Results 1 to 10 of about 296 (61)
Automorphism group schemes of bielliptic and quasi-bielliptic surfaces [PDF]
Épijournal de Géométrie Algébrique, 2022 Bielliptic and quasi-bielliptic surfaces form one of the four classes of minimal smooth projective surfaces of Kodaira dimension $0$. In this article, we determine the automorphism schemes of these surfaces over algebraically closed fields of arbitrary ...
Gebhard Martin
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Finite torsors over strongly $F$-regular singularities [PDF]
Épijournal de Géométrie Algébrique, 2022 We investigate finite torsors over big opens of spectra of strongly $F$-regular germs that do not extend to torsors over the whole spectrum. Let $(R,\mathfrak{m},k)$ be a strongly $F$-regular $k$-germ where $k$ is an algebraically closed field of ...
Javier Carvajal-Rojas
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Dieudonné theory via cohomology of classifying stacks
Forum of Mathematics, Sigma, 2021 We prove that if G is a finite flat group scheme of p-power rank over a perfect field of characteristic p, then the second crystalline cohomology of its classifying stack $H^2_{\text {crys}}(BG)$ recovers the Dieudonné module of G.
Shubhodip Mondal
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Grothendieck–Serre in the quasi-split unramified case
Forum of Mathematics, Pi, 2022 The Grothendieck–Serre conjecture predicts that every generically trivial torsor under a reductive group scheme G over a regular local ring R is trivial. We settle it in the case when G is quasi-split and R is unramified.
Kęstutis Česnavičius
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The maximal unipotent finite quotient, unusual torsion in Fano threefolds, and exceptional Enriques surfaces [PDF]
Épijournal de Géométrie Algébrique, 2020 We introduce and study the maximal unipotent finite quotient for algebraic group schemes in positive characteristics. Applied to Picard schemes, this quotient encodes unusual torsion.
Andrea Fanelli, Stefan Schröer
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Sur l'existence du sch\'ema en groupes fondametal [PDF]
Épijournal de Géométrie Algébrique, 2020 Let $S$ be a Dedekind scheme, $X$ a connected $S$-scheme locally of finite type and $x\in X(S)$ a section. The aim of the present paper is to establish the existence of the fundamental group scheme of $X$, when $X$ has reduced fibers or when $X$ is ...
Marco Antei +2 more
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Grassmanniennes affines tordues sur les entiers
Forum of Mathematics, Sigma, 2023 We generalize the works of Pappas–Rapoport–Zhu on twisted affine Grassmannians to the wildly ramified case under mild assumptions. This rests on a construction of certain smooth affine $\mathbb {Z}[t]$ -groups with connected fibers of parahoric ...
João Lourenço
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Free Proalgebraic Groups [PDF]
Épijournal de Géométrie Algébrique, 2020 Replacing finite groups by linear algebraic groups, we study an algebraic-geometric counterpart of the theory of free profinite groups. In particular, we introduce free proalgebraic groups and characterize them in terms of embedding problems.
Michael Wibmer
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Veterinary Dermatology, Volume 33, Issue 4, Page 316-e73, August 2022., 2022 Abstract Background Pseudomonas aeruginosa is the most commonly isolated bacterium from skin lesions of dogs with post‐grooming furunculosis (PGF). It is frequently found in human hair and skin care products, and may pose a health risk to consumers. Information regarding the prevalence of P. aeruginosa contamination of dog grooming products is lacking.
Elad Perry +5 more
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Reproducibility of serum testing for environmental allergen‐specific IgE in dogs in Europe
Veterinary Dermatology, Volume 32, Issue 3, Page 251-e67, June 2021., 2021 Background – Serum testing for allergen‐specific immunoglobulin (Ig)E is commonly employed to identify allergens used for allergen‐specific immunotherapy in dogs, yet the reliability of results has been a matter of debate. Objective – The aim of this study was to evaluate the reproducibility of serum tests for environmental allergen‐specific IgE in ...
Katja N. Baumann +4 more
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