Desingularization of semialgebraic sets. Applications

Hironaka's resolution of singularities is a celebrated discipline that has many applications in many areas of Mathematics. In this work we approach the desingularization of semialgebraic sets ${\mathcal S}\subset{\mathbb R}^n$. We prove the counterpart to `Hironaka's desingularization of real algebraic sets' in the semialgebraic setting. It involves Nash manifolds with corners instead of non-singular real algebraic sets. The obtained results are optimal when ${\mathcal S}$ is a closed semialgebraic set. The main tools involved are: Hironaka's desingularization of real algebraic sets, Hironaka's embedded desingularization of real algebraic subsets of non-singular real algebraic sets and drilling blow-ups of Nash manifolds with centers closed Nash submanifolds. We show how to `build' a Nash manifold with corners ${\mathcal Q}\subset{\mathbb R}^n$ from a suitable Nash manifold $M\subset{\mathbb R}^n$ (of its same dimension), which contains ${\mathcal Q}$ as a closed subset, by folding $M$ along the irreducible components of a normal-crossings divisor of $M$, which is the smallest Nash subset of $M$ that contains the boundary $\partial{\mathcal Q}$ of ${\mathcal Q}$. One can choose as the Nash manifold $M$ the Nash `double' $D({\mathcal Q})$ of ${\mathcal Q}$, which is analogous to the Nash double of a Nash manifold with boundary, but $D({\mathcal Q})$ takes into account the peculiarities of the boundary of a Nash manifold with corners. We include several applications: (1) Weak desingularization of closed semialgebraic sets using Nash manifolds with boundary, (2) Representation of compact semialgebraic sets connected by analytic paths as images under Nash maps of closed unit balls, (3) Construction of Nash models for compact orientable smooth surfaces of genus $g\geq0$, and (4) Nash approximation of continuous semialgebraic maps whose target spaces are Nash manifolds with corners.Comment: 57 pages, 7 figures, 1 tabl

Surjective Nash maps between semialgebraic sets

In this work we study the existence of surjective Nash maps between two given semialgebraic sets ${\mathcal S}$ and ${\mathcal T}$. Some key ingredients are: the irreducible components ${\mathcal S}_i^*$ of ${\mathcal S}$ (and their intersections), the analytic-path connected components ${\mathcal T}_j$ of ${\mathcal T}$ (and their intersections) and the relations between dimensions of the semialgebraic sets ${\mathcal S}_i^*$ and ${\mathcal T}_j$. A first step to approach the previous problem is the former characterization done by the second author of the images of affine spaces under Nash maps. The core result of this article to obtain a criterion to decide about the existence of surjective Nash maps between two semialgebraic sets is: {\em a full characterization of the semialgebraic subsets ${\mathcal S}\subset{\mathbb R}^n$ that are the image of the closed unit ball $\overline{\mathcal B}_m$ of ${\mathbb R}^m$ centered at the origin under a Nash map $f:{\mathbb R}^m\to{\mathbb R}^n$}. The necessary and sufficient conditions that must satisfy such a semialgebraic set ${\mathcal S}$ are: {\em it is compact, connected by analytic paths and has dimension $d\leq m$}. Two remarkable consequences of the latter result are the following: (1) {\em pure dimensional compact irreducible arc-symmetric semialgebraic sets of dimension $d$ are Nash images of $\overline{\mathcal B}_d$}, and (2) {\em compact semialgebraic sets of dimension $d$ are projections of non-singular algebraic sets of dimension $d$ whose connected components are Nash diffeomorphic to spheres (maybe of different dimensions)}.Comment: 41 pages, 8 figure

O aluno com altas habilidades/superdotação em escola ribeirinha na Amazônia

In this study we investigated the student with high skills/giftedness in a riverside School in Amapá’s Amazon with possibility of inclusion in school? A research based on the qualitative approach was conducted, from the following problem question: How has the inclusion of a student with high skills/giftedness at a riverside school in the city of Mazagão in the state of Amapá been taking place? The study aimed to analyze the inclusion process of students with high skills/giftedness from the 1st to the 5th grade of elementary School. The locus of the research was a riverside school located in the municipality of Mazagão in the state of Amapá. For data collection, semi-structured interviews, observation and photographic recording were performed. The participants of this research were a teacher of the student's class with high skills/giftedness, a teacher of specialized educational attendance, a student with high skills/giftedness, a pedagogical coordinator and the school principal. The collected data was analyzed from the definition of the Aprioristic Category: school inclusion, as well as other intermediate categories and final categories that, in the case, are the non-aprioristic ones that emerged from the theoretical framework adopted in the research and Empirical research. As a result, this study brings significant theoretical and practical contributions to the process of inclusion of students with high skills/giftedness in this riverside School in the Amapá’s Amazon. The results showed that there are difficulties in the process of inclusion of this public related to various aspects such as the formation of teachers and of the entire school team, infrastructure, the organization of classrooms, among others, as well as, demonstrate the importance of research in this universe to strengthen theoretical-practical questions related to inclusion.Neste estudo investigou-se a inclusão de um aluno com altas habilidades/superdotação em escola ribeirinha na Amazônia Amapaense. Para tanto realizou-se uma pesquisa baseada na abordagem qualitativa, a partir da seguinte questão de pesquisa: Como tem se dado a inclusão escolar de um aluno com altas habilidades/superdotação em uma escola ribeirinha no município de Mazagão no Estado do Amapá? A pesquisa teve como objetivo geral analisar o processo de inclusão de alunos com altas habilidades/superdotação do 1º ao 5º ano do Ensino Fundamental. O lócus da pesquisa foi uma Escola ribeirinha localizada no município de Mazagão no Estado do Amapá. Para a coleta dos dados foram realizadas entrevistas semiestruturadas, observação e registro fotográfico. Os participantes da referida pesquisa foram um professor da turma do aluno com altas habilidades/superdotação, um professor do Atendimento Educacional Especializado, um aluno com altas habilidades/ /superdotação, um coordenador pedagógico e o diretor da escola. Os dados coletados foram analisados a partir da análise de conteúdo, considerando a definição da categoria apriorística: inclusão escolar, assim como outras categorias intermediárias e categorias finais que no caso são as não apriorísticas que emergiram do referencial teórico adotado na pesquisa e da investigação empírica. Os resultados apontaram que existem dificuldades, no processo de inclusão deste público, relacionadas a vários aspectos como a formação de professores e de toda equipe escolar, de infraestrutura, de organização das salas de aula, entre outros, bem como, demonstraram a importância de pesquisas neste universo para o fortalecimento de questões teórico-práticas relativas à inclusão

Senescence of flag leaves and ears of wheat hastened by methyl jasmonate

Fil: Beltrano, José. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Ronco, Marta Guillermina. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Montaldi, Edgardo. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Carbone, Alejandra. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin

A solution for strong authentication in sensor-based healthcare environments / Uma solução de autenticação forte para ambientes de saúde baseados em sensores

Medical devices equipped with network interfaces, classified as sensors, transmit sensitive information over the network. This information need to be secured applying security mechaninsms, in order to mitigate vulnerabilities.  Because  of the vulnerabilities, strong means of authentication have been investigated. However, existing strong authentication solutions require user interaction, not respecting their individuality. This paper proposes a strong authentication solution on sensor-based healthcare environments in order to support the authentication process of patients with special needs. The authentication was based on a combination of two methods acquired from sensors  of a healthcare environment: biometrics and location. In addition, standardizations provided by ISO/IEC 27799 and SBIS was followed for a safe development.

Emission of water stress ethylene in wheat (Triticum aestivum L.) ears : Effects of rewatering

In this work it has been found that ethylene production increased only slightly under conditions of a moderate or severe water stress. However, the rehydration of the plants at full turgor after desiccation caused a high emission of ethylene. The desiccation would not irreversibly inactivate the enzymes of the ethylene pathway, since rehydration made the synthesis recommence almost immediately. Water deficit also increased the free radical levels and the antioxidant scavengers, such as superoxide dismutase. Free radicals promote the conversion of 1-amino-cyclopropane-1-carboxylic acid to ethylene, then it is logical to think that both chemical species are involved in the phenomenon of the acceleration of the grain maturity before the plant collapses.Instituto de Fisiología Vegeta

UNA MIRADA SOBRE LA INVESTIGACIÓN EN LA UNIVERSIDAD NACIONAL DE MAR DEL PLATA

Las expectativas de este trabajo están centradas en el conocimiento del desarrollo de la investigación en la UNMDP, los recursos disponibles para cumplir con los objetivos propuestos y su estado actual. Para ello se procedió a la recolección y el análisis de datos, fundamentalmente los correspondientes a esta última década. Una observación importante, que define el campo de análisis de la información expuesta en este trabajo, es que sólo se tienen en cuenta los aspectos de la investigación que promueve o fomenta la UNMDP, (proyectos, subsidios, becas, etc), sin considerar el aporte de otras instituciones u organizaciones que ayudan considerablemente al desarrollo de la ciencia en la Universidad, como el CONICET, o las agencias de cooperación internacional, por ejemplo. En este trabajo se han seleccionado algunos aspectos fundamentales del desarrollo de la investigación, unos por lo reveladores que resultan en la observación general, otros por ser los que reúnen una mayor confiabilidad en sus datos. Así aparecen: la evolución histórica, el sistema organizativo, los proyectos de investigación, las becas, los fondos para la investigación, la producción científica y el impacto de la investigación en la docencia. Se intenta de este modo perfilar a la UNMDP con indicadores que permitan, en breve, conformar un verdadero proceso de autoevaluación y su comparación con Instituciones similares. La investigación en la UNMDP posee historia y tiene presencia en su continuo hacer. Hoy es posible concebir a la trilogía docencia - investigación - extensión como síntesis de la finalidad que le cabe como Institución. Podrán cambiar los mecanismos de financiamiento, los objetos de la investigación, las estructuras organizativas y los planes de formación y estímulo de los recursos humanos, pero no se puede dejar de pensar en la investigación como una función primordial de la Universidad, creando conocimiento, y especialmente aquel conocimiento que tienda a resolver los problemas que el medio requiere. De lo presentado y analizado podría deducirse que esta Universidad está, en esta década tendiendo a encontrar sus propias dimensiones en el campo de la investigación: el número de proyectos se ha estabilizado, también los recursos y las cantidades de becas, existe una marcada presencia de las Facultades de Ingeniería, Humanidades, Cs. Exactas y Naturales, Cs. Agrarias y Arquitectura por sobre las demás, se tiende lentamente a incrementar la dedicación de sus docentes, se fomenta su formación a nivel cuaternario, se establecen convenios que permitan el intercambio y la cooperación y, así, tantas otras actividades que remarcan la intención de integrar la investigación al quehacer de nuestra Universidad. Queda mucho por hacer. Y, seguramente seguirán marchas y contramarchas, persistiendo el anhelo de que la institución encuentre el modo de concretar el trascendente fin para el que ha sido creada

Physiological responses of wheat grain to pre-treatments with ethylene

El etileno es una hormona que interviene en numerosos procesos, entre ellos, la germinación, maduración y senescencia de flores y frutos. Todos los órganos de las plantas liberan etileno, pero los mayores niveles se registran en flores y frutos, en la etapa de maduración y senescencia. Se determinó que cariopsis de trigo almacenados continúan liberando etileno, aun, con 14% de humedad comercial (0,08 nL ET.g-1.h-1). Son conocidos los efectos ejercidos por el etileno sobre la expansión radial de las células de coleoptilos, lo que trae aparejado una disminución de la longitud y un aumento del diámetro del órgano. El objetivo del presente trabajo fue determinar las respuestas fisiológicas de semillas de trigo sometidas a pretratamientos con etileno. Estos aumentaron la liberación de esta hormona por las semillas, incrementando la tasa de germinación. La elongación de los coleoptilos, y el número y longitud de las raíces disminuyó, pero se incrementó significativamente el diámetro de los primeros. Se infiere que, si bien el efecto sobre las raíces fue detrimental, el menor crecimiento de los coieoptilos y su mayor grosor representan una ventaja para la emergencia de fas plántulas, primordialmente en suelos compactos.Ethylene is a plant hormone that is involved in processes, such as, germination, maturation and senescence of flowers and fruits. All the plant organs produced ethylene and the greatest levels were determined in flowers and fruits during maduration and in the senescence stages. Mature wheat grains release ethylene (0,08 nL ET.g-1.h-1) even with 14% comercial moisture. The effects of the ethylene on the radial expansión of coleoptile cell, length decreasing, and diameter increasing are well known. The aim of this work was to determine the physiological responses of wheat grain subjected to ethylene pretreatments before sowing. Treatments increased the seed ethylene emíssion and germination percentage. Coleoptile eiongation, root number and length decreased, bu! the coleoptile diameter increased significantly. The effect of ethylene on the roots was detrimental, but the reduced coleoptile growth and íneir greater thickness represent an advantaje for the seedíing emergence, mainly in compact soils.Facultad de Ciencias Agrarias y Forestale

Physiological responses of wheat grain to pre-treatments with ethylene

El etileno es una hormona que interviene en numerosos procesos, entre ellos, la germinación, maduración y senescencia de flores y frutos. Todos los órganos de las plantas liberan etileno, pero los mayores niveles se registran en flores y frutos, en la etapa de maduración y senescencia. Se determinó que cariopsis de trigo almacenados continúan liberando etileno, aun, con 14% de humedad comercial (0,08 nL ET.g-1.h-1). Son conocidos los efectos ejercidos por el etileno sobre la expansión radial de las células de coleoptilos, lo que trae aparejado una disminución de la longitud y un aumento del diámetro del órgano. El objetivo del presente trabajo fue determinar las respuestas fisiológicas de semillas de trigo sometidas a pretratamientos con etileno. Estos aumentaron la liberación de esta hormona por las semillas, incrementando la tasa de germinación. La elongación de los coleoptilos, y el número y longitud de las raíces disminuyó, pero se incrementó significativamente el diámetro de los primeros. Se infiere que, si bien el efecto sobre las raíces fue detrimental, el menor crecimiento de los coieoptilos y su mayor grosor representan una ventaja para la emergencia de fas plántulas, primordialmente en suelos compactos.Ethylene is a plant hormone that is involved in processes, such as, germination, maturation and senescence of flowers and fruits. All the plant organs produced ethylene and the greatest levels were determined in flowers and fruits during maduration and in the senescence stages. Mature wheat grains release ethylene (0,08 nL ET.g-1.h-1) even with 14% comercial moisture. The effects of the ethylene on the radial expansión of coleoptile cell, length decreasing, and diameter increasing are well known. The aim of this work was to determine the physiological responses of wheat grain subjected to ethylene pretreatments before sowing. Treatments increased the seed ethylene emíssion and germination percentage. Coleoptile eiongation, root number and length decreased, bu! the coleoptile diameter increased significantly. The effect of ethylene on the roots was detrimental, but the reduced coleoptile growth and íneir greater thickness represent an advantaje for the seedíing emergence, mainly in compact soils.Facultad de Ciencias Agrarias y Forestale