Mycoplasmas of the urogenital tract of sheep

The role of mycoplasmas, especially ureaplasmas, in the urogenital tract of sheep was investigated both by survey and by pathogenicity experiments in vitro and in vivo.The survey revealed that Ureaplasma are the most frequently isolated species from the ovine urogenital tract, and demonstrated an association between the occurrence of vulvovaginitis and the presence of ureaplasmas. M.capricolum and A.axanthum, two species not previously reported in the United Kingdom, were among the other seven species isolated.Differences in virulence of the strains of ureaplasma isolated from sheep were investigated using both in vitro and in vivo systems. The in vitro systems used were cell and organ cultures as well as embryonated hens' eggs, but although none of these gave successful results, a cytopathic effect observed in ovine uterus cell cultures did suggest that these organisms are potentially pathogenic. The various in vivo systems investigated included inoculation of several animal species by a variety of routes. The production of mastitis in lactating mice after intramammary inoculation confirmed the pathogenicity seen in cell cultures but possible variations in virulence between strains were not identified by this model. However, the strains varied in their ability to induce mastitis in the lactating bovine udder, suggesting that variations in virulence do occur but are revealed only by in vivo systems.Transmission experiments in sheep were carried out and demonstrated that inoculation of these organisms per vaginam resulted in vulvitis. They showed also the importance of venereal transmission in the spread of the organisms to previously unmated ewes, some of which developed vulvitis. Ureaplasmas could be consistently recovered from all animals which developed the disease. The vulvitis did not affect conception rates or the reproductive efficiency of the ewes.Two serological tests (metabolism-inhibition and indirect immunofluorescence) demonstrated that at least three groups of ovine ureaplasmas occur in the United Kingdom. All 106 strains examined in this study could be assigned to one of the three groups, using antisera prepared in specific pathogen-free lambs ,against a representative of each group

Les galipettes de l’Autre burlesque ou la mécanique corporelle du Double

La gestuelle des dégénérés Dans les années d’émergence du cinéma, l’une des principales constructions médicales pour conceptualiser le fonctionnement de la psyché consiste en une division entre les facultés supérieures – la raison, le jugement, la volonté –, et les facultés inférieures – les fonctions sensori-motrices, les automatismes comprenant les réflexes nerveux et l’instinct. Ce sont ces facultés inférieures qui composent « l’inconscient corporel ». Cette conception d’une divisi..

Variability and sources of the southeastern Atlantic circulation

The 1992–1993 Benguela Sources and Transport (BEST) time series provide a quantitative view of the Benguela Current transport and the eddy field crossing 30S, as well as an estimate of the relation between its barotropic and baroclinic components. This is done by a simultaneous analysis of the BEST data derived from inverted echo sounders, pressure sensors, current meter moorings, CTD, and ADCP stations. The analysis of the time series indicates that the annual mean baroclinic transport of the Benguela Current is 13 Sv with a total transport of 16 Sv. Through the combination of instruments the total baroclinic plus barotropic transport of the upper 2600 m was obtained without making any assumption about the level of no motion. Results from this calculation corroborated the assumption that 1000 m as a level of no motion could be used as a fairly good approximation. The stationary flow of the Benguela Current is mostly confined near the African Continent while a transient flow, composed by large eddies shed from the Agulhas retroflection, dominates the western portion of the Benguela Current. In the stationary part of the Benguela Current, both barotropic and baroclinic components are equally important while in the transient part, the barotropic is more substantial. Several rings were observed during the experiment that migrated toward the west. An initial speed of 12 km/day diminished to 6 to 7 km/day at the Walvis Ridge. The water mass source of the Benguela Current includes Indian and South Atlantic subtropical thermocline water; relatively saline, low oxygen tropical Atlantic water; and the cooler, fresher subantarctic water. Changes in thermocline salinity correlate with transport: in general when the northward transport is increasing the thermocline salinity also increases, without a decrease in oxygen. This indicates that the Benguela Current increases in strength by bringing in more subtropical thermocline water. As the Agulhas input is most effective in boosting the salinity of the upper thermocline (the South Atlantic Current water being deficit in salinity relative to the Indian Ocean source) we suggest that the spatial variations in transport are tied to Agulhas water influx, presumably associated with the eddy field

Lessons for conservation management: Monitoring temporal changes in genetic diversity of Cape mountain zebra (Equus zebra zebra)

The Cape mountain zebra (Equus zebra zebra) is a subspecies of mountain zebra endemic to South Africa. The Cape mountain zebra experienced near extinction in the early 1900's and their numbers have since recovered to more than 4,800 individuals. However, there are still threats to their long-term persistence. A previous study reported that Cape mountain zebra had low genetic diversity in three relict populations and that urgent conservation management actions were needed to mitigate the risk of further loss. As these suggestions went largely unheeded, we undertook the present study, fifteen years later to determine the impact of management on genetic diversity in three key populations. Our results show a substantial loss of heterozygosity across the Cape mountain zebra populations studied. The most severe losses occurred at De Hoop Nature Reserve where expected heterozygosity reduced by 22.85% from 0.385 to 0.297. This is alarming, as the De Hoop Nature Reserve was previously identified as the most genetically diverse population owing to its founders originating from two of the three remaining relict stocks. Furthermore, we observed a complete loss of multiple private alleles from all populations, and a related reduction in genetic structure across the subspecies. These losses could lead to inbreeding depression and reduce the evolutionary potential of the Cape mountain zebra. We recommend immediate implementation of evidence-based genetic management and monitoring to prevent further losses, which could jeopardise the long term survival of Cape mountain zebra, especially in the face of habitat and climate change and emerging diseases

The EMT-activator ZEB1 is unrelated to platinum drug resistance in ovarian cancer but is predictive of survival

The IGROVCDDP cisplatin-resistant ovarian cancer cell line is an unusual model, as it is also cross-resistant to paclitaxel. IGROVCDDP, therefore, models the resistance phenotype of serous ovarian cancer patients who have failed frontline platinum/taxane chemotherapy. IGROVCDDP has also undergone epithelial-mesenchymal transition (EMT). We aim to determine if alterations in EMT-related genes are related to or independent from the drug-resistance phenotypes. EMT gene and protein markers, invasion, motility and morphology were investigated in IGROVCDDP and its parent drug-sensitive cell line IGROV-1. ZEB1 was investigated by qPCR, Western blotting and siRNA knockdown. ZEB1 was also investigated in publicly available ovarian cancer gene-expression datasets. IGROVCDDP cells have decreased protein levels of epithelial marker E-cadherin (6.18-fold, p = 1.58e−04) and higher levels of mesenchymal markers vimentin (2.47-fold, p = 4.43e−03), N-cadherin (4.35-fold, p = 4.76e−03) and ZEB1 (3.43-fold, p = 0.04). IGROVCDDP have a spindle-like morphology consistent with EMT. Knockdown of ZEB1 in IGROVCDDP does not lead to cisplatin sensitivity but shows a reversal of EMT-gene signalling and an increase in cell circularity. High ZEB1 gene expression (HR = 1.31, n = 2051, p = 1.31e−05) is a marker of poor overall survival in high-grade serous ovarian-cancer patients. In contrast, ZEB1 is not predictive of overall survival in high-grade serous ovarian-cancer patients known to be treated with platinum chemotherapy. The increased expression of ZEB1 in IGROVCDDP appears to be independent of the drug-resistance phenotypes. ZEB1 has the potential to be used as biomarker of overall prognosis in ovarian-cancer patients but not of platinum/taxane chemoresistance

Shakeout in the Early Commercial Airframe Industry

The commercial airframe industry in the US experienced a shakeout from the early 1930s into the post‐Second World War period. Unlike shakeouts in automobiles, tyres, or televisions, the commercial airframe industry\u27s early life cycle was affected by external factors, particularly government demand. Using newly digitized data on all planes introduced in the commercial market between 1926 and 1965, we find that commercial airframe manufacturers with bomber contracts during the Second World War were more likely to have postwar market share than firms without such contracts, controlling for plane characteristics and other forms of government contracting. We attribute the effect of bomber contracts to advantages in R&D learning capacity acquired by firms with military airframe contracts. Despite low (or zero) initial presence in the commercial market, these learning capacity advantages allowed such firms to survive the early period of the shakeout, and later to thrive

Near-Earth initiation of a terrestrial substorm

Despite the characterization of the auroral substorm more than 40 years ago, controversy still surrounds the processes triggering substorm onset initiation. That stretching of the Earth's magnetotail following the addition of new nightside magnetic flux from dayside reconnection powers the substorm is well understood; the trigger for explosive energy release at substorm expansion phase onset is not. Using ground-based data sets with unprecedented combined spatial and temporal coverage, we report the discovery of new localized and contemporaneous magnetic wave and small azimuthal scale auroral signature of substorm onset. These local auroral arc undulations and magnetic field signatures rapidly evolve on second time scales for several minutes in advance of the release of the auroral surge. We also present evidence from a conjugate geosynchronous satellite of the concurrent magnetic onset in space as the onset of magnetic pulsations in the ionosphere, to within technique error. Throughout this time period, the more poleward arcs that correspond to the auroral oval which maps to the central plasma sheet remain undisturbed. There is good evidence that flows from the midtail crossing the plasma sheet can generate north-south auroral structures, yet no such auroral forms are seen in this event. Our observations present a severe challenge to the standard hypothesis that magnetic reconnection in stretched magnetotail fields triggers onset, indicating substorm expansion phase initiation occurs on field lines that are close to the Earth, as bounded by observations at geosynchronous orbit and in the conjugate ionosphere

Experimental motivation and empirical consistency in minimal no-collapse quantum mechanics

We analyze three important experimental domains (SQUIDs, molecular interferometry, and Bose-Einstein condensation) as well as quantum-biophysical studies of the neuronal apparatus to argue that (i) the universal validity of unitary dynamics and the superposition principle has been confirmed far into the mesoscopic and macroscopic realm in all experiments conducted thus far; (ii) all observed "restrictions" can be correctly and completely accounted for by taking into account environmental decoherence effects; (iii) no positive experimental evidence exists for physical state-vector collapse; (iv) the perception of single "outcomes" is likely to be explainable through decoherence effects in the neuronal apparatus. We also discuss recent progress in the understanding of the emergence of quantum probabilities and the objectification of observables. We conclude that it is not only viable, but moreover compelling to regard a minimal no-collapse quantum theory as a leading candidate for a physically motivated and empirically consistent interpretation of quantum mechanics.Comment: 24 pages, 11 figures, final published versio

The difference that tenure makes

This paper argues that housing tenures cannot be reduced to either production relations or consumption relations. Instead, they need to be understood as modes of housing distribution, and as having complex and dynamic relations with social classes. Building on a critique of both the productionist and the consumptionist literature, as well as of formalist accounts of the relations between tenure and class, the paper attempts to lay the foundations for a new theory of housing tenure. In order to do this, a new theory of class is articulated, which is then used to throw new light on the nature of class-tenure relations