233 research outputs found

    Faculty Participation in Teaching Improvement Programs

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    A study undertaken to explore faculty nonparticipation in teaching improvement programs is described. Faculty nonparticipation was viewed as a function of interacting personal and situational factors. Questionnaire results, representing 30 percent of the academic faculty at a major university, were compared along disciplinary lines and according to participation in instructional workshops. Responses of past participants and nonparticipants were compared in order to identify variables associated with nonparticipation in instructional development activities. Approximately one-quarter of the 213 respondents had participated in teaching improvement workshops at least once since 1971. Respondents from the Professions and Applied Sciences appeared generally most supportive of the concept of T.I.P. 's while respondents from the Faculty of Science appeared to be the least positive. The study results suggest that faculty nonparticipation in T.I.P. 's may be associated with: the professor's views about teaching and teaching improvement; the relative personal priority assigned to teaching; the perceived need for improvement in teaching skills; attitudes towards the teaching improvement program; awareness of available programs; and the perceived convenience of available programs. The perceived level of university support for good teaching was less clearly associated with nonparticipation, and perceived situational barriers were not found to be associated.Dans ce travail, l'auteur décrit une étude tentant d'explorer la non-participation des enseignants d'une université au programme de perfectionnement de l'enseigne-ment (T.I.P.). La non-participation des enseignants se voit comme étant la consé-quence de l'interaction de facteurs personnels et de facteurs de situations d'enseignement dans lesquelles se trouvent les professeurs. L'auteur a analysé les résultats d'un questionnaire, représentant 30 pour cent du personnel académique d'une université de grande taille selon les disciplines enseignées par les professeurs et selon leur participation aux ateliers d'enseignement. La comparaison des réactions des anciens participants et des non-participants fut effectuée afin d'identifier les variables reliées à la non-participation aux activités de perfectionne-ment. Environ un quart des 213 réponses venaient de professeurs qui avaient participé au moins line fois d des ateliers de perfectionnement de l'enseignement depuis 1971. Les réponses du personnel des professions et des Sciences Appliquées semblaient en général appuyer le concept des ateliers de perfectionnement de l'enseignement tandis que celles du personnel de la Faculté des Sciences semblaient être les moins positives au concept. L'enquête suggère que la non-participation des professeurs aux ateliers de perfectionnement de l'enseignement peut être due aux facteurs suivants: à la philosophie du professeur envers l'enseignement et envers le perfectionnement de son enseignement; à.la priorité personnelle qu'il accorde à l'enseignement; au besoin qu'il éprouve de se perfectionner dans les techniques d'enseignement; aux attitudes qu 'il a envers le programme de perfec-tionnement de l'enseignement; d la connaissance qu 'il a des programmes disponi-bles; et à la disponibilité du professeur vis-â-vis l'horaire des programmes. La per-ception de l'appui universitaire pour un bon enseignement était moins nettement reliée à la non-participation et les difficultés de situations redoutées n 'étaient pas valables

    Spontaneous Growth of Gallium-Filled Microcapillaries on Ion-Bombarded GaN

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    Bottom-up growth of microscopic pillars is observed at room temperature on GaN irradiated with a Ga+ beam in a gaseous XeF2 environment. Ion bombardment produces Ga droplets which evolve into pillars, each comprised of a spherical Ga cap atop a Ga-fille

    Maskless milling of diamond by a focused oxygen ion beam

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    Recent advances in focused ion beam technology have enabled high-resolution, maskless nanofabrication using light ions. Studies with light ions to date have, however, focused on milling of materials where sub-surface ion beam damage does not inhibit device performance. Here we report on maskless milling of single crystal diamond using a focused beam of oxygen ions. Material quality is assessed by Raman and luminescence analysis, and reveals that the damage layer generated by oxygen ions can be removed by non-intrusive post-processing methods such as localised electron beam induced chemical etching

    Direct-write milling of diamond by a focused oxygen ion beam

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    Recent advances in focused ion beam technology have enabled high-resolution, direct-write nanofabrication using light ions. Studies with light ions to date have, however, focused on milling of materials where sub-surface ion beam damage does not inhibit device performance. Here we report on direct-write milling of single crystal diamond using a focused beam of oxygen ions. Material quality is assessed by Raman and luminescence analysis, and reveals that the damage layer generated by oxygen ions can be removed by nonintrusive post-processing methods such as localised electron beam induced chemical etching

    Magnetotransport properties of iron microwires fabricated by focused electron beam induced autocatalytic growth

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    We have prepared iron microwires in a combination of focused electron beam induced deposition (FEBID) and autocatalytic growth from the iron pentacarbonyl, Fe(CO)5, precursor gas under UHV conditions. The electrical transport properties of the microwires were investigated and it was found that the temperature dependence of the longitudinal resistivity (rhoxx) shows a typical metallic behaviour with a room temperature value of about 88 micro{\Omega} cm. In order to investigate the magnetotransport properties we have measured the isothermal Hall-resistivities in the range between 4.2 K and 260 K. From these measurements positive values for the ordinary and the anomalous Hall coefficients were derived. The relation between anomalous Hall resistivity (rhoAN) and longitudinal resistivity is quadratic, rhoAN rho^2 xx, revealing an intrinsic origin of the anomalous Hall effect. Finally, at low temperature in the transversal geometry a negative magnetoresistance of about 0.2 % was measured

    Towards a single step process to create high purity gold structures by electron beam induced deposition at room temperature

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    Highly pure metallic structures can be deposited by electron beam induced deposition and they have many important applications in different fields. The organo-metallic precursor is decomposed and deposited under the electron beam, and typically it is purified with post-irradiation in presence of O2. However, this approach limits the purification to the surface of the deposit. Therefore, 'in situ' purification during deposition using simultaneous flows of both O2 and precursor in parallel with two gas injector needles has been tested and verified. To simplify the practical arrangements, a special concentric nozzle has been designed allowing deposition and purification performed together in a single step. With this new device metallic structures with high purity can be obtained more easily, while there is no limit on the height of the structures within a practical time frame. In this work, we summarize the first results obtained for 'in situ' Au purification using this concentric nozzle, which is described in more detail, including flow simulations. The operational parameter space is explored in order to optimize the shape as well as the purity of the deposits, which are evaluated through scanning electron microscope and energy dispersive x-ray spectroscopy measurements, respectively. The observed variations are interpreted in relation to other variables, such as the deposition yield. The resistivity of purified lines is also measured, and the influence of additional post treatments as a last purification step is studied.EMPA is acknowledged for providing the original code for the GIS simulator model, which was extended by Stan de Muijnck (TU Delft) with the new geometry. Pleun Dona (FEI) is acknowledged for helping in the design of the concentric nozzle and in getting a working prototype. Patricia Peinado is also acknowledged for help on experimental activities. This work was supported by NanoNextNL program, a Dutch national research and technology program for micro- and nano-technology

    Gender and Tahrir Square: contesting the state and imagining a new nation

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    This article argues that the concepts of ‘State’ and ‘Nation’ should be treated as separate from one another, hence, more than one image of the nation is possible at one given time. During the early days of the January 2011 Egyptian revolution, a contestation emerged between Mubarak’s state and the protesters in Tahrir Square over the image and notion of the Egyptian nation. Both the state and the protesters attempted to exclude one another from their respective discourse of the Egyptian nation. While reflecting back on a number of women’s voices who joined the early days of the Tahrir Square protests and using qualitative fieldwork interviews with Cairo-based feminist and political activists, this article points to the complexity of a newly forged image of Egyptian nationhood. In Tahrir Square, this image appeared to be largely framed within gendered criteria where notions of manhood and hyper visible gender equality were intrinsically linked to the broader objective of removing Mubarak and his regime. This raises the question of whether new gender paradigms of equality can continue to exist beyond Tahrir Square’s imagination of a ‘new’ nation

    Shadow Places: Patterns of Spatial Concentration and Incorporation of Irregular Immigrants in the Netherlands

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    Summary: In Western countries, irregular immigrants constitute a sizeable segment of the population. By combining quantitative and qualitative research methods, this article describes and explains irregular immigrants’ patterns of spatial concentration and incorporation in the Netherlands. So far these spatial patterns have not been described and explained systematically, neither in the Netherlands nor elsewhere. The article shows that illegal residence is selectively embedded in the (urban) social structure in various ways. The authors argue that irregular immigrants are likely to be spatially concentrated and incorporated in similar ways in other Western countries; now and in the foreseeable future

    Fibrodysplasia Ossificans Progressiva: what have we achieved and where are we now? follow-up to the 2015 Lorentz Workshop

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    Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare progressive genetic disease effecting one in a million individuals. During their life, patients with FOP progressively develop bone in the soft tissues resulting in increasing immobility and early death. A mutation in the ACVR1 gene was identified as the causative mutation of FOP in 2006. After this, the pathophysiology of FOP has been further elucidated through the efforts of research groups worldwide. In 2015, a workshop was held to gather these groups and discuss the new challenges in FOP research. Here we present an overview and update on these topics

    Mesenchymal Stem Cell Graft Improves Recovery after Spinal Cord Injury in Adult Rats through Neurotrophic and Pro-Angiogenic Actions

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    Numerous strategies have been managed to improve functional recovery after spinal cord injury (SCI) but an optimal strategy doesn't exist yet. Actually, it is the complexity of the injured spinal cord pathophysiology that begets the multifactorial approaches assessed to favour tissue protection, axonal regrowth and functional recovery. In this context, it appears that mesenchymal stem cells (MSCs) could take an interesting part. The aim of this study is to graft MSCs after a spinal cord compression injury in adult rat to assess their effect on functional recovery and to highlight their mechanisms of action. We found that in intravenously grafted animals, MSCs induce, as early as 1 week after the graft, an improvement of their open field and grid navigation scores compared to control animals. At the histological analysis of their dissected spinal cord, no MSCs were found within the host despite their BrdU labelling performed before the graft, whatever the delay observed: 7, 14 or 21 days. However, a cytokine array performed on spinal cord extracts 3 days after MSC graft reveals a significant increase of NGF expression in the injured tissue. Also, a significant tissue sparing effect of MSC graft was observed. Finally, we also show that MSCs promote vascularisation, as the density of blood vessels within the lesioned area was higher in grafted rats. In conclusion, we bring here some new evidences that MSCs most likely act throughout their secretions and not via their own integration/differentiation within the host tissue
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