Systematic Revision of Elaphoglossum (Dryopteridaceae) in French Polynesia, with the Description of Three New Species

Species descriptions and a key for the nine species of Elaphoglossum (Dryopteridaceae) in French Polynesia are provided. Three new species are described: E. austromarquesense from the southern Marquesas Islands, E. florencei from Raiatea and Moorea, and E. meyeri from Rapa. Each species is illustrated by a line drawing of the habit, and spore images using a scanning electron microscope. Images of scales, one of the most important diagnostic characters in the genus, are also included. © 2008 The Linnean Society of London

Human-Mediated Emergence as a Weed and Invasive Radiation in the Wild of the CD Genome Allotetraploid Rice Species (Oryza, Poaceae) in the Neotropics

BACKGROUND: The genus Oryza is being used as a model in plant genomic studies although there are several issues still to be resolved regarding the spatio-temporal evolution of this ancient genus. Particularly contentious is whether undated transoceanic natural dispersal or recent human interference has been the principal agent determining its present distribution and differentiation. In this context, we studied the origin and distribution history of the allotetraploid CD rice genome. It is endemic to the Neotropics but the genus is thought to have originated in the Paleotropics, and there is relatively little genetic divergence between some orthologous sequences of the C genome component and their Old World counterparts. METHODOLOGY/PRINCIPAL FINDINGS: Because of its allotetraploidy, there are several potential pitfalls in trying to date the formation of the CD genome using molecular data and this could lead to erroneous estimates. Therefore, we rather chose to rely on historical evidence to determine whether or not the CD genome was present in the Neotropics before the arrival of Columbus. We searched early collections of herbarium specimens and studied the reports of explorers of the tropical Americas for references to rice. In spite of numerous collectors traveling inland and collecting Oryza, plants determined as CD genome species were not observed away from cultivated rice fields until 1869. Various arguments suggest that they only consisted of weedy forms until that time. CONCLUSIONS/SIGNIFICANCE: The spatio-temporal distribution of herbarium collections fits a simple biogeographical scenario for the emergence in cultivated rice fields followed by radiation in the wild of the CD genome in the Neotropics during the last four centuries. This probably occurred from species introduced to the Americas by humans and we found no evidence that the CD genome pre-existed in the Old World. We therefore propose a new evolutionary hypothesis for such a recent origin of the CD genome. Moreover, we exemplify how an historical approach can provide potentially important information and help to disentangle the timing of evolutionary events in the history of the Oryza genomes

Tunable Porous Organic Crystals: Structural Scope and Adsorption Properties of Nanoporous Steroidal Ureas

Previous work has shown that certain steroidal bis-(N-phenyl)ureas, derived from cholic acid, form crystals in the P61 space group with unusually wide unidimensional pores. A key feature of the nanoporous steroidal urea (NPSU) structure is that groups at either end of the steroid are directed into the channels and may in principle be altered without disturbing the crystal packing. Herein we report an expanded study of this system, which increases the structural variety of NPSUs and also examines their inclusion properties. Nineteen new NPSU crystal structures are described, to add to the six which were previously reported. The materials show wide variations in channel size, shape, and chemical nature. Minimum pore diameters vary from ∼0 up to 13.1 Å, while some of the interior surfaces are markedly corrugated. Several variants possess functional groups positioned in the channels with potential to interact with guest molecules. Inclusion studies were performed using a relatively accessible tris-(N-phenyl)urea. Solvent removal was possible without crystal degradation, and gas adsorption could be demonstrated. Organic molecules ranging from simple aromatics (e.g., aniline and chlorobenzene) to the much larger squalene (Mw = 411) could be adsorbed from the liquid state, while several dyes were taken up from solutions in ether. Some dyes gave dichroic complexes, implying alignment of the chromophores in the NPSU channels. Notably, these complexes were formed by direct adsorption rather than cocrystallization, emphasizing the unusually robust nature of these organic molecular hosts

Spore morphology in relation to phylogeny in the fern genus Elaphoglossum (Dryopteridaceae)

International audienceThe perispore structure of Elaphoglossum was studied using a scanning electron microscope. Of the species examined, 119 corresponded to those used in a previously published phylogenetic analysis of the genus based on two chloroplast noncoding DNA regions, trnL-trnF and rps4-trnS. The spores of 102 additional species were examined for comparative purposes. Five perispore characters were scored for each species and optimized onto the previously published molecular tree. The morphology of the perispore and its character state changes are described and discussed in a phylogenetic context. Synapomorphies for major clades within the genus were identified, such as spines for the Neotropical species of sect. Squamipedia and perforations, spines, and cristae for subsect. Pachyglossa and a large subclade within sect. Setosa. This study is the largest done on perispore morphology in relation to phylogeny in a genus of ferns. Spore images of all species studied are available at http://www.plantsystematics.org

Insights on the March 1998 eruption at Piton de la Fournaise volcano (La Reunion) from microgravity monitoring

We investigate the temporal gravity changes associated with one of the major recent eruptions at Piton de la Fournaise volcano (March 1998) that occurred after an unusual five-year quiet period and initiated a new eruptive cycle. Repeated microgravity surveys allowed us to measure residual gravity changes up to 100 mu Gal within the Enclos Fouque caldera for four months before the start of the eruption. We first analyzed the temporal gravity changes and the height changes, also measured at the gravity benchmarks, on the basis of an intrusive dyke model previously proposed for this eruption from InSAR and tilt data. This analysis reveals that such simple model (finite rectangular shaped tensile dislocation) cannot fit both gravity and geodetic data and leads us to propose a dual source gravity model for this eruption. The gravity data inversion using a genetic algorithm search method allows us to quantify the mass change produced by the intrusive dyke (3.9 to 8.7 x 10(9) kg) and to suggest an additional mass increase at sea level depth (4.6 to 7.2 x 10(10) kg). We interpret the latter as the effect of magma ascent into a reservoir that occurred within the four months before the eruption. We suggest that high concentrations of gas content in the magma reservoir account for a higher compressibility of the intruded magma and produce significant mass change with moderate surface deformation. The 1996 seismic crisis, interpreted as an upward migration of magmatic fluids into a reservoir located at sea level, might support such a hypothesis

Granulomatosis alérgica con presentación inusual

La granulomatosis alérgica es poco frecuente y de causa desconocida. La prostatitis como parte de la extensión de esta enfermedad es rara, sólo existen 12 casos reportados en la literatura. Se presenta un paciente de 26 años de edad, mestizo, con antecedentes de asma bronquial alérgica en la niñez, que en 1993 ingresó por manifestaciones disúricas. Se le detecta tumoración prostática que se concluye histológicamente como prostatitis granulomatosa alérgica. Se comenzó tratamiento con 60 mg de prednisona oral en dosis decrecientes; 1 año después. cuando el mantenimiento es de 5 mg en días alternos, presenta fiebre y aparece eritema nudoso en la porción interna de ambos pies. Se constata eosinofilia periférica y la histología de estos nódulos coincide con la de la próstata, se concluye como una granulomatosis alérgica. Al aumentar la dosis de esteroides desaparecieron completamente las manifestaciones. Se hace una revisión de esta entidad sin encontrar casos de prostatitis como su inicio

Estudio serológico para la detección de anticuerpos contra anaplasma margínale en ganado de lidia mediante la prueba de fijación de complemento en microplaca

La anaplasmosis bovina es una enfermedad hemoparasitaria transmitida por 9arrapatas del género Boophilus spp., moscas, mosquitos hematófagos y Tabanus spp, ampliamente difundida en las zonas tropicales y subtropicales, así como en la altiplanicie de Méxi

Cloned lines of Babesia bovis differ in their ability to induce cerebral babesiosis in cattle

Clones of a Babesia bovis isolate known to cause particularly severe cerebral babesiosis were tested for virulence phenotype by inoculation of cattle. Clones were selected for phenotyping by two criteria – rate of growth in culture and hybridization of a virulence-related probe to Southern blots. Largely on the basis of associated mortality, B. bovis clones were judged to vary in their pathogenic potential