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The high latitude ionospheric evolution of the May 10‐11, 2024, geomagnetic storm is investigated in terms of Total Electron Content and contextualized with Incoherent Scatter Radar and ionosonde observations. Substantial plasma lifting is observed within the initial Storm Enhanced Density plume with ionospheric peak heights increasing by 150–300 km, reaching levels of up to 630 km. Scintillation is observed within the cusp during the initial expansion phase of the storm, spreading across the auroral oval thereafter. Patch transport into the polar cap produces broad regions of scintillation that are rapidly cleared from the region after a strong Interplanetary Magnetic Field reversal at 2230UT. Strong heating and composition changes result in the complete absence of the F2‐layer on the eleventh, suffocating high latitude convection from dense plasma necessary for Tongue of Ionization and patch formation, ultimately resulting in a suppression of polar cap scintillation on the eleventh. Plain Language Summary The intense geomagnetic storm of May 2024 caused a plethora of different responses within the Earth's ionosphere. In the early phases of the storm, the auroral oval quickly expands to upper midlatitudes and induces strong variations in Global Navigation Satellite System (GNSS) phase measurements. Concurrently, midlatitude plasma is repeatedly lifted by 100–300 km on timescales of about an hour resulting in enhanced plasma densities. This intensified and lifted plasma is then drawn into the polar cap inducing variations in GNSS amplitude and phase. As the storm evolves, heating drives mixing of the thermosphere and causes an extreme depletion in ionospheric plasma. After 24 hr, despite severe geomagnetic conditions persisting, the depleted plasma environment results in only relatively weak plasma transport into the polar cap and significantly reduced impacts on GNSS. Key Points Plasma lifting during the storm caused midlatitude displacements of ionospheric peak height by as much as 300 km over the course of 1 hour Sporadic‐E is observed at the sub‐auroral convective boundary edge of the storm‐enhanced density with strong plasma drift shears present Severe depletion of electron density at mid and high latitudes significantly reduced the impact of subsequent geomagnetic activity on GNSS

In some of the most complex animal societies, individuals exhibit a cooperative division of labour to form castes. The most pronounced types of caste formation involve reproductive and non-reproductive forms that are morphologically distinct. In colonies comprising separate or mobile individuals, this type of caste formation has been recognized only among the arthropods, sea anemones and mole-rats. Here, we document physical and behavioural caste formation in a flatworm. Trematode flatworm parasites undergo repeated clonal reproduction of ‘parthenitae’ within their molluscan hosts forming colonies. We present experimental and observational data demonstrating specialization among trematode parthenitae to form distinct soldier and reproductive castes. Soldiers do not reproduce, have relatively large mouthparts, and are much smaller and thinner than reproductives. Soldiers are also more active, and are disproportionally common in areas of the host where invasions occur. Further, only soldiers readily and consistently attack heterospecifics and conspecifics from other colonies. The division of labour described here for trematodes is strongly analogous to that characterizing other social systems with a soldier caste. The parallel caste formation in these systems, despite varying reproductive mode and taxonomic affiliation, indicates the general importance of ecological factors in influencing the evolution of social behaviour. Further, the ‘recognition of self’ and the defence of the infected host body from invading parasites are comparable to aspects of immune defence. A division of labour is probably widespread among trematodes and trematode species encompass considerable taxonomic, life history and environmental diversity. Trematodes should therefore provide new, fruitful systems to investigate the ecology and evolution of sociality.

Swarm is the first European Space Agency (ESA) constellation mission for Earth Observation. Three identical Swarm satellites were launched into near-polar orbits on 22 November 2013. Each satellite hosts a range of instruments, including a Langmuir probe, GPS receivers, and magnetometers, from which the ionospheric plasma can be sampled and current systems inferred. In March 2018, the CASSIOPE/e-POP mission was formally integrated into the Swarm mission through ESA’s Earthnet Third Party Mission Programme. Collectively the instruments on the Swarm satellites enable detailed studies of ionospheric plasma, together with the variability of this plasma in space and in time. This allows the driving processes to be determined and understood. The purpose of this paper is to review ionospheric results from the first seven years of the Swarm mission and to discuss scientific challenges for future work in this field.

The modular multilevel converter with embedded batteries is a viable alternative in electric vehicle drive systems. This research investigates integrated charging of the embedded batteries in a three-phase converter from a single-phase source without any additional hardware requirements. Two phases of the converter are connected to the supply while the third converter leg is not connected. In a typical charging of the converter batteries, the batteries with a lower state of charge are prioritised. Then all batteries are balanced at an average global state of charge. This research proposes a new sorting algorithm of the converter batteries with an override capability to bypass any individual submodule if required. This bypassing capability is modulation method independent, thus can be integrated with any modulation method. Simulation results and a real-time emulation of the charging system validate the proposed control method and the override algorithm. In addition, an open-loop switching technique is integrated with a new nearest level control-based measurement method of the battery terminal voltage to estimate its initial state of charge. This measurement facilitates a reduced number of voltage sensors for hardware implementation. This method was simulated and validated by comparing the calculated and the measured values of the battery initial state of charge. Real-time emulation of the system utilising hardware-in-the-loop apparatus was carried out, which confirmed the developed control system functions as expected.

The present paper represents the second contribution in the Genera of Fungi series, linking type species of fungal genera to their morphology and DNA sequence data, and where possible, ecology. This paper focuses on 12 genera of microfungi, 11 of which the type species are neo- or epitypified here: Allantophomopsis (A. cytisporea, Phacidiaceae, Phacidiales, Leotiomycetes), Latorua gen. nov. (Latorua caligans, Latoruaceae, Pleosporales, Dothideomycetes), Macrodiplodiopsis (M. desmazieri, Macrodiplodiopsidaceae, Pleosporales, Dothideomycetes), Macrohilum (M. eucalypti, Macrohilaceae, Diaporthales, Sordariomycetes), Milospium (M. graphideorum, incertae sedis, Pezizomycotina), Protostegia (P. eucleae, Mycosphaerellaceae, Capnodiales, Dothideomycetes), Pyricularia (P. grisea, Pyriculariaceae, Magnaporthales, Sordariomycetes), Robillarda (R. sessilis, Robillardaceae, Xylariales, Sordariomycetes), Rutola (R. graminis, incertae sedis, Pleosporales, Dothideomycetes), Septoriella ( S. phragmitis, Phaeosphaeriaceae, Pleosporales, Dothideomycetes), Torula (T. herbarum, Torulaceae, Pleosporales, Dothideomycetes) and Wojnowicia (syn. of Septoriella, S. hirta, Phaeosphaeriaceae, Pleosporales, Dothideomycetes). Novel species include Latorua grootfonteinensis, Robillarda africana, R. roystoneae, R. terrae, Torula ficus, T. hollandica , and T. masonii spp. nov, and three new families: Macrodiplodiopsisceae, Macrohilaceae , and Robillardaceae. Authors interested in contributing accounts of individual genera to larger multi-authored papers to be published in IMA Fungus, should contact the associate editors listed for the major groups of fungi on the List of Protected Generic Names for Fungi ( www.generaoffungi.org ).

How arsenic (As) is transported in phloem remains unknown. To help answer this question, we quantified the chemical species of As in phloem and xylem exudates of castor bean (Ricinus communis) exposed to arsenate [As(V)], arsenite [As(III)], monomethylarsonic acid [MMA(V)], or dimethylarsinic acid. In the As(V)- and As(III)-exposed plants, As(V) was the main species in xylem exudate (55%-83%) whereas As(III) predominated in phloem exudate (70%-94%). The ratio of As concentrations in phloem to xylem exudate varied from 0.7 to 3.9. Analyses of phloem exudate using high-resolution inductively coupled plasma-mass spectrometry and accurate mass electrospray mass spectrometry coupled to high-performance liquid chromatography identified high concentrations of reduced and oxidized glutathione and some oxidized phytochelatin, but no As(III)-thiol complexes. It is thought that As(III)-thiol complexes would not be stable in the alkaline conditions of phloem sap. Small concentrations of oxidized glutathione and oxidized phytochelatin were found in xylem exudate, where there was also no evidence of As(III)-thiol complexes. MMA(V) was partially reduced to MMA(III) in roots, but only MMA(V) was found in xylem and phloem exudate. Despite the smallest uptake among the four As species supplied to plants, dimethylarsinic acid was most efficiently transported in both xylem and phloem, and its phloem concentration was 3.2 times that in xylem. Our results show that free inorganic As, mainly As(III), was transported in the phloem of castor bean exposed to either As(V) or As(III), and that methylated As species were more mobile than inorganic As in the phloem.

Studies on the rust fungus Puccinia arechavaletae, were conducted to determine its potential for use as a classical biological control agent against the alien environmental weed Cardiospermum grandiflorum in South Africa. The production of basidiospores is a crucial stage in the life cycle of this microcyclic rust species, and was determined to optimally occur at 20 °C, under high relative humidity (above 90%), in the presence of free water. The first basidiospores were released from mature telia after being incubated for 4 h under optimum conditions, reaching a peak of production after 24 h. Germination of basidiospores optimally occurred at 20 °C, and they were extremely vulnerable to desiccation. Germinating basidiospores directly penetrated epidermal cells of South African C. grandiflorum within which a vesicle formed, followed by rapid radial colonization of the leaf tissue by fungal mycelium. The first symptoms observed were small chlorotic spots on the leaves from 14 days onwards, with telial pustules appearing between 14 and 21 days post inoculation. The rust P. arechavaletae was shown to be highly pathogenic towards South African C. grandiflorum, causing severe disease symptoms with a detrimental effect on plant health and vigor.

Two-celled puccinioid teliospores are widely distributed in the rust fungi and appear in several independent lineages of the Pucciniales. About 25 genera in 4 families have been described. Species with two-celled teliospores occurring on members of the Annonaceae are described in the genera Dasyspora , Sphaerophragmium , Diorchidium , Puccinia , and Sphenospora . The molecular and morphological investigations from this study show that Diorchidium polyalthiae , Puccinia popowiae and Sphenospora xylopiae do not belong to the genera in which they were originally assigned. Aecidium deightonii was very closely related to S. xylopiae . Two new genera are erected to accommodate these taxa: (1) Puccorchidium , with the two species P. polyalthiae and P. popowiae ; and (2) Sphenorchidium , with the two species S. xylopiae and S. deightonii. They form a well-supported clade in the Pucciniales together with the genus Dasyspora , which also occurs on Annonaceae species, and Puccinia psidii the cause of myrtle rust. The type species of the genus Diorchidium , D. woodii , as well as Sphenospora pallida and S. smilacina appeared within the genus Puccinia . The endocyclic species Endophylloides guineensis occurs on the same host and in the same area as S. xylopiae and S. deightonii , but its relationship could not be determined without DNA data. A key for the rust fungi on Annonaceae with two-celled teliospores is given.

Polar holes were observed in the high-latitude ionosphere during a series of multi-instrument case studies close to the Northern Hemisphere winter solstice in 2014 and 2015. These holes were observed during geomagnetically quiet conditions and under a range of solar activities using the European Incoherent Scatter (EISCAT) Svalbard Radar (ESR) and measurements from Global Navigation Satellite System (GNSS) receivers. Steep electron density gradients have been associated with phase scintillation in previous studies; however, no enhanced scintillation was detected within the electron density gradients at these boundaries. It is suggested that the lack of phase scintillation may be due to low plasma density levels and a lack of intense particle precipitation. It is concluded that both significant electron density gradients and plasma density levels above a certain threshold are required for scintillation to occur.

Fig rust, caused by Cerotelium fici, was first recorded in South Africa in 1927. Recent observations have revealed high incidence of rust and untimely defoliation of fig trees (Ficus carica) in residential gardens and commercial orchards. Using phylogenetic analysis, the causal organism of a fig rust isolate (PREM63073) collected in 2020 was confirmed as Phakopsora nishidana. Inoculation and microscope studies showed that mulberry plants were immune to P. nishidana isolate PREM63073. Infection of fig leaves occurred through stomata on the abaxial leaf surfaces. Very long germ tubes were observed for P. nishidana, often with no clear contact with the leaf surfaces and an apparent lack of directional growth towards stomata. Inoculated plants from 15 fig cultivars varied in their severity of leaf infection, whereas fruit of the cultivar Kadota developed reddish-brown blemishes without sporulation. Currently, C. fici and P. nishidana are recognised as occurring on F. carica in South Africa. This suggests a need to resolve the worldwide distribution and identity of the rust species involved.