17,885 research outputs found
Above the Law: The Prosecutor\u27s Duty to Seek Justice and the Performance of Substantial Assistance Agreements
We study the gravitational-wave (GW) signatures of clouds of ultralight bosons around black holes (BHs) in binary inspirals. These clouds, which are formed via superradiance instabilities for rapidly rotating BHs, produce distinct effects in the population of BH masses and spins, and, for real fields, a continuous monochromatic GW signal. We show that the presence of a binary companion greatly enriches the dynamical evolution of the system, most remarkably through the existence of resonant transitions between the growing and decaying modes of the cloud (analogous to Rabi oscillations in atomic physics). These resonances have rich phenomenological implications for current and future GW detectors. Notably, the amplitude of the GW signal from the clouds may be reduced, and in many cases terminated, much before the binary merger. The presence of a boson cloud can also be revealed in the GW signal from the binary through the imprint of finite-size effects, such as spin-induced multipole moments and tidal Love numbers. The time dependence of the cloud's energy density during the resonance leads to a sharp feature, or at least attenuation, in the contribution from the finite-size terms to the waveforms. The observation of these effects would constrain the properties of putative ultralight bosons through precision GW data, offering new probes of physics beyond the Standard Model
The German Bight (North Sea) is a nursery area for both locally and externally produced sprat juveniles
To better understand the role of the German Bight (GB) as a nursery area for juvenile North Sea sprat Sprattus sprattus we sought to determine whether the area may receive only locally or also externally produced offspring. We sampled juveniles during 3 trawl surveys in the GB in August, September, and October 2004 and applied otolith microstructure analysis in order to reconstruct their distributions of the day-of-first-increment-formation (dif). These were contrasted with spatial and seasonal patterns of sprat egg abundance in the GB and its adjacent areas, observed during 6 monthly plankton surveys. It was found that the majority of juveniles originated mainly from April/May 2004, coinciding with high spawning activity west of the GB, whereas spawning and larval production inside the GB peaked notably later, in May/June. This indicated that a large proportion of juveniles was produced outside the GB and transported subsequently into it through passive and/or active migration. Shifts to later mean difs from one survey to the next and length distributions indicative of the simultaneous presence of multiple cohorts, supported the notion that the GB is a complex retention and nursery area for sprat offspring from different North Sea spawning grounds and times. Later born juveniles had significantly faster initial growth rates than earlier born conspecifics, which was likely temperature-mediated, given the strong correlation between back-calculated growth histories and sea surface temperature as a proxy for thermal histories of juveniles (r(2) = 0.52). (C) 2009 Elsevier B.V. All rights reserved
On the predictive power of Local Scale Invariance
Local Scale Invariance (LSI) is a theory for anisotropic critical phenomena
designed in the spirit of conformal invariance. For a given representation of
its generators it makes non-trivial predictions about the form of universal
scaling functions. In the past decade several representations have been
identified and the corresponding predictions were confirmed for various
anisotropic critical systems. Such tests are usually based on a comparison of
two-point quantities such as autocorrelation and response functions. The
present work highlights a potential problem of the theory in the sense that it
may predict any type of two-point function. More specifically, it is argued
that for a given two-point correlator it is possible to construct a
representation of the generators which exactly reproduces this particular
correlator. This observation calls for a critical examination of the predictive
content of the theory.Comment: 17 pages, 2 eps figure
Experimental assessment of the speed of light perturbation in free-fall absolute gravimeters
Precision absolute gravity measurements are growing in importance, especially
in the context of the new definition of the kilogram. For the case of free-fall
absolute gravimeters with a Michelson-type interferometer tracking the position
of a free falling body, one of the effects that needs to be taken into account
is the speed of light perturbation due to the finite speed of propagation of
light. This effect has been extensively discussed in the past, and there is at
present a disagreement between different studies. In this work, we present the
analysis of new data and confirm the result expected from the theoretical
analysis applied nowadays in free-fall gravimeters. We also review the standard
derivations of this effect (by using phase shift or Doppler effect arguments)
and show their equivalence
Overexpression of alpha(1)-acid glycoprotein in transgenic mice leads to sensitisation to acute colitis.
Coral symbiodinium community composition across the Belize Mesoamerican barrier reef system is influenced by host species and thermal variability
Accepted manuscrip
Universality in D-brane Inflation
We study the six-field dynamics of D3-brane inflation for a general scalar
potential on the conifold, finding simple, universal behavior. We numerically
evolve the equations of motion for an ensemble of more than 7 \times 10^7
realizations, drawing the coefficients in the scalar potential from statistical
distributions whose detailed properties have demonstrably small effects on our
results. When prolonged inflation occurs, it has a characteristic form: the
D3-brane initially moves rapidly in the angular directions, spirals down to an
inflection point in the potential, and settles into single-field inflation. The
probability of N_{e} e-folds of inflation is a power law, P(N_{e}) \propto
N_{e}^{-3}, and we derive the same exponent from a simple analytical model. The
success of inflation is relatively insensitive to the initial conditions: we
find attractor behavior in the angular directions, and the D3-brane can begin
far above the inflection point without overshooting. In favorable regions of
the parameter space, models yielding 60 e-folds of expansion arise
approximately once in 10^3 trials. Realizations that are effectively
single-field and give rise to a primordial spectrum of fluctuations consistent
with WMAP, for which at least 120 e-folds are required, arise approximately
once in 10^5 trials. The emergence of robust predictions from a six-field
potential with hundreds of terms invites an analytic approach to multifield
inflation.Comment: 28 pages, 9 figure
Ageing in disordered magnets and local scale-invariance
The ageing of the bond-disordered two-dimensional Ising model quenched to
below its critical point is studied through the two-time autocorrelator and
thermoremanent magnetization (TRM). The corresponding ageing exponents are
determined. The form of the scaling function of the TRM is well described by
the theory of local scale-invariance.Comment: Latex2e, with epl macros, 7 pages, final for
Persistent photovoltage in methylammonium lead iodide perovskite solar cells
Open circuit voltage decay measurements are performed on methylammonium lead
iodide (CH3NH3PbI3) perovskite solar cells to investigate the charge carrier
recombination dynamics. The measurements are compared to the two reference
polymer-fullerene bulk heterojunction solar cells based on P3HT:PC60BM and
PTB7:PC70BM blends. In the perovskite devices, two very different time domains
of the voltage decay are found, with a first drop on a short time scale that is
similar to the organic solar cells. However, two major differences are also
observed. 65-70% of the maximum photovoltage persists on much longer
timescales, and the recombination dynamics are dependent on the illumination
intensity.Comment: 5 pages, 3 figure
Specifying sickle cell disease interventions: A study protocol of the Sickle Cell Disease Implementation Consortium (SCDIC)
Abstract Background Sickle cell disease (SCD) is an inherited blood disorder that results in a lifetime of anemia, severe pain, and end-organ damage that can lead to premature mortality. While the SCD field has made major medical advances, much needs to be done to improve the quality of care for people with SCD. This study capitalizes on the Sickle Cell Disease Implementation Consortium (SCDIC), a consortium of eight academic sites aiming to test implementation strategies that could lead to more accelerated application of the NHLBI guidelines for treating SCD. This report documents the process to support the consortium by specifying the interventions being developed. Methods This study consists of three steps. The Principal Investigator of each site and two site representatives who are knowledgeable of the intervention (e.g., study coordinator or the person delivering the intervention) will answer an online survey aiming to capture components of the interventions. This survey will be completed by the site representatives three times during the study: during the development of the interventions, after one year of the interventions being implemented, and at the end of this study (after 2 years). A site visit and semi-structured interview (Step 2) in the first year of the process will capture the context of the sites. Step 3 comprises of the development of a framework with the details of the multi-component SCDIC interventions at the sites. Discussion The outcome of this study, a framework of the SCDIC, will enable accurate replication and extension of published research, facilitating the translation of SCD studies to diverse populations and settings and allowing for theory testing of the effects of the intervention components across studies in different contexts and for different populations. Trial registration ClinicalTrial.Gov (#NCT03380351). Registered December 21, 2017
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