Transverse mass distributions of strange particles produced in Pb-Pb collisions at 158 A GeV/c

Experiment NA57 has collected high statistics, high purity samples of $K^0_s$, $\Lambda$, $\Xi$ and $\Omega$ produced in Pb-Pb collisions at 158 $A$ GeV/$c$. In this paper we present a study of the transverse mass spectra of these particles for a sample of events corresponding to about the most central 55% of the inelastic Pb-Pb cross section. We analyse the transverse mass distributions in the framework of the blast-wave model for the full sample under consideration and, for the first time at the SPS, as a function of the event centrality.Comment: Contribution to the International Workshop on QCD: QCD@Work 2003 - Conversano (Italy) 14-18 June 2003 (eConf C030614

Consequences of Vertical Separation and Monopoly: Evidence from the Telecom Privatizations

Two common policy instruments used by governments around the world to increase the availability of basic telephony (i.e., local, long distance, and international service) have been: (1) award monopoly rights on basic services to cross-subsidize residential local telephony; and (2) separate vertically (i.e., structural separation) the owner of the local fixed network from the provider of long distance or international telephone services. I use data from a panel of 67 countries during the seven years following the privatization of the telephone monopoly and find that contrary to wide spread beliefs: (1) monopoly on basic services is not associated with lower residential telephony prices; quite the opposite, monopoly increases residential local prices; (2) monopoly does not help universal service provision and lowers the use of international telephony; and (3) mandatory vertical separation reduces international telephony usage and the number of fixed lines in service. In summary, monopoly and vertical separation harm those consumers that were precisely designed to help: the downstream (business) users of international telephony and the upstream users of residential local telephony.

Non-Decreasing Sequences

Non-decreasing sequences are a generalization of binary covering arrays, which has made research on non-decreasing sequences important in both math and computer science. A non-decreasing sequence of subsets of a finite set S of size s, {S1, S2,.... St}, length t, and strength d, is a sequence of non-empty subsets where the union of any d previous subsets in the sequence does not contain any subsequent subset. The goal of this research is to find properties of these non-decreasing sequences as the variables d, s, and t change. We also explored methods for creating a maximum length for a non-decreasing sequence given d and s. Through our research, we discovered and proved basic properties of these non-decreasing sequences. In addition to this, we can describe a method we used while trying to find the maximum length of a sequence. In the future, research can be conducted to find an exact formula that will generate a maximum length sequence given a non-decreasing sequence of strength d

Above-room-temperature ferromagnetism in half-metallic Heusler compounds NiCrP, NiCrSe, NiCrTe and NiVAs: A first-principles study

We study the interatomic exchange interactions and Curie temperatures in half-metallic semi Heusler compounds NiCrZ (Z=P, Se, Te) and NiVAs. The study is performed within the framework of density functional theory. The calculation of exchange parameters is based on the frozen-magnon approach. It is shown that the exchange interactions in NiCrZ vary strongly depending on the Z constituent. The Curie temperature, Tc, is calculated within the mean field and random phase approximations. The difference between two estimations is related to the properties of the exchange interactions. The predicted Curie temperatures of all four systems are considerably higher than room temperature. The relation between the half-metallicity and the value of the Curie temperature is discussed. The combination of a high spin-polarization of charge carriers and a high Curie temperature makes these Heusler alloys interesting candidates for spintronics applications.Comment: 6 pages, 3 figure

Profiling Consumer Trend-setters in the Canadian Healthy-foods Market

The agri-food industry faces new challenges as consumer demand for new, healthier foods increases. Media headlines frequently mention health benefits from certain foods and food components, and consumers are more health conscious because they are aging. They realize their food choices can reduce their risk of developing chronic illnesses such as cancer and heart disease. The competitive advantages for firms who are the first to bring their food innovations to market will depend in part on the efficacy of their marketing strategies. Firms that can identify and target those consumers who are most interested in trying new foods with enhanced functional health properties will likely be the most successful. This paper identifies attitudinal and sociodemographic characteristics that influence a consumer’s desire to be among the first to try innovative functional foods.Consumer/Household Economics, Health Economics and Policy, Marketing,