Integrative taxonomy of Afrotropical Ornithodoros (Ornithodoros) (Acari: Ixodida: Argasidae)

Afrotropical Ornithodoros (Ornithodoros) ticks are revised based on qualitative morphology of females and nymphs, as well as tarsus I shape outlines of females measured in a geometric morphometric framework. These lines of evidence corroborate lineages based on 16S rRNA nucleotide sequence data. Four previously unrecognized species are described, along with a revived nomen nudum that was previously considered a synonym. Afrotropical Ornithodoros (Ornithodoros) now comprise ten species. Ornithodoros moubata and Ornithodoros porcinus are separated from three other species in southern Africa (Ornithodoros compactus, Ornithodoros phacochoerus n. sp., Ornithodoros waterbergensis n. sp.), with O. porcinus restricted to central east Africa. Known species boundaries for Ornithodoros apertus and O. compactus are supported. Ornithodoros savignyi are separated from three other species in South Africa and Namibia, with O. savignyi restricted to north Africa. Neumann’s Ornithodoros pavimentosus nom. rev. are resurrected from synonymy as a species that occur in Bushmanland, Namaqualand and Namibia, while Ornithodoros kalahariensis n. sp. occur in Kalahari thornveld, and Ornithodoros noorsveldensis n. sp. occur in Noorsveld thicket of South Africa. Detailed descriptions are given for each species along with high resolution images and point map distributions. Support is provided for speciation driven by riverine barriers, Pliocene uplift and differential arid tolerance. Exaggerated tarsus I shape in the O. savignyi group suggests adaptation to fossorial habits and soil type. Conversely, reduced tarsus I shape in the O. moubata group is suggested as an evolutionary consequence of the life history change from soil to warthog burrows. This study represents an integrative (iterative) approach to delimiting Afrotropical Ornithodoros (Ornithodoros) species, and provides the first application of tarsus I shape outlines in a geometric morphometric framework for testing species boundaries.The Department of Science and Technology (DST) , National Assets Budget allocated to the Gertrud Theiler Tick Museum , the Economic Competitive Support Programme (30/01/V010) and the National Research Foundation (NRF) Incentive Funding for Rated Researchers (NRF-Mans) .http://www.elsevier.com/locate/ttbdis2019-05-01hj2019Veterinary Tropical Disease

Easy and rapid purification of highly active nisin

Nisin is an antimicrobial peptide produced and secreted by several L. lactis strains and is specifically active against Gram-positive bacteria. In previous studies, nisin was purified via cation exchange chromatography at low pH employing a single-step elution using 1 M NaCl. Here, we describe an optimized purification protocol using a five-step NaCl elution to remove contaminants. The obtained nisin is devoid of impurities and shows high bactericidal activity against the nisin-sensitive L. lactis strain NZ9000. Purified nisin exhibits an IC 50 of ∼3 nM, which is a tenfold improvement as compared to nisin obtained via the one-step elution procedure

Genetic fusion of P450 BM3 and formate dehydrogenase towards self-sufficient biocatalysts with enhanced activity

Fusion of multiple enzymes to multifunctional constructs has been recognized as a viable strategy to improve enzymatic properties at various levels such as stability, activity and handling. In this study, the genes coding for cytochrome P450 BM3 from B. megaterium and formate dehydrogenase from Pseudomonas sp. were fused to enable both substrate oxidation catalyzed by P450 BM3 and continuous cofactor regeneration by formate dehydrogenase within one construct. The order of the genes in the fusion as well as the linkers that bridge the enzymes were varied. The resulting constructs were compared to individual enzymes regarding substrate conversion, stability and kinetic parameters to examine whether fusion led to any substantial improvements of enzymatic properties. Most noticeably, an activity increase of up to threefold was observed for the fusion constructs with various substrates which were partly attributed to the increased diflavin reductase activity of the P450 BM3. We suggest that P450 BM3 undergoes conformational changes upon fusion which resulted in altered properties, however, no NADPH channeling was detected for the fusion constructs

Cognitive agents for microscopic traffic simulations in virtual environments

Traffic simulations in current open world video games and driving simulators are still limited with respect to the complexity of the behavior of simulated agents. These limitations are typically due to scarce computational resources, but also to the applied methodologies. We suggest adding cognitive components to traffic agents in order to achieve more realistic behavior, such as opting for risky actions or occasionally breaking traffic rules. To achieve this goal, we start by adding a personality profile to each agent, which is based on the “Five Factor Model” from psychology. We test our enhancement on a specific traffic scenario where simplistic behaviors would lead to a complete standstill of traffic. Our results show that the approach resolves critical situations and keeps traffic flowing

Integrative taxonomy and species delimitation of Rhipicephalus turanicus (Acari: Ixodida: Ixodidae)

Rhipicephalus turanicus ticks are widely distributed across the Palearctic and Afrotropics. These two continental populations display differences in morphological characters that raise the question of a potential species boundary. However, the taxonomic status of these morphologically divergent lineages is uncertain because R. turanicus from Cyprus and Zambia have been shown to interbreed and produce fertile hybrids. We employ integrative taxonomy that considers data from mtDNA sequences (12S and 16S rDNA), geographic distribution, traditional (qualitative) morphology, as well as shape outlines of female spiracles and male adanal plates measured in a geometric morphometric framework (quantitative morphology) to resolve this taxonomic issue. Molecular lines of evidence (12S and 16S rDNA) support taxonomic separation between ticks sampled in the Afrotropics and the Palearctic. This is corroborated by qualitative and quantitative morphology. Within the Palearctic, two sub-lineages were recovered based on sequence data that loosely correspond to southern Europe and the Middle East/Asia. One new species, Rhipicephalus afranicus n. sp. is described from South Africa with a geographic distribution that extends into eastern Africa. This leaves R. turanicus sensu lato comprised of two lineages located in southern Europe and the Middle East/Asia. The type locality for R. turanicus is in Uzbekistan, thus the Middle East/Asia lineage is considered R. turanicus sensu stricto. Detailed descriptions are provided for R. afranicus n. sp. and R. turanicus sensu stricto together with high resolution images. Speciation is attributed to recent Sahara desert expansion that formed a natural barrier to dispersal approximately 5–7 million years ago. However, reproductive potential between these two species suggests that divergence time and mode of speciation were not sufficient for the development of reproductive isolation. We suggest speciation was complicated by divergence and population reintegration events driven by oscillating climatic conditions contributing to reticulate evolution and maintenance of compatibility between reproductive mechanisms. This study represents an integrative (iterative) approach to delimiting Rhipicephalus spp., and provides the first application of shape outlines for female spiracles and male adanal plates measured in a geometric morphometric framework, applied to testing species boundaries between ticks.Data for "Integrative Taxonomy and Species Delimitation of Rhipicephalus turanicus (Acari: Ixodida: Ixodidae)". Description: This work tests the species boundary between Afrotropical and Palearctic R. turanicus ticks. We show that molecular divergence and morphological differences are distinct and warrant separate species status. The dataset includes 1) alignments for 12S and 16S rDNA as well as the concatenated molecular dataset with MrBayes script, and 2) morphometric landmark data for male adanal plates and female spiracles as well as the photographs of these features. Available at https://data.mendeley.com/datasets/zjmtx7ghx4/1Supplementary Files: Figure S1. Operational definitions for landmarks.Figure S2. Fully labelled phylogenetic splits tree analysis of the 12S rDNA gene using TN+F+G4 nucleotide substitution model. Indicated are species and lineage names, GenBank accessions or study codes (reflected in Table S1), country of origin and neighbour network bootstrap support values. Bolded samples were used iteratively in morphometric analysis.Figure S3. Fully labelled phylogenetic splits tree analysis of the 16S rDNA gene using TPM3u+F+G4 nucleotide substitution model. Indicated are species and lineage names, GenBank accessions or study codes (reflected in Table S1), country of origin and neighbour network bootstrap support values. Bolded samples were used iteratively in morphometric analysis.Table S1. Material examined in this study.The Department of Science and Technology (DST), National Assets Budget allocated to the Gertrud Theiler Tick Museum, South Africa.http://www.elsevier.com/locate/ijpara2021-07-01hj2020Veterinary Tropical Disease

Adaptive radiation and speciation in Rhipicephalus ticks: a medley of novel hosts, nested predator-prey food webs, off-host periods and dispersal along temperature variation gradients

Rhipicephalus are a species-diverse genus of ticks, mainly distributed in the Afrotropics with some species in the Palearctic and Oriental regions. Current taxonomic consensus comprise nine informal species groups/lineages based on immature morphology. This work integrates biogeographic, ecological and molecular lines of evidence to better understand Rhipicephalus evolution. Phylogenetic analysis based on four genes (12S, 16S, 28S-D2 and COI) recovered five distinct clades with nine descendant clades that are generally congruent with current taxonomy, with some exceptions. Historical biogeography is inferred from molecular divergence times, ancestral distribution areas, host-use and climate niches of four phylogenetically significant bioclimatic variables (isothermality, annual, seasonal and diurnal temperature range). Novel hosts enabled host-linked dispersal events into new environments, and ticks exploited new hosts through nested predator-prey connections in food webs. Diversification was further induced by climate niche partitioning along gradients in temperature range during off-host periods. Ancestral climate niche estimates corroborated dispersal events by indicating hypothetical ancestors moved into environments with different annual and seasonal temperature ranges along latitudinal gradients. Host size for immature and adult life stages was important for dispersal and subsequent diversification rates. Clades that utilise large, mobile hosts (ungulates and carnivores) early in development have wider geographic ranges but slower diversification rates, and those utilising small, less mobile hosts (rodents, lagomorphs and afroinsectivores) early in development have smaller ranges but higher diversification rates. These findings suggest diversification is driven by a complex set of factors linked to both host-associations (host size, ranges and mobility) and climate niche partitioning along annual and seasonal temperature range gradients that vary with latitude. Moreover, competitive interactions can reinforce these processes and drive speciation. Off-host periods facilitate adaptive radiation by enabling host switches along nested predator-prey connections in food webs, but at the cost of environmental exposure that partitions niches among dispersing progenitors, disrupting geneflow and driving diversification. As such, the evolution and ecological niches of Rhipicephalus are characterised by trade-offs between on- and off-host periods, and these trade-offs interact with nested predator-prey connections in food webs, host-use at different life stages, as well as gradients in annual and seasonal temperature ranges to drive adaptive radiation and speciation

Evolution of lacewings and allied orders using anchored phylogenomics (Neuroptera, Megaloptera, Raphidioptera)

Analysis of anchored hybrid enrichment (AHE) data under a variety of analytical parameters for a broadly representative sample of taxa (136 species representing all extant families) recovered a well-resolved and strongly supported tree for the higher phylogeny of Neuropterida that is highly concordant with previous estimates based on DNA sequence data. Important conclusions include: Megaloptera is sister to Neuroptera; Coniopterygidae is sister to all other lacewings; Osmylidae, Nevrorthidae and Sisyridae are recovered as a monophyletic Osmyloidea, and Rhachiberothidae and Berothidae were recovered within a paraphyletic Mantispidae. Contrary to previous studies, Chrysopidae and Hemerobiidae were not recovered as sister families and morphological similarities between larvae of both families supporting this assumption are reinterpreted as symplesiomorphies. Relationships among myrmeleontoid families are similar to recent studies except Ithonidae are placed as sister to Nymphidae. Notably, Ascalaphidae render Myrmeleontidae paraphyletic, again calling into question the status of Ascalaphidae as a separate family. Using statistical binning of partitioned loci based on a branch-length proxy, we found that the diversity of phylogenetic signal across partitions was minimal from the slowest to the fastest evolving loci and varied little over time. Ancestral character-state reconstruction of the sclerotization of the gular region in the larval head found that although it is present in Coleoptera, Raphidioptera and Megaloptera, it is lost early in lacewing evolution and then regained twice as a nonhomologous gula-like sclerite in distantly related clades. Reconstruction of the ancestral larval habitat also indicates that the ancestral neuropteridan larva was aquatic, regardless of the assumed condition (i.e., aquatic or terrestrial) of the outgroup (Coleopterida)

Ambient monitoring from an elderly-centred design perspective: what, who and how

This paper describes a participatory design-oriented study of an ambient assisted living system for monitoring the daily activities of elderly residents. The work presented addresses these questions 1) What daily activities the elderly participants like to be monitored, 2) With whom they would want to share this monitored data and 3) How a monitoring system for the elderly should be designed. For this purpose, this paper discusses the study results and participatory design techniques used to exemplify and understand desired ambient-assisted living scenarios and information sharing needs. Particularly, an interactive dollhouse is presented as a method for including the elderly in the design and requirements gathering process for residential monitoring. The study results indicate the importance of exemplifying ambient-assisted living scenarios to involve the elderly and so to increase acceptance and utility of such systems. The preliminary studies presented show that the participants were willing to have most of their daily activities monitored. However, they mostly wanted to keep control over their own data and share this information with medical specialists and particularly not with their fellow elderly neighbours