689 research outputs found
Predicting emotions and meta-emotions at the movies
Audiences are attracted to dramas and horror movies even though negative and ambivalent emotions are likely to be experienced. Research into the seemingly paradoxical enjoyment of this kind of media entertainment has typically focused on gender- and genre-specific needs and viewing motivations. Extending this line of research, the authors focus the role of the need for affect as a more general, gender- and genre-independent predictor of individual differences in the experience of emotions and meta-emotions (i.e., evaluative thoughts and feelings about oneâs emotions). The article discusses a field study of moviegoers who attended the regular screening of a drama or a horror film. Results support the assumption that individuals high in need for affect experience higher levels of negative and ambivalent emotions and evaluate their emotions more positively on the level of meta-emotions. Controlling for the Big Five personality factors does not alter these effects. The results are discussed within an extended meta-emotion framework
Is This Elderly Patient Dehydrated? Diagnostic Accuracy of Hydration Assessment Using Physical Signs, Urine, and Saliva Markers
Critical Analysis of Theoretical Estimates for to Light Meson Form Factors and the Data
We point out that current estimates of form factors fail to explain the
non-leptonic decays and that the combination of data
on the semi-leptonic decays and on the non-leptonic
decays (in particular recent po\-la\-ri\-za\-tion
data) severely constrain the form (normalization and dependence) of the
heavy-to-light meson form factors, if we assume the factorization hypothesis
for the latter. From a simultaneous fit to \bpsi and \dk data we find that
strict heavy quark limit scaling laws do not hold when going from to
and must have large corrections that make softer the dependence on the masses.
We find that should increase slower with \qq than .
We propose a simple parametrization of these corrections based on a quark
model or on an extension of the \hhs laws to the \hl case, complemented with an
approximately constant . We analyze in the light of these data and
theoretical input various theoretical approaches (lattice calculations, QCD sum
rules, quark models) and point out the origin of the difficulties encountered
by most of these schemes. In particular we check the compatibility of several
quark models with the heavy quark scaling relations.Comment: 48 pages, DAPNIA/SPP/94-24, LPTHE-Orsay 94/1
Unraveling loss mechanisms arising from energyâlevel misalignment between metal halide perovskites and hole transport layers
Metal halide perovskites are promising light absorbers for multijunction photovoltaic applications because of their remarkable bandgap tunability, achieved through compositional mixing on the halide site. However, poor energy-level alignment at the interface between wide-bandgap mixed-halide perovskites and charge-extraction layers still causes significant losses in solar-cell performance. Here, the origin of such losses is investigated, focusing on the energy-level misalignment between the valence band maximum and the highest occupied molecular orbital (HOMO) for a commonly employed combination, FA0.83Cs0.17Pb(I1-xBrx)3 with bromide content x ranging from 0 to 1, and poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA). A combination of time-resolved photoluminescence spectroscopy and numerical modeling of charge-carrier dynamics reveals that open-circuit voltage (VOC) losses associated with a rising energy-level misalignment derive from increasing accumulation of holes in the HOMO of PTAA, which then subsequently recombine non-radiatively across the interface via interfacial defects. Simulations assuming an ideal choice of hole-transport material to pair with FA0.83Cs0.17Pb(I1-xBrx)3 show that such VOC losses originating from energy-level misalignment can be reduced by up to 70 mV. These findings highlight the urgent need for tailored charge-extraction materials exhibiting improved energy-level alignment with wide-bandgap mixed-halide perovskites to enable solar cells with improved power conversion efficiencies
Distribution and Abundance of Fin whales and other baleen whales in the European Atlantic
The abundance of fin whales (Balaenoptera physalus) and other baleen whales was generated from data collected during
shipboard sightings surveys as part of the Cetacean Offshore Distribution and Abundance in the European Atlantic project
(CODA). The survey area covered offshore waters beyond the continental shelf of the UK, Ireland, France and Spain. The area
was stratified into four blocks and was surveyed by five ships during July 2007. Double platform methods employing the trialconfiguration
method (BT-method) were used. Fin, sei (B. borealis) and minke whales (B. acutorostrata) were positively
identified, with possible sightings of blue whales (B. musculus). Abundance was estimated for these species and for âlarge baleen
whalesâ which included fin, sei, fin/sei and blue whales. Abundance for the larger species was estimated using the Mark-
Recapture Line Transect design-based method and also model-based methods using density surface modelling. Sample size
limitations dictated that conventional line transect sampling methods were used to estimate the abundance of minke whales.
Estimates from the two methods were comparable but model-based methods improved the precision and were considered best
estimates. The density of large baleen whale species was greatest in the southern end of the survey area and water depth,
temperature and distance to the 2000m contour were important predictors of their distribution. The total abundance estimated for
the entire survey area was 9,019 (CV=0.11) fin whales and 9,619 (CV= 0.11) large baleen whales. The uncertainty around these
estimates due to duplicate classification and species identification were explored. The fin whale estimate is likely to be
underestimated because it excludes unidentified large whales, of which a large proportion was likely to have been fin whales.
Notwithstanding this, these large baleen whale abundance estimates are the first robust estimates (corrected for responsive
movement and g(0)) for this area. The estimated abundance of minke whales was 6,765 (CV=0.99) and sightings were restricted
to the northern blocks of the survey area. The minke whale estimate, although imprecise and likely underestimated, does provide a
baseline figure for this area and, when considered with results from the SCANS-II continental shelf surveys of July 2005, gives a
more comprehensive picture of this species in the European Atlantic. These abundance estimates are important contributions to
the conservation and management of these species in the Northeast Atlantic
Bell inequalities and entanglement in solid state devices
Bell-inequality checks constitute a probe of entanglement -- given a source
of entangled particles, their violation are a signature of the non-local nature
of quantum mechanics. Here, we study a solid state device producing pairs of
entangled electrons, a superconductor emitting Cooper pairs properly split into
the two arms of a normal-metallic fork with the help of appropriate filters. We
formulate Bell-type inequalities in terms of current-current cross-correlators,
the natural quantities measured in mesoscopic physics; their violation provides
evidence that this device indeed is a source of entangled electrons.Comment: 4 pages, 1 figur
Type IIA Moduli Stabilization
We demonstrate that flux compactifications of type IIA string theory can
classically stabilize all geometric moduli. For a particular orientifold
background, we explicitly construct an infinite family of supersymmetric vacua
with all moduli stabilized at arbitrarily large volume, weak coupling, and
small negative cosmological constant. We obtain these solutions from both
ten-dimensional and four-dimensional perspectives. For more general
backgrounds, we study the equations for supersymmetric vacua coming from the
effective superpotential and show that all geometric moduli can be stabilized
by fluxes. We comment on the resulting picture of statistics on the landscape
of vacua.Comment: 48 pages, 2 figures, LaTeX. v2: references added. v3: minor comments
& references adde
FCNC Top Quark Decays in Extra Dimensions
The flavor changing neutral top quark decay t -> c X is computed, where X is
a neutral standard model particle, in a extended model with a single extra
dimension. The cases for the photon, X= \gammaR_\xi gauge. We find that
the branching ratios can be enhanced by the dynamics originated in the extra
dimension. In the limit where 1/R >> ->, we have found Br(t -> c \gamma) \simeq
10^{-10} for 1/R = 0.5 TeV. For the decay t -> c H, we have found Br(t -> cH)
\simeq 10^{-10} for a low Higgs mass value. The branching ratios go to zero
when 1/R -> \infty.Comment: Accepted to be published in the Europ. Phys. Jour. C; 16 pages, 2
figure
Thermally stable perovskite solar cells by all-vacuum deposition
Vacuum deposition is a solvent-free method suitable for growing thin films of metal halide perovskite (MHP) semiconductors. However, most reports of high-efficiency solar cells based on such vacuum-deposited MHP films incorporate solution-processed hole transport layers (HTLs), thereby complicating prospects of industrial upscaling and potentially affecting the overall device stability. In this work, we investigate organometallic copper phthalocyanine (CuPc) and zinc phthalocyanine (ZnPc) as alternative, low-cost, and durable HTLs in all-vacuum-deposited solvent-free formamidinium-cesium lead triodide [CH(NH2)2]0.83Cs0.17PbI3 (FACsPbI3) perovskite solar cells. We elucidate that the CuPc HTL, when employed in an "inverted"p-i-n solar cell configuration, attains a solar-to-electrical power conversion efficiency of up to 13.9%. Importantly, unencapsulated devices as large as 1 cm2 exhibited excellent long-term stability, demonstrating no observable degradation in efficiency after more than 5000 h in storage and 3700 h under 85 °C thermal stressing in N2 atmosphere
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