122 research outputs found
Schematic baryon models, their tight binding description and their microwave realization
A schematic model for baryon excitations is presented in terms of a symmetric
Dirac gyroscope, a relativistic model solvable in closed form, that reduces to
a rotor in the non-relativistic limit. The model is then mapped on a nearest
neighbour tight binding model. In its simplest one-dimensional form this model
yields a finite equidistant spectrum. This is experimentally implemented as a
chain of dielectric resonators under conditions where their coupling is
evanescent and good agreement with the prediction is achieved.Comment: 17 pages, 15 figure
Doorway States and Billiards
Whenever a distinct state is immersed in a sea of complicated and dense
states, the strength of the distinct state, which we refer to as a doorway, is
distributed in their neighboring states. We analyze this mechanism for 2-D
billiards with different geometries. One of them is symmetric and integrable,
another is symmetric but chaotic, and the third has a capricious form. The fact
that the doorway-state mechanism is valid for such highly diverse cases, proves
that it is robust.Comment: 7 pages, 6 figures, Accepted in Proceedings of "Symmetries in
Nature", Symposium in Memoriam Marcos Moshinsk
First experimental realization of the Dirac oscillator
We present the first experimental microwave realization of the
one-dimensional Dirac oscillator, a paradigm in exactly solvable relativistic
systems. The experiment relies on a relation of the Dirac oscillator to a
corresponding tight-binding system. This tight-binding system is implemented as
a microwave system by a chain of coupled dielectric disks, where the coupling
is evanescent and can be adjusted appropriately. The resonances of the finite
microwave system yields the spectrum of the one-dimensional Dirac oscillator
with and without mass term. The flexibility of the experimental set-up allows
the implementation of other one-dimensional Dirac type equations.Comment: 6 figures, 5 page
Do UK universities communicate their brands effectively through their websites?
This paper attempts to explore the effectiveness of UK universities’ websites. The area of branding in higher education has received increasing academic investigation, but little work has researched how universities demonstrate their brand promises through their websites. The quest to differentiate through branding can be challenging in the university context, however. It is argued that those institutions that have a strong distinctive image will be in a better position to face a changing future. Employing a multistage methodology, the web pages of twenty UK universities were investigated by using a combination of content and multivariable analysis. Results indicated ‘traditional values’ such as teaching and research were often well communicated in terms of online brand but ‘emotional values’ like social responsibility and the universities’ environments were less consistently communicated, despite their increased topicality. It is therefore suggested that emotional values may offer a basis for possible future online differentiation
Tracking development assistance for health and for COVID-19 : a review of development assistance, government, out-of-pocket, and other private spending on health for 204 countries and territories, 1990-2050
Background The rapid spread of COVID-19 renewed the focus on how health systems across the globe are financed, especially during public health emergencies. Development assistance is an important source of health financing in many low-income countries, yet little is known about how much of this funding was disbursed for COVID-19. We aimed to put development assistance for health for COVID-19 in the context of broader trends in global health financing, and to estimate total health spending from 1995 to 2050 and development assistance for COVID-19 in 2020. Methods We estimated domestic health spending and development assistance for health to generate total health-sector spending estimates for 204 countries and territories. We leveraged data from the WHO Global Health Expenditure Database to produce estimates of domestic health spending. To generate estimates for development assistance for health, we relied on project-level disbursement data from the major international development agencies' online databases and annual financial statements and reports for information on income sources. To adjust our estimates for 2020 to include disbursements related to COVID-19, we extracted project data on commitments and disbursements from a broader set of databases (because not all of the data sources used to estimate the historical series extend to 2020), including the UN Office of Humanitarian Assistance Financial Tracking Service and the International Aid Transparency Initiative. We reported all the historic and future spending estimates in inflation-adjusted 2020 US per capita, purchasing-power parity-adjusted US8. 8 trillion (95% uncertainty interval [UI] 8.7-8.8) or 40.4 billion (0.5%, 95% UI 0.5-0.5) was development assistance for health provided to low-income and middle-income countries, which made up 24.6% (UI 24.0-25.1) of total spending in low-income countries. We estimate that 13.7 billion was targeted toward the COVID-19 health response. 1.4 billion was repurposed from existing health projects. 2.4 billion (17.9%) was for supply chain and logistics. Only 1519 (1448-1591) per person in 2050, although spending across countries is expected to remain varied. Interpretation Global health spending is expected to continue to grow, but remain unequally distributed between countries. We estimate that development organisations substantially increased the amount of development assistance for health provided in 2020. Continued efforts are needed to raise sufficient resources to mitigate the pandemic for the most vulnerable, and to help curtail the pandemic for all. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe
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