EARNINGS MANAGEMENT AS AN EXPLANATION OF THE EQUITY ISSUE PUZZLE

The poor stock price performance of firms that raise capital through seasoned equity offerings is one of the recent puzzles in financial literature. In this study we investigate whether pre-issue earnings management can explain these results for rights issues in Spain. Consistent with this explanation, we notice that firms¿ issuing rights make use of discretionary accruals to report higher earnings prior to the offering. Most interestingly, the decrease in discretionary accruals the years following the offering explains the underperformance in stock returns.Corporate Finance, Seasoned Equity Offerings, Earnings Management, Accounting Accruals

Isolation of Ribosomal Particles from the Unicellular Cyanobacterium Synechocystis sp. PCC 6803

Isolation of ribosomal particles is an essential step in the study of ribosomal components as well as in the analysis of trans-acting factors that interact with the ribosome to regulate protein synthesis and modulate the expression profile of the cell in response to different environmental conditions. In this protocol, we describe a procedure for the isolation of 70S ribosomes from the unicellular cyanobacterium Synechocystis sp. PCC 6803 (hereafter Synechocystis). We have successfully used this protocol in our study of the cyanobacterial ribosomal-associated protein LrtA, which is a homologue of bacterial HPF (hibernation promoting factor) (Galmozzi et al., 2016).España, Junta de Andalucía grant P07-CVI-02792 and group BIO-284España, MINECO y Fondo Social Europeo grant BFU2013-41712-

Multidomain Network Based on Programmable Networks: Security Architecture

This paper proposes a generic security architecture designed for a multidomain and multiservice network based on programmable networks. The multiservice network allows users of an IP network to run programmable services using programmable nodes located in the architecture of the network. The programmable nodes execute codes to process active packets, which can carry user data and control information. The multiservice network model defined here considers the more pragmatic trends in programmable networks. In this scenario, new security risks that do not appear in traditional IP networks become visible. These new risks are as a result of the execution of code in the programmable nodes and the processing of the active packets. The proposed security architecture is based on symmetric cryptography in the critical process, combined with an efficient manner of distributing the symmetric keys. Another important contribution has been to scale the security architecture to a multidomain scenario in a single and efficient way.Publicad

IS THE MARKET OVER-OPTIMISTIC ABOUT THE PROSPECTS OF FIRMS THAT ISSUE EQUITY? EVIDENCE FOR THE SPANISH MARKET

Previous evidence has documented that equity issuers underperform in the long-run. One possible explanation is that investors have overoptimistic expectations regarding future earnings and the underperformance occurs as these expectations are corrected over time. Our central focus is to test this hypothesis for Spanish rights issuing firms, for that, firstly we examine analysts? predictions about future earnings of these companies. We observe that forecasts are unusually favourable and, moreover, the post-offering underperformance is most pronounced when analyst predictions have higher optimistic bias. Secondly, we study the market response to issuing firms? earnings announcements in the post-offering period observing a significant negative reaction. So the evidence in this paper is consistent with the excessive optimism hypothesis about issuing firms. Evidencia previa ha documentado que las empresas que amplían capital experimentanrentabilidades anormales negativas en el largo plazo. Una posible explicación es que losinversores tienen expectativas excesivamente optimistas sobre los beneficios futuros de estascompañías y la evolución observada se debe a la corrección gradual de este exceso deoptimismo. El principal objeto de este trabajo es contrastar esta hipótesis para las emisionescon derechos en el mercado español. Para ello, en primer lugar se examinan los pronósticos delos analistas sobre los beneficios futuros de las empresas emisoras. Se observa que laspredicciones para estas compañías son inusualmente favorables y, además, la peor evolución alargo plazo es más pronunciada cuando las predicciones son más optimistas. En segundolugar, se estudia la reacción del mercado a los anuncios de beneficios de las compañíasemisoras los años siguientes a la oferta, observando una reacción significativamente negativa.Por tanto, la evidencia aportada en este trabajo es consistente con la hipótesis de expectativasexcesivamente optimistas sobre las empresas que deciden ampliar capital.Finanzas corporativas, ampliaciones de capital, predicciones de beneficios Corporate Finance, Seasoned Equity Offerings, Earnings Forecasting.

Microbiota intestinal, relación con la obesidad e influencia de los probióticos y prebióticos

Introducción: la obesidad es un problema de salud pública que se debe a un balance positivo entre las calorías ingeridas y las consumidas. El IMC deseable, valor que se emplea para evaluar el peso corporal, depende de la edad y para adultos de edades comprendidas entre 25 y 34 años estaría entre 20 y 25 kg/m2. Por otra parte, la microbiota intestinal forma una comunidad compleja de microorganismos que puede jugar un papel importante en la modulación del peso corporal del hospedador. Justificación: la importancia de la obesidad como causa de patologías crónicas, así como su aumento progresivo en los países desarrollados han obligado a la comunidad científica a buscar estrategias para combatirla, entre ellas la modulación de la microbiota intestinal. Objetivo: hacer una revisión de la literatura científica sobre el papel potencial de la microbiota intestinal en la modulación del peso corporal y la función de los probióticos y prebióticos en el mantenimiento de la misma. Material y métodos: se ha realizado una revisión bibliográfica, utilizando como sistema de búsqueda Google Académico seleccionando las revisiones realizadas entre los años 2006-2016 que trataban del tema que nos ocupa. Las palabras clave han sido: microbiota, obesidad, probióticos, prebióticos, salud, obesity, microbiota, health, probiotics, prebiotics. Resultados: se han analizado 12 artículos de revisión. La microbiota intestinal se considera uno de los factores que influyen en la modulación del peso corporal. Cada individuo tiene una microbiota única y su composición se puede modificar por medio de componentes presentes en la dieta, como prebióticos y probióticos. Estudios metagenómicos han determinado la existencia de diferencias entre la microbiota de individuos obesos, con mayor capacidad de recuperar energía de la dieta, y delgados. Conclusiones: la posibilidad de manipular la microbiota intestinal mediante probióticos y prebióticos se contempla como una posible estrategia para modular el peso corporal y combatir la obesidadGrado en Enfermerí

NsrR1, a Nitrogen stress-repressed sRNA, contributes to the regulation of nblA in Nostoc sp. PCC 7120

Small regulatory RNAs (sRNAs) are currently considered as major post-transcriptional regulators of gene expression in bacteria. The interplay between sRNAs and transcription factors leads to complex regulatory networks in which both transcription factors and sRNAs may appear as nodes. In cyanobacteria, the responses to nitrogen availability are controlled at the transcriptional level by NtcA, a CRP/FNR family regulator. In this study, we describe an NtcA-regulated sRNA in the cyanobacterium Nostoc sp. PCC 7120, that we have named NsrR1 (nitrogen stress repressed RNA1). We show sequence specific binding of NtcA to the promoter of NsrR1. Prediction of possible mRNA targets regulated by NsrR1 allowed the identification of nblA, encoding a protein adaptor for phycobilisome degradation under several stress conditions, including nitrogen deficiency. We demonstrate specific interaction between NsrR1 and the 5′-UTR of the nblA mRNA, that leads to decreased expression of nblA. Because both NsrR1 and NblA are under transcriptional control of NtcA, this regulatory circuit constitutes a coherent feed-forward loop, involving a transcription factor and an sRNA.Agencia Estatal de Investigación (AEI) BFU2016-74943- C2-1-PMinisterio de Economía y Competitividad BFU2013-48282-C2-1-P, BES-2014- 06848

Walking as physical exercise in Fibromyalgia: an elicitation study from the Theory of Planned Behavior

Este estudio corresponde a la primera fase de investigación formativa recomendada en la teoría de la Acción Planeada para desarrollar una intervención. Nuestros objetivos son identificar las creencias modales sobre la realización de una pauta de ejercicio en personas con fibromialgia, probar los ítems para la evaluación directa de los constructos predictivos y explorar sus relaciones con la conducta. Evaluamos a 46 mujeres con fibromialgia. El análisis de contenido mostró un mayor número de consecuencias positivas que negativas asociadas a la ejecución de la pauta de ejercicio (creencias comportamentales); la familia y los amigos son los referentes importantes (creencias normativas) y se detectaron factores facilitadores e inhibidores de la ejecución de la conducta de ejercicio, relacionados con aspectos de la fibromialgia (creencias de control) como el dolor, la fatiga y el estado de ánimo. El índice de consistencia interna más bajo fue el de la escala de norma subjetiva (α= .78). Los resultados confirman el sedentarismo de la muestra (conducta previa: Media=3.67; rango=1-7) aunque también sugieren que estas personas tienen intención de realizar la conducta (Media= 5.67). Las relaciones obtenidas entre los constructos son las esperadas desde la teoría, apoyando la pertinencia de aplicarla en la conducta y población seleccionada

Studying Daub. Orientations for the Macroscopic Analysis of Earth Building Fragments in Archaeology

Research on hardened daub fragments provides highly relevant data on the building activities of past societies. Unfortunately, in many cases these elements are not considered relevant research objects, resulting in a very important loss of information for archaeology. There is still a long way to go in the studies of earth building remains, the vast majority of which have focused on assemblages coming from specific sites. Likewise, a good number of these studies carried out from a macroscopic approach either have not published the methodology used or barely offer some considerations about it. This article approaches the methodological procedures for their analysis through direct observation, while hoping to contribute to making these remains more visible and to facilitate and promote their study. This methodological proposal can be applicable to materials of different composition and from very different contexts, chronologies, and origins.La investigación sobre los restos constructivos de barro endurecido proporciona datos de gran relevancia sobre las actividades constructivas y las formas arquitectónicas de las sociedades del pasado. Por desgracia, todavía en muchos casos estos elementos no suelen ser considerados como un objeto de investigación relevante, suponiendo para la arqueología una pérdida muy importante de información que ya no es recuperable. Todavía queda un largo camino por recorrer en los estudios de restos constructivos de barro, la gran mayoría de los cuales se han centrado en conjuntos concretos. Asimismo, buena parte de estos estudios realizados desde una aproximación macroscópica, o no han publicado la metodología empleada, o apenas ofrecen algunas consideraciones sobre la misma. Con este artículo abordamos a modo de propuesta los procedimientos metodológicos necesarios para su análisis mediante la observación directa, a la vez que esperamos contribuir a visibilizar, facilitar y promover el estudio de estas evidencias. Esta propuesta metodológica puede ser transversal, aplicable a materiales de distinta composición y procedentes de contextos, cronologías y procedencias muy diversas. Si aspiramos a que las investigaciones sobre restos constructivos de barro se normalicen y sean cada vez más frecuentes, necesitamos que se preste una atención mayor a la metodología que ha de emplearse en su estudio. Esto también posibilitará que se dialogue acerca de la misma, para enriquecerla, mejorarla y mantenerla actualizada respecto a los avances que se producen en otras aproximaciones y técnicas analíticas que pueden acompañar a este estudio macroscópico, para profundizar así en el conocimiento de la construcción en el pasado y, de este modo, de las sociedades que la llevaron a cabo.This article was developed during a postdoctoral Juan de la Cierva-formación contract (FJC2019-039469-I) from the Spanish Ministerio de Ciencia e Innovación, at the Institut Català d'Arqueologia Clàssica (ICAC, Tarragona)

The Integrity of the Cell Wall and Its Remodeling during Heterocyst Differentiation Are Regulated by Phylogenetically Conserved Small RNA Yfr1 in Nostoc sp. Strain PCC 7120

Yfr1 is a strictly conserved small RNA in cyanobacteria. A bioinformatic prediction to identify possible interactions of Yfr1 with mRNAs was carried out by using the sequences of Yfr1 from several heterocyst-forming strains, including Nostoc sp. strain PCC 7120. The results of the prediction were enriched in genes encoding outer membrane proteins and enzymes related to peptidoglycan biosynthesis and turnover. Heterologous expression assays with Escherichia coli demonstrated direct interactions of Yfr1 with mRNAs of 11 of the candidate genes. The expression of 10 of them (alr2458, alr4550, murC, all4829, all2158, mraY, alr2269, alr0834, conR, patN) was repressed by interaction with Yfr1, whereas the expression of amiC2, encoding an amidase, was increased. The interactions between Yfr1 and the 11 mRNAs were confirmed by site-directed mutagenesis of Yfr1. Furthermore, a Nostoc strain with reduced levels of Yfr1 had larger amounts of mraY and murC mRNAs, supporting a role for Yfr1 in the regulation of those genes. Nostoc strains with either reduced or increased expression of Yfr1 showed anomalies in cell wall completion and were more sensitive to vancomycin than the wild-type strain. Furthermore, growth in the absence of combined nitrogen, which involves the differentiation of heterocysts, was compromised in the strain overexpressing Yfr1, and filaments were broken at the connections between vegetative cells and heterocysts. These results indicate that Yfr1 is an important regulator of cell wall homeostasis and correct cell wall remodeling during heterocyst differentiation.IMPORTANCE Bacterial small RNAs (sRNAs) are important players affecting the regulation of essentially every aspect of bacterial physiology. The cell wall is a highly dynamic structure that protects bacteria from their fluctuating environment. Cell envelope remodeling is particularly critical for bacteria that undergo differentiation processes, such as spore formation or differentiation of heterocysts. Heterocyst development involves the deposition of additional layers of glycolipids and polysaccharides outside the outer membrane. Here, we show that a cyanobacterial phylogenetically conserved small regulatory RNA, Yfr1, coordinates the expression of proteins involved in cell wall-related processes, including peptidoglycan metabolism and transport of different molecules, as well as expression of several proteins involved in heterocyst differentiation.España Ministerio de Educación, Cultura y Deporte (FPU014/05123 and EST16-00088)España Ministerio de Economía y Competitividad BFU2013-48282-C2-1España Agencia Estatal de Investigación (AEI), Ministerio de Economía, Industria y Competitividad, both cofinanced by the Fondo Europeo de Desarrollo Regional (FEDER) BFU2016-74943-C2-1-

A combinatorial strategy of alternative promoter use during differentiation of a heterocystous cyanobacterium

Heterocystous cyanobacteria such as Nostoc sp. are filamentous photosynthetic organisms that, in response to nitrogen deficiency, undergo a differentiation process transforming certain, semi-regularly spaced cells into heterocysts, devoted to nitrogen fixation. During transition to a nitrogen-fixing regime, growth of most vegetative cells in the filament is temporarily arrested due to nutritional deprivation, but developing heterocysts require intense transcriptional activity. Therefore, the coexistence of arrested vegetative cells and actively developing prospective heterocysts relies on the simultaneous operation of somewhat opposite transcriptional programs. We have identified genes with multiple nitrogen-responsive transcriptional starts appearing in seemingly paradoxical combinations. For instance, sigA, encoding the RNA polymerase housekeeping sigma factor, is transcribed from one major nitrogen stress-repressed promoter and from a second, nitrogen stress-induced promoter. Here, we show that both promoters are expressed with complementary temporal dynamics. Using a gfp reporter we also show that transcription from the inducible promoter takes place exclusively in differentiating heterocysts and is already detected before any morphological or fluorescence signature of differentiation is observed. Tandem promoters with opposite dynamics could operate a compensatory mechanism in which repression of transcription from the major promoter operative in vegetative cells is offset by transcription from a new promoter only in developing heterocyst.Ministerio de Economía y Competitividad BFU2013-48282-C2-1Agencia Estatal de Investigación (AEI) BFU2016-74943-C2-1-PMinisterio de Educación, Cultura y Deportes FPU014/0512