Liquid culture for isolating microorganisms with potential to degrade methyl parathion from agricultural soils and organic waste.

The search for microorganisms with high capacity for pesticide degradation is a very interesting attempt to approach bioremediation strategies in order to prevent contamination. This study evaluates the potential of agricultural soils and solid organic waste cultures microbial isolation as a strategy for screening microorganisms with potential for Methyl parathion (MP) degradation. For the study, microbial consortia were recovered from the liquid fraction of suspension cultures of agricultural soils and solid organic waste. Then, the MP degradation ability and its toxic effect on microbial activity were determined during microbial incubations under laboratory controlled conditions. The results showed that it is not possible to recover the active microorganisms that have potential to degrade the MP from the agricultural soils. However, an active consortium that would degrade both MP and its degradation products was isolated from the organic solid waste

Liquid culture for isolating microorganisms with potential to degrade methyl parathion from agricultural soils and organic waste.

The search for microorganisms with high capacity for pesticide degradation is a very interesting attempt to approach bioremediation strategies in order to prevent contamination. This study evaluates the potential of agricultural soils and solid organic waste cultures microbial isolation as a strategy for screening microorganisms with potential for Methyl parathion (MP) degradation. For the study, microbial consortia were recovered from the liquid fraction of suspension cultures of agricultural soils and solid organic waste. Then, the MP degradation ability and its toxic effect on microbial activity were determined during microbial incubations under laboratory controlled conditions. The results showed that it is not possible to recover the active microorganisms that have potential to degrade the MP from the agricultural soils. However, an active consortium that would degrade both MP and its degradation products was isolated from the organic solid waste

Vertical variation of atrazine mineralization capacity in soils

Se estudió la variación de la capacidad de mineralización de atrazina en dos suelos de la provincia de Córdoba, Argentina. Se seleccionaron dos perfiles de suelos con (suelo adaptado) y sin (suelo no adaptado) historia de aplicación de atrazina. La evolución de atrazina fue caracterizada mediante el balance de la radioactividad del 14C del anillo triazínico identificando las fracciones mineralizada,extractable y no extractable, durante incubaciones en condiciones de laboratorio con suelo tratado con calor (T105) y sin él (Control). La disminución de la capacidad de degradación de atrazina después de la inactivación microbiana y la limitada recuperación de esa capacidad observada en el perfil de suelo adaptado sugirió que los microorganismos degradadores de atrazina estarían distribuidos en todo el perfil siendo los responsables de la mineralización de atrazina en los horizontes subsuperficiales. Contrariamente, en el perfil de suelo no adaptado,la recuperación de la mineralización de atrazina a niveles similares o ligeramente superiores a los del Control corroboró la vía cometabólica del proceso característica de suelos sin historia de uso de atrazina. La capacidad de mineralizaciónde atrazina por los horizontes subsuperficiales, donde tiende a acumularse este herbicida, en suelos con aplicaciones frecuentes de atrazina debiera ser considerada y estimulada como un mecanismo de bioremediación natural

Bioerosion and palaeoecological association of osteophagous insects in the Maastrichtian dinosaur Arenysaurus ardevoli

Bioerosions produced by the osteophagous diet of animals that fed on dinosaur bones are very scarce in the European fossil record. Herein we present bioerosion on hadrosaurid remains from the Maastrichtian Tremp Formation of the Pyrenean Basin, which is only the second such case recorded from the Iberian-Occitan Plate besides a sauropod from the Jurassic-Cretaceous of Valencia. The hadrosaurid fossil record is particularly rich in the Blasi sites of the Tremp Formation located in the municipality of Arén (Huesca, Spain). In this article, bones referred to the hadrosaurid Arenysaurus ardevoli from the Blasi-3 site are analysed to shed light on the palaeoenvironment and on the presence of a palaeoecological interaction between the hadrosaurid carcase and osteophagous tracemakers. Bioerosions recorded on the bones comprise tunnels, roundish holes, and straight notches, similar to the traces attributed to necrophagous insects (cf. Cuniculichnus seilacheri). Here, we record the first instance of the activity of these animals on dinosaur bones in the Upper Cretaceous of the Ibero-Occitan Plate. The results presented lead us to infer that the Arenysaurus bones were possibly transported by a storm or similar event to the Blasi-3 site, where they were exposed to post-mortem biotic interactions (eaten and partially decomposed by dermestid beetles) for a prolonged time period before they were completely buried. © 2021 The Authors. Lethaia published by John Wiley & Sons Ltd on behalf of Lethaia Foundatio

Optimizing omnidirectional reflection by multilayer mirrors

Periodic layered media can reflect strongly for all incident angles and polarizations in a given frequency range. Quarter-wave stacks at normal incidence are commonplace in the design of such omnidirectional reflectors. We discuss alternative design criteria to optimize these systems.Comment: 9 pages, 6 figures. To be published in J. Opt. A: Pure and Applied Optic

Genética de las poblaciones ibéricas de trufa negra (Tuber melanosporum)

La trufa negra tiene una gran importancia económica y social. En el presente artículo de divulgación científica se muestran, de manera sencilla y breve, los resultados obtenidos en el primer estudio genético conducido sobre poblaciones ibéricas silvestres de Tuber melanosporum. Se ha detectado una elevada diversidad genética, que muestra el buen estado de conservación genética, así como una alta estructura genética entre poblaciones y una clara diferenciación entre los núcleos geográficos del noreste y sureste de la península ibérica, motivadas por la presencia del Sistema Ibérico, que puede estar actuando como barrera genética. Por otra parte, los resultados permiten pensar que la mayoría de las poblaciones meridionales, y algunas del centro y norte, sobrevivieron a las glaciaciones. Este artículo constituye la base de trabajos sobre expresión diferencial de aromas, conservación de la especie y desarrollo de marcas de calidad ligadas a este producto

Direct epitaxial growth of polar Hf0.5 Zr0.5 O2 films on corundum

Single-phase epitaxial Hf0.5 Zr0.5 O2 films with non-centrosymmetric orthorhombic structure have been grown directly on electrode-free corundum (a-Al2 O3) substrates by pulsed laser deposition. A combination of high-resolution X-ray diffraction and X-ray absorption spectroscopy confirms the epitaxial growth of high-quality films belonging to the Pca21 space group, with 111] out-of-plane orientation. The surface of a 7-nm-thick sample exhibits an atomic step-terrace structure with a corrugation of the order of one atomic layer, as proved by atomic force microscopy. Scanning transmission electron microscopy reveals that it consists of grains with around 10 nm lateral size. The polar nature of this film has been corroborated by pyroelectric measurements. These results shed light on the mechanisms of the epitaxial stabilization of the ferroelectric phase of hafnia. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Ga+, In+ and Tl+ Impurities in Alkali Halide Crystals: Distortion Trends

A computational study of the doping of alkali halide crystals (AX: A = Na, K; X = Cl, Br) by ns2 cations (Ga+, In+ and Tl+) is presented. Active clusters of increasing size (from 33 to 177 ions) are considered in order to deal with the large scale distortions induced by the substitutional impurities. Those clusters are embedded in accurate quantum environments representing the surrounding crystalline lattice. The convergence of the distortion results with the size of the active cluster is analyced for some selected impurity systems. The most important conclusion from this study is that distortions along the (100) and (110) crystallographic directions are not independent. Once a reliable cluster model is found, distortion trends as a function of impurity, alkali cation and halide anion are identified and discussed. These trends may be useful when analycing other cation impurities in similar host lattices.Comment: LaTeX file. 7 pages and 2 pictures. Accepted for publication in J. Chem. Phy

X-ray microtomographic characterization of highly rough titanium cold gas sprayed coating for identification of effective surfaces for osseointegration

A highly rough titanium coating obtained by Cold Gas Spray (CGS) has been characterized by means of high-resolution 3D microtomography (micro-CT) with the aim to evaluate its open and close porosity for possible use in orthopaedic implants to promote osseointegration. Micro-CT allowed a qualitative and quantitative description of the main features, morphology of the pores and surface roughness of the coating. Several numerical values were obtained to describe size, form and distribution of the closed/inner and open/outer pores. Additionally, surface roughness and open porosity were image-analyzed to find the effective surface for osseointegration

Soil surface structure stabilization by municipal waste compost application

ABSTRACT tional farmyard manure which is no longer available in intensive cropping areas. Loess-derived soils of the northern Paris basin are prone to surface Beneficial effects of sewage sludge application have structure degradation leading to erosion, flooding, and pollution. and soil material were seldom suggested, but a close from the top of surface aggregates to illuviate a few millimeters deeper