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Colonising Disability: Impairment and Otherness Across Britain and Its Empire, c. 1800-1914, by Esme Cleall; pp. xi + 299. Cambridge: Cambridge University Press, 2022, 67.00 [pound sterling], $114.95, $99.99 ebook. [...]

ABSTRACT In long‐distance dispersal events, colonising species typically begin with a small number of founding individuals. A growing body of research suggests that establishment success of small founding populations can be determined by the context of the colonisation event and the new environment. Here, we illuminate the importance of these sources of context dependence. Using a spatially explicit, temporally dynamic, mechanistic, individual‐based simulator of a model amphibian species, the cane toad (Rhinella marina), we simulated colonisation scenarios to investigate how (1) the number of founding individuals, (2) the number of dispersal events, (3) landscape's spatial composition and configuration of habitats (‘spatially heterogeneous landscapes’) and (4) the timing of arrival with regards to dynamic environmental conditions (‘dynamic environmental conditions’) influence the establishment success of small founding populations. We analysed the dynamic effects of these predictors on establishment success using running‐window logistic regression models. We showed establishment success increases with the number of founding individuals, whereas the number of dispersal events had a weak effect. At ≥ 20 founding individuals, propagule size swamps the effects of other factors, to whereby establishment success is near‐certain (≥ 90%). But below this level, confidence in establishment success dramatically decreases as number of founding individuals decreases. At low numbers of founding individuals, the prominent predictors are landscape spatial heterogeneity and dynamic environmental conditions. For instance, compared to the annual mean, founding populations with ≤ 5 individuals have up to 18% higher establishment success when they arrive in ‘packed’ landscapes with relatively limited and clustered essential habitats and right before the breeding season. Accounting for landscape spatial heterogeneity and dynamic environmental conditions is integral in understanding and predicting population establishment and species colonisation. This additional complexity is necessary for advancing biogeographical theory and its application, such as in guiding species reintroduction efforts and invasive alien species management.

ABSTRACT Faba bean can be infected by Pea necrotic yellow dwarf virus (PNYDV), a novel pathogen throughout Europe, and transmitted persistently by several legume‐colonising aphid species. Recent field screenings in Austria and Germany of different faba bean varieties were encouraging as consistently the lowest viral symptom development in the variety ‘GL Sunrise’ was reported. However, our own greenhouse experiments revealed that ‘GL Sunrise’ was not resistant to PNYDV but showed a similar susceptibility such as other common varieties, for example, ‘Fuego’. Therefore, we suspected varietal host traits were affecting the reproductive potential of virus vector species with reduced virus transmission, probably explaining the empirical superior health status in the field. Under greenhouse conditions, vector‐specific intrinsic rates of increase (rm) for Acyrthosiphon pisum Harris Aphis fabae Scopoli and Megoura viciae Buckton were similar for both varieties, except for a particular A. pisum‐biotype derived from field pea, with a significantly reduced rm and fecundity in ‘GL Sunrise’. Furthermore, vector abundance assessments in multisite varietal showed A. pisum as the predominant species. In overall cross‐year and ‐site evaluation, early aphid census in ‘GL Sunrise’ at growth stage BBCH 61–65 indicated significantly lower primary A. pisum‐infestation pressure (factor 0,43 relative to ‘Fuego’). This lower infestation level in ‘GL Sunrise’ was kept until BBCH 77–79 but the difference had diminished down to the non‐significant factor of 0,74 A. pisum‐density relative to ‘Fuego’ in the late census, respectively. Based on our findings of (i) basic PNYDV susceptibility, (ii) similar reproductive vector performance of key aphid species, together with (iii) a significantly weaker initial A. pisum‐infestation levels in the field, we hypothesise ‘GL Sunrise’‐specific additional antixenosis/antibiotic traits, must influence host recognition and settling behaviour of alighting (viruliferous) migrants and/or apteres, which finally determine the superior PNYDV‐health status in ‘GL Sunrise’ at field conditions. [ABSTRACT FROM AUTHOR]

Pectobacterium atrosepticum (Pba) is a gram-negative bacterium that causes blackleg and tuber soft rot of potato but can also asymptomatically colonise other (non-host) plant species. The aim of this study was to investigate the molecular processes and responses involved in Pba-host (potato) and Pba-non-host (radish) interactions, under laboratory conditions. To achieve this, we used total mRNA-sequencing to measure the gene expression patterns from all three species: Pba, potato and radish. We employed an end-point dual transcriptome approach. We used hydroponically grown potato (Solanum tuberosum var. Estima) and oil radish (Raphanus sativa var. Bento) roots inoculated with Pba SCRI1039 for 14 days compared to un-inoculated control plants or cultured bacteria. Total RNA was extracted from replicates of the two plant species and the bacterium using a Macherey-Nagel Nucleospin Plant RNA kit. The RNA from the 17 samples was then subjected to total mRNA-sequencing (paired-end) on an Illumina NovaSeq 6000™ sequencing platform. This gave between 39.2-58.1M reads per sample. The high-quality reads obtained were mapped to the corresponding reference genomes using Bowtie2 and the percentages of bacterium and plant transcripts calculated. This dataset constitutes the raw read fastq files and can be used to inform on genes active in plant rhizosphere-microbe interactions.

Purpose – The British East India Company (EIC) made connections between the Malay Archipelago and Bengal and established a penal settlement at Bencoolen, followed by the Straits Settlements for the Indian convicts. The convicts from different parts of South Asia today were generally described as “Indian”, such generalisation often hides the identity of specific convicts from South Asia. Among the Indian convicts, the Bengalis were transported to Bencoolen and the Straits Settlements. However, the generic term has made it difficult to reconstruct the history of Bengali convicts’ experiences and pathos. Therefore, this paper attempts to “rediscover” the afterlife of transportation of Bengali felons in the Malay Peninsula. Design/methodology/approach – By examining a range of archival records and current scholarships, this article shows the inclusivity, diversity and accessibility of convict labourers with mainstream society. This study will open up a new avenue of convict histories and subaltern studies on Asia. Findings – The Bengali convicts in the Straits Settlements, one of the oldest migrant sections, have largely been ignored in historical literature. Though the Bengalis, among other South Asian convicts, constituted a significant portion, they were categorised under the generic term “Indian” (Rai, 2014). Their manual labour was invaluable for the colonial economy and the development of the Straits Settlements. Research limitations/implications – Researcher faced difficulties to get the descendant of Bengali convicts. Originality/value – This article is a research paper based on mostly archival records; therefore, it is an original contribution to the existing knowledge on the convict history.

The uniqueness of Wallachian settlement in the territories of Poland was that it extended beyond its natural mountain and submontane zone. This resulted in the emergence of settlements founded under Wallachian law, including the Sandomierz Forest area. The aim of the article is to examine the economic activity of the residents of these settlements, which was conditioned by the environmental situation. One important problem addressed in this work is the question of reasons for the colonisation backwardness in this region, manifested in the slow pace of the progress of urbanisation, the limited scope of the money economy, and the late development of manorial demesnes, among other factors. These delayed and poorly discernible processes were followed by the evolution of the profile of Wallachian-law settlements, evident in the 16th century. The permeation of elements of Wallachian customs into agricultural settlements was an important adaptation element that has not been properly examined in the literature.

Microplastics quickly become colonised by diverse microbial communities, known as the Plastisphere. There is growing concern that microplastics may support the enrichment and spread of pathogenic or antimicrobial resistant microorganisms, although research to support the unique role of microplastics in comparison to control particles remains inconclusive. Limitations to this research include the microbiological methods available for isolating adhered microbes. Culture-based methods provide some of the most established, accessible and cost-effective microbiological protocols, which could be extremely useful in helping to address some of the remaining key questions in Plastisphere research. Previous works have successfully cultured bacteria from plastics, but these have not yet been reviewed, nor compared in efficiency. In this study, we compared four common biofilm extraction methods (swabbing, sonication, vortexing, sonication followed by vortexing) to extract and culture a mixed community of bacteria from both microplastic (polyethylene, polypropylene and polystyrene) and control (wood and glass) particles. Biofilm extraction efficiency and viability of bacterial suspension was determined by comparing CFU/mL of four different groups of bacteria. This was verified against optical density and 16S rRNA qPCR. Overall, we found that all tested methods were able to remove biofilms, but to varying efficiencies. Sonicating particles with glass beads for 15 min, followed by vortexing for a further minute, generated the highest yield and therefore greatest removal efficiency of culturable, biofilm-forming bacteria.