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Search Results: 1 - 10 of 594802 matches for " J. M. VANEGAS-RICO "
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Acta zoológica mexicana , 2010,
Abstract: El nopal Opuntia ficus-indica se cultiva con diversos propósitos en el mundo, mientras que en México, principal productor y consumidor mundial, particularmente se consume como verdura (nopalitos). La producción de nopalitos se ubica, principalmente, en los alrededores de la Ciudad de México donde las cochinillas silvestres Dactylopius spp. son de los insectos más nocivos para el cultivo. El control químico es el método de más uso por los productores, aunque el control biológico podría ser útil para un manejo integrado de plagas. No obstante, los estudios taxonómicos sobre las especies de cochinilla y sus enemigos naturales en México no son abundantes. En esta investigación se planteó conocer las especies presentes de Dactylopius y sus enemigos naturales en Tlalnepantla, Morelos, una de las áreas de mayor producción de nopalitos en México. Se seleccionaron 30 sitios distribuidos en esta región y se establecieron cinco sitios para monitoreo de enemigos naturales cada dos semanas durante un a o. La única especie de cochinilla silvestre del nopal que se encontró correspondió a Dactylopius opuntiae (Cockerell), los enemigos naturales en orden de abundancia fueron Leucopis bellula, Sympherobius barberi, Laetilia coccidivora, Hyperaspis trifurcata, Salpingogaster cochenillivorus, Sympherobius angustus y Chilocorus cacti. Se proporcionan descripciones de biología de los enemigos naturales en campo y laboratorio. Diversos factores relacionados con el manejo del cultivo tuvieron un efecto sobre las poblaciones de D. opuntiae y sus enemigos naturales.
Enemigos naturales de Dactylopius opuntiae (Cockerell) en Opuntia ficus-indica (L.) Miller en el centro de México
Acta zoológica mexicana , 2010,
Abstract: prickly pear, opuntia ficus-indica (l.) miller, is cultivated for many purposes around the world. in mexico, people consume young pads as vegetables and call them "nopalitos". the production of nopalitos occurs mainly around mexico city where cochineal insects (dactylopius spp.) are one of the most important pests. farmers partly control dactylopius using insecticides, but biological control could offer a tool for the integrated pest management. in this paper the cochineal insects and their natural enemies were studied in tlalnepantla, morelos, one of the most important regions for nopalitos production in mexico. in order to determine dactylopius species, 30 samples sites were selected in this region. additionally natural enemies were collected every other week during one year period in five different zones. dactylopius opuntiae (cockerell) was the only cochineal species found in tlalnepantla. the natural enemies, in order of abundance, were leucopis bellula, sympherobius barberi, laetilia coccidivora, hyperaspis trifurcata, salpingogaster cochenillivorus, sympherobius angustus, and chilocorus cacti. we also included some lab and field biology descriptions of these predators. diverse factors of crop management appeared to affect d. opuntiae population and their natural enemies.
Initial value problems in Clifford-type analysis
Yanett M. Bolívar,Carmen J. Vanegas
Mathematics , 2011,
Abstract: We consider an initial value problem of type $$ \frac{\partial u}{\partial t}={\cal F}(t,x,u,\partial_j u), \quad u(0,x)=\phi(x), $$ where $t$ is the time, $x \in \mathbb{R}^n $ and $u_0$ is a Clifford type algebra-valued function satisfying ${\bf D}u=\displaystyle\sum_{j=0}^{n}\lambda_j(x)e_j\partial_ju = 0$, $\lambda_j(x)\in \mathbb{R} $ for all $j$. We will solve this problem using the technique of associated spaces. In order to do that, we give sufficient conditions on the coefficients of the operators ${\cal F}$ and ${\bf D}$, where ${\cal F}(u)= \displaystyle\sum_{i=0}^{n}A^{(i)}(x)\displaystyle\partial_iu$ for $A^{(i)}(x) \in \mathbb{R}$ or $A^{(i)}(x)$ belonging to a Clifford-type algebra, such that these operators are an associated pair.
On the Controllability of a Differential Equation with Delayed and Advanced Arguments
Raúl Manzanilla,Luis Gerardo Mármol,Carmen J. Vanegas
Abstract and Applied Analysis , 2010, DOI: 10.1155/2010/307409
Abstract: A semigroup theory for a differential equation with delayed and advanced arguments is developed, with a detailed description of the infinitesimal generator. This in turn allows to study the exact controllability of the equation, by rewriting it as a classical Cauchy problem. 1. Introduction In this paper, we will study the exact controllability of a functional differential equation with both delayed and advanced arguments. Such equations are often referred to in the literature as mixed-type functional differential equations (MTFDE) or forward-backward equations. The study of this type of equations is less developed compared with other classes of functional equations. Interest in MTDFEs is motivated by problems in optimal control [1] and applications, for example, in economic dynamics [2] and travelling waves in a spatial lattice [3]. See also [4]. In all these references, the reader can find interesting examples and applications. In order to achieve our goal, first, we rewrite the equation as a classical Cauchy problem in a certain Banach space. Then we introduce the associated semigroup and its infinitesimal generator and prove some important properties of these operators (including some spectral properties). This will allow us to characterize the exact controllability, by applying a result of Bárcenas and Diestel (see [5]). 2. Preliminary Results In [6], the following differential-difference equation is considered where and is differentiable in . Equation (2.1) may be written as or equivalently From this we have that in order to find the solution on the interval , it is necessary to know its value on the interval , with being a positive integer. In particular, to determine the solution on the interval , it is necessary to know it on the interval . Accordingly, is defined for as where the function belongs to the space . The solution of the initial value problem (2.1), (2.4) is constructed via an iterative process using the step derivation method. It is where and are constants not all necessarily different from zero. This solution may be extended to the left by rewriting (2.1) as which allows to yield an expression for analogous to (2.5). In order to assure the existence, differentiability, and uniqueness of the solution , it is demanded that must satisfy the relationship for Further, if a differentiable solution exists, then it belongs to the space (see [6, Theorems and ]). Let be the following nonempty, closed subspace of the topological space : The space is endowed with the topology induced by the following countable system of seminorms: The
La participación social en salud: el desafío de Chile
Méndez,Claudio A.; Vanegas López,Jairo J.;
Revista Panamericana de Salud Pública , 2010, DOI: 10.1590/S1020-49892010000200009
Abstract: health care reforms implemented in latin america and the caribbean over the last 20 years have viewed community participation as a system-wide component. nonetheless, these reform efforts have yet to break through the conceptual and operational barriers holding back the development and expansion of community participation. in chile, changes introduced to the health care system are far from achieving any real participation from the community. therefore, the consumer's role needs to be redefined from merely controlling the parts, to reaching across the whole system in a way that consumer input might identify and quickly correct any posible shortcomings in the health system's design, as well as its operations. with this in mind, the main challenges are to strengthen coordination among the various promotion and participation commitments, as well as community control, and to generate data and other evidence to assess the impact of community participation in health strategies.
Education and Health: Epidemiological Indicators Can Improve the Continuing Education Process  [PDF]
Érico Faustini, Claus D. Stobäus, Juan J. M. Mosquera
Creative Education (CE) , 2014, DOI: 10.4236/ce.2014.521209
Abstract: In the field of Health Education, understanding human development is essential, taking into account a set of actions that can promote the protection and care to a better child development, so we researched about the evolution in epidemiological indicators related to child development, through literature review and systematic data collected on public system, in Rio Grande do Sul, a state in south Brazil. For this, we do a review that brought together elements of updated on epidemiological and social indicators: changes in the understanding of the processes health and disease, various public health policies that influence personal and social behaviors, especially for parents and caregivers of children. The findings allow seeing that data about child with low birth weight are inversely proportional to the number of years of parents study, mainly from 8 years of schooling; that actions of Health Education can be aimed at doctors, caregivers and pregnant; and that reference systems ensure correct referrals. As ultimate implications, we suggest public policies that enable reduce neonatal mortality by investing in access more the formal Education, encouraging at least the completion of elementary education. We can also encourage medical continuing processes that can observe continually the data that are contained in several public data systems.
Esclerosis múltiple en una mujer fallecida por quemaduras en el incendio del domicilio Multiple sclerosis in a woman died by burns in a house fire
J. Lucena,M. Salguero,A. Rico,M. Blanco
Cuadernos de Medicina Forense , 2004,
Abstract: La esclerosis múltiple (EM) o esclerosis en placas es la más común de las enfermedades inflamatorias desmielinizantes del SNC y el trastorno neurológico más incapacitante en los adultos jóvenes. Se caracteriza por la aparición de lesiones focales diseminadas en la sustancia blanca denominadas placas en las que lo más llamativo es la pérdida de la mielina (desmielinización) con preservación relativa de los axones. Es infrecuente que esta enfermedad entre en el campo de investigación médico-forense, ya que, habitualmente, está bien diagnosticada clínicamente y en caso de tener interés la confirmación del diagnóstico post-mortem se realizaría una autopsia clínica. Presentamos los hallazgos neuropatológicos de una mujer de 47 a os, en situación de invalidez (silla de ruedas) por una EM de 17 a os de evolución, que fallece como consecuencia de las quemaduras producidas por un incendio en el domicilio. The multiple sclerosis (MS) or plaque sclerosis is the most frequent of the inflammatory demyelinating diseases of the SNC and the most incapacitating neurological disorder in young adults. It is characterized by the presence of focal an scattered lesions in the white matter called plaques in which the hallmark is the loss of myelin (demyelination) with the preservation of axons. It is uncommon that this disorder enters in the medico-legal field because, in general, has a very good clinical diagnosis and in case of interest to confirm the post-mortem diagnosis a clinical autopsy would be performed. We present the neuropathological findings of a woman aged 47 years, handicapped (wheel's chair) due to MS with a progression of 17 years, who died by burns in a house fire.
Embolia grasa como complicación de politraumatismo por precipitación autolítica Fat embolism as complication of polytraumatism by suicide jumping
J. Lucena,M. Salguero,A. Rico,M. Blanco
Cuadernos de Medicina Forense , 2005,
Abstract: El síndrome de embolia grasa (SEG) es un cuadro clínico debido a la oclusión de los vasos sanguíneos por glóbulos de grasa. Se asocia fundamentalmente a fracturas de los huesos largos y es una importante fuente de morbilidad y mortalidad en pacientes politraumatizados. Aunque las primeras descripciones se realizaron a finales del siglo XIX en la actualidad sigue siendo un desafío para el clínico por lo que, en ocasiones, el diagnóstico inicial se realiza en la autopsia. Presentamos un caso de SEG en una mujer de 19 a os que fallece en el hospital doce días después de precipitarse desde un puente con finalidad suicida sufriendo politraumatismo con fractura de huesos largos. El SEG fue sospechado clínicamente y se diagnosticó en la autopsia macroscópica siendo posteriormente confirmado por los estudios histopatológicos. Así mismo se revisan las características clinico-patológicas del SEG. Fat embolism syndrome (FES) is a clinical entity which consists in the occlusion of blood vessels by fat droplets. It is commonly associated to long bone fractures and it's an important source of morbidity and mortality in polytraumatized patients. Although the first descriptions were made in the nineteenth century, nowadays it continues to be an important clinical challenge determining that, sometimes, the first diagnostic is made at autopsy. In this paper, we present a case of FES in a woman 19 years old who died in hospital twelve days after jumping from a bridge suffering polytraumatism with long bone fracture. FES was suspected clinically and diagnosed in the gross autopsy being confirmed microscopically. The clinic-pathological characteristics of this syndrome are also reviewed.
Miocardiopatía hipertrófica como causa de muerte súbita en una mujer joven Hypertrophic cardiomyopathy presenting as sudden death in a young woman
A. Rico,J. Lucena,M. Salguero,M. Blanco
Cuadernos de Medicina Forense , 2007,
Abstract: La miocardiopatía hipertrófica (MCH) es una enfermedad genética muy heterogénea, con múltiples loci, identificándose para cada gen múltiples mutaciones. Está considerada en Estados Unidos la causa más frecuente de muerte súbita (MS) en jóvenes, fundamentalmente atletas, siendo en ocasiones la primera manifestación de la enfermedad. La MCH se caracteriza morfológicamente por una hipertrofia asimétrica del ventrículo izquierdo y/o derecho con un patrón histopatológico caracterizado por desestructuración ("disarray") de los miocardiocitos en una matriz de tejido conectivo prominente así como hipertrofia de la íntima de las arterias coronarias intramurales. Se expone el caso de una mujer joven, de 25 a os, diagnosticada clínicamente y con antecedentes familiares de MS por MCH en su madre, que presentó una MS mientras dormía. Hypertrophic cardiomyopathy (HCM) is a genetic and very heterogeneous disease with multiple loci, and with several mutations identified for every gene. In USA, it is regarded as the most common cause of sudden death (SD) in young people (mainly athletes), and occasionally SD is the initial presentation of the disease. HCM is morphologically characterized by an asymmetric hypertrophy of left and/or right ventricle with a histopathological pattern of cardiac myocytes dearrangement in a prominent connective tissue matrix, as well as intimal hypertrophy of intramural coronary arteries. In this paper, we present the case of a 25 year-old woman, clinically diagnosed with HCM, and with family history of HCM in her mother, who experienced a SD while sleeping.
The flavor of neutrinos in muon decays at a neutrino factory and the LSND puzzle
A. Bueno,M. Campanelli,M. Laveder,J. Rico,A. Rubbia
Physics , 2000, DOI: 10.1088/1126-6708/2001/06/032
Abstract: The accurate prediction of the neutrino beam produced in muon decays and the absence of opposite helicity contamination for a particular neutrino flavor make a future neutrino factory the ideal place to look for the lepton flavor violating (LFV) decays of the kind $\mu^+\ra e^+\nuebar\numu$ and lepton number violating (LNV) processes like $\mu^-\ra e^-\nue\numu$. Excellent sensitivities can be achieved using a detector capable of muon and/or electron identification with charge discrimination. This would allow to set experimental limits that improve current ones by more than two orders of magnitude and test the hypothesis that the LSND excess is due to such anomalous decays, rather than neutrino flavor oscillations in vacuum.
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