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Building a quantum computer is one of the outstanding contemporary goals in physics. Trapped-ion qubits are among the most promising contenders, achieving the highest precision gates out of all platforms. However entangling gates have previously only been performed in a regime where their speed is limited by the motion of the ions in the trap. The work in this thesis demonstrates entangling operations beyond this speed limit. In addition, entanglement of different species of ion has been performed. This is an important step towards building a scalable quantum computer, by being able to interface and connect trapped ion qubits via photonic links. We demonstrate mixed-species entangling gates using a method that requires only a single laser for both species. In an experiment demonstrating the technique with two isotopes of calcium, 40Ca+ and 43Ca+ , we achieved a Bell state fidelity of F = 99.8(6)%. We also perform a Bell test with the two different isotopes, achieving a violation of the CHSH inequality by 15 standard deviations with CHSH parameter S = 2.228(15), without making a fair-sampling assumption. We then use the same gate mechanism to perform an entangling gate on two different atomic species, 43Ca+ and 88Sr+ . In a proof-of-principle experiment we achieved a Bell state fidelity of F = 83(3)%. For achieving faster two-qubit gates we shape the amplitude of the laser pulses driving the gates. The pulse shapes are specifically designed to yield low error rates and be insensitive to the optical phase of the driving field. We perform an entangling gate with fidelity F = 99.78(3)% in tg = 1.6 μs, a factor of 20 − 60 times faster than the previously highest-fidelity trapped ion gates with only a factor ≈ 2 increase in gate error. We also demonstrate entanglement generation within 480 ns, less than a single period of the centre-of-mass motion of the ions.

Cette recherche part du constat d’une faible participation à, et d’un maigre contenu dans Wikipedia Arabe et questionne les obstacles à un contenu plus riche. La problématique de la recherche est double: d’abord proposer une cartographie numérique de Wikipedia dans la région du Moyen-Orient et Afrique du Nord. Cette cartographie informe d’une part sur la représentation des participants à Wikipedia Arabe, et d’autre part, sur la contribution à la distribution du savoir arabe et de son étendue. Deuxièmement, la recherche s’intéresse au contenu de Wikipedia arabe et de son mode de production. Plus particulièrement, les questions de recherche portent sur la participation à la production de contenu de Wikipedia Arabe, les barrières à l’entrée dans Wikipedia Arabe, les dynamiques de négociation et de consensus entre éditeurs et administrateurs Wikipediens de la région et les solutions envisagées pour améliorer et encourager la production de contenu. La démarche méthodologique est principalement qualitative.So far Arabic content on Wikipedia Arabic is very weak; this paper questions the barriers that prevent contributors to Wikipedia Arabic from being more active in content production on Wikipedia Arabic. The research problematic is twofold: first, it suggests a digital cartography of Wikipedia in the MENA region that informs about those who represent Wikipedia Arabic and thus, contribute to the Arab knowledge distribution. Second, while adopting a qualitative approach, the research looks at the content of Arabic Wikipedia. It questions its production methods, contribution barriers, dynamics of negotiation between Wikipedians, and strategies of consensus between editors and admins, as well as the envisioned solutions to improve and promote Wikipedia Arabic content production.

Objectives To define chronic ultrasound lesions of the axillary artery (AA) in long-standing giant cell arteritis (GCA) and to evaluate the reliability of the new ultrasound definition in a web-based exercise. Methods A structured Delphi, involving an expert panel of the Large Vessel Vasculitis subgroup of the Outcome Measures in Rheumatology (OMERACT) Ultrasound Working Group was carried out. The reliability of the new definition was tested in a 2-round web-based exercise involving 23 experts and using 50 still images each from AA of long-standing and acute GCA patients, as well as 50 images from healthy individuals. Results The final OMERACT ultrasound definition of chronic changes was based on measurement and appearance of the intima-media complex. The overall reliability of the new definition for chronic ultrasound changes in longstanding GCA of the AA was good to excellent with Light's kappa values of 0.79-0.80 for inter-reader reliability and mean Light's-kappa of 0.88 for intra-reader reliability. The mean inter-rater and intra-rater agreements were 86-87% and 92%, respectively. Good reliabilities were observed comparing the vessels with longstanding versus acute GCA with a mean agreement and kappa values of 81% and 0.63, respectively. Conclusion The new OMERACT ultrasound definition for chronic vasculitis of the AA in GCA revealed a good to excellent inter- and intra-reader reliability in a web-based exercise of experts.

Purpose Approximately 1–2% of chronic myeloid leukemia (CML) patients harbor atypical BCR-ABL1 transcripts that cannot be monitored by real-time quantitative PCR (RT-qPCR) using standard methodologies. Within the European Treatment and Outcome Study (EUTOS) for CML we established and validated robust RT-qPCR methods for these patients. Methods BCR-ABL1 transcripts were amplified and sequenced to characterize the underlying fusion. Residual disease monitoring was carried out by RT-qPCR with specific primers and probes using serial dilutions of appropriate BCR-ABL1 and GUSB plasmid DNA calibrators. Results were expressed as log reduction of the BCR-ABL1/GUSB ratio relative to the patient-specific baseline value and evaluated as an individual molecular response (IMR). Results In total, 330 blood samples (2–34 per patient, median 8) from 33 CML patients (19 male, median age 62 years) were analyzed. Patients expressed seven different atypical BCR-ABL1 transcripts (e1a2, n = 6; e6a2, n = 1; e8a2, n = 2; e13a3, n = 4; e14a3, n = 6; e13a3/e14a3, n = 2; e19a2, n = 12). Most patients (61%) responded well to TKI therapy and achieved an IMR of at least one log reduction 3 months after diagnosis. Four patients relapsed with a significant increase of BCR-ABL1/GUSB ratios. Conclusions Characterization of atypical BCR-ABL1 transcripts is essential for adequate patient monitoring and to avoid false-negative results. The results cannot be expressed on the International Scale (IS) and thus the common molecular milestones and guidelines for treatment are difficult to apply. We, therefore, suggest reporting IMR levels in these cases as a time-dependent log reduction of BCR-ABL1 transcript levels compared to baseline prior to therapy.

ObjectivesTo develop an Outcome Measures in Rheumatology (OMERACT) ultrasonography score for monitoring disease activity in giant cell arteritis (GCA) and evaluate its metric properties.MethodsThe OMERACT Instrument Selection Algorithm was followed. Forty-nine members of the OMERACT ultrasonography large vessel vasculitis working group were invited to seven Delphi rounds. An online reliability exercise was conducted using images of bilateral common temporal arteries, parietal and frontal branches as well as axillary arteries from 16 patients with GCA and 7 controls. Sensitivity to change and convergent construct validity were tested using data from a prospective cohort of patients with new GCA in which ultrasound-based intima–media thickness (IMT) measurements were conducted at weeks 1, 3, 6, 12 and 24.ResultsAgreement was obtained (92.7%) for the OMERACT GCA Ultrasonography Score (OGUS), calculated as follows: sum of IMT measured in every segment divided by the rounded cut-off values of IMTs in each segment. The resulting value is then divided by the number of segments available. Thirty-five members conducted the reliability exercise, the interrater intraclass correlation coefficient (ICC) for the OGUS was 0.72–0.84 and the median intrareader ICC was 0.91. The prospective cohort consisted of 52 patients. Sensitivity to change between baseline and each follow-up visit up to week 24 yielded standardised mean differences from −1.19 to −2.16, corresponding to large and very large magnitudes of change, respectively. OGUS correlated moderately with erythrocyte sedimentation rate, C reactive protein and Birmingham Vasculitis Activity Score (corrcoeff0.37–0.48).ConclusionWe developed a provisional OGUS for potential use in clinical trials.

Objective.To test the reliability of Outcome Measures in Rheumatology Clinical Trials (OMERACT) consensus-based ultrasound definitions for normal and vasculitic temporal and axillary arteries in patients with giant cell arteritis (GCA) and in controls.Methods.A preliminary 1-day meeting and a full 3-day meeting fulfilling OMERACT Ultrasound Group guidelines were held. Temporal and axillary arteries were examined at 2 timepoints by 12 sonographers on 4 patients with GCA and 2 controls. The aim was to test inter- and intrareader reliability for normal findings, halo sign, and compression sign. In both meetings, patients had established GCA. Pathology was more recent in the full meeting, which was preceded by 6 h of training. Scanning time was 15–20 min instead of 10–13 min.Results.In the preliminary exercise, interreader reliabilities were fair to moderate for the overall diagnosis of GCA (Light κ 0.29–0.51), and poor to fair for identifying vasculitis in the respective anatomical segments (Light κ 0.02–0.46). Intrareader reliabilities were moderate (Cohen κ 0.32–0.64). In the main exercise, interreader reliability was good to excellent (Light κ 0.76–0.86) for the overall diagnosis of GCA, and moderate to good (Light κ 0.46–0.71) for identifying vasculitis in the respective anatomical segments. Intrareader reliability was excellent for diagnosis of GCA (Cohen κ 0.91) and good (Cohen κ 0.71–0.80) for the anatomical segments.Conclusion.OMERACT-derived definitions of halo and compression signs of temporal and axillary arteries are reliable in recent-onset GCA if experienced sonographers (> 300 examinations) have 15–20 min for a standardized examination with prior training and apply > 15 MHz probes.

Cette recherche part du constat d’une faible participation à, et d’un maigre contenu dans Wikipedia Arabe et questionne les obstacles à un contenu plus riche. La problématique de la recherche est double: d’abord proposer une cartographie numérique de Wikipedia dans la région du Moyen-Orient et Afrique du Nord. Cette cartographie informe d’une part sur la représentation des participants à Wikipedia Arabe, et d’autre part, sur la contribution à la distribution du savoir arabe et de son étendue. Deuxièmement, la recherche s’intéresse au contenu de Wikipedia arabe et de son mode de production. Plus particulièrement, les questions de recherche portent sur la participation à la production de contenu de Wikipedia Arabe, les barrières à l’entrée dans Wikipedia Arabe, les dynamiques de négociation et de consensus entre éditeurs et administrateurs Wikipediens de la région et les solutions envisagées pour améliorer et encourager la production de contenu. La démarche méthodologique est principalement qualitative.So far Arabic content on Wikipedia Arabic is very weak; this paper questions the barriers that prevent contributors to Wikipedia Arabic from being more active in content production on Wikipedia Arabic. The research problematic is twofold: first, it suggests a digital cartography of Wikipedia in the MENA region that informs about those who represent Wikipedia Arabic and thus, contribute to the Arab knowledge distribution. Second, while adopting a qualitative approach, the research looks at the content of Arabic Wikipedia. It questions its production methods, contribution barriers, dynamics of negotiation between Wikipedians, and strategies of consensus between editors and admins, as well as the envisioned solutions to improve and promote Wikipedia Arabic content production.