8,154 research outputs found
Giant Goos-H\"anchen shift in Scattering: the role of interfering Localized Plasmon modes
The longitudinal and the transverse beam shifts, namely, the Goos-H\"anchen
(GH) and the Spin-Hall (SH) shifts are usually observed at planar interfaces.
It has recently been shown that the transverse SH shift may also arise due to
scattering of plane waves. Here, we show that analogous in-plane (longitudinal)
shift also exist in scattering of plane waves from micro/nano systems. We study
both the GH and the SH shifts in plasmonic metal nanoparticles/ nanostructures
and dielectric micro-particles employing a unified framework that utilizes the
transverse components of the Poynting vector of the scattered wave. The results
demonstrate that interference of neighboring resonance modes in plasmonic
nanostructures (e.g., electric dipolar and quadrupolar modes in metal spheres)
leads to giant enhancement of GH shift in scattering from such systems. We also
unravel interesting correlations between these shifts with the polarimetry
parameters, diattenuation and retardance.Comment: 4 pages, 3 figure
A new look at nonparasitized red cells of malaria-infected monkeys
Many reports have shown that malarial parasites can produce distinct morphological and molecular alterations in the membranes of the parasitized erythrocytes, but few studies have been carried out on nonparasitized erythrocytes of infected animals. We report here that the outer leaflet of the membrane bilayer of nonparasitized erythrocytes contains significantly larger amounts of aminophospholipids (phos-phatidylethanolamine (PE) and phosphatidylserine (PS)), than the normal red cell membrane. This alteration in nonparasitized red cells is probably caused by Ca2+-induced cross-linking of spectrin, and gradually disappears after chloroquine treatment. The external localization of PS in these cells together with defective structure of their cytoskeletal network provide a strong basis for the complications associated with malaria infection like thrombosis, infarction and severe anaemia
Polymer thin film with in situ synthesized silver nanoparticles as a potent reusable bactericide
Silver nanoparticles are well-established antibacterial agents. However, an effective design and formulation that ensures: (i) ease of synthesis and fabrication, (ii) amenability to deployment over large surfaces of variable shape, (iii) high efficacy and (iv) multiple reuses with the possibility of periodic monitoring, is yet to emerge. A nanocomposite thin film of poly(vinyl alcohol) with silver nanoparticles generated within, through a soft-chemical in situ synthesis, is shown to be a good candidate to fulfil most of the above requirements. Efficient antibacterial activity, multiple reuses and facile monitoring of the film through spectroscopy and microscopy are demonstrated. Preliminary studies demonstrate the effective bactericidal action of the thin film coating on stirring rods
Comparative evaluation of efficacy and safety of carboxymethylcellulose either alone or in combination with non-steroidal anti-inflammatory drug in the treatment of dry eye in a tertiary care teaching hospital
Background: Dry eye produces discomfort and reducedvision. The treatment of dry eyes has traditionally involved hydrating and lubricating artificial tears. The newer medications include non-steroidal anti-inflammatory drugs (NSAIDs) for the treatment of dry eye disorders. This study was designed to compare the effect of topical carboxymethylcellulose (CMC) alone or in combination with topical NSAID for the treatment of dry eye in a tertiary care teaching hospital.Methods: A total of 60 patients diagnosed with dry eye were enrolled for a study period of 1 year. Patient of either sex (male/female), age between 18 and 70 years, and all diagnosed cases of dry eye in ophthalmology outpatient department were selected. Patients (n=60) were stabilized on CMC for 2 weeks and thereafter divided into two groups. Group I (n=30) received only topical CMC; Group II (n=30) received CMC+NSAID. The patients were followed up to 12 weeks. Diagnostic tests included Schirmer’s test and tear break up time (TBUT). Ocular Surface Disease Index (OSDI) was used for assessing the Quality of Life. Analysis was done using GraphPad InStat software. p0.05) and TBUT test value (p>0.05) showed no significant difference while OSDI score revealed significant difference (p<0.05). Burning, stinging, blurring of vision, photophobia, and hyperemia were among the common adverse effects seen.Conclusion: Both groups showed significant improvement in Schirmer’s test and TBUT test value and OSDI score at the end of the study. Intergroup comparison showed a significant difference with reference to OSDI score. Patients receiving NSAID reported more adverse effects
10,21-Dimethyl-2,7,13,18-tetraphenyl-3,6,14,17-tetraazatricyclo[17.3.1.18,12]tetracosa-1(23),2,6,8(24),9,11,13,17,19,21-decaene-23,24-diol cyclohexane 0.33-solvate
The title compound, C46H40N4O2·0.33C6H12, was obtained unintentionally as a product of an attempted synthesis of a cadmium(II) complex of the [2,6-{PhSe(CH2)2N=CPh}2C6H2(4-Me)(OH)] ligand. The full tetraiminodiphenol macrocyclic ligand is generated by the application of an inversion centre. The macrocyclic ligand features strong intramolecular O—H⋯N hydrogen bonds. The dihedral angles formed between the phenyl ring incorporated within the macrocycle and the peripheral phenyl rings are 82.99 (8) and 88.20 (8)°. The cyclohexane solvent molecule lies about a site of symmetry. Other solvent within the lattice was disordered and was treated with the SQUEEZE routine [Spek (2009). Acta Cryst. D65, 148–155]
Are sanitation interventions a threat to drinking water supplies in rural India? An application of tryptophan-like fluorescence.
Open defecation is practised by over 600 million people in India and there is a strong political drive to eliminate this through the provision of on-site sanitation in rural areas. However, there are concerns that the subsequent leaching of excreta from subsurface storage could be adversely impacting underlying groundwater resources upon which rural populations are almost completely dependent for domestic water supply. We investigated this link in four villages undergoing sanitary interventions in Bihar State,
India. A total of 150 supplies were sampled for termotolerant (faecal) coliforms (TTC) and tryptophanlike
fluorescence (TLF): an emerging real-time indicator of faecal contamination. Sanitary risk inspections were also performed at all sites, including whether a supply was located within 10 m of a toilet, the recommended minimum separation. Overall, 18% of water supplies contained TTCs, 91% of which were located within 10 m of a toilet, 58% had TLF above detection limit, and sanitary risk scores were high. Statistical analysis demonstrated TLF was an effective indicator of TTC presence-absence, with a possibility of TTCs only where TLF exceeded 0.4 mg/L dissolved tryptophan. Analysis also indicated proximity
to a toilet was the only significant sanitary risk factor predicting TTC presence-absence and the most significant predictor of TLF. Faecal contamination was considered a result of individual water supply vulnerability rather than indicative of widespread leaching into the aquifer. Therefore, increasing faecal contamination of groundwater-derived potable supplies is inevitable across the country as uptake of onsite sanitation intensifies. Communities need to be aware of this link and implement suitable decentralised low-cost treatment of water prior to consumption and improve the construction and protection
of new supplies
Probing Pseudo-Dirac Neutrino through Detection of Neutrino Induced Muons from GRB Neutrinos
The possibility to verify the pseudo-Dirac nature of neutrinos is
investigated here via the detection of ultra high energy neutrinos from distant
cosmological objects like GRBs. The very long baseline and the energy range
from TeV to EeV for such neutrinos invokes the likelihood to
probe very small pseude-Dirac splittings. The expected secondary muons from
such neutrinos that can be detected by a kilometer scale detector such as
ICECUBE is calculated. The pseudo-Dirac nature, if exists, will show a
considerable departure from flavour oscillation scenario in the total yield of
the secondary muons induced by such neutrinos.Comment: 11 pages, 3figure
The STAR Photon Multiplicity Detector
Details concerning the design, fabrication and performance of STAR Photon
Multiplicity Detector (PMD) are presented. The PMD will cover the forward
region, within the pseudorapidity range 2.3--3.5, behind the forward time
projection chamber. It will measure the spatial distribution of photons in
order to study collective flow, fluctuation and chiral symmetry restoration.Comment: 15 pages, including 11 figures; to appear in a special NIM volume
dedicated to the accelerator and detectors at RHI
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