Some Spectral and Quasi-Spectral Characterizations of Distance-Regular Graphs

In this paper we consider the concept of preintersection numbers of a graph. These numbers are determined by the spectrum of the adjacency matrix of the graph, and generalize the intersection numbers of a distance-regular graph. By using the preintersection numbers we give some new spectral and quasi-spectral characterizations of distance-regularity, in particular for graphs with large girth or large odd-girth

Enumeration of cospectral and coinvariant graphs

We present enumeration results on the number of connected graphs up to 10 vertices for which there is at least one other graph with the same spectrum (a cospectral mate), or at least one other graph with the same Smith normal form (coinvariant mate) with respect to several matrices associated to a graph. The present data give some indication that possibly the Smith normal form of the distance Laplacian and the signless distance Laplacian matrices could be a finer invariant to distinguish graphs in cases where other algebraic invariants, such as those derived from the spectrum, fail. Finally, we show a new graph characterization using the Smith normal form of the signless distance Laplacian matrix

Ciprofloxacin and Compulsory Licensing of Pharmaceutical Patents

The recent threat of biological terrorism involving the Anthrax virus incited a debate about whether the United States government should use its powers under 28 USC §1498 to take a compulsory license on the drug ciprofloxacin in order to stockpile it. Negotiating a deal with Bayer allowed the United States to stockpile ciprofloxacin at a substantial discount while avoiding the negative consequences of issuing a compulsory license. Under 35 U.S.C. 1498, the United States government has the authority to issue a compulsory license; however, the government may not have the authority under the TRIPs agreement. In fact, under the interpretation of the TRIPs agreement that the United States has adopted in previous situations when other countries wanted to issue compulsory licenses on pharmaceuticals, the United States most likely would have violated TRIPs if it had issued a compulsory license for ciprofloxacin. Furthermore, the policy decision to have strong patent protection and to not have price controls on pharmaceuticals in the United States has led to the development of a very strong pharmaceutical industry that leads the world in the development of innovative drugs

Joint use of attribute importance rankings and non-attendance data in choice experiments

The joint and alternative uses of attribute non-attendance and importance ranking data within discrete choice experiments are investigated using data from Lebanon examining consumers’ preferences for safety certification in food. We find that both types of information; attribute non-attendance and importance rankings, improve estimates of respondent utility. We introduce a method of integrating both types of information simultaneously and find that this outperforms models where either importance ranking or non-attendance data are used alone. As in previous studies, stated non-attendance of attributes was not found to be consistent with respondents having zero marginal utility for those attribute

The inverse nullity pair problem and the strong nullity interlacing property

The inverse eigenvalue problem studies the possible spectra among matrices whose off-diagonal entries have their zero-nonzero patterns described by the adjacency of a graph $G$. In this paper, we refer to the $i$-nullity pair of a matrix $A$ as $(\operatorname{null}(A), \operatorname{null}(A(i))$, where $A(i)$ is the matrix obtained from $A$ by removing the $i$-th row and column. The inverse $i$-nullity pair problem is considered for complete graphs, cycles, and trees. The strong nullity interlacing property is introduced, and the corresponding supergraph lemma and decontraction lemma are developed as new tools for constructing matrices with a given nullity pair

Can Europe recover without credit?

Data from 135 countries covering five decades suggests that creditless recoveries, in which the stock of real credit does not return to the pre-crisis level for three years after the GDP trough, are not rare and are characterised by remarkable real GDP growth rates: 4.7 percent per year in middle-income countries and 3.2 percent per year in high-income countries. However, the implications of these historical episodes for the current European situation are limited, for two main reasons. First, creditless recoveries are much less common in highincome countries, than in low-income countries which are financially undeveloped. European economies heavily depend on bank loans and research suggests that loan supply played a major role in the recent weak credit performance of Europe. There are reasons to believe that, despite various efforts, normal lending has not yet been restored. Limited loan supply could be disruptive for the European economic recovery and there has been only a minor substitution of bank loans with debt securities. Second, creditless recoveries were associated with significant real exchange rate depreciation, which has hardly occurred so far in most of Europe. This stylised fact suggests that it might be difficult to re-establish economic growth in the absence of sizeable real exchange rate depreciation, if credit growth does not return

The influence of religion and religiosity on food waste generation among restaurant clienteles

Introduction: Food waste is a global issue of primary concern due to its repercussions on the environment, food security, and the economy. Our study aimed to explore the impact of religion and religiosity on food waste generation among restaurant clienteles in Lebanon, a religiously diverse country. Methods: A convenient sample of 927 restaurant patrons dining out in Greater Beirut was interviewed face-to-face, and leftovers at each table were collected and weighed. Results: Christian diners were found to waste significantly less (p < 0.05) than Druze and Muslim patrons in restaurants serving Lebanese and non-Lebanese food. Individuals (19.1% of respondents) from both religions who reported that their relationship with God is the priority in life waste similarly compared to those who claimed to have other priorities. The higher the religiosity score among both Christians and Muslims/Druze groups was, the lower the food waste quantity got, highlighting the reduced wasteful behavior among highly religious people. Discussion: Based on these findings, including religious cues in consumer-based interventions to reduce food waste can be more effective. This can be achieved through marketing campaigns that communicate religious-based messages to trigger religious beliefs that reduce food waste, using physical spaces and rituals of mosques and churches