Are long-distance dispersal syndromes associated with the conservation status of plant species? The Canary Islands as a case study

Dispersal is the process that allows organisms to reach new suitable territories and expand their area of occupancy. In plants, long-distance dispersal (LDD) of diaspores is related to the presence of morphological structures (dispersal syndromes) that favor mobility by wind (anemochorous), sea currents (thalasochorous) and animals (epizoochorous and endozoochorous). The relationship between these LDD structures and the distribution of plant species is related to characteristics of different archipelagoes. Previous studies in several archipelagoes found that the Canary Islands showed the strongest positive relationship between dispersal syndromes and species distributions. It has been long hypothesized that species without specialized structures for dispersal have more difficulties in expanding their areas of occupancy and consequently these species are more threatened because of limited distribution. Nevertheless, the effect of the dispersal ability of plant species on the degree of threat has never been tested in oceanic archipelagoes. In this study, we selected the 262 lowland endemic plant species of the Canary Islands and evaluated the relationship between the presence/absence of the four LDD syndromes and their threat status. A considerable number of threatened (154 spp.) and non-threatened (108 spp.) species were observed, of which 93 had LDD syndromes and 169 did not. Our analyses failed to find statistically significant differences between the number of threatened species with and without LDD syndromes and their IUCN threatened status. In sum, this study shows a poor contribution of dispersal abilities in the degree of threat of endemic plant species in the Canary Islands

PAICE: A new R package to estimate the number of inter-island colonizations considering haplotype data and sample size

Aim: Colonization is a central topic in ecology and one of the cornerstones of island biogeography. Although the evolutionary history of island species is widely studied, the quantification of colonization is particularly challenging because the same area may be colonized multiple times by the same species, whereas initially successful colonization events may eventually be followed by extinction. Nevertheless, an estimation of the actual number of within-archipelago colonization events can be achieved when using adequate sample size and genetic data, which are essential parameters in the inference of colonization success of any species. Location: Canary Islands, Azores and Galápagos Islands. Taxon: Buteo galapagoensis, Croton scouleri, Setophaga petechia aureola and Xylocopa darwini (Galápagos); Canarina canariensis, Cistus monspeliensis, Juniperus cedrus and Olea europaea subsp. guanchica (Canary Islands); and Juniperus brevifolia and Picconia azorica (Azores). Methods: The new R package PAICE uses haplotype (from organelle DNA) sharing and haplotype relationships, and controls for sampling effort to estimate the number of within-archipelago colonization events in island-like systems. PAICE applies a sampling-effort correction based on rarefaction curves of field sampling (number of individuals or populations) and genetic sampling (number of DNA variable positions). The number of colonization events for the 10 insular species were estimated with PAICE and results compared with previous methods. Results: PAICE estimates a number of inter-island colonization events up to an order of magnitude greater than previous methods. Furthermore, PAICE can quantify the colonization events of any study species, in multiple biogeographic contexts and considering sampling size, thus providing a standardized estimate of colonization success. Main conclusions: The new package PAICE provides an estimation of the number of inter-island colonization events (regardless of dispersal routes or rates) based on haplotype data across islands. This new tool will allow gaining new insights on the intensity of long-distance-dispersal events, their drivers and consequences for the assembly of insular faunas and floras

Detectability and accuracy of computational measurements of in-silico and physical representations of enlarged perivascular spaces from magnetic resonance images

BACKGROUND: Magnetic Resonance Imaging (MRI) visible perivascular spaces (PVS) have been associated with age, decline in cognitive abilities, interrupted sleep, and markers of small vessel disease. But the limits of validity of their quantification have not been established. NEW METHOD: We use a purpose-built digital reference object to construct an in-silico phantom for addressing this need, and validate it using a physical phantom. We use cylinders of different sizes as models for PVS. We also evaluate the influence of 'PVS' orientation, and different sets of parameters of the two vesselness filters that have been used for enhancing tubular structures, namely Frangi and RORPO filters, in the measurements' accuracy. RESULTS: PVS measurements in MRI are only a proxy of their true dimensions, as the boundaries of their representation are consistently overestimated. The success in the use of the Frangi filter relies on a careful tuning of several parameters. Alpha= 0.5, beta= 0.5 and c= 500 yielded the best results. RORPO does not have these requirements and allows detecting smaller cylinders in their entirety more consistently in the absence of noise and confounding artefacts. The Frangi filter seems to be best suited for voxel sizes equal or larger than 0.4 mm-isotropic and cylinders larger than 1 mm diameter and 2 mm length. 'PVS' orientation did not affect measurements in data with isotropic voxels. COMPARISON WITH EXISTENT METHODS: Does not apply. CONCLUSIONS: The in-silico and physical phantoms presented are useful for establishing the validity of quantification methods of tubular small structures

Historia geológica y reconstrucción paleobiológica de los depósitos paleontológicos de la playa de El Confital (Gran Canaria, islas Canarias)

XXXIV Jornadas de Paleontología y IV Congreso Ibérico de Paleontología (Vila Real, Portugal. Sep 2018) p. 491-499El archipiélago canario está situado cerca de la costa NO de África y es de naturaleza volcánica. Fuerteventura y Lanzarote son las islas más antiguas del archipiélago (23 y 15 Ma aproximadamente) seguidas por Gran Canaria (14 Ma), siendo en estas tres islas solamente donde vamos a encontrar depósitos fosilíferos pertenecientes a las series Mioceno y Plioceno (Meco et al., 2015). El episodio MIS5e (Eemiense), por el contrario, podemos encontrarlo en todas las islas (Meco et al., 2002; Zazo et al., 2003; Martín-González et al., 2016). Este trabajo se centra en el estudio de los depósitos fosilíferos asociados a ambos periodos que aparecen en la playa de El Confital, en la isla de Gran Canaria Los afloramientos se encuentran al suroeste de La Isleta, un islote eminentemente volcánico situado en el extremo NE de Las Palmas de Gran Canaria unido al edificio insular principal por un tómbolo de arena, el istmo de Guanarteme. Se trata de una plataforma litoral activa modelada sobre piroclastos de origen hidromagmático (Hansen, 2008), que ha sido alterada antrópicamente en tiempos recientes. Las Palmas de Gran Canaria constituye uno de los escasos ejemplos en los que se pueden observar yacimientos paleontológicos de diferentes edades. En la parte alta de la ciudad se encuentra la Formación Detrítica de Las Palmas, de edad Mio-Plioceno, que contiene una importante asociación fosilífera estudiada por diferentes autores (Rothpletz & Simonelli, 1890; Meco et al., 2007; Betancort, 2012; Martín-González et al., 2018); mientras que en la zona baja se encuentran los afloramientos pertenecientes al episodio transgresivo marino MIS5e (Meco et al., 2002). En la playa de El Confital podemos encontrar, en ambos extremos, los yacimientos del Eemiense, al sur, cuyo estudio paleontológico y estratigráfico preliminar fue realizado por Cabrera (1987) y del Mioceno, al noroeste, donde Meco et al. (2015) citan por primera vez la existencia del nivel con Ostrea offretti Linnaeus. En este trabajo realizamos un análisis volcano-estratigráfico y paleontológico integral de la playa de El Confital con el fin de reconstruir la evolución temporal de la fauna fosilizada en esta zona.Museo de Ciencias Naturales (MCN). OAMCÁrea de Paleontología, Facultad de Biología, Universidad de La LagunaDpto. de Geologia, Faculdade de Ciências, Universidade de LisboaCIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Pólo dos AçoresInstituto Dom Luiz, Faculdade de Ciências da Universidade de LisboaUnidad Territorial de Canarias, Instituto Geológico y Minero de España (IGME)IOCAG. Instituto de Oceanografía y Cambio Global. Universidad de Las Palmas de Gran CanariaTELLUS. Arqueología y Prehistoria en el Sur de Iberia. HUM-949Department of Geosciences, Williams CollegeDpto. de Geografía. Universidad de La LagunaÁrea de Patrimonio Geológico y Minero, Instituto Geológico y Minero de España (IGME).Área de Geología. Universidad Rey Juan Carlo

Sexual Selection Halts the Relaxation of Protamine 2 among Rodents

Sexual selection has been proposed as the driving force promoting the rapid evolutionary changes observed in some reproductive genes including protamines. We test this hypothesis in a group of rodents which show marked differences in the intensity of sexual selection. Levels of sperm competition were not associated with the evolutionary rates of protamine 1 but, contrary to expectations, were negatively related to the evolutionary rate of cleaved- and mature-protamine 2. Since both domains were found to be under relaxation, our findings reveal an unforeseen role of sexual selection: to halt the degree of degeneration that proteins within families may experience due to functional redundancy. The degree of relaxation of protamine 2 in this group of rodents is such that in some species it has become dysfunctional and it is not expressed in mature spermatozoa. In contrast, protamine 1 is functionally conserved but shows directed positive selection on specific sites which are functionally relevant such as DNA-anchoring domains and phosphorylation sites. We conclude that in rodents protamine 2 is under relaxation and that sexual selection removes deleterious mutations among species with high levels of sperm competition to maintain the protein functional and the spermatozoa competitive

Implementación en la UCM del Grado en Estudios Europeos / Bachelor in European Studies en el marco de la alianza europea de universidades UNA EUROPA

El presente proyecto de innovación ha tenido por objetivo la implementación en la Universidad Complutense de Madrid del Nuevo Grado en Estudios Europeos / Bachelor of European Studies (BAES) creado en el marco de la nueva alianza europea de universidades UNA EUROPA integrada por la Universidad Complutense de Madrid, la Universidad de la Sorbona (París – I), Universidad Libre de Berlín, Universidad de Bolonia, Universidad Jaguelónica de Cracovia, Universidad de Helsinki, Universidad Católica de Lovaina, y Universidad de Edimburgo

Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe