Equity Requires Action: Principals’ Use and Value of Culturally Proficient Educational Practice

This quantitative, descriptive study investigated K-12 public school principals\u27 perceptions regarding the degree to which they use and value practices related to cultural competence in their roles as school leaders. While an abundance of literature regarding leadership in education, disparities in educational outcomes, and school change exists, inequities in policy and practice perpetuate academic and social setbacks for some of our nation\u27s youth Using the lens of the Cultural Proficiency Framework, specifically the Essential Elements, this study aimed to address the research questions and add to the literature by examining (1) the school principals\u27 value in using culturally competent practices; (2) the school principals\u27 use of culturally competent practices; and (3) the differences in principals’ perceptions across urban, suburban, and rural locale. The study\u27s findings revealed the most important and most frequently used culturally competent practices to school principals were associated with valuing diversity. Conversely, the least important and least frequently used culturally competent practices to school principals were associated with assessing cultural knowledge. Conclusions suggest that applying the Essential Elements of Cultural Proficiency allows for paradigms shifts to praxis, where theory becomes practice through action towards equity and inclusion

Gyriosomus granulipennis Pizarro-Araya & Flores 2004 (Coleoptera: Tenebrionidae): An extreme case to preserve

El archipiélago de Los Choros, conformado por las islas Choros, Damas y Gaviota forma parte de la Reserva Nacional Pingüino de Humboldt y está situado dentro del desierto costero transicional de Chile (25º-32º S). Estudios recientes realizados en el archipiélago dan cuenta de una especie endémica de Tenebrionidae (Coleoptera) de la isla Choros (29º15’ S, 71º32’ O) descripta como Gyriosomus granulipennis Pizarro-Araya & Flores. El objetivo del presente trabajo es evaluar la prioridad de conservación de esta especie en el archipiélago mediante el análisis del Índice de Prioridad de Conservación (CPI), clasifi cación del Ministerio de Medio Ambiente (MMA) de Chile y lista roja de la IUCN. Nuestros resultados sostienen que esta especie puede ser catalogada en categoría En peligro por el índice CPI y Vulnerable según el MMA. Según criterios IUCN esta especie debería ser categorizada con Datos Defi cientes (DD), ya que muchos de los datos necesarios para la clasifi cación son difíciles de obtener para insectos o pueden sobrestimar o subestimar el riesgo de extinción de esta especie. Consideramos importante monitorear la continuidad de esta especie y conservarla a través del hábitat, para lo cual proponemos evitar el acceso a turistas y erradicar el conejo silvestre europeo.The Choros Archipelago includes three islands: Choros, Damas and Gaviota and it is part of The Pingüino de Humboldt National Reserve. These insular ecosystems are within the Chilean transitional coastal (25º-32º S). Prior researches in the archipelago reported a species of Tenebrionidae (Coleoptera) endemic to Choros island (29º15’ S, 71º32’ W) described as Gyriosomus granulipennis Pizarro-Araya & Flores. The objective of this paper is to evaluate the vulnerability of this species in the archipelago through Conservation Priority Index (CPI), Environmental Ministery of Chile (MMA) and Red List of IUCN. We concluded that G. granulipennis is Endangered by CPI index, and Vulnerable by MMA of Chile. Additionally, this species can be classiffi ed with Defi cient Data (DD) by IUCN because many of data are impossible or diffi cult to obtain for insects and can overestimate or underestimate the risk of extinction of this species. We consider important to monitoring the continuity of this species and the protection of habitat, for which we propose not allow access the tourists and eradication of European rabbit.Fil: Pizarro Ayala, Jaime. Universidad de La Serena; ChileFil: Flores, Gustavo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Vergara, Olivia E.. Universidad de Concepción; Chil

Self-Healing Polymer Nanocomposite Materials by Joule Effect

Nowadays, the self-healing approach in materials science mainly relies on functionalized polymers used as matrices in nanocomposites. Through different physicochemical pathways and stimuli, these materials can undergo self-repairing mechanisms that represent a great advantage to prolonging materials service-life, thus avoiding early disposal. Particularly, the use of the Joule effect as an external stimulus for self-healing in conductive nanocomposites is under-reported in the literature. However, it is of particular importance because it incorporates nanofillers with tunable features thus producing multifunctional materials. The aim of this review is the comprehensive analysis of conductive polymer nanocomposites presenting reversible dynamic bonds and their energetical activation to perform self-healing through the Joule effect

Metal solution precursors: their role during the synthesis of MoVTeNb mixed oxide catalysts

[EN] Synthesized via the slurry method and activated at high temperature (873 K), MoVTeNb multimetallic mixed oxides are applied to catalyze the oxidative dehydrogenation of ethane to ethylene (ODHE). Mixed oxides typically contain M1 and M2 crystalline phases, the relative contribution of these phases and the respective catalytic behaviour being notably influenced by the preparation conditions of the metallic aqueous solution precursor, given the complexity of the chemical interactions of metal species in solution. Thus, detailed in situ UV-vis and Raman studies of the chemical species formed in solution during each step of the synthetic procedure are presented herein. The main role of vanadium is to form decavanadate ions, which interact with Mo species to generate an Anderson-type structure. When niobium oxalate solution is added into the MoVTe solution, a yellow-coloured gel is immediately formed due to a common ion effect. When liquid and gel phases are separated, the M1 crystalline phase is produced solely from the gel phase. Attention is also devoted to the influence and role of each metal cation (Mo, V, Te and Nb) on the formation of the active M1 crystalline phase and the catalytic behaviour in the ODHE. The catalyst constituted mostly of M1 crystalline phase is able to convert 45% of the fed ethane, with a selectivity to ethylene of around 90%.This work was financially supported by the Instituto Mexicano del Petroleo (IMP) Project D.61010. EMF thanks CONACyT Mexico and IMP. JMLN thanks DGICYT in Spain (Project CTQ2015-68951-C3-1-R).Sánchez-Valente, J.; Maya-Flores, E.; Armendariz-Herrera, H.; Quintana-Solorzano, R.; López Nieto, JM. (2018). Metal solution precursors: their role during the synthesis of MoVTeNb mixed oxide catalysts. Catalysis Science & Technology. 8(12):3123-3132. https://doi.org/10.1039/c8cy00750kS31233132812Ushikubo, T., Oshima, K., Kayou, A., Vaarkamp, M., & Hatano, M. (1997). Ammoxidation of Propane over Catalysts Comprising Mixed Oxides of Mo and V. Journal of Catalysis, 169(1), 394-396. doi:10.1006/jcat.1997.1692Ushikubo, T., Oshima, K., Kayou, A., & Hatano, M. (1997). Ammoxidation of propane over Mo-V-Nb-Te mixed oxide catalysts. Spillover and Migration of Surface Species on Catalysts, Proceedings of the 4th International Conference on Spillover, 473-480. doi:10.1016/s0167-2991(97)80871-3Ushikubo, T. (2000). Recent topics of research and development of catalysis by niobium and tantalum oxides. Catalysis Today, 57(3-4), 331-338. doi:10.1016/s0920-5861(99)00344-2Ueda, W., & Oshihara, K. (2000). Selective oxidation of light alkanes over hydrothermally synthesized Mo-V-M-O (M=Al, Ga, Bi, Sb, and Te) oxide catalysts. Applied Catalysis A: General, 200(1-2), 135-143. doi:10.1016/s0926-860x(00)00627-xWatanabe, H., & Koyasu, Y. (2000). New synthesis route for Mo–V–Nb–Te mixed oxides catalyst for propane ammoxidation. Applied Catalysis A: General, 194-195, 479-485. doi:10.1016/s0926-860x(99)00394-4Botella, P., Solsona, B., Martinez-Arias, A., & López Nieto, J. M. (2001). Catalysis Letters, 74(3/4), 149-154. doi:10.1023/a:1016614132694Oshihara, K., Hisano, T., & Ueda, W. (2001). Topics in Catalysis, 15(2/4), 153-160. doi:10.1023/a:1016630307377Botella, P., López Nieto, J. M., Solsona, B., Mifsud, A., & Márquez, F. (2002). The Preparation, Characterization, and Catalytic Behavior of MoVTeNbO Catalysts Prepared by Hydrothermal Synthesis. Journal of Catalysis, 209(2), 445-455. doi:10.1006/jcat.2002.3648Millet, J. M. M., Roussel, H., Pigamo, A., Dubois, J. L., & Jumas, J. C. (2002). Characterization of tellurium in MoVTeNbO catalysts for propane oxidation or ammoxidation. Applied Catalysis A: General, 232(1-2), 77-92. doi:10.1016/s0926-860x(02)00078-9DeSanto Jr., P., Buttrey, D. J., Grasselli, R. K., Lugmair, C. G., Volpe, A. F., Toby, B. H., & Vogt, T. (2003). Topics in Catalysis, 23(1/4), 23-38. doi:10.1023/a:1024812101856Millet, J. M. ., Baca, M., Pigamo, A., Vitry, D., Ueda, W., & Dubois, J. . (2003). Study of the valence state and coordination of antimony in MoVSbO catalysts determined by XANES and EXAFS. Applied Catalysis A: General, 244(2), 359-370. doi:10.1016/s0926-860x(02)00614-2BOTELLA, P. (2004). Selective oxidative dehydrogenation of ethane on MoVTeNbO mixed metal oxide catalysts. Journal of Catalysis, 225(2), 428-438. doi:10.1016/j.jcat.2004.04.024Holmberg, J., Grasselli, R. K., & Andersson, A. (2004). Catalytic behaviour of M1, M2, and M1/M2 physical mixtures of the Mo–V–Nb–Te–oxide system in propane and propene ammoxidation. Applied Catalysis A: General, 270(1-2), 121-134. doi:10.1016/j.apcata.2004.04.029Grasselli, R. K., Buttrey, D. J., DeSanto, P., Burrington, J. D., Lugmair, C. G., Volpe, A. F., & Weingand, T. (2004). Active centers in Mo–V–Nb–Te–O (amm)oxidation catalysts. Catalysis Today, 91-92, 251-258. doi:10.1016/j.cattod.2004.03.060Ueda, W., Vitry, D., & Katou, T. (2005). Crystalline MoVO based complex oxides as selective oxidation catalysts of propane. Catalysis Today, 99(1-2), 43-49. doi:10.1016/j.cattod.2004.09.022Murayama, H., Vitry, D., Ueda, W., Fuchs, G., Anne, M., & Dubois, J. L. (2007). Structure characterization of orthorhombic phase in MoVTeNbO catalyst by powder X-ray diffraction and XANES. Applied Catalysis A: General, 318, 137-142. doi:10.1016/j.apcata.2006.10.050Guliants, V. V., Bhandari, R., Swaminathan, B., Vasudevan, V. K., Brongersma, H. H., Knoester, A., … Han, S. (2005). Roles of Surface Te, Nb, and Sb Oxides in Propane Oxidation to Acrylic Acid over Bulk Orthorhombic Mo−V−O Phase. The Journal of Physical Chemistry B, 109(50), 24046-24055. doi:10.1021/jp054641yGrasselli, R. K., Buttrey, D. J., Burrington, J. D., Andersson, A., Holmberg, J., Ueda, W., … Volpe, A. F. (2006). Active centers, catalytic behavior, symbiosis and redox properties of MoV(Nb,Ta)TeO ammoxidation catalysts. Topics in Catalysis, 38(1-3), 7-16. doi:10.1007/s11244-006-0066-xSafonova, O. V., Deniau, B., & Millet, J.-M. M. (2006). Mechanism of the Oxidation−Reduction of the MoVSbNbO Catalyst:  In Operando X-ray Absorption Spectroscopy and Electrical Conductivity Measurements. The Journal of Physical Chemistry B, 110(47), 23962-23967. doi:10.1021/jp064347lWagner, J. B., Timpe, O., Hamid, F. A., Trunschke, A., Wild, U., Su, D. S., … Schlögl, R. (2006). Surface texturing of Mo–V–Te–Nb–O x selective oxidation catalysts. Topics in Catalysis, 38(1-3), 51-58. doi:10.1007/s11244-006-0070-1Kolen’ko, Y. V., Zhang, W., d’ Alnoncourt, R. N., Girgsdies, F., Hansen, T. W., Wolfram, T., … Trunschke, A. (2011). Synthesis of MoVTeNb Oxide Catalysts with Tunable Particle Dimensions. ChemCatChem, 3(10), 1597-1606. doi:10.1002/cctc.201100089Hävecker, M., Wrabetz, S., Kröhnert, J., Csepei, L.-I., Naumann d’Alnoncourt, R., Kolen’ko, Y. V., … Trunschke, A. (2012). Surface chemistry of phase-pure M1 MoVTeNb oxide during operation in selective oxidation of propane to acrylic acid. Journal of Catalysis, 285(1), 48-60. doi:10.1016/j.jcat.2011.09.012Ishikawa, S., Tashiro, M., Murayama, T., & Ueda, W. (2014). Seed-Assisted Synthesis of Crystalline Mo3VOx Oxides and Their Crystal Formation Mechanism. Crystal Growth & Design, 14(9), 4553-4561. doi:10.1021/cg500661pNieto, J. M. L., Botella, P., Vázquez, M. I., & Dejoz, A. (2002). The selective oxidative dehydrogenation of ethane over hydrothermally synthesised MoVTeNb catalysts. Chem. Commun., (17), 1906-1907. doi:10.1039/b204037aLópez Nieto, J. ., Botella, P., Concepción, P., Dejoz, A., & Vázquez, M. . (2004). Oxidative dehydrogenation of ethane on Te-containing MoVNbO catalysts. Catalysis Today, 91-92, 241-245. doi:10.1016/j.cattod.2004.03.040Ivars, F., Botella, P., Dejoz, A., Nieto, J. M. L., Concepción, P., & Vázquez, M. I. (2006). Selective oxidation of short-chain alkanes over hydrothermally prepared MoVTeNbO catalysts. Topics in Catalysis, 38(1-3), 59-67. doi:10.1007/s11244-006-0071-0Botella, P., Dejoz, A., Abello, M. C., Vázquez, M. I., Arrúa, L., & López Nieto, J. M. (2009). Selective oxidation of ethane: Developing an orthorhombic phase in Mo–V–X (X=Nb, Sb, Te) mixed oxides. Catalysis Today, 142(3-4), 272-277. doi:10.1016/j.cattod.2008.09.016Deniau, B., Millet, J. M. M., Loridant, S., Christin, N., & Dubois, J. L. (2008). Effect of several cationic substitutions in the M1 active phase of the MoVTeNbO catalysts used for the oxidation of propane to acrylic acid. Journal of Catalysis, 260(1), 30-36. doi:10.1016/j.jcat.2008.08.020SOLSONA, B., VAZQUEZ, M., IVARS, F., DEJOZ, A., CONCEPCION, P., & LOPEZNIETO, J. (2007). Selective oxidation of propane and ethane on diluted Mo–V–Nb–Te mixed-oxide catalysts. Journal of Catalysis, 252(2), 271-280. doi:10.1016/j.jcat.2007.09.019Nguyen, T. T., Burel, L., Nguyen, D. L., Pham-Huu, C., & Millet, J. M. M. (2012). Catalytic performance of MoVTeNbO catalyst supported on SiC foam in oxidative dehydrogenation of ethane and ammoxidation of propane. Applied Catalysis A: General, 433-434, 41-48. doi:10.1016/j.apcata.2012.04.038Nguyen, T. T., Aouine, M., & Millet, J. M. M. (2012). Optimizing the efficiency of MoVTeNbO catalysts for ethane oxidative dehydrogenation to ethylene. Catalysis Communications, 21, 22-26. doi:10.1016/j.catcom.2012.01.026Valente, J. S., Armendáriz-Herrera, H., Quintana-Solórzano, R., del Ángel, P., Nava, N., Massó, A., & López Nieto, J. M. (2014). Chemical, Structural, and Morphological Changes of a MoVTeNb Catalyst during Oxidative Dehydrogenation of Ethane. ACS Catalysis, 4(5), 1292-1301. doi:10.1021/cs500143jTHORSTEINSON, E. (1978). The oxidative dehydrogenation of ethane over catalysts containing mixed oxides of molybdenum and vanadium. Journal of Catalysis, 52(1), 116-132. doi:10.1016/0021-9517(78)90128-8Ishikawa, S., Yi, X., Murayama, T., & Ueda, W. (2014). Heptagonal channel micropore of orthorhombic Mo3VOx as catalysis field for the selective oxidation of ethane. Applied Catalysis A: General, 474, 10-17. doi:10.1016/j.apcata.2013.07.050Ishikawa, S., Yi, X., Murayama, T., & Ueda, W. (2014). Catalysis field in orthorhombic Mo3VOx oxide catalyst for the selective oxidation of ethane, propane and acrolein. Catalysis Today, 238, 35-40. doi:10.1016/j.cattod.2013.12.054Grasselli, R. K., Burrington, J. D., Buttrey, D. J., DeSanto Jr., P., Lugmair, C. G., Volpe Jr., A. F., & Weingand, T. (2003). Topics in Catalysis, 23(1/4), 5-22. doi:10.1023/a:1024859917786Grasselli, R. K., Lugmair, C. G., Volpe Jr., A. F., Andersson, A., & Burrington, J. D. (2010). Enhancement of acrylic acid yields in propane and propylene oxidation by selective P Doping of MoV(Nb)TeO-based M1 and M2 catalysts. Catalysis Today, 157(1-4), 33-38. doi:10.1016/j.cattod.2010.01.044Grasselli, R. K., Lugmair, C. G., & Volpe, A. F. (2011). Towards an Understanding of the Reaction Pathways in Propane Ammoxidation Based on the Distribution of Elements at the Active Centers of the M1 Phase of the MoV(Nb,Ta)TeO System. Topics in Catalysis, 54(10-12), 595-604. doi:10.1007/s11244-011-9681-2Grasselli, R. K. (2014). Site isolation and phase cooperation: Two important concepts in selective oxidation catalysis: A retrospective. Catalysis Today, 238, 10-27. doi:10.1016/j.cattod.2014.05.036Ramli, I., Botella, P., Ivars, F., Pei Meng, W., Zawawi, S. M. M., Ahangar, H. A., … Nieto, J. M. L. (2011). Reflux method as a novel route for the synthesis of MoVTeNbOx catalysts for selective oxidation of propane to acrylic acid. Journal of Molecular Catalysis A: Chemical, 342-343, 50-57. doi:10.1016/j.molcata.2011.04.009Naraschewski, F. N., Praveen Kumar, C., Jentys, A., & Lercher, J. A. (2011). Phase formation and selective oxidation of propane over MoVTeNbOx catalysts with varying compositions. Applied Catalysis A: General, 391(1-2), 63-69. doi:10.1016/j.apcata.2010.07.005Blasco, T., Botella, P., Concepción, P., López Nieto, J. M., Martinez-Arias, A., & Prieto, C. (2004). Selective oxidation of propane to acrylic acid on K-doped MoVSbO catalysts: catalyst characterization and catalytic performance. Journal of Catalysis, 228(2), 362-373. doi:10.1016/j.jcat.2004.08.036YANG, X., FENG, R., JI, W., & AU, C. (2008). Characterization and evaluation of MoVTeNb mixed metal oxide catalysts fabricated via hydrothermal process with ultrasonic pretreatment for propane partial oxidation. Journal of Catalysis, 253(1), 57-65. doi:10.1016/j.jcat.2007.10.020GAFFNEY, A., CHATURVEDI, S., CLARKJR, M., HAN, S., LE, D., RYKOV, S., & CHEN, J. (2005). Characterization and catalytic studies of PVD synthesized Mo/V/Nb/Te oxide catalysts. Journal of Catalysis, 229(1), 12-23. doi:10.1016/j.jcat.2004.09.013Espinal, L., Malinger, K. A., Espinal, A. E., Gaffney, A. M., & Suib, S. L. (2007). Preparation of Multicomponent Metal Oxides Using Nozzle Spray and Microwaves. Advanced Functional Materials, 17(14), 2572-2579. doi:10.1002/adfm.200600744Kolen’ko, Y. V., Amakawa, K., d’ Alnoncourt, R. N., Girgsdies, F., Weinberg, G., Schlögl, R., & Trunschke, A. (2012). Unusual Phase Evolution in MoVTeNb Oxide Catalysts Prepared by a Novel Acrylamide-Gelation Route. ChemCatChem, 4(4), 495-503. doi:10.1002/cctc.201100451Concepción, P., Hernández, S., & Nieto, J. M. L. (2011). On the nature of active sites in MoVTeO and MoVTeNbO catalysts: The influence of catalyst activation temperature. Applied Catalysis A: General, 391(1-2), 92-101. doi:10.1016/j.apcata.2010.05.011Botella, P., García-González, E., López Nieto, J. M., & González-Calbet, J. M. (2005). MoVTeNbO multifunctional catalysts: Correlation between constituent crystalline phases and catalytic performance. Solid State Sciences, 7(5), 507-519. doi:10.1016/j.solidstatesciences.2005.01.012Beato, P., Blume, A., Girgsdies, F., Jentoft, R. E., Schlögl, R., Timpe, O., … Mohd Salim, L. (2006). Analysis of structural transformations during the synthesis of a MoVTeNb mixed oxide catalyst. Applied Catalysis A: General, 307(1), 137-147. doi:10.1016/j.apcata.2006.03.014Celaya Sanfiz, A., Hansen, T. W., Girgsdies, F., Timpe, O., Rödel, E., Ressler, T., … Schlögl, R. (2008). Preparation of Phase-Pure M1 MoVTeNb Oxide Catalysts by Hydrothermal Synthesis—Influence of Reaction Parameters on Structure and Morphology. Topics in Catalysis, 50(1-4), 19-32. doi:10.1007/s11244-008-9106-zOzeki, T., Kihara, H., & Ikeda, S. (1988). 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E.Mesmer , in The Hydrolysis of Cations , Wiley N.Y. , 1970Tsuji, H., & Koyasu, Y. (2002). Synthesis of MoVNbTe(Sb)OxComposite Oxide Catalysts via Reduction of Polyoxometalates in an Aqueous Medium. Journal of the American Chemical Society, 124(20), 5608-5609. doi:10.1021/ja0122344Maksimovskaya, R. I., Bondareva, V. M., & Aleshina, G. I. (2008). NMR Spectroscopic Studies of Interactions in Solution during the Synthesis of MoVTeNb Oxide Catalysts. European Journal of Inorganic Chemistry, 2008(31), 4906-4914. doi:10.1002/ejic.200800500Griffith, W. P., & Lesniak, P. J. B. (1969). Raman studies on species in aqueous solutions. Part III. Vanadates, molybdates, and tungstates. Journal of the Chemical Society A: Inorganic, Physical, Theoretical, 1066. doi:10.1039/j19690001066Butler, I. S., El-Sherbeny, H. A. M., Kenawy, I. M., & Mostafa, S. I. (2013). 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Cell dedifferentiation and epithelial to mesenchymal transitions during intestinal regeneration in H. glaberrima

<p>Abstract</p> <p>Background</p> <p>Determining the type and source of cells involved in regenerative processes has been one of the most important goals of researchers in the field of regeneration biology. We have previously used several cellular markers to characterize the cells involved in the regeneration of the intestine in the sea cucumber <it>Holothuria glaberrima</it>.</p> <p>Results</p> <p>We have now obtained a monoclonal antibody that labels the mesothelium; the outer layer of the gut wall composed of peritoneocytes and myocytes. Using this antibody we studied the role of this tissue layer in the early stages of intestinal regeneration. We have now shown that the mesothelial cells of the mesentery, specifically the muscle component, undergo dedifferentiation from very early on in the regeneration process. Cell proliferation, on the other hand, increases much later, and mainly takes place in the mesothelium or coelomic epithelium of the regenerating intestinal rudiment. Moreover, we have found that the formation of the intestinal rudiment involves a novel regenerative mechanism where epithelial cells ingress into the connective tissue and acquire mesenchymal phenotypes.</p> <p>Conclusions</p> <p>Our results strongly suggest that the dedifferentiating mesothelium provides the initial source of cells for the formation of the intestinal rudiment. At later stages, cell proliferation supplies additional cells necessary for the increase in size of the regenerate. Our data also shows that the mechanism of epithelial to mesenchymal transition provides many of the connective tissue cells found in the regenerating intestine. These results present some new and important information as to the cellular basis of organ regeneration and in particular to the process of regeneration of visceral organs.</p

The rapid atmospheric monitoring system of the Pierre Auger Observatory

The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 10^17 eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by optical telescopes at the Observatory. To correct the observations for variations in atmospheric conditions, atmospheric monitoring is performed at regular intervals ranging from several minutes (for cloud identification) to several hours (for aerosol conditions) to several days (for vertical profiles of temperature, pressure, and humidity). In 2009, the monitoring program was upgraded to allow for additional targeted measurements of atmospheric conditions shortly after the detection of air showers of special interest, e. g., showers produced by very high-energy cosmic rays or showers with atypical longitudinal profiles. The former events are of particular importance for the determination of the energy scale of the Observatory, and the latter are characteristic of unusual air shower physics or exotic primary particle types. The purpose of targeted (or "rapid") monitoring is to improve the resolution of the atmospheric measurements for such events. In this paper, we report on the implementation of the rapid monitoring program and its current status. The rapid monitoring data have been analyzed and applied to the reconstruction of air showers of high interest, and indicate that the air fluorescence measurements affected by clouds and aerosols are effectively corrected using measurements from the regular atmospheric monitoring program. We find that the rapid monitoring program has potential for supporting dedicated physics analyses beyond the standard event reconstruction

A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory

Observations of cosmic rays arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three method can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ... , 110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays

Antennas for the detection of radio emission pulses from cosmic-ray induced air showers at the Pierre Auger Observatory.

The Pierre Auger Observatory is exploring the potential of the radio detection technique to study extensive air showers induced by ultra-high energy cosmic rays. The Auger Engineering Radio Array (AERA) addresses both technological and scientific aspects of the radio technique. A first phase of AERA has been operating since September 2010 with detector stations observing radio signals at frequencies between 30 and 80 MHz. In this paper we present comparative studies to identify and optimize the antenna design for the final configuration of AERA consisting of 160 individual radio detector stations. The transient nature of the air shower signal requires a detailed description of the antenna sensor. As the ultra-wideband reception of pulses is not widely discussed in antenna literature, we review the relevant antenna characteristics and enhance theoretical considerations towards the impulse response of antennas including polarization effects and multiple signal reflections. On the basis of the vector effective length we study the transient response characteristics of three candidate antennas in the time domain. Observing the variation of the continuous galactic background intensity we rank the antennas with respect to the noise level added to the galactic signal

A search for point sources of EeV neutrons

A thorough search of the sky exposed at the Pierre Auger Cosmic Ray Observatory reveals no statistically significant excess of events in any small solid angle that would be indicative of a flux of neutral particles from a discrete source. The search covers from -90 degrees to +15 degrees in declination using four different energy ranges above 1 EeV (10(18) eV). The method used in this search is more sensitive to neutrons than to photons. The upper limit on a neutron flux is derived for a dense grid of directions for each of the four energy ranges. These results constrain scenarios for the production of ultrahigh energy cosmic rays in the Galaxy

Search for point-like sources of ultra-high energy neutrinos at the pierre auger observatory and improved limit on the diffuse flux of tau neutrinos

The surface detector array of the Pierre Auger Observatory can detect neutrinos with energy E_ν between 10^17 eV and 10^20 eV from point-like sources across the sky south of +55 degrees and north of -65 degrees declinations. A search has been performed for highly inclined extensive air showers produced by the interaction of neutrinos of all flavors in the atmosphere (downward-going neutrinos), and by the decay of tau leptons originating from tau neutrino interactions in Earth's crust (Earth-skimming neutrinos). No candidate neutrinos have been found in data up to 2010 May 31. This corresponds to an equivalent exposure of ∼3.5 years of a full surface detector array for the Earth-skimming channel and ∼2 years for the downward-going channel. An improved upper limit on the diffuse flux of tau neutrinos has been derived. Upper limits on the neutrino flux from point-like sources have been derived as a function of the source declination. Assuming a differential neutrino flux k_PS . E_nu^-2. from a point-like source, 90% confidence level upper limits for k_PS at the level of ≈5x10^-7 and 2.5x10^-6 GeV cm^-2 s^-1 have been obtained over a broad range of declinations from the searches for Earth-skimming and downward-going neutrinos, respectively