Modified iterative versus Laplacian Landau gauge in compact U(1) theory

Compact U(1) theory in 4 dimensions is used to compare the modified iterative and the Laplacian fixing to lattice Landau gauge in a controlled setting, since in the Coulomb phase the lattice theory must reproduce the perturbative prediction. It turns out that on either side of the phase transition clear differences show up and in the Coulomb phase the ability to remove double Dirac sheets proves vital on a small lattice.Comment: 14 pages, 8 figures containing 23 graphs, v2: 2 figures removed, 2 references adde

Somatic cell nuclear transfer is associated with altered expression of angiogenic factor systems in bovine placentomes at term

Low efficiency of somatic cell cloning by nuclear transfer has been associated with alterations of placental vascular architecture. Placental growth and function depend on the growth of blood vessels; VEGF-A and bFGF are the most important factors controlling neovascularization and vascular permeability in the placenta. We hypothesize that the VEGF-A and bFGF systems are disrupted in placentomes from cloned animals, contributing to the placental abnormalities that are common in these clones. We determined mRNA expression and protein tissue localization of VEGF-A, bFGF, and their receptors in placentomes from cloned and non-cloned bovine fetuses at term. Real-time RT-PCR revealed that VEGFR-2 mRNA was increased in cloned male-derived placentomes, while mRNA of bFGF and its receptors were decreased in placentomes of cloned females. VEGF-A system proteins were found to be located in placentomal endothelial, maternal and fetal epithelial and stromal cells; there was a variable pattern of cellular distribution of these proteins in both cloned and non-cloned animals. Alterations in the expression of VEGF-A and bFGF systems suggest that angiogenic factors are involved in abnormal placental development in cloned gestations, contributing to impaired fetal development and poor survival ratesFAPESP 02/07392-7CAPES (PROBRAL grant 272/7)\ud CAPES (PROBRAL grant D/06/33937

Removal of a single photon by adaptive absorption

We present a method to remove, using only linear optics, exactly one photon from a field-mode. This is achieved by putting the system in contact with an absorbing environment which is under continuous monitoring. A feedback mechanism then decouples the system from the environment as soon as the first photon is absorbed. We propose a possible scheme to implement this process and provide the theoretical tools to describe it

Tests of Higgs Boson Couplings at a mu+mu- Collider

We investigate the potential of a muon collider for testing the presence of anomalous Higgs boson couplings. We consider the case of a light (less than $160 GeV$) Higgs boson and study the effects on the Higgs branching ratios and total width, which could be induced by the non standard couplings created by a class of dim=6 $SU(3)\times SU(2)\times U(1)$ gauge invariant operators satisfying the constraints imposed by the present and future hadronic and $e^-e^+$ colliders. For each operator we give the minimal value of the $\mu^+\mu^-$ integrated luminosity needed for the muon collider ($\mu C$) to improve these constraints. Depending on the operator and the Higgs mass, this minimal $\mu C$ luminosity lies between $0.1 fb^{-1}$ and $100 fb^{-1}$.Comment: 18 pages and 4 figures; version to be published in Phys. Rev.D. e-mail: [email protected]

Active Brownian Particles. From Individual to Collective Stochastic Dynamics

We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.Comment: 161 pages, Review, Eur Phys J Special-Topics, accepte

Potential alternative feed sources for ruminant feeding from the biodiesel production chain by-products

This study aimed to evaluate the chemical composition, fractionation of nitrogen compounds and carbohydrates, digestibility parameters, gas production kinetics and ruminal fermentation of fruit seed cakes. The experiment was conducted in a completely randomized design with three fruit seed cakes (treatments) and four replications. The cakes were made of seeds of custard apple (Annona squamosa), soursop (Annona muricata) and passion fruit (Passiflora edulis), which were collected in a biodiesel plant. The passion fruit seed cake presented the highest content of dry matter, neutral detergent fibre crude protein (NDFcp), acid detergent fibre (ADF), lignin and total carbohydrates (P<0.05). The custard apple seed cake presented high proportions of crude protein, condensed tannins and digestible energy (P<0.05). The soursop seed cake presented higher values for ether extract and total digestible nutrients (P<0.05). For potential degradability, the authors detected a difference between the custard apple, soursop and passion fruit seed cakes. The total volume of gases was higher for custard apple and soursop seed cakes. Custard apple seed cake presented higher proportions of in vitro degradation parameters (P<0.05). Thus this cake could provide greater nutrient levels when supplied in ruminant diets, followed by soursop seed cake and passion fruit seed cake. Keywords: alternative food, by-products, ruminant feeding, seed cake, semi-ari

Carbohydrate fractionation and nitrogen compounds, mineral status, and gas production in arboreal cotton and cactus silages

ABSTRACT The aim of this study was to evaluate the fractionation of carbohydrates and nitrogen compounds, mineral status, and in vitro gas production of arboreal cotton silages combined with different cactus levels (0, 150, 300, 450 and 600g.kg-1 on dry matter basis), distributed in a completely randomized design with 5 treatments and 4 replicates. For carbohydrate fractionation, there was an increase in fraction B2, and a decrease in fraction C (P<0.05). In nitrogen compounds, there was a decrease in B3 and C fractions (P<0.05). A quadratic effect was observed on mineral matter, crude protein, nitrogen, potassium and latency phase (P<0.05). Under the experimental conditions, the use of cactus in arboreal cotton silages increases the levels of minerals, carbohydrates and gas production in the silage, however, it reduces the protein content in the silages when cactus levels above 150 g.kg are inserted in arboreal cotton silages

Fibrodysplasia ossificans progressiva-like in a cat

Fibrodysplasia ossificans progressiva-like (FOP-like) was diagnosed in a young Brazilian cat presenting progressive lameness, pain upon manipulation and inability to extend the hind limbs. Due to poor response to medication described in the literature, only orchiectomy and confinement of the patient were recommended. The patient described here has been observed for four years and the animal is currently in fair condition despite the movement restrictions

The gene coding for variant hepatic nuclear factor 1 ( Tcf-2 ), maps between the Edp-1 and Erba genes on mouse Chromosome 11

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46992/1/335_2004_Article_BF00352466.pd