131,104 research outputs found
In Vitro Propagation of Clausena lenis Drake
No full textClausena lenis Drake, a valuable medicinal plant in the Rutaceae family, faces threats from wildlife predation, overharvesting, and climate change. In the wild, C. lenis primarily propagates through seeds; however, their rapid loss of viability poses challenges for long-term storage and germplasm conservation. Plant tissue culture offers a practical solution for both its conservation and large-scale production. This study examines seed sterilization, callus induction, shoot multiplication, and root induction protocols for C. lenis. Seeds attained a 100% sterilization rate using 0.2% (w/v) HgCl2 for 20 min without compromising germination. When cultured on MS medium containing 0.5 mg/L 2,4-D, seed, stem-node, and 1-week-old seedling explants produced abundant callus. A 2.0 mg/L BA treatment achieved 100% shoot induction, with stem-node explants yielding the highest shoot proliferation (3.90 ± 0.31 shoots/explant), followed by 1-week-old seedlings (2.30 ± 0.21 shoots/explant) and seed explants (1.60 ± 0.16 shoots/explant). Rooting was most effective on half-strength MS medium supplemented with 20.0 mg/L IBA, producing an average of 4.30 ± 0.83 roots per shoot in shoot-tip-deprived explants. The rooted plantlets successfully acclimatized, attaining a 100% survival rate in a 1:1:1 mixture of sterile soil, cocopeat, and vermiculite. These findings provide a robust platform for the sustainable propagation and conservation of C. lenis in response to its growing vulnerabilities
Another fortis-lenis language : A reanalysis of Old English obstruents
No full textThe theoretical framework adopted in the analysis of Old English obstruents is laryngeal realism, a framework using privative features in modelling laryngeal oppositions. Equipollent oppositions, although real in the phonetic sense, must clearly be delineated from phonology. Old English obstruents are either unmarked (lenis/neutral) or marked: 〈b〉 /b/, 〈d〉 /d/, 〈cg〉 /dʒ/ or /ɟ/, 〈g〉 /ɡ/ are not marked for [voice] (although they are passively voiced between sonorants) and as such cannot regressively voice obstruents, singleton 〈p〉 /p/, 〈t〉 /t/, 〈ć〉 /tʃ/ or /c/, 〈c〉 /k/ are marked for [spread] (aspiration, or GW ‘glottal width’), singleton 〈f〉, 〈þ/ð〉, 〈s〉, 〈g〉, 〈h〉 are unmarked, but are passively voiced in the FricV/Son environment. Fricatives in unstressed syllables (even when couched between sonorants) are not voiced. If there is a sonorant separating the fricative from the stressed vowel there is no voicing ( SonFricV/Son). The only voiced fricatives after a stressed vowel+sonorant consonant are /f/ [v] and /x/ [ɣ] (but this is a historical coincidence). (Phonetically voiceless) Geminates, s+stop and f/h+stop clusters are special in that they constitute a sequence of a fortis followed by a lenis obstruent impervious to passive voicing
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
Danish stop consonants: Perception, voicing, fortis-lenis and transcription
No full textDet centrale tema i den debat om lydskriften af dansk der nyligt har fundet vej til Nydanske Sprogstudier og Danske Studier, kan indkredses til et spørgsmål om hvorvidt og i hvilket omfang valget af lydskriftsymboler kan og skal overholde principperne i The Handbook of the International Phonetic Association. Debatten suppleres her med en nærmere omtale af tre væsentlige forhold. (i) Dansk (b d ɡ) er inhærent ustemte, men lyder ikke som (p t k) i andre sprog. (ii) Den fraværende stemthed kan tydeliggøres med et diakritisk tegn, [◌̥ ] eller [◌̊ ], altså [b̥ d̥ ɡ̊ ], eftersom tegnet ikke kun bruges om inhærent stemte lukkelyde der afstemmes af de lydlige omgivelser, men også for lyde der er inhærent ustemte. (iii) Forskning internationalt dokumenterer at artikulationsstyrke (fortis og lenis) har artikulatoriske og akustiske korrelater som så vidt vides undtagelsesløst ledsager stemthedsforskelle i lukkelyde og hæmmelyde, men ikke vice-versa – eftersom fortis-lenis forskellen kan optræde uden ledsagende stemthedsforskel. Det betyder at [p t k] i IPA’s lydskriftalfabet de facto ikke bare identificerer ustemte, men også fortes lukkelyde. Sammen med konstateringen af den auditive forskel gør det /p t k/ hhv. [p t k] uegnede som fonemskrift hhv. lydskrift af lukkelydene i fx bille, dille, gilde.The central theme in the recent debate in Nydanske Sprogstudier and Danske Studier about the transcription of Danish can be narrowed down to whether and to what extent the choice of phonetic symbols could and should comply with the principles of The Handbook of the International Phonetic Association. The debate is supplemented here with a closer look at three pertinent topics. (i) Danish (b d ɡ) are inherently voiceless, but do not sound like (p t k) in other languages. (ii) The absence of voicing can be made explicit with a diacritic, [◌̥], i.e. [b̥ d̥ ɡ̊ ], since it is not restricted to devoicing by the phonetic context but employed also for inherently unvoiced sounds. (iii) Research internationally shows that articulatory strength has articulatory and acoustic correlates that seem to invariably accompany voicing differences in obstruents, but not vice-versa – since differences in fortis-lenis may exist without accompanying voicing differences. The implication is that [p t k] in the IPA de facto identifies not only voiceless, but also fortes consonants. Together with the auditory difference it makes /p t k/ and [p t k] unsuitable as representations of the initial stops in e.g. bille, dille, gilde ’beetle, craze, party.
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
Asset versus consumption poverty and poverty dynamics in the presence of multiple equilibria in rural Ethiopia
No full textEffective poverty reduction programs require careful measurement of poverty status. Several studies have shown conceptually that assets reflecting productive capacity form a more robust basis for identifying the poor than do flow variables such as expenditures or income. Nonetheless, little work has empirically compared poverty measurements based on assets and expenditures. This paper uses panel data from Ethiopia to generate an asset-based poverty classification scheme. Regression results are used to estimate an asset index and classify households into categories of structural poverty. Asset index dynamics are also explored to test for the existence of multiple asset index equilibria; evidence of potential poverty traps. Results provide evidence of multiple equilibria in the study sample as a whole as well as convergence at different levels over space, depending on commercialization opportunities and agroecological factors. The asset-based poverty classifications consistently predict future poverty status more accurately than do income-based measures, confirming that the asset-based measure could be used to more carefully target poverty interventions in rural areas and to more accurately assess the impact of those interventions.asset index, asset poverty, Commercialization, expenditures, income-based measures, index equilibria, Poverty dynamics, Poverty reduction, regression,
Impact of Irpex lenis and Schizophyllum commune endophytic fungi on Perilla frutescens: enhancing nutritional uptake, phytochemicals, and antioxidant potential
No full textBackground: Endophytic fungi (EF) reside within plants without causing harm and provide benefits such as enhancing nutrients and producing bioactive compounds, which improve the medicinal properties of host plants. Selecting plants with established medicinal properties for studying EF is important, as it allows a deeper understanding of their influence. Therefore, the study aimed to investigate the impact of EF after inoculating the medicinal plant Perilla frutescens, specifically focusing on their role in enhancing medicinal properties. Results: In the current study, the impact of two EF i.e., Irpex lenis and Schizophyllum commune isolated from A. bracteosa was observed on plant Perilla frutescens leaves after inoculation. Plants were divided into four groups i.e., group A: the control group, group B: inoculated with I. lenis; group C: inoculated with S. commune and group D: inoculated with both the EF. Inoculation impact of I. lenis showed an increase in the concentration of chlorophyll a (5.32 mg/g), chlorophyll b (4.46 mg/g), total chlorophyll content (9.78 mg/g), protein (68.517 ± 0.77 mg/g), carbohydrates (137.886 ± 13.71 mg/g), and crude fiber (3.333 ± 0.37%). Furthermore, the plants inoculated with I. lenis showed the highest concentrations of P (14605 mg/kg), Mg (4964.320 mg/kg), Ca (27389.400 mg/kg), and Mn (86.883 mg/kg). The results of the phytochemical analysis also indicated an increased content of total flavonoids (2.347 mg/g), phenols (3.086 mg/g), tannins (3.902 mg/g), and alkaloids (1.037 mg/g) in the leaf extract of P. frutescens inoculated with I. lenis. Thus, overall the best results of inoculation were observed in Group B i.e. inoculated with I. lenis. GC-MS analysis of methanol leaf extract showed ten bioactive constituents, including 9-Octadecenoic acid (Z)-, methyl ester, and hexadecanoic acid, methyl ester as major constituents found in all the groups of P. frutescens leaves. The phenol (gallic acid) and flavonoids (rutin, kaempferol, and quercetin) were also observed to increase after inoculation by HPTLC analysis. The enhancement in the phytochemical content was co-related with improved anti-oxidant potential which was analyzed by DPPH (% Inhibition: 83.45 µg/ml) and FRAP (2.980 µM Fe (II) equivalent) assay as compared with the control group. Conclusion: Inoculation with I. lenis significantly enhances the uptake of nutritional constituents, phytochemicals, and antioxidant properties in P. frutescens, suggesting its potential to boost the therapeutic properties of host plants. Graphical Abstract: (Figure presented.)Microbial Cell Factorie
"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
- …
