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The southern coastline of South America is a remarkable area to evaluate how Quaternary glacial processes impacted the demography of the near-shore marine biota. Here we present new phylogeographic analyses in the pulmonate Siphonaria lessonii across its distribution, from northern Chile in the Pacific to Uruguay in the Atlantic. Contrary to our expectations, populations from the southwestern Atlantic, an area that was less impacted by ice during glacial maxima, showed low genetic diversity and evidence of recent expansion, similar to the patterns recorded in this study across heavily ice-impacted areas in the Pacific Magellan margin. We propose that Atlantic and Pacific shallow marine hard-substrate benthic species were both affected during the Quaternary in South America, but by different processes. At higher latitudes of the southeast Pacific, ice-scouring drastically affected S. lessonii populations compared to non-glaciated areas along the Chile-Peru province where the species was resilient. In the southwest Atlantic, S. lessonii populations would have been dramatically impacted by the reduction of near-shore rocky habitat availability as a consequence of glacio-eustatic movements. The increase of gravelly and rocky shore substrates in the southwest Atlantic supports a hypothesis of glacial refugia from where the species recolonized lower latitudes across the Atlantic and Pacific margins. Our results suggest that current patterns of genetic diversity and structure in near-shore marine benthic species do not solely depend on the impact of Quaternary glacial ice expansions but also on the availability of suitable habitats and life-history traits, including developmental mode, bathymetry and the likelihood of dispersal by rafting.

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Single and double-slit experiments are performed with two microwave billiards with the shapes of a rectangle and a quarter stadium, respectively. The classical dynamics of the former is regular, whereas that of the latter is chaotic. Microwaves can leave the billiards via slits in the boundary, forming interference patterns on a screen. The aim is to determine the effect of the billiard dynamics on their structure. For this the development of a method for the construction of a directed wave packet by means of an array of multiple antennas was crucial. The interference patterns show a sensitive dependence not only on the billiard dynamics but also on the initial position and direction of the wave packet.

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Resonance spectra of two-dimensional dielectric microwave resonators of circular and square shapes have been measured. The deduced length spectra of periodic orbits were analyzed and a trace formula for dielectric resonators recently proposed by Bogomolny [Phys. Rev. E 78, 056202 (2008)] was tested. The observed deviations between the experimental length spectra and the predictions of the trace formula are attributed to a large number of missing resonances in the measured spectra. We show that by taking into account the systematics of observed and missing resonances the experimental length spectra are fully understood. In particular, a connection between the most long-lived resonances and certain periodic orbits is established experimentally.

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Biological invasions are excellent opportunities to study the evolutionary forces leading to the adaptation of a species to a new habitat. Knowledge of the introduction history of colonizing species helps tracking colonizing routes and assists in defining management strategies for invasive species. The Palearctic species Drosophila subobscura is a good model organism for tracking colonizations since it was detected in Chile and western North America three decades ago and later on in the Atlantic coast of Argentina. To unravel the origin of the Argentinean colonizers two populations have been analysed with several genetic markers. Chromosomal arrangements and microsatellite alleles found in Argentina are almost similar to those observed in Chile and USA. The lethal allelism test demonstrates that the lethal gene associated with the O(5) inversions in Argentina is identical to that found in Chile and USA, strongly supporting the hypothesis that all the American colonizing populations originated from the same colonization event. A secondary bottleneck is detected in the Argentinean populations and the genetic markers suggest that these populations originated from the invasion of 80-150 founding individuals from Chile.

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The genetic and ecological basis of viability and developmental time differences between Drosophila buzzatii and D. koepferae were analysed using the isofemale line technique. Several isofemale lines were sampled from pairs of allopatric/sympatric populations of each species. Flies were reared in media prepared with decaying tissues of two of the main natural cactus hosts of each species. This experimental design enabled us to evaluate the relative contribution of phenotypic plasticity, genetic variation and genotype by environment interaction (G x E) to total phenotypic variation for two fitness traits, viability and developmental time. Our results revealed significant G x E in both traits, suggesting that the maintenance of genetic variation can be explained, at least in part, by diversifying selection in different patches of a heterogeneous environment in both species. However, the relative importance of the factors involved in the G x E varied between traits and populations within species. For viability, the G x E can be mainly attributed to changes in the rank order of lines across cacti. However, the pattern was different for developmental time. In D. buzzatii the G x E can be mainly accounted for by changes in among line variance across cacti, whereas changes in the rank order of lines across cacti was the main component in D. koepferae. These dissimilar patterns of variation between traits and species suggest that the evolutionary forces shaping genetic variation for developmental time and viability vary between populations within species and between species.

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Latitudinal clinal variation in wing size and shape has evolved in North American populations of Drosophila subobscura within about 20 years since colonization. While the size cline is consistent to that found in original European populations (and globally in other Drosophila species), different parts of the wing have evolved on the two continents. This clearly suggests that 'chance and necessity' are simultaneously playing their roles in the process of adaptation. We report here rapid and consistent thermal evolution of wing shape (but not size) that apparently is at odds with that suggestion. Three replicated populations of D. subobscura derived from an outbred stock at Puerto Montt (Chile) were kept at each of three temperatures (13, 18 and 22 degrees C) for 1 year and have diverged for 27 generations at most. We used the methods of geometric morphometrics to study wing shape variation in both females and males from the thermal stocks, and rates of genetic divergence for wing shape were found to be as fast or even faster than those previously estimated for wing size on a continental scale. These shape changes did not follow a neat linear trend with temperature, and are associated with localized shifts of particular landmarks with some differences between sexes. Wing shape variables were found to differ in response to male genetic constitution for polymorphic chromosomal inversions, which strongly suggests that changes in gene arrangement frequencies as a response to temperature underlie the correlated changes in wing shape because of gene-inversion linkage disequilibria. In fact, we also suggest that the shape cline in North America likely predated the size cline and is consistent with the quite different evolutionary rates between inversion and size clines. These findings cast strong doubts on the supposed 'unpredictability' of the geographical cline for wing traits in D. subobscura North American colonizing populations.

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A prospective, multicenter pharmacovigilance study was carried out to evaluate the safety of a new 7-dose treatment schedule of subcutaneous immunotherapy as opposed to the conventional 13 doses normally recommended. The study was carried out in 14 centers and included 261 patients (children and adults) with respiratory allergic disease due to sensitization to mites (Dermatophagoides pteronyssinus and/or farinae). A total of 2290 doses were administered under the direct supervision of the participating specialists. One hundred and ten reactions in 63 patients (24.1%) were recorded, representing 4.8% of the total doses administered. Most of the reactions (98) were local. Only 12 were systemic (0.5% of the administered doses) and occurred in 10 patients (3.8% of the sample). Ten reactions reverted quickly with rescue medication. The maintenance dose had to be lowered in one patient and another patient was withdrawn from the study after suffering two asthmatic crises after two consecutive doses. In view of the results obtained, we can conclude that the new schedule shows an acceptable tolerance profile and does not present a greater risk of reactions than the conventional scheme of 13 doses using an identical extract. Moreover, the new schedule represents substantial savings in the number of doses and visits required to reach the maintenance dose.

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I.UNA MIRADA CRITICA A NUESTRO MUNDO 1.La población mundial y sus proyecciones 2.Países Ricos - Países pobres 3.El poder de las multinacionales 4.Indices de pobreza en el mundo 5.Indices de desarrollo humano 6.La salud y otros graves problemas sociales 7.La economía mundial y sus grandes desafíos 8.Graves problemas emergentes en nuestra sociedad 9.Problemas de la infancia 10.Problemas de género 11.La deuda externa del tercer mundo 12.Compendio de estadísticas mundiales 13.La corrupcion en el mundo 14.Armamentismo 15.Ecología 16.Disminuye la ayuda de los países ricos 17.Entre la modernidad y la post modernidad 18.El neoliberalismo globalizador 19.El fin del triunfalismo neo-liberal 20.Los procesos de integración 21.Organismos internacionales de desarrollo II.AMERICA LATINA: ESPERANZAS, FRUSTRACIONES Y DESAFIOS 1.Poblacion de America Latina 2.Pobreza y riquezas en AL 3.Dimensiones de la pobreza en AL 4.La educación en AL 5.Economía: crecimiento y recesión 6.La deuda externa de AL 7.El deterioro del medio ambiente 8.La droga y el narcotráfico 9.La integración regional III.REALIDAD DE BOLIVIA, DATOS Y ANALISIS 1.Perfil poblacional 2.La pobreza en Bolivia 3.Realidad económica 4.La crisis económica y sus factores 5.El gas: el gran reto de Bolivia 6.Exportaciones - importaciones 7.El área rural y sus problemas 8.La economía informal 9.Sueldos y salarios 10.La deuda externa: sus dimensiones y exigencias morales 11.Empleo y sub - empleo 12.Hambre y desnutrición 13.Mortalidad en Bolivia 14.Salud y enfermedad 15.El SIDA se expande en Bolivia 16.Narcotráfico, drogadicción y alcoholismo 17.La educación y sus desafíos 18.Vivienda, servicios: agua, luz 19.Indices de desarrollo humano 20.Discriminación contra la mujer 21.Problemas de la niñez y ancianidad 22.La corrupcion 23.La política y los políticos 24.Los medios de comunicación y sus impacto en la sociedad 15.Minería 16.Ecología y medio ambiente 17.La nuevas leyes y sus interrogantes IV.DISCERNIMIENTO CRITICO Y ORIENTACIONES PRACTICAS(C)

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A prospective, multicenter pharmacovigilance study was carried out to evaluate the safety of a new 7-dose treatment schedule of subcutaneous immunotherapy as opposed to the conventional 13 doses normally recommended. The study was carried out in 14 centers and included 261 patients (children and adults) with respiratory allergic disease due to sensitization to mites (Dermatophagoides pteronyssinus and/or farinae). A total of 2290 doses were administered under the direct supervision of the participating specialists. One hundred and ten reactions in 63 patients (24.1 %) were recorded, representing 4.8 % of the total doses administered. Most of the reactions (98) were local. Only 12 were systemic (0.5 % of the administered doses) and occurred in 10 patients (3.8 % of the sample). Ten reactions reverted quickly with rescue medication. The maintenance dose had to be lowered in one patient and another patient was withdrawn from the study after suffering two asthmatic crises after two consecutive doses. In view of the results obtained, we can conclude that the new schedule shows an acceptable tolerance profile and does not present a greater risk of reactions than the conventional scheme of 13 doses using an identical extract. Moreover, the new schedule represents substantial savings in the number of doses and visits required to reach the maintenance dose (AU)

Se ha llevado a cabo un estudio prospectivo y multicéntrico de farmacovigilancia, con el objetivo de valorar la seguridad de una nueva pauta en inmunoterapia subcutánea de 7 dosis, frente a las 13 de la pauta convencional habitualmente recomendada. El estudio se realizó en 14 centros, incluyéndose 261 pacientes (niños y adultos) con enfermedad alérgica respiratoria por sensibilización a ácaros (Dermatophagoides pteronyssinus y/o farinae). Se administraron un total de 2.290 dosis, todas ellas bajo la supervisión directa de los especialistas participantes. Se registraron 110 reacciones en 63 pacientes (24,1 por ciento), lo que supone un porcentaje sobre el total de dosis administradas del 4,8 por ciento. La mayoría de reacciones (98) fueron locales. Tan sólo 12 fueron sistémicas (0,5 por ciento sobre las dosis administradas) las cuales ocurrieron en 10 pacientes (3,8 por ciento de la muestra). En 10 casos revertieron rápidamente con medicación de alivio, en 1 caso fue necesario bajar la dosis de mantenimiento, y en 1 paciente se decidió retirarle del estudio por padecer 2 crisis asmáticas en dos dosis consecutivas. A la vista de los resultados obtenidos, podemos concluir que la nueva pauta ensayada presenta un adecuado perfil de tolerancia, no existiendo mayor riesgo de reacciones al compararlo con el perfil de la pauta convencional de 13 dosis utilizando idéntico extracto. Además, la nueva pauta supone un notable ahorro en el número de dosis y visitas necesarias para alcanzar la dosis de mantenimiento (AU)

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Una mirada critica a nuestro mundo, America Latina, esperanzas, frustraciones y desafios, realidad de Bolivia, datos y analisis, discernimiento critico y orientaciones practicas, la 16 edicion de 2007

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The cactophilic Drosophila buzzatii provides an excellent model for the study of reaction norms across discrete environments because it breeds on rotting tissues (rots) of very different cactus species. Here we test the possible effects of second chromosome inversions on body size and shape (wing loading) across suitable natural breeding substrates. Using homokaryotypic stocks derived from several lines homozygous for four naturally occurring chromosomal inversions, we show that arrangements significantly affect size-related traits and wing loading. In addition, karyotypes show differing effects, across natural breeding resources, for wing loading. The 2st and 2jz(3) arrangements decrease and the 2j arrangement increases wing loading. For thorax length and wing loading, karyotypic correlations across host plants are slightly lower in females than in males. These results support the hypothesis that these traits have a genetic basis associated with the inversion polymorphism.

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Inversion polymorphisms often have been associated with fitness variation. Cactophilic Drosophila buzzatii has been used widely for the study of the maintenance of chromosomal variation. The purpose of this paper is to address the relative importance of variable selection regimes associated with the use of three different host cacti and antagonistic pleiotropy in the maintenance of chromosomal variation. Using homokaryotypic stocks derived from several lines homozygous for four second-chromosome arrangements, we show that inversions significantly affect first-instar larva to adult viability (VT), developmental time (DT) and adult thorax length (TL). We also show that the effects of inversions on DT and VT are dependent on the cactus rearing media. The effects of polymorphic gene arrangements on life-history traits suggest the existence of trade-offs between early and late fitness components. The dosage of arrangement 2st, the ancestral gene order, was negatively correlated with DT and TL, whereas flies carrying the derived arrangements 2j and 2jq7 had longer DTs and larger TLs. Arrangements 2st and 2jq7 increased viability, at least in one of the cactus media tested. Our results suggest that environmental heterogeneity, as represented by the use of different cactus hosts and the trade-off between DT and TL, may be involved in the maintenance of the polymorphism. In addition, our data suggest that the chromosomal phylogeny may be decoupled from the evolution of the genes affecting life-history traits linked to the inversion system.

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The inversion polymorphism of the cactophilic fly Drosophila buzzatii was studied in two natural populations. We assessed the temporal changes and microspatial population structure. We observed a significant increase in the frequency of arrangement 2J at the expense of 2ST in both populations. These gene arrangements appear to affect the life-history of flies differently. Environmental heterogeneity explains the karyotype coexistence in nature. The analysis of population structure showed that differentiation of inversion frequencies among individual breeding sites, the rotting clacodes of Opuntia vulgaris, was highly significant. The karyotypic frequencies did not depart significantly from Hardy-Weinberg expectations, neither in individual rots nor in the total population. These results suggest that the observed population structure can be easily accounted by random genetic drift.

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