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81.
82.
We present the first published results of near-infrared single-photon detection in aluminium lumped element kinetic inductance detectors (LEKIDs). Using aluminium as a well-understood material that follows conventional superconductor theory, we discuss and validate a model that describes the energy-resolving performance of a LEKID to single-photon absorption events. We also discuss data analysis techniques used to extract single-photon detections from noisy data. We measure an energy resolution of 662 meV for a 1550 nm photon source which is in close agreement to our model predictions for this non-optimised device limited by generation–recombination noise.  相似文献   
83.
As a result of an increasing industrial demand for very small parts, this paper proposes an extension of the concept of forming limit diagrams for very thin sheets (thicknesses of 0.1 mm) called micro-forming limit diagrams (MFLD). A specific drawing tool of small size was designed and subsequently achieved in the laboratory. The formability of a rolled and annealed 1050A aluminum sheet (99.5%) was characterized and analyzed. Seeing the size of the specimen and the tool, the spacer is replaced by a central electro-discharged smaller thickness. The micro-forming press was coupled with a system for strain measurements based on image analysis with a correlation method. After experimental tests with 7 different geometries, the strains were determined at the beginning of the necking from the various images. Based on this, three methods of determination of the MFLD were proposed (white pixel emergence, polynomial method and strain profile analysis) and compared. Finally, an experimental deep drawing cylindrical cup test rendered it possible to validate the most accurate method for determining the micro-forming limit diagram.  相似文献   
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The assessment of both histological and functional long-term outcomes after cerebral ischemia is increasingly recommended for preclinical studies. Whereas correlations between behavioral impairments and primary ischemic lesion are documented, little is known about their relationships with remote nonischemic regions that undergo secondary degeneration, such as the thalamus. Anesthetized rats were subjected to mild (30 min) or severe (60 min) occlusion of the middle cerebral artery. Two months after ischemia, sensorimotor behavior was assessed according to the neurological score, limb-placing, adhesive-removal, and staircase tests; the final histological lesion was measured after this assessment. Cortical damage was correlated to all transient and long-lasting sensorimotor deficits, whereas striatal lesion was more consistently reflected by the forelimb-placing reflexes and adhesive-removal motor deficits. By contrast, the thalamic atrophy was not correlated to early neurological impairment, but rather to the late sensory deficit at the adhesive-removal test and to the skilled forepaw reaching alteration at the staircase test. This suggests that thalamus contributes, albeit moderately, to the ischemia-induced long-lasting sensorimotor deficits, some of which represent relevant targets for therapeutic interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
Intra-articular drug delivery systems (DDSs) are envisaged as interesting alternative to locally release non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen to reduce pain in patients with osteoarthritis. The present study examines the efficacy of S-(+)-ibuprofen on cartilage degradation as drug candidate for DDS loading. Humeral cartilage and joint capsule explants were collected from healthy sheep shoulder joints and they were cultured in mono- or in co-culture for 13?days with LPS in combination with S-(+)-ibuprofen at 50?µM and 1?mM. S-(+)-ibuprofen (50?µM) blocked prostaglandins production in LPS-activated explants but did not reduce cartilage degradation. By contrast, 1?mM S-(+)-ibuprofen treatment of cartilage explants reduced nitric oxide synthesis by 51% (p?=?0.0072), proteoglycans degradation by 35% (p?=?0.0114) and expression of serum amyloid protein – the main protein induced upon LPS challenge – by 44% (p?相似文献   
87.
Fog formation on transparent substrates constitutes a major challenge in several optical applications requiring excellent light transmission characteristics. Anti-fog coatings are hydrophilic, enabling water to spread uniformly on the surface rather than form dispersed droplets. Despite the development of several anti-fog coating strategies, the long-term stability, adherence to the underlying substrate, and resistance to cleaning procedures are not yet optimal. We report on a polymer-based anti-fog coating covalently grafted onto glass surfaces by means of a multistep process. Glass substrates were first activated by plasma functionalization to provide amino groups on the surface, resulting in the subsequent covalent bonding of the polymeric layers. The anti-fog coating was then created by the successive spin coating of (poly(ethylene-maleic anhydride) (PEMA) and poly(vinyl alcohol) (PVA) layers. PEMA acted as an interface by covalently reacting with both the glass surface amino functionalities and the PVA hydroxyl groups, while PVA added the necessary surface hydrophilicity to provide anti-fog properties. Each step of the procedure was monitored by XPS, which confirmed the successful grafting of the coating. Coating thickness was evaluated by profilometry, nanoindentation, and UV visible light transmission. The hydrophilic nature of the anti-fog coating was assessed by water contact angle (CA), and its anti-fog efficiency was determined visually and tested quantitatively for the first time using an ASTM standard protocol. Results show that the PEMA/PVA coating not only delayed the initial period required for fog formation but also decreased the rate of light transmission decay. Finally, following a 24 hour immersion in water, these PEMA/PVA coatings remained stable and preserved their anti-fog properties.  相似文献   
88.
198 men and 413 women responded to random telephone surveys in Fargo, North Dakota and Memphis, Tennessee. Each S was given the Smoking Attitudes Survey, which assesses generalized health beliefs and health-related problems associated with smoking. Ss' knowledge of smoking-associated diseases and diseases not associated with smoking was also assessed. Stepwise regression analysis of composite knowledge scores revealed 4 predictors of the health consequences of smoking: education, race, smoking status, and income. Smokers reported less knowledge and less concern about health consequences of smoking, were more likely to be male, and were more concerned about health consequences of cholesterol. The best predictor of smokers who had never attempted cessation was their greater concern over weight control, compared with smokers with a history of smoking-cessation attempts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
90.
A method of transfer modelling in partially coherent microscopy is presented. By determining the minimal error between simulated and experimental data by means of a lms technique, it is then possible to retrieve, with accuracy, the linewidth on wafers.  相似文献   
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