2,494 research outputs found
Isotope sourcing of prehistoric willow and tule textiles recovered from western Great Basin rock shelters and caves e proof of concept
Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (87Sr/86Sr) and oxygen (18O/16O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope data were useful in showing which plants came from the Humboldt River and which came from rivers headed in the Sierra Nevada
Tachyon Kink on non-BPS Dp-brane in the General Background
This paper is devoted to the study of the tachyon kink on the worldvolume of
a non-BPS Dp-brane that is embedded in general background, including NS-NS two
form B and also general Ramond-Ramond field. We will explicitly show that the
dynamics of the kink is described by the equations of motion that arrise from
the DBI and WZ action for D(p-1)-brane.Comment: 28 page
Deforming tachyon kinks and tachyon potentials
In this paper we investigate deformation of tachyon potentials and tachyon
kink solutions. We consider the deformation of a DBI type action with gauge and
tachyon fields living on D1-brane and D3-brane world-volume. We deform tachyon
potentials to get other consistent tachyon potentials by using properly a
deformation function depending on the gauge field components. Resolutions of
singular tachyon kinks via deformation and applications of deformed tachyon
potentials to scalar cosmology scenario are discussed.Comment: To appear in JHEP, 19 pages, 5 eps figures, minor changes and one
reference adde
Dynamics of D1-brane in I-brane Background
This paper is devoted to the study of the effective field theory description
of the probe D1-brane in the background of the system of two stacks of
fivebranes in type IIB theory that intersect on . We study the
properties of the Dirac-Born-Infeld action for D1-brane moving in this
background. We will argue that this action is invariant under an additional
symmetry in the near horizon limit and that this new symmetry is closely
related to the enhanced symmetry of the I-brane background considered recently
in [hep-th/0508025]. We also solve explicitly the equation of motion of
D1-brane in the near horizon limit.Comment: 21 pages, references adde
Complete N=4 Structure of Low-Energy Effective Action in N=4 Super Yang-Mills Theories
Using the superfield approach, we construct full
supersymmetric low-energy effective actions for SYM models, with
both gauge superfield strengths and hypermultiplet superfields
included. The basic idea is to complete the known non-holomorphic effective
potentials which depend only on superfield strengths and
to the full on-shell invariants by adding the
appropriate superfield hypermultiplet terms. We prove that the effective
potentials of the form can be completed in
this way and present the precise structure of the corresponding completions.
However, the effective potentials of the non-logarithmic form suggested in
hep-th/9811017 and hep-th/9909020 do not admit the completion.
Therefore, such potentials cannot come out as (perturbative or
non-perturbative) quantum corrections in SYM models.Comment: 14 pages, Latex, no figures, slight corrections, refs adde
Warner-Bratzler shear force values and ranges of steaks from cattle of known sires
Carcass data and Warner-Bratzler shear
force (WBSF) data on strip loin steaks were
collected from nearly 8,500 cattle in contemporary groups of progeny from the more popular sires in 14 different beef cattle breeds in the Carcass Merit Traits project funded by Beef Checkoff dollars, the breed associations, and MMI Genomics. In addition, trained sensory panel evaluations were conducted on over 2,500 strip loin steaks from contemporary groups of progeny from five sires included in the DNA marker validation component of the project. The correlation between WBSF and tenderness scored by the trained sensory panel was -0.82, indicating that as WBSF increased, tenderness scored by the sensory panel decreased. Our results showed that a WBSF value of ≥ 11.0 lb generally results in a sensory score of slightly tough or tougher. In this study, 22.8% of the cattle had
WBSF values ≥ 11.0 lb and 26.3% had sensory
scores of slightly tough or tougher. The
phenotypic range of WBSF means for sires
within breeds ranged from 1.9 to 6.6 lb. The
phenotypic range of WBSF means across breeds was 8.9 lb, whereas the range among sires across breeds was a dramatic 14.4 lb. The phenotypic range for flavor intensity
scores among sires within and across breeds
was much smaller than for tenderness, with
juiciness scores being intermediate. The 40
widely used sires that produced progeny with
steaks that were unacceptable in tenderness in this study might be expected to be sires of several thousand bulls used in commercial
herds. This demonstrates that seedstock producers should aggressively utilize sires that have genetics for tender meat
Time Evolution in Superstring Field Theory on non-BPS brane.I. Rolling Tachyon and Energy-Momentum Conservation
We derive equations of motion for the tachyon field living on an unstable
non-BPS D-brane in the level truncated open cubic superstring field theory in
the first non-trivial approximation. We construct a special time dependent
solution to this equation which describes the rolling tachyon. It starts from
the perturbative vacuum and approaches one of stable vacua in infinite time. We
investigate conserved energy functional and show that its different parts
dominate in different stages of the evolution. We show that the pressure for
this solution has its minimum at zero time and goes to minus energy at infinite
time.Comment: 16 pages, 5 figures; minor correction
Bosonic D-brane Effective Action in Linear Dilaton Background
In this paper we will study tachyon effective action for Dp-brane in bosonic
string theory in the linear dilaton background. We obtain the tachyon effective
Lagrangian from boundary state coeficient of Dp-brane in the linear dilaton
background and compare it with tachyon effective Lagrangians that were proposed
in previous papers.Comment: 16 pages, Typos correcte
Entangled Quantum Clocks for Measuring Proper-Time Difference
We report that entangled pairs of quantum clocks (non-degenerate quantum
bits) can be used as a specialized detector for precisely measuring difference
of proper-times that each constituent quantum clock experiences. We describe
why the proposed scheme would be more precise in the measurement of proper-time
difference than a scheme of two-separate-quantum-clocks. We consider
possibilities that the proposed scheme can be used in precision test of the
relativity theory.Comment: no correction, 4 pages, RevTe
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