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Introduction To improve the utilization of continuous- and flash glucose monitoring (CGM/FGM) data we have tested the hypothesis that a machine learning (ML) model can be trained to identify the most likely root causes for hypoglycemic events. Methods CGM/FGM data were collected from 449 patients with type 1 diabetes. Of the 42,120 identified hypoglycemic events, 5041 were randomly selected for classification by two clinicians. Three causes of hypoglycemia were deemed possible to interpret and later validate by insulin and carbohydrate recordings: (1) overestimated bolus (27%), (2) overcorrection of hyperglycemia (29%) and (3) excessive basal insulin presure (44%). The dataset was split into a training (n = 4026 events, 304 patients) and an internal validation dataset (n = 1015 events, 145 patients). A number of ML model architectures were applied and evaluated. A separate dataset was generated from 22 patients (13 ‘known’ and 9 ‘unknown’) with insulin and carbohydrate recordings. Hypoglycemic events from this dataset were also interpreted by five clinicians independently. Results Of the evaluated ML models, a purpose-built convolutional neural network (HypoCNN) performed best. Masking the time series, adding time features and using class weights improved the performance of this model, resulting in an average area under the curve (AUC) of 0.921 in the original train/test split. In the dataset validated by insulin and carbohydrate recordings (n = 435 events), i.e. ‘ground truth,’ our HypoCNN model achieved an AUC of 0.917. Conclusions The findings support the notion that ML models can be trained to interpret CGM/FGM data. Our HypoCNN model provides a robust and accurate method to identify root causes of hypoglycemic events.

The mutual neutralisation of O+ with O- has been studied in a double ion-beam storage ring with combined merged-beams, imaging and timing techniques. Branching ratios were measured at the collision energies of 55, 75 and 170 (+/- 15) meV, and found to be in good agreement with previous single-pass merged-beams experimental results at 7 meV collision energy. Several previously unidentified spectral features were found to correspond to mutual neutralisation channels of the first metastable state of the cation (O+(D-2(o)), tau approximate to 3.6 hours), while no contributions from the second metastable state (O+(P-2(o)), tau approximate to 5 seconds) were observed. Theoretical calculations were performed using the multi-channel Landau-Zener model combined with the anion centered asymptotic method, and gave good agreement with several experimentally observed channels, but could not describe well observed contributions from the O+(D-2(o)) metastable state as well as channels involving the O(3s S-5(o)) state.

We present experimental final-state distributions for Mg atoms formed in Mg+ + D- mutual neutralization reactions at center-of-mass collision energies of 59 +/- 12 meV by using the merged-beams method. Comparisons with available full-quantum results reveal large discrepancies and a previously underestimated total rate coefficient by up to a factor of 2 in the 0-1 eV (< 10(4) K) regime. Asymptotic model calculations arc shown to describe the process much better and we recommend applying this method to more complex iron group systems; data that is of urgent need in stellar spectral modeling.

The mutual neutralisation of O

The present paper reports on a merged-beam experiment on mutual neutralization between ${\mathrm{Na}}^{+}$ and ${\mathrm{D}}^{\ensuremath{-}}$. For this experiment, we have used the DESIREE ion-beams storage-ring facility. The reaction products are detected using a position- and time-sensitive detector, which ideally allows for determination of the population of each individual quantum state in the final atomic systems. Here, the $4s, 3d$, and $4p$ final states in Na are observed and in all cases the D atom is in its ground state $1s ^{2}S$. The respective branching fractions of the states populated in Na are determined by fitting results from a Monte Carlo simulation of the experiment to the measured data. The center-of-mass collision energy is controlled using a set of biased drift tubes, and the branching fractions are measured for energies between 80 meV and 393 meV. The resulting branching fractions are found to agree qualitatively with the only available theoretical calculations for this particular system, which are based on a multichannel Landau-Zener approach using dynamic couplings determined with a linear combination of atomic orbitals model.

The EU Disaster Risk Management Knowledge Centre (DRMKC)[1] is currently developing a WebGIS-based platform – the Risk Data Hub[2] - aimed at improving access to and sharing of EU-wide risk data, tools, and methodologies in support to policy Directorate-General and national authorities for their Disaster Risk Management. The development of the platform is based on the results of a ‘’Needs and Gaps” analysis performed as part of the preparation of the European Commission Staff Working Document – ‘’Overview of Natural and Man-made Disaster Risks the European Union may face’’ (2014[3], 2017[4],2020[5]). The overview concerned the 31 summaries of the National Risk Assessment (NRA) submitted to the European Commission by the Participant States of the Union of Civil Protection Mechanism. For multi-hazard assessments, it concluded that a gap exists between the knowledge and data available in the scientific community and the accessibility and usability by Decision Makers and the Civil Protection community. With the DRMKC’s Risk Data Hub development, we support the integration of multi-hazard risk assessment and mapping into evidence-based decision-making, risk-reduction strategies, and adaptation plans.Based on this context and utilizing spatial analysis of exposed elements to various hazards across Europe, we present in this study a novel methodological approach for the assessment of multi-hazard potential impact. This methodology is currently implemented on the DRMKC Risk Data Hub WebGIS platform. The methodological approach is based on a hotspot analysis applied to residential area and population exposed to single hazards such as river flood, coastal inundation, earthquakes, landslides, forest fire, and subsidence. Based on different aggregations of the exposure we identify the statistically significant hotspot for the considered hazard exposure. Using Stouffer’s method (Stouffer et al., 1949) for meta-analysis, the statistically significant exposure hotspots for single hazards are combined and subsequently, spatial extension and location of multi-hazards potential impact can be identified. Consequently, we provide the spatial overview of regions expected to suffer significant multi-hazard potential impacts across Europe at the subnational level. Based on theoretical aspects developed in the literature, we put forward a multi-hazard interaction framework for the sub-national spatial extent across Europe. Finally, a validation of the results against the multi-hazard disaster loss data hosted on the DRMKC Risk Data Hub will be exercised.The outcome of this study will provide valuable input for the Disaster Risk Management policy support and will assist national authorities on the implementation of a multi-hazard approach in the National Risk Assessments preparation. [1] https://drmkc.jrc.ec.europa.eu/ [2] https://drmkc.jrc.ec.europa.eu/risk-data-hub#/ [3] EUR-Lex - 52014SC0134 - EN - EUR-Lex (europa.eu) [4] https://ec.europa.eu/echo/sites/echo-site/files/swd_2017_176_overview_of_risks_2.pdf [5] https://ec.europa.eu/echo/sites/echo-site/files/overview_of_natural_and_man-made_disaster_risks_the_european_union_may_face.pdf Stouffer, S., DeVinney, L. & Suchman, E. 1949. The American soldier: Adjustment during army life, vol. 1. Princeton University Press Princeton, US.

The properties of atomic negative ions are to a large extent determined by electron-electron correlation which makes them an ideal testing ground for atomic many-body physics. In this paper, we present a detailed experimental and theoretical study of excited states in the negative ion of iridium. The ions were stored at cryogenic temperatures using the double electrostatic ion ring experiment facility at Stockholm University. Laser photodetachment was used to monitor the relaxation of three bound excited states belonging to the [Xe] 4f145d86s2 ionic ground configuration. Our measurements show that the first excited state has a lifetime much longer than the ion-beam storage time of 1230±100s. The binding energy of this state was measured to be 1.045±0.002eV. The lifetimes of the second and third excited states were experimentally determined to be 133±10 and 172±35ms, respectively. Multiconfiguration Dirac-Hartree-Fock calculations were performed in order to extract binding energies and lifetimes. These calculations predict the existence of the third excited bound state that was detected experimentally. The computed lifetimes for the three excited bound states agree well with the experimental results and allow for a clear identification of the detected levels., SCOPUS: ar.j, info:eu-repo/semantics/published

Synopsis The electronic structure and the fragmentation dynamics of a series of isolated cyclic-dipeptides (cyclo-Ala-Ala; cyclo-Gly-Ala; cyclo-Gly-Gly) have been studied by mass spectrometry, photoemission and photoelectron-photoion coincidence spectroscopy.

We have developed an experimental technique to study charge-and energy-flow processes in sub-eV collisions between oppositely charged, internally cold, ions of atoms, molecules, and clusters. Two ion beams are stored in separate rings of the cryogenic ion-beam storage facility DESIREE, and merged in a common straight section where a set of biased drift tubes is used to control the center-of-mass collision energy locally in fine steps. Here, we present measurements on mutual neutralization between Li+ and D- where a time-sensitive imaging-detector system is used to measure the three-dimensional distance between the neutral Li and D atoms as they reach the detector. This scheme allows for direct measurements of kinetic-energy releases, and here it reveals separate populations of the 3s state and the (3p + 3d) states in neutral Li while the D atom is left in its ground state 1s. The branching fraction of the 3s final state is measured to be 57.8 +/- 0.7% at a center-of-mass collision energy of 78 +/- 13 meV. The technique paves the way for studies of charge-, energy-, and mass-transfer reactions in single collisions involving molecular and cluster ions in well-defined quantum states.

An overview of recent experimental results of studies of negative atomic and molecular ions in the Double ElectroStatic Ion-Ring ExpEriment, DESIREE is given. Metastable level lifetimes in atomic negative ions have been measured by time-dependent laser photodetachment. Rotational relaxation of diatomic anions is studied by near-threshold photodetachment. Spontaneous decays of small metal cluster anions by electron emission and fragmentation is studied with decay-channel specificity. Finally, mutual neutralisation of pairs of negative and positive ions has been investigated with initial and final state selectivity.

We report the first experimental evidence of spontaneous electron emission from a homonuclear dimer anion through direct measurements of ${\text{Ag}}_{2}^{\ensuremath{-}}\ensuremath{\rightarrow}{\text{Ag}}_{2}+{e}^{\ensuremath{-}}$ decays on milliseconds and seconds timescales. This observation is very surprising as there is no avoided crossing between adiabatic energy curves to mediate such a process. The process is weak, yet dominates the decay signal after 100 ms when ensembles of internally hot ${\mathrm{Ag}}_{2}^{\ensuremath{-}}$ ions are stored in the cryogenic ion-beam storage ring, DESIREE, for 10 s. The electron emission process is associated with an instantaneous, very large reduction of the vibrational energy of the dimer system. This represents a dramatic deviation from a Born-Oppenheimer description of dimer dynamics.

Ultraslow radiative cooling lifetimes and adiabatic detachment energies for three astrochemically relevant anions, C

Advances in merged-beams instruments have allowed experimental studies of the mutual neutralisation (MN) processes in collisions of both Li$^+$ and Na$^+$ ions with D$^-$ at energies below 1 eV. These experimental results place constraints on theoretical predictions of MN processes of Li$^+$ and Na$^+$ with H$^-$, important for non-LTE modelling of Li and Na spectra in late-type stars. We compare experimental results with calculations for methods typically used to calculate MN processes, namely the full quantum (FQ) approach, and asymptotic model approaches based on the linear combination of atomic orbitals (LCAO) and semi-empirical (SE) methods for deriving couplings. It is found that FQ calculations compare best overall with the experiments, followed by the LCAO, and the SE approaches. The experimental results together with the theoretical calculations, allow us to investigate the effects on modelled spectra and derived abundances and their uncertainties arising from uncertainties in the MN rates. Numerical experiments in a large grid of 1D model atmospheres, and a smaller set of 3D models, indicate that neglect of MN can lead to abundance errors of up to 0.1 dex (26\%) for Li at low metallicity, and 0.2 dex (58\%) for Na at high metallicity, while the uncertainties in the relevant MN rates as constrained by experiments correspond to uncertainties in abundances of much less than 0.01~dex (2\%). This agreement for simple atoms gives confidence in the FQ, LCAO and SE model approaches to be able to predict MN with the accuracy required for non-LTE modelling in stellar atmospheres., Comment: Accepted by ApJ

In a national project, with the aim to develop a robust method for structural verification of pressure equipment subjected to ratcheting, a two-rod test approach is developed. Two testing machines, with one specimen in each, are controlled in such way that a constant primary load and a cyclic secondary load are applied on the specimens. The ferritic steel P265 and the austenitic steel 316L are tested for a number of load combinations. Test results show that ratcheting is produced in all tests. As expected, the amount of ratcheting increases with the load level. At the start of a two-rod test, structural ratcheting dominates over material ratcheting. Depending on the load level and combination of primary load and cyclic secondary load, material ratcheting might eventually become more important. Based on results from tensile testing and fully-reversed strain controlled cycling, five different constitutive models are calibrated. The possibility to simulate the response of the conducted experiments with the different models is investigated. The most advanced model investigated, i.e. the nonlinear kinematic Chaboche model, does not necessarily give the best predictions. Up to a strain level of 5%, i.e. the criterion in ASME NB-3228.4, the bi-linear model best predicts the experiments. Recommendations for how ratcheting in structures subjected to cyclic plastic deformation can be predicted by numerical simulation are given.

Synopsis Anions of iridium were stored in the cryogenic storage ring, DESIREE [1, 2, 3] and investigated using laser photodetachment. The ions were stored for up to 2000 seconds and the relaxation of several metastable states were studied by selecting different photon energies. The threshold of the previously not observed 3P2 level is located and the lifetime of this sate is found to be longer than the storage time of the ion beam. We also find that a state exists higher in energy than the previously known level with a lifetime in the range of hundreds of milliseconds.

Synopsis The decay of hot copper dimer anions is studied in a cryogenic storage ring. We detect atomic anion and neutral products and determine the fragmentation and vibrational autodetachment (VAD) rates separately. For short storage times the dimer anions predominantly decay by fragmentation of highly rotationally excited ions by tunneling through the rotational barrier. For storage times exceeding 100 ms, however, VAD is dominating. This process is driven by the very weak direct coupling between nuclear and electronic degrees of freedom.

Spontaneous decays of small, hot silver-cluster anions ${\text{Ag}}_{n}^{\ensuremath{-}}$, $n=4--7$, have been studied using one of the rings of the Double ElectroStatic Ion Ring ExpEriment (DESIREE). Observation of these decays over very long time scales is possible due to the very low residual gas pressure ($\ensuremath{\sim}{10}^{\ensuremath{-}14}$) and cryogenic (13 K) operation of DESIREE. The yield of neutral particles from stored beams of ${\text{Ag}}_{6}^{\ensuremath{-}}$ and ${\text{Ag}}_{7}^{\ensuremath{-}}$ anions were measured for 100 milliseconds and were found to follow single power-law behavior with millisecond time-scale exponential cutoffs. The ${\text{Ag}}_{4}^{\ensuremath{-}}$ and ${\text{Ag}}_{5}^{\ensuremath{-}}$ anions were stored for 60 s and the observed decays show two-component power-law behaviors. We present calculations of the rate constants for electron detachment from and fragmentation of ${\text{Ag}}_{4}^{\ensuremath{-}}$ and ${\text{Ag}}_{5}^{\ensuremath{-}}$. In these calculations, we assume that the internal energy distribution of the clusters are flat and with this we reproduce the early steep parts of the experimentally measured decay curves for ${\text{Ag}}_{4}^{\ensuremath{-}}$ and ${\text{Ag}}_{5}^{\ensuremath{-}}$, which extends to tens and hundreds of milliseconds, respectively. The fact that the calculations reproduce the early slopes of ${\text{Ag}}_{4}^{\ensuremath{-}}$ and ${\text{Ag}}_{5}^{\ensuremath{-}}$, which differ for the two cases, suggests that it is the changes in fragmentation rates with internal cluster energies of ${\text{Ag}}_{4}^{\ensuremath{-}}$ and ${\text{Ag}}_{5}^{\ensuremath{-}}$ rather than conditions in the ion source that determine this behavior. Comparisons with the measurements strongly suggest that the neutral particles detected in these time domains originate from ${\text{Ag}}_{4}^{\ensuremath{-}}\ensuremath{\rightarrow}{\text{Ag}}_{3}^{\ensuremath{-}}+\text{Ag}$ and ${\text{Ag}}_{5}^{\ensuremath{-}}\ensuremath{\rightarrow}{\text{Ag}}_{3}^{\ensuremath{-}}+{\mathrm{Ag}}_{2}$ fragmentation processes.

A sputter ion source with a solid graphite target has been used to produce dianions with a focus on carbon cluster dianions, $\text{C}_{n}^{2-}$, with $n=7-24$. Singly and doubly charged anions from the source were accelerated together to kinetic energies of 10 keV per atomic unit of charge and injected into one of the cryogenic (13 K) ion-beam storage rings of the Double ElectroStatic Ion Ring Experiment facility at Stockholm University. Spontaneous decay of internally hot $\text{C}_{n}^{2-}$ dianions injected into the ring yielded $\text{C}^{-}$ anions with kinetic energies of 20 keV, which were counted with a microchannel plate detector. Mass spectra produced by scanning the magnetic field of a $90^{\circ}$ analyzing magnet on the ion injection line reflect the production of internally hot $\text{C}_{7}^{2-}-\text{C}_{24}^{2-}$ dianions with lifetimes in the range of tens of microseconds to milliseconds. In spite of the high sensitivity of this method, no conclusive evidence of $\text{C}_{6}^{2-}$ was found while there was a clear $\text{C}_{7}^{2-}$ signal with the expect isotopic distribution. An upper limit is deduced for a $\text{C}_{6}^{2-}$ signal that is two orders-of-magnitue smaller than that for $\text{C}_{7}^{2-}$. In addition, $\text{C}_{n}\text{O}^{2-}$ and $\text{CsCu}^{2-}$ dianions were detected., Comment: 6 pages, 6 figures

We apply near-threshold laser photodetachment to characterize the rotational quantum level distribution of OH- ions stored in the cryogenic ion-beam storage ring DESIREE at Stockholm University. We ...

We have measured the spontaneous neutral particle emission from copper-cluster anions (${\mathrm{Cu}}_{n}{}^{\ensuremath{-}}, n=3--6$) stored at cryogenic temperatures in one of the electrostatic ion storage rings of the Double ElectroStatic Ion Ring ExpEriment facility at Stockholm University. The measured rate of emission from the stored ${\mathrm{Cu}}_{3}{}^{\ensuremath{-}}$ ions follows a single power-law decay for about 1 ms but then decreases much more rapidly with time. The latter behavior may be due to a decrease in the density of available final states in ${\mathrm{Cu}}_{3}$ as the excitation energies of the decaying ions approach the electron detachment threshold. The emissions from ${\mathrm{Cu}}_{4}{}^{\ensuremath{-}}, {\mathrm{Cu}}_{5}{}^{\ensuremath{-}}$, and ${\mathrm{Cu}}_{6}{}^{\ensuremath{-}}$ are well described by sums of two power laws that are quenched by radiative cooling of the stored ions with characteristic times between a few and hundreds of milliseconds. We relate these two-component behaviors to populations of stored ions with higher and lower angular momenta. In a separate experiment, we studied the laser-induced decay of ${\mathrm{Cu}}_{6}{}^{\ensuremath{-}}$ ions that were excited by 1.13- or 1.45-eV photons after 46 ms of storage.

Ultraslow radiative cooling lifetimes and adiabatic detachment energies for three astrochemically relevant anions, Cn- (n = 3-5), are measured using the Double ElectroStatic Ion Ring ExpEriment (DESIREE) infrastructure at Stockholm University. DESIREE maintains a background pressure of approximate to 10(-14) mbar and temperature of approximate to 13 K, allowing storage of mass-selected ions for hours and providing conditions coined a "molecular cloud in a box." Here, we construct two-dimensional (2D) photodetachment spectra for the target anions by recording photodetachment signal as a function of irradiation wavelength and ion storage time (seconds to minute time scale). Ion cooling lifetimes, which are associated with infrared radiative emission, are extracted from the 2D photodetachment spectrum for each ion by tracking the disappearance of vibrational hot-band signal with ion storage time, giving 1e cooling lifetimes of 3.1 +/- 0.1 s (C3-), 6.8 +/- 0.5 s (C4-), and 24 +/- 5 s (C5-). Fits of the photodetachment spectra for cold ions, i.e., those stored for at least 30 s, provide adiabatic detachment energies in good agreement with values from laser photoelectron spectroscopy on jet-cooled anions, confirming that radiative cooling has occurred in DESIREE. Ion cooling lifetimes are simulated using a simple harmonic cascade model, finding good agreement with experiment and providing a mode-by-mode understanding of the radiative cooling properties. The 2D photodetachment strategy and radiative cooling modeling developed in this study could be applied to investigate the ultraslow cooling dynamics of a wide range of molecular anions.

The intrinsic radiative lifetimes of the $5{d}^{10}6{s}^{}^{2}S_{1/2}$ and $5{d}^{9}6{s}^{2} ^{2}D_{3/2}$ bound excited states in the platinum anion ${\text{Pt}}^{\ensuremath{-}}$ have been studied at cryogenic temperatures at the Double ElectroStatic Ion Ring Experiment (DESIREE) facility at Stockholm University. The intrinsic lifetime of the higher-lying $5{d}^{10}6{s}^{} ^{2}S_{1/2}$ state was measured to be $2.54\ifmmode\pm\else\textpm\fi{}0.10\phantom{\rule{0.16em}{0ex}}\mathrm{s}$, while only a lifetime in the range of 50\char21{}200 ms could be estimated for the $5{d}^{9}6{s}^{2} ^{2}D_{3/2}$ fine-structure level. The storage lifetime of the ${\text{Pt}}^{\ensuremath{-}}$ ion beam was measured to be a little over 15 min at a ring temperature of $13\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. The present study reports the lifetime of an atomic negative ion in an excited bound state with an electron configuration different from that of the ground state.

This paper describes the principle of load cell monitoring in Gas Centrifuge Enrichment Plants (GCEPs) and how this technique can be implemented in order to improve nuclear safeguards in these kinds of installations. We present a few different possibilities of exploitation of the data that can be obtained by acquiring in continuous mode the weights of the cylinders in the feed and withdrawal (F/W) stations and how to derive conclusions concerning the operation of the plant (conformity or not with respect to “normal” operation). Furthermore the different diversion scenarios for GCEP are discussed and we show how mass monitoring techniques can contribute to detect each of them. Finally we resume the advantages and limitations of the technique and outline some important practical issues concerning the implementation of process monitoring in GCEP, in particular for what concerns the inspectorate/operator relationships. Load cell monitoring could play an important role in the safeguard implementation of future GCEPs.