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Parahyparrhenia khannae A. P. Tiwari & Chorghe 2020
No full text2. Parahyparrhenia khannae A. P. Tiwari & Chorghe (2020: 56). Type:— INDIA, Madhya Pradesh, Ratlam district, Sailana Tahsil, Sailana Bird Sanctuary (Shikarwadi area) 23°25’48.75”N 74°54’44.48”E, 8 October 2015, A. P . Tiwari 75590 (Holotype BSA!; isotypes BLAT! BSA!) Annual, caespitose, 10–30 cm high with shallow root system. Culms very slender, terete, glabrous, purplish at nodes, geniculately ascending; nodes glabrous, darkened. Leaf blades filiform, flat (when young) to involute later, 2.5–6.0 × 1.0– 1.5 mm, glabrous or slightly puberulous above, granulate beneath, margins smooth, sometime with sparse hairs; sheath terete, glabrous, 2.0–3.0 cm long; ligule membranous, lacerated at the apex with ciliae, 0.8–1.0 mm long. Inflorescence a solitary terminal raceme, often in the fascicles of 2–3 pedunculate units, very slender, 2.5–4.5 cm long, subtended by a spatheole, bearing 4–8 fertile spikelets on each; spatheole linear, 3.0–6.0 cm long, herbaceous, glaucous when young, straw coloured when older; rachis flattened, 1.5–2.0 mm long, ciliate on margins (except towards the apex), oblique at tip. Homogamous spikelets 1–2 at the base of a raceme, either barren (almost a scale like appendage) or staminate. Sessile spikelet 4.0–6.0 mm long (incl. callus), very narrow, linear-oblong, awned, falling entire; callus very pungent, protruded, 1.0–2.0 mm long, brownish, vernicose, attached obliquely, bearded with white hairs: lower glume 4.0–5.0 mm long, coriaceous, linear-oblong, with a deep median longitudinal groove on the dorsal surface, obscurely 6-nerved, margins inflexed, scaberulous on dorsal surface in upper half, 2-keeled, bidentate at apex (due to rupturing of a hyaline membrane), darkened on maturity; upper glume 4.0– 4.5 mm long, subcoriaceous, narrowly oblong-lanceolate, glabrous on dorsal surface, obscurely 3-nerved, muticous at apex, margins inflexed, ciliolate in the upper half; lower lemma 2.5–3.0 mm long, epaleate, membranous, elliptic-oblong, dentate and ciliolate apex; upper lemma reduced to a hyaline base of geniculate awn, linear, 3.0– 3.4 mm long, bifid at the apex; awn geniculate 4.5–6.3 cm long, with a long hispidulous cork-screwed column with long hairs; palea absent; lodicules two; stamens 3, anthers 0.5–0.8 mm long. Caryopsis 3.0– 3.5 mm long, purplish, narrowly oblong, glabrous, with a deep median groove on the dorsal surface. Pedicelled spikelet 5.5–6.5 mm long, glabrous; pedicel 1.5–2.0 mm long, ciliate on margins; callus oblong, 0.5–1.0 mm long, acute and straight at the apex, glabrous, with depressions on the ventral side; lower glume 5.5–6.5 mm long, sub-coriaceous, linear-lanceolate, 7-nerved, bi-dentate at the apex (sometimes almost bi-mucronate at the apex), scaberulous on margins; upper glume 5.0– 5.5 mm long, membranous, linear-lanceolate, ciliate on margins, acuminate at apex. Flowering and fruiting:—Flowering and fruiting was observed from September to October. In personal communication with Dr. Mujaffar Shaikh, it was known that the species begins flowering from July and lasts till December. Distribution:— Madhya Pradesh: Burhanpur, Ratlam and Jhabua districts; Gujarat: Rajkot district, Saurashtra, Peninsular India. According to one of the collectors, Dr. Mujaffar Shaikh, this species is seen in a considerable abundance in open grassland in 7 km 2 of area in Asiragarh forest range, Burhanpur district of Madhya Pradesh. A species occurring in such profusion yet remained to be un-described for centuries is fascinating. The species so far appears to be endemic to Central India. Notes:— Parahyparrhenia khannae is a very slender grass with an ascending habit (Fig. 3) and has the shortest stature (ca. 30 cm high) and smallest anther size (i.e. 0.5–0.8 mm long) known in the genus. The racemes are terminal, solitary in 2–3 pedunculate fascicles, extremely narrow with considerably long awns i.e. ca. 6.3 cm long, giving the plant a peculiar appearance at a glance. The obliquely pungent and protruded callus in this species is a very prominent feature which is capable of driving into the finger, if pressed against it. When mature, the lower glume of the sessile spikelet becomes highly coriaceous, darkened and tough, enclosing the caryopsis very tightly. As the lower glume of the sessile spikelet is longitudinally grooved on its dorsal side, it bears a prominent ridge on its ventral surface, which is the cause of the longitudinal depression on the matured caryopsis (Fig. 4, L). The mature hardened spikelets of this species render the task of manually removing the caryopsis, without completely destroying the glume, very formidable. The leaf blades are granulated on their abaxial surface/under-surface; one of the distinguishing features of this species. The raceme and spikelets are much narrower as compared to P. bellariensis. In both the Indian species, lobes of the upper lemma of the sessile spikelet can be best seen during anthesis; later, at maturity, the lobes tend to disintegrate making the lemma appear absolutely entire or undivided like Heteropogon Persoon (1807: 533). So far, this species is known from Madhya Pradesh and Gujarat states. Based on its habitats specificity, it may be predicted that it is likely to occur in dry grasslands of Northern Maharashtra and Chhattisgarh. Specimens examined (paratype):— INDIA: Madhya Pradesh, Jhabua district, Petlawad, Salunea (Kharmor area) 23°55’48.75”N / 74° 48’ 0”E, 10 October 2015, A. P . Tiwari 75595 (BSA!); Gujarat, Rajkot, Saurashtra University 10 October 1977, Bharkava 50 (BSI!). Additional specimens examined:— INDIA: Madhya Pradesh, Burhanpur district, Asirgarh forest range, 11 September 2021, Shaikh Mujaffar SM-1, SM-2, SM-3, SM-4, SM-5, SM-6, SM-7, SM-8, SM-9, SM-10, SM-11, SM-12, SM-13 (BLAT).Published as part of Landge, Shahid Nawaz & Shinde, Rajendra D., 2022, A taxonomic revision of the genus Parahyparrhenia (Poaceae: Andropogoneae) in India and review of African and Thai species, pp. 247-260 in Phytotaxa 541 (3) on pages 255-257, DOI: 10.11646/phytotaxa.541.3.4, http://zenodo.org/record/639262
Capillipedium mistryi A. P. Tiwari & S. N. Landge 2021, sp. nov.
No full textCapillipedium mistryi A. P. Tiwari & S. N. Landge, sp. nov. (Fig. 1 & 2) Type:— INDIA, Madhya Pradesh, Hoshangabad district, Bori Wildlife Sanctuary, Bori Range, 22°15’ to 22° 30’ N lat. and 77°45’ to 78 30’ E long., ca. 500 m elevation, 15 November 2019, A. P . Tiwari 35 (holotype: CAL!; isotype: BLAT!). Diagnosis:— Capillipedium mistryi is closely allied to C. spicigerum in longer racemes, but differs in pedicel and rhachis internode solid, if slightly channeled then not with a translucent groove (vs. with a distinct translucent groove), shorter panicle 4.0–7.0 × 3.0–5.0 cm (vs. 10–25 × 5.0–8.0 cm in the latter), racemes with 11–25 sessile spikelets (vs. racemes with 3–8 sessile spikelets), sessile spikelet 2.5–3.0 mm long (vs. 3.0–4.0 mm long).Published as part of Tiwari, Arjun Prasad & Landge, Shahid Nawaz, 2021, Capillipedium mistryi (Andropogoneae, Poaceae): a new remarkable species from central India, pp. 51-57 in Phytotaxa 498 (1) on page 52, DOI: 10.11646/phytotaxa.498.1.6, http://zenodo.org/record/542409
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Bifunctional Oxygen Electrocatalysis through Chemical Bonding of Transition Metal Chalcogenides on Conductive Carbons
No full textImproving the electrochemical performance of both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) has been of great interest in emerging renewable energy technologies. This study reports an advanced bifunctional hybrid electrocatalyst for both ORR and OER, which is composed of tungsten disulphide (WS2) and carbon nanotube (CNT) connected via tungsten carbide (WC) bonding. WS2 sheets on the surface of CNTs provide catalytic active sites for electrocatalytic activity while the CNTs act as conduction channels and provide a large surface area. Moreover, the newly formed WC crystalline structure provides an easy path for electron transfer by spin coupling and helps to solve stability issues to enable excellent electrocatalytic activity. In addition, it is found that four to five layers of WS2 sheets on the surface of CNTs produce excellent catalytic activity toward both ORR and OER, which is comparable to noble metals (Pt, RuO2, etc.). These findings show the many advantages enabled by designing highly active, durable, and cost-effective ORR and OER electrocatalysts.
© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim6
Activation of Ternary Transition Metal Chalcogenide Basal Planes through Chemical Strain for the Hydrogen Evolution Reaction
No full textCatalytically inactive basal planes pose challenges for the efficient hydrogen evolution reaction (HER) in two-dimensional (2D) transition metal chalcogenide (TMC) nanosheets. Herein, a new hybrid structure is reported in which zero-dimensional TMC nanodots (NDs) are decorated on the basal planes of 2D nanosheets of TMCs to enhance their catalytic activity towards the HER process. A novel process is developed to fabricate a hybrid Cu2MoS4 (2D ternary transition metal chalcogenide Cu2MoS4 nanosheets)/MoSe2 (0D binary transition metal chalcogenide MoSe2 ND) nanostructure by controlling the size of the MoSe2 NDs to enhance the HER activity. In acidic media, this optimal hybrid Cu2MoS4/MoSe2 nanostructure achieves excellent catalytic activity for HER, which exhibits a low overpotential of 166mV at a current density of 10mAcm(-2), which corresponds to a Tafel slope of 74.7mVdec(-1). In addition, the synthesized hybrid nanostructure shows excellent stability when under acidic medium for 16h of continuous electrolysis. Therefore, it is suggested that our strategy may open a new path for the design of hybrid nanostructures by using ternary transition metal chalcogenides (TTMCs) with binary transition metal chalcogenides (BTMCs) for alternative non-noble metal catalysts towards HER.
(c) 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim1331sciescopu
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Full text linkWe 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
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