Motion in Brane World Models: The Bazanski Approach

Recently, path equations have been obtained for charged, spinning objects in brane world models, using a modified Bazanski Lagrangian. In this study, path deviation equations of extended objects are derived. The significance of moving extended objects in brane world models is examined. Motion in non- symmetric brane world models is also considered.Comment: A paper presented at the Thirteenth International Symposium on Particles, Strings and Cosmology PASCOS-07, held in London, 2-7 July 200

A Symbolical Approach to Negative Numbers

Recent Early Algebra research indicates that it is better to teach negative numbers symbolically, as uncompleted subtractions or “difference pairs”, an idea due to Hamilton, rather than abstractly as they are currently taught, since all the properties of negative numbers then follow from properties of the subtraction operation with which children are already familiar. Symbolical algebra peaked in the 19th Century, but was superseded by abstract algebra in the 20th Century, because Peacock’s permanence principle, which asserted that solutions obtained symbolically would actually be correct, remained unproven. The main aim of this paper is to provide this missing proof, in order to place difference pairs on a rigorous mathematical foundation, so that they may for the first time be the subject of modern classroom based research. The essential ingredient in this proof is a new physical model, called the banking model, a development of the hills and dales model used in schools in New Zealand, which besides improving upon current models in several respects, has the crucial advantage of being a true physical model, that is, the properties of negative numbers come from freely manipulating the model in the manner of a sandbox, not by following an abstract set of rules. Throughout this paper a close correspondence is drawn between negative numbers viewed as uncompleted subtractions and fractions viewed as uncompleted divisions, which suggests a practical notation for difference pairs as single numbers but whose digits are either positive or negative, the equivalent for integers of the decimal fraction notation for rationals. The banking model is the ideal tool for visualising such positive and negative digits, and examples are provided to show not only that this is a powerful notation for use at Secondary level, but also that it resolves some long-standing problems of the subtraction algorithm at Primary level

Assessment of heavy metal pollution in a columbite/tantalite mining site in Edege-Mbeki, North Central Nigeria

The release of pollutants due to mining activities, especially tailings, has negative consequences on soil and affects agricultural productivity. This study details the assessment of metals (Ni, Mn, Pb, Cd and Fe), physicochemical parameters of the soil and how they affect metal bioavailability and biotoxicity. Metal concentrations were determined using Atomic Absorption Spectrophotometer (AA-6800 Shimadzu). The results of the analysis show that the mean pH varied from a minimum of 7.12±0.36 to a maximum of 7.60±0.28 across all the study area and sampling points. The percent organic matter had an average minimum value of 0.13±0.08% and a maximum value of 0.82±0.32% in the study area. The heavy metal analysis result shows that concentrations in all the soil and sediments of the study area were all below the maximum permissible limit. Mean concentrations of Ni, Mn, Cd, Pb and Fe had minimum values of 1.45±0.56, 43.3±0.43, 1.11±0.22, 5.50±0.28 and 522±0.88 mg/kg respectively, and the mean maximum concentrations had values of 11.70±0.90, 200±0.17, 20.7±0.11, 31.0±0.78 and 2716±0.83 mg/kg respectively. The findings show no metal contamination. However, the enrichment factor and contamination factor revealed that the presence of Ni, Mn, Cd and Cd in soil samples of the study area may be due to anthropogenic activities of mining.Keywords: Heavy metals, Edge-Mbeki, Physiochemical, Contaminatio

Cardiac Multidetector Computed Tomography: Basic Physics of Image Acquisition and Clinical Applications

Cardiac MDCT is here to stay. And, it is more than just imaging coronary arteries. Understanding the differences in and the benefits of one CT scanner from another will help you to optimize the capabilities of the scanner, but requires a basic understanding of the MDCT imaging physics

Neutron stars and the fermionic Casimir effect

The inner crust of neutron stars consists of nuclei of various shapes immersed in a neutron gas and stabilized by the Coulomb interaction in the form of a crystal lattice. The scattering of neutrons on nuclear inhomegeneities leads to the quantum correction to the total energy of the system. This correction resembles the Casimir energy and turns out to have a large influence on the structure of the crust.Comment: 6 pages, 1 figure, presented at the Fifth Workshop on Quantum Field Theory under the Influence of External Conditions, Leipzig, Germany, September 10-15, 2001, to appear in Int. J. Mod. Phys.

Viv\u27 le roi : chansonnette

Le gros major me l\u27as dit; t\u27estropp\u27tit qui m\u27a dit; t\u27estropp\u27 tit qui m\u27adit, pourêtr\u27 militaireAh! qué bonheur sur ma foi! y paraît, que sans moi, onpeut fair\u27la guerre très animé et avec une joie croissante.Viv\u27 le Roi, viv\u27 le Roi et viv\u27 le Roi quin\u27 veut point d\u27moi! viv\u27 le Roi! viv\u27 le Roi! le Roi n\u27veut point d\u27moi!.... N, i, ni, tout est fini; je n\u27 pars point pour la milice, merci, gros major, merci, faut tout d\u27 mêm que j\u27te bénisse; moi qui n\u27pouvais pu dormir tant que j\u27eraignais l\u27exercice, en m\u27empêchant\u27 de servir, tu m\u27rends un la meux service. Mev\u27 là tout seul dans l\u27pays,Pour moi c\u27est tout avantage,Les amissont tous partis, Je deviens l\u27coq duvillage.Quand viendra la fêt\u27 des Rois jn\u27anrai qu\u27a choisir ma Reine quantà moi jen\u27 crains pul\u27 choixPour Roi faudra bien qu\u27on m\u27prenne. Jean Pichet quis\u27 gaussait d\u27 moin\u27 apoint z\u27eu z\u27unbrind\u27 ma chance,Y s\u27en va servir le Roi Dans tous les pays d\u27la France; moi j\u27y dis: mon: Jean PichetTe v\u27là mort! oùe\u27 est tont comme, Toi quit\u27 trouvais si ben fait! V\u27lac\u27 que c\u27est que dêtr bel homme!... A la fêted\u27 not endroitC\u27est moi qui son n\u27ra les cloches,C\u27est à moi quer\u27 viendra l\u27droitDêtr\u27 parrain de tous les miochesPour arriver au pouvoirPas besoin dêtr\u27 militaire,En m\u27 mariant j\u27aurai l\u27espoirDêtr un beanjour pèreet très gaiment. maire!...Merci, gros major, merci, tu l\u27as dit:J\u27suis tropp\u27tit, j\u27suis tropp\u27tit, tu l\u27as dit pour êtr\u27 militaire!...Ici j\u27menvas vivr\u27 henreux ben heureux, ben joyeux, à l\u27abri avec joieet f\u27ort. de l\u27enn\u27 mi, et d\u27larmé\u27 d\u27la guerre!...Viv\u27 le Roi! viv\u27 le Roi et viv\u27 le Roi qui n\u27veut point d\u27moi! viv\u27 le Roi! viv\u27 le Roi! le Roi n\u27veut pas d\u27moi. Viv\u27 le Roi!..

Optimization Approaches for the Traveling Salesman Problem with Drone

The fast and cost-efficient home delivery of goods ordered online is logistically challenging. Many companies are looking for new ways to cross the last-mile to their customers. One technology-enabled opportunity that recently has rec

Asymptotic Expansions for lambda_d of the Dimer and Monomer-Dimer Problems

In the past few years we have derived asymptotic expansions for lambda_d of the dimer problem and lambda_d(p) of the monomer-dimer problem. The many expansions so far computed are collected herein. We shine a light on results in two dimensions inspired by the work of M. E. Fisher. Much of the work reported here was joint with Shmuel Friedland.Comment: 4 page

Hepatic effects of tartrazine (E 102) after systemic exposure are independent of oestrogen receptor interactions in the mouse

Tartrazine is a food colour that activates the transcriptional function of the human oestrogen receptor alpha in an in vitro cell model. Since oestrogens are cholestatic, we hypothesised tartrazine will cause periportal injury to the liver in vivo. To test this hypothesis, tartrazine was initially administered systemically to mice resulting in a periportal recruitment of inflammatory cells, increased serum alkaline phosphatase activity and mild periportal fibrosis. To determine whether an oestrogenic effect may be a key event in this response, tartrazine, sulphonated metabolites and a food additive contaminant were screened for their ability to interact with murine oestrogen receptors. In all cases, there were no interactions as agonists or antagonists and further, no oestrogenicity was observed with tartrazine in an in vivo uterine growth assay. To examine the relevance of the hepatic effects of tartrazine to its use as a food additive, tartrazine was orally administered to transgenic NF-κB-Luc mice. Pre- and concurrent oral treatment with alcohol was incorporated given its potential to promote gut permeability and hepatic inflammation. Tartrazine alone induced NF- κB activities in the colon and liver but there was no periportal recruitment of inflammatory cells or fibrosis. Tartrazine, its sulphonated metabolites and the contaminant inhibited sulphotransferase activities in murine hepatic S9 extracts. Given the role of sulfotransferases in bile acid excretion, the initiating event giving rise to periportal inflammation and subsequent hepatic pathology through systemic tartrazine exposure is therefore potentially associated an inhibition of bile acid sulphation and excretion and not on oestrogen receptor-mediated transcriptional function. However, these effects were restricted to systemic exposures to tartrazine and did not occur to any significant effect after oral exposure

Prevalence of Non-O157:H7 Shiga Toxin-Producing \u3ci\u3eEscherichia coli\u3c/i\u3e in Diarrheal Stool Samples from Nebraska

We determined the prevalence of Shiga toxin-producing Escherichia coli (STEC) in diarrheal stool samples from Nebraska by three methods: cefixime-tellurite sorbitol MacConkey (CT-SMAC) culture, enterohemorrhagic E. coli (EHEC) enzyme immunoassay, and stx1,2 polymerase chain reaction (PCR). Fourteen (4.2%) of 335 specimens were positive by at least one method (CT-SMAC culture [6 of 14], EHEC enzyme immunoassay [13 of 14], stx1,2 PCR [14 of 14]). Six contained serogroup 0157, while non-0157 were as prevalent as 0157 serogroups