Bord na Móna (Ireland)

High-temperature superconducting (HTS) cable technology is appearing as a promising candidate for implementing bulk power Medium Voltage Direct Current (MVDC) corridors with reduced footprint and considerably lower losses. HTS demonstrators have achieved currents of 5-10 kA, raising a challenge for substation ratings, limited to 3 kA for Modular Multilevel Converter (MMC) and 6 kA for Line Commutated Converter (LCC) topologies. This paper studies topologies for implementing 10 kA/100 kV substations suited for HTS-based GW-scale MVDC links. The study addresses challenges and possible benefits of four high-current MMC-based substation designs in terms of hardware/control requirements, fault handling considerations and substation overall design (Valve Hall size modifications, AC/DC yards requirements). The first configuration presents challenges related to the increased energy per submodule, raising concerns regarding internal converter fault scenarios. The rest of the topologies use a standard submodule voltage and current rating matching those used in existing HVDC MMC designs. A 3D modelling approach is used to estimate valve hall size for each case and a reference 500 kV MMC hall of the same rating, with results showing potential for a 60% volume reduction. This size reduction is especially relevant in offshore applications, where size of platforms is a large cost driver.

Power systems are shifting towards a sustainable and interconnected future, where renewable power is transmitted over long distances to demand centers. This paper proposes a High Voltage Direct Current (HVDC) grid over a 6-zone AC/DC grid inspired by the European power system. The test case is analyzed with Optimal Power Flow (OPF) and Electromagnetic Transient (EMT) models in normal operations and for two contingency scenarios, namely loss of an HVDC link in the meshed AC/DC grid and loss of a radial HVDC link both in a congested hour. The results show how the HVDC grid helps avoid load curtailment when a link is lost in its meshed part. Furthermore, a robust control philosophy to maintain the power balance in hybrid AC/DC grids is discussed.

Wetlands are one of the major contributors of methane (CH4) emissions to the atmosphere and the intensity of emissions is driven by local environmental variables and spatial heterogeneity. Peatlands are a major wetland class and there are numerous studies that provide estimates of methane emissions at chamber or eddy covariance scales, but these are not often aggregated to the site/ecosystem scale. This study provides a robust approach to map dominant vegetation communities and to use these areas to upscale methane fluxes from chamber to site scale using a simple weighted-area approach. The proposed methodology was tested at three peatlands in Ireland over a duration of 2 years. The annual vegetation maps showed an accuracy ranging from 83 to 99% for near-natural to degraded sites respectively. The upscaled fluxes were highest (2.25 and 3.80 gC m−2 y−1) at the near-natural site and the rehabilitation (0.17 and 0.31 gC m−2 y−1), degraded (0.15 and 0.27 gC m−2 y−1) site emissions were close to net-zero throughout the study duration. Overall, the easy to implement methodology proposed in this study can be applied across various landuse types to assess the impact of peatland rehabilitation on methane emissions by mapping ecological change.

Background and Aim:Several reports described the detection of specific caprine arthritis-encephalitis virus (CAEV) antibodies in Russian goat populations, which indicates the circulation of CAEV in Russian goat farms. The aim of this study was to use a multi-target approach to testing with both serological tests and an in-house real-time (RT) molecular test to investigate the prevalence of CAEV in goats from three hobbyist farms in the Republic of Tatarstan, Russia.Materials and Methods:We applied a multi-target approach to testing with both enzyme-linked immunosorbent assay (ELISA) and an in-house RT polymerase chain reaction test to investigate the prevalence of CAEV in goats. Animals from the three hobbyist farms were used in this study. The animals from two farms (n=13 for F1 and n=8 for F2) had clinical signs of arthritis and mastitis. In the third farm (n=15 for F3), all goats were home-bred and had no contact with imported animals.Results:CAEV antibodies (ELISA targets TM env and gag genes) were detected in serum samples from two farms (F1 and F2), indicating seroprevalence of 87.50-92.31%. Specific CAEV antibodies were also detected in milk samples. CAEV proviral DNA was detected in 53.85-62.50%. The results from all tests performed in the third farm (F3) were negative, indicating that all tests were 100% specific.Conclusion:The results showed that CAEV is circulating and present in small hobbyist goat farms in Russia. Serological and molecular tests could be important for programs to control and eradicate CAEV in Russia for hobbyist goat farms.

Abstract Peatlands are the most efficient terrestrial carbon store on Earth, and deliver multiple other ecosystem services including climate regulation, water purification, preservation of ecological and archaeological records, etc. Disturbed and degraded peatlands do not provide the same ecological services and thus bear a significant cost to society. Because this cost may be alleviated by appropriate restoration measures, money is being invested in peatland restoration projects around the world. Here, we review over 25 years of restoration in Western Europe. First, we provide an overview of techniques used in different contexts and evaluate the status of the evidence base for restoration outcomes. Between 1993 and 2015, the EU‐LIFE nature programme alone invested 167.6M € in 80 projects, which aim to restore over 913 km2 of peatland habitats in Western European countries, mostly in protected sites part of the Natura 2000 EU network. This represents less than 2% of the total remaining area of peatlands in these countries, most of which have been impacted to some degree by anthropogenic disturbances. Potential for restoration should be considered in nondesignated sites. We reviewed a number of case studies covering a range of restoration approaches used in different parts of Western Europe. We found that published evidence of restoration progress was limited to specific sites/areas, and in many cases lacked baseline measurements and clear goals, that is, measurable target or contemporary reference(s). We discuss barriers and opportunities to turn the tide for peatland restoration in Western Europe and promote the establishment of robust, standardized monitoring schemes.

Within the huge number of microorganisms that exist, few are capable of causing disease in human beings, other animals and plants. External barriers to invasion include the skin and outer surfaces of animals, and the cuticle and bark in plants. Furthermore, in humans and many other higher vertebrates, internal mechanisms of defence such as antibodies may be produced as a response to microorganisms that breach structural defences. In plants, internal deterrents of microbial growth exist in the form of substances present in cell wall and intercellular spaces, and antimicrobial compounds may be released from vacuoles following cell damage. External stimuli may trigger the production and release of antimicrobial compounds from plants.

Efforts to develop a better diagnostic assay for bovine tuberculosis have shown that the sensitivity and specificity of an assay can be improved by the use of two or more antigens. As reported here, we developed a multiplex chemiluminescent immunoassay that can simultaneously detect antibody activity to 25 antigens in a single well in a 96-well plate array format. The chemiluminescent signal is captured with a digital imaging system and analyzed with a macro program that tracks each serum for its pattern of antibody activity for Mycobacterium bovis antigens. The comparison of sera from 522 infected and 1,489 uninfected animals showed that a sensitivity of 93.1% and a specificity of 98.4% can be achieved with a combination of antigens. The assay system is rapid and can be automated for use in a centralized laboratory.