Exponential decay estimates for Singular Integral operators

The following subexponential estimate for commutators is proved |[|\{x\in Q: |[b,T]f(x)|>tM^2f(x)\}|\leq c\,e^{-\sqrt{\alpha\, t\|b\|_{BMO}}}\, |Q|, \qquad t>0.\] where $c$ and $\alpha$ are absolute constants, $T$ is a Calder\'on--Zygmund operator, $M$ is the Hardy Littlewood maximal function and $f$ is any function supported on the cube $Q$. It is also obtained |\{x\in Q: |f(x)-m_f(Q)|>tM_{1/4;Q}^#(f)(x) \}|\le c\, e^{-\alpha\,t}|Q|,\qquad t>0, where $m_f(Q)$ is the median value of $f$ on the cube $Q$ and M_{1/4;Q}^# is Str\"omberg's local sharp maximal function. As a consequence it is derived Karagulyan's estimate $$|\{x\in Q: |Tf(x)|> tMf(x)\}|\le c\, e^{-c\, t}\,|Q|\qquad t>0,$$ improving Buckley's theorem. A completely different approach is used based on a combination of "Lerner's formula" with some special weighted estimates of Coifman-Fefferman obtained via Rubio de Francia's algorithm. The method is flexible enough to derive similar estimates for other operators such as multilinear Calder\'on--Zygmund operators, dyadic and continuous square functions and vector valued extensions of both maximal functions and Calder\'on--Zygmund operators. On each case, $M$ will be replaced by a suitable maximal operator.Comment: To appear in Mathematische Annale

Wigner function for a particle in an infinite lattice

We study the Wigner function for a quantum system with a discrete, infinite dimensional Hilbert space, such as a spinless particle moving on a one dimensional infinite lattice. We discuss the peculiarities of this scenario and of the associated phase space construction, propose a meaningful definition of the Wigner function in this case, and characterize the set of pure states for which it is non-negative. We propose a measure of non-classicality for states in this system which is consistent with the continuum limit. The prescriptions introduced here are illustrated by applying them to localized and Gaussian states, and to their superpositions.Comment: 19 pages (single column), 7 figure

Perception of Fa by non-native listeners in a study abroad context

The present study aims at exploring the under-investigated interface between SA and L2 phonological development by assessing the impact of a 3-month SA programme on the pronunciation of a group of 23 Catalan/Spanish learners of English (NNSs) by means of phonetic measures and perceived FA measures. 6 native speakers (NS) in an exchange programme in Spain provided baseline data for comparison purposes. The participants were recorded performing a reading aloud task before (pre-test) and immediately after (post-test) the SA. Another group of 37 proficient non-native listeners, also bilingual in Catalan/Spanish and trained in English phonetics, assessed the NNS' speech samples for degree of FA. Phonetic measures consisted of pronunciation accuracy scores computed by counting pronunciation errors (phonemic deletions, insertions and substitutions, and stress misplacement). Measures of perceived FA were obtained with two experiments. In experiment 1, the listeners heard a random presentation of the sentences produced by the NSs and by the NNSs at pre-test and post-test and rated them on a 7-point Likert scale for degree of FA (1 = “native” , 7 = “heavy foreign accent”). In experiment 2, they heard paired pre-test/post-test sentences (i.e. produced by the same NNS at pre-test and posttest) and indicated which of the two sounded more native-like. Then, they stated their judgment confidence level on a 7-point scale (1 = “unsure”, 7 = “sure”). Results indicated a slight, non-significant improvement in perceived FA after SA. However, a significant decrease was found in pronunciation accuracy scores after SA. Measures of pronunciation accuracy and FA ratings were also found to be strongly correlated. These findings are discussed in light of the often reported mixed results as regards pronunciation improvement during short-term immersion

Territory and cooperativism: A spatial analysis of the Spanish region of Andalusia

This study seeks to identify the behavior of cooperative societies in Andalusia, as well as the environments in which their greater relative importance is evident. The weight of cooperative societies is significantly greater in Andalusia as compared to the rest of Spain. These organizations are noteworthy for acting under social, economic and environmental principles and values, and represent a potential opportunity for the region. The methodology applied for this purpose consists of spatial analysis using descriptive graphing techniques and application of spatial autocorrelation. Among the results obtained, a significant finding is these organizations’ defined behavior as opposed to that of mercantile or traditional businesses. In mapping the weight of cooperativism in Andalusia, this study enables a deeper understanding that could lead to improved design and execution of general and specific territorial policies, and with a greater guarantee of success

La situación de refugio y desplazamiento forzado en Ecuador

Entender esta situación de refugio y desplazamiento forzado en el Ecuador es permitirnos ver la conflictividad que acontece y tiene sus repercusiones más dramáticas en todo el cordón fronterizo. La región fronteriza entre Colombia y Ecuador se ha visto afectada por el conflicto armado en Colombia y con mayor intensidad en los últimos años con la implementación del Plan Colombia, lo cual ha traído graves consecuencias en términos de migraciones y derechos humanos. En la región ha existido una histórica injusticia social, concentración de poder y de riqueza en ciertos sectores, violencia generalizada y, para el caso de la frontera colombiana, está la presencia de actores armados; como consecuencia de ello, se ha presentado una degradación que se expresa en la violación del Derecho Internacional Humanitario por parte de los actores armados, en una violencia estatal que desconoce los derechos de las comunidades afectadas -especialmente etnias y afro descendientes-, y en éstas una falta de identidad y temor

What is a scientific experiment?: The impact of a professional development course on teachers’ ability to design an inquiry-based science curriculum

Designing inquiry-based science lessons can be a challenge for secondary school teachers. In this study we evaluated the development of in-service teachers’ lesson plans as they took part in a 10-month professional development course in Peru which engaged teachers in the design of inquiry-based lessons. At the beginning, most teachers designed either confirmatory or structured inquiry activities. As the course progressed, however, they started designing guided and open inquiry lesson plans. We found four factors that accounted for this change: re-evaluating the need for lab materials, revising their views on the nature of science, engaging in guided and open inquiry activities themselves, and trying out inquiry-based lessons with their own students. Our results point to the importance of engaging teachers in prolonged and varied opportunities for inquiry as part of teacher education programs in order to achieve the challenge of changing teachers’ views and practices in science education.Fil: Pérez, María del Carmen B.. Universidad de Piura; PerúFil: Furman, Melina Gabriela. Universidad de San Andrés. Escuela de Educación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Comunicación en la Red de Bibliotecas y Archivos del CSIC

Sección: La RedTradicionalmente las bibliotecas y archivos han jugado un papel importante en la estrategia de comunicación de las instituciones a las que sirven, siendo de gran relevancia para garantizar la difusión y el acceso a los recursos disponibles. La política de difusión ha ido evolucionando en los últimos años, en parte, gracias a la adopción de las herramientas 2.0, modificando de forma sustancial la manera de comunicación y difusión, abriendo nuevos modelos y facilitando un acercamiento rápido y de más calidad a los usuarios.N

Physiological characterization of drought stress response and expression of two transcription factors and two LEA genes in three Prunus genotypes

Global warming has led to a progressive decrease in rainfall, which is reflected by a reduction of water resources in the soil and a negative effect on crop production in Mediterranean areas. Under drought stress, many plants react by inducing a different series of responses at both physiological and molecular levels, allowing them to survive for a variable period of time. Therefore, in order to understand the response of roots to drought conditions, the genotypes peach × almond ‘Garnem’ [P. amygdalus Batsch × P. persica (L.) Batsch] and their progeny, the hybrid ‘P.2175’ × ‘Garnem’-3 and OP-‘P.2175’ (P. cerasifera Ehrh.) were subjected to a period of water deficit. Drought conditions with a subsequent re-watering period were tested for potted plants for one month. Stomatal conductance and leaf water potential were measured to monitor the plant physiological responses. Significant differences among the drought stress and drought stress recovery treatments and among the genotypes were observed. In addition, four genes related to the ABA biosynthesis pathway were studied for their expression by RT-qPCR: an AN20/AN1 zinc finger protein (ppa012373m); a bZIP transcription factor (ppa013046m); a dehydrin (ppa005514m) and a LEA protein (ppa008651m). Their expression profiles correlated with our physiological results of drought response, being higher in roots than in phloem tissue. In general, the expression of the four studied genes was higher after 15 days under drought conditions. Under drought and recovery conditions, the zinc finger and bZIP transcription factors showed significant differences in their relative expression levels from LEA and dehydrin. These results suggest the role of LEA and dehydrin in the regulatory response to drought stress in Prunus genotypes. Therefore, the dehydrin and the protein LEA might be potential biomarkers to select rootstocks for tolerance to drought conditions.We wish to thank Michael Glenn for helpful comments and ideas on the ash content discussion. This work was supported by RTA2014-00062 from the Instituto Nacional de Investigación y Tecnología Agraria (INIA) and by the Research Group A12 of Aragon, Spain. We kindly appreciate the FPI-INIA 2012 grant for B. Bielsa

Autophagy is activated and involved in cell death with participation of cathepsins during stress-induced microspore embryogenesis in barley

Microspores are reprogrammed towards embryogenesis by stress. Many microspores die after this stress, limiting the efficiency of microspore embryogenesis. Autophagy is a degradation pathway that plays critical roles in stress response and cell death. In animals, cathepsins have an integral role in autophagy by degrading autophagic material; less is known in plants. Plant cathepsins are papain-like C1A cysteine proteases involved in many physiological processes, including programmed cell death. We have analysed the involvement of autophagy in cell death, in relation to cathepsin activation, during stress-induced microspore embryogenesis in Hordeum vulgare. After stress, reactive oxygen species (ROS) and cell death increased and autophagy was activated, including HvATG5 and HvATG6 up-regulation and increase of ATG5, ATG8, and autophagosomes. Concomitantly, cathepsin L/F-, B-, and H-like activities were induced, cathepsin-like genes HvPap-1 and HvPap-6 were up-regulated, and HvPap-1, HvPap-6, and HvPap-19 proteins increased and localized in the cytoplasm, resembling autophagy structures. Inhibitors of autophagy and cysteine proteases reduced cell death and promoted embryogenesis. The findings reveal a role for autophagy in stress-induced cell death during microspore embryogenesis, and the participation of cathepsins. Similar patterns of activation, expression, and localization suggest a possible connection between cathepsins and autophagy. The results open up new possibilities to enhance microspore embryogenesis efficiency with autophagy and/or cysteine protease modulators.España, MINECO AGL2014-52028-R and AGL2017-82447-