2,972 research outputs found
Impact of Neutron Decay Experiments on non-Standard Model Physics
This paper gives a brief overview of the present and expected future limits
on physics beyond the Standard Model (SM) from neutron beta decay, which is
described by two parameters only within the SM. Since more than two observables
are accessible, the problem is over-determined. Thus, precise measurements of
correlations in neutron decay can be used to study the SM as well to search for
evidence of possible extensions to it. Of particular interest in this context
are the search for right-handed currents or for scalar and tensor interactions.
Precision measurements of neutron decay observables address important open
questions of particle physics and cosmology, and are generally complementary to
direct searches for new physics beyond the SM in high-energy physics. Free
neutron decay is therefore a very active field, with a number of new
measurements underway worldwide. We present the impact of recent developments.Comment: 13 pages, 6 figures; Proceedings of the 5th International BEYOND 2010
Conference, Cape Town, South Africa (2010), World Scientific, accepted for
publication; Corrected typo
Selection on feed efficiency in lay hens: direct and correlated response
International audienc
High temperature electromagnetic characterization of thermal protection system tile materials
This study investigated the impact of elevated temperatures on the electromagnetic performance of the LI-2200 thermal protection system. A 15-kilowatt CO2 laser was used to heat an LI-2200 specimen to 3000 F while electromagnetic measurements were performed over the frequency range of l9 to 21 GHz. The electromagnetic measurement system consisted of two Dual-Lens Spot-Focusing (DLSF) antennas, a sample support structure, and an HP-8510B vector network analyzer. Calibration of the electromagnetic system was accomplished with a Transmission-Reflection-Line (TRL) procedure and was verified with measurements on a two-layer specimen of known properties. The results of testing indicated that the LI-2200 system's electromagnetic performance is slightly temperature dependent at temperatures up to 3000 F
Модификация состава лесообразующих пород ЗАО Bakonyerdő в лесничестве Papa
Были исследованы медленно растущие леса из робинии псевдоакации на площади 250 га в лесничестве Pápa ЗАО Bakonyerdő на трех пробных площадях (Egyházaskesző, Kemeneshőgyész, Magyargencs). Леса на выбранных ПП достигнут возраста рубки в течение следующего 10-летнего периода лесной таксации. Задачей работы было выяснение взаимосвязи между параметрами древостоя и индексами выхода древесины
Partial Ordering of Gauge Orbit Types for SU(n)-Gauge Theories
The natural partial ordering of the orbit types of the action of the group of
local gauge transformations on the space of connections in space-time dimension
d<=4 is investigated. For that purpose, a description of orbit types in terms
of cohomology elements of space-time, derived earlier, is used. It is shown
that, on the level of these cohomology elements, the partial ordering relation
is characterized by a system of algebraic equations. Moreover, operations to
generate direct successors and direct predecessors are formulated. The latter
allow to successively reconstruct the set of orbit types, starting from the
principal type.Comment: 35 pages, LaTe
Xenogeneic, extracorporeal liver perfusion in primates improves the ratio of branched-chain amino acids to aromatic amino acids (Fischer's ratio)
In fulminant hepatic failure (FHF), the development of hepatic encephalopathy is associated with grossly abnormal concentrations of plasma amino acids (PAA). Normalization of the ratio of branched-chain amino acids to aromatic amino acids (Fischer's ratio) correlates with clinical improvement. This study evaluated changes in PAA metabolism during 4 h of isolated, normothermic extracorporeal liver perfusion using a newly designed system containing human blood and a rhesus monkey liver. Bile and urea production were within the physiological range. Release of the transaminases AST, ALT and LDH were minimal. The ratio of branched (valine, leucine, isoleucine) to aromatic (tyrosine, phenylalanine) amino acids increased significantly. These results indicate that a xenogeneic extracorporeal liver perfusion system is capable of significantly increasing Fischer's ratio and may play a role in treating and bridging patients in FHF in the future
Schätzung von genetischen parametern der futterver-wertung aus gruppenmittelwerten - dargestellt am beispiel von legehennen
International audienc
V2:Performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz
The performance of the solid deuterium ultra-cold neutron source at the
pulsed reactor TRIGA Mainz with a maximum peak energy of 10 MJ is described.
The solid deuterium converter with a volume of V=160 cm3 (8 mol), which is
exposed to a thermal neutron fluence of 4.5x10^13 n/cm2, delivers up to 550 000
UCN per pulse outside of the biological shield at the experimental area. UCN
densities of ~ 10/cm3 are obtained in stainless steel bottles of V ~ 10 L
resulting in a storage efficiency of ~20%. The measured UCN yields compare well
with the predictions from a Monte Carlo simulation developed to model the
source and to optimize its performance for the upcoming upgrade of the TRIGA
Mainz into a user facility for UCN physics.Comment: 23 pages, 8 figure
Strain and family effects on resistance of "Leghorn" hens against different dissae
International audienc
On the Configuration Space of Gauge Theorie
We investigate the structure of the configuration space of gauge theories and
its description in terms of the set of absolute minima of certain Morse
functions on the gauge orbits. The set of absolute minima that is obtained when
the background connection is a pure gauge is shown to be isomorphic to the
orbit space of the pointed gauge group. We also show that the stratum of
irreducible orbits is geodesically convex, i.e. there are no geometrical
obstructions to the classical motion within the main stratum. An explicit
description of the singularities of the configuration space of SU(2) theories
on a topologically simple space-time and on the lattice is obtained; in the
continuum case we find that the singularities are conical and that the singular
stratum is isomorphic to a Z_2 orbifold of the configuration space of
electrodynamics.Comment: 22 pages [A4] in LaTeX, HD-THEP-94-11, NIKHEF-H/94-1
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