Pullback attractors for a singularly nonautonomous plate equation

We consider the family of singularly nonautonomous plate equation with structural damping $$u_{tt} + a(t,x)u_{t} + (- \Delta) u_{t} + (-\Delta)^{2} u + \lambda u = f(u),$$ in a bounded domain $\Omega \subset \R^n$, with Navier boundary conditions. When the nonlinearity $f$ is dissipative we show that this problem is globally well posed in $H^2_0(\Omega) \times L^2(\Omega)$ and has a family of pullback attractors which is upper-semicontinuous under small perturbations of the damping $a$

Multiscale model for the effects of adaptive immunity suppression on the viral therapy of cancer

Oncolytic virotherapy - the use of viruses that specifically kill tumor cells - is an innovative and highly promising route for treating cancer. However, its therapeutic outcomes are mainly impaired by the host immune response to the viral infection. In the present work, we propose a multiscale mathematical model to study how the immune response interferes with the viral oncolytic activity. The model assumes that cytotoxic T cells can induce apoptosis in infected cancer cells and that free viruses can be inactivated by neutralizing antibodies or cleared at a constant rate by the innate immune response. Our simulations suggest that reprogramming the immune microenvironment in tumors could substantially enhance the oncolytic virotherapy in immune-competent hosts. Viable routes to such reprogramming are either in situ virus-mediated impairing of CD$8^+$ T cells motility or blockade of B and T lymphocytes recruitment. Our theoretical results can shed light on the design of viral vectors or new protocols with neat potential impacts on the clinical practice.Comment: 14 pages, 4 figure

The antinociceptive effect of electroacupuncture at different depths of acupoints and under the needling surface

<p>Abstract</p> <p>Background</p> <p>The stimulation of acupoints along the meridians, but not the non-acupoints outside of the meridians, produces analgesia. Although the acupoint is defined at the body surface, the exact location of the acupoints is not known. This study aims to examine whether the intensity and duration of the analgesic effect of electroacupuncture (EA) at the <it>Zusanli </it>(ST36) and <it>Sanynjiao </it>acupoints (SP6) change according to the depth of the stimulation.</p> <p>Methods</p> <p>Ninety-six male Wistar rats classified as responders were arbitrarily allocated into 16 groups of six rats each. Six groups received EA with uninsulated acupuncture needles (type I) or needles that were immersed in varnish and had the varnish circularly peeled 0.2 mm from the tip (type II), 0.2 mm at 3 mm (type III) or 5 mm (type IV) from the tip, or 0.2 mm at 5 and 1 mm from the tip (type V), or EA sham for 20 min. Five groups received injection of formalin into the acupoint bilaterally at 5 mm or 1 mm deep into ST36, 5 mm below ST36 but inserting the needle at 45° to the skin surface, or 5 mm deep into non-acupoints. The remaining groups received intraplantar injection of saline, 1% or 2.5% formalin. The analgesic effects were measured by the rat tail-flick test.</p> <p>Results</p> <p>The bilateral stimulation of ST36 and SP6 by uninsulated or insulated needles produced analgesia in the rat tail-flick test. The stronger and longer lasting effects occurred after EA with the types I and V needles, or injection of formalin 5 mm deep into ST36. The remaining needles produced weaker and shorter lasting effects. Slow analgesic effect also occurred after formalin injection at 1 mm or 5 mm below ST36 by inserting the needle at 45° to the skin surface.</p> <p>Conclusion</p> <p>The experimental results suggest that the efficacy of the EA stimulation depends on the spatial distribution of the current density under the needling surface rather than only the acupoint or the depth of needling.</p

High performance reduced order modeling techniques based on optimal energy quadrature: application to geometrically non-linear multiscale inelastic material modeling

A High-Performance Reduced-Order Model (HPROM) technique, previously presented by the authors in the context of hierarchical multiscale models for non linear-materials undergoing infinitesimal strains, is generalized to deal with large deformation elasto-plastic problems. The proposed HPROM technique uses a Proper Orthogonal Decomposition procedure to build a reduced basis of the primary kinematical variable of the micro-scale problem, defined in terms of the micro-deformation gradient fluctuations. Then a Galerkin-projection, onto this reduced basis, is utilized to reduce the dimensionality of the micro-force balance equation, the stress homogenization equation and the effective macro-constitutive tangent tensor equation. Finally, a reduced goal-oriented quadrature rule is introduced to compute the non-affine terms of these equations. Main importance in this paper is given to the numerical assessment of the developed HPROM technique. The numerical experiments are performed on a micro-cell simulating a randomly distributed set of elastic inclusions embedded into an elasto-plastic matrix. This micro-structure is representative of a typical ductile metallic alloy. The HPROM technique applied to this type of problem displays high computational speed-ups, increasing with the complexity of the finite element model. From these results, we conclude that the proposed HPROM technique is an effective computational tool for modeling, with very large speed-ups and acceptable accuracy levels with respect to the high-fidelity case, the multiscale behavior of heterogeneous materials subjected to large deformations involving two well-separated scales of length.Peer ReviewedPostprint (author's final draft

Sett Use, Density and Breeding Phenology of Badgers in Mediterranean Agro-Sylvo-Pastoral Systems

Carnivores social organization varies widely, from strongly social to solitary predators. European badgers are facultative social carnivores that also shows a geographical variation in social structure. These patterns derive mainly from central/west European regions, with an underrepresentation of Mediterranean populations that face different conservation challenges, especially regarding group composition, sett use patterns and breeding phenology. We addressed these traits topics for a population inhabiting a Portuguese agro-silvo-pastoral system. Based on monthly monitoring of 34 setts and continuous camera-trapping surveys of 12, we showed that setts surrounded by diversified vegetation and located in sandy sites are more used, a pattern probably linked to food availability and ease of sett excavation and maintenance, respectively. Badgers followed a general pattern regarding group size (2–4 adults), but showed an intermediate population density (0.49–0.73 badgers/km2), with values higher than those estimated for other Mediterranean environments, but lower than for central-western populations. This, together with the breeding (November/January) and cub emergence (1.8 cubs/sett; March/April) periods, indicates an ecological adaptation to the landscape context, where human-related resources and mild environmental conditions allow badger to reach higher densities than in many southern populations, and to reproduce earlier than their northern counterparts.Understanding carnivores social structure variation is pivotal for properly addressing conservation challenges and solutions. The European badgers is a social carnivore for which most of the available information regarding how this species is socially organized derives from central west populations. This article describes the group composition, den use patterns and breeding phenology of a Mediterranean population of badgers. We showed that badger live in low density, in relatively small groups, composed by 2–4 adult animals and ca. 2 cubs, born in winter. These patterns, representing a variation of what was described for other populations, show that badgers take advantage of the landscape context, where human-related resources and mild environmental conditions allow badger to reach higher densities than in many southern populations, and to reproduce earlier than their northern counterparts.info:eu-repo/semantics/publishedVersio

AtPIN: Arabidopsis thaliana Protein Interaction Network

<p>Abstract</p> <p>Background</p> <p>Protein-protein interactions (PPIs) constitute one of the most crucial conditions to sustain life in living organisms. To study PPI in Arabidopsis thaliana we have developed AtPIN, a database and web interface for searching and building interaction networks based on publicly available protein-protein interaction datasets.</p> <p>Description</p> <p>All interactions were divided into experimentally demonstrated or predicted. The PPIs in the AtPIN database present a cellular compartment classification (C³) which divides the PPI into 4 classes according to its interaction evidence and subcellular localization. It has been shown in the literature that a pair of genuine interacting proteins are generally expected to have a common cellular role and proteins that have common interaction partners have a high chance of sharing a common function. In AtPIN, due to its integrative profile, the reliability index for a reported PPI can be postulated in terms of the proportion of interaction partners that two proteins have in common. For this, we implement the Functional Similarity Weight (FSW) calculation for all first level interactions present in AtPIN database. In order to identify target proteins of cytosolic glutamyl-tRNA synthetase (Cyt-gluRS) (AT5G26710) we combined two approaches, AtPIN search and yeast two-hybrid screening. Interestingly, the proteins glutamine synthetase (AT5G35630), a disease resistance protein (AT3G50950) and a zinc finger protein (AT5G24930), which has been predicted as target proteins for Cyt-gluRS by AtPIN, were also detected in the experimental screening.</p> <p>Conclusions</p> <p>AtPIN is a friendly and easy-to-use tool that aggregates information on <it>Arabidopsis thaliana </it>PPIs, ontology, and sub-cellular localization, and might be a useful and reliable strategy to map protein-protein interactions in Arabidopsis. AtPIN can be accessed at <url>http://bioinfo.esalq.usp.br/atpin</url>.</p

SPATIAL AND TEMPORALVARIATION OF DISSOLVED INORGANIC NUTRIENTS, AND CHLOROPHYLL-α IN A TROPICAL ESTUARY IN NORTHEASTERN BRAZIL: DYNAMICS OF NUTRIENT REMOVAL

Monthly sampling campaigns were carried out between February 2010 and January 2011 to evaluate the spatial and temporal distribution of nutrients (ammonium, nitrite, nitrate, dissolved organic nitrogen, phosphate, dissolved organic phosphorus and silicate) and chlorophyll-α along a salinity gradient in the tropical Cachoeira River estuary, subject to the untreated effluents of a sewage treatment plant (STP). During the study period the lowest and highest river discharge occurred in February and April 2010, respectively. High river outflow promoted increased concentrations of inorganic nitrogen and silicate but did not affect the concentration of phosphate. Based on the chlorophyll-α concentration the estuary may be classified as eutrophic / hypereutrophic in its inner portion and mesotrophic in the lower region. The inner portion is more affected by the nutrient load carried out by the river and STP, while dilution by seawater contributed to the reduction of the nutrient concentrations in the lower reaches of the estuary. The results indicate that nutrient uptake by the phytoplankton is the most effective dissolved inorganic nutrient removal processes, especially for phosphate. Mixing diagrams suggest that the coupling of nitrification and denitrification processes is also responsible for the elimination of nitrogen from this ecosystem.Campanhas de amostragens mensais foram realizadas entre fevereiro de 2010 e janeiro de 2011 para avaliar a distribuição espacial e temporal de nutrientes (amônia, nitrito, nitrato, nitrogênio orgânico dissolvido, fosfato, fósforo orgânico dissolvido e silicato) e clorofila-α, ao longo do gradiente de salinidade no estuário tropical do Rio Cachoeira. Este estuário é sujeito aos efluentes de esgotos não tratados de uma estação de tratamento de esgoto (ETE). No período estudado a maior e menor vazão do rio ocorreram em fevereiro e abril de 2010, respectivamente. A alta vazão do rio promoveu aumento das concentrações de nitrogênio inorgânico e silicato, mas não afetou as concentrações de fosfato. Baseado nas concentrações de clorofila-α, o estuário pode ser classificado como eutrófico/hipereutrófico na porção interna e mesotrófico na região externa. A porção interna é mais afetada pela carga de nutrientes do rio e da ETE, enquanto a diluição pela água marinha contribuiu para diminuir as concentrações de nutrientes na porção externa. Os resultados indicam que a absorção de nutrientes pelo fitoplâncton é o processo mais eficiente na remoção desses nutrientes, especialmente do fosfato. No entanto, os diagramas de mistura sugerem que a nitrificação e denitrificação acopladas no rio também são responsáveis pela eliminação do nitrogênio do ecossistema

Albumin versus crystalloid solutions in patients with the acute respiratory distress syndrome: a systematic review and meta-analysis

INTRODUCTION: In patients with acute respiratory distress syndrome (ARDS) fluid therapy might be necessary. The aim of this systematic review and meta-analysis is to determine the effects of colloid therapy compared to crystalloids on mortality and oxygenation in adults with ARDS. METHODS: Randomized controlled trials (RCTs) were identified through a systematic literature search of MEDLINE, EMBASE, CENTRAL and LILACS. Articles published up to 15(th) February 2013 were independently screened, abstracted, and assessed (Cochrane Risk of Bias Tool) to provide evidence-based therapy recommendations. RCTs were eligible if they compared colloid versus crystalloid therapy on lung function, inflammation, damage or mortality in adults with ARDS. Primary outcome parameters were respiratory mechanics, gas exchange lung inflammation and damage as well as hospital mortality. Kidney function, need for renal replacement therapy, hemodynamic stabilization and intensive care unit (ICU) length of stay served as secondary outcomes. RESULTS: A total of 3 RCTs out of 4130 potential trials found in the databases were selected for qualitative and quantitative analysis totaling 206 patients who received either albumin or saline. Overall risk of bias was unclear to high in the identified trials. Calculated pooled risk of death was not statistically significant (albumin 34 of 100 (34.0%) versus 40 of 104 (38.5%), relative risk (RR) = 0.89, 95% confidence interval (CI) 0.62 to 1.28, P = 0.539). Weighted mean difference (WMD) in PaO(2)/FiO(2) (mmHg) improved in the first 48 hours (WMD = 62, 95% CI 47 to 77, P <0.001, I(2) = 0%) after therapy start and remained stable after 7 days (WMD = 20, 95% CI 4 to 36, P = 0.017, I(2) = 0%). CONCLUSIONS: There is a high need for RCTs investigating the effects of colloids in ARDS patients. Based on the findings of this review, colloid therapy with albumin improved oxygenation but did not affect mortality