ana vargas | Universidad Autonoma de Yucatan (original) (raw)
Papers by ana vargas
American Journal of Mathematics, 2008
Environmental Health Perspectives, 2005
Health burdens associated with poor housing and indoor pest infestations are likely to affect you... more Health burdens associated with poor housing and indoor pest infestations are likely to affect young children in particular, who spend most of their time indoors at home. We completed environmental assessments in 644 homes of pregnant Latina women and their children living in the Salinas Valley, California. High residential densities were common, with 39% of homes housing > 1.5 persons per room. Housing disrepair was also common: 58% of homes had peeling paint, 43% had mold, 25% had water damage, and 11% had rotting wood. Evidence of cockroaches and rodents was present in 60% and 32% of homes, respectively. Compared with representative national survey data from the U.S. Department of Housing and Urban Development, homes in our sample were more likely to have rodents, peeling paint, leaks under sinks, and much higher residential densities. The odds of rodent infestations in homes increased in the presence of peeling paint [odds ratio (OR) 2.1; 95% confidence interval (CI), 1.5-3.1], water damage (OR 1.9; 95% CI, 1.2-2.7), and mold (OR 1.5; 95% CI, 1.0-2.1). The odds of cockroach infestation increased in the presence of peeling paint (OR 3.8; 95% CI, 2.7-5.6), water damage (OR 1.9; 95% CI, 1.2-2.9), or high residential density (OR 2.1; 95% CI, 1.2-3.8). Homes that were less clean than average were more prone to both types of infestations. Pesticides were stored or used in 51% of households, partly to control roach and rodent infestations. These data indicate that adverse housing conditions are common in this community and increase the likelihood of pest infestations and home pesticide use. Interventions to improve housing and promote children's health and safety in this population are needed.
In this work we improve our result in . We prove a strong-type almost-orthogonality principle for... more In this work we improve our result in . We prove a strong-type almost-orthogonality principle for maximal functions along several directions. We use geometric methods and a covering lemma.
In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, o... more In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, on the weak-type norm of a maximal operator associated with an arbitrary collection of directions in the plane. The proof relies upon a geometric argument and on induction with respect to the number of directions. Applications are given to estimate the behavior of several types of maximal operators.
Mathematische Annalen, 2006
We discuss the manner in which one might expect directional maximal functions to control the Four... more We discuss the manner in which one might expect directional maximal functions to control the Fourier extension operator via L 2 weighted inequalities. We prove a general inequality of this type for the extension operator restricted to circles in the plane.
In this work we improve our result in . We prove a strong-type almost-orthogonality principle for... more In this work we improve our result in . We prove a strong-type almost-orthogonality principle for maximal functions along several directions. We use geometric methods and a covering lemma.
Journal D Analyse Mathematique, 2007
In this work, we establish certain equivalences between the localisation properties with respect ... more In this work, we establish certain equivalences between the localisation properties with respect to spherical Fourier means of the support of a given Borel measure and the L 2-rate of decay of the Fourier extension operator associated to it. This, in turn, is intimately connected with the property that the X-ray transform of the measure be uniformly bounded. Geometric properties of sets supporting such a measure are studied.
In this work we improve our result in . We prove a strong-type almost-orthogonality principle for... more In this work we improve our result in . We prove a strong-type almost-orthogonality principle for maximal functions along several directions. We use geometric methods and a covering lemma.
In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, o... more In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, on the weak-type norm of a maximal operator associated with an arbitrary collection of directions in the plane. The proof relies upon a geometric argument and on induction with respect to the number of directions. Applications are given to estimate the behavior of several types of maximal operators.
In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, o... more In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, on the weak-type norm of a maximal operator associated with an arbitrary collection of directions in the plane. The proof relies upon a geometric argument and on induction with respect to the number of directions. Applications are given to estimate the behavior of several types of maximal operators.
Mathematische Annalen, 2006
We discuss the manner in which one might expect directional maximal functions to control the Four... more We discuss the manner in which one might expect directional maximal functions to control the Fourier extension operator via L 2 weighted inequalities. We prove a general inequality of this type for the extension operator restricted to circles in the plane.
Mathematische Annalen, 2006
We discuss the manner in which one might expect directional maximal functions to control the Four... more We discuss the manner in which one might expect directional maximal functions to control the Fourier extension operator via L 2 weighted inequalities. We prove a general inequality of this type for the extension operator restricted to circles in the plane.
Journal D Analyse Mathematique, 2007
In this work, we establish certain equivalences between the localisation properties with respect ... more In this work, we establish certain equivalences between the localisation properties with respect to spherical Fourier means of the support of a given Borel measure and the L 2-rate of decay of the Fourier extension operator associated to it. This, in turn, is intimately connected with the property that the X-ray transform of the measure be uniformly bounded. Geometric properties of sets supporting such a measure are studied.
Journal D Analyse Mathematique, 2007
In this work, we establish certain equivalences between the localisation properties with respect ... more In this work, we establish certain equivalences between the localisation properties with respect to spherical Fourier means of the support of a given Borel measure and the L 2-rate of decay of the Fourier extension operator associated to it. This, in turn, is intimately connected with the property that the X-ray transform of the measure be uniformly bounded. Geometric properties of sets supporting such a measure are studied.
Deterioro Ambiental. Concepto.-Escrito por Carlos Mota el 06/02/2007
American Journal of Mathematics, 2008
Environmental Health Perspectives, 2005
Health burdens associated with poor housing and indoor pest infestations are likely to affect you... more Health burdens associated with poor housing and indoor pest infestations are likely to affect young children in particular, who spend most of their time indoors at home. We completed environmental assessments in 644 homes of pregnant Latina women and their children living in the Salinas Valley, California. High residential densities were common, with 39% of homes housing > 1.5 persons per room. Housing disrepair was also common: 58% of homes had peeling paint, 43% had mold, 25% had water damage, and 11% had rotting wood. Evidence of cockroaches and rodents was present in 60% and 32% of homes, respectively. Compared with representative national survey data from the U.S. Department of Housing and Urban Development, homes in our sample were more likely to have rodents, peeling paint, leaks under sinks, and much higher residential densities. The odds of rodent infestations in homes increased in the presence of peeling paint [odds ratio (OR) 2.1; 95% confidence interval (CI), 1.5-3.1], water damage (OR 1.9; 95% CI, 1.2-2.7), and mold (OR 1.5; 95% CI, 1.0-2.1). The odds of cockroach infestation increased in the presence of peeling paint (OR 3.8; 95% CI, 2.7-5.6), water damage (OR 1.9; 95% CI, 1.2-2.9), or high residential density (OR 2.1; 95% CI, 1.2-3.8). Homes that were less clean than average were more prone to both types of infestations. Pesticides were stored or used in 51% of households, partly to control roach and rodent infestations. These data indicate that adverse housing conditions are common in this community and increase the likelihood of pest infestations and home pesticide use. Interventions to improve housing and promote children's health and safety in this population are needed.
In this work we improve our result in . We prove a strong-type almost-orthogonality principle for... more In this work we improve our result in . We prove a strong-type almost-orthogonality principle for maximal functions along several directions. We use geometric methods and a covering lemma.
In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, o... more In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, on the weak-type norm of a maximal operator associated with an arbitrary collection of directions in the plane. The proof relies upon a geometric argument and on induction with respect to the number of directions. Applications are given to estimate the behavior of several types of maximal operators.
Mathematische Annalen, 2006
We discuss the manner in which one might expect directional maximal functions to control the Four... more We discuss the manner in which one might expect directional maximal functions to control the Fourier extension operator via L 2 weighted inequalities. We prove a general inequality of this type for the extension operator restricted to circles in the plane.
In this work we improve our result in . We prove a strong-type almost-orthogonality principle for... more In this work we improve our result in . We prove a strong-type almost-orthogonality principle for maximal functions along several directions. We use geometric methods and a covering lemma.
Journal D Analyse Mathematique, 2007
In this work, we establish certain equivalences between the localisation properties with respect ... more In this work, we establish certain equivalences between the localisation properties with respect to spherical Fourier means of the support of a given Borel measure and the L 2-rate of decay of the Fourier extension operator associated to it. This, in turn, is intimately connected with the property that the X-ray transform of the measure be uniformly bounded. Geometric properties of sets supporting such a measure are studied.
In this work we improve our result in . We prove a strong-type almost-orthogonality principle for... more In this work we improve our result in . We prove a strong-type almost-orthogonality principle for maximal functions along several directions. We use geometric methods and a covering lemma.
In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, o... more In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, on the weak-type norm of a maximal operator associated with an arbitrary collection of directions in the plane. The proof relies upon a geometric argument and on induction with respect to the number of directions. Applications are given to estimate the behavior of several types of maximal operators.
In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, o... more In this paper we give a simple proof of a long-standing conjecture, recently proved by N. Katz, on the weak-type norm of a maximal operator associated with an arbitrary collection of directions in the plane. The proof relies upon a geometric argument and on induction with respect to the number of directions. Applications are given to estimate the behavior of several types of maximal operators.
Mathematische Annalen, 2006
We discuss the manner in which one might expect directional maximal functions to control the Four... more We discuss the manner in which one might expect directional maximal functions to control the Fourier extension operator via L 2 weighted inequalities. We prove a general inequality of this type for the extension operator restricted to circles in the plane.
Mathematische Annalen, 2006
We discuss the manner in which one might expect directional maximal functions to control the Four... more We discuss the manner in which one might expect directional maximal functions to control the Fourier extension operator via L 2 weighted inequalities. We prove a general inequality of this type for the extension operator restricted to circles in the plane.
Journal D Analyse Mathematique, 2007
In this work, we establish certain equivalences between the localisation properties with respect ... more In this work, we establish certain equivalences between the localisation properties with respect to spherical Fourier means of the support of a given Borel measure and the L 2-rate of decay of the Fourier extension operator associated to it. This, in turn, is intimately connected with the property that the X-ray transform of the measure be uniformly bounded. Geometric properties of sets supporting such a measure are studied.
Journal D Analyse Mathematique, 2007
In this work, we establish certain equivalences between the localisation properties with respect ... more In this work, we establish certain equivalences between the localisation properties with respect to spherical Fourier means of the support of a given Borel measure and the L 2-rate of decay of the Fourier extension operator associated to it. This, in turn, is intimately connected with the property that the X-ray transform of the measure be uniformly bounded. Geometric properties of sets supporting such a measure are studied.
Deterioro Ambiental. Concepto.-Escrito por Carlos Mota el 06/02/2007