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The ‘common sense’ memory belief system and its implications
Memory experts, the police, and the public, completed a memory questionnaire containing a series of statements about autobiographical memory. The statements covered issues such as the nature of memory, determinants of accuracy, the relation of emotion and trauma to memory, and respondents indicated their agreement/disagreement with each of the statements. The police and public were found to share a ‘common sense’ memory belief system (CSMBS) in which memories were like videos/photographs, and accuracy was determined by the number of details recalled and also by their vividness. In direct contrast the scientific memory belief system, held by memory researchers, largely based on scientific evidence, was the opposite of the CSMBS and memories were judged to be fragmentary, number of details and their nature did not predict accuracy, and memories and their details could be in error and even false. The problematic nature of the CSBMS, which is pervasive in society, in raising the probability of flawed judgments of memory evidence is considered and, by way of illustration, applied to the (very high) attrition rate in complaints of rape
Proper Orthogonal Decomposition Closure Models For Turbulent Flows: A Numerical Comparison
This paper puts forth two new closure models for the proper orthogonal
decomposition reduced-order modeling of structurally dominated turbulent flows:
the dynamic subgrid-scale model and the variational multiscale model. These
models, which are considered state-of-the-art in large eddy simulation,
together with the mixing length and the Smagorinsky closure models, are tested
in the numerical simulation of a 3D turbulent flow around a circular cylinder
at Re = 1,000. Two criteria are used in judging the performance of the proper
orthogonal decomposition reduced-order models: the kinetic energy spectrum and
the time evolution of the POD coefficients. All the numerical results are
benchmarked against a direct numerical simulation. Based on these numerical
results, we conclude that the dynamic subgrid-scale and the variational
multiscale models perform best.Comment: 28 pages, 6 figure
Structure and function of the type III pullulan hydrolase from Thermococcus kodakarensis
Pullulan-hydrolysing enzymes, more commonly known as debranching enzymes for starch and other polysaccharides, are of great interest and have been widely used in the starch-saccharification industry. Type III pullulan hydrolase from Thermococcus kodakarensis (TK-PUL) possesses both pullulanase and α-amylase activities. Until now, only two enzymes in this class, which are capable of hydrolysing both α-1,4- and α-1,6-glycosidic bonds in pullulan to produce a mixture of maltose, panose and maltotriose, have been described. TK-PUL shows highest activity in the temperature range 95–100°C and has a pH optimum in the range 3.5–4.2. Its unique ability to hydrolyse maltotriose into maltose and glucose has not been reported for other homologous enzymes. The crystal structure of TK-PUL has been determined at a resolution of 2.8 Å and represents the first analysis of a type III pullulan hydrolyse. The structure reveals that the last part of the N-terminal domain and the C-terminal domain are significantly different from homologous structures. In addition, the loop regions at the active-site end of the central catalytic domain are quite different. The enzyme has a well defined calcium-binding site and possesses a rare vicinal disulfide bridge. The thermostability of TK-PUL and its homologues may be attributable to several factors, including the increased content of salt bridges, helical segments, Pro, Arg and Tyr residues and the decreased content of serine
Impact of Scottish smoke-free legislation on smoking quit attempts and prevalence
<p><b>Objectives:</b> In Scotland, legislation was implemented in March 2006 prohibiting smoking in all wholly or partially enclosed public spaces. We investigated the impact on attempts to quit smoking and smoking prevalence.</p>
<p><b>Methods:</b> We performed time series models using Box-Jenkins autoregressive integrated moving averages (ARIMA) on monthly data on the gross ingredient cost of all nicotine replacement therapy (NRT) prescribed in Scotland in 2003–2009, and quarterly data on self-reported smoking prevalence between January 1999 and September 2010 from the Scottish Household Survey.</p>
<p><b>Results:</b> NRT prescription costs were significantly higher than expected over the three months prior to implementation of the legislation. Prescription costs peaked at £1.3 million in March 2006; £292,005.9 (95% CI £260,402.3, £323,609, p<0.001) higher than the monthly norm. Following implementation of the legislation, costs fell exponentially by around 26% per month (95% CI 17%, 35%, p<0.001). Twelve months following implementation, the costs were not significantly different to monthly norms. Smoking prevalence fell by 8.0% overall, from 31.3% in January 1999 to 23.7% in July–September 2010. In the quarter prior to implementation of the legislation, smoking prevalence fell by 1.7% (95% CI 2.4%, 1.0%, p<0.001) more than expected from the underlying trend.</p>
<p><b>Conclusions:</b> Quit attempts increased in the three months leading up to Scotland's smoke-free legislation, resulting in a fall in smoking prevalence. However, neither has been sustained suggesting the need for additional tobacco control measures and ongoing support.</p>
The regulatory subunit of PKA-I remains partially structured and undergoes β-aggregation upon thermal denaturation
Background: The regulatory subunit (R) of cAMP-dependent protein kinase (PKA) is a modular flexible protein that responds with large conformational changes to the binding of the effector cAMP. Considering its highly dynamic nature, the protein is rather stable. We studied the thermal denaturation of full-length RIα and a truncated RIα(92-381) that contains the tandem cyclic nucleotide binding (CNB) domains A and B. Methodology/Principal Findings: As revealed by circular dichroism (CD) and differential scanning calorimetry, both RIα proteins contain significant residual structure in the heat-denatured state. As evidenced by CD, the predominantly α-helical spectrum at 25°C with double negative peaks at 209 and 222 nm changes to a spectrum with a single negative peak at 212-216 nm, characteristic of β-structure. A similar α→β transition occurs at higher temperature in the presence of cAMP. Thioflavin T fluorescence and atomic force microscopy studies support the notion that the structural transition is associated with cross-β-intermolecular aggregation and formation of non-fibrillar oligomers. Conclusions/Significance: Thermal denaturation of RIα leads to partial loss of native packing with exposure of aggregation-prone motifs, such as the B' helices in the phosphate-binding cassettes of both CNB domains. The topology of the β-sandwiches in these domains favors inter-molecular β-aggregation, which is suppressed in the ligand-bound states of RIα under physiological conditions. Moreover, our results reveal that the CNB domains persist as structural cores through heat-denaturation. © 2011 Dao et al
Opening the Door to Policy relevant, Interdisciplinary Research on Land Degradation and Development
Modulation of enhancer looping and differential gene targeting by Epstein-Barr virus transcription factors directs cellular reprogramming
Epstein-Barr virus (EBV) epigenetically reprogrammes B-lymphocytes to drive immortalization and facilitate viral persistence. Host-cell transcription is perturbed principally through the actions of EBV EBNA 2, 3A, 3B and 3C, with cellular genes deregulated by specific combinations of these EBNAs through unknown mechanisms. Comparing human genome binding by these viral transcription factors, we discovered that 25% of binding sites were shared by EBNA 2 and the EBNA 3s and were located predominantly in enhancers. Moreover, 80% of potential EBNA 3A, 3B or 3C target genes were also targeted by EBNA 2, implicating extensive interplay between EBNA 2 and 3 proteins in cellular reprogramming. Investigating shared enhancer sites neighbouring two new targets (WEE1 and CTBP2) we discovered that EBNA 3 proteins repress transcription by modulating enhancer-promoter loop formation to establish repressive chromatin hubs or prevent assembly of active hubs. Re-ChIP analysis revealed that EBNA 2 and 3 proteins do not bind simultaneously at shared sites but compete for binding thereby modulating enhancer-promoter interactions. At an EBNA 3-only intergenic enhancer site between ADAM28 and ADAMDEC1 EBNA 3C was also able to independently direct epigenetic repression of both genes through enhancer-promoter looping. Significantly, studying shared or unique EBNA 3 binding sites at WEE1, CTBP2, ITGAL (LFA-1 alpha chain), BCL2L11 (Bim) and the ADAMs, we also discovered that different sets of EBNA 3 proteins bind regulatory elements in a gene and cell-type specific manner. Binding profiles correlated with the effects of individual EBNA 3 proteins on the expression of these genes, providing a molecular basis for the targeting of different sets of cellular genes by the EBNA 3s. Our results therefore highlight the influence of the genomic and cellular context in determining the specificity of gene deregulation by EBV and provide a paradigm for host-cell reprogramming through modulation of enhancer-promoter interactions by viral transcription factors
Proximate composition and mineral profile of eight different unstudied date (Phoenix dactylifera L.) varieties from Pakistan
With the aim of extending the knowledge on chemical composition of dates (Phoenix dactylifera L.), eight different sun dried date varieties; (1) Daki, (2) Aseel, (3) Coconut, (4) Khuzravi, (5) Halavi, (6) Zahidi, (7) Deglet Noor and (8) Barkavi were examined to determine their proximate composition and mineral profile. All the date varieties were found to be rich in proteins, fiber, carbohydrates and net gross energy (352.329 Kcal/100 g in Aseel to 425.147 Kcal/100 g in Khuzravi) having suitable levels of lipids and low values of ash, moisture and oxalates. Na, K and Li were found as macrominerals whereas Cr, Cu, Ca, Mg, Ni, Zn and Mn were found as microminerals. The results suggest that all the studied dates serve as good source of vital nutrients and can be considered as premium quality having significantly higher energy values than the earlier reported values for dates
Electronic Tuning of Zinc Oxide by Direct Fabrication of Chromium (Cr) incorporated photoanodes for Visible-light driven Water Splitting Applications
This is the final version. Available on open access from Nature Research via the DOI in this recordHerein, we report the synthesis of Cr incorporated ZnO sheets arrays microstructures and construction of photoelectrode through a direct aerosol assisted chemical vapour deposition (AACVD) method. The as-prepared Cr incorporated ZnO microstructures were characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, powdered X-ray spectroscopy, X-ray photoelectron spectroscopy and UV-Vis diffused reflectance spectroscopy. The Cr incorporation in ZnO red shifted the optical band gap of as-prepared photoanodes. The 15% Cr incorporation in ZnO has shown enhanced PEC performance. The AACVD method provides an efficient in situ incorporation approach for the manipulation of morphological aspects, phase purity, and band structure of photoelectrodes for an enhanced PEC performance.Higher Education Commission of PakistanUniversity of Mancheste
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