Massive Parallel Quantum Computer Simulator

We describe portable software to simulate universal quantum computers on massive parallel computers. We illustrate the use of the simulation software by running various quantum algorithms on different computer architectures, such as a IBM BlueGene/L, a IBM Regatta p690+, a Hitachi SR11000/J1, a Cray X1E, a SGI Altix 3700 and clusters of PCs running Windows XP. We study the performance of the software by simulating quantum computers containing up to 36 qubits, using up to 4096 processors and up to 1 TB of memory. Our results demonstrate that the simulator exhibits nearly ideal scaling as a function of the number of processors and suggest that the simulation software described in this paper may also serve as benchmark for testing high-end parallel computers.Comment: To appear in Comp. Phys. Com

Fate of Quasiparticle at Mott Transition and Interplay with Lifshitz Transition Studied by Correlator Projection Method

Filling-control metal-insulator transition on the two-dimensional Hubbard model is investigated by using the correlator projection method, which takes into account momentum dependence of the free energy beyond the dynamical mean-field theory. The phase diagram of metals and Mott insulators is analyzed. Lifshitz transitions occur simultaneously with metal-insulator transitions at large Coulomb repulsion. On the other hand, they are separated each other for lower Coulomb repulsion, where the phase sandwiched by the Lifshitz and metal-insulator transitions appears to show violation of the Luttinger sum rule. Through the metal-insulator transition, quasiparticles retain nonzero renormalization factor and finite quasi-particle weight in the both sides of the transition. This supports that the metal-insulator transition is caused not by the vanishing renormalization factor but by the relative shift of the Fermi level into the Mott gap away from the quasiparticle band, in sharp contrast with the original dynamical mean-field theory. Charge compressibility diverges at the critical end point of the first-order Lifshitz transition at finite temperatures. The origin of the divergence is ascribed to singular momentum dependence of the quasiparticle dispersion.Comment: 24 pages including 10 figure

Retrospective chart review of oral somatic delusions

Objective: Oral cenesthopathy is characterized by foreign body sensations without medical and dental evidence for them. It is thought to be a rare disease in psychiatry, but many patients are visiting dental clinics seeking treatment to remove a foreign body. Even though the features of oral cenesthopathy might be different between a psychiatric clinic and a dental clinic, there has been no clinico-statistical study from dentists. In this study, we report a clinico-statistical study of patients with oral cenesthopathy in dentistry. Methods: This is a retrospective chart review of 606 outpatients with oral cenesthopathy in Tokyo Medical and Dental University from April 2010 through to March 2015. Results: A total of 159 male and 447 female patients were included in this study. The mean age was 62.08 years, and female patients were older than male patients. The trigger of the dental treatment and the acute phase of depression at the onset were significantly related (p=0.037). Only 128 patients (36%) had clinically significant improvement after 6 months of pharmacotherapy. No history of psychiatric disorders (odds ratio [OR] 0.479 [95% confidence interval {CI}: 0.262–0.875], p=0.017) and longer duration of illness (>18 months) (OR 2.626 [95% CI: 1.437–4.799], p=0.002) were significant factors for clinical outcomes. Conclusion: Patients with oral cenesthopathy in our clinic were predominantly elderly female patients. Dental treatment in the acute phase of depression might be a risk factor for oral cenesthopathy. Therefore, comprehending the situation of psychiatric disorder and obtaining adequate informed consent might be required to prevent the trouble concerning oral cenesthopathy

Pharmacotherapeutic outcomes in atypical odontalgia : determinants of pain relief

Objectives: There has been considerable research which has focused on clarifying the origin of pain in patients with atypical odontalgia (AO), also known as “idiopathic toothache”, and on identifying effective treatment, but there has been limited success so far. In this study, we assessed the outcomes of treatment and attempted to identify factors that could account for pain remission in patients with AO. Patients and methods: Data for 165 patients diagnosed with AO from June 2015 to August 2017 were retrospectively reviewed. The patients’ sex, age, duration of pain, and psychiatric history were collected, along with information on pain intensity, depressive status, and catastrophizing scores. Responses at 4 and 16 weeks from the start of treatment were observed. The associations between potentially associated factors and outcome were investigated using Bayesian model averaging. Results: A 30% reduction in pain was reported by 38 patients (46.3%) at 4 weeks and by 54 patients (65.9%) at 16 weeks. The pain intensity decreased as the depression and catastrophizing score improved; all of the changes were statistically significant (P<0.001). Four elements, that is, patient sex, depression score at baseline, pain score at 4 weeks, and change in the catastrophizing score, explained 52.5% of the variation in final outcome between individual patients. Conclusion: Our findings confirm the efficacy of tricyclic antidepressants (TCAs) as a treatment for AO and indicate that other medications, especially aripiprazole used in combination with a TCA, may be useful. A considerable number of patients, especially women, those with lower levels of depression at baseline, and those who responded to 4 weeks of treatment, achieved pain relief

X-ray photoemission study of NiS_{2-x}Se_x (x = 0.0 - 1.2)

Electronic structure of NiS_{2-x}Se_x system has been investigated for various compositions (x) using x-ray photoemission spectroscopy. An analysis of the core level as well as the valence band spectra of NiS_2 in conjunction with many-body cluster calculations provides a quantitative description of the electronic structure of this compound. With increasing Se content, the on-site Coulomb correlation strength (U) does not change, while the band width W of the system increases, driving the system from a covalent insulating state to a pd-metallic state.Comment: 19 pages, 6 figures, To appear in Phys. Rev. B, 200

Helicity-Flip Off-Foward Parton Distributions of the Nucleon

We identify quark and gluon helicity-flip distributions defined between nucleon states of unequal momenta. The evolution of these distributions with change of renormalization scale is calculated in the leading-logarithmic approximation. The helicity-flip gluon distributions do not mix with any quark distribution and are thus a unique signature of gluons in the nucleon. Their contribution to the generalized virtual Compton process is obtained both in the form of a factorization theorem and an operator product expansion. In deeply virtual Compton scattering, they can be probed through distinct angular dependence of the cross section.Comment: a few corrections made, references change

In-Situ Nuclear Magnetic Resonance Investigation of Strain, Temperature, and Strain-Rate Variations of Deformation-Induced Vacancy Concentration in Aluminum

Critical strain to serrated flow in solid solution alloys exhibiting dynamic strain aging (DSA) or Portevin–LeChatelier effect is due to the strain-induced vacancy production. Nuclear magnetic resonance (NMR) techniques can be used to monitor in situ the dynamical behavior of point and line defects in materials during deformation, and these techniques are nondestructive and noninvasive. The new CUT-sequence pulse method allowed an accurate evaluation of the strain-enhanced vacancy diffusion and, thus, the excess vacancy concentration during deformation as a function of strain, strain rate, and temperature. Due to skin effect problems in metals at high frequencies, thin foils of Al were used and experimental results correlated with models based on vacancy production through mechanical work (vs thermal jogs), while in situ annealing of excess vacancies is noted at high temperatures. These correlations made it feasible to obtain explicit dependencies of the strain-induced vacancy concentration on test variables such as the strain, strain rate, and temperature. These studies clearly reveal the power and utility of these NMR techniques in the determination of deformation-induced vacancies in situ in a noninvasive fashion.

Limited Tumor Tissue Drug Penetration Contributes to Primary Resistance against Angiogenesis Inhibitors

Resistance mechanisms against antiangiogenic drugs are unclear. Here, we correlated the antitumor and antivascular properties of five different antiangiogenic receptor tyrosine kinase inhibitors (RTKIs) (motesanib, pazopanib, sorafenib, sunitinib, vatalanib) with their intratumoral distribution data obtained by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI). In the first mouse model, only sunitinib exhibited broad-spectrum antivascular and antitumor activities by simultaneously suppressing vascular endothelial growth factor receptor-2 (VEGFR2) and desmin expression, and by increasing intratumoral hypoxia and inhibiting both tumor growth and vascularisation significantly. Importantly, the highest and most homogeneous intratumoral drug concentrations have been found in sunitinib-treated animals. In another animal model, where - in contrast to the first model - vatalanib was detectable at homogeneously high intratumoral concentrations, the drug significantly reduced tumor growth and angiogenesis. In conclusion, the tumor tissue penetration and thus the antiangiogenic and antitumor potential of antiangiogenic RTKIs vary among the tumor models and our study demonstrates the potential of MALDI-MSI to predict the efficacy of unlabelled small molecule antiangiogenic drugs in malignant tissue. Our approach is thus a major technical and preclinical advance demonstrating that primary resistance to angiogenesis inhibitors involves limited tumor tissue drug penetration. We also conclude that MALDI-MSI may significantly contribute to the improvement of antivascular cancer therapies

Overexpression of Mcl-1 exacerbates lymphocyte accumulation and autoimmune kidney disease in lpr mice

Cell death by apoptosis has a critical role during embryonic development and in maintaining tissue homeostasis. In mammals, there are two converging apoptosis pathways: the ‘extrinsic’ pathway, which is triggered by engagement of cell surface ‘death receptors’ such as Fas/APO-1; and the ‘intrinsic’ pathway, which is triggered by diverse cellular stresses, and is regulated by prosurvival and pro-apoptotic members of the Bcl-2 family of proteins. Pro-survival Mcl-1, which can block activation of the proapoptotic proteins, Bax and Bak, appears critical for the survival and maintenance of multiple haemopoietic cell types. To investigate the impact on haemopoiesis of simultaneously inhibiting both apoptosis pathways, we introduced the vavP-Mcl-1 transgene, which causes overexpression of Mcl-1 protein in all haemopoietic lineages, into Faslpr/lpr mice, which lack functional Fas and are prone to autoimmunity. The combined mutations had a modest impact on myelopoiesis, primarily an increase in the macrophage/monocyte population in Mcl-1tg/lpr mice compared with lpr or Mcl-1tg mice. The impact on lymphopoiesis was striking, with a marked elevation in all major lymphoid subsets, including the non-conventional double-negative (DN) T cells (TCRβ+ CD4– CD8– B220+ ) characteristic of Faslpr/lpr mice. Of note, the onset of autoimmunity was markedly accelerated in Mcl-1tg/lpr mice compared with lpr mice, and this was preceded by an increase in immunoglobulin (Ig)-producing cells and circulating autoantibodies. This degree of impact was surprising, given the relatively mild phenotype conferred by the vavP-Mcl-1 transgene by itself: a two- to threefold elevation of peripheral B and T cells, no significant increase in the non-conventional DN T-cell population and no autoimmune disease. Comparison of the phenotype with that of other susceptible mice suggests that the development of autoimmune disease in Mcl-1tg/lpr mice may be influenced not only by Ig-producing cells but also other haemopoietic cell types