20 research outputs found
Interaction between acrylic substrates and RAD16-I peptide in its self-assembling
[EN] Self-assembling peptides (SAP) are widely used as scaffolds themselves, and recently as fillers of microporous scaffolds, where the former provides a cell-friendly nanoenvironment and the latter improves its mechanical properties. The characterization of the interaction between these short peptides and the scaffold material is crucial to assess the potential of such a combined system. In this work, the interaction between poly(ethyl acrylate) (PEA) and 90/10 ethyl acrylate-acrylic acid copolymer P(EAcoAAc) with the SAP RAD16-I has been followed using a bidimensional simplified model. By means of the techniques of choice (congo red staining, atomic force microscopy (AFM), and contact angle measurements) the interaction and self-assembly of the peptide has proven to be very sensitive to the wettability and electro-negativity of the polymeric substrate.The authors acknowledge funding through the European Commission FP7 project RECATABI (NMP3-SL-2009-229239), and from the Spanish Ministerio de Ciencia e Innovacion through projects MAT2011-28791-C03-02 and -03. This work was also supported by the Spanish Ministerio de Educacion through M. Arnal-Pastor FPU 2009-1870 grant. The authors acknowledge the assistance and advice of Electron Microscopy Service of the UPV.Arnal Pastor, MP.; González-Mora, D.; García-Torres, F.; Monleón Pradas, M.; Vallés Lluch, A. (2016). Interaction between acrylic substrates and RAD16-I peptide in its self-assembling. 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Elsevier, pp. 367–43
Overview of recent TJ-II stellarator results
The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presented. ISSN:0029-5515 ISSN:1741-432
Latest physics results of TJ-II flexible heliac
This paper is devoted to the presentation of the most relevant recent Physics results obtained in the TJ-II flexible heliac. Firstly ECRH modulation and plasma breakdown studies are summarised; then the particle control techniques used to obtain reproducible discharges with density under control are presented. Transport studies show internal heat transport barriers that reduce heat conductivity to neoclassical values, and ELM-like transport events, similar to those observed in tokamaks and in other stellarators before and during H mode transition. Evidence of ExB sheared has been observed both in the proximity of rational surfaces. Finally, a high resolution Thomsom Scattering system has shown Te and ne profile structures
Perturbative transport experiments on TJ-II Flexible Heliac
Transport properties of TJ-II are explored performing perturbative experiments and taking advantage of TJ-II flexibility. Rotational transform can be varied in a wide range, which allows one to introduce low order rationals and to study their effect on transport. On the other hand, confinement properties can be studied at very different rotational transform values and for different values of magnetic shear: Experiments on influence of the magnetic shear on confinement are reported. In these cases a Ohmic current has been induced in TJ-II plasma to modify magnetic shear and to evaluate itsd effect on confinement, showing that negative shear improves the confinement. Heat transport is also reduced by locating a low order rational near the power deposition profile. Plasma potential profiles have been recently measured in some configurations up to the plasma core with the Heavy Ion Beam Probe (HIBP) diagnostic and the electric field values measured in low-density plasmas are consistent with neoclassical calculations near the plasma core. Plasma edge turbulent transport has been studied in configurations that are marginally stable due to decreased magnetic well. Results show a dynamical coupling between gradients and turbulent transport. Finally, cold pulse propagation has been studied showing ballistic non diffusive propagation
RESCUhE Project: Cultural Heritage vulnerability in a changing and directional climate
[EN] RESCUhE Project (Improving structural RESilience of Cultural HEritage to directional extreme hydro-meteorological events in the context of the Climate Change) is a coordinated IGME-UAM research project funded by Spanish Government (MCIN/AEI/10.13039/501100011033). The framework of this research is the predicted increase in climate change vulnerability of heritage sites and the current disconnection between both environmental research on material decay and the practical aspects of designing preventive conservation measurements.RESCUhE Project (Improving structural RESilience of Cultural HEritage to directional extreme hydro-meteorological events in the context of the Climate Change) is a coordinated IGME-UAM research project funded by Spanish Government (MCIN/AEI/10.13039/501100011033).Peer reviewe
Proteins specified by African swine fever virus - II. Analysis of proteins in infected cells and antigenic properties
Infection of MS cells with African swine fever virus (ASFV) produces inhibition of protein synthesis which is detectable from 4.5 hours after infection. At least 34 viral polypeptides have been indentified with molecular weights ranging between 9500 and 243,000 daltons. Three of these proteins show affinity for the cell nucleus and nine are in both the nuclear and cytoplasmic fractions. Ten early proteins were found, and most of the structural proteins were late proteins. Most of the proteins are synthesized within the first 8 hours after infection. At least nine proteins induced antibodies in the natural infection. Six of these proteins are structural proteins. The antigenic determinants of VP172, VP162, VP146, VP73, VP34, and IP23.5 are in the primary structure of the proteins. © 1980 Springer-Verlag
Proteins specified by African swine fever virus - I. Analysis of viral structural proteins and antigenic properties
At least 28 polypeptides have been identified in intracellular virus, with molecular weights ranging from 11,500 to 243,000 daltons. By treatment with Nonidet P-40 and 2-mercaptoethanol it is possible to obtain subviral particles that have lost some proteins and have a density in CsCl of 1.31 g/cm3 which is higher than that of the complete virus (1.23 g/cm3). After addition of NaCl the virus loses its major protein VP73 which indicates that it is localized in the viral envelope. Cores obtained after this treatment are made up of at least 14 proteins. Incorporation of3H-fucose and3H-glucosamine in intracellular virus occurs in three minor components. The protein VP42 is possibly the cell actin and appears to be strongly associated with the virus. It is not possible to eliminate it under conditions where the viral envelopes desappear morphologically. At least the proteins VP172, VP162, VP146 and VP73 act as antigens in the natural infection. © 1980 Springer-Verlag
Cardiac tissue engineering by electrical stimulation with subcutaneous and cardiac adipose-tissue derived progenitor cells (ATDPCs)
A major challenge of cardiac tissue engineering is directing cells to establish the physiological structure and function of the myocardium being replaced. In native heart, pacing cells generate electrical stimuli that spread throughout the heart
causing cell membrane depolarization and activation of contractile apparatus. We ought to examine whether electrical
stimulation of adipose tissue-derived progenitor cells (ATDPCs) exerts phenotypic and genetic changes that enhance their
cardiomyogenic potential.Peer ReviewedPostprint (published version
Cardiac tissue engineering by electrical stimulation with subcutaneous and cardiac adipose-tissue derived progenitor cells (ATDPCs)
A major challenge of cardiac tissue engineering is directing cells to establish the physiological structure and function of the myocardium being replaced. In native heart, pacing cells generate electrical stimuli that spread throughout the heart
causing cell membrane depolarization and activation of contractile apparatus. We ought to examine whether electrical
stimulation of adipose tissue-derived progenitor cells (ATDPCs) exerts phenotypic and genetic changes that enhance their
cardiomyogenic potential.Peer Reviewe