Development of a novel cell encapsulation system based on natural origin polymers for tissue engineering applications

Cells microencapsulated in biocompatible semi-permeable polymeric membranes are effective as cell delivery systems while protecting the host against immune responses. In this study, cell encapsulation membranes were prepared based on carrageenan and alginate, two natural cationic polymers. Different formulations/conditions were explored to optimize the microcapsules which were characterized with respect to their morphology, mechanical stability, and cytotoxicity. Spherical-shaped microcapsules were obtained from all the polymeric systems. The iota-carrageenan/sodium alginate microcapsules exhibited the best stability and permeability, and therefore, these were selected for the cell encapsulation. These capsules provided an environment that supported cell proliferation and have the potential for tissue engineering as well as other cell-based therapy applications.One of the authors (SML) acknowledges the support of the Programme Alssan-the European Union Programme of High Level Scholarships for Latin America (scholarship no. E04M041362CO). This work was partially supported by the European STREP HIPPOCRATES (NMP3-CT-2003-505758) and by the Fundacao para a Ciencia e Tecnologia (project PTDC/QUI/68804/2006) and carried out under the scope of European NoE EXPERTISSUES (NMP3-CT-2004-500283)

Comunicación poliédrica: biopsia transformativa de la Biblioteca de Seattle

Photography is undoubtedly a fundamental tool in the narrative strategy of architecture, both in its creation as its “reproduction”. So much so, that allows us to create new different realities from a same object and gives rise to multiple interpretations. To understand how the communicative strategy has a strong impact on the perception of the architectural object, we turned to such a blunt, pregnant and iconic project as the Seattle Library of OMA. This building has appeared in countless different media related with architecture from such opposite perspectives that, in some cases, the project is unrecognizable. In this regard, we consider this case to be a paradigm of the polyform architectural communication. We will make a trip visiting different interpretations of this project basically depending on the perspective of photography to verify our hypothesis, after contextualizing the development of the project. We will start with the first OMA’s publication that reflected the project, which was “Content” (Ed. Taschen, 2004). Afterwards we will analyze the initial conceptual proposal submitted to the competition (OMA with LMN Architecture, Bruce Mau and Hans Werlemann), which turns out to be very revealing at a communicative level. Then we will study the development displayed in the web page of the local partners of OMA in Seattle, LMN Architects. Finally, to perform a full revision of the multiple communicative aspects of the project, we will seek the local press, whose code is intended to be for the general public. All those different approaches will lead us to conclude that the communication in architecture has necessary a strong influence in the message, both in its aspect and content, being an undisputed tool of projection and transformation.La fotografía es, indudablemente, una herramienta fundamental en la estrategia narrativa de la arquitectura, tanto en su creación como en su “reproducción”. Tanto es así, que permite originar nuevas realidades a partir de un mismo objeto reflejado y dar lugar a interpretaciones múltiples. Para llegar a comprender cómo la estrategia comunicativa incide en la percepción del objeto arquitectónico, recurrimos a un proyecto contundente, pregnante y con una carga objetual muy trascendente, como es la Biblioteca de Seattle, de OMA. Este proyecto ha sido reflejado en incontables medios relacionados con la arquitectura, desde perspectivas tan opuestas que, en determinadas visiones, el proyecto deja de ser reconocible. En este sentido, lo consideramos un paradigma de la comunicación arquitectónica poliédrica. Haremos un repaso por las interpretaciones más destacadas del proyecto en función de su diversidad, basándonos principalmente en la perspectiva fotográfica, de cara a verificar nuestra hipótesis. Comenzaremos por la primera publicación que reflejó este proyecto, que fue “Content” (Ed. Taschen, 2004). Después analizaremos la propuesta conceptual inicial que presentó OMA al concurso (junto a LMN Architecture, Bruce Mau y Hans Werlemann), que resulta especialmente reveladora a nivel de comunicación. Posteriormente estudiaremos la estrategia narrativa desarrollada por los socios locales de OMA en Seattle (el estudio LMN Architects) a través de su página web. Por último, para realizar un barrido completo por las múltiples facetas comunicativas del proyecto, acudimos a la reinterpretación que del mismo se hace en la prensa local, cuyo código va específicamente dirigido al público general. Todas estas aproximaciones tan diversas nos lleva a concluir que la comunicación en la arquitectura incide fuertemente en el mensaje, tanto en su forma como en su contenido, siendo una herramienta indiscutible de proyección y transformación

Dynamics of spherically symmetric spacetimes: hydrodynamics and radiation

Using the 3+1 formalism of general relativity we obtain the equations governing the dynamics of spherically symmetric spacetimes with arbitrary sources. We then specialize for the case of perfect fluids accompanied by a flow of interacting massless or massive particles (e.g. neutrinos) which are described in terms of relativistic transport theory. We focus in three types of coordinates: 1) isotropic gauge and maximal slicing, 2) radial gauge and polar slicing, and 3) isotropic gauge and polar slicing.Comment: submitted to Phys. Rev. D, 46 pages, RevTex file, no figure

Paleobiology of titanosaurs: reproduction, development, histology, pneumaticity, locomotion and neuroanatomy from the South American fossil record

Fil: García, Rodolfo A.. Instituto de Investigación en Paleobiología y Geología. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Salgado, Leonardo. Instituto de Investigación en Paleobiología y Geología. General Roca. Río Negro; ArgentinaFil: Fernández, Mariela. Inibioma-Centro Regional Universitario Bariloche. Bariloche. Río Negro; ArgentinaFil: Cerda, Ignacio A.. Instituto de Investigación en Paleobiología y Geología. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Carabajal, Ariana Paulina. Museo Carmen Funes. Plaza Huincul. Neuquén; ArgentinaFil: Otero, Alejandro. Museo de La Plata. Universidad Nacional de La Plata; ArgentinaFil: Coria, Rodolfo A.. Instituto de Paleobiología y Geología. Universidad Nacional de Río Negro. Neuquén; ArgentinaFil: Fiorelli, Lucas E.. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica. Anillaco. La Rioja; Argentin

Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm{NN}}} = 2.76 TeV

The inclusive transverse momentum ($p_{\rm T}$) distributions of primary charged particles are measured in the pseudo-rapidity range $|\eta|<0.8$ as a function of event centrality in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}=2.76$ TeV with ALICE at the LHC. The data are presented in the $p_{\rm T}$ range $0.15<p_{\rm T}<50$ GeV/$c$ for nine centrality intervals from 70-80% to 0-5%. The Pb-Pb spectra are presented in terms of the nuclear modification factor $R_{\rm{AA}}$ using a pp reference spectrum measured at the same collision energy. We observe that the suppression of high-$p_{\rm T}$ particles strongly depends on event centrality. In central collisions (0-5%) the yield is most suppressed with $R_{\rm{AA}}\approx0.13$ at $p_{\rm T}=6$-7 GeV/$c$. Above $p_{\rm T}=7$ GeV/$c$, there is a significant rise in the nuclear modification factor, which reaches $R_{\rm{AA}} \approx0.4$ for $p_{\rm T}>30$ GeV/$c$. In peripheral collisions (70-80%), the suppression is weaker with $R_{\rm{AA}} \approx 0.7$ almost independently of $p_{\rm T}$. The measured nuclear modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/284

Measurement of charm production at central rapidity in proton-proton collisions at s=2.76\sqrt{s} = 2.76 TeV

The $p_{\rm T}$-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D$^0$, D$^+$, and D$^{*+}$ in the rapidity range $|y|<0.5$, and for transverse momentum $1< p_{\rm T} <12$ GeV/$c$, were measured in proton-proton collisions at $\sqrt{s} = 2.76$ TeV with the ALICE detector at the Large Hadron Collider. The analysis exploited the hadronic decays D$^0 \rightarrow$K$\pi$, D$^+ \rightarrow$K$\pi\pi$, D$^{*+} \rightarrow$D$^0\pi$, and their charge conjugates, and was performed on a $L_{\rm int} = 1.1$ nb$^{-1}$ event sample collected in 2011 with a minimum-bias trigger. The total charm production cross section at $\sqrt{s} = 2.76$ TeV and at 7 TeV was evaluated by extrapolating to the full phase space the $p_{\rm T}$-differential production cross sections at $\sqrt{s} = 2.76$ TeV and our previous measurements at $\sqrt{s} = 7$ TeV. The results were compared to existing measurements and to perturbative-QCD calculations. The fraction of cdbar D mesons produced in a vector state was also determined.Comment: 20 pages, 5 captioned figures, 4 tables, authors from page 15, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/307

Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}=2.76 TeV

The elliptic, $v_2$, triangular, $v_3$, and quadrangular, $v_4$, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions and (anti-)protons in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV with the ALICE detector at the Large Hadron Collider. Results obtained with the event plane and four-particle cumulant methods are reported for the pseudo-rapidity range $|\eta|<0.8$ at different collision centralities and as a function of transverse momentum, $p_{\rm T}$, out to $p_{\rm T}=20$ GeV/$c$. The observed non-zero elliptic and triangular flow depends only weakly on transverse momentum for $p_{\rm T}>8$ GeV/$c$. The small $p_{\rm T}$ dependence of the difference between elliptic flow results obtained from the event plane and four-particle cumulant methods suggests a common origin of flow fluctuations up to $p_{\rm T}=8$ GeV/$c$. The magnitude of the (anti-)proton elliptic and triangular flow is larger than that of pions out to at least $p_{\rm T}=8$ GeV/$c$ indicating that the particle type dependence persists out to high $p_{\rm T}$.Comment: 16 pages, 5 captioned figures, authors from page 11, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186

Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

The yield of charged particles associated with high-$p_{\rm T}$ trigger particles ($8 < p_{\rm T} < 15$ GeV/$c$) is measured with the ALICE detector in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jet-like correlation peaks in azimuthal di-hadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta $p_{\rm T}> 3$ GeV/$c$ on the away-side drops to about 60% of that observed in pp collisions, while on the near-side a moderate enhancement of 20-30% is found.Comment: 15 pages, 2 captioned figures, 1 table, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/350