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The removal of copper ions, from synthetic solutions, using walnut shell and olive pomace waste as biosorbents was studied. Synthetic copper solutions were used, and the contact time, initial pH, biosorbent dose, and initial concentration of copper ions were evaluated. The used particle size of both biosorbents was inferior to 600 µm. In the elimination of copper ions, the walnut shell reached 88% (30 min), and the olive pomace 86.5% (40 min). The maximum removal of copper ions was at pH 5 with both biosorbents. The elimination of copper ions was constant with increasing doses of bio-sorbent; however, a decrease close to 90% in the biosorption capacity was determined, when the dose of biosorbent increased from 1 to 10 g/L. The effect of the biosorption capacity increased proportionally with the initial concentration of copper ions; achieving biosorption of 8.3 and 12.9 mg of Cu+2/g of biosorbent, with walnut shell and olive pomace, respectively. Both biosorbent allowed copper ions removal close to 90%; however, to the olive pomace was not necessary a size reduction and had a higher copper ions biosorption capacity than the walnut shell.

RESUMEN: Se estudió la remoción de iones cobre desde solución sintética, usando cáscara de nuez y orujo de oliva como biosorbentes; se evaluó el tiempo de contacto, pH inicial, dosis de biosorbente y concentración inicial de iones cobre. El tamaño de partícula usado de ambos biosorbentes fue inferior a 600 µm. En la eliminación de iones cobre, la cáscara de nuez alcanzó 88 % (30 min) y el orujo de oliva 86,5 % (40 min). La máxima remoción de iones cobre fue a pH 5 con ambos biosorbentes. La eliminación de iones cobre fue constante con dosis crecientes de biosorbente; pero, se determinó una disminución cercana al 90 % en la capacidad de biosorción, cuando la dosis de biosorbente incrementó de 1 a 10 g/L. El efecto de la capacidad de biosorción aumentó proporcionalmente con la concentración inicial de iones cobre; obteniéndose biosorción de 8,3 y 12,9 mg de Cu+2/g de biosorbente, con cáscara de nuez y orujo de oliva, respectivamente. Ambos biosorbentes permitieron una remoción de iones cobre cercana al 90%; sin embargo, el orujo de oliva no necesitó reducción de tamaño y tuvo mejor capacidad de biosorción de iones cobre que la cáscara de nuez.

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Loss of genetic diversity reduces the ability of species to evolve and respond to environmental change. Araucaria araucana is an emblematic conifer species from southern South America, with important ethnic value for the Mapuche people (Pehuenche); the Chilean Government has catalogued its conservation status as vulnerable. Climatic fluctuations were potentially a major impact in the genetic variation within many tree species. In this context, the restricted geographic distribution of A. araucana in Chile appears to be a consequence of the Last Glacial Maximum (LGM). During the past two centuries, strong human intervention has also affected the geographical distribution and population sizes of A. araucana. Reduction of population size may cause loss of genetic diversity, which could affect frequency of adaptive loci. The aims of this study were to know the existence of potential loci under selection and populations with genetic, demographic disequilibrium in the Chilean distribution of A. araucana. Based on 268 polymorphic AFLP loci, we have investigated potential loci under selection and genetic, demographic disequilibrium within seven Chilean populations of Araucaria araucana. Correlation of 41 outlier loci with the environmental variables of precipitation and temperature reveals signatures of selection, whereas 227 neutral loci provide estimates of demographic equilibrium and genetic population structure. Three populations are recommended as priorities for conservation.

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Adaptive radiation is a common evolutionary phenomenon in oceanic islands. From one successful immigrant population, dispersal into different island environments and directional selection can rapidly yield a series of morphologically distinct species, each adapted to its own particular environment. Not all island immigrants, however, follow this evolutionary pathway. Others successfully arrive and establish viable populations, but they remain in the same ecological zone and only slowly diverge over millions of years. This transformational speciation, or anagenesis, is also common in oceanic archipelagos. The critical question is why do some groups radiate adaptively and others not? The Juan Fernández Islands contain 105 endemic taxa of angiosperms, 49% of which have originated by adaptive radiation (cladogenesis) and 51% by anagenesis, hence providing an opportunity to examine characteristics of taxa that have undergone both types of speciation in the same general island environment. Life form, dispersal mode, and total number of species in progenitors (genera) of endemic angiosperms in the archipelago were investigated from literature sources and compared with modes of speciation (cladogenesis vs. anagenesis). It is suggested that immigrants tending to undergo adaptive radiation are herbaceous perennial herbs, with leaky self-incompatible breeding systems, good intra-island dispersal capabilities, and flexible structural and physiological systems. Perhaps more importantly, the progenitors of adaptively radiated groups in islands are those that have already been successful in adaptations to different environments in source areas, and which have also undergone eco-geographic speciation. Evolutionary success via adaptive radiation in oceanic islands, therefore, is less a novel feature of island lineages but rather a continuation of tendency for successful adaptive speciation in lineages of continental source regions.

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This study analyses and compares the genetic signatures of anagenetic and cladogenetic speciation in six species of the genus Robinsonia (Asteraceae, Senecioneae), endemic to the Juan Fernández Islands, Chile. Population genetic structure was analyzed by amplified fragment length polymorphism (AFLP) and microsatellite (simple sequence repeat, SSR) markers from 286 and 320 individuals, respectively, in 28 populations. Each species is genetically distinct. Previous hypotheses of classification among these species into subgenera and sections, via morphological, phytochemical, isozymic and internal transcribed spacer (ITS) data, have been confirmed, except that R. saxatilis appears to be related to R. gayana rather than R. evenia. Analysis of phylogenetic results and biogeographic context suggests that five of these species have originated by cladogenesis and adaptive radiation on the older Robinson Crusoe Island. The sixth species, R. masafuerae, restricted to the younger Alejandro Selkirk Island, is closely related to and an anagenetic derivative of R. evenia from Robinson Crusoe. Microsatellite and AFLP data reveal considerable genetic variation among the cladogenetically derived species of Robinsonia, but within each the genetic variation is lower, highlighting presumptive genetic isolation and rapid radiation. The anagenetically derived R. masafuerae harbors a level of genetic variation similar to that of its progenitor, R. evenia. This is the first direct comparison of the genetic consequences of anagenetic and cladogenetic speciation in plants of an oceanic archipelago.

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A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity. We investigate speciation in Drimys confertifolia, endemic to the two major islands of the Juan Fernández Archipelago, Chile, to determine genetic consequences of anagenesis, to examine relationships among populations of D. confertifolia and the continental species D. winteri and D. andina, and to test probable migration routes between the major islands. Population genetic analyses were conducted using AFLPs and nuclear microsatellites of 421 individuals from 42 populations from the Juan Fernández islands and the continent. Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor. The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape. Analysis of the probability of migration within the archipelago confirms colonization from the older island, Robinson Crusoe, to the younger island Alejandro Selkirk.

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PREMISE OF THE STUDY: Anagenesis (or phyletic evolution) is one mode of speciation that occurs in the evolution of plants on oceanic islands. Of two endemic species on the Juan Fernández Islands (Chile), Myrceugenia fernandeziana and M. schulzei (Myrtaceae), believed to have originated anagenetically from different continental progenitors, the first is endemic to Robinson Crusoe Island and has no clear tie to continental relatives; the last is endemic to the younger island, Alejandro Selkirk Island, and has close affinity to M. colchaguensis in mainland Chile. METHODS: Using AFLPs and six nuclear microsatellites from 381 individuals representing 33 populations, we determined patterns of genetic variation within and among populations on both islands and between those of the islands and mainland. KEY RESULTS: Considerable genetic variation was found within populations on both islands. The level of gene diversity within M. schulzei was equivalent to that of its close continental relative M. colchaguensis. Genetic diversity was not partitioned geographically in M. fernandeziana and was weakly so and nonsignificantly in M. schulzei. CONCLUSIONS: The high genetic variation in both taxa is most likely due to anagenetic speciation. Subsidence of the older island Robinson Crusoe, landscape erosion, and restructuring of communities have severely reduced the overall island population to a single panmictic system. On the younger and less modified Alejandro Selkirk Island, slightly stronger patterns of genetic divergence are seen in M. schulzei. Because both species are genetically diverse and number in the thousands of individuals, neither is presently endangered in the archipelago.

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Ten microsatellite markers were developed for Robinsonia (Asteraceae), a genus endemic to the Juan Fernández Archipelago, Chile. Polymorphisms of these markers were tested using one population each of R. evenia, R. gayana, and R. gracilis. The number of alleles for these markers ranged from 2 to 17 per locus, and expected heterozygosity ranged from 0 to 0.847 by population. A significant deviation from Hardy-Weinberg equilibrium was observed in zero to two markers in each population, and no significant linkage disequilibrium between markers was detected. The markers reported here would be useful for evolutionary studies and conservation strategies in Robinsonia.

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PREMISE OF THE STUDY: Microsatellite markers were developed in Erigeron rupicola and tested by amplification in six Erigeron species endemic to the Juan Fernández Archipelago, Chile, to investigate genetic diversity and population structure. • METHODS AND RESULTS: Using 454 pyrosequencing, 24 primer pairs were developed in E. rupicola, 12 of which amplified and presented polymorphism among endemic species of Erigeron in the Archipelago. Two populations from E. rupicola and E. fernandezianus were genotyped, and one to eight alleles per locus per population were detected. The expected heterozygosity ranged from 0.000 to 0.812. • CONCLUSIONS: These results indicate the utility of primers for cross-species populational studies in all endemic species of Erigeron in the Archipelago.

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En el presente trabajo se intenta demostrar la utilidad del subgalato de bismuto, sal de metal pesado con propiedades hemostáticas, para realizar la hemostasia en las amigdalectomías. Se incluyeron 213 pacientes, los cuales tenían indicación de amigdalectomía y a los que se le extirparon ambas amígdalas con la misma técnica. Se eligió un lado al azar, intentando la hemostasia sólo con subgalato de bismuto, lo que se logró en 97,2 por ciento y se comparó con los resultados obtenidos en la hemostasia del lado contralateral en que se realizó la técnica clásica de ligadura o de punto montado con catgut. De los 213 pacientes, 4 presentaron hemorragia postoperatoria, 3 precoces y una tardía. Los que sangraron sólo lo hicieron en el lado en que se usó la técnica de ligadura o punto montado con catgut. La técnica de hemostasia con subgalato de bismuto fue muy segura, ya que ningún paciente presentó hemorragia en el lado en que se utilizó; su uso no provocó complicaciones ni efectos colaterales

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Los autores presentan su experiencia de un tratamiento quirúrgico conservador del mucocele frontal en un período de cuatro años. Se describe la técnica quirúrgica de la marsupialización del seno frontal y sus ventajas estéticas. Se discute y compara con otras técnicas más radicales. Esta es una técnica simple con excelentes resultados cosméticos y un período post operatorio breve y buena tolerancia

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Los papilomas schneiderianos son tumores poco frecuentes que aparecen en las fosas nasales y cavidades paranasales. Ellos están clasificados en tres tipos histológicos: papilomas invertidos, fungiformes y de células cilíndricas. Son considerados como intermedios por su conducta agresiva. Invaden a través de extensión local y tiene una importante tendencia a recidivar. Pueden aparecer en osociación con malignidad. En su etiología se asume corrientemente un rol viral. Se confeccionó un protocolo prospectivo para el manejo del papiloma nasal en el Hospital Van Buren de Valparaíso. Trece pacientes fueron tratados en un período de 5 años: Cinco de ellos fueron operados por una rinotomía lateral y ocho por una técnica de Denker. Ambos abordajes permitieron una resección satisfactoria del tumor y tuvieron un control similar de la enfermedad. En esta serie hubo un caso de recurrencia y ninguno de malignidad. Se hace hincapié en los principios básicos del tratamiento como son: Biopsia previa a la cirugía, uso de tomografía axial computarizada (TAC), abordaje quirúrgico amplio, y la necesidad de someter cualquier tejido tomado de la fosa nasal a examen histopatológico a pesar de su aparente aspecto benigno

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