Numerical study of turbulence models in the computation of blood flow in cannulas

In recent years, CFD has become an increasingly used tool in the design of blood-based devices. However, the estimation of red blood cells damage (hemolysis) remains a very important challenge due to the complex rheology of blood and the turbulence present in most pumping devices. The objective of this study was to identify an appropriate turbulence model suitable for predicting hemolysis in Hemodialysis cannula. Several modern turbulence models were evaluated in comparison to Direct Numerical Simulation (DNS), which was used as the gold standard. The fluid dynamics in the cannula was modeled as a coaxial jet in which Reynolds’ number approached 2800. Based on comparison of velocity and stress time-averaged profiles, the Shear Stress Transport (SST) model with Gamma-Theta transition was identified as an optimal compromise between accuracy and computational cost

Predicting Phenotypic Diversity and the Underlying Quantitative Molecular Transitions

During development, signaling networks control the formation of multicellular patterns. To what extent quantitative fluctuations in these complex networks may affect multicellular phenotype remains unclear. Here, we describe a computational approach to predict and analyze the phenotypic diversity that is accessible to a developmental signaling network. Applying this framework to vulval development in C. elegans, we demonstrate that quantitative changes in the regulatory network can render ~500 multicellular phenotypes. This phenotypic capacity is an order-of-magnitude below the theoretical upper limit for this system but yet is large enough to demonstrate that the system is not restricted to a select few outcomes. Using metrics to gauge the robustness of these phenotypes to parameter perturbations, we identify a select subset of novel phenotypes that are the most promising for experimental validation. In addition, our model calculations provide a layout of these phenotypes in network parameter space. Analyzing this landscape of multicellular phenotypes yielded two significant insights. First, we show that experimentally well-established mutant phenotypes may be rendered using non-canonical network perturbations. Second, we show that the predicted multicellular patterns include not only those observed in C. elegans, but also those occurring exclusively in other species of the Caenorhabditis genus. This result demonstrates that quantitative diversification of a common regulatory network is indeed demonstrably sufficient to generate the phenotypic differences observed across three major species within the Caenorhabditis genus. Using our computational framework, we systematically identify the quantitative changes that may have occurred in the regulatory network during the evolution of these species. Our model predictions show that significant phenotypic diversity may be sampled through quantitative variations in the regulatory network without overhauling the core network architecture. Furthermore, by comparing the predicted landscape of phenotypes to multicellular patterns that have been experimentally observed across multiple species, we systematically trace the quantitative regulatory changes that may have occurred during the evolution of the Caenorhabditis genus

Evaluación de la prevalencia de los genes polimórficos de la enzima convertidora de angiotensina y del angiotensinógeno en hipertensos primarios de la población peruana

Evaluation of the Prevalence on the Polymorphic genes from the Angiotensin Converting Enzyme and from angiotensinogen on Primary Hypertense People on Peruvian Population.We have decided to identify the prevalence in our population about the most important genetic polymorphisms in the cardiovascular diseases such as the I/D polymorphism of the gene at the angiotensin converting enzyme (ACE) and the polymorphism of the gene at the angiotensinogen (AGT), and also his association with primary High Blood Pressure (HBP). This study has also tried to show that the DD genotype of ACE gene is associated with greater levels of serum ACE at HBP.This study of the type: Case - Control, National Multicentric has included 238 patients, males and females, being 118 hypertensives, who come from 48 families that are compared with 120 normotensives.Some samples have been extracted for the DNA, it has been made the polymorphism analysis for the PCR at the ACE and AGT genes, dosage of serum ACE and the biochemical determination of the lipidic profile.Results: The DD prevalence was of (13/118) 11% and the TT prevalence was (78/118) 66%. We have obtained significant differences on the values of serum ACE: DD 44 ± 20 U/1, ID 33 ± 19 UIL, 13 ± 9.8 U/1 (p<0,001), it has not been association from HBP with those genotypes.Conclusion: We must say that in our sample group the prevalence of TT genotype is bigger than the prevalence of DD genotype. There is a higher level of serum ACE at the DD genotype carriers. We haven't fount any association of those genotypes with the primary HBP.Se decidió identificar la prevalencia en nuestra población de los polimorfismos genéticos más importantes en las enfermedades cardiovasculares como son el polimorfismo I/D del gen de Enzima Convertidora de Angiotensina (ECA) y el polimorfismo M235T del gen del Angiotensinógeno (AGT), así como su asociación con la HTA primaria. Este estudio también pretendió demostrar que el genotipo DD del gen ECA, se asocia a mayores niveles de ECA sérico en HTA primaria.Este estudio de tipo Caso-Control, Multicéntrico Nacional incluyó 238 pacientes de ambos sexos, siendo 118 hipertensos, provenientes de 48 familias que se compararon con 120 normotensos.Se extrajeron muestras para ADN, se realizó el análisis del polimorfismo por PCR en los genes ECA y AGT, dosaje de ECA sérico y la determinación bioquímica del perfil lipídico.Los resultados obtenidos mostraron que la prevalencia de DD fue (13/118)11% y de TT (78/118) 66%. Obtuvimos diferencias significativas en los valores del ECA sérico: DD 44 ± 20 U/l, ID 33 ± 19 U/L, 13 ± 9.8 U/l (p<0,00l), no se encontró asociación de HTA con estos genotipos.Como conclusión tenemos que en nuestro grupo muestral la prevalencia del genotipo TT es mayor que la de DD. Existe un mayor nivel de ECA sérico en los portadores del genotipo DD, respecto a los portadores de ID y de II. No encontramos asociación de estos genotipos con la HTA primari

Ellipsometric Study of SiO x Thin Films by Thermal Evaporation

Abstract This paper presents a study of amorphous SiO x thin films by means of Variable Angle Spectroscopic Ellipsometry (VASE) technique. Tauc Lorentz, Lorentz and Cauchy models have been used to obtain physical thickness and complex refractive index (n and k) from experimental data. In order to obtain a wide range to x stoichiometry values, the films were prepared by vacuum thermal evaporation of SiO on glass substrates, under different and controlled deposition conditions

Chromosome studies in Orchidaceae from Argentina

The center of diversity of Argentinean orchids is in the northeast region of the country. Chromosome numbers and karyotype features of 43 species belonging to 28 genera are presented here. Five chromosome records are the first ones at the genus level; these taxa are Aspidogyne kuckzinskii (2n = 42), Eurystyles actinosophila (2n = 56), Skeptrostachys paraguayensis (2n = 46), Stigmatosema polyaden (2n = 40) and Zygostates alleniana (2n = 54). In addition, a chromosome number is presented for the first time for 15 species: Corymborkis flava (2n = 56), Cyclopogon callophyllus (2n = 28), C. oliganthus (2n = 64), Cyrtopodium hatschbachii (2n = 46), C. palmifrons (2n = 46), Galeandra beyrichii (2n = 54), Habenaria bractescens (2n = 44), Oncidium edwallii (2n = 42), O. fimbriatum (2n = 56), O. pubes (2n = 84), O. riograndense (2n = 56), Pelexia ekmanii (2n = 46), P. lindmanii (2n = 46) and Warrea warreana (2n = 48). For Oncidium longicornu (2n = 42), O. divaricatum (2n = 56) and Sarcoglottis fasciculata (2n = 46+1B?, 46+3B?), a new cytotype was found. Chromosome data support phylogenetic relationships proposed by previous cytological, morphologic and molecular analyses, and in all the cases cover some gaps in the South American literature on orchid chromosomes

An affinity matured minibody for PET imaging of prostate stem cell antigen (PSCA)-expressing tumors

PurposeProstate stem cell antigen (PSCA), a cell surface glycoprotein expressed in normal human prostate and bladder, is over-expressed in the majority of localized prostate cancer and most bone metastases. We have previously shown that the hu1G8 minibody, a humanized anti-PSCA antibody fragment (single-chain Fv-C(H)3 dimer, 80 kDa), can localize specifically and image PSCA-expressing xenografts at 21 h post-injection. However, the humanization and antibody fragment reformatting decreased its apparent affinity. Here, we sought to evaluate PET imaging contrast with affinity matured minibodies.MethodsYeast scFv display, involving four rounds of selection, was used to generate the three affinity matured antibody fragments (A2, A11, and C5) that were reformatted into minibodies. These three affinity matured anti-PSCA minibodies were characterized in vitro, and following radiolabeling with (124)I were evaluated in vivo for microPET imaging of PSCA-expressing tumors.ResultsThe A2, A11, and C5 minibody variants all demonstrated improved affinity compared to the parental (P) minibody and were ranked as follows: A2 > A11 > C5 > P. The (124)I-labeled A11 minibody demonstrated higher immunoreactivity than the parental minibody and also achieved the best microPET imaging contrast in two xenograft models, LAPC-9 (prostate cancer) and Capan-1 (pancreatic cancer), when evaluated in vivo.ConclusionOf the affinity variant minibodies tested, the A11 minibody that ranked second in affinity was selected as the best immunoPET tracer to image PSCA-expressing xenografts. This candidate is currently under development for evaluation in a pilot clinical imaging study

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO