Nonuniversality in the pair contact process with diffusion

We study the static and dynamic behavior of the one dimensional pair contact process with diffusion. Several critical exponents are found to vary with the diffusion rate, while the order-parameter moment ratio m=\bar{rho^2} /\bar{rho}^2 grows logarithmically with the system size. The anomalous behavior of m is traced to a violation of scaling in the order parameter probability density, which in turn reflects the presence of two distinct sectors, one purely diffusive, the other reactive, within the active phase. Studies restricted to the reactive sector yield precise estimates for exponents beta and nu_perp, and confirm finite size scaling of the order parameter. In the course of our study we determine, for the first time, the universal value m_c = 1.334 associated with the parity-conserving universality class in one dimension.Comment: 9 pages, 5 figure

The chaperonin CCT inhibits assembly of α-synuclein amyloid fibrils by a specific, conformation-dependent interaction

The eukaryotic chaperonin CCT (chaperonin containing TCP-1) uses cavities built into its double-ring structure to encapsulate and to assist folding of a large subset of proteins. CCT can inhibit amyloid fibre assembly and toxicity of the polyQ extended mutant of huntingtin, the protein responsible for Huntington's disease. This raises the possibility that CCT modulates other amyloidopathies, a still-unaddressed question. We show here that CCT inhibits amyloid fibre assembly of α-synuclein A53T, one of the mutants responsible for Parkinson's disease. We evaluated fibrillation blockade in α-synuclein A53T deletion mutants and CCT interactions of full-length A53T in distinct oligomeric states to define an inhibition mechanism specific for α-synuclein. CCT interferes with fibre assembly by interaction of its CCT and CCT 3 subunits with the A53T central hydrophobic region (NAC). This interaction is specific to NAC conformation, as it is produced once soluble α-synuclein A53T oligomers form and blocks the reaction before fibres begin to grow. Finally, we show that this association inhibits α-synuclein A53T oligomer toxicity in neuroblastoma cells. In summary, our results and those for huntingtin suggest that CCT is a general modulator of amyloidogenesis via a specific mechanism.Ministerio de Economía RYC- 2011-08746 , RTC-2015-3309-1 y BFU2016-75984Ministerio de Salud CP10/00527Comunidad de Madrid S2013/MIT-280

Aplicaciones de enmiendas orgánicas y microorganismos para optimizar parámetros del suelo y rendimiento del nogal pecanero

El cultivo de nogal pecanero en el estado de Chihuahua es una actividad en crecimiento. Las zonas donde se cultiva el nogal presentan una serie de problemas, como son falta de agua, alta salinidad y alto contenido de sodio, baja nutrición en los suelos, bajo contenido de materia orgánica, entre otras, lo que provoca una disminución de la producción de nuez pecanera. El objetivo del presente estudio fue evaluar las aplicaciones al suelo de enmiendas cálcicas, orgánicas y microorganismos para los componentes del rendimiento y contenido de macronutrientes en el nogal pecanero. Los factores que se aplicaron y que influyeron en todas las variables de respuesta de los componentes de rendimiento y contenido de macronutrientes son: Ca/CaCO3 75.0 y 147.4 kg ha-1, Hongos Micorrízicos 20.7 y 17.2 kg ha-1, Humus Liquida (Hu_Liq) 750 y 1083.1 L ha-1, Humus Solida (Hu_sol) 1671.2 y 1632.6 kg ha-1. Las variables de respuesta que se evaluaron y fueron las más importantes para los componentes del rendimiento son: porcentaje de nuez comestible, nueces por kilogramo y peso promedio de nuez. Mientras que para el contenido de macronutrientes del suelo en nogal fueron: calcio/porcentaje de saturación de bases, calcio/(potasio+magnesio) y sodio

Sandpiles with height restrictions

We study stochastic sandpile models with a height restriction in one and two dimensions. A site can topple if it has a height of two, as in Manna's model, but, in contrast to previously studied sandpiles, here the height (or number of particles per site), cannot exceed two. This yields a considerable simplification over the unrestricted case, in which the number of states per site is unbounded. Two toppling rules are considered: in one, the particles are redistributed independently, while the other involves some cooperativity. We study the fixed-energy system (no input or loss of particles) using cluster approximations and extensive simulations, and find that it exhibits a continuous phase transition to an absorbing state at a critical value zeta_c of the particle density. The critical exponents agree with those of the unrestricted Manna sandpile.Comment: 10 pages, 14 figure

¿cómo responder a nuestras preguntas de investigación de forma específica y no morir en el intento? Parte X: ¿dónde y cómo busco información científica fiable y de calidad?

Indexación: Scopus.¿Cómo responder a nuestras preguntas de investigación de forma específica y no morir en el intento? Parte X: ¿Dónde y cómo busco información científica fiable y de calidad? How to answer our research questions specifically and not die trying? Part X: where and how do i look for reliable and quality scientific information?https://www.resed.es/como-responder-a-nuestras-preguntas-de-investigacion-de-forma-especifica-y-no-morir-en-el-intento-parte-x-donde-y-como-busco-informacion-cientifica-fiable-y-de-calidad937?AspxAutoDetectCookieSupport=

Local inhibition of nitrogen fixation and nodule metabolism in drought-stressed soybean

Drought stress is a major factor limiting symbiotic nitrogen fixation (NF) in soybean crop production. However, the regulatory mechanisms involved in this inhibition are still controversial. Soybean plants were symbiotically grown in a split-root system (SRS), which allowed for half of the root system to be irrigated at field capacity while the other half remained water deprived. NF declined in the water-deprived root system while nitrogenase activity was maintained at control values in the well-watered half. Concomitantly, amino acids and ureides accumulated in the water-deprived belowground organs regardless of transpiration rates. Ureide accumulation was found to be related to the decline in their degradation activities rather than increased biosynthesis. Finally, proteomic analysis suggests that plant carbon metabolism, protein synthesis, amino acid metabolism, and cell growth are among the processes most altered in soybean nodules under drought stress. Results presented here support the hypothesis of a local regulation of NF taking place in soybean and downplay the role of ureides in the inhibition of NF

Thermal and light irradiation effect on the electrocatalytic performance of Hemoglobin modified Co3O4-g-C3N4 nanomaterials for oxygen evolution reaction

The oxygen evolution reaction (OER) plays a key role in the water splitting process and a high energy conversion efficiency is essential for the definitive advance of hydrogen-based technologies. Unfortunately, the green and sustainable development of electrocatalysts for water oxidation is nowadays a real challenge. Herein, a successful mechanochemical method is proposed for the synthesis of a novel hemoglobin (Hb) modified Co3O4/g-C3N4 composite nanomaterial. The controlled incorporation of cobalt entities as well as Hb functionalization, without affecting the g-C3N4 nanoarchitecture, was evaluated using different physicochemical techniques, such as X-ray diffraction, N2-physisorption, scanning electron microscopy, UV-visible spectroscopy and X-ray photoelectron spectroscopy. The beneficial effect of the resulting ternary bioconjugate together with the influence of the temperature and light irradiation was investigated by electrochemical analysis. At 60 °C and under light exposition, this electrocatalyst requires an overpotential of 370 mV to deliver a current density of 10 mA·cm−2, showing a Tafel slope of 66 mV·dec−1 and outstanding long-term stability for 600 OER cycles. This work paves a way for the controlled fabrication of multidimensional and multifunctional bio-electrocatalysts

Confirmación de Argas neghmei (Ixodida: Argasidae) en Perú y reporte del carpintero andino (Colaptes rupicola) como nuevo hospedero

This report describes the finding of soft ticks (Ixodida, Argasidae) parasitizing two Andean flickers (Colaptes rupicola) from the Nuñoa district, Melgar province in Puno, Peru (14°31'11.77"S; 70°32'15.95''W; elevation 3967 m). A total of 29 larval ticks were collected directly from the birds and morphologically identified as Argas neghmei. Diagnosis was based on the larval morphology and confirmed by molecular analysis of the tick mitochondrial 16S rRNA gene. A sequence of 363 base pair of this gene showed to be 100% identical with sequences of A. neghmei from Argentina and Chile (GenBank: FJ853598 and DQ295781). This finding confirms the presence of A. neghmei in Peru and adds the Andean flicker as a new host for this species.Este informe describe el hallazgo de garrapatas blandas (Ixodida, Argasidae) parasitando a dos carpinteros andinos (Colaptes rupicola) provenientes del distrito de Nuñoa, provincia de Melgar en Puno, Perú (14°31’11.77"S; 70°32’15.95"W; 3967 m de altitud). Un total de 29 larvas de garrapatas fueron colectadas directamente de las aves y posteriormente identificadas morfológicamente como Argas neghmei. El diagnóstico fue basado en la morfología de las larvas y confirmado mediante el análisis molecular del gen 16S ARNr mitocondrial de la garrapata. Un fragmento de 363 pares de bases de este gen mostró una identidad del 100% con secuencias registradas para A. neghmei de Argentina y Chile (GenBank: FJ853598 y DQ295781). Este hallazgo confirma la presencia de A. neghmei en Perú y agrega al carpintero andino como nuevo hospedero para esta garrapata