Linear bipolar OTAs employing exponential‐law circuits

This paper presents design of linear bipolar OTAs, which are composed of two function blocks; one is an exponential‐law circuit and the other is a core cell. Multi‐tanh cells are employed as the core cell. This kind of OTA has lower power dissipation relatively to the conventional multi‐tanh cell. According as the order of the multi‐tanh core cell becomes higher, the number of circuit realization for the core cell increases. For example, we have two OTAs for the core circuit of an emitter‐coupled pair and four OTAs for the doublet core cell. Thus, we consider the generalized OTAs for an arbitrary order n of the core cell and obtain a formula to give the realization number of the linear OTAs for n. According to the formula, there must be eight OTAs in the case of n=3. All of the eight OTAs are examined. Analysis and simulation results show that the OTAs have advantage in their characteristics, such as linear input range, power dissipation, noise, and frequency response. Copyright 2004 John Wiley & Sons, Ltd.     

Meshless analysis of potential problems in three dimensions with the hybrid boundary node method

Combining a modified functional with the moving least‐squares (MLS) approximation, the hybrid boundary node method (Hybrid BNM) is a truly meshless, boundary‐only method. The method may have advantages from the meshless local boundary integral equation (MLBIE) method and also the boundary node method (BNM). In fact, the Hybrid BNN requires only the discrete nodes located on the surface of the domain. The Hybrid BNM has been applied to solve 2D potential problems. In this paper, the Hybrid BNM is extended to solve potential problems in three dimensions. Formulations of the Hybrid BNM for 3D potential problems and the MLS approximation on a generic surface are developed. A general computer code of the Hybrid BNM is implemented in C++. The main drawback of the ‘boundary layer effect’ in the Hybrid BNM in the 2D case is circumvented by an adaptive face integration scheme. The parameters that influence the performance of this method are studied through three different geometries and known analytical fields. Numerical results for the solution of the 3D Laplace's equation show that high convergence rates with mesh refinement and high accuracy are achievable. Copyright © 2004 John Wiley & Sons, Ltd.     

Lymphatic networks in the periodontal tissue and dental pulp as revealed by histochemical study.

The structural organization and fine distribution of the lymphatic networks in the periodontal tissues (gingiva, periodontal membrane, and alveolar process) and dental pulp of animals and humans were reviewed with special reference to histochemical examination by light and electron microscopy. The distinction between lymphatics and blood vessels was made on cryostat sections of undecalcified and calcified teeth treated with EDTA solution and whole mount preparations of periodontal membranes using 5'-nucleotidase (5'-Nase)-alkaline phosphatase (ALPase) double staining. This staining procedure allowed lymphatic vessels in the periodontal tissue and dental pulp to be differentiated from blood vessels. The specificity and localization of the enzyme reactions were confirmed by comparative histochemical studies of the same specimen with light microscopy and scanning or transmission electron microscopy. Well-developed 5'-Nase-positive lymphatic networks were observed on the tissue sections and whole mount preparations of the gingiva, periodontium, and dental pulp. More lymphatic vessels were seen in the root area of the periodontium than in the cervical area. In the dental pulp, lymphatic vessels were more numerous in the central part than in the peripheral odontoblastic layer. These distributions of the lymphatic capillary networks are discussed in relation to their ability to supply lymph to the teeth.     

Lysophosphatidylinositol Induced Morphological Changes and Stress Fiber Formation through the GPR55-RhoA-ROCK Pathway

We previously reported that lysophosphatidylinositol (LPI) functions as an endogenous agonist of GPR55, a novel cannabinoid receptor. However, the physiological roles of LPI-GPR55 have not yet been elucidated in detail. In the present study, we found that LPI induced morphological changes in GPR55-expressing HEK293 cells. LPI induced the cell rounding of GPR55-expressing HEK293 cells but not of empty-vector-transfected cells. LPI also induced the activation of small GTP-binding protein RhoA and increased stress fiber formation in GPR55-expressing HEK293 cells. The inhibition of RhoA and Rho kinase ROCK by the C3 exoenzyme and the ROCK inhibitor reduced LPI-induced cell rounding and stress fiber formation. These results clearly indicated that the LPI-induced morphological changes and the assembly of the cytoskeletons were mediated through the GPR55-RhoA-ROCK pathway.     

Uterine Deletion of Bmal1 Impairs Placental Vascularization and Induces Intrauterine Fetal Death in Mice

Recently, it was demonstrated that the expression of BMAL1 was decreased in the endometrium of women suffering from recurrent spontaneous abortion. To investigate the pathological roles of uterine clock genes during pregnancy, we produced conditional deletion of uterine Bmal1 (cKO) mice and found that cKO mice could receive embryo implantation but not sustain pregnancy. Gene ontology analysis of microarray suggested that uterine NK (uNK) cell function was suppressed in cKO mice. Histological examination revealed the poor formation of maternal vascular spaces in the placenta. In contrast to WT mice, uNK cells in the spongiotrophoblast layer, where maternal uNK cells are directly in contact with fetal trophoblast, hardly expressed an immunosuppressive NK marker, CD161, in cKO mice. By progesterone supplementation, pregnancy could be sustained until the end of pregnancy in some cKO mice. Although this treatment did not improve the structural abnormalities of the placenta, it recruited CD161-positive NK cells into the spongiotrophoblast layer in cKO mice. These findings indicate that the uterine clock system may be critical for pregnancy maintenance after embryo implantation.     

A Knowledge-Based Software Process Simulation Model

In this paper we propose a new software development process simulation model. The model can predict variations of productivity based on dynamic changes in the developer's knowledge structure. An important concept of the model is that a developer's productivity is influenced by the developer's knowledge. Moreover, a developer can acquire new knowledge by executing activities of a project. In other words, the developer's knowledge structure changes during the project. The knowledge structure is defined using a cognitive map that consists of knowledge elements and prerequisite relationships among the knowledge elements. By adding the specific developer's knowledge and the specific project workload to the knowledge structure, an increment of the developer's knowledge and the project progress are calculated into the model. The simulation results are useful for making project plans including technical reviews, which are an efficient technique for acquiring new knowledge. The simulation model can predict what knowledge should be discussed in the technical review, when the review should be held, and who the members of the review should be. The simulation results help managers make the most appropriate and executable project plan.     

Hypotensive effect of a sweetpotato protein digest in spontaneously hypertensive rats and purification of angiotensin I-converting enzyme inhibitory peptides

We have investigated angiotensin I-converting enzyme (ACE) inhibitory activity in an enzyme digest of sweetpotato protein, the antihypertensive effect of the digest in spontaneously hypertensive rats (SHR), and the identification of an ACE inhibitory peptide. Protein was prepared from squeezed juice of sweetpotato by isoelectric focusing precipitation. Three kinds of proteases were selected for effective protein digestion. The digest, sweetpotato peptide (SPP), exhibited strong ACE inhibitory activity (IC₅₀: 18.2 μg/ml). SPP was orally administered by gavage to SHR at a dose of 100 mg/kg or 500 mg/kg. The systolic blood pressure and the diastolic blood pressure were measured at 0 (before administration), 2, 4, 8, and 24 h after administration. A dose-dependent decrease in systolic blood pressure in SHR was observed after oral administration of SPP. Significant differences between SPP-administered rats and control rats were observed 4 and 8 h after administration in the 500 mg/kg-administered group and 8 h after administration in the 100 mg/kg-administered group. Diastolic blood pressure also decreased in the SPP-administered groups, although the difference between SPP-administered rats and control rats was not significant. These results suggest that SPP may be useful in the prevention or treatment of hypertension. Peptides with ACE inhibitory activity were purified from SPP by absorption chromatography and preparative HPLC using an ODS column. The amino acid sequences of isolated peptides were I-T-P, I-I-P, G-Q-Y and S-T-Y-Q-T; their ACE inhibitory activities (IC₅₀) were 9.5 μM, 80.8 μM, 52.3 μM and 300.4 μM, respectively. In conclusion, I-T-P is a novel, strong ACE inhibitory peptide.     

BWR core internals replacement

The core shroud and other internal component (core internals) replacements were carried out at Fukushima-Daiichi unit number three of Tokyo Electric Power Company (TEPCO) in Japan. The project is the first experience of replacement procedures that have been developed for welded core shrouds and jet pumps. The outline and experience of the project are discussed in this paper.