On the existence of (r,g,χ)(r,g,\chi)-cages

In this paper, we work with simple and finite graphs. We study a generalization of the \emph{Cage Problem}, which has been widely studied since cages were introduced by Tutte \cite{T47} in 1947 and after Erd\" os and Sachs \cite{ES63} proved their existence in 1963. An \emph{$(r,g)$-graph} is an $r$-regular graph in which the shortest cycle has length equal to $g$; that is, it is an $r$-regular graph with girth $g$. An \emph{$(r,g)$-cage} is an $(r,g)$-graph with the smallest possible number of vertices among all $(r,g)$-graphs; the order of an $(r,g)$-cage is denoted by $n(r,g)$. The Cage Problem consists of finding $(r,g)$-cages; it is well-known that $(r,g)$-cages have been determined only for very limited sets of parameter pairs $(r, g)$. There exists a simple lower bound for $n(r,g)$, given by Moore and denoted by $n_0(r,g)$. The cages that attain this bound are called \emph{Moore cages}.Comment: 18 page

Eastern Temperate Forests

Human activity in the last century has led to a substantial increase in nitrogen (N) emissions and deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the level of pollution that would be harmful to ecosystems is the critical loads approach. The critical load is dei ned as the level of a pollutant below which no detrimental ecological effect occurs over the long term according to present knowledge. The objective of this project was to synthesize current research relating atmospheric N deposition to effects on terrestrial and aquatic ecosystems in the United States and to identify empirical critical loads for atmospheric N deposition. The receptors that we evaluated included freshwater diatoms, mycorrhizal fungi and other soil microbes, lichens, herbaceous plants, shrubs, and trees. The main responses reported fell into two categories: (1) biogeochemical, and (2) individual species, population, and community responses. The range of critical loads for nutrient N reported for U.S. ecoregions, inland surface waters, and freshwater wetlands is 1 to 39 kg N ha-1 y-1. This broad range spans the range of N deposition observed over most of the country. The empirical critical loads for N tend to increase in the following sequence for different life forms: diatoms, lichens and bryophytes, mycorrhizal fungi, herbaceous plants and shrubs, trees. The critical loads approach is an ecosystem assessment tool with great potential to simplify complex scientii c information and effectively communicate with the policy community and the public. This synthesis represents the i rst comprehensive assessment of empirical critical loads of N for ecoregions across the United States

Estimated losses of plant biodiversity across the U.S. from historical N deposition from 1985—2010.

Although nitrogen (N) deposition is a significant threat to herbaceous plant biodiversity worldwide, it is not a new stressor for many developed regions. Only recently has it become possible to estimate historical impacts nationally for the United States. We used 26 years (1985–2010) of deposition data, with ecosystem-specific functional responses from local field experiments and a national critical loads (CL) database, to generate scenario-based estimates of herbaceous species loss. Here we show that, in scenarios using the low end of the CL range, N deposition exceeded critical loads over 0.38, 6.5, 13.1, 88.6, and 222.1 million ha for the Mediterranean California, North American Desert, Northwestern Forested Mountains, Great Plains, and Eastern Forest ecoregions, respectively, with corresponding species losses ranging from \u3c1% to 30%. When we ran scenarios assuming ecosystems were less sensitive (using a common CL of 10 kg.ha-1.yr-1, and the high end of the CL range) minimal losses were estimated. The large range in projected impacts among scenarios implies uncertainty as to whether current critical loads provide protection to terrestrial plant biodiversity nationally and urge greater research in refining critical loads for U.S. ecosystems

Modos de herencia de la morfología dental en familias Misak del municipio de Silvia (Cauca, Colombia)

This is a cross-sectional descriptive study that identified the pattern of inheritance of 14 Non-metric Dental crown Traits (NDcT) from the frequency, variability, sexual dimorphism, bilateral asymmetry and correspondence between traits, in plaster models obtained from a group of ten families -mother, father and son/ daughter - who are part of the Misak community of Silvia (Cauca, Colombia). For deciduous dentition, Arizona State University Dental Anthropology System (ASUDAS, 1991) was used for crowding, winging and cusp 6, Grine (1986) for Carabelli cusp, Sciuli (1998) for protostylid, deflecting wrinkle, cuspid pattern and number of cusps, and Hanihara (1966) for cusp 7 in deciduous dentition; and for permanent dentition, ASUDAS for the 14 NDCT. High frequencies were observed of protostylid P-point, deflecting wrinkle, cuspid pattern, number of cusps and cusp 6 in deciduous teeth; as well as in permanent teeth crowding, winging, shovel shape, hypocono reduction, protostylid P point, cuspid pattern and cusp 6. There was not sexual dimorphism and bilateral symmetry was observed. There was correspondence between the deciduous teeth and permanent for the expression of the Carabelli cusp, the number of cups and the 6 cusp. It was observed a tendency of the dichotomous presence/absence of the NDCT inheritance from the mothers to the children. According to the NDCT expression and variability the Misak indigenous group corresponds to a population with a considerable influence of the Mongoloid dental complex and a minor influence of Caucasoid and Negroid dental complexes. The absence of sexual dimorphism, the presence of bilateral symmetry, and the correspondence of some traits, evidence a strong genetic control in the inheritance mode (with a tendency from mothers to children) and a low influence of the environment.Este es un estudio descriptivo transversal cuantitativo que identificó el modo de herencia de 14 Rasgos Morfológicos Dentales (RMDC) a partir de la frecuencia, la variablidad, el dimorfismo sexual, la asimetría bilateral y la correspondencia entre rasgos, en modelos de yeso obtenidos de un grupo de diez familias —madre, padre e hijo(a)— que forman parte de la comunidad misak del municipio de Silvia (Cauca, Colombia). Se emplearon los sistemas de registro para dentición decidua Arizona State University Dental Anthropology System (ASUDAS, 1991) para crowding, winging y cúspide 6, Grine (1986) para cúspide de Carabelli, Sciuli (1998) para protostílido, pliegue acodado, patrón cuspídeo y número de cúspides, y Hanihara (1966) para cúspide 7; y para dentición permanente ASUDAS para los 14 RMDC. Se observaron altas frecuencias de punto P del protostílido, pliegue acodado, patrón cuspídeo, número de cúspides y cúspide 6 en los dientes deciduos; y de crowding, winging, forma de pala, reducción de hipocono, punto P del protostílido, patrón cuspídeo y cúspide 6 en los dientes permanentes.No hubo dimorfismo sexual y se observó simetría bilateral. Hubo correspondencia entre la dentición decidua y permanente para la expresión de la cúspide de Carabelli, el número de cúspides y la cúspide 6. Se observó una tendencia de herencia de la expresión dicotómica presencia/ausencia de los RMDC desde las madres hacia los hijos. El grupo de indígenas Misak corresponde a una población con alta influencia del complejo dental mongoloide y baja influencia de los complejos dentales caucasoide y negroide de acuerdo con la expresión y variabilidad de los RMDC. La ausencia de dimorfismo sexual, la presencia de simetría bilateral y la correspondencia de algunos rasgos, evidencia un fuerte control genético en el modo de herencia (con tendencia desde las madres hacia los hijos) y una baja influencia del medio ambiente

A continental analysis of ecosystem vulnerability to atmospheric nitrogen deposition

Atmospheric nitrogen (N) deposition has been shown to decrease plant species richness along regional deposition gradients in Europe and in experimental manipulations. However, the general response of species richness to N deposition across different vegetation types, soil conditions, and climates remains largely unknown even though responses may be contingent on these environmental factors. We assessed the effect of N deposition on herbaceous richness for15,136 forest, woodland, shrubland, and grassland sites across the continental United States, to address how edaphic and climatic conditions altered vulnerability to this stressor. In our dataset, with N deposition ranging from 1 to 19 kg N·ha−1·y−1, we found a unimodal relationship; richness increased at low deposition levels and decreased above 8.7 and 13.4 kg N·ha−1·y−1 in open and closed-canopy vegetation, respectively. N deposition exceeded critical loads for loss of plant species richness in 24% of 15,136 sites examined nationwide. There were negative relationships between species richness and N deposition in 36% of 44 community gradients. Vulnerability to N deposition was consistently higher in more acidic soils whereas the moderating roles of temperature and precipitation varied across scales. We demonstrate here that negative relationships between N deposition and species richness are common, albeit not universal, and that fine-scale processes can moderate vegetation responses to N deposition. Our results highlight the importance of contingent factors when estimating ecosystem vulnerability to N deposition and suggest that N deposition is affecting species richness in forested and nonforested systems across much of the continental United States

La Imagen y la Narrativa como Herramientas para el Abordaje Psicosocial en Escenarios de Violencia. Departamento del Tolima y Bogotá DC.

En el presente trabajo son fruto de la investigación analítica, teórica y práctica, del conflicto armado en Colombia, el cual tiene su propio ciclo de vida, en la creencia autónoma, propagación de las diversas formas de violencias, padecimiento del mismo que se vivió en el área rural y urbana, durante tres periodos que enmarcaron un sinnúmero de acontecimientos que llegaron al punto máximo del terrorismo, intimidaciones y asesinatos, afectando de manera directa a niños (as), jóvenes, adolescentes ya adultos. Las experiencias de sufrimiento entre las víctimas del conflicto armado, permiten crear una comunidad emocional que alienta la recuperación de la persona y se convierte en un vehículo de recomposición cultural y política; ya que el conocer y analizar las diversas situaciones hostiles, nos acerca a la posibilidad de identificarnos con las víctimas, restableciendo los lazos para la acción ciudadana, debido a su contenido moral y a su potencial como instrumento político de descalificación y subordinación. El enfoque narrativo ha logrado un camino reflexivo significativo en los abordajes terapéuticos y psicosociales de violencias sistemáticas, en personas inocentes en enfrentaron la conflagración hasta dentro de sus hogares, como lo expone los Relatos tomados del libro Voces: historias de violencia y esperanza en Colombia. Los cuales refieren hechos violentos en personas que sobrevivieron al conflicto y que hoy en día están detrás del telón, soportando a los impactos psicosociales y traumáticos, con las heridas más profundas, pero en el alma. A lo largo del tiempo, llegados al punto, donde convenir que la realidad no es una foto fija de una situación concreta de lo sucedido, la realidad se va construyendo a medida que va pasando el tiempo teniendo en cuenta el pasado sin perder de vista el futuro. Es claro mencionar, que el sentido de la fotografía, es la magia de las imágenes que hablan y trasmiten emociones y sentimientos, en donde, tan solo una fotografía tiene la facilidad de expresar una historia completa, ya que los sucesos ubicados en las fotografías, en la misma condición del testimonio, pues son el resultado de un momento subjetivo, consecuencia de la vivencia de una experiencia imborrable y en muchos casos incomunicable.In the present work they are the result of analytical, theoretical and practical research of the armed conflict in Colombia, which its own life cycle, in the autonomous belief, propagation of the various forms of violence, suffering from the same that was experienced in the rural and urban areas, during three periods that framed countless events that reached the peak of terrorism, intimidation and murder, directly affecting children, youth, adolescents and adults. The experiences of suffering among the victims of the armed conflict allow the creation of an emotional community that encourages the recovery of the person and becomes a vehicle for cultural and political recomposition; Since knowing and analyzing the various hostile situations brings us closer to the possibility of identifying ourselves with the victims, reestablishing ties for citizen action, due to its moral content and its potential as a political instrument of disqualification and subordination. The narrative approach has achieved a significant reflective path in the therapeutic and psychosocial approaches to systematic violence, in innocent people who faced the conflagration even within their homes, as exposes the Stories taken from the book Voces: stories of violence and hope in Colombia. Which were violent acts in people who survived the conflict and who today are behind the scenes, enduring the psychosocial and traumatic impacts, with the deepest wounds, but in the soul. Over time, at the point where it is agreed that reality is not a still photo of a specific situation of what happened, reality is built as time goes by taking into account the past without losing sight of the future. It is clear to mention that the meaning of photography is the magic of images that speak and convey emotions and feelings, where only a photograph has the facility to express a complete story, since the events located in the photographs, in the same condition of the testimony, since they are the result of a subjective moment, the consequence of the experience of an indelible and in many cases incommunicable experience

Synthesis

Human activity in the last century has led to a substantial increase in nitrogen (N) emissions and deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the level of pollution that would be harmful to ecosystems is the critical loads approach. The critical load is dei ned as the level of a pollutant below which no detrimental ecological effect occurs over the long term according to present knowledge. The objective of this project was to synthesize current research relating atmospheric N deposition to effects on terrestrial and aquatic ecosystems in the United States and to identify empirical critical loads for atmospheric N deposition. The receptors that we evaluated included freshwater diatoms, mycorrhizal fungi and other soil microbes, lichens, herbaceous plants, shrubs, and trees. The main responses reported fell into two categories: (1) biogeochemical, and (2) individual species, population, and community responses. This report synthesizes current research relating atmospheric nitrogen (N) deposition to effects on terrestrial and aquatic ecosystems in the United States and to identify empirical critical loads for atmospheric N deposition. The report evaluates the following receptors: freshwater diatoms, mycorrhizal fungi and other soil microbes, lichens, herbaceous plants, shrubs, and trees. The main responses reported fell into two categories: (1) biogeochemical; and (2) individual species, population, and community responses. The range of critical loads for nutrient N reported for U.S. ecoregions, inland surface waters, and freshwater wetlands is 1 to 39 kg N ha-1 y-1. This range spans the range of N deposition observed over most of the country. The empirical critical loads for N tend to increase in the following sequence for different life forms: diatoms, lichens and bryophytes, mycorrhizal fungi, herbaceous plants and shrubs, trees

Synthesis

Human activity in the last century has led to a substantial increase in nitrogen (N) emissions and deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the level of pollution that would be harmful to ecosystems is the critical loads approach. The critical load is dei ned as the level of a pollutant below which no detrimental ecological effect occurs over the long term according to present knowledge. The objective of this project was to synthesize current research relating atmospheric N deposition to effects on terrestrial and aquatic ecosystems in the United States and to identify empirical critical loads for atmospheric N deposition. The receptors that we evaluated included freshwater diatoms, mycorrhizal fungi and other soil microbes, lichens, herbaceous plants, shrubs, and trees. The main responses reported fell into two categories: (1) biogeochemical, and (2) individual species, population, and community responses. This report synthesizes current research relating atmospheric nitrogen (N) deposition to effects on terrestrial and aquatic ecosystems in the United States and to identify empirical critical loads for atmospheric N deposition. The report evaluates the following receptors: freshwater diatoms, mycorrhizal fungi and other soil microbes, lichens, herbaceous plants, shrubs, and trees. The main responses reported fell into two categories: (1) biogeochemical; and (2) individual species, population, and community responses. The range of critical loads for nutrient N reported for U.S. ecoregions, inland surface waters, and freshwater wetlands is 1 to 39 kg N ha-1 y-1. This range spans the range of N deposition observed over most of the country. The empirical critical loads for N tend to increase in the following sequence for different life forms: diatoms, lichens and bryophytes, mycorrhizal fungi, herbaceous plants and shrubs, trees

Conditional vulnerability of plant diversity to atmospheric nitrogen deposition across the United States

Atmospheric nitrogen (N) deposition has been shown to decrease plant species richness along regional deposition gradients in Europe and in experimental manipulations. However, the general response of species richness to N deposition across different vegetation types, soil conditions, and climates remains largely unknown even though responses may be contingent on these environmental factors. We assessed the effect of N deposition on herbaceous richness for 15,136 forest, woodland, shrubland, and grassland sites across the continental United States, to address how edaphic and climatic conditions altered vulnerability to this stressor. In our dataset, with N deposition ranging from 1 to 19 kg N⋅ha−1⋅y−1, we found a unimodal relationship; richness increased at low deposition levels and decreased above 8.7 and 13.4 kg N⋅ha−1⋅y−1 in open and closed-canopy vegetation, respectively. N deposition exceeded critical loads for loss of plant species richness in 24% of 15,136 sites examined nationwide. There were negative relationships between species richness and N deposition in 36% of 44 community gradients. Vulnerability to N deposition was consistently higher in more acidic soils whereas the moderating roles of temperature and precipitation varied across scales. We demonstrate here that negative relationships between N deposition and species richness are common, albeit not universal, and that fine-scale processes can moderate vegetation responses to N deposition. Our results highlight the importance of contingent factors when estimating ecosystem vulnerability to N deposition and suggest that N deposition is affecting species richness in forested and nonforested systems across much of the continental United States

Glomerulonefritis ANCA asociada con biopsia renal atípica en paciente con artritis psoriásica

Introducción: La glomerulonefritis rápidamente progresiva (GNRP) no se presenta como manifestación extraarticular de la Artritis Psoriasica (APs). Las GNRP son frecuentemente relacionadas a vasculitis ANCA asociadas (VAA). Según la bibliografía, no es inusual encontrar depósitos de inmunocomplejos (IC) en las lesiones glomerulares de VAA. Existen publicaciones de casos en donde la presencia de una VAA podría estar asociada a la terapia con anti-TNFα. Caso: Mujer de 56 años de edad con artritis psoriásica en tratamiento con metotrexato y etanercept. Debido a infección de vías aéreas suspende etanercept y, posterior a la suspensión, evoluciona con síndrome nefrítico con biopsia renal que evidencia GN con depósitos de IC poco característicos y ANCA c / PR3 (+) en altos títulos. Conclusiones: Presentamos una paciente en la cual la manifestación de dos entidades, aparentemente no relacionadas, representa un reto diagnóstico y terapéutico. La relación con el tratamiento anti-TNFα ha sido descripta, aunque no pueda demostrarse su relación causal. La mayoría de las biopsias renales de las VAA no presentan depósitos inmunes en la IF; aunque en un porcentaje bajo pueden visualizarse grados variables de complemento e inmunocomplejos