135,472 research outputs found
Trichoderma bombaxalis Jing Z. Sun & H. W. Liu 2022, sp. nov.
No full textTrichoderma bombaxalis Jing Z. Sun & H.W. Liu, sp. nov. (FIGURE 2) Index Fungorum number: IF559555 Etymology: —“ bombaxalis ” (Latin), bombax+alis, meaning like mature fruits of kapok on culture media. Type: — CHINA. Yinchuan: Ningxia Hui Autonomous Region, 105°97’E, 38°28’N, from rhizosphere soil of Lycium barbarum, 10 May 2021, Jing Z. Sun (HMAS 351590, holotype), ex-type culture CGMCC3.20851. GenBank accessions: ITS = OM109651, OM109652, TEF-1α = OM142599, OM142600, RPB2 = OM142601, OM142601. Description: —On CMD after 72 h, colony diameter 21–25 mm at 25 °C, and 20–37 mm at 30 °C. After 7 days, mycelium loose, a layer of aerial mycelium covering the entire plate at 25 °C and 30 °C (FIGURE. 2C, G). Many conidiophores formed by 5 days, unknown aromatic odour, and no pigment. On PDA after 72 h, colony diameter 6–7 mm at 25 °C, and 4–5 mm at 30 °C. At 25 °C, white colony, cotton-like, dense hyphae. At 30 ℃, white flocculent colony, uniform mycelial density, coconut aroma, and no pigment. After 7 days, colony diameter 13–14 mm at 25 °C (FIGURE 2A), and 9–10 mm at 30 °C, not producing concentric rings or radial rays of mycelium (FIGURE 2E). On SNA after 72 h, colony diameter 15–22 mm at 25 °C, and 17–21 mm at 30 °C. White colony, mycelium loose, light coconut aroma. After 7 days, colony edge was irregular, and mycelium was loose, coconut aroma and no pigment (FIGURE 2B, F). Conidial production noted after 5 days. Conidiophores branched verticillium-like, phialides subulate, variable in length, in whorls or opposite, 2–3(–4) branches, (8.8–)11–18(–23.2) × (1.3–)2.0–3.0(–3.4) μm (x = 14.3 × 2.4 μm, n = 20) (FIGURE 2D, H, I, J). Conidia obovate to ellipsoidal, roughened (FIGURE 2K, L), (2.0–)2.5–3.6(–4.5) × (1.0–)1.4–2.0(–2.4) µm (x = 3.1 × 1.7 µm, n = 50), length/width ratio (1.2–)1.5–1.8 (–2.4) (x = 1.6, n = 50). No sexual morphogenesis. Additional specimen examined: — CHINA. Yinchuan: Ningxia Hui Autonomous Region, 105°97’E, 38°28’N, from rhizosphere soil of Lycium barbarum, 10 May 2021, Jing Z. Sun (HMAS 351591), culture CGMCC3.20852. Teleomorph: —Undetermined. Notes: — Trichoderma bombaxalis differs from other species in section Hypocreanum (T. austriacum, T. eucorticioides, T. sulphureum, T. subsulphureum, T. avictoriense) in the size of phialides and conidia (TABLE 2). Ability to degrade cellulose and hemicellulose Trichoderma bombaxalis was inoculated on xylan medium and CMC-Na medium for 7 days (FIGURE 3). Transparent zones were present around the colony on CMC-Na medium following Congo red dyeing and decolouration (FIGURE 3D), indicating a capacity to hydrolyze cellulose. However, no transparent zones were observed on the xylan medium, indicating weak or no ability to use hemicellulose. Trichoderma bombaxalis may be a potential candidate for cellulase exploration.Published as part of Yu, Shuang, Wang, Rui, Liu, Hong-Wei, Zhang, Xue & Sun, Jing-Zu, 2022, Trichoderma bombaxalis sp. nov., isolated from rhizosphere soils of Lycium barbarum, pp. 147-157 in Phytotaxa 547 (2) on pages 152-155, DOI: 10.11646/phytotaxa.547.2.2, http://zenodo.org/record/657141
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
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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
The construction of Karen Karnak: The multi-author-function
No full textThis thesis is situated within the comparatively recent developments of Web 2.0 and the emergence of interactive WikiMedia, and explores the mode of authorship within a Read/Write culture compared to that of a Read/Only tradition. The hypothesis of this study is that the role of the audience has become merged with the author, and as such, represents new functions and attributes, distinct from a more conventional concept of authorship, in which the roles of audience and author are more separate. Read/Write and participatory culture, as defined by this study, is focused on collaboration, and includes the influences of D.I.Y. culture, Open-Source practices and the production of text by multiple authors. Multi-authorship presents a re-thinking of several concepts which support the notion of the individual author, since the focus of multi-authorship is not on attribution and ownership of a finished text, but on the continued malleability of a text. Modes of multi-authorship, demonstrated in the use of the pseudonyms Alan Smithee and Karen Eliot, represent declarative authors whose names signify multiple origins, whilst concurrently indicating a distinct body of work. The function of these names form an important context to this study, since primary research involves the construction of an experimental mode of multi-authorship utilising WikiMedia technology and the interaction of thirty nine participants, who are invited to create a body of work under the collective pseudonym Karen Karnak. The data generated by this experiment is analysed using aspects of Michel Foucault's author-function to identify and determine power structures inherent in the WikiMedia context. The interplay of power structures, including concepts such as identity, ownership and the body of work, affect the resulting mode of authorship and contribute to the construction of Karen Karnak, suggesting further areas of research into the emerging multi-author
Contribution of Information and Communication Technology (ICT) in Country’S H-Index
No full textThe aim of this study is to examine the effect of Information and Communication Technology (ICT) development on country’s scientific ranking as measured by H-index. Moreover, this study applies ICT development sub-indices including ICT Use, ICT Access and ICT skill to find the distinct effect of these sub-indices on country’s H-index. To this purpose, required data for the panel of 14 Middle East countries over the period 1995 to 2009 is collected. Findings of the current study show that ICT development increases the H-index of the sample countries. The results also indicate that ICT Use and ICT Skill sub-indices positively contribute to higher H-index but the effect of ICT access on country’s H-index is not clear
Expression and characterization of E-LecEGF for structural study and assay development
No full textHuman E-selectin (hE-selectin) is a cell adhesion molecule expressed on the membrane of endothelial cells. It is a C-type lectin whose key role is to mediate the initial rolling and adhering of leukocytes in the leukocyte recruitment in inflammation and metastasis of some cancer cells. It is fundamentally involved in many physiological and pathological processes, and hence is an attractive target for developing anti-inflammation drugs. The lectin and EGF domains of hE-selectin (hE-LecEGF) were identified as the minimum functional unit. Crystal structures of hE-LecEGF complexed with its natural ligand, tetrasaccharide sialyl Lewisx (sLex), as well as NMR studies of hE-selectin/IgG bound with this ligand, have been reported and utilized as the structural basis for the development of potent antagonists for hE-selectin. More potent antagonists with better binding affinity than sLex, such as CGP69669, were reported, but their binding modes in hE-LecEGF remain unknown. To obtain the improved structural information of hE-LecEGF complexed with an antagonist and develop more potent antagonists of hE-selectin are challenging tasks. To meet the demands of the protein for the structure determination and the binding assay, a sufficient amount of pure and active hE-LecEGF is needed. In this thesis, insect cell expression systems were initially used to produce the hE-LecEGF protein. hE-LecEGF was cloned, transiently expressed and characterized in Sf9 and High fiveTM cells. The expression plasmid pFastBacYJSE was constructed for expression of the hE-LecEGF protein fused with a N-terminal Flag tag. The recombinant baculovirus was generated and used in the expression of protein in the suspension culture. Pure hE-LecEGF was obtained by anti-Flag M2 affinity chromatography under the optimized condition. The purified protein was active and glycosylated, as identified by mAb 7A9 and glycan detection, respectively. Unfortunately, the homogeneous hE-LecEGF protein was not obtained after the deglycosylation with PNGase F and N-glycosidase A. hE-LecEGF was then cloned, stably expressed and characterized in CHO K1 cells. Stable subclones CHO-YJES and CHO-YJEGS expressing the hE-LecEGF protein with or without a human IgG1 tag were achieved. The CHO-YJES construct was used for production. The monoclonal anti-E-selectin functional blocking antibody 7A9 (mAb 7A9) was produced, purified and coupled to sepharose for functional purification of the hE-LecEGF protein. Highly pure hE-LecEGF protein was obtained in a one-step purification with an mAb 7A9 coupled column. Page, western-blotting, ELISA, MS and NMR were performed to characterize the hE-LecEGF protein. Pure, monomeric and active hE-LecEGF with the molecular weight of 20.444 kDa was obtained. In contrast to the insect cell expression system, pure, active and
uniform deglycosylated hE-LecEGF protein was obtained after treatment with PNGase F and purification by a Sepharose Q matrix. A prescreening of the crystallization condition of hE-LecEGF was also performed using a sitting-drop method. Furthermore, a novel cell-free assay “capture-binding assay” was developed with the tag-free hE-LecEGF protein to evaluate the binding activity of the hE-LecEGF protein and the binding affinity of hE-selectin antagonists. The rIC50 of six hE-selectin antagonists was determined. The obtained results were in close agreement with the published results. Compared to the previously unstable polymer assay with hE-selectin/IgG, the capture-binding assay with hE-LecEGF is accurate, sensitive and reproducible. It can correctly evaluate the binding affinities of hE-selectin antagonists. In addition, the antibody BBA1 was used to solve the problem of immobilization of the hE-LecEGF protein on ELISA plates in the assay
Output-feedback-based H∞ control for vehicle suspension systems with control delay
No full textThis paper deals with the problem of output-feedback H∞ control for a class of active quarter-car suspension systems with control delay. The dynamic system of the suspension systems is first formed in terms of the control objectives, i.e., ride comfort, road holding, suspension deflection, and maximum actuator control force. Then, the objective is to the design of the dynamic output-feedback H∞ controller in order to ensure asymptotic stability of the closed-loop system with H∞ disturbance attenuation level and the output constraints. Furthermore, using Lyapnov theory and linear matrix inequality (LMI) approach, the existence of admissible controllers is formulated in terms of LMIs. With these satisfied conditions, a desired dynamic output-feedback controller can be readily constructed. Finally, a quarter-vehicle model is exploited to demonstrate the effectiveness of the proposed method. © 1982-2012 IEEE
Fully Turbulent Mean Velocity Profile for Purely Viscous non-Newtonian Fluids
No full textThe characteristic near wall behavior of turbulent flow of purely-viscous non-Newtonian fluids is discussed for both power-law (P.-L.) and Herschel-Bulkley (H.-B.) rheological models. A proper scaling is presented for H.-B. fluids to establish an analogy with power-law fluids with same flow index. To provide reference data for turbulent flow of non-Newtonian fluids, DNS simulations of power-law fluids are conducted in a rectangular channel for a large range of power-law indices ( = 0.5, 0.69, 0.75, 0.9, 1, 1.2). The DNS data show that the mean velocity profile in the viscous and logarithmic layers follow expressions of the form and respectively, where shows a logarithmic dependency on the flow index.Comparison with some experimental data shows the above formulation to be valid for Reynolds numbers (based on shear velocity) as high as 1000
H-index and research evaluation: A suggested set of components for developing a comprehensive author-level index
No full textThe H-index has been investigated in various studies; this index has many strengths that have made it popular. However, it also has weaknesses, due to which other indicators have been developed. This study aims to identify the strengths and weaknesses of the H-index and provide the minimum set of necessary components for developing a comprehensive author-level index. In this systematic literature review, Scopus, PubMed, Web of Science, Emerald, and ProQuest databases were searched to identify relevant studies. From the number of 14,253 retrieved studies, after two stages of screening, 81 studies were selected according to the eligibility criteria for data extraction. The findings of the study led to the identification of 15 strengths in the three categories of Quality Features, Simplicity, and Suitability, and 13 weaknesses in the six categories of Publications, Citations, Academic Age, Author Credit Allocation, Variety of Fields, and mathematical calculation for H-index. Finally, 28 components were identified as the minimum set of necessary components to develop a comprehensive author-level index to help evaluate researchers more realistically and fairly. The minimum components that need to be considered in developing a comprehensive author-level index can be proposed as follows: Quality Features, Simplicity, Suitability, Publications, Citations, Academic Age, Author Credit Allocation, Variety of Fields, and mathematical calculation
- …
