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Vegetation structure drives mosquito community composition in UK’s largest managed lowland wetland
Get PDFPurpose
The rising burden of mosquito-borne diseases in Europe extends beyond urban areas, encompassing rural and semi-urban regions near managed and natural wetlands evidenced by recent outbreaks of Usutu and West Nile viruses. While wetland management policies focus on biodiversity and ecosystem services, few studies explore the impact on mosquito vectors.
Methods
Our research addresses this gap, examining juvenile mosquito and aquatic predator communities in 67 ditch sites within a South England coastal marsh subjected to different wetland management tiers. Using joint distribution models, we analyse how mosquito communities respond to abiotic and biotic factors influenced by wetland management.
Results
Of the 12 mosquito species identified, Culiseta annulata (Usutu virus vector) and Culex pipiens (Usutu and West Nile virus vector) constitute 47% of 6825 larval mosquitoes. Abundant predators include Coleoptera (water beetles) adults, Corixidae (water boatmen) and Zygoptera (Damselfy) larvae. Models reveal that tier 3 management sites (higher winter water levels, lower agricultural intensity) associated with shade and less floating vegetation are preferred by specific mosquito species. All mosquito species except Anopheles maculipennis s.l., are negatively impacted by potential predators. Culiseta annulata shows positive associations with shaded and turbid water, contrary to preferences of Corixidae predators.
Conclusions
Tier 3 areas managed for biodiversity, characterised by higher seasonal water levels and reduced livestock grazing intensity, provide favourable habitats for key mosquito species that are known vectors of arboviruses, such as Usutu and West Nile. Our findings emphasise the impact of biodiversity-focused wetland management, altering mosquito breeding site vegetation to enhance vector suitability. Further exploration of these trade-offs is crucial for comprehending the broader implications of wetland management
An update on the ecology, seasonality and distribution of Culex modestus in England
Get PDFCulex (Barraudius) modestus is an important vector of West Nile virus (WNV) in Europe and it has the potential to play a bridge vector role in future WNV transmission in the UK. Here we provide an update on the known distribution of the species in England based on adult and larval data, characterise the preferred Cx. modestus larval habitats, and present adult and larval data from sites where the species is known to occur. Culex modestus is primarily found in the south-east of England, particularly in North Kent, the Thames Estuary, and along the Essex coast, and as far east as Orford Ness, Suffolk, and in Rainham Marshes, Essex, in the West. Adult numbers peak in mid-late July, with larval numbers highest in late August / early September. Preferred habitats in North Kent are warm, shallow, narrow ditches, with an abundance of marginal, submerged, and floating vegetation. Such environmental data on the distribution, seasonality and habitat preference of Cx. modestus are critical for informing WNV surveillance programmes, identifying at risk areas (associated with this species) and providing information for a targeted control strategy in the event of WNV transmission
The effect of preferential associations on the reproductive performance of group-housed sows
Get PDFThe investigation of social bonds as a measure to improve reproduction in farmed species is an underrepresented research area. This study investigated the effects of preferential associations between group housed sows (average herd size, n = 59) on stillborn and crushed piglet numbers. Preferential associations were described as resting within 60 s. The study occurred over 63 consecutive days, broken down into three 21-day periods referred to as cycles. The 21-day cycles represent the time between reintegrating events. Seven days per cycle were selected for observations providing 63 h of footage covering the functional areas of the barn. Production data were taken from one farrowing that occurred after a sow had been transferred from the barn to the farrowing house during the study period. For group-level analysis, the sows were categorised as socially prominent or non-socially prominent. Social prominence is defined as an individual that engages in significantly higher levels of interactions than their sub-group conspecifics. The subgroups were determined by our previous work that identified assortment by social connectivity within the same study herd. Each subgroup was defined as a k-core, in which the k-value represents the level of connectivity of those in the group (i.e., subgroup K1 means sows are connecting with at least one other conspecific). For individual-level analysis, sows were categorised as a sow with stillborn (at least one stillborn piglet) or a sow without stillborn (no stillborn piglets) and as a crushing sow (at least one crushed piglet) or a non-crushing sow (no crushed piglets). Degree centrality was applied to determine the number of interactions that individuals initiated and received. Results showed no overall effects of social prominence on live-born piglets (p = 0.436). Socially prominent sows demonstrated a lower mean rate of stillborn than non-socially prominent sows. Sows with stillborn had significantly lower degree centrality than sows without stillborn (p < 0.05). The numbers of crushed piglets between socially prominent and non-socially prominent sows were variable with crushing sows demonstrating significantly higher degree centrality than non-crushing sows (p < 0.05). Overall, the evidence does not provide a clear relationship between social prominence during gestation and the reproductive outputs of sows. Therefore, further work is required to validate the effects of social position in affiliative networks on the production indices of farmed pigs
The determinants of MNE foreign subsidiaries' performance: a systematic literature review and future research agenda
Get PDFPurpose: Foreign subsidiaries of multinational enterprises (MNEs) operate in complex and competitive international environments, implement market and non-market strategies, manage resources and value-added activities, and contribute to the overall performance of their parent firms. Thus, the research question on the determinants of MNE foreign subsidiaries’ performance is of interest to managers and academic researchers. The empirical literature has flourished over the recent decades; however, the domains are fragmented, and the findings are inclusive. The purpose of this study is to systematically review, analyse, and synthesize the empirical articles in this area, identify research gaps, and suggest a future research agenda.
Design/ methodology/ approach: This study uses the qualitative content analysis method in reviewing and analysing 150 articles published in 24 scholarly journals during the period 2000-2023.
Findings: The literature uses a variety of theoretical perspectives to examine the key determinants of subsidiary performance which can be grouped into six major domains, namely, home and host country level factors; distance between home and host countries; the characteristics of parent firms and of subsidiaries; governance mechanisms (the establishment modes and ownership strategy, subsidiary autonomy, and the use of home country expatriates for transferring knowledge from the headquarters and controlling foreign subsidiaries). A range of objective and subjective indicators are used to measure subsidiary performance. Yet, the research shows a lack of broader integration of theories, presents inconsistent theoretical predictions, inconclusive empirical findings, and estimation bias, which hinder our understanding how the determinants independently and jointly shape the performance of foreign subsidiaries.
Originality/value: This study provides a comprehensive, nuanced, and systematic review that synthesizes and clarifies on the determinants of subsidiary performance, offers deeper insights from both theoretical, methodological, and empirical aspects, and proposes some promising avenues for future research directions
The glc locus of Campylobacter jejuni
No full textCampylobacter jejuni, the major cause of bacterial gastroenteritis, is widespread in
farmyard animals and poultry. The main source of human disease is through the food
chain, often through contaminated chickens, but C. jejuni and C. coli are also present in
the environment. C. jejuni is a strict microaerophile with an essentially asaccharolytic
metabolism. These bacteria are naturally competent, allowing uptake of naked DNA from
lysed cells, which contributes to enhanced genome variation and potentially ability to
survive in varied environments and niche adaptation. This study has focused on the
unusual ability of some C. jejuni and C. coli strains to metabolise glucose via the Entnerdouderoff (ED) pathway with an aim of shedding light on the benefit of possession of the
glc locus by a subset of ‘environmental’ strains.
Addition of glucose to minimal media, DMEMf, had no impact on exponential growth
but prevented rapid decline in viability of C. jejuni Dg275 from 24 h. Reverse
transcription- quantitative polymerase chain reaction (RT-qPCR) demonstrated a 7-8 fold
increase in expression of edd and zwf (encoding enzymes of the ED pathway) and a small
but significant increase in glcP (encodes glucose transporter) between late exponential
(18 h) to stationary phase (24 h), correlating with initiation of glucose utilisation. cDNA
PCR analysis across gene junctions of transcripts and promoter predictions provided
preliminary evidence of a working map of this divergent seven gene glc locus. Ribosomal
(r)MLST and core genome (cg)MLST highlighted phylogenetic clustering of glc positive
C. jejuni strains close to but distinct from glc negative ST45CC45 strains isolated from Norway rats. Further comparisons of available genome sequences revealed that most
glycolytic C. jejuni and C. coli strains, also carried the fuc locus encoding genes for
fucose metabolism. In DMEMf with glucose and fucose, growth of Dg275 followed the
characteristic diauxic profile of growth on fucose, indicating fucose as a preferred
substrate. Deletion of fucR, encoding the FucR repressor, together with the main fuc
regulatory region, in Dg275ΔfucR::cat, indicated that loss of FucR regulator and products
of fucose metabolism did not impact glucose-driven growth, but that in the wild-type
Dg275 either FucR or products of fucose metabolism somehow represses the
characteristic glucose promoted survival.
Although assumed to occur, transfer of the glc locus between C. jejuni strains, in vitro,
has never been demonstrated. Attempts to transfer the glc locus, via natural
transformation, from genomic DNA of the glycolytic Dg275 strain to the related nonglycolytic strain, Dg200, were unsuccessful. The presence of duplicate copies of the glc
locus, one within rrnA and the other within rrnB complicated construction of isogenic
knockout mutant and wild-type strains. Ultimately, the mutated strains
Dg275ΔglcP::KANrrnAΔglcP::catrrnB (Dg275ΔglcP) and
Dg275Δedd::KANrrnAΔedd::catrrnB (Dg275Δedd) were created in two steps. Hybrid
genome sequencing was used to confirm sequences of single and double knockout
mutants. While inactivation of both copies of the genes resulted in the inability to grow
on glucose, possession of a single functional copy of glcP or edd, was shown to be
sufficient for glucose utilisation and enhanced survival. These results and knockout
mutants will provide the foundation and tools for future studies to further investigate control of expression and function of the glc locus with a view to understanding the
significance of the Campylobacter glc locus to niche adaptation
Surprise floods: the role of our imagination in preparing for disasters
Get PDFWhat’s the worst that could happen? After a flood
has devastated communities, those affected, the news media, and the authorities often say that what happened was
beyond our imagination. Imagination encompasses the picturing of a situation in our minds linked with the emotions that we connect to this situation. However, the role imagination actually plays in disasters remains unclear. In this regard, we analysed the responses of a survey that was disseminated in the 2021-flood-affected areas of Germany. Some respondents perceived that due to their lack of imagination regarding the flood, they did not take adequate action in advance. Limited or a lack of imagination could be linked to never having experienced a flood before, difficulties in interpreting forecasts and warnings, the perceived distance to waterbodies, and cognitive biases. Overall, the responses indicated the influence of imagination on risk perception. Based
on these results, we recommend that future research should
investigate the extent to which visual support can help forecast and warning communication to trigger the imagination of citizens in the short-term. From a long-term perspective, research should focus on how to cultivate imagination over time through participatory risk management, developing climate storylines, citizen weather observations, and the like
Beckett’s romantic imagination
No full textBeckett scholarship has, on the whole, neglected to probe whether there is anything deeper at
work behind the persistent references to Romanticism in Beckett’s writing, preferring instead
to follow the general consensus that it barely operates on the periphery of Beckett’s creative
practice. Yet ‘still today, when I walk there, I find its vestiges’,1 vestiges which prove vital to
casting new light on how and why Beckett wrote the way he did, in structural and formal as
well as thematic terms. In 2004, C. J. Ackerley and S. E. Gontarski noted that a ‘good study of
the Romantic impulse in SB’s writings, revealing unexpected insights into a tradition
vehemently rejected but never quite denied, is currently lacking’.2 Three years later, Dirk Van
Hulle and Mark Nixon, editing the special issue to Samuel Beckett Today / Aujourd’hui
dedicated to Beckett and Romanticism, wrote that the issue ‘tries to give an impetus to the
study of this complex theme’.3 Enoch Brater reiterated the call again in 2011: ‘Yet how Beckett
liberates himself from parody to confront the romanticism inherent in his own “profounds of
mind” is a story of artistic maturity still waiting to be told’.4 This thesis attempts to answer
these calls in a way which discovers Beckett’s Romanticism not as counterintuitive to his
poetics of the unsaid but rather as directly connected to it. His Romanticism plays a central role
in his artistic maturity into minimalism and silence
BIM in the Malaysian construction industry: a scientometric review and case study
Get PDFPurpose – The purpose of this study is to explore existing literature on Building Information Modelling (BIM)
in Malaysia and examine the perception of practitioners about the potential of BIM applications in reducing
construction waste and enhancing productivity.
Design/methodology/approach – First, using 244 bibliographic data extracted from the Scopus database,
the paper used scientometric analysis and VOSviewer mapping technique to assess the most impactful
publication literature on BIM in Malaysia to identify the existing research gaps. Second, using a structured
questionnaire, a total of 100 questionnaires were distributed to practising practitioners who incorporate BIM in
the delivery of their projects. Descriptive analysis using cross-tabulation in SPSS software, radar chart, relative
importance index and Pearson’s correlation were used to analyze the data.
Findings – The research gaps are in the fields of construction projects, buildings, energy efficiency, lifecycle
and housing. The findings of the survey indicate that quantity take-off, clash detection, site utilization
planning, digital fabrication as well as 4D stimulation were the main BIM applications used among the
practitioners in Johor and Selangor.
Practical implications – By assessing the state-of-the-art of BIM and BIM applications in this region, the
practical implications of this study provide useful insights to construction stakeholders, funding organizations,
policymakers, research institutions, professionals, journal editors, reviewers and researchers to understand the
overall trend of BIM in Malaysia and its usage.
Originality/value – This paper is the first to use science mapping using scientometrics to reveal the current
BIM research in “Malaysia only”. Relying on the identified gaps, the study further examined the usage of BIM
applications in Malaysian construction projects
Learning to live with an unruly consuming body
No full textPast research shows that successful consumer learning takes place in environments that support cooperative communities of practice, that enable access to refined didactic resources, and that provide a safe, sympathetic backstage for a controllable and able learning body to durably transition from one repertoire to another. This study complements existing research by investigating a group of lactose-intolerant consumers who must learn to transition to a new consumption repertoire because of socially embarrassing symptoms. Consumers must engage in high-risk, unguided, experiential learning pathways in a less than sympathetic frontstage, without the support of a cooperative community or a well-developed vocabulary, and while grappling with an impaired and unruly body in a dynamic marketplace. The findings demonstrate that consumers adapt to this hostile learning environment by surfing between different consumption repertoires in a fluid, impermanent manner
Strong surface winds in Storm Eunice. Part 1: storm overview and indications of sting-jet activity from observations and model data
Get PDFStorm Eunice caused severe wind impacts on the UK on 18 February 2022. This article
contains the first of a two-part study and shows how Eunice’s cyclone structure was well
forecast days in advance, but small-scale uncertainty persisted on peak-wind location
and strength. Several indications of sting-jet (SJ) activity in observations and model
data are presented. The detailed analysis of Eunice’s airstream structure is left to the
second part of this study