The light elements in the light of 3D and non-LTE effects

In this review we discuss possible systematic errors inherent in classical 1D LTE abundance analyses of late-type stars for the light elements (here: H, He, Li, Be and B). The advent of realistic 3D hydrodynamical model atmospheres and the availability of non-LTE line formation codes place the stellar analyses on a much firmer footing and indeed drastically modify the astrophysical interpretations in many cases, especially at low metallicities. For the Teff-sensitive hydrogen lines both stellar granulation and non-LTE are likely important but the combination of the two has not yet been fully explored. A fortuitous near-cancellation of significant but opposite 3D and non-LTE effects leaves the derived 7Li abundances largely unaffected but new atomic collisional data should be taken into account. We also discuss the impact on 3D non-LTE line formation on the estimated lithium isotopic abundances in halo stars in light of recent claims that convective line asymmetries can mimic the presence of 6Li. While Be only have relatively minor non-LTE abundance corrections, B is sensitive even if the latest calculations imply smaller non-LTE effects than previously thought.Comment: 10 pages, invited review for IAU Symposium 268 "Light elements in the Universe", C. Charbonnel, M. Tosi, F. Primas, C. Chiappini (editors

Food Reserve Stocks and Critical Food Shortages - a Proposal Based on the Needs of Sub-Saharan Africa

This working paper examines the food security policy, where food security means ensuring an adequate supply of food for hungry people. In particular, the recommendations of FAO are being used as a measuring rod against which food security policies are assessed. By means of FAO's database a statistical analysis of all Sub-Saharan Africa countries with respect to measuring the incidence and severity of critical food shortages are carried out. Stock policies seem to have been the answer when issues of ensuring adequate supplies have surfaced. In the paper, an estimate of the costs of keeping stocks is provided, and the costs are quite staggering. Based on the statistical analysis an estimate of the number and volume of acute food shortages per year in Sub-Saharan Africa is achieved. Upon this number a much cheaper alternative to keeping stocks for security purposes is proposed. It is proposed that a financial fund is set up with the sole purpose of purchasing grains on the open market when acute food shortages occur. In order for the fund to achieve its goals it must be completely independent of politics, and the financing and replenishing of the fund must be automatic. The advantages are that a lot of costs are saved which could be used to improve food security policies in developing countries. Furthermore, the supply of food aid is done via a global fund, and is not the result of political considerations in donor (big exporting) countries. The reservations voiced by some developing countries that further liberalisations in agricultural policies in the WTO round of negotiations could jeopardise food security is answered by this fund. Liberalisations of agricultural policies may lead to lower food stocks in the big exporting countries, but the proposed financial fund does not rely on such stocks. It is found that the purchases the fund would have to conduct only comprise a small fraction of the world trade in cereals.Food, stocks, shortages, uncertainty, Sub-Saharan Africa, Food Security and Poverty,

Some remarks related to the density of {(bn(modn))/n:n∈N}\{(b^n\pmod n)/n:n\in\mathbb{N}\}

For $b\in\mathbb{N}, b\ge2$ we determine the limit points of certain subsets of $$\left\{\frac{b^n\pmod{n}}{n}:n\in\mathbb{N}\right\}.$$ As a consequence, we obtain the density of the latter set in $[0,1]$, a result first established in 2013 by Cilleruelo, Kumchev, Luca, Ru\'{e} and Shparlinski.

Information-Sharing and Strategy by Food Industry Firms

This study investigates the strategic behaviour of food industry firms. Its two goals are to: (i) characterise strategies being employed; and (ii) identify distinct approaches to information-sharing Data from an interview-format survey of Danish food industry firms are used to characterise strategy at two levels: 11 “strategic orientations”; each of which is composed of 3-6 of a total 57 “strategic actions”. Principal components were identified and two complementary cluster analysis techniques were used to assemble clusters that are composed of firms either with distinct strategies, or sets of strategies occurring in distinct combinations. Eight clusters emerge, with reasonable procedural performance. The clusters are distinct in a surprisingly large number of ways, including their strategies for market share, pricing, approach and response to regulation, exports and use of retailers’ own-label brands. Information-sharing strategies are closely linked to both marketing strategy and regulation response/anticipation. Individual clusters identify distinct sets of behaviour regarding information-sharing up and/or down the value chain, their approach to quality and other aspects of market segmentation, targeting of export markets, and willingness to compete on price. Clusters’ distinct strategies regarding regulation featured anticipation, as opposed to several diverse means of passing on compliance costs: to buyers or to sellers. Such activities were linked to information-sharing strategies in different ways by different clusters.Agribusiness, Agricultural and Food Policy, Farm Management, Food Consumption/Nutrition/Food Safety, Industrial Organization,