15,201 research outputs found
Type IIA Orientifold Limit of M-Theory on Compact Joyce 8-Manifold of Spin(7)-Holonomy
We show that M-theory compactified on a compact Joyce 8-manifold of
-holonomy, which yields an effective theory in with = 1
supersymmetry, admits at some special points in it moduli space a description
in terms of type IIA theory on an orientifold of compact Joyce 7-manifold of
-holonomy. We find the evidence in favour of this duality by computing the
massless spectra on both M-thory side and type IIA side. For the latter, we
compute the massless spectra by going to the orbifold limit of the Joyce
7-manifold.Comment: 26 pages, 2 eps figures, Latex file, two references and one footnote
added, corrected some typo
Composition of primary cosmic rays near the knee
The size dependence of high energy muons and the size spectrum obtained in the air shower experiment suggest that the mean mass of cosmic rays remains nearly constant at approx 15 up to 5 x 1000,000 GeV and becomes one beyond. The composition model in which nuclei are removed spectrum steepens at 6.7 x 10 power GeV due to leakage from the galaxy, which explains the data which are consistent with data from other experiments
Primary sclerosing cholangitis in India
Six patients with PSC have been diagnosed and followed up at a centre in Northern India for periods upto 4 years. They all presented with cholestatic jaundice and cholangitis, but one of them subsequently presented with variceal haemorrhage. Cholangiographic features were the most characteristic and included irregular narrowing and segmental dilatation of the biliary radicles giving them a beaded appearance. Treating them was most frustrating. Two of them died of hepatic encephalopathy, others have also continued to be sick during the follow-up
Kahler Independence of the G2-MSSM
The G2-MSSM is a model of particle physics coupled to moduli fields with
interesting phenomenology both for colliders and astrophysical experiments. In
this paper we consider a more general model - whose moduli Kahler potential is
a completely arbitrary G2-holonomy Kahler potential and whose matter Kahler
potential is also more general. We prove that the vacuum structure and spectrum
of BSM particles is largely unchanged in this much more general class of
theories. In particular, gaugino masses are still supressed relative to the
gravitino mass and moduli masses. We also consider the effects of higher order
corrections to the matter Kahler potential and find a connection between the
nature of the LSP and flavor effects.Comment: Final version, matches the version published in JHE
Macro-anatomical variation of the olfactory apparatus in some Indian teleosts with special reference to their ecological habitat
The anatomy of the peripheral olfactory apparatus (i.e. olfactory lamellae, olfactorychambers, accessory nasal sacs, olfactory nerve tracts, olfactory bulbs and brain) of some teleosts, viz. Pseudapocryptes lanceolatus (Bloch and Schneider, 1801) — an air breathing mudskipper, Lepidocephalichthys guntea (Hamilton, 1822) — a freshwater scavenger fish and Mastacembelus armatus (Lacepède, 1800) — a freshwater potamodromous fish, has been studied in relation to their specific ecological habitat. Live, adult, sex-independent fish species were collected from the local markets of West Bengal, India, and acclimatised with the laboratory conditions (for 72 h at 32°C). The specimens were anaesthetised by MS-222 (dose: 100–200 mg/L). Olfactory apparatuses were dissected out and fixed inaqueous Bouin’s solution. The macro- and microstructures (using haematoxylin and eosin) of the olfactory apparatuses were examined under binocular light microscope (LM) and trinocular LM (Primo Star; Carl Zeiss Microscpy, GmbH, Germany) respectively. P. lanceolatus possesses unilamellar olfactory apparatus at therounded snout, whereas L. guntea shows small rosette with 18 to 24 lamellae oneither side of the elliptical snout. Elongated olfactory rosette (number of lamellae ranges from 60 to 76) is present at the pointed snout of M. armatus. Morpho-anatomical variation in snout structure of the respective species is an indicative of divergence in ecological habitat, but variation in olfactory apparatus is significant for species-specific differentiation. Pseudostratified olfactory neuroepithelial components (i.e. sensory receptor cell, supporting cell and basal cell) show striking similarities amongst these species. Therefore comparative anatomical changes of the snout and olfactory apparatus are not only representing ecological habitat based on interspecific variation, but may also indicate the phylogenetic relation amongst said species
Measurement of the iron spectrum from 60 to 200 GeV per nucleon
The high energy gas Cerenkov Spectrometer (HEGCS) was flown by balloon from Palestine, Texas on September 30, 1983. The instrument maintained an altitude of 118,000 ft (4.7 g/sq cms) for 6 hours. Details of the ongoing data analysis and preliminary results on the Fe spectrum to 10 to the 13th power eV/nucleus are given
Hepatitis B, C and D viral markers in multitransfused thalassemic children: long term complications and present management
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