Study of sequential semileptonic decays of b hadrons produced at the Tevatron

We present a study of rates and kinematical properties of lepton pairs contained in central jets with transverse energy E_T > 15 GeV that are produced at the Fermilab Tevatron collider. We compare the data to a QCD prediction based on the HERWIG and QQ Monte Carlo generator programs.We find that the data are poorly described by the simulation, in which sequential semileptonic decays of single b quarks (b --> l c X with c --> l s X) are the major source of such lepton pairs.Comment: 25 pages, 8 figures. Some typos were fixed in the text and bibliography. Submitted to Phys. Rev.

Review: Insects and former foodstuffs for upgrading food waste biomasses/streams to feed ingredients for farm animals

The increasing global need to find alternative protein/energy sources has triggered research in the field of non-conventional feed ingredients, with insects and former foodstuffs being the most promising. Insects contain high level of protein and fat, whereas former foodstuffs contain high energy in the form of carbohydrates and fats; therefore, both should be considered as promising alternative feed ingredients for livestock production. In addition to the nutritional value, they also represent a way by which food waste biomasses/streams can be upgraded to valuable feed ingredients. This review outlines the main nutritional and safety issues of insects and former foodstuffs, and also considers the legal framework involved. The importance of the type of insect metamorphosis and tailored substrates that could lead to the production of a premium feed is also described. This is also the first time that a review discusses the nutritional quality of former foodstuffs. Energy and the main nutrient content of former foodstuff are compared with the composition of common cereals as the principal energy sources in animal feed. For both ingredients a critical review of the safety issues is provided. Based on the current data available, both insects and former foodstuffs have an excellent potential use as alternative feed ingredients for livestock production. When produced in line with the criteria set by major feed/food authorities, they are characterized by high quality and safety standards. This makes them comparable to other feed materials and ingredients currently available on the market, although their full nutritional, functional, safety and sustainability evaluation cannot be considered complete

Phenomenological study of the atypical heavy flavor production observed at the Fermilab Tevatron

We address known discrepancies between the heavy flavor properties of jets produced at the Tevatron collider and the prediction of conventional-QCD simulations. In this study, we entertain the possibility that these effects are real and due to new physics. We show that all anomalies can be simultaneously fitted by postulating the additional pair production of light bottom squarks with a 100% semileptonic branching fraction.Comment: 30 pages, 13 figures, 3 tables. Submitted to Phys. Rev.

Multi-muon events at the Tevatron: a hidden sector from hadronic collisions

Intrigued by some features of a small but significant fraction of the multi-muon events recently published by the CDF collaboration, we show an explicit attempt to describe them in terms of a light scalar singlet $\phi$ which communicates with the standard quarks either through a heavy scalar or a heavy fermion exchange. As suggested in arXiv:0810.7530, the singlet $\phi$ has a chain decay into a final state made of four $\tau\bar{\tau}$ pairs. We can simulate most of the muon properties of the selected sample of events. Some of these properties adhere rather well to the already published data; others should allow a decisive test of the proposed interpretation. Assuming that the test is positively passed, we show how the PAMELA excess can be fitted by the annihilation of a TeV Dark Matter particle that communicates with the Standard Model via the new light singlet(s).Comment: 19 pp, v2: small changes, agrees with the published versio

In Vitro Digestion of Chestnut and Quebracho Tannin Extracts : Antimicrobial Effect, Antioxidant Capacity and Cytomodulatory Activity in Swine Intestinal IPEC-J2 Cells

Quebracho (Qu) and chestnut (Ch) are natural sources of tannins and they are currently used in animal nutrition as feed ingredients. However, to date the bio-accessibility, antimicrobial, antioxidant, and intestinal epithelial cell stimulatory doses of Qu and Ch have not been determined. Our study investigates the antioxidant and E. coli F4+ and F18+ growth inhibitory activity of Qu, Ch, and their combinations after solubilization in water (to evaluate the already bio-accessible molecules) and after simulated gastro-intestinal digestion in vitro. The effect of an in vitro digested Ch and Qu combination was also tested on intestinal epithelial IPEC-J2 cells experimentally stressed with hydrogen peroxide (H2O2) and Dextran Sodium Sulfate (DSS). The results showed that undigested Qu and Ch alone, and in combination, exerted a valuable antioxidant capacity and E. coli F4+ and F18+ growth inhibitory activity. The concentration of 1200 \u3bcg/mL exhibited the highest E. coli growth inhibitory activity for all the samples tested. In addition, after in vitro digestion, Qu and Qu50%\u2013Ch50% maintained E. coli growth inhibitory activity and a modest antioxidant capacity. Three hours pre-treatment with in vitro digested Qu50%\u2013Ch50% counteracted the H2O2 and DSS experimentally-induced stress in the intestinal IPEC-J2 cells. Ch and Qu tannin extracts, particularly when combined, may exert E. coli F4+ and F18+ growth inhibitory activity and valuable antioxidant and cell viability modulation activities

Green tea and pomegranate extract administered during critical moments of the production cycle improves blood antiradical activity and alters cecal microbial ecology of broiler chickens

Phytobiotics are usually tested in feed and throughout the production cycle. However, it could be beneficial to evaluate their effects when administered only during critical moments, such as changes in feeding phases. The aim of the trial was to investigate the effect of a commercial plant extract (PE; IQV-10-P01, InQpharm Animal Health, Kuala Lumpur, Malaysia) on growth performance, blood antiradical activity and cecal microbiome when administered in drinking water to broiler chickens during the post-hatching phase and at each change of diet. In the experiment, 480 1-day-old male broiler chicks were assigned to two groups in a 50-day trial. Broilers received drinking water (C) or drinking water plus PE (T) at a rate of 2 mL/L on days 0 to 4, 10\u201311 and 20\u2013 21. PE did not affect performance and water intake, while total antiradical activity was improved (p < 0.05). A greater abundance of lactic acid bacteria (false discovery rate (FDR) < 0.05) was found in the T group and the result was confirmed at a lower taxonomic level with higher Lactobacillaceae abundance (FDR < 0.05). Our findings suggest that PE administration during critical moments of the production cycle of broiler chickens may exert beneficial effects at a systemic level and on gut microbial ecology