We conducted a systematic review to determine the diagnostic accuracy of whole genome sequencing (WGS) of Mycobacterium tuberculosis for the detection of resistance to first- and second-line ...anti-tuberculosis (TB) drugs.
The study was conducted according to the criteria of the Preferred Reporting Items for Systematic Reviews group. A total of 20 publications were included. The sensitivity, specificity, positive-predictive value and negative-predictive value of WGS using phenotypic drug susceptibility testing methods as a reference standard were determined.
Anti-TB agents tested included all first-line drugs, a variety of reserve drugs, as well as new drugs. Polymorphisms in a total of 53 genes were tested for associations with drug resistance. Pooled sensitivity and specificity values for detection of resistance to selected first-line drugs were 0.98 (95% CI 0.93–0.98) and 0.98 (95% CI 0.98–1.00) for rifampicin and 0.97 (95% CI 0.94–0.99) and 0.93 (95% CI 0.91–0.96) for isoniazid, respectively. Due to high heterogeneity in study designs, lack of data, knowledge of resistance mechanisms and clarity on exclusion of phylogenetic markers, there was a significant variation in analytical performance of WGS for the remaining first-line, reserved drugs and new drugs.
Whole genome sequencing could be considered a promising alternative to existing phenotypic and molecular drug susceptibility testing methods for rifampicin and isoniazid pending standardization of analytical pipelines. To ensure clinical relevance of WGS for detection of M. tuberculosis complex drug resistance, future studies should include information on clinical outcomes.
The next generation of bolometric experiments searching for rave events, in particular for the neutrino-less double beta decay, needs fast, high-sensitivity and easy-to-scale cryogenic light ...detectors. The CALDER project (2014–2020) developed a new technology for light detection at cryogenic temperature. In this paper we describe the achievements and the final prototype of this project, consisting of a
5
×
5
cm
2
,
650
μ
m
thick silicon substrate coupled to a single kinetic inductance detector made of a three-layer aluminum-titanium-aluminum. The baseline energy resolution is
34
±
1
(stat)
±
2
(syst) eV RMS and the response time is
120
μ
s. These features, along with the natural multiplexing capability of kinetic inductance detectors, meet the requirements of future large-scale experiments.
As quantum coherence times of superconducting circuits have increased from nanoseconds to hundreds of microseconds, they are currently one of the leading platforms for quantum information processing. ...However, coherence needs to further improve by orders of magnitude to reduce the prohibitive hardware overhead of current error correction schemes. Reaching this goal hinges on reducing the density of broken Cooper pairs, so-called quasiparticles. Here, we show that environmental radioactivity is a significant source of nonequilibrium quasiparticles. Moreover, ionizing radiation introduces time-correlated quasiparticle bursts in resonators on the same chip, further complicating quantum error correction. Operating in a deep-underground lead-shielded cryostat decreases the quasiparticle burst rate by a factor thirty and reduces dissipation up to a factor four, showcasing the importance of radiation abatement in future solid-state quantum hardware.
Radioactivity was recently discovered as a source of decoherence and correlated errors for the real-world implementation of superconducting quantum processors. In this work, we measure levels of ...radioactivity present in a typical laboratory environment (from muons, neutrons, and
γ
-rays emitted by naturally occurring radioactive isotopes) and in the most commonly used materials for the assembly and operation of state-of-the-art superconducting qubits. We present a GEANT-4 based simulation to predict the rate of impacts and the amount of energy released in a qubit chip from each of the mentioned sources. We finally propose mitigation strategies for the operation of next-generation qubits in a radio-pure environment.
We present the performances of a 330 g zinc molybdate (ZnMoO
4
) crystal working as scintillating bolometer as a possible candidate for a next generation experiment to search for neutrinoless double ...beta decay of
100
Mo. The energy resolution, evaluated at the 2615 keV
γ
-line of
208
Tl, is 6.3 keV FWHM. The internal radioactive contaminations of the ZnMoO
4
were evaluated as <6 μBq/kg (
228
Th) and 27±6 μBq/kg (
226
Ra). We also present the results of the
α
vs
β
/
γ
discrimination, obtained through the scintillation light as well as through the study of the shape of the thermal signal alone.
Background model of the CUPID-0 experiment Azzolini, O.; Beeman, J. W.; Bellini, F. ...
The European physical journal. C, Particles and fields,
07/2019, Letnik:
79, Številka:
7
Journal Article
Recenzirano
Odprti dostop
CUPID-0 is the first large mass array of enriched Zn
82
Se scintillating low temperature calorimeters, operated at LNGS since 2017. During its first scientific runs, CUPID-0 collected an exposure of ...9.95 kg year. Thanks to the excellent rejection of
α
particles, we attained the lowest background ever measured with thermal detectors in the energy region where we search for the signature of
82
Se
neutrinoless double beta decay. In this work we develop a model to reconstruct the CUPID-0 background over the whole energy range of experimental data. We identify the background sources exploiting their distinctive signatures and we assess their extremely low contribution down to
∼
10
-
4
counts/(keV kg year) in the region of interest for
82
Se
neutrinoless double beta decay search. This result represents a crucial step towards the comprehension of the background in experiments based on scintillating calorimeters and in next generation projects such as CUPID.
The most sensitive process able to probe the Majorana nature of neutrinos and discover Lepton Number Violation is the neutrino-less double beta decay. Thanks to the excellent energy resolution, ...efficiency and intrinsic radio-purity, cryogenic calorimeters are primed for the search for this process. A novel approach able to improve the sensitivity of the current experiments is the rejection of α interactions, that represents the dominant background source. In TeO2 calorimeters, α particles can be tagged as, in contrast to electrons, they do not emit Cherenkov light. Nevertheless, the very low amount of detected Cherenkov light undermines the complete rejection of α background.
In this paper we compare the results obtained in previous measurements of the TeO2 light yield with a detailed Monte Carlo simulation able to reproduce the number of Cherenkov photons produced in β/γ interactions within the calorimeter and their propagation in the experimental set-up. We demonstrate that the light yield detectable from a 5 × 5 × 5 cm3 TeO2 bolometer can be increased by up to 60% by increasing the surface roughness of the crystal and improving the light detector design.
Moreover, we study the possibility to disentangle α, β and γ interactions, which represent the ultimate background source. Unfortunately γ rejection is not feasible but α rejection can be achieved exploiting high sensitivity light detectors.
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