SILVERRUSH. XI. Constraints on the Lyα Luminosity Function and Cosmic Reionization at z = 7.3 with Subaru/Hyper Suprime-Cam

The Lyα luminosity function (LF) of Lyα emitters (LAEs) has been used to constrain the neutral hydrogen fraction in the intergalactic medium (IGM) and thus the timeline of cosmic reionization. Here we present the results of a new narrowband imaging survey for z = 7.3 LAEs in a large area of ∼3 deg2 with Subaru/Hyper Suprime-Cam. No LAEs are detected down to L Lyα ≃ 1043.2 erg s−1 in an effective cosmic volume of ∼2 × 106 Mpc3, placing an upper limit on the bright part of the z = 7.3 Lyα LF for the first time and confirming a decrease in bright LAEs from z = 7.0. By comparing this upper limit with the Lyα LF in the case of fully ionized IGM, which is predicted using an observed z = 5.7 Lyα LF on the assumption that the intrinsic Lyα LF evolves in the same way as the UV LF, we obtain the relative IGM transmission T Ly α IGM ( 7.3 ) / T Ly α IGM ( 5.7 ) < 0.77 and then the volume-averaged neutral fraction x H I(7.3) > 0.28. Cosmic reionization is thus still ongoing at z = 7.3, consistent with results from other x H I estimation methods. A similar analysis using literature Lyα LFs finds that at z = 6.6 and 7.0, the observed Lyα LF agrees with the predicted one, consistent with full ionization.

Comparison of Narrowband Imaging and White-Light Endoscopy for Diagnosis and Screening of Nasopharyngeal Cancer

Objectives We compared the diagnostic accuracies of narrowband imaging and white-light endoscopy in the detection of nasopharyngeal cancer. Data Sources Six databases (PubMed, Cochrane Database, Embase, Web of Science, SCOPUS, and Google Scholar). Review Methods The 6 databases were thoroughly reviewed by 2 authors (working independently) from their dates of inception to December 2019. Nasopharyngeal mucosal or vascular changes detected by narrowband imaging were compared to those detected by white-light endoscopy. The authors extracted true-positive, true-negative, false-positive, and false-negative parameters for each study. Methodological quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies version 2 tool. The extent of interrater agreement was assessed. Results Eighteen prospective or retrospective studies were included. The diagnostic odds ratio of narrowband imaging was 77.560 (95% confidence interval [CI], 37.424-160.739). The area under the summary receiver operating characteristic curve was 0.926. The sensitivity, specificity, and negative predictive value were 0.871 (95% CI, 0.808-0.915), 0.905 (95% CI, 0.816-0.953), and 0.955 (95% CI, 0.906-0.979), respectively. The correlation between sensitivity and the false-positive rate was 0.284, indicating that heterogeneity was absent. Narrowband imaging exhibited moderate interrater reliability (0.7037; 95% CI, 0.6558-0.746). Subgroup analysis showed that vascular patterns revealed by endoscopy in a screened subgroup were significantly more diagnostically accurate than mucosal patterns used for surveillance of a recurrent cancer subgroup. Conclusions Narrowband imaging exhibits high diagnostic accuracy and should be used in the diagnostic workup of nasopharyngeal cancer. However, further studies are necessary to confirm our results.

Imaging spectropolarimetry for magnetic field diagnostics in solar prominences

Context. Narrowband imaging spectropolarimetry is one of the most powerful tools available to infer information about the intensity and topology of the magnetic fields present in extended plasma structures in the solar atmosphere. Aims. We describe the instrumental set-up and the observing procedure that we have developed and optimized at the Istituto Ricerche Solari Locarno in order to perform imaging spectropolarimetry. A measurement that highlights the potential of the ensuing observations for magnetic field diagnostics in solar prominences is presented. Methods. Monochromatic images of solar prominences were obtained by combining a tunable narrowband filter, based on two Fabry-Perot etalons, with a Czerny-Turner spectrograph. Linear and circular polarization were measured at every pixel of the monochromatic image with the Zurich Imaging Polarimeter, ZIMPOL. A wavelength scan was performed across the profile of the considered spectral line. The HAZEL inversion code was applied to the observed Stokes profiles to infer a series of physical properties of the observed structure. Results. We carried out a spectropolarimetric observation of a prominence, consisting of a set of quasi-monochromatic images across the He I D3 line at 5876 Å in the four Stokes parameters. The map of observed Stokes profiles was inverted with HAZEL, finding magnetic fields with intensities between 15 and 30 G and directed along the spine of the prominence, which is in agreement with the results of previous works.

Narrowband Imaging for p16+ Unknown Primary Squamous Cell Carcinoma Prior to Transoral Robotic Surgery

Our purpose was to assess the potential utility of narrowband imaging (NBI) as a tool in diagnosing and treating unknown primary oropharyngeal squamous cell carcinoma (OPSCC) in patients prior to diagnostic resection with transoral robotic surgery (TORS). Between 2016 and March 2019, 29 patients with carcinoma of unknown primary meeting inclusion criteria were identified and treated with TORS. NBI was used preoperatively in 9 of 29 patients. A suspected tumor site was delineated by NBI in 8 of 9 patients (89%). Of the patients imaged with NBI, 8 of 9 (89%) patients had a pathologically confirmed tumor following TORS, corresponding to the same 8 suspected tumor sites identified with NBI. In contrast, a primary tumor was localized following TORS in 15 of 20 (75%) patients not evaluated with NBI. Thus, we see NBI as a potentially useful tool for the diagnosis and management of p16+ carcinoma of unknown primary. Level of Evidence: IIb