Exact sequences, lower central series and representations of surface braid groups

We consider exact sequences and lower central series of surface braid groups and we explain how they can prove to be useful for obtaining representations for surface braid groups. In particular, using a completely algebraic framework, we describe the notion of extension of a representation introduced and studied recently by An and Ko and independently by Blanchet.Comment: 23 pages, 4 figure

Lower central series for surface braid groups

21 pages ; 2 figuresWe determine the lower central series and corresponding residual properties for braid groups and pure braid groups of orientable surfaces

Kosmos, il nuovo progetto culturale dell’Università di Pavia per le collezioni di storia naturale

Kosmos, the new cultural project of the University of Pavia for its Natural History collections Kosmos, the new Natural History Museum, adopted for its new exhibition strategies dedicated to the accessibility of the collections. The gallery was therefore enriched with exhibits and games with the aim of conveying scientific content in an engaging form. For guided tours and workshops Kosmos makes use of the collaboration of ADMaiora, a company that provides educational services. Together with the museum’ staff ADMaiora has developed an educational offer capable of making museum content accessible at all levels, including audiences who present disabilities. To support the visit few didactic kits have been added and a new palaeontology laboratory kit for small groups with cognitive disabilities has been created. Finally, a "social history" document that adopt Augmentative Alternative Communication (AAC) was drawn up to prepare children with specific relational disabilities to the visi

Il Sistema Museale dell’Università di Pavia ai tempi del coronavirus

Kosmos, the new cultural project of the University of Pavia for its Natural History collections Kosmos, the new Natural History Museum, adopted for its new exhibition strategies dedicated to the accessibility of the collections. The gallery was therefore enriched with exhibits and games with the aim of conveying scientific content in an engaging form. For guided tours and workshops Kosmos makes use of the collaboration of ADMaiora, a company that provides educational services. Together with the museum’ staff ADMaiora has developed an educational offer capable of making museum content accessible at all levels, including audiences who present disabilities. To support the visit few didactic kits have been added and a new palaeontology laboratory kit for small groups with cognitive disabilities has been created. Finally, a "social history" document that adopt Augmentative Alternative Communication (AAC) was drawn up to prepare children with specific relational disabilities to the visit

La Collezione Tommasi dei fossili della “Lumachella di Ghegna” (Roncobello, Val Brembana, BG) conservata nel Museo di Storia Naturale dell’Università di Pavia, ed altre collezioni triassiche

Annibale Tommasi si occupò principalmente delle faune a invertebrati marini del Triassico alpino. Una di queste, di notevole importanza paleontologica e stratigrafica, è la fauna della “Lumachella di Ghegna” rinvenuta nella Pineta di Ghegna presso Roncobello, in Val Brembana (Bergamo). La “Lumachella di Ghegna” è una facies particolare della base del Calcare di Esino (Triassico Medio). Tale facies viene attribuita, almeno in parte, al limite Anisico/Ladinico grazie alla presenza di alcuni ammonoidi di sicuro valore stratigrafico. Su questa fauna Tommasi pubblicò un importante lavoro, diviso in due parti: la prima (1911b) dedicata ai brachiopodi, bivalvi, alghe e coralli; la seconda (1913) dedicata ai gasteropodi, cefalopodi e scafopodi. Viene inoltre resa nota la presenza di altre collezioni triassiche pubblicate da Tommasi formate da materiali provenienti dalle seguenti località lombarde: Rasa di Varese (VA), Varenna (LC), Valle del Dezzo (Orobie), Valsecca presso Roncobello (BG), da siti tipici per la formazione della Dolomia Principale compresi nelle province di Bergamo e Brescia, e da altre località italiane: Monte Clapsavon (Alpi Carniche), Marmolada (Dolomiti)

Allestimento di una banca biologica del DNA di primati: un nuovo approccio alle collezioni storiche. Museologia Scientifica

Il Museo di Storia Naturale dell’Università di Pavia, fondato nel 1771 da Lazzaro Spallanzani, rivestì un ruolo molto importante in seno alle strutture scientifiche dell’Ateneo. Nel dopoguerra perse via via il suo ruolo fino a essere abbandonato. Dal 1989 l’Università ha iniziato il recupero delle collezioni con il fine di riavvicinare il Museo alle istituzioni scientifiche. Nel 2014 in collaborazione con il Dipartimento di Scienze della Terra e dell’Ambiente è stato avviato un lavoro per l’allestimento di una banca biologica del DNA della collezione di primati che ha comportato la messa a punto di procedure di estrazione e di analisi del DNA antico

Abelian and metabelian quotients of surface braid groups

This paper supersedes arXiv:1106.4982. The results of previous paper have been revisited and improved and new results have been added.In this paper we study abelian and metabelian quotients of braid groups on oriented surfaces with boundary components. We provide group presentations and we prove rigidity results for these quotients arising from exact sequences related to (generalised) Fadell-Neuwirth fibrations

Unrestricted virtual braids and crystallographic braid groups

We show that the crystallographic braid group $B_n/[P_n,P_n]$ embeds naturally in the group of unrestricted virtual braids $UVB_n$, we give new proofs of known results about the torsion elements of $B_n/[P_n,P_n]$, and we characterise the torsion elements of $UVB_n$

Abelian and metabelian quotient groups of surface braid groups

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