Charge-Ordered State versus Dimer-Mott Insulator at Finite Temperatures

We theoretically investigate the competition between charge-ordered state and Mott insulating state at finite temperatures in quarter-filled quasi-one-dimensional electron systems, by studying dimerized extended Hubbard chains with interchain Coulomb interactions. In order to take into account one-dimensional fluctuations properly, we apply the bosonization method to an effective model obtained by the interchain mean-field approximation. The results show that lattice dimerization, especially in the critical region, and frustration in the interchain Coulomb interactions reduce the charge-ordering phase transition temperature and enlarge the dimer-Mott insulating phase. We also derive a general formula of the Knight shift in the charge-ordered phase and its implication to experiments is discussed.Comment: 5 pages, 4 figures, to be published in J. Phys. Soc. Jpn. Vol.76 No.1

Reliability Quantification of Deep Reinforcement Learning-based Control

Reliability quantification of deep reinforcement learning (DRL)-based control is a significant challenge for the practical application of artificial intelligence (AI) in safety-critical systems. This study proposes a method for quantifying the reliability of DRL-based control. First, an existing method, random noise distillation, was applied to the reliability evaluation to clarify the issues to be solved. Second, a novel method for reliability quantification was proposed to solve these issues. The reliability is quantified using two neural networks: reference and evaluator. They have the same structure with the same initial parameters. The outputs of the two networks were the same before training. During training, the evaluator network parameters were updated to maximize the difference between the reference and evaluator networks for trained data. Thus, the reliability of the DRL-based control for a state can be evaluated based on the difference in output between the two networks. The proposed method was applied to DQN-based control as an example of a simple task, and its effectiveness was demonstrated. Finally, the proposed method was applied to the problem of switching trained models depending on the state. Con-sequently, the performance of the DRL-based control was improved by switching the trained models according to their reliability.Comment: 18 pages and 17 figure

Hidden particle production at the ILC

In a class of new physics models, new physics sector is completely or partly hidden, namely, singlet under the Standard Model (SM) gauge group. Hidden fields included in such new physics models communicate with the Standard Model sector through higher dimensional operators. If a cutoff lies in the TeV range, such hidden fields can be produced at future colliders. We consider a scalar filed as an example of the hidden fields. Collider phenomenology on this hidden scalar is similar to that of the SM Higgs boson, but there are several features quite different from those of the Higgs boson. We investigate productions of the hidden scalar at the International Linear Collider (ILC) and study the feasibility of its measurements, in particular, how well the ILC distinguishes the scalar from the Higgs boson, through realistic Monte Carlo simulations.Comment: the version to be published in PR

Increased fructose 2,6-bisphosphate in peripheral blood mononuclear cells of patients with diabetes

Fructose 2,6-bisphosphate (F2,6BP) is a powerful allosteric activator of 6-phosphofructo-1-kinase, which is the rate-limiting enzyme for glycolysis. Mitogenic stimulation of lymphocytes is related to an enhanced rate of glucose utilization and F2,6BP mediated activation of glycolysis. To determine the effect of hyperglycemia on intracellular glycolysis of lymphocytes, we measured intracellular F2,6BP content in peripheral blood mononuclear cells obtained from patients with diabetes and normal subjects. A total of 62 subjects participated in the present study. Venous blood samples were collected and peripheral blood mononuclear cells were separated by Ficoll gradients. Intracellular F2,6BP levels in peripheral blood mononuclear cells from normal control subjects were significantly lower than age-matched diabetic subjects. We observed a significant positive correlation between intracellular F2,6BP levels and long term glycemic control, as assessed by HbA1c. These data suggest that hyperglycemia increases intracellular F2,6BP in immune cells. These findings may help to clarify the impaired function in immune cells in patients with diabetes

Wideband phase-locked loop circuit with real-time phase correction for frequency modulation atomic force microscopy

We have developed a wideband phase-locked loop (PLL) circuit with real-time phase correction for high-speed and accurate force measurements by frequency modulation atomic force microscopy (FM-AFM) in liquid. A high-speed operation of FM-AFM requires the use of a high frequency cantilever which, however, increases frequency-dependent phase delay caused by the signal delay within the cantilever excitation loop. Such phase delay leads to an error in the force measurements by FM-AFM especially with a low Q factor. Here, we present a method to compensate this phase delay in real time. Combined with a wideband PLL using a subtraction-based phase comparator, the method allows to perform an accurate and high-speed force measurement by FM-AFM. We demonstrate the improved performance by applying the developed PLL to three-dimensional force measurements at a mica/water interface. © 2011 American Institute of Physics

Theobromine suppresses adipogenesis through enhancement of CCAAT-enhancer-binding protein beta degradation by adenosine receptor A1

Theobromine, a methylxanthine derived from cacao beans, reportedly has various health-promoting properties but molecular mechanism by which effects of theobromine on adipocyte differentiation and adipogenesis remains unclear. In this study, we aimed to clarify the molecular mechanisms of the anti-adipogenic effect of theobromine in vitro and in vivo. ICR mice (4 week-old) were administered with theobromine (0.1 g/kg) for 7 days. Theobromine administration attenuated gains in body and epididymal adipose tissue weights in mice and suppressed expression of adipogenic-associated genes in mouse adipose tissue. In 3T3-L1 preadipocytes, theobromine caused degradation of C/EBP beta protein by the ubiquitin-proteasome pathway. Pull down assay showed that theobromine selectively interacts with adenosine receptor A1(AR1), and AR1 knockdown inhibited theobromine-induced C/ESPfi degradation. Theobromine increased sumoylation of C/EBP beta' at Lys133. Expression of the small ubiquitin-like modifier (SUMO)-specific protease 2 (SENP2) gene, coding for a desumoylation enzyme, was suppressed by theobromine. In vivo knockdown studies showed that AR1 knockdown in mice attenuated the anti-adipogenic effects of theobromine in younger mice. Theobromine suppresses adipocyte differentiation and induced C/EBPP degradation by increasing its sumoylation. Furthermore, the inhibition of AR1 signaling is important for theobromine-induced C/EBP beta degradation.ArticleBIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH.1864(12):2438-2448(2017)journal articl

A case of intramandibular neurofibroma resembling a radicular cyst in a neurofibromatosis type 1 patient

INTRODUCTION: Neurofibromatosis is a disease that causes various abnormalities such as neurofibroma, mainly in the skin and nerves. The common sites in the oral cavity are the palate, gingiva, tongue, buccal mucosa, and lips but, occurrence in the mandible is rare. PRESENTATION OF CASE: A 26-year-old woman was referred to our clinic because of percussion pain. Radiographic findings showed a radiolucent area. The patient was clinically diagnosed with a radicular cyst by a previous doctor. Multiple cafe-au-lait spots were found disseminated on her body, and she had already been prenatally diagnosed with neurofibromatosis type 1 (NF1). We performed a biopsy and suggested a neurofibroma. Tumor extirpation was performed under general anesthesia. The histopathological diagnosis showed a neurofibroma. CLINICAL DISCUSSION AND CONCLUSION: NF1 is a systemic nevus that causes abnormalities in melanocytes and Schwann cells, and various lesions appear, but intramandibular lesions are extremely rare. Diagnosis of NF1 and radicular cysts in the mandible is difficult due to their image resemblance. However, it should be kept in mind if the underlying disease is NF1. In our case, it was easy to detach and may have originated from small peripheral nerve endings in the mandible