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A feedforward-feedback aeration control strategy based on online oxygen requirements (OR) estimation is proposed for oxidation ditch (OD) processes, and it is further developed for intermittent aeration OD processes, which are the most popular type in Japan. For calculating OR, concentrations of influent biochemical oxygen demand (BOD) and total Kjeldahl nitrogen (TKN) are estimated online by the measurement of suspended solids (SS) and sometimes TKN is estimated by NH4-N. Mixed liquor suspended solids (MLSS) and temperature are used to estimate the required oxygen for endogenous respiration. A straightforward parameter named aeration coefficient, Ka, is introduced as the only parameter that can be tuned automatically by feedback control or manually by the operators. Simulation with an activated sludge model was performed in comparison to fixed-interval aeration and satisfying result of OR control strategy was obtained. The OR control strategy has been implemented at seven full-scale OD plants and improvements in nitrogen removal are obtained in all these plants. Among them, the results obtained in Yumoto wastewater treatment plant were presented, in which continuous aeration was applied previously. After implementing intermittent OR control, the total nitrogen concentration was reduced from more than 5 mg/L to under 2 mg/L, and the electricity consumption was reduced by 61.2% for aeration or 21.5% for the whole plant. [ABSTRACT FROM AUTHOR]

Considers the problem of reconstructing of the boundary of an unknown inclusion together with its conductivity from the localized Dirichlet-to-Neumann map. Formula of the map; Calculation of the Dirichlet-to-Neumann map inside the inclusion; Summary of the reconstruction procedure; Construction of singular solutions.

Presents a formula for the reconstruction of the support function for unknown inclusion by means of the Dirichlet to Neumann map. Application of the method to an inverse boundary value problem for the Helmholtz equation; Proof of theorem.

Presents a study which identified the curve of discontinuity of the determinant of the anisotropic conductivity. Theorems; Proofs; Lemmas.

Presents an idea for the proof of a unique determination of the shape of an unknown inclusion having essentially bounded conductivity by means of infinitely many measurements at the boundary. Information on the inverse problem; List of the lemmas.

Reports two mathematical inversion algorithms for the electric impedance tomography. Application to the reconstruction problem of the unknown boundary on which the Neumann derivative of the solution of the Helmholtz equation vanishes.

Podocytes are postmitotic renal glomerular cells with multiple ramifications that extend from the cell body. Processes departing from a podocyte interdigitate with corresponding projections from neighboring cells and form an intricate web that enwraps the glomerular capillary completely. Podocyte processes are interconnected by the slit diaphragm, an adhesion junction mostly formed by Ig-like molecules, cadherins/protocadherins, ephrin/eph, and neurexin molecules organized in an assembly that resembles synaptic junctions. Podocyte failure is primarily or secondarily implicated in all forms of proteinuric glomerular diseases, as confirmed by the morphological changes of their elaborate cell architecture detectable by electron microscopy. Importantly, mutations of podocyte proteins are responsible for the most severe forms of congenital nephrotic syndrome. In the last 15 years, progressive technological advances have aided the study of podocyte biology and pathology, confirming the relevance of podocyte molecules and signaling pathways for the function of the glomerular filter. This review will examine the most important and newest discoveries in the field, which is rapidly evolving, hopefully leading to a detailed knowledge of this fascinating cell and to the development of specific therapeutic options for proteinuric diseases.