Two-colour generation in a chirped seeded Free-Electron Laser

We present the experimental demonstration of a method for generating two spectrally and temporally separated pulses by an externally seeded, single-pass free-electron laser operating in the extreme-ultraviolet spectral range. Our results, collected on the FERMI@Elettra facility and confirmed by numerical simulations, demonstrate the possibility of controlling both the spectral and temporal features of the generated pulses. A free-electron laser operated in this mode becomes a suitable light source for jitter-free, two-colour pump-probe experiments

Observation and Control of Laser-Enabled Auger Decay

Single photon laser enabled Auger decay (spLEAD) has been redicted theoretically [Phys. Rev. Lett. 111, 083004 (2013)] and here we report its first experimental observation in neon. Using coherent, bichromatic free-electron laser pulses, we have detected the process and coherently controlled the angular distribution of the emitted electrons by varying the phase difference between the two laser fields. Since spLEAD is highly sensitive to electron correlation, this is a promising method for probing both correlation and ultrafast hole migration in more complex systems.Comment: 5 pages, 3 figure

Transversality Conditions for Infinite Horizon Variational Problems on Time Scales

We consider problems of the calculus of variations on unbounded time scales. We prove the validity of the Euler-Lagrange equation on time scales for infinite horizon problems, and a new transversality condition.Comment: Submitted 6-October-2009; Accepted 19-March-2010 in revised form; for publication in "Optimization Letters"

Effects of systemic glucocorticosteroids on peripheral neutrophil functions in asthmatic subjects: an ex vivo study

In 21 asthmatic subjects, several functions of isolated peripheral neutrophils (chemokinesis and chemotaxis toward 10% E. coli; superoxide anion generation after PMA; leukotriene B4 (LTB4) release from whole blood and isolated neutrophtls, before and after different stimuli) were evaluated during an acute exacerbation of asthma, and after 14 – 54 days of treatment with systemic glucocorticosteroids (GCS). During acute exacerbation, superoxide anion generation was higher in asthmatics than in eleven normal subjects (39.2 ± 14.1 vs. 25.2 ± 7.3 nmol, p < 0.05); there was a significant correlation between FEV1 (% of predicted) and neutrophil chemotaxis (r = −0.52, p = 0.04). After treatment, there was no significant change in all neutrophil functions, except for a decrease in neutrophil chemotaxis in subjects who showed an FEV1 increase > 20% after GCS treatment (from 131 ± 18 to 117 ± 21 μm, p = 0.005). Chemokinesis sicantly decreased in all subjects, and the changes significantly correlated with an arbitrary score of the total administered dose of GCS (r = 0.57, p < 0.05). These data suggest that neutrophil activation plays a minor role in asthma, and that treatment with GCS is not able to modify most functions of peripheral neutrophils in asthmatic subjects; chemotaxis seems to be related only to the severity of the asthma and it could reflect the improvement of the disease

Association of pre-operative interleukin-6 levels with Interagency Registry for Mechanically Assisted Circulatory Support profiles and intensive care unit stay in left ventricular assist device patients

BACKGROUND: Inflammatory mechanisms are associated with worse prognosis in end-stage heart failure (ESHF) patients who require left ventricular assist device (LVAD) support. Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profiles describe patient condition at pre-implant and outcome. This study assessed the relationship among inflammation patterns and INTERMACS profiles in LVAD recipients. METHOD: Thirty ESHF patients undergoing LVAD implantation as bridge to transplant were enrolled. Blood and urine samples were collected pre-operatively and serially up to 2 weeks post-operatively for assessment of inflammatory markers (plasma levels of interleukin [IL]-6, IL-8, IL-10, and osteopontin, a cardiac inflammatory-remodeling marker; and the urine neopterin/creatinine ratio, a monocyte activation marker). Multiorgan function was evaluated by the total sequential organ failure assessment (tSOFA) score. Outcomes of interest were early survival, post-LVAD tSOFA score, and intensive care unit (ICU) length of stay. RESULTS: Fifteen patients had INTERMACS profiles 1 or 2 (Group A), and 15 had profiles 3 or 4 (Group B). At pre-implant, only IL-6 levels and the IL-6/IL-10 ratio were higher in Group A vs B. After LVAD implantation, neopterin/creatinine ratio and IL-8 levels increased more in Group A vs B. Osteopontin levels increased significantly only in Group B. The tSOFA score at 2 weeks post-LVAD and ICU duration were related with pre-implant IL-6 levels. CONCLUSIONS: The INTERMACS profiles reflect the severity of the pre-operative inflammatory activation and the post-implant inflammatory response, affecting post-operative tSOFA score and ICU stay. Therefore, inflammation may contribute to poor outcome in patients with severe INTERMACS profile

Prevention of incisional hernia post emergency laparotomy: A time to change? A case series.

Introduction: Complicated acute diverticulitis (CAD) is a surgical challenge in which a mini-invasive approach may be offered. Laparoscopic peritoneal lavage (LPL) was introduced as an alternative to sigmoid resection. However, the role of LPL is still under debate. Aim of this study was to evaluate which surgical strategy between LPL and Laparoscopic Sigmoidectomy (LS) could give better outcomes in CAD. Materials and methods: This prospective, observational, multicenter study lasted from 2015 until to 2018. Inclusion criteria: left colonic or sigmoid CAD (modified Hinchey’’s classification: grade II not responder to conservative treatment and grade III). Exclusion criteria: septic shock, immunodepression, previous multiple surgical operations, modified Hinchey’’s grade I and IV,\15 and[85 years. Comparisons were made between LPL and LS groups. Results: 66 patients were enrolled: 28 (42%) had LPL and 38 (58%) LS. Following sigmoidectomy, 24 pts (63%) had a primary anastomosis and 14 pts (37%) an end-colostomy (Hartmann’’s procedure). There were no significant differences regarding age, male gender rate and mean BMI (p = 0.314, p = 0.07, p = 0.129, respectively). ASA score [2 was significantly higher in LPL (p = 0.05). The number of previous episodes of diverticulitis and the mean C-Reactive Protein dosage were similar (p = 0.756 and 0.846). Mannheim Peritonitis Index was significantly higher in LPL (0.004). No differences were found regarding to the distribution of Hinchey’’s grades II and III (p = 0.727). 1 (4%) patient in LPL and 5 pts (13%) in LS needed a conversion to open surgery (p = 0.181). Overall, the morbidity rates were 33% in LPL and 18% in LS (p = 0.169). Organ space infection (30% vs 3%, p = 0.002) and the re-operation rates (18.5% vs 0; p = 0.006) resulted significantly higher in the LPL group. Mortality was nihil. Mean post-op length of stay was 11.4 days in LPL and 8.23 days in LS (p = 0.088). Diverticular recurrence was significantly increased in LPL (p = 0.003). Conclusions: Compared to LS, LPL is associated with increased ongoing sepsis, emergency re-intervention and recurrence of acute diverticulitis. The role of LPL for patients with CAD remains questionabl