Massively parallel quantum computer simulator, eleven years later

A revised version of the massively parallel simulator of a universal quantum computer, described in this journal eleven years ago, is used to benchmark various gate-based quantum algorithms on some of the most powerful supercomputers that exist today. Adaptive encoding of the wave function reduces the memory requirement by a factor of eight, making it possible to simulate universal quantum computers with up to 48 qubits on the Sunway TaihuLight and on the K computer. The simulator exhibits close-to-ideal weak-scaling behavior on the Sunway TaihuLight,on the K computer, on an IBM Blue Gene/Q, and on Intel Xeon based clusters, implying that the combination of parallelization and hardware can track the exponential scaling due to the increasing number of qubits. Results of executing simple quantum circuits and Shor's factorization algorithm on quantum computers containing up to 48 qubits are presented.Comment: Substantially rewritten + new data. Published in Computer Physics Communicatio

Decoherence and Thermalization at Finite Temperatures for Quantum Systems

We consider a quantum system $S$ with Hamiltonian ${\cal H}_S$ coupled via a Hamiltonian ${\cal H}_{SE}$ to a quantum environment $E$ with Hamiltonian ${\cal H}_E$. We assume the entirety $S+E$ is in a canonical-thermal state at an inverse temperature $\beta$. The entirety is a closed quantum system which evolves via the time-dependent Schr{\”o}dinger equation with Hamiltonian ${\cal H}={\cal H}_S+{\cal H}_E+\lambda{\cal H}_{SE}$ where $\lambda$ is the overall strength of the system-environment coupling. Using both large-scale simulations and perturbation theory calculations in $\lambda$, we have studied a measure $\sigma(t)$ for decoherence and $\delta(t)$ for thermalization of $S$. We performed large-scale parallel calculations on spin systems with up to $N=40$ spins in the entirety, with both real-time and imaginary-time quantum calculations. We performed perturbation theory calculations about $\lambda=0$ and fluctuations about the average for the canonical-thermal ensemble, for both $\sigma$ and $\delta$. We obtained closed form expressions for both $\sigma$ and $\delta$, in terms of the free energies of $S$ and $E$. Our perturbation theory calculations agree very well with our numerical calculations, at least as long as $\beta\lambda$ is small

Screening and collective modes in disordered graphene antidot lattices

The excitation spectrum and the collective modes of graphene antidot lattices (GALs) are studied in the context of a $\pi$-band tight-binding model. The dynamical polarizability and dielectric function are calculated within the random phase approximation. The effect of different kinds of disorder, such as geometric and chemical disorder, are included in our calculations. We highlight the main differences of GALs with respect to single-layer graphene (SLG). Our results show that, in addition to the well-understood bulk plasmon in doped samples, inter-band plasmons appear in GALs. We further show that the static screening properties of undoped and doped GALs are quantitatively different from SLG.Comment: 12 pages; Replaced with published versio

Construction and Characterization of a Bacterial Artificial Chromosome Library for the Hexaploid Wheat Line 92R137

For map-based cloning of genes conferring important traits in the hexaploid wheat line 92R137, a bacterial artificial chromosome (BAC) library, including two sublibraries, was constructed using the genomic DNA of 92R137 digested with restriction enzymes HindIII and BamHI. The BAC library was composed of total 765,696 clones, of which 390,144 were from the HindIII digestion and 375,552 from the BamHI digestion. Through pulsed-field gel electrophoresis (PFGE) analysis of 453 clones randomly selected from the HindIII sublibrary and 573 clones from the BamHI sublibrary, the average insert sizes were estimated as 129 and 113 kb, respectively. Thus, the HindIII sublibrary was estimated to have a 3.01-fold coverage and the BamHI sublibrary a 2.53-fold coverage based on the estimated hexaploid wheat genome size of 16,700 Mb. The 765,696 clones were arrayed in 1,994 384-well plates. All clones were also arranged into plate pools and further arranged into 5-dimensional (5D) pools. The probability of identifying a clone corresponding to any wheat DNA sequence (such as gene Yr26 for stripe rust resistance) from the library was estimated to be more than 99.6%. Through polymerase chain reaction screening the 5D pools with Xwe173, a marker tightly linked to Yr26, six BAC clones were successfully obtained. These results demonstrate that the BAC library is a valuable genomic resource for positional cloning of Yr26 and other genes of interest

GRIK3 rs490647 is a Common Genetic Variant between Personality and Subjective Well-being in Chinese Han Population

Personality and subjective well-being (SWB) have been suggested to be strongly related in previous studies. This study was intended to confirm the relationship between personality and SWB and tried to seek out the genetic variants which underlie both personality and SWB. The subjects were 890 participants from Chinese Han population. We evaluated their personality using the Big Five Inventory (BFI) and used the Satisfaction With Life Scale (SWLS) to reflect their SWB. Five single nucleotide polymorphisms (SNPs) were selected from the literature (rs1426371, rs2164273, rs322931, rs3756290, rs490647) and genotyped for genetic association study. We found negative correlations between neuroticism and SWB. On the contrary, extraversion and agreeableness were positively associated with SWB. Three SNPs (rs2164273, rs3756290, rs490647) out of the five were found to connect with personality (extraversion, neuroticism, conscientiousness and openness to experience) and rs490647 variants of GRIK3 was also associated with SWB. Individuals carrying G allele at this site were predisposed to have lower risk to be neuroticism and greater chance to be extraverted, open and satisfied with their life. In summary, our study revealed that rs490647 might be a good candidate genetic variant for personality and SWB in Chinese Han population

Associations of psychological wellbeing with COVID-19 hospitalization and mortality in adults aged 50 years or older from 25 European countries and Israel

BackgroundLower psychological wellbeing is associated with poor outcomes in a variety of diseases and healthy populations. However, no study has investigated whether psychological wellbeing is associated with the outcomes of COVID-19. This study aimed to determine whether individuals with lower psychological wellbeing are more at risk for poor outcomes of COVID-19.MethodsData were from the Survey of Health, Aging, and Retirement in Europe (SHARE) in 2017 and SHARE's two COVID-19 surveys in June–September 2020 and June–August 2021. Psychological wellbeing was measured using the CASP-12 scale in 2017. The associations of the CASP-12 score with COVID-19 hospitalization and mortality were assessed using logistic models adjusted for age, sex, body mass index, smoking, physical activity, household income, education level, and chronic conditions. Sensitivity analyses were performed by imputing missing data or excluding cases whose diagnosis of COVID-19 was solely based on symptoms. A confirmatory analysis was conducted using data from the English Longitudinal Study of Aging (ELSA). Data analysis took place in October 2022.ResultsIn total, 3,886 individuals of 50 years of age or older with COVID-19 were included from 25 European countries and Israel, with 580 hospitalized (14.9%) and 100 deaths (2.6%). Compared with individuals in tertile 3 (highest) of the CASP-12 score, the adjusted odds ratios (ORs) of COVID-19 hospitalization were 1.81 (95% CI, 1.41–2.31) for those in tertile 1 (lowest) and 1.37 (95% CI, 1.07–1.75) for those in tertile 2. As for COVID-19 mortality, the adjusted ORs were 2.05 (95% CI, 1.12–3.77) for tertile 1 and 1.78 (95% CI, 0.98–3.23) for tertile 2, compared with tertile 3. The results were relatively robust to missing data or the exclusion of cases solely based on symptoms. This inverse association of the CASP-12 score with COVID-19 hospitalization risk was also observed in ELSA.ConclusionThis study shows that lower psychological wellbeing is independently associated with increased risks of COVID-19 hospitalization and mortality in European adults aged 50 years or older. Further study is needed to validate these associations in recent and future waves of the COVID-19 pandemic and other populations

Effect of allisartan on blood pressure and left ventricular hypertrophy through Kv1.5 channels in hypertensive rats

Background The objective of the present work was to study the anti-hypertensive effect of allisartan on blood pressure (BP) and in facilitating left ventricular remodeling through voltage-gated potassium channels (Kv) 1.5 channels. Methods A total of 30 SD rats were randomly divided into sham operation group, hypertension control group, and allisartan treatment group. Hypertension was induced by renal artery stenosis. The animals of treatment group were administered with allisartan once a day at a dose of 30 mg/kg body weight through an oral gavage for 4 weeks. The heart function of animals post 4 weeks of treatment was evaluated by echocardiography, and the degree of ventricular hypertrophy and cardiomyocyte hypertrophy were evaluated by histomorphology. The expression of Kv1.5 is detected by real-time quantitative polymerase chain reaction while Western blotting was used to detect the protein expression. Results Four weeks after renal artery stenosis, a significant difference was observed in the whole heart ratio, left heart ratio, and cardiomyocyte area between allisartan treatment group and the hypertension control group (P< .01). A significant decrease in BP of allisartan treatment group compared to hypertension control group (P< .01) was observed. The expression of Kv1.5 mRNA was increased significantly (P< .01) in allisartan treatment group compared to hypertension control group. Western blot analysis also confirmed the increased expression of Kv1.5 channel. Conclusion The results showed that allisartan lowers BP and improves left ventricular remodeling through increased expression of Kv1.5 mRNA

Parallel, Large-Scale, and Long Synthetic Oligodeoxynucleotide Purification Using the Catching Full-Length Sequence by Polymerization Technique

© 2018 American Chemical Society. The catching by polymerization synthetic oligodeoxynucleotide (ODN) purification technique was shown to be potentially suitable for high-throughput purification by the purification of 12 ODNs simultaneously, to be convenient for large-scale purification by purification at the 60 μmol synthesis scale, and to be highly powerful for purification of long ODNs by purification of ODNs as long as 303-mers. LC-MS analysis indicated that the ODNs purified with the technique have excellent purity

Approach to Equilibrium in Nano-scale Systems at Finite Temperature

We study the time evolution of the reduced density matrix of a system of spin-1/2 particles interacting with an environment of spin-1/2 particles. The initial state of the composite system is taken to be a product state of a pure state of the system and a pure state of the environment. The latter pure state is prepared such that it represents the environment at a given finite temperature in the canonical ensemble. The state of the composite system evolves according to the time-dependent Schrödinger equation, the interaction creating entanglement between the system and the environment. It is shown that independent of the strength of the interaction and the initial temperature of the environment, all the eigenvalues of the reduced density matrix converge to their stationary values, implying that also the entropy of the system relaxes to a stationary value. We demonstrate that the difference between the canonical density matrix and the reduced density matrix in the stationary state increases as the initial temperature of the environment decreases. As our numerical simulations are necessarily restricted to a modest number of spin-1/2 particles (<36), but do not rely on time-averaging of observables nor on the assumption that the coupling between system and environment is weak, they suggest that the stationary state of the system directly follows from the time evolution of a pure state of the composite system, even if the size of the latter cannot be regarded as being close to the thermodynamic limit.