Resonant tunnelling diode based high speed optoelectronic transmitters

Resonant tunneling diode (RTD) integration with photo detector (PD) from epi-layer design shows great potential for combining terahertz (THz) RTD electronic source with high speed optical modulation. With an optimized layer structure, the RTD-PD presented in the paper shows high stationary responsivity of 5 A/W at 1310 nm wavelength. High power microwave/mm-wave RTD-PD optoelectronic oscillators are proposed. The circuitry employs two RTD-PD devices in parallel. The oscillation frequencies range from 20-44 GHz with maximum attainable power about 1 mW at 34/37/44GHz.European Commission [645369

Resonant tunneling diode oscillators for optical communications

The ability to use resonant tunneling diodes (RTDs) as both transmitters and receivers is an emerging topic, especially with regards to wireless communications. Successful data transmission has been achieved using electronic RTDs with carrier frequencies exceeding 0.3 THz. Specific optical-based RTDs, which act as photodetectors, have been developed by adjusting the device structure to include a light absorption layer and small optical windows on top of the device to allow direct optical access. This also allows the optical signal to directly modulate the RTD oscillation. Both types of RTD oscillators will allow for seamless integration of high frequency radio and optical fiber networks.European Union's Horizon research and innovation programme [645369

SAPHO: has the time come for tailored therapy?

SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) syndrome is a heterogeneous condition combining osteoarticular and cutaneous manifestations. Conventional treatments are mostly ineffective. We hereby report two patients, the first with an aggressive form of disease and the second with an incomplete response to two different anti-TNF-α agents. Both were successfully treated with tocilizumab and ustekinumab, respectively, over a long period of time. A narrative review of a biological therapy in SAPHO syndrome yielded very little information on the specific use of these agents. We highlight the advantages of personalising therapy and describe emerging promising treatments for this disease.info:eu-repo/semantics/publishedVersio

Shrinkage properties of plain and recycled steel–fibre-reinforced rapid hardening mortars for repairs

This article investigates the time dependent transport properties and shrinkage performance of rapid hardening plain and fibre reinforced mortars for repair applications. Two plain and two SFRC mixes with 45 kg/m3 of recycled clean steel fibres made with rapid hardening cements (CSA – calcium sulfoaluminate cement and RSC – calcium aluminate cement) are studied. It is found that mixes with CSA cement have much lower shrinkage values (around 220 and 365 microstrains) compared to mixes with RSC cement (around 2690 and 2530 microstrains), but most of the shrinkage in these mixes is autogenous. Nonetheless, fibres reduce the drying shrinkage of RSC cement mixes by approximately 12%. Model code 2010 and ACI equations can be used to estimate the shrinkage development with time for these mixes provided suitable parameters for each cement type are adopted. Inverse analysis using finite element method is successfully employed to determine the moisture diffusivity and the hygral contraction coefficient of each mix. A comparison is made between the values of shrinkage strain predicted by the numerical models over time, for different depths, and code equations. A simple analytical procedure is used to assess cracking and/or delamination risks due to restrained shrinkage for these materials in overlay applications

The impacts of geopolitical risks on the energy sector: Micro-level operative analysis in the European Union

Energy prices play a crucial role in combating geopolitical risks, especially for the major suppliers of energy resources. However, energy prices display a bilateral relationship with geopolitical risks in any economy. Any hike in the price of energy stimulates geopolitical risk factors and visa-versa. The consequences adversely impact economies and bring forth international tensions. This paper bridges a gap between the influence of geopolitical risks relating to energy and international tensions by analyzing micro-level operational measures. We deploy an empirical model to predict the energy sector and possible risk factors incorporating Eurostat data on twenty-seven states, from 2011 to 2020. This study collected a different energy variable to support the multiple regression model constructed by the “blocks” (hierarchical linear regression) method. The results suggest that geopolitical risks cause adverse effects on both the energy and other corporate sectors. The future direction of this research is to estimate how statistical model relationships may assist the corporate sector, and investors, in adopting mitigating measures to control upcoming geopolitical risks due to energy risks caused by geopolitical unrest.info:eu-repo/semantics/publishedVersio

Could the ‘Spinner Innovation’ and ‘Triple Helix’ Models Improve System Innovation?

Although several prior studies have outlined and examined models associated with knowledge and innovation in different fields, the literature lacks any solid insights combining the Triple Helix model and the Spinner Innovation model and ascertaining their relevance to innovation. This article correspondingly presents an unprecedented alternative based on two innovation models, analyzing and structuring a process to innovate in different economic sectors. In doing so, this paper seeks to explore how this integration between Spinner Innovation and Triple Helix models could have a significant influence to improve system innovation. We collected data from the Scopus database spanning the period between 2012 and 2021 to study the integration of the models. The analysis identifies how these models differ but are nevertheless of complementary importance for developing regional and national economies through combining the “helices”, the “fidgets” and the framework integrating both models and their components to system innovation.info:eu-repo/semantics/publishedVersio

Shrinkage and flexural behaviour of free and restrained hybrid steel fibre reinforced concrete

The effect of restrained shrinkage on the mechanical performance of concrete and steel fibre reinforced concrete (SFRC) requires more investigation, especially when using recycled tyre steel fibre (RTSF). This paper examines the free and restrained shrinkage strains and the mechanical performance of seven SFRC mixes. Results show that both free and restrained average shrinkage strains are very similar in all blends of fibres and they exhibited non-uniform shrinkage through the height of the section. All examined blends meet strength requirements by MC-2010 for fibres to replace part of the conventional reinforcement in RC structures