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To compare nasal mucociliary clearance in adult non-smokers, cigarette smokers and bidi smokers using the methylene blue dye test.
The study sample consisted of 20 non-smokers, 20 cigarette smokers and 20 bidi smokers (age range, 20–40 years). A single drop of the methylene blue dye was placed at the anterior end of the inferior turbinate of the participants’ nasal cavity. The distance travelled by the methylene blue in 15 minutes inside the nasal cavity was measured. Nasal mucociliary clearance of the three groups was compared using the Kruskal Wallis test.
Nasal mucociliary clearance was significantly decreased in bidi smokers as compared to cigarette smokers and non-smokers (p < 0.05). Multivariate analysis revealed a significant association between nasal mucociliary clearance and bidi smoking, number of cigarettes or bidis smoked per day, and pack-years (all p < 0.05).
Nasal mucociliary clearance measurement is a simple and useful index for assessing the effect of smoking on the mucociliary activity of nasal mucosa.
Background: MRI criteria are used to support multiple sclerosis diagnosis and evolution. However, normal age-related lesions (ARLs) can be cofounded with MS white matter lesion (MSL). Methods: Two Multiparametric 7T MRI scans 4 motnhs apart from 5 relapsing MS (RMS) patients were analyzed and compared to 5 matched healthy controls (HC) aiming to differentiate MSLs from ARLs. Six-echo GRE, FLAIR and MPRAGE sequences were acquired. Results: Average size of ARLs was 51 mm3 and of MSLs was 69 mm3 (p=0.27). Both have the same general appearance on FLAIR and MPRAGE contrasts, but different contrast on the R2* and QS maps. Inter-visit variation on MPRAGE was significantly higher in MSLs. Inter-visit signal change in the other contrasts (QSM, R2* and FLAIR) was not significant. Conclusions: R2*, QS maps and inter-visit variation using MPRAGE allowed differentiating MSLs from ARLs in 5 RMS with mean long term disease duration. This could improve correct early diagnosis and accurate lesion load accumulation evolution.
To determine the prognostic value of laryngoscopy in predicting the recovery of unilateral vocal fold paralysis.
A prospective study was carried out of all patients with unilateral vocal fold paralysis without a progressive lesion or arytenoid dislocation.
Among the 66 candidates, 15 recovered. Patients with interarytenoid paralysis (p < 0.001) or posterolateral tilt of the arytenoid (p = 0.028) had less chance of recovery. Among 51 patients who did not recover, 25.49 per cent regained phonatory function by compensatory movement of the normal side; the rest required an intervention. Intervention requirement was significantly less for those patients who had isolated glottic level compensation. The paralysed vocal fold was at the same level in 32.35 per cent of patients, higher in 38.23 per cent and lower in 29.42 per cent. In those in whom vocal folds were in the abducted position (46.67 per cent), the affected vocal fold was at a lower position on phonation. Inter-observer reliability assessment revealed excellent to good agreement for all criteria.
Interarytenoid paralysis and posterolateral tilt of the arytenoid were predictors of poor recovery.
Debates about secularism in post-independence India have often revolved around the visions of two of the country's founding fathers—M. K. Gandhi and Jawaharlal Nehru. A sharp distinction is drawn between them by those who argue that the Gandhian model (or, what in common parlance and state discourses is called communal harmony) stems from Indian cultural and religious values, and lies beyond the realm of the state. The Nehruvian model, however, is a state project through and through. This article transcends this dichotomy to show that the association of Nehru and Gandhi with these models does not necessarily mean that secularism and communal harmony faithfully reflect their ideas and, despite the differences in their aims and methods, both models are united in the discourses and practices of the state as strategies of ‘governmentality’. After redefining the core of communal harmony as reciprocity (rather than tolerance), I show how it is performed, how it supplements the state's efforts to keep the peace in a religiously plural society by the force of law, and shores up the state's legitimacy deficit. However, the state's simultaneous involvement in Nehruvian and Gandhian projects is not an innocuous fact because it undermines the state's constitutional and secular obligations to non-discriminatory citizenship in the Indian nation. The argument is that the state's endorsement of dargah-centred Islamic piety as an exemplary site of communal harmony and particular ideas of the Indian nation legitimized by communal harmony ‘problematizes’ the national belonging of certain kinds of pious Muslims.
To study the effect of explosive field emission cathodes on high power microwave generation, experiments were conducted on a reflex triode virtual cathode oscillator. Experimental results with cathodes made of graphite, stainless steel nails, and carbon fiber (needle type) are presented. The experiments have been performed at the 1 kJ Marx generator (200 kV, 300 ns, and 9 kA). The experimentally obtained electron beam diode perveance has been compared with the one-dimensional Child-Langmuir law. The cathode plasma expansion velocity has been calculated from the perveance data. It was found that the carbon fiber cathode has the lowest cathode plasma expansion velocity of 1.7 cm/μs. The radiated high power microwave has maximum field strength and pulse duration for the graphite cathode. It was found that the reflex triode virtual cathode oscillator radiates a single microwave frequency with the multiple needle cathodes for a shorter (<200 ns full width at half maximum) voltage pulse duration.
Recent Genome-Wide Association Studies (GWAS) have identified four low-penetrance ovarian cancer susceptibility loci. We hypothesized that further moderate- or low-penetrance variants exist among the subset of single-nucleotide polymorphisms (SNPs) not well tagged by the genotyping arrays used in the previous studies, which would account for some of the remaining risk. We therefore conducted a time- and cost-effective stage 1 GWAS on 342 invasive serous cases and 643 controls genotyped on pooled DNA using the high-density Illumina 1M-Duo array. We followed up 20 of the most significantly associated SNPs, which are not well tagged by the lower density arrays used by the published GWAS, and genotyping them on individual DNA. Most of the top 20 SNPs were clearly validated by individually genotyping the samples used in the pools. However, none of the 20 SNPs replicated when tested for association in a much larger stage 2 set of 4,651 cases and 6,966 controls from the Ovarian Cancer Association Consortium. Given that most of the top 20 SNPs from pooling were validated in the same samples by individual genotyping, the lack of replication is likely to be due to the relatively small sample size in our stage 1 GWAS rather than due to problems with the pooling approach. We conclude that there are unlikely to be any moderate or large effects on ovarian cancer risk untagged by less dense arrays. However, our study lacked power to make clear statements on the existence of hitherto untagged small-effect variants.
Gas phase processing rakes laser deposition over large areas possible but homogeneous nucleation of large atomic clusters must be avoided if films are to be produced. Clusters can be highly variable in size from a few atoms to significant fractions of a micrometer. If conditions do not allow for complete quenching of the clusters produced in the gas phase, these clusters can arrive at the substrate with sufficient energy to self sinter into homogeneous films which are substantially different from metallic films grown by thermal techniques. Using transmission electron microscopy (TEM), we have characterized the microstructure of thin metallic films deposited by laser breakdown chemical vapor deposition and identified a range of deposition conditions which can lead from powders to homogeneous polycrystalline films and mixed phase materials. Gas phase nucleation is dependent on reactant partial pressures and the gas phase quench rate which car be varied in part by adjusting the H2 content of the source gas. Manipulation of these parameters can vary powder size from about one micrometer to less than 2 nanometers. Variation of the quench rate during the deposition of polycrystalline films varies the grain size in the films. heating the substrate drastically changes the conditions under which the film is formed and as a consequence, can radically alter the microstructure of the film itself.
GaN films were grown on c-plane (0001), a-plane (1120) and r-plane (1102) sapphire substrates by the ECR-assisted MBE method. The films were grown using a two-step growth process, in which a GaN buffer is grown first at relatively low temperatures and the rest of the film is grown at higher temperatures. RHEED studies indicate that this growth method promotes lateral growth and leads to films with smooth surface morphology. The epitaxial relationship to the substrate, the crystalline quality and the surface morphology were investigated by RHEED, X-ray diffraction and SEM studies.
The carbon nanotubes and carbon nanobtube junctions have recently emerged as excellent candidates for use as the building blocks in the formation of nanoscale electronic devices. Single wall carbon nanotubes, as molecular wires, could be used as nanoscale interconnects, where as complex junctions of nanotubes of different chirality can be used as rectifying and transiting devices. It has been shown that pentagon-heptagon defect is responsible for the creation of simple hetero-junctions. Complex junctions, such as 3-termianl T-junctions and Y-junctions require entirely different arrangement of defects. These 3-terminal junctions form prototypes of nanoscale tunnel devices made entirely of carbon. Furthermore, either n-type or p-type doping of the semiconducting portion of these complex junctions should yield Schottky barrier type devices. We also investigate simple wires and junctions of boron and nitrogen (III-V elements) and compare with those of carbon. The structural and electronic properties on nanotubes and nanotube junctions (carbon as well as BN) are studied using a generalized tight-binding molecular dynamics (GTBMD) scheme.
The development of micro- and nanofabrication, their applications, and their dependent industries has progressed to a point where a bifurcation of technology development will likely occur. On the one hand, the semiconductor industry (at least in the USA) has decided to develop EUV and SCALPEL to meet its future needs. Even if the semiconductor industry is successful in this (which is by no means certain) such tools will not be useful in most other segments of industry and research that will employ nanolithography. As examples, MEMS, integrated optics, biological research, magnetic information storage, quantum-effect research, and multiple applications not yet envisioned will not employ the lithography tools of the semiconductor industry, either because they are too expensive, insufficiently flexible, or lacking in accuracy and spatial-phase coherence. Of course, direct-write electron-beam lithography can meet many of these non-semiconductor-industry needs, but in other cases a technique of higher throughput or broader process-latitude is necessary. Our experience at MIT in applying low-cost proximity x-ray nanolithography to a wide variety of applications leads us to conclude that this technology can provide an alternative path of a bifurcation. A new projection lithography technique, zone-plate-array lithography (ZPAL), does not require a mask, can operate from UV to EUV to x-rays, and has the potential to reach the limits of the lithographic process.
We report the fabrication of a one dimensional microcavity structure embedded with colloidal CdSe/ZnS core/shell quantum dots using solution processing. The microcavity structures were fabricated by spin coating alternating layers of polymers of different refractive indices (poly-vinylcarbazole, and poly-acrylic acid) to form the distributed Bragg reflectors (DBRs). Greater than 90% reflectivity was obtained using ten periods of the structure. The one dimensional microcavity was formed by sandwiching a λ/n thick defect layer between two such DBRs. The microcavity demonstrated directionality in emission and well behaved dispersion characteristics. Room temperature time-resolved photoluminescence measurements carried out on this structure showed six fold enhancement of spontaneous emission rate. The photoluminescence decay time of the quantum dots was found to be ∼ 1 ns while for the quantum dots embedded in the microcavity it was ∼150 ps.