2,179 research outputs found

    Traces of Time: Urban Palimpsest and Transformations

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    I contend that the city is a deeply scored palimpsest that through specific natural, social, and cultural changes reveals its traces of permanence and temporality; therefore, to create in the urban realm is to respond to these vestiges of time through decoding and transformation, as if one was gently manipulating the genome of the city

    Status report of the baseline collimation system of CLIC. Part II

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    Important efforts have recently been dedicated to the characterisation and improvement of the design of the post-linac collimation system of the Compact Linear Collider (CLIC). This system consists of two sections: one dedicated to the collimation of off-energy particles and another one for betatron collimation. The energy collimation system is further conceived as protection system against damage by errant beams. In this respect, special attention is paid to the optimisation of the energy collimator design. The material and the physical parameters of the energy collimators are selected to withstand the impact of an entire bunch train. Concerning the betatron collimation section, different aspects of the design have been optimised: the transverse collimation depths have been recalculated in order to reduce the collimator wakefield effects while maintaining a good efficiency in cleaning the undesired beam halo; the geometric design of the spoilers has been reviewed to minimise wakefields; in addition, the optics design has been optimised to improve the collimation efficiency. This report presents the current status of the the post-linac collimation system of CLIC. Part II is mainly dedicated to the study of the betatron collimation system and collimator wakefield effects.Comment: 25 pages, 13 figure

    Usefulness of multimodal MR imaging in the differential diagnosis of HaNDL and acute ischemic stroke

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    <p>Abstract</p> <p>Background</p> <p>Syndrome of transient Headache and Neurological Deficits with cerebrospinal fluid Lymphocitosis (HaNDL) is a rare disease which can present with focal neurological deficits and mimic stroke. A neurologist-on-duty faced with a HaNDL patient in the first hours might erroneously decide to use thrombolytic drugs, a non-innocuous treatment which has no therapeutic effect on this syndrome.</p> <p>Case Presentation</p> <p>We present a case where neuroimaging, together with the clinical picture, led to a presumed diagnosis of HaNDL avoiding intravenous thrombolysis.</p> <p>Conclusions</p> <p>This report shows the usefulness of multimodal MR imaging in achieving early diagnosis during an acute neurological attack of HaNDL. Our experience, along with that of others, demonstrates that neuroimaging tests reveal the presence of cerebral hypoperfusion in HaNDL syndrome</p

    Progress in creating a joint research agenda that allows networked long-term socio-ecological research in southern South America : addressing crucial technological and human capacity gaps limiting its application in Chile and Argentina

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    Since 1980, more than 40 countries have implemented long-term ecological research (LTER) programs, which have shown their power to affect advances in basic science to understand the natural world at meaningful temporal and spatial scales and also help link research with socially relevant outcomes. Recently, a disciplinary paradigmatic shift has integrated the human dimensions of ecosystems, leading to a long-term socio-ecological research (LTSER) framework to address the world's current environmental challenges. A global gap in LTER/LTSER only exists in the latitudinal range of 40–60°S, corresponding to Argentina and Chile's temperate/sub-Antarctic biome. A team of Chilean, Argentine and US researchers has participated in an ongoing dialogue to define not only conceptual, but also practical barriers limiting LTER/LTSER in southern South America. We have found a number of existing long-term research sites and platforms throughout the region, but at the same time it has been concluded an agenda is needed to create and implement further training courses for students, postdoctoral fellows and young scientists, particularly in the areas of data and information management systems. Since LTER/LTSER efforts in Chile and Argentina are incipient, instituting such courses now will enhance human and technical capacity of the natural science and resource community to improve the collection, storage, analysis and dissemination of information in emerging LTER/LTSER platforms. In turn, having this capacity, as well as the ongoing formalization of LTER/LTSER programs at national levels, will allow the enhancement of crucial collaborations and comparisons between long-term research programs within the region and between hemispheres and continents. For Spanish version of the entire article, see Online Supporting Information (Appendix S1).Desde 1980, más de cuarenta países han implementado programas de Investigación Ecológica a Largo Plazo (LTER por sus siglas en inglés), los cuales han mostrado su capacidad para influir sobre los avances en las ciencias básicas que permiten entender el mundo natural en escalas temporales y espaciales significativas, y también ayudar a enfocar la investigación hacia estudios socialmente relevantes. Recientemente, gracias a un cambio de paradigma en la disciplina, se integró también la dimensión humana de los ecosistemas, llevándola a un marco conceptual de Investigación Socio-Ecológica a Largo Plazo (LTSER por sus siglas en inglés) para enfrentar los desafíos medio-ambientales del mundo actual. Existe un vacío global en LTER/LTSER en el rango latitudinal de 40–60°S, correspondiente a los biomas templados/subantárticos de Argentina y Chile. Un equipo de investigadores chilenos, argentinos y estadounidenses ha trabajado por varios años para definir cuáles son la barreras que actualmente limitan la creación de una Red de LTER/LTSER en el sur de Sudamérica, no solamente en términos conceptuales, sino también a nivel práctico. Existe un buen número de sitios de investigación a largo plazo en la región, pero también concluimos que es necesario crear e implementar más cursos de capacitación para estudiantes, investigadores post-doctorales y jóvenes científicos, particularmente en las áreas de sistemas de manejo de datos e información. Considerando que los esfuerzos LTER/LTSER en Chile y Argentina son incipientes, este tipo de cursos podría mejorar la capacidad humana y técnica en la comunidad de las ciencias y los recursos naturales, así como mejorar los procesos de recolección, almacenamiento, análisis y difusión de la información. A su vez, la formalización de cursos de programas LTER/LTSER a nivel nacional para adquirir dicha capacidad de manejo de la información, permitirá un fortalecimiento crucial de las colaboraciones y comparaciones entre programas de investigación a largo plazo dentro de la región, y entre hemisferios y continentes. La versión en castellano del artículo se encuentra disponible en forma digital como Online Supporting Information S1.Fil: Anderson, Chistopher B. University of North Texas. Department of Biological Sciences; Estados UnidosFil: Celis-Diez, Juan Luis. Pontificia Universidad Católica de Valparaíso, Escuela de Agronomía; ChileFil: Bond, Barbara J.H.G. Oregon State University. Andrews Forest Long-Term Ecological Research Site. Department of Forest Ecosystems and Society; Estados UnidosFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Cientificas; ArgentinaFil: Little, Christian. Universidad Austral de Chile. Facultad de Ciencias. Instituto de Ciencias de la Tierra y Evolución; Chile. Fundación Centro de los Bosques Nativos FORECOS; ChileFil: Armesto, Juan J. Pontificia Universidad Católica de Valparaíso, Escuela de Agronomía; ChileFil: Ghersa, Claudio Marco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Austin, Amy Theresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Schlichter, Tomas Miguel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Grupo de Ecología Forestal; ArgentinaFil: Lara, Antonio. Fundación Centro de los Bosques Nativos FORECOS; Chile. Universidad Austral de Chile. Facultad de Ciencias Forestales y Recursos Naturales. Instituto de Silvicultura; ChileFil: Carmona, Martin. Universidad de Chile. Instituto de Ecologıa y Biodiversidad; ChileFil: Chaneton, Enrique Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Recursos Naturales y Ambiente; ArgentinaFil: Gutierrez, Julio R. Universidad de La Serena. Departamento de Biología. Instituto de Ecología y Biodiversidad. Centro de Estudios Avanzados en Zonas Aridas; ChileFil: Rozzi, Ricardo. Universidad de La Serena. Departamento de Biología. Instituto de Ecología y Biodiversidad; ChileFil: Vanderbilt, Kristin University of New Mexico. Department of Biology. Sevilleta Long-Term Ecological Research Site; Estados UnidosFil: Oyarce, Guillermo University of North Texas. Library and Information Sciences; Estados UnidosFil: Fernandez, Roberto J. University of North Texas, Department of Biological Sciences; Estados Unido

    Regulation of membrane ruffling by polarized STIM1 and ORAI1in cortactin-rich domains

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    La movilidad celular y la migración requieren la reorganización del citoesqueleto cortical en el borde principal de las células y la entrada de Ca2 + extracelular es esencial para esta reorganización. Sin embargo, la naturaleza molecular de los reguladores de esta vía es desconocida. Este trabajo contribuye a comprender el papel de STIM1 y ORAI1 en la promoción de la ondulación de la membrana al mostrar que la fosfo-STIM1 se localiza en el borde principal de las células, y que tanto phospho-STIM1 como ORAI1 se localizan conjuntamente con la cortactina (CTTN), un regulador del citoesqueleto en las zonas de rizo de la membrana. Las líneas celulares STIM1-KO y ORAI1-KO se generaron mediante la edición del genoma CRISPR / Cas9 en células U2OS. En ambos casos, las células KO presentaron una reducción notable de la entrada de Ca2 + operada por el almacén (SOCE) que se rescató mediante la expresión de STIM1-mCherry y ORAI1-mCherry. Estos resultados demostraron que SOCE regula la deformación de la membrana en el borde anterior de las células. Por otra parte, ORAI1 endógeno y ORAI1-GFP sobreexpresado coinmuno precipitado con CTTN endógeno. Este último resultado, además del fenotipo de las células KO, la preservación de la co-localización de ORAI1-CTTN durante el fruncido, y la inhibición de la rizo de la membrana por parte del inhibidor del canal de Ca2 + SKF96365, apoya aún más un vínculo funcional entre el SOCE y el fruncido de la membrana.Cell motility and migration requires the reorganization of the cortical cytoskeleton at the leading edge of cells and extracellular Ca2+ entry is essential for this reorganization. However the molecular nature of the regulators of this pathway is unknown. This work contributes to understanding the role of STIM1 and ORAI1 in the promotion of membrane ruffling by showing that phospho-STIM1 localizes at the leading edge of cells, and that both phospho-STIM1 and ORAI1 co-localize with cortactin (CTTN), a regulator of the cytoskeleton at membrane ruffling areas. STIM1-KO and ORAI1-KO cell lines were generated by CRISPR/Cas9 genome editing in U2OS cells. In both cases, KO cells presented a notable reduction of store-operated Ca2+ entry (SOCE) that was rescued by expression of STIM1-mCherry and ORAI1-mCherry. These results demonstrated that SOCE regulates membrane ruffling at the leading edge of cells. Moreover, endogenous ORAI1 and overexpressed ORAI1-GFP co-immuno precipitated with endogenous CTTN. This latter result, in addition to the KO cells’ phenotype, the preservation of ORAI1-CTTN co-localization during ruffling, and the inhibition of membrane ruffling g by the Ca2+- channel inhibitor SKF96365, further supports a functional link between SOCE and membrane ruffling.• Ministerio de Economía y Competitividad y Fondo Social Europeo. Becas BFU2011-22798 y BFU2014-52401-P, para Francisco Javier Martín Romero • Consejo de Investigación Médica. Beca MC_UU_12016 / 2, para Darío R. Alessi • Ministerio de Economía y Competitividad. Beca BES-2012-052061, para Aida María López Guerrero • Gobierno de Extremadura. Ayuda PD10081, para Patricia Tomás Martín • Ministerio de Educación, Cultura y Deporte. Beca FPU13 / 03430, para Carlos Pascual Caro • Consejo de Investigación Médica. Ayuda MR / K015869 / 1, para Graeme Ball • EMBO. Beca ASTF-311-2014, para Eulalia Pozo Guisado • Ministerio de Educación, Cultura Española y Deporte. Beca PRX14 / 00176, para Francisco Javier Martín RomeropeerReviewe

    Habitat and Scale Shape the Demographic Fate of the Keystone Sea Urchin Paracentrotus lividus in Mediterranean Macrophyte Communities

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    Demographic processes exert different degrees of control as individuals grow, and in species that span several habitats and spatial scales, this can influence our ability to predict their population at a particular life-history stage given the previous life stage. In particular, when keystone species are involved, this relative coupling between demographic stages can have significant implications for the functioning of ecosystems. We examined benthic and pelagic abundances of the sea urchin Paracentrotus lividus in order to: 1) understand the main life-history bottlenecks by observing the degree of coupling between demographic stages; and 2) explore the processes driving these linkages. P. lividus is the dominant invertebrate herbivore in the Mediterranean Sea, and has been repeatedly observed to overgraze shallow beds of the seagrass Posidonia oceanica and rocky macroalgal communities. We used a hierarchical sampling design at different spatial scales (100 s, 10 s and <1 km) and habitats (seagrass and rocky macroalgae) to describe the spatial patterns in the abundance of different demographic stages (larvae, settlers, recruits and adults). Our results indicate that large-scale factors (potentially currents, nutrients, temperature, etc.) determine larval availability and settlement in the pelagic stages of urchin life history. In rocky macroalgal habitats, benthic processes (like predation) acting at large or medium scales drive adult abundances. In contrast, adult numbers in seagrass meadows are most likely influenced by factors like local migration (from adjoining rocky habitats) functioning at much smaller scales. The complexity of spatial and habitat-dependent processes shaping urchin populations demands a multiplicity of approaches when addressing habitat conservation actions, yet such actions are currently mostly aimed at managing predation processes and fish numbers. We argue that a more holistic ecosystem management also needs to incorporate the landscape and habitat-quality level processes (eutrophication, fragmentation, etc.) that together regulate the populations of this keystone herbivore

    Professional quality of life and organizational changes: a five-year observational study in Primary Care

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    <p>Abstract</p> <p>Background</p> <p>The satisfaction and the quality of life perceived by professionals have implications for the performance of health organizations. We have assessed the variations in professional quality of life (PQL) and their explanatory factors during a services management decentralization process.</p> <p>Methods</p> <p>It was designed as a longitudinal analytical observational study in a Health Area in Madrid, Spain. Three surveys were sent out during an ongoing management decentralization process between 2001 and 2005. The professionals surveyed were divided into three groups: Group I (97.3% physicians), group II (92.5% nurses) and group III (auxiliary personnel). Analysis of the tendency and elaboration of an explanatory multivariate model was made. The PQL -35 questionnaire, based on Karasek's demand-control theory, was used to measure PQL. This questionnaire recognizes three PQL dimensions: management support (MS), workload (WL) and intrinsic motivation (IM).</p> <p>Results</p> <p>1444 responses were analyzed. PQL increased 0.16 (CI 95% 0.04 – 0.28) points in each survey. Group II presents over time a higher PQL score than group I of 0.38 (IC 95% 0.18 – 0.59) points. There is no difference between groups I and III.</p> <p>For each point that MS increases, PQL increases between 0.44 and 0.59 points. PQL decreases an average of between 0.35 and 0.49 point, for each point that WL increases.</p> <p>Age appears to have a marginal association with PQL (CI 95% 0.00 – 0.02), as it occurs with being single or not having a stable relationship (CI 95% 0.01 – 0.41). Performing management tasks currently or in the past is related to poorer PQL perception (CI 95% -0.45 – -0.06), and the same occurs with working other than morning shifts (CI 95% -0.03 – -0.40 points).</p> <p>PQL is not related to sex, location of the centre (rural/urban), time spent working in the organization or contractual situation.</p> <p>Conclusion</p> <p>With the improvement in work control and avoiding increases in workloads, PQL perception can be maintained despite deep organizational changes at the macro-management level. Different professional groups experience different perceptions depending on how the changes impact their position in the organization.</p

    Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

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    OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

    The LHC Injection Tests

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    A series of LHC injection tests was performed in August and September 2008. The first saw beam injected into sector 23; the second into sectors 78 and 23; the third into sectors 78-67 and sectors 23-34-45. The fourth, into sectors 23-34-45, was performed the evening before the extended injection test on the 10th September which saw both beams brought around the full circumference of the LHC. The tests enabled the testing and debugging of a number of critical control and hardware systems; testing and validation of instrumentation with beam for the first time; deployment, and validation of a number of measurement procedures. Beam based measurements revealed a number of machine configuration issues that were rapidly resolved. The tests were undoubtedly an essential precursor to the successful start of LHC beam commissioning. This paper provides an outline of preparation for the tests, the machine configuration and summarizes the measurements made and individual system performance

    Objective Evaluation of Multiple Sclerosis Lesion Segmentation using a Data Management and Processing Infrastructure

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    We present a study of multiple sclerosis segmentation algorithms conducted at the international MICCAI 2016 challenge. This challenge was operated using a new open-science computing infrastructure. This allowed for the automatic and independent evaluation of a large range of algorithms in a fair and completely automatic manner. This computing infrastructure was used to evaluate thirteen methods of MS lesions segmentation, exploring a broad range of state-of-theart algorithms, against a high-quality database of 53 MS cases coming from four centers following a common definition of the acquisition protocol. Each case was annotated manually by an unprecedented number of seven different experts. Results of the challenge highlighted that automatic algorithms, including the recent machine learning methods (random forests, deep learning, …), are still trailing human expertise on both detection and delineation criteria. In addition, we demonstrate that computing a statistically robust consensus of the algorithms performs closer to human expertise on one score (segmentation) although still trailing on detection scores
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