Measuring star formation in high-z massive galaxies: a mid-infrared to submillimetre study of the GOODS NICMOS Survey sample

We present measurements of the mean mid-infrared to submillimetre flux densities of massive (M_*≳ 10^11 M_⊙) galaxies at redshifts 1.7 < z < 2.9, obtained by stacking positions of known objects taken from the GOODS NICMOS Survey (GNS) catalogue on maps at 24 μm (Spitzer/MIPS); 70, 100 and 160 μm (Herschel/PACS); 250, 350 and 500 μm (BLAST); and 870 μm (LABOCA). A modified blackbody spectrum fit to the stacked flux densities indicates a median [interquartile] star formation rate (SFR) of SFR = 63[48, 81] M_⊙ yr^−1. We note that not properly accounting for correlations between bands when fitting stacked data can significantly bias the result. The galaxies are divided into two groups, disc-like and spheroid-like, according to their Sérsic indices, n. We find evidence that most of the star formation is occurring in n≤ 2 (disc-like) galaxies, with median [interquartile] SFR = 122[100, 150] M_⊙ yr^−1, while there are indications that the n > 2 (spheroid-like) population may be forming stars at a median [interquartile] SFR = 14[9, 20] M_⊙ yr^−1, if at all. Finally, we show that star formation is a plausible mechanism for size evolution in this population as a whole, but find only marginal evidence that it is what drives the expansion of the spheroid-like galaxies.

Far-infrared constraints on the contamination by dust-obscured galaxies of high-z dropout searches

The spectral energy distributions (SED) of dusty galaxies at intermediate redshift may look similar to very high-redshift galaxies in the optical/near infrared (NIR) domain. This can lead to the contamination of high-redshift galaxy searches based on broad-band optical/NIR photometry by lower redshift dusty galaxies because both kind of galaxies cannot be distinguished. The contamination rate could be as high as 50%. This work shows how the far-infrared (FIR) domain can help to recognize likely low-z interlopers in an optical/NIR search for high-z galaxies. We analyze the FIR SEDs of two galaxies that are proposed to be very high-redshift (z > 7) dropout candidates based on deep Hawk-I/VLT observations. The FIR SEDs are sampled with PACS/Herschel at 100 and 160 μm, with SPIRE/Herschel at 250, 350 and 500 μm and with LABOCA/APEX at 870 μm. We find that redshifts > 7 would imply extreme FIR SEDs (with dust temperatures >100 K and FIR luminosities >10^13 L_⊙). At z ~ 2, instead, the SEDs of both sources would be compatible with those of typical ultra luminous infrared galaxies or submillimeter galaxies. Considering all available data for these sources from visible to FIR we re-estimate the redshifts and find z ~ 1.6–2.5. Owing to the strong spectral breaks observed in these galaxies, standard templates from the literature fail to reproduce the visible-to-near-IR part of the SEDs even when additional extinction is included. These sources strongly resemble dust-obscured galaxies selected in Spitzer observations with extreme visible-to-FIR colors, and the galaxy GN10 at z = 4. Galaxies with similar SEDs could contaminate other high-redshift surveys.

The Herschel Lensing Survey (HLS): Overview

The Herschel Lensing Survey (HLS) will conduct deep PACS and SPIRE imaging of ~40 massive clusters of galaxies. The strong gravitational lensing power of these clusters will enable us to penetrate through the confusion noise, which sets the ultimate limit on our ability to probe the Universe with Herschel. Here we present an overview of our survey and a summary of the major results from our science demonstration phase (SDP) observations of the Bullet cluster (z = 0.297). The SDP data are rich and allow us to study not only the background high-redshift galaxies (e. g., strongly lensed and distorted galaxies at z = 2.8 and 3.2) but also the properties of cluster-member galaxies. Our preliminary analysis shows a great diversity of far-infrared/submillimeter spectral energy distributions (SEDs), indicating that we have much to learn with Herschel about the properties of galaxy SEDs. We have also detected the Sunyaev-Zel'dovich (SZ) effect increment with the SPIRE data. The success of this SDP program demonstrates the great potential of the Herschel Lensing Survey to produce exciting results in a variety of science areas.

Improving the identification of high-z Herschel sources with position priors and optical/NIR and FIR/mm photometric redshifts

We present preliminary results about the detection of high redshift (U)LIRGs in the Bullet cluster field by the PACS and SPIRE instruments within the Herschel Lensing Survey (HLS) Program. We describe in detail a photometric procedure designed to recover robust fluxes and deblend faint Herschel sources near the confusion noise. The method is based on the use of the positions of Spitzer/MIPS 24 μm sources as priors. Our catalogs are able to reliably (5σ) recover galaxies with fluxes above 6 and 10 mJy in the PACS 100 and 160 μm channels, respectively, and 12 to 18 mJy in the SPIRE bands. We also obtain spectral energy distributions covering the optical through the far-infrared/millimeter spectral ranges of all the Herschel detected sources, and analyze them to obtain independent estimations of the photometric redshift based on either stellar population or dust emission models. We exemplify the potential of the combined use of Spitzer position priors plus independent optical and IR photometric redshifts to robustly assign optical/NIR counterparts to the sources detected by Herschel and other (sub-)mm instruments.

Tracing the Chromospheric and Coronal Magnetic Field with AIA, IRIS, IBIS, and ROSA Data

The aim of this study is to explore the suitability of chromospheric images for magnetic modeling of active regions. We use high-resolutionimages (≈0.2"-0.3"), from the Interferometric Bidimensional Spectrometer in the Ca II 8542 Å line, the Rapid Oscillations in the Solar Atmosphere instrument in the Hα 6563Å line, the Interface Region Imaging Spectrograph in the 2796Å line, and compare non-potential magnetic field models obtainedfrom those chromospheric images with those obtained from images of the Atmospheric Imaging Assembly in coronal (171 Å, etc.) and inchromospheric (304 Å) wavelengths. Curvi-linear structures are automatically traced in those images with the OCCULT-2 code, to which we forward-fitted magnetic field lines computed with the Vertical-current Approximation Nonlinear Force Free Field code. We find that the chromospheric images: (1) reveal crisp curvi-linear structures (fibrils, loop segments, spicules) that are extremely well-suited for constraining magnetic modeling; (2) that these curvi-linear structures arefield-aligned with the best-fit solution by a median misalignment angle of μ2 ≈ 4°–7° (3) the free energy computed from coronal data may underestimate that obtained from chromospheric data by a factor of ≈2–4, (4) the height range of chromospheric features is confined to h≲4000 km, while coronal features are detected up to h = 35,000 km; and (5) the plasma-β parameter is β ≈ 10^-5 - 10^-1 for all traced features. We conclude that chromospheric images reveal important magnetic structures that are complementary to coronal images and need to be included in comprehensive magnetic field models, something that is currently not accomodated in standard NLFFF codes.

Organisation und Management von Weiterbildung und Lebenslangem Lernen an Hochschulen

Im Bund-Länder-Wettbewerb Aufstieg durch Bildung: offene Hochschulen fokussiert das Teilprojekt Organisation und Management der Universität Oldenburg Erfolgsfaktoren und Hemmnisse zur nachhaltigen Implementierung von Weiterbildung und Lebenslangem Lernen an Hochschulen. Im Spannungsfeld von Kulturen, Strukturen, Strategien und Interessen sowie den sehr spezifischen Governance- und Steuerungsstrukturen von Hochschulen stehen die geförderten Vorhaben vor besonderen Anforderungen, die mit klassischen Instrumenten des Projektmanagements allein kaum zu bewältigen sind. Die bei der Planung, Entwicklung und organisatorischen Verankerung von weiterbildenden Studienangeboten gewählten Lösungsansätze werden aufgezeigt und theoriegeleitet analysiert. Zudem unterstreichen Fallberichte ausgewählter Projekte die mit der nachhaltigen Implementierung von Weiterbildung und Lebenslangem Lernen an Hochschulen verbundenen Herausforderungen und zeigen mögliche Herangehensweisen auf.

Informelles Lernen Studierender mit Social Software unterstützen

E-Learning-Aktivitäten von Hochschulen haben häufig eine einseitige Ausrichtung auf die Unterstützung von Lehrveranstaltungen durch Technologien, insbesondere Lernmanagementsysteme. Dabei geraten die Studierenden als Zielgruppe nur mittelbar in den Blick. Diese Beobachtung nehmen die Autorinnen und Autoren des Bandes zum Anlass, das Lern-Erleben und die unterschiedlichen Phasen des Studiums aus Perspektive der Studierenden zu betrachten. Untersucht wird zudem, welche Unterstützungsangebote Hochschulen in welchen Phasen idealerweise bereitstellen. Die Autorinnen und Autoren formulieren detailliert, wie Hochschulen das studentische Lernen mit Hilfe von Social Software unterstützen können. Diese Empfehlungen basieren auf den Ergebnissen empirischer Untersuchungen sowie auf Fallstudien nationaler und internationaler Beispiele guter Praxis, die ausführlich präsentiert werden. Mit diesem Band möchten die Autorinnen und Autoren denjenigen, die in Bildungseinrichtungen des tertiären Sektors (aber auch in anderen Sektoren) tätig sind, konkrete Anregungen liefern, Unterstützungsangebote für das informelle Lernen von Studierenden mit Social Software stärker in den Blick zu nehmen und geeignete Angebote zu entwickeln. Die Publikation basiert auf Ergebnissen des Projekts „Learner Communities of Practice“, das zwischen 2009 und 2012 als Verbundprojekt sächsischer Hochschulen mit Förderung durch das SMWK unter Leitung des Medienzentrums der TU Dresden bearbeitet wurde.

Emergence and Innovation in Digital Learning: Foundations and Applications

Educational systems worldwide are facing an enormous shift as a result of sociocultural, political, economic, and technological changes. The technologies and practices that have developed over the last decade have been heralded as opportunities to transform both online and traditional education systems. While proponents of these new ideas often postulate that they have the potential to address the educational problems facing both students and institutions and that they could provide an opportunity to rethink the ways that education is organized and enacted, there is little evidence of emerging technologies and practices in use in online education. Because researchers and practitioners interested in these possibilities often reside in various disciplines and academic departments the sharing and dissemination of their work across often rigid boundaries is a formidable task. Contributors to Emergence and Innovation in Digital Learning include individuals who are shaping the future of online learning with their innovative applications and investigations on the impact of issues such as openness, analytics, MOOCs, and social media. Building on work first published in Emerging Technologies in Distance Education, the contributors to this collection harness the dispersed knowledge in online education to provide a one-stop locale for work on emergent approaches in the field. Their conclusions will influence the adoption and success of these approaches to education and will enable researchers and practitioners to conceptualize, critique, and enhance their understanding of the foundations and applications of new technologies.

Federated architecture for biomedical data integration

The last decades have been characterized by a continuous adoption of IT solutions in the healthcare sector, which resulted in the proliferation of tremendous amounts of data over heterogeneous systems. Distinct data types are currently generated, manipulated, and stored, in the several institutions where patients are treated. The data sharing and an integrated access to this information will allow extracting relevant knowledge that can lead to better diagnostics and treatments. This thesis proposes new integration models for gathering information and extracting knowledge from multiple and heterogeneous biomedical sources. The scenario complexity led us to split the integration problem according to the data type and to the usage specificity. The first contribution is a cloud-based architecture for exchanging medical imaging services. It offers a simplified registration mechanism for providers and services, promotes remote data access, and facilitates the integration of distributed data sources. Moreover, it is compliant with international standards, ensuring the platform interoperability with current medical imaging devices. The second proposal is a sensor-based architecture for integration of electronic health records. It follows a federated integration model and aims to provide a scalable solution to search and retrieve data from multiple information systems. The last contribution is an open architecture for gathering patient-level data from disperse and heterogeneous databases. All the proposed solutions were deployed and validated in real world use cases.

Avaliação da dose de radiação: angiotomografia coronariana - métodos retrospectivo e prospectivo

The aim of this study was to evaluate the effective dose received by patients undergoing CCTA in both acquisition methods in the period June 1st to October 30th, 2013. Data collection was performed at the Clínica Sabedotti in Ponta Grossa/PR, with General Electric Equipment VCT XT, 64 detections lines. The effective dose was measured from the thirty cases randomly selected of Picture Archival and Communication System – PACS, reported by Dose Lenght Product (DLP) equipment for each examination and the conversion factor (EDLP) set by the European Commission for cardiac region (EDLP = 0.014). The results showed significant differences in radiation dose delivered to the patient according to the employee acquisition method, Retrospective or Prospective of ECG.

Relatório de Estágio

Este relatório assenta em três pilares essenciais relativos ao trabalho desenvolvido pela mestranda: a exploração teórica de temáticas educativas; a prática educativa supervisionada e o projeto de investigação em educação. No primeiro, analisam-se alguns temas relacionados com a ação docente: o professor enquanto profissional que reflete e investiga; e a indisciplina na sala de aula. No segundo, descreve-se a experiência de estágio da mestranda com a caracterização do contexto do Território Educativo de Intervenção Prioritário, onde a mesma lecionou, e com a reflexão das suas aulas supervisionadas. A sua intervenção educativa seguiu uma metodologia de cariz de investigação-ação, onde a reflexão serviu, destacadamente, para a alteração e o melhoramento das práticas educativas seguintes. O terceiro pilar apresenta o projeto de investigação desenvolvido pela formanda – Semáforo Nutricional: Pare, Olhe e Escolha. Este, inserido na área das Ciências Naturais, procurou potenciar a alteração de hábitos alimentares saudáveis, nos alunos do 1.º e 2.º Ciclo. Assim, fizeram-se sessões de sensibilização em dois contextos educativos e aplicaram-se questionários-testes, antes e depois dessas sessões. Os resultados deste projeto indiciam uma possível alteração dos seus hábitos alimentares. A formanda procurou estabelecer uma constante relação entre a teoria e a prática, fazendo uso dos saberes adquiridos, ao longo da licenciatura e do presente mestrado. Em suma, o relatório constitui uma síntese de todo o seu percurso formativo, no qual se retrata a evolução, a preparação e a superação de desafios, que um professor do 1.º e 2.º Ciclo do Ensino Básico deverá fazer face a cada momento.

Níveis de referência de diagnóstico em procedimentos pediátricos de medicina nuclear

Introdução: A Medicina Nuclear (MN) é uma modalidade imagiológica em grande expansão na atualidade, tornando-se especialmente importante em pediatria. Considerando a elevada radiosensibilidade das crianças, torna-se crucial otimizar os vários procedimentos dentro desta modalidade. Objetivo: Determinar Níveis de Referência de Diagnóstico (NRD’s) para procedimentos de MN Pediátrica num dos centros de excelência nacional e comparar os valores obtidos com a literatura internacional. Material e Métodos: Foi realizada uma análise retrospetiva dos cabeçalhos Digital Imaging and Communications in Medicine (DICOM) de Tomografia por Emissão de Positões (PET-CT) disponíveis no Picture Archiving and Communication System (PACS), de modo a recolher os valores de CT Dose Index (CTDIvol-mGy), Dose Length Product (DLP-mGy.cm), atividade administrada, o género, peso, altura e idade foram recolhidos; De modo a obter os valores de dose relativos a outros procedimentos de MN foram analisados documentos em formato papel. Considerando a idade dos doentes foi estabelecida a categorização etária de forma a determinar os NRD’s locais com base no percentil 75 dos valores de dose. Resultados: Os NRD’s para a atividade administrada em recém-nascidos (0 anos) para a Cintigrafia Renal e Cistografia Direta foi de 26MBq (0,70 e 0,69mCi, respetivamente). Na Renocintigrafia, o valor obtido foi 30MBq (0,80mCi). Para o exame de PET-CT corpo inteiro, os NRD’s para a atividade administrada, CTDIvol e DLP, para os 15 anos foi de 296MBq, 3,23mGy e de 396,79mGy.cm, respectivamente. Para a Cintigrafia do esqueleto o valor obtido para os 15 anos foi de 684MBq (17,5mCi). Conclusões: Após a comparação com os resultados publicados em outros estudos verificaram-se algumas diferenças, sendo os valores de NRD locais obtidos acima dos níveis apresentados.