Computational investigation of diesel nozzle internal flow during the complete injection event

[EN] Currently, diesel engines are calibrated using more and more complex multiple injection strategies. Under these conditions, the characteristics of the flow exiting the fuel injector are strongly affected by the transient interaction between the needle, the sac volume and the orifices, which are not yet clear. In the current paper, a methodology combining a 1D injector model and 3D-CFD simulations is proposed. First, the characteristics of the nozzle flow have been experimentally assessed in transient conditions by means of injection rate and momentum flux measurements. Later, the 3D-CFD modeling approach has been validated at steady-state fixed lift conditions. Finally, a previously developed 1D injector model has been used to extract the needle lift profiles and transient pressure boundary conditions used for the full-transient 3D-CFD simulations, using adaptive mesh refinement (AMR) strategies to be able to simulate the complete injection rate starting from 1 mu m lift.This work was partly sponsored by "Ministerio de Economia y Competitividad'', of the Spanish Government, in the frame of the Project "Estudio de la interaccion chorro-pared en condiciones realistas de motor'', Reference TRA2015-67679-c2-1-R. The authors would like also to thank the computer resources, technical expertise and assistance provided by Universidad de Valencia in the use of the supercomputer "Tirant''. 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Association between age at disease onset of anti-neutrophil cytoplasmic antibody-associated vasculitis and clinical presentation and short-term outcomes

Objectives: ANCA-associated vasculitis (AAV) can affect all age groups. We aimed to show that differences in disease presentation and 6 month outcome between younger- A nd older-onset patients are still incompletely understood. Methods: We included patients enrolled in the Diagnostic and Classification Criteria for Primary Systemic Vasculitis (DCVAS) study between October 2010 and January 2017 with a diagnosis of AAV. We divided the population according to age at diagnosis: <65 years or ≥65 years. We adjusted associations for the type of AAV and the type of ANCA (anti-MPO, anti-PR3 or negative). Results: A total of 1338 patients with AAV were included: 66% had disease onset at <65 years of age [female 50%; mean age 48.4 years (s.d. 12.6)] and 34% had disease onset at ≥65 years [female 54%; mean age 73.6 years (s.d. 6)]. ANCA (MPO) positivity was more frequent in the older group (48% vs 27%; P = 0.001). Younger patients had higher rates of musculoskeletal, cutaneous and ENT manifestations compared with older patients. Systemic, neurologic,cardiovascular involvement and worsening renal function were more frequent in the older-onset group. Damage accrual, measured with the Vasculitis Damage Index (VDI), was significantly higher in older patients, 12% of whom had a 6 month VDI ≥5, compared with 7% of younger patients (P = 0.01). Older age was an independent risk factor for early death within 6 months from diagnosis [hazard ratio 2.06 (95% CI 1.07, 3.97); P = 0.03]. Conclusion: Within 6 months of diagnosis of AAV, patients >65 years of age display a different pattern of organ involvement and an increased risk of significant damage and mortality compared with younger patients

Adhesions and Anti-Adhesion Systems Highlights.

The peritoneal and intrauterine cavities are lined by fragile membranes with a high-wound healing capacity, e.g. repairing the endometrium in its cyclical "injury and scar-free repair process" during menstruation. However, peritoneal and intrauterine fibrosis and adhesions can develop after surgical trauma through activation of molecular, immune and genetic mechanisms. During procedures with a high-risk of adhesions, the use of new peritoneal and intrauterine conditions in combination with anti-adhesion substances are promising measures to preserve peritoneal and endometrial function and avoid the most common complication of gynecological surgery. Highlights of adhesions and anti-adhesion prevention techniques in laparoscopic, laparotomic and hysteroscopic surgeries are discussed in this paper. Unfortunately, evidence is lacking to prove the superiority of one technique over its counterparts in terms of postoperative adhesions, such as instrumentation, type of energy, distending media, and intracavitary pressure. Additionally, there is limited evidence about the efficacy and outcomes of techniques and adjuvant measures used during adhesiolysis. The definition of a universal intrauterine adhesions classification scheme as well as a prognostic scoring system to identify women at high risk of postoperative adhesions are necessary for advising those who could benefit the most of the use of antiadhesion barriers.status: publishe