560 research outputs found
Grains and Oilseed Cropland: A Global Perspective
Current tight grain markets have led some commentators to argue that the world is entering a phase of rising food scarcity. The present situation js related to the rise in world consumption, which has tended to outpace production during the 1990s. While most supply shortages were due to weather shocks, the global area planted to grains has decreased from 1,784 million acres in l 980to 1,718 million acres in 1996 (USDA). The question remains, Are there enough land resources available globally to meetfutwe production needs? The combined grains and oilseeds area has, however, increased tWer that same period
In vitro invasion of small-cell lung cancer cell lines correlates with expression of epidermal growth factor receptor.
Formation of metastasis is a multistep process involving attachment to the basement membrane, local proteolysis and migration into surrounding tissues, lymph or bloodstream. In the present study, we have analysed the correlation between in vitro invasion and presence of the epidermal growth factor receptor (EGFR) in a panel of 21 small-cell lung cancer (SCLC) cell lines. We have previously reported that ten of these cell lines expressed EGFR protein detected by radioreceptor and affinity labelling assays. In 11 small-cell lung cancer (SCLC) cell lines, EGFR mRNA was detected by Northern blot analysis. In vitro invasion in a Boyden chamber assay was found in all EGFR-positive cell lines, whereas no invasion was detected in the EGFR-negative cell lines. Quantification of the in vitro invasion in 12 selected SCLC cell lines demonstrated that, in the EGFR-positive cell lines, between 5% and 16% of the cells added to the upper chamber were able to traverse the Matrigel membrane. Expression of several matrix metalloproteases (MMP), of tissue inhibitor of MMP (TIMP) and of cathepsin B was evaluated by immunoprecipitation, Western blot analysis and reverse transcriptase polymerase chain reaction (RT-PCR). However, in vitro invasive SCLC cell lines could not be distinguished from non-invasive cell lines based on the expression pattern of these molecules. In six SCLC cell lines, in vitro invasion was also determined in the presence of the EGFR-neutralizing monoclonal antibody mAb528. The addition of this antibody resulted in a significant reduction of the in vitro invasion in three selected EGFR-positive cell lines. Our results show that only EGFR-positive SCLC cell lines had the in vitro invasive phenotype, and it is therefore suggested that the EGFR might play an important role for the invasion potential of SCLC cell lines
Simultaneous ambient pressure X-ray photoelectron spectroscopy and grazing incidence X-ray scattering in gas environments
We have developed an experimental system to simultaneously observe surface
structure, morphology, composition, chemical state, and chemical activity for
samples in gas phase environments. This is accomplished by simultaneously
measuring X-ray photoelectron spectroscopy (XPS) and grazing incidence X-ray
scattering (GIXS) in gas pressures as high as the multi-Torr regime, while also
recording mass spectrometry. Scattering patterns reflect near-surface sample
structures from the nano- to the meso-scale. The grazing incidence geometry
provides tunable depth sensitivity while scattered X-rays are detected across a
broad range of angles using a newly designed pivoting-UHV-manipulator for
detector positioning. At the same time, XPS and mass spectrometry can be
measured, all from the same sample spot and in ambient conditions. To
demonstrate the capabilities of this system, we measured the chemical state,
composition, and structure of Ag-behenate on a Si(001) wafer in vacuum and in
O atmosphere at various temperatures. These simultaneous structural,
chemical, and gas phase product probes enable detailed insights into the
interplay between structure and chemical state for samples in gas phase
environments. The compact size of our pivoting-UHV-manipulator makes it
possible to retrofit this technique into existing spectroscopic instruments
installed at synchrotron beamlines. Because many synchrotron facilities are
planning or undergoing upgrades to diffraction limited storage rings with
transversely coherent beams, a newly emerging set of coherent X-ray scattering
experiments can greatly benefit from the concepts we present here.Comment: 21 pages, 4 figure
MINERvA neutrino detector response measured with test beam data
The MINERvA collaboration operated a scaled-down replica of the solid
scintillator tracking and sampling calorimeter regions of the MINERvA detector
in a hadron test beam at the Fermilab Test Beam Facility. This article reports
measurements with samples of protons, pions, and electrons from 0.35 to 2.0
GeV/c momentum. The calorimetric response to protons, pions, and electrons are
obtained from these data. A measurement of the parameter in Birks' law and an
estimate of the tracking efficiency are extracted from the proton sample.
Overall the data are well described by a Geant4-based Monte Carlo simulation of
the detector and particle interactions with agreements better than 4%, though
some features of the data are not precisely modeled. These measurements are
used to tune the MINERvA detector simulation and evaluate systematic
uncertainties in support of the MINERvA neutrino cross section measurement
program.Comment: as accepted by NIM
The Rewiring of Ubiquitination Targets in a Pathogenic Yeast Promotes Metabolic Flexibility, Host Colonization and Virulence
Funding: This work was funded by the European Research Council [http://erc.europa.eu/], AJPB (STRIFE Advanced Grant; C-2009-AdG-249793). The work was also supported by: the Wellcome Trust [www.wellcome.ac.uk], AJPB (080088, 097377); the UK Biotechnology and Biological Research Council [www.bbsrc.ac.uk], AJPB (BB/F00513X/1, BB/K017365/1); the CNPq-Brazil [http://cnpq.br], GMA (Science without Borders fellowship 202976/2014-9); and the National Centre for the Replacement, Refinement and Reduction of Animals in Research [www.nc3rs.org.uk], DMM (NC/K000306/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Acknowledgments We thank Dr. Elizabeth Johnson (Mycology Reference Laboratory, Bristol) for providing strains, and the Aberdeen Proteomics facility for the biotyping of S. cerevisiae clinical isolates, and to Euroscarf for providing S. cerevisiae strains and plasmids. We are grateful to our Microscopy Facility in the Institute of Medical Sciences for their expert help with the electron microscopy, and to our friends in the Aberdeen Fungal Group for insightful discussions.Peer reviewedPublisher PD
Influence of Market Type and Time of Purchase on Bacterial Counts and Salmonella and Listeria Prevalence in Whole Chickens in Vietnam
The objective of the current study was to determine the influence of market type and sampling time on Salmonella and Listeria prevalence and bacterial counts of 180 whole chicken carcasses collected from 6 supermarkets (SM), 6 indoor markets (IM), and 6 open markets (OM) in Vietnam, at opening (T0) and 4 h after the opening (T4). Salmonella and Listeria prevalence was at least 25.6% and 42.7%, respectively. Whole birds in IM had greater Salmonella prevalence than birds from both SM and OM by 28.4% and 23.0% (P = 0.006 and 0.022, respectively). Listeria prevalence was lower in whole chickens from SM, at 56.6%, than those in IM and OM (78.6% and 73.2%, P = 0.024 and 0.089, respectively). Whole chicken carcasses had more than 10.1, 7.5, and 9.4 log colony-forming units (CFU)/g of aerobic bacteria, Escherichia coli (E. coli), and coliforms, respectively. Both E. coli and coliform counts were greater in IM than in SM (P = 0.002 and 0.006). However, only E. coli counts differed between SM (7.7 log CFU/g) and OM (8.3 log CFU/g; P = 0.024). These results highlighted high levels of bacteria and high prevalence of Salmonella and Listeria in whole chickens in retail establishments in Vietnam, posing potential food safety and public health risks
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