Top Quark Spin Correlations at the Tevatron

Recent measurements of the correlation between the spin of the top and the spin of the anti-top quark produced in proton anti-proton scattering at a centre of mass energy of 1.96 TeV by the CDF and D0 collaborations are discussed. Using up to 4.3 fb^-1 of data taken with the CDF and D0 detectors the spin correlation parameter C, the degree to which the spins are correlated, is measured in dileptonic and semileptonic final states. The measurements are found to be in agreement with Standard Model predictions.Comment: 8 pages, 5 figures, talk presented at TOP2010, Bruges, Belgiu

Open science software development

This presentation was part of Day 4 of the Open Science in Practice Summer School #osip2017. Additional information can be found on osip2017.epfl.ch

Strategic Fit of Supply Chain Management Information Systems: A Measurement Model

This study expands upon current conceptualizations of fit between a firm’s competitive strategies and infor- mation systems capabilities. Limitations of existing theories have hindered the development of operationalized models for measuring the strategic fit of a firm’s information system. Using configurational theory and the concept of emergent strategies and capabilities, this paper develops a model for measuring the strategic fit of a specific type of information system: supply chain management information systems (SCM IS). Findings from a multiple-case study of five manufacturers indicate the developed model can give an accurate, reliable, and useful analysis of the strategic fit of a firm’s SCM IS. The operationalized model is sufficiently grounded theoretically and empirically to enable further study of the strategic fit of IS and its relationship with firm performance

Quantum Chemical Modeling of Pressure-Induced Spin Crossover in Octahedral Metal-Ligand Complexes.

Spin state switching on external stimuli is a phenomenon with wide applicability, ranging from molecular electronics to gas activation in nanoporous frameworks. Here, we model the spin crossover as a function of the hydrostatic pressure in octahedrally coordinated transition metal centers by applying a field of effective nuclear forces that compress the molecule towards its centroid. For spin crossover in first-row transition metals coordinated by hydrogen, nitrogen, and carbon monoxide, we find the pressure required for spin transition to be a function of the ligand position in the spectrochemical sequence. While pressures on the order of 1 GPa are required to flip spins in homogeneously ligated octahedral sites, we demonstrate a fivefold decrease in spin transition pressure for the archetypal strong field ligand carbon monoxide in octahedrally coordinated Fe2+ in [Fe(II)(NH3 )5 CO]2+

Pitfalls of evaluating a classifier’s performance in high energy physics applications

<p>Pitfalls of evaluating a classifier's performance in high energy physics applications.</p> <p>- Presented at the ALEPH workshop, NIPS, December 2015.</p> <p>- Notebook available at https://github.com/glouppe/talk-aleph-workshop2015/blob/master/notebook-pitfalls.ipynb</p

Ten simple rules for writing Dockerfiles for reproducible data science.

Computational science has been greatly improved by the use of containers for packaging software and data dependencies. In a scholarly context, the main drivers for using these containers are transparency and support of reproducibility; in turn, a workflow's reproducibility can be greatly affected by the choices that are made with respect to building containers. In many cases, the build process for the container's image is created from instructions provided in a Dockerfile format. In support of this approach, we present a set of rules to help researchers write understandable Dockerfiles for typical data science workflows. By following the rules in this article, researchers can create containers suitable for sharing with fellow scientists, for including in scholarly communication such as education or scientific papers, and for effective and sustainable personal workflows

Targeting Glycosylation Pathways and the Cell Cycle: Sugar-Dependent Activity of Butyrate-Carbohydrate Cancer Prodrugs

SummaryShort-chain fatty acid (SCFA)-carbohydrate hybrid molecules that target both histone deacetylation and glycosylation pathways to achieve sugar-dependent activity against cancer cells are described in this article. Specifically, n-butyrate esters of N-acetyl-d-mannosamine (But4ManNAc, 1) induced apoptosis, whereas corresponding N-acetyl-d-glucosamine (But4GlcNAc, 2), d-mannose (But5Man, 3), or glycerol (tributryin, 4) derivatives only provided transient cell cycle arrest. Western blots, reporter gene assays, and cell cycle analysis established that n-butyrate, when delivered to cells via any carbohydrate scaffold, functioned as a histone deacetylase inhibitor (HDACi), upregulated p21WAF1/Cip1 expression, and inhibited proliferation. However, only 1, a compound that primed sialic acid biosynthesis and modulated the expression of a different set of genes compared to 3, ultimately killed the cells. These results demonstrate that the biological activity of butyrate can be tuned by sugars to improve its anticancer properties