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TORCH is a time-of-flight detector designed to perform particle identification over the momentum range 2–10 GeV/ c for a 10 m flight path. The detector exploits prompt Cherenkov light produced by charged particles traversing a quartz plate of 10 mm thickness. Photons are then trapped by total internal reflection and directed onto a detector plane instrumented with customised position-sensitive Micro-Channel Plate Photo-Multiplier Tube (MCP-PMT) detectors. A single-photon timing resolution of 70 ps is targeted to achieve the desired separation of pions and kaons, with an expectation of around 30 detected photons per track. Studies of the performance of a small-scale TORCH demonstrator with a radiator of dimensions 120 × 350 × 10 mm 3 have been performed in two test-beam campaigns during November 2017 and June 2018. Single-photon time resolutions ranging from 104. 3 ps to 114. 8 ps and 83. 8 ps to 112. 7 ps have been achieved for MCP-PMTs with granularity 4 × 64 and 8 × 64 pixels, respectively. Photon yields are measured to be within ∼ 10% and ∼ 30% of simulation, respectively. Finally, the outlook for future work with planned improvements is presented. [ABSTRACT FROM AUTHOR]

The TORCH time-of-flight detector is designed to provide particle identification in the momentum range 2 − 10 GeV∕c over large areas. The detector exploits prompt Cherenkov light produced by charged particles traversing a 10 mm thick quartz plate. The photons propagate via total internal reflection and are focused onto a detector plane comprising position-sensitive Micro-Channel Plate Photo-Multiplier Tubes (MCP-PMT) detectors. The goal is to achieve a single-photon timing resolution of 70 ps , giving a timing precision of 15 ps per charged particle by combining the information from around 30 detected photons. The MCP-PMT detectors have been developed with a commercial partner (Photek Ltd, UK), leading to the delivery of a square tube of active area 53 × 53 mm 2 with a granularity of 8 × 128 pixels equivalent. A large-scale demonstrator of TORCH, having a quartz plate of dimensions 660 × 1250 × 10 mm 3 and read out by a pair of MCP-PMTs with custom readout electronics, has been verified in a test beam campaign at the CERN PS. Preliminary results indicate that the required performance is close to being achieved. The anticipated performance of a full-scale TORCH detector at the LHCb experiment is presented. [ABSTRACT FROM AUTHOR]

TORCH is a time-of-flight detector, designed to provide charged π ∕ K particle identification up to a momentum of 10 GeV/c for a 10 m flight path. To achieve this level of performance, a time resolution of 15 ps per incident particle is required. TORCH uses a plane of quartz of 1 cm thickness as a source of Cherenkov photons, which are then focussed onto square Micro-Channel Plate Photomultipliers (MCP-PMTs) of active area 53 × 53 mm 2 , segmented into 8 × 128 pixels equivalent. A small-scale TORCH demonstrator with a customised MCP-PMT and associated readout electronics has been successfully operated in a 5 GeV/c mixed pion/proton beam at the CERN PS facility. Preliminary results indicate that a single-photon resolution better than 100 ps can be achieved. The expected performance of a full-scale TORCH detector for the Upgrade II of the LHCb experiment is also discussed. [ABSTRACT FROM AUTHOR]

The article presents a study on phytoplasma disease of R. xanthina and the association of 16SrI-D phytoplasma with witches' broom in R. xanthina in China.

Emergent phenomena at polar-nonpolar oxide interfaces have been studied intensely in pursuit of next-generation oxide electronics and spintronics. Here we report the disentanglement of critical thicknesses for electron reconstruction and the emergence of ferromagnetism in polar-mismatched LaMnO3/SrTiO3 (001) heterostructures. Using a combination of element-specific x-ray absorption spectroscopy and dichroism, and first-principles calculations, interfacial electron accumulation, and ferromagnetism have been observed within the polar, antiferromagnetic insulator LaMnO3. Our results show that the critical thickness for the onset of electron accumulation is as thin as 2 unit cells (UC), significantly thinner than the observed critical thickness for ferromagnetism of 5 UC. The absence of ferromagnetism below 5 UC is likely induced by electron overaccumulation. In turn, by controlling the doping of the LaMnO3, we are able to neutralize the excessive electrons from the polar mismatch in ultrathin LaMnO3films and thus enable ferromagnetism in films as thin as 3 UC, extending the limits of our ability to synthesize and tailor emergent phenomena at interfaces and demonstrating manipulation of the electronic and magnetic structures of materials at the shortest length scales. [ABSTRACT FROM AUTHOR]

Timing Of internally Reflected CHerenkov photons (TORCH) is a time-of-flight detector proposed for particle identification at low momentum. Charged particles passing through a plane of quartz produce Cherenkov light, some of which is trapped within the plane by total internal reflection and then emerges at the edges. There the photons are focused onto micro-channel plate photon detectors that register their position and arrival time. This allows reconstructing the photon trajectories in quartz and determining the particle crossing time. Commercial micro-channel plate tubes can achieve the required timing resolution, but their anode spatial segmentation is too coarse, at least in one dimension. In addition, these devices must survive a number of years in a high occupancy environment. Micro-channel plate tubes specifically dedicated to the TORCH are currently being designed, constructed and prototyped in collaboration with industry. In the present paper, results from commercial and dedicated devices are reported. [ABSTRACT FROM AUTHOR]

In the presence of multiple primary users (PUs), the exact outage probability of partial amplify-and-forward (AF) relay selection in the spectrum-sharing relay networks is investigated. To gain more insight, a simple and accurate outage probability approximation is also derived in the high signal-to-noise ratio (SNR) region. It is shown that, at high SNR, the outage probability is affected only by the channel gain ratio between relay-destination links to relay-PU links, regardless of the number of relays. Moreover, when more PUs are present, it causes outage performance degradation on the secondary system. Finally, simulation results are presented to verify the analysis. [ABSTRACT FROM AUTHOR]

The article investigates the effect of interleukin 10 concentration within two weeks in patients with unstable angina in Great Britain. This study found that the admission of simvastatin to patients not only significantly reduces low density lipoprotein cholesterol and CRP concentrations within two weeks, but also dramatically increases the concentration of the anti-inflammatory cytokine interleukin 10.

The article discusses research on zinc oxide/titanium dioxide (ZnO/TiO2) nanocable structured photoelectrodes for cadmium silicon (CdS)/Cd selenium (Se) quantum dot co-sensitized solar cells. It references a study by J. J. Tian and colleagues published in a 2013 issue of "Nanoscale." The researchers obtained a power conversion efficiency of 2.7% in QDSCs with a core-shell structural nanocable photoelectrode.

Study Design: A retrospective comparative study was performed in patients with 3-level cervical spondylotic myelopathy (CSM). Objective: To compare the clinical outcomes, radiological parameters, and complication incidence of 3 reconstructive techniques after the anterior decompression of multilevel CSM. Summary Of Background Data: There has been growing interest in combination of anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) for the treatment of multilevel CSM in recent years. However, the clinical efficacy and radiological outcomes of the hybrid decompression and fusion (HDF) have rarely been investigated. Methods: A total of 180 consecutive patients with 3-level CSM undergoing the anterior decompression and fusion procedures from January 2003 to July 2010 were retrospectively investigated. According to various reconstructive techniques, the patients were divided into 3 groups: HDF, ACDF, and ACCF groups. The clinical effects and improvements of cervical and segmental lordosis in each group were assessed. In addition, the fusion rate, postoperative complications, and radiographical adjacent-level changes regarding each group were also evaluated. Results: No statistical differences in clinical effects, restoration of cervical lordosis, and incidences of postoperative complications were found between the HDF and ACDF groups (P > 0.05). The ACCF group has achieved clinical effects similar to the ACDF or HDF group (P > 0.05), but it had more bleeding, lower fusion rate, and higher incidences of postoperative complications compared with the ACDF or HDF group (P < 0.05). The improvements of the cervical and segmental lordosis in the ACCF group were significantly less than the ACDF or HDF group (P < 0.05). There was no significant difference in radiographical adjacent-level changes among the 3 groups (P > 0.05). Conclusion: The HDF can be considered an effective and safe alternative procedure compared with ACDF in the treatment of the multilevel CSM, and ACCF should be the last option. [ABSTRACT FROM AUTHOR]

Elevated-temperature synthesis has been used to generate side-by-side biaxially structured silicon carbide-silica nanowires. The axial growth direction approaches [311] for nanowires with a high density of microtwins and is [211] for defect-free nanowires. The structure of these nanowires, their cross-sectional shape, and their structural transformation between a biaxial and coaxial configuration have been studied by transmission electron microscopy. The Young's modulus of the biaxially structured nanowires was measured to be 50-70 GPa depending on the size of the nanowire. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]