Bepaling van de optredende temperaturen bij tunnelcompostering van geitenmest

Het doel van het project is om inzicht te krijgen in de composteerbaarheid van geitenmest en het hiermee samenhangende temperatuursverloop . Bepaald dient te worden welke temperaturen tijdens het composteren van geitenmest worden bereikt om op basis daarvan een inschatting te kunnen maken van de mate waarin eventueel aanwezige Q-koorts bacteriën zullen worden afgedood. Hierbij wordt uitgegaan van grootschalige compostering in een mechanisch geventileerde composteertunnelsysteem. Het onderzoek wordt uitgevoerd met mest van Q-koortsvrije geitenbedrijven

Atomic scale characterization of deformation induced interfacial mixing in a Cu/V nanocomposite wire

The microstructure of a Cu/V nanocomposite wire processed by cold drawing was investigated by high resolution transmission electron microscopy and atom probe tomography. The experimental data clearly reveal some deformation induced interfacial mixing where the vanadium filaments are nanoscaled. The mixed layer is a 2nm wide vanadium gradient in the fcc Cu phase. This mechanical mixing leads to the local fragmentation and dissolution of the filaments and to the formation of vanadium super saturated solid solutions in fcc Cu

Feasibility and performances of compressed-sensing and sparse map-making with Herschel/PACS data

The Herschel Space Observatory of ESA was launched in May 2009 and is in operation since. From its distant orbit around L2 it needs to transmit a huge quantity of information through a very limited bandwidth. This is especially true for the PACS imaging camera which needs to compress its data far more than what can be achieved with lossless compression. This is currently solved by including lossy averaging and rounding steps on board. Recently, a new theory called compressed-sensing emerged from the statistics community. This theory makes use of the sparsity of natural (or astrophysical) images to optimize the acquisition scheme of the data needed to estimate those images. Thus, it can lead to high compression factors. A previous article by Bobin et al. (2008) showed how the new theory could be applied to simulated Herschel/PACS data to solve the compression requirement of the instrument. In this article, we show that compressed-sensing theory can indeed be successfully applied to actual Herschel/PACS data and give significant improvements over the standard pipeline. In order to fully use the redundancy present in the data, we perform full sky map estimation and decompression at the same time, which cannot be done in most other compression methods. We also demonstrate that the various artifacts affecting the data (pink noise, glitches, whose behavior is a priori not well compatible with compressed-sensing) can be handled as well in this new framework. Finally, we make a comparison between the methods from the compressed-sensing scheme and data acquired with the standard compression scheme. We discuss improvements that can be made on ground for the creation of sky maps from the data.Comment: 11 pages, 6 figures, 5 tables, peer-reviewed articl

Comparison of MRI properties between multimeric DOTAGA and DO3A gadolinium-dendron conjugates

The inherent lack of sensitivity of MRI needs the development of new Gd contrast agents in order to extend 20Hz,37%, the application of this technique to cellular imaging. For this purpose, two multimeric MR contrast agents obtained by peptidic coupling between an amido amine dendron and GdDOTAGA chelates (premetalation strategy, G1-4GdDOTAGA) or DO3A derivatives which then were postmetalated (G1-4GdDO-3A) have been prepared. By comparison to the monomers, an increase of longitudinal relaxivity has been observed for both structures. Especially for G1-4GdDO-3A, a marked increase is observed between 20 and 60 MHz. This structure differs from G1-4GdDOTAGA by an increased rigidity due to the aromatic linker between each chelate and the organic framework. This has the effect of limiting local rotational movements, which has a positive impact on relaxivity

Integral-field near-infrared spectroscopy of two blue dwarf galaxies: NGC 5253 and He 2-10

We present integral field spectroscopy in the near infrared (NIR) of He 2-10 and NGC 5253, two well known nearby dwarf irregular galaxies showing high star-formation rates. Our data provide an unprecedented detailed view of the interstellar medium and star formation in these galaxies, allowing us to obtain spatially resolved information from the NIR emission and absorption line tracers. We study the spatial distribution and kinematics of different components of the interstellar medium (ISM) mostly through the Bracket series lines, the molecular hydrogen spectrum, [FeII] emission, and CO absorptions. Although the ISM is mostly photo-excited, as derived by the [FeII]/Bry and H2 line ratios, some regions corresponding to non-thermal radio sources show a [FeII]/Bry excess due to a significant contribution of SN driven shocks. In He 2-10 we find that the molecular gas clouds, as traced by CO(2-1) and H2 infrared line, show consistent morphologies and velocities when studied with the two different tracers. Moreover, there is a clear association with the youngest super star clusters as traced by the ionized gas. In the same galaxy we observe a cavity depleted of gas, which is surrounded by some of the most active regions of star formation, that we interpret as a signature of feedback-induced star formation from older episodes of star formation. Finally, we measured high turbulence in the ISM of both galaxies, sigma~30-80 km/s, driven by the high star-formation activity.Comment: 12 pages, 10 figures, accepted for publication in A&

Composition, volume, and aspect ratio dependence of the strain distribution, band lineups and electron effective masses in self-assembled pyramidal In1-xGaxAs/GaAs and SixGe1-x/Si quantum dots

We present a systematic investigation of the strain distribution of self-assembled pyramidal In1-xGaxAs/GaAs and SixGe1-x/Si quantum dots for the case of growth on a (001) substrate. The dependence of the biaxial and hydrostatic components of the strain on the quantum dot volume, aspect ratio, composition, and percentage of alloying x is studied using a method based on a Green's function technique. The dependence of the carriers' confining potentials and the electronic effective mass on the same parameters is then calculated in the framework of eight-band k .p theory. The results for which comparable published data are available are in good agreement with the theoretical values for strain profiles, confining potentials, and electronic effective mass. © 2002 American Institute of Physics

Educação ambiental: implementação de práticas pedagógicas nos 1.º e 2.º ciclos do ensino básico, em tempos de pandemia covid-19

Relatório de Prática de Ensino Supervisionada apresentado à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Ensino do 1.º Ciclo do Ensino Básico e de Matemática e Ciências Naturais no 2.º Ciclo do Ensino BásicoO presente Relatório desenvolve-se no âmbito da Unidade Curricular (UC) Prática de Ensino Supervisionada (PES) II, do Mestrado em Ensino do 1.º Ciclo do Ensino Básico (CEB) e de Matemática e Ciências Naturais no 2.º CEB, da Escola Superior de Educação de Lisboa, Instituto Politécnico de Lisboa. Está organizado em duas partes distintas: a primeira remete para a PES no 1.º e no 2.º CEB, e a segunda remete para a apresentação do estudo empírico, realizado nos dois ciclos com o objetivo principal de desenvolver Educação no Ambiente, no 1.º e no 2.º CEB, em tempos de pandemia COVID 19. Neste sentido, pretendeu-se identificar os desafios do desenvolvimento da Educação Ambiental em tempos de pandemia, nomeadamente no que se refere à ausência de contacto com o meio; explorar os benefícios e identificar as limitações de recursos tecnológicos, para a sensibilização e promoção do contacto com o ambiente; explorar potencialidades da Educação no Ambiente, melhorando as práticas de higiene do sistema respiratório e circulatório; e trabalhar a poluição sonora no contexto da saúde ambiental. A metodologia usada foi de carácter misto, recorrendo-se a técnicas de recolha e tratamento de dados maioritariamente qualitativas, mas também quantitativas. Foram realizados dois estudos de caso em dois contextos distintos - o primeiro, numa turma do 1.º ano, em regime presencial ; e o segundo, numa turma do 6.º ano, em regime de ensino remoto de emergência. Para recolher os dados, recorreu-se à análise documental qualitativa dos produtos realizados pelos alunos e à observação participante. Foi administrado, à turma do 2.º CEB, um questionário com questões de resposta fechada, antes e após a intervenção, sendo os resultados obtidos analisados com o suporte da ferramenta Microsoft Excel, para a análise estatística descritiva dos dados e cálculo de frequências absolutas e relativas das respostas. Os resultados destes dois estudos de caso comprovam ser possível desenvolver Educação Ambiental, numa perspetiva de Saúde Ambiental, em tempos de pandemia, em que o contacto com o meio é menor, mas praticável. É de salientar que o uso de recursos tecnológicos digitais neste estudo facilitou o contacto com o meio envolvente.Abstract This Report was developed within the Curricular Unit (CU) Supervised Teaching Practice (STP) II of the Master “Teaching in the 1st Cycle of Basic Education (CBE) and of Mathematics and Natural Sciences in the 2nd CBE”, at Escola Superior de Educação de Lisboa, Instituto Politécnico de Lisboa. The Report is organized in two distinct parts: the first approaches the STP in the 1st and 2nd CBE, and the second presents the empirical study, implemented in the two cycles, with the main objective of developing Education in the Environment, in the 1st and 2nd CBE, in times of COVID 19 pandemic. It was intended to identify the challenges of the development of Environmental Education in times of pandemic, namely in what concerns the lack of direct contact with the environment; to explore the benefits and identify the limitations of technological resources to raise awareness and promote contact with the environment; to explore the potential of Education in the Environment, specifically in improving the hygiene practices of the respiratory and circulatory system; and to study noise pollution in the context of an environmental health approach. The used methodology was of a mixed nature. The techniques used to collect and process data were mostly qualitative, but also quantitative. Two case studies were carried out in two different contexts - the first, in a first-year class, in presence; and the second, in a 6th grade class, using emergency remote teaching. The techniques used to collect the data were the participant observation and the qualitative documentary analysis of the products made by the students. A questionnaire with closed-ended questions was applied to the 2nd CBE class, before and after the didactic intervention. The Microsoft Excel tool was used to the descriptive statistical analysis of the data and to the calculation of absolute frequencies and relative of the answers. The results of these two case studies prove that it is possible to develop Environmental Education, from an Environmental Health perspective, in times of pandemic, when the contact with the environment is limited, but practicable. It is worth noting the use of digital technological resources in this study that facilitated contact with the environment.N/

Nanomaterials to avoid and destroy protein aggregates

Aggregation of proteins is involved in many disorders. Besides amyloid fibrils, which mostly form in the brain, other kind of protein aggregates can lead, for example, to clots in the blood or floaters in the vitreous of the eye. This review aims to overview on how nanomaterials could be employed to avoid and destroy most diverse protein aggregates. Indeed, thanks to their recognized versatility, (stimuli-responsive) nanomaterials may offer attractive features against harmful protein aggregates. However, despite the many conceptually interesting strategies it appears that most important information on both the in vivo efficacy and safety of nanotechnology based prevention or destruction of protein aggregates, which is highly needed to pave the way to clinically relevant therapies, remains missing