Systematic scoping review of factors and measures of rurality: toward the development of a rurality index for health care research in Japan

Background: Rural-urban health care disparities are an important topic in health services research. Hence, developing valid and reliable tools to measure rurality is needed to support high quality research. However, Japan, has no index to measure rurality for health care research. In this study, we conducted a systematic scoping review to identify the important factors and methodological approaches to consider in a rurality index to inform the development of a rurality index for Japan. Methods: For our review, we searched six bibliographic databases (MEDLINE, PubMed, CINAHIL, ERIC, Web of Science and the Grey Literature Report) and official websites of national governments such as Government and Legislative Libraries Online Publications Portal (GALLOP), from 1 January 1989 to 31 December 2018. We extracted relevant variables used in the development of rurality indices, the formulas used to calculate indices, and any measures for reliability and validity of these indices. Results: We identified 17 rurality indices from 7 countries. These indices were primarily developed to assess access to health care or to determine eligibility for incentives for health care providers. Frequently used factors in these indices included population size/density and travel distance/time to emergency care or referral centre. Many indices did not report reliability or validity measures. Conclusions: While the concept of rurality and concerns about barriers to access to care for rural residents is shared by many countries, the operationalization of rurality is highly context-specific, with few universal measures or approaches to constructing a rurality index. The results will be helpful in the development of a rurality index in Japan and in other countries

Q値可変フォトニック結晶ナノビーム共振器の作製と光電子相互作用の制御に関する研究

学位の種別:課程博士University of Tokyo(東京大学

Coherent dynamics amongst ensembles of spatially and spectrally varying emitters in waveguide QED

Spectrally and spatially varying ensembles of emitters embedded into waveguide are ever-present in both well-established and emerging technologies. If control of collective excitations can be attained, a plethora of coherent quantum dynamics and applications may be realized on-chip in the scalable paradigm of waveguide quantum electrodynamics (WQED). Here, we demonstrate how inhomogeneous ensembles embedded into waveguides may be employed as single effective and coherent emitters. The symmetric excitation of localized and mescoscopic ensembles benefit from large collective waveguide coupling, allowing for near-unity and tailorable non-Lorentzian extinction of waveguide photons overcoming large inhomogeneous broadening. As an initial illustration possible in currently existing experiments, we demonstrate the classic recreation of the cavity QED (CQED) paradigm using ensembles of rare-earth ions as coherent mirrors and qubits. This work introduces coherent ensemble dynamics to WQED and extends the realm to spectrally tailorable emitters.Comment: 5 main text pages + 2 appendix pages. Comments welcome

Impedance-matched High-overtone Bulk Acoustic Resonator

A high-overtone bulk acoustic resonator (HBAR), in which a piezoelectric transducer is set on an acoustic cavity, has been attracting attention in both fundamental research and RF applications due to its scalability, high frequency, and high quality factor. The acoustic impedance matching in HBARs is crucial for efficient acoustic power transfer from the piezoelectric transducer to the cavity. However, impedance mismatch remains in most HBARs due to the metal layer insertion between the piezoelectric layer and cavity substrate. In this study, we fabricated a nearly impedance-matched high-quality HBAR using an epitaxial AlN piezoelectric layer directly grown on a conductive SiC cavity substrate with no metal layer insertion. The small impedance mismatch was verified from the variation in the free spectral range (FSR), which is comparable to the best value in previously reported HBARs. The experimentally obtained FSR spectra was greatly reproduced by using the Mason model. Broadband phonon cavity modes up to the K-band (26.5 GHz) were achieved by reducing the thickness of the AlN layer from 800 to 200 nm. The high figure of merit of $f\times\text{Q} \sim 1.3\times 10^{13}\ \textrm{Hz}$ at 10 GHz was also obtained. Our nearly impedance-matched high-quality HBAR will enable the development of RF applications, such as low-phase noise oscillators and acoustic filters, as well as research on high-frequency acoustic systems hybridized with electric, optical, and magnetic systems