Splitters and Decomposers for Binary Matroids

Let $EX[M_1\dots, M_k]$ denote the class of binary matroids with no minors isomorphic to $M_1, \dots, M_k$. In this paper we give a decomposition theorem for $EX[S_{10}, S_{10}^*]$, where $S_{10}$ is a certain 10-element rank-4 matroid. As corollaries we obtain decomposition theorems for the classes obtained by excluding the Kuratowski graphs $EX[M(K_{3,3}), M^*(K_{3,3}), M(K_5), M^*(K_5)]$ and $EX[M(K_{3,3}), M^*(K_{3,3})]$. These decomposition theorems imply results on internally $4$-connected matroids by Zhou [\ref{Zhou2004}], Qin and Zhou [\ref{Qin2004}], and Mayhew, Royle and Whitte [\ref{Mayhewsubmitted}].Comment: arXiv admin note: text overlap with arXiv:1403.775

Reactivation of ethanol-calcium-isolated cilia from Tetrahymena pyriformis

Cilia isolated from Tetrahymena after ciliary shedding is induced by the addition of CaCl2 or other salts to cells suspended in an ethanol solution (4, 6, 11) have been studied chemically and enzymatically (4, 6, 11, 12, 13), but until now have never been shown to be capable of motility in the presence of ATP. In contrast to this, Gibbons (7) has demonstrated the reactivation of glycerol-isolated cilia by techniques similar to those developed for grasshopper sperm tails (8) and Polytoma flagella (2). However, the glycerol technique is much less satisfactory than the ethanol-calcium method for isolating pure cilia. This paper describes the reactivation, which can be obtained with ATP or ADP, of cilia isolated by an ethanol-calcium method (6), followed by glycerination or other treatments

Clark W. Beasley (1942–2012)

Mcinnes, Sandra J. (2013): Clark W. Beasley (1942-2012). Zootaxa 3652 (4): 497-500, DOI: http://dx.doi.org/10.11646/zootaxa.3652.4.

Did Jesus Exclude Women from Priesthood?

This sentence purports to give the principle upon which the fundamental affirmation of the Declaration rests, namely, the Sacred Congregation for the Doctrine of the Faith judges it necessary to recall that the Church , in fidelity to the example of the Lord, does not consider herself authorized to admit women to priestly ordination 1 (emphasis mine). Section 4 of the Declaration, and specifically the sentence being commented upon here, maintains that the reason why the Church is not only unwilling at this time to ordain women but is now, and will always remain, unable to ordain women to the priesthood is that Jesus acted in some way during his earthly life which divinely established the priesthood as exclusively male. This assertion raises two serious questions, one of theory and one of fact

Reducing the fine-tuning of gauge-mediated SUSY breaking

Despite their appealing features, models with gauge-mediated supersymmetry breaking (GMSB) typically present a high degree of fine-tuning, due to the initial absence of the top trilinear scalar couplings, $A_t=0$. In this paper, we carefully evaluate such a tuning, showing that is worse than per mil in the minimal model. Then, we examine some existing proposals to generate $A_t\neq 0$ term in this context. We find that, although the stops can be made lighter, usually the tuning does not improve (it may be even worse), with some exceptions, which involve the generation of $A_t$ at one loop or tree level. We examine both possibilities and propose a conceptually simplified version of the latter; which is arguably the optimum GMSB setup (with minimal matter content), concerning the fine-tuning issue. The resulting fine-tuning is better than one per mil, still severe but similar to other minimal supersymmetric standard model constructions. We also explore the so-called "little $A_t^2/m^2$ problem", i.e. the fact that a large $A_t$-term is normally accompanied by a similar or larger sfermion mass, which typically implies an increase in the fine-tuning. Finally, we find the version of GMSB for which this ratio is optimized, which, nevertheless, does not minimize the fine-tuning.Comment: 16 pages, 11 figures, 1 appendix. Discussion extended, matches EPJC published versio

Squeezed K^+ K^- correlations in high energy heavy ion collisions

The hot and dense medium formed in high energy heavy ion collisions may modify some hadronic properties. In particular, if hadron masses are shifted in-medium, it was demonstrated that this could lead to back-to-back squeezed correlations (BBC) of particle-antiparticle pairs. Although well-established theoretically, the squeezed correlations have not yet been discovered experimentally. A method has been suggested for the empirical search of this effect, which was previously illustrated for phi-phi pairs. We apply here the formalism and the suggested method to the case of K^+ K^- pairs, since they may be easier to identify experimentally. The time distribution of the emission process plays a crucial role in the survival of the BBC's. We analyze the cases where the emission is supposed to occur suddenly or via a Lorentzian distribution, and compare with the case of a Levy distribution in time. Effects of squeezing on the correlation function of identical particles are also analyzed.Comment: 9 pages and 6 figures (figures 2 to 6 contain 4 plots each). Paragraph added to text, figures 2 to 6 revised for improving visualizatio

Results on life cycle assessments to determine impacts of agronomic management choices in the Cauca and Honduras CSV

The intense management of the crops, that characterizes current agricultural cropping systems, has resulted in increased concentrations of greenhouse gases (GHGs) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). In this study, we used the field-scale agricultural assessment model - Cool Farm Tool (CFT), to model GHG emissions and uptake estimates (Hillier et al., 2011). This tool combines different algorithms that integrate climate, soil and crop data and presents outputs on carbon footprints in a format that is accessible to non-experts. Furthermore, the CFT provides the possibility to compare GHG emissions and uptake estimates from different production sites and systems. Finally, the tool CFT enables crop producers and stakeholders to take a more informed and holistic approach to environmental sustainability in the agricultural sector