中国における種類株式の研究――日本、アメリカ、台湾を比較対象として

東洋大学202

Auslander-Reiten theory in triangulated categories

In this dissertation, let B be a triangulated category and let D be an extension-closed subcategory of B. First, we give some new characterizations of an Auslander-Reiten triangle in D, which yields some necessary and sufficient conditions for D to have Auslander-Reiten triangles. Next, we study when an Auslander-Reiten triangle in B induces an Auslander-Reiten triangle in D. As an application, we study Auslander-Reiten triangles in a triangulated category with a t-structure. In case the t-structure has a t-hereditary heart, we establish the connection between the Auslander-Reiten triangles in B and the Auslander-Reiten sequences in the heart. Finally, we specialize to the bounded derived category of all modules of a noetherian algebra over a complete local noetherian commutative ring. Our result generalizes the corresponding result of Happel’s in the bounded derived category of finite dimensional modules of a finite dimensional algebra over an algebraically closed field

Long-time nonlinear dynamical evolution for P-band ultracold atoms in an optical lattice

We report the long-time nonlinear dynamical evolution of ultracold atomic gases in the P-band of an optical lattice. A Bose-Einstein condensate (BEC) is fast and efficiently loaded into the Pband at zero quasi-momentum with a non-adiabatic shortcut method. For the first one and half milliseconds, these momentum states undergo oscillations due to coherent superposition of different bands, which are followed by oscillations up to 60ms of a much longer period. Our analysis shows the dephasing from the nonlinear interaction is very conducive to the long-period oscillations induced by the variable force due to the harmonic confinement.Comment: 8 pages, 7 figure

Combination of microporous hollow carbon spheres and nafion for the individual metal-free stripping detectionof Pb2+ and Cd2+

Here, the combination of Nafion with microporous hollow carbon spheres (MHCS) is first proposed to fabricate a disposable metal-free electrode for heavy metal stripping sensing. The MHCS-Nafion composite film electrode is prepared by drop-casting a mixture of MHCS and Nafion onto the lab-made screen-printed carbon electrode (SPCE*). Results demonstrate that the interfusion of MHCS into Nafion offers enhanced performance for the electro-enrichment and stripping of lead and cadmium over the only Nafion film: 1) abundant MHCS immobilized on the electrode surface serve as effective nucleation sites for metal ion reduction; 2) the mixing of MHCS into Nafion enlarges the active surface of negative-charged Nafion for the electrostatic adsorption of metal cations. The proposed MHCS-Nafion/SPCE* provides linear responses for Pb2+ and Cd2+ in the range of 2 - 200 mu g/L, with a detection limit of 1.37 and 1.63 mu g/L, respectively. Practical applications of the sensor in water sample detection with good accuracy have also been confirmed

Ameliorative effect of protein and calcium on fluoride-induced hepatotoxicity in rabbits

To investigate whether protein (Pr) or calcium (Ca) supplementation could ameliorate hepatic damage induced by excessive fluoride (F); thirty-two 30-day-old healthy New Zealand rabbits were randomly divided into four groups (female: male = 1:1). The four groups were maintained on distilled water and fed the following diets for 120 days: (1) a malnutrition control (MC) diet (8.58% Pr, 0.49% Ca); (2) the MC diet plus HiF (high fluoride in their diet, 200 mg F ion/kg from NaF); (3) a Ca deficient MC diet plus HiPr+HiF (0.46% Ca, 18.41% Pr, plus HiF); and (4) a Pr deficient MC diet plus HiCa+HiF (2.23% Ca, 8.35% Pr, plus HiF). Results show that in HiF group, the serum total Pr (TPr) and albumin (ALB) content significantly decreased, whereas both Pr and Ca rich diets significantly enhanced their levels. In liver, low superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, high malondialdehyde (MDA) content, and evident mitochondria lesions in HiF group indicated a significant oxidative stress, while Pr or Ca supplementation brought an ultrastructural repair and a recovery antioxidant defense in liver. The findings in the present work implied the ameliorative effects of Pr or Ca supplementation on F-induced hepatotoxicity in rabbits.Keywords: Fluoride, hepatotoxicity, malnutrition, calcium supplementation, protein supplementatio

A Novel Uni-Acupoint Electroacupuncture Stimulation Method for Pain Relief

Electroacupuncture stimulation (EAS) has been demonstrated effective for pain relief and treating other various diseases. However, the conventional way of EAS, the bi-acupoint method, is not suitable for basis study of acupoint specificity. Moreover, its operations are inconvenient and difficult to be persevered, especially for long-term, continuous and even imperative treatments. These disadvantages motivate designs of new EAS methods. We present a novel uni-acupoint electrical stimulation method, which is applied at a single acupoint and quite meets the needs of basis study and simpler clinical application. Its pain relief effect has been evaluated by animal tests of Wistar rats. During the experiments, rats were given 30 min 2/100 Hz uni- and bi-acupoint EAS and their nociceptive thresholds before and after EAS were attained by hot-plate test. The analgesic effect was defined as the change of nociceptive threshold and used to evaluate the effectiveness of uni-acupoint EAS for pain relief. The hot-plate test results indicated that analgesic effect of uni-acupoint group was significantly higher than that of the control group and there was no significant difference of analgesic effects between uni- and bi-acupoint EAS. The results suggested that uni-acupoint method was an effective EAS method and had comparable pain relief effect with bi-acupoint method

Training models using forces computed by stochastic electronic structure methods

Quantum Monte Carlo (QMC) can play a very important role in generating accurate data needed for constructing potential energy surfaces. We argue that QMC has advantages in terms of a smaller systematic bias and an ability to cover phase space more completely. The stochastic noise can ease the training of the machine learning model. We discuss how stochastic errors affect the generation of effective models by analyzing the errors within a linear least squares procedure, finding that there is an advantage to having many relatively imprecise data points for constructing models. We then analyze the effect of noise on a model of many-body silicon finding that noise in some situations improves the resulting model. We then study the effect of QMC noise on two machine learning models of dense hydrogen used in a recent study of its phase diagram. The noise enable us to estimate the errors in the model. We conclude with a discussion of future research problems