Antisymmetric Tensor Fields in Randall Sundrum Thick Branes

In this article we study the issue of localization of the three-form field in a Randall-Sundrum-like scenario. We simulate our membrane by kinks embedded in D=5, describing the usual case (not deformed) and new models coming from a specific deformation procedure. The gravitational background regarded includes the dilaton contribution. We show that we can only localize the zero-mode of this field for a specific range of the dilaton coupling, even in the deformed case. A study about resonances is presented. We use a numerical approach for calculations of the transmission coefficients associated to the quantum mechanical problem. This gives a clear description of the physics involved in the model. We find in this way that the appearance of resonances is strongly dependent on the coupling constant. We study the cases $p=1,3$ and 5 for $\alpha=-1.75$ and $\alpha=-20$. The first value of $\alpha$ give us one resonance peak for $p=1$ and no resonances for $p=3,5$. The second value of $\alpha$ give us a very rich structure of resonances, with number deppending on the value of $p$.Comment: 7 pages, 3 figure

3D black holes on a 2-brane in 4D Minkowski space

We investigate three-dimensional black hole solutions in the realm of pure and new massive gravity in 2+1 dimensions induced on a 2-brane embedded in a flat four-dimensional spacetime. There is no cosmological constant neither on the brane nor on the four-dimensional bulk. Only gravitational fields are turned on and we indeed find vacuum solutions as black holes in 2+1 dimensions even in the absence of any cosmological solution. There is a crossover scale that controls how far the three- or four-dimensional gravity manifests on the 2-brane. Our solutions also indicate that local BTZ and SdS_3 solutions can flow to local four-dimensional Schwarzschild like black holes, as one probes from small to large distances, which is clearly a higher dimensional manifestation on the 2-brane. This is similar to the DGP scenario where the effects of extra dimensions for large probed distances along the brane manifest.Comment: 10 pages, 5 figures, to appear in PL

Self-Interactions in the Spacetime of a Scalar-Tensor Cosmic String

We study the effect of the geometry and topology of a scalar-tensor cosmic string space-time on the electric and magnetic fields of line sources. It is shown that the dilatonic coupling of the gravity induces effects along the string comparable to a current flow allowing for forbidden regions near the string.Comment: 7 pages, 2 figures. Revised version to appear in the Phys. Lett.

Prevalence and risk factors of inadequate medicine home storage: a community-based study

OBJECTIVE: Assess the extent of inadequate home storage of medicines andidentify important risk factors. METHODS: A cross-sectional survey based on a probability sample in the community, conducted in 267 households in Cuité, State of Paraíba, Northeast Brazil, in 2014. Logistic regression was used to study the risk factors. RESULTS: The prevalence of households with inadequate storage was 76.0%. Problems with storage include direct exposure to sunlight in 10.9% of households, the presence of dust in 23.6%, and storage within reach of children in 76.0%. Medications no longer used are usually disposed of into the environment in 92.1% of households. Inadequate storage is more likely when home organization of medications is the responsibility of a male subject (OR = 1.729) or an older person (OR = 1.029), when out of date medicines are found (OR = 2.963), and in households with no children (OR = 2.088). CONCLUSIONS: Physicians and pharmacists should advise patients on how to adequately store medicines at home, especially when the person in charge of medications is a male or an older adult, and if there are no children in the household

Brane Cosmology in the Background of D-Brane with NS B Field

We study the cosmological evolution of the four-dimensional universe on the probe D3-brane in geodesic motion in the curved background of the source Dp-brane with non-zero NS B field. The Friedman equations describing the expansion of the brane universe are obtained and analyzed for various limits. We elaborate on corrections to the cosmological evolution due to nonzero NS B field.Comment: 13 pages, LaTeX, revised version with minor corrections to appear in Phys. Rev.

A Transfer Matrix Method for Resonances in Randall-Sundrum Models

In this paper we discuss in detail a numerical method to study resonances in membranes generated by domain walls in Randall-Sundrum-like scenarios. It is based on similar works to understand the quantum mechanics of electrons subject to the potential barriers that exist in heterostructures in semiconductors. This method was used recently to study resonances of a three form field and lately generalized to arbitrary forms. We apply it to a lot of important models, namely those that contain the Gauge, Gravity and Spinor fields. In many cases we find a rich structure of resonances which depends on the parameters involved.Comment: 25 pages, 17 figure

Disformal Inflation

We show how short inflation naturally arises in a non-minimal gravity theory with a scalar field without any potential terms. This field drives inflation solely by its derivatives, which couple to the matter only through the combination $\bar g_{\mu\nu} = g_{\mu\nu} - \frac{1}{m^4} \partial_\mu \phi \partial_\nu \phi$. The theory is free of instabilities around the usual Minkowski vacuum. Inflation lasts as long as $\dot \phi^2 > m^4$, and terminates gracefully once the scalar field kinetic energy drops below $m^4$. The total number of e-folds is given by the initial inflaton energy $\dot \phi_0^2$ as ${\cal N} \simeq \frac13 \ln(\frac{\dot \phi_0}{m^2})$. The field $\phi$ can neither efficiently reheat the universe nor produce the primordial density fluctuations. However this could be remedied by invoking the curvaton mechanism. If inflation starts when $\dot \phi^2_0 \sim M^4_P$, and $m \sim m_{EW} \sim TeV$, the number of e-folds is ${\cal N} \sim 25$. Because the scale of inflation is low, this is sufficient to solve the horizon problem if the reheating temperature is T_{RH} \ga MeV. In this instance, the leading order coupling of $\phi$ to matter via a dimension-8 operator $\frac{1}{m^4}\partial_\mu \phi \partial_\nu \phi ~ T^{\mu\nu}$ would lead to fermion-antifermion annihilation channels $f\bar f \to \phi \phi$ accessible to the LHC, while yielding very weak corrections to the Newtonian potential and to supernova cooling rates, that are completely within experimental limits.Comment: 19 pages, latex, 3 .eps figures, v2: references added, to appear in PL

Piancó-Alto Brígida branching system of orogens (PE-PB-CE), Tectonic regionalization and geochronology

O Sistema de Dobramentos Piancó-Alto Brígida (SPAB) situa-se na porção central a centro-ocidental da Zona Transversal, da Província Borborema, nos Estados da Paraíba e do Pernambuco e em parte do Estado do Ceará. Trata-se do produto de um desenvolvimento orogenético na passagem Criogeniano-Ediacarano (630–580 Ma, acresção seguida de colisão), levando à inversão vigorosa de uma pretérita bacia de sedimentação marinha costeira. O limite ao norte é marcado pelo Lineamento de Patos e o ao sul é balizado pelo Lineamento Pernambuco. O contexto paleogeográfico (e litoestratigráfico) original é de reconstituição difícil devido aos eventos de deformação (pelo menos três fases) e metamorfismo, lateralmente variável de muito baixo, baixo a médio graus, seguidos de uma importante fase de tectônica extrusional tardia. O SPAB se encontra hoje geológico-geograficamente ramificado em diferentes faixas, separadas por alguns basement inliers, paleoproterozoicos/“terrenos”, expressivos em área e importantes partícipes dos eventos de deformação. Os principais litotipos presentes no SPAB se enquadram nas típicas assembleias quartzito-pelito-calcário (QPC) com a característica primordial da grande ritmicidade. Os gradientes metamórficos são de muito baixo, baixo e médio graus (nesse último caso, para o sul, faixa do interior de Pernambuco, “Supergrupo Salgueiro”). Nas zonas proximais dos contatos com o embasamento, consoante a linhas de falhas importantes, são registrados brechas e conglomerados polimícticos, arenitos imaturos, metagrauvacas e metacórseos (Formação Olhos d’Água). Embora haja várias contribuições, de diversas fontes, ao longo dos últimos 50 anos, em diferentes tempos e propósitos, uma discriminação da litoestratigráfica satisfatória ainda não foi possível. De sorte que todos os termos litoestratigráficos devem ser encarados como informais e provisórios. Múltiplos trabalhos de reconhecimento em geocronologia foram realizados aleatoriamente nesse sistema nas The Piancó-Alto Brígida branching system of orogens (SPAB) is in the central and center-western part of the Transversal Zone, of Borborema Province, in the states of Paraíba, Pernambuco and Ceará. It is a final tectonic product of an orogenetic development during Cryogenian-Ediacarian periods. The original paleogeographic (and lithostratigraphic) scenery is of difficult reconstitution due to tectonic events (at least three different phases of folding), with lateral variations of the metamorphism’s degree from very low to low grade. These events were followed by an important final phase of escape tectonics (extrusion). Today, the SPAB is geographically branched into different fold belts, bounded by some Paleoproterozoic basement inliers that are expressive both in area and participation in the regional deformation. The main lithological assemblages present in the SPAB belts may be classified as part of typical QPC (quartzite-pelite-carbonate) assemblages, with a striking characteristic of remarkable rhythmicity, as well as the metamorphic gradient very low to low grades up to medium grade (to the belt of the interior of Pernambuco “Supergurpo Salgueiro”). Along the zones near the contacts with the basement (following important fault lines) polymictic breccias and conglomerates, immature sandstones and arkoses (“Formação Olhos d´Água”) are recorded. Even though there are many sources of scientific contributions on this subject in the last 50 years, at different times and purposes, a satisfactory lithostratigraphic classification was not possible. So all the lithostratigraphic terminology (here discussed) should be faced as informal and provisory. Many reconnaissance projects of geochronology have been done along the two last decades. In the last years, a systematic program of geochronological research (Sm-Nd and U-Pb methods) has been developed trying to&nbsp

Human-based nanocomposite cryogels for hemostatic and wound healing applications

In trauma surgery, a fast and effective hemostatic agent is crucial to prevent death. The current used hemostatic sponges are highly effective in stopping the hemorrhages, however they have a limited stability, shape memory, and biological functionality to induce an efficient regenerative healing after injury. Blood derivatives have attracted great attention as an inexpensive milieu of bioactive molecules (e.g., growth factors, cytokines), self-assembling scaffolding proteins (e.g., fibrinogen, fibronectin, vitronectin), and antimicrobial peptides (e.g., platelet factor-4) that have the ability to enhance angiogenesis, stem cell recruitment, and tissue regeneration. Among those, platelet lysate (PL) has attracted great attention as a milieu of supra-physiological doses of biomolecules that can be easily standardized. However, the current PL scaffolds showed limited stability and weak mechanical strength, which severely limits its performance as a bioinstructive and hemostatic biomaterial. Herein, we propose the use of aldehyde-functionalized CNC (a-CNC) that will be crosslinked through reversible Schiff base bonds established with the amine groups of PL proteins to produce a stable hemostatic cryogel for wound healing applications.EU’s H2020 programme for grant agreement 706996 and 739572 - The Discoveries CTR; FCT for SFRH/BPD/112459/2015, PD/BD/113807/2015, FOOD4CELLS (PTDC/CTM-BIO/4706/2014-POCI-01- 0145- FEDER 016716) and project NORTE-01-0145- FEDER-000021