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Abstract in Undetermined Applications of physical bounds for electromagnetic radiators can be used to derive a priori estimates for antenna parameters in terms of the directivity-bandwidth product. These estimates relate the static electric and magnetic polarizability of the radiating structure to its dynamic properties. The results have previously been illustrated for dipole radiators with good aApplications of physical bounds for electromagnetic radiators can be used to derive a priori estimates for antenna parameters in terms of the directivity-bandwidth product. These estimates relate the static electric and magnetic polarizability of the radiating structure to its dynamic properties. The results have previously been illustrated for dipole radiators with good agreement. Here, the bound

The frequency dependence of the permittivity, permeability, and index of refraction restrict metamaterial applications such as cloaking and perfect lenses. Here, the principles of causality and passivity together with identities for Herglotz functions are used to construct various sum rules. The sum rules relate the frequency dependence of the material parameters with their high- and low-frequency

I denna AMM-rapport presenteras åtgärdsförslag som syftar till att förbättra skolledares arbetsmiljö. Rapporten är en del av forskningsprojektet ”Skolledares arbetsmiljö: Ett projekt om organisatoriska förutsättningar, stressrelaterad psykisk ohälsa, personalrörlighet och förbättringspotential” som finansierats av AFA Försäkring (dnr 170094). Åtgärdsförslagen har samlats in med hjälp av enkäter, g

Colour polymorphisms are popular study systems among biologists interested in evolutionary dynamics, genomics, sexual selection and sexual conflict. In many damselfly groups, such as in the globally distributed genus Ischnura (forktails), sex-limited female colour polymorphisms occur in multiple species. Female-polymorphic species contain two or three female morphs, one of which phenotypically mat

Nitrogenase is the only enzyme that can cleave the triple bond in N2, making nitrogen available to plants (although the enzyme itself is strictly microbial). It has been studied extensively with both experimental and computational methods, but many details of the reaction mechanism are still unclear. X-ray crystallography is the main source of structural information for biomacromolecules, but it h

Global steel production is currently dependent on coal and capital-intensive production facilities with long economic lifetimes. While the Paris Agreement means carbon neutrality must be reached globally by 2050–2070, with negative emissions thereafter, coal-based steel production today accounts for around 8% of global energy-related CO2 emissions. Its production may stabilize or even decline in i

The Nehruvian policies propagated upon India’s independence envisaged no place for religion in political mobilization. Still, religion has continued to affect and influence Indian politics, even as India has become progressively affected by processes of liberalization and globalization. The particular politics of Indian secularism was based on keeping a distance from matters of faith and custom. H

It is increasingly evident that the centre of gravity of international relations is shifting in the direction of Asia. China’s economic and political rise is the single most important dimension of this development. This coincides with fading American hegemony, obvious during, but in essence not limited to, the Trump Presidency. These actor-level changes take place within a context of structural chIt is increasingly evident that the centre of gravity of international relations is shifting in the direction of Asia. China’s economic and political rise is the single most important dimension of this development. This coincides with fading American hegemony, obvious during, but in essence not limited to, the Trump Presidency. These actor-level changes take place within a context of structural ch

Background: The characteristics of Parkinson's disease (PD) include postural instability and resting tremor. However, reductions of tremor amplitude do not always improve postural stability. Research question: What is the effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN) on spectral analysis of body movement in patients with PD when tested without anti-PD medication? The effe

Heparin and heparan sulfate (HS) are linear sulfated disaccharide polymers. Heparin is found mainly in mast cells, while heparan sulfate is found in connective tissue, extracellular matrix and on cell membranes in most tissues. α1-microglobulin (A1M) is a ubiquitous protein with thiol-dependent antioxidant properties, protecting cells and matrix against oxidative damage due to its reductase activi

The geomagnetic dipole moment (GDM) modulates the production rates of cosmogenic radionuclides via the shielding of galactic cosmic rays. Therefore, it is possible to use this linkage to reconstruct past changes in the GDM based on cosmogenic radionuclide records from natural archives such as ice cores. Here we present a GDM reconstruction based on 10Be and 36Cl data from two Greenland ice cores f

The continental silicon (Si) cycle, including terrestrial and freshwater ecosystems (lakes, rivers, estuaries), acts as a filter and modulates the amount of Si transported to the oceans. In order to link the variation in the terrestrial Si cycle to aquatic ecosystems, knowledge on changes in vegetation cover, soil disturbance and the impact of human activity are required. This study on varved lake

Aims: We investigated the risk of latent autoimmune diabetes in adults (LADA) and type 2 diabetes in relation to a healthy lifestyle, the proportion of patients attributable to an unhealthy lifestyle, and the influence of family history of diabetes (FHD) and genetic susceptibility. Methods: The population-based study included incident LADA (n = 571), type 2 diabetes (n = 1962), and matched control

PURPOSE: We evaluated unmet needs of lower urinary tract symptoms-benign prostatic enlargement pharmacological treatment by measuring symptom improvement, persistence and deterioration in real life. A prospective registry was conducted for 24 months in 5 European countries and analyzed by the European Association of Urology Research Foundation. MATERIALS AND METHODS: Previously untreated and treat

As a hypothetical experiment the reaction between carbon monoxide and ethanol to form an ethyl carboxylic acid has been considered. The SET model for catalysis is used. The effect of the catalyst COS on the reactivity of these two species is found to lead to the expected result.

The concept of an innovation system is used to understand how innovation contributes to economic growth. However, innovation systems do not evolve evenly in different parts of the world. This paper contributes to the ongoing debate on the emergence of innovation systems in the context of developing countries. It uses the Rwandan case, where agriculture is a dominant socio-economic sector with high

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Optical nonlinear spectroscopies carry a high amount of information about the systems under investigation; however, as they report polarization signals, the resulting spectra are often congested and difficult to interpret. To recover the landscape of energy states and physical processes such as energy and electron transfer, a clear interpretation of the nonlinear signals is prerequisite. Here, we