Curie temperature enhancement of electron doped Sr2_2FeMoO6_6 perovskites studied by photoemission spectroscopy

We report here on the electronic structure of electron-doped half-metallic ferromagnetic perovskites such Sr$_{2-x}$La$_x$FeMoO$_6$ ($x$=0-0.6) as obtained from high-resolved valence-band photoemission spectroscopy (PES). By comparing the PES spectra with band structure calculations, a distinctive peak at the Fermi level (E$_F$) with predominantly (Fe+Mo) t$_{2g}^\downarrow$ character has been evidenced for all samples, irrespectively of the $x$ values investigated. Moreover, we show that the electron doping due to the La substitution provides selectively delocalized carriers to the t$_{2g}^\downarrow$ metallic spin channel. Consequently, a gradual rising of the density of states at the E$_F$ has been observed as a function of the La doping. By changing the incoming photon energy we have shown that electron doping mainly rises the density of states of Mo parentage. These findings provide fundamental clues for understanding the origin of ferromagnetism in these oxides and shall be of relevance for tailoring oxides having still higher T$_C$

New compound sets identified from high throughput phenotypic screening against three kinetoplastid parasites:an open resource

Using whole-cell phenotypic assays, the GlaxoSmithKline high-throughput screening (HTS) diversity set of 1.8 million compounds was screened against the three kinetoplastids most relevant to human disease, i.e. Leishmania donovani, Trypanosoma cruzi and Trypanosoma brucei. Secondary confirmatory and orthogonal intracellular anti-parasiticidal assays were conducted, and the potential for non-specific cytotoxicity determined. Hit compounds were chemically clustered and triaged for desirable physicochemical properties. The hypothetical biological target space covered by these diversity sets was investigated through bioinformatics methodologies. Consequently, three anti-kinetoplastid chemical boxes of ~200 compounds each were assembled. Functional analyses of these compounds suggest a wide array of potential modes of action against kinetoplastid kinases, proteases and cytochromes as well as potential host–pathogen targets. This is the first published parallel high throughput screening of a pharma compound collection against kinetoplastids. The compound sets are provided as an open resource for future lead discovery programs, and to address important research questions.The support and funding of Tres Cantos Open Lab Foundation is gratefully acknowledgedPeer reviewe

The PKC, HOG and Ca2+ signalling pathways co-ordinately regulate chitin synthesis in Candida albicans

Open Access via PMC2649417Peer reviewedPublisher PD

Clinical impact of acute kidney injury on short- and long-term outcomes after transcatheter aortic valve implantation with the CoreValve prosthesis

AbstractBackgroundAcute kidney injury (AKI) after cardiac surgery is associated with increased mortality, but few data exist on the occurrence and clinical impact of AKI associated with transcatheter aortic valve implantation (TAVI). The objective of this study was to determine the incidence and prognosis of AKI after percutaneous implantation of the CoreValve® (Medtronic, Minneapolis, MN, USA) prosthesis.MethodsA total of 357 patients with severe aortic stenosis and 9 patients with pure native aortic regurgitation were treated with the CoreValve prosthesis. AKI was defined according to Valve Academic Research Consortium criteria as the absolute increase in serum creatinine ≥0.3mg/dl at 72h post percutaneous procedure.ResultsAKI was identified in 58 patients (15.8%), none of whom required renal replacement therapy. In patients with AKI, the mortality at 30 days was 13.5% compared with 1.6% of patients without AKI, [odds ratio (OR)=12.2 (95% CI 3.53–41.9); p<0.001] and total mortality after a mean of 26.2±17 months was 29.3% vs. 14.9% [OR=2.36 (95% CI 1.23–4.51), p=0.008]. In the multivariate analysis, AKI was an independent predictor of cumulative total mortality [hazard ratio=2.151, (95% CI from 1.169 to 3.957), p=0.014].ConclusionsThe deterioration of renal function in patients undergoing TAVI with the CoreValve prosthesis is a serious and frequent complication. The occurrence of AKI was associated with increased early mortality and was also a predictor of worse outcomes in follow-up

The IR Luminosity Functions of Rich Clusters

We present MIPS observations of the cluster A3266. About 100 spectroscopic cluster members have been detected at 24 micron. The IR luminosity function in A3266 is very similar to that in the Coma cluster down to the detection limit L_IR~10^43 ergs/s, suggesting a universal form of the bright end IR LF for local rich clusters with M~10^15 M_sun. The shape of the bright end of the A3266-Coma composite IR LF is not significantly different from that of nearby field galaxies, but the fraction of IR-bright galaxies (SFR > 0.2M_sun/yr) in both clusters increases with cluster-centric radius. The decrease of the blue galaxy fraction toward the high density cores only accounts for part of the trend; the fraction of red galaxies with moderate SFRs (0.2 < SFR < 1 M_sun/yr) also decreases with increasing galaxy density. These results suggest that for the IR bright galaxies, nearby rich clusters are distinguished from the field by a lower star-forming galaxy fraction, but not by a change in L*_IR. The composite IR LF of Coma and A3266 shows strong evolution when compared with the composite IR LF of two z~0.8 clusters, MS 1054 and RX J0152, with L*_IR \propto (1+z)^{3.2+/-0.7},Phi*_IR \propto (1+z)^{1.7+/-1.0}. This L*_IR evolution is indistinguishable from that in the field, and the Phi*_IR evolution is stronger, but still consistent with that in the field. The similarity of the evolution of bright-end IR LF in very different cluster and field environments suggests either this evolution is driven by the mechanism that works in both environments, or clusters continually replenish their star-forming galaxies from the field, yielding an evolution in the IR LF that is similar to the field. The mass-normalized integrated star formation rates (SFRs) of clusters within 0.5R_200 also evolve strongly with redshift, as (1+z)^5.3.Comment: 15 pages, 8 figures, 1 table, accepted by Ap

Newly impaired glucose metabolism and prognosis after percutaneous revascularization

Background: Clinical practice guidelines recommend ad hoc screening of diabetes in patients admitted for macrovascular disease; however, these recommendations are rarely followed in real practice. This study was undertaken to assess whether impaired glucose metabolism, newly diagnosed after percutaneous coronary intervention (PCI) or known diabetes, provides prognostic information. Methods: We studied 374 patients who underwent PCI. An oral glucose tolerance test was carried out in the known non-diabetic patients with fasting glucose &lt; 7 mmol/L. Results: Eighty-one percent of the patients presented impaired glucose metabolism, from which 35.3% were previously diagnosed with diabetics, 21.4% were newly detected diabetics, and 24.3% were pre-diabetics. After a mean follow-up of 35.8 ± 13.4 months, only a known history of diabetes was an independent predictor of revascularization (OR = 2.03, p = 0.025), non-fatal acute myocardial infarction (OR = 2.70, p = 0.029) and readmission due to heart failure during the follow-up (OR = 3.82, p = 0.022). Conclusions: Screening for impaired glucose metabolism after PCI permits the detection of a high proportion of patients with abnormal glucose regulations. However, previously known diabetes remains the only independent predictor of cardiovascular events in the follow-up.

Hsp90 orchestrates transcriptional regulation by Hsf1 and cell wall remodelling by MAPK signalling during thermal adaptation in a pathogenic yeast

Acknowledgments We thank Rebecca Shapiro for creating CaLC1819, CaLC1855 and CaLC1875, Gillian Milne for help with EM, Aaron Mitchell for generously providing the transposon insertion mutant library, Jesus Pla for generously providing the hog1 hst7 mutant, and Cathy Collins for technical assistance.Peer reviewedPublisher PD

The most variable VVV sources: eruptive protostars, dipping giants in the nuclear disc and others

We have performed a comprehensive search of a VISTA Variables in the Via Lactea (VVV) data base of 9.5 yr light curves for variable sources with ΔKs ≥ 4 mag, aiming to provide a large sample of high amplitude eruptive young stellar objects (YSOs) and detect unusual or new types of infrared variable source. We find 222 variable or transient sources in the Galactic bulge and disc, most of which are new discoveries. The sample mainly comprises novae, YSOs, microlensing events, Long Period Variable stars (LPVs), and a few rare or unclassified sources. Additionally, we report the discovery of a significant population of aperiodic late-type giant stars suffering deep extinction events, strongly clustered in the Nuclear Disc of the Milky Way. We suggest that these are metal-rich stars in which radiatively driven mass loss has been enhanced by super-solar metallicity. Among the YSOs, 32/40 appear to be undergoing episodic accretion. Long-lasting YSO eruptions have a typical rise time of ∼2 yr, somewhat slower than the 6–12 month time-scale seen in the few historical events observed on the rise. The outburst durations are usually at least 5 yr, somewhat longer than many lower amplitude VVV events detected previously. The light curves are diverse in nature, suggesting that multiple types of disc instability may occur. Eight long-duration extinction events are seen wherein the YSO dims for a year or more, attributable to inner disc structure. One binary YSO in NGC 6530 displays periodic extinction events (P=59 d) similar to KH 15D