Photon number resolution using a time-multiplexed single-photon detector

Photon number resolving detectors are needed for a variety of applications including linear-optics quantum computing. Here we describe the use of time-multiplexing techniques that allows ordinary single photon detectors, such as silicon avalanche photodiodes, to be used as photon number-resolving detectors. The ability of such a detector to correctly measure the number of photons for an incident number state is analyzed. The predicted results for an incident coherent state are found to be in good agreement with the results of a proof-of-principle experimental demonstration.Comment: REVTeX4, 6 pages, 8 eps figures, v2: minor changes, v3: changes in response to referee report, appendix added, 1 reference adde

Gavestinel does not improve outcome after acute intracerebral hemorrhage: an analysis from the GAIN International and GAIN Americas studies

<p><b>Background and Purpose:</b> Glycine Antagonist in Neuroprotection (GAIN) International and GAIN Americas trials were prospectively designed, randomized, placebo-controlled trials of gavestinel, a glycine-site antagonist and putative neuroprotectant drug administered within 6 hours of suspected ischemic or hemorrhagic stroke. Both trials reported that gavestinel was ineffective in ischemic stroke. This analysis reports the results in those with primary intracerebral hemorrhage.</p> <p><b>Methods:</b> The primary hypothesis was that gavestinel treatment did not alter outcome, measured at 3 months by the Barthel Index (BI), from acute intracerebral hemorrhage, based on pooled results from both trials. The BI scores were divided into 3 groups: 95 to 100 (independent), 60 to 90 (assisted independence), and 0 to 55 (dependent) or dead.</p> <p><b>Results:</b> In total, 3450 patients were randomized in GAIN International (N=1804) and GAIN Americas (N=1646). Of these, 571 were ultimately identified to have spontaneous intracerebral hematoma on baseline head computerized tomography scan. The difference in distribution of trichotomized BI scores at 3 months between gavestinel and placebo was not statistically significant (P=0.09). Serious adverse events were reported at similar rates in the 2 treatment groups.</p> <p><b>Conclusions:</b> These observations from the combined GAIN International and GAIN Americas trials suggest that gavestinel is not of substantial benefit or harm to patients with primary intracerebral hemorrhage. These findings are similar to results previously reported in patients with ischemic stroke.</p&gt

Comparison of LOQC C-sign gates with ancilla inefficiency and an improvement to functionality under these conditions

We compare three proposals for non-deterministic C-sign gates implemented using linear optics and conditional measurements with non-ideal ancilla mode production and detection. The simplified KLM gate [Ralph et al, Phys.Rev.A {\bf 65}, 012314 (2001)] appears to be the most resilient under these conditions. We also find that the operation of this gate can be improved by adjusting the beamsplitter ratios to compensate to some extent for the effects of the imperfect ancilla.Comment: to appear in PR

All-Optical Switching Demonstration using Two-Photon Absorption and the Classical Zeno Effect

Low-contrast all-optical Zeno switching has been demonstrated in a silicon nitride microdisk resonator coupled to a hot atomic vapor. The device is based on the suppression of the field build-up within a microcavity due to non-degenerate two-photon absorption. This experiment used one beam in a resonator and one in free-space due to limitations related to device physics. These results suggest that a similar scheme with both beams resonant in the cavity would correspond to input power levels near 20 nW.Comment: 4 pages, 5 figure

Detection of epithelial cancer cells in peripheral blood by reverse transcriptase-polymerase chain reaction.

Circulating cancer cells in the blood play a central role in the metastatic process. Their number can be very small and techniques for their detection need to be both sensitive and specific. Polymerase chain reaction (PCR) has been successfully used to detect small numbers of tumour cells in haematological cancer in which abnormalities in DNA are sufficiently consistent to make this possible. For most solid tumours this not yet feasible. However, we have found that reverse transcriptase (RT)-PRC for tissue-specific gene expression is a useful technique for identifying small numbers of circulating cells in melanoma and neuroblastoma patients. In this report we describe detection of colon carcinoma cells by RT-PCR using CK 20 mRNA as a marker. Unlike other cytokeratin genes examined (CK 8 and CK 19), CK 20 was not transcribed in normal haematopoietic cells. This suggests a role for RT-PCR in the detection of colon carcinoma metastasis in blood and bone marrow, using CK 20 as the target gene. Future analysis of clinical material will determine the clinical significance of this technique

24^{24}Mg(pp, α\alpha)21^{21}Na reaction study for spectroscopy of 21^{21}Na

The $^{24}$Mg($p$, $\alpha$)$^{21}$Na reaction was measured at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to better constrain spins and parities of energy levels in $^{21}$Na for the astrophysically important $^{17}$F($\alpha, p$)$^{20}$Ne reaction rate calculation. 31 MeV proton beams from the 25-MV tandem accelerator and enriched $^{24}$Mg solid targets were used. Recoiling $^{4}$He particles from the $^{24}$Mg($p$, $\alpha$)$^{21}$Na reaction were detected by a highly segmented silicon detector array which measured the yields of $^{4}$He particles over a range of angles simultaneously. A new level at 6661 $\pm$ 5 keV was observed in the present work. The extracted angular distributions for the first four levels of $^{21}$Na and Distorted Wave Born Approximation (DWBA) calculations were compared to verify and extract angular momentum transfer.Comment: 11 pages, 6 figures, proceedings of the 18th International Conference on Accelerators and Beam Utilization (ICABU2014