Spins in silicon quantum devices are promising candidates for large-scale quantum computing. Gate-based sensing of spin qubits offers a compact and scalable readout with high fidelity, however, ...further improvements in sensitivity are required to meet the fidelity thresholds and measurement timescales needed for the implementation of fast feedback in error correction protocols. Here, we combine radio-frequency gate-based sensing at 622 MHz with a Josephson parametric amplifier, that operates in the 500-800 MHz band, to reduce the integration time required to read the state of a silicon double quantum dot formed in a nanowire transistor. Based on our achieved signal-to-noise ratio, we estimate that singlet-triplet single-shot readout with an average fidelity of 99.7% could be performed in 1 μs, well below the requirements for fault-tolerant readout and 30 times faster than without the Josephson parametric amplifier. Additionally, the Josephson parametric amplifier allows operation at a lower radio-frequency power while maintaining identical signal-to-noise ratio. We determine a noise temperature of 200 mK with a contribution from the Josephson parametric amplifier (25%), cryogenic amplifier (25%) and the resonator (50%), showing routes to further increase the readout speed.
The superconductor-ferromagnet proximity effect describes the fast decay of a spin-singlet supercurrent originating from the superconductor upon entering the neighboring ferromagnet. After placing a ...conical magnet (holmium) at the interface between the two, we detected a long-ranged supercurrent in the ferromagnetic layer. The long-range effect required particular thicknesses of the spiral magnetically ordered holmium, consistent with spin-triplet proximity theory. This enabled control of the electron pairing symmetry by tuning the degree of magnetic inhomogeneity through the thicknesses of the holmium injectors.
Ferromagnetism and conventional singlet superconductivity can be regarded as competing ordering phenomena. A considerable body of theoretical work over the past twenty years has predicted that at ...interfaces between the two systems competition or coupling between superconducting and magnetic phenomena are possible. Despite the very short lengthscales over which some of the phenomena exist, many of these predictions have been experimentally realized. The aim of this topical review is to provide an overview of the experimental position and to discuss the potential developments and applications of existing results.
Allelic loss in chromosome 3p is one of the most frequent and earliest genetic events in lung carcinogenesis. We investigated if the loss of microRNA-128b, a microRNA located on chromosome 3p and a ...putative regulator of epidermal growth factor receptor (EGFR), correlated with response to targeted EGFR inhibition. Loss of microRNA-128b would be equivalent to losing a tumor suppressor gene because it would allow increased expression of EGFR.
We initially showed that microRNA-128b is a regulator of EGFR in non-small-cell lung cancer (NSCLC) cell lines. We tested microRNA-128b expression levels by quantitative RT–PCR, genomic copy number by quantitative PCR, and mutations in the mature microRNA-128b by sequencing. We determined whether microRNA-128b loss of heterozygosity (LOH) in 58 NSCLC patient samples correlated with response to gefitinib and evaluated EGFR expression and mutation status.
We determined that microRNA-128b directly regulates EGFR. MicroRNA-128b LOH was frequent in tumor samples and correlated significantly with clinical response and survival following gefitinib. EGFR expression and mutation status did not correlate with survival outcome.
Identifying microRNA regulators of oncogenes could have far-reaching implications for lung cancer patients including improving patient selection for targeted agents, development of novel therapeutics, or development as early biomarkers of disease.
In 1933, Meissner and Ochsenfeld reported the expulsion of magnetic flux—the diamagnetic Meissner effect—from the interior of superconducting lead. This discovery was crucial in formulating the ...Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity. In exotic superconducting systems BCS theory does not strictly apply. A classical example is a superconductor-magnet hybrid system where magnetic ordering breaks time-reversal symmetry of the superconducting condensate and results in the stabilization of an odd-frequency superconducting state. It has been predicted that under appropriate conditions, odd-frequency superconductivity should manifest in the Meissner state as fluctuations in the sign of the magnetic susceptibility, meaning that the superconductivity can either repel (diamagnetic) or attract (paramagnetic) external magnetic flux. Here, we report local probe measurements of faint magnetic fields in a Au/Ho/Nb trilayer system using low-energy muons, where antiferromagnetic Ho (4.5 nm) breaks time-reversal symmetry of the proximity-induced pair correlations in Au. From depth-resolved measurements below the superconducting transition of Nb, we observe a local enhancement of the magnetic field in Au that exceeds the externally applied field, thus proving the existence of an intrinsic paramagnetic Meissner effect arising from an odd-frequency superconducting state.
Electrostatic analyzers of different designs have been used since the earliest days of the space age, beginning with the very earliest solar-wind measurements made by Mariner 2 en route to Venus in ...1962. The Parker Solar Probe (PSP) mission, NASA's first dedicated mission to study the innermost reaches of the heliosphere, makes its thermal plasma measurements using a suite of instruments called the Solar Wind Electrons, Alphas, and Protons (SWEAP) investigation. SWEAP's electron PSP Analyzer (Solar Probe ANalyzer-Electron (SPAN-E)) instruments are a pair of top-hat electrostatic analyzers on PSP that are capable of measuring the electron distribution function in the solar wind from 2 eV to 30 keV. For the first time, in situ measurements of thermal electrons provided by SPAN-E will help reveal the heating and acceleration mechanisms driving the evolution of the solar wind at the points of acceleration and heating, closer than ever before to the Sun. This paper details the design of the SPAN-E sensors and their operation, data formats, and measurement caveats from PSP's first two close encounters with the Sun.
Pleural malignant mesothelioma (MM) is a deadly tumour predominantly associated with asbestos exposure. A reliable diagnostic and prognostic marker for MM will significantly enhance clinical care and ...is an area of intense research. Soluble mesothelin is the most studied and an FDA-approved biomarker for MM. A recent report showed promising results using fibulin-3 as a new diagnostic marker. The aim of this study was to compare the utility of fibulin-3 versus mesothelin, singly or in combination.
Fibulin-3 and soluble mesothelin were determined by ELISA in the plasma and pleural fluid of 153 patients presenting with a pleural effusion including 82 with MM, 36 with non-MM malignant effusions and 35 with benign effusions. Biomarker concentrations were determined in the plasma of an additional 49 cases with benign asbestos-related disease.
Mesothelin provides better diagnostic accuracy than fibulin-3 for MM whether measured in plasma or pleural effusion: area under the curve (AUC) for plasma was 0.822 (95% CI 0.76 to 0.87) compared with 0.671 (0.61 to 0.73), respectively, and for pleural fluid AUC was 0.815 (0.74 to 0.87) compared with 0.588 (0.51 to 0.67), respectively. Effusion fibulin-3 was an independent significant prognostic factor for survival in MM patients; HR 2.08 (1.14 to 3.82), p=0.017. MM patients with effusion fibulin-3 levels below the median survived significantly longer than those with levels above the median (14.1 vs 7.9 months, p=0.012). Mesothelin and neutrophil to lymphocyte ratio were not significant prognostic markers.
Soluble mesothelin is a superior diagnostic biomarker for MM compared with fibulin-3, whereas fibulin-3 provides superior prognostic information compared with mesothelin.
Abstract
Materials with strongly correlated electrons often exhibit interesting physical properties. An example of these materials is the layered oxide perovskite Sr
2
RuO
4
, which has been ...intensively investigated due to its unusual properties. Whilst the debate on the symmetry of the superconducting state in Sr
2
RuO
4
is still ongoing, a deeper understanding of the Sr
2
RuO
4
normal state appears crucial as this is the background in which electron pairing occurs. Here, by using low-energy muon spin spectroscopy we discover the existence of surface magnetism in Sr
2
RuO
4
in its normal state. We detect static weak dipolar fields yet manifesting at an onset temperature higher than 50 K. We ascribe this unconventional magnetism to orbital loop currents forming at the reconstructed Sr
2
RuO
4
surface. Our observations set a reference for the discovery of the same magnetic phase in other materials and unveil an electronic ordering mechanism that can influence electron pairing with broken time reversal symmetry.
Abstract
Study question
Does septum resection improve reproductive outcomes in women with a septate uterus?
Summary answer
In women with a septate uterus, septum resection does not increase live ...birth rate nor does it decrease the rates of pregnancy loss or preterm birth, compared with expectant management.
What is known already
The septate uterus is the most common uterine anomaly with an estimated prevalence of 0.2–2.3% in women of reproductive age, depending on the classification system. The definition of the septate uterus has been a long-lasting and ongoing subject of debate, and currently two classification systems are used worldwide. Women with a septate uterus may be at increased risk of subfertility, pregnancy loss, preterm birth and foetal malpresentation. Based on low quality evidence, current guidelines recommend removal of the intrauterine septum or, more cautiously, state that the procedure should be evaluated in future studies.
Study design, size, duration
We performed an international multicentre cohort study in which we identified women mainly retrospectively by searching in electronic patient files, medical records and databases within the time frame of January 2000 until August 2018. Searching of the databases, files and records took place between January 2016 and July 2018. By doing so, we collected data on 257 women with a septate uterus in 21 centres in the Netherlands, USA and UK.
Participants/materials, setting, methods
We included women with a septate uterus, defined by the treating physician, according to the classification system at that time. The women were ascertained among those with a history of subfertility, pregnancy loss, preterm birth or foetal malpresentation or during a routine diagnostic procedure. Allocation to septum resection or expectant management was dependent on the reproductive history and severity of the disease. We excluded women who did not have a wish to conceive at time of diagnosis. The primary outcome was live birth. Secondary outcomes included pregnancy loss, preterm birth and foetal malpresentation. All conceptions during follow-up were registered but for the comparative analyses, only the first live birth or ongoing pregnancy was included. To evaluate differences in live birth and ongoing pregnancy, we used Cox proportional regression to calculate hazard rates (HRs) and 95% CI. To evaluate differences in pregnancy loss, preterm birth and foetal malpresentation, we used logistic regression to calculate odds ratios (OR) with corresponding 95% CI. We adjusted all reproductive outcomes for possible confounders.
Main results and the role of chance
In total, 257 women were included in the cohort. Of these, 151 women underwent a septum resection and 106 women had expectant management. The median follow-up time was 46 months. During this time, live birth occurred in 80 women following a septum resection (53.0%) compared to 76 women following expectant management (71.7%) (HR 0.71 95% CI 0.49–1.02) and ongoing pregnancy occurred in 89 women who underwent septum resection (58.9%), compared to 80 women who had expectant management (75.5%) (HR 0.74 (95% CI 0.52–1.06)). Pregnancy loss occurred in 51 women who underwent septum resection (46.8%) versus 31 women who had expectant management (34.4%) (OR 1.58 (0.81–3.09)), while preterm birth occurred in 26 women who underwent septum resection (29.2%) versus 13 women who had expectant management (16.7%) (OR 1.26 (95% CI 0.52–3.04)) and foetal malpresentation occurred in 17 women who underwent septum resection (19.1%) versus 27 women who had expectant management (34.6%) (OR 0.56 (95% CI 0.24–1.33)).
Limitations, reasons for caution
Our retrospective study has a less robust design compared with a randomized controlled trial. Over the years, the ideas about the definition of the septate uterus has changed, but since the 257 women with a septate uterus included in this study had been diagnosed by their treating physician according to the leading classification system at that time, the data of this study reflect the daily practice of recent decades. Despite correcting for the most relevant patient characteristics, our estimates might not be free of residual confounding.
Wider implications of the findings
Our results suggest that septum resection, a procedure that is widely offered and associated with financial costs for society, healthcare systems or individuals, does not lead to improved reproductive outcomes compared to expectant management for women with a septate uterus. The results of this study need to be confirmed in randomized clinical trials.
Study funding/competing interest(s)
A travel for JFWR to Chicago was supported by the Jo Kolk Studyfund. Otherwise, no specific funding was received for this study. The Department of Obstetrics and Gynaecology, University Medical Centre, Groningen, received an unrestricted educational grant from Ferring Pharmaceutical Company unrelated to the present study. BWM reports grants from NHMRC, personal fees from ObsEva, personal fees from Merck, personal fees from Guerbet, other payment from Guerbet and grants from Merck, outside the submitted work. The other authors declare no conficts of interest.
Trial registration number
N/A
The theory of superconductivity developed by Bardeen, Cooper and Schrieffer (BCS) explains the stabilization of electron pairs into a spin-singlet, even frequency, state by the formation of an energy ...gap within which the density of states is zero. At a superconductor interface with an inhomogeneous ferromagnet, a gapless odd frequency superconducting state is predicted, in which the Cooper pairs are in a spin-triplet state. Although indirect evidence for such a state has been obtained, the gap structure and pairing symmetry have not so far been determined. Here we report scanning tunnelling spectroscopy of Nb superconducting films proximity coupled to epitaxial Ho. These measurements reveal pronounced changes to the Nb subgap superconducting density of states on driving the Ho through a metamagnetic transition from a helical antiferromagnetic to a homogeneous ferromagnetic state for which a BCS-like gap is recovered. The results prove odd frequency spin-triplet superconductivity at superconductor/inhomogeneous magnet interfaces.
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