109,048 research outputs found
Corporate governance and financial performance: an emerging economy perspective
No full textThis paper investigates the influence of firm-level corporate governance on financial performance of the listed firms in Bangladesh. Agency theory suggests that better corporate governance reduces expropriation costs, which, in turn, enhances investors’ confidence in the firm’s future cash flow and growth prospects, leading to higher firm valuation. Likewise, a decrease in private benefits is likely to cause an improved operating performance. This paper uses a questionnaire survey-based corporate governance index (CGI), comprising of the three dimensions – shareholder rights, independence and responsibilities of the board and management, and financial reporting and disclosures. The study results partly confirm the prediction of the agency theory, with a statistically significant positive relationship between a firm’s corporate governance quality and its valuation, even though the relationship between firm level corporate governance and operating performance seems inconclusive
Gonadotropin-inhibitory hormone (GnIH) in the amphibian brain and its relationship with the gonadotropin releasing hormone (GnRH) system: An overview
No full textIt is well known that the hypothalamic neuropeptide gonadotropin-releasing hormone (GnRH) plays an important role as a primary factor regulating gonadotropin secretion in reproductive processes in vertebrates. The discovery of the presence of a gonadotropin-inhibitory hormone (GnIH) in the brains of birds has further contributed to our understanding of the reproduction control by the brain. GnIH plays a key role in inhibition of reproduction and acts on the pituitary gland and GnRH neurons via a novel G protein-coupled receptor (GPR147). GnIH decreases gonadotropin synthesis and release, thus inhibiting gonadal development and maintenance. The GnRH and GnIH neuronal peptidergic systems are well reported in mammals and birds, but limited information is available regarding their presence and localization in the brains of other vertebrate species, such as reptiles, amphibians and fishes. The aim of this review is to compile and update information on the localization of GnRH and GnIH neuronal systems, with a particular focus on amphibians, summarizing the neuroanatomical distribution of GnIH and GnRH and emphasizing the discovery of GnIH based on RFamide peptides and GnIH orthologous peptides found in other vertebrates and their functional significance
Cell scientist to watch – Arun Shukla
No full textABSTRACT
Arun Shukla received his master’s degree in Biotechnology from the Jawaharlal Nehru University in New Delhi, and joined the lab of Nobel laureate Hartmut Michel at the Max Planck Institute of Biophysics in Frankfurt, Germany, for his PhD. He then moved to the United States for his postdoctoral work with Robert Lefkowitz at Duke University (Durham, NC) in a very close collaboration with Brian Kobilka (Stanford University, CA). Arun became an Assistant Professor in the Department of Medicine at Duke University in 2011, before returning to India in April 2014 as an Assistant Professor at the Indian Institute of Technology (IIT) in Kanpur as a Wellcome Trust DBT India Alliance Intermediate Fellow. His research is centred on G-protein-coupled receptors (GPCRs), and he applies molecular, cellular and structural biology methods to understand the signalling and activation pathways of GPCRs.</jats:p
Localization of molluscan cardioexcitatory tetrapeptide in the brain of African Cichlid fish (Haplochromis burtoni) revealed by immunocytochemistry
No full textThe FMRFamide-like immunoreactivity was investigated in the brain of African cichlid fish, Haplochromis burtoni, in which sexual maturation is under social control. In both dominant and subdominant males and females, the FMRFamide immunoreactive (ir) cells were found only in tl ie nucleus olfacto-retinalis and in the nucleus of the midbrain tegmentum, However, several FMRFamide-ir fibers were seen in the olfactory bulb and throughout the entire brain of both male morphs and female fish. As the role of nucleus olfacto-retinalis is well known in chemoreception, these results suggest the involvement of FMFRamide-like peptide in the chemosensory control of reproductive behavior in this species. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved
Licneremaeus indicus Arun & Ramani 2020, sp. nov.
No full textLicneremaeus indicus sp. nov. (Figs. 14–28) Diagnosis. Rostral tectum without areolae. Sensillus discoidal with fine barbs. Notogaster with elevations or bumps. At most 14 areolae present on the notogaster in dorsal view. Thirteen pairs of notogastral setae present. Porose areae Aa and A 2 present. Pygidium at the posterior end of notogaster. Epimeral setation: 2-1-3-1. Ventral plate fully areolate. Measurements. Body length 101 (holotype), 98–103 (15 paratypes); body width 59 (holotype), 58–62 (15 paratypes). Integument. Cuticle greyish brown in color. Body covered with abundant cerotegument in the form of small rounded granules. Microareolar patterns seen on notogaster, other than the 14 areolae. Prodorsum (Figs. 14, 20–21, 23). Rostrum pointed apically. Lamellar (le, 8), rostral (ro, 10) and interlamellar (in, 8) setae simple, covered with granules/cerotegument and slightly curved. Length of setae le and ro shorter than the distance between the bases of their counterparts. Seta in inserted near to dorsosejugal suture, below the level of anterior tip of the notogaster. Bothridial cup widely open at the postero-lateral borders of prodorsum, sensillus (ss, 18), with clavate head and a short stalk, bearing thick, blunt spines. Transverse hump present in front of anterior most tip of dorsosejugal suture. Prodorsal surface bears chitinous lines. Seta le arises from the transverse ridge joining, two strong chitinous lines. Pedotectum I present, pedotectum II absent. Notogaster (Figs. 14, 20, 22, 24). Dorsosejugal suture highly convex, extending beyond interlamellar region and incomplete, being interrupted medially, towards the anteriormost portion. Notogaster cuneate anteriorly and oval posteriorly. Thirteen pairs of small, smooth, slightly curved setae present on notogaster, often covered with cerotegument giving a leaf like appearance. Setal length vary from 4–8 as the following; c 3, da (4); c 1, dm, dp, la (5); p 1, p 2, h 1, h 2, h 3 (6); lm (7); lp (8); c 2 and p 3 absent. Lyrifissures im, ip and ips present, im more or less horizontally placed between lm and lp; ip and ips visible in ventral view. Porose area Aa present closer to seta la; A 2 located posteriorly, above the level of seta h 2. An array of cuticular elevations and bumps present on notogaster. The first bump located at the region between setae da and c 1, surrounding an areolae; the second bump central in position, located between setae da and dm and it extends laterally on either sides, towards seta lm; the third bump located below the second one, curved and U-shaped, extending posteriorly, to slightly below the level of seta dp, encompassing an areolae. It extends laterally also on either side, as a transverse bump towards the insertion of seta lp. Three areolae present, between the field delimited by the bases of dm, la and lm. Apart from the above three areolae encompassed by the bumps, a single areola detected anteromedially on the notogaster, between setae c 1, of either side. Posterior border of notogaster produced in to a pygidium. Gnathosoma (Figs. 15, 25). Chelicera (20) with small fixed and movable digits, seta cha (8) small and smooth, chb inconspicuous. Cheliceral teeth feebly developed. Trägardh’s organ (Tg) narrowly triangular. Mentum and submentum with wrinkles. Subcapitular setae h (5), m (6), a (4), or (2) smooth. Rutellum with three weakly developed dendrites. Palpal (24) surface striated. Coxisternal region (Figs. 15, 26). With six pairs of short, smooth, and tapered epimeral setae (1a, 1b, 2a, 3a, 3b, and 4b), of approximately equal length. Epimeral setal formula 2-1-2-1 (4a absent). Epimeres I and II fused together and epimeres III and IV fused together and the fused epimeres delimited by apodemes. Coxisternal area margined by wrinkled ridges. Median depression seen on the fused epimeral plates, I and II as well as III and IV. Ventral plate (Figs. 15, 27–28). Covered with polygonal sculptures, except the regions adjacent to the genital and anal apertures and the region between these two plates. Anterior border of genital plates broader than the posterior border and the anterior margin of each genital plate located next to the apodeme delimiting the epimeres III/IV. Genital plates bear less prominent wrinkles and five pairs of small, smooth setae of length ranging from 2–6; g 1 (6), g 2 (4), g 3 (3), g 4 (4) and g 5 (3). Aggenital seta (ag) absent, anal plates broader postero-laterally, slightly below the median level. Two pairs of anal setae (an 1 & an 2, 2–3) and two pairs of adanal setae (ad 1 & ad 2, 5–7) present, all setae small, smooth, seta ad 3 absent, ad 1 located posterior to the anal plate, ad 2 inserted laterally, slightly below the middle level of anal plate. Integument of anal plate not smooth, but with feebly developed elevated areas. Legs (Figs. 16–19). All legs tridactylous, with the median claw thicker than the lateral ones. Claws bear small spines, set dorsally and with longitudinal striations. Femora of all legs with wrinkles, other segments smooth. Chaetotaxy of legs including solenidia: leg I: 1-3-3(1)-3(1)-14(1), leg II: 1-3-1(1)-2(1)-12(1), leg III: 2-3-1-2-10, and leg IV: 1-2-0-3-10 (see Table 2). LegTrochanterFemurGenuTibiaTarsusI v’ d, bv ”, v’ l’, (v), σ l’, (v), φ (ft), (tc), (it), (p), (u), (a), (pv), ωII v ’ d, bv ”, v ’ v ’’, σ l ’, (v) ft ’, (tc), (it), (p), (u), (a), pv ’, ωIII l ’, v ’ d, bv ”, v ’ l ’ l ’, v ’’ (ft), tc ’, (it), (p), (u), pv ’ IV v’ bv”, v’ - l’, (v) (ft), tc’, (it), (p), (u), pv’ Materials examined. Holotype and 15 paratypes collected from densely accumulated litter samples of A. auriculiformis, at the Calicut University Campus (11° 8’ 6.468’’ N 75° 53’ 18.5028’’ E), Malappuram (Dt.), Kerala, India, on 1.iv.2019, coll. Arun, A. Type deposition. The holotype and ten paratypes are deposited in the collections of Zoological Survey of India, Western Ghat Regional Centre, Kozhikode, Kerala, India; five paratypes are kept in the Acarology Collections, Division of Acarology, Department of Zoology, University of Calicut, Malappuram, Kerala, India. Etymology. The species epithet, “ indicus ” is derived from the name of country from where the type specimens were collected, duly considering the status as being the first species of the Family Licneremaeidae, described from India. Ecology. Large number of adults and various life stages of Licneremaeus indicus sp. nov. were found to inhabit the litter samples of A. auriculiformis. Hundreds of specimens were found to occupy all layers of litter samples, indicating their possible role in the degradation of highly recalcitrant Acacia litter. Remarks. Licneremaeus indicus sp. nov., differs from all its congeners by the possession of 14 areolae on the notogaster, clavate sensillus, presence of three notogastral bumps encompassing one areola each and by the presence of cuticular ridges on the rostral tectum between setae le and ro. The new species shows most resemblance to the oriental species, L. licnophorus in the number of notogastral setae, presence of curved bump at the level of seta dp, and polygonal sculptures on the ventral plate. However, it is distinct from L. licnophorus in the presence of areolae between the field delimited by the bases of setae da and dm, clavate nature of sensillus (flattened sensillus in L. licnophorus) and presence of pygidium on notogaster (absent in L. licnophorus).Published as part of Arun, A. & Ramani, N., 2020, Two remarkable new species of oribatid mites (Acari: Oribatida) from Acacia litter of Kerala, India, pp. 539-558 in Zootaxa 4877 (3) on pages 550-556, DOI: 10.11646/zootaxa.4877.3.7, http://zenodo.org/record/457050
Materials Photonic Bandgap in Heterostructure
No full textIn the present communication We found the large band gap in photonic heterostructure (PC1/PC2) composed of metamaterials and magnetic materials by using simple transfer matrix method. The meta-materials have the unusual electromagnetic properties having negative refractive index. The negative index material is also affected with their optical parameters like refractive index, electrical permittivity, magnetic permeability and thickness of the materials. The PC1 and PC2 are the two photonic crystal containing NIM with different thickness ratio. When these two PCs are combined and make a heterostruture of PC1/PC2 of different thicknesses ratio then the band gap of such heterostruture become large due to the band gap of PC1 and PC2. Such structure may be used as a broad band filter for TE and TM mode
CORPORATE GOVERNANCE AND CAPITAL MARKETS: A CONCEPTUAL FRAMEWORK
No full textThis paper outlines a conceptual framework of the relationship between corporate governance and two important determinants of capital market development namely, a firm’s access to finance, and its financial performance. The framework assumes that a firm’s corporate governance is simultaneously determined by a group of related governance components and other firm characteristics. Whilst the capital markets play a crucial role in enhancing corporate governance standards, the effectiveness and credibility of such effort might be constrained by poor firm-level corporate governance. Moreover, the cause and effect relationship can work in the opposite direction e.g. firm-level corporate governance quality can enhance both the firm’s ability to gain access to finance and its financial performance, which eventually lead to capital market development. The framework is primarily based on the economic approaches to corporate governance, although it recognises part of the assumptions of the stakeholder theory and the political economy aspects of corporate governance
jacob2021_series4methods
No full textData and codes for
Jacob G, Katti H, Cherian T, Das J, Zhivago KA & Arun SP (2021) A naturalistic environment to study visual cognition in unrestrained monkeys, eLife 10: e6381
jacob2021_series4methods
No full textData and codes for
Jacob G, Katti H, Cherian T, Das J, Zhivago KA & Arun SP (2021) A naturalistic environment to study visual cognition in unrestrained monkeys, eLife 10: e6381
jacob2020_multiscale
No full textData and codes for
Jacob G & Arun SP (2020) How the forest interacts with the trees: Multiscale shape integration explains global and local processing. Journal of Vision, 20: 1-2
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