Defining the Optimal Strategies for Achieving Drug-Free Remission in Rheumatoid Arthritis: A Narrative Review

Background: It is now accepted that the optimum treatment goal for rheumatoid arthritis (RA) is sustained remission, as this has been shown to be associated with the best patient outcomes. There is little guidance on how to manage patients once remission is achieved; however, it is recommended that patients can taper therapy, with a view to discontinuing and achieving drug-free remission if treatment goals are maintained. This narrative review aims to present the current literature on drug-free remission in rheumatoid arthritis, with a view to identifying which strategies are best for disease-modifying anti-rheumatic drug (DMARD) tapering and to highlight areas of unmet clinical need. Methods: We performed a narrative review of the literature, which included research articles, meta-analyses and review papers. The key search terms included were rheumatoid arthritis, remission, drug-free remission, b-DMARDS/biologics, cs-DMARDS and tapering. The databases that were searched included PubMed and Google Scholar. For each article, the reference section of the paper was reviewed to find additional relevant articles. Results: It has been demonstrated that DFR is possible in a proportion of RA patients achieving clinically defined remission (both on cs and b-DMARDS). Immunological, imaging and clinical associations with/predictors of DFR have all been identified, including the presence of autoantibodies, absence of Power Doppler (PD) signal on ultrasound (US), lower disease activity according to composite scores of disease activity and lower patient-reported outcome scores (PROs) at treatment cessation. Conclusions: DFR in RA may be an achievable goal in certain patients. This carries importance in reducing medication-induced side-effects and potential toxicity, the burden of taking treatment if not required and cost effectiveness, specifically for biologic therapy. Prospective studies of objective biomarkers will help facilitate the prediction of successful treatment discontinuation.

The Eurocentrism of neo-Roman republicanism and the neglect of republican empire

Republicanism is an approach within political theory that seeks to secure the values of political liberty and non-domination. Yet, in historical practice, early modern republics developed empires and secured their liberty through policies that dominated others. This contradiction presents challenges for how neo-Roman theorists understand ideals of liberty and political freedom. This article argues that the historical practices of slavery and empire developed concurrently with the normative ideals of republican liberty. Republican liberty does not arise in the absence of power but is inherently connected to the exercise of power.

Gate Drives generating EMI in the absence of Power Converter loading

This paper shows how a power converter can generate electromagnetic interference (EMI) through the operation of gate drives only - in the absence of any power conversion. This is due to parasitic capacitances connecting the power semiconductor’s gate to the main circuit. A half bridge converter is used to illustrate this concept. Practical measurements are compared to simulations for an energized and non-energized converter. Even without loading, a converter can exceed regulatory conducted emission EMI limits. This effect is important to consider during the design of converter EMI mitigation - especially for low power converters where the load current is not dominant.

Gate Drives generating EMI in the absence of Power Converter loading

This paper shows how a power converter can generate electromagnetic interference (EMI) through the operation of gate drives only - in the absence of any power conversion. This is due to parasitic capacitances connecting the power semiconductor’s gate to the main circuit. A half bridge converter is used to illustrate this concept. Practical measurements are compared to simulations for an energized and non-energized converter. Even without loading, a converter can exceed regulatory conducted emission EMI limits. This effect is important to consider during the design of converter EMI mitigation - especially for low power converters where the load current is not dominant.

Beating Carnot efficiency with periodically driven chiral conductors

Classically, the power generated by an ideal thermal machine cannot be larger than the Carnot limit. This profound result is rooted in the second law of thermodynamics. A hot question is whether this bound is still valid for microengines operating far from equilibrium. Here, we demonstrate that a quantum chiral conductor driven by AC voltage can indeed work with efficiencies much larger than the Carnot bound. The system also extracts work from common temperature baths, violating Kelvin-Planck statement. Nonetheless, with the proper definition, entropy production is always positive and the second law is preserved. The crucial ingredients to obtain efficiencies beyond the Carnot limit are: i) irreversible entropy production by the photoassisted excitation processes due to the AC field and ii) absence of power injection thanks to chirality. Our results are relevant in view of recent developments that use small conductors to test the fundamental limits of thermodynamic engines.

Development of the design of an internal combustion engine cooling system with a pre-starting heating function

The main topic of the article is the development of an effective design for a pre-starting heating system for an internal combustion engine for conditions of limited power supply. The work to im-prove the design of light wheeled all-terrain vehicles on low pressure pneumatics is done at Pacific National University. Prototypes of light wheeled off-road vehicles are used mainly in agriculture and for forestry production. There are prerequisites for their use in oil and gas fields in the Far North conditions. This vehicle is operated all year round, in the absence of power supply, it is stored in the open air, so the problem of starting a cold engine is quite important, and the topic of creating a design for a pre-starting heating system for an internal combustion engine under conditions of limited or com-plete absence of power supply is relevant. The purpose of the work is to develop and study the efficiency of the pre-starting heating system for an internal combustion engine with liquid cooling for conditions of limited power supply. Our own design of the cooling system with a pre-starting heating function based on a gasoline burner was developed. To assess the efficiency of the engine warm-up process, the circuit was as-sembled on a light wheeled all-terrain vehicle. The experimental studies were carried out to deter-mine the regularity of changes in the temperature of the engine coolant during pre-starting heating at different ambient temperatures. The results of the experiment indicate the high efficiency of the developed system based on a gasoline burner. The average heating rate of the engine coolant during the warm-up process was 2.1 - 2.8 оС per minute, which indicates an intensive pace of pre-starting heating.

Methodology for assessing the efficiency of water jet pumps in auxiliary systems of irrigation pumping stations

The reliability and efficiency of irrigation pumping stations operation primarily depends on the well-coordinated operation of all systems. Drainage system should ensure that the building and territory of the pumping station are not flooded by drainage (filtration) water. At many pumping stations (especially those with long pressure lines), water jet pumps are installed as pumps for pumping out drainage water. The experience of operating such plants has revealed their undeniable advantages in comparison with conventional vane centrifugal pumps (type K and D) – sufficient reliability in operation due to the simplicity of the design, the absence of rubbing parts in the installation, the possibility of pumping contaminated liquids and the possibility of their use in the absence of power supply. But with all this, water jet pumps are extremely low-efficiency. To justify the use of jet pumps, a methodology is needed that would allow for a comprehensive consideration of all the main factors that affect their reliability, ease of operation and energy efficiency in the drainage system. On the example of the pumping station “Kiziltepa-2”, these factors were identified and the energy efficiency of water jet pumps was calculated. Various applications of jet pumps are considered, and their efficiency is evaluated.

Optimal Operation of Networked Microgrids for Enhancing Resilience Using Mobile Electric Vehicles

The increased intensity and frequency of natural disasters have attracted the attention of researchers in the power sector to enhance the resilience of power systems. Microgrids are considered as a potential solution to enhance the resilience of power systems using local resources, such as renewable energy sources, electric vehicles (EV), and energy storage systems. However, the deployment of an additional storage system for resilience can increase the investment cost. Therefore, in this study, the usage of existing EVs in microgrids is proposed as a solution to increase the resilience of microgrids with outages without the need for additional investment. In the case of contingencies, the proposed algorithm supplies energy to islanded microgrids from grid-connected microgrids by using mobile EVs. The process for the selection of EVs for supplying energy to islanded microgrids is carried out in three steps. Firstly, islanded and networked microgrids inform the central energy management system (CEMS) about the required and available energy stored in EVs, respectively. Secondly, CEMS determines the microgrids among networked microgrids to supply energy to the islanded microgrid. Finally, the selected microgrids determine the EVs for supplying energy to the islanded microgrid. Simulations have shown the effectiveness of the proposed algorithm in enhancing the resilience of microgrids even in the absence of power connection among microgrids.

Experimental Evidence of the Viability of Thermoelectric Generators to Power Volcanic Monitoring Stations

Although there is an important lack of commercial thermoelectric applications mainly due to their low efficiency, there exist some cases in which thermoelectric generators are the best option thanks to their well-known advantages, such as reliability, lack of maintenance and scalability. In this sense, the present paper develops a novel thermoelectric application in order to supply power to volcanic monitoring stations, making them completely autonomous. These stations become indispensable in any volcano since they are able to predict eruptions. Nevertheless, they present energy supply difficulties due to the absence of power grid, the remote access, and the climatology. As a solution, this work has designed a new integral system composed of thermoelectric generators with high efficiency heat exchangers, and its associated electronics, developed thanks to Internet of Things (IoT) technologies. Thus, the heat emitted from volcanic fumaroles is transformed directly into electricity with thermoelectric generators with passive heat exchangers based on phase change, leading to a continuous generation without moving parts that powers different sensors, the information of which is emitted via LoRa. The viability of the solution has been demonstrated both at the laboratory and at a real volcano, Teide (Canary Islands, Spain), where a compact prototype has been installed in an 82 °C fumarole. The results obtained during more than eight months of operation prove the robustness and durability of the developed generator, which has been in operation without maintenance and under several kinds of meteorological conditions, leading to an average generation of 0.49 W and a continuous emission over more than 14 km.