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Femtosecond laser sources with high repetition rate in the ultraviolet (UV) and vacuum UV (VUV) are fundamental tools enabling tabletop time-resolved and angle-resolved photoemission spectroscopy in solids. We describe a VUV source at 114 nm (10.8 eV) based on an industrial grade ytterbium-doped ultrafast laser, a nonlinear pulse width selection stage, and two cascaded frequency tripling stages, first in crystals, second in xenon. The role of ionization in gas-based perturbative third harmonic generation phase-matching is analyzed using a simple theory, numerical simulations, and experimental data. The source features high photon flux, high repetition rate, and adjustable time resolutions. Thereby, in combination with a state-of-the-art angle-resolved photoemission spectroscopy (ARPES) apparatus it enables the study of the electronic dynamics of the whole Brillouin zone in a large number of materials.

Dialkylcarbamoylchloride dressing is a fatty acid derivative that has been shown in vitro to bind a number of pathogenic microorganisms. The purpose of this prospective study was to evaluate the safety and the efficacy of this technology in the care of the exit site of central venous catheter in a paediatric and neonatal population., Methods: The study was conducted from September 2020 to December 2022 at the Infermi Hospital in Rimini. Central venous catheters were placed using the SIC bundle for insertion. Dialkylcarbamoylchloride dressing was placed below the subcutaneous anchoring at the time of CVC placement and at each dressing change. Data about the catheters and the exit site were recorded and then compared with an historical cohort., Results: 118 catheters were placed during the studied period. The dialkylcarbamoylchloride dressing was well-tolerated. No case of systemic or local infection was recorded. The comparison with the historical cohort showed a reduction in the rate of exit site infection ( p value 0.03)., Conclusion: Dialkylcarbamoylchloride dressing is well-tolerated in paediatric and neonatal population. It represents a promising tool as a strategy for infection prevention.

This study investigated the effectiveness of an original Lung UltraSound Targeted Recruitment (LUSTR) protocol to improve the success of lung recruitment maneuvers (LRMs), which are performed as a rescue approach in critically ill neonates. All the LUSTR maneuvers, performed on infants with an oxygen saturation/fraction of inspired oxygen (S/F) ratio below 200, were included in this case-control study (LUSTR-group). The LUSTR-group was matched by the initial S/F ratio and underlying respiratory disease with a control group of lung recruitments performed following the standard oxygenation-guided procedure (Ox-group). The primary outcome was the improvement of the S/F ratio (Delta S/F) throughout the LRM. Secondary outcomes included the rate of air leaks. Each group was comprised of fourteen LRMs. As compared to the standard approach, the LUSTR protocol was associated with a higher success of the procedure in terms of Delta S/F (110 ± 47.3 vs. 64.1 ± 54.6, p = 0.02). This result remained significant after adjusting for confounding variables through multiple linear regressions. The incidence of pneumothorax was lower, although not reaching statistical significance, in the LUSTR-group (0 vs. 14.3%, p = 0.15). The LUSTR protocol may be a more effective and safer option than the oxygenation-based procedure to guide open lung ventilation in neonates, potentially improving ventilation and reducing the impact of ventilator-induced lung injury.

Objective: The study aims to establish the role of late aEEG (scored by Burdjalov) in predicting brain maturation as well as abnormalities evaluated at term equivalent age (TEA) by brain MRI., Methods: 91 infants born before 30 wks gestation underwent an aEEG monitoring at 32 wks postconceptional age (PCA). aEEG, was correlated with TEA MRI, scored by Kidokoro., Results: A significant correlation between the aEEG score and the MRI scores was found. The same results were obtained for the aEEG continuity score; cyclicity and bandwidth scores were associated with grey matter and cerebellar MRI items. Moreover, a correlation between aEEG and cEEG recorded both at 32 and 40 wks PCA, was found., Conclusions: aEEG monitoring can be predictive of MRI findings at TEA, suggesting that it could be implemented as a useful tool to support ultrasound to help identify neonates who will benefit from early intervention services., (© 2021. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Brain injury at birth is an important cause of neurological and behavioral disorders. Hypoxic-ischemic encephalopathy (HIE) is a critical cerebral event occurring acutely or chronically at birth with high mortality and morbidity in newborns. Therapeutic strategies for the prevention of brain damage are still unknown, and the only medical intervention for newborns with moderate-to-severe HIE is therapeutic hypothermia (TH). Although the neurological outcome depends on the severity of the initial insult, emerging evidence suggests that infants with mild HIE who are not treated with TH have an increased risk for neurodevelopmental impairment; in the current clinical setting, there are no specific or validated biomarkers that can be used to both correlate the severity of the hypoxic insult at birth and monitor the trend in the insult over time. The aim of this work was to examine the presence of autophagic and mitophagic proteins in bodily fluids, to increase knowledge of what, early at birth, can inform therapeutic strategies in the first hours of life. This is a prospective multicentric study carried out from April 2019 to April 2020 in eight third-level neonatal intensive care units. All participants have been subjected to the plasma levels quantification of both Parkin (a protein involved in mitophagy) and ATG5 (involved in autophagy). These findings show that Parkin and ATG5 levels are related to hypoxic-ischemic insult and are reliable also at birth. These observations suggest a great potential diagnostic value for Parkin evaluation in the first 6 h of life., (© 2022. The Author(s).)

We report about a setup for carrier-envelope phase (CEP) control and stabilization in passive systems based on difference frequency generation (DFG). The principle of this approach relies on the amplitude to phase modulation transfer in the white-light generation process. A small modulation of the pump laser intensity is used to obtain a DFG output modulated in CEP. This technique is demonstrated in a CEP-stable system pumped by an Yb-doped fiber amplifier. It is first characterized by measuring CEP modulations produced by applying arbitrary waveforms. The CEP actuator is then used for slow drifts correction in a feedback loop. The results show the capability of this simple approach for OPA/OPCPA CEP-stabilized setups.

Objective: To evaluate short-term respiratory outcomes in late preterm infants (LPI) compared with those of term infants (TI)., Methods: A retrospective study conducted in a single third level Italian centre (2005-2009) to analyse the incidence and risk factors of composite respiratory morbidity (CRM), the need for adjunctive therapies (surfactant therapy, inhaled nitric oxide, pleural drainage), the highest level of respiratory support (mechanical ventilation - MV, nasal continuous positive airway pressure--N-CPAP, nasal oxygen) and the duration of pressure support (hours in N-CPAP and/or MV)., Results: During the study period 14,515 infants were delivered. There were 856 (5.9%) LPI and 12,948 (89.2%) TI. CRM affected 105 LPI (12.4%), and 121 TI (0.9%), with an overall rate of 1.6%. Eighty-four LPI (9.8%) and 73 TI (0.56%) received respiratory support, of which 13 LPI (1.5%) and 16 TI (0.12%) were ventilated. The adjusted OR for developing CRM significantly increased from 3.3 (95% CI 2.0-5.5) at 37 weeks to 40.8 (95% CI 19.7-84.9%) at 34 weeks. The adjusted OR for the need of MV significantly increased from 3.4 (95% CI 1.2-10) at 37 weeks to 34.4 (95% CI 6.7-180.6%) at 34 weeks. Median duration of pressure support was significantly higher at 37 weeks (66.6 h vs 40.5 h). Twin pregnancies were related to a higher risk of CRM (OR 4.3, 95% CI 2.6-7.3), but not independent of gestational age (GA). Cesarean section (CS) was associated with higher risk of CRM independently of GA, but the OR was lower in CS with labour (2.2, 95% CI 1.4-3.4 vs 3.0, 95% CI 2.1-4.2)., Conclusions: In this single third level care study late preterm births, pulmonary diseases and supportive respiratory interventions were lower than previously documented. LPI are at a higher risk of developing pulmonary disease than TI. Infants born from elective cesarean sections, late preterm twins in particular and 37 weekers too might benefit from preventive intervention.

Background: The aims of the present study were (i) to characterize the relationship between mean airway pressure (PAW) and reactance measured at 5 Hz (reactance of the respiratory system (X RS), forced oscillation technique) and (ii) to compare optimal PAW (P opt) defined by X RS, oxygenation, lung volume (VL), and tidal volume (VT) in preterm lambs receiving high-frequency oscillatory ventilation (HFOV)., Methods: Nine 132-d gestation lambs were commenced on HFOV at PAW of 14 cmH2O (P start). PAW was increased stepwise to a maximum pressure (P max) and subsequently sequentially decreased to the closing pressure (Pcl, oxygenation deteriorated) or a minimum of 6 cmH2O, using an oxygenation-based recruitment maneuver. X RS, regional V L (electrical impedance tomography), and V T were measured immediately after (t 0 min) and 2 min after (t 2 min) each PAW decrement. P opt defined by oxygenation, X RS, V L, and V T were determined., Results: The PAW-X RS and PAW-VT relationships were dome shaped with a maximum at Pcl+6 cmH2O, the same point as P opt defined by VL. Below Pcl+6 cmH2O, X RS became unstable between t 0 min and t 2 min and was associated with derecruitment in the dependent lung. P opt, as defined by oxygenation, was lower than the P opt defined by X RS, V L, or V T., Conclusion: X RS has the potential as a bedside tool for optimizing PAW during HFOV.

The synthesis of strontium ferrite SrFeO(3-δ) has been explored through wet-chemistry methods in order to optimize a quick, easy and reproducible method to obtain the perovskite in pure crystalline form with a high yield. Among the three investigated synthetic paths, (i) coprecipitation of hydroxides, (ii) coprecipitation of oxalates and (iii) polyol-assisted coprecipitation, only the second one was effective in obtaining the desired perovskite modification as a single phase. The products were analyzed by means of powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), to determine the crystalline structure and the chemical composition of the sample surface, respectively, and to optimise the synthetic process. Pure samples were further characterised by means of inductively coupled plasma (ICP-AES) analysis, nitrogen adsorption, elemental analysis, temperature programmed reduction (TPR) and Mössbauer spectroscopy.

The study of respiratory mechanics in infants requires a noninvasive accurate measurement of the lung volume changes (DeltaVL). Optoelectronic plethysmography (OEP) allows the assessment of DeltaVL through the measurement of the chest wall surface motion and it has been proved to be accurate in adults. The aim of this study was to apply OEP to newborns and to validate it by comparison to pneumotachography. Twenty term and preterm newborns (GA = 34 +/- 5 wk) in stable condition were studied during 1 to 2 min periods of quiet breathing in supine position. Airway opening flow was measured by applying a facemask connected to a pneumotachograph (PNT) and integrated to provide the DeltaVL. Chest wall volume changes were simultaneously measured by OEP. The tidal volume values measured by pneumotachography and by OEP were compared for each breath. A total of 771 breaths from all patients were considered. Bland-Altmann analysis showed a mean difference of -0.08 mL and a limit of agreement ranging from -2.98 to 2.83 mL. Linear regression analysis demonstrated good correlation between the two techniques (r = 0.95, q = 1.00 mL, m = 0.96). OEP provides accurate measurements of DeltaVL in newborns and may be useful to study respiratory mechanics and breathing patterns during spontaneous breathing and mechanical ventilation.

Evidence on the efficacy of standardised phytoterapic extracts for the prevention of recurrent respiratory tract infections (RRTIs) in children is reviewed. Echinacea extracts are widely used in European countries and in the United States as immune-stimulating agents. However, further prospective, appropriately powered clinical studies are required to confirm their benefits in reducing duration and severity of RRTIs.