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We have performed an extended palaeomagnetic study of the Oslo Graben volcanics, compared to the study of half a century ago by van Everdingen, using modern techniques and a four times larger amount of sites, plus additional rock magnetic experiments. We conclude that the average direction (D = 204.0, I = -37.9, k = 46.9, α95 = 2.0) and associated palaeomagnetic pole (λ = 48.3, φ = 155.5, K = 52.2, A95 = 1.9) of the Krokskogen and Vestfold volcanics together are statistically identical to those of the earlier study. This gives confidence in the fact that older palaeomagnetic studies can be reliable and robust, even though methods have improved. Our larger number of samples, and better age constraints, enable us to separate the data into two major intervals: the younger, on average, Krokskogen area and the older Vestfold area. The results show firstly that palaeolatitudes are slightly higher than predicted by the latest apparent polar wander path (APWP) for Eurasia by Torsvik et al. These data support an early Permian Pangaea A configuration and do not necessitate a Pangaea B configuration. The larger data set also allows us to assess the distribution of the characteristic remanent magnetization directions of the Oslo Graben in terms of geomagnetic field behaviour, which were acquired during a long period of dominantly single polarity the Permo-Carboniferous Reversed Superchron (PCRS). The distributions show a significantly lower virtual geomagnetic pole (VGP) scatter at the observed (low) latitudes than expected from a compilation from lavas of the last 5 Myr. The data do however show excellent agreement with the scatter observed both during the Cretaceous Normal Superchron and the PCRS. A comparison of the directional distributions in terms of elongation is less discriminating, since the large errors in all cases allow a fit to the predicted elongation/inclination behaviour of the TK03.GAD model. [ABSTRACT FROM AUTHOR]

A notion of Gaussian hemigroup is introduced and its relationship with the Gauss condition is studied. Moreover, a Lévy-type martingale characterization is proved for processes with independent (not necessarily stationary) increments satisfying the Gauss condition in a compact Lie group. The characterization is given in terms of a faithful finite dimensional representation of the group and its tensor square. For the proofs noncommutative Fourier theory is applied for the convolution hemigroups associated with the increment processes. [ABSTRACT FROM AUTHOR]

In this paper we study certain maximal functions for a class of Chébli-Trimèche hypergroups. Versions of the standard maximal theorems for these maximal functions are established and some applications are given. [ABSTRACT FROM AUTHOR]

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SARS-Coronavirus-2 (COVID-19) infection is a pandemic with various clinical presentations including pericarditis which seems to be rare. The aim of this observational cohort study was to describe characteristics and management of the patients hospitalized for pericarditis secondary to COVID 19 in the Hospital of Haguenau, France. We retrospectively enrolled patients admitted for pericarditis secondary to COVID 19 affection, either confirmed by a typical chest CT scan, or a positive Covid 19 PCR. Data were collected by a careful review of their medical record. 7 patients (4 men, 3 women) were included, with a median age of 60 and a median body mass index of 27.8 kg/m2. One of them took angiotensin II receptor antagonists, and none angiotensin converting enzyme inhibitors. Chest pain and dyspnea were the most common initial symptoms. Pericarditis were diagnosed with a median delay of 21 days after the onset of symptoms. The biology showed an inflammatory syndrome (median CRP at 104 mg/L). The troponin peak value was increased in two cases. Chest computed tomography revealed a typical lung COVID-19 affection in 4 cases and a pericardial effusion in every cases. Left ventricle ejection fraction assessed by echocardiography was normal. Two cases evolved into cardiac tamponade, which needed pericardiocentesis. One of the two cases of tamponade had a negative COVID 19 nasopharyngeal PCR and no pulmonary sign of the affection on the chest CT, but the Covid-19 PCR on pericardial fluid was positive. One patient required oxygen supply. Treatment with Colchicine was systematically initiated. Non-steroidal anti-inflammatory drugs were not introduced considering the risk of respiratory worsening. The 1-month follow-up revealed no death and a decrease of the pericardial effusion. This study suggest a higher prevalence of COVID-19-associated pericarditis than initially presumed, with heterogeneous clinical presentations. [ABSTRACT FROM AUTHOR]