Characterizing a (high resolution) magnetic separator may not be easy as it is difficult to find a stable ion source providing species with close enough masses to separate. As these instruments ...perform a momentum separation (Bρ=p/q), their mass and energy resolution are strictly the same. One can use this property to characterize the mass resolution of a spectrometer through its energy resolution. Hence, multiple identical beams with close energies can be used to test a magnetic spectrometer in almost real conditions. The method we present allows to populate an ion beam with multiple close and well-defined energies. It consists in using an arbitrary pulse generator to temporally change the acceleration potential of the ion source, and create a custom energy distribution, where the length in time of the pulse is the production ratio of the contaminant and the amplitude its relative energy (i.e. its mass).
Display omitted
Precision mass measurements of 104Y, 106Zr, 104,104m,109Nb, and 111,112Mo have been performed with the JYFLTRAP double Penning trap mass spectrometer at the Ion Guide Isotope Separator On-Line ...facility. The order of the long-lived states in 104Nb was unambiguously established. The trend in two-neutron separation energies around the N=66 neutron midshell appeared to be steeper with respect to the Atomic Mass Evaluation 2020 extrapolations for the 39Y and 40Zr isotopic chains and less steep for the 41Nb chain, indicating a possible gap opening around Z=40. The experimental results were compared to the BSkG2 model calculations performed with and without vibrational and rotational corrections. All of them predict two low-lying minima for 106Zr. While the unaltered BSkG2 model fails to predict the trend in two-neutron separation energies, selecting the more deformed minima in calculations and removing the vibrational correction, the calculations are more in line with experimental data. The same is also true for the 21+ excitation energies and differences in charge radii in the Zr isotopes. The results stress the importance of improved treatment of collective corrections in large-scale models and further development of beyond-mean-field techniques.
The development of respiratory infections secondary to Aspergillus spp. spores found ubiquitously in the ambient environment is uncommon in immunocompetent patients. Previous reports of invasive ...upper airway aspergillosis in immunocompetent patients have generally demonstrated the efficacy of treatment regimens utilizing antifungal agents in combination with periodic endoscopic debridement, with symptoms typically resolving within months of initiating therapy.
A 43-year-old previously healthy female presented with worsening respiratory symptoms after failing to respond to long-term antibiotic treatment of bacterial sinusitis. Biopsy of her nasopharynx and trachea revealed extensive fungal infiltration and Aspergillus fumigatus was isolated on tissue culture. Several months of oral voriconazole monotherapy failed to resolve her symptoms and she underwent mechanical debridement for symptom control. Following transient improvement, her symptoms subsequently returned and failed to fully resolve in spite of increased voriconazole dosing and multiple additional tissue debridements over the course of many years.
Invasive upper airway aspergillosis is exceedingly uncommon in immunocompetent patients. In the rare instances that such infections do occur, combinatorial voriconazole and endoscopic debridement is typically an efficacious treatment approach. However, some patients may continue to experience refractory symptoms. In such cases, continued aggressive treatment may potentially slow disease progression even if complete disease resolution cannot be achieved.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The article describes the commissioning and technical development of the Weak Interaction Studies with 32Ar Decay (WISArD) experiment, installed at the radioactive ion-beam facility ISOLDE/CERN. The ...experiment aims to extend the present limits on scalar and tensor currents in the weak interaction and hence search for physics beyond the Standard Model. The evaluation of these limits relies on measuring the proton energy in beta-delayed proton emission, sensitive to both the beta-neutrino angular correlation coefficient aβν and the Fierz interference term b. The method tries to improve previous studies by considering the positron-proton coincidences when determining the kinematic shift in the energy of the emitted protons. Using this coincidence technique, the aβν and b coefficients will be measured at the per mil level. Simulations were employed to optimize the ion beam transport efficiency and validate proof-of-principle results obtained in November 2018 (Nov2018). Upgrades are ongoing, and we are looking into improvements to the overall performance of the setup.
For the GBAR (Gravitational Behaviour of Antihydrogen at Rest) experiment at CERN’s Antiproton Decelerator (AD) facility we have constructed a source of slow positrons, which uses a low-energy ...electron linear accelerator (linac). The driver linac produces electrons of 9 MeV kinetic energy that create positrons from bremsstrahlung-induced pair production. Staying below 10 MeV ensures no persistent radioactive activation in the target zone and that the radiation level outside the biological shield is safe for public access. An annealed tungsten-mesh assembly placed directly behind the target acts as a positron moderator. The system produces 5×107 slow positrons per second, a performance demonstrating that a low-energy electron linac is a superior choice over positron-emitting radioactive sources for high positron flux.
This contribution presents a precise measurement of the excitation energy of the lowest (0+, T=2) state in 32S. Combined with the mass excesses of the 32S ground state and of the four other members ...of the (A=32,T=2) quintet of analogue states, it allows to test the validity of the Isobaric Multiplet Mass Equation to the third order in Tz, which renders it highly sensitive to the mechanisms inducing isospin mixing in the involved sd-shell nuclei. The (0+, T=2) isobaric analogue state in 32S was resonantly populated in the 31P(p, γ) reaction at ~3.3 MeV incident energy. The measurement procedure, involving high-purity germanium detectors, is described and the preliminary result obtained with a digital data acquisition system is presented.
Abstract
Drinking water supply networks play an essential role in protecting the human and economic wellbeing of the territories they serve. To ensure continued quality of service, organisations ...involved in water infrastructure asset management (WIAM) need to deal with a number of issues related to global change. This paper presents the results of an original interdisciplinary foresight approach carried out by a group of engineering and social scientists, in partnership with a number of stakeholders. The purpose was to examine various possible pathways for the future of a French territory. The full title of our foresight study is: ‘Supplying water destined for human consumption in Nouvelle-Aquitaine (France) up until 2070’. Four scenarios, as contrasted as possible, were designed based on five components: organisation and operation of the water supply service, social demands in terms of drinking water, the governance context, territorial dynamics, and the overall context. We then ran further simulations to visualise what a given infrastructure network would look like under each set of assumptions, and under different territorial configurations. One significant advantage of our foresight approach is the educational value it has for stakeholders and water managers. Foresight makes the future potentially visible and provides an opportunity to discuss it, in order to able to inform decision-making.
This paper evaluates the applicability of a new sampling device for monitoring vinyl chloride monomer (VCM) in drinking water networks. This device consists of an adsorbing cartridge filled with a ...strong adsorbent enclosed between two sheets of polyethylene-polyamide membrane. The passive sampler (PS) combines preconcentration on the cartridge with easy extraction by thermal desorption into a gas chromatograph (GC), coupled with a tandem mass spectrometer (MS/MS). In order to estimate the suitability of the device for monitoring VCM, samplers were calibrated in a hydraulic pilot under controlled parameters. The influences of temperature, flow velocity and variation of exposure concentration were then examined. Linear uptake was observed during a VCM exposure of 12 days and the effect of temperature on the sampling rate was evaluated. This sampling device responds to an aquatic environmental contamination and public health issue. Indeed, it combines the monitoring of an organic volatile contaminant dissolved in water and a sampling approach, which still is rarely used in drinking water networks. It offers complementary monitoring to current techniques, providing a more representative assessment of temporal contamination.
This paper evaluates the applicability of a new sampling device for monitoring vinyl chloride monomer (VCM) in drinking water networks.
Prostatic yolk sac tumour is a germ cell tumour with a wide range of age of occurrence, unusual anatomic locations, diverse morphologic patterns, and aggressive biologic behavior, posing challenges ...both to diagnosis and clinical management. We report a rare case of primary yolk sac tumour of the prostate with extensive local and liver metastasis, the latter of which exhibited sheets of small blue cells expressing CD99 and focal sall4 on biopsy. Positivity for CD99 and gata3 in the initial biopsy raised the differential diagnosis of Ewing sarcoma and poorly differentiated carcinoma. The primary tumour demonstrated an admixture of solid and glandular growth patterns and occasional Schiller-Duval bodies. A panel of immunohistochemical stains showing positivity for AE1/3, sall4, cdx2, and focal alpha-fetoprotein, and negativity for oct-4, facilitated the diagnosis. A thorough review of the literature and our current report indicate that a large tumour load, incomplete tumour resection, limited response to preoperative neoadjuvant chemotherapy, and late stage of the disease are predictive factors for a poor clinical outcome.
The production of antihydrogen ions (H̅
+
) in the
GBAR
experiment will occur via a two step charge exchange process. In a first reaction, the antiprotons(P̅) from the
ELENA
ring will capture a ...positron from a positronium(Ps) target producing antihydrogen (H̅) atoms. Those interacting in the same Ps target will produce in a second step H̅
+
. This results in a dependence for the H̅
+
production rate which is roughly proportional to the Ps density squared. Wepresent a scheme to increase the anti-ion production rate in the
GBAR
experiment by tailoring the antiproton to the positron pulse in order to maximise thetemporal overlap of Ps and p̅. Detailed simulations show that an order of magnitude could be gained by bunching the antiprotons from
ELENA
. In order to avoid losses in their capture in the Paul trap due to the energy spread introducedby the bunching, debunching with a symmetrical inverted pulse can be appliedto the H̅
+
ions.
PDF
