1,800 research outputs found
Using a magnete to seperate plastics
No full textFundamental research into magnetic fluids spans more than thirty years, in the course of which a number of practical applications have emerged. Magnetic fluids become heavier when exposed to a magnetic field and can thus be used to separate materials of different densities, with lighter materials floating to the surface. However, since practical fluids took a long time to appear on the scene, development was faltering. Raw materials technologist Dr Peter Rem discovered a new approach, in which separation becomes a viable option for applications like the recycling of plastics and metals, and for refining diamonds. Instead of bulky, energy-hungry electromagnets, the system uses permanent magnets. A patent has been applied for
Life Cycle Assessment of an Innovative Process for PVC Cables Waste Recycling
No full textCable recycling is an important source of high-grade secondary copper. Unfortunately, for every kg of copper produced, the cable recycling process also creates some 2 kg of residue: a complex mixture of PVC insulation, ill-liberated cable parts, very fine copper wire and a minor amount of other materials. This paper investigates two scenarios for this residue in terms of Life Cycle Assessment: land filling versus an innovative process that recycles over 90 mass% of the residue by means of a precise separation on density into a clean PVC fraction and a fine copper product. In order to compare the two scenarios and account for the quality issue of recycled materials, the land filling option is extended with the production of copper and PVC from primary resources, in quantities that represent the same market value as the recycled materials in the recycling scenario. The result of the analysis indicates that, despite this conservative approach, the recycling scenario reduces the relevant impacts by a factor of ten with respect to land filling
Quality control in the recycling stream of PVC cable waste by hyperspectral imaging analysis
No full textThe reduction of EOL concrete disposal in landfills, together with a lower exploitation of primary raw materials, generates a strong interest to develop, set-up and apply innovative technologies to maximize Construction and Demolition Waste (C&DW) conversion into useful secondary raw materials. Such a goal can be reached starting from a punctual in-situ efficient characterization of the objects to dismantle in order to develop demolition actions aimed to set up innovative mechanical-physical processes to recover the different materials and products to recycle. In this paper an innovative recycling-oriented characterization strategy based on HyperSpectral Imaging (HSI) is described in order to identify aggregates and mortar in drill core samples from end-of-life concrete. To reach this goal, concrete drill cores from a demolition site were systematically investigated by HSI in the short wave infrared field (1000-2500 nm). Results obtained by the adoption of the HSI approach showed as this technology can be successfully applied to analyze quality and characteristics of C& DW before dismantling and as final product to re-utilise after demolition-milling-classification actions. The proposed technique and the related recognition logics, through the spectral signature detection of finite physical domains (i.e. concrete slice and/or particle) of different nature and composition, allows; i) to develop characterization procedures able to quantitatively assess end-of-life concrete compositional/textural characteristics and ii) to set up innovative sorting strategies to qualify the different materials constituting drill core samples
Upgrading of PVC rich wastes by magnetic density separation and hyperspectral imaging quality control
No full textPolyvinylchloride (PVC) is one of the most produced polymers in Europe, with a share of 11% in terms of mass (8 million tons) of total polymer consumption, but in 2010 only 5% of the total PVC production came from recycled materials, where other polymer recycling achieves a level of 15% on average. In order to find an innovative process to extract PVC from window frames waste, a combination of two innovative technologies was tested: magnetic density separation (MDS) and hyperspectral imaging (HSI). By its nature, MDS is. a flexible high precision density separation technology that is applicable to any mixture of polymers and contaminants with non-overlapping densities. As PVC has a very distinctive high density, this technology was tested to obtain high-grade PVC pre-concentrates from window frame waste. HSI was used to perform a quality control of the products obtained by MDS showing that PVC was clearly discriminated from unwanted rubber particles of different colors. The results showed that the combined application of MDS and HSI techniques allowed to separate and to check the purity of PVC from window frame waste
London. A Portrait of a City
No full textThis volume inaugurates a new series of publications edited by three leading authors on the world's architectural and artistic scene: H.U.Obrist, Rem Koolhaas and Stefano Boeri. A series of dialogues resulting from the first, "legendary" Serpentine Gallery Marathon, conducted by Hans Ulrich Obrist and Rem Koolhaas, dedicated to London, the description of one of the great metropolises of the world and to the most topical subjects on the international scene. Some of the most innovative protagonists of the British architectural, political, literary, musical and artistic scene (including Brian Eno, Zaha Hadid, Peter Cook, Ron Arad, Doris Lessing, Damien Hirst, Gilbert and George amongst others) have been invited to speak of the near future
NREM to REM sleep transitions and REM sleep microstructure in isolated REM sleep behavior disorder
No full textInternational audienceIntroduction: Isolated rapid eye movement (REM) sleep behaviour disorder (iRBD) is characterised by dream enactment behaviours associated with the loss of physiological atonia during REM sleep. It is considered as a prodromal stage of alpha-synucleinopathies, and may result from dysfunction of brainstem structures controlling muscle tone in REM sleep. Chronic lengthening of non-REM (NREM) to REM transition might be a marker of brainstem reticular formation lesions, as suggested by a study in patients with bulbar forms of post-polio syndrome. Here, we investigated NREM to REM transitions and REM sleep microstructure in the context of iRBD.Method: We retrospectively included patients with iRBD and controls matched for age, sex and apnea-hypopnea index, who underwent full night video-polysomnography. REM sleep without atonia (RSWA, scored as any muscle activity using 3-s mini-epochs on chin EMG), bursts of REMs, and sawtooth waves (STW) bursts were manually marked. Proportion of phasic REM sleep (based on bursts of REMs), STW bursts characteristics (density and duration), and duration between the first STW and the first burst of REMs for each transition (as a proxy of NREM to REM transition) were compared between groups using two-sample t-tests.Results: A total of 20 patients with iRBD (15% female, 64.9 ± 7.7 years old) and 20 controls (25% female, 65.2 ± 6.6 years old)were included. RSWA was 57.4 ± 22.0% in patients with iRBD and 4.6 ± 3.7 in controls (p < 0.001). Phasic REM was increased inpatients with iRBD compared to controls (28.3 ± 12.6% vs. 17.4 ± 6.4%, p = 0.002). No difference was observed between groups forSTW index in REM sleep (1.6 ± 0.5/min vs. 1.7 ± 0.4/min, p = 0.284), and STW bursts duration (3.3 ± 0.8 s vs. 3.2 ± 0.6 s, p = 0.664). However, NREM to REM sleep transitions were significantly longer in patients with iRBD than in controls (232 ± 137 s vs. 139 ± 57 s,p = 0.010).Conclusion: We observed longer NREM to REM transitions in iRBD, which may suggest a major dysregulation of REM sleep, going beyond the well-described loss of muscle atonia and dream enactment behaviours. Further studies are needed to investigate deeper these alterations of REM sleep microstructure, aiming to identify specific clinical phenotypes and predict latency to conversion
NREM to REM sleep transitions and REM sleep microstructure in isolated REM sleep behavior disorder
No full textInternational audienceIntroduction: Isolated rapid eye movement (REM) sleep behaviour disorder (iRBD) is characterised by dream enactment behaviours associated with the loss of physiological atonia during REM sleep. It is considered as a prodromal stage of alpha-synucleinopathies, and may result from dysfunction of brainstem structures controlling muscle tone in REM sleep. Chronic lengthening of non-REM (NREM) to REM transition might be a marker of brainstem reticular formation lesions, as suggested by a study in patients with bulbar forms of post-polio syndrome. Here, we investigated NREM to REM transitions and REM sleep microstructure in the context of iRBD.Method: We retrospectively included patients with iRBD and controls matched for age, sex and apnea-hypopnea index, who underwent full night video-polysomnography. REM sleep without atonia (RSWA, scored as any muscle activity using 3-s mini-epochs on chin EMG), bursts of REMs, and sawtooth waves (STW) bursts were manually marked. Proportion of phasic REM sleep (based on bursts of REMs), STW bursts characteristics (density and duration), and duration between the first STW and the first burst of REMs for each transition (as a proxy of NREM to REM transition) were compared between groups using two-sample t-tests.Results: A total of 20 patients with iRBD (15% female, 64.9 ± 7.7 years old) and 20 controls (25% female, 65.2 ± 6.6 years old)were included. RSWA was 57.4 ± 22.0% in patients with iRBD and 4.6 ± 3.7 in controls (p < 0.001). Phasic REM was increased inpatients with iRBD compared to controls (28.3 ± 12.6% vs. 17.4 ± 6.4%, p = 0.002). No difference was observed between groups forSTW index in REM sleep (1.6 ± 0.5/min vs. 1.7 ± 0.4/min, p = 0.284), and STW bursts duration (3.3 ± 0.8 s vs. 3.2 ± 0.6 s, p = 0.664). However, NREM to REM sleep transitions were significantly longer in patients with iRBD than in controls (232 ± 137 s vs. 139 ± 57 s,p = 0.010).Conclusion: We observed longer NREM to REM transitions in iRBD, which may suggest a major dysregulation of REM sleep, going beyond the well-described loss of muscle atonia and dream enactment behaviours. Further studies are needed to investigate deeper these alterations of REM sleep microstructure, aiming to identify specific clinical phenotypes and predict latency to conversion
Periodic limb movements during REM sleep in multiple sclerosis: a previously undescribed entity
No full textChristian Veauthier,1 Gunnar Gaede,2,3 Helena Radbruch,2 Joern-Peter Sieb,4,5 Klaus-Dieter Wernecke,6,7 Friedemann Paul2,8 1Interdisciplinary Center of Sleep Medicine, Charité University Medicine Berlin, Germany; 2NeuroCure Clinical Research Center, Charité University Medicine Berlin, Germany; 3Department of Neurology, St Joseph Hospital Berlin-Weissensee, Berlin, Germany; 4Department of Neurology, HELIOS Hanseklinikum Stralsund, Stralsund, Germany; 5Department of Neurology, University Hospital Bonn, Bonn, Germany; 6CRO SOSTANA GmbH, Berlin, Germany; 7Institute of Medical Biometry, Charité University Medicine Berlin, Berlin, Germany; 8Clinical and Experimental Multiple Sclerosis Research Center, Department of Neurology, Charité University Medicine Berlin, Berlin, Germany Background: There are few studies describing periodic limb movement syndrome (PLMS) in rapid eye movement (REM) sleep in patients with narcolepsy, restless legs syndrome, REM sleep behavior disorder, and spinal cord injury, and to a lesser extent, in insomnia patients and healthy controls, but no published cases in multiple sclerosis (MS). The aim of this study was to investigate PLMS in REM sleep in MS and to analyze whether it is associated with age, sex, disability, and laboratory findings. Methods: From a study of MS patients originally published in 2011, we retrospectively analyzed periodic limb movements (PLMs) during REM sleep by classifying patients into two subgroups: PLM during REM sleep greater than or equal to ten per hour of REM sleep (n=7) vs less than ten per hour of REM sleep (n=59). A univariate analysis between PLM and disability, age, sex, laboratory findings, and polysomnographic data was performed. Results: MS patients with more than ten PLMs per hour of REM sleep showed a significantly higher disability measured by the Kurtzke expanded disability status scale (EDSS) (P=0.023). The presence of more than ten PLMs per hour of REM sleep was associated with a greater likelihood of disability (odds ratio 22.1; 95% confidence interval 3.5–139.7; P<0.0001), whereas there were no differences in laboratory and other polysomnographic findings. Conclusion: PLMs during REM sleep were not described in MS earlier, and they are associated with disability measured by the EDSS. Keywords: restless legs syndrome, spinal cord, sleep disorders, disability, clinical neurophysiology, polysomnography 
Interoception in REM microstates
No full textHere, we investigated interoceptive processing as quantified by the heartbeat evoked potential (HEP) during REM microstates. We contrasted the HEPs of phasic and tonic REM periods using two separate databases that included the nighttime polysomnographic recordings of 20-20 healthy young individuals. We find a differential HEP modulation of a late HEP component (after 500 ms post-R-peak) between tonic and phasic REM. Moreover, the late tonic HEP component resembled the HEP found in resting wakefulness. Our results indicate that interoception with respect to cardiac signals is not uniform across REM microstates, and suggest that interoceptive processing is partially reinstated during tonic REM periods. The analyses of the HEP during REM sleep may shed new light on the organization and putative function of REM microstates
Interoception in REM microstates
No full textHere, we investigated interoceptive processing as quantified by the heartbeat evoked potential (HEP) during REM microstates. We contrasted the HEPs of phasic and tonic REM periods using two separate databases that included the nighttime polysomnographic recordings of 20-20 healthy young individuals. We find a differential HEP modulation of a late HEP component (after 500 ms post-R-peak) between tonic and phasic REM. Moreover, the late tonic HEP component resembled the HEP found in resting wakefulness. Our results indicate that interoception with respect to cardiac signals is not uniform across REM microstates, and suggest that interoceptive processing is partially reinstated during tonic REM periods. The analyses of the HEP during REM sleep may shed new light on the organization and putative function of REM microstates
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