The systematic position of Gradsteinia andicola Ochyra (Donrichardsiaceae, Bryopsida) : evidence from nrDNA internal transcribed spacer sequences

Nuclear ribosomal DNA internal transcribed spacer (ITS) 1/2 sequences of the Colombian endemic Gradsteinia andicola were determined and compared with those of 16 other species of the Hypnales (Amblystegiaceae, Brachytheciaceae, Hypnaceae, Plagiotheciaceae and Rhytidiaceae). In a maximum parsimony tree Gradsteinia andicola belongs to a well supported clade consisting of Amblystegium, Cratoneuron, Cratoneuropsis, Hypnobartlettia and Palustriella, and seems to be closely related to Cratoneuropsis relaxa from New Zealand. Gradsteinia andicola is therefore transferred to Amblystegiaceae, but the genus Gradsteinia is maintained. The systematic relationship of Amblystegiaceae and Donrichardsiaceae is discussed

New bryophyte taxon records for tropical countries 4

Nord Kivu: c. 6 km north of Lubero, on sandy soil of tree-shaded road cutting, c. 1800m, 0º 8' S, 29º 14' E, 11 Aug 1988. C.R. Stevenson Z 78f, det. E.W. Jones (BM, & herb. C.R. Stevenson). Growing mixed with Frullania serrata, Pilotrichella, Trachypodopsis, etc. Distrib.: Annobon, Bioko, Burundi, Cameroun, Kenya, Rwanda, Sao Tome, Tanzania

The Macaronesian endemic moss Andoa berthelotiana (Myuriaceae, Bryophyta): Phylogenetic relationships and cryptic speciation

The Macaronesian endemic pleurocarpous moss species Andoa berthelotiana occurs in the Madeira, Azores and Canary Islands archipelagos. It has a checkered taxonomic history with placements in different genera or, as monospecific genus Andoa, in different families, most frequently in the Hypnaceae. Earlier molecular phylogenetic analyses indicated a close relationship of Andoa with Ctenidium, Hyocomium and Myurium in a clade corresponding to Myuriaceae, which was supported in the present study based on a larger sampling and markers from all three genomes (chloroplast trnL-trnF, nuclear ribosomal ITS and mitochondrial nad5). Haplotype networks of the nad5 and ITS sequences as well as AFLP fingerprinting data revealed the existence of two intraspecific lineages in Andoa berthelotiana, one occurring in Madeira and the Canary Islands and the other in the Azores. The trnL-trnF haplotype network contradicts this geographic pattern, however, the position of the two mutations differentiating the trnL-trnF haplotypes suggests that they may not be phylogenetically informative. A detailed morphological analysis of plants from the Azores and Madeira indicates the existence of distinguishing characters that correspond with the two molecular lineages. However, the considerable morphological overlap observed would hamper the identification of specimens if both lineages were formally described as separate taxa. We therefore suggest treating the two lineages of Andoa as semi-cryptic species.info:eu-repo/semantics/publishedVersio

Proton Capture on ^{17}O and its astrophysical implications

The reaction $^{17}$O$(p,\gamma)^{18}$F influences hydrogen-burning nucleosynthesis in several stellar sites, such as red giants, asymptotic giant branch (AGB) stars, massive stars and classical novae. In the relevant temperature range for these environments ($T_{9}=0.01-0.4), the main contributions to the rate of this reaction are the direct capture process, two low lying narrow resonances ($E_{r}=65.1$and 183 keV) and the low-energy tails of two broad resonances ($E_{r}=557$and 677 keV). Previous measurements and calculations give contradictory results for the direct capture contribution which in turn increases the uncertainty of the reaction rate. In addition, very few published cross section data exist for the high energy region that might affect the interpretation of the direct capture and the contributions of the broad resonances in the lower energy range. This work aims to address these issues. The reaction cross section was measured in a wide proton energy range ($E_{c.m.}=345$- 1700 keV) and at several angles ($\theta_{lab}=0^{\circ},45^{\circ},90^{\circ},135^{\circ}$). The observed primary$\gamma$-transitions were used as input in an$R$-matrix code in order to obtain the contribution of the direct capture and the two broad resonances to the low-energy region. The extrapolated S-factor from the present data is in good agreement with the existing literature data in the low-energy region. A new reaction rate was calculated from the combined results of this work and literature S-factor determinations. Resonance strengths and branchings are reported for several$^{18}$F states. We were able to extrapolate the astrophysical S-factor of the reaction$^{17}$O$(p,\gamma)^{18}$F at low energies from cross section data taken at higher energies. No significant changes in the nucleosynthesis are expected from the newly calculated reaction rate.Comment: Accepted in Physical Review

HOW REPRODUCIBLE ARE THE EFFECTS OF A MICROPROCESSOR FOOT?

Abstract INTRODUCTION Using microprocessor-control to dynamically adapt hydraulic ankles, by changing the resistances to dorsiflexion and plantarflexion (DF/PF) movements, has been shown to have beneficial biomechanical effects during slope descent1. Another, more recent case study also showed that the level walking biomechanical effects of microprocessor-feet (MPF) persist, and the same trends can be observed in repeated gait analysis sessions, over a year apart2. This work looks to expand on both of these concepts, analysing repeated gait analysis sessions to see if the biomechanical changes of MPF during slope descent are reproducible over time. Abstract PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/32013/24432 How to cite: McGrath M, Stech N, Laszczak P, Kercher A, Zahedi S, Moser D. HOW REPRODUCIBLE ARE THE EFFECTS OF A MICROPROCESSOR FOOT? CANADIAN PROSTHETICS & ORTHOTICS JOURNAL, VOLUME 1, ISSUE 2, 2018; ABSTRACT, POSTER PRESENTATION AT THE AOPA’S 101ST NATIONAL ASSEMBLY, SEPT. 26-29, VANCOUVER, CANADA, 2018. DOI: https://doi.org/10.33137/cpoj.v1i2.3201

Future directions and priorities for Arctic bryophyte research

The development of evidence-based international strategies for the conservation and management of Arctic ecosystems in the face of climate change is hindered by critical knowledge gaps in Arctic floristic diversity and evolution. Particularly poorly studied are the bryophytes, which dominant the vegetation across vast areas of the Arctic, and consequently, play an important role in global biogeochemical cycles. Currently, much of what is known about Arctic floristic evolution is based on studies of vascular plants. Bryophytes, however, possess a number of features, such as poikilohydry, totipotency, several reproductive strategies, and the ability to disperse through microscopic diaspores, which may cause their responses to Arctic environments to differ from those of the vascular plants. Here we discuss several priority areas identified in the Arctic Council's ‘Arctic Biodiversity Assessment’ that are necessary to illuminate patterns of Arctic bryophyte evolution and diversity, including dispersal, glacial refugia, local adaptation, and ecological interactions within bryophyte-associated microbiomes. A survey of digitally available herbarium data archived in the largest online aggregate, GBIF, across the Arctic to boreal zones, indicates that sampling coverage of mosses is heterogeneous, and relatively sparse in the Arctic sensu stricostricto. A coordinated international effort across the Arctic will be necessary to address knowledge gaps in Arctic bryophyte diversity and evolution in the context of ongoing climate change

DNA metabarcoding uncovers fungal diversity in soils of protected and non-protected areas on Deception Island, Antarctica

We assessed soil fungal diversity at two sites on Deception Island, South Shetland Islands, Antarctica using DNA metabarcoding analysis. The first site was a relatively undisturbed area, and the second was much more heavily impacted by research and tourism. We detected 346 fungal amplicon sequence variants dominated by the phyla Ascomycota, Basidiomycota, Mortierellomycota and Chytridiomycota. We also detected taxa belonging to the rare phyla Mucoromycota and Rozellomycota, which have been difficult to detect in Antarctica by traditional isolation methods. Cladosporium sp., Pseudogymnoascus roseus, Leotiomycetes sp. 2, Penicillium sp., Mortierella sp. 1, Mortierella sp. 2, Pseudogymnoascus appendiculatus and Pseudogymnoascus sp. were the most dominant fungi. In addition, 440,153 of the total of 1,214,875 reads detected could be classified only at the level of Fungi. In both sampling areas the DNA of opportunistic, phytopathogenic and symbiotic fungi were detected, which might have been introduced by human activities, transported by birds or wind, and/or represent resident fungi not previously reported from Antarctica. Further long-term studies are required to elucidate how biological colonization in the island may be affected by climatic changes and/or other anthropogenic influences

Identity and origin of the <I>Campylopus</I> (Leucobryaceae, Bryopsida) species from Trindade Island (Brazil)

Deux espèces de Campylopus, C. fragiliformis et C. pilifer, ont été reportées sur l’île brésilienne de Trindade, dans l’océan Atlantique Sud, à environ 1 100 km des côtes brésiliennes. Les inférences phylogénétiques basées sur des séquences d’ADN des espaceurs transcrits internes (ITS) de l’unité ribosomique et de trois marqueurs chloroplastidiens sont en accord avec la reconnaissance de deux espèces de Campylopus sur l’île de Trindade. Néanmoins, les populations insulaires de C. pilifer sont imbriquées parmi C. introflexus et celles de C. fragiliformis parmi C. occultus. Le réexamen des caractéristiques morphologiques confirme que les populations de l’île de Trindade appartiennent à ces deux espèces. Sur la base des relations phylogénétiques C. introflexus et C. occultus ont probablement atteint Trindade à partir de l’Amérique du Sud continentale. L’introduction sur Trindade de C. introflexus, en particulier, aurait été favorisée par l’impact humain sévère sur la végétation d’origine durant les cinq derniers siècles.Two species of Campylopus, C. fragiliformis and C. pilifer, were previously reported from Trindade Island, a Brazilian island situated in the South Atlantic Ocean around 1100 km off the coast of mainland Brazil. Phylogenetic inferences from sequences of the nuclear ribosomal internal transcribed spacers and three plastid markers are consistent with the recognition of two Campylopus species on Trindade. However, the island populations of C. pilifer are nested among those of C. introflexus and those of C. fragiliformis among those of C. occultus. A re-investigation of morphological characters confirms that the populations from Trindade Island belong to these species. Based on phylogenetic relationships, both C. introflexus and C. occultus probably reached Trindade from continental South America. The colonization of Trindade by C. introflexus in particular might have been facilitated by the severe human impact on the original vegetation throughout the last five centuries.</p

An updated checklist of the lichens of St. Eustatius, Netherlands Antilles

Volume: 33Start Page: 69End Page: 8

The taxonomic status of intermediate forms of &lt;I&gt;Campylopus introflexus&lt;/I&gt; (Hedw.) Brid. and &lt;I&gt;C. pilifer&lt;/I&gt; Brid. (Dicranaceae, Bryopsida) newly discovered in Europe

Recently mixed stands of Campylopus introflexus (Hedw.) Brid. and another piliferous Campylopus taxon were found in Brittany, France. The latter resembles C. pilifer Brid. by its straight hairpoints, but the lamellae on the dorsal costa surface are only 1-2 cells high, as typical for C. introflexus, instead of 3-4 cells high as characteristic for C. pilifer. Similar plants were recorded before from northern Argentina and the East African islands. Phylogenetic analyses based on sequences of the nuclear ribosomal DNA ITS1 and ITS2 and the chloroplast DNA atpB-rbcL spacer indicate a close relationship of intermediate plants from Brittany and Réunion with C. pilifer accessions from the Old World (Macaronesia, Continental Europe, Arabia). Campylopus introflexus from the same locality in Brittany is part of a well-supported clade of C. introflexus accessions from the subantarctic region, North America and Europe. For practical reasons, the intermediate specimens are distinguished on varietal level, as Campylopus pilifer var. brevirameus (Dix.) J.-P. Frahm &amp; Stech, comb. nov. Campylopus pilifer subsp. pilifer now comprises three varieties with different types of lamellae, var. lamellatus (Mont.) Gradstein &amp; Sipman with six, var. pilifer with three to four, and var. brevirameus with lamellae two cells high. If these expressions represent genotypes or modifications remains to be tested.</p