588 research outputs found
An evaluation of the feasibility of electrostatic separation for physical soil washing
[EN] We present the first application of electrostatic separation for soil washing. Soil samples were collected from the PTE-containing area of La Cruz in Linares, southern Spain. Using a single-phase high-tension roll separator with voltages ranging from 20 kV to 41.5 kV, we achieved yield values between 0.69% and 9%, with high recovery rates for certain elements such as Zn, Cu, and Mo. SEM-EDX analysis revealed three particle types, including a non-conductive fraction composed of feldspar, a middling fraction composed of mica, and a conductive fraction consisting of PTE-bearing slag grains. Attributive analysis showed that 41.5 kV was the optimal voltage for maximizing PTE concentration. Overall, electrostatic separation is a promising approach for treating soils contaminated with PTEs, particularly in dry climate areas impacted by mining activities.S
Morphostructural characterisation of Spanish Alano as a base for its conservation: preliminar results
Using 68 pure exemplars of the Spanish Alano Dog Breed (37 males and 31 females) we have developed a preliminary study of the breed characterisation analysing several morphostructural variables as a base for the definition of racial pattern, considering that a one of the main objectives of the project entitled Planning of the recuperation and conservation of the Spanish Alano canine breed. All the studied zoometric variables reflected bigger values if males than in females, but we could not proved statistically a clear sexual dimorphism in most of the studied variables. Our results coincide with descriptions and data published by other authors with respect to this breed. In general, from this study we conclude that this population is characterised by braquicephalic proportions, and sublongilineous body proportions, all inside a strong and compact morphostructure. It permit us to clasify this breed inside the group of light molosoids caught dogs.Sobre un total de 68 ejemplares de la raza Alano Español (37 machos y 31 hembras) se realiza un estudio de caracterización racial preliminar, analizando diversas variables morfoestructurales, como base para su utilización en la redacción del patrón racial, considerado como uno de los objetivos iniciales prioritarios en el proyecto denominado Planificación de la recuperación y conservación de la raza canina Alano Español. Todas las variables zoométricas estudiadas reflejaron valores mayores en machos que en hembras, aunque no comprobamos estadísticamente un dimorfismo sexual manifiesto en la mayoría de dichas variables. Asimismo nuestros resultados concuerdan con las descripciones y datos aportados por los distintos autores que estudiaron esta raza anteriormente. En líneas generales, de este estudio se puede concluir que la población estudiada se caracteriza por presentar características braquicéfalas, y proporciones corporales sublongilíneas dentro de una morfoestructura general fuerte y compacta, lo que nos permite encuadrar esta raza dentro del grupo de perros molosos ligeros de presa
Combining raw and compositional data to determine the spatial patterns of potentially toxic elements in soils
When considering complex scenarios involving several attributes, such as in environmental characterization, a
clearer picture of reality can be achieved through the dimensional reduction of data.
In this context, maps facilitate the visualization of spatial patterns of contaminant distribution and the identification
of enriched areas. A set, of 15 Potentially Toxic Elements (PTEs) – (As, Ba, Cd, Co, Cr, Cu, Hg,Mo, Ni, Pb, Sb, Se,
Tl, V, and Zn), was measured in soil, collected in Langreo's municipality (80 km2), Spain.
Relative enrichment (RE) is introduced here to refer to the proportion of elements present in a given context. Indeed,
a novel approach is provided for research into PTE fate. This method involves studying the variability of PTE
proportions throughout the study area, thereby allowing the identification of dissemination trends.
Traditional geostatistical approaches commonly use raw data (concentrations) accepting that the elements analyzedmake
up the entirety of the soil. However, in geochemical studies the analyzed elements are just a fraction
of the total soil composition. Therefore, considering compositional data is pivotal. The spatial characterization of
PTEs considering raw and compositional data together allowed a broad discussion about, not only the PTEs
concentration's distribution but also to reckon possible trends of relative enrichment (RE).
Transformations to open closed data are widely used for this purpose. Spatial patterns have an indubitable interest.
In this study, the Centered Log-ratio transformation (clr) was used, followed by its back-transformation, to
build a set of compositional data that, combined with raw data, allowed to establish the sources of the PTEs
and trends of spatial dissemination.info:eu-repo/semantics/publishedVersio
Quons Restricted to the Antisymmetric Subspace: Formalism and Applications
In this work we develop a formalism to treat quons restricted to the
antisymmetric part of their many-body space. A model in which a system of
identical quons interact through a pairing force is then solved within this
restriction and the differences between our solution and the usual fermionic
model solution are then presented and discussed in detail. Possible connections
to physical systems are also considered.Comment: 12 pages, 3 figure
Modification of the epigenome in human cancer cells by expression of a DNA demethylase from plants
Model-based mechanical and control design of a three-axis platform
In recent times, the interest from scientific and industrial community for the micrometric range has observed an important growth. The advances in microelectronics or the research on microbiology are just two examples of fields requiring technologies capable of assuring accurate displacements in that range. The present work focuses on the mechanical and control design of a micrometer range positioning and tracking platform using mathematical models. In a first phase, these models permit to identify the relationship between the dynamic performance of the structure and the mechanical properties of the elements that compose it. At the very beginning of the design, this information is used for the development of the different parts of the platform. Afterwards, once an initial design is finished and 3D models are available, the design is refined using finite element tools. In parallel to the mechanical design, the knowledge of the system embodied in the mathematical model is profited in the design of a control strategy for tracking and positioning. The proposed control strategy combines a linear controller based on differential flatness with a hysteresis compensator for correcting this nonlinear effect of the piezoelectric actuators. In the present paper, the mathematical derivation of the system model, its application to the design and validation of the platform and the final closed loop experimental evaluation are described
Special Geometry of Euclidean Supersymmetry I: Vector Multiplets
We construct the general action for Abelian vector multiplets in rigid
4-dimensional Euclidean (instead of Minkowskian) N=2 supersymmetry, i.e., over
space-times with a positive definite instead of a Lorentzian metric. The target
manifolds for the scalar fields turn out to be para-complex manifolds endowed
with a particular kind of special geometry, which we call affine special
para-Kahler geometry. We give a precise definition and develop the mathematical
theory of such manifolds. The relation to the affine special Kahler manifolds
appearing in Minkowskian N=2 supersymmetry is discussed. Starting from the
general 5-dimensional vector multiplet action we consider dimensional reduction
over time and space in parallel, providing a dictionary between the resulting
Euclidean and Minkowskian theories. Then we reanalyze supersymmetry in four
dimensions and find that any (para-)holomorphic prepotential defines a
supersymmetric Lagrangian, provided that we add a specific four-fermion term,
which cannot be obtained by dimensional reduction. We show that the Euclidean
action and supersymmetry transformations, when written in terms of
para-holomorphic coordinates, take exactly the same form as their Minkowskian
counterparts. The appearance of a para-complex and complex structure in the
Euclidean and Minkowskian theory, respectively, is traced back to properties of
the underlying R-symmetry groups. Finally, we indicate how our work will be
extended to other types of multiplets and to supergravity in the future and
explain the relevance of this project for the study of instantons, solitons and
cosmological solutions in supergravity and M-theory.Comment: 74 page
Granzyme A inhibition reduces inflammation and increases survival during abdominal sepsis
Aims: Peritonitis is one of the most common causes of sepsis, a serious syndrome characterized by a dysregulated systemic inflammatory response. Recent evidence suggests that Granzyme A (GzmA), a serine protease mainly expressed by NK and T cells, could act as a proinflammatory mediator and could play an important role in the pathogenesis of sepsis. This work aims to analyze the role and the therapeutic potential of GzmA in the pathogenesis of peritoneal sepsis. Methods: The level of extracellular GzmA as well as GzmA activity were analyzed in serum from healthy volunteers and patients with confirmed peritonitis and were correlated with the Sequential Organ Failure Assessment (SOFA) score. Peritonitis was induced in C57Bl/6 (WT) and GzmA-/- mice by cecal ligation and puncture (CLP). Mice were treated intraperitoneally with antibiotics alone or in combination serpinb6b, a specific GzmA inhibitor, for 5 days. Mouse survival was monitored during 14 days, levels of some proinflammatory cytokines were measured in serum and bacterial load and diversity was analyzed in blood and spleen at different times. Results: Clinically, elevated GzmA was observed in serum from patients with abdominal sepsis suggesting that GzmA plays an important role in this pathology. In the CLP model GzmA deficient mice, or WT mice treated with an extracellular GzmA inhibitor, showed increased survival, which correlated with a reduction in proinflammatory markers in both serum and peritoneal lavage fluid. GzmA deficiency did not influence bacterial load in blood and spleen and GzmA did not affect bacterial replication in macrophages in vitro, indicating that GzmA has no role in bacterial control. Analysis of GzmA in lymphoid cells following CLP showed that it was mainly expressed by NK cells. Mechanistically, we found that extracellular active GzmA acts as a proinflammatory mediator in macrophages by inducing the TLR4-dependent expression of IL-6 and TNFa. Conclusions: Our findings implicate GzmA as a key regulator of the inflammatory response during abdominal sepsis and provide solid evidences about its therapeutic potential for the treatment of this severe pathology
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