15,997 research outputs found
A newly discovered population of the critically endangered false limpet Siphonaria compressa Allanson, 1958 (Pulmonata: Siphonariidae), with observations on its reproductive biology
The endangered false limpet, Siphonaria compressa, originally described by Allanson in 1958 from Langebaan Lagoon, Saldanha, has been found living in intertidal eelgrass meadows in the embayment of the Knysna River estuary at Bollard Bay, Leisure Isle, Knysna, South Africa. This represents only the second known site of occurrence of the species. Although classified by the IUCN as critically endangered, the Knysna population is viable.Acrobat Distiller 6.0 (Windows
BCG: Do we have an alternative?
Vaccination is generally used as a form of immunoprophylaxis,
so that administration of the vaccine even a
long. time before exposure to the wild-type infectious
organism should afford protection. Since effector T
and B cells are short-lived, a prime requisite for a
vaccine is to generate immunological memory.1 In the
case organisms such as mycobacteria which are
obligate intracellular pathogens and which elicit
granulomatous tissue reactions, artificial immunisation
with live bacteria is required to induce protection.2,3
The only existing vaccine against tuberculosis is the
BCG (Bacille Calmette - Guerin), an attenuated strain
of M.bovis and it is mandatory or officially recommended
in 182 countries or territories. Under the
Expanded Programme on Immuisation (EPT) started
by the Government of India in 1978, BCG is recommended
to be given to all infants 3-9 months after
birth.
Bactericidal action of pulsed exposure to rifampicin, ethambutol, isoniazid & pyrazinamide on Mycobacterium tuberculosis in vitro
The bactericidal action of pulsed exposure to rifampicin (R), ethambutol (Emb), isoniazid (I) and
pyrazinamide (Z) togcthcr on alternate days (REmbIZ) and as REmb and IZ separately on alternate
days (REmb/IZ) on M.tuberculosis H37Rv, two isolates of M.tuberculosis sensitive to these drugs, as
well as four isolates resistant to one or more drugs, was studied using an in vitro method. The
experimental duration was 6 days. REmbIZ and REmb/IZ appeared to have equally good bactericidal
action on M.tuberculosis strains in the in vitro system. The results suggest that splitting REmbIZ into
REmb and IZ on alternate days in short course chemotherapy regimens for tuberculosis may not affect
the bactericidal action of the regimens
Protective response in guineapigs exposed to Mycobacterium avium intracellulare/ M. scrofulaceum, BCG & south Indian isolates of M. tuberculosis
The protective immunity resulting from exposure to nontuberculous mycobacteria (NTM), BCG and
virulent mycobacteria in different sequences was studied in the guineapig model employing strains
prevalent in the south Indian BCG trial area and time kinetics to observe the immuno-modulation. The
findings suggest that during the early course of challenge infection in guineapigs there was no
interference with the immunity due to BCG, by prior exposure to NTM. In the animals sensitised with
M. avium intracellulare before immunisation, the challenge infection was localised and confined to the
site of inoculation, and only a few organisms reached the spleen.. However, at the later stages of the
infection, as seen by the spleen viable counts at 12 wk, it appeared that the barrier at the localised site of
infection may not be intact in the animals with prior exposure to NTM, and a few organisms disseminate
to the spleen
Gallium Arsenide preparation and QE Lifetime Studies using the ALICE Photocathode Preparation Facility
In recent years, Gallium Arsenide (GaAs) type photocathodes have become
widely used as electron sources in modern Energy Recovery Linac based light
sources such as the Accelerators and Lasers in Combined Experiments (ALICE) at
Daresbury Laboratory and as polarised electron source for the proposed
International Linear Collider (ILC). Once activated to a Low Electron Affinity
(LEA) state and illuminated by a laser, these materials can be used as a
high-brightness source of both polarised and un-polarised electrons. This paper
presents an effective multi-stage preparation procedure including heat
cleaning, atomic hydrogen cleaning and the activation process for a GaAs
photocathode. The stability of quantum efficiency (QE) and lifetime of
activated to LEA state GaAs photocathode have been studied in the ALICE
load-lock photocathode preparation facility which has a base pressure in the
order of 10^-11 mbar. These studies are supported by further experimental
evidence from surface science techniques such as X-ray Photoelectron
Spectroscopy (XPS) to demonstrate the processes at the atomic level.Comment: Presented at First International Particle Accelerator Conference,
IPAC'10, Kyoto, Japan, from 23 to 28 May 201
Observations on the cultivation of M.leprae and M. tuberculosis in medium V and V1
Skin scrapings from five different active sites were collected from 14
leprosy patients and inoculated into medium V. Shin scrapings from three
leprosy patients were inoculated into medium V 1. All the cultures were
incubated at 8-10°C. M. tuberculosis H37Rv, pretreatment isoloates and
streptomycin resistant strains were inoculated into medium V, with and without
antibiotics, and incubated at 8-10°C as well as 37°C. Smears were made from
the M. leprae and M. tuberculosis cultures at 0 hours and at different time
points. The number of bacilli in the smears were counted. There was no
increase in the number of M. leprae or M. tuberculosis in any of the cultures
Gallium Arsenide solar cell radiation damage experiment
Gallium arsenide (GaAs) solar cells for space applications from three different manufactures were irradiated with 10 MeV protons or 1 MeV electrons. The electrical performance of the cells was measured at several fluence levels and compared. Silicon cells were included for reference and comparison. All the GaAs cell types performed similarly throughout the testing and showed a 36 to 56 percent power areal density advantage over the silicon cells. Thinner (8-mil versus 12-mil) GaAs cells provide a significant weight reduction. The use of germanium (Ge) substrates to improve mechanical integrity can be implemented with little impact on end of life performance in a radiation environment
The overlap lattice Dirac operator and dynamical fermions
I show how to avoid a two level nested conjugate gradient procedure in the
context of Hybrid Monte Carlo with the overlap fermionic action. The resulting
procedure is quite similar to Hybrid Monte Carlo with domain wall fermions, but
is more flexible and therefore has some potential worth exploring.Comment: Further expanded version. 12 pages, plain Te
In vitro experiments with centella asiatics - investigation to elucidate the effect of an indigenously prepared powder of this plant on acid fastness and viability of M. tuberculosis
Tk herb Centella asiatica (Linn.).jound throughout India. is acclaimed
'to have medicinal properties and has been used in leprosy patients from very
early times. It is considered that the active compound of this herb, called
JlSiaticoside. probably acts on the waxy covering of M.leprae. The in vitro effect
of an indigenously produced dry powder of Centella asiatica (CA) on the acidIJSt1Iess
and viability of M.tuberculosis was investigated in the present study.
Titt results indicate that CA may not have any direct action on the acidjastness
or viabilty of M.tuberculosis H37Rv in vitro. Further studies using purified
asiaticoside ofthe plant or in vivo studies are required
Modeling hormonal and inflammatory contributions to preterm and term labor using uterine temporal transcriptomics
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