Bioprospecting and characterization of poly-bhydroxyalkanoate (PHAs) producing bacteria isolated from Colombian sugarcane producing areas

Bioprospecting for poly-b-hydroxyalkanoate (PHA)-accumulating micro-organisms was carried out in sugarcane growing areas of Colombia. They were isolated in unbalanced culture medium (highcarbon/nitrogen ratio) with sucrose, fructose and glucose used as carbon source. PHAs producing bacteria were identified by staining with Sudan black and solubilising cellular components in sodiumhypochlorite. A arbitrary scale was established (ranging from 1 to 4) for selecting the best strains, acording to growth, staining with Sudan black and solubilising cellular material. 108 isolates rated higher than 2 were obtained by using this scale; 44 of these were selected for evaluating them in a balloon flask for their ability to grow in sucrose. Scheffe’s test grouped the isolates evaluated in the balloon flask for polymer production and productivity. The 6 best isolates were evaluated in a fermenter to determine their kinetic growth profiles, substrate consumption and polymer accumulation. Differential scanning calorimeter (DSC) was used on the recovered polymer for determining fusion temperature and the conclusion was reached that 2 strains accumulated poly--hydroxybutyrate (PHB) and another 4 accumulated hydroxy-butyrate copolymers and other monomer units. These 6 strains were molecularly characterised by partially sequencing the 16s rRNA ribosomal gene, localizing them in 4 clusters on the taxonomic tree

Efectos del desarrollo de la producción integrada en el sector citricola

A escala mundial se producirá, en el sector citrícola, un obligado reajuste de superficies y producciones, de acuerdo con la capacidad de absorción de los mercados. Para España pueden continuar las dificultades como consecuencia delos siguientes aspectos: liberalización del comercio mundial, con nuevas aperturas en el sector hortofrutícola, pérdida, de hecho, del principio de la preferencia comunitaria; fuerte presión exportadora de los países competidores, no sólo los mediterráneos sino también los del Hemisferio Sur. Por otra parte, ante este panorama mundial, es fácil prever que, con la intensa presión y concurrencia sobre unos mercados tan maduros comolos de la Unión Europea (U.E.), el consumidor contará con más opciones en la elección del producto, y ampliará en su comportamiento el campo de exigencias, entre las que se incluirán, además de los conceptos tradicionales de calidad, otros componentes como garantía sanitaria, producción y acondicionamiento respetuosos con el medio ambiente y la seguridad empresarial. El cumplimiento de tales exigencias, garantizado por unas normas, será el fundamento de una diferenciación de los productos, cuyo soporte básico puede ser la Producción Integrada (P.I.). En el presente trabajo se analiza la situación actual de la P.I. en el sector citrícola, su grado de desarrollo y cual es su influencia actual y previsible, tanto en la producción como en la comercialización. Del desarrollo actual de la P.I., según los Reglamentos publicados, se deduce la necesidad de reducir un número de logotipos y, si es posible, llegar a un logotipo único con posibilidad de una aceptación mayor en los canales comerciales

Una mirada al origen y las propiedades de los suelos magnésicos en el valle del cauca-colombia

Se estudiaron las relaciones Si/Mg y Ca/Mg, en tres transectos y 12 perfiles de suelos, con lluvias inferiores a 1400 mm anuales. Más de 15% de minerales ferromagnesianos en la fracción arena fueron garantía para la aparición de contenidos de Mg+2 mínimos de 5 Cmol (+)/kg en todos los paisajes. Variaciones anuales de la precipitación entre 800 y 1400 mm no influyeron en la variabilidad del magnesio de 5 a 41 Cmol (+)/kg. El Mg+2 aumentó en el sentido en que decreció la tasa de infiltración promedia. Los suelos con arcillas oxídicas acumularon SO4=, yeso en los poros y adolecieron de horizontes Bk; con influencia de piroclastos aumentaron Na+. Cuando presentaron Si / Mg and gt; 5 tuvieron menores concentraciones relativas de Mg+2 y Ca+2, excepto en familias esmectítica y caolinítica. Las aguas de riego presentaron C.E. and lt; 1 dS/m, la mayoría carbonato de sodio residual (CSR), y para casi todas se prevén aportes de magnesio al suelo. Hubo efecto específico en todos los paisajes; para Ca/Mg and lt; 2 se atenuó cuando el contenido de materia orgánica fue similar a 5% o con mineralogías caoliníticas; con mineralogías micáseas el efecto se dio desde relaciones Ca/Mg 2-3. Valores de Ca+2 and gt; 10 Cmol (+)/kg y pH ­ 7.5 inhibieron la acumulación de Na+. ABSTRACT A sigh over the origin and properties of magnesic soils in Valle del Cauca-Colombia. They were studied as a function of Si/Mg and Ca/Mg relations in three transect and 12 soil profiles where rain precipitation was lower than 1400 mm. More than 15% of ferromagnesian minerals in sand fraction allows at least a minimum Mg+2 content of 5 Cmol (+)/kg. Annual rain variations between 800 and 1400 mm had not influence in Mg+2 variability between 5 to 41 Cmol(+)/kg. Mg+2 contents had a tendency to increase as well as medium infiltration rate decrease. Magnesic soils with oxidic clays in general allowed accumulation of S04= ion, gypsum in pore space, and lacking of Bk horizons; but with piroclastic materials Na+ tended to increase. When showed Si / Mg and gt; 5, had relatively less Mg+2 y Ca+2 concentrations except in smectitic and kaolinitic families. All irrigation waters had C.E and lt; 1 dS/m, most of them residual sodium carbonate (RSC), and most of times they foresee high apports of magnesium to soils. There were specific effect in all landscapes; for Ca/Mg and lt; 2 was lessen when soil organic matter content was close to 5%, or if kaolinitic mineralogy; with micaceous mineralogy it occurred for Ca/Mg of 2-3. Ca+2 values greater than 10 Cmol (+)/kg and pH ­ 7.5 suppressed soil Na+ accumulation. Key words: magnesic soils, Mg specific effect, irrigation water quality

Anti-Black racism workshop during the Vera C. Rubin Observatory virtual 2021 Project and Community Workshop

Systemic racism is a ubiquitous theme in societies worldwide and plays a central role in shaping our economic, social, and academic institutions. The Vera C. Rubin Observatory is a major US ground-based facility based in Chile with international participation. The Observatory is an example of excellence and will deliver the largest survey of the sky ever attempted. Rubin's full scientific and social potential can not be attained without addressing systemic racism and associated barriers to equity, diversity, and inclusion (EDI). During Rubin's 2021 virtual Project and Community Workshop (PCW), the annual Rubin community-based meeting, an anti-Black racism workshop took place, facilitated by 'The BIPOC Project' organization. About 60 members from different parts of the Rubin ecosystem participated. We describe the motivation, organization, challenges, outcomes, and near- and long-term goals of this workshop.Comment: Contribution to appear in 'An Astronomical Inclusion Revolution: Advancing Diversity, Equity, and Inclusion in Professional Astronomy and Astrophysics', to be published by IOP ebook

Measurement of soft-drop jet observables in pp collisions with the ATLAS detector √ s = 13 TeV

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UA

Localization of bulk matter fields, the hierarchy problem and corrections to Coulomb's law on a pure de Sitter thick braneworld

In this paper we investigate the localization and mass spectra of matter fields with spin 0, 1 and 1/2 on a geometric thick brane generated by pure 4D and 5D positive cosmological constants without bulk scalar fields. This model possesses a 4D cosmological constant that can be made as small as one desires without fine-tuning it with the bulk cosmological constant. The RS model is obtained as an analytic continuation of the flat brane limit of this braneworld configuration when the Hubble parameter disappears. Within this inflating braneworld model it is possible to formulate a mechanism for obtaining TeV mass scales from Planck ones by adding a positive thin brane, where the Standard Model fields are trapped, at a distance y_2 from the origin, where the Planck thick brane resides. The brane separation must be of the same order than the inverse thickness parameter of the model in order for the mechanism to generate the desired hierarchy. This result is obtained by imposing the recovery of both the correct 4D gravitational couplings and the actually observed accelerated expansion of the universe in our de Sitter braneworld. Regarding the localization of matter in the purely geometric thick braneworld, for spin 0 massless and massive scalar fields as well as for spin 1 vector fields, the potentials of the Kaluza--Klein (KK) modes in thecorresponding Schroedinger equations are modified Poeschl-Teller potentials, which lead to the localization of the scalar and vector zero modes on the brane as well as to mass gaps in the mass spectra. We also compute the corrections to Coulomb's law coming from massive KK vector modes. For spin 1/2 fermions, we introduce the bulk mass term MF(z)\bar{\Psi}\Psi in the action and show that localization of the massless left-chiral fermion zero mode is feasible for two mass functions MF(z) with a finite/infinite number of massive KK bound states.Comment: 28 pages in latex, 19 figures, title modified according to substantial additions performed in the text of the manuscript. To appear in Phys Rev

Search for squarks and gluinos in final states with same-sign leptons and jets using 139 fb −1 of data collected with the ATLAS detector

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboración, si lo hubiereA search for supersymmetric partners of gluons and quarks is presented, involving signatures with jets and either two isolated leptons (electrons or muons) with the same electric charge, or at least three isolated leptons. A data sample of proton-proton collisions at √ s = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to a total integrated luminosity of 139 fb−1 , is used for the search. No significant excess over the Standard Model expectation is observed. The results are interpreted in simplified supersymmetric models featuring both R-parity conservation and R-parity violation, raising the exclusion limits beyond those of previous ATLAS searches to 1600 GeV for gluino masses and 750 GeV for bottom and top squark masses in these scenario

The ATLAS inner detector trigger performance in pp collisions at 13TeV during LHC Run 2

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboración, si lo hubiereThe designand performance of the inner detector trigger for the high level trigger of the ATLAS experiment at the Large Hadron Collider during the 2016–2018 data taking period is discussed. In 2016, 2017, and 2018 the ATLAS detector recorded35.6fb−1,46.9fb−1,and60.6fb−1 respectively of proton–proton collision data at a centre-of-mass energy of 13TeV. In order to deal with the very high interaction multiplicities per bunch crossing expected with the 13TeV collisions the inner detector trigger was redesigned during the long shutdown of the Large Hadron Collider from 2013 until 2015. An overview of these developments is provided and the performance of the tracking in the trigger for the muon, electron, tau and b-jet signatures is discussed. The high performance of the inner detector trigger with these extreme interaction multiplicities demonstrate show the inner detector tracking continues to lie at the heart of the trigger performance and is essential in enabling the ATLAS physics programm

Measurement of the azimuthal anisotropy of charged-particle production in Xe+Xe collisions at √ sNN = 5.44 TeV with the ATLAS detector

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UA