Surface Raman spectroscopic investigation of pyridine adsorption at platinum electrodes - effects of potential and electrolyte

Surface enhanced Raman spectra of pyridine (Py) at Pt electrodes have been investigated as a function of potential and supporting electrolyte. The results show a large difference from those reported for coinage metal electrodes of Ag, Au and Cu, emphasising the effective involvement of chemical enhancement on Pt surfaces. At very negative (or positive) potentials, Raman spectra show the competitive coadsorption of hydrogen (or oxygen-containing species) with Py, and in acidic solutions, PyH+ ions prefer to dissociate into Py adsorbed on Pt surfaces even in the presence of chloride ions. The differences in the surface bonding strength for Py on Pt and coinage metal electrodes are explained in terms of the different electronic configurations of the metals

Jet production in charged current deep inelastic e⁺p scatteringat HERA

The production rates and substructure of jets have been studied in charged current deep inelastic e⁺p scattering for Q² > 200 GeV² with the ZEUS detector at HERA using an integrated luminosity of 110.5 pb⁻¹. Inclusive jet cross sections are presented for jets with transverse energies E_{T}^{jet} > 5 GeV. Measurements of the mean subjet multiplicity, 〈n_{sbj}〉, of the inclusive jet sample are presented. Predictions based on parton-shower Monte Carlo models and next-to-leading-order QCD calculations are compared to the measurements. The value of α_{s} (M_{z}), determined from 〈n_{sbj}〉 at y_{cut} = 10⁻² for jets with 25 < E_{T}^{jet} < 119 GeV, is α_{s} (M_{z}) = 0.1202 ± 0.0052 (stat.)_{-0.0019}^{+0.0060} (syst.)_{-0.0053}^{+0.0065} (th.). The mean subjet multiplicity as a function of Q² is found to be consistent with that measured in NC DIS

Multijet production in neutral current deep inelastic scattering at HERA and determination of α_{s}

Multijet production rates in neutral current deep inelastic scattering have been measured in the range of exchanged boson virtualities 10 5 GeV and –1 < η_{LAB}^{jet} < 2.5. Next-to-leading-order QCD calculations describe the data well. The value of the strong coupling constant α_{s} (M_{z}), determined from the ratio of the trijet to dijet cross sections, is α_{s} (M_{z}) = 0.1179 ± 0.0013 (stat.)_{-0.0046}^{+0.0028}(exp.)_{-0.0046}^{+0.0028}(th.)

Reliability analysis of the Ahringer Caenorhabditis elegans RNAi feeding library: a guide for genome-wide screens

<p>Abstract</p> <p>Background</p> <p>The Ahringer <it>C. elegans </it>RNAi feeding library prepared by cloning genomic DNA fragments has been widely used in genome-wide analysis of gene function. However, the library has not been thoroughly validated by direct sequencing, and there are potential errors, including: 1) mis-annotation (the clone with the retired gene name should be remapped to the actual target gene); 2) nonspecific PCR amplification; 3) cross-RNAi; 4) mis-operation such as sample loading error, <it>etc</it>.</p> <p>Results</p> <p>Here we performed a reliability analysis on the Ahringer <it>C. elegans </it>RNAi feeding library, which contains 16,256 bacterial strains, using a bioinformatics approach. Results demonstrated that most (98.3%) of the bacterial strains in the library are reliable. However, we also found that 2,851 (17.54%) bacterial strains need to be re-annotated even they are reliable. Most of these bacterial strains are the clones having the retired gene names. Besides, 28 strains are grouped into unreliable category and 226 strains are marginal because of probably expressing unrelated double-stranded RNAs (dsRNAs). The accuracy of the prediction was further confirmed by direct sequencing analysis of 496 bacterial strains. Finally, a freely accessible database named CelRNAi (<url>http://biocompute.bmi.ac.cn/CelRNAi/</url>) was developed as a valuable complement resource for the feeding RNAi library by providing the predicted information on all bacterial strains. Moreover, submission of the direct sequencing result or any other annotations for the bacterial strains to the database are allowed and will be integrated into the CelRNAi database to improve the accuracy of the library. In addition, we provide five candidate primer sets for each of the unreliable and marginal bacterial strains for users to construct an alternative vector for their own RNAi studies.</p> <p>Conclusions</p> <p>Because of the potential unreliability of the Ahringer <it>C. elegans </it>RNAi feeding library, we strongly suggest the user examine the reliability information of the bacterial strains in the CelRNAi database before performing RNAi experiments, as well as the post-RNAi experiment analysis.</p

Prognostic value of electrocardiographic detection of unrecognized myocardial infarction in persons with stable coronary artery disease: data from the Heart and Soul Study

Unrecognized myocardial infarction (MI) carries a poor prognosis in the general population, but its prognostic value is less clear in high-risk patients. We sought to determine whether Q waves on electrocardiogram (ECG), suggestive of unrecognized MI, predict cardiovascular events in patients with stable coronary artery disease (CAD), but without a prior history of MI. We studied 462 patients enrolled in the Heart and Soul Study with stable CAD but without a prior history of MI. All patients had baseline ECGs. The baseline prevalence of unrecognized myocardial infarction was 36%. After a mean of 6.3 years of follow-up, there were a total of 141 cardiovascular events. The presence of Q waves in any ECG lead territory predicted cardiovascular events before (unadjusted HR 1.41, 95% CI 1.01-1.97) and after adjustment for demographics, medical history, diastolic function, and ejection fraction (HR 1.55, 95% CI 1.06-2.26). This association was partly attenuated after adjustment for the presence of inducible ischemia at baseline (HR 1.43, 95% CI 0.96-2.12). When specific territories were analyzed separately, Q waves in anterior leads were predictive of cardiovascular events in both unadjusted and adjusted models (adjusted HR 1.85, 95% CI 1.14-3.00), and this association was partly attenuated after adjustment for inducible ischemia. In conclusion, in patients with CAD but no history of prior MI, the presence of any Q waves or anterior Q waves alone is independently predictive of adverse cardiovascular events

Dinutuximab beta for treating neuroblastoma: an evidence review group and decision support unit perspective of a NICE single technology appraisal

As part of its Single Technology Appraisal (STA) process, the UK National Institute for Health and Care Excellence (NICE) invited the manufacturer (EUSA Pharma) of dinutuximab beta (Qarziba®) to submit evidence of its clinical and cost effectiveness for treating neuroblastoma. The BMJ Technology Assessment Group (BMJ-TAG) was commissioned to act as the Evidence Review Group (ERG), reviewing the submission from the company. The Decision Support Unit (DSU) was commissioned to review additional evidence submitted by the company and to undertake further analyses. This article presents the critical review of the company’s submissions by the ERG and DSU, further analyses undertaken by the DSU, and the outcome of the NICE guidance. The clinical effectiveness for dinutuximab beta was derived from a phase III randomised controlled trial (RCT) that assessed the safety and efficacy of the addition of interleukin (IL)-2 to dinutuximab beta plus isotretinoin. This trial did not inform the relative effectiveness of dinutuximab beta versus isotretinoin alone, which was established practice in the UK for maintenance treatment. In the absence of direct evidence, the company initially conducted a naïve indirect treatment comparison against a historical control, and later performed a matching-adjusted indirect comparison (MAIC) against the isotretinoin arm of an RCT comparing dinutuximab alpha and isotretinoin. The company submitted a partitioned survival analysis model that calculated the incremental cost effectiveness of dinutuximab beta versus isotretinoin. The company’s original incremental cost-effectiveness ratio (ICER) was £22,338 per quality-adjusted life-year (QALY) gained. However, the ERG were concerned that the company’s ICER was not suitable for decision making, and thus carried out initial exploratory analysis as a first step to overcome the naïve estimation of treatment effectiveness in the model. The ERG’s analysis estimated an ICER of £111,858 per QALY gained. In their revised analysis incorporating the MAIC and other changes as requested by the appraisal committee, the company’s ICER was £24,661 per QALY gained. When the DSU incorporated longer-term isotretinoin data and made corrections to the model, the ICER increased to between £62,886 and £87,164 per QALY gained depending on the choice of survival model. A confidential Patient Access Scheme (PAS) decreased the ICERs. The ICERs with the PAS were over £40,000 per QALY gained, but the NICE committee additionally considered the patient population and its size, the disease severity, the potential for significant survival benefit and uncaptured health benefits, and recommended dinutuximab beta as a treatment option, subject to the company providing the agreed discount in the PAS

Does the principle of minimum work apply at the carotid bifurcation: a retrospective cohort study

<p>Abstract</p> <p>Background</p> <p>There is recent interest in the role of carotid bifurcation anatomy, geometry and hemodynamic factors in the pathogenesis of carotid artery atherosclerosis. Certain anatomical and geometric configurations at the carotid bifurcation have been linked to disturbed flow. It has been proposed that vascular dimensions are selected to minimize energy required to maintain blood flow, and that this occurs when an exponent of 3 relates the radii of parent and daughter arteries. We evaluate whether the dimensions of bifurcation of the extracranial carotid artery follow this principle of minimum work.</p> <p>Methods</p> <p>This study involved subjects who had computed tomographic angiography (CTA) at our institution between 2006 and 2007. Radii of the common, internal and external carotid arteries were determined. The exponent was determined for individual bifurcations using numerical methods and for the sample using nonlinear regression.</p> <p>Results</p> <p>Mean age for 45 participants was 56.9 ± 16.5 years with 26 males. Prevalence of vascular risk factors was: hypertension-48%, smoking-23%, diabetes-16.7%, hyperlipidemia-51%, ischemic heart disease-18.7%.</p> <p>The value of the exponent ranged from 1.3 to 1.6, depending on estimation methodology.</p> <p>Conclusions</p> <p>The principle of minimum work (defined by an exponent of 3) may not apply at the carotid bifurcation. Additional factors may play a role in the relationship between the radii of the parent and daughter vessels.</p

The dependence of dijet production on photon virtuality in ep collisions at HERA

The dependence of dijet production on the virtuality of the exchanged photon, Q^2, has been studied by measuring dijet cross sections in the range 0 < Q^2 < 2000 GeV^2 with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb^-1. Dijet cross sections were measured for jets with transverse energy E_T^jet > 7.5 and 6.5 GeV and pseudorapidities in the photon-proton centre-of-mass frame in the range -3 < eta^jet <0. The variable xg^obs, a measure of the photon momentum entering the hard process, was used to enhance the sensitivity of the measurement to the photon structure. The Q^2 dependence of the ratio of low- to high-xg^obs events was measured. Next-to-leading-order QCD predictions were found to generally underestimate the low-xg^obs contribution relative to that at high xg^obs. Monte Carlo models based on leading-logarithmic parton-showers, using a partonic structure for the photon which falls smoothly with increasing Q^2, provide a qualitative description of the data.Comment: 35 pages, 6 eps figures, submitted to Eur.Phys.J.

Beauty photoproduction measured using decays into muons in dijet events in ep collisions at s\sqrt{s}=318 GeV

The photoproduction of beauty quarks in events with two jets and a muon has been measured with the ZEUS detector at HERA using an integrated luminosity of 110 pb$^{- 1}$. The fraction of jets containing b quarks was extracted from the transverse momentum distribution of the muon relative to the closest jet. Differential cross sections for beauty production as a function of the transverse momentum and pseudorapidity of the muon, of the associated jet and of $x_{\gamma}^{jets}$, the fraction of the photon's momentum participating in the hard process, are compared with MC models and QCD predictions made at next-to-leading order. The latter give a good description of the data.Comment: 32 pages, 6 tables, 7 figures Table 6 and Figure 7 revised September 200

Search for a narrow charmed baryonic state decaying to D^*+/- p^-/+ in ep collisions at HERA

A resonance search has been made in the D^*+/- p^-/+ invariant-mass spectrum with the ZEUS detector at HERA using an integrated luminosity of 126 pb^-1. The decay channels D^*+ -> D^0 pi^+_s -> (K^- pi^+) pi^+_s and D^*+ -> D^0 pi^+_s -> (K^- pi^+ pi^+ pi^-) pi^+_s (and the corresponding antiparticle decays) were used to identify D^*+/- mesons. No resonance structure was observed in the D^*+/- p^-/+ mass spectrum from more than 60000 reconstructed D^*+/- mesons. The results are not compatible with a report of the H1 Collaboration of a charmed pentaquark, Theta^0_c.Comment: 22 pages, 7 figures, 1 table; minor text revisions; 2 references adde