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Background: Pheochromocytoma (PHEO) in pregnancy is a life-threatening condition. Its management is challenging with regards to the timing and type of surgery.Methods: A retrospective review of the management of ten patients diagnosed with pheochromocytoma during pregnancy was performed. Data were collected on the initial diagnostic workup, symptoms, treatment, and follow-up.Results: PHEO was diagnosed in ten patients who were between the 10th and the 29th weeks of pregnancy. Six patients had none to mild symptoms, while four had complications of paroxysmal hypertension. Imaging investigations consisted of MRI, CT scan and ultrasounds. All had urinary metanephrines, measured as part of their workup. Three patients had MEN 2A, one VHL syndrome, one suspected SDH mutation. All patients were treated either with α/β blockers or calcium channel blockers to stabilize their clinical conditions. Seven patients underwent a laparoscopic adrenalectomy before delivery. Three out of these seven patients had a bilateral PHEO and underwent a unilateral adrenalectomy of the larger tumor during pregnancy, followed by a planned cesarean section and a subsequent contralateral adrenalectomy within a few months after delivery. Three patients had emergency surgery for maternal or fetal complications, with C-section followed by concomitant or delayed adrenalectomy. All newborns from the group of planned surgery were healthy, while two out three newborns within the emergency surgery group died shortly after delivery secondary to cardiac and pulmonary complications.Conclusions: PHEO in pregnancy is a rare condition. Maternal and fetal prognosis improved over the last decades, but still lethal consequences may be present if misdiagnosed or mistreated. A thorough multidisciplinary team approach should be tailored on an individual basis to better manage the pathology. Unilateral adrenalectomy in a pregnant patient with bilateral PHEO may be an option to avoid the risk of adrenal insufficiency after bilateral adrenalectomy. [ABSTRACT FROM AUTHOR]

The paper presents a mathematical model of the non-localized fatigue damage accumulation process in rubberlike materials. A relation for the determination of the constants of the corresponding equation with allowance for known fatigue curve characteristics, in particular for their random spread, is proposed. Computational relationships for the determination of the probabilistic characteristics of damage have been derived. Experimental data for the determination of realization of the fatigue accumulation process in rubber specimens, which are in good agreement with theoretical results, are considered. [ABSTRACT FROM AUTHOR]

The influence of an electric discharge in a supersonic gas flow modeled by a heat source with a specified intensity and configuration on the development of a turbulent boundary layer ahead of a flat step is numerically studied. If the discharge power is sufficiently large, it is demonstrated that heat transfer to the wall does not affect the position of separation, which arises due to a non-zero shear stress on the body surface and is caused by the development of a reverse flow in the core of the boundary layer. [ABSTRACT FROM AUTHOR]

A decelerated flow in a supersonic boundary layer containing a heat source modeling an electric discharge is studied numerically. Calculations are performed for a wide range of the source power. The possibility of controlling the boundary layer separation is demonstrated. The boundary layer separation on cooled walls is found to occur substantially later than on thermally insulated walls. [ABSTRACT FROM AUTHOR]

The effect of the thermal action on a turbulent supersonic boundary–layer flow is studied numerically. It is shown that the friction force on an isothermal surface decreases significantly. The effectiveness of using a thermal source for decreasing friction is evaluated. [ABSTRACT FROM AUTHOR]

This Letter is devoted to numerical investigation of the effect of the electric discharge on the separation of a turbulent boundary layer before a flat step. Electric discharge is simulated by a heat liberation source of the specified intensity and configuration. It is shown that separation is possible at a sufficiently large discharge power and nonzero bias voltage across the wall. [ABSTRACT FROM AUTHOR]

The influence of electric discharge in a supersonic gas flow on the separation of a laminar boundary layer has been studied by numerical methods. The discharge is modeled by an energy supply source with preset intensity and configuration. It is established that the behavior of flows in the system with thermally insulated and isothermally cooled walls differs in a broad range of the heat source power. The possibility of controlling the boundary layer separation is demonstrated. [ABSTRACT FROM AUTHOR]

The original article was updated to correct the listing of A. Hamy's name; it is correct as displayed above. [ABSTRACT FROM AUTHOR]

A numerical analysis is made of a turbulent supersonic boundary layer with a heat source for a wide range of heat supplied to the gas. It is shown that the frictional resistance may be reduced appreciably and the efficiency of using a heat conductor to achieve such a reduction is estimated. [ABSTRACT FROM AUTHOR]