800 research outputs found
Acute effects of different warm-up protocols on highly skilled golfers’ drive performance
Previous research has highlighted the positive effect that different warm-up protocols have on golf performance (e.g. Sorbie et al., 2016; Tilley & MacFarlane, 2012) with the design of warm-ups and programmes targeting and improving golf performance through the activation and development of specific muscle groups. This study aimed to examine the acute effects of two warm-up protocols on golf drive performance in comparison to a control condition. Using a randomised counter-balanced design over three testing sessions, twenty-three highly skilled golfers completed the control, dynamic and resistance-band warm-up conditions. Following each condition, a GC2 launch monitor was used to record ball velocity and other launch parameters of ten shots hit with the participants own driver. A repeated-measures ANOVA found significant increases in ball velocity (ηp² = .217) between the control and both the dynamic and resistance-band warm-up conditions but no difference between these latter two, and a reduction in launch angle between control and dynamic conditions. The use of either a dynamic stretching or resistance-band warm-up can have acute benefits on ball velocity but golfers should liaise with a PGA Professional golf coach to effectively integrate this into their golf driving performance
Discordant phylogenomic placement of Hydnoraceae and Lactoridaceae within Piperales using data from all three genomes
Original ResearchPhylogenetic relationships within the magnoliid order Piperales have been studied
extensively, yet the relationships of the monotypic family Lactoridaceae and the
holoparasitic Hydnoraceae to the remainder of the order remain a matter of debate.
Since the first confident molecular phylogenetic placement of Hydnoraceae among
Piperales, different studies have recovered various contradictory topologies. Most
phylogenetic hypotheses were inferred using only a few loci and have had incomplete
taxon sampling at the genus level. Based on these results and an online survey of
taxonomic opinion, the Angiosperm Phylogeny Group lumped both Hydnoraceae and
Lactoridaceae in Aristolochiaceae; however, the latter family continues to have unclear
relationships to the aforementioned taxa. Here we present extensive phylogenomic tree
reconstructions based on up to 137 loci from all three subcellular genomes for all genera
of Piperales. We infer relationships based on a variety of phylogenetic methods, explore
instances of phylogenomic discordance between the subcellular genomes, and test
alternative topologies. Consistent with these phylogenomic results and a consideration
of the principles of phylogenetic classification, we propose to exclude Hydnoraceae
and Lactoridaceae from the broad circumscription of Aristolochiaceae, and instead
favor recognition of four monophyletic and morphologically well circumscribed families
in the perianth-bearing Piperales: Aristolochiaceae, Asaraceae, Hydnoraceae, and
Lactoridaceae, with a total of six families in the orderinfo:eu-repo/semantics/publishedVersio
Monocot fossils suitable for molecular dating analyses
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111920/1/boj12233.pd
Molecular Phylogenetics of Bromus (Poaceae: Pooideae) Based on Chloroplast and Nuclear DNA Sequence Data
We conducted a phylogenetic analysis to characterize relationships among Bromus and test the monophyly of five of the seven morphologically distinct groups within Bromus (Poaceae: Pooideae) that have been treated as sections, subgenera, or genera. We sequenced the chloroplast trnL (UAA) intron, the 3\u27-end of the chloroplast ndhF gene, and the internal transcribed spacers (ITS) of the nuclear ribosomal DNA region for 46 species that represent a large proportion of the morphological and geographical diversity in the genus. Independent analyses of plastid and nuclear ribosomal data identified several lineages in Bromus, but there is some evidence of incongruence between these linkage groups. Nuclear ribosomal trees indicate that two clades comprising some North and South American species of sect. Bromopsis are the successive sister groups of the rest of the genus, and that Old World species of sect. Bromopsis are more closely related to sects. Ceratochloa and Neobromus than they are to the remaining North American species of sect. Bromopsis. In contrast, plastid trees indicate a close relationship between Old World and some North American species of sect. Bromopsis. In the nuclear ribosomal trees, sects. Genea and Bromus (if sect. Triniusia is included within it, as treated by most authors) are monophyletic and not closely related. In the plastid trees, species of these two sections are intermixed, supporting a hybrid origin for B. pectinatus. The monophyly of sect. Ceratochloa is supported in the plastid and nuclear ribosomal trees, and the monophyly of sect. Neobromus is robustly supported in the nuclear ribosomal trees. Current classification schemes do not reflect phylogenetic relationships in Bromus. Tentative evidence of conflict among nuclear and plastid data partitions needs clarification with more robustly supported plastid and nuclear ribosomal gene trees
Heterologous oligonucleotide microarrays for transcriptomics in a non-model species; a proof-of-concept study of drought stress in Musa
<p>Abstract</p> <p>Background</p> <p>'Systems-wide' approaches such as microarray RNA-profiling are ideally suited to the study of the complex overlapping responses of plants to biotic and abiotic stresses. However, commercial microarrays are only available for a limited number of plant species and development costs are so substantial as to be prohibitive for most research groups. Here we evaluate the use of cross-hybridisation to Affymetrix oligonucleotide GeneChip<sup>® </sup>microarrays to profile the response of the banana (<it>Musa </it>spp.) leaf transcriptome to drought stress using a genomic DNA (gDNA)-based probe-selection strategy to improve the efficiency of detection of differentially expressed <it>Musa </it>transcripts.</p> <p>Results</p> <p>Following cross-hybridisation of <it>Musa </it>gDNA to the Rice GeneChip<sup>® </sup>Genome Array, ~33,700 gene-specific probe-sets had a sufficiently high degree of homology to be retained for transcriptomic analyses. In a proof-of-concept approach, pooled RNA representing a single biological replicate of control and drought stressed leaves of the <it>Musa </it>cultivar 'Cachaco' were hybridised to the Affymetrix Rice Genome Array. A total of 2,910 <it>Musa </it>gene homologues with a >2-fold difference in expression levels were subsequently identified. These drought-responsive transcripts included many functional classes associated with plant biotic and abiotic stress responses, as well as a range of regulatory genes known to be involved in coordinating abiotic stress responses. This latter group included members of the ERF, DREB, MYB, bZIP and bHLH transcription factor families. Fifty-two of these drought-sensitive <it>Musa </it>transcripts were homologous to genes underlying QTLs for drought and cold tolerance in rice, including in 2 instances QTLs associated with a single underlying gene. The list of drought-responsive transcripts also included genes identified in publicly-available comparative transcriptomics experiments.</p> <p>Conclusion</p> <p>Our results demonstrate that despite the general paucity of nucleotide sequence data in <it>Musa </it>and only distant phylogenetic relations to rice, gDNA probe-based cross-hybridisation to the Rice GeneChip<sup>® </sup>is a highly promising strategy to study complex biological responses and illustrates the potential of such strategies for gene discovery in non-model species.</p
Mycoheterotrophic<em> Epirixanthes</em> (Polygalaceae) has a typical angiosperm mitogenome but unorthodox plastid genomes
Localized retroprocessing as a model of intron loss in the plant mitochondrial genome
Loss of introns in plant mitochondrial genes is commonly explained by retroprocessing. Under this model, an mRNA is reverse transcribed and integrated back into the genome, simultaneously affecting the contents of introns and edited sites. To evaluate the extent to which retroprocessing explains intron loss, we analyzed patterns of intron content and predicted RNA editing for whole mitochondrial genomes of 30 species in the monocot order Alismatales. In this group, we found an unusually high degree of variation in the intron content, even expanding the hitherto known variation among angiosperms. Some species have lost some two-third of the cis-spliced introns. We found a strong correlation between intron content and editing frequency, and detected 27 events in which intron loss is consistent with the presence of nucleotides in an edited state, supporting retroprocessing. However, we also detected seven cases of intron loss not readily being explained by retroprocession. Our analyses are also not consistent with the entire length of a fully processed cDNA copy being integrated into the genome, but instead indicate that retroprocessing usually occurs for only part of the gene. In some cases, several rounds of retroprocessing may explain intron loss in genes completely devoid of introns. A number of taxa retroprocessing seem to be very common and a possibly ongoing process. It affects the entire mitochondrial genome
Great Canadian Lagerstätten 3. Late Ordovician Konservat-Lagerstätten in Manitoba
Konservat-Lagerstätten, deposits in which soft-bodied or lightly sclerotized fossils are preserved, are very rare in Ordovician strata. Three significant sites are known from Upper Ordovician rocks in Manitoba: at Cat Head – McBeth Point, William Lake, and Airport Cove. These sites are in two distinct sedimentary basins: the former two are in the Williston Basin, while the latter is in the Hudson Bay Basin. All three sites contain marine fossils, but each has a different assemblage that contributes a distinct piece of the diversity picture. Important groups represented at one or more of the sites include seaweeds (algae), sponges, cnidarian medusae (jellyfish), conulariids, trilobites, eurypterids, xiphosurids (horseshoe crabs), and pycnogonids (‘sea spiders’). The different biotas reflect depositional conditions at each site. Many of the fossils are unknown elsewhere in the Ordovician at the family level or higher. The province of Manitoba therefore makes a significant contribution to knowledge of Late Ordovician biodiversity.SOMMAIRELes lagerstätten de conservation, ces sédiments contenant des fossiles d’organismes à corps mou ou légèrement sclérotisés particulièrement bien conservés, sont très rares dans les strates ordoviciennes. Trois sites d’importance sont connus dans des roches de l'Ordovicien supérieur à Cat Head, Manitoba, soit McBeth Point, William Lake et Airport Cove. Ces sites sont situés dans deux bassins sédimentaires distincts : les deux premiers sont situés dans le bassin de Williston, tandis que le second est situé dans le bassin de la baie d'Hudson. Les trois sites contiennent des fossiles marins, mais chacun présente un assemblage différent, chacun montrant une composante distincte de la diversité biologique d’alors. Les groupes les plus importants représentés, dans un ou plusieurs de ces sites, sont les algues, les éponges, les cnidarian medusae (méduses), les conularides, les trilobites, les euryptérides, xiphosurides (limules) et pycnogonides. Les différents biotopes reflètent les conditions de dépôt de chaque site. Nombre de ces fossiles sont inconnus ailleurs dans l'Ordovicien, au niveau de la famille ou du taxon supérieur de la classification. Ainsi, la province du Manitoba offre-t-elle une contribution importante à la connaissance de la biodiversité de l'Ordovicien supérieur
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