1,460 research outputs found
The isolation of differentially expressed cDNA clones from the filarial nematode <i>Brugia pahangi</i>
A cDNA library constructed from 3 day post-infective L3 of the filarial nematode Brugia pahangi was screened by differential hybridization with cDNA probes prepared from different life-cycle stages. Five cDNA clones hybridizing selectively to the mosquito-derived L3 probe were isolated and characterized. Northern blot analysis of 4 of the clones confirmed that each was most highly expressed in the mosquito-derived L3. The expression of each mRNA during parasite development in the mosquito vector was investigated using RT-PCR, and all were shown to be abundant in the immature L3. Four of the 5 cDNAs cloned coded for structural proteins: 2 cuticular collagens, and the muscle proteins tropomyosin and troponin. Further studies on troponin using an antiserum raised to the recombinant protein demonstrated that the protein, unlike the mRNA, was present in all life-cycle stages examined, while immunogold labelling demonstrated that it was localized to the muscle blocks
Triplet lambs and their dams – a review of current knowledge and management systems
Triplet-bearing ewes and their lambs have the potential to improve flock productivity however, the lack of robust information on optimal nutrition and management is limiting their performance. In comparison to twins, the triplet lamb is; lighter, more metabolically challenged, has lower body temperature, and receives less colostrum and milk which combined results in lower survival rates and weaning weights. While scientifically based management guidelines are available for singletons and twins, guidelines are generally lacking for triplets. Although there is some knowledge on the impacts of nutrition, further studies are required to examine the impacts of varying feeding regimens in pregnancy and lactation, across the body condition range. Characterising the impacts of shelter and other paddock factors, stocking rate, mob size and human intervention would also be of benefit. Future studies must be large enough to allow for evaluation of lamb survival and litter birth weight variation
Minimality of planes in normed spaces
We prove that a region in a two-dimensional affine subspace of a normed space
has the least 2-dimensional Hausdorff measure among all compact surfaces
with the same boundary. Furthermore, the 2-dimensional Hausdorff area density
admits a convex extension to . The proof is based on a (probably)
new inequality for the Euclidean area of a convex centrally-symmetric polygon.Comment: 10 pages, v2: minor changes according to referees' comments, to
appear in GAF
Metabolite changes in blood predict the onset of tuberculosis
Immunogenetics and cellular immunology of bacterial infectious disease
Large Scale Cross-Correlations in Internet Traffic
The Internet is a complex network of interconnected routers and the existence
of collective behavior such as congestion suggests that the correlations
between different connections play a crucial role. It is thus critical to
measure and quantify these correlations. We use methods of random matrix theory
(RMT) to analyze the cross-correlation matrix C of information flow changes of
650 connections between 26 routers of the French scientific network `Renater'.
We find that C has the universal properties of the Gaussian orthogonal ensemble
of random matrices: The distribution of eigenvalues--up to a rescaling which
exhibits a typical correlation time of the order 10 minutes--and the spacing
distribution follow the predictions of RMT. There are some deviations for large
eigenvalues which contain network-specific information and which identify
genuine correlations between connections. The study of the most correlated
connections reveals the existence of `active centers' which are exchanging
information with a large number of routers thereby inducing correlations
between the corresponding connections. These strong correlations could be a
reason for the observed self-similarity in the WWW traffic.Comment: 7 pages, 6 figures, final versio
Coulomb gauge approach to (qqg)over-bar hybrid mesons
An effective Coulomb gauge Hamiltonian, H-eff, is used to calculate the light ( u (u) over barg), strange ( s (s) over barg) and charmed (c (c) over barg) hybrid meson spectra. For the same two parameter H-eff providing glueball masses consistent with lattice results and a good description of the observed u, d, s and c quark mesons, a large-scale variational treatment predicts that the lightest hybrid has J(PC) = 0(++) and mass 2.1 GeV. The lightest exotic 1(-+) state is just above 2.2 GeV, near the upper limit of lattice and flux tube predictions. These theoretical formulations all indicate that the observed 1(-+) pi(1)(1600) and, more clearly, pi(1)(1400) are not hybrid states. The Coulomb gauge approach further predicts that in the strange and charmed sectors, respectively, the ground state hybrids have 1(+-) with masses 2.1 and 3.8 GeV, while the. rst exotic 1( +) states are at 2.4 and 4.0 GeV. Finally, using our hybrid wavefunctions and the Franck-Condon principle, a novel experimental signature is presented to assist heavy hybrid meson searches
The public health and economic benefits of taxing sugar-sweetened beverages
Consumption of sugar-sweetened beverages has increased in recent decades; evidence suggests that consumption of these beverages contributes to obesity and adverse health outcomes. The authors discuss the potential public health and economic benefits of taxing sugar-sweetened beverages
FIELD TOLERANCE OF SELECTED VARIETIES TO AND FUNGICIDE EFFICACY AGAINST ALTERNARIA BLIGHT OF SWEET POTATO
Alternaria blight (AB) of sweet potato ( Ipomoea batatas L. ), caused
by Alternaria spp., was recently reported in South Africa, but is
common in southern and eastern Africa. Elsewhere in the world, AB is
controlled primarily using resistant varieties. Twenty-five sweet
potato varieties/breeding lines, from different origins were assessed
for tolerance to AB. The materials were planted in fields having a
history of AB disease and rated for tolerance based on a General
Disease Index (GDI), with the lowest scores representing tolerance, and
the higher scores representing susceptibility. Variety 199062-1 had the
lowest GDI value, and was the most tolerant to AB; while W119 had the
highest GDI value and was the most susceptible to the disease. Other
varieties/breeding lines showed a variation in GDI values between most
tolerant and most susceptible. Among the fungicides tested under field
conditions, the mixture azoxystrobin-difenoconazole was the most
effective in reducing AB intensity. Fungicides pyraclostrobin-boscalid,
unizeb, azoxystrobin-chlorothalonil and cymoxanil-mancozeb were also
effective against the disease.L\u2019alternariose (AB) de la patate douce ( Ipomoea batatas L. ),
maladie caus\ue9e par Alternaria spp., est une maladie nouvellement
rencontr\ue9e en Afrique du Sud, mais tr\ue8s fr\ue9quemment
rencontr\ue9e dans les pays au Sud et \ue0 l\u2019Est de
l\u2019Afrique. Ailleurs dans le monde, l\u2019utilisation de
vari\ue9t\ue9 r\ue9sistantes est la premi\ue8re mesure de lutte
contre les d\ue9g\ue2ts caus\ue9s par AB. Vingt cinq
vari\ue9t\ue9s de patate douce de diverses origines ont
\ue9t\ue9 \ue9valu\ue9es pour leur sensibilit\ue9 \ue0
l\u2019alternariose. Le mat\ue9riel g\ue9n\ue9tique avait
\ue9t\ue9 plant\ue9 dans des champs ayant une fois infect\ue9s
de AB et class\ue9s tol\ue9rants en fonction de leur index
g\ue9n\ue9ral de la maladie (GDI). Les plus petits scores indiquent
la tolerance, tandis que les scores les plus \ue9lev\ue9s indiquent
la susceptibilit\ue9. La vari\ue9t\ue9 199062-1 avait la plus
petite de GDI et donc \ue9tait le plus tolerant \ue0 AB, tandis que
la vari\ue9t\ue9 W119 pr\ue9sentait la valeur de GDI la plus
\ue9lev\ue9e; par cons\ue9quent \ue9tait la plus susceptible de
toutes les vari\ue9t\ue9s. Les autres vari\ue9t\ue9s
\ue9taient diff\ue9rentes en ce qui concerne leur GDI, les valeurs
de GDI variaient du plus petit au plus grand. Parmi les fongicides
test\ue9s, le m\ue9lange azoxystrobin-difenoconazole \ue9tait le
plus efficace. Les fongicides pyraclostrobin-boscalid, unizeb,
azoxystrobin-chlorothalonil et cymoxanil-mancozeb \ue9taient aussi
efficace contre l\u2019 alternariose
Motion of a driven tracer particle in a one-dimensional symmetric lattice gas
We study the dynamics of a tracer particle subject to a constant driving
force in a one-dimensional lattice gas of hard-core particles whose
transition rates are symmetric. We show that the mean displacement of the
driven tracer grows in time, , as , rather than the linear
time dependence found for driven diffusion in the bath of non-interacting
(ghost) particles. The prefactor is determined implicitly, as the
solution of a transcendental equation, for an arbitrary magnitude of the
driving force and an arbitrary concentration of the lattice gas particles. In
limiting cases the prefactor is obtained explicitly. Analytical predictions are
seen to be in a good agreement with the results of numerical simulations.Comment: 21 pages, LaTeX, 4 Postscript fugures, to be published in Phys. Rev.
E, (01Sep, 1996
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