Microsatellites reveal substantial among-population genetic differentiation and strong inbreeding in the relict fern Dryopteris aemula

Background and Aims A previous study detected no allozyme diversity in Iberian populations of the buckler-fern Dryopteris aemula. The use of a more sensitive marker, such as microsatellites, was thus needed to reveal the genetic diversity, breeding system and spatial genetic structure of this species in natural populations. Methods Eight microsatellite loci for D. aemula were developed and their cross-amplification with other ferns was tested. Five polymorphic loci were used to characterize the amount and distribution of genetic diversity of D. aemula in three populations from the Iberian Peninsula and one population from the Azores. Key Results Most microsatellite markers developed were transferable to taxa close to D. aemula. Overall genetic variation was low (HT = 0·447), but was higher in the Azorean population than in the Iberian populations of this species. Among-population genetic differentiation was high (FST = 0·520). All loci strongly departed from Hardy-Weinberg equilibrium. In the population where genetic structure was studied, no spatial autocorrelation was found in any distance class. Conclusions The higher genetic diversity observed in the Azorean population studied suggested a possible refugium in this region from which mainland Europe has been recolonized after the Pleistocene glaciations. High among-population genetic differentiation indicated restricted gene flow (i.e. lack of spore exchange) across the highly fragmented area occupied by D. aemula. The deviations from Hardy-Weinberg equilibrium reflected strong inbreeding in D. aemula, a trait rarely observed in homosporous ferns. The absence of spatial genetic structure indicated effective spore dispersal over short distances. Additionally, the cross-amplification of some D. aemula microsatellites makes them suitable for use in other Dryopteris tax

Depresión en parados. El efecto de la resiliencia y el apoyo social.

Introducción: La actualidad nos pone ante una situación de crisis en la que, durante los últimos años, se ha generado una gran cantidad de parados, concretamente 5.457.700 a finales de 2014. Entre los efectos de esta situación, a nivel psicológico, se encuentra el padecimiento de depresión (Libby y cols., 2010). Los estudios muestran que hay una relación positiva entre estar parado y tener depresión (Booker y Sacker, 2012). Así mismo, diversos estudios (Kroll, Lampert y Devitt, 2011), muestran que los desempleados tienen más problemas de salud que los empleados, y que el apoyo social facilita afrontar el desempleo. El objetivo del presente trabajo es conocer si existe diferencia en cuanto a la depresión que padecen los sujetos que se encuentran en paro y los que no lo están; asimismo nos interesa conocer el efecto que puede tener en ambas muestras el apoyo social percibido y la resiliencia. Método: Para dar respuesta al objetivo se recogió muestra de 98 sujetos que se encontraban trabajando y en paro y, de modo voluntario y anónimo, rellenaron los cuestionarios: BDI de Beck para depresión, DUKE UNK para apoyo social y la escala de resiliencia de Wagnild y Young. Resultados: Los resultados muestran altos niveles en depresión, especialmente entre la muestra de parados; no obstante, apuntan a que el efecto del apoyo social matiza y mejora los niveles de depresión entre los parados y que los parados con baja resiliencia son proclives a padecerla.Introduction: Nowadays in a situation of crisis, during the last years, it has generated a lot of unemployed people, particularly 5.457.700 at the end of 2014. Among the effects of this situation, in the psychological field, it is found suffering from depression (Libby et al., 2010). Studies show that there is a positive relationship between being unemployed and being depressed (Booker & Sacker, 2012). In that way, several studies (Kroll, Lampery and Devitt, 2011) show that the unemployed people have more health problems than the employed ones, and that social support facilitates facing up to unemployment. The aim of this study is to determine whether there is difference in depression suffered by subjects who are unemployed and those who are not; also we want to know the effect it can have on both samples perceived social support and resilience. Method: To be able to give an answer to the main goal, 98 samples of subjects who were working or unemployed were gathered together and voluntarily and anonymously, completed questionnaires: BDI Beck Depression, DUKE UNK for social support and resilience’s scale of Wagnild and Young. Results: The results show high levels of depression, especially among the sample of unemployed people; nevertheless, they suggest that the effect of social support clarifies and improves levels of depression among the unemployed and also shows that unemployed people with low resilience are prone to suffer from it

Influence of water availability on gender determination of gametophytes in a diploid –polyploid complex of a xerophytic fern genus

Environmental sex determination (ESD) is present in several animal and plant lineages. Diverse factors such as temperature, light or water availability have been described as sex determinants in these organisms. Among plants, ferns frequently display ESD. This work compares the effect of different levels of water availability in two diploid species of the xerophytic fern genus Cheilanthes and in their derived tetraploid, and if they are sensitive to antheridiogen (i.e. maleness-inducing pheromone). Different watering regimes were applied to isolated gametophyte cultures of the three study species. Gametophyte survival, size, gender and sporophyte production were assessed after 13, 18 and 23 weeks of culture. Cultures combining spores and adult gametophytes were established to test the effect of antheridiogen. Isolated gametophytes had an asexual to female to bisexual sequence that did not depend upon the degree of soil moisture. Both gender expression and growth reduction in response to water scarcity of the allotetraploid were more similar to those of one of the diploid parents. In all watering regimes, survival was higher in the allotetraploid, suggesting hybrid vigour, whereas automixis rate was similar in the three species and reached 50 % at high moisture. This breeding system can ensure reproduction in the absence of males. In the three species, female gametophytes produced antheridiogens that enhanced maleness. This promotes a mixed mating system that could be favourable for ferns growing in xeric habitats

Postural syndromes and postural reeducationin the temporomandibular disorders

[Resumen] Este artículo tiene como objetivo realizar una revisión bibliográfica sobre qué aspectos posturales pueden estar en relación con los trastornos temporomandibulares. Describir el Síndrome de Postura de Cabeza Adelantada, y el Síndrome Cruzado Proximal; y los distintos métodos de reeducación postural para su tratamiento.[Abstract] The aim of this article is to achieve a bibliographical revision about the different postures that could be relatinated to temporo-mandibular disorders. Moreover, it describes Forward Head Sindrome, the Proximal Crossed Sindrome and several postural reeducation techniques needed for their treatment

Island plants with newly discovered reproductive traits have higher capacity for uniparental reproduction, supporting Baker’s law

Uniparental reproduction is advantageous when lack of mates limits outcrossing opportunities in plants. Baker’s law predicts an enrichment of uniparental reproduction in habitats colonized via long-distance dispersal, such as volcanic islands. To test it, we analyzed reproductive traits at multiple hierarchical levels and compared seed-set after selfing and crossing experiments in both island and mainland populations of Limonium lobatum, a widespread species that Baker assumed to be self-incompatible because it had been described as pollen-stigma dimorphic, i.e., characterized by floral morphs differing in pollen-surface morphology and stigma-papillae shape that are typically self-incompatible. We discovered new types and combinations of pollen and stigma traits hitherto unknown in the literature on pollen-stigma dimorphism and a lack of correspondence between such combinations and pollen compatibility. Contrary to previous reports, we conclude that Limonium lobatum comprises both self-compatible and self-incompatible plants characterized by both known and previously undescribed combinations of reproductive traits. Most importantly, plants with novel combinations are overrepresented on islands, selfed seed-set is higher in islands than the mainland, and insular plants with novel pollen-stigma trait-combinations disproportionally contribute to uniparental reproduction on islands. Our results thus support Baker’s law, connecting research on reproductive and island biology

Low genetic diversity and high levels of inbreeding in the Sinai primrose ( Primula boveana) , a species on the brink of extinction

The Sinai primrose (Primula boveana) is one of the most endangered plant species worldwide, with less than 200 wild individuals surviving in the Sinai mountains of Egypt. There has been a decline in both the number and size of its populations in recent times, possibly caused by threats that include habitat aridification and the impact of human activities. Studying the standing genetic variation and extent of inbreeding of P. boveana is necessary for the design of appropriate conservation strategies for this species. In the present work, we used a set of seven, recently developed, polymorphic microsatellite markers to characterize the genetic variation and levels of inbreeding of the extant populations of P. boveana. We found low levels of genetic variation (H T=0.470), high differentiation between populations (F ST=0.737, R ST=0.935), and very elevated levels of inbreeding (F=0.862) due to recurrent selfing. These results may be the reflection of low levels of genetic variation and high levels of inbreeding over a long evolutionary period, suggesting that the current genetic pool of the species may enable P. boveana to persist in a habitat where water availability and pollinator services are restricted. Nevertheless, in sight of its rapidly dwindling abundance, it seems prudent to adopt swift measures, including habitat restoration and ex-situ conservation, to prevent the impending extinction of this emblematic species

Geo-Climatic Changes and Apomixis as Major Drivers of Diversification in the Mediterranean Sea Lavenders (Limonium Mill.)

The Mediterranean realm, comprising the Mediterranean and Macaronesian regions, has long been recognized as one of the world’s biodiversity hotspots, owing to its remarkable species richness and endemism. Several hypotheses on biotic and abiotic drivers of species diversification in the region have been often proposed but rarely tested in an explicit phylogenetic framework. Here, we investigate the impact of both species-intrinsic and -extrinsic factors on diversification in the species-rich, cosmopolitan Limonium, an angiosperm genus with center of diversity in the Mediterranean. First, we infer and time-calibrate the largest Limonium phylogeny to date. We then estimate ancestral ranges and diversification dynamics at both global and regional scales. At the global scale, we test whether the identified shifts in diversification rates are linked to specific geological and/or climatic events in the Mediterranean area and/or asexual reproduction (apomixis). Our results support a late Paleogene origin in the proto-Mediterranean area for Limonium, followed by extensive in situ diversification in the Mediterranean region during the late Miocene, Pliocene, and Pleistocene. We found significant increases of diversification rates in the “Mediterranean lineage” associated with the Messinian Salinity Crisis, onset of Mediterranean climate, Plio-Pleistocene sea-level fluctuations, and apomixis. Additionally, the Euro-Mediterranean area acted as the major source of species dispersals to the surrounding areas. At the regional scale, we infer the biogeographic origins of insular endemics in the oceanic archipelagos of Macaronesia, and test whether woodiness in the Canarian Nobiles clade is a derived trait linked to insular life and a biotic driver of diversification. We find that Limonium species diversity on the Canary Islands and Cape Verde archipelagos is the product of multiple colonization events followed by in situ diversification, and that woodiness of the Canarian endemics is indeed a derived trait but is not associated with a significant shift to higher diversification rates. Our study expands knowledge on how the interaction between abiotic and biotic drivers shape the uneven distribution of species diversity across taxonomic and geographical scales.info:eu-repo/semantics/publishedVersio

The unconventional peridotite-related Mg-Fe-B skarn of the el robledal, SE Spain

The El Robledal deposit is a Mg-Fe-B skarn hosted in a dismembered block from the footwall contact of the Ronda orogenic peridotites in the westernmost part of the Betic Cordillera. The skarn is subdivided into two different zones according to the dominant ore mineral assemblage: (1) the ludwigite–magnetite zone, hosted in a completely mineralized body along with metasomatic forsterite, and (2) the magnetite–szaibelyite zone hosted in dolomitic marbles. In the ludwigite–magnetite zone, the massive mineralization comprises ludwigite (Mg2Fe3+(BO3)O2), Mg-rich magnetite, and magnetite, with minor amounts of kotoite (Mg3(BO3)2), szaibelyite (MgBO2(OH)), accessory schoenfliesite (MgSn4+(OH)6), and pentlandite. The ratio of ludwigite–magnetite decreases downwards in the stratigraphy of this zone. In contrast, the mineralization in the magnetite–szaibelyite zone is mainly composed of irregular and folded magnetite pods and bands with pull-apart fractures, locally associated with a brucite-, szaibelyite-, and serpentine-rich groundmass. The set of inclusions identified within these ore minerals, using a combination of a focused ion beam (FIB) and high-resolution transmission electron microscope (HRTEM), supports the proposed evolution of the system and reactions of the mineral formation of the skarn. The analysis of the microstructures of the ores by means of electron backscatter diffraction (EBSD) allowed for the determination that the ores experienced ductile deformation followed by variable degrees of recrystallization and annealing. We propose a new classification of the deposit as well as a plausible genetic model in a deposit where the heat source and the ore-fluid source are decoupled

Electronic plasma diffusion with radiation reaction force and time-dependent electric field

In this work the explicit solution of the electronic plasma diffusion with radiation reaction force, under the action of an exponential decay external electric field is given. The electron dynamics is described by a classical generalized Langevin equation characterized by an Ornstein-Uhlenbeck-type friction memory kernel, with an effective memory time which accounts for the effective thermal interaction between the electron and its surroundings (thermal collisions between electrons + radiation reaction force). The incident electric field exerts an electric force on the electron, which in turn can induce an additional damping to the braking radiation force, allowing a delay in the electron characteristic time. This fact allows that the effective memory time be finite and positive, and as a consequence, obtaining physically admissible solutions of the stochastic Abraham-Lorentz-like equation. It is shown that the diffusion process is quasi-Markovian which includes the radiation effects.Comment: 16 pages, 8 figure

Deconjugative α-alkylation of cyclohexenecarboxaldehydes: An access to diverse terpenoids

A general and efficient method for the deconjugative α-alkylation of α,β-unsaturated aldehydes promoted by a synergistic effect between tBuOK and NaH, which considerably increases the reaction rate under mild conditions, is reported. The β,γ-unsaturated aldehyde, resulting from the α-alkylation, is transformed in high yield into the corresponding allyl acetate via a lead(IV) acetate-mediated oxidative fragmentation. This strategy could be used for the construction of the carbon skeleton of a wide variety of alkyl or arylterpenoids