Evanescent field sensing of moving free-electrons based on optical fibre probe tips

We use tapered optical fiber tips functionalized with plasmonic and metamaterial nanostructures to detect, amplify and control the evanescent electromagnetic field of moving free electrons in the UV-visible spectral range

The hotel industry’s responses to COVID-19: Insight from hybrid thematic analysis and experimental research

Although the travel and tourism industry has been decimated by the COVID-19 pandemic, little research has empirically examined the types and effectiveness of the hotel’s industry’s responses. To examine common response strategies within the hotel industry and assess their effectiveness, two studies were conducted. Study 1 included a hybrid approach involving deductive and inductive thematic analyses to evaluate a large volume of news articles. Five broad themes emerged: revenue management, crisis communication, alternative approaches to service delivery, human resource management, and corporate social responsibility. Drawing upon protection motivation theory, Study 2 involved a pre-test, pilot study, and main experimental study to investigate the effectiveness of three customer-oriented response strategies. Results showed that reassuring crisis communication and contactless services can foster consumer confidence and response efficacy, leading to positive customer attitudes and booking intentions. Crisis communication and price discount were found to influence consumers’ attitudes and booking intentions directly

Electron-beam-driven metasurface holographic light sources

We apply holographic principles to tailor light emission resulting from the injection of free electrons into a nanostructured surface and demonstrate robust control over the direction, divergence wavelength and topological charge of radiation emission

Metasurface holographic light sources driven by electron beam

We apply holographic principles to tailor light emission resulting from the injection of free electrons into a nanostructured surface and demonstrate robust control over the direction, divergence wavelength and topological charge of radiation emission

The Mediating Effects of Tolerance on Residents’ Support Toward Tourism Events

The classic social exchange theory associates residents’ level of support toward tourism events with their perceived positive and negative tourism impacts directly. However, the contradictory results reported in the literature suggest that such conceptualization may not fully capture the dynamics of the underlying relationships because the linkages between perceived costs and support are often vague. The purpose of this study is to introduce and investigate the role of tolerance in the formation of residents’ support toward tourism events. Results based on data collected from 296 residents at 6 different tourism events in a southeast capital city indicated that tolerance significantly mediated the relationship between perceived benefits and support, as well as perceived costs and support. Our study provides strong theoretical support and empirical findings for the inclusion of tolerance in evaluating residents’ support toward tourism events

Holographic free-electron light source

Recent advances in the physics and technology of light generation via free-electron proximity and impact interactions with nanostructures (gratings, photonic crystals, nano-undulators, metamaterials and antenna arrays) have enabled the development of nanoscale-resolution techniques for such applications as mapping plasmons, studying nanoparticle structural transformations and characterizing luminescent materials (including time-resolved measurements). Here, we introduce a universal approach allowing generation of light with prescribed wavelength, direction, divergence and topological charge via point-excitation of holographic plasmonic metasurfaces. It is illustrated using medium-energy free-electron injection to generate highly-directional visible to near-infrared light beams, at selected wavelengths in prescribed azimuthal and polar directions, with brightness two orders of magnitude higher than that from an unstructured surface, and vortex beams with topological charge up to ten. Such emitters, with micron-scale dimensions and the freedom to fully control radiation parameters, offer novel applications in nano-spectroscopy, nano-chemistry and sensing

Utility of clinical features with fine needle aspiration biopsy for diagnosis of Warthin tumor.

BACKGROUND:Conservative management of Warthin tumor (WT) may be a viable alternative to surgery, but there are concerns of missed malignancies on fine needle aspiration biopsy (FNAB). The purpose of this study is to measure the sensitivity and positive predictive value of FNAB for WT, and to identify clinical features associated with WT that can aid in this diagnosis. METHODS: Retrospective analysis of patients from January 1, 2006 to April 30, 2017 at a tertiary care center in London, Ontario, Canada. All patients with a diagnosis of WT on FNAB or resection were included. Electronic medical records were identified for 177 patients that fit the criteria. Study outcomes included the sensitivity and positive predictive value of FNAB alone for WT, and, when including clinical features associated with WT. RESULTS: The mean age of patients in this study was 63.2 years (SD 10.4); 115 (65%) were male, and 157 (89%) were past or present smokers. The measured sensitivity and positive predictive value of FNAB for WT were 95.8 and 97.2% respectively. Two cases were classified as WT on FNAB but confirmed at resection as mucoepidermoid carcinoma and acinic cell carcinoma. When only patients with multifocal, bilateral or incidental tumors were assessed, sensitivities and positive predictive values for each were 100%. Isolating for inferior pole location also resulted in a positive predictive value of 100%. CONCLUSIONS: The sensitivity and positive predictive value of FNAB for WT in this study are high, with two false negatives on FNAB. Multifocal, bilateral, incidentaloma and inferior pole location were identified as potential clinical features that may increase the diagnostic confidence for WT, strengthening the argument for conservative management in these patients. Overall, this study serves as an initial exploration into whether clinical features may be included with FNAB results to improve the sensitivity and positive predictive value of diagnosing WT. Further research is necessary before these findings can be translated into clinical practice

Systematic Review and Meta-Analysis of Screening Tools for Language Disorder

Language disorder is one of the most prevalent developmental disorders and is associated with long-term sequelae. However, routine screening is still controversial and is not universally part of early childhood health surveillance. Evidence concerning the detection accuracy, benefits, and harms of screening for language disorders remains inadequate, as shown in a previous review. In October 2020, a systematic review was conducted to investigate the accuracy of available screening tools and the potential sources of variability. A literature search was conducted using CINAHL Plus, ComDisCome, PsycInfo, PsycArticles, ERIC, PubMed, Web of Science, and Scopus. Studies describing, developing, or validating screening tools for language disorder under the age of 6 were included. QUADAS-2 was used to evaluate risk of bias in individual studies. Meta-analyses were performed on the reported accuracy of the screening tools examined. The performance of the screening tools was explored by plotting hierarchical summary receiver operating characteristic (HSROC) curves. The effects of the proxy used in defining language disorders, the test administrators, the screening-diagnosis interval and age of screening on screening accuracy were investigated by meta-regression. Of the 2,366 articles located, 47 studies involving 67 screening tools were included. About one-third of the tests (35.4%) achieved at least fair accuracy, while only a small proportion (13.8%) achieved good accuracy. HSROC curves revealed a remarkable variation in sensitivity and specificity for the three major types of screening, which used the child's actual language ability, clinical markers, and both as the proxy, respectively. None of these three types of screening tools achieved good accuracy. Meta-regression showed that tools using the child's actual language as the proxy demonstrated better sensitivity than that of clinical markers. Tools using long screening-diagnosis intervals had a lower sensitivity than those using short screening-diagnosis intervals. Parent report showed a level of accuracy comparable to that of those administered by trained examiners. Screening tools used under and above 4yo appeared to have similar sensitivity and specificity. In conclusion, there are still gaps between the available screening tools for language disorders and the adoption of these tools in population screening. Future tool development can focus on maximizing accuracy and identifying metrics that are sensitive to the dynamic nature of language development.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?RecordID=210505, PROSPERO: CRD42020210505