V0 production ratios at LHCb and the alignment of its RICH detectors

The strangeness production ratios [bar wedge]/∧ and [bar wedge]/K0S are measured by the LHCb detector from 0.3 nb-1 of proton-proton collisions delivered by the Large Hadron Collider (LHC) at CERN with centre-of-mass energy √s = 0.9TeV and 1.8 nb-1 at √s = 7TeV. Both ratios are presented as a function of transverse momentum, pT, and rapidity, y, in the ranges 0.15 < pT < 2.50 GeV/c and 2.0 < y < 4.5. The ratios measured at the two energies are in good agreement in an overlapping region of rapidity loss, Δ y = ybeam - y, and are consistent with previous measurements. A review of the Standard Model is presented with emphasis on the diffculties in its application for predictions of physics at the LHC. Phenomenological models are introduced as the current state of the art for such predictions. Accurate models are required as an essential benchmark for future discoveries of physics beyond the Standard Model. LHCb's results represent a powerful test for these models in the soft QCD regime for processes including hadronisation. The ratio [bar wedge]/∧, measuring the transport of baryon number from the collision into the detector, is smaller in data than predicted, particularly at high rapidity. The ratio [bar wedge]/K0 S, measuring the baryon-to-meson suppression in strange quark hadronisation, is significantly larger than expected. The LHCb experiment is introduced, with particular focus on its Ring Imaging Cherenkov (RICH) detectors. The development and successful implementation of a method to align those RICH detectors is presented, using proton-proton collision data from the early running period of the Large Hadron Collider, which began in November 2009. The performance of the RICH detectors is investigated with preliminary analysis of the Cherenkov photon yield. The RICH mirror positions are monitored using an automated software control system, which has been running successfully since October 2008

Student Teachers’ Experiences with a Preparation-to-Practice Gap in Reading Instruction: A Preliminary Exploration and Implications for Teacher Preparation Faculty

Abstract Teacher educators and practitioners can agree that there are differences between knowing something in theory and knowing how to do something in a real classroom. This qualitative inquiry is anchored in evidence-based reading instruction as described by the National Reading Panel (2000) which emphasizes systematic, explicit instructional and teaching enhancements to support diverse students’ learning in multi-tier general educational classrooms. Specifically, this study investigated how student teachers applied their knowledge of research based reading methods in general education classrooms during their capstone field experience at the end of their undergraduate program, hereafter called student teaching

Monoclonal Antibody Identification of Subpopulations of Cerebral Cortical Neurons Affected in Alzheimer disease

Neuronal degeneration is one of the hallmarks of Alzheimer disease (AD). Given the paucity of molecular markers available for the identification of neuronal subtypes, the specificity of neuronal loss within the cerebral cortex has been difficult to evaluate. With a panel of four monoclonal antibodies (mAbs) applied to central nervous system tissues from AD patients, we have immunocytochemically identified a population of vulnerable cortical neurons; a subpopulation of pyramidal neurons is recognized by mAbs 3F12 and 44.1 in the hippocampus and neocortex, and clusters of multipolar neurons in the entorhinal cortex reactive with mAb 44.1 show selective degeneration. Closely adjacent stellate-like neurons in these regions, identified by mAb 6A2, show striking preservation in AD. The neurons recognized by mAbs 3F12 and 44.1, to the best of our knowledge, do not comprise a single known neurotransmitter system. mAb 3A4 identifies a phosphorylated antigen that is undetectable in normal brain but accumulates early in the course of AD in somas of vulnerable neurons. Antigen 3A4 is distinct from material reactive with thioflavin S or antibody generated against paired helical filaments. Initially, antigen 3A4 is localized to neurons in the entorhinal cortex and subiculum, later in the association neocortex, and, ultimately in cases of long duration, in primary sensory cortical regions. mAb 3F12 recognizes multiple bands on immunoblots of homogenates of normal and Ad cortical tissues, whereas mAb 3A4 does not bind to immunoblots containing neurofilament proteins or brain homogenates from AD patients. Ultrastructurally, antigen 3A4 is localized to paired-helical filaments. Using these mAbs, further molecular characterization of the affected cortical neurons is now possible

GABAergic neurons comprise a major cell type in rodent visual relay nuclei: an immunocytochemical study of pretectal and accessory optic nuclei.

The enzyme glutamic acid decarboxylase (GAD) has been localized in sections of rodent brains (gerbil, rat) using conventional immunocytochemical techniques. Our findings demonstrate that large numbers of GAD-positive neurons and axon terminals (puncta) are present in the visual relay nuclei of the pretectum and the accessory optic system. The areas of highest density of these neurons are in the nucleus of the optic tract (NOT) of the pretectum, the dorsal and lateral terminal accessory optic nuclei (DTN, LTN), the ventral and dorsal subdivisions of the medial terminal accessory optic nucleus (MTNv, MTNd), and the interstitial nucleus of the posterior fibers of the superior fasciculus (inSFp). The findings indicate that 27% of the NOT neurons are GAD-positive and that these neurons are distributed over all of the NOT except the most superficial portion of the NOT caudally. The GAD-positive neurons of the NOT are statistically smaller (65.9 microns2) than the total population of neurons of the NOT (84.3 microns2) but are otherwise indistinguishable in shape from the total neuron population. The other visual relay nuclei that have been analyzed (DTN, LTN, MTNv, MTNd, inSFp) are similar in that from 21% to 31% of their neurons are GAD-positive; these neurons are smaller in diameter and are more spherical than the total populations of neurons. The data further show that a large proportion of the neurons in these visual relay nuclei are contacted by GAD-positive axon terminals. It is estimated that approximately one-half of the neurons of the NOT and the terminal accessory optic nuclei receive a strong GABAergic input and have been called "GAD-recipient neurons". Further, the morphology of the GAD-positive neurons combined with their similar distribution to the GAD-recipient neurons suggest that many of these neurons are acting as GABAergic, local circuit neurons. On the other hand, the large number of GAD-positive neurons in the NOT and MTN (20-30%) in relation to estimates of projection neurons (75%) presents the possibility that some may in fact be projection neurons. The overall findings provide morphological evidence which supports the general conclusion that GABAergic neurons play a significant role in modulating the output of the visually related NOT and terminal accessory optic nuclei

Réplica

Aprovada pel Plenari del Consell Municipal de 17-09-1993Digitalitzat pel SEDA

Spatial heterogeneity enhances and modulates excitability in a mathematical model of the myometrium

The muscular layer of the uterus (myometrium) undergoes profound changes in global excitability prior to parturition. Here, a mathematical model of the myocyte network is developed to investigate the hypothesis that spatial heterogeneity is essential to the transition from local to global excitation which the myometrium undergoes just prior to birth. Each myometrial smooth muscle cell is represented by an element with FitzHugh–Nagumo dynamics. The cells are coupled through resistors that represent gap junctions. Spatial heterogeneity is introduced by means of stochastic variation in coupling strengths, with parameters derived from physiological data. Numerical simulations indicate that even modest increases in the heterogeneity of the system can amplify the ability of locally applied stimuli to elicit global excitation. Moreover, in networks driven by a pacemaker cell, global oscillations of excitation are impeded in fully connected and strongly coupled networks. The ability of a locally stimulated cell or pacemaker cell to excite the network is shown to be strongly dependent on the local spatial correlation structure of the couplings. In summary, spatial heterogeneity is a key factor in enhancing and modulating global excitability

Labor-associated gene expression in the human uterine fundus, lower segment, and cervix

Background Preterm labor, failure to progress, and postpartum hemorrhage are the common causes of maternal and neonatal mortality or morbidity. All result from defects in the complex mechanisms controlling labor, which coordinate changes in the uterine fundus, lower segment, and cervix. We aimed to assess labor-associated gene expression profiles in these functionally distinct areas of the human uterus by using microarrays. Methods and Findings Samples of uterine fundus, lower segment, and cervix were obtained from patients at term (mean +/- 6 SD = 39.1 +/- 0.5 wk) prior to the onset of labor (n = 6), or in active phase of labor with spontaneous onset (n = 7). Expression of 12,626 genes was evaluated using microarrays ( Human Genome U95A; Affymetrix) and compared between labor and non-labor samples. Genes with the largest labor-associated change and the lowest variability in expression are likely to be fundamental for parturition, so gene expression was ranked accordingly. From 500 genes with the highest rank we identified genes with similar expression profiles using two independent clustering techniques. Sets of genes with a probability of chance grouping by both techniques less than 0.01 represented 71.2%, 81.8%, and 79.8% of the 500 genes in the fundus, lower segment, and cervix, respectively. We identified 14, 14, and 12 those sets of genes in the fundus, lower segment, and cervix, respectively. This enabled networks of coregulated and co-expressed genes to be discovered. Many genes within the same cluster shared similar functions or had functions pertinent to the process of labor. Conclusions Our results provide support for many of the established processes of parturition and also describe novel-to-labor genes not previously associated with this process. The elucidation of these mechanisms likely to be fundamental for controlling labor is an important prerequisite to the development of effective treatments for major obstetric problems - including prematurity, with its long-term consequences to the health of mother and offspring

Progesterone-dependent induction of phospholipase C-related catalytically inactive protein 1 (PRIP-1) in decidualizing human endometrial stromal cells

Decidualization denotes the transformation of endometrial stromal cells into specialized decidual cells. In pregnancy, decidual cells form a protective matrix around the implanting embryo, enabling coordinated trophoblast invasion and formation of a functional placenta. Continuous progesterone (P4) signaling renders decidual cells resistant to various environmental stressors, whereas withdrawal inevitably triggers tissue breakdown and menstruation or miscarriage. Here, we show that PLCL1, coding phospholipase C (PLC)-related catalytically inactive protein 1 (PRIP-1), is highly induced in response to P4 signaling in decidualizing human endometrial stromal cells (HESCs). Knockdown experiments in undifferentiated HESCs revealed that PRIP-1 maintains basal phosphoinositide 3-kinase/Protein kinase B activity, which in turn prevents illicit nuclear translocation of the transcription factor forkhead box protein O1 and induction of the apoptotic activator BIM. By contrast, loss of this scaffold protein did not compromise survival of decidual cells. PRIP-1 knockdown did also not interfere with the responsiveness of HESCs to deciduogenic cues, although the overall expression of differentiation markers, such as PRL, IGFBP1, and WNT4, was blunted. Finally, we show that PRIP-1 in decidual cells uncouples PLC activation from intracellular Ca2+ release by attenuating inositol 1,4,5-trisphosphate signaling. In summary, PRIP-1 is a multifaceted P4-inducible scaffold protein that gates the activity of major signal transduction pathways in the endometrium. It prevents apoptosis of proliferating stromal cells and contributes to the relative autonomy of decidual cells by silencing PLC signaling downstream of Gq protein-coupled receptors

La construcción socioimaginaria de la protesta social en el discurso de la prensa latinoamericana: análisis de las editoriales de los diarios El Mercurio (Chile) y La Nación (Argentina) en el contexto de la crisis argentina de 2001

The present research work is proposed as a space for theoretical discussion and empirical analysis around the problematic of the power of the media in contexts of social conflict. Explicitly, this paper aims to analyze the socioimaginary construction of social protest in the editorial discourse produced by El Mercurio (Chile) and La Nación (Argentina) newspapers, based on the popular demonstrations that took place during December 2001 in the framework of the economic crisis in Argentina. To answer our research question and meet the goal of the study, we used a discourse analysis model that was applied to a corpus of 40 leading articles, selected from a sample of 80 journalistic texts published by El Mercurio and La Nación from December 1, 2001 to March 31, 2002. The main findings of the research regarding the mobilizations that took place in the context of the economic crisis in Argentina allow us to show that both newspapers built an imaginary of social protest that was based on a discourse with four categories: Civilization, barbarism, exclusion, and inclusion. Therefore, El Mercurio and La Nación newspapers not only made visible in the public space the events associated with the protests of December 2001, but also, these media channeled, through their leading articles, explanations about the conflict. They also participated in the public debate regarding collective protest actions, constructed representations and imaginary articulations about the events and social actors that participated in the interactions framed in the conflict, and, of course, assumed an ideological position in their quality of actors of the political system regarding the economic crisis and the social conflict that happened in the Argentine society during 2001.O presente trabalho de pesquisa propõe-se como um espaço para a discussão teórica e a análise empírica em torno da problemática do poder dos meios de comunicação em contextos de conflitividade social. De forma mais precisa, este artigo tem por finalidade analisar a construção socioimaginária do protesto social no discurso editorial produzido pelos jornais El Mercurio (Chile) e La Nación (Argentina) a partir das mobilizações populares que ocorreram durante dezembro de 2001 no âmbito da crise econômica na Argentina. Para responder a nossa pergunta de pesquisa e cumprir o objetivo do estudo, utilizou-se um modelo de análise do discurso que foi aplicado a um corpus de 40 editoriais selecionados a partir de uma amostra de 80 textos jornalísticos publicados pelos jornais El Mercurio e La Nación durante o período que vai do dia 1 dezembro de 2001 a 31 março de 2002. As principais descobertas da pesquisa obtidas a partir da análise dos editoriais publicados pelos jornais El Mercurio e La Nación com relação às mobilizações que ocorreram no contexto da crise econômica na Argentina, permitem-nos evidenciar que ambos os meios de comunicação construíram um imaginário do protesto social sobre a base de um discurso centrado em quatro categorias: civilização, barbárie, exclusão e inclusão. Portanto, os jornais El Mercurio e La Nación não apenas permitiram visibilizar no espaço público os acontecimentos associados aos protestos de dezembro de 2001, como também canalizaram, por meio de seus discursos editoriais, as explicações em torno do conflito, participaram do debate público com relação às ações coletivas de protesto, construíram representações e articularam imaginários sobre os acontecimentos e sobre os atores sociais que participaram das interações enquadradas no conflito, e que, desse modo, assumiram uma posição ideológica no papel de atores do sistema político com relação à crise econômica e o conflito social que se desenvolve na sociedade argentina durante 2001.El presente trabajo de investigación se propone como un espacio para la discusión teórica y EL análisis empírico en torno a la problemática del poder de los medios de comunicación en contextos de conflictividad social. De forma más precisa, este artículo tiene por finalidad analizar la construcción socioimaginaria de la protesta social en el discurso editorial producido por los diarios El Mercurio (Chile) y La Nación (Argentina) a partir de las movilizaciones populares que ocurrieron durante diciembre de 2001 en el marco de la crisis económica en Argentina. Para responder a nuestra pregunta de investigación y cumplir con el objetivo del estudio, se utilizó un modelo de análisis del discurso que fue aplicado a un corpus de 40 editoriales seleccionadas a partir de una muestra de 80 textos periodísticos publicados por los diarios El Mercurio y La Nación durante el periodo de tiempo que va desde el 1 diciembre de 2001 al 31 marzo de 2002. Los principales hallazgos de la investigación obtenidos a partir del análisis de las editoriales publicadas por los diarios El Mercurio y La Nación en relación a las movilizaciones que ocurrieron en el contexto de la crisis económica en Argentina, nos permiten evidenciar que ambos medios de comunicación construyeron un imaginario de la protesta social sobre la base de un discurso centrado en cuatro categorías: civilización, barbarie, exclusión e inclusión. Por consiguiente, los diarios El Mercurio y La Nación no solo permitieron visibilizar en el espacio público los acontecimientos asociados a las protestas de diciembre de 2001, sino que, además, estos medios canalizaron, a través de sus discursos editoriales, las explicaciones en torno al conflicto, participaron del debate público respecto a las acciones colectivas de protesta, construyeron representaciones y articularon imaginarios acerca de los sucesos y de los actores sociales que participaron de las interacciones enmarcadas en el conflicto, y, por supuesto, asumieron una posición ideológica en su calidad de actores del sistema político respecto a la crisis económica y el conflicto social que se desarrolla en la sociedad argentina durante el 2001.https://revistas.udem.edu.co/index.php/anagramas/article/view/206

Witt invariants of Weyl groups

We describe the Witt invariants of a Weyl group over a field $k_0$ by giving generators for the $W(k_0)$-module of Witt invariants, under certain assumptions on $k_0$ (which hold for any field of finite $2$-cohomological dimension). For the Weyl groups of types $B_n$, $C_n$, $D_n$, and $G_2$, we show that the Witt invariants are generated as a $W(k_0)$-algebra by trace forms and their exterior powers, extending a result due to Serre in type $A_n$. Many of our computational methods are applicable to computing Witt invariants of any smooth linear algebraic group over $k_0$, including a technique for lifting module generators from cohomological invariants to Witt invariants.Comment: 20 page