494 research outputs found
Quantifying shifts in primary factor demand in the South African economy
This article uses a dynamic CGE model to explain the persistence in the
high levels of unemployment in the South African economy in spite of
modest to relatively strong output growth. We make use of a historical
simulation for the period 2006 to 2013 and find that the capital-labour
ratio increased despite a relative increase in the rental price of capital.
Classical economic theory suggests that changes in industry preferences
toward capital and labour lead to adjusted capital-labour ratios. We
quantify the changes in industry factor preferences during this period and
highlight their impact in explaining observed labour market outcomes.
Other changes in the economy over this period are also quantified.A grant from Economic Research Southern Africa.http://www.tandfonline.com/loi/cdsa202017-08-31hb2017Economic
Experimental Investigation on the Deformation Response of Hybrid 3D Woven Composites
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97059/1/AIAA2012-1572.pd
‘Fit for school’ - a school-based water, sanitation and hygiene programme to improve child health:Results from a longitudinal study in Cambodia, Indonesia and Lao PDR
Effects of heme on the structure of the denatured state and folding kinetics of cytochrome b562
Heme-linked proteins, such as cytochromes, are popular subjects for protein folding studies. There is the underlying question of whether the heme affects the structure of the denatured state by cross-linking it and forming other interactions, which would perturb the folding pathway. We have studied wild-type and mutant cytochrome b562 from Escherichia coli, a 106 residue four-α-helical bundle. The holo protein apparently refolds with a half-life of 4 μs in its ferrous state. We have analysed the folding of the apo protein using continuous-flow fluorescence as well as stopped-flow fluorescence and CD. The apo protein folded much more slowly with a half-life of 270 μs that was unaffected by the presence of exogenous heme. We examined the nature of the denatured states of both holo and apo proteins by NMR methods over a range of concentrations of guanidine hydrochloride. The starting point for folding of the holo protein in concentrations of denaturant around the denaturation transition was a highly ordered native-like species with heme bound. Fully denatured holo protein at higher concentrations of denaturant consisted of denatured apo protein and free heme. Our results suggest that the very fast folding species of denatured holo protein is in a compact state, whereas the normal folding pathway from fully denatured holo protein consists of the slower folding of the apo protein followed by the binding of heme. These data should be considered in the analysis of folding of heme proteins.This work was supported by the BBSRC under the SBDA initiative, the EU TMR Life Sciences programme (contract ERBFMRX-CT-98-0230), the MRC and the NIH (grant GM056250 to H.R.). P.D.B. thanks the BBSRC for an Advanced Research Fellowshi
Imatinib Mesylate: Past Successes and Future Challenges in the Treatment of Gastrointestinal Stromal Tumors
Just over a decade ago, gastrointestinal tumours were a poorly understood mesenchymal neoplasm unsuccessfully treated with chemotherapy. Cytotoxic therapy for advanced disease yielded response rates of 10% and median survival of just 18 months. However, the discovery of KIT and platelet derived growth factor receptor alpha (PDGFRA) mutations as oncogenic drivers of most gastrointestinal tumours, paved the way for targeted therapy. Imatinib mesylate, a tyrosine kinase inhibitor, produces a clinical benefit rate (complete response, partial response, and stable disease) of more than 80% in metastatic setting and a median survival of 57 months. Imatinib is now also approved in adult patients following resection of KIT-positive GIST. Major insights into the mechanism of action of imatinib, unique pharmacokinetics, drug resistance, and management of low grade but chronic adverse effects continue to be made
Supporting users tasks with personal information management and web forms augmentation
Currently, many tasks performed on the Web prompt users to provide personal information through forms. Despite the fact that most users are familiarized with this kind of interaction technique, the use of Web forms is not always straightforward. Indeed, some users might need assistance to understand labels and complex data format required to fill in form fields that, quite often, vary from a Web site to another even when requesting similar data. Filling in forms can be tedious and repetitive as many Web sites request similar information. In this work we analyze user's interactions with Web forms and propose an approach for enhancing Web forms using client-side adaptation techniques in order to assist users to fill in Web forms. As the use of Web forms is closely related to the management of personal information our approach includes the support for data exchange between user's personal information management systems (PIMs) and third-party Web forms. The approach is illustrated by a set of client-side adaptation tools and a pervasive Personal Information Management Systems called PIMI.Publicado en Lecture Notes in Computer Science book series (vol. 7387).Laboratorio de Investigación y Formación en Informática Avanzad
Spatial and temporal modulation of cell instructive cues in a filamentous supramolecular biomaterial
Supramolecular materials provide unique opportunities to mimic both the structure and mechanics of the biopolymer networks that compose the extracellular matrix. However, strategies to modify their filamentous structures in space and time in 3D cell culture to study cell behavior as encountered in development and disease are lacking. We herein disclose a multicomponent squaramide-based supramolecular material whose mechanics and bioactivity can be controlled by light through co-assembly of a 1,2-dithiolane (DT) monomer that forms disulfide cross-links. Remarkably, increases in storage modulus from ∼200 Pa to >10 kPa after stepwise photo-cross-linking can be realized without an initiator while retaining colorlessness and clarity. Moreover, viscoelasticity and plasticity of the supramolecular networks decrease upon photo-irradiation, reducing cellular protrusion formation and motility when performed at the onset of cell culture. When applied during 3D cell culture, force-mediated manipulation is impeded and cells move primarily along earlier formed channels in the materials. Additionally, we show photopatterning of peptide cues in 3D using either a photomask or direct laser writing. We demonstrate that these squaramide-based filamentous materials can be applied to the development of synthetic and biomimetic 3D in vitro cell and disease models, where their secondary cross-linking enables mechanical heterogeneity and shaping at multiple length scales.Toxicolog
Fluid Flow and Defect Formation in the Three-Dimensional Dendritic Structure of Nickel-Based Single Crystals
Search for the standard model Higgs boson decaying to a pair in events with no charged leptons and large missing transverse energy using the full CDF data set
We report on a search for the standard model Higgs boson produced in
association with a vector boson in the full data set of proton-antiproton
collisions at TeV recorded by the CDF II detector at the
Tevatron, corresponding to an integrated luminosity of 9.45 fb. We
consider events having no identified charged lepton, a transverse energy
imbalance, and two or three jets, of which at least one is consistent with
originating from the decay of a quark. We place 95% credibility level upper
limits on the production cross section times standard model branching fraction
for several mass hypotheses between 90 and . For a Higgs
boson mass of , the observed (expected) limit is 6.7
(3.6) times the standard model prediction.Comment: Accepted by Phys. Rev. Let
Search for the standard model Higgs boson decaying to a bb pair in events with one charged lepton and large missing transverse energy using the full CDF data set
We present a search for the standard model Higgs boson produced in
association with a W boson in sqrt(s) = 1.96 TeV p-pbar collision data
collected with the CDF II detector at the Tevatron corresponding to an
integrated luminosity of 9.45 fb-1. In events consistent with the decay of the
Higgs boson to a bottom-quark pair and the W boson to an electron or muon and a
neutrino, we set 95% credibility level upper limits on the WH production cross
section times the H->bb branching ratio as a function of Higgs boson mass. At a
Higgs boson mass of 125 GeV/c2 we observe (expect) a limit of 4.9 (2.8) times
the standard model value.Comment: Submitted to Phys. Rev. Lett (v2 contains clarifications suggested by
PRL
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