Gapped boundaries and string-like excitations in (3+1)d gauge models of topological phases

We study lattice Hamiltonian realisations of (3+1)d Dijkgraaf-Witten theory with gapped boundaries. In addition to the bulk loop-like excitations, the Hamiltonian yields bulk dyonic string-like excitations that terminate at gapped boundaries. Using a tube algebra approach, we classify such excitations and derive the corresponding representation theory. Via a dimensional reduction argument, we relate this tube algebra to that describing (2+1)d boundary point-like excitations at interfaces between two gapped boundaries. Such point-like excitations are well known to be encoded into a bicategory of module categories over the input fusion category. Exploiting this correspondence, we define a bicategory that encodes the string-like excitations ending at gapped boundaries, showing that it is a sub-bicategory of the centre of the input bicategory of group-graded 2-vector spaces. In the process, we explain how gapped boundaries in (3+1)d can be labelled by so-called pseudo-algebra objects over this input bicategory

Reconstrucción de los puentes de Chalonnes

Los puentes de la carretera general núm. 161 bis, tronco de la circulación entre norte y sur del Departamento de Main et Loire (Francia), salvan el rio Loire a unos 20 km al oeste de Angers formando tres estructuras diferentes, una para cada brazo del río, que, desde 1841 a 1940, han estado en servicio, si bien con una carga máxima para vehículos de 8,4 toneladas

Innovating standards through informal consortia: The case of wireless telecommunications

International audienceWe empirically examine the effects of industry consortia on the coordination of innovation strategies of the members. Our analyses utilize membership data from 32 consortia in wireless telecommunication technology subfields from 2000 to 2005 and prior art citations in standard-essential patents. We find that connections among firms in informal and technically-oriented consortia significantly increase the likelihood that firms cite each other's patents in subsequent patents essential for the UMTS wireless telecommunication standard. Inventions that are likely to become part of the UMTS system tend to build on inventions by firm peers who were members of the same consortia, controlling for patent or firm fixed effects, technology class, and other characteristics. Consortia may enhance productivity of invention and increase the incentives to invest in R&D by internalizing potential externalities. They may also enhance efficiency of standardization by facilitating the interaction of committee and market processes. Consortia thus structure and constrain the process of innovating standardized technologies. This is problematic if consortia are not truly accessible for all the relevant parties. Policymakers thus need to balance these effects. For managers, the results show that participation in a variety of technical consortia enables influencing peers' innovation strategies related to compatibility standards

L’archéologie forestière dans le Châtillonnais de la prospection pédestre aux relevés LiDAR

National audienc

Dealing with paralogy in RADseq data: in silico detection and single nucleotide polymorphism validation in Robinia pseudoacacia L.

peer reviewedThe RADseq technology allows researchers to efficiently develop thousands of polymorphic loci across multiple individuals with little or no prior information on the genome. However, many questions remain about the biases inherent to this technology. Notably, sequence misalignments arising from paralogy may affect the development of single nucleotide polymorphism (SNP) markers and the estimation of genetic diversity. We evaluated the impact of putative paralog loci on genetic diversity estimation during the development of SNPs from a RADseq dataset for the nonmodel tree species Robinia pseudoacacia L. We sequenced nine genotypes and analyzed the frequency of putative paralogous RAD loci as a function of both the depth of coverage and the mismatch threshold allowed between loci. Putative paralogy was detected in a very variable number of loci, from 1% to more than 20%, with the depth of coverage having a major influence on the result. Putative paralogy artificially increased the observed degree of polymorphism and resulting estimates of diversity. The choice of the depth of coverage also affected diversity estimation and SNP validation: A low threshold decreased the chances of detecting minor alleles while a high threshold increased allelic dropout. SNP validation was better for the low threshold (4×) than for the high threshold (18×) we tested. Using the strategy developed here, we were able to validate more than 80% of the SNPs tested by means of individual genotyping, resulting in a readily usable set of 330 SNPs, suitable for use in population genetics applications

Isolation of stable non cyclic 1,2-disulfoxides: revisiting the thermolysis of S-aryl sulfinimines

The thermolysis of S-aryl sulfinimines is shown to generate 1,2-disulfoxides and disulfides via initial Cope elimination, dimerisation of the produced sulfenic acid to a thiosulfinate, and subsequent disproportionation of the thiosulfinate

Allylic Oxidation of Alkenes Catalyzed by a Copper−Aluminum Mixed Oxide

A strategy for the allylic oxidation of cyclic alkenes with a copper−aluminum mixed oxide as catalyst is presented. The reaction involves the treatment of an alkene with a carboxylic acid employing tert-butyl hydroperoxide as the oxidant. In all cases, the corresponding allylic esters are obtained. When L-proline is employed, the allylic alcohol or ketone is obtained. The oxidation of cyclohexene and valencene has been optimized by design of experiments (DoE) statistical methodology

Acyloxylation of Cyclic Enones: Synthesis of Densely Oxygenated Guaianolides

The α′-acyloxylation of cyclic enones with linear carboxylic acids is described. The reaction is promoted by KMnO4 in the presence of a carboxylic acid and its corresponding carboxylic anhydride. The optimization of the reaction has been carried out using the statistical methodology known as design of experiments. The optimized reaction conditions have been evaluated in terms of substrate scope and compatibility with different functional groups. The methodology has been applied to the synthesis of densely oxygenated guaianes and guaianolides