Lesions mimicking lacrimal gland pleomorphic adenoma

Aim: To report a series of patients with lacrimal gland lesions simulating the clinicoradiological features of lacrimal gland pleomorphic adenoma (LGPA). Methods: Multicentre retrospective, interventional case series. Clinical records of all patients with lesions mimicking LGPA seen in five orbital units were reviewed. Results: The study included 14 patients (seven men and seven women) with a mean age of 50.9 years. The diagnosis of LGPA was made in all cases by experienced orbital surgeons, based on clinicoradiological features, and lacrimal gland excision was performed. Postoperative histology revealed lymphoma (four patients), chronic dacryoadenitis (three patients), adenoid cystic carcinoma (two patients), Sjogren's syndrome (two patients), cavernous haemangioma (one patient), benign lymphoid hyperplasia (one patient) and granulomatous dacryoadenitis (one patient). Comparison with the total number of histologically confirmed LGPA cases seen during the study period revealed that 22.6% of cases of suspected LGPA were misdiagnosed based on clinicoradiological criteria. Conclusions: Many different lesions may mimic the clinicoradiological features of LGPA. The accepted clinicoradiological criteria used for the diagnosis of LGPA have a high false-positive rate, even in experienced hands. Based on this study, the authors believe that fine-needle aspiration biopsy or intraoperative biopsy and frozen section diagnosis may help reduce unnecessary lacrimal gland excision.Venkatesh C Prabhakaran, Paul S Cannon, Alan McNab, Garry Davis, Brett O’Donnell, Peter J Dolman, Raf Ghabrial, Dinesh Selv

Quantitative determination of loss in yield of black pepper (Piper nigrum L.) in Kannur District (Kerala, India)

A method for estimation of yield loss (including stand loss) in black pepper (Piper nigrum) due to various factors was developed. The method was applied for estimating the loss in yield of black pepper due to incidence of pests, diseases and drought in Kannur District (Kerala, India) during 1989-1992. The average annual yield loss in black pepper due to these factors was around 33 per cent. The major contributors towards stand loss, was foot rot caused by Phythopthora capsici contributing to 9 per cent loss followed by drought. Among the causal factors contributing to yield loss the most disastrous was incidence of poilu beetle (Longitarsus nigripennis) which accounted for about 13 per cent loss followed by fungal poilu caused by Colletotrichum gleosporioides. The percentage avoidable loss in yield by adopting plant protection measures was estimated to be around 43 per cent. &nbsp

Did human DRD2 haplotypes originate in India? A survey of haplotype frequencies and linkage disequilibrium in the tribes of Eastern Ghats, South India

In recent years, a possible role of the dopamine D2 receptor (DRD2) locus has been reported in various fields like the etiology of alcoholism, neuropsychiatric disorders, etc. Therefore, it has been the focus of considerable attention. DNA analysis has made it easier to study haplotypes, arrays of alleles at closely linked loci along the chromosome. These regions are short enough to show little or no recombination, and behave as blocks that might have ancient origins. Scoring these markers as haplotypes, allows analysis both in terms of haplotype frequencies and identity in terms of linkage disequilibrium. The human dopaminergic system is an important focus of study in the fields of neuropsychiatry and pharmacology; it is also a promising nuclear DNA marker in studies of human genome diversity. Haplotype frequencies and linkage disequilibrium for the dopamine D2 receptor gene (DRD2) were determined in 197 unrelated individuals from four tribal populations of the Eastern Ghats, an important region of India. The three marker systems in this study are highly polymorphic in all the four tribal populations and the haplotype system showed high levels of heterozygosity than the Nilgiri Hill tribes and those in other parts of the world, except Africa. Out of the possible eight haplotypes, seven are commonly shared by all the populations. The ancestral allele B2D2Al accounts for 0.028 to 0.166, which was present in all the groups consistently. The linkage disequilibrium was statistically significant in all the populations. The results show a chance of Indian origin or back migration of human DRD2 haplotypes. Data obtained in this study on DRD2 represent one of the small, but growing number of datasets examining disequilibrium and haplotype frequencies in human populations and also indicate that the gene flows from the Eastern Ghats to the Western Ghats. These populations might be one of the oldest among other Indian populations

Single gap superconductivity in beta-Bi2Pd

beta-Bi2Pd compound has been proposed as another example of a multi-gap superconductor [Y. Imai et al., J. Phys. Soc. Jap. 81, 113708 (2012)]. Here, we report on measurements of several important physical quantities capable to show a presence of multiple energy gaps on our superconducting single crystals of beta-Bi2Pd with the critical temperature Tc close to 5 K. The calorimetric study via a sensitive ac technique shows a sharp anomaly at the superconducting transition, however only a single energy gap is detected. Also other characteristics inferred from calorimetric measurements as the field dependence of the Sommerfeld coefficient and the temperature and angular dependence of the upper critical magnetic field point unequivocally to standard single s-wave gap superconductivity. The Hall-probe magnetometry provides the same result from the analysis of the temperature dependence of the lower critical field. A single-gapped BCS density of states is detected by the scanning tunneling spectroscopy measurements. Then, the bulk as well as the surface sensitive probes evidence a standard conventional superconductivity in this system where the topologically protected surface states have been recently detected by ARPES [M. Sakano et al., Nature Comm. 6, 8595 (2015)] .Comment: 7 pages, 4 figures, 1 tabl

Recent trends in cephalopod fishery of Kerala coast

Since the Cephalopods have emerged as a valuable resource in recent times because of the demand in export trade, constant monitoring of the fishery, resource position and relevant biological aspects has become imperative. The resource characteristics and biological aspects of cephalopods are being regularly monitored at Vizhinjam, Cochin and Calicut by CMFRI Scientists, Dr. N. Ramachandran, Shri. K. Prabhakaran Nair, Smt. V. Kripa and Shri. G.P. Kumaraswamy Achari

Electric field control of the magnetic chiralities in ferroaxial multiferroic RbFe(MoO4)2

The coupling of magnetic chiralities to the ferroelectric polarisation in multiferroic RbFe(MoO$_4$)$_2$ is investigated by neutron spherical polarimetry. Because of the axiality of the crystal structure below $T_\textrm{c}$ = 190 K, helicity and triangular chirality are symmetric-exchange coupled, explaining the onset of the ferroelectricity in this proper-screw magnetic structure - a mechanism that can be generalised to other systems with "ferroaxial" distortions in the crystal structure. With an applied electric field we demonstrate control of the chiralities in both structural domains simultaneously.Comment: 5 pages, 4 figure

Spin correlations among the charge carriers in an ordered stripe phase

We have observed a diffuse component to the low-energy magnetic excitation spectrum of stripe-ordered La5/3Sr1/3NiO4 probed by neutron inelastic scattering. The diffuse scattering forms a square pattern with sides parallel and perpendicular to the stripe directions. The signal is dispersive, with a maximum energy of ~10 meV. Probed at 2 meV the scattering decreases in strength with increasing temperature, and is barely visible at 100 K. We argue that the signal originates from dynamic, quasi- one-dimensional, antiferromagnetic correlations among the stripe electrons.Comment: 4 pages, 4 figures. To be published in Physical Review Letter

Hall Effect in Charged Conducting Ferroelectric Domain Walls

Enhanced conductivity at specific domain walls in ferroelectrics is now an established phenomenon. Surprisingly, however, little is known about the most fundamental aspects of conduction. Carrier types, densities and mobilities have not been determined and transport mechanisms are still a matter of guesswork. Here we demonstrate that intermittent-contact atomic force microscopy (AFM) can detect the Hall effect in conducting domain walls. Studying YbMnO(3) single crystals, we have confirmed that p-type conduction occurs in tail-to-tail charged domain walls. By calibration of the AFM signal, an upper estimate of ∼1 × 10(16) cm(−3) is calculated for the mobile carrier density in the wall, around four orders of magnitude below that required for complete screening of the polar discontinuity. A carrier mobility of∼50 cm(2)V(−1)s(−1) is calculated, about an order of magnitude below equivalent carrier mobilities in p-type silicon, but sufficiently high to preclude carrier-lattice coupling associated with small polarons

INTERACTION OF TWO FLAVONOIDS WITH CALF THYMUS DNA: A MULTI - SPECTROSCOPIC, ELECTROCHEMICAL AND MOLECULAR MODELLING APPROACH

Interaction of naturally occurring bioactive flavonoids 5,6,7-trihydroxyflavone (Baicalein) and 7,8-dihydroxyflavone (DHF) binding with calf thymus deoxyribose nucleic acid (dsDNA) was studied by employing UV absorption, fluorescence, circular dichroism, cyclic voltammetric and molecular modeling techniques. All studies were confirmed that the structural changes of DNA binding to the flavonoid. From the CV results positive shift in peak potential and increased peak current of the flavonoid in the presence of DNA and then the fluorescence quenching of DNA-flavonoids system indicated the intercalative mode of binding between flavonoid and DNA. CD studies suggest the conformational changes in DNA upon interaction with the flavonoids. Molecular docking simulation methods are used as tools to delineate the binding mode and probable location of the flavonoids and their effects on the stability and conformation of Ct-(ds) DNA. Furthermore, Baicalein can bind with more potential with Ct-(ds) DNA than DHF. This is helpful to understand the molecular aspects of binding mode and provides direction for the use and the design of new effective therapeutic agents. These results could provide useful information for insight into the pharmacological mechanism of flavonoids

Performance Evaluation and Experimental Studies on Metallised Gel Propellants

Metallised gel propellants offer higher specific impulse and volumetric loading, reduced vaporisation loss, spillage and slosh problems and easy storage in comparison to the conventional liquid propellants. Theoretical performance analysis of gel propellant containing Al in unsymmetrical dimethyl hydrazine-dinitrogen tetroxide (UDMH-N/sub 2/O/sub 4} system shows peak Isp (vacuum condition) of 316.7 s and 318.3 s at oxidiser/fuel (O/f) ratios of 1.5 and 1.0, respectively for 30 per cent and 40 per cent UDMH-Al gel propellants, under standard conditions. The effect of other parameters like area ratio and chamber pressure on performance has been brought out in view of mission oriented applications. Aluminium has been found to be a better choice over magnesium in metallised gel propellants. Experimental studies on UDMH gellation using propellant grade (15 micrometer)and pyrotechnic grade (1.5 micrometer)Al in 500g batch level show that gellant(methyl cellulose) concentration could be reduced by 50 percent using pyrotechnic grade Al. The pseudoplastic-thixotropic behaviour, flow rate through die holes, burst pressure tests and bulk density are studied. UDMH -25 to 30 per cent Al gels with both grades of Al are found to be stable, pseudoplastic (shear thinning) and thixotropic (time-dependent shear thinning), but their flow pattern through die holes differ in nature