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The Q & U Bolometric Interferometer for Cosmology (QUBIC) is a cosmology experiment that aims to measure the B-mode polarization of the cosmic microwave background (CMB). Measurements of the primordial B-mode pattern of the CMB polarization are in fact among the most exciting goals in cosmology as it would allow testing of the inflationary paradigm. Many experiments are attempting to measure the B-modes, from the ground and the stratosphere, using imaging Stokes polarimeters. The QUBIC collaboration developed an innovative concept to measure CMB polarization using bolometric interferometry. This approach mixes the high sensitivity of bolometric detectors with the accurate control of systematics due to the interferometric layout of the instrument. We present the calibration results for the Technological Demonstrator, before its commissioning in the Argentinian observing site and preparation for first light.

QUBIC is a ground-based experiment aiming to measure the B-mode polarization of the cosmic microwave background. The developed instrument is an innovative two-frequency band bolometric interferometer that will operate at 300 mK with NbSi TES arrays. In this paper, we describe the fabrication process of the detectors.

Q & U Bolometric Interferometer for Cosmology (QUBIC) is an international ground-based experiment dedicated in the measurement of the polarized fluctuations of the Cosmic Microwave Background. It is based on bolometric interferometry, an original detection technique which combines the immunity to systematic effects of an interferometer with the sensitivity of low-temperature incoherent detectors. QUBIC will be deployed in Argentina, at the Alto Chorrillos mountain site near San Antonio de los Cobres, in the Salta Province. The QUBIC detection chain consists in 2048 NbSi transition edge sensors (TESs) cooled to 350 mK.The voltage-biased TESs are read out with time domain multiplexing based on Superconducting QUantum Interference Devices at 1 K and a novel SiGe application-specific integrated circuit at 60 K allowing to reach an unprecedented multiplexing factor equal to 128. The QUBIC experiment is currently being characterized in the laboratory with a reduced number of detectors before upgrading to the full instrument. I will present the last results of this characterization phase with a focus on the detectors and readout system.

The Q & U Bolometric Interferometer for Cosmology, QUBIC, is an innovative experiment designed to measure the polarization of the cosmic microwave background and in particular the signature left therein by the inflationary expansion of the Universe. The expected signal is extremely faint; thus, extreme sensitivity and systematic control are necessary in order to attempt this measurement. QUBIC addresses these requirements using an innovative approach combining the sensitivity of transition-edge sensor cryogenic bolometers, with the deep control of systematics characteristic of interferometers. This makes QUBIC unique with respect to others' classical imagers experiments devoted to the CMB polarization. In this contribution, we report a description of the QUBIC instrument including recent achievements and the demonstration of the bolometric interferometry performed in laboratory. QUBIC will be deployed at the observation site in Alto Chorrillos, in Argentina, at the end of 2019.

The Q&U Bolometric Interferometer for Cosmology (QL’BIC) is the first bolometric interferometer designed to measure the primordial B-mode polarization of the Cosmic Microwave Background (CMB). Bolometric interferometry is a novel technique that combines the sensitivity of bolometric detectors with the control of systematic effects that is typical of interferometry, both key features in the quest for the faint signal of the primordial B-modes. A unique feature is the so-called “spectral imaging”, i.e., the ability to recover the sky signal in several sub-bands within the physical band during data analysis. This feature provides an in-band spectral resolution of ∆v/v ~ 0.04 that is unattainable by a traditional imager. This is a key tool for controlling the Galactic foregrounds contamination. In this paper, we describe the principles of bolometric interferometry, the current status of the QU BIC experiment and future prospects.

Measurements of cosmic microwave background (CMB) polarization may reveal the presence of a background of gravitational waves produced during cosmic inflation, providing thus a test of inflationary models. The Q&U Bolometric Interferometer for Cosmology (QUBIC) is an experiment designed to measure the CMB polarization. It is based on the novel concept of bolometric interferometry, which combines the sensitivity of bolometric detectors with the properties of beam synthesis and control of calibration offered by interferometers. To modulate and extract the input polarized signal of the CMB, QUBIC exploits Stokes polarimetry based on a rotating half-wave plate (HWP). In this work, we illustrate the design of the QUBIC instrument, focusing on the polarization modulation system, and we present preliminary results of beam calibrations and the performance of the HWP rotator at 300 K.

Background A fast, physician-independent, sensitive, reproducible tool for assessment of disease activity would be useful in rheumatoid arthritis (RA) clinical practice. Objectives This study aimed to compare a new technique, optical spectral transmission imaging (OST), and clinical examination with colour Doppler (CD) ultrasound as gold standard reference. Primary outcomes were sensitivity and specificity of OST for joint inflammation at joint level, and correlations of the summation of joint scores at patient level. Methods This cross-sectional study included 62 RA patients, 50 with ≥1 clinically swollen joint in the hands or wrists and 12 patients without tender or swollen joints. Joint examination, patient global VAS, HAQ and CRP were registered. OST was obtained by Hemics Full Hand Proto at two wavelengths (660nm and 810nm) before, during and after the inflation of a pressure cuff to 50 mm Hg for 60 seconds (total duration of examination 1.5 minutes). OST scores for each joint were based on a previously developed algorithm aimed to mimic a combination of Doppler and grey-scale synovitis, using a predefined cutoff of 0.521 for inflammatory activity. A GE Logiq® E9 US machine with a 5-16ML linear array transducer and Doppler setting optimized for slow flow was used for grading CD activity (0-3) in wrist joints, metacarpophalangeal joints (MCPs) and proximal interphalangeal joints (PIPs). CD activity ≥1 was used as gold standard for inflammation. CD, OST and clinical data were obtained separately and blinded to other data. Results CD activity ≥1 was observed in 167 (12%) of 1364 joints. An OST score larger than the predefined cut-off of 0.521 was found in 343 (25%) joints. AUC of the ROC curve of OST score vs. the gold standard reference was 0.690, p<0.001. For all joints, using cut-offs of 0.145 (wrists)/0.103 (MCPs)/0.697 (PIPs) as optimized for a sensitivity of 75% for the individual joint areas, specificity was 42%. Using cut-offs of 0.525/0.951/1.293 as optimized for a specificity of 90% for the individual joint areas, sensitivity was 23%. Table 1. Sensitivity, specificity and kappa values of OST score and clinical examination compared to CD activity ≥1 as gold standard OST score >0.521 Swollen Tender Sens. Spec. Kappa Sens. Spec. Kappa Sens. Spec. Kappa All joints 54% 79% 0.23 41% 93% 0.35 34% 91% 0.25 Only PIPs 29% 89% 0.09 48% 95% 0.29 33% 94% 0.17 Only MCPs 44% 75% 0.15 36% 93% 0.32 25% 91% 0.17 Only Wrists 91% 24% 0.12 49% 77% 0.27 56% 71% 0.26 At the patient level, the OST score correlated with CD (rho=0.28, p=0.03), patient global VAS (rho=0.31, p=0.02), DAS28 (rho=0.29, p=0.02) and HAQ (rho=0.26, p=0.04). Using new cutoffs as described above, we found even tighter correlations at the patient level with CD (rho=0.31, p=0.01), SJC (rho=0.28, p=0.03), patient global VAS (rho=0.41, p=0.001), CRP (rho=0.29, p=0.03), DAS28 (rho=0.40, p=0.001) and HAQ (rho=0.48, p<0.001). Conclusions Significant correlations with clinical and CD measures of joint inflammation documented the construct validity of OST assessment of joint inflammation. However, with CD as gold standard reference, OST did not demonstrate improved sensitivity and specificity compared to clinical joint examination. Further analyses of the data, including ultrasound grey-scale synovitis, are pending. After further development, OST may be a feasible technique for quick, physician-independent, non-invasive assessment of joint inflammation in RA. Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.4364

Abstract Background Antibiotic use (ABU) surveillance in healthcare facilities (HCFs) is essential to guide stewardship. Two methods are recommended: antibiotic consumption (ABC), expressed as the number of DDD/1000 patient-days; and prevalence of antibiotic prescription (ABP) measured through point prevalence surveys. However, no evidence is provided about whether they lead to similar conclusions. Objectives To compare ABC and ABP regarding HCF ranking and their ability to identify outliers. Methods The comparison was made using 2012 national databases from the antibiotic surveillance network and prevalence study. HCF rankings according to each method were compared with Spearman’s correlation coefficient. Analyses included the ABU from entire HCFs as well as according to type, clinical ward and by antibiotic class and specific molecule. Results A total of 1076 HCFs were included. HCF rankings were strongly correlated in the whole cohort. The correlation was stronger for HCFs with a higher number of beds or with a low or moderate proportion of acute care beds. ABU correlation between ABC or ABP was globally moderate or weak in specific wards. Furthermore, the two methods did not identify the same outliers, whichever HCF characteristics were analysed. Correlation between HCF ranking varied according to the antibiotic class. Conclusions Both methods ranked HCFs similarly overall according to ABC or ABP; however, major differences were observed in ranking of clinical wards, antibiotic classes and detection of outliers. ABC and ABP are two markers of ABU that could be used as two complementary approaches to identify targets for improvement.

QUBIC is a unique instrument that crosses the barriers between classical imaging architectures and interferometry taking advantage from both high sensitivity and systematics mitigation. The scientific target is to detect primordial gravitational waves created by inflation by the polarization they imprint on the cosmic microwave background—the holy grail of modern cosmology. In this paper, we show the latest advances in the development of the architecture and the sub-systems of the first module of this instrument to be deployed at Dome Charlie Concordia base—Antarctica in 2015.