is obtained from anomalies it is given by the gradient of axion scalar [Duncan et al., Nuclear Phys B 87, 215] that a simpler dynamo equation is obtained and dynamo mechanism seems to be efficient when the torsion helicity, is negative while magnetic field decays when the torsion is positive. In this case an extremely huge value for the magnetic field of 1015 Gauss is obtained. This is one order of magnitude greater than the primordial magnetic fields of the domain wall. Actually if one uses tDW ~ 10-4 s one obtains BDW ~ 1022 G which is a more stringent limit to the DW magnetic primordial field.
Page 1 /231089
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.