Evidences of Complexity of Magnitude Distribution, Obtained from a Non-Parametric Testing Procedure

Evidences of Complexity of Magnitude Distribution, Obtained from a Non-Parametric Testing Procedur

Ischémie mésentérique étendue associée à la prise excessive de naratriptan et de jus de pamplemousse

We reported the case of a 61-year-old woman, who has been hospitalized in ICU because of an extensive mesenteric ischaemia, involving the small bowel, secondary to a naratriptan overuse. This mesenteric ischaemia was complicated by multiple organ failure and was responsible for extensive small bowel resection and left colectomy. A concomitant abundant absorption of grapefruit juice, a well-known P450 inhibitor, may have enhanced this naratriptan toxicity. This case underscore that an abdominal pain occurring in the context of headache treatment may be related to a mesenteric ischaemia

Supplémentation en fer : indications, limites et modalités

During the past 10 years, the knowledge of iron metabolism has been revolutionized by the discovery of the main regulatory hormone of body iron: hepcidin. Meanwhile, new formulations of intravenous iron have been developed and are already or readily available. In this article, we review the recent pathophysiological mechanisms underlying anemia of chronic disease or due to iron deficiency. We describe the various treatment modalities of iron deficiency anemia using oral or intravenous route and the emerging indications of treatment with iron. Finally, we discuss the situations in which iron supplementation may be harmful

Non-stationarity and internal correlations of the occurrence process of mining-induced seismic events

A point process, e.g., the seismic process, is potentially predictable when it is non-stationary, internally correlated or both. In this paper, an analysis of the occurrence process of mining-induced seismic events from Rudna copper mine in Poland is presented. Stationarity and internal correlation are investigated in complete seismic time series and segmentally in subseries demonstrating relatively stable seismicity rates. It is shown that the complete seismic series are non-stationary; however, most of their shorter subseries become stationary. In the stationary subseries, the distribution of interevent time is closer to the exponential distribution, which is characteristic for the Poisson process. However, in most of these subseries, the differences between the interevent time and Poisson distributions are still significant, revealing correlations among seismic events

Impact de la carence martiale sur la fatigue en anesthésie-réanimation, de l’étude animale à la clinique humaine

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Iron deficiency without anemia is responsible for decreased left ventricular function and reduced mitochondrial complex I activity in a mouse model

BACKGROUND: Iron deficiency (ID), with or without anemia, is frequent in heart failure patients, and iron supplementation improves patient condition. However, the link between ID (independently of anemia) and cardiac function is poorly understood, but could be explained by an impaired mitochondrial metabolism. Our aim was to explore this hypothesis in a mouse model. METHODS AND RESULTS: We developed a mouse model of ID without anemia, using a blood withdrawal followed by 3-weeks low iron diet. ID was confirmed by low spleen, liver and heart iron contents and the repression of HAMP gene coding for hepcidin. ID was corrected by a single ferric carboxymaltose (FCM) injection (ID + FCM mice). Hemoglobin levels were similar in ID, ID + FCM and control mice. ID mice had impaired physical performances and left ventricular function (echocardiography). Mitochondrial complex I activity of cardiomyocytes was significantly decreased in ID mice, but not complexes II, III and IV activities. ID + FCM mice had improved physical performance, cardiac function and complex I activity compared to ID mice. Using BN-PAGE, we did not observe complex I disassembly, but a reduced quantity of the whole enzyme complex I in ID mice, that was restored in ID + FCM mice. CONCLUSIONS: ID, independently of anemia, is responsible for a decreased left ventricular function, through a reduction in mitochondrial complex I activity, probably secondary to a decrease in complex I quantity. These abnormalities are reversed after iron treatment, and may explain, at least in part, the benefit of iron supplementation in heart failure patients with ID

Влияние начального смещения обмоток на показатели электромеханического индукционного ускорителя цилиндрической конфигурации

Purpose. The purpose of the article is to determine the influence of the initial displacement of the windings on the indicators of an electromechanical induction accelerator of a cylindrical configuration with pulsed excitation from a capacitive energy storage and with short-term excitation from an alternating voltage source. Methodology. To take into account the interrelated electrical, magnetic, mechanical and thermal processes, as well as a number of nonlinear dependencies, we use the lumped parameters of the windings, and the solutions of the equations describing these processes are presented in a recurrent form. The mathematical model of the accelerator takes into account the variable magnetic coupling between the windings during the excitation of the inductor winding. When calculating the parameters and characteristics of the accelerator, a cyclic algorithm is used. Results. At a frequency of an alternating voltage source of 50 Hz, the current amplitude in the armature winding is less than in the inductor winding. With an increase in the source frequency to 250 Hz, the phase shift between the winding currents decreases. The current in the inductor winding decreases, and in the armature winding it increases. The accelerating components of the force increase, and the braking ones decrease. With an increase in the source frequency to 500 Hz, the current density in the armature winding exceeds that in the inductor winding. In this case, the phase shift between the windings is further reduced. Originality. When a cylindrical accelerator is excited, the largest amplitude of the current density in the inductor winding occurs at the maximum initial displacement of the windings, but the amplitude of the current density in the armature winding is the smallest. The largest value of the current density in the armature winding occurs in the absence of an initial displacement. When excited from a capacitive energy storage, the electrodynamic force between the windings has an initial accelerating and subsequent braking components. As a result, the speed of the armature initially increases to a maximum value, but decreases towards the end of the electromagnetic process. When a cylindrical accelerator is excited from an alternating voltage source, a phase shift occurs between the currents in the windings, which leads to the appearance of alternating accelerating and decelerating components of electrodynamic forces. The accelerating components of the force prevail over the braking components, which ensures the movement of the armature. Practical value. At a frequency of an alternating voltage source of 50 Hz, the highest speed at the output of the accelerator vzf=0.5 m/s is realized at an initial displacement of the windings z0=6.2 mm, at a frequency of 250 Hz, the highest speed vzf=2.4 m/s is realized at z0=3.1 mm, and at a frequency of 500 Hz the highest speed vzf=2.29 m/s is realized at z0=2.3 mm.В електромеханічному індукційному прискорювачі циліндричної конфігурації найбільша амплітуда струму в обмотці індуктора виникає при максимальному початковому зсуві, але амплітуда струму в обмотці якоря при цьому найменша. Найбільша величина струму в обмотці якоря виникає при відсутності початкового зсуву. При збудженні від ємнісного накопичувача енергії електродинамічна сила між обмотками має початкову прискорювальну і подальшу гальмівну складові. Внаслідок цього швидкість якоря спочатку зростає до максимально величини, але потім зменшується до моменту закінчення електромагнітного процесу. При збудженні прискорювача від джерела змінної напруги (ДЗН) між струмами в обмотках виникає фазовий зсув, що призводить до почергової зміни прискорювальних і гальмівних складових електродинамічної сили. Прискорювальні складові сили переважають над гальмівними складовими, що забезпечує переміщення якоря. При частоті ДЗН 50 Гц амплітуда струму в обмотці якоря менше, ніж в обмотці індуктора. Зі збільшенням частоти ДЗН фазовий зсув між струмами обмоток зменшується, струм в обмотці індуктора зменшується, а в обмотці якоря збільшується. Прискорювальні складові сили збільшуються, а гальмівні – зменшуються. При підвищенні частоти ДЗН до 500 Гц щільність струму в обмотці якоря перевищує аналогічну величину в обмотці індуктора