MIT Open Access Articles
http://hdl.handle.net/1721.1/49433
2016-09-29T15:21:23ZChow groups of intersections of quadrics via homological projective duality and (Jacobians of) non-commutative motives
http://hdl.handle.net/1721.1/104384
Chow groups of intersections of quadrics via homological projective duality and (Jacobians of) non-commutative motives
Bernardara, M.; Trigo Neri Tabuada, Goncalo Jorge
Conjectures of Beilinson-Bloch type predict that the low-degree rational Chow groups of intersections of quadrics are one-dimensional. This conjecture was proved by Otwinowska in [20]. By making use of homological projective duality and the recent theory of (Jacobians of) non-commutative motives, we give an alternative proof of this conjecture in the case of a complete intersection of either two quadrics or three odd-dimensional quadrics. Moreover, we prove that in these cases the unique non-trivial algebraic Jacobian is the middle one. As an application, we make use of Vial's work [26], [27] to describe the rational Chow motives of these complete intersections and show that smooth fibrations into such complete intersections over bases S of small dimension satisfy Murre's conjecture (when dim(S) [less than or equal to] 1), Grothendieck's standard conjecture of Lefschetz type (when dim(S) [less than or equal to] 2), and Hodge's conjecture (when dim(S) [less than or equal to] 3).
2016-07-01T00:00:00ZMinimizers of Anisotropic Surface Tensions Under Gravity: Higher Dimensions via Symmetrization
http://hdl.handle.net/1721.1/104380
Minimizers of Anisotropic Surface Tensions Under Gravity: Higher Dimensions via Symmetrization
Baer, Eric
We consider a variational model describing the shape of liquid drops and crystals under the influence of gravity, resting on a horizontal surface. Making use of anisotropic symmetrization techniques, we establish the existence, convexity and symmetry of minimizers for a class of surface tensions admissible to the symmetrization procedure. In the case of smooth surface tensions, we obtain the uniqueness of minimizers via an ODE characterization.
2014-08-01T00:00:00ZOccurrence and genetic diversity of human cosavirus in influent and effluent of wastewater treatment plants in Arizona, United States
http://hdl.handle.net/1721.1/104379
Occurrence and genetic diversity of human cosavirus in influent and effluent of wastewater treatment plants in Arizona, United States
Kitajima, Masaaki; Haramoto, Eiji; Rachmadi, Andri T.; Iker, Brandon C.; Pepper, Ian L.; Gerba, Charles P.
Human cosavirus (HCoSV) is a novel member of the family Picornaviridae. We investigated the prevalence and genetic diversity of HCoSV in influent and effluent wastewater in Arizona over a 12-month period, from August 2011 to July 2012. HCoSV sequences were identified in six (25 %) influent samples and one (4 %) effluent sample, with the highest concentration of 3.24 x 10[superscript 5] and 1.54 x 10³ copies/liter in influent and effluent, respectively. The strains were characterized based on their 5’ untranslated region and classified into species A and D, demonstrating that genetically heterogeneous HCoSV were circulating with a clear temporal shift of predominant strains in the study area.
2015-05-01T00:00:00ZComputing Néron–Severi groups and cycle class groups
http://hdl.handle.net/1721.1/104378
Computing Néron–Severi groups and cycle class groups
Testa, Damiano; van Luijk, Ronald; Poonen, Bjorn
Assuming the Tate conjecture and the computability of étale cohomology with finite coefficients, we give an algorithm that computes the Néron–Severi group of any smooth projective geometrically integral variety, and also the rank of the group of numerical equivalence classes of codimension p cycles for any p.
2015-02-01T00:00:00Z