137 research outputs found
Dos adiciones al complejo Jacea–Lepteranthus: adaptaciones paralelas en las enigmáticas especies Centaurea subtilis y C. exarata
Centaurea subtilis from south east Italy and C. exarata from south west Iberia were classified in the Acrolophus- Phalolepis group and therein in section Maculosae. A molecular survey based on ITS sequence data indicates that both species should rather be placed in the Jacea-Lepteranthus group instead. This placement is consistent with the chromosome number of the two species, which is x = 11 like the rest of species of the Jacea-Lepteranthus group, and differs from the x = 9 of the other taxa included in sect. Maculosae. These results confi rm previous suggestions on the unnaturality of sect. Maculosae. Centaurea exarata and C. subtilis are quite different from the other species of Jacea-Lepteranthus in some striking morphological characters, which we hypothesize to be the result of parallel adaptation to dryer climates. The lack of competitors for pollination might be a good explanation for the partial or even total loss of showy flowers in these two species.[es] Centaurea subtilis del sureste de Italia y C. exarata del suroeste de la Península Ibérica fueron clasificadas anteriormente en el grupo Acrolophus-Phalolepis y dentro de él en la sect. Maculosae. Una revisión molecular basada en secuencias de la región ITS indica que ambas deberían clasificarse en el grupo Jacea-Lepteranthus. Este cambio es coherente con el número cromosómico de las dos especies, que tienen x = 11 como el resto de las especies del grupo Jacea-Lepteranthus y no x = 9 como las especies del grupo Acrolophus-Phalolepis. Estos resultados confirman advertencias anteriores sobre el carácter artificial de la sect. Maculosae. Centaurea exarata y C. subtilis son bastante diferentes de las otras especies de Jacea-Lepteranthus en algunos caracteres morfológicos importantes, resultado, según nuestra hipótesis, de adaptaciones a un clima más árido. La reducción o total pérdida de las flores estériles radiantes podría ser una adaptación a la falta de especies competidoras en la polinización.
[ct] Centaurea subtilis del sud-est d’Itàlia i C. exarata del sud-oest de la Península Ibèrica han estat classificades en el grup Acrolophus-Phalolepis i, dins d’aquest grup, a la secció Maculosae. Una revisió molecular basada en seqüències de la regió ITS indica que ambdues espècies haurien de classificar-se en el grup Jacea-Lepteranthus. Aquest canvi és coherent amb el nombre cromosòmic de les dues espècies, que tenen x = 11 com la resta de les espècies del grup Jacea-Lepteranthus i no x = 9 com les espècies del grup Acrolophus-Phalolepis. Aquests resultats confi rmen advertències anteriors sobre el caràcter artificial de la sect. Maculosae. Centaurea exarata i C. subtilis són bastant diferents de les altres espècies de Jacea-Lepteranthus en alguns caràcters morfològics importants, degut, segons la nostra hipòtesi, a adaptacions a un clima més àrid. La reducció o la total pèrdua de les flors estèrils radiants podria ser una adaptació a la falta d’espècies competidores en la pol·linització
Notas taxonómicas y nomenclaturales en Centaurea: propuesta de clasificación, descripción de secciones y subsecciones nuevas, y lista de especies de una sección Centaurea redefinida
In this paper, we summarize the results of our long-date research on the genus Centaurea. The first part of the paper deals with the overall classification of the genus, which we propose to divide into three subgenera: subgenus Centaurea, subgenus Cyanus and subgenus Lopholoma. The second part of this publication gives a recopilation of the species of the redefined section Centaurea, a group that includes former sections Acrolophus (sect. Centaurea s. str.), Phalolepis and Willkommia, together with taxonomical, geographical, ecological and karyological considerations. Finally, new descriptions or nomenclatural combinations are proposed to correlate nomenclature to the new classification: a new combination (sect. Acrocentron subsect. Chamaecyanus) is proposed in subgenus Lopholoma; three new sections (sects. Akamantis, Cnicus, and Hyerapolitanae) are described in subgenus Centaurea; two subsections (subsects. Phalolepis and Willkommia) in sect. Centaurea; and three subsections (subsects. Exarata, Jacea, and Subtilis) in sect. Phrygia.En este trabajo presentamos los resultados de nuestras investigaciones de larga fecha en el género Centaurea. La primera parte del trabajo trata de la clasificación del género, que proponemos dividir en tres subgéneros: subgénero Centaurea, subgénero Cyanus y subgénero Lopholoma. La segunda parte es una recopilación de las especies de la redefinida sección Centaurea, que incluye las antiguas secciones Acrolophus (sect. Centaurea s. str.), Phalolepis y Willkommia, junto con consideraciones geográficas, ecológicas y cariológicas. Por último, proponemos nuevas secciones, subsecciones y combinaciones para correlacionar nomenclatura y clasificación: proponemos una nueva (sect. Acrocentron subsect. Chamaecyanus) en el subgénero Lopholoma; se describen tres secciones nuevas (sects. Akamantis, Cnicus y Hyerapolitanae) en el subgénero Centaurea; dos subsecciones (subsects. Phalolepis and Willkommia) en la sección Centaurea; y tres subsecciones (subsects. Exarata, Jacea y Subtilis) en la sección Phrygia
Metodología multi-modal en relaciones cuantitativas estructura-actividad
Los estudios QSAR definidos en la literatura están basados en enfoques uni-modales, dejando de analizar conjuntos de datos que contienen distintas informaciones químicas. En esta investigación se propone aplicar por primera vez y analizar el comportamiento del enfoque multi-modal en el desarrollo de estudios QSAR. Para este fin se utilizó una base de compuestos con actividad hepatotóxica, a partir de la cual se construyeron cuatro modalidades considerando distintos descriptores moleculares basados en diversas teorías y enfoques. Se desarrollaron varios modelos usando los enfoques uni-modales y multi-modales utilizando algoritmos de clasificación reportados en la literatura e implementados en el lenguaje R. Los parámetros de cada uno de los algoritmos se optimizaron con el procedimiento "parametertuningwithrepeatedgrid-searchcross-validation", mientras la validación de dichos modelos se realizó mediante validación cruzada de 10 pliegues con 10 repeticiones. Estadísticamente se comprobó que el enfoque multimodal mejora el desempeño de los modelos predictivos comparado con algunos de los modelos derivados de los conjuntos de datos con modalidades individuales.Palabras Clave: enfoque multi-modal, enfoque uni-modal, estudios QSAR.</p
Generic boundaries in subtribe Saussureinae (Compositae: Cardueae): Insights from Hyb-Seq data
The subtribe Saussureinae is a highly speciose group with more than 600 species distributed in the Northern Hemisphere and is particularly species-rich at the high mountains of central and eastern Asia. Saussurea and Jurinea are the two main genera described within the subtribe. However, up to 15 satellite genera are recognized in some recent taxonomic treatments with an analytical viewpoint. For the first time, we carried out a complete sampling to clarify generic boundaries based on a well-resolved phylogeny of Saussureinae. We employed a Hyb-Seq technique that targets 1061 nuclear conserved ortholog loci designed for Compositae. After a filtering of potential paralogs, 588 loci were retained to infer phylogenetic trees under concatenation and coalescence approaches. High branch support resolution was recovered at the generic level, but a non-monophyletic pattern was detected for most of the genera as they are currently circumscribed. Accordingly, we propose a new generic delimitation based on the three main clades recovered in the backbone tree, which are also in agreement with morphological evidence: Dolomiaea, Saussurea, and Jurinea. Following this classification into three genera, 18 new combinations are proposed. This new genus delineation will be used as a basis for future evolutionary studies in the Saussureinae.Financial support from the Ministerio de Ciencia e Innovación (Project CGL2015-66703-P MINECO/FEDER, UE and Ph.D. grant to Sonia Herrando-Moraira) and the Catalan government (“Ajuts a grups consolidats” 2017-SGR1116) is also greatly acknowledged. This study has been performed under the Ph.D. program “Plant Biology and Biotechnology” of the Autonomous University of Barcelona (UAB)INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
TAXONOMIC IMPLICATIONS
NOTE ADDED IN PROOF
AUTHOR CONTRIBUTIONS
ACKNOWLEDGMENT
African Mountain Thistles: Three New Genera in the Carduus-Cirsium Group
The floras on the highest mountains in tropical eastern Africa are among the most unique floras in the world. Despite the exceptionally high concentration of endemic species, these floras remain understudied from an evolutionary point of view. In this study, we focus on the Carduus-Cirsium group (subtribe Carduinae) to unravel the evolutionary relationships of the species endemic to the tropical Afromontane and Afroalpine floras, aiming to improve the systematics of the group. We applied the Hyb-Seq approach using the Compositae1061 probe set on 190 samples (159 species), encompassing representatives of all genera of Carduinae. We used two recently developed pipelines that enabled the processing of raw sequence reads, identification of paralogous sequences and segregation into orthologous alignments. After the implementation of a missing data filter, we retained sequences from 986 nuclear loci and 177 plastid regions. Phylogenomic analyses were conducted using both concatenated and summary-coalescence methods. The resulting phylogenies were highly resolved and revealed three distinct evolutionary lineages consisting of the African species traditionally referred to as Carduus and Cirsium. Consequently, we propose the three new genera Afrocarduus, Afrocirsium and Nuriaea; the latter did notably not belong to the Carduus-Cirsium group. We detected some incongruences between the phylogenies based on concatenation vs. coalescence and on nuclear vs. plastid datasets, likely attributable to incomplete lineage sorting and/or hybridization
Impact of the climatic changes in the Pliocene-Pleistocene transition on Irano-Turanian species. The radiation of genus Jurinea (Compositae)
Altres ajuts: acords transformatius de la UABThe Irano-Turanian region is one of the world's richest floristic regions and the centre of diversity for numerous xerophytic plant lineages. However, we still have limited knowledge on the timing of evolution and biogeographic history of its flora, and potential drivers of diversification remain underexplored. To fill this knowledge gap, we focus on the Eurasian genus Jurinea (ca. 200 species), one of the largest plant radiations that diversified in the region. We applied a macroevolutionary integrative approach to explicitly test diversification hypotheses and investigate the relative roles of geography vs. ecology and niche conservatism vs. niche lability in speciation processes. To do so, we gathered a sample comprising 77% of total genus richness and obtained data about (1) its phylogenetic history, recovering 502 nuclear loci sequences; (2) growth forms; (3) ecological niche, compiling data of 21 variables for more than 2500 occurrences; and (4) paleoclimatic conditions, to estimate climatic stability. Our results revealed that climate was a key factor in the evolutionary dynamics of Jurinea. The main diversification and biogeographic events that occurred during past climate changes, which led to colder and drier conditions, are the following: (1) the origin of the genus (10.7 Ma); (2) long-distance dispersals from the Iranian Plateau to adjacent regions (∼7-4 Ma); and (3) the diversification shift during Pliocene-Pleistocene Transition (ca. 3 Ma), when net diversification rate almost doubled. Our results supported the pre-adaptation hypothesis, i.e., the evolutionary success of Jurinea was linked to the retention of the ancestral niche adapted to aridity. Interestingly, the paleoclimatic analyses revealed that in the Iranian Plateau long-term climatic stability favoured old-lineage persistence, resulting in current high species richness of semi-arid and cold adapted clades; whereas moderate climate oscillations stimulated allopatric diversification in the lineages distributed in the Circumboreal region. In contrast, growth form lability and high niche disparity among closely related species in the Central Asian clade suggest adaptive radiation to mountain habitats. In sum, the radiation of Jurinea is the result of both adaptive and non-adaptive processes influenced by climatic, orogenic and ecological factors
Island-like mountain radiations in Asia: The case study of the genera Saussurea and Jurinea
Trabajo presentado en el XIX International Botanical Congress (IBC 2017), celebrado en Shenzhen (China) del 23 al 29 de julio de 2017Evolutionary radiations represent events in which many species or lineages evolved from a common ancestor in a short period of time. Many plant radiations have been triggered by island-like ecological opportunities following mountain uplift; the mountain ranges with the steepest and widest environmental gradients, such
as the Andes, are home of exceptional regional species pools (and also exceptional endemism rates), mainly derived from evolutionary radiations. The Himalayan-Qinghai-Tibetan Plateau (HQTP) and the adjacent Hengduan Mountains (HM) are considered one of the main biodiversity hotspots of the world thanks to its richness in species and endemics. Both regions show extreme altitudinal ranges compressed in short distances as a consequence of the collision of the Indian and Eurasian plates, and thus constitute
ideal evolutionary scenarios to study diversification processes in mountain regions. We have identified two possible cases of alpine radiations in the Saussurea-Jurinea complex (Compositae-Cardueae),
involving some 550 species in total. Saussurea shows an amazing number of species (more than 300) in the HQTP and Hengduan mountains, although a considerable number of species are also found on the west side of the mountains of Middle Asia (Tian Shan and Pamir-Alay). Jurinea, in contrast, has the highest
number of species (150 sp.) in the Tian Shan and Pamir-Alay. Our general objectives are the following: a) To carry out an extensive sampling of Saussurea and Jurinea, especially centred in the two main radiation areas in the HQTP and Tian Shan mountains; b) To generate well-resolved phylogenies of both genera using a
multi-loci approach through next-generation-sequencing (NGS) analyzed by Bayesian inference and parsimony, and explore coalescent-based species tree estimation with our NGS data set; c) On the basis of the new phylogenies, conduct phylogenetic comparative analyses and multi-model biogeographical inference
to address the following questions: Do the alpine species of both genera in Asian mountains constitute clades with clearly higher rates of diversification than their lowland relatives? How many independent radiations took place in the complex? If several, did they occur at the same period, and are they comparable in terms of
speciation rates? Which factors (intrinsic or extrinsic) shape species radiations, i.e., do the radiations follow a geographical model, an adaptive model, or a mixed model? Our results will be a major contribution to the study of alpine radiations especially in the HQTP, and will open a methodological pathway for the analysis
of very large radiations in other genera.Peer reviewe
L'Autocontrol als establiments alimentaris: guia per a l'aplicació de l'autocontrol basat en el Sistema d'Anàlisi de Perills i Punts de Control Crític
Autocontrol; APPCC; Establiments alimentarisAutocontrol; APPCC; Establecimientos alimentariosSelf-control; HACCP; Food EstablishmentsGuía para el diseño y la aplicación por parte de las empresas alimentarias de autocontroles basados en el Sistema de Análisis de Peligros y Puntos de Control Crítico (APPCC) dirigido a los establecimientos alimentarios, su extensión a los sectores que se encuentran al principio de la cadena alimentaria y la formación de todos los profesionales que actúan a lo largo del proceso de obtención de alimentos. Documento elaborado por expertos en el control oficial y en la verificación y la supervisión de sistemas de autocontrol del Departamento de Salud y de la Agencia de Salud Pública de Barcelona. El objetivo es la prevención de riesgos sanitarios asociados el consumo de alimentos y facilitará a los operadores de los establecimientos alimentarios la aplicación real y efectiva de autocontroles basados en el Sistema de APPCC para producir alimentos seguros.Guia per al dissey i l'aplicació per part de les empreses alimentàries d’autocontrols basats en el Sistema d’Anàlisi de Perills i Punts de Control Crític (APPCC) dirigit als establiments alimentaris, la seva extensió als sectors que es troben al principi de la cadena alimentària i la formació de tots els professionals que actuen al llarg del procés d’obtenció d’aliments. Document elaborat per experts en el control oficial i en la verificació i la supervisió de sistemes d’autocontrol del Departament de Salut i de l’Agència de Salut Pública de Barcelona. L'objectiu és la prevenció de riscos sanitaris associats al consum d’aliments i facilitarà als operadors dels establiments alimentaris l’aplicació real i efectiva d’autocontrols basats en el Sistema d’APPCC, per tal de produir aliments segurs
Prognostic factors associated with mortality risk and disease progression in 639 critically ill patients with COVID-19 in Europe: Initial report of the international RISC-19-ICU prospective observational cohort
Distributed and multicore QuBiLS‐MIDAS software v2.0: Computing chiral, fuzzy, weighted and truncated geometrical molecular descriptors based on tensor algebra
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