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1.
Blood Rev ; 65: 101172, 2024 May.
Article in English | MEDLINE | ID: mdl-38267313

ABSTRACT

The vast spectrum of aggressive B-cell non-Hodgkin neoplasms (B-NHL) encompasses several infrequent entities occurring in association with viral infections, posing diagnostic challenges for practitioners. In the emerging era of precision oncology, the molecular characterization of malignancies has acquired paramount significance. The pathophysiological comprehension of specific entities and the identification of targeted therapeutic options have seen rapid development. However, owing to their rarity, not all entities have undergone exhaustive molecular characterization. Considerable heterogeneity exists in the extant body of work, both in terms of employed methodologies and the scale of cases studied. Presently, therapeutic strategies are predominantly derived from observations in diffuse large B-cell lymphoma (DLBCL), the most prevalent subset of aggressive B-NHL. Ongoing investigations into the molecular profiles of these uncommon virus-associated entities are progressively facilitating a clearer distinction from DLBCL, ultimately paving the way towards individualized therapeutic approaches. This review consolidates the current molecular insights into aggressive and virus-associated B-NHL, taking into consideration the recently updated 5th edition of the WHO classification of hematolymphoid tumors (WHO-5HAEM) and the International Consensus Classification (ICC). Additionally, potential therapeutically targetable susceptibilities are highlighted, offering a comprehensive overview of the present scientific landscape in the field.


Subject(s)
Lymphoma, Large B-Cell, Diffuse , Lymphoma, Non-Hodgkin , Humans , Precision Medicine , Lymphoma, Large B-Cell, Diffuse/pathology
2.
Phys Rev Lett ; 131(2): 022501, 2023 Jul 14.
Article in English | MEDLINE | ID: mdl-37505957

ABSTRACT

The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.

5.
Phys Rev Lett ; 124(4): 042503, 2020 Jan 31.
Article in English | MEDLINE | ID: mdl-32058764

ABSTRACT

There is sparse direct experimental evidence that atomic nuclei can exhibit stable "pear" shapes arising from strong octupole correlations. In order to investigate the nature of octupole collectivity in radium isotopes, electric octupole (E3) matrix elements have been determined for transitions in ^{222,228}Ra nuclei using the method of sub-barrier, multistep Coulomb excitation. Beams of the radioactive radium isotopes were provided by the HIE-ISOLDE facility at CERN. The observed pattern of E3 matrix elements for different nuclear transitions is explained by describing ^{222}Ra as pear shaped with stable octupole deformation, while ^{228}Ra behaves like an octupole vibrator.

6.
Nat Commun ; 10(1): 2473, 2019 06 06.
Article in English | MEDLINE | ID: mdl-31171788

ABSTRACT

There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in 224Rn and 226Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment.

7.
Phys Rev Lett ; 121(14): 142701, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-30339438

ABSTRACT

The ^{12}C(α,γ)^{16}O reaction plays a central role in astrophysics, but its cross section at energies relevant for astrophysical applications is only poorly constrained by laboratory data. The reduced α width, γ_{11}, of the bound 1^{-} level in ^{16}O is particularly important to determine the cross section. The magnitude of γ_{11} is determined via sub-Coulomb α-transfer reactions or the ß-delayed α decay of ^{16}N, but the latter approach is presently hampered by the lack of sufficiently precise data on the ß-decay branching ratios. Here we report improved branching ratios for the bound 1^{-} level [b_{ß,11}=(5.02±0.10)×10^{-2}] and for ß-delayed α emission [b_{ßα}=(1.59±0.06)×10^{-5}]. Our value for b_{ßα} is 33% larger than previously held, leading to a substantial increase in γ_{11}. Our revised value for γ_{11} is in good agreement with the value obtained in α-transfer studies and the weighted average of the two gives a robust and precise determination of γ_{11}, which provides significantly improved constraints on the ^{12}C(α,γ) cross section in the energy range relevant to hydrostatic He burning.

8.
Phys Rev Lett ; 121(25): 252501, 2018 Dec 21.
Article in English | MEDLINE | ID: mdl-30608829

ABSTRACT

The first 2^{+} and 3^{-} states of the doubly magic nucleus ^{132}Sn are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The ^{132}Sn ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a ^{206}Pb target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0_{g.s.}^{+}→2_{1}^{+}, 0_{g.s.}^{+}→3_{1}^{-}, and 2_{1}^{+}→3_{1}^{-} in ^{132}Sn. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0_{g.s.}^{+}→2_{1}^{+}) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of ^{132}Sn.

9.
Occup Med (Lond) ; 67(7): 546-554, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-29016982

ABSTRACT

BACKGROUND: Burnout in healthcare is a worldwide problem. However, most studies focus narrowly on work-related factors and outcomes in one health profession or speciality. AIMS: To investigate the prevalence of burnout and its association with job demands, job resources, individual well-being, work-related attitudes and behaviour in physicians and nurses across different specialties. METHODS: Multi-centre cross-sectional study of physicians and nurses working in Belgian hospitals. An electronic questionnaire was used to assess job demands (e.g. workload), job resources (e.g. autonomy) and indicators of well-being, work-related attitudes and behaviours. Structural equation modelling was used to examine interrelationships between explanatory variables and outcomes. RESULTS: 1169 physicians and 4531 nurses participated; response rate 26%. High scores (>75th percentile in reference group of Dutch health care workers) were seen in 6% of the sample on three burnout dimensions (i.e. emotional exhaustion, depersonalization and personal competence) and in 13% for at least two dimensions. In contrast to the other dimensions, emotional exhaustion strongly related to almost all variables examined in the model. Positive associations were seen with workload, role conflicts, emotional burden and work-home interference and negative associations with learning and development opportunities and co-worker support. Emotional exhaustion correlated negatively with well-being, turnover intention, being prepared and able to work until retirement age, medication use, absenteeism and presenteeism. CONCLUSIONS: Work-related factors were critical correlates of emotional exhaustion, which strongly related to poor health and turnover intention. Randomized controlled trials are suggested to underpin the effectiveness of interventions tackling job stressors and promoting job resources.


Subject(s)
Burnout, Professional/etiology , Nurses/psychology , Physicians/psychology , Adult , Attitude of Health Personnel , Belgium , Burnout, Professional/psychology , Chi-Square Distribution , Cross-Sectional Studies , Female , Humans , Job Satisfaction , Male , Middle Aged , Prevalence , Psychometrics/instrumentation , Psychometrics/methods , Stress, Psychological/etiology , Stress, Psychological/psychology , Surveys and Questionnaires , Workplace/psychology , Workplace/standards
10.
Phys Rev Lett ; 118(22): 222501, 2017 Jun 02.
Article in English | MEDLINE | ID: mdl-28621970

ABSTRACT

Fast-neutron-induced fission of ^{238}U at an energy just above the fission threshold is studied with a novel technique which involves the coupling of a high-efficiency γ-ray spectrometer (MINIBALL) to an inverse-kinematics neutron source (LICORNE) to extract charge yields of fission fragments via γ-γ coincidence spectroscopy. Experimental data and fission models are compared and found to be in reasonable agreement for many nuclei; however, significant discrepancies of up to 600% are observed, particularly for isotopes of Sn and Mo. This indicates that these models significantly overestimate the standard 1 fission mode and suggests that spherical shell effects in the nascent fission fragments are less important for low-energy fast-neutron-induced fission than for thermal neutron-induced fission. This has consequences for understanding and modeling the fission process, for experimental nuclear structure studies of the most neutron-rich nuclei, for future energy applications (e.g., Generation IV reactors which use fast-neutron spectra), and for the reactor antineutrino anomaly.

12.
Phys Rev Lett ; 116(2): 022701, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26824536

ABSTRACT

Neutron-rich {96,98}Sr isotopes have been investigated by safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility. Reduced transition probabilities and spectroscopic quadrupole moments have been extracted from the differential Coulomb excitation cross sections. These results allow, for the first time, the drawing of definite conclusions about the shape coexistence of highly deformed prolate and spherical configurations. In particular, a very small mixing between the coexisting states is observed, contrary to other mass regions where strong mixing is present. Experimental results have been compared to beyond-mean-field calculations using the Gogny D1S interaction in a five-dimensional collective Hamiltonian formalism, which reproduce the shape change at N=60.

13.
J Mech Behav Biomed Mater ; 56: 1-5, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26651062

ABSTRACT

Spider orb-webs are designed to allow for quick energy absorption as well as the constraint of drastic oscillations occurring upon prey impact. Studies on spider silk illustrate its impressive mechanical properties and its capacity to be used as technical fibers in composite materials. Models have previously been used to study the mechanical properties of different silk fibers, but not the behavior of the spider web as a whole. Full spider webs have been impacted by a projectile and the transverse displacement was measured by means of a laser interferometer. The damping and stiffness of the entire webs were quantified considering the orb-web as a single-degree-of-freedom (SDOF) system. The amplitude, the period duration, and the energy dissipation of the oscillations have also been reported from the experiments. The analysis of the energy dissipation confirmed that the webs of orb-web spiders are optimized for the capture of a single or few large prey, rather than several small prey. The experiments also confirmed that the overall stiffness of the web displayed a non-linear behavior. Such non-linearity was also observed in the damping characteristics of the webs studied.


Subject(s)
Spiders , Vibration , Animals , Biomechanical Phenomena , Models, Biological , Predatory Behavior
14.
Phys Rev Lett ; 115(17): 172501, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26551106

ABSTRACT

Excited states of the neutron-rich nuclei (97,99)Rb were populated for the first time using the multistep Coulomb excitation of radioactive beams. Comparisons of the results with particle-rotor model calculations provide clear identification for the ground-state rotational band of (97)Rb as being built on the πg(9/2) [431] 3/2(+) Nilsson-model configuration. The ground-state excitation spectra of the Rb isotopes show a marked distinction between single-particle-like structures below N=60 and rotational bands above. The present study defines the limits of the deformed region around A∼100 and indicates that the deformation of (97)Rb is essentially the same as that observed well inside the deformed region. It further highlights the power of the Coulomb-excitation technique for obtaining spectroscopic information far from stability. The (99)Rb case demonstrates the challenges of studies with very short-lived postaccelerated radioactive beams.

16.
Methods Inf Med ; 54(5): 461-73, 2015.
Article in English | MEDLINE | ID: mdl-26419400

ABSTRACT

OBJECTIVES: Empirical mode decomposition (EMD) is a frequently used signal processing approach which adaptively decomposes a signal into a set of narrow-band components known as intrinsic mode functions (IMFs). For multi-trial, multivariate (multiple simultaneous recordings), and multi-subject analyses the number and signal properties of the IMFs can deviate from each other between trials, channels and subjects. A further processing of IMFs, e.g. a simple ensemble averaging, should determine which IMFs of one signal correspond to IMFs from another signal. When the signal properties have similar characteristics, the IMFs are assigned to each other. This problem is known as correspondence problem. METHODS: From the mathematical point of view, in some cases the correspondence problem can be transformed into an assignment problem which can be solved e.g. by the Kuhn-Munkres algorithm (KMA) by which a minimal cost matching can be found. We use the KMA for solving classic assignment problems, i.e. the pairwise correspondence between two sets of IMFs of equal cardinalities, and for pairwise correspondences between two sets of IMFs with different cardinalities representing an unbalanced assignment problem which is a special case of the k-cardinality assignment problem. RESULTS: A KMA-based approach to solve the correspondence problem was tested by using simulated, heart rate variability (HRV), and EEG data. The KMA-based results of HRV decomposition are compared with those obtained from a hierarchical cluster analysis (state-of-the-art). The major difference between the two approaches is that there is a more consistent assignment pattern using KMA. Integrating KMA into complex analysis concepts enables a comprehensive exploitation of the key advantages of the EMD. This can be demonstrated by non-linear analysis of HRV-related IMFs and by an EMD-based cross-frequency coupling analysis of the EEG data. CONCLUSIONS: The successful application to HRV and EEG analysis demonstrates that our solutions can be used for automated EMD-based processing concepts for biomedical signals.


Subject(s)
Algorithms , Diagnosis, Computer-Assisted/methods , Electroencephalography/methods , Epilepsy/diagnosis , Heart Rate Determination/methods , Signal Processing, Computer-Assisted , Child , Female , Humans , Male , Pattern Recognition, Automated/methods , Regression Analysis , Reproducibility of Results , Sensitivity and Specificity
18.
Clin Neurophysiol ; 126(9): 1769-79, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25670344

ABSTRACT

OBJECTIVE: This study characterized thalamo-cortical communication by assessing the effect of context-dependent modulation on the very early somatosensory evoked high-frequency oscillations (HF oscillations). METHODS: We applied electrical stimuli to the median nerve together with an auditory oddball paradigm, presenting standard and deviant target tones representing differential cognitive contexts to the constantly repeated electrical stimulation. Median nerve stimulation without auditory stimulation served as unimodal control. RESULTS: A model consisting of one subcortical (near thalamus) and two cortical (Brodmann areas 1 and 3b) dipolar sources explained the measured HF oscillations. Both at subcortical and the cortical levels HF oscillations were significantly smaller during bimodal (somatosensory plus auditory) than unimodal (somatosensory only) stimulation. A delay differential equation model was developed to investigate interactions within the 3-node thalamo-cortical network. Importantly, a significant change in the eigenfrequency of Brodmann area 3b was related to the context-dependent modulation, while there was no change in the network coupling. CONCLUSION: This model strongly suggests cortico-thalamic feedback from both cortical Brodmann areas 1 and 3b to the thalamus. With the 3-node network model, thalamo-cortical feedback could be described. SIGNIFICANCE: Frequency encoding plays an important role in contextual modulation in the somatosensory thalamo-cortical network.


Subject(s)
Acoustic Stimulation/methods , Evoked Potentials, Somatosensory/physiology , Nerve Net/physiology , Somatosensory Cortex/physiology , Thalamus/physiology , Adult , Cerebral Cortex/physiology , Electric Stimulation/methods , Female , Humans , Male , Median Nerve/physiology , Psychomotor Performance/physiology
19.
Methods Inf Med ; 54(3): 205-8, 2015.
Article in English | MEDLINE | ID: mdl-24852643

ABSTRACT

INTRODUCTION: This article is part of the Focus Theme of Methods of Information in Medicine on "Biosignal Interpretation: Advanced Methods for Neural Signals and Images". OBJECTIVES: The aim of this study was to compare rhythmicities in the quadratic phase coupling (QPC) in the tracé discontinue EEG patterns (TD) of premature newborns and the tracé alternant EEG patterns (TA) of full-term newborns by means of time-variant bispectral analysis. Both pattern occur during quiet sleep and are characterized by an ongoing sequence of interburst and burst patterns. The courses of time-variant bispectral measures during the EEG burst most likely indicate specific interrelations between cortical and thalamocortical brain structures. METHODS: The EEG of a group of premature (n = 5) and of full-term (n = 5) newborns was analysed. Time-variant QPC was investigated by means of time-variant parametric bispectral analysis. The frequency plain [0.5 Hz, 1.5 Hz] x [3 Hz, 6 Hz] was used as the region-of-interest (ROI). RESULTS: QPC rhythms with a frequency of 0.1 Hz (8 - 11 s) were found in all full-term newborns at all electrodes. For the premature newborns the QPC rhythms were less stable and slower (< 0.1 Hz, 11 -  17 s) at all electrodes and showed a higher inter-individual variation than for the full-term newborns. Statistically, the adaptation of a linear mixed model revealed a difference of about 5 s between both groups of newborns. CONCLUSIONS: The comparison of the results of both groups of newborns indicates a development in the interaction between cortical, thalamocortical and neurovegetative structures in the neonatal brain.


Subject(s)
Electroencephalography/methods , Sleep , Algorithms , Electroencephalography/instrumentation , Humans , Infant, Newborn , Infant, Premature , Linear Models
20.
Cardiovasc Intervent Radiol ; 37(4): 1053-61, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24390361

ABSTRACT

PURPOSE: To evaluate heating efficacy of superparamagnetic iron oxide nanoparticles (SPIO) for electromagnetic ablation (EMA) of osteoid osteoma (OO) using an ex vivo model compared to radiofrequency ablation (RFA) and microwave ablation (MWA). METHODS: A model for OO using sliced bovine tibia and sliced muscle tissue was developed. A bone cavity filled with either a mixture of SPIO and agarose or pure agarose (control group) was established. EMA was performed using an experimental system, RFA and MWA using clinically approved systems, and the ablation protocols recommended by the vendor. For temperature measurements, fiberoptic temperature probes were inserted inside the cavity, on the outside of the periosteum, and at a 5 mm distance to the periosteum. RESULTS: Maximum temperatures with or without SPIO in the nidus were as follows: EMA: 79.9 ± 2.5/22.3 ± 0.7 °C; RFA: 95.1 ± 1.8/98.6 ± 0.9 °C; MWA: 85.1 ± 10.8/83.4 ± 9.62 °C. In RFA with or without SPIO significantly higher temperatures were achieved in the nidus compared to all other groups (p < 0.05). In MWA significantly higher temperatures were observed in the 5 mm distance to the periosteum compared to EMA and RFA with or without SPIO (p < 0.05). In MWA temperature decrease between nidus and the 5 mm distance to the periosteum was significantly lower than in RFA with or without SPIO (p < 0.0001). In MWA without SPIO temperature decrease was significantly lower than in the EMA group (p < 0.05). CONCLUSION: In the experimental setting, ablation of OO is safe and effective using EMA. It is less invasive than RFA and MWA, and it theoretically allows repeated treatments without repeated punctures. In comparison, the highest temperatures in the nidus are reached using RFA.


Subject(s)
Catheter Ablation/methods , Dextrans/pharmacology , Microwaves/therapeutic use , Osteoma, Osteoid/surgery , Animals , Cattle , Disease Models, Animal , Electromagnetic Fields , Equipment Design , Magnetite Nanoparticles , Temperature , Tibia
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