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Mathews, F.

Publications and source records attributed to Mathews, F..

8 recordsLinked to original sources

Stopover departure decisions and movement patterns of migratory bats during autumn migration

Migrating bats alternate between stopover periods and directed flights. When departing from a stopover site, bats select the night, the specific time within the night, and the flight direction to resume migration. Despite their ecological importance, the factors shaping these stopover departure decisions remain poorly understood. To identify the intrinsic and environmental factors driving departure decisions and movement patterns, we tagged Nathusius pipistrelles Pipistrellus nathusii at three coastal locations in the Netherlands and tracked 178 individuals during autumn migration, using the MOTUS Wildlife Tracking System. We examined movement patterns and analysed departure probability in relation to a set of individual and environmental covariates in a Bayesian capture-recapture model in state-space formulation. Additionally, we modelled within-night variation in departure timing. Seasonal patterns were strongly influenced by reproductive behaviour, with decreased migration probability during the mating period. Regardless of their seasonal timing, bats departed under moderate tailwinds and dry conditions, optimizing energy efficiency, while avoiding crosswinds and cloud cover, enhancing navigational safety. Most individuals departed shortly after sunset, whereas headwinds delayed nocturnal departure. Movement patterns were diverse, including migration towards lower latitudes, coastal barrier movements, and long-distance roundtrips, suggesting the use of multiple movement strategies. Our study demonstrates that migration patterns in bats emerge from the interaction between intrinsic factors and external conditions, and highlights the importance of both energy efficiency and safety in shaping stopover departure decisions. The presence of multiple movement strategies complicates predictions of spatiotemporal occurrence, emphasising the need to account for behavioural variability in conservation planning, for example in the context of wind energy developments.

ecology↗

Development of species-specific real-time PCR assays for the identification of five European Rhinolophus bats.

The detection and monitoring of bat species using non-invasive sampling and molecular techniques has become increasingly popular in recent years. In Europe, these approaches have been applied to identify horseshoe bats of the genus Rhinolophus, which includes five species: R. hipposideros, R. ferrumequinum, R. euryale, R. mehelyi and R. blasii. While species-specific real-time PCR assays exist for R. ferrumequinum and R. hipposideros, no unified panel of real-time PCR assays currently enables the identification of all five European Rhinolophus species from non-invasively collected samples. Here, we developed five species-specific real-time PCR assays, each targeting interspecies nucleotide variation within the mitochondrial cytochrome b gene. To enhance single-base discrimination, RNase H-dependent PCR (rhPCR) primers were employed, incorporating cleavable blocked primers that require perfect complementarity for extension. The assays were applied to droppings non-invasively collected from 18 caves and one church in Serbia and Romania. Of the 149 samples analysed, 131 (88%) yielded successful amplification of Rhinolophus DNA. Detection probabilities for the three species identified in the field ranged from 0.49 to 0.82. Occupancy estimates varied, with R. euryale showing the highest (0.86; UI: 0.69-0.97) and R. mehelyi the lowest (0.23; UI: 0.08-0.43). The assays were capable of detecting up to three species concurrently within a single pooled sample (approximately 15 droppings). These assays are especially valuable for detecting R. mehelyi, given its rarity and uncertain distribution, and offer a robust tool for monitoring Rhinolophus populations across Europe.

ecology↗

Directional variation and method-specific detection patterns in offshore bat migration: implications for wind farm mitigation

O_LICurtailment of wind farms effectively reduces collision mortality in bats. Implementing this measure in offshore wind farms requires knowledge on the spatiotemporal occurrence and environmental predictors of migration over sea. In bats, such information can be obtained through acoustic monitoring and individual tracking. However, these techniques provide seemingly contradictory insights into migration patterns. C_LIO_LIWe used a Bayesian capture-recapture state-space model to investigate how environmental predictors influence spring departure decisions of Nathusius pipistrelle Pipistrellus nathusii migrating over the North Sea. The model was applied to both acoustic and tracking data, enabling comparable analyses across methods and incorporating uncertainty in migration dates of tracked bats. Additionally, we examined nightly offshore bat occurrence to further explore differences in movement patterns detected by the two techniques. C_LIO_LIWind conditions at 200 m above sea level were identified as key driver of Nathusius pipistrelle spring migration. In May-June, most bats migrated from the United Kingdom under westerly and northwesterly tailwinds. Tracked individuals flew in stronger supportive winds than acoustically recorded bats, which were also detected under crosswinds and headwinds. In March-April, acoustic detections occurred mainly during strong southerly winds, suggesting that early-season migrants largely consisted of individuals migrating over the European mainland and drifted northwards onto the North Sea by strong crosswinds. C_LIO_LIAcoustic detectors primarily recorded bats that landed on offshore platforms, likely because they were unable to cross the North Sea in a single flight due to less favorable wind conditions, or because they departed from more inland locations. In contrast, tracking data mainly represented bats that successfully crossed the North Sea in a non-stop flight under moderate supportive tailwinds. C_LIO_LISynthesis and applications: Combining observation techniques improves our understanding of bat migration patterns. Additionally, acoustic monitoring can capture migration from different geographic origins. Current mitigation measures for offshore wind farms at the North Sea rely solely on acoustic data, likely overlooking the part of the population that crosses over sea with optimal wind support. Acoustic and tracking data are therefore complementary rather than contradictory, and both methods should be used together when developing mitigation measures. C_LI

ecology↗

Lack of detection of SARS-CoV-2 in British wildlife 2020-21 and first description of a stoat (Mustela erminea) Minacovirus

2.Repeat spillover of SARS-CoV-2 into new hosts has highlighted the critical role of cross species transmission of coronaviruses and establishment of new reservoirs of virus in pandemic and epizootic spread of coronaviruses. Species particularly susceptible to SARS-CoV-2 spill-over include Mustelidae (mink, ferrets and related animals), cricetid rodents (hamsters and related animals), felids domestic cats and related animals) and white tailed deer. These predispositions led us to screen British wildlife with sarbecovirus specific qPCR and pan coronavirus PCR assays for SARS-CoV-2 using samples collected during the human pandemic to establish if widespread spill-over was occurring. Fourteen wildlife species (n=402) were tested, including : 2 Red Foxes (Vulpes vulpes), 101 Badgers (Meles meles), 2 wild American Mink (Neogale vison), 41 Pine Marten (Martes martes), 2 Weasels (Mustela nivalis), 7 Stoats (Mustela erminea), 108 Water Voles (Arvicola amphibius), 39 Bank voles (Myodes glareolous), 10 Field Voles (Microtus agrestis), 15 Wood Mice (Apodemus sylvaticus), 1 Common Shrew (Sorex aranaeus), 2 Pygmy Shrews (Sorex minutus), 2 Hedgehogs (Erinaceus europaeus) and 75 Eurasian Otters (Lutra lutra). No cases of SARS-CoV-2 were detected in any animals, however a novel minacovirus related to mink and ferret alphacoronaviruses was detected in stoats recently introduced to the Orkney Islands. This group of viruses is of interest due to pathogenicity in ferrets. The impact of this virus on the health of stoat populations remains to be established.

microbiology↗

Cultured Mesenchymal Cells from Nasal Turbinate as a Cellular Model of the Neurodevelopmental Component of Schizophrenia Etiology

Study of the neurodevelopmental molecular mechanisms of schizophrenia requires the development of adequate biological models such as patient-derived cells and their derivatives. We previously used cell lines with neural progenitor properties (CNON) derived from superior or middle turbinates of patients with schizophrenia and control groups to study gene expression specific to schizophrenia. In this study, we compared single cell-RNA seq data from two CNON cell lines, one derived from an individual with schizophrenia (SCZ) and the other from a control group, with two biopsy samples from the middle turbinate (MT), also from an individual with SCZ and a control. In addition, we compared our data with previously published data from olfactory neuroepithelium (1). Our data demonstrated that CNON originated from a single cell type which is present both in middle turbinate and olfactory neuroepithelium. CNON express multiple markers of mesenchymal cells. In order to define relatedness of CNON to the developing human brain, we also compared CNON datasets with scRNA-seq data of embryonic brain (2) and found that the expression profile of CNON very closely matched one of the cell types in the embryonic brain. Finally, we evaluated differences between SCZ and control samples to assess usability and potential benefits of using single cell RNA-seq of CNON to study etiology of schizophrenia.

cell biology↗

Sarbecoviruses of British Horseshoe Bats; Sequence Variation and Epidemiology

Horseshoe bats are the natural hosts of the Sarbecovirus subgenus that includes SARS-CoV-1 and 2. Despite the devastating impacts of the COVID-19 pandemic, there is still little known about the underlying epidemiology and virology of sarbecoviruses in their natural hosts, leaving large gaps in our pandemic preparedness. Here we describe the results of PCR testing for sarbecoviruses in the two horseshoe bat species (Rhinolophus hipposideros and R. ferrumequinum) present in Great Britain, collected in 2021-22 during the peak of COVID-19 pandemic. One hundred and ninety seven R. hipposideros samples from 33 roost sites and 277 R. ferremequinum samples from 20 roost sites were tested. No coronaviruses were detected in any samples from R. ferrumequinum whereas 44% and 56% of individual and pooled (respectively) faecal samples from R. hipposideros across multiple roost sites tested positive in a sarbecovirus-specific qPCR. Full genome sequences were generated from three of the positive samples (and partial genomes from two more) using Illumina RNAseq on unenriched samples. Phylogenetic analyses showed that the obtained sequences belong to the same monophyletic clade, with >95% similarity, as previously reported European isolates from R. hipposideros. The sequences differed in the presence or absence of accessory genes ORF 7b, 9b and 10. All lacked the furin cleavage site of SARS-CoV-2 spike gene and are therefore unlikely to be infective for humans. These results demonstrate a lack, or at least low incidence, of SARS-CoV-2 spill over from humans to susceptible GB bats, and confirm that sarbecovirus infection is widespread in R. hipposideros. Despite frequently sharing roost sites with R. ferrumequinum, no evidence of cross-species transmission was found.

microbiology↗

Cell type catalog of middle turbinate epithelium

ImportanceElucidation of the cellular makeup of the middle turbinate provides a foundation for future studies of pathogenesis of sinonasal disease. Neural progenitors and pluripotent basal cells found in middle turbinate mucosa potentially can be used to develop cellular models to study brain disorders or in regenerative medicine to substitute neuronal tissues. ObjectiveSingle cell RNA-sequencing (scRNA-seq) of middle turbinate mucosa was performed to create the first single cell transcriptome catalog of this part of the human body. DesignSamples were obtained from the head of the middle turbinate from healthy volunteers. After the specimen was prepared per lab protocol, cells were dissociated, suspended, and counted. Single cell libraries were then prepared according to the 10x Genomics protocol and sequenced using NovaSeq 6000 (Illumina). Sequencing data were processed using Cell Ranger, and clustering and gene expression analysis was performed using Seurat. Cell types were annotated using known markers and data from other single cell studies. SettingSingle center, tertiary care center ParticipantsHealthy volunteer Intervention(s) (for clinical trials) or Exposure(s) (for observational studies)None Main Outcome(s) and Measure(s)Identification of cell types of middle turbinate mucosa through expression profiling of single cells using known markers Results14 unique cell types were identified, including serous, goblet, club, basal, ciliated, endothelial, and neural progenitor cells, as well as multiple types of blood cells. Conclusions and RelevanceThis catalog provides a comprehensive depiction of the cellular composition of middle turbinate mucosa. By uncovering the cellular stratification of gene expression profiles in healthy middle turbinate epithelium, the groundwork has been laid for further investigation into the molecular pathogenesis and targeted therapy of sinonasal disease. Key PointsO_ST_ABSQuestionC_ST_ABSWhat is the cellular makeup of human middle turbinate mucosa? FindingsSingle-cell RNA sequencing revealed 14 cell types in middle turbinate epithelium, including neural progenitors, a previously unrecognized component of middle turbinate epithelium. MeaningGene expression profiles of middle turbinate mucosa cell types are concordant with other respiratory mucosa transcriptomic data with notable heterogeneity in serous and basal cells.{square}

genomics↗

Integrating population genetics to define conservation units from the core to the edge of Rhinolophus ferrumequinum western range

The greater horseshoe bat (Rhinolophus ferrumequinum) is among the most widespread bat species in Europe but it has experienced severe declines, especially in Northern Europe. This species is listed Near Threatened in the European IUCN Red List of Threatened Animals and it is considered to be highly sensitive to human activities and particularly to habitat fragmentation. Therefore, understanding the population boundaries and demographic history of populations of this species is of primary importance to assess relevant conservation strategies. In this study, we used 17 microsatellite markers to assess the genetic diversity, the genetic structure and the demographic history of R. ferrumequinum colonies in the Western European part of its distribution. We found high levels of genetic diversity and large population size on the European mainland and lower estimates in England and Northern France. Analyses of clustering and isolation by distance showed a barrier effect of the Channel and potentially of the Mediterranean Sea on R. ferrumequinum bat dispersal. Conversely, we could not reveal any gene flow disruption from both sides of the Western Pyrenees. These results provide important information to improve the delineation of R. ferrumequinum management units in its western range. We suggest that a large management unit corresponding to the European mainland population must be considered. Particular attention should be given to mating territories as they seem to play a key role in maintaining the high levels of genetic mixing between colonies. Smaller management units corresponding to English and Northern France colonies must also be implemented. These insular or peripheral colonies could be at higher risk of extinction in a near future.

evolutionary biology↗