Development of a position-sensitive detector for positronium inertial sensing measurements

In the last twenty years, both free fall and interferometry/deflectometry experiments have been proposed for the measurement of the gravitational acceleration on positronium, which is a purely leptonic matter-antimatter atom formed by an electron and its antiparticle (positron). Among the several challenges posed by these experiments is the development of position-sensitive detectors to measure the deflection of positronium in the Earth's gravitational field. In this work, we describe our recent progress in the development of position-sensitive detectors. Two different detection schemes are considered. The first is based on Ps ionization in a strong homogeneous magnetic field and imaging of the freed positron with a microchannel plate. The second scheme is based on scanning the positronium atom distribution on a plane by moving the slit or a material grating with sub-nm accuracy, and counting the atoms crossing the obstacle and those annihilating on it. The possibility of reaching a spatial resolution of around 15 μm using the former detection scheme is shown, and preliminary steps towards the development of a detector following the latter scheme (with potential position sensitivity in the sub-nm range) are described

Co-design and evaluation of the feasibility and the efficacy of a multiple-targeted adapted physical activity intervention to promote quality of life, well-being and physical activity levels in pregnant women: The “well-done!” study protocol

Background: Regular physical activity (PA) practice during pregnancy offers health and fitness benefits for both mother and baby. Therefore, healthy pregnant women with no contraindi-cations to exercise should be encouraged to perform PA. Nevertheless, their levels of PA are gener-ally low. The aim of the WELL-DONE! Study is to co-design an adapted physical activity intervention (APAI) for pregnant women to include in childbirth preparation classes (CPCs) evaluating its feasibility and efficacy on quality of life (QoL), PA levels and other outcomes. Methods: A quasi-experimental study was divided in two progressive stages. First, APAI was developed in collabo-ration with pregnant women and midwives using focus groups; second, APAI’s efficacy was evaluated comparing two groups: the experimental group engaged in the CPCs integrated with 1 h/week of the APAI administered by midwives and the control group participating in the standard CPCs. Pre-post evaluation was carried out in three stages through questionnaires and tests. Data analysis involved the combination of qualitative and quantitative methodologies. Discussion: Find-ings from the WELL-DONE! Study will help to assess the feasibility, sustainability, and efficacy of incorporating APAI inside CPCs as a new public health strategy oriented to QoL, well-being, and PA level improvements

The AEgIS experiment at CERN: Probing antimatter gravity

The AE¯gIS experiment at CERN’s Antiproton Decelerator is set up to precisely measure the gravitational interaction between matter and antimatter. For this purpose, antihydrogen will be formed from cold antiprotons and positronium, the hydrogen-like bound state of an electron and a positron. Subsequently, the free-fall acceleration of a cold horizontal beam of antihydrogen will be measured by a deflectometer. The present status, recent experimental progress and the medium-term plan of the AE¯gIS experiment are presented

Moral emotions and moral disengagement: concurrent and longitudinal associations with aggressive behavior among early adolescents

The complex temporal associations among moral disengagement, moral emotions, and aggressive behavior were investigated within a short-term four-wave longitudinal study in a sample of early adolescents (at T1: N = 245; Mage= 12.16 years; SD = 0.85). Moral disengagement and aggressive behavior were investigated by validated self-report scales. Shame and guilt were assessed in response to six-story vignettes. A series of four-wave longitudinal mediation analyses were conducted to test several theoretically meaningful models. Mediation models revealed positive reciprocal longitudinal effects between aggressive behavior and moral disengagement. Aggressive behavior negatively predicted moral emotions, and moral disengagement was negatively associated with moral emotions over time. When testing competing models including all three variables in one model, no theoretical meaningful mediation process emerged: Instead, high moral disengagement predicted lower moral emotions but higher aggressive behavior over time. Results are discussed regarding their practical importance for prevention and intervention programs

Using resource graphs to represent conceptual change

We introduce resource graphs, a representation of linked ideas used when reasoning about specific contexts in physics. Our model is consistent with previous descriptions of resources and coordination classes. It can represent mesoscopic scales that are neither knowledge-in-pieces or large-scale concepts. We use resource graphs to describe several forms of conceptual change: incremental, cascade, wholesale, and dual construction. For each, we give evidence from the physics education research literature to show examples of each form of conceptual change. Where possible, we compare our representation to models used by other researchers. Building on our representation, we introduce a new form of conceptual change, differentiation, and suggest several experimental studies that would help understand the differences between reform-based curricula.Comment: 27 pages, 14 figures, no tables. Submitted for publication to the Physical Review Special Topics Physics Education Research on March 8, 200

Annihilation of low energy antiprotons in silicon

The goal of the AE$\mathrm{\bar{g}}$IS experiment at the Antiproton Decelerator (AD) at CERN, is to measure directly the Earth's gravitational acceleration on antimatter. To achieve this goal, the AE$\mathrm{\bar{g}}$IS collaboration will produce a pulsed, cold (100 mK) antihydrogen beam with a velocity of a few 100 m/s and measure the magnitude of the vertical deflection of the beam from a straight path. The final position of the falling antihydrogen will be detected by a position sensitive detector. This detector will consist of an active silicon part, where the annihilations take place, followed by an emulsion part. Together, they allow to achieve 1$$ precision on the measurement of $\bar{g}$ with about 600 reconstructed and time tagged annihilations. We present here, to the best of our knowledge, the first direct measurement of antiproton annihilation in a segmented silicon sensor, the first step towards designing a position sensitive silicon detector for the AE$\mathrm{\bar{g}}$IS experiment. We also present a first comparison with Monte Carlo simulations (GEANT4) for antiproton energies below 5 MeVComment: 21 pages in total, 29 figures, 3 table

Prospects for measuring the gravitational free-fall of antihydrogen with emulsion detectors

The main goal of the AEgIS experiment at CERN is to test the weak equivalence principle for antimatter. AEgIS will measure the free-fall of an antihydrogen beam traversing a moir\'e deflectometer. The goal is to determine the gravitational acceleration g for antihydrogen with an initial relative accuracy of 1% by using an emulsion detector combined with a silicon micro-strip detector to measure the time of flight. Nuclear emulsions can measure the annihilation vertex of antihydrogen atoms with a precision of about 1 - 2 microns r.m.s. We present here results for emulsion detectors operated in vacuum using low energy antiprotons from the CERN antiproton decelerator. We compare with Monte Carlo simulations, and discuss the impact on the AEgIS project.Comment: 20 pages, 16 figures, 3 table

Minimal residual disease after transplantation or lenalidomide-based consolidation in myeloma patients: a prospective analysis

We analyzed 50 patients who achieved at least a very good partial response in the RV-MM-EMN-441 study. Patients received consolidation with autologous stem-cell transplantation (ASCT) or cyclophosphamide-lenalidomide-dexamethasone (CRD), followed by Lenalidomide-based maintenance. We assessed minimal residual disease (MRD) by multi-parameter flow cytometry (MFC) and allelic-specific oligonucleotide real-time quantitative polymerase chain reaction (ASO-RQ-PCR) after consolidation, after 3 and 6 courses of maintenance, and thereafter every 6 months until progression. By MFC analysis, 19/50 patients achieved complete response (CR) after consolidation, and 7 additional patients during maintenance. A molecular marker was identified in 25/50 patients, 4/25 achieved molecular-CR after consolidation, and 3 additional patients during maintenance. A lower MRD value by MFC was found in ASCT patients compared with CRD patients (p = 0.0134). Tumor burden reduction was different in patients with high-risk vs standard-risk cytogenetics (3.4 vs 5.2, ln-MFC; 3 vs 6 ln-PCR, respectively) and in patients who relapsed vs those who did not (4 vs 5, ln-MFC; 4.4 vs 7.8 ln-PCR). MRD progression anticipated clinical relapse by a median of 9 months while biochemical relapse by a median of 4 months. MRD allows the identification of a low-risk group, independently of response, and a better characterization of the activity of treatments