6,872 research outputs found
Characterization of new hybrid pixel module concepts for the ATLAS Insertable B-Layer upgrade
The ATLAS Insertable B-Layer (IBL) collaboration plans to insert a fourth
pixel layer inside the present Pixel Detector to recover from eventual failures
in the current pixel system, especially the b-layer. Additionally the IBL will
ensure excellent tracking, vertexing and b-tagging performance during the LHC
phase I and add robustness in tracking with high luminosity pile-up. The
expected peak luminosity for IBL is 2 to 3centerdot1034 cm-2s-1 and IBL is
designed for an integrated luminosity of 700 fb-1. This corresponds to an
expected fluence of 5centerdot1015 1 MeV neqcm-2 and a total ionizing dose of
250 MRad. In order to cope with these requirements, two new module concepts are
under investigation, both based on a new front end IC, called FE-I4. This IC
was designed as readout chip for future ATLAS Pixel Detectors and its first
application will be the IBL. The planar pixel sensor (PPS) based module concept
benefits from its well understood design, which is kept as similar as possible
to the design of the current ATLAS Pixel Detector sensor. The second approach
of the new three dimensional (3D) silicon sensor technology benefits from the
shorter charge carrier drift distance to the electrodes, which completely
penetrate the sensor bulk. Prototype modules of both sensor concepts have been
build and tested in laboratory and test beam environment before and after
irradiation. Both concepts show very high performance even after irradiation to
5centerdot1015 1 MeV neqcm-2 and meet the IBL specifications in terms of hit
efficiency being larger than 97%. Lowest operational threshold studies have
been effected and prove independent of the used sensor concept the excellent
performance of FE-I4 based module concepts in terms of noise hit occupancy at
low thresholds.Comment: Part of 9th International Conference on Position Sensitive Detectors
(PSD9
Modelling the Northeast Atlantic circulation : implications for the spring invasion of shelf regions by Calanus finmarchicus
The appearance in spring of the copepod Calanus finmarchicus in continental shelf waters of the northeastern Atlantic has been hypothesized to be mainly attributable to invasion from across the continental slope rather than in situ overwintering. This paper describes the application of a hydrodynamic circulation model and a particle-tracking model to Northeast Atlantic waters in order to assess the influence of the flow field and ascent migration parameters on the spring invasion of C. finmarchicus. For hydrodynamic modelling, the Hamburg Shelf-Ocean Model (HAMSOM) was applied to the North Atlantic and Nordic Seas and forced with daily mean atmospheric data. Simulated flow fields from HAMSOM serve as forcing functions for a particle-tracking model of the same region. The robustness of the simulated shelf invasion in three target boxes of the Northeast Atlantic Shelf was assessed by means of a sensitivity analysis with respect to variations in four key migration parameters: overwintering depth, ascent rate, ascent timing, and depth during residence in upper layers. The invasion of the northern North Sea and Norwegian Shelf waters is more sensitive to ascent migration parameters than invasion of the Faroese Shelf. The main reason for enhanced sensitivity of the North Sea invasion is the time and space-dependent flow structure in the Faroe-Shetland Channel. Dense aggregations of overwintering C. finmarchicus are found in the Channel, but because of the complex flow field only a proportion of the overwintering stock has the capacity to reach the North Sea
Characterization of Thin Pixel Sensor Modules Interconnected with SLID Technology Irradiated to a Fluence of 2\,n/cm
A new module concept for future ATLAS pixel detector upgrades is presented,
where thin n-in-p silicon sensors are connected to the front-end chip
exploiting the novel Solid Liquid Interdiffusion technique (SLID) and the
signals are read out via Inter Chip Vias (ICV) etched through the front-end.
This should serve as a proof of principle for future four-side buttable pixel
assemblies for the ATLAS upgrades, without the cantilever presently needed in
the chip for the wire bonding.
The SLID interconnection, developed by the Fraunhofer EMFT, is a possible
alternative to the standard bump-bonding. It is characterized by a very thin
eutectic Cu-Sn alloy and allows for stacking of different layers of chips on
top of the first one, without destroying the pre-existing bonds. This paves the
way for vertical integration technologies.
Results of the characterization of the first pixel modules interconnected
through SLID as well as of one sample irradiated to \,\neqcm{}
are discussed.
Additionally, the etching of ICV into the front-end wafers was started. ICVs
will be used to route the signals vertically through the front-end chip, to
newly created pads on the backside. In the EMFT approach the chip wafer is
thinned to (50--60)\,m.Comment: Proceedings to PSD
Ultraschall und Arthritis
Zusammenfassung: Die Arthrosonographie ist ein etabliertes und validiertes diagnostisches Verfahren in der Rheumatologie. Durch ihren hohen Weichteilkontrast ist die Sonographie in der Lage, Weichteilveränderungen wie z.B. Synovialisveränderungen zu detektieren. Knorpel- oder Knochenveränderungen im Rahmen einer rheumatoiden Arthritis (RA), einer Spondyloarthritis oder einer Kristallarthritis können teilweise nur sonographisch oder in vielen Fällen zu einem früheren Zeitpunkt als mit der konventionellen Bildgebung erfasst werden. Die Aktivität entzündlicher Veränderungen kann mit Hilfe der Doppler- und Power-Dopplersonographie gut dargestellt werden. In der Früharthritisdiagnostik gewinnt die Sonographie zunehmend an Bedeutung, insbesondere bei undifferenzierter Arthritis und bei unauffälligem Röntgenbefund. Neben der Diagnostik der Früharthritis und dem Therapiemonitoring einer RA erlaubt die Sonographie die Darstellung pathognomonischer Veränderungen bei seronegativen Spondyloarthritiden und Kristallablagerungserkrankungen wie Gicht, Chondrokalzinose und Apatitose. Sonographiegesteuerte diagnostische und therapeutische Interventionen zeichnen sich durch eine extrem hohe Treffsicherheit und Verbesserung der klinischen Wirksamkeit verglichen mit ungesteuerten Verfahren aus. Zusammenfassend nimmt die Sonographie zunehmend einen zentralen Stellenwert ein in der Abklärung und Behandlungssteuerung bei entzündlichen Gelenkerkrankunge
Recommended from our members
Acceptance and commitment therapy as an adjunct to the MOVE! programme: a randomized controlled trial.
ObjectiveThe current study tested the efficacy of an acceptance and commitment therapy (ACT) group intervention for disinhibited eating behaviour as an adjunct to the Veterans Affairs MOVE!© weight management programme.MethodsVeterans (N = 88) with overweight or obesity who completed the MOVE! weight management programme and self-identified as having problems with 'stress-related eating' were randomized to four 2-h weekly ACT sessions or a continued behavioural weight-loss (BWL) intervention. Assessments were completed at baseline, post-treatment and 3- and 6-month follow-up on outcomes of interest including measures of disinhibited eating patterns, obesity-related quality of life, weight-related experiential avoidance and weight.ResultsThe BWL group exhibited significantly greater reductions in binge eating behaviour at post-treatment compared with the ACT group. Significant improvements in other outcomes were found with minimal differences between groups. In both groups, decreases in weight-related experiential avoidance were related to improvements in binge eating behaviour.ConclusionsTaken together, the continued BWL intervention resulted in larger improvements in binge eating behaviour than the ACT intervention. The two groups showed similar improvements in other disinhibited eating outcomes. Future studies are encouraged to determine if more integrated or longer duration of ACT treatment may maximize eating outcomes in MOVE.Trial Registration Number: This trial was registered with ClinicalTrials.gov database (NCT01757847)
Elaboration and TEM structural study of interfaces in composites produced by precipitation
Model ceramic matrix composites have been manufactured in a wide range of materials using the precipitation of a metal (Cu, Ni, Cr) in a ceramic matrix (nitride AIN or oxides MgO, Al2O3) providing, in each case low energy configurations at the heterophase interfaces. In connection to microelectronic applications, copper metallic particles precipitate in AIN after implantation by copper ions and anneal of the ceramic matrix. Faceted particles are imaged by HRTEM and are associated to a low energy structural and chemical configuration. Internal reduction experiments have been carried out on (Mg,Ni)O, (Mg,Cu)O and (Al,Cr)2O3 mixed oxides; the morphology, chemical composition and orientation relationship of the different precipitates are obtained through TEM observations and discussed in terms of interfacial energy and precipitate growth mechanism and kinetics. Conventional and high resolution TEM in conjonction to structural models have allowed a comprehensive description of the interface
Photoassociation of cold atoms with chirped laser pulses: time-dependent calculations and analysis of the adiabatic transfer within a two-state model
This theoretical paper presents numerical calculations for photoassociation
of ultracold cesium atoms with a chirped laser pulse and detailed analysis of
the results. In contrast with earlier work, the initial state is represented by
a stationary continuum wavefunction. In the chosen example, it is shown that an
important population transfer is achieved to vibrational levels in
the vicinity of the v=98 bound level in the external well of the
potential. Such levels lie in the energy range swept by
the instantaneous frequency of the pulse, thus defining a ``photoassociation
window''. Levels outside this window may be significantly excited during the
pulse, but no population remains there after the pulse. Finally, the population
transfer to the last vibrational levels of the ground (6s + 6s)
is significant, making stable molecules. The results are interpreted in the
framework of a two state model as an adiabatic inversion mechanism, efficient
only within the photoassociation window. The large value found for the
photoassociation rate suggests promising applications. The present chirp has
been designed in view of creating a vibrational wavepacket in the excited state
which is focussing at the barrier of the double well potential.Comment: 49 pages, 9 figures, submitted to Phys. Rev.
Stationary Josephson effect in a weak-link between nonunitary triplet superconductors
A stationary Josephson effect in a weak-link between misorientated nonunitary
triplet superconductors is investigated theoretically. The non-self-consistent
quasiclassical Eilenberger equation for this system has been solved
analytically. As an application of this analytical calculation, the
current-phase diagrams are plotted for the junction between two nonunitary
bipolar wave superconducting banks. A spontaneous current parallel to the
interface between superconductors has been observed. Also, the effect of
misorientation between crystals on the Josephson and spontaneous currents is
studied. Such experimental investigations of the current-phase diagrams can be
used to test the pairing symmetry in the above-mentioned superconductors.Comment: 6 pages and 6 figure
Psychologische Prädiktoren für das Auftreten einer Major Depression und einer PTBS nach schweren Unfällen
Theoretischer Hintergrund/Fragestellung: Ziel unserer prospektiven Studie war die Identifikation von Prädiktoren für das Auftreten einer Depression im ersten halben Jahr nach einem Unfall.
Methode: Es wurden 52 Unfallpatienten untersucht. Die Ersterhebung erfolgte innerhalb der ersten sechs Wochen nach dem Unfall.
Ergebnisse: Depressive Patienten gaben kurz nach dem Unfall eine geringere Lebenszufriedenheit und soziale Unterstützung an und berichteten häufiger über psychische Störungen und traumatische Erlebnisse vor dem Unfall als Nicht-Depressive. Außerdem litten sie zum Zeitpunkt der Ersterhebung häufiger unter psychischen Störungen und fühlten sich durch die psychischen Symptome stärker beeinträchtigt.
Schlussfolgerung: Die Ergebnisse legen nahe, dass Patienten mit einem Risiko für die Entwicklung einer Depression bereits kurz nach einem Unfall identifiziert werden können
- …