816 research outputs found
Optical and RF Metrology for 5G
Specification standards will soon be available for 5G mobile RF
communications. What optical and electrical metrology is needed or available to
support the development of the supporting optical communication systems? Device
measurement, digital oscilloscope impairments and improving system resolution
are discussed.Comment: 2017 IEEE Photonics Society Summer Topical Meeting Series (SUM
Climate Change and the Canadian Higher Education System: An Institutional Policy Analysis
Climate change is a pressing concern. Higher education can address the challenge, but systematic analyses of climate change in education policy are sparse. This paper addresses this gap in the literature by reporting on how Canadian postsecondary educational institutions have engaged with climate change through policy actions. We used descriptive quantitative methods to analyze climate change-specific policies from a representative sample of 50 institutions across Canada and found that nearly half had some form of climate policy. Existing policies were then qualitatively analyzed. We found that the most common form of response focused on the built campus environment, with underdeveloped secondary responses focused on research, curriculum, community engagement, and governance policies. We consider the motivations for such institutional action and end with implications for policy makers and future research.
Le changement climatique est une préoccupation urgente. L’enseignement supérieur peut relever ce défi mais les analyses systématiques du changement climatique dans l’éducation sont rares. Ce document aborde cette lacune dans la littérature en signalant comment les établissements d’enseignement postsecondaires canadiens se sont impliqués dans l’analyse du changement climatique grâce à des mesures politiques. Nous avons utilisé des méthodes quantitatives et descriptives pour analyser ces politiques de changement climatique à partir d’un échantillon représentatif de cinquante établissements canadiens et découvert que plus de la moitié possèdent une politique climatique. Nous les avons analysées de manière qualitative et trouvé que la forme de réponse la plus commune était axée sur le milieu bâti du campus avec des réponses secondaires sous-développées axées sur la recherche, le programme, la participation communautaire et la gouvernance. Nous considérons les motivations de ces mesures institutionnelles et finissons par les implications pour les décisionnaires et les recherches futures
The effect of visual perspective on episodic memory in aging: A virtual reality study.
The possibility of flexibly retrieving our memories using a first-person or a third-person perspective (1PP or 3PP) has been extensively investigated in episodic memory research. Here, we used a Virtual Reality-based paradigm to manipulate the visual perspective used during the encoding stage to investigate age-related differences in the formation of memories experienced from 1PP vs. 3PP. 32 young adults and 32 seniors participated in the study. Participants navigated through two virtual cities to encode complex real-life virtual events, from either a 1PP (as if from their egocentric viewpoint) or a 3PP, while actively controlling an avatar. While recognition accuracy was higher in young adults after encoding in 1PP compared to 3PP, there was no benefit in memory formation in 1PP for older adults. These findings are discussed in terms of both age-related changes in episodic memory functioning and self-referencing processes
A protosolar nebula origin for the ices agglomerated by Comet 67P/Churyumov-Gerasimenko
The nature of the icy material accreted by comets during their formation in
the outer regions of the protosolar nebula is a major open question in
planetary science. Some scenarios of comet formation predict that these bodies
agglomerated from crystalline ices condensed in the protosolar nebula.
Concurrently, alternative scenarios suggest that comets accreted amorphous ice
originating from the interstellar cloud or from the very distant regions of the
protosolar nebula. On the basis of existing laboratory and modeling data, we
find that the N/CO and Ar/CO ratios measured in the coma of the Jupiter
family comet 67P/Churyumov-Gerasimenko by the ROSINA instrument aboard the
European Space Agency's Rosetta spacecraft match those predicted for gases
trapped in clathrates. If these measurements are representative of the bulk
N/CO and Ar/CO ratios in 67P/Churyumov-Gerasimenko, it implies that the
ices accreted by the comet formed in the nebula and do not originate from the
interstellar medium, supporting the idea that the building blocks of outer
solar system bodies have been formed from clathrates and possibly from pure
crystalline ices. Moreover, because 67P/Churyumov-Gerasimenko is impoverished
in Ar and N, the volatile enrichments observed in Jupiter's atmosphere
cannot be explained solely via the accretion of building blocks with similar
compositions and require an additional delivery source. A potential source may
be the accretion of gas from the nebula that has been progressively enriched in
heavy elements due to photoevaporation.Comment: The Astrophysical Journal Letters, in pres
Chinese labour in the global economy: an introduction
This Introduction outlines the main purpose of this special issue volume: to analyse new forms of resistance by Chinese workers against conditions of super-exploitation. After an assessment of the new international division of labour, we provide an overview of Chinese production in the global economy, followed by an introduction of the contributions to this volume
Changes in concentrations of NMDA receptor subunit GluN2B, Arc and syntaxin-1 in dorsal hippocampus Schaffer collateral synapses in a rat learned helplessness model of depression
Major depressive disorder involves changes in synaptic structure and function, but the molecular underpinnings of these changes are still not established. In an initial pilot experiment, whole-brain synaptosome screening with quantitative western blotting was performed to identify synaptic proteins that may show concentration changes in a congenital rat learned helplessness model of depression. We found that the N-methyl-D-aspartate receptor (NMDAR) subunits GluN2A/GluN2B, activityregulated cytoskeleton-associated protein (Arc) and syntaxin-1 showed significant concentration differences between congenitally learned helpless (LH) and nonlearned helpless (NLH) rats. Having identified these three proteins, we then performed more elaborate quantitative immunogold electron microscopic analyses of the proteins in a specific synapse type in the dorsal hippocampus: the Schaffer collateral synapse in the CA1 region. We expanded the setup to include also unstressed wild-type (WT) rats. The concentrations of the proteins in the LH and NLH groups were compared to WT animals. In this specific synapse, we found that the concentration of NMDARs was increased in postsynaptic spines in both LH and NLH rats. The concentration of Arc was significantly increased in postsynaptic densities in LH animals as well as in presynaptic cytoplasm of NLH rats. The concentration of syntaxin-1 was significantly increased in both presynaptic terminals and postsynaptic spines in LH animals, while pre- and postsynaptic syntaxin-1 concentrations were significantly decreased in NLH animals. These protein changes suggest pathways by which synaptic plasticity may be increased in dorsal hippocampal Schaffer collateral synapses during depression, corresponding to decreased synaptic stability.publishedVersio
Virtual Reality as a Vehicle to Empower Motor-Cognitive Neurorehabilitation.
In this paper, we advocate the combination of four key ingredients that we believe are necessary to design long-lasting effective treatments for neurorehabilitation: (i) motor-cognitive training, (ii) evidence-based neuroscience principles, in particular those related to body perception, (iii) motivational games, and (iv) empowerment techniques. Then, we propose virtual reality (VR) as the appropriate medium to encompass all the requirements mentioned above. VR is arguably one of the most suitable technologies for neurorehabilitation able to integrate evidence-based neurorehabilitation techniques and neuroscience principles into motivating training approaches that promote self-management by empowering patients to own their recovery process. We discuss the advantages and challenges of such an approach on several exemplary applications and outline directions for future developments. We strongly believe that the combination of positive psychology and positive technology mediated by VR-based interventions can heavily impact the rehabilitation outcomes of motor-cognitive functions along all the stages of the rehabilitation path
Green fluorescent diamidines as diagnostic probes for trypanosomes
LED fluorescence microscopy offers potential benefits to the diagnosis of human African trypanosomiasis, as well as to other aspects of diseases management, such as detection of drug resistant strains. To advance such approaches reliable and specific fluorescent markers to stain parasites in human fluids are needed. Here we report a series of novel green fluorescent diamidines and their suitability as probes to stain trypanosomes
Commodification and ‘the commons’: the politics of privatising public water in Greece and Portugal during the Eurozone Crisis
In response to the Eurozone crisis, austerity and restructuring has been imposed on the European Union’s (EU) peripheral member states in order to receive financial bailout loans. In addition to cuts in funding of essential public services, cuts in public sector employment and further liberalisation of labour markets, this has also included pressure towards the privatisation of state assets. And yet, workers have not simply accepted these restructuring pressures. They have organised and fought back against austerity and enforced privatisation. Based on a historical materialist perspective and following a strategy of incorporated comparison, in this paper we will comparatively assess the struggles against enforced water privatisation in Greece and Portugal set against the background of the structuring conditions surrounding the Eurozone crisis
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