Future requirements for and supply of ophthalmologists for an aging population in Singapore

#### Background Singapore’s population, as that of many other countries, is aging; this is likely to lead to an increase in eye diseases and the demand for eye care. Since ophthalmologist training is long and expensive, early planning is essential. This paper forecasts workforce and training requirements for Singapore up to the year 2040 under several plausible future scenarios. #### Methods The Singapore Eye Care Workforce Model was created as a continuous time compartment model with explicit workforce stocks using system dynamics. The model has three modules: prevalence of eye disease, demand, and workforce requirements. The model is used to simulate the prevalence of eye diseases, patient visits, and workforce requirements for the public sector under different scenarios in order to determine training requirements. #### Results Four scenarios were constructed. Under the baseline business-as-usual scenario, the required number of ophthalmologists is projected to increase by 117% from 2015 to 2040. Under the current policy scenario (assuming an increase of service uptake due to increased awareness, availability, and accessibility of eye care services), the increase will be 175%, while under the new model of care scenario (considering the additional effect of providing some services by non-ophthalmologists) the increase will only be 150%. The moderated workload scenario (assuming in addition a reduction of the clinical workload) projects an increase in the required number of ophthalmologists of 192% by 2040. Considering the uncertainties in the projected demand for eye care services, under the business-as-usual scenario, a residency intake of 8–22 residents per year is required, 17–21 under the current policy scenario, 14–18 under the new model of care scenario, and, under the moderated workload scenario, an intake of 18–23 residents per year is required. #### Conclusions The results show that under all scenarios considered, Singapore’s aging and growing population will result in an almost doubling of the number of Singaporeans with eye conditions, a significant increase in public sector eye care demand and, consequently, a greater requirement for ophthalmologists

Measurement of νˉμ\bar{\nu}_{\mu} and νμ\nu_{\mu} charged current inclusive cross sections and their ratio with the T2K off-axis near detector

We report a measurement of cross section $\sigma(\nu_{\mu}+{\rm nucleus}\rightarrow\mu^{-}+X)$ and the first measurements of the cross section $\sigma(\bar{\nu}_{\mu}+{\rm nucleus}\rightarrow\mu^{+}+X)$ and their ratio $R(\frac{\sigma(\bar \nu)}{\sigma(\nu)})$ at (anti-)neutrino energies below 1.5 GeV. We determine the single momentum bin cross section measurements, averaged over the T2K $\bar{\nu}/\nu$-flux, for the detector target material (mainly Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory frame kinematics of $\theta_{\mu}$500 MeV/c. The results are $\sigma(\bar{\nu})=\left( 0.900\pm0.029{\rm (stat.)}\pm0.088{\rm (syst.)}\right)\times10^{-39}$ and $\sigma(\nu)=\left( 2.41\ \pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}$in units of cm$^{2}$/nucleon and$R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)= 0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure

Search for Lorentz and CPT violation using sidereal time dependence of neutrino flavor transitions over a short baseline

A class of extensions of the Standard Model allows Lorentz and CPT violations, which can be identified by the observation of sidereal modulations in the neutrino interaction rate. A search for such modulations was performed using the T2K on-axis near detector. Two complementary methods were used in this study, both of which resulted in no evidence of a signal. Limits on associated Lorentz and CPT-violating terms from the Standard Model extension have been derived by taking into account their correlations in this model for the first time. These results imply such symmetry violations are suppressed by a factor of more than 10 20 at the GeV scale

Construction status and prospects of the Hyper-Kamiokande project

The Hyper-Kamiokande project is a 258-kton Water Cherenkov together with a 1.3-MW high-intensity neutrino beam from the Japan Proton Accelerator Research Complex (J-PARC). The inner detector with 186-kton fiducial volume is viewed by 20-inch photomultiplier tubes (PMTs) and multi-PMT modules, and thereby provides state-of-the-art of Cherenkov ring reconstruction with thresholds in the range of few MeVs. The project is expected to lead to precision neutrino oscillation studies, especially neutrino CP violation, nucleon decay searches, and low energy neutrino astronomy. In 2020, the project was officially approved and construction of the far detector was started at Kamioka. In 2021, the excavation of the access tunnel and initial mass production of the newly developed 20-inch PMTs was also started. In this paper, we present a basic overview of the project and the latest updates on the construction status of the project, which is expected to commence operation in 2027

Prospects for neutrino astrophysics with Hyper-Kamiokande

Hyper-Kamiokande is a multi-purpose next generation neutrino experiment. The detector is a two-layered cylindrical shape ultra-pure water tank, with its height of 64 m and diameter of 71 m. The inner detector will be surrounded by tens of thousands of twenty-inch photosensors and multi-PMT modules to detect water Cherenkov radiation due to the charged particles and provide our fiducial volume of 188 kt. This detection technique is established by Kamiokande and Super-Kamiokande. As the successor of these experiments, Hyper-K will be located deep underground, 600 m below Mt. Tochibora at Kamioka in Japan to reduce cosmic-ray backgrounds. Besides our physics program with accelerator neutrino, atmospheric neutrino and proton decay, neutrino astrophysics is an important research topic for Hyper-K. With its fruitful physics research programs, Hyper-K will play a critical role in the next neutrino physics frontier. It will also provide important information via astrophysical neutrino measurements, i.e., solar neutrino, supernova burst neutrinos and supernova relic neutrino. Here, we will discuss the physics potential of Hyper-K neutrino astrophysics

ELECTRON EXCITATION RATES IN NON-MAXWELLIAN PLASMAS

Nous étudions l'excitation collisionnelle relative à des transitions permise et interdites d'ions héliumoïdes dans deux types de plasmas non-Maxwelliens : plasmas présentant une population suprathermique et plasmas ayant une distribution d'électrons en exp-(v/vm)m. Les taux s'avèrent être extrêmement affectés par le caractère non-Maxwellien pour les valeurs moyennes et grandes de χ/kTe (χ : énergie du seuil ). Il faudrait tenir compte de ce fait et éventuellement en tirer partie dans les études de modélisation de l'amplification X réalisées dans de tels milieux.Electron excitation rates relative to allowed and forbidden transitions of He-like ions are evaluated for two current types of non-Maxwellian plasmas : plasmas with a suprathermal population and plasmas with electron distribution functions of the form exp-(v/vm)m. The rates are shown to be strongly affected by the non-Maxwellian character for moderate and large values of the ratio χ/kTe, χ being the threshold energy. This should be taken into account and hopefully taken advantage of when modelling X-ray amplifications in such plasmas

Dispositif d'aspiration pour scie à ruban de menuiserie. YOTA. Dossier technique.

L'INRS a développé un dispositif de captage de déchets pour scie à ruban de menuiserie, sur le principe de l'encoffrement partiel du volant inférieur et de la lame. Ce dossier présente les informations techniques qui permettront aux hygiénistes industriels de réaliser et de mettre en place un tel dispositif

Reducing the radiation dosage in patients with a scoliosis

A significant number of girls develop an adolescent idiopathic scoliosis and require repeated full-length radiographs of the spine. Since Nash's publication in 1979 [16], there has been considerable concern expressed about protecting them from excessive radiation, and particularly from the development of radiation-induced breast tumours. We present a study which compares the differences in radiation dose using different techniques, specifically, the use of a posteroanterior projection, very fast rare earth screens and progressive wedge-shaped filtration. The use of a posteroanterior projection reduced the sternal exposure by 98.9% and the breast skin exposure by 92%. A combination of all three techniques reduced the sternal exposure by 99.5%. We recommend that these should be used routinely to reduce the radiation hazard to children with an adolescent idiopathic scoliosis. © 1989 Springer-Verlag.SCOPUS: ar.jinfo:eu-repo/semantics/publishe