First hospital outbreak of the globally emerging Candida auris in a European hospital

Background: Candida auris is a globally emerging multidrug resistant fungal pathogen causing nosocomial transmission. We report an ongoing outbreak of C. auris in a London cardio-thoracic center between April 2015 and July 2016. This is the first report of C. auris in Europe and the largest outbreak so far. We describe the identification, investigation and implementation of control measures. Methods: Data on C. auris case demographics, environmental screening, implementation of infection prevention/control measures, and antifungal susceptibility of patient isolates were prospectively recorded then analysed retrospectively. Speciation of C. auris was performed by MALDI-TOF and typing of outbreak isolates performed by amplified fragment length polymorphism (AFLP). Results: This report describes an ongoing outbreak of 50 C. auris cases over the first 16 month (April 2015 to July 2016) within a single Hospital Trust in London. A total of 44 % (n = 22/50) patients developed possible or proven C. auris infection with a candidaemia rate of 18 % (n = 9/50). Environmental sampling showed persistent presence of the yeast around bed space areas. Implementation of strict infection and prevention control measures included: isolation of cases and their contacts, wearing of personal protective clothing by health care workers, screening of patients on affected wards, skin decontamination with chlorhexidine, environmental cleaning with chorine based reagents and hydrogen peroxide vapour. Genotyping with AFLP demonstrated that C. auris isolates from the same geographic region clustered. Conclusion: This ongoing outbreak with genotypically closely related C. auris highlights the importance of appropriate species identification and rapid detection of cases in order to contain hospital acquired transmission

Conformal symmetry in non-local field theories

We have shown that a particular class of non-local free field theory has conformal symmetry in arbitrary dimensions. Using the local field theory counterpart of this class, we have found the Noether currents and Ward identities of the translation, rotation and scale symmetries. The operator product expansion of the energy-momentum tensor with quasi-primary fields is also investigated.Comment: 15 pages, V2 (Some references added) V3(published version

Use of a Chirp Waveform in Pulsed Eddy Current Crack Detection

When an electrical conductor containing a surface-breaking crack is subjected to a short pulse of electromagnetic radiation, the reflected field contains transient features related to the depth of the crack. This has been demonstrated in both theoretical calculations [1] and in experiments [2,3] on shallow (0.13 mm to 1.3 mm) slots in a low conductivity titanium alloy. Specifically, these results show that the peak crack signal is delayed in time by an amount proportional to the square of the crack depth, and that the signal decay times also increase with increasing depth

Non-destructive monitoring of viability in an ex vivo organ culture model of osteochondral tissue

Organ culture is an increasingly important tool in research, with advantages over monolayer cell culture due to the inherent natural environment of tissues. Successful organ cultures must retain cell viability. The aim of this study was to produce viable and non-viable osteochondral organ cultures to assess the accumulation of soluble markers in the conditioned medium for predicting tissue viability. Porcine femoral osteochondral plugs were cultured for 20 days, with the addition on day 6, of Triton X-100 (to induce necrosis), camptothecin (to induce apoptosis) or no toxic additives. Tissue viability was assessed by the tissue destructive XTT (sodium 3'-[1-[(phenylamino)-carbonyl]-3,4-tetrazolium]-bis(4-methoxy-6-nitro)benzene-sulfonic acid hydrate) assay method and LIVE/DEAD® staining of the cartilage at days 0, 6 and 20. Tissue structure was assessed by histological evaluation using haematoxylin & eosin and safranin O. Conditioned medium was assessed every 3-4 days for glucose depletion, and levels of lactate dehydrogenase (LDH), alkaline phosphatase (AP), glycosaminoglycans (GAGs), and matrix metalloproteinase (MMP)-2 and MMP-9. Necrotic cultures immediately showed a reduction in glucose consumption, and an immediate increase in LDH, GAG, MMP-2 and MMP-9 levels. Apoptotic cultures showed a delayed reduction in glucose consumption and delayed increase in LDH, a small rise in MMP-2 and MMP-9, but no significant effect on GAGs released into the conditioned medium. The data showed that tissue viability could be monitored by assessing the conditioned medium for the aforementioned markers, negating the need for tissue destructive assays. Physiologically relevant whole- or part-joint organ culture models, necessary for research and pre-clinical assessment of therapies, could be monitored this way, reducing the need to sacrifice tissues to determine viability, and hence reducing the sample numbers necessary

Chaotic genetic patchiness without sweepstakes reproduction in the shore crab Hemigrapsus oregonensis

Fine-scale spatial and temporal variation in the genetic composition of benthic recruits, known as chaotic genetic patchiness, is often observed in marine and estuarine species with planktonic larvae. Several explanations have been proposed for chaotic genetic patchiness, including sweepstakes reproductive success, variability in larval source, and natural selection. In a survey of the green shore crab Hemigrapsus oregonensis in Bodega Bay, California, USA, allele frequencies at a mitochondrial single nucleotide polymorphism were found to differ significantly among samples of first-stage zoeae and between zoeae and adults. Sweepstakes reproductive success is unlikely to be responsible because the fecundity of this species is too low and there was no reduction in genetic diversity among zoeae. In principle, influxes of larvae from genetically distinct populations over 500 km to the north could have caused these differences; however, coalescent estimates indicated that gene flow from these distant populations has been very low and it is unlikely that first-stage zoeae would have been transported such great distances. The possibility remains that natural selection, directly or indirectly, is responsible for the observed patchiness in mitochondrial allele frequencies

A very faint core-collapse supernova in M85

An anomalous transient in the early Hubble-type (S0) galaxy Messier 85 (M85) in the Virgo cluster was discovered by Kulkarni et al. (2007) on 7 January 2006 that had very low luminosity (peak absolute R-band magnitude MR of about -12) that was constant over more than 80 days, red colour and narrow spectral lines, which seem inconsistent with those observed in any known class of transient events. Kulkarni et al. (2007) suggest an exotic stellar merger as the possible origin. An alternative explanation is that the transient in M85 was a type II-plateau supernova of extremely low luminosity, exploding in a lenticular galaxy with residual star-forming activity. This intriguing transient might be the faintest supernova that has ever been discovered.Comment: 7 pages, 2 figures. Submitted to Nature "Brief Communication Arising" on 18 July 2007, Accepted on 17 August 2007. Arising from: Kulkarni et al. 2007, Nature, 447, 458-46

Quantum states made to measure

Recent progress in manipulating quantum states of light and matter brings quantum-enhanced measurements closer to prospective applications. The current challenge is to make quantum metrologic strategies robust against imperfections.Comment: 4 pages, 3 figures, Commentary for Nature Photonic