133 research outputs found
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Phylogenetics of the Pezizaceae, with an Emphasis on Peziza
Phylogenetic relationships among members of the Pezizaceae were studied using 90 partial LSU rDNA sequences from 51 species of Peziza and 20 species from 8 additional epigeous genera of the Pezizaceae, viz. Boudiera, Iodophanus, Iodowynnea, Kimbropezia, Pachyella, Plicaria, Sarcosphaera and Scabropezia, and 5 hypogeous genera, viz. Amylascus, Cazia, Hydnotryopsis, Ruhlandiella and Tirmania. To test the monophyly of the Pezizaceae and the relationships to the genera Marcelleina and Pfistera (Pyronemataceae), 6 species from the families Ascobolaceae, Morchellaceae and Pyronemataceae were included. Maximum parsimony and maximum likelihood analyses of these sequences suggest that the Pezizaceae is paraphyletic, because the non-amyloid Marcelleina is nested within it. If Marcelleina were transferred to the Pezizaceae, then the family would be monophyletic. Although the Pezizaceae is traditionally characterized by amyloid asci, our results indicate that the amyloid reaction is a symplesiomorphy, which has been lost in some lineages, e.g., in those including Marcelleina and Cazia. Nodes deep in the tree could not be resolved, but 7 groups of species (I-VII) are generally well supported or present in all trees. Peziza species, which constitute the core of the family, are present in all groups except group III, confirming the non-monophyly of the genus. The analyses suggest that the other included genera of the Pezizaceae are all nested within Peziza, the placement of Iodophanus being unresolved. The morphologically distinct Peziza gerardii, which forms a clade with Marcelleina, appears to be the sister group to the rest of the Pezizaceae. Morphological features were studied and evaluated in the context of the phylogeny. Distinct types of ascus amyloid reactions were found to support different rDNA lineages, e.g., a distinct amyloid ring zone at the apex is a synapomorphy for group IV, an intense and unrestricted amyloid reaction of the apex is mostly found in group VI, and asci that are weakly or diffusely amyloid in the entire length are present in group II. Other morphological features, such as spore surface relief, guttulation, excipulum structure and pigments, while not free from homoplasy, do support the groupings. Anamorphs likewise provide clues to higher-order relationships within the Pezizaceae. Several macro- and micromorphological features, however, appear to have evolved several times independently, including ascomatal form and habit (epigeous, semihypogeous or hypogeous), spore discharge mechanisms, and spore shape. Parsimony-based optimization of character states on our phylogenetic trees suggested that transitions to truffle and truffle-like forms evolved at least three times within the Pezizaceae (in group III, V and VI). The 9 hypogeous species included are nested in lineages with epigeous pezizaceous taxa. Species with apothecia of various shapes and with forcible spore discharge are spread among all groups and the apothecium is suggested to be symplesiomorphic in the Pezizaceae. The results indicate that the apothecia forming Pezizaceae have given rise to at least 3 different forms of hypogeous ascomata without forcible spore discharge: ptychothecia, stereothecia and exothecia.Organismic and Evolutionary Biolog
Phylogenetic Diversity in the Core Group of Peziza Inferred from ITS Sequences and Morphology
Species delimitation within the core group of Peziza is highly controversial. The group, typified by P. vesiculosa, is morphologically coherent and in previous analyses of LSU rDNA sequences it formed a highly supported clade. Phylogenetic diversity and species limits were investigated within the group using sequences from the complete ITS region (ITSI-5.8S-ITS2). Eighty-three specimens were selected for molecular study from a larger sample of material studied morphologically to explore the intra- and interspecific variation of each putative species. The sister group taxon, P. ampelina was used as the outgroup and two specimens of P. subcitrina were additionally included. Seven independent lineages of rDNA were identified (I-VII), each representing one to several species. These lineages form two larger clades, A (II, and I or III) and B (IV-VII), supported by macromorphology: small (generally less than 2 cm), shallowly cup- to disc-shaped apothecia (A) and large (up to 15 cm), deeply cup-shaped to expanded apothecia (B). The overall exciple structure (a stratified or non-stratified medullary layer) and to some degree spore surface relief, likewise support the groupings. Clade A contains taxa with smooth or nearly smooth spores (except for P. lohjaensis), while clade B contains taxa with a range of spore ornamentations, from smooth, finely warty to distinctly warty, and spiny. The position of groups I (P. vesiculosa and P. ammophila) and III (P. lohjaensis) are uncertain, and these taxa also deviate morphologically from the other clade A members. The following species are recognized based on morphology and ITS rDNA analyses: P. ammophila and P. vesiculosa (I); P. alcis, P. ampliata, P. domiciliana, P. fimeti, P. nivalis, and a number of putative species or intraspecific entities (II); P. lohjaensis (III); P. sp. c (IV); P. arvernensis (V); P. echinispora and P. sp. d (VI); and P. varia (VII). The nomenclature of these species is analyzed and taxa are typified as necessary. Based on ITS and morphology, we found no justification for recognizing more than one species in the 'P. varia complex', including 27 specimens that have been referred to under the names P. cerea, P. micropus and P. repanda, from an array of substrates and different geographical areas. Morphological characters previously used to delimit species within this complex, such as colour variation of the apothecia, presence or absence of a stipe, stratified or non-stratified medullary exciple (or thickness of the excipular layers), cell types in the outermost exciple and moniliform vs filiform paraphyses were not correlated with the subgroups supported by ITS analyses and appeared to be plastic. Therefore, P. cerea and P. micropus are placed in synonymy with P. varia. The name P. repanda is rejected. Levels of sequence divergence were low within group II, comprising 33 small apothecial specimens. Twelve fine-scale lineages were identified, but the analyses did not resolve relationships among these. P. granulosa sensu Boudier is considered a synonym of P. fimeti. These have previously been distinguished mainly by occurrence on various soil types, including burnt soil and soil mixed with sawdust or woodchips vs on dung. The substrate and habitat have been much emphasized in the taxonomy of Peziza, but the results obtained here indicate that populations on a diverse array of substrates may be closely related, or indeed, conspecific.Organismic and Evolutionary Biolog
Examination of the gait pattern based on adjusting and resulting components of the stride-to-stride variability:Proof of concept
Abstract Background Stride-to-stride variability may be used as an indicator in the assessment of gait performance, but the evaluation of this parameter is not trivial. In the gait pattern, a deviation in one stride must be corrected within the next strides (elemental variables) to ensure a steady gait (performance variable). The variance in these elemental and performance variables may therefore be evaluated as adjusting and resulting components of variability. We explored this approach to gait evaluation by matching the velocity of one stride to a subsequent stride with four different time lags ranging from 0.5 to 2 strides with 0.5 stride increments. The time lag values corresponded to the following contralateral stride, the following ipsilateral stride, the second following contralateral stride and the second following ipsilateral stride. Methods Twenty asymptomatic young adults walked on an instrumented treadmill at their preferred gait speed. The stride velocity was calculated, and variances in the stride-to-stride differences and in the stride-to-stride sums represented the adjusting and the resulting variances, respectively. A ratio between these values of greater than one indicated a meaningful stride-to-stride interaction. Results For the four time lags (0.5, 1, 1.5, and 2 strides), the adjusting/resulting variance ratios (mean and CI 95%) were 1.0 (0.8–1.2), 2.9 (2.3–3.6), 1.2 (1.0–1.4) and 1.2 (0.9–1.4), respectively. Conclusions This new approach to the evaluation of stride-to-stride variability suggests that gait velocity adjustments occurred within one full stride cycle during treadmill walking among asymptomatic young adults. The validity of the approach needs to be tested in over-ground walking
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Sociodemographic characteristics associated with physical activity barrier perception among manual wheelchair users
Individuals with disabilities are sub-optimally active and at increased risk for chronic diseases. Limited knowledge exists about how differences among wheelchair-dependent individuals may affect their perception of physical activity barriers.
We examined whether the perception of physical activity barriers are associated with wheelchair user sociodemographic characteristics.
Danish manual wheelchair users (MWCUs) (N = 181; 52.5% females, mean ± SD: age 48 ± 14 yrs) completed the ‘Barriers to Physical Activity Questionnaire for People with Mobility Impairments’ (BPAQ-MI) online. The BPAQ-MI queries physical activity barriers in four domains (intrapersonal, interpersonal, organizational, and community) and eight subdomains. Participant characteristics evaluated as potentially associated with physical activity barriers included age, sex, years in chair, body mass index (BMI), spinal cord injury (SCI) (if any), education, employment, and resident city size. Simple linear regression (step 1) and multiple regression models (step 2) were created to assess associations between MWCU characteristics and barriers.
Multiple regression models revealed that MWCUs who were obese, who did not complete high school, or were unemployed rated physical activity barriers higher across several subdomains (all r2≤0.226, p<0.05). Resident city size was associated with safety subdomain barrier impact (r2=0.039, p<0.05). Sex, age, years in chair and SCI were not associated with any barrier domains (all p ≥ 0.064).
Our results provide new evidence that MWCUs with BMI ≥30; who are not employed; or who only have completed high school, may need special consideration and resources to overcome distinct physical activity barriers. Behavioral strategies and interventions focusing on reducing physical activity barriers should be tailored to the individuals above
Wood-inhabiting fungal responses to forest naturalness vary among morpho-groups
The general negative impact of forestry on wood-inhabiting fungal diversity is well recognized, yet the effect of forest naturalness is poorly disentangled among different fungal groups inhabiting dead wood of different tree species. We studied the relationship between forest naturalness, log characteristics and diversity of different fungal morpho-groups inhabiting large decaying logs of similar quality in spruce dominated boreal forests. We sampled all non-lichenized fruitbodies from birch, spruce, pine and aspen in 12 semi-natural forest sites of varying level of naturalness. The overall fungal community composition was mostly determined by host tree species. However, when assessing the relevance of the environmental variables separately for each tree species, the most important variable varied, naturalness being the most important explanatory variable for fungi inhabiting pine and aspen. More strikingly, the overall species richness increased as the forest naturalness increased, both at the site and log levels. At the site scale, the pattern was mostly driven by the discoid and pyrenoid morpho-groups inhabiting pine, whereas at the log scale, it was driven by pileate and resupinate morpho-groups inhabiting spruce. Although our study demonstrates that formerly managed protected forests serve as effective conservation areas for most wood-inhabiting fungal groups, it also shows that conservation planning and management should account for group- or host tree -specific responses.Peer reviewe
Penile vibratory stimulation in the recovery of urinary continence and erectile function after nerve‐sparing radical prostatectomy: a randomized, controlled trial
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/107551/1/bju12501.pd
Morphological traits predict host-tree specialization in wood-inhabiting fungal communities
Tree species is one of the most important determinants of wood-inhabiting fungal community composition, yet its relationship with fungal reproductive and dispersal traits remains poorly understood. We studied fungal communities (total of 657 species) inhabiting broadleaved and coniferous dead wood (total of 192 logs) in 12 semi-natural boreal forests. We utilized a trait-based hierarchical joint species distribution model to examine how the relationship between dead wood quality and species occurrence correlates with reproductive and dispersal morphological traits. Broadleaved trees had higher species richness than conifers, due to discomycetoids and pyrenomycetoids specializing in them. Resupinate and pileate species were generally specialized in coniferous dead wood. Fungi inhabiting broadleaved trees had larger and more elongated spores than fungi in conifers. Spore size was larger and spore shape more spherical in species occupying large dead wood units. These results indicate the selective effect of dead wood quality, visible not only in species diversity, but also in reproductive and dispersal traits. (C) 2019 Elsevier Ltd and British Mycological Society. All rights reserved.peerReviewe
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