875 research outputs found
Hexaaquazinc(II) dinitrate bis[5-(pyridinium-3-yl)tetrazol-1-ide]
Indexación: Scopus.Funding for this research was provided by: Fondecyt Regular (award No. 1151527); Proyecto REDES ETAPA INICIAL, Convocatoria 2017 (award No. REDI170423); Millennium Institute for Research in Optics (MIRO); Basal USA (award No. 1799).Hexaaquazinc(II) dinitrate 5-(pyridinium-3-yl)tetrazol-1-ide, [Zn(H2 O)6](NO 3)2 ·2C6H5 N 5, crystallizes in the space group P. The asymmetric unit contains one zwitterionic 5-(pyridinium-3-yl)tetrazol-1-ide molecule, one NO3-anion and one half of a [Zn(H2 O)6]2+ cation (symmetry). The pyridinium and tetrazolide rings in the zwitterion are nearly coplanar, with a dihedral angle of 5.4 (2)°. Several O-H..N and N-H..O hydrogen-bonding interactions exist between the [Zn(H2 O)6]2+ cation and the N atoms of the tetrazolide ring, and between the nitrate anions and the N-H groups of the pyridinium ring, respectively, giving rise to a three-dimensional network. The 5-(pyridinium-3-yl)tetrazol-1-ide molecules show parallel-displaced π-π stacking interactions; the centroid-centroid distance between adjacent tetrazolide rings is 3.6298 (6) Å and that between the pyridinium and tetrazolide rings is 3.6120 (5) Å. © 2018 Chi-Duran et al.http://journals.iucr.org/e/issues/2018/09/00/cq2025/index.htm
Mocarts: a lightweight radiation transport simulator for easy handling of complex sensing geometries
In functional neuroimaging (fNIRS), elaborated sensing geometries pairing multiple light sources and detectors arranged over the tissue surface are needed. A variety of software tools for probing forward models of radiation transport in tissue exist, but their handling of sensing geometries and specification of complex tissue architectures is, most times, cumbersome. In this work, we introduce a lightweight simulator, Monte Carlo Radiation Transport Simulator (MOCARTS) that attends these demands for simplifying specification of tissue architectures and complex sensing geometries. An object-oriented architecture facilitates such goal. The simulator core is evolved from the Monte Carlo Multi-Layer (mcml) tool but extended to support multi-channel simulations. Verification against mcml yields negligible error (RMSE~4-10e-9) over a photon trajectory. Full simulations show concurrent validity of the proposed tool. Finally, the ability of the new software to simulate multi-channel sensing geometries and to define biological tissue models in an intuitive nested-hierarchy way are exemplified
Población anidante e impacto en la pesca artesanal del cormorán neotropical Phalacrocorax brasilianus Suliformes:Phalacrocoracidae), en el sitio Ramsar Cerrón Grande, El Salvador.
The neotropical cormorant (Phalacrocorax brasilianus) is a species of waterfowl abundant in the wetlands of El Salvador. Fish predation on aquatic ecosystems is generating a conflict with fishermen that associating declining fishing with predatory behavior of this bird. From April 2010 to February 2011, an investigation was conducted aimed at knowing the state of the population of P. brasilianus in the Ramsar wetland Cerron Grande, El Salvador. The study was conducted through counting and collecting of birds, to analyze the stomachic contents. The maximum recorded was 28.063 individuals and 3,000 breeding pairs. 266 birds were collected, on 207 it found fish in their stomachs, whose individual weight ranged from 2-307 g ± 52 g. A total of 1,078 fish specimens was found, from ten species, four of them obtained the highest values of abundance: bagre (Cathorops steindachneri) with 29%, followed by guapote (Parachromis managuensis) with 25%, tilapia (Oreochromis niloticus) with 22% and plateada (Astyanax aeneus, Roeboides bouchellei) with 31%
The Inverse Scattering Method, Lie-Backlund Transformations and Solitons for Low-energy Effective Field Equations of 5D String Theory
In the framework of the 5D low-energy effective field theory of the heterotic
string with no vector fields excited, we combine two non-linear methods in
order to construct a solitonic field configuration. We first apply the inverse
scattering method on a trivial vacuum solution and obtain an stationary
axisymmetric two-soliton configuration consisting of a massless gravitational
field coupled to a non-trivial chargeless dilaton and to an axion field endowed
with charge. The implementation of this method was done following a scheme
previously proposed by Yurova. We also show that within this scheme, is not
possible to get massive gravitational solitons at all. We then apply a
non-linear Lie-Backlund matrix transformation of Ehlers type on this massless
solution and get a massive rotating axisymmetric gravitational soliton coupled
to axion and dilaton fields endowed with charges. We study as well some
physical properties of the constructed massless and massive solitons and
discuss on the effect of the generalized solution generating technique on the
seed solution and its further generalizations.Comment: 17 pages in latex, changed title, improved text, added reference
Gamma Ray Bursts: Observations and Theoretical Conjectures
Gamma Ray Bursts (GRBs) are short bursts of very high energy photons which were discovered in the late 1960s. Ever since their discovery, scientists have wondered about their origin. Nowadays it is known that they originate outside the Milky Way because of their high red shift rst measured in the afterglows thanks to the Beppo-SAX satellite and ground-based observations. However, theoreticians still do not agree about the mechanism that generates the bursts, and different competing models are animatedly debated. Current GRB experiments include the Swift satellite and the Pierre Auger Observatory that could detect GRBs with an increase of the background. A forthcoming dedicated experiment is GLAST, a satellite observatory for detecting gamma rays with energies up to 300 GeV, whose launch is scheduled for early 2008
Unsupervised method to classify PM10 pollutant concentrations
In this paper a method based mainly on Data Fusion and Artificial Neural Networks to classify one of the most important pollutants such as Particulate Matter less than 10 micrometer in diameter (PM10) concentrations is proposed. The main objective is to classify in two pollution levels (Non-Contingency and Contingency) the pollutant concentration. Pollutant concentrations and meteorological variables have been considered in order to build a Representative Vector (RV) of pollution. RV is used to train an Artificial Neural Network in order to classify pollutant events determined by meteorological variables. In the experiments, real time series gathered from the Automatic Environmental Monitoring Network (AEMN) in Salamanca Guanajuato Mexico have been used. The method can help to establish a better air quality monitoring methodology that is essential for assessing the effectiveness of imposed pollution controls, strategies, and facilitate the pollutants reduction
A space for the living and the dead: The Chalcolithic ditched enclosured settlement of Camino de las Yeseras (San Fernando de Henares, Madrid)
Se presentan los resultados preliminares de la excavación de un gran poblado de fosos calcolítico, cuya situación
estratégica ayudó a ser un centro de producción e intercambio de excedentes en materias primas (sílex,
granito y piedras metamórficas) y productos agropecuarios e industriales por otros foráneos (cobre, variscita,
cinabrio, marfil y oro). Los rituales funerarios son de una gran variedad, individuales y colectivos, en covachas
e hipogeos, con o sin ajuar campaniforme, algunos de los últimos con ricos ajuares áureos y ebúrneos. Los
datos óseos de algunos inhumados campaniformes apuntan a un aspecto físico muy llamativo en vida, mientras
los depósitos con fauna, en composición taxonómica variada, indican una compleja relación simbólica con el
mundo animal. El yacimiento resulta clave para un mejor conocimiento del período calcolítico y el impacto
campaniforme y sus rituales funerarios en la consolidación y diferenciación de las primeras sociedades metalúrgicas
del interior peninsularThe preliminary results are presented of the excavations in a large, ditched enclosured Chalcolithic settlement.
The site was probably a central place in the production and long-distance exchange of surplus. The accumulations
found of raw materials (flint, granite and metamorphic stones) and agricultural, stockbreeding and industrial
products were exchanged by other foreign products (variscite, cinnabar, ivory and gold). Ritual data are
also remarkable: a significant number of individual and collective burials have been recorded in pits, small artificial
caves and hypogeos, delimited in special areas. The richer burials had Ciempozuelos-style Bell-beaker
elements and prestige items, such as gold and ivory beads. Osteomorphic and size features of some Bell-beaker
individuals point out a remarkable physical aspect during their life time. The faunal deposits, which included
mixed species associations, evidence a complex symbolic relationship with animals. The site is essential for the
knowledge of the Chalcolithic period and the impact of Bell-beaker customs and funerary rituals in the consolidation
of social inequalities amidst the first metallurgical societies of the interior of the Iberian Peninsul
Training Reading Skills in Central Field Loss Patients: Impact of Clinical Advances and New Technologies to Improve Reading Ability
The primary goal of patients with central field loss attending to visual rehabilitation (VR) offices is to get adapted to daily life activities in near vision, mainly looking for recovering their ability to read again. The disparity in the functionality of these patients, due to the new advances in medical treatment and the increasing number of new apps and technological devices in the market, implies a heterogeneity in the reading training programs to be applied, and consequently a variability in the results obtained. Currently, with the increasing access to information and communication technologies and social networks, the opportunities for improving their access to information and communication is taken an important role. For this reason, the basis of ad-hoc evidence-based reading training programs is needed to standardized the clinical practice in reading rehabilitation for visual impaired and blind patients. This chapter will go in depth into these topics offering an exhaustive state of the art of reading rehabilitation for central field loss patients that will be useful for clinicians dedicated to the rehabilitation of visual impaired and blind people
Escuela y comunidad: Una experiencia de desarrollo comunitario
Nuestra comunicación presenta la experiencia que se está desarrollando en dos barrios periféricos con la participación de cuatro centros educativos: dos de educación Infantil y Primaria (CEIP) y dos Institutos de Educación Secundaria (IES). Partiendo de la cultura como manifestación social, reflexionamos sobre la cultura escolar y su relación con el fracaso escolar, y analizamos las posibilidades del desarrollo comunitario como vía para afrontarlo. En esta experiencia, el proceso de desarrollo comunitario está en su fase inicial y se ha consolidado la coordinación de los diferentes servicios y recursos públicos y privados que inciden en la zona. El trabajo de prevención y promoción que se está realizando en las calles gracias al proceso “El Patio”, se complementa con la participación de los centros educativos, además del uso comunitario de sus instalaciones. Actualmente estamos realizando un diagnóstico comunitario en el que hemos finalizado la recopilación de datos objetivos y estadísticos así como el proceso de audición para la parte subjetiva. Con la síntesis de estos datos se iniciará un proceso de discusión con toda la población para la búsqueda comunitaria de alternativas
Influence of pore size in protein G'-grafted mesoporous silica nanoparticles as a serum pretreatment system for in vitro allergy diagnosis
Particles with the capacity to bind to immunoglobulin G (IgG) can be used for the purification of IgG or to process clinical samples for diagnostic purposes. For in vitro allergy diagnosis, the high IgG levels in serum can interfere with the detection of allergen-specific IgE, the main diagnostic biomarker. Although commercially available, current materials present a low IgG capture capacity at large IgG concentrations or require complex protocols, preventing their use in the clinic. In this work, mesoporous silica nanoparticles are prepared with different pore sizes, to which IgG-binding protein G’ is grafted. It is found that for one particular optimal pore size, the IgG capture capacity of the material is greatly enhanced. The capacity of this material to efficiently capture human IgG in a selective way (compared to IgE) is demonstrated in both solutions of known IgG concentrations as well as in complex samples, like serum, from healthy controls and allergic patients using a simple and fast incubation protocol. Interestingly, IgG removal using the best-performing material enhances in vitro IgE detection in sera from patients allergic to amoxicillin. These results highlight the great translation potential of this strategy to the clinic in the context of in vitro allergy diagnosis.Funding for Open Access charge: Universidad de Málaga/CBUA. TEM experiments
were performed in the ICTS “NANBIOSIS,” more specifically in the U28
Unit at IBIMA Plataforma BIONAND
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