Laser pointer maculopathy. A new public health problem?

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Effects of Topography and Surface Soil Cover on Erosion for Mining Reclamation: The Experimental Spoil Heap at El Machorro Mine (Central Spain)

Mining reclamation tries to reduce environmental impacts, including accelerated runoff, erosion and sediment load in the nearby fluvial networks and their ecosystems. This study compares the effects of topography and surface soil cover on erosion on man-made slopes coming from surface mining reclamation in Central Spain. Two topographic profiles, linear and concave, with two surface soil covers, subsoil and topsoil, were monitored for two hydrologic years. Sediment load, rill development and plant colonization from the four profiles were measured under field conditions. The results show that, in the case of this experiment, a thick and non-compacted topsoil cover on a linear slope yielded less sediment than carbonate colluvium or topsoil cover on a concave slope. This study also shows that vegetation establishment, which plays an important role in erosion control, depends on topography. Plant cover was more widespread and more homogeneous on linear profiles with topsoil cover. On concave slopes, plant establishment was severely limited on the steepest upper part and favoured in the bottom. This study suggests that management of topography and surface soil cover should be approached systematically, taking three outcomes into consideration: (i) topsoil can lead to a successful mining reclamation regardless of topography, (ii) created concave slopes can lead to a successful mining reclamation and (iii) topography determines the vegetation colonization pattern.The experiment was funded by a research contract between the Spanish mining company 602 CAOBAR S.A. and the Department of Geodynamics of the Complutense University of Madrid 603 (research contract numbers 234/2007, 290/2008 261/2009). The data analyses and manuscript 604 production were developed within two Research Projects, CGL2009-14508-C02-01 and 605 CGL2010-21754-C02, of the Spanish Ministry of Science and Technology and by the 606 Ecological Restoration network REMEDINAL-2 (S2009/AMB-1783).Peer reviewe

Structure and genetic relationships between serrana de Teruel breed and other cattle breeds reared in Spain

In this work we analyze by microsatellite markers the genetic diversity, structure and relationships of the indigenous endangered Serrana de Teruel cattle breed with different breeds reared in Spain. All loci were polymorphic and a total of 198 alleles were observed across loci, with a mean of 6.79. Observed and expected heterozygosities values shown the high variability of Serrana de Teruel breed with values of 0.67 and 0.68 respectively. The neighbour net based on Reynolds distances shown the close genetic relationship among Serrana de Teruel and the mountain Parda de Montaña and Pirenaica breeds. STRUCTURE results showed a 47.5% of correctly assigned individuals to Serrana de Teruel breed using a q>0.8 threshold. The admixed animals shown a clear influence of Parda de Montaña breed.En este trabajo se analiza la variabilidad genética de la raza autóctona en peligro de extinción Serrana de Teruel, así como su relación con las ra-zas bovinas explotadas en España: Albera, Pajuna, Avileña-Negra Ibérica, Serrana Negra, Pirenaica y Parda de Montaña. La caracterización genética se ha realizado mediante marcadores microsatélites, todos han resultado polimórficos detectándose un total de 198 alelos con una media de 6,79 alelos por locus. Las heterocigosidades observadas y esperadas fueron altas y similares en el equilibrio, con valores de 0,67 y 0,68 respectivamente. A partir del estudio de las relaciones filogenéticas se ha podido observar la cercanía de la raza Serrana de Teruel con las razas de montaña Pirenaica y Parda de Montaña. Mediante el estudio de la estructura genética se observó que el porcentaje de animales correctamente asignados a la Serrana de Teruel para q>0,8 fue del 47,5%, apreciándose una clara influencia de la raza Parda de Montaña en los individuos mezclados

Síndrome de Mazabraud: Presentación de un caso clínico y revisión de la literatura

El síndrome de Mazabraud se define como la asociación de una tumoración de partes blandas, el mixoma intramuscular, y un tumor óseo, la displasia fibrosa. Se realiza una revisión bibliográfica de los casos publicados en la literatura, desde que en 1957, Mazabraud acuñó esta asociación como síndrome. El caso clínico corresponde a un varón de 43 años de edad con antecedentes de nódulo frío tiroideo, pigmentación cutánea y lesiones óseas en pelvis y tercio proximal fémur derecho, que acudió a la consulta por presentar una tumoración de partes blandas a nivel del muslo derecho de unos meses de evolución. Tras realizar biopsia de la misma se diagnosticó de mixoma intramuscular. El paciente se intervino quirúrgicamente practicándose resección amplia de la lesión. Hasta la fecha el enfermo no ha presentado recidiva de la lesión de partes blandas, y la displasia ósea no ha sufrido transformación maligna.Mazabraud's síndrome is the association of a soft-tissue tumour, intramuscular myxonma and a bone tumour, fibrous dysplasia. We review the literature since Mazabraud, in 1957 described this syndrome. We report a 43 years male who consulted for a soft-time mass in the right thigh. He also had bone lesions in pelvis and right femur that were diagnosted of fibrous dysplasia. We made a biopsy of soft-tissue tumour and it was diagnosed of intramuscular myxom. The patient was operated and the mass was removed. Till now, there is no recurrence of the myxom and there is no malignant degeneration of the fibrous dysplasia

Experimental and numerical study of wind flow behind windbreaks

The shelter effect of a windbreak protects aggregate piles and provides a reduction of particle emissions in harbours. RANS (Reynolds-averaged Navier–Stokes equations) simulations using three variants of k–ε (standard k–ε, RNG k–ε and realizable k–ε) turbulence closure models have been performed to analyse wind flow characteristics behind an isolated fence located on a flat surface without roughness elements. The performance of the three turbulence models has been assessed by wind tunnel experiments. Cases of fences with different porosities (φ) have been evaluated using wind tunnel experiments as well as numerical simulations. The aim is to determine an optimum porosity for sheltering effect of an isolated windbreak. A value of 0.35 was found as the optimum value among the studied porosities (φ=0, 0.1, 0.24, 0.35, 0.4, 0.5)

Characterization of goat colostrum oligosaccharides by nano-liquid chromatography on chip quadrupole time-of-flight mass spectrometry and hydrophilic interaction liquid chromatography-quadrupole mass spectrometry

A detailed qualitative and quantitative characterization of goat colostrum oligosaccharides (GCO) has been carried out for the first time. Defatted and deproteinized colostrum samples, previously treated by size exclusion chromatography (SEC) to remove lactose, were analyzed by nanoflow liquid chromatography–quadrupole-time of flight mass spectrometry (Nano-LC-Chip–Q-TOF MS). Up to 78 oligosaccharides containing hexose, hexosamine, fucose, N-acetylneuraminic acid or Nglycolylneuraminic acid monomeric units were identified in the samples, some of them detected for the first time in goat colostra. As a second step, a hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC-MS) methodology was developed for the separation and quantitation of the main GCO, both acidic and neutral carbohydrates. Among other experimental chromatographic conditions, mobile phase additives and column temperature were evaluated in terms of retention time, resolution, peak width and symmetry of target carbohydrates. Narrow peaks (wh: 0.2–0.6 min) and good symmetry (As: 0.8–1.4) were obtained for GCO using an acetonitrile:water gradient with 0.1% ammonium hydroxide at 40 ◦C. These conditions were selected to quantify the main oligosaccharides in goat colostrum samples. Values ranging from 140 to 315 mg L−1 for neutral oligosaccharides and from 83 to 251 mg L−1 for acidic oligosaccharides were found. The combination of both techniques resulted to be useful to achieve a comprehensive characterization of GCO.This work has been funded by Junta de Andalucía (project AGR2011-7626), CSIC (project i-link0827), Comunidad Autónoma de Madrid (Spain) and European funding from FEDER program (AVANSECAL-CM S2013/ABI-3028) and Fundación Ramón Areces. This work was also supported by the UC Davis RISE program and the National Institutes of Health awards R21AT006180, R01AT007079, R01AT008759-02.Peer reviewe

Mycobacterial aminoglycoside acetyltransferases: a little of drug resistance, and a lot of other roles

Aminoglycoside acetyltransferases are important determinants of resistance to aminoglycoside antibiotics in most bacterial genera. In mycobacteria, however, aminoglycoside acetyltransferases contribute only partially to aminoglycoside susceptibility since they are related with low level resistance to these antibiotics (while high level aminoglycoside resistance is due to mutations in the ribosome). Instead, aminoglycoside acetyltransferases contribute to other bacterial functions, and this can explain its widespread presence along species of genus Mycobacterium. This review is focused on two mycobacterial aminoglycoside acetyltransferase enzymes. First, the aminoglycoside 2'-N-acetyltransferase [AAC(2')], which was identified as a determinant of weak aminoglycoside resistance in M. fortuitum, and later found to be widespread in most mycobacterial species; AAC(2') enzymes have been associated with resistance to cell wall degradative enzymes, and bactericidal mode of action of aminoglycosides. Second, the Eis aminoglycoside acetyltransferase, which was identified originally as a virulence determinant in M. tuberculosis (enhanced intracellular survival); Eis protein in fact controls production of pro-inflammatory cytokines and other pathways. The relation of Eis with aminoglycoside susceptibility was found after the years, and reaches clinical significance only in M. tuberculosis isolates resistant to the second-line drug kanamycin. Given the role of AAC(2') and Eis proteins in mycobacterial biology, inhibitory molecules have been identified, more abundantly in case of Eis. In conclusion, AAC(2') and Eis have evolved from a marginal role as potential drug resistance mechanisms into a promising future as drug targets

Strongly hyperbolic Hamiltonian systems in numerical relativity: Formulation and symplectic integration

We consider two strongly hyperbolic Hamiltonian formulations of general relativity and their numerical integration with a free and a partially constrained symplectic integrator. In those formulations we use hyperbolic drivers for the shift and in one case also for the densitized lapse. A system where the densitized lapse is an external field allows to enforce the momentum constraints in a holonomically constrained Hamiltonian system and to turn the Hamilton constraint function from a weak to a strong invariant. These schemes are tested in a perturbed Minkowski and the Schwarzschild space-time. In those examples we find advantages of the strongly hyperbolic formulations over the ADM system presented in [arXiv:0807.0734]. Furthermore we observe stabilizing effects of the partially constrained evolution in Schwarzschild space-time as long as the momentum constraints are enforced.Comment: This version clarifies some points concerning the interpretation of the result

Electron angular distributions in dissociative photoionization of the hydrogen molecule.

Se propone un método para calcular distribuciones angulares de electrones ionizados en la molécula de hidrógeno fija en el espacio sometida a pulsos láser intensos y ultracortos, basado en la solución desde primeros principios de la ecuación de Schrödinger dependiente del tiempo. Esta solución nos permite tener una visión temporal de la interferencias generadas en el canal de ionización disociativa (en el espectro de energía cinética de los protones) debido a la presencia de la autoionización de estados doblemente excitados de la molécula de hidrógeno. Se muestra específicamente cómo la autoionización durante el proceso de fotoionización disociativa también puede inducir una asimetría en la distribución angular del electrón ionizado con respecto a la inversión nuclear, un efecto no intuitivo a pesar de estar tratando con un sistema homonuclear