Experimentally constrained 165,166Ho(n,γ)^{165,166}\text{Ho}(n,\gamma) rates and implications for the ss process

The $\gamma$-ray strength function and the nuclear level density of $^{167}$Ho have been extracted using the Oslo method from a $^{164}\text{Dy}(\alpha,p\gamma)^{167}$Ho experiment carried out at the Oslo Cyclotron Laboratory. The level density displays a shape that is compatible with %can be approximated with the constant temperature model in the quasicontinuum, while the strength function shows structures indicating the presence of both a scissors and a pygmy dipole resonance. Using our present results as well as data from a previous $^{163}\text{Dy}(\alpha,p\gamma)^{166}$Ho experiment, the $^{165}\text{Ho}(n,\gamma)$ and $^{166}\text{Ho}(n,\gamma)$ MACS uncertainties have been constrained. The possible influence of the low-lying, long-lived 6~keV isomer $^{166}$Ho in the $s$ process is investigated in the context of a 2~$M_\odot$, [Fe/H]=-0.5 AGB star. We show that the newly obtained $^{165}\text{Ho}(n,\gamma)$ MACS affects the final $^{165}$Ho abundance, while the $^{166}\text{Ho}(n,\gamma)$ MACS only impacts the enrichment of $^{166,167}$Er to a limited degree due to the relatively rapid $\beta$ decay of the thermalized $^{166}$Ho at typical $s$-process temperatures.Comment: 11 pages, submitted to Physical Reviews

Triaxiality in neutron-rich Ruthenium isotopes, New lifetimes measured in Ru-109,110,111

This thesis explores the asymmetrical deformation of Ruthenium isotopes, aiming to provide reliable experimental data useful for testing theoretical nuclear structure models. We have obtained reduced transition probabilities B(E2) for a number of transitions in Ru-109,110,111. A fit of the generalised triaxial rotor model indicates Ru-110 is well deformed, with a slightly oblate triaxial shape. The results are compared to various global nuclear structure models. First approximation reveals no evidence of shape changes between Ru-109 and Ru-111, more accurate results will be achieved through triaxial particle rotor calculations. The dataset at the heart of the analysis, obtained with AGATA and VAMOS++ at GANIL in 2017, features much higher statistics for a much larger number of nuclei than have previously been available. This has allowed us to get reliable lifetime measurements for the neutron odd Ru-109,111, and for both the ground- state band and one phonon γ-band in Ru-110. Additionally, it is expected to significantly reduce systematic errors when comparing results from different nuclei. We have developed and applied a new method for extracting lifetimes from the decay curves obtained in recoil distance Doppler shift measurements. By imposing constraints of physicality, it is expected to produce more reliable results than previous methods. A code for simultaneously fitting multiple gamma-spectra with shared parameters has also been developed

Commissioning of Miniball: a new digital data acquisition system

In this report, I present my work as part of the CERN Summer Student Pro- gramme. The project was part of the commissioning phase of the Miniball de- tector array at ISOLDE, as a new digital data acquisition was being installed. It consisted in doing offline analyses of real and simulated data to compare with the online output of the new system, in developing an automated calibration procedure for the detectors, and contributing where needed during the commissioning

Evolution over Time of Ventilatory Management and Outcome of Patients with Neurologic Disease∗

OBJECTIVES: To describe the changes in ventilator management over time in patients with neurologic disease at ICU admission and to estimate factors associated with 28-day hospital mortality. DESIGN: Secondary analysis of three prospective, observational, multicenter studies. SETTING: Cohort studies conducted in 2004, 2010, and 2016. PATIENTS: Adult patients who received mechanical ventilation for more than 12 hours. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the 20,929 patients enrolled, we included 4,152 (20%) mechanically ventilated patients due to different neurologic diseases. Hemorrhagic stroke and brain trauma were the most common pathologies associated with the need for mechanical ventilation. Although volume-cycled ventilation remained the preferred ventilation mode, there was a significant (p < 0.001) increment in the use of pressure support ventilation. The proportion of patients receiving a protective lung ventilation strategy was increased over time: 47% in 2004, 63% in 2010, and 65% in 2016 (p < 0.001), as well as the duration of protective ventilation strategies: 406 days per 1,000 mechanical ventilation days in 2004, 523 days per 1,000 mechanical ventilation days in 2010, and 585 days per 1,000 mechanical ventilation days in 2016 (p < 0.001). There were no differences in the length of stay in the ICU, mortality in the ICU, and mortality in hospital from 2004 to 2016. Independent risk factors for 28-day mortality were age greater than 75 years, Simplified Acute Physiology Score II greater than 50, the occurrence of organ dysfunction within first 48 hours after brain injury, and specific neurologic diseases such as hemorrhagic stroke, ischemic stroke, and brain trauma. CONCLUSIONS: More lung-protective ventilatory strategies have been implemented over years in neurologic patients with no effect on pulmonary complications or on survival. We found several prognostic factors on mortality such as advanced age, the severity of the disease, organ dysfunctions, and the etiology of neurologic disease

Geoeconomic variations in epidemiology, ventilation management, and outcomes in invasively ventilated intensive care unit patients without acute respiratory distress syndrome: a pooled analysis of four observational studies

Background: Geoeconomic variations in epidemiology, the practice of ventilation, and outcome in invasively ventilated intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) remain unexplored. In this analysis we aim to address these gaps using individual patient data of four large observational studies. Methods: In this pooled analysis we harmonised individual patient data from the ERICC, LUNG SAFE, PRoVENT, and PRoVENT-iMiC prospective observational studies, which were conducted from June, 2011, to December, 2018, in 534 ICUs in 54 countries. We used the 2016 World Bank classification to define two geoeconomic regions: middle-income countries (MICs) and high-income countries (HICs). ARDS was defined according to the Berlin criteria. Descriptive statistics were used to compare patients in MICs versus HICs. The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. Secondary outcomes were key ventilation parameters (tidal volume size, positive end-expiratory pressure, fraction of inspired oxygen, peak pressure, plateau pressure, driving pressure, and respiratory rate), patient characteristics, the risk for and actual development of acute respiratory distress syndrome after the first day of ventilation, duration of ventilation, ICU length of stay, and ICU mortality. Findings: Of the 7608 patients included in the original studies, this analysis included 3852 patients without ARDS, of whom 2345 were from MICs and 1507 were from HICs. Patients in MICs were younger, shorter and with a slightly lower body-mass index, more often had diabetes and active cancer, but less often chronic obstructive pulmonary disease and heart failure than patients from HICs. Sequential organ failure assessment scores were similar in MICs and HICs. Use of LTVV in MICs and HICs was comparable (42·4% vs 44·2%; absolute difference -1·69 [-9·58 to 6·11] p=0·67; data available in 3174 [82%] of 3852 patients). The median applied positive end expiratory pressure was lower in MICs than in HICs (5 [IQR 5-8] vs 6 [5-8] cm H2O; p=0·0011). ICU mortality was higher in MICs than in HICs (30·5% vs 19·9%; p=0·0004; adjusted effect 16·41% [95% CI 9·52-23·52]; p<0·0001) and was inversely associated with gross domestic product (adjusted odds ratio for a US$10 000 increase per capita 0·80 [95% CI 0·75-0·86]; p<0·0001). Interpretation: Despite similar disease severity and ventilation management, ICU mortality in patients without ARDS is higher in MICs than in HICs, with a strong association with country-level economic status