3,632 research outputs found
arrostii roots
A new acylated and triterpenoidal saponin, named GS1, was isolated from the roots of Gypsophila arrostii Guss. On the basis of acid hydrolysis, comprehensive spectroscopic analyses and comparison with spectral data of known compounds, its structure was established as 3-O--D-xylopyranosyl-(12)-[-D-xylopyranosyl-(13)]--D-glucopyranosyl-{21-O-[(E)-3,4,5trimethoxycinnamoyl]}21-hydroxygypsogenin 28-O--D-glucopyranosyl-(12)- [-D-arabinopyranosyl-(13)]--D-xylopyranosyl-(13]--L-rhamnopyranosyl ester. This article deals with the isolation and structural elucidation of new acylated and oleanane-type saponin
Investigation of the coupling asymmetries at double-slit interference experiments
Double-slit experiments inferring the phase and the amplitude of the
transmission coefficient performed at quantum dots (QD), in the Coulomb
blockade regime, present anomalies at the phase changes depending on the number
of electrons confined. This phase change cannot be explained if one neglects
the electron-electron interactions. Here, we present our numerical results,
which simulate the real sample geometry by solving the Poisson equation in 3D.
The screened potential profile is used to obtain energy eigenstates and
eigenvalues of the QD. We find that, certain energy levels are coupled to the
leads stronger compared to others. Our results give strong support to the
phenomenological models in the literature describing the charging of a QD and
the abrupt phase changes.Comment: conference paper, 50th anniversary of Aharonov-Bohm effec
Western Blot Analysis of the IgG-Antibody Response to Acid- Glycine-Extracted Antigens from Campylobacter fetus subsp. fetus and C. jejuni in Naturally Infected Sheep
IgG-antibody response in aborting sheep and in apparently healthy sheep in a flock against acidglycine- extracted antigens from three strains for each C. fetus subsp. fetus and C. jejuni were analysed by Western blot. One strain of C. fetus subsp. fetus was isolated from aborting sheep. Western blot analysis of the sera revealed the presence of IgG antibody binding to the common antigens including proteins with the Mw of 63 kDa and 54 kDa in extracts from both C. fetus subsp. fetus and C. jejuni strains. In addition, IgG antibodies in sera from aborting sheep reacted more strongly with the antigens from C. fetus subsp. fetus strains with Mw of approximately 100, 95 and 86.5 kDa than those of apparently healthy sheep. The binding profile of the antibodies with these antigens appeared to be unique for each C. fetus subsp. fetus strain. On the other hand, IgG antibodies only in sera from aborting sheep recognized strongly the antigens of each C. fetus subsp. fetus strain at the Mw ranged from approximately 26 to 22 kDa. However, the antigenic components between 26 and 22 kDa were not detectable in coomassie blue stained gel and thought to have non-protein nature. These low molecular weight antigens of C. fetus subsp. fetus may be related to a recent infection in aborting sheep. These observations indicate that such speciesspecific antigens or conjugated protein antigens could be used for improving the specificity of the serological tests to detect C. fetus antibodies in sheep sera, and may be the candidates for subunit vaccines against ovine abortion
A Note on Doubly Warped Product Contact CR-Submanifolds in trans-Sasakian Manifolds
Warped product CR-submanifolds in Kaehlerian manifolds were intensively
studied only since 2001 after the impulse given by B.Y. Chen. Immediately
after, another line of research, similar to that concerning Sasakian geometry
as the odd dimensional version of Kaehlerian geometry, was developed, namely
warped product contact CR-submanifolds in Sasakian manifolds. In this note we
proved that there exists no proper doubly warped product contact
CR-submanifolds in trans-Sasakian manifolds.Comment: 5 Latex page
Allelopathic potentials of residues of 6 brassica species on johnsongrass [Sorghum halepense (L.) Pers.]
Johnsongrass ( Sorghum halepense (L.) Pers.) is a troublesome weed species of many crops in Turkey as well as worldwide. Allelopathic potential of residues of some brassica species, which are round white radish (Raphanus sativus L.), garden radish (R. sativus L.), black radish (R. sativus L. var. niger), little radish (R. sativus L. var. radicula, turnip (Brassica campestris L. subsp. rapa) and rapeseed (Brassica napus L. oleifera DC.) on johnsongrass were investigated under both laboratory and field conditions. All species suppressed johnsongrass in field and laboratory conditions. The lowest suppression was from garden radish, which has already been used to control johnsongrass by few farmers in Turkey. It is concluded that the plants studied can be used to control johnsongrass. Higher amount of isothiocyanates (isothiocyanate benzyl, Isothiocyanate allyl) in black radish extract and lower amount of isothiocyanates at garden radish extract were determined. Parallel results for johnsongrass suppression and amount of isothiocyanates show that allelopathy play roles in johnsongrass suppression by brassica species
Fermion Quasi-Spherical Harmonics
Spherical Harmonics, , are derived and presented (in a
Table) for half-odd-integer values of and . These functions are
eigenfunctions of and written as differential operators in the
spherical-polar angles, and . The Fermion Spherical Harmonics
are a new, scalar and angular-coordinate-dependent representation of fermion
spin angular momentum. They have symmetry in the angle , and hence
are not single-valued functions on the Euclidean unit sphere; they are
double-valued functions on the sphere, or alternatively are interpreted as
having a double-sphere as their domain.Comment: 16 pages, 2 Tables. Submitted to J.Phys.
Prevalence and Characteristics of Campylobacter Species Isolated from Gallbladder of Slaughtered Sheep in Van (Eastern) Turkey
To determine the prevalence of campylobacter species in gallbladder of sheep in Van, (Eastern) Turkey, a total of 220 gallbladder samples from healthy slaughtered sheep were examined bacteriologically in October 2000 and 2002. Of the 110 samples examined each year, 27 (24.6%) and 24 (21.8%) campylobacter strains were isolated, respectively. Of the 27 campylobacter strains isolated in the year 2000, 14 (51.9%) were identified as C. jejuni, 7 (25.9%) C. fetus, 3 (11.1%) C. coli and 3 (11.1%) C. lari. Similar results were obtained in the study performed in 2002, but C. lari could not be isolated. Growth and biochemical characteristics of all identified Campylobacter species with some exceptions were typical of each species. Six of 13 examined C. fetus strains grew well at both 25 °C and 42 °C in thioglycollate medium and on blood agar. C. jejuni strains differed from C. coli only by Na-hippurate hydrolysis test. Results of the present study revealed that C. jejuni is the most common campylobacter species isolated from gallbladders of sheep. The thermophilic campylobacters in significant proportions may cause contamination of carcass during slaughter and transmission of the food-borne pathogens to humans
Frequency and temperature dependence of the dielectric and AC electrical conductivity in (Ni/Au)/AlGaN/AIN/GaN heterostructures
Cataloged from PDF version of article.The dielectric properties and AC electrical conductivity (sigma(ac))of the (Ni/Au)/Al(0.22)Ga(0.78)N/AlN/GaN heterostructures, with and without the SiN(x) passivation, have been investigated by capacitance-voltage and conductance-voltage measurements in the wide frequency (5kHz-5 MHz) and temperature (80-400 K) range. The experimental values of the dielectric constant (epsilon'), dielectric loss (epsilon ''), loss tangent (tan delta), sigma(ac) and the real and imaginary part of the electric modulus (M' and M '') were found to be a strong function of frequency and temperature. A decrease in the values of epsilon' and epsilon '' was observed, in which they both showed an increase in frequency and temperature. The values of M' and M '' increase with increasing frequency and temperature. The sigma(ac) increases with increasing frequency, while it decreases with increasing temperature. It can be concluded, therefore, that the interfacial polarization can occur more easily at low frequencies and temperatures with the number of interface states density located at the metal/semiconductor interface. It contributes to the epsilon' and sigma(ac). (C) 2009 Elsevier B.V. All rights reserved
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