594 research outputs found
Field Application of a Monoclonal Antibody Panel to Differentiate Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Isolates
Porcine reproductive and respiratory syndrome (PRRS) is recognized as the most economically devastating disease of swine throughout the world. Nucleotide sequencing and serological studies have deomnstrated sustantial antigenic variation amoung PRRS virus (PRRSV) isolates (Murtaugh, et al., 1995; Nelson, et al., 1993, 1996). Recently, European-like PRRSV isolates have been identified in the US (Rossow, et al. 2000) and other new, highly virulent PRRSV isolates have appeared and affect sows at all stages of gestation causing mortality of adult pigs as well as young pigs (Epperson et al., 1997). Therefore, it is even more important to control the spread of these new strains. Clinical signs vary between herds, indicating that viruses may differ in pathogenicity. Furthermore, effective use of vaccines and management approaches to control PRRS has not always been successful
First Results from the KMOS Lens-Amplified Spectroscopic Survey (KLASS): Kinematics of Lensed Galaxies at Cosmic Noon
We present the first results of the KMOS Lens-Amplified Spectroscopic Survey
(KLASS), a new ESO Very Large Telescope (VLT) large program, doing multi-object
integral field spectroscopy of galaxies gravitationally lensed behind seven
galaxy clusters selected from the HST Grism Lens-Amplified Survey from Space
(GLASS). Using the power of the cluster magnification we are able to reveal the
kinematic structure of 25 galaxies at , in four
cluster fields, with stellar masses . This sample includes 5 sources at with lower stellar masses
than in any previous kinematic IFU surveys. Our sample displays a diversity in
kinematic structure over this mass and redshift range. The majority of our
kinematically resolved sample is rotationally supported, but with a lower ratio
of rotational velocity to velocity dispersion than in the local universe,
indicating the fraction of dynamically hot disks changes with cosmic time. We
find no galaxies with stellar mass in our sample
display regular ordered rotation. Using the enhanced spatial resolution from
lensing, we resolve a lower number of dispersion dominated systems compared to
field surveys, competitive with findings from surveys using adaptive optics. We
find that the KMOS IFUs recover emission line flux from HST grism-selected
objects more faithfully than slit spectrographs. With artificial slits we
estimate slit spectrographs miss on average 60% of the total flux of emission
lines, which decreases rapidly if the emission line is spatially offset from
the continuum.Comment: Accepted for publication in Ap
Novel Ran-RCC1 inhibitory peptide-loaded nanoparticles have anti-cancer efficacy in vitro and in vivo
YesThe delivery of anticancer agents to their subcellular sites of action is a significant challenge
for effective cancer therapy. Peptides, which are integral to several oncogenic pathways, have
significant potential to be utilised as cancer therapeutics due to their selectivity, high potency
and lack of normal cell toxicity. Novel Ras protein-Regulator of chromosome condensation 1
(Ran-RCC1) inhibitory peptides designed to interact with Ran, a novel therapeutic target in
breast cancer, were delivered by entrapment into polyethylene glycol-poly (lactic-co-glycolic acid)
PEG-PLGA polymeric nanoparticles (NPs). A modified double emulsion solvent evaporation
technique was used to optimise the physicochemical properties of these peptide-loaded biodegradable
NPs. The anti-cancer activity of peptide-loaded NPs was studied in vitro using Ran-expressing
metastatic breast (MDA-MB-231) and lung cancer (A549) cell lines, and in vivo using Solid Ehrlich
Carcinoma-bearing mice. The anti-metastatic activity of peptide-loaded NPs was investigated using
migration, invasion and colony formation assays in vitro. A PEG-PLGA-nanoparticle encapsulating
N-terminal peptide showed a pronounced antitumor and anti-metastatic action in lung and breast
cancer cells in vitro and caused a significant reduction of tumor volume and associated tumor growth
inhibition of breast cancer model in vivo. These findings suggest that the novel inhibitory peptides
encapsulated into PEGylated PLGA NPs are delivered effectively to interact and deactivate Ran.
This novel Ran-targeting peptide construct shows significant potential for therapy of breast cancer
and other cancers mediated by Ran overexpression
An Analytical Assessment of NASA's N+1 Subsonic Fixed Wing Project Noise Goal
The Subsonic Fixed Wing Project of NASA's Fundamental Aeronautics Program has adopted a noise reduction goal for new, subsonic, single-aisle, civil aircraft expected to replace current 737 and A320 airplanes. These so-called 'N+1' aircraft - designated in NASA vernacular as such since they will follow the current, in-service, 'N' airplanes - are hoped to achieve certification noise goal levels of 32 cumulative EPNdB under current Stage 4 noise regulations. A notional, N+1, single-aisle, twinjet transport with ultrahigh bypass ratio turbofan engines is analyzed in this study using NASA software and methods. Several advanced noise-reduction technologies are analytically applied to the propulsion system and airframe. Certification noise levels are predicted and compared with the NASA goal
Consumption of bushmeat around a major mine, and matched communities, in Madagascar
Mining can have serious biodiversity consequences and many mining operations take steps to mitigate their impacts. Evaluating their success poses a significant challenge because appropriate counterfactuals (what would have happened in the absence of the mine) are often unavailable. We aimed to estimate the effects of education and enforcement measures carried out by a large mine in eastern Madagascar on local consumption of illegal bushmeat. We adopt a quasi-experimental approach and use an interview technique designed to reduce sensitivity biases to compare levels of consumption amongst mine employees and people living within the mine�s intervention area with those of statistically matched control groups, and to relate differences to respondents� knowledge of relevant wildlife laws. Consumption was lower, and awareness of the law higher, amongst mine employees and those living in the mine�s intervention area. However caution should be applied in interpreting these results as evidence of the effectiveness of anti-bushmeat efforts by the mine due to potential confounding factors: for example abundance of bushmeat species may vary between the study areas, and our method may not have completely removed the sensitivity of questions about illegal consumption. This illustrates the challenges of evaluating conservation impacts. We highlight the low level of understanding of wildlife laws, including among mine employees, and suggest better communication of these laws, as part of an education programme, could be a useful first step towards reducing illegal hunting
Time-delayed model of immune response in plants
In the studies of plant infections, the plant immune response is known to play an essential role. In this paper we derive and analyse a new mathematical model of plant immune response with particular account for post-transcriptional gene silencing (PTGS). Besides biologically accurate representation of the PTGS dynamics, the model explicitly includes two time delays to represent the maturation time of the growing plant tissue and the non-instantaneous nature of the PTGS. Through analytical and numerical analysis of stability of the steady states of the model we identify parameter regions associated with recovery
and resistant phenotypes, as well as possible chronic infections. Dynamics of the system in these regimes is illustrated by numerical simulations of the model
Higher moments of nucleon spin structure functions in heavy baryon chiral perturbation theory and in a resonance model
The third moment of the twist-3 part of the nucleon spin structure
function is generalized to arbitrary momentum transfer and is
evaluated in heavy baryon chiral perturbation theory (HBChPT) up to order
and in a unitary isobar model (MAID). We show how to link
as well as higher moments of the nucleon spin structure functions
and to nucleon spin polarizabilities. We compare our results with the
most recent experimental data, and find a good description of these available
data within the unitary isobar model. We proceed to extract the twist-4 matrix
element which appears in the suppressed term in the twist
expansion of the spin structure function for proton and neutron.Comment: 30 pages, 7 figure
On the role of the magnetic dipolar interaction in cold and ultracold collisions: Numerical and analytical results for NH() + NH()
We present a detailed analysis of the role of the magnetic dipole-dipole
interaction in cold and ultracold collisions. We focus on collisions between
magnetically trapped NH molecules, but the theory is general for any two
paramagnetic species for which the electronic spin and its space-fixed
projection are (approximately) good quantum numbers. It is shown that dipolar
spin relaxation is directly associated with magnetic-dipole induced avoided
crossings that occur between different adiabatic potential curves. For a given
collision energy and magnetic field strength, the cross-section contributions
from different scattering channels depend strongly on whether or not the
corresponding avoided crossings are energetically accessible. We find that the
crossings become lower in energy as the magnetic field decreases, so that
higher partial-wave scattering becomes increasingly important \textit{below} a
certain magnetic field strength. In addition, we derive analytical
cross-section expressions for dipolar spin relaxation based on the Born
approximation and distorted-wave Born approximation. The validity regions of
these analytical expressions are determined by comparison with the NH + NH
cross sections obtained from full coupled-channel calculations. We find that
the Born approximation is accurate over a wide range of energies and field
strengths, but breaks down at high energies and high magnetic fields. The
analytical distorted-wave Born approximation gives more accurate results in the
case of s-wave scattering, but shows some significant discrepancies for the
higher partial-wave channels. We thus conclude that the Born approximation
gives generally more meaningful results than the distorted-wave Born
approximation at the collision energies and fields considered in this work.Comment: Accepted by Eur. Phys. J. D for publication in Special Issue on Cold
Quantum Matter - Achievements and Prospects (2011
Building capacity for HIV/AIDS program leadership and management in Uganda through mentored Fellowships
Background: Around the world, health professionals and program managers are leading and managing public and private health organizations with little or no formal management and leadership training and experience. Objective: To describe an innovative 2-year, long-term apprenticeship Fellowship training program implemented by Makerere University School of Public Health (MakSPH) to strengthen capacity for leadership and management of HIV/AIDS programs in Uganda. Implementation process: The program, which began in 2002, is a 2-year, full-time, non-degree Fellowship. It is open to Ugandan nationals with postgraduate training in health-related disciplines. Enrolled Fellows are attached to host institutions implementing HIV/AIDS programs and placed under the supervision of host institution and academic mentors. Fellows spend 75% of their apprenticeship at the host institutions while the remaining 25% is dedicated to didactic short courses conducted at MakSPH to enhance their knowledge base. Achievements: Overall, 77 Fellows have been enrolled since 2002. Of the 57 Fellows who were admitted between 2002 and 2008, 94.7% (54) completed the Fellowship successfully and 50 (92.3%) are employed in senior leadership and management positions in Uganda and internationally. Eighty-eight percent of those employed (44/54) work in institutions registered in Uganda, indicating a high level of in-country retention. Nineteen of the 20 Fellows who were admitted between 2009 and 2010 are still undergoing training. A total of 67 institutions have hosted Fellows since 2002. The host institutions have benefited through staff training and technical expertise from the Fellows as well as through grant support to Fellows to develop and implement innovative pilot projects. The success of the program hinges on support from mentors, stakeholder involvement, and the hands-on approach employed in training. Conclusion: The Fellowship Program offers a unique opportunity for hands-on training in HIV/AIDS program leadership and management for both Fellows and host institutions
Cosmic Microwave Background Anisotropies from Scaling Seeds: Global Defect Models
We investigate the global texture model of structure formation in cosmogonies
with non-zero cosmological constant for different values of the Hubble
parameter. We find that the absence of significant acoustic peaks and little
power on large scales are robust predictions of these models. However, from a
careful comparison with data we conclude that at present we cannot safely
reject the model on the grounds of present CMB data. Exclusion by means of
galaxy correlation data requires assumptions on biasing and statistics. New,
very stringent constraints come from peculiar velocities.
Investigating the large-N limit, we argue that our main conclusions apply to
all global O(N) models of structure formation.Comment: LaTeX file with RevTex, 27 pages, 23 eps figs., submitted to Phys.
Rev. D. A version with higher quality images can be found at
http://mykonos.unige.ch/~kunz/download/lam.tar.gz for the LaTeX archive and
at http://mykonos.unige.ch/~kunz/download/lam.ps.gz for the compiled
PostScript fil
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