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Abstract Taking into account trophic relationships in seagrass meadows is crucial to explain and predict seagrass temporal trajectories, as well as for implementing and evaluating seagrass conservation policies. However, this type of interaction has been rarely investigated over the long term and at the scale of the whole seagrass habitat. In this work, reciprocal links between an intertidal seagrass species, Zostera noltei, and a herbivorous bird feeding on this seagrass species, the migratory goose Branta bernicla bernicla, were investigated using an original combination of long‐term Earth Observation (EO) and bird census data. Seagrass Essential Biodiversity Variables (EBVs) such as seagrass abundance and phenology were measured from 1985 to 2020 using high‐resolution satellite remote sensing over Bourgneuf Bay (France), and cross‐analysed with in situ measurements of bird population size during the goose wintering season. Our results showed a mutual relationship between seagrass and Brent geese over the four last decades, suggesting that the relationship between the two species extends beyond a simple grass—herbivore consumptive effect. We provided evidence of two types of interactions: (i) a bottom‐up control where the late‐summer seagrass abundance drives the wintering population of herbivorous geese and (ii) an indirect top‐down effect of Brent goose on seagrass habitat, where seagrass development is positively influenced by the bird population during the previous wintering season. Such a mutualistic relationship has strong implications for biodiversity conservation because protecting one species is beneficial to the other one, as demonstrated here by the positive trajectories observed from 1985 to 2020 in both seagrass and bird populations. Importantly, we also demonstrated here that exploring the synergy between EO and in situ bird data can benefit seagrass ecology and ecosystem management.

Abstract Place names are an important but vanishing part of cultural diversity, and their relevance for environmental sciences is increasingly acknowledged. Still little is known about whether the diversity of toponyms affects human–nature relationships and the decisions of humans on how to use certain parts of the landscape. To investigate this question, we combined approaches from social sciences and ecology in a comprehensive multidisciplinary survey of 1521 cultural landscape features in Hungary. The landscape features studied were ancient millennia‐old burial earthen mounds built by nomadic steppic tribes, that often hold the last remnants of grassland vegetation and provide safe havens for grassland specialist plant and animal species in the intensively used agricultural landscapes of Eurasia. In our research, we (i) compiled a comprehensive database of the mounds in the 5150 km2‐sized study region, (ii) collected all toponyms of the mounds recorded since the 18th century, (iii) derived the height and distance from settlements for each mound and (iv) visited all the mounds in a field survey, and evaluated their vegetation naturalness. We found that despite the intensive landscape transformation in the region, and independently of topographical factors, a higher number of toponyms was associated with a higher degree of naturalness of the vegetation on the landscape features. Independently of the protective effect of the height of the mound against ploughing, and the distance from settlements that reflects to decreasing land use intensity, we found that the vegetation on the mounds with more names had a higher degree of naturalness. Synthesis and applications. Cultural recognition of these places has eroded considerably in the past centuries, but its effect is still noticeable, suggesting an extinction delay of culture‐driven biodiversity patterns. Our results suggest that reestablishment of the lost cultural connections between people and nature can contribute to reversing the deterioration. Read the free Plain Language Summary for this article on the Journal blog.

Abstract Background Language deficits are cardinal manifestations of some frontotemporal dementia (FTD) phenotypes and also increasingly recognized in sporadic and familial amyotrophic lateral sclerosis (ALS). They have considerable social and quality‐of‐life implications, and adaptive strategies are challenging to implement. While the neuropsychological profiles of ALS–FTD phenotypes are well characterized, the neuronal underpinnings of language deficits are less well studied. Methods A multiparametric, quantitative neuroimaging study was conducted to characterize the involvement of language‐associated networks, tracts, and cortical regions with a panel of structural, diffusivity, and functional magnetic resonance imaging (MRI) metrics. Seven study groups were evaluated along the ALS–FTD spectrum: healthy controls (HC), individuals with ALS without cognitive impairment (ALSnci), C9orf72‐negative ALS–FTD, C9orf72‐positive ALS–FTD, behavioral‐variant FTD (bvFTD), nonfluent variant primary progressive aphasia (nfvPPA), and semantic variant PPA (svPPA). The integrity of the Broca's area, Wernicke's area, frontal aslant tract (FAT), arcuate fascicle (AF), inferior occipitofrontal fascicle (IFO), inferior longitudinal fascicle (ILF), superior longitudinal fascicle (SLF), and uncinate fascicle (UF) was quantitatively evaluated. The functional connectivity (FC) between Broca's and Wernicke’ areas and FC along the FAT was also specifically assessed. Results Patients with nfvPPA and svPPA exhibit distinctive patterns of gray and white matter degeneration in language‐associated brain regions. Individuals with bvFTD exhibit Broca's area, right FAT, right IFO, and UF degeneration. The ALSnci group exhibits Broca's area atrophy and decreased FC along the FAT. Both ALS–FTD cohorts, irrespective of C9orf72 status, show bilateral FAT, AF, and IFO pathology. Interestingly, only C9orf72‐negative ALS–FTD patients exhibit bilateral uncinate and right ILF involvement, while C9orf72‐positive ALS–FTD patients do not. Conclusions Language‐associated tracts and networks are not only affected in language‐variant FTD phenotypes but also in ALS and bvFTD. Language domains should be routinely assessed in ALS irrespective of the genotype.

Abstract Agri‐environment schemes (AES) incentivise land‐management practices aimed at mitigating environmental impacts. However, their effectiveness depends on the duration and type of management. We modelled the potential for grassland AES options in Wales (UK) to achieve positive changes in plant diversity via change in soil conditions. We modelled the response of plants and soils to the predicted effects of AES options over a 13‐year time interval. We applied scenarios of change in soil conditions in three managed grassland types, using high‐resolution baseline soil and vegetation data collected in grasslands across Wales, UK. We also applied scenarios of climate change to determine the extent to which this might modify the impact of AES intervention on plant species compositional turnover. Empirical models of soil response to extensification were constructed from published experimental data and used to drive change in soil inputs to a small ensemble of ecological niche models for British plants. These models were applied to the local pool of species in each baseline (2 × 2 m) quadrat plus a wider 10 × 10 km pool from which we draw species absent at baseline but predicted to find conditions suitable as a result of AES intervention and climate change, thus estimating dark diversity at each location. Outputs were summarised by grouping species by the ecosystem functions and services they support and by matching projected species composition to the UK National Vegetation Classification. Scenario modelling indicated that at least 10 years of management under grassland AES options were needed to achieve conditions suitable for desirable plant assemblages more typical of lower fertility habitats. Synthesis and applications: We predict that management effects will have a more marked effect on vegetation and soil than predicted climate variation up to 2029. Realising modelled changes in habitat suitability as species compositional turnover and community assembly is likely to require additional measures to assist plant dispersal and establishment.

Introduction The emergence of mechanical thrombectomy (MT) as a standard of care has revolutionized the management of proximal large vessel occlusions (LVOs) in patients with acute ischemic stroke (AIS). Endovascular therapy has already been shown to provide better long‐term outcomes when compared to standard treatment alone. However, despite the significant advances and benefits associated with MT in the treatment of proximal LVOs in developed countries, Africa continues to lag in the use and adaptability of the “gold standard” for proximal LVO stroke treatment. With the prevalence of stroke in Africa approaching the highest rates in the world, this study seeks to highlight the problems threatening endovascular therapy in Africa. This is an important step in advocacy for more radical, effective, and evidence‐based management of patients with proximal LVOs in Africa. Methods For this narrative review, PubMed and Google Scholar were used to search for literature on mechanical thrombectomy and endovascular treatment of LVOs in Africa. Selection criteria were manuscripts published in the last 10 years, written in English language, and addressed challenges with MT. Results 42 papers from 21 African nations were found and reviewed. The major challenges and impediments to MT in Africa were, a lack of government policy on stroke care, a suboptimal health care financing model that makes endovascular treatment nearly impossible to afford, delay in presenting to the hospital after stroke onset coupled with very few emergency services with some countries having none, lack of specialized training, as well as, scarcity of neuroradiological infrastructure. Conclusions Despite these challenges, there is still hope for Africa. With its four domains (surveillance, prevention, acute treatment, and rehabilitation), the stroke quadrangle, adapted by many countries allows for focused initiatives aimed at successfully lowering the burden of stroke in Africa at the community level through prevention and education. There is still an urgent need for increased global support to address these challenges in Africa, even as programs like the MT2020+ by the Society of Vascular and Interventional Neurology (SVIN) have given Africa hope for the future of endovascular therapy by fostering collaboration, training, and policy development.

Abstract Background The cause of the motor neuron (MN) death that drives terminal pathology in amyotrophic lateral sclerosis (ALS) remains unknown, and it is thought that the cellular environment of the MN may play a key role in MN survival. Several lines of evidence implicate vesicles in ALS, including that extracellular vesicles may carry toxic elements from astrocytes towards MNs, and that pathological proteins have been identified in circulating extracellular vesicles of sporadic ALS patients. Because MN degeneration at the neuromuscular junction is a feature of ALS, and muscle is a vesicle‐secretory tissue, we hypothesized that muscle vesicles may be involved in ALS pathology. Methods Sporadic ALS patients were confirmed to be ALS according to El Escorial criteria and were genotyped to test for classic gene mutations associated with ALS, and physical function was assessed using the ALSFRS‐R score. Muscle biopsies of either mildly affected deltoids of ALS patients (n = 27) or deltoids of aged‐matched healthy subjects (n = 30) were used for extraction of muscle stem cells, to perform immunohistology, or for electron microscopy. Muscle stem cells were characterized by immunostaining, RT‐qPCR, and transcriptomic analysis. Secreted muscle vesicles were characterized by proteomic analysis, Western blot, NanoSight, and electron microscopy. The effects of muscle vesicles isolated from the culture medium of ALS and healthy myotubes were tested on healthy human‐derived iPSC MNs and on healthy human myotubes, with untreated cells used as controls. Results An accumulation of multivesicular bodies was observed in muscle biopsies of sporadic ALS patients by immunostaining and electron microscopy. Study of muscle biopsies and biopsy‐derived denervation‐naïve differentiated muscle stem cells (myotubes) revealed a consistent disease signature in ALS myotubes, including intracellular accumulation of exosome‐like vesicles and disruption of RNA‐processing. Compared with vesicles from healthy control myotubes, when administered to healthy MNs the vesicles of ALS myotubes induced shortened, less branched neurites, cell death, and disrupted localization of RNA and RNA‐processing proteins. The RNA‐processing protein FUS and a majority of its binding partners were present in ALS muscle vesicles, and toxicity was dependent on the expression level of FUS in recipient cells. Toxicity to recipient MNs was abolished by anti‐CD63 immuno‐blocking of vesicle uptake. Conclusions ALS muscle vesicles are shown to be toxic to MNs, which establishes the skeletal muscle as a potential source of vesicle‐mediated toxicity in ALS.

Abstract Background Frontotemporal dementia (FTD) phenotypes are classically associated with distinctive cortical atrophy patterns and regional hypometabolism. However, the spectrum of cognitive and behavioral manifestations in FTD arises from multisynaptic network dysfunction. The thalamus is a key hub of several corticobasal and corticocortical circuits. The main circuits relayed via the thalamic nuclei include the dorsolateral prefrontal circuit, the anterior cingulate circuit, and the orbitofrontal circuit. Methods In this paper, we have reviewed evidence for thalamic pathology in FTD based on radiological and postmortem studies. Original research papers were systematically reviewed for preferential involvement of specific thalamic regions, for phenotype‐associated thalamic disease burden patterns, characteristic longitudinal changes, and genotype‐associated thalamic signatures. Moreover, evidence for presymptomatic thalamic pathology was also reviewed. Identified papers were systematically scrutinized for imaging methods, cohort sizes, clinical profiles, clinicoradiological associations, and main anatomical findings. The findings of individual research papers were amalgamated for consensus observations and their study designs further evaluated for stereotyped shortcomings. Based on the limitations of existing studies and conflicting reports in low‐incidence FTD variants, we sought to outline future research directions and pressing research priorities. Results FTD is associated with focal thalamic degeneration. Phenotype‐specific thalamic traits mirror established cortical vulnerability patterns. Thalamic nuclei mediating behavioral and language functions are preferentially involved. Given the compelling evidence for considerable thalamic disease burden early in the course of most FTD subtypes, we also reflect on the practical relevance, diagnostic role, prognostic significance, and monitoring potential of thalamic metrics in FTD. Conclusions Cardinal manifestations of FTD phenotypes are likely to stem from thalamocortical circuitry dysfunction and are not exclusively driven by focal cortical changes.