4D-imaging of drip-line radioactivity by detecting proton emission from 54mNi pictured with ACTAR TPC.

Proton radioactivity was discovered exactly 50 years ago. First, this nuclear decay mode sets the limit of existence on the nuclear landscape on the neutron-deficient side. Second, it comprises fundamental aspects of both quantum tunnelling as well as the coupling of (quasi)bound quantum states with the continuum in mesoscopic systems such as the atomic nucleus. Theoretical approaches can start either from bound-state nuclear shell-model theory or from resonance scattering. Thus, proton-radioactivity guides merging these types of theoretical approaches, which is of broader relevance for any few-body quantum system. Here, we report experimental measurements of proton-emission branches from an isomeric state in 54mNi, which were visualized in four dimensions in a newly developed detector. We show that these decays, which carry an unusually high angular momentum, ℓ = 5 and ℓ = 7, respectively, can be approximated theoretically with a potential model for the proton barrier penetration and a shell-model calculation for the overlap of the initial and final wave functions.

Ranula as the First Symptom of HIV Infection in Young Patients.

INTRODUCTION: Oral manifestations are often the earliest HIV signs. Salivary gland diseases are a common form of HIV expression. A ranula can occur in association with HIV. However, this manifestation is rarely considered as the disease sentinel sign. We present two cases of children consulting for a ranula, leading to the diagnosis of a previously unknown HIV infection. Case Reports. Two children, respectively, 5 and 13, were treated for a ranula by marsupialization. Relapse occurred in both cases, and thereafter, a ranula excision was performed. While the follow-up was uneventful, HIV infection was diagnosed during the patients' care. The only sign or symptom observed was the ranula. A routine HIV testing of ranula patients would have allowed earlier care. CONCLUSION: Routine HIV testing of patients with a ranula is justified and may be recommended, especially for children. Ranula excision associated with the sublingual gland resection is suggested in order to avoid recurrence.

Effective rescue treatment with vemurafenib of an infant with high-risk Langerhans cell histiocytosis.

INTRODUCTION: The recently identified role of a BRAF somatic mutation in the pathophysiology of Langerhans cell histiocytosis (LCH) offers new therapeutic options. Herein we describe the case of a 10-month-old infant with refractory high-risk LCH successfully treated with vemurafenib. OBSERVATION: The patient first presented with cutaneous LCH at the age of 2 months. The disease remained undiagnosed until she was 6 months old, when it rapidly evolved to a multisystemic high-risk and life-threatening disease, refractory to 2 lines of chemotherapy. BRAFV600E mutation was found at skin biopsy, and targeted therapy with vemurafenib was started when she was 10 months old. The treatment induced a fast and sustained response, but rapid relapse occurred after treatment discontinuation, leading to resumption of treatment, once more resulting in a sustained response. CONCLUSION: Our case highlights the first-line role of dermatologists in establishing the diagnosis of LCH, especially in children, in whom the eruption may be difficult to identify, leading to delayed diagnosis. Targeted therapy with vemurafenib has recently been described in children in this indication and our results support its efficacy, highlighting the need for prolonged treatment and raising the question of maintenance therapy, as well as the necessity for large-scale and long-term studies.

Two-Proton Radioactivity of

In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from ^{67}Kr. At the same time, no evidence for 2p emission of ^{59}Ge and ^{63}Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to ^{67}Kr as being the best new candidate among the three for two-proton radioactivity. ^{67}Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of ^{67}Kr is 7.4(30) ms.

Observation of the ß-delayed γ-proton decay of (56)Zn and its impact on the Gamow-Teller strength evaluation.

We report the observation of a very exotic decay mode at the proton drip line, the ß-delayed γ-proton decay, clearly seen in the ß decay of the T_{z}=-2 nucleus ^{56}Zn. Three γ-proton sequences have been observed after the ß decay. Here this decay mode, already observed in the sd shell, is seen for the first time in the fp shell. Both γ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.

High flux of relativistic electrons produced in femtosecond laser-thin foil target interactions: characterization with nuclear techniques.

We present a protocol to characterize the high energy electron beam emitted in the interaction of an ultraintense laser with matter at intensities higher than 10(19) W cm(-2). The electron energies and angular distributions are determined as well as the total number of electrons produced above a 10 MeV threshold. This protocol is based on measurements with an electron spectrometer and nuclear activation techniques, combined with Monte Carlo simulations based on the GEANT3 code. The method is detailed and exemplified with data obtained with polypropylene and copper thin solid targets at a laser intensity of 2x10(19) W cm(-2). Special care is taken of the different sources of uncertainties. In particular, the reproducibility of the laser shots is considered.

Fast electron transport and induced heating in solid targets from rear-side interferometry imaging.

Fast adiabatic plasma heating of a thin solid target irradiated by a high intensity laser has been observed by an optical fast interferometry diagnostic. It is driven by the hot electron current induced by the laser plasma interaction at the front side of the target. Radial and longitudinal temperature profiles are calculated to reproduce the observed rear-side plasma expansion. The main parameters of the suprathermal electrons (number, temperature, and divergence) have been deduced from these observations.

Direct evidence of strongly inhomogeneous energy deposition in target heating with laser-produced ion beams.

We report on strong nonuniformities in target heating with intense, laser-produced proton beams. The observed inhomogeneity in energy deposition can strongly perturb equation of state (EOS) measurements with laser-accelerated ions which are planned in several laboratories. Interferometric measurements of the target expansion show different expansion velocities on the front and rear surfaces, indicating a strong difference in local temperature. The nonuniformity indicates at an additional heating mechanism, which seems to originate from electrons in the keV range.