Comment on "Phonon Spectrum and Dynamical Stability of a Dilute Quantum Degenerate Bose-Fermi Mixture

We show that the conclusions of a recent PRL by Pu et al is incorrect.Comment: late

A Note on Return on Foreign Assets and Foreign Presence for UK Multinationals

Within the context of the international business literature on multinationality and performance we develop new data on the foreign presence and performance of large UK multinational enterprises (MNEs). There are 32 UK MNEs for which we can obtain data on both their degree of multinationality (measured by the ratio of foreign-to-total sales, F/T) and on their performance. Here, in addition to the traditional overall performance of the firm, shown as return on total assets (ROTA), we use new data on the return on foreign assets (ROFA). We conduct analytical work to show the positioning of the UK MNEs in the ROFA and F/T space and provide regression results showing a linear relationship between multinationality and performance, using the new ROFA metric.UK multinationals, return on foreign assets, foreign-to-total sales, performance, multinational strategy

Control of germ-band retraction in Drosophila by the zinc-finger protein HINDSIGHT

Drosophila embryos lacking hindsight gene function have a normal body plan and undergo normal germ-band extension. However, they fail to retract their germ bands. hindsight encodes a large nuclear protein of 1920 amino acids that contains fourteen C2H2-type zinc fingers, and glutamine-rich and proline-rich domains, suggesting that it functions as a transcription factor. Initial embryonic expression of hindsight RNA and protein occurs in the endoderm (midgut) and extraembryonic membrane (amnioserosa) prior to germ-band extension and continues in these tissues beyond the completion of germ-band retraction. Expression also occurs in the developing tracheal system, central and peripheral nervous systems, and the ureter of the Malpighian tubules. Strikingly, hindsight is not expressed in the epidermal ectoderm which is the tissue that undergoes the cell shape changes and movements during germ-band retraction. The embryonic midgut can be eliminated without affecting germ-band retraction. However, elimination of the amnioserosa results in the failure of germ-band retraction, implicating amnioserosal expression of hindsight as crucial for this process. Ubiquitous expression of hindsight in the early embryo rescues germ-band retraction without producing dominant gainof-function defects, suggesting that hindsight’s role in germ-band retraction is permissive rather than instructive. Previous analyses have shown that hindsight is required for maintenance of the differentiated amnioserosa (Frank, L. C. and Rushlow, C. (1996) Development 122, 1343-1352). Two classes of models are consistent with the present data. First, hindsight’s function in germ-band retraction may be limited to maintenance of the amnioserosa which then plays a physical role in the retraction process through contact with cells of the epidermal ectoderm. Second, hindsight might function both to maintain the amnioserosa and to regulate chemical signaling from the amnioserosa to the epidermal ectoderm, thus coordinating the cell shape changes and movements that drive germ-band retraction

International Success of British Companies

This paper examines the international success of British companies in a matrix combining global market share and international revenues. We identify those industry segments in which British companies are most successful internationally, and also investigate whether these are attractive industries in terms of profitability and growth. We find that the industries with the largest global market shares for British companies are Mining, Casinos (and Gaming), Oil Companies (Major), Distillers & Brewers, and Water Utilities. Four of the top ten might be considered to be “sin” industries. The industries with the highest international revenues are Precious Metals, Pharmaceuticals, Industrial (Diversified), Oil Companies (Secondary), and Mining. We also find that virtually all of the largest British firms average over a 10% global market share, in the “British Winners” segment of our matrix. However, we find the second measure, the extent of internationalization, to be ambiguous. The manufacturing (product-based) firms tried to be highly internationalized, as they compete globally, but the largest British services firms (financials, retailers) tend to have low internationalization, and therefore appear to benefit from a still somewhat regulated home market. In addition, British companies have done a good job of building up global market shares in higher growth industries. We provide recommendations for managers as to how British companies with different combinations of global market share and extent of internationalisation can improve their positions. Our methodology can also be applied to analyzing companies from other nations.

Feedback effects on the current correlations in Y-shaped conductors

We study current fluctuations in a Y-shaped conductor connected to external leads with finite impedances. We show that, due to voltage fluctuations in the circuit, the moments of the transferred charges cannot be obtained from simple rescaling of the bare values already in the second moments. The cross-correlation between the output terminals can change from negative to positive under certain parameter regimes.Comment: 4 pages, figures attached separatel