Biomechanics of the Cornea Assessed by the CorVis ST ® Device: a Numerical Approach

To evaluate by means of finite element modeling the influence of tissue properties of the cornea on its deformation response when an air jet is applied onto its surface and, according to this, to discuss the clinical interpretation of these measurements in terms of corneal biomechanical behaviour

Effect of nest composition, experience and nest quality on nest-building behaviour in the Bonelli's Eagle.

In bi-parentally built nests, there is evidence to suggest that nests are extended phenotypic signals that accurately indicate the quality of the building parent/s. Raptors often use a variety of materials to build their nests (natural, such as branches, but also non-natural objects), presumably due to their insulating properties, their suitability to advertise occupancy of the nest, and to decrease pathogen and parasite loads. However, in raptors where both sexes collaborate in nest construction, it is unclear whether nest building (taking the amount of material carried to the nest as the potential predictor) is an indicator of parental quality, and whether the effort expended by both sexes could constitute an honest signal of parental quality to their partners. Between 2011 and 2016, we monitored 16 nests of Bonelli's Eagles (Aquila fasciata), and we examined data on sex, type of material brought to the nest, breeding experience, nest quality, timing, and nest-building investment prior to egg-laying from 32 identifiable Bonelli's Eagles during the pre-laying period to investigate the relative contribution of the sexes to the amount of nest material gathered. Our results indicate that sex is not a determining factor in nest-building effort, and that females did not increase their parental effort in response to the male's contribution, and supply of materials did not increase during the pre-laying period. In contrast, our models showed that: (1) the type of material supplied to the nest by both sexes varied significantly throughout the pre-laying period and (2) nest-building effort was determined by individual experience and nest quality. Therefore, our study suggests that male nest-building behaviour and investment by Bonelli's Eagles cannot be considered as an extended phenotypic signal. The differential use of hard and green material by both sexes in the early and late stages of nest-building period, and the fact that the more experienced individuals contributed a larger amount of material on low quality nests, are discussed in the contexts of signaling nest occupancy to conspecifics and competitors and the decrease of ectoparasite loads during the pre-laying period

Association of Polymorphisms in the Interleukin 6 Receptor Complex with Obesity and Hyperandrogenism

10 pages, 5 tables.Objective: Interleukin-6 (IL-6), is an inflammatory cytokine that may influence the pathogenesis of obesity and hyperandrogenism. IL-6 exerts its actions through a heterodimeric receptor consisting of two membrane-bound glycoproteins: an 80-kDa IL-6 binding unit (IL6R-alpha) and a 130-kDa IL-6 signal transducer (gp130). Genetic variability at these loci might contribute to explain the development of obesity and hyperandrogenism. Research Methods and Procedures: We have evaluated the possible association of several polymorphisms in the IL6R-alpha and gp130 genes with obesity and/or hyperandrogenism in a case-control study involving 143 hyperandrogenic patients and 45 healthy women from Spain. Results: A microsatellite CA-repeat polymorphism in the IL6R-alpha locus was associated with obesity. The frequency of the common 149-bp allele was markedly increased in obese women compared with controls when considering patients and controls as a whole (0.41 vs. 0.29, chi2 = 17.085, p < 0.050). On the other hand, the uncommon Arg148 allele of the Gly148Arg polymorphism in the gp130 gene was more frequent in controls compared with hyperandrogenic patients (0.17 vs. 0.08, chi2 = 5.605, p = 0.026). Controls carrying Arg148 alleles had lower 11-deoxycortisol and 17-hydroxyprogesterone concentrations, a lower response of androstenedione to 1–24 adrenocorticotropin, and an almost significant decrease in free testosterone levels, suggesting that Arg148 alleles in the gp130 gene have a protective effect against androgen excess and adrenal hyperactivity. Discussion: Polymorphisms in the gp130 and IL6R-alpha loci influence hyperandrogenism and obesity, respectively. Our present results further suggest that proinflammatory genotypes are involved in the pathogenesis of these common metabolic disorders.This work was supported by grants from the Consejería de Educación, Comunidad de Madrid, Spain (Proyectos 08.6/0022/1998, 08.6/0024.2/2000, and 08.6/0010/2001), and from the Fondo de Investigación Sanitaria, Ministerio de Sanidad y Consumo, Spain (Proyectos FIS 00/0414 and 02/0741 to H.F.E.-M.Peer reviewe

Theoretical and experimental nucleation and growth of precipitates in a medium carbon–vanadium steel

Using the general theory of nucleation, the nucleation period, critical radius, and growth of particles were determined for a medium carbon V-steel. Several parameters were calculated, which have allowed the plotting of nucleation critical time vs. temperature and precipitate critical radius vs. temperature. Meanwhile, an experimental study was performed and it was found that the growth of precipitates during precipitation obeys a quadratic growth equation and not a cubic coalescence equation. The experimentally determined growth rate coincides with the theoretically predicted growth ratePeer ReviewedPostprint (author's final draft

Segmentación y registración de imágenes 3d

La generación de modelos de superficie, herramientas que facilitan el manejo de información 3D, técnicas de adquisición, generación y visualización de modelos 3D, entre otros, han venido a conformar la Estereología. El tratamiento de imágenes 3D, segmentación, generación de modelos numéricos de superficies, y en particular en imágenes médicas, registración, i.e. integración del Atlas Cerebral u otro atlas anatómicos con las imágenes, requiere el conocimiento de herramientas conceptuales y algorítmicas útiles en muchas otras aplicaciones 3D.Eje: VisualizaciónRed de Universidades con Carreras en Informática (RedUNCI

Segmentación y registración de imágenes 3d

La generación de modelos de superficie, herramientas que facilitan el manejo de información 3D, técnicas de adquisición, generación y visualización de modelos 3D, entre otros, han venido a conformar la Estereología. El tratamiento de imágenes 3D, segmentación, generación de modelos numéricos de superficies, y en particular en imágenes médicas, registración, i.e. integración del Atlas Cerebral u otro atlas anatómicos con las imágenes, requiere el conocimiento de herramientas conceptuales y algorítmicas útiles en muchas otras aplicaciones 3D.Eje: VisualizaciónRed de Universidades con Carreras en Informática (RedUNCI

Segmentación y registración de imágenes 3d

La generación de modelos de superficie, herramientas que facilitan el manejo de información 3D, técnicas de adquisición, generación y visualización de modelos 3D, entre otros, han venido a conformar la Estereología. El tratamiento de imágenes 3D, segmentación, generación de modelos numéricos de superficies, y en particular en imágenes médicas, registración, i.e. integración del Atlas Cerebral u otro atlas anatómicos con las imágenes, requiere el conocimiento de herramientas conceptuales y algorítmicas útiles en muchas otras aplicaciones 3D.Eje: VisualizaciónRed de Universidades con Carreras en Informática (RedUNCI

Mechanistic understanding of the behavior of diuron in the adsorption from water onto activated carbon

The adsorption of diuron from aqueous phase by activated carbon has been analyzed from a molecular point of view thanks to a computational approach based on COSMO-RS methodology, with the aim of providing a mechanistic explanation of the experimental results. The adsorption experiments were carried out at different pH values (3-7) and temperatures (15-45 °C) using an activated carbon prepared by chemical activation of grape seeds. The most relevant characteristics of the adsorption of diuron were the increase of diuron uptake with temperature and the occurrence of multilayer adsorption at high equilibrium concentrations. Likewise, the contribution of cooperative adsorption was also found to increase with temperate, as shown by the change of the isotherm pattern from L-3 type (Giles classification) at 15 °C to S-3 at 45 °C. The formation of multilayer and the contribution of cooperative adsorption were not observed at the highest pH studied The results obtained from the computational approach were consistent with the trends shown by the experimental data. The molecular and thermodynamic properties of the solvent-adsorbate-adsorbent system were estimated using the quantum-chemical COSMO-RS method. Thus, the increase in diuron uptake at increasing temperature was ascribed to a higher population of diuron planar conformers, whose affinity for activated carbon is higher as evaluated in terms of the activated carbon/water partition coefficient. COSMO-RS simulations predicted strong interaction among diuron molecules due to the amphoteric character of the molecule. Likewise, the formation of clusters was found to be especially favored from a thermodynamic point of view in the case of planar conformers adsorbed on activated carbon, which supports the occurrence of cooperative adsorption and the formation of a multilayerWe greatly appreciate financial support from the Spanish MCYT (CTQ2009-09983 and CSD2006-44) and CAM (REMTAVARES S-2009/AMB-1588

Coupled Biomechanical Response of the Cornea Assessed by Non-Contact Tonometry. A Simulation Study

The mechanical response of the cornea subjected to a non-contact air-jet tonometry diagnostic test represents an interplay between its geometry, the corneal material behavior and the loading. The objective is to study this interplay to better understand and interpret the results obtained with a non-contact tonometry test. A patient-specific finite element model of a healthy eye, accounting for the load free configuration, was used. The corneal tissue was modeled as an anisotropic hyperelastic material with two preferential directions. Three different sets of parameters within the human experimental range obtained from inflation tests were considered. The influence of the IOP was studied by considering four pressure levels (10–28 mmHg) whereas the influence of corneal thickness was studied by inducing a uniform variation (300–600 microns). A Computer Fluid Dynamics (CFD) air-jet simulation determined pressure loading exerted on the anterior corneal surface. The maximum apex displacement showed a linear variation with IOP for all materials examined. On the contrary, the maximum apex displacement followed a cubic relation with corneal thickness. In addition, a significant sensitivity of the apical displacement to the corneal stiffness was also obtained. Explanation to this behavior was found in the fact that the cornea experiences bending when subjected to an air-puff loading, causing the anterior surface to work in compression whereas the posterior surface works in tension. Hence, collagen fibers located at the anterior surface do not contribute to load bearing. Non-contact tonometry devices give useful information that could be misleading since the corneal deformation is the result of the interaction between the mechanical properties, IOP, and geometry. Therefore, a non-contact tonometry test is not sufficient to evaluate their individual contribution and a complete in-vivo characterization would require more than one test to independently determine the membrane and bending corneal behavior.The research leading these results has received funding from the European Union’s Seven Framework Program managed by REA Research Executive agency http://ec.europa.eu/research/rea (FP7/2007-2013) under Grant Agreement n° FP7-SME-2013 606634 and the Spanish Ministry of Economy and Competitiveness (DPI2011-27939-C02-01)

The salivary gland transcriptome of the neotropical malaria vector Anopheles darlingi reveals accelerated evolution of genes relevant to hematophagy

BackgroundMosquito saliva, consisting of a mixture of dozens of proteins affecting vertebrate hemostasis and having sugar digestive and antimicrobial properties, helps both blood and sugar meal feeding. Culicine and anopheline mosquitoes diverged ~150 MYA, and within the anophelines, the New World species diverged from those of the Old World ~95 MYA. While the sialotranscriptome (from the Greek sialo, saliva) of several species of the Cellia subgenus of Anopheles has been described thoroughly, no detailed analysis of any New World anopheline has been done to date. Here we present and analyze data from a comprehensive salivary gland (SG) transcriptome of the neotropical malaria vector Anopheles darlingi (subgenus Nyssorhynchus).ResultsA total of 2,371 clones randomly selected from an adult female An. darlingi SG cDNA library were sequenced and used to assemble a database that yielded 966 clusters of related sequences, 739 of which were singletons. Primer extension experiments were performed in selected clones to further extend sequence coverage, allowing for the identification of 183 protein sequences, 114 of which code for putative secreted proteins.ConclusionComparative analysis of sialotranscriptomes of An. darlingi and An. gambiae reveals significant divergence of salivary proteins. On average, salivary proteins are only 53% identical, while housekeeping proteins are 86% identical between the two species. Furthermore, An. darlingi proteins were found that match culicine but not anopheline proteins, indicating loss or rapid evolution of these proteins in the old world Cellia subgenus. On the other hand, several well represented salivary protein families in old world anophelines are not expressed in An. darlingi