A complete characterisation of All-versus-Nothing arguments for stabiliser states

An important class of contextuality arguments in quantum foundations are the All-versus-Nothing (AvN) proofs, generalising a construction originally due to Mermin. We present a general formulation of All-versus-Nothing arguments, and a complete characterisation of all such arguments which arise from stabiliser states. We show that every AvN argument for an n-qubit stabiliser state can be reduced to an AvN proof for a three-qubit state which is local Clifford-equivalent to the tripartite GHZ state. This is achieved through a combinatorial characterisation of AvN arguments, the AvN triple Theorem, whose proof makes use of the theory of graph states. This result enables the development of a computational method to generate all the AvN arguments in $\mathbb{Z}_2$ on n-qubit stabiliser states. We also present new insights into the stabiliser formalism and its connections with logic.Comment: 18 pages, 6 figure

Evolution of CONSTANS Transcriptional Regulation and Protein Function in the Brassicaceae Family

Plants respond to seasonal changes in day length to control developmental transitions such as flowering and bud dormancy. In the model plant Arabidopsis thaliana (A. thaliana), CONSTANS (CO) activates the expression of FLOWERING LOCUS T (FT) specifically under long days, and FT protein then moves from the leaf to the shoot apical meristem where it promotes the transition to flowering. CO transcription is precisely regulated so that its mRNA is repressed in the morning and rises in the evening of a long day allowing activation of FT. Therefore, the diurnal pattern of CO transcription is an essential component of the regulation of flowering time in A. thaliana. The two closest homologs of CO in A. thaliana, CONSTANS-like 1 (COL1) and COL2 have no function in photoperiodic flowering response and show different mRNA patterns. All three genes evolved from a common ancestor after the latest whole genome duplication (At-α) in the lineage leading to A. thaliana that is believed to have occurred ~43 mya. The transcriptional patterns of CO and COL2 are conserved in the basal Brassicaceae species Aethionema arabicum. Also the CO homolog of this species but not its COL2 homolog can complement the co mutation in A. thaliana. As the Aethionema lineage represents the earliest split in the evolution of the Brassicaceae these findings indicate that CO function was already present at an early stage of Brassicaceae evolution and its activity is likely conserved throughout the family. The promoter of CO contains conserved sequence blocks which are shared in orthologs examined in ten Brassicaceaen species. DOF binding sites, E-Boxes and TCP binding sites are the most abundant cis-elements identified in ten CO promoters. Furthermore, DOF and TCP binding sites are strongly enriched in the promoters of CO genes compared to COL gene promoters. DOF binding sites are reported to enable binding of repressive CDF Transcription factors and were among the most highly conserved motifs in the promoters of CO orthologs. E-Boxes are putative binding sites for FLOWERING bHLH (FBH) TFs that function as transcriptional activators of CO. No role has so far been assigned for TCP transcription factors in regulation of CO transcription. Promoter reporter studies in A. thaliana revealed that the CO promoter contains functional regulatory sequences up to 2.6kb from the TS and that a short conserved regulatory motif that comprises DOF binding sites and is present both distally and proximally is sufficient to recreate mRNA patterns highly similar to endogenous CO. A model for the evolution of CO promoter is proposed in which downstream conserved DOF binding sites appeared distally upstream to regulate CO after the gene duplication leading to its diversification from COL1. Tarenaya hassleriana, a member of the Cleomaceae family which is sister to the Brassicaceae, has only one ortholog of CO (ThCOL) which shares one last common ancestral gene with CO, COL1 and COL2. ThCOL protein sequence is most similar to COL2 homologs from the Brassicaceae family. Additionally mRNA expression pattern and lower ability to promote early flowering in A. thaliana are common characteristics of this gene with COL1 and COL2 but not with CO. Hence, the transcriptional regulation of CO as well as an increase in capacity to promote flowering when compared to its close homologs COL1 and COL2 evolved in the Brassicaceae family and represents a novelty that arose in this family. My evolutionary studies indicate that CO evolved by gene duplication at the root of the Brassicaceae family. This gene then evolved a function in photoperiodic flowering through changes to its transcriptional regulation and protein function. Such a history contradicts the current view that CO has an ancient history predating the divergence of monocotyledonous and dicotyledonous angiosperms, but rather suggests that the role of CO homologous genes in conferring photoperiodic flowering might have evolved independently in different families of higher plants

A non-interleaving process calculus for multi-party synchronisation

We introduce the wire calculus. Its dynamic features are inspired by Milner's CCS: a unary prefix operation, binary choice and a standard recursion construct. Instead of an interleaving parallel composition operator there are operators for synchronisation along a common boundary and non-communicating parallel composition. The (operational) semantics is a labelled transition system obtained with SOS rules. Bisimilarity is a congruence with respect to the operators of the language. Quotienting terms by bisimilarity results in a compact closed category

Characterization of the Ca2+-gated and voltage-dependent k+-channel slo-1 of nematodes and its interaction with emodepside

The cyclooctadepsipeptide emodepside and its parent compound PF1022A are broad-spectrum nematicidal drugs which are able to eliminate nematodes resistant to other anthelmintics. The mode of action of cyclooctadepsipeptides is only partially understood, but involves the latrophilin Lat-1 receptor and the voltage- and calcium-activated potassium channel Slo-1. Genetic evidence suggests that emodepside exerts its anthelmintic activity predominantly through Slo-1. Indeed, slo-1 deficient Caenorhabditis elegans strains are completely emodepside resistant. However, direct effects of emodepside on Slo-1 have not been reported and these channels have only been characterized for C. elegans and related Strongylida. Molecular and bioinformatic analyses identified full-length Slo-1 cDNAs of Ascaris suum, Parascaris equorum, Toxocara canis, Dirofilaria immitis, Brugia malayi, Onchocerca gutturosa and Strongyloides ratti. Two paralogs were identified in the trichocephalids Trichuris muris, Trichuris suis and Trichinella spiralis. Several splice variants encoding truncated channels were identified in Trichuris spp. Slo-1 channels of trichocephalids form a monophyletic group, showing that duplication occurred after the divergence of Enoplea and Chromadorea. To explore the function of a representative protein, C. elegans Slo-1a was expressed in Xenopus laevis oocytes and studied in electrophysiological (voltage-clamp) experiments. Incubation of oocytes with 1-10 µM emodepside caused significantly increased currents over a wide range of step potentials in the absence of experimentally increased intracellular Ca2+, suggesting that emodepside directly opens C. elegans Slo-1a. Emodepside wash-out did not reverse the effect and the Slo-1 inhibitor verruculogen was only effective when applied before, but not after, emodepside. The identification of several splice variants and paralogs in some parasitic nematodes suggests that there are substantial differences in channel properties among species. Most importantly, this study showed for the first time that emodepside directly opens a Slo-1 channel, significantly improving the understanding of the mode of action of this drug class

Plants Developed by New Genetic Modification Techniques—Comparison of Existing Regulatory Frameworks in the EU and Non-EU Countries

The development of new genetic modification techniques (nGMs), also referred to as “new (breeding) techniques” in other sources, has raised worldwide discussions regarding their regulation. Different existing regulatory frameworks for genetically modified organisms (GMO) cover nGMs to varying degrees. Coverage of nGMs depends mostly on the regulatory trigger. In general two different trigger systems can be distinguished, taking into account either the process applied during development or the characteristics of the resulting product. A key question is whether regulatory frameworks either based on process- or product-oriented triggers are more advantageous for the regulation of nGM applications. We analyzed regulatory frameworks for GMO from different countries covering both trigger systems with a focus on their applicability to plants developed by various nGMs. The study is based on a literature analysis and qualitative interviews with regulatory experts and risk assessors of GMO in the respective countries. The applied principles of risk assessment are very similar in all investigated countries independent of the applied trigger for regulation. Even though the regulatory trigger is either process- or product-oriented, both triggers systems show features of the respective other in practice. In addition our analysis shows that both trigger systems have a number of generic advantages and disadvantages, but neither system can be regarded as superior at a general level. More decisive for the regulation of organisms or products, especially nGM applications, are the variable criteria and exceptions used to implement the triggers in the different regulatory frameworks. There are discussions and consultations in some countries about whether changes in legislation are necessary to establish a desired level of regulation of nGMs. We identified five strategies for countries that desire to regulate nGM applications for biosafety–ranging from applying existing biosafety frameworks without further amendments to establishing new stand-alone legislation. Due to varying degrees of nGM regulation, international harmonization will supposedly not be achieved in the near future. In the context of international trade, transparency of the regulatory status of individual nGM products is a crucial issue. We therefore propose to introduce an international public registry listing all biotechnology products commercially used in agriculture

Effects of reflux laryngitis on non-nutritive swallowing in newborn lambs

Reflux laryngitis in infants may be involved not only in laryngeal disorders, but also in disorders of cardiorespiratory control through its impact on laryngeal function. Our objective was to study the effect of reflux laryngitis on non-nutritive swallowing (NNS) and NNS-breathing coordination. Two groups of six newborn lambs, randomized into laryngitis and control groups, were surgically instrumented for recording states of alertness, swallowing and cardiorespiratory variables without sedation. A mild to moderate reflux laryngitis was induced in lambs from the experimental group. A significant decrease in the number of NNS bursts and apneas was observed in the laryngitis group in active sleep (p=0.03). In addition, lower heart and respiratory rates, as well as prolonged apnea duration (p<0.0001) were observed. No physiologically significant alterations in NNS-breathing coordination were observed in the laryngitis group. We conclude that a mild to moderate reflux laryngitis alters NNS burst frequency and autonomous control of cardiac activity and respiration in lambs