3,340 research outputs found
On BPS bounds in D=4 N=2 gauged supergravity II: general matter couplings and black hole masses
We continue the analysis of BPS bounds started in arXiv:1110.2688, extending
it to the full class of N=2 gauged supergravity theories with arbitrary vector
and hypermultiplets. We derive the general form of the asymptotic charges for
asymptotically flat (M_4), anti-de Sitter (AdS_4), and magnetic anti-de Sitter
(mAdS_4) spacetimes. Some particular examples from black hole physics are given
to explicitly demonstrate how AdS and mAdS masses differ when solutions with
non-trivial scalar profiles are considered.Comment: 21 pages; v2 added reference, published version; v3 minor correction
Reproductive and Related Disorders on Dairy Farms with Different Levels of Welfare Quality
In this paper reproductive results of six dairy cows farms with total of 766 (farm 1 â 107; farm 2 â175; farm 3 â 49; farm 4 â 400; farm 5 â20 and farm 6 â 11 milking cows) with different system of rearing and welfare level were analyzed. A dairy cow reproductive efficiency is a key factor for milk production - impaired reproductive performance is a major cause of reduced production in dairy industry.
Welfare and reproductive disorders data were collected by questionnaire regarding criteria of Animal Need Index (ANI â Bartussek et al., 2000) and compared by multidimensional criteria of total discriminating effect. Possibility of movement, lighting and air quality in the accommodation facility, type and quality of floor, possibility of social contacts with other cows and interaction of stockman with cattle were compared and analysed in respect of farm welfare. In respect to the welfare level of lowest ranked farm (farm 6), farms 1, 2, 3, 4, 5 and 6 were ranked as 4th, 2nd, 1st, 5th, 3rd, and 6th, respectively, but in respect to the reproductive and related disorders occurrence rate lowest ranked farm (farm 4), farms 1, 2, 3, 4, 5 and 6 were ranked as 1st, 4th, 2nd, 6th, 5th and 3rd. Discrepancy derives from the fact that reproduction data were collected for a year, while welfare assessment describes reached level in on particular moment of time, not covering all potential causes of reproductive disorders.
Reduced reproductive success would seem promising as information about poor farm welfare, although good results often are not related to good welfare. Nevertheless, assessed welfare protection level provides important information about herd health and potential reproduction problems, pointing out that there are many opportunities for improving the quality of the welfare of dairy cows, mostly through improving the housing conditions of dairy cows
The Herschel-SPIRE instrument and its in-flight performance
The Spectral and Photometric Imaging REceiver (SPIRE), is the Herschel Space Observatory`s submillimetre camera and spectrometer. It contains a three-band imaging photometer operating at 250, 350 and 500 ÎŒm, and an imaging Fourier-transform spectrometer (FTS) which covers simultaneously its whole operating range of 194â671 ÎŒm (447â1550 GHz). The SPIRE detectors are arrays of feedhorn-coupled bolometers cooled to 0.3 K. The photometer has a field of view of 4ÂŽĂ 8ÂŽ, observed simultaneously in the three spectral bands. Its main operating mode is scan-mapping, whereby the field of view is scanned across the sky to achieve full spatial sampling and to cover large areas if desired. The spectrometer has an approximately circular field of view with a diameter of 2.6ÂŽ. The spectral resolution can be adjusted between 1.2 and 25 GHz by changing the stroke length of the FTS scan mirror. Its main operating mode involves a fixed telescope pointing with multiple scans of the FTS mirror to acquire spectral data. For extended source measurements, multiple position offsets are implemented by means of an internal beam steering mirror to achieve the desired spatial sampling and by rastering of the telescope pointing to map areas larger than the field of view. The SPIRE instrument consists of a cold focal plane unit located inside the Herschel cryostat and warm electronics units, located on the spacecraft Service Module, for instrument control and data handling. Science data are transmitted to Earth with no on-board data compression, and processed by automatic pipelines to produce calibrated science products. The in-flight performance of the instrument matches or exceeds predictions based on pre-launch testing and modelling: the photometer sensitivity is comparable to or slightly better than estimated pre-launch, and the spectrometer sensitivity is also better by a factor of 1.5â2
Approximate Solutions to Fractional Subdiffusion Equations: The heat-balance integral method
The work presents integral solutions of the fractional subdiffusion equation
by an integral method, as an alternative approach to the solutions employing
hypergeometric functions. The integral solution suggests a preliminary defined
profile with unknown coefficients and the concept of penetration (boundary
layer). The prescribed profile satisfies the boundary conditions imposed by the
boundary layer that allows its coefficients to be expressed through its depth
as unique parameter. The integral approach to the fractional subdiffusion
equation suggests a replacement of the real distribution function by the
approximate profile. The solution was performed with Riemann -Liouville
time-fractional derivative since the integral approach avoids the definition of
the initial value of the time-derivative required by the Laplace transformed
equations and leading to a transition to Caputo derivatives. The method is
demonstrated by solutions to two simple fractional subdiffusion equations
(Dirichlet problems): 1) Time-Fractional Diffusion Equation, and 2)
Time-Fractional Drift Equation, both of them having fundamental solutions
expressed through the M-Write function. The solutions demonstrate some basic
issues of the suggested integral approach, among them: a) Choice of the
profile, b) Integration problem emerging when the distribution (profile) is
replaced by a prescribed one with unknown coefficients; c) Optimization of the
profile in view to minimize the average error of approximations; d) Numerical
results allowing comparisons to the known solutions expressed to the M-Write
function and error estimations.Comment: 15 pages, 7 figures, 3 table
Interstellar dust in the BOOMERanG maps
Interstellar dust (ISD) emission is present in the mm-wave maps obtained by the BOOMERanG experiment at intermediate and high Galactic latitudes. We find that, while being sub-dominant at the lower frequencies (90,150, 240 GHz), thermal emission from ISD is dominant at 410 GHz, and is well correlated with the IRAS map at 100 ”m. We find also that the angular power spectrum of ISD fluctuations at 410 GHz is a power law, and its level is negligible with respect to the angular power spectrum of the Cosmic Microwave Background (CMB) at 90 and 150 GHz
MAXIMA: an experiment to measure temperature anisotropy in the cosmic microwave background
We describe the MAXIMA experiment, a balloon-borne measurement designed to
map temperature anisotropy in the Cosmic Microwave Background (CMB) over a wide
range of angular scales (multipole range 80 < l < 800). The experiment consists
of a 1.3 m diameter off-axis Gregorian telescope and a receiver with a 16
element array of bolometers cooled to 100 mK. The frequency bands are centered
at 150, 240, and 410 GHz. The 10' FWHM beam sizes are well matched to the scale
of acoustic peaks expected in the angular power spectrum of the CMB. The first
flight of the experiment in its full configuration was launched in August 1998.
A 122 sq-deg map of the sky was made near the Draco constellation during the 7
hour flight in a region of extremely low galactic dust contamination. This map
covers 0.3% of the sky and has 3200 independent beamsize pixels. We describe
the MAXIMA instrument and its performance during the recent flight.Comment: To appear in proceedings of `3K Cosmology', ed. F Melchiorri,
Conference held Oct 5-10 1998, Rome, 13 pages LaTeX (using aipproc2.sty &
aipproc2.cls), Postscript with higher resolution graphics available at
http://cfpa.berkeley.edu/group/cmb/gen.htm
N,NâČ-Disubstituted Indigos as Readily Available Red-Light Photoswitches with Tunable Thermal Half-Lives
Some rare indigo derivatives have been known for a long time to be photochromic upon irradiation with red light, which should be advantageous for many applications. However, the absence of strategies to tune their thermal half-lives by modular molecular design as well as the lack of proper synthetic methods to prepare a variety of such molecules from the parent indigo dye have so far precluded their use. In this work, several synthetic protocols for N-functionalization have been developed, and a variety of N-alkyl and N-aryl indigo derivatives have been prepared. By installation of electron-withdrawing substituents on the N-aryl moieties, the thermal stability of the Z-isomers could be enhanced while maintaining the advantageous photoswitching properties upon irradiation with red light (660 nm LED). Both experimental data and computational results suggest that the ability to tune thermal stability without affecting the dyes' absorption maxima originates from the twisted geometry of the N-aryl groups. The new indigo photoswitches reported are expected to have a large impact on the development of optical methods and applications in both life and material sciences
Foregrounds in the BOOMERANG-LDB data: a preliminary rms analysis
We present a preliminary analysis of the BOOMERanG LDB maps, focused on
foregrounds. BOOMERanG detects dust emission at moderately low galactic
latitudes () in bands centered at 90, 150, 240, 410 GHz. At higher
Galactic latitudes, we use the BOOMERanG data to set conservative upper limits
on the level of contamination at 90 and 150 GHz. We find that the mean square
signal correlated with the IRAS/DIRBE dust template is less than 3% of the mean
square signal due to CMB anisotropy
BPS black holes in N=2 D=4 gauged supergravities
We construct and analyze BPS black hole solutions in gauged N=2, D=4
supergravity with charged hypermultiplets. A class of solutions can be found
through spontaneous symmetry breaking in vacua that preserve maximal
supersymmetry. The resulting black holes do not carry any hair for the scalars.
We demonstrate this with explicit examples of both asymptotically flat and
anti-de Sitter black holes. Next, we analyze the BPS conditions for
asymptotically flat black holes with scalar hair and spherical or axial
symmetry. We find solutions only in cases when the metric contains ripples and
the vector multiplet scalars become ghost-like. We give explicit examples that
can be analyzed numerically. Finally, we comment on a way to circumvent the
ghost-problem by introducing also fermionic hair.Comment: 40 pages, 2 figures; v2 references added; v3 minor changes, published
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