On the Tayassuid affinities of Xenohyus Ginsburg, 1980, and the description of new fossils from Spain

In 1980, Ginsburg created the new genus Xenobyus for a large suiform artiodactyl which he considered to belong to the family Suidae. Among the distinguishing characters of the genus, Ginsburg cited the enlarged, strongly curved and inflated central upper incisors possessing a distal accessory cusplet, the shortened muzzle, the enlarged lower first and second incisors, and the c10se packing of the entire tooth row (i.e. reduced to absent diastemata). These and other characters, such as the vertically implanted mandibular canines, the sympbyseal morphology, and the shape of the third upper incisor, suggest that Xenobyus belongs instead to the family Tayassuidae, subfamily Doliochoerinae. Whereas Ginsburg suggested that Xenobyus had an unknown ancestry and that it represented an immigrant into Europe at about the beginning of zone MN2b, it now seems more likely that it represents a late doliochoere of the sort represented by Doliochoerus quercyi which occurs in late Stampian deposits (Ginsburg, 1974). In many ways it is merely an enlarged version of this species, but there are sufficient morphological differences to warrant retention of the genus Xenobyus. Viewed within a tayassuid framework, Xenobyus is not seen to be unusual and not to run counter to evolutionary trends in the Suidae, the latter view being a necessity following its identifiation as a suid. Sorne fundamental similarities between tbe molars of Xenobyus and Kenyapotamus could provide a link between late doliochoeres and early hippopotamids, an hypothesis already mentioned by Pickford (1983). Newly discovered fossils from Loranca, Cuenca, Spain belong to two different species of Xenobyus, X venitor and an undescribed larger species. Nuevos fósiles, descubiertos en Loranca (Cuenca, España), pertenecientes a dos diferentes especies de Xenobyus; X vemtor y Xenobyus sp. de talla mayor que el anterior, son también descritos en este trabajo.Ginsburg (1980) creó un nuevo género Xenobyus para un suiforme de talla grande que consideró como perteneciente a la familia Suidae. Entre los caracteres que distinguían a este nuevo género, Ginsburg citaba la morfología peculiar del tercer incisivo superior; ensanchado, fuertemente curvado, centralmente hinchado y con un tubérculo accesorio distal. Así como el acortamiento del morro, los incisivos inferiores (I1 e I2) y la ausencia en la serie dentaria de diastemas. Este y otros caracteres, como son la implantación vertical de los caninos en la mancUbula, la morfología sinfisaria, y la forma del tercer incisivo superior, sugieren que Xenobyus pertenece más bien a la familia Tayassuidae, subfamilia Doliochoerinae. Para Ginsburg, Xenobyus no tenía ningún ancestro conocido en Europa y por tanto, debía ser un inmigrante, cuya entrada se habría producido cerca de los comienzos de la unidad NM2b. Xenobyus es ahora visto como uno de los últimos miembros de los doliochoerinos, representados por Doliochoerus quercyi en los depósitos del Estampiense superior (Ginsburg, 1974). De alguna manera, Xenobyus es meramente una versión agrandada de esta especie, pero hay suficientes diferencias morfológicas que apoyan la retención del género. Algunas similaridades fundamentales entre los molares de Xenobyus y Kenyapotamus podrían probar una relación entre los últimos doliochoerinos y los primeros hipopótamos, hipótesis ya ciertamente mencionada por Pickford (1983)

The last African metatherian

Funding Information: F.J.G. and V.D.C. thank Agencia (Foncyt, Mincyt; PICT 2019-03283) and CONICET (PIP KB2 - 11220200100150CO). Funding Information: We thank the Uganda Museum, Kampala (Rose Mwan-ja, Sarah Musalizi, Christopher Sebuyungo) for access to fossil material in its care, and the Uganda National Council for Science and Technology for authorization to carry out research in the country. Pierre Mein measured the specimen from Moroto and made preliminary identifications. Hugo Salais (Metazoa Studio) for the 3D reconstruction, Agustín Ruella for a previous version of the 3D reconstruction, Marcela Tomeo for the realisation of Figs 1 and 3, and Juana Yañez for the reconstruction of the palaeoenvironment. Francisco Javier Ruiz-Sánchez of University of València provided the use of the electron microscopy. Maria Dolores Marin-Monfort for the taphonomical comments. We should thank Frank Sénégas for making the casts (Sorbonne University). The fossils were collected by the Uganda Palaeontology Expedition led by B. Senut and funded by the Ministry of Foreign Affairs, Commission des Fouilles. We thank the villagers of Rupa for participating in the screening of the sediments which yielded the holotype of Morotodon aenigmaticus. The support of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) toward this research for V. D. Crespo is hereby acknowledged. V.D.C. is the beneficiary of a grant (ZA21-044) for the requalification Publisher Copyright: Copyright Vicente D.Morotodon aenigmaticus gen. et sp. nov. (Mammalia, Metatheria, ?Herpetotheriidae) from the early or early-middle Miocene of equatorial Africa (Moroto II locality, Moroto District, northeastern Uganda) is characterized by a short anterior cingulum, a buccal shelf, a well-developed hypoconulid in a central position, and a trigonid and talonid with similar mesio-distal lengths. Its small size and morphology suggest mostly insectivorous-faunivorous feeding habits. The faunal association of Moroto II, as well as previous palaeoenvironmental analyses, suggest that Morotodon lived in open woodland and bushland areas surrounded by grasses. Morotodon aenigmaticus shows several features reminiscent of early herpetotheriids, such as Golerdelphys stocki (late Paleocene of North America), and Amphiperatherium ambiguum (Eocene of Europe); this suggests an origin for its lineage previous to the Oligocene. In summary, its affinities lie with Northern Hemisphere herpetotheriids, and, most probably, with European ones.publishersversionpublishe

How do licensing regimes limit worker interests? Evidence from informal employment in Britain

Informalized workplaces are a growing presence in the UK, for example, hand car washes frequently house informalized low-wage, precarious workers who are paid less than the minimum wage and who experience other forms of labour market exploitation. These ‘new’ forms of work and the related informalization of work appear to challenge the embedded interplay between formal institutions and agency. Our contribution to new knowledge advances three areas of discussion. Firstly, what enables informalized workplaces to remain apparently unregulated? Secondly, in contrast to other locations why is there is no collective hybrid form of representation and resistance at car washes in the UK? Thirdly, how do licensing schemes for car washes have the potential to marginalize worker interests

An improved method for surface immobilisation of RNA: application to small Non-Coding RNA - mRNA pairing

Characterisation of RNA and its intermolecular interactions is increasing in importance as the inventory of known RNA functions continues to expand. RNA-RNA interactions are central to post-transcriptional gene regulation mechanisms in bacteria, and the interactions of bacterial small non-coding RNAs (sRNAs) with their mRNA targets are the subject of much current research. The technology of surface plasmon resonance (SPR) is an attractive approach to studying these interactions since it is highly sensitive, and allows interaction measurements to be recorded in real-time. Whilst a number of approaches exist to label RNAs for surface-immobilisation, the method documented here is simple, quick, efficient, and utilises the high-affinity streptavidin-biotin interaction. Specifically, we ligate a biotinylated nucleotide to the 3' end of RNA using T4 RNA ligase. Although this is a previously recognised approach, we have optimised the method by our discovery that the incorporation of four or more adenine nucleotides at the 3' end of the RNA (a poly-A-tail) is required in order to achieve high ligation efficiencies. We use this method within the context of investigating small non-coding RNA (sRNA)-mRNA interactions through the application of surface technologies, including quantitative SPR assays. We first focus on validating the method using the recently characterised Escherichia coli sRNA-mRNA pair, MicA-ompA, specifically demonstrating that the addition of the poly-A-tail to either RNA does not affect its subsequent binding interactions with partner molecules. We then apply this method to investigate the novel interactions of a Vibrio cholerae Qrr sRNA with partner mRNAs, hapR and vca0939; RNA-RNA pairings that are important in mediating pathogenic virulence. The calculated binding parameters allow insights to be drawn regarding sRNA-mRNA interaction mechanisms

Laser Ablation System for Solid Sample Analysis by Inductively Coupled Plasma Atomic Emission Spectrometry

A laser ablation sample introduction system, based on a Nd : YAG laser with an X-Y-Zdirectional sampling head, has been designed and constructed for use with inductively coupled plasma optical emission spectrometry. A study has been made of a number of parameters which affect the performance of the system to establish the optimum operating conditions. South African Reference Material (SARM) rock samples have been analysed using the system, and the results obtained have been compared with the certificate values. The importance of using closely matrix-matched samples and standards is demonstrated. Precision studies on SARM 5 (pyroxenite) show that both intra- and inter-sample precisions are typically 10% (relative standard deviation )

Structure of the regulatory hyaluronan binding domain in the inflammatory leukocyte homing receptor CD44

Adhesive interactions involving CD44, the cell surface receptor for hyaluronan, underlie fundamental processes such as inflammatory leukocyte homing and tumor metastasis. Regulation of such events is critical and appears to be effected by changes in CD44 N-glycosylation that switch the receptor "on" or "off" under appropriate circumstances. How altered glycosylation influences binding of hyaluronan to the lectin-like Link module in CD44 is unclear, although evidence suggests additional flanking sequences peculiar to CD44 may be involved. Here we show using X-ray crystallography and NMR spectroscopy that these sequences form a lobular extension to the Link module, creating an enlarged HA binding domain and a formerly unidentified protein fold. Moreover, the disposition of key N-glycosylation sites reveals how specific sugar chains could alter both the affinity and avidity of CD44 HA binding. Our results provide the necessary structural framework for understanding the diverse functions of CD44 and developing novel therapeutic strategies