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2.
Arch Virol ; 169(7): 136, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847927

ABSTRACT

Here, we report the first detection of lymphocystis disease virus (LCDV) in Indian glass fish in the Andaman Islands, India. Microscopic examination revealed the presence of whitish clusters of nodules on the fish's skin, fins, and eyes. The histopathology of the nodules revealed typical hypertrophied fibroblasts. Molecular characterization of the major capsid protein (MCP) gene of the virus showed a significant resemblance to known LCDV sequences from Korea and Iran, with 98.92% and 97.85% sequence identity, respectively. Phylogenetic analysis confirmed that the MCP gene sequence of the virus belonged to genotype V. This study represents the first documented case of LCDV in finfish from the Andaman Islands, emphasizing the necessity for continued monitoring and research on the health of aquatic species in this fragile ecosystem.


Subject(s)
Capsid Proteins , DNA Virus Infections , Fish Diseases , Iridoviridae , Phylogeny , Animals , Fish Diseases/virology , India , Iridoviridae/genetics , Iridoviridae/isolation & purification , Iridoviridae/classification , DNA Virus Infections/virology , DNA Virus Infections/veterinary , Capsid Proteins/genetics , Fishes/virology , Genotype , Islands
3.
ISA Trans ; 147: 215-226, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38402102

ABSTRACT

A hybrid technique is proposed in this manuscript for the optimal design of an induction motor (IM) drive for the dynamic load profiles during torque and flux control. The proposed hybrid method combines a Ladder-Spherical-Evolution-Search-Algorithm (LSE) and a recalling-enhanced recurrent-neural network (RERNN), which is called an LSE-RERNN technique. The major objective of the proposed method is to minimize IM losses while maintaining control over speed and torque. The proposed method effectively tunes the gain parameter of the PI controller for flux and torque regulation. The LSE methodgenerates a set of gain parameters optimally predicted by RERNN. The method reduces losses without prior knowledge of load profiles, achieving energy savings for steady-state optimum flux. The performance of the proposed technique is done in the MATLAB and is compared with different existing techniques. The value of the proposed method for the mean is 0.328, the standard deviation (SD) is 0.00334, and the median is 0.4173. The loss of the proposed method is much less than 0.3 W while compared to different existing approaches. Moreover, the computation time of the proposed approach is lesser than the existing techniques.

4.
J Coast Conserv ; 27(2): 11, 2023.
Article in English | MEDLINE | ID: mdl-36915700

ABSTRACT

We interviewed the Nicobarese tribal community (N = 95) of Car Nicobar Island situated in the Andaman and Nicobar archipelago, India to analyze the impact of COVID-19-related restrictions on their coastal fishing activities. Our surveys revealed a significant reduction (p < 0.001) in the average monthly income and fish catches during pre and post-COVID-19 scenarios. Constraints faced during the pandemic-related restrictions and the possible solutions to reinforce the fishing activities were highlighted for sustainable resource management in Car Nicobar Island.

5.
Chemosphere ; 310: 136824, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36241111

ABSTRACT

Benthic foraminifera are increasingly used as an indicator of environmental disturbance. Their sensitivities to pollutants can be reflected by changes in assemblage, which can provide useful information about ecosystem health. This study aimed to investigate the impact of organic and inorganic pollutants on the benthic ecology of the Chennai coast, with a focus on the 2017 oil spill caused by the collision of two ships. Sediment samples collected from five distinct zones along the coast were analysed for pollutants such as polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPH), heavy metals (Cr, Cd, Pb) and total organic carbon (TOC). The maximum concentrations of Cr (137 µg/g), Cd (6.93 µg/g) and Pb (34.2 µg/g), as well as TPH (84.3 µg/g) and PAHs (227 ng/g), were observed. A total of 47 species of foraminifera were identified in this study, of which 12 were morphologically abnormal. In the low-impact zone, the species diversity index (H') was higher. TPH and PAH concentrations were positively associated with abnormal species. Pollution-resistant foraminifera species include Ammonia tepida, Elphidium discoidale, and Quinqueloculina lamarckiana, while opportunistic foraminifera include Pararotalia curryi, Nonionella stella, Rosalina globularis, and Spirillina vivipara. PAHs and heavy metals were adversely correlated with foraminiferal abundance, while TPH was positively correlated. To assess the response of the benthic ecosystem to hydrocarbon pollution, indices such as the Foraminiferal Index of Environmental Impact (FIEI), Exponential (H'bc) index and the Foraminiferal Abnormality Index (FAI) were used as environmental health proxies. FIEI, exp(H'bc) and FAI values show the impact of hydrocarbon pollution to an extent along the northern Chennai coast.


Subject(s)
Environmental Pollutants , Foraminifera , Metals, Heavy , Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Foraminifera/physiology , Geologic Sediments/analysis , Environmental Pollutants/analysis , Environmental Monitoring , Ecosystem , Cadmium/analysis , Lead/analysis , Water Pollutants, Chemical/analysis , India , Metals, Heavy/analysis , Polycyclic Aromatic Hydrocarbons/analysis
6.
J Voice ; 2022 Sep 30.
Article in English | MEDLINE | ID: mdl-36192290

ABSTRACT

Acoustic Voice Quality Index is a six-variable acoustic model for the multiparametric measurement developed by Maryn et al. Studies have provided evidence regarding the practical usefullness, internal consistency, external validity, diagnostic accuracy, and responsiveness to change of AVQI. Recently, researchers have been exploring the utility of AVQI in classifying the voice severity. The aim of the present study was to determine the diagnostic accuracy of the AVQI v.02.03 in discriminating across the perceptual levels of dysphonia severity in 18-40 years age range in Kannada speaking population; and to develop an application to depict the AVQI based severity of dysphonia. For the study, 163 individuals in normophonic and 134 individuals in dysphonic group were considered in the age range of 18-40 years. All participants were native speakers of Kannada language. The sustained vowel /a/ and reading of standard Kannada passage were considered as stimuli for extracting AVQI analysed using AVQI script version 02.03. The AVQI cut-off values obtained were 2.50 (AROC=0.894; Sensitivity= 84.7%; Specificity= 83.1%), 4.17 (AROC=0.953; Sensitivity= 84.4%; Specificity= 88.5%) and 6.23 (AROC=1.000; Sensitivity= 100%; Specificity= 100%) for normal vs. mild, mild vs. moderate and moderate vs. severe respectively. A user friendly application was developed which provides a simplified output for AVQI cut-off values which can be comprehendible by patients with voice disorder/ non-professionals and health professionals.

7.
Aquaculture ; 548: 737596, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-34720238

ABSTRACT

The present study was aimed at understanding the impact of COVID-19 pandemic related restrictions on the freshwater aquaculture sector of Andaman and Nicobar archipelago (ANI). We interviewed the freshwater fish farmers (N = 211) covering all the three districts (North and Middle, South Andaman, Nicobar district) of the archipelago. The results revealed the critical issues faced by the stakeholders such as fish seed unavailability, limitations in feeding, insufficient logistical support, movement related restrictions, lack of inputs, manpower shortages, etc. as the important constraints during lockdown. Our surveys also revealed that there was a significant reduction in the income of the farmers post COVID-19 outbreak (p < 0.001). Possible reform strategies that could promote the sector development and resilience were outlined to recover from the COVID-19 impacts. The study also highlights the significance of effective networking among the stakeholders and necessary preparedness measures to be undertaken by the fish farmers to deal with the exigencies. The study also recommends a policy framework to strengthen the planning and management of freshwater aquaculture sector towards the path of sustainability.

8.
Mar Pollut Bull ; 172: 112879, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34464820

ABSTRACT

The present study investigates the issue of marine debris and the associated soil, sediment, water quality, and microbial load from the fish landing centres (Junglighat, Chatham, Wandoor, and Guptapara) of South Andaman. The results revealed that significantly (P < 0.05) higher number and weight of marine debris was found in urban landing centres such as Chatham (21.26 ± 1.03 numbers/m2) and Junglighat (268.16 ± 27.00 g/m2), respectively. Plastic debris was found to be the most abundant type of debris, among which plastic bags were dominant. Better soil, sediment, and water quality parameters were observed in rural landing centres such as Wandoor and Guptapara, whereas microbial load was found to be higher in urban landing centres. The study recommends the imperative need to generate awareness on better management practices among the stakeholders to deal with the issue of marine debris and to aim sustainable management of the coastal environment.


Subject(s)
Waste Products , Water Quality , Animals , Environmental Monitoring , Plastics , Soil , Waste Products/analysis
9.
J Phys Condens Matter ; 33(33)2021 Jun 28.
Article in English | MEDLINE | ID: mdl-34062517

ABSTRACT

We have synthesized high-quality single crystals of SnxPb1-xTe and carried out detailed studies of the magnetotransport properties of one of the samples, Sn0.05Pb0.95Te. Longitudinal magnetoresistance increases almost linearly with increasing applied field (H) and reaches ∼310% atH= 13 T. At higher fields, both longitudinal and Hall resistance show clear Shubnikov de Haas oscillations. The oscillations are smooth and periodic, and there exists only one frequency,fα∼ 57 T. However, an additional frequency,fß∼ 69 T, appears as the angle between the field direction and the normal to the sample surface (θ) is increased. Bothfαandfßexhibitθ-dependence;fαdecreases whereasfßincreases gradually with increasingθ. The presence of two frequencies in Sn0.05Pb0.95Te indicates that there exist two Fermi surface pockets (αandßpockets). We have constructed the Landau-level fan plot and determined the Berry phase (δ) for theαpocket to beδ∼ 0.1. Thisδvalue is very close to the expected value of 0 for a topologically trivial system.

10.
Zootaxa ; 4661(1): zootaxa.4661.1.11, 2019 Aug 27.
Article in English | MEDLINE | ID: mdl-31716725

ABSTRACT

Gymnothorax andamanensis sp. nov., a new short brown moray eel, is described here on the basis of two specimens collected from Port Mout, Port Blair, South Andaman (11.659327°N; 92.696148°E), caught using baited hand-lines in a sandy habitat at a depth of less than 2 m. The species is characterized in having the dorsal-fin origin before the gill opening, pre-anal length 2.1-2.2, jaw pores with black rim, two branchial pores, predorsal vertebrae 3, preanal vertebrae 57 and total vertebrae 135-136, teeth smooth, three large fang-like median intermaxillary teeth, biserial maxillary and uniserial vomerine teeth, and dentary teeth biserial with two teeth in each side in the second row of the dentary. The new species is compared with all 10 short brown unpatterned moray eels known from the world and two from Indian waters.


Subject(s)
Eels , Gills , Animals , Ecosystem , India , Spine
11.
Phys Rev Lett ; 122(11): 116101, 2019 Mar 22.
Article in English | MEDLINE | ID: mdl-30951360

ABSTRACT

We report inelastic He atom scattering measurements of the (001) surface phonon dispersion of the topological crystalline insulator Pb_{0.7}Sn_{0.3}Se. This material exhibits a temperature-dependent topological transition, so we measure the surface dispersion curves in both the trivial and nontrivial phases. We identify that, peculiarly, most surface modes are resonances, rather than pure surface states. We find that a shear vertical surface resonance branch around 9.0 meV dramatically changes on going from the trivial to the topological phase. We associate this remarkable change with the emergence of surface Dirac fermions. We use the measured dispersion of this resonance branch to determine the corresponding mode-dependent electron-phonon coupling λ_{ν}(q).

12.
J Phys Condens Matter ; 31(28): 285802, 2019 Jul 17.
Article in English | MEDLINE | ID: mdl-30939461

ABSTRACT

We report high-precision magnetization ([Formula: see text]), magnetic susceptibility ([Formula: see text]), specific heat (C p (T, H)) and 'zero-field' electrical resistivity, [Formula: see text], data taken on Gd2Te3 single crystal over wide ranges of temperature and magnetic field (H), with either [Formula: see text]-axis or [Formula: see text]-plane. [Formula: see text] and [Formula: see text] unambiguously establish that the b-axis is the easy direction of magnetization whereas any direction in the ac-plane is a hard direction. The [Formula: see text]-type anomaly in 'zero-field' specific heat, C p (T, H = 0), and an abrupt drop in [Formula: see text] (characteristic of the paramagnetic (PM) - antiferromagnetic (AFM) phase transition) are observed at the Néel temperature, [Formula: see text] K. [Formula: see text] and C p (T,H) clearly demonstrate that [Formula: see text] shifts to lower temperatures with increasing H irrespective of whether H points in the easy or hard direction. When [Formula: see text], the [Formula: see text] isotherms at temperatures in the range 2.5 K [Formula: see text] [Formula: see text] K reveal the existence of a field-induced spin-flop (SF) transition at fields 4.0 T [Formula: see text] [Formula: see text] [Formula: see text] 4.5 T. The first principles electronic band structure and density of states calculations, based on the density functional theory, correctly predict an AFM ground state (stabilized primarily by the 4f  Gd3+ - 5p  Te2-- 4f  Gd3+ superexchange interactions) and the observed semi-metallic behavior for the Gd2Te3 compound. Moreover, these calculations yield the values [Formula: see text] [Formula: see text] for the ordered magnetic moment per Gd atom at T = 0, [Formula: see text] mJ mol-1 K-2 for the Sommerfeld coefficient for the electronic specific heat contribution and [Formula: see text] K for the Curie-Weiss temperature, respectively. These theoretical estimates conform well with the corresponding experimental values [Formula: see text] [Formula: see text], [Formula: see text] mJ mol-1 K-2 and [Formula: see text] K.

13.
J Pharm Bioallied Sci ; 10(2): 106-108, 2018.
Article in English | MEDLINE | ID: mdl-29962801

ABSTRACT

Oral cancer is the fifth most common cancer in the world, accounting for numerous deaths annually. The 5-year survival rate remains approximately 50% for oral squamous cell carcinoma (OSCC) in the past several decades. Early detection plays a vital role in the survival rate of the patients. There is no accurate, cost-effective, and reliable method for the screening of patients with OSCC. Hence, many patients are diagnosed at advanced stages. Early detection would, therefore, help to identify patients and modify treatment with close monitoring. Lab on a Chip or micro-total-analysis systems are one of the microfluidics technologies that are defined as adaptation, miniaturization, integration, and automation of analytical laboratory procedures into a single device or "chip." This technology assures the replacement of complicated techniques with miniaturized, integrated, programmed, and economical diagnostic devices. Hence, this system provides a means for rapid, automated, molecular analysis of cancer cells.

15.
Nat Commun ; 9(1): 1550, 2018 04 19.
Article in English | MEDLINE | ID: mdl-29674651

ABSTRACT

Orbital degrees of freedom can have pronounced effects on the fundamental properties of electrons in solids. In addition to influencing bandwidths, gaps, correlation strength and dispersion, orbital effects have been implicated in generating novel electronic and structural phases. Here we show how the orbital nature of bands can result in non-trivial effects of strain on band structure. We use scanning-tunneling microscopy to study the effects of strain on the electronic structure of a heteroepitaxial thin film of a topological crystalline insulator, SnTe. By studying the effects of uniaxial strain on the band structure we find a surprising effect where strain applied in one direction has the most pronounced influence on the band structure along the perpendicular direction. Our theoretical calculations indicate that this effect arises from the orbital nature of the conduction and valence bands. Our results imply that a microscopic model capturing strain effects must include a consideration of the orbital nature of bands.

16.
Anaerobe ; 51: 8-11, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29526826

ABSTRACT

Paraclostridium bifermentans (current nomenclature of Clostridium bifermentans since 2016) is a gram-positive, spore-forming anaerobic bacterium. Here, we describe two cases associated with this organism. The first, primarily a case of tubercular brain abscess where P. bifermentans was isolated as part of a polymicrobial flora, following a neurosurgical procedure for the same and the second, a case of cervical lymphadenitis from which it was isolated as the sole causative agent. There are only a few reported cases of P. bifermentans in literature and these cases illustrate the widening spectrum of infections related to it.


Subject(s)
Brain Abscess/diagnosis , Brain Abscess/pathology , Clostridium Infections/diagnosis , Clostridium Infections/pathology , Clostridium bifermentans/isolation & purification , Lymphadenitis/diagnosis , Lymphadenitis/pathology , Adult , Anti-Bacterial Agents/therapeutic use , Brain/diagnostic imaging , Brain Abscess/microbiology , Brain Abscess/therapy , Clostridium Infections/microbiology , Clostridium Infections/therapy , Clostridium bifermentans/classification , Drainage , Female , Humans , Lymphadenitis/microbiology , Lymphadenitis/therapy , Male , Tomography, X-Ray Computed
17.
Sci Rep ; 8(1): 651, 2018 01 12.
Article in English | MEDLINE | ID: mdl-29330440

ABSTRACT

Superconductivity in noncentrosymmetric compounds has attracted sustained interest in the last decades. Here we present a detailed study on the transport, thermodynamic properties and the band structure of the noncentrosymmetric superconductor La 7 Ir 3 (T c ~ 2.3 K) that was recently proposed to break the time-reversal symmetry. It is found that La7Ir3 displays a moderately large electronic heat capacity (Sommerfeld coefficient γ n ~ 53.1 mJ/mol K2) and a significantly enhanced Kadowaki-Woods ratio (KWR ~32 µΩ cm mol2 K2 J-2) that is greater than the typical value (~10 µΩ cm mol2 K2 J-2) for strongly correlated electron systems. The upper critical field Hc2 was seen to be nicely described by the single-band Werthamer-Helfand-Hohenberg model down to very low temperatures. The hydrostatic pressure effects on the superconductivity were also investigated. The heat capacity below T c reveals a dominant s-wave gap with the magnitude close to the BCS value. The first-principles calculations yield the electron-phonon coupling constant λ = 0.81 and the logarithmically averaged frequency ω ln = 78.5 K, resulting in a theoretical T c = 2.5 K, close to the experimental value. Our calculations suggest that the enhanced electronic heat capacity is more likely due to electron-phonon coupling, rather than the electron-electron correlation effects. Collectively, these results place severe constraints on any theory of exotic superconductivity in this system.

18.
Nat Commun ; 8(1): 982, 2017 10 12.
Article in English | MEDLINE | ID: mdl-29026090

ABSTRACT

A correction to this article has been published and is linked from the HTML version of this article.

19.
Nat Commun ; 8(1): 366, 2017 08 28.
Article in English | MEDLINE | ID: mdl-28848231

ABSTRACT

Topological crystalline insulators possess metallic surface states protected by crystalline symmetry, which are a versatile platform for exploring topological phenomena and potential applications. However, progress in this field has been hindered by the challenge to probe optical and transport properties of the surface states owing to the presence of bulk carriers. Here, we report infrared reflectance measurements of a topological crystalline insulator, (001)-oriented Pb1-x Sn x Se in zero and high magnetic fields. We demonstrate that the far-infrared conductivity is unexpectedly dominated by the surface states as a result of their unique band structure and the consequent small infrared penetration depth. Moreover, our experiments yield a surface mobility of 40,000 cm2 V-1 s-1, which is one of the highest reported values in topological materials, suggesting the viability of surface-dominated conduction in thin topological crystalline insulator crystals. These findings pave the way for exploring many exotic transport and optical phenomena and applications predicted for topological crystalline insulators.Probing optical and transport properties of the surface states in topological crystalline insulators remains a challenge. Here, Wang et al. demonstrate that the far-infrared conductivity of Pb1-x Sn x Se (x = 0.23-0.25) single crystals is dominated by the surface states where carriers show a high surface mobility of 40,000 cm2 V-1 s-1.

20.
J Parasit Dis ; 41(2): 593-595, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28615886

ABSTRACT

In the present study, occurrence of branchial parasitic cymothoid, Ryukyua circularis from the marine finfish, Amblygaster sirm is reported for the first time from Andaman Islands. Morphological characterization was carried out which confirmed the parasite as R. circularis. Molecular characterization using 28S rDNA revealed 443 bp sequence which has been submitted to NCBI GenBank under the accession no. KX090447. Ten female and one male parasite (R. circularis) were collected from the branchial cavity of the individual host fishes (A. sirm). The displacement of gill filament and cavity formation in the gill chamber of the host fish was observed. The report of this species from Andaman Islands gives further information on its geographic range extension, since they are currently known from West coast of India and Thailand.

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