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The rural non-farm economy, livelihoods and their diversification: issues and options
The work presented here is based on a review of 55 DFID-financed RNFE and livelihood diversification projects, programmes and research comprising rural household survey and other field-related research projects representing a broad range of methodologies borrowed from economics, sociology and social anthropology
The Imprint of Gravitational Waves on the Cosmic Microwave Background
Long-wavelength gravitational waves can induce significant temperature
anisotropy in the cosmic microwave background. Distinguishing this from
anisotropy induced by energy density fluctuations is critical for testing
inflationary cosmology and theories of large-scale structure formation. We
describe full radiative transport calculations of the two contributions and
show that they differ dramatically at angular scales below a few degrees. We
show how anisotropy experiments probing large- and small-angular scales can
combine to distinguish the imprint due to gravitational waves.Comment: 11 pages, Penn Preprint-UPR-
Video on the semantic web : experiences with media streams
In this paper, we report our experiences with the use of SemanticWeb technology for annotating digital video material.Web technology is used to transform a large, existing video ontology embedded in an annotation tool into a commonly accessible format. The recombination of existing video material is then used as an example application, in which the video metadata enables the retrieval of video footage based on both content descriptions and cinematographic concepts, such as establishing and reaction shots. The paper focuses on the practical issues of porting ontological information to the Semantic Web, the multimedia-specific issues of video annotation, and requirements for Semantic Web query and access patterns. It thereby explicitly aims at providing input to the two new W3C Semantic Web Working Groups (Best Practices and Deployment; Data Access)
Results of the MRI substudy of the intravenous magnesium efficacy in stroke trial
<p><b>Background and Purpose:</b>Although magnesium is neuroprotective in animal stroke models, no clinical benefit was confirmed in the Intravenous Magnesium Efficacy in Stroke (IMAGES) trial of acute stroke patients. The Magnetic
Resonance in IMAGES (MR IMAGES) substudy investigated the effects of magnesium on the imaging surrogate
outcome of infarct growth.</p>
<p><b>Methods:</b> IMAGES trial patients in participating centers were randomized to receive either intravenous magnesium or placebo within 12 hours of stroke onset. Infarct growth was defined as volume difference between baseline diffusion-weighted imaging and day 90 fluid-attenuated inversion recovery image lesions. Patients who died were imputed the largest infarct growth observed.</p>
<p><b>Results:</b> Among the 90 patients included in the primary analysis, there was no difference in infarct growth (median absolute growth, P=0.639; median percentage growth, P=0.616; proportion with any growth, P=0.212) between the
46 treated with magnesium and 44 with placebo. Infarct growth correlated with NIHSS score change from baseline to
day 90. There was a trend showing baseline serum glucose correlated with infarct growth with magnesium treatment,
but not in the placebo group. The mismatch frequency was reduced from 73% to 47% by increasing the mismatch
threshold from >20% to >100% of core volume.</p>
<p><b>Conclusions:</b> Infarct growth, confirmed here as a surrogate for clinical progression, was similar between magnesium and placebo treatment, paralleling the main IMAGES trial clinical outcomes. Glucose was a covariate for infarct growth with magnesium treatment. A more stringent mismatch threshold to define penumbra more appropriately would have
excluded half of the patients in this 12-hour time window stroke study.</p>
Determination of the minimal clinically important difference of the UNC Dry Eye Management Scale
Purpose: To establish an initial estimation of the MCID of the University of North Carolina Dry Eye Management Scale (UNC DEMS) and assess its association with patient perceptions of symptom change. Methods: Thirty-three patients (33.3% men, 67.7% women, mean age 60.5 yrs) with previous DEMS scores were recruited from a UNC ophthalmology clinic in spring 2014. We used anchor-based methods, categorizing important symptom change, to compare the change in the DEMS scores across visits to patient assessments of change; linear regression coefficients estimated the MCID. We correlated clinical assessments, patient perceptions, and DEMS scores. Results: DEMS score changes correlated with global anchors [20.4229 (P = 0.014)]. Unadjusted linear regression yielded a beta coefficient of 20.54 (confidence interval, 20.97 to 20.12, R2 = 0.18, P = 0.014), which estimated the DEMS MCID. Adjusting the regression model for days since the last visit and DEMS score improved the association (beta = 20.56; confidence interval, 20.99 to 20.13; R2 = 0.43; P = 0.013). Descriptive statistics produced an MCID of 1 point. Patients said that 2 points would represent a significant change. The DEMS modestly correlated with the Schirmer test (20.4045, P = 0.0266), Oxford Grading Scheme (+0.3713, P = 0.0364), and tear breakup time (20.3559, P = 0.0456). Conclusions: The UNC DEMS is a valid, responsive patient-reported outcome measure instrument, which is easy to use in the clinic and capable of showing an MCID of 1 point
Shoshonites in southern Tibet record Late Jurassic rifting of a Tethyan intraoceanic island arc
Detailed field mapping combined with a petrologic and geochemical investigation of the Zedong terrane within the Yarlung Tsangpo suture zone provides insights to the evolution of now mostly subducted portions of Tethys during the Late Jurassic. The terrane is dominated by volcanic rocks of shoshonitic affinity, which were erupted in a submarine oceanic island arc setting. The volcanic island arc was built on a basement of oceanic crust, and the shoshonites locally overlie a thin section of pillowed island arc tholeiites and red ribbon-bedded radiolarian cherts. Geochemistry of the shoshonites suggests that their development occurred in a setting analogous to that of Late Miocene to Early Pliocene Fiji and was associated with an arc rifting. We speculate that this event may have been a far-field response to developments associated with Gondwana breakup
Low Ligand Requirement for Deletion and Lack of Synapses in Positive Selection Enforce the Gauntlet of Thymic T Cell Maturation
SummaryImmature double-positive (CD4+CD8+) thymocytes respond to negatively selecting peptide-MHC ligands by forming an immune synapse that sustains contact with the antigen-presenting cell (APC). Using fluorescently labeled peptides, we showed that as few as two agonist ligands could promote APC contact and subsequent apoptosis in reactive thymocytes. Furthermore, we showed that productive signaling for positive selection, as gauged by nuclear translocation of a green fluorescent protein (GFP)-labeled NFATc construct, did not involve formation of a synapse between thymocytes and selecting epithelial cells in reaggregate thymus cultures. Antibody blockade of endogenous positively selecting ligands prevented NFAT nuclear accumulation in such cultures and reversed NFAT accumulation in previously stimulated thymocytes. Together, these data suggest a “gauntlet” model in which thymocytes mature by continually acquiring and reacquiring positively selecting signals without sustained contact with epithelial cells, thereby allowing them to sample many cell surfaces for potentially negatively selecting ligands
The Evolution and Long-Term Results of Laparoscopic Antireflux Surgery for the Treatment of Gastroesophageal Reflux Disease
When carefully performed, laparoscopic antireflux surgery is an effective, durable procedure for the control of gastroesophageal reflux disease
Potato nutritional management changes and challenges into the next century
Plant nutrients are important components of the intensive production
system used for potatoes. Nutrient management practices need to be
improved for sustained and increased productivity. Better mangement decisions
will be made when accurate information is available about (a) crop
residues and rotation effects on nutrient cycling, (b) the nutritional characteristics
and requirements of each variety, (c) bioavailability of nutrients
in soils, and (d) fertilization and tillage effects on nutrient-use efficiencies.
Plant growth and nutrient uptake responses to different nutrient availabilities
must also be understood to maximize growth and nutrient efficiencies.
Diagnostic management techniques for nutrients need to be related
to fundamental chemical and biological processes in the soil and plant system
to be applicable to different environments. This information can then be
packaged with other knowledge into a comprehensive crop management
system. These changes should bring our agronomic practices into better
harmony with the natural processes of the production system, and yet be
responsive to social and environmental concerns, and economic reality
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