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We develop techniques to probe the dynamics of quantum information, and implement them experimentally on an IBM superconducting quantum processor. Our protocols adapt shadow tomography for the study of time evolution channels rather than of quantum states, and rely only on single-qubit operations and measurements. We identify two unambiguous signatures of quantum information scrambling, neither of which can be mimicked by dissipative processes, and relate these to many-body teleportation. By realizing quantum chaotic dynamics in experiment, we measure both signatures, and support our results with numerical simulations of the quantum system. We additionally investigate operator growth under this dynamics, and observe behaviour characteristic of quantum chaos. As our methods require only a single quantum state at a time, they can be readily applied on a wide variety of quantum simulators., Comment: 14 + 5 pages, 9 figures

Low energy fission of 234,235,236,238U and 237,238Np radioactive beams, provided by the GSI/FRS facility, has been studied using the R3B/SOFIA setup. The latter allows, on an event-by-event basis, to simultaneously identify, in terms of their mass and atomic numbers, the fissioning nucleus in coincidence with both fission fragments after prompt-neutron emission. This presentation reports on new results on elemental, isobaric and isotopic yields.

We argue and numerically substantiate that the real-space entanglement spectrum (RSES) of chiral Abelian quantum Hall states is given by the spectrum of a local boundary perturbation of a (1+1)-dimensional conformal field theory, which describes an effective edge dynamics along the real-space cut. The cut-and-glue approach suggests that the low-lying RSES is equivalent to the low-lying modes of some effective edge action. The general structure of this action is deduced by mapping to a boundary critical problem, generalizing the work of Dubail, Read, and Rezayi [Phys. Rev. B 85, 115321 (2012)]. Using trial wave functions, we numerically test our model of the RSES for the ν=2/3 bosonic composite fermion state.

The long-standing quest to determine the superconducting order of ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ (SRO) has received renewed attention after recent nuclear magnetic resonance (NMR) Knight shift experiments have cast doubt on the possibility of spin-triplet pairing in the superconducting state. As a putative solution, encompassing a body of experiments conducted over the years, a $(d+ig)$-wave order parameter caused by an accidental near degeneracy has been suggested [S. A. Kivelson et al., npj Quantum Mater. 5, 43 (2020)]. Here we develop a general Ginzburg--Landau theory for multiband superconductors. We apply the theory to SRO and predict the relative size of the order parameter components. The heat capacity jump expected at the onset of the second-order parameter component is found to be above the current threshold deduced by the experimental absence of a second jump. Our results tightly restrict theories of $d+ig$ order, and other candidates caused by a near degeneracy, in SRO. We discuss possible solutions to the problem.

Given the high prevalence of multidrug-resistant (MDR)-TB in high HIV burden settings, it is important to identify potential drug-drug interactions between MDR-TB treatment and widely used nucleoside reverse transcriptase inhibitors (NRTIs) in HIV-positive children. Population pharmacokinetic models were developed for lamivudine (n = 54) and abacavir (n = 50) in 54 HIV-positive children established on NRTIs; 27 with MDR-TB (combinations of high-dose isoniazid, pyrazinamide, ethambutol, ethionamide, terizidone, fluoroquinolones, and amikacin), and 27 controls without TB. Two-compartment models with first-order elimination and transit compartment absorption described both lamivudine and abacavir pharmacokinetics, respectively. Allometric scaling with body weight adjusted for the effect of body size. Clearance was predicted to reach half its mature value ∼2 (lamivudine) and ∼3 (abacavir) months after birth, with completion of maturation for both drugs at ∼2 years. No significant difference was found in key pharmacokinetic parameters of lamivudine and abacavir when co-administered with routine drugs used for MDR-TB in HIV-positive children.

There is a need for short and safe all-oral treatment of rifampicin-resistant tuberculosis. We compared outcomes up to 24 months after treatment initiation for patients with rifampicin-resistant tuberculosis in South Africa treated with a short, all-oral bedaquiline-containing regimen (bedaquiline group), or a short, injectable-containing regimen (injectable group).Patients with rifampicin-resistant tuberculosis, aged 18 years or older, eligible for a short regimen starting treatment between Jan 1 and Dec 31, 2017, with a bedaquiline-containing or WHO recommended injectable-containing treatment regimen of 9-12 months, registered in the drug-resistant tuberculosis database (EDRWeb), and with known age, sex, HIV status, and national identification number were eligible for study inclusion; patients receiving linezolid, carbapenems, terizidone or cycloserine, delamanid, or para-aminosalicylic acid were excluded. Bedaquiline was given at a dose of 400 mg once daily for two weeks followed by 200 mg three times a week for 22 weeks. To compare regimens, patients were exactly matched on HIV and ART status, previous tuberculosis treatment history, and baseline acid-fast bacilli smear and culture result, while propensity score matched on age, sex, province of treatment, and isoniazid-susceptibility status. We did binomial linear regression to estimate adjusted risk differences (aRD) and 95% CIs for 24-month outcomes, which included: treatment success (ie, cure or treatment completion without evidence of recurrence) versus all other outcomes, survival versus death, disease free survival versus survival with treatment failure or recurrence, and loss to follow-up versus all other outcomes.Overall, 1387 (14%) of 10152 patients with rifampicin-resistant tuberculosis treated during 2017 met inclusion criteria; 688 in the bedaquiline group and 699 in the injectable group. Four patients (1%) had treatment failure or recurrence, 44 (6%) were lost to follow-up, and 162 (24%) died in the bedaquiline group, compared with 17 (2%), 87 (12%), and 199 (28%), respectively, in the injectable group. In adjusted analyses, treatment success was 14% (95% CI 8-20) higher in the bedaquiline group than in the injectable group (70% vs 57%); loss to follow-up was 4% (1-8) lower in the bedaquiline group (6% vs 12%); and disease-free survival was 2% (0-5) higher in the bedaquiline group (99% vs 97%). The bedaquiline group had 8% (4-11) lower risk of mortality during treatment (17·0% vs 22·4%), but there was no difference in mortality post-treatment.Patients in the bedaquiline group experienced significantly higher rates of treatment success at 24 months. This finding supports the use of short bedaquiline-containing regimens in eligible patients.WHO Global TB Programme.For the French translation of the abstract see Supplementary Materials section.

IntroductionThe Covid-19 pandemic is disrupting normal life globally. The COVID-19 pandemic is an emerging concern regarding the potential effects during breastfeeding. The aim of this study was to conduct a systemic review of mother-to -child transmission of COVID-19 during breastfeeding.MethodThis study systematically searched electronic databases; google scholar, PubMed, Medline, up December 2020. The study was included studies relevant to transmission breast milk and respiratory droplets during breastfeeding of mothers with COVID-19 positive. To identify the quality of data, prism standard was used and Strobe checklist scale.ResultA total of 3160 records were identified in this systemic review with eight relevant studies involving 159 mothers (63 mothers with COVID-19 positive, 55 of their breast milk samples tested negative for the-Covid-19. Twenty-one breast milk samples from 8 women tested positive for Covid-19. Of 73 infants were born to mothers with COVID-19 at the time of delivery. Two infants tested positive for Covid-19. The average mother-child separation time was 36•7 ± 21•1 days among mothers confirmed with COVID-19. Out of 22 mothers, ((37.5%) chose to breastfeed their babies after confirm covid-19 positive.ConclusionThis study shown that breastfeeding practices were extremely impacted during the COVID-19 epidemic among both confirmed positive cases and suspected mothers. However, the risk of mother-to-infant transmission of Covid-19 vertically or horizontally, in the perinatal period is very low.

Tuberculous meningitis (TBM) remains a major cause of morbidity and mortality in children with tuberculosis (TB), yet there are currently no estimates of the global burden of pediatric TBM. Due to frequent non-specific clinical presentation and limited and inadequate diagnostic tests, children with TBM are often diagnosed late or die undiagnosed. Even when diagnosed and treated, 20% of children with TBM die. Of survivors, the majority have substantial neurological disability with significant negative impact on children and their families. Surveillance data on this devastating form of TB can help to quantify the contribution of TBM to the overall burden, morbidity and mortality of TB in children and the epidemiology of TB more broadly. Pediatric TBM usually occurs shortly after primary infection with Mycobacterium tuberculosis and reflects ongoing TB transmission to children. In this article we explain the public health importance of pediatric TBM, discuss the epidemiology within the context of overall TB control and health system functioning and the limitations of current surveillance strategies. We provide a clear rationale for the benefit of improved surveillance of pediatric TBM using a TB care cascade framework to support monitoring and evaluation of pediatric TB, and TB control more broadly. Considering the public health implications of a diagnosis of TBM in children, we provide recommendations to strengthen pediatric TBM surveillance and outline how improved surveillance can help us identify opportunities for prevention, earlier diagnosis and improved care to minimize the impact of TBM on children globally.

Direct proton-knockout reactions of ^{55}Sc at ∼220 MeV/nucleon were studied at the RIKEN Radioactive Isotope Beam Factory. Populated states of ^{54}Ca were investigated through γ-ray and invariant-mass spectroscopy. Level energies were calculated from the nuclear shell model employing a phenomenological internucleon interaction. Theoretical cross sections to states were calculated from distorted-wave impulse approximation estimates multiplied by the shell model spectroscopic factors, which describe the wave function overlap of the ^{55}Sc ground state with states in ^{54}Ca. Despite the calculations showing a significant amplitude of excited neutron configurations in the ground-state of ^{55}Sc, valence proton removals populated predominantly the ground state of ^{54}Ca. This counterintuitive result is attributed to pairing effects leading to a dominance of the ground-state spectroscopic factor. Owing to the ubiquity of the pairing interaction, this argument should be generally applicable to direct knockout reactions from odd-even to even-even nuclei.

This article considers the relative advantages of alternative enterprise forms in finance from the point of view of public accountability. The business corporation is compared to the state agency or authority, the cooperative, the state corporation, and the charitable nonprofit. These forms can be distinguished according to whether they aspire to enhance general electoral democracy or stakeholder democracy and whether their democratic controls operate directly or indirectly. The article suggests that the indirect democratic forms may be more promising than the direct ones. It also argues that the project of democratizing finance depends on the development of practices of multifactor or “dialogic” performance assessment. Such practices must be institutionalized through public or private organizations that extend across firms.

Background: The American Thoracic Society, U.S. Centers for Disease Control and Prevention, European Respiratory Society, and Infectious Diseases Society of America jointly sponsored this new practice guideline on the treatment of drug-resistant tuberculosis (DR-TB). The document includes recommendations on the treatment of multidrug-resistant TB (MDR-TB) as well as isoniazid-resistant but rifampin-susceptible TB. Methods: Published systematic reviews, meta-analyses, and a new individual patient data meta-analysis from 12,030 patients, in 50 studies, across 25 countries with confirmed pulmonary rifampin-resistant TB were used for this guideline. Meta-analytic approaches included propensity score matching to reduce confounding. Each recommendation was discussed by an expert committee, screened for conflicts of interest, according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Results: Twenty-one Population, Intervention, Comparator, and Outcomes questions were addressed, generating 25 GRADE-based recommendations. Certainty in the evidence was judged to be very low, because the data came from observational studies with significant loss to follow-up and imbalance in background regimens between comparator groups. Good practices in the management of MDR-TB are described. On the basis of the evidence review, a clinical strategy tool for building a treatment regimen for MDR-TB is also provided. Conclusions: New recommendations are made for the choice and number of drugs in a regimen, the duration of intensive and continuation phases, and the role of injectable drugs for MDR-TB. On the basis of these recommendations, an effective all-oral regimen for MDR-TB can be assembled. Recommendations are also provided on the role of surgery in treatment of MDR-TB and for treatment of contacts exposed to MDR-TB and treatment of isoniazid-resistant TB.

The Lancet Respiratory Medicine Commission on drug-resistant tuberculosis was published in 2017, which comprehensively reviewed and provided recommendations on various aspects of the disease. Several key new developments regarding drug-resistant tuberculosis are outlined in this Commission Update. The WHO guidelines on treating drug-resistant tuberculosis were updated in 2019 with a reclassification of second line anti-tuberculosis drugs. An injection-free MDR tuberculosis treatment regimen is now recommended. Over the past 3 years, advances in treatment include the recognition of the safety and mortality benefit of bedaquiline, the finding that the 9-11 month injectable-based 'Bangladesh' regimen was non-inferior to longer regimens, and promising interim results of a novel 6 month 3-drug regimen (bedaquiline, pretomanid, and linezolid). Studies of explanted lungs from patients with drug-resistant tuberculosis have shown substantial drug-specific gradients across pulmonary cavities, suggesting that alternative dosing and drug delivery strategies are needed to reduce functional monotherapy at the site of disease. Several controversies are discussed including the optimal route of drug administration, optimal number of drugs constituting a regimen, selection of individual drugs for a regimen, duration of the regimen, and minimal desirable standards of antibiotic stewardship. Newer rapid nucleic acid amplification test platforms, including point-of-care systems that facilitate active case-finding, are discussed. The rapid diagnosis of resistance to other drugs, (notably fluoroquinolones), and detection of resistance by targeted or whole genome sequencing will probably change the diagnostic landscape in the near future.

Spatially dispersive nonlinear transmission lines (NLTLs) have attracted interest as pulsed RF sources. The characteristics of these sources need to be further evaluated and understood to optimize their design. This paper presents the performance of a spatially dispersive nickel-zinc (NiZn) NLTL for two experiments. The first experiment evaluated the RF power and frequency generated as a function of the primary dielectric medium for SF 6 compared to the previously implemented Royco 602 transformer oil. The second experiment evaluated the RF power and frequency generated as a function of the ferrites' loss tangents, initial permeabilities, and dimensions. The NLTL's performance is presented for each experiment across a range of operational input voltage levels and ferrite bias conditions. Experimental primary dielectric performance results demonstrate approximately 4X increase in RF power at frequencies above 1.2 GHz for replacement of oil with SF 6 . Experimental ferrite performance results show output frequencies from 0.9 to 1.39 GHz and peak RF powers >2X higher for the higher permeability and larger volume ferrite.

Children had better treatment outcomes and lower mortality rates than adults., Extensively drug-resistant tuberculosis (XDR TB) has extremely poor treatment outcomes in adults. Limited data are available for children. We report on clinical manifestations, treatment, and outcomes for 37 children (

Background Currently recommended treatment for multidrug-resistant (MDR) tuberculosis (TB) includes 4-8 months of an injectable medication, which is poorly tolerated. We evaluated the impact of coadministering lidocaine on pain and pharmacokinetics of intramuscular injections of amikacin in children with MDR-TB. Methods Children 8-18 years of age, receiving amikacin for MDR-TB treatment in Cape Town, South Africa, were eligible for this randomized crossover trial. Participants received a 15 mg/kg dose of intramuscular amikacin with and without additional lidocaine (0.2-0.4 mg/kg) on different days and were randomized to the order of the treatments (the sequence). Participants and staff completing evaluations were blinded to sequence. Samples were drawn predose, and at 1, 2, 4, 6 and 8 hours postdose for measurement of plasma amikacin concentrations. Pain was assessed by participants using the Wong Baker FACES pain scale (0-5) predose, immediately after the injection and then at 30 and 60 minutes. Pharmacokinetic measures were calculated using noncompartmental analysis. Results Twelve children were included, median age 11.5 years (interquartile range [IQR], 9.9-13.4 years). Participant-reported pain scores immediately after the amikacin injection were lower when lidocaine was coadministered: 1.0 (IQR, 0.5-2.0) with lidocaine versus 2.5 (1.0-4.0) without lidocaine (P = 0.004). The median area under the concentration time curve0-8 and median maximum plasma concentration of amikacin were 109.0 μg × h/mL (IQR, 84.7-121.3) and 36.7 μg/mL (IQR, 34.1-40.5) with lidocaine compared with 103.3 μg × h/mL (IQR, 81.7-135.0; P = 0.814) and 34.1 μg/mL (IQR, 35.6-46.4; P = 0.638) without lidocaine, respectively. Conclusions The coadministration of lidocaine resulted in reduced pain immediately after the injection and did not alter amikacin area under the concentration time curve or maximum plasma concentration.

BackgroundRifampicin doses of 40 mg/kg in adults are safe and well tolerated, may shorten anti-TB treatment and improve outcomes, but have not been evaluated in children.ObjectivesTo characterize the pharmacokinetics and safety of high rifampicin doses in children with drug-susceptible TB.Patients and methodsThe Opti-Rif trial enrolled dosing cohorts of 20 children aged 0–12 years, with incremental dose escalation with each subsequent cohort, until achievement of target exposures or safety concerns. Cohort 1 opened with a rifampicin dose of 15 mg/kg for 14 days, with a single higher dose (35 mg/kg) on day 15. Pharmacokinetic data from days 14 and 15 were analysed using population modelling and safety data reviewed. Incrementally increased rifampicin doses for the next cohort (days 1–14 and day 15) were simulated from the updated model, up to the dose expected to achieve the target exposure [235 mg/L·h, the geometric mean area under the concentration–time curve from 0 to 24 h (AUC0–24) among adults receiving a 35 mg/kg dose].ResultsSixty-two children were enrolled in three cohorts. The median age overall was 2.1 years (range = 0.4–11.7). Evaluated doses were ∼35 mg/kg (days 1–14) and ∼50 mg/kg (day 15) for cohort 2 and ∼60 mg/kg (days 1–14) and ∼75 mg/kg (day 15) for cohort 3. Approximately half of participants had an adverse event related to study rifampicin; none was grade 3 or higher. A 65–70 mg/kg rifampicin dose was needed in children to reach the target exposure.ConclusionsHigh rifampicin doses in children achieved target exposures and the doses evaluated were safe over 2 weeks.

A distributed optimal control problem for the 2D incompressible Navier–Stokes equation with delay in the convection term is studied. The delay corresponds to the non-instantaneous effect of the motion of a fluid parcel on the mass transfer, and can be realized as a regularization or stabilization to the Navier–Stokes equation. The existence of optimal controls is established, and the corresponding first-order necessary optimality system is determined. A semi-implicit discontinuous Galerkin scheme with respect to time and conforming finite elements for space is considered. Error analysis for this numerical scheme is discussed and optimal convergence rates are proved. The fully discrete problem is solved by the Barzilai-Borwein gradient method. Numerical examples for the velocity-tracking and vorticity minimization problems based on the Taylor-Hood elements are presented.

Phase change memory (PCM) is rapidly emerging as a promising candidate for building non-von Neumann accelerators for deep neural networks (DNN) based on in-memory computing. However, conductance drift and noise are key challenges for the reliable storage of synaptic weights in such accelerators. We demonstrate, for the first time, conductance drift and noise mitigation by integrating a projection liner into multilevel mushroom-type PCM devices. While the projection liner has little effect on SET-state drift (crystalline phase), it substantially reduces drift for RESET states (amorphous phase) and improves the overall noise across SET and RESET states. Further improvement in drift is demonstrated by combining projection liner with a low-drift GeSbTe (GST) phase-change material variant. Lower drift and lower device-to-device drift variability for devices with projection liner are confirmed with large-scale experiments of over 1,000 devices. Moreover, we demonstrate using 10,000 projected PCM devices that tighter closed-loop programming distributions can be achieved, which is critical for in-memory computing based accelerators for applications such as DNN inference. Simulations show that the lower drift and device-to-device drift variability significantly increase the inference life span of PCM-based DNN accelerators.

The tetraneutron has attracted the attention of nuclear physicists during the past decades, but there is still no unambiguous confirmation of its existence or non-existence. A new experiment based on $$^{8}$$ He(p, 2p) $$^{7}$$ H{t+ $$^{4}n$$ } reaction, with direct detection of the four neutrons, has been carried out at RIBF, which can hopefully help to draw a definite conclusion on the tetraneutron system.

We study classical dimers on two-dimensional quasiperiodic Ammann-Beenker (AB) tilings. Despite the lack of periodicity we prove that each infinite tiling admits 'perfect matchings' in which every vertex is touched by one dimer. We introduce an auxiliary 'AB$^*$' tiling obtained from the AB tiling by deleting all 8-fold coordinated vertices. The AB$^*$ tiling is again two-dimensional, infinite, and quasiperiodic. The AB$^*$ tiling has a single connected component, which admits perfect matchings. We find that in all perfect matchings, dimers on the AB$^*$ tiling lie along disjoint one-dimensional loops and ladders, separated by 'membranes', sets of edges where dimers are absent. As a result, the dimer partition function of the AB$^*$ tiling factorizes into the product of dimer partition functions along these structures. We compute the partition function and free energy per edge on the AB$^*$ tiling using an analytic transfer matrix approach. Returning to the AB tiling, we find that membranes in the AB$^*$ tiling become 'pseudomembranes', sets of edges which collectively host at most one dimer. This leads to a remarkable discrete scale-invariance in the matching problem. The structure suggests that the AB tiling should exhibit highly inhomogenous and slowly decaying connected dimer correlations. Using Monte Carlo simulations, we find evidence supporting this supposition in the form of connected dimer correlations consistent with power law behaviour. Within the set of perfect matchings we find quasiperiodic analogues to the staggered and columnar phases observed in periodic systems., 33 pages, 26 figures

We uncover topological features of neutral particle-hole pair excitations of correlated quantum anomalous Hall (QAH) insulators whose approximately flat conduction and valence bands have equal and opposite non-zero Chern number. Using an exactly solvable model we show that the underlying band topology affects both the center-of-mass and relative motion of particle-hole bound states. This leads to the formation of topological exciton bands whose features are robust to nonuniformity of both the dispersion and the Berry curvature. We apply these ideas to recently-reported broken-symmetry spontaneous QAH insulators in substrate aligned magic-angle twisted bilayer graphene., Comment: 5+10 pages, 2+2 figures; improved treatment of interaction effects, leading to |C|=1 excitons

We report a retrospective study on outcome of 14 newborn infants who received 62.5 times the recommended dose of Bacille Calmette-Guerin for immunization. All infants then received high-dose isoniazid and rifampicin (20 mg/kg/d each) as preventive therapy for 6 months. All had mild local adverse reactions, a third resolving within 16 weeks and all by 6 months.

Background: We compared outcomes up to 24 months after treatment initiation for rifampicin-resistant tuberculosis (RR-TB) patients in South Africa treated with a short, all-oral bedaquiline-containing regimen (bedaquiline group), or a short, injectable-containing regimen (injectable group). Methods: RR-TB patients eligible for a short regimen starting treatment between 1 January and 31 December 2017 with a bedaquiline-containing or WHO recommended injectable-containing treatment regimen of 9 to 12 months, registered with their national ID in the drug-resistant TB database and with known age, sex, and HIV status were eligible for study inclusion. To compare regimens, we exactly matched patients on HIV-infection, previous TB treatment history, baseline acid-fast bacilli smear and culture result, and propensity score matched patients on age, sex, and isoniazid susceptibility status, using logistic regression with generalized linear mixed models to estimate adjusted odds ratios (aOR) and 95% confidence intervals (95%CI). Results: Overall, 1,387 of the 10,152 RR-TB patients treated during 2017 met inclusion criteria, of whom 688 received the bedaquiline-containing regimen and 699 patients received the injectable-containing regimen. Four patients (0.6%) had treatment failure and/or recurrence, 44 (6.4%) were lost to follow-up, and 162 (23.5%) died in the bedaquiline group, compared to 17 (2.4%), 87 (12.4%), and 199 (28.5%), respectively, in the injectable group. Patients in the bedaquiline group had 1.8 (95%CI 1.4 to 2.4) times higher odds of treatment success at 24 months and 0.6 (0.4 to 0.8) times lower odds of loss to follow-up. This was consistent in stratified analyses on HIV-status, AFB smear positivity, and previous treatment history. The bedaquiline group had lower odds of mortality during treatment (0.5, 95%CI 0.4 to 0.7), but not post treatment (1.1, 95%CI 0.7 to 1.7). Conclusion: Patients in the bedaquiline group experienced significantly higher rates of treatment success at 24 months compared to the injectable group. The analysis supports the use of short bedaquiline-containing regimens in eligible patients. Funding: WHO Global TB Programme. Declaration of Interest: We declare no competing interests. Ethical Approval: This analysis was approved by Human Research Ethics Committee, Medical of University of Witwatersrand (#M150340, March 2015).