A New Characterization of Fine Scale Diffusion on the Cell Membrane

We use a large single particle tracking data set to analyze the short time and small spatial scale motion of quantum dots labeling proteins in cell membranes. Our analysis focuses on the jumps which are the changes in the position of the quantum dots between frames in a movie of their motion. Previously we have shown that the directions of the jumps are uniformly distributed and the jump lengths can be characterized by a double power law distribution. Here we show that the jumps over a small number of time steps can be described by scalings of a {\em single} double power law distribution. This provides additional strong evidence that the double power law provides an accurate description of the fine scale motion. This more extensive analysis provides strong evidence that the double power law is a novel stable distribution for the motion. This analysis provides strong evidence that an earlier result that the motion can be modeled as diffusion in a space of fractional dimension roughly 3/2 is correct. The form of the power law distribution quantifies the excess of short jumps in the data and provides an accurate characterization of the fine scale diffusion and, in fact, this distribution gives an accurate description of the jump lengths up to a few hundred nanometers. Our results complement of the usual mean squared displacement analysis used to study diffusion at larger scales where the proteins are more likely to strongly interact with larger membrane structures.Comment: 18 pages, 7 figure

Changes in neuronal CycD/Cdk4 activity affect aging, neurodegeneration, and oxidative stress.

Mitochondrial dysfunction has been implicated in human diseases, including cancer, and proposed to accelerate aging. The Drosophila Cyclin-dependent protein kinase complex cyclin D/cyclin-dependent kinase 4 (CycD/Cdk4) promotes cellular growth by stimulating mitochondrial biogenesis. Here, we examine the neurodegenerative and aging consequences of altering CycD/Cdk4 function in Drosophila. We show that pan-neuronal loss or gain of CycD/Cdk4 increases mitochondrial superoxide, oxidative stress markers, and neurodegeneration and decreases lifespan. We find that RNAi-mediated depletion of the mitochondrial transcription factor, Tfam, can abrogate CycD/Cdk4's detrimental effects on both lifespan and neurodegeneration. This indicates that CycD/Cdk4's pathological consequences are mediated through altered mitochondrial function and a concomitant increase in reactive oxygen species. In support of this, we demonstrate that CycD/Cdk4 activity levels in the brain affect the expression of a set of 'oxidative stress' genes. Our results indicate that the precise regulation of neuronal CycD/Cdk4 activity is important to limit mitochondrial reactive oxygen species production and prevent neurodegeneration

CHANGES IN FLORISTIC COMPOSITION IN THE STATE FORESTS IN WORCESTER COUNTY (MASSACHUSETTS) OVER 34 YEARS

ABSTRACT CHANGES IN FOREST DIVERSITY OF STATE FOREST IN WORCESTER COUNTY, MASSACHUSETTS, OVER 34 YEARS PERIOD The forest in Massachusetts has changed since the earliest colonial settlement and today the floristic composition is more homogeneous. This study investigates the potential change in the floristic composition over thirty years in Worcester County State Forests. Shannon, richness and evenness indices for two periods were compared, and Jaccard index was used to analyze similarity in composition between the periods. The possible influence of severe weather events was also analyzed. It was found Changes in the floristic composition, but the magnitude of the changes were not statistically significant. The Jaccard similarity index showed statistically significant differences between north and south. There was also, significant differences between plots that experienced insects’ attack or snow/ice damage compared to plots with no pest/ice damage. The implications of the research findings indicate that diversity of the State Forest did not present statistically significant change. Petersham presented the highest diversity, while the lower value was for North Brookfield. The similarity of the forest did not change through the time, but there is significant difference between the north and the south[fa1] . [fa1

Relation between Brown Dwarfs and Exoplanets

One of the most debated subjects in Astronomy since the discovery of exoplanets is how can we distinguish the most massive of such objects from very-low mass stars like Brown Dwarfs (BDs)? We have been looking for evidences of a difference in physical characteristics that could be related to different formation processes. Using a new diagnostic diagram that compares the baryonic gravitational potential (BGP) with the distances from their host stars, we have classified a sample of 355 well-studied exoplanets according to their possible structures. We have then compared the exoplanets to a sample of 87 confirmed BDs, identifying a range in BGP that could be common to both objects. By analyzing the mass-radius relations (MRR) of the exoplanets and BDs in those different BGP ranges, we were able to distinguish different characteristic behaviors. By comparing with models in the literature, our results suggest that BDs and massive exoplanets might have similar structures dominated by liquid metallic hydrogen (LMH).Comment: Poster #149 from proceeding of The 19th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun; 06-10 June 2016, Uppsala, Swede

Hydrodynamic controls of morpho-sedimentary evolution in a rock-bounded mesotidal estuary. Tina Menor (N Spain)

The Tina Menor estuary is a highly confined incised valley with advanced sedimentary infilling. The outstanding feature of this estuary is its longitudinal zonation, which forms four segments from the outer to the inner limit: Mouth complex, Bay, Tidal flats and Upper channel. The innermost part of the Bay and the Tidal Flats (semi-reclaimed areas) are broader estuarine zones, whereas the Mouth Complex and outermost Bay are confined by narrow rocky outcrops. This paper explains the dynamics and sedimentary distribution of a highly confined and singular estuary, detailing the fluvial-tidal controls on the variations in water mixing (QF/QT). This estuary is largely of salt wedge type and the dynamics are characterised by recording currents (speed and direction) in the water column during a tidal cycle in a spring tide; this process consists of the tidal waves propagation and their dissipation upstream hypo-synchronously and the mixing of fresh and saline waters. The morphology, dynamics and sedimentary distributions have been integrated to develop a conceptual model that demonstrates the circulation within the estuary. The sinuous geometry of the estuarine valley and the Coriolis Effect detected, play a fundamental role in determining the morphology and sedimentary distribution. Consequently, this study provides an adequate overview of this type of confined mesotidal estuary, quite common in the eastern Atlantic coast.The mrophology, dynamics and sedimentary distributions have been integrated to develop a conceptual model that demonstrates the circulation within the estuary. The sinous geometry of the estuarine valley and the Coriolis effect detected, play  a fundamental role in determining the morphology and sedimentary distribution. Consequently, this study provides an adequate overview of this type of confined mesotidal estuary, quite common in the eastern Atlantic coast.El estuario de Tina Menor es un valle encajado altamente confinado y sedimentariamente en un avanzado estado de colmatación. Se caracteriza por su zonación longitudinal en cuatro segmentos bien diferenciados desde su sector más externo hasta el límite interior: Complejo de Desembocadura, Bahía, Llanuras Mareales y Canal Superior. El interior de la Bahía y las Llanuras Mareales de carácter fangoso (zonas semi-reclamadas) son las más extensas, mientras que el Complejo de Desembocadura y la parte externa de la Bahía, están estrechamente confinadas por afloramientos rocosos. Este trabajo explica la distribución dinámica y sedimentaria de un estuario singular y altamente confinado, detallando los controles fluviales-mareales en la variación de las mezclas de agua (QF/QT). Este estuario es en gran parte del tipo de cuña salina y la dinámica fue caracterizada por las medidas de corrientes (velocidad y dirección) realizadas en la columna de agua durante un ciclo mareal en marea viva; este proceso consiste en la propagación de las ondas de marea y su disipación de aguas arriba hiposincrónicamente y la mezcla de aguas dulces y salinas. La morfología, dinámica y las distribuciones sedimentarias, se han integrado para desarrollar un modelo conceptual que demuestre la circulación dentro del estuario. La geometría sinuosa del valle estuarino y la detección del efecto de Coriolis, juegan un rol fundamental para determinar la distribución morfologica y sedimentaria. Consecuentemente, este estudio proporciona un visión adecuada de este tipo de estuarios mesomareales confinados, tan comunes en las costas atlánticas orientales

Nutritional disorders

Different nutritional deficiencies or toxicities may limit bean development and yield. N and P deficiencies are the most frequent, although deficiency of minor elements and Al/Mn toxicity can reduce yields considerably. Nutritional problems are usually diagnosed by soil and plant tissue analyses and the observation of symptoms produced by nutritional disorders. Optimum pH for bean production varies between 6.5 and 7.5; within these limits, the majority of the plant nutrients have their max. availability. Color illustrations are given of the symptoms of plant deficiencies and toxicities. (CIAT)Diversas deficiencias o toxicidades nutricionales pueden limitar el desarrollo del frijol y su rendimiento. Las deficiencias de N y P son las mas frecuentes, aunque las de elementos menores y la toxicidad de Al y Mn pueden reducir considerablemente los rendimientos. Los problemas nutricionales se diagnostican mediante el analisis del suelo y del tejido vegetal, y la observacion de los sintomas producidos por desordenes nutricionales. El pH optimo para producir frijol fluctua entre 6.5 y 7.5; dentro de estos limites, la mayoria de los elementos nutritivos de la planta presentan su max. disponibilidad. Se presentan ilustraciones a color de los sintomas de deficiencia o toxicidad en las plantas. (CIAT

Industrias paleolíticas eolizadas en la región del Cabo de Peñas (Asturias)

[Resumen] En el borde costero de la región del Cabo Peñas ( Asturias ), se encuentran numerosos registros sedimentarios y prehist6ricos, particularmente del Paleolítico Inferior, que permiten una caracterización precisa entre la evolución litoral y los asentamientos humanos. En este trabajo, se estudian dos localizaciones prehistóricas de indudable interés: la punta de Cabo Peñas y El Otero ( Xagó ), donde vienen apareciendo útiles con signos evidentes de haber sido trabajados por el viento y que se encuentran asociados claramente al ambiente sedimentario. Se han sometido a análisis tipológicos y sedimentológicos, intentandose una aproximación cronológica.[Abstract] In the central and western coastal zone of the Cabo Peñas Asturias), there are several sedimentary and prehistoric records mainly from the Lower Palaeolithic allowing an accurate characterization between the littoral evolution and human establishment. In this work two interesting prehistoric sites are studied Cabo Peñas and El Otero ( Xagó ) where we met sorne eolized prehistoric industries associated to the sedimentary environment. Typologic and sedimentologic analysis were made and a chronology of the process was trie

Caracterización del interfaz forestal/urbano empleando LiDAR como herramienta para la estimación del riesgo de daños por incendios forestales

[EN] Galicia is a region in NW Spain which is usually affected by a high number of forest fires, and it should meet the current regulations regarding the distance between forests and buildings. This paper aims to identify and characterize woodlands and classify buildings according to their fire risk, for a 36 km2 area in Forcarei (Pontevedra, Spain). We used LiDAR data to generate three spatial models (DTM: Digital Terrain Model, DSM: Digital Surface Model and nDSM: Normalized Digital Surface Model) and two statistics to characterize the forest stands (density of dominant trees per hectare and their average height). The identification of forested areas was performed using an object-based classification method using the intensity image, the height model and an orthophotograph of the area, and a kappa coefficient of 0.82 was obtained in the validation. The woodlands were reclassified according to the magnitude of a possible fire, based on the density and the average height of the woodlands. The forest stands were mapped according to the magnitude of a possible fire and it was found that 1.18 km2 would be susceptible to a low magnitude fire, 3.75 km2 to a medium magnitude fire and 2.25 km2 to a fire of a high magnitude. Afterwards, it was determined whether the buildings in the area complied with the legislation relating to minimum distance from the forested areas (30 meters). For those that did not meet this distance, the risk of damage in case of a wildfire was calculated. The result was that 43.01% of buildings in the area complied with the regulations, 9.95% were located in a very low risk area, 25.74% in a low risk location, 12.37% in a medium risk area and 8.93% were in a high or very high risk area.S

El complejo de dunas eólicas de la Playa de Frouxeira (Meirás-Valdoviño, La Coruña)

[Resumen] Dentro del complejo dunar, situado en la parte posterior de la playa de Frouxeira, se han distinguido varios tipos de dunas : montículos aislados, remontantes, parabólicas y blow-outs y cartografiados en cuatro subzonas: dunas activas, subrecientes, remontantes y fósiles. Se establecen las características texturales de las arenas dunares y de playa, tanto granulométricas como a partir de los índices de correlación lineal entre los diferentes parámetros, además del contenido carbonatado. Finalmente, se determina la evolución sedimentaria y su relación con el resto de la cornisa cantábrica, mediante los datos prehistóricos asociados al medio de depósito[Abstract] Several coastal sand dunes are classified ( isolated mounds, climbing, parabolic and blow-outs ) and they are distributed in four areas: active, subrecent, climbing and fossil ones. Textural patterns as well granulometric parameters as lineal correlation index among them are stablished. Finally, the sedimentary evolution is determlnated by the help of the prehistoric information from the Asturian and Cantabrian region

Phosphorylation-mediated unfolding of a KH domain regulates KSRP localization via 14-3-3 binding

The AU-rich element (ARE)-mediated mRNA-degradation activity of the RNA binding K-homology splicing regulator protein (KSRP) is regulated by phosphorylation of a serine within its N-terminal KH domain (KH1). In the cell, phosphorylation promotes the interaction of KSRP and 14-3-3ζ protein and impairs the ability of KSRP to promote the degradation of its RNA targets. Here we examine the molecular details of this mechanism. We report that phosphorylation leads to the unfolding of the structurally atypical and unstable KH1, creating a site for 14-3-3ζ binding. Using this site, 14-3-3ζ discriminates between phosphorylated and unphosphorylated KH1, driving the nuclear localization of KSRP. 14-3-3ζ –KH1 interaction regulates the mRNA-decay activity of KSRP by sequestering the protein in a separate functional pool. This study demonstrates how an mRNA-degradation pathway is connected to extracellular signaling networks through the reversible unfolding of a protein domain.European Molecular Biology Organization 240-2005Italian CIPE-200