1,520 research outputs found
Effective theory for wall-antiwall system
We propose a useful method for deriving the effective theory for a system
where BPS and anti-BPS domain walls coexist. Our method respects an
approximately preserved SUSY near each wall. Due to the finite width of the
walls, SUSY breaking terms arise at tree-level, which are exponentially
suppressed. A practical approximation using the BPS wall solutions is also
discussed. We show that a tachyonic mode appears in the matter sector if the
corresponding mode function has a broader profile than the wall width.Comment: LaTeX file, 30 page, 5 eps figures, references adde
Experimental Control and Characterization of Autophagy in Drosophila
Insects such as the fruit fly Drosophila melanogaster, which fundamentally reorganize their body plan during metamorphosis, make extensive use of autophagy for their normal development and physiology. In the fruit fly, the hepatic/adipose organ known as the fat body accumulates nutrient stores during the larval feeding stage. Upon entering metamorphosis, as well as in response to starvation, these nutrients are mobilized through a massive induction of autophagy, providing support to other tissues and organs during periods of nutrient deprivation. High levels of autophagy are also observed in larval tissues destined for elimination, such as the salivary glands and larval gut. Drosophila is emerging as an important system for studying the functions and regulation of autophagy in an in vivo setting. In this chapter we describe reagents and methods for monitoring autophagy in Drosophila, focusing on the larval fat body. We also describe methods for experimentally activating and inhibiting autophagy in this system and discuss the potential for genetic analysis in Drosophila to identify novel genes involved in autophagy
The algebra of adjacency patterns: Rees matrix semigroups with reversion
We establish a surprisingly close relationship between universal Horn classes
of directed graphs and varieties generated by so-called adjacency semigroups
which are Rees matrix semigroups over the trivial group with the unary
operation of reversion. In particular, the lattice of subvarieties of the
variety generated by adjacency semigroups that are regular unary semigroups is
essentially the same as the lattice of universal Horn classes of reflexive
directed graphs. A number of examples follow, including a limit variety of
regular unary semigroups and finite unary semigroups with NP-hard variety
membership problems.Comment: 30 pages, 9 figure
History of clinical transplantation
How transplantation came to be a clinical discipline can be pieced together by perusing two volumes of reminiscences collected by Paul I. Terasaki in 1991-1992 from many of the persons who were directly involved. One volume was devoted to the discovery of the major histocompatibility complex (MHC), with particular reference to the human leukocyte antigens (HLAs) that are widely used today for tissue matching.1 The other focused on milestones in the development of clinical transplantation.2 All the contributions described in both volumes can be traced back in one way or other to the demonstration in the mid-1940s by Peter Brian Medawar that the rejection of allografts is an immunological phenomenon.3,4 © 2008 Springer New York
Wilson Renormalization Group Analysis of Theories with Scalars and Fermions
The continuous block spin (Wilson) renormalization group equation governing
the scale dependence of the action is constructed for theories containing
scalars and fermions. A locally approximated form of this equation detailing
the structure of a generalized effective potential is numerically analyzed. The
role of the irrelevant operators in the nonperturbative renormalization group
running is elucidated and a comparison with the 1-loop perturbative results is
drawn. Focusing on the spontaneously broken phase of a model possessing a
discrete symmetry forbidding an explicit fermion mass term, mass bounds on both
the scalar and fermion degrees of freedom are established. The effect of the
generalized Yukawa coupling on the scalar mass upper bound is emphasized.Comment: 40, PURD-TH-92-
Corn particle size and pelleting influence on growth performance, fecal shedding, and lymph node infection rates of salmonella enterica serovar typhimurium
Ninety-six pigs (initially 13.8 lb.) were used in a 28-d trial to determine the interactive effects between pelleting and particle size on Salmonella serovar Typhimurium shedding and colonization in a young growing pig model. The experiment was a 2 × 2 factorial arrangement consisting of meal or pelleted diets with fine or coarse ground corn. Pigs were fed the diets 1 wk pre-salmonella inoculation and allotted based on weight to one of four dietary treatments. For the main effect of particle size, pigs fed finer ground corn had significantly improved feed efficiency (P0.82). There was no difference in salmonella infection rates of mesenteric lymph nodes obtained on d 28 between treatments or main effects. Finer grinding and meal diets generally improved growth, feed intake, and
feed efficiency compared to pigs fed coarser
ground or pelleted feeds. However, particle
size or diet form did not alter fecal shedding or mesenteric lymph node infection rates of salmonella organisms in our study
Immunomodulation of intestinal transplant with allograft irradiation and simultaneous donor bone marrow infusion
A study of semi-inclusive charmless decays
We study semi-inclusive charmless decays in detail, such as
, , , where does not contain a charm (anti)quark. We find that
the process () can be particularly
useful for determination of the CKM matrix element . We calculate and
present the branching ratio (BR) of as a function of
, with an estimate of possible uncertainties. It is expected that the
BR is an order of . Our estimation indicates that one can
phenomenologically determine with reasonable accuracy by measuring
the BR of ().Comment: 18 pages, 7 figures; Revtex; version accepted for publication in Eur.
Phys. J.
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