556 research outputs found
Bounds for partial derivatives: necessity of UMD and sharp constants
We prove the necessity of the UMD condition, with a quantitative estimate of
the UMD constant, for any inequality in a family of bounds between
different partial derivatives of . In particular, we show that the estimate
characterizes the UMD property,
and the best constant is equal to one half of the UMD constant. This
precise value of seems to be new even for scalar-valued functions.Comment: v2: corrected typo in the reference
Conical square function estimates in UMD Banach spaces and applications to H-infinity functional calculi
We study conical square function estimates for Banach-valued functions, and
introduce a vector-valued analogue of the Coifman-Meyer-Stein tent spaces.
Following recent work of Auscher-McIntosh-Russ, the tent spaces in turn are
used to construct a scale of vector-valued Hardy spaces associated with a given
bisectorial operator (A) with certain off-diagonal bounds, such that (A) always
has a bounded (H^{\infty})-functional calculus on these spaces. This provides a
new way of proving functional calculus of (A) on the Bochner spaces
(L^p(\R^n;X)) by checking appropriate conical square function estimates, and
also a conical analogue of Bourgain's extension of the Littlewood-Paley theory
to the UMD-valued context. Even when (X=\C), our approach gives refined
(p)-dependent versions of known results.Comment: 28 pages; submitted for publicatio
Kivennäismaalisäyksen vaikutus turpeen ravinnemääriin ja puiden ravinnetalouteen metsäojitetuilla soilla
The effect of granulated wood-ash fertilization on soil properties and greenhouse gas (GHG) emissions in boreal peatland forests
Borrelios - fakta och fiktion?
Lyme-borrelios är ett aktuellt ämne som väcker mycket debatt bland såväl hälsovårdspersonal
som lekmän. I antalet sjukdomsfall ses en jämnt stigande trend. Fästingar påträffas numera i
hela Finland ända upp till södra Lappland. Risken för borrelios efter ett fästingbett är i genomsnitt 2 procent och därför är ett bett inte en indikation för antibiotikabehandling. Behandlingen
av den typiska hudförändringen, erythema migrans, som uppstår på huden omkring bettet,
består däremot av en antibiotikakur. Inga laboratorieprov behövs i detta skede. </p
Maximal regularity for non-autonomous equations with measurable dependence on time
In this paper we study maximal -regularity for evolution equations with
time-dependent operators . We merely assume a measurable dependence on time.
In the first part of the paper we present a new sufficient condition for the
-boundedness of a class of vector-valued singular integrals which does not
rely on H\"ormander conditions in the time variable. This is then used to
develop an abstract operator-theoretic approach to maximal regularity.
The results are applied to the case of -th order elliptic operators
with time and space-dependent coefficients. Here the highest order coefficients
are assumed to be measurable in time and continuous in the space variables.
This results in an -theory for such equations for .
In the final section we extend a well-posedness result for quasilinear
equations to the time-dependent setting. Here we give an example of a nonlinear
parabolic PDE to which the result can be applied.Comment: Application to a quasilinear equation added. Accepted for publication
in Potential Analysi
The -boundedness of a family of integral operators on UMD Banach function spaces
We prove the -boundedness of a family of integral operators with an
operator-valued kernel on UMD Banach function spaces. This generalizes and
simplifies earlier work by Gallarati, Veraar and the author, where the
-boundedness of this family of integral operators was shown on Lebesgue
spaces. The proof is based on a characterization of -boundedness as
weighted boundedness by Rubio de Francia.Comment: 13 pages. Generalization of arXiv:1410.665
Nitrous oxide production in boreal soils with variable organic matter content at low temperature - snow manipulation experiment.
Atmospheric impact of abandoned boreal organic agricultural soils depends on hydrological conditions
Peer reviewe
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