From First Lyapunov Coefficients to Maximal Canards

Hopf bifurcations in fast-slow systems of ordinary differential equations can be associated with surprising rapid growth of periodic orbits. This process is referred to as canard explosion. The key step in locating a canard explosion is to calculate the location of a special trajectory, called a maximal canard, in parameter space. A first-order asymptotic expansion of this location was found by Krupa and Szmolyan in the framework of a "canard point"-normal-form for systems with one fast and one slow variable. We show how to compute the coefficient in this expansion using the first Lyapunov coefficient at the Hopf bifurcation thereby avoiding use of this normal form. Our results connect the theory of canard explosions with existing numerical software, enabling easier calculations of where canard explosions occur.Comment: preprint version - for final version see journal referenc

First measurement of interference fragmentation on a transversely polarized hydrogen target

The HERMES experiment has measured for the first time single target-spin asymmetries in semi-inclusive two-pion production using a transversely polarized hydrogen target. These asymmetries are related to the product of two unknowns, the transversity distribution function and the interference fragmentation function. In the invariant mass range 0.51 GeV < M_inv < 0.97 GeV the measured asymmetry deviates significantly from zero, indicating that two-pion semi-inclusive deep-inelastic scattering can be used to probe transversity.Comment: 6 pages, 6 figures, contribution to the proceedings of the International Workshop on Transverse Polarisation Phenomena in Hard Processes (Transversity 2005), Como, Italy, Sep 7 - 10, 200

WASH coalition building guidelines

The Water Supply and Sanitation Collaborative Council (WSSCC) is an international membership organisation that has worked, since 1990, to achieve sustainable water supply and sanitation for all people, through enhancing collaboration among sector agencies and professionals. As part of its activities within two of its programme areas – Networking & Knowledge Management, and Advocacy & Communications – WSSCC encourages the development of national water supply, sanitation and hygiene (WASH) Coalitions. The role of WASH Coalitions ranges from information sharing to the advocacy of specific policy changes, but they universally address a felt need for improved systematic communication, collaboration and joint action among the sector players in a certain country. As a vehicle for awareness raising and advocacy, most national WASH Coalitions have developed national WASH Campaigns. A special role is given to the National Coordinators, who are expected to maintain the links with the WSSCC Secretariat, exercise quality control and practise a degree of coordination and facilitation of the coalition. However, coalitions, like partnerships, are complicated organisms and some of the existing WASH Coalitions have had only limited impact and varying degrees of success. This is partly due to the complexity of building a successful coalition that responds to the specific needs of the country in which it is created, and partly due to the undefined or open mandate of the WASH Coalitions, resulting in a lack of clarity about what they are intended to do

Two-hadron single target-spin asymmetries: first measurement by HERMES

Single target-spin asymmetries in semi-inclusive two-pion production were measured for the first time by the HERMES experiment, using a longitudinally polarized deuterium target. These asymmetries relate to the unknown transversity distribution function $h_1(x)$ through, also unknown, interference fragmentation functions. The presented results are compared with a model for the dependence of one of these interference fragmentation functions on the invariant mass of the pion pair.Comment: 4 pages, 4 figures, contribution to the proceedings for the 16th international spin physics symposium (SPIN'2004

Analyzing female labor supply: Evidence from a Dutch tax reform

This paper uses the exogenous variation caused by the Dutch tax reform of 2001 to investigate how married women react to financial incentives. Among OECD countries, the Netherlands has average female labor force participation, but by far the highest rate of part-time work. Our main conclusion is that the positive significant effect of the 2001 tax reform on labor force participation dominates the negative insignificant effect on working hours. Our preferred explanation is that women respond more to changes in tax allowances than to changes in marginal tax rates.

The Horseshoe Estimator: Posterior Concentration around Nearly Black Vectors

We consider the horseshoe estimator due to Carvalho, Polson and Scott (2010) for the multivariate normal mean model in the situation that the mean vector is sparse in the nearly black sense. We assume the frequentist framework where the data is generated according to a fixed mean vector. We show that if the number of nonzero parameters of the mean vector is known, the horseshoe estimator attains the minimax $\ell_2$ risk, possibly up to a multiplicative constant. We provide conditions under which the horseshoe estimator combined with an empirical Bayes estimate of the number of nonzero means still yields the minimax risk. We furthermore prove an upper bound on the rate of contraction of the posterior distribution around the horseshoe estimator, and a lower bound on the posterior variance. These bounds indicate that the posterior distribution of the horseshoe prior may be more informative than that of other one-component priors, including the Lasso.Comment: This version differs from the final published version in pagination and typographical detail; Available at http://projecteuclid.org/euclid.ejs/141813426

Guide to the Linfield College Photograph Collection

This collection contains photographs, glass lantern and plastic slides, and film negatives depicting the many-layered facets of life at Linfield College on its McMinnville and Portland campuses. The photography features (without limit to): students, faculty and staff, commencements, guest speakers and performers, buildings, activities and clubs, athletics, the arts (studio and performance), residence life, social, and study scenes

Updates in metabolomics tools and resources: 2014-2015

Data processing and interpretation represent the most challenging and time-consuming steps in high-throughput metabolomic experiments, regardless of the analytical platforms (MS or NMR spectroscopy based) used for data acquisition. Improved machinery in metabolomics generates increasingly complex datasets that create the need for more and better processing and analysis software and in silico approaches to understand the resulting data. However, a comprehensive source of information describing the utility of the most recently developed and released metabolomics resources—in the form of tools, software, and databases—is currently lacking. Thus, here we provide an overview of freely-available, and open-source, tools, algorithms, and frameworks to make both upcoming and established metabolomics researchers aware of the recent developments in an attempt to advance and facilitate data processing workflows in their metabolomics research. The major topics include tools and researches for data processing, data annotation, and data visualization in MS and NMR-based metabolomics. Most in this review described tools are dedicated to untargeted metabolomics workflows; however, some more specialist tools are described as well. All tools and resources described including their analytical and computational platform dependencies are summarized in an overview Table

Structure and Strategy, How Do They Match in the Netherlands?

Farm organization, and the balance between the household and the farm have changed. This paper explores the relation between the organizational form and strategy of Dutch farmers and shows that strategy and structure are related. Legal persons and partnerships with multiple households can be especially found among the farmers focusing on economies of scale. One-man businesses and the one household partnerships more often show diversification strategies. One-man businesses are relatively more encountered amongst the life style farmers, whilst one household partnerships are stronger present amongst rural entrepreneurs.family farm, household, legal form, strategy, typology, Farm Management,

Labour-market in a border-area; searching for jobs and the influence of borders

At the moment borders, border-related problems, and the process of tearing down borders are very much in the centre of interest. Especially in Europe a lot of scientific work is done with regard to borders of countries, to determine their role in the ongoing integration process. In this respect border-regions are considered to be able to play a catalytic role. The borderland economies on both sides of a national border in this view have to be changed into one transborder economy. Initiatives to encourage cross-border integration however are not always successful. To our opinion, one of the main reasons lies in the fact that the border has many faces. The effect of a border differs, depending on the type of interaction (e.g. economic, social-cultural or institutional) and the nature of the region it defines. This paper tries to formulate a conceptual framework, within which the different properties of borders and border-regions are taken into account. Next this model is applied to the regional labour-market in the Nijmegen-Arnhem border-area in the eastern part of the Netherlands. The most important questions to be answered are: - Are there effects stemming from the fact the regional labour-market in the Arnhem-Nijmegen is part of a (peripheral) borderland economy? - What are the effects of the border with regard to the interaction of the region Arnhem-Nijmegen with the neighbouring region in Germany? - Is a part of the "natural" labour-market cut off by the national border, or put in other words, what would happen if the Dutch-German border would disappear completely? Keywords: Borders, Regional labour-markets, Transition