Quantum fluctuations for drag free geodesic motion

The drag free technique is used to force a proof mass to follow a geodesic motion. The mass is protected from perturbations by a cage, and the motion of the latter is actively controlled to follow the motion of the proof mass. We present a theoretical analysis of the effects of quantum fluctuations for this technique. We show that a perfect drag free operation is in principle possible at the quantum level, in spite of the back action exerted on the mass by the position sensor.Comment: 4 pages, 1 figure, RevTeX, minor change

Beagle 2: Mission to Mars — current status

Beagle 2, developed in the UK, was launched on June 2, 2003. It landed on Mars on December 25th, 2003 in Isidis Planitia, a large sedimentary basin. To date, the team is awaiting signals from the Beagle 2 lander. Current status of the mission will be reported

Evaluating Greek equity funds using data envelopment analysis

This study assesses the relative performance of Greek equity funds employing a non-parametric method, specifically Data Envelopment Analysis (DEA). Using an original sample of cost and operational attributes we explore the e¤ect of each variable on funds' operational efficiency for an oligopolistic and bank-dominated fund industry. Our results have significant implications for the investors' fund selection process since we are able to identify potential sources of inefficiencies for the funds. The most striking result is that the percentage of assets under management affects performance negatively, a conclusion which may be related to the structure of the domestic stock market. Furthermore, we provide evidence against the notion of funds' mean-variance efficiency

Testing the Principle of Equivalence by Solar Neutrinos

We discuss the possibility of testing the principle of equivalence with solar neutrinos. If there exists a violation of the equivalence principle quarks and leptons with different flavors may not universally couple with gravity. The method we discuss employs a quantum mechanical phenomenon of neutrino oscillation to probe into the non-universality of the gravitational couplings of neutrinos. We develop an appropriate formalism to deal with neutrino propagation under the weak gravitational fields of the sun in the presence of the flavor mixing. We point out that solar neutrino observation by the next generation water Cherenkov detectors can improve the existing bound on violation of the equivalence principle by 3-4 orders of magnitude if the nonadiabatic Mikheyev-Smirnov-Wolfenstein mechanism is the solution to the solar neutrino problem.Comment: Latex, 17 pages + 6 uuencoded postscript figures, KEK-TH-396, TMUP-HEL-9402 (unnecessary one reference was removed

The Equivalence Principle in the Non-baryonic Regime

We consider the empirical validity of the equivalence principle for non-baryonic matter. Working in the context of the TH\epsilon\mu formalism, we evaluate the constraints experiments place on parameters associated with violation of the equivalence principle (EVPs) over as wide a sector of the standard model as possible. Specific examples include new parameter constraints which arise from torsion balance experiments, gravitational red shift, variation of the fine structure constant, time-dilation measurements, and matter/antimatter experiments. We find several new bounds on EVPs in the leptonic and kaon sectors.Comment: 22 pages, late

Response to a Salmonella Typhimurium challenge in piglets supplemented with protected sodium butyrate or Bacillus licheniformis : effects on performance, intestinal health and behavior

Salmonella spp. is one of the worldwide leading causes of food-borne illnesses for which the inclusion of probiotics or organic acids in animal feeds can be useful control methods. Experimental models are utilized to test the efficacy of strategies against pathogens, but they exhibit limitations which may preclude finding sensible evaluation parameters. The objective of this work is to evaluate the efficacy of 2 different feed additives; a Bacillus licheniformis based probiotic and a protected sodium butyrate (SB) salt, using an experimental model of salmonellosis and, second, to explore if behavior analysis can be used as a sensible evaluation tool for additives evaluation. A total of 78 piglets weaned at 24 d, 8.3 kg BW, were used. Seventy-two were placed in 3 rooms of 8 pens (3 animals/pen) with evenly distributed treatments (n = 8): CON, control group with plain diet; PRO, plain diet with 1 kg/t of Proporc (10 9 cfu of B. licheniformis /kg of feed), and BUT, plain diet with 3 kg/t of Gustor BP70 (2.1 g of partially protected SB salt/kg of feed). Remaining piglets (n = 6) were separated and used as a challenge negative control. The experiment lasted 16 d. After 1 wk of adaptation, animals were challenged with 5 × 10 8 cfu of Salmonella Typhimurium. One pig per pen was euthanized and sampled at d 4 and 8 post-inoculation (PI). There were no significant differences among treatments for ADFI, ADG, G:F, rectal temperature, fecal consistency, pH, ammonia, short-chain fatty acids and lactic acid concentrations, cytokine TNF-α, Pig-MAP acute-phase proteins and histological parameters. However, both products were equally able to reduce colonization and shedding of Salmonella (P = 0.016 for PRO and BUT vs. CON). In addition, PRO treatment had a positive effect on behavioral displays, particularly exploring (P < 0.05 vs. CON), feeding (P < 0.05 vs. CON and BUT) and other active behaviors (P < 0.05 vs. CON and BUT) in the morning period (0830 to 1030 h). In the afternoon (1400 to 1600 h), the challenge effect was most significant. Pigs were less active after the challenge (P < 0.001), with a decrease in positive contacts (P = 0.004), exploration (P < 0.001) and feeding behaviors (P < 0.001) on d 3 PI, in comparison with before the challenge. Accordingly, many lying conducts increased at d 3 PI (P < 0.05). In conclusion, both treatments had positive effects against Salmonella, and behavior analysis appears to be a sensible tool to be considered

Constraints on the Variations of the Fundamental Couplings

We reconsider several current bounds on the variation of the fine-structure constant in models where all gauge and Yukawa couplings vary in an interdependent manner, as would be expected in unified theories. In particular, we re-examine the bounds established by the Oklo reactor from the resonant neutron capture cross-section of 149Sm. By imposing variations in \Lambda_{QCD} and the quark masses, as dictated by unified theories, the corresponding bound on the variation of the fine-structure constant can be improved by about 2 orders of magnitude in such theories. In addition, we consider possible bounds on variations due to their effect on long lived \alpha- and \beta-decay isotopes, particularly 147Sm and 187Re. We obtain a strong constraint on \Delta \alpha / \alpha, comparable to that of Oklo but extending to a higher redshift corresponding to the age of the solar system, from the radioactive life-time of 187Re derived from meteoritic studies. We also analyze the astrophysical consequences of perturbing the decay Q values on bound state \beta-decays operating in the s-process.Comment: 25 pages, latex, 5 eps figure

Different phytase levels and energy densities in broiler diets on performance, nutrient digestibility, and bone integrity from 28 to 35 days of age.

Abstract: The study was carried out with the objective of evaluating the effects of using phytase levels at different energy densities in the diet of broilers, from 28 to 35 days of age. The experimental diets contained increasing levels of apparent metabolizable energy corrected for nitrogen balance and different levels of phytase. Growth performance variables, nutrient digestibility, as well as variables related to bone integrity were examined. Diets containing 500 FTU/kg in combination with 3150kcal.kg-1 of AMEn resulted in better growth performance. Supplementation with 500 and 1000 FTU/kg in the diets provide better coefficients of apparent and ileal digestibility of calcium and phosphorus, but negatively influence the deposition of calcium, phosphorus, dry matter, and ash in the tibia, in addition to adversely affecting the breakage and area of these bones in broilers. Bone length and the levels of magnesium and zinc present in the tibias were not influenced by the energy and phytase levels of the diets. There is no interaction between the different energetic densities and the phytase doses in the variables analyzed in the studied period. Increasing the energy density of diets resulted in improved apparent and ileal digestibility for most nutrients. Resumo: O estudo foi realizado com o objetivo de avaliar os efeitos da utilização de níveis de fitase em diferentes densidades energéticas na dieta de frangos de corte, no período de 28 a 35 dias de idade. As dietas experimentais contiveram níveis crescentes de energia metabolizável aparente corrigida para balanço de nitrogênio e diferentes níveis de fitase. Foram avaliadas variáveis de desempenho zootécnico, digestibilidade de nutrientes e variáveis relacionadas à integridade óssea. Dietas contendo 500 FTU/kg de fitase em combinação com 3150kcal.kg-1 de EMAn resultam em melhor desempenho zootécnico. A suplementação com 500 e 1000 FTU/kg nas dietas propicia melhores coeficientes de digestibilidade aparente e ileal do cálcio e do fósforo, mas influencia negativamente na deposição de cálcio, fósforo, matéria seca e cinzas das tíbias, além de afetar adversamente a quebra e a área desses ossos em frangos de corte. O comprimento do osso e os níveis de magnésio e zinco presentes nas tíbias não são influenciados pelos níveis energéticos e de fitase das dietas. Não há interação entre as diferentes densidades energéticas e as doses de fitase nas variáveis analisadas no período estudado. O aumento da densidade energética das dietas resulta em melhora na digestibilidade aparente e ileal para a maioria dos nutrientes