497 research outputs found
Las inhumaciones perinatales de el Castejón de Bargota (Navarra)
Se analizan los restos esqueléticos de dos perinatales, procedentes de un
yacimiento de la Edad del Hierro de la cuenca del Ebro. Ambos proceden de la misma
vivienda
Physiological responses of Lupinus luteus to different copper concentrations
Yellow lupin (Lupinus luteus L.) plants were grown in hydroponic solution for 15 d under different copper
concentrations (0.1, 0.5, 1.0, 10, 25 and 50 μM). With increasing Cu concentration total biomass was not affected, leaf
area slightly decreased, while chlorophyll content decreased considerably. Cu content increased significantly both in
roots and in leaves, but the contents of other ions were only slightly affected at the highest Cu concentration (Mn
content decreased both in roots and in leaves, P content decreased only in leaves and Zn content increased in roots).
Superoxide dismutase (SOD) activity increased up to day 7 after copper application. Peroxidase (GPOD) and
polyphenol oxidase (PPO) activities also increased, while catalase (CAT) activity remained constan
Structure-properties correlations in divalent metal phosphonates
Crystalline metal phosphonates may offer acidic sites, structural flexibility and guest molecules (H2O, heterocyclics, etc.) which can act as proton carriers. In addition, some frameworks are also amenable for post‐synthesis modifications in order to enhance desired properties [1,2].
In this work, we present the synthesis and structural characterization of two hydroxyphosphonoacetates hybrids based on magnesium, [Mg5(O3PCHOHCOO)2(HO3PCHOHCOO)2·8H2O] [Mg5(HPAA)2(H1HPAA)2·8H2O], and zinc, [Zn6K(O3PCHOHCOO)4(OH)·6.5H2O] [Zn6K(HPAA)4(OH)·6.5H2O]. Both solids present three-dimensional frameworks and their crystal structures were solved ab initio from X-ray powder diffraction. The proton conductivity of [Zn6K(HPAA)4(OH)·6.5H2O] as well as ammonia derivatives of M(II)(HO3PCHOHCOO)·2H2O [M(II)=Zn, Mg] will be reported and discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. FQM-1656; MAT2013-41836-
Effects of Electroplated Zinc-Nickel Alloy Coatings on the Fatigue Strength of AISI 4340 High-Strength Steel
Computer simulations of hard pear-shaped particles
We report results obtained from Monte Carlo simulations investi-
gating mesophase formation in two model systems of hard pear-shaped
particles. The first model considered is a hard variant of the trun-
cated Stone-Expansion model previously shown to form nematic and
smectic mesophases when embedded within a 12-6 Gay-Berne-like po-
tential [1]. When stripped of its attractive interactions, however, this system is found to lose its liquid crystalline phases. For particles of length to breadth ratio k = 3, glassy behaviour is seen at high pressures, whereas for k = 5 several bi-layer-like domains are seen, with high intradomain order but little interdomain orientational correlation. For the second model, which uses a parametric shape parameter based on the generalised Gay-Berne formalism, results are presented for particles with elongation k = 3; 4 and 5. Here, the systems with k = 3 and 4 fail to display orientationally ordered phases, but that with k = 5 shows isotropic, nematic and, unusually for a hard-particle model, interdigitated smectic A2 phases.</p
Pharmacological Interventions to Ameliorate Neuropathological Symptoms in a Mouse Model of Lafora Disease
14 páginas; 9 figuras.Lafora disease (LD, OMIM 254780) is a rare fatal neurodegenerative disorder that usually occurs during childhood with generalized tonic-clonic seizures, myoclonus, absences, drop attacks or visual seizures. Unfortunately, at present, available treatments are only palliatives and no curative drugs are available yet. The hallmark of the disease is the accumulation of insoluble polyglucosan inclusions, called Lafora bodies (LBs), within the neurons but also in heart, muscle and liver cells. Mouse models lacking functional EPM2A or EPM2B genes (the two major loci related to the disease) recapitulate the Lafora disease phenotype: they accumulate polyglucosan inclusions, show signs of neurodegeneration and have a dysregulation of protein clearance and endoplasmic reticulum stress response. In this study, we have subjected a mouse model of LD (Epm2b-/-) to different pharmacological interventions aimed to alleviate protein clearance and endoplasmic reticulum stress. We have used two chemical chaperones, trehalose and 4-phenylbutyric acid. In addition, we have used metformin, an activator of AMP-activated protein kinase (AMPK), as it has a recognized neuroprotective role in other neurodegenerative diseases. Here, we show that treatment with 4-phenylbutyric acid or metformin decreases the accumulation of Lafora bodies and polyubiquitin protein aggregates in the brain of treated animals. 4-Phenylbutyric acid and metformin also diminish neurodegeneration (measured in terms of neuronal loss and reactive gliosis) and ameliorate neuropsychological tests of Epm2b-/- mice. As these compounds have good safety records and are already approved for clinical uses on different neurological pathologies, we think that the translation of our results to the clinical practice could be straightforward.This work was supported by grants from the Spanish Ministry of Education and Science SAF2011-27442, Fundació La Marato de TV3 (ref. 100130) and an ACCI2012 action from CIBERER. A.B. holds a postdoctoral fellowship from the Program “Junta para la Ampliación de Estudios” (JAE-Doc) co-funded by the European Social Fund (ESF).Peer reviewe
Study of evolution of microbiological properties in sewage sludge-amended soils: A pilot experience
Large amounts of sewage sludge are generated in urban wastewater treatment plants and used as fertilizer in agriculture due to its characteristics. They can contain contaminants such as heavy metals and pathogenic microorganisms. The objective of this research work is to study, in real conditions, the evolution of microbial concentration in agricultural soils fertilized by biologically treated sewage sludge. The sludge (6.25 tons Ha-1 ) was applied in two agricultural soils with different textures and crops. A microbiological (total coliforms, Escherichia coli, Staphylococcus aureus, Enterococcus sp., Pseudomonas sp., Salmonella sp. and total mesophylls) and physical-chemical characterization of the sludge, soils and irrigation water were carried out. The evolution of these parameters during sowing, growth and harvesting of crops was studied. Initially, sewage sludge had a higher concentration of microorganisms than soils. Irrigation water also contained microorganisms, fewer than sewage sludge amendment but not negligible. After amendment, there were no differences in the microbiological evolution in the two types of soil. In general, bacterial concentrations after crop harvest were lower than bacterial concentrations detected before sewage sludge amendment. Consequently, the application of sludge from water treatment processes did not worsen the microbiological quality of agricultural soil in this study at real conditions
Testing Performance of Current Video Codecs in Teleoperated Mobile Robot Applications: a Practical Experience
Mechanical strength of ground WC-Co cemented carbides after coating deposition
Manufacturing of hardmetal tools often involves surface grinding, ion etching and final coating. Each stage throughout the manufacturing chain introduces surface integrity changes which may be critical for defining the final mechanical behavior of the coated tools. Within this context, an experimental test program has been developed to assess the influence of a coating (TiN) deposition on surface integrity and transverse rupture strength of a previously ground fine-grained WC-Co grade substrate. Four different substrate surface finish conditions (prior to ion etching and coating) were evaluated: as sintered (AS), ground (G), polished (P), and ground plus high temperature annealing (GTT). Surface integrity and fracture resistance characterization, complemented with a detailed fractographic analysis, were performed on both uncoated and coated samples. Results show that the surface integrity after grinding has been partly modified during the ion etching and film deposition processes, particularly in terms of a reduced compressive residual stress state at the substrate surface level. Consequently, the grinding induced strength enhancement in hardmetals is reduced for coated specimens. Main reason behind it is the change of nature, location and stress state acting on critical flaw: from processing defects existing at the subsurface (uncoated G specimens) to grinding-induced microcracks located close to the interface between coating and substrate, but within the subsurface of the latter (coated G specimens). This is not the case for AS and P conditions, where flexural strength does not change as a result of ion etching and coating. Finally, fracture resistance increases slightly for GTT specimens after coating process, possibly caused by a beneficial effect of the deposited film on the residual stress state at the surface.Preprin
An approach to the spatial distribution of fishing effort in the Gulf of Cadiz.
The spatial distribution of the fishing effort exerted
by the trawl fleet of Isla Cristina port (Huelva, Spain)
is simulated by means of an application (FAST) for
Geographic Information Systems (ArcView), which
can offer results just with limited input data.
The simulation were carried out with three input
variables: depth, distance from fishing grounds to port
and the fishing laws in force in the area. The results
obtained from two simulations tested match up the
effort distribution detected in the area for both the fleet
as a whole and a given segment of the same.Postprin
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