Consistent beta values from density-density and velocity-velocity comparisons

We apply a new algorithm, called the Unbiased Minimal Variance (hereafter UMV) estimator, to reconstruct the cosmic density and peculiar velocity fields in our local universe from the SEcat catalog of peculiar velocities comprising both early (ENEAR) and late type (SFI) galaxies. The reconstructed fields are compared with those predicted from the IRAS PSCz galaxy redshift survey to constrain the value of beta = Omega_m^{0.6}/b, where Omega_m and b are the mass density and the bias parameters. The comparison of the density and velocity fields is carried out within the same methodological framework, and leads, for the first time, to consistent values of beta, yielding beta = 0.57_{-0.13}^{+0.11} and beta = 0.51 +/- {0.06}, respectively. We find that the distribution of the density and velocity residuals, relative to their respective errors, is consistent with a Gaussian distribution with sigma approximately 1, indicating that the density field predicted from the PSCz is an acceptable fit to that deduced from the peculiar velocities of the SEcat galaxies.Comment: 15 pages, 12 figures, accepted for publication in MNRA

Large-Scale Power Spectrum and Structures From the ENEAR galaxy Peculiar Velocity Catalog

We estimate the mass density fluctuations power spectrum (PS) on large scales by applying a maximum likelihood technique to the peculiarvelocity data of the recently completed redshift-distance survey of early-type galaxies (ENEAR). The general results are in agreement with the high amplitude power spectra found from similar analysis of other independent all-sky catalogs of peculiar velocity data such as MARK III and SFI. For Lambda & Open CDM COBE normalized PS models, the best-fit parameters are confined by a contour approximately defined by Omega h^{1.3}=0.377+-0.08 and Omega h^{0.88}=0.517+-0.083, respectively. Gamma-shape models, free of COBE normalization, resultsin the weak constraint of $\Gamma \geq 0.17$ and in the rather stringent constraint of sigma_8 Omega^{0.6}=1.0+-0.25. All quoted uncertainties refer to 3-sigma confidence-level. The calculated PS is used as a prior for Wiener reconstruction of the density field at different resolutions and the three-dimensional velocity field within a volume of radius ~80 Mpc/h. All major structures in the nearby universe are recovered and are well matched to those predicted from all-sky redshift surveys.Comment: Submitted to MNRAS, 11 Pages, 9 figure

Thermoreversible gels for the encapsulation of macrophages: evaluation of polymer type on rheology and cytocompatibility

Thermoresponsive polymers have become a highly sought-after “smart material” due to their ability to modify their physical characteristics due to temperature changes. This research aimed to determine the biocompatibility of specific thermoreversible gels for immunocompetent cell models containing ImmuPHAGETM, human alveolar macrophage-like cells. Four polymers were selected based on their transition temperatures, including three commercially available pharmaceutical excipients, namely poloxamer 407, soluplus, and methylcellulose. The fourth system, poly(N-isopropyl acrylamide)-b-poly(ethylene oxide)-b-poly(N-isopropyl acrylamide), was synthesised in-house. Initially, the phase behaviour of these four polymers was evaluated visually by warming the polymer solutions and determining the state of the solution by vial inversion. Subsequently, a combination of rheological measurements was employed to compare the properties of these thermoreversible gels in culture media. The physical characterisation was followed by conducting cytocompatibility tests using human alveolar macrophages to assess their suitability as a scaffold for cell culture in vitro and to determine the cell response to different culturing environments. The study concluded that methylcellulose is the most promising and cost-effective material worth further exploration as a responsive matrix for immune cell encapsulation. Keywords: Thermoresponsive, Thermogelling, Alveolar macrophages, Foamy macrophages, immunocompetent in vitro models

Large-Scale Power Spectrum and Structures from the ENEAR Galaxy Peculiar Velocity Catalogue

We estimate the mass density fluctuations power spectrum (PS) on large scales by applying a maximum likelihood technique to the peculiar velocity data of the recently completed redshift—distance survey of early-type galaxies (hereafter ENEAR). Parametric cold dark matter (CDM)-like models for the PS are assumed, and the best-fitting parameters are determined by maximizing the probability of the model given the measured peculiar velocities of the galaxies, their distances and estimated errors. The method has been applied to CDM models with and without COBE normalization. The general results are in agreement with the high-amplitude power spectra found from similar analyses of other independent all-sky catalogue of peculiar velocity data such as MARK III and SFI, in spite of the differences in the way these samples were selected, the fact that they probe different regions of space and galaxy distances are computed using different distance relations. For example, at k = 0.1 h Mpc−1 the power spectrum value is P(k)Ω1.2 = (6.5 ± 3) × 103(h−1 Mpc)3 and η8 ≡ σ8Ω0.6 = 1.1−0.35+0.2; the quoted uncertainties refer to 3σ error level. We also find that, for ΛCDM and OCDM COBE-normalized models, the best-fitting parameters are confined by a contour approximately defined by Ω h1.3 = 0.377 ± 0.08 and Ω h0.88 = 0.517±0.083 respectively. Γ-shape models, free of COBE normalization, result in the weak constraint of Γ≥0.17 and in the rather stringent constraint of η8 = 1.0 ± 0.25. All quoted uncertainties refer to 3σ confidence level (c.l.). The calculated PS has been used as a prior for Wiener reconstruction of the density field at different resolutions and the three-dimensional velocity field within a volume of radius ≈80 h−1 Mpc. All major structures in the nearby Universe are recovered and are well matched to those predicted from all-sky redshift surveys. The robustness of these features has been tested with constrained realizations (CR). Analysis of the reconstructed three-dimensional velocity field yields a small bulk-flow amplitude (∼160±60 km s−1 at 60 h−1 Mpc) and a very small rms value of the tidal field (∼60 km s−1). The results give further support to the picture that most of the motion of the Local Group arises from mass fluctuations within the volume considered

Dendritic ion channel trafficking and plasticity.

Dendritic ion channels are essential for the regulation of intrinsic excitability as well as modulating the shape and integration of synaptic signals. Changes in dendritic channel function have been associated with many forms of synaptic plasticity. Recent evidence suggests that dendritic ion channel modulation and trafficking could contribute to plasticity-induced alterations in neuronal function. In this review we discuss our current knowledge of dendritic ion channel modulation and trafficking and their relationship to cellular and synaptic plasticity. We also consider the implications for neuronal function. We argue that to gain an insight into neuronal information processing it is essential to understand the regulation of dendritic ion channel expression and properties

Thermoreversible gels for the encapsulation of macrophages: evaluation of polymer type on rheology and cytocompatibility

© 2023 The Author(s). Published by the Royal Society of Chemistry. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Thermoresponsive polymers have become a highly sought-after “smart material” due to their ability to modify their physical characteristics due to temperature changes. This research aimed to determine the biocompatibility of specific thermoreversible gels for immunocompetent cell models containing ImmuPHAGETM, human alveolar macrophage-like cells. Four polymers were selected based on their transition temperatures, including three commercially available pharmaceutical excipients, namely poloxamer 407, soluplus, and methylcellulose. The fourth system, poly(N-isopropyl acrylamide)-b-poly(ethylene oxide)-b-poly(N-isopropyl acrylamide), was synthesised in-house. Initially, the phase behaviour of these four polymers was evaluated visually by warming the polymer solutions and determining the state of the solution by vial inversion. Subsequently, a combination of rheological measurements was employed to compare the properties of these thermoreversible gels in culture media. The physical characterisation was followed by conducting cytocompatibility tests using human alveolar macrophages to assess their suitability as a scaffold for cell culture in vitro and to determine the cell response to different culturing environments. The study concluded that methylcellulose is the most promising and cost-effective material worth further exploration as a responsive matrix for immune cell encapsulation. Keywords: Thermoresponsive, Thermogelling, Alveolar macrophages, Foamy macrophages, immunocompetent in vitro models.Peer reviewe

A hierarchy of voids: Much ado about nothing

We present a model for the distribution of void sizes and its evolution in the context of hierarchical scenarios of gravitational structure formation. We find that at any cosmic epoch the voids have a size distribution which is well-peaked about a characteristic void size which evolves self-similarly in time. This is in distinct contrast to the distribution of virialized halo masses which does not have a small-scale cut-off. In our model, the fate of voids is ruled by two processes. The first process affects those voids which are embedded in larger underdense regions: the evolution is effectively one in which a larger void is made up by the mergers of smaller voids, and is analogous to how massive clusters form from the mergers of less massive progenitors. The second process is unique to voids, and occurs to voids which happen to be embedded within a larger scale overdensity: these voids get squeezed out of existence as the overdensity collapses around them. It is this second process which produces the cut-off at small scales. In the excursion set formulation of cluster abundance and evolution, solution of the cloud-in-cloud problem, i.e., counting as clusters only those objects which are not embedded in larger clusters, requires study of random walks crossing one barrier. We show that a similar formulation of void evolution requires study of a two-barrier problem: one barrier is required to account for voids-in-voids, and the other for voids-in-clouds. Thus, in our model, the void size distribution is a function of two parameters, one of which reflects the dynamics of void formation, and the other the formation of collapsed objects.Comment: 23 pages, 9 figures, submitted to MNRA

Primeira Conferência Estadual de Ensino Primário em Santa Catarina: trabalhos manuais nas escolas primárias

Disponível em: http://histemat.com.br/index.php/HISTEMAT/article/view/156Diversas conferências mobilizadas por intelectuais da educação tomam espaços motivadas por movimentos reformistas em âmbito estadual e nacional na década de 1920 no Brasil. Este artigo intenta analisar a tese oficial n. 06 presente nos Anais da Primeira Conferência Estadual de Ensino Primário ocorrida em Santa Catarina em 1927 que tratou especificamente dos trabalhos manuais nas escolas primárias e complementares. Fundamentado nos pressupostos teóricos da História Cultural, a análise levou em conta referências da história, história da educação, bem como da história da educação matemática. Como resultado desta investigação apurou-se recomendações e discussões pelos participantes da Conferência sobre os conteúdos relacionados aos trabalhos manuais. Estes revelam aproximações da natureza do ensino do saber matemático rudimentar, se articulam com problemas da vida e também instrumentalizam os alunos para uma fase pós-escola