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Nanotwinned metals and alloys have an attractive suite of properties, but the formation of the underlying nanostructure is generally dependent on the alloy chemistry and processing conditions. This study was undertaken to investigate the effect of deposition rate on nanotwin formation in sputter deposited Ni84Mo11W5 that possess ultrahigh strength and stability. Deposition rates of 0.5–2.3 nm/s were examined and the grain size, texture, twin spacing and hardness were characterized. Minimal variations in the underlying nanostructure and attendant hardness were observed, elucidating a wide processing window and the importance of chemistry on the formation of nanotwins in this alloy.

Advanced metallic alloys are attractive in microelectromechanical systems (MEMS) applications that require high density, electrical and thermal conductivity, strength, and dimensional stability. Here we report the mechanical behavior of direct current (DC) magnetron sputter deposited Nickel (Ni)-Molybdenum (Mo)-Tungsten (W) films annealed at various temperatures. The films deposit as single-phase nanotwinned solid solutions and possess ultra-high tensile strengths of approximately 3 GPa, but negligible ductility. Subsequent heat treatments resulted in grain growth and nucleation of Mo-rich precipitates. While films annealed at 600 °C or 800 °C for 1 h still showed brittle behavior, films annealed at 1,000 °C for 1 h were found to exhibit strength greater than 1.2 GPa and near 10% tensile ductility. In addition to the excellent mechanical properties, alloy films further exhibit remarkably improved dimensional stability – a lower coefficient of thermal expansion and greater microstructural stability. An excellent balance between mechanical properties and dimensional stability make sputter deposited Ni-Mo-W alloys promising structural materials for MEMS applications.

Transformational advances in additive manufacturing combined with the unique functional behavior of shape memory alloys (SMAs) has propelled the field of 4D printing “smart” materials. In this study, we leverage multiple processing pathways with additive manufacturing to design and fabricate SMA components capable of precise, self-guided shape change that could actuate large-scale (up to 25 × 25 × 33 cm3) structures under external thermal stimuli. The dual benefits of minor alloy doping (

The Italian Institute of Nuclear Physics (INFN) is involved in the development of a prototype for a SiPM-based camera for the Cherenkov Telescope Array (CTA), a new generation of telescopes for ground - based gamma ray astronomy. In this framework, an R&D program for the development of SiPMs suitable for Cherenkov light detection (Near-Ultraviolet SiPMs) has been carried out. The developed device is a High Density NUV-SiPM based on a micro cell of 30 μ m × 30 μ m and 6 mm × 6 mm area produced by Fondazione Bruno Kessler (FBK). A full characterisation of the single SiPM will be presented and compared with the old technology (NUV-SiPM) and with other SiPMs commercially available. The NUV-HD SiPM will be tested in the pSCT (Schwarzschild-Couder Telescope prototype) for CTA which is leading to a camera concept based on 8 × 8 NUV-HD SiPM module as detection unit. An update on recent tests on the detectors arranged in this matrix configuration and on the front-end electronics will be given.

Multiwall carbon nanotubes (MWCNTs) consist of multiple layers of graphite sheets arranged in concentric cylinders, from two to many tens. These systems are closely related to graphite layers but in some features, MWCNTs behave quite differently from graphite. In particular, their ability to generate a photocurrent in a wide wavelength range has been demonstrated either without or with the application of a draining voltage. In addition, the photocurrent signal has been found to reproduce the optical absorbance of MWCNTs, showing a maximum in the near UV region. In this paper main characteristics of a novel large area photodetector featuring low noise, high linearity and efficiency are reported. This detector has been obtained by coupling the optoelectronic characteristics of MWCNTs with the well-known properties of silicon. MWCNTs are growth on n-doped silicon layer by chemical vapour deposition creating a p–n heterojunction with high sensitivity to the radiation from UV to IR. An additional MIS junction is obtained with a metallic conductive layer deposited on the back of silicon substrate. Moreover, first results on the signals generated by pulsed laser are also reported.

A mineralogical and geochemical study of minerals on seven types of fracture fillings from near and above the McArthur River unconformity-related uranium deposit has been carried out to determine if fracture filling materials and wall rocks record evidence of primary and secondary dispersion of elements from the deposit. This study shows that Pb extracted by weak acid leaching (2% HNO3) provides Pb-Pb model ages near 1100 Ma for fractures with any of the three REE patterns: 1) LREE-enriched patterns, 2) REE patterns that are concave and similar to uraninite in the deposit, and 3) fractures with flat REE patterns. The REE patterns and ages indicate the fractures are an open system to post-mineralization dispersion of radiogenic Pb from a U-rich source, with a major mobilization of Pb from the uranium deposit at ca. 1100 Ma. Brown (Type 1) fractures, which host Mn-Fe oxides and clay minerals, provide the best evidence of U mineralization through post-mineralization dispersion, containing elevated concentrations of pathfinder elements Co, Ba, Tl, Mn and radiogenic Pb near the surface and at depth. Post-mineralization dispersion is also observed within brown (Type 1) and pink (Type 7; clay minerals + hematite) fractures and wall rock, showing low 207Pb/206Pb values of 0.29–0.50 that were subsequently overprinted by fluids with more common Pb, as recorded in fractures with higher 207Pb/206Pb values of 0.51–0.84. Fracture fillings were analyzed by continuous leach inductively coupled plasma mass spectrometry (CL-ICP-MS) to determine the relationship between trace elements and elemental release from specific mineral phases. CL-ICP-MS results indicate that common Pb (with 207Pb/206Pb values > 0.7) and anomalous Co (360 ppm) and V (220 ppm) contents are resident in organic phases that are dissolved during the 10% H2O2 leach phase. CL-ICP-MS also indicates that radiogenic Pb, as well as Ni and V, are resident in clay minerals and Fe-Mn oxy-hydroxides that break down during leaching with 30% HNO3. Uranium contents are low in the leachate during release of Fe, Al, Mn, and Pb using the 10% and 30% HNO3 leaches, reflecting post-mineralization dispersion of radiogenic Pb, but not U. Thus, secondary dispersion of elements into fractures enhances the size of the deposit footprint, particularly in deep fractures near the P2 fault, but also in some fractures near the surface. The results of this study strongly suggest that fractures did indeed act as conduits for dispersion of elements from the deposit, reaching all the way from deposit to the surface, providing viable exploration targets for U mineralization in sedimentary basins.

Sputter deposited nickel-molybdenum-tungsten (Ni-Mo-W) thin films possess a beneficial suite of properties that stem from the extremely fine growth twins that form during the deposition process. Previously these materials were only characterized in tension, however, in this study in situ micropillar compression and post-mortem microstructural analysis of nanotwinned Ni84Mo11W5 micropillars were employed to measure the compressive response and elucidate the attendant deformation mechanisms. The pillars exhibit Hookean behavior to compressive strengths of 3-3.5 GPa and the onset of non-linear plastic flow was manifest by discrete strain bursts and highly localized shear bands. Plastic deformation was concentrated at the top of the pillar, while the bulk of the micropillar was nominally unaffected. Post-mortem investigations indicate that at sufficiently high stresses shear banding is triggered, resulting in intense and highly localized plastic deformation that led to the formation of twin-free nanocrystalline grains within highly deformed shear bands. By contrast, the regions adjacent to the shear bands were unaffected. The absence of detwinning and dislocation glide mechanisms was unexpected and in direct contrast to what has been observed in nanotwinned Cu-Al. Post-mortem observations of the Ni-Mo-W micropillars suggest that the ultrafine twins create a unique form of dislocation starvation and source-limited plasticity. The ultrahigh compressive strength is governed by the triggering of shear bands rather than the activation of dislocation glide. The specialized nature of plasticity in nanotwinned Ni-Mo-W is clear, even though the precise trigger for shear band formation in nanotwinned Ni-Mo-W remains to be identified.

Near UltraViolet High Density (NUV-HD) SiPMs produced by Fondazione Bruno Kessler in collaboration with INFN have been tested and characterized in INFN laboratories. The third generation of these devices (HD3) has proven to be suitable to equip the focal plane of the prototype Schwarzschild–Couder Medium Size Telescope (pSCT) proposed for the Cherenkov Telescope Array Observatory. Photosensors have been assembled in 4 16-pixel optical units coupled with TARGET–7 ASIC front-end electronics for amplification and digitization of the signal. At present, 9 modules have been successfully integrated on the pSCT camera and are currently taking data. In this contribution we report on the performances of the HD3 technology as single sensor and as assembled optical units, showing their performance and homogeneity in terms of gain and dark count rate.

The majority of microelectromechanical systems (MEMS) are made of silicon, however, future applications will be used in extreme environments, especially at elevated temperatures, and require materials with enhanced properties. Use of metal alloys in these applications will require microscale manufacturability, a balance of physical and mechanical properties and dimensional stability. Here, we emphasized dimensional stability by reducing the coefficient of thermal expansion (CTE) and present an optical non-contact method for measuring the thermal expansion of planar thin films. A combinatorial approach was employed to determine the CTE of nickel-molybdenum-tungsten (Ni-Mo-W) sputter deposited films over a range of compositions, and the addition of Mo and W is shown to significantly decrease and provide a route for tailoring the CTE with compositional control. Ni-Mo-W alloys were revealed to have CTE values ranging from 8–12 × 10−6/°C, matching that of commercial glass substrates that are employed in numerous MEMS devices.

Introduction et but de l’etude La prise en charge de patients obeses massifs constitue un reel challenge pour les equipes soignantes. Ces patients requierent en effet des soins souvent plus compliques a realiser du fait de leur corpulence. Les consequences negatives et parfois stigmatisantes de cette prise en charge difficile ont deja ete bien documentees. Nous avons mene aupres des soignants une formation en simulation de deux jours entre decembre 2015 et mai 2019, au Medical Training Centre d’un hopital universitaire francais. Materiel et methodes Durant la periode de l’etude, differents professionnels de sante issus de diverses unite de soins ont porte une combinaison mimant une obesite massive, entre 30 et 120 minutes selon les sequences de simulation proposees. Ensuite, entre mai et juillet 2019 les participants ont rempli un auto-questionnaire sous forme papier ou electronique. Resultats et analyse statistique Parmi les 215 participants inclus, 47 (21,8 %) ont rempli le questionnaire. 93,6 % des participants ont rapporte un changement dans leurs attitudes, 57.4 % dans leur approche psychologique, 66 % dans la manutention et 70,2 % dans l’utilisation des aides techniques utiles a la manutention de patients obeses massifs, apres la formation en simulation. Suite a cette derniere, 68,1 % des participants ont rapporte un changement de pratique de l’equipe de leurs unites de soins respectives, a la fois concernant l’approche psychologique (31,9 %) et la manutention (48,9 %) des patients obeses. Ces ameliorations se sont maintenues dans le temps, independamment de l’annee de formation des soignants. Un total de 70,2 % des participants ont aussi rapporte un changement des prejuges qu’ils pouvaient avoir concernant l’obesite. Conclusion Notre etude contribue a alimenter la litterature grandissante concernant le besoin de developper des formations educationnelles innovantes pour ameliorer les soins envers les patients obeses et lutter contre la grossophobie medicale.

Discipline Clinique. Introduction et but de l’etude Dans la prise en charge classique medicale ou medicochirurgicale de l’obesite, la re-ascension ponderale est frequemment liee a la survenue ou a la reapparition de compulsions alimentaires. Afin de prendre en compte cette problematique, nous avons propose un traitement ambulatoire pluridisciplinaire (TAP) qui associe un protocole de therapie cognitivo-comportementale (TCC) innovant appele « Meditation basee sur la gestion de l’impulsivite alimentaire » (MBGIA) a un protocole d’hypnose medicale cree a cette intention. Materiel et methodes Les patients obeses compulsifs, inclus dans ce TAP entre fevrier et juin 2018, ont beneficie de 13 seances de 3 modules chacune, dont 8 modules de TCC MBGIA, 4 modules d’hypnose, 6 modules de dietetiques, 2 modules culinaires, 5 modules d’activite physique adaptee, 1 module de socio-esthetique et 13 modules infirmiers avec revue des tâches a domicile. Ils ont rempli des questionnaires avant et apres le TAP pour evaluer leurs poids, taille, comportement alimentaire (EDI-2), anxiete-depression (HAD) et activite physique (Ricci et Gagnon). Resultats et analyse statistique Quarante-cinq patients compulsifs (88,9 % de femmes) d’âge moyen 46,1 ± 15,5 ans et d’IMC moyen 36,8 ± 9,4 kg/m2 ont ete inclus ; ils ont realise en moyenne 9,2 ± 3,4 seances. Les scores de comportement alimentaire global et notamment d’impulsivite alimentaire, d’anxiete, de depression et de pratique d’activite physique ont ete significativement ameliores ( Tableau 1 ). Conclusion Ce traitement integratif alliant TCC et hypnose ameliore la composante compulsive et le bien etre global des patients obeses au decours immediat du programme : il offre de nouvelles perspectives dans la prise en charge de l’obesite et nous incite a confirmer ces resultats par une etude controlee.

Superconducting thin films of the Tl 2 Ba 2 CaCu 2 O x (2212) and Tl 2 Ba 2 Ca 2 Cu 3 O x (2223) phases have been prepared through a combined approach of MOCVD and thallium vapour diffusion. The effects due to the nature of the BaCaCuO(F) precursor matrix on the formation of the TlBaCaCuO phase film have been investigated. Fluorinated [BaCaCuO(F)] matrices have been deposited from Ba(hfa) 2 ·tetraglyme, Ca(hfa) 2 ·tetraglyme and Cu(acac) 2 via metalorganic chemical vapour deposition (MOCVD) on yttria-stabilized zirconia (YSZ) substrates. Both fluorinated [BaCaCuO(F)] and unfluorinated (BaCaCuO) matrices proved suitable for vapour diffusion thallium incorporation using selected Tl 2 O 3 :BaO:CaO:CuO mixtures. The formation of the superconducting 2212 and 2223 films is discussed depending upon the fluorinated and unfluorinated nature of the precursor matrices.

Results concerning the study of the morphology and the surface chemical properties of epitaxial YBCO and highly oriented TBCCO films before and after wet etching processes are reported. X-ray photoemission spectroscopy, Auger electron spectroscopy and scanning electron microscopy are employed to get information on the surface contamination and on the defects of the samples. The chemical modifications of surfaces and the shape of etch pits are discussed.

In this work an electromagnetic non-invasive and contact-less technique using Flux-Gate first-order gradiometer is proposed to detect the magnetic field distribution during electropolishing of copper surface. The electropolishing of the copper surface employed in superconducting RF TESLA-type cavities has been monitored using magnetic field sensors. Local information regarding the dissolved copper surface during the elect ropolishing process has been obtained. An electromagnetic inversion of the magnetic field imaging have been implemented to better understand the effect of the cathode geometry on the electropolishing process. (c) 2006 Elsevier B.V. All rights reserved.

Thyroglossal duct cyst is the most common congenital neck mass in children and young adults. The authors present two cases affecting two patients aged 7 and 9 years, respectively, who had a palpable painless swelling in the submental region. In both patients ultrasound (US) examination showed an anechoic or hypoechoic rounded mass with well-defined margins thus confirming clinical suspicion of thyroglossal duct cyst. One patient also had a second, deep-lying, nonpalpaple cyst which communicated with the superficial cyst. These cases are typical and confirm that US is essential in suspected thyroglossal duct cyst to confirm clinical diagnosis, detect lesions which are not clinically appreciable due to their small size or deep location, to assess communication between the lesions and to detect possible complications.Thyroglossal duct cyst is the most common congenital neck mass in children and young adults. The authors present two cases affecting two patients aged 7 and 9 years, respectively, who had a palpable painless swelling in the submental region. In both patients ultrasound (US) examination showed an anechoic or hypoechoic rounded mass with well-defined margins thus confirming clinical suspicion of thyroglossal duct cyst. One patient also had a second, deep-lying, nonpalpaple cyst which communicated with the superficial cyst. These cases are typical and confirm that US is essential in suspected thyroglossal duct cyst to confirm clinical diagnosis, detect lesions which are not clinically appreciable due to their small size or deep location, to assess communication between the lesions and to detect possible complications.SommarioLe cisti del dotto tireoglosso sono le malformazioni congenite della linea mediana del collo più frequenti nei bambini e nei giovani adulti. Presentiamo due casi di pazienti di 7 e 9 anni, con tumefazioni palpabili in sede sottomentoniera, non dolenti. In entrambi l’ecografia ha evidenziato formazioni anecogene o ipoecogene, rotondeggianti, con margini ben definiti ed è stato confermato il sospetto clinico di cisti del dotto tireoglosso. In un caso il paziente presentava una seconda formazione cistica, non palpabile, profonda, in comunicazione con quella superficiale. I casi presentati sono tipici e confermano come, nel sospetto di cisti del dotto tireoglosso, l’ecografia sia importante, oltre che per la conferma diagnostica, anche per il riconoscimento di lesioni non apprezzabili clinicamente per le dimensioni ridotte o per la sede profonda, per la valutazione dei rapporti delle lesioni e per evidenziare eventuali complicanze.

The Sinding-Larsen-Johansson syndrome has a pathogenesis similar to that of the Osgood-Schlatter disorder and is the result of excessive force exerted by the patellar tendon on the lower pole of the patella. Clinically it is characterized by pain, which increases when the patellar is loaded during flexion, subpatellar swelling and functional limitation. The authors present a case of a 13-year-old boy who was a competitive youth team football player. He presented with anterior, spontaneous knee pain and swelling at the inferior pole of the patella. Ultrasonography (US) confirmed clinical diagnosis showing lesions typical of the Sinding-Larsen-Johansson syndrome. The patient was told to refrain from sports activity; after five months recovery was complete and US follow-up revealed no anomaly. The authors consider the case worthy of reporting because it is paradigmatic and to emphasize the role of US in the evaluation of the Sinding-Larsen-Johansson syndrome.SommarioLa sindrome di Sinding-Larsen-Johansson ha patogenesi simile alla malattia di Osgood-Schlatter, legata all'azione traumatica esercitata dal tendine rotuleo sul polo inferiore della rotula. Clinicamente è caratterizzata da dolore, che aumenta nell'appoggio in flessione, edema sottorotuleo e limitazione funzionale. Il caso in esame si riferisce ad un ragazzo di 13 anni che praticava il calcio, a livello agonistico. Clinicamente presentava dolore al ginocchio, anteriore, spontaneo e tumefazione in corrispondenza del polo inferiore del rotula. L'ecografia evidenziava le lesioni tipiche della sindrome di Sinding-Larsen-Johansson e confermava la diagnosi clinica; veniva prescritta l'astensione dall'attività sportiva. A distanza di cinque mesi si aveva la completa guarigione, con controllo ecografico che confermava l'assenza di lesioni.Abbiamo ritenuto il caso meritevoli di segnalazione perché paradigmatico e per sottolineare il ruolo dell'ecografia nella valutazione della sindrome di Sinding-Larsen-Johansson.

N-Formyl-methionyl-leucyl-phenylalanine (F-MLP)-induced chemotaxis and luminolamplified chemiluminescence were studied in isolated human polymorphonuclear leucocytes (PMN) and exposed to acrylonitrile (ACN) in vitro. Chemotaxis was reduced at ACN concentrations of 3 mm and above, while respiratory burst was affected at ACN concentrations of 18mm and above. The ACN concentrations were highly correlated both with decreased chemotactic activity (r = 0.75; P < 0.05) and with decreased respiratory burst (r = 0.93; P < 0.01).