130,822 research outputs found
Diacheopsis cinerea A. Vlasenko & V. Vlasenko 2022, sp. nov.
No full textDiacheopsis cinerea A. Vlasenko & V. Vlasenko, sp. nov. (Figs 1A–E, 2A–J) Index Fungorum number: IF557664; Facesoffungi number: FoF 08147 Sporocarps sessile, cylindrical, about 0.7–0.9 mm in diam. and 0.9–1.1 mm in total height, gregarious, scattered or in small groups of 2–8, drab grey, beige, densely clustered. Peridium single, membranous, translucent below, more dense at the top, fugacious above, persisting as a deep cup at the base; transparent, very light, with a slight greyish colour (in transmitted light) in the lower and lateral parts of the sporocarps; in the apex of sporotheca it is light-ocher, transparent (in transmitted light); it is often common in adjacent sporocarps, but with preservation of the side walls between adjacent sporocarps. Dehiscence is apical irregular. After the complete destruction of sporocarps, basal rings remain attached to the substrate. Columella absent. Capillitium dark violet-brown, with expanded nodes of dark brown colour, branched and anastomosed, arising from the base and forming a network connected to the peridium and the base of sporotheca by paler tips. Hypothallus continuous under the group (confluent), thin, light-coloured. Spore-mass dark brown to dark. Spores globose, 10.5–13.0 µm diam. including ornamentation, densely and uniformly covered by warts up to 0.4 µm in total height. In SEM, the ornamentation appears as dense, abundant and regularly distributed, well-developed, coralloid projections on the apex of each wart. Plasmodium not seen. Etymology:— Referring to the colour of sporocarps. Type:— RUSSIA. Altai Territory: near Losikha railway station, dry pine forest, on a fallen tree of Pinus sylvestris, 8 July 2009, leg. A. Vlasenko and V. Vlasenko, NSK 1030140 (holotype), GenBank SSU: MT 386336. Additional specimen examined:— RUSSIA. Altai Territory: near Losikha railway station, pine forest, on dead wood of Pinus sylvestris, 26 August 2019, leg. A. Vlasenko and V. Vlasenko, NSK 1030138 (paratype). Ecology:— Xylobiont. Distribution:— Known only from type locality. Comments:— Phylogenetically, Diacheopsis cinerea grouped with Lamproderma echinosporum and L. gulielmae. We have received data that other species of Diacheopsis are phylogenetically similar to those of the genus Lamproderma (Fig. 3). Diacheopsis metallica is closest to L. cristatum, while D. pauxilla is closest to L. sauteri and L. ovoideoechinulatum. Similar to Lamproderma, the morphological genus Diacheopsis consists of several separate phylogenetic lines. At the same time, the species that represent different phylogenetic lines demonstrate morphological similarities. Classification of the family Stemonitidaceae is not developed and is based on morphological features. Based on a complex of morphological features, we assigned the new species to the genus Diacheopsis. Diacheopsis cinerea has a warty ornamentation of spores, which brings it close to the group of species that have spores with warts: D. laxifila, D. minuta, D. mitchellii, D. pieninica, D. rigidifila, D. vermicularis, D. griseobrunnea and D. serpula. Spores of D. mithellii are very large, 20–21 µm in diam., covered with long spines or warted, about 1 mm in length and with tips that appear frayed under SEM. In comparison, the spores of D. cinerea are significantly smaller, 10.5–13.0 µm in diam., densely and uniformly covered with warts that are up to 0.4 µm in total height. By SEM, their ornamentation consists of dense, abundant, regularly distributed and well-developed coralloid projections on the apex of each wart. Spores of D. pieninica, D. rigidifila, and D. griseobrunnea are less than 9 µm in diam. (spores of D. cinerea are larger than 10 µm in diam.). Spores of D. laxifila are united into clusters while spores of D. cinerea are free. Sporocarps of D. minuta are very small, 0.2–0.4 mm in total height, of bronze colour while sporocarps of D. cinerea are 2–3 mm in total height, and grey-beige in colour. In D. serpula, elongated plasmodiocarps are predominant in the colony but in D. cinerea, sessile sporangia are predominant. Capillitium of D. serpula is without extensions while that of D. cinerea is with numerous filmy brown extensions. Capillitial nodes of D. vermicularis are rounded but in D. cinerea they are triangular and quadrilateral. The capillitial threads of D. vermicularis are colorless or grey and in D. cinerea they are dark violet-brown, and only the ends of threads by which they are attached to the base of sporocarp and peridium are light. The spores of D. vermicularis are light brown, with dark areas consisting of groups of warts (in transmitted light); those of D. cinerea are brown, and evenly ornamented with warts. In shape and size of sporocarps, the new species resembles D. insessa and D. nannengae, but it differs significantly by the structure of capillitium, size of the spores and their ornamentation. Spores of D. insessa are 16–22 µm in diam. and ornamented with long spines while the spores of D. cinerea are less than 14 µm in diam., and ornamented by warts. Spores of D. nannengae are ornamented with short spines while spores of D. cinerea have long warts up to 0.4 µm in total height. The capillitium of D. nannengae arises only from the base of sporotheca but in D. cinerea it arises from the base and forms a network connected by paler tips to the peridium and the base of sporotheca. Samples of D. cinerea were first found by us in 2009 in dry pine forests in the northern part of the “Verkhneobsky pine forest”, located on the right bank of Priobsky Plateau. Diacheopsis cinerea was collected there again 10 years later, which indicates the existence of a stable community of the species. The fructification of the species was observed after prolonged rains.Published as part of Vlasenko, Anastasia V., Vlasenko, Vyacheslav A. & Kabilov, Marsel R., 2022, A new species of Diacheopsis from Russia, pp. 193-200 in Phytotaxa 541 (2) on pages 195-199, DOI: 10.11646/phytotaxa.541.2.9, http://zenodo.org/record/638879
FIGURE 2 in A new species of Tulostoma genus from Siberia
No full textFIGURE 2. Мicromorphological characters of Tulostoma morenoi (holotype). (a, c) Spores, capillitial threads (SEM). (b) Spores (SEM). (d) Spore warts with ridge-like anastomoses (SEM). (e) Spore, spore warts (SEM). Scale bars: a—30 μm, b, c, e—2 μm, d—1 μm.Published as part of Vlasenko, Vyacheslav A. & Vlasenko, Anastasia V., 2023, A new species of Tulostoma genus from Siberia, pp. 25-34 in Phytotaxa 600 (1) on page 29, DOI: 10.11646/phytotaxa.600.1.4, http://zenodo.org/record/805416
FIGURE 1 in A new species of Diacheopsis from Russia
No full textFIGURE 1. Diacheopsis cinerea (holotype). A–D. Sporocarps (DM). E. Basal rings (DM). Scale bars: A–D = 1 mm, E = 2 mm.Published as part of Vlasenko, Anastasia V., Vlasenko, Vyacheslav A. & Kabilov, Marsel R., 2022, A new species of Diacheopsis from Russia, pp. 193-200 in Phytotaxa 541 (2) on page 196, DOI: 10.11646/phytotaxa.541.2.9, http://zenodo.org/record/638879
FIGURE 2 in Stemonitis amphorocolumella (Stemonitidaceae, Myxomycetes), a new species from Western Siberia
No full textFIGURE 2. Stemonitis amphorocolumella (Holotype). A.—Columella and capillitum (SEM). B.—Spore (SEM). C.—Collar at the base of the sporotheca (SEM). D.—Collar at the base of the sporotheca (SEM). Scale bars: A = 100 µm, B = 15 µm, C–D = 100 μm.Published as part of Vlasenko, Anastasia V., Moreno, Gabriel H. & Vlasenko, Vyacheslav A., 2023, Stemonitis amphorocolumella (Stemonitidaceae, Myxomycetes), a new species from Western Siberia, pp. 59-67 in Phytotaxa 592 (1) on page 63, DOI: 10.11646/phytotaxa.592.1.5, http://zenodo.org/record/783567
FIGURE 1 in Stemonitis amphorocolumella (Stemonitidaceae, Myxomycetes), a new species from Western Siberia
No full textFIGURE 1. Stemonitis amphorocolumella (Holotype). A.—Sporocarps. B.—Columella and capillitum (transmitted light). C.—Apex of columella (transmitted light). D.—Apex of columella (transmitted light). E—Apex of columella (transmitted light). F.—Collar at the base of the sporotheca (transmitted light). G.—Collar at the base of the sporotheca (transmitted light). H.—Lower part of the stalk (transmitted light). Scale bars: A = 1 mm, B = 80 µm, C–H = 100 μm.Published as part of Vlasenko, Anastasia V., Moreno, Gabriel H. & Vlasenko, Vyacheslav A., 2023, Stemonitis amphorocolumella (Stemonitidaceae, Myxomycetes), a new species from Western Siberia, pp. 59-67 in Phytotaxa 592 (1) on page 62, DOI: 10.11646/phytotaxa.592.1.5, http://zenodo.org/record/783567
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
