521 research outputs found
Sharp Lorentz estimates for dyadic-like maximal operators and related Bellman functions
We precisely evaluate Bellman type functions for the dyadic maximal opeator
on and of maximal operators on martingales related to local Lorentz type
estimates. Using a type of symmetrization principle, introduced for the dyadic
maximal operator in earlier works of the authors we precisely evaluate the
supremum of the Lorentz quasinorm of the maximal operator on a function
when the integral of is fixed and also the same Lorentz quasinorm of
is fixed. Also we find the corresponding supremum when the integral of
is fixed and several weak type conditions are given.Comment: 11 page
Dyadic weights on and reverse Holder inequalities
We prove that for any weight defined on that satisfies a
reverse Holder inequality with exponent p > 1 and constant upon all
dyadic subcubes of , it's non increasing rearrangement satisfies a
reverse Holder inequality with the same exponent and constant not more than
, upon all subintervals of of the form . This
gives as a consequence, according to the results in [8], an interval , such that for any , we have that is
in .Comment: 10 page
Local lower norm estimates for dyadic maximal operators and related Bellman functions
We provide lower and weak -bounds for the localized dyadic maximal
operator on , when the local and the local norm of the
function are given. We actually do that in the more general context of homo-
geneous tree-like families in probability spaces.Comment: 9 page
Estimates for Bellman functions related to dyadic-like maximal operators on weighted spaces
We provide some new estimates for Bellman type functions for the dyadic
maximal opeator on and of maximal operators on martingales related to
weighted spaces. Using a type of symmetrization principle, introduced for the
dyadic maximal operator in earlier works of the authors we introduce certain
conditions on the weight that imply estimate for the maximal operator on the
corresponding weighted space. Also using a well known estimate for the maximal
operator by a double maximal operators on different m easures related to the
weight we give new estimates for the above Bellman type functions.Comment: 10 pages. arXiv admin note: text overlap with arXiv:1511.0611
On weak type inequalities for dyadic maximal functions
AbstractWe obtain sharp estimates for the localized distribution function of the dyadic maximal function Mϕd, given the local L1 norms of ϕ and of G○ϕ where G is a convex increasing function such that G(x)/x→+∞ as x→+∞. Using this we obtain sharp refined weak type estimates for the dyadic maximal operator
Evolution of perturbations in 3D air quality models
The deterministic approach of sensitivity analysis is applied on the solution vector of an Air Quality Model. In
particular, the photochemical CAMx code is augmented with derivatives utilising the automatic differentiation
software ADIFOR. The enhanced with derivatives version of the model is then adopted in a study of the effect of
perturbations at the boundary conditions on the predicted ozone concentrations. The calculated derivative matrix
provides valuable information e.g., on the ordering of the infl uential factors or the localisation of highly affected
regions. Two fundamentally different domains of the Auto-Oil II programme were used as test cases for the
simulations, namely Athens and Milan. The results suggest that ozone concentration be highly affected by its own
boundary conditions and subsequently, with an order of magnitude less, by the boundary conditions of NOX and VOC
An Integrated Decision-Support Information System on the Impact of Extreme Natural Hazards on Critical Infrastructure
In this paper, we introduce an Integrated Decision-Support Tool (IDST v2.0) which was developed as part of the INFRARISK project (https://www.infrarisk-fp7.eu/). The IDST is an online tool which demonstrates the implementation of a risk-based stress testing methodology for analyzing the potential impact of natural hazards on transport infrastructure networks. The IDST is enabled with a set of software workflow processes that allow the definition of multiple cascading natural hazards, geospatial coverage and impact on important large infrastructure, including those which are critical to transport networks in Europe. Stress tests on these infrastructure are consequently performed together with the automated generation of useful case study reports for practitioners. An exemplar stress test study using the IDST is provided in this paper. In this study, risks and consequences of an earthquake-triggered landslide scenario in Northern Italy is described. Further, it provides a step-by-step account of the developed stress testing overarching methodology which is applied to the impact on a road network of the region of interest
Intracisternal delivery of NFκB-inducible scAAV2/9 reveals locoregional neuroinflammation induced by systemic kainic acid treatment.
We have previously demonstrated disease-dependent gene delivery in the brain using an AAV vector responding to NFκB activation as a probe for inflammatory responses. This vector, injected focally in the parenchyma prior to a systemic kainic acid (KA) injection mediated inducible transgene expression in the hippocampus but not in the cerebellum, regions, respectively, known to be affected or not by the pathology. However, such a focal approach relies on previous knowledge of the model parameters and does not allow to predict the whole brain response to the disease. Global brain gene delivery would allow to predict the regional distribution of the pathology as well as to deliver therapeutic factors in all affected brain regions. We show that self-complementary AAV2/9 (scAAV2/9) delivery in the adult rat cisterna magna allows a widespread but not homogenous transduction of the brain. Indeed, superficial regions, i.e., cortex, hippocampus, and cerebellum were more efficiently transduced than deeper regions, such as striatum, and substantia nigra. These data suggest that viral particles penetration from the cerebrospinal fluid (CSF) into the brain is a limiting factor. Interestingly, AAV2/9-2YF a rationally designed capsid mutant (affecting surface tyrosines) increased gene transfer efficiency approximately fivefold. Neurons, astrocytes, and oligodendrocytes, but not microglia, were transduced in varying proportions depending on the brain region and the type of capsid. Finally, after a single intracisternal injection of scAAV2/9-2YF using the NFκB-inducible promoter, KA treatment induced transgene expression in the hippocampus and cortex but not in the cerebellum, corresponding to the expression of the CD11b marker of microglial activation. These data support the use of disease-inducible vectors administered in the cisterna magna as a tool to characterize the brain pathology in systemic drug-induced or transgenic disease models. However, further improvements are required to enhance viral particles penetration into the brain
- …