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The transition processes of the centrifugal pump in hydro accumulation power plant (HAPP) are studied in the article. The reliability of the pumping system is increased by the correct selection of the parameters of the transition process when regulating the operation of the pumping units. This prevents vibration damage and erosion. Based on the results obtained by calculating the hydraulic shock and the pressure loss in the system together, damage and failures in the pumping equipment and the network can be avoided. The results and graphs allow you to choose the right electric motor for the pump unit, taking into account the required pressure and water supply. Technical and economic efficiency is achieved by choosing a rated electric motor for the pump unit. Constructing graphic descriptions of the pump, determined the magnitude of the hydraulic effect in the grapho-analytical method.

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Petroleum drilling rigs are used for identifying geologic reservoirs and for creating wells for extraction. The mud pumps of drilling rigs are operated at high mud rates to make possible the drilling process. The durability of the mud pump valves to erosive wear, due to the action of abrasive drilling fluid containing solid particles, depends on their constructive form and on the mud flow velocity. This paper analyzes a few methods of increasing the wear resistance of mud pump valves.

Résumé Le nez et les fosses nasales assurent la ventilation, le conditionnement de l’air inspiré et l’olfaction. Ils peuvent être le siège de pathologies inflammatoires, infectieuses et tumorales ou d’anomalies architecturales préopératoires voire postopératoires, altérant ces fonctions, pour lesquelles l’examen clinique sera d’un rendement variable. Nous verrons tout d’abord, après un bref rappel physiologique, l’examen dit « de débrouillage » qui permettra au chirurgien non ORL de sélectionner les patients justifiant d’une exploration fonctionnelle préopératoire plus poussée. Nous présenterons ensuite les explorations complémentaires existantes : consultation ORL et endoscopie des fosses nasales, imagerie, technique de mesure du flux aérien nasal. À l’issue de ce bilan complémentaire, le praticien doit être en mesure : de savoir s’il existe ou non une obstruction nasale préopératoire et de la quantifier et de la rattacher à une cause, de dépister les contre-indications à la rhinoplastie mais aussi de connaître les structures anatomiques pouvant être à l’origine de troubles ventilatoires postopératoire, de prévoir d’emblée un geste adapté, qu’il soit esthétique pur ou esthético-fonctionnel. Au total, il existera 3 groupes de patients : ceux qui ne présentent aucune contre-indication au geste de rhinoplastie, ceux qui présentent une indication de geste esthético-fonctionnel, ceux qui présentent une contre-indication à la rhinoplastie. Summary Nose and nasal cavity provide ventilation, inspired air conditioning and olfaction. They may be the seat of inflammatory, infectious and malignant disease, or preoperative or postoperative architectural abnormalities, altering these functions, for which clinical examination will be a variable return. First of all, we’ll see, after a brief physiological reminder, descrambling examination which allows non-ENT surgeon to select patients justifying a further preoperative functional exploration. In total, there will be three groups of patients: those who have no cons-indication to rhinoplasty, those with an indication of aesthetic and functional rhinoseptoplasty, those with cons-indication for rhinoplasty. [ABSTRACT FROM AUTHOR]

Abstract: Ureteric valves are a rare cause of ureteric obstruction. Fifty cases have been described in the literature. We report two new cases. The first is of a 12-year-old child with left multiple ureteric valves associated to bilateral vesico-ureteric reflux. The patient was treated by uretero-ileoplasty with unfavourable evolution to renal failure. The second case is that of a proximal ureteric valve discovered in a 30-year-old woman who had postpartum acute pyelonephritis. Treatment consisted in ureteric resection–anastomosis with favourable outcome. Based on a review of the literature, we discuss epidemiologic, etiologic, diagnostic and therapeutic aspects of this malformation. [Copyright &y& Elsevier]

Introduction: Percutaneous aortic valve replacement has been performed in daily practice for less than 10 years. This technique was until recently reserved for patients with very high surgical risk. There is little data in the literature documenting the impact of this percutaneous technique on the patient population continuing to benefit from a surgical replacement of the aortic valve. We studied the characteristics of these patients immediately before and after the introduction of the percutaneous technique in the CHU Brugmann., Materials and Methods: Two separate cohorts of patients were retrospectively studied: one before the percutaneous era between 2005 and 2010 and the other after introduction of the percutaneous technique in our daily practice between 2010 and 2015. Demographic, intraoperative, mortality and postoperative morbidity indices were compared., Results: The number of surgical replacements of the aortic valve was 194 before and 132 after introduction of the percutaneous technique. The demographic, operative characteristics and postoperative morbidity and mortality of the patients remained the same between the two cohorts. Only the incidence of pulmonary arterial hypertension (12.1 vs 25 %, p = 0.015) and recent myocardial infarction (0 vs 3 %, p = 0.003) were higher in the second cohort., Conclusion: Replacement of the aortic valve percutaneously did not significantly change the demographic characteristics and postoperative morbidity and mortality of patients candidate for surgical replacement of the aortic valve. Nevertheless, after its introduction, the number of surgical replacements dropped considerably in our center.

Nose and nasal cavity provide ventilation, inspired air conditioning and olfaction. They may be the seat of inflammatory, infectious and malignant disease, or preoperative or postoperative architectural abnormalities, altering these functions, for which clinical examination will be a variable return. First of all, we'll see, after a brief physiological reminder, descrambling examination which allows non-ENT surgeon to select patients justifying a further preoperative functional exploration. In total, there will be three groups of patients: those who have no cons-indication to rhinoplasty, those with an indication of aesthetic and functional rhinoseptoplasty, those with cons-indication for rhinoplasty., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

Summary: Increasing life expectancy coupled to an increasing incidence of cardiovascular disease with age is leading to an ever increasing number of elderly referred for aortic valve replacement. Patients. —: Hospital mortality has been analysed and updated according to a group of 442 patients aged ⩾80 years who underwent an aortic valve replacement between January 2000 and December 2004 either isolated (n = 344) or associated with coronary revascularisation (n = 86), mitral valvuloplasty (n = 5) or aortic surgery (n = 7). A group of 621 octogenarians operated before December 2000 was analysed in order to determine long term results. Results. —: Operative mortality is 7.5% (n = 33). Independent predictive factors of mortality were : aortic insufficiency (30%, p < 0.004), NYHA class IV (20.5%, p < 0.001), left and right heart failure (11.5 % and 19.4%, p < 0.02), chronic renal insufficiency (18.5%, p < 0.04), emergency (37.5%, p < 0.001, OR = 4.7) left ventricular ejection fraction (21.1 %, p < 0.004, OR = 0.9) and redo surgery (35.3%, p < 0.001, OR = 6). Mortality was also increased in case of coronary revascularization (11.6%), mitral or tricuspid surgery (20%) and ascending aorta procedure (25%). Conclusion. —: Functionnal improvement and increasing long term survival obtained at the cost of a rather low operative mortality, justify aortic valve replacement in octogenarians. Surgical decision should be taken on an individual basis taking into account general status and mental heath. [Copyright &y& Elsevier]