We report a quantum simulation of the deuteron binding energy on quantum processors accessed via cloud servers. We use a Hamiltonian from pionless effective field theory at leading order. We design a ...low-depth version of the unitary coupled-cluster ansatz, use the variational quantum eigensolver algorithm, and compute the binding energy to within a few percent. Our work is the first step towards scalable nuclear structure computations on a quantum processor via the cloud, and it sheds light on how to map scientific computing applications onto nascent quantum devices.
We present a quantum-classical algorithm to study the dynamics of the two-spatial-site Schwinger model on IBM's quantum computers. Using rotational symmetries, total charge, and parity, the number of ...qubits needed to perform computation is reduced by a factor of ~5, removing exponentially large unphysical sectors from the Hilbert space. Our work opens an avenue for exploration of other lattice quantum field theories, such as quantum chromodynamics, where classical computation is used to find symmetry sectors in which the quantum computer evaluates the dynamics of quantum fluctuations.
Toxoplasmosis (TXP) is a life-threatening complication of allogeneic haematopoietic stem cell transplantation (AHSCT). Little is known about the risk factors and there is no consensus on prophylactic ...measures. To investigate the risk factors, we conducted a single-centre, retrospective matched case–control study among adults who underwent AHSCT from January 2006 to March 2015 in our hospital. TXP cases were identified from the prospectively maintained hospital's database. The 1:2 control population consisted of the two patients who received an AHSCT immediately before and after each case with similar donor relationship (related, unrelated) but who did not develop TXP. Risk factors were identified by conditional logistic regression. Clinical features and outcome of TXP were examined. Twenty-three (3.9%) cases of TXP (20 diseases, three infections) were identified among 588 AHSCT recipients. Twenty (87%) cases had a positive pre-transplant Toxoplasma gondii serology. In comparison with 46 matched control patients, risk factors were the absence of effective anti-Toxoplasma prophylaxis (odds ratio (OR) 11.95; 95% CI 3.04–46.88; p <0.001), high-grade (III–IV) acute graft-versus-host-disease (OR 3.1; 95% CI 1.04–9.23; p 0.042) and receipt of the tumour necrosis factor-α blocker etanercept (OR 12.02; 95% CI 1.33–108.6; p 0.027). Mortality attributable to TXP was 43.5% (n = 10). Non-relapse mortality rates during the study period of cases and controls were 69.6% (n = 16) and 17.4% (n = 8), respectively. Lung involvement was the dominant clinical feature (n = 14). Two cases were associated with graft failure, one preceded by haemophagocytic syndrome. Given TXP-related morbidity and attributable mortality, anti-Toxoplasma prophylaxis is essential for optimized management of seropositive AHSCT recipients.
Heterogeneous high-performance computing (HPC) systems offer novel architectures which accelerate specific workloads through judicious use of specialized coprocessors. A promising architectural ...approach for future scientific computations is provided by heterogeneous HPC systems integrating quantum processing units (QPUs). To this end, we present XACC (eX treme-scale ACC elerator) — a programming model and software framework that enables quantum acceleration within standard or HPC software workflows. XACC follows a coprocessor machine model that is independent of the underlying quantum computing hardware, thereby enabling quantum programs to be defined and executed on a variety of QPUs types through a unified application programming interface. Moreover, XACC defines a polymorphic low-level intermediate representation, and an extensible compiler frontend that enables language independent quantum programming, thus promoting integration and interoperability across the quantum programming landscape. In this work we define the software architecture enabling our hardware and language independent approach, and demonstrate its usefulness across a range of quantum computing models through illustrative examples involving the compilation and execution of gate and annealing-based quantum programs.
Actinomycosis is a rare chronic and multifaceted disease caused by Actinomyces species frequently mimicking malignancy or other chronic granulomatous lung diseases. We report 4 original presentations ...of actinomycosis arising under supposed penicillin prophylaxis in allogeneic stem cell transplantation recipients.
Alzheimer's disease (AD) is highly heritable and recent studies have identified over 20 disease-associated genomic loci. Yet these only explain a small proportion of the genetic variance, indicating ...that undiscovered loci remain. Here, we performed a large genome-wide association study of clinically diagnosed AD and AD-by-proxy (71,880 cases, 383,378 controls). AD-by-proxy, based on parental diagnoses, showed strong genetic correlation with AD (r
= 0.81). Meta-analysis identified 29 risk loci, implicating 215 potential causative genes. Associated genes are strongly expressed in immune-related tissues and cell types (spleen, liver, and microglia). Gene-set analyses indicate biological mechanisms involved in lipid-related processes and degradation of amyloid precursor proteins. We show strong genetic correlations with multiple health-related outcomes, and Mendelian randomization results suggest a protective effect of cognitive ability on AD risk. These results are a step forward in identifying the genetic factors that contribute to AD risk and add novel insights into the neurobiology of AD.
Abstract Plasma ignition can significantly improve the efficiency and performance of combustion devices through the enhancement of combustibility limits. Investigating plasma development for ...fundamental experimental flame conditions (i.e. spherical flame experiments) can provide insight into how plasma thermalizes the combustible mixture and, therefore a better understanding of flame development in future experimental studies. This study observed an ignition system designed to produce spherical flames in quiescent gas inside a constant-volume combustion chamber. Rotational and vibrational temperature measurements of dry atmospheric air glow plasma are reported. Measurements were taken for a transient discharge with currents less than 0.5 A. The electrode wire geometry and discharge variation resulted in an ellipsoid-shaped kernel and plasma region with an abnormal glow discharge. The measured temperatures were compared to the conductive thermal kernel boundary observed with Schlieren imaging. Maximum rotational and vibrational temperatures of 3000 K and 10 000 K, respectively, were observed near the anode electrode for a 0.5 A current. The temperature decreased with the axial distance from the anode, while a constant temperature was observed in the radial direction. Lower currents resulted in a smaller temperature, with minimum measured rotational and vibrational temperatures of 1500 K and 5000 K, respectively. The results were compared with available experimental literature and the variation observed was a result of the transient nature, which resulted in hysteresis in temperature vs discharge current measurements.
Context:
Monocarboxylate transporter 8 (MCT8) is a thyroid hormone-specific cell membrane transporter. MCT8 deficiency causes severe psychomotor retardation and abnormal thyroid tests. The great ...majority of affected children cannot walk or talk, and all have elevated serum T3 levels, causing peripheral tissue hypermetabolism and inability to maintain weight. Treatment with thyroid hormone is ineffective. In Mct8-deficient mice, the thyroid hormone analog, diiodothyropropionic acid (DITPA), does not require MCT8 to enter tissues and could be an effective alternative to thyroid hormone treatment in humans.
Objective:
The objective of the study was to evaluate the effect and efficacy of DITPA in children with MCT8 deficiency.
Methods:
This was a multicenter report of four affected children given DITPA on compassionate grounds for 26–40 months. Treatment was initiated at ages 8.5–25 months, beginning with a small dose of 1.8 mg, increasing to a maximal 30 mg/d (2.1–2.4 mg/kg · d), given in three divided doses.
Results:
DITPA normalized the elevated serum T3 and TSH when the dose reached 1 mg/kg · d and T4 and rT3 increased to the lower normal range. The following significant changes were also observed: decline in SHBG (in all subjects), heart rate (in three of four), and ferritin (in one of four). Cholesterol increased in two subjects. There was no weight loss and weight gain occurred in two. None of the treated children required a gastric feeding tube or developed seizures. No adverse effects were observed.
Conclusion:
DITPA (1–2 mg/kg · d) almost completely normalizes thyroid tests and reduces the hypermetabolism and the tendency for weight loss. The effects of earlier commencement and long-term therapy remain to be determined.
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