A study of neck secondaries in pharyngeal and laryngeal malignancies.

Lymphatic metastasis is the most important mechanism in the spread of head and neck malignancies. The rate of metastasis probably reflects the aggressiveness of the primary tumour and is an important prognosticator. Not only the presence, but also the number of nodal metastases, the level in the neck, the size of the nodes and the presence of extracapsular spread are important prognostic factors. Majority of the cervical metastases were due to squamous cell carcinoma of the head and neck. • Certain primary sites had a predilection for certain group of nodes. • Thus in this study, the incidence of cervical nodal metastasis is highest for: i. Nasopharyngeal tumours (100%) followed by ii. Hypopharyngeal tumours (87%) iii. Oropharyngeal tumours (83%) and iv. Laryngeal tumours (57%) • Lesions of nasopharynx metastasise to levels II and V. • Lesions of oropharynx metastasise to levels II, III and I. • Lesions of hypopharynx metastasise to II, III and IV and a small proportion to level VI. • Lesions of larynx metastasise to levels II and III and a small proportion to levels IV and VI. • Most of the patients presented with positive nodes belonged to N2 stage followed by patients in N1 stage. • Jugulodigastric nodes (level II) are involved more often than other groups or other levels of nodes. • In most of the cases, increasing size of the primary had increasing number of nodes as well as an increasing ‘N’ stage

Antimycobacterial activity of cyanobacterial species isolated from the coastal regions of Tamil Nadu

1165-1174The extract of Geitlerinema carotinosum CNP 4003 showed promising antimicrobial activity (100 and 1000 µg/disc/well) against E. coli ATCC 35218, S. aureus ATCC 25923, and M. smegmatis with inhibition zones of 6, 8, and 11 mm, respectively. In addition, the extract also exhibited cytotoxic activity (IC50 = 175 μg/ml) against mammalian (HepG2) liver cancer cell lines. Therefore, the crude extract was fractionated using column chromatography technique and the active fractions were identified. The active fractions tested against HepG2 cell line showed 95 % hemolytic activity at the concentration of 375 µg/ml with IC50 as 63 μg/ml. Further, the compounds in the active fractions were analyzed and the results indicated the presence of indoles, terpenes, and peptides. The chemical composition of the active fraction was analyzed by using gas chromatography-mass spectrometry (GC-MS). The potential antimycobacterial strain G. carotinosum CNP 4003 was confirmed by molecular characterization and the DNA sequence was deposited in the gene bank

Protein complex directs hemoglobin-to-hemozoin formation in Plasmodium falciparum

Malaria parasites use hemoglobin (Hb) as a major nutrient source in the intraerythrocytic stage, during which heme is converted to hemozoin (Hz). The formation of Hz is essential for parasite survival, but to date, the underlying mechanisms of Hb degradation and Hz formation are poorly understood. We report the presence of a ∼200-kDa protein complex in the food vacuole that is required for Hb degradation and Hz formation. This complex contains several parasite proteins, including falcipain 2/2', plasmepsin II, plasmepsin IV, histo aspartic protease, and heme detoxification protein. The association of these proteins is evident from coimmunoprecipitation followed by mass spectrometry, coelution from a gel filtration column, cosedimentation on a glycerol gradient, and in vitro protein interaction analyses. To functionally characterize this complex, we developed an in vitro assay using two of the proteins present in the complex. Our results show that falcipain 2 and heme detoxification protein associate with each other to efficiently convert Hb to Hz. We also used this in vitro assay to elucidate the modes of action of chloroquine and artemisinin. Our results reveal that both chloroquine and artemisinin act during the heme polymerization step, and chloroquine also acts at the Hb degradation step. These results may have important implications in the development of previously undefined antimalarials

Cellular Automata with Synthetic Image A Secure Image Communication with Transform Domain

    Image encryption has attained a great attention due to the necessity to safeguard confidential images. Digital documents, site images, battlefield photographs, etc. need a secure approach for sharing in an open channel. Hardware – software co-design is a better option for exploiting unique features to cipher the confidential images. Cellular automata (CA) and synthetic image influenced transform domain approach for image encryption is proposed in this paper. The digital image is initially divided into four subsections by applying integer wavelet transform. Confusion is accomplished on low – low section of the transformed image using CA rules 90 and 150. The first level of diffusion with consecutive XORing operation of image pixels is initiated by CA rule 42. A synthetic random key image is developed by extracting true random bits generated by Cyclone V field programmable gate array 5CSEMA5F31C6. This random image plays an important role in second level of diffusion. The proposed confusion and two level diffusion assisted image encryption approach has been validated through the entropy, correlation, histogram, number of pixels change rate, unified average change intensity, contrast and encryption quality analyses

Simulation of Guided Wave Propagation in Isotropic and Composite Structures using LISA

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97117/1/AIAA2012-1387.pd

Structure and vibrational properties of carbon tubules

The structure of multilayered carbon tubules has been investigated by electron microscopy and X-ray diffraction. The structure of tubules is characterized by disorder in the stacking of cylindrical graphene sheets. Raman scattering measurements have been carried out in tubules and compared with graphite. The observed features in the Raman spectra in tubules can be understood in terms of the influence of disorder. The additional Raman modes predicted for single layer carbon tubules have not been observed

Evaluation of classical precipitation descriptions for γ′′(Ni3Nb−D022) in Ni-base superalloys

The growth/coarsening kinetics of γ′′(Ni3Nb−D022) precipitates have been found by numerous researchers to show an apparent correspondence with the classical (Ostwald ripening) equation outlined by Lifshitz, Slyozov and (separately) Wagner for a diffusion controlled regime. Nevertheless, a significant disparity between the actual precipitate size distribution shape and that predicted by LSW is frequently observed in the interpretation of these results, the origin of which is unclear. Analysis of the literature indicates one likely cause for this deviation from LSW for γ′′ precipitates is the “encounter” phenomenon described by Davies et al. (Acta Metall 28(2):179–189, 1980) that is associated with secondary phases comprising a high volume fraction. Consequently, the distributions of both γ′′ precipitates described in the literature (Alloy 718) and measured in this research in Alloy 625 are analysed through employing the Lifshitz–Slyozov-Encounter-Modified (LSEM) formulation (created by Davies et al.). The results of the LSEM analysis show good far better agreement than LSW with experimental distributions after the application of a necessary correction for what is termed in this research as “directional encounter”. Moreover, the activation energy for γ′′ coarsening in Alloy 625 shows conformity with literature data once the effect of heterogeneous (on dislocations) precipitate nucleation at higher temperatures is accounted for

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

Luminescence constitutes a unique source of insight into hot carrier processes in metals, including those in plasmonic nanostructures used for sensing and energy applications. However, being weak in nature, metal luminescence remains poorly understood, its microscopic origin strongly debated, and its potential for unravelling nanoscale carrier dynamics largely unexploited. Here, we reveal quantum-mechanical effects emanating in the luminescence from thin monocrystalline gold flakes. Specifically, we present experimental evidence, supported by first-principles simulations, to demonstrate its photoluminescence origin when exciting in the interband regime. Our model allows us to identify changes to the measured gold luminescence due to quantum-mechanical effects as the gold film thickness is reduced. Excitingly, such effects are observable in the luminescence signal from flakes up to 40 nm in thickness, associated with the out-of-plane discreteness of the electronic band structure near the Fermi level. We qualitatively reproduce the observations with first-principles modelling, thus establishing a unified description of luminescence in gold and enabling its widespread application as a probe of carrier dynamics and light-matter interactions in this material. Our study paves the way for future explorations of hot-carriers and charge-transfer dynamics in a multitude of material systems.Comment: Main text 21 pages and 4 figures. Supplemental Information 33 pages and 17 figure

Detection of short-period coronal oscillations during the total solar eclipse of 24 october, 1995

An experiment to search for short-period oscillations in the solar corona was conducted during the total solar eclipse of 1995 October 24 at Kalpi, India. The intensity in the continuum, centred around 5500 Å and with a passband having a half-width of 240 Å, was recorded at a counting rate of 20 Hz using a thermoelectric-liquid cooled photomultiplier. The power-spectrum analysis of the data reveals that most of the power is contained in 6 frequencies below 0.2 Hz. A least-square analysis gives the periods of the 6 frequency components to be 56.5, 19.5, 13.5, 8.0, 6.1, and 5.3 s. These oscillations are found to be sinusoidal, and their amplitudes are found to lie in the range 0.2-1.3% of the coronal brightness. Assuming these oscillations to be fast magnetosonic modes, the calculations indicate the availability of enough flux for the heating of the active regions in the solar corona