Superconducting single photon detectors integrated with diamond nanophotonic circuits

Photonic quantum technologies promise to repeat the success of integrated nanophotonic circuits in non-classical applications. Using linear optical elements, quantum optical computations can be performed with integrated optical circuits and thus allow for overcoming existing limitations in terms of scalability. Besides passive optical devices for realizing photonic quantum gates, active elements such as single photon sources and single photon detectors are essential ingredients for future optical quantum circuits. Material systems which allow for the monolithic integration of all components are particularly attractive, including III-V semiconductors, silicon and also diamond. Here we demonstrate nanophotonic integrated circuits made from high quality polycrystalline diamond thin films in combination with on-chip single photon detectors. Using superconducting nanowires coupled evanescently to travelling waves we achieve high detection efficiencies up to 66 % combined with low dark count rates and timing resolution of 190 ps. Our devices are fully scalable and hold promise for functional diamond photonic quantum devices.Comment: 28 pages, 5 figure

Integrated analysis of bacterial and microeukaryotic communities from differentially active mud volcanoes in the Gulf of Cadiz

The present study assesses the diversity and composition of sediment bacterial and microeukaryotic communities from deep-sea mud volcanoes (MVs) associated with strike-slip faults in the South-West Iberian Margin (SWIM). We used a 16S/18S rRNA gene based pyrosequencing approach to characterize and correlate the sediment bacterial and microeukaryotic communities from MVs with differing gas seep regimes and from an additional site with no apparent seeping activity. In general, our results showed significant compositional changes of bacterial and microeukaryotic communities in sampling sites with different seepage regimes. Sediment bacterial communities were enriched with Methylococcales (putative methanotrophs) but had lower abundances of Rhodospirillales, Nitrospirales and SAR202 in the more active MVs. Within microeukaryotic communities, members of the Lobosa (lobose amoebae) were enriched in more active MVs. We also showed a strong correlation between Methylococcales populations and lobose amoeba in active MVs. This study provides baseline information on the diversity and composition of bacterial and microeukaryotic communities in deep-sea MVs associated with strike-slip faults

Expression of nm23 gene in gastric cancer is associated with a poor 5-year survival

The nm23 gene is thought to play a role as an inhibitor of metastatic progression in several human cancers and its down-regulation has been associated with increased metastasis and reduced survival in some studies, though not in others. To better investigate the role of nm23 in gastric cancer (GC), the expression and prognostic impact of this gene was examined in 107 radically operated GC patients in a high risk area. The expression of nm23 was determined immunohistochemically by using the rabbit antibody anti-human nm23 protein. The expression of nm23 was detected in 40.2% (n = 43) of 107 gastric tumours and correlated with a poorer clinical outcome. In a survival analysis at 5 years, patients with nm23-positive tumours had significantly worse prognosis than patients (n = 64) with nm23-negative tumours (p < 0.05). The prognostic significance of nm23 expression was confirmed by multivariate analysis including terms for tumour stage and lymph node involvement. Our results suggest that the expression of the nm23 gene in gastric carcinoma is significantly related to tumour progression and poor prognosis at 5 years