Efficiency and herding analysis in gold-backed cryptocurrencies.

This study analyses and compares the behavior of the gold-backed, conventional cryptocurrency, and gold markets capable of detecting the existence of herding and deducing the efficiency degree. In addition, this empirical work tried to examine the COVID-19 pandemic's influence on both cryptocurrency performances. This work developed a new method that discloses herding biases using persistence and efficiency metrics. Besides, this paper investigated the nonlinear dynamic properties of the gold-backed, conventional cryptocurrencies and Gold by estimating the Multifractal Detrended Fluctuation Analysis (MFDFA). It also assessed the inefficiency of these markets through an efficiency index (IEI) and tested the effect of COVID-19 on their dynamics. The findings of this investigation indicate that the gold-backed cryptocurrency (X8X) is the most efficient market in the long-term trading market. However, the conventional cryptocurrency market (Bitcoin) is the most efficient on the short trade horizon. Besides, gold-backed cryptocurrency markets present a smaller level of herding behavior than conventional cryptocurrencies on tall scales. Nevertheless, we noted the positive and negative effects of the pandemic on each cryptocurrency market dynamics. To the best of the authors' knowledge, this study is the first investigation that uses multifractal analysis to quantify the impact of the COVID-19 spread on gold-backed cryptocurrencies and detects the presence of herding behavior.

[Management of urogenital prolapse in the maternity service of the Tunis military hospital. 82 cases]. / Prise en charge des prolapsus urogenitaux à la maternité de l'hôpital militaire de Tunis. A propos de 82 cas.

This survey has for goal to specify the epidemiological and of the prolapse of our patient, as well as our therapeutic attitude. It is about a retrospective survey that concerned 82 cases of prolapse, structural on a period of 5 years. The average of age of our patient is of 59 years. 73.17% of women are multiparous. 78% of women gave birth less once at home. The main motive of consultation is the vaginal ball sensation, in agreement with the total character of the prolapse that is the third degree in 46.34% of cases. The urinary incontinence is associated to the prolapse in 50% of cases. We achieved a vaginal surgery in 82.93 of cases. The hysterectomy has been achieved at 86.76% of operated then by vaginal surgery whereas for operated them by abdominal surgery, the uterus is preserved in the half of cases.