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1.
Plants (Basel) ; 11(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35406819

RESUMO

Fern phylogeographic studies have mostly focused on the influence of the Pleistocene climate on fern distributions and the prevalence of long-distance dispersal. The effect of pre-Pleistocene events on the distributions of fern species is largely unexplored. Here, we elucidate a hypothetical scenario for the evolutionary history of Vandenboschia speciosa, hypothesised to be of Tertiary palaeotropical flora with a peculiar perennial gametophyte. We sequenced 40 populations across the species range in one plastid region and two variants of the nuclear gapCp gene and conducted time-calibrated phylogenetic, phylogeographical, and species distribution modelling analyses. Vandenboschia speciosa is an allopolyploid and had a Tertiary origin. Late Miocene aridification possibly caused the long persistence in independent refugia on the Eurosiberian Atlantic and Mediterranean coasts, with the independent evolution of gene pools resulting in two evolutionary units. The Cantabrian Cornice, a major refugium, could also be a secondary contact zone during Quaternary glacial cycles. Central European populations resulted from multiple post-glacial, long-distance dispersals. Vandenboschia speciosa reached Macaronesia during the Pliocene-Pleistocene, with a phylogeographical link between the Canary Islands, Madeira, and southern Iberia, and between the Azores and northwestern Europe. Our results support the idea that the geological and climate events of the Late Miocene/Early Pliocene shifted Tertiary fern distribution patterns in Europe.

2.
Int J Sports Physiol Perform ; 14(10): 1442-1446, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30958044

RESUMO

OBJECTIVE: To compare the accuracy of different devices to predict the bench-press 1-repetition maximum (1RM) from the individual load-velocity relationship modeled through the multiple- and 2-point methods. METHODS: Eleven men performed an incremental test on a Smith machine against 5 loads (45-55-65-75-85%1RM), followed by 1RM attempts. The mean velocity was simultaneously measured by 1 linear velocity transducer (T-Force), 2 linear position transducers (Chronojump and Speed4Lift), 1 camera-based optoelectronic system (Velowin), 2 inertial measurement units (PUSH Band and Beast Sensor), and 1 smartphone application (My Lift). The velocity recorded at the 5 loads (45-55-65-75-85%1RM), or only at the 2 most distant loads (45-85%1RM), was considered for the multiple- and 2-point methods, respectively. RESULTS: An acceptable and comparable accuracy in the estimation of the 1RM was observed for the T-Force, Chronojump, Speed4Lift, Velowin, and My Lift when using both the multiple- and 2-point methods (effect size ≤ 0.40; Pearson correlation coefficient [r] ≥ .94; standard error of the estimate [SEE] ≤ 4.46 kg), whereas the accuracy of the PUSH (effect size = 0.70-0.83; r = .93-.94; SEE = 4.45-4.80 kg), and especially the Beast Sensor (effect size = 0.36-0.84; r = .50-.68; SEE = 9.44-11.2 kg), was lower. CONCLUSIONS: These results highlight that the accuracy of 1RM prediction methods based on movement velocity is device dependent, with the inertial measurement units providing the least accurate estimate of the 1RM.

3.
J Strength Cond Res ; 33(5): 1258-1265, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31034462

RESUMO

Pérez-Castilla, A, Piepoli, A, Delgado-García, G, Garrido-Blanca, G, and García-Ramos, A. Reliability and concurrent validity of seven commercially available devices for the assessment of movement velocity at different intensities during the bench press. J Strength Cond Res 33(5): 1258-1265, 2019-The aim of this study was to compare the reliability and validity of 7 commercially available devices to measure movement velocity during the bench press exercise. Fourteen men completed 2 testing sessions. One-repetition maximum (1RM) in the bench press exercise was determined in the first session. The second testing session consisted of performing 3 repetitions against 5 loads (45, 55, 65, 75, and 85% of 1RM). The mean velocity was simultaneously measured using an optical motion sensing system (Trio-OptiTrack; "gold-standard") and 7 commercially available devices: 1 linear velocity transducer (T-Force), 2 linear position transducers (Chronojump and Speed4Lift), 1 camera-based optoelectronic system (Velowin), 1 smartphone application (PowerLift), and 2 inertial measurement units (IMUs) (PUSH band and Beast sensor). The devices were ranked from the most to the least reliable as follows: (a) Speed4Lift (coefficient of variation [CV] = 2.61%); (b) Velowin (CV = 3.99%), PowerLift (3.97%), Trio-OptiTrack (CV = 4.04%), T-Force (CV = 4.35%), and Chronojump (CV = 4.53%); (c) PUSH band (CV = 9.34%); and (d) Beast sensor (CV = 35.0%). A practically perfect association between the Trio-OptiTrack system and the different devices was observed (Pearson's product-moment correlation coefficient (r) range = 0.947-0.995; p < 0.001) with the only exception of the Beast sensor (r = 0.765; p < 0.001). These results suggest that linear velocity/position transducers, camera-based optoelectronic systems, and the smartphone application could be used to obtain accurate velocity measurements for restricted linear movements, whereas the IMUs used in this study were less reliable and valid.


Assuntos
Teste de Esforço/instrumentação , Teste de Esforço/normas , Força Muscular/fisiologia , Treinamento Resistido/instrumentação , Adulto , Coleta de Dados , Teste de Esforço/métodos , Humanos , Masculino , Aplicativos Móveis , Movimento (Física) , Reprodutibilidade dos Testes , Treinamento Resistido/métodos , Transdutores , Adulto Jovem
4.
Front Plant Sci ; 10: 303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30949188

RESUMO

Late Neogene and Quaternary climatic oscillations have greatly shaped the genetic structure of the Mediterranean Basin flora, with mountain plant species tracking warm interglacials/cold glacials by means of altitudinal shifts instead of broad latitudinal ones. Such dynamics may have enhanced population divergence but also secondary contacts. In this paper, we use a case example of subsection Willkommia of Centaurea (comprising three narrowly distributed endemic species, Centaurea gadorensis, C. pulvinata, and C. sagredoi) to test for reticulate evolution and recurrent hybridizations between nearby populations. For this, we combine analyses of genetic diversity and structuring, gene flow and spatial correlation, and ecological niche modeling. Our results support the contention that the current genetic structure of the three species is the result of historical gene flow at sites of secondary contact during the glacial periods, followed by isolation after the retraction of populations to the middle-upper areas of the mountains during the interglacial periods. The extent and direction of the gene flow was determined largely by the location of the populations on mountainsides oriented toward the same valley or toward different valleys, suggesting the intermountain valleys as the areas where secondary contacts occurred.

5.
Am J Bot ; 99(3): 517-28, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22334448

RESUMO

PREMISE OF THE STUDY: Little research has been done at the molecular level on the tribe Fumarieae (Papaveraceae). Papaveraceae is a model plant group for studying evolutionary patterns despite the lack of a reference phylogeny for this tribe. We investigated the phylogenetic relationships within the tribe to complete the molecular data for this family in order to help understand its character evolution and biogeographic pattern. METHODS: We used maximum-parsimony and Bayesian approaches to analyze five DNA regions for 25 species representing 10 of the 11 Fumarieae genera and five outgroups. Evolutionary pathways of four characters (habit, life span, type of fruit, and number of seeds per fruit) were inferred on the phylogeny using parsimony. The ancestral distribution areas were reconstructed using dispersal-vicariance analysis. KEY RESULTS: Fumarieae is monophyletic and includes three groups that agree with the morphology-based subtribes: Discocapninae, Fumariinae, and Sarcocapninae. Within subtribes, the relationships among genera were different from those obtained with morphological data. Annual life span, nonchasmophytic habit, and a several-seeded capsule were the basal character states for the tribe. The ancestor occupied a continuous area between West Eurasia and Africa. Vicariances explain the divergence between lineages Discocapninae (South Africa) and Fumariinae-Sarcocapninae (Mediterranean), and the disjunction of Fumariinae (Mediterranean-Central Asia). CONCLUSIONS: Molecular phylogeny confirms the subtribal classification of Fumarieae based on morphology. However it provides different results regarding the relationships among genera within each subtribe, which affects the inference of the evolutionary pathway followed by the four selected characters. The disjunct distribution of the tribe is explained by different vicariance scenarios.


Assuntos
DNA de Cloroplastos/genética , Papaveraceae/genética , Filogenia , Demografia , Filogeografia
6.
Mol Ecol Resour ; 9(3): 830-2, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21564759

RESUMO

We report on the isolation and characterization of eight microsatellite markers from enriched libraries for the critically endangered Atropa baetica. These are the first microsatellite loci reported for Atropa species. The total number of alleles found was 18, the expected heterozygosity ranged from 0.198 to 0.505. These markers will be useful to establish the real census of individuals and the genetic diversity both within and among the different populations of A. baetica.

7.
Gene ; 404(1-2): 80-92, 2007 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17905542

RESUMO

Within the genus Centaurea (subtribe Centaureinae, tribe Cardueae, Compositae) hybridizations and reticulate-evolution phenomena have widely been recognized. This is especially true in the taxa included in the subgroup Acrolophus from the western Mediterranean area, in which recurrent hybridizations of parapatric ("microallopatric") lineages within the geographical range of a primary radiation have been suggested. The subgroup Acrolophus includes taxa from three sections (i.e. Acrolophus, Phalolepis and Willkommia), and, together with other subgroups, forms the named Jacea group (one of the three main groups into which Centaurea is divided). In this paper, we have studied the influence that the complex evolutionary scenario described for the Acrolophus subgroup from the western Mediterranean exerts on the evolutionary pattern of a satellite-DNA family, the HinfI family, which exists within the genomes of these taxa. To this end, we have analyzed the evolution of this satellite-DNA family in taxa from different taxonomic comparative levels: i) seven subspecies of the C. boissieri complex (one of which with two varieties) of the sect. Willkommia; ii) species of the sections Willkommia (10 species, 19 taxa), Acrolophus (two species), and Phalolepis (two species), all in the Acrolophus subgroup; iii) one external species to the Jacea group, C. granatensis from the group Acrocentron; iv) and species from other related genera from the Centaureinae subtribe (Phonus and Carthamus, both belonging to the Carthamus group). The influence of the suggested model for the origin and diversification of the Acrolophus subgroup is evidenced by the existence of three different HinfI satellite-DNA subfamilies coexisting in some genomes, and by the analysis that we have made by comparing site-by-site the transition stages in the process of concerted evolution between the sequences of the each subfamily. From this analysis, we can deduce that the HinfI repeated subfamilies evolved in a gradual manner, and that the different stages of concerted evolution fit quite well with the combined nuclear-chloroplast-DNA-deduced divergences and phylogeny of the subtribe Centaureinae. The HinfI satellite-DNA from the Carthamus species group (genera Carthamus and Phonus) and from the Acrocentron group (Centaurea granatensis) shows a high intraspecific conservation of the repeats, suggesting that the mechanisms producing concerted evolution have been efficient in these taxa. In addition, the comparison of individual nucleotide positions between related species shows a paucity in the spreading of variants in each subfamily with satellite-DNA divergence, an indication of a constant rate of homogenization of the repeated cluster. On the contrary, this trend is absent in the comparisons of the HinfI sequences from taxa of the subgroup Acrolophus. In this subgroup, we have found in this repetitive family similar representative average sequences for each taxon analyzed, polymorphic sites in each taxon being scant, most of them autapomorphic, representing early stages of genetic differentiation between taxa in the process of concerted evolution. The absence of concerted evolution was visualized by similar levels of intraspecific variation and interspecific divergence and by the lack of fixed species-diagnostic nucleotide sites. These facts might reflect the reticulate mode of evolution of Acrolophus.


Assuntos
Asteraceae/classificação , Asteraceae/genética , Centaurea/classificação , Centaurea/genética , DNA Satélite , Evolução Molecular , Sequência de Bases , DNA de Plantas/química , DNA de Plantas/genética , Desoxirribonucleases de Sítio Específico do Tipo II/química , Região do Mediterrâneo , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
8.
Mol Phylogenet Evol ; 43(1): 156-72, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17129737

RESUMO

Section Willkommia (Centaurea, Compositae) is endemic to the east-central portion of the Iberian Peninsula and northwestern Africa. The section has been included with sections Acrolophus and Phalolepis in the informal subgroup Acrolophus. We have used a molecular phylogenetic approach to test the hypothesis proposed by earlier authors that the diversification of section Willkommia involved a schizoendemic process from an ancestral syngameon. Comparative analysis of the transcribed spacer sequences of the nuclear ribosomal DNA (ITS and 3'ETS) regions reveals the presence of three different types of ribosomal sequences in the Acrolophus subgroup (referred to here as the Willkommia, Acrolophus-Phalolepis and Simulans ribotypes) which show a sectional-independent geographic structure. This evidence, together with the presence of additive polymorphic sites in the Willkommia sequences which agree with the geographic distribution of the taxa, suggests that members of section Willkommia and the western Mediterranean taxa of sections Acrolophus and Phalolepis fit a reticulate evolution model.


Assuntos
Centaurea/genética , Demografia , Evolução Molecular , Hibridização Genética , Modelos Genéticos , Filogenia , Composição de Bases , Sequência de Bases , Biologia Computacional , Primers do DNA , DNA Espaçador Ribossômico/genética , Variação Genética , Geografia , Funções Verossimilhança , Região do Mediterrâneo , Dados de Sequência Molecular , Análise de Sequência de DNA
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