An Interaction-Coordination Algorithm with Time- and State-Decompositions for Nonlinear Optimal Control Problems

This paper proposes a computational algorithm for the multilevel control of a composite nonlinear dynamical system with the performance index of a quadratic type. First, for the solution of a linear two-point boundary-value problem (TPBVP), a computational technique, termed time-decomposition, is proposed. The time-decomposition implies decomposition of the system equations along the subintervals of the independent variable. The boundary conditions of each subinterval are determined algebraically in such a way that the continuity condition of the variables at the boundary points is satisfied. This technique plays an important role in the subsequent discussions. Second, a nonlinear optimal control problem is considered. The objective is to minimize the performance index of a quadratic type. For this problem, the authors have previously presented ‘the interaction-coordination algorithm with modified performance index.’ The basic idea of this algorithm is to decompose the overall nonlinear problem into a number of smaller linear subproblems. Here this kind of decomposition is termed state-decomposition. In the present paper, a computational algorithm by use of both the time- and the state-decomposition is proposed. The algorithm essentially constructs a three-level computational structure, and results in a fast convergence even for problems with strong nonlinearities and/or a long control interval

Expression and regulation of Enpp2 in rat uterus during the estrous cycle

Ectonucleotide pyrophosphatase/phosphodiestrase 2 (Enpp2) isolated from the supernatant of human melanoma cells is a lysophospholipase D that transforms lysophosphatidylcholine into lysophospatidic acid. Although multiple analyses have investigated the function of Enpp2 in the hypothalamus, its role in the uterus during the estrous cycle is not well understood. In the present study, rat uterine Enpp2 was analyzed by RT-PCR, Western blotting, and immunohistochemistry. Quantitative PCR analysis demonstrated that uterine Enpp2 mRNA was decreased during estrus compared to proestrus and diestrus. To determine whether uterine Enpp2 expression is affected by sex steroid hormones, immature rats were treated with 17β-estradiol (E2), progesterone, or both on postnatal days 14 to 16. Interestingly, the expression of Enpp2 mRNA and protein were down-regulated by E2 in the uterus during estrus but not during proestrus or diestrus, suggesting that Enpp2 may play a role in uterine function during estrus. Enpp2 is primarily localized in the stromal cells of the endometrium during proestrus and estrus. During diestrus, Enpp2 was highly expressed in the epithelial cells of the endometrium. Taken together, these results suggest that uterine Enpp2 may be regulated by E2 and plays a role in reproductive functions during female rat development

Detection of Antilymphocyte Antibody with Two-Color Method in Systemic Lupus Erythematosus and Its Heterogeneous Specificities against Human T-Cell Subsets

The two-color method originally described by Van Rood et al. (Van Rood, J. J., A. Van Leeuwen, and J. S. Ploen. 1976. Simultaneous detection of two cell populations by two-color fluorescence and application to the recognition of B-cell determinants. Nature (Lond.). 262: 795-797) for the typing of homologous leukocytic antibodies, D-region was used for the detection of antilymphocyte antibody (ALA) in systemic lupus erythematosus. In this method, surface immunoglobulin-bearing cells were identified with fluorescein isothiocyanate-labeled anti-immunoglobulin and nuclei of killed cells were stained with ethidium bromide. Therefore, cell type (T or B) of the target cells can be identified without fractionating them. ALA was detected in 87% of lupus sera and had a preferential reactivity with T cells. Its major immunoglobulin class was shown to be immunoglobulin (Ig)M. The subspecificity of ALA was further analyzed using fractionated T-cell subsets as target cells. When T lymphocytes were separated into Fc receptor-bearing (Tγ) and lacking (Tγ[-]) cells, 64% of ALA showed preferential reactivity with Tγ cells and 14% with Tγ(-) cells. The remainder had no selective reactivity against Tγ or Tγ(-) cells. Tγ cells were shown to have suppressor activity, whereas Tγ(-) cells were indicated to contain helper cells. The above finding was in agreement with the observation that treatment of T cells with ALA that preferentially react with Tγ cells considerably enhanced immunoglobulin synthesis in vitro, whereas treatment of T cells with ALA reactive with Tγ(-) cells clearly suppressed the formation of immunoglobulins. Treatment of ALA with no selective reactivity showed variable effects on in vitro immunoglobulin synthesis. These results indicate that ALA in lupus have heterogeneous specificities against human T-cell subsets

Transport mechanism and affinity of [99mTc]Tc-mercaptoacetyltriglycine ([99mTc]MAG3) on the apical membrane of renal proximal tubule cells

Technetium-99m-labeled mercaptoacetyltriglycine ([99mTc]MAG3) is widely used for evaluation of transplanted kidneys, diagnosis of tubular necrosis, and scintigraphic studies of tubular function. [99mTc]MAG3 is a substrate for organic anion transporter (OAT)1 and OAT3 on the basolateral membrane side for renal secretion. We investigated the transport mechanism and affinity of [99mTc]MAG3 on the apical membrane of renal proximal tubule cells for renal secretion. Adenosine triphosphate-binding cassette (ABC) transporters for renal secretion of [99mTc]MAG3 were examined using ABC transporter vesicles expressing multiple drug resistance 1 (MDR1), breast cancer resistance protein (BCRP), multidrug resistance-associated protein (MRP)2, and MRP4. MK-571, a MRP inhibitor, was applied to measure the Km and Vmax of MRP2 and MRP4 in a vesicle transport assay. Single photon emission computed tomography (SPECT) was performed in normal rats and MRP2-deficient Eisai hyperbilirubinuria rats (EHBR) using [99mTc]MAG3 with and without MK-571. [99mTc]MAG3 uptake in adenosine triphosphate was significantly higher than that in adenosine monophosphate in vesicles that highly expressed MRP2 and MRP4. The affinity of [99mTc]MAG3 for MRP4 was higher than that for MRP2. Renal secretion via MRP2 and MRP4 was identified by comparing normal and EHBR rats with and without MK-571 on SPECT. [99mTc]MAG3 is transported via MRP2 and MRP4 on the apical membrane of renal proximal tubule cells. The affinity of MRP4 is higher than that of MRP2

Measurement of temperature after hypervelocity collision of microparticles in the range from 10 to 40 km/s

The temperature recorded immediately after hypervelocity collision of microparticles comprising iron and nickel with a silver-coated piezoelectric plate was analyzed using photomultipliers of different spectral response characteristics. The conversion rate between the velocity and temperature is estimated to be ~900 K/km/s in the velocity range of 10-40 km/s. This rate is greater than that reported earlier