Mutations in NPHS2 are a common cause of focal segmental glomerulosclerosis (FSGS). It was initially assumed that FSGS caused by a genetically defective protein in the native kidney would not recur ...after transplantation; however, description of three patients with NPHS2 missense mutations challenged the validity of this assumption. A possible mechanism of recurrence in cases with stop‐codon mutations is the formation of auto‐antibodies against the truncated protein. In this case report, we describe a 9‐year‐old girl with the R138X NPHS2 mutation who presented with recurrent nephrotic syndrome 4 years after renal transplantation from a deceased donor, and was treated with plasmapheresis with a partial response. Renal histology did not demonstrate glomerular immunoglobulin deposition and an extensive search for anti‐podocin antibodies based on indirect Western blot with recombinant podocin, was negative, as was the test for glomerular permeability factor (Palb). Taken together these findings confirm the possibility of post transplantation nephrotic syndrome in patients with NPHS2 mutations. Lack of immunoglobulin deposition, absence of circulating anti‐podocin antibodies, and normal Palb suggest that other, unknown pathogenetic mechanisms are implicated.
In this child with steroid resistent nephrotic syndrome due to mutation in podocin, with late recurrence of proteinuria, no antibodies to podocin were detected.
In this paper, we apply to (almost) all the “named” polynomials of the Askey scheme, as defined by their standard three-term recursion relations, the machinery developed in previous papers. For each ...of these polynomials we identify at least one additional recursion relation involving a shift in some of the parameters they feature, and for several of these polynomials characterized by special values of their parameters, factorizations are identified yielding some or all of their zeros—generally given by simple expressions in terms of integers (Diophantine relations). The factorization findings generally are applicable for values of the Askey polynomials that extend beyond those for which the standard orthogonality relations hold. Most of these results are not (yet) reported in the standard compilations.
We introduce an extension of the factorization-decomposition technique that allows us to manufacture new solvable nonlinear matrix evolution equations. Several examples of such equations are reported.
The ethanol steam reforming (ESR) is studied in a parallel plate reactor with square channels of 500–2000 μm and washcoated with Pd-based catalyst. The endothermic process is co- or countercurrently ...heated by means of a flue gas stream flowing through contiguous channels. Two contiguous square channels, assumed as representative of the whole reactor behavior, are simulated using both 1D pseudohomogeneous and heterogeneous models for comparison purposes. The influence of the main operating variables, flow configuration and design parameters on the performance of the reformer has been analyzed.
The reactor performance is mainly controlled by the heat supply from the flue gas to the process stream. For low inlet temperatures of the ethanol + water feed, the countercurrent flow configuration allows improved heat recuperation and the reactor shows a higher performance. Conversely, when the feed is pre-heated upstream the reactor, the cocurrent scheme appears preferable due to a more favorable axial profile of heat transferred. The channel width has a strong influence on the hydrogen production rate and the residual methane slips when cocurrent operation is selected. For the countercurrent scheme, a more robust design is achieved in terms of ethanol conversion and hydrogen yield for variations in the feed temperature. Moreover, the channel dimension losses influence provided enough small channels are considered. The heat conduction phenomenon through the solid metal wall was studied varying the wall thickness; diminished reactor performance for thicker walls was observed due to a drop in the heat duty.
A new generation of high-resolution hypernuclear γ-spectroscopy experiments using high-purity germanium (HPGe) detectors is presently designed for the FINUDA spectrometer at DAΦNE, the Frascati ...Φ-factory, and for PANDA, the p–p¯ hadron spectrometer at the future FAIR facility. In both spectrometers the HPGe detectors have to be operated in strong magnetic fields. In this paper we report on a series of measurements performed on a HPGe detector inserted in a magnetic field of intensity up to 2.5T, the highest ever reached for operations with a HPGe, and with different orientations of the detector's axis with respect to field direction. A significant worsening of the energy resolution was found, but with a moderate loss of the efficiency. The most relevant features of the peak shapes, described by bi-Gaussian functions, are parametrized in terms of field intensity and energy: this allows to correct the spectra measured in magnetic field and to recover the energy resolution almost completely.
The metal-sulphur active sites of hydrogenases catalyse hydrogen evolution or uptake at rapid rates. Understanding the structure and function of these active sites-through mechanistic studies of ...hydrogenases, synthetic assemblies and in silico models-will help guide the design of new materials for hydrogen production or uptake. Here we report the assembly of the iron-sulphur framework of the active site of iron-only hydrogenase (the H-cluster), and show that it functions as an electrocatalyst for proton reduction. Through linking of a di-iron subsite to a {4Fe4S} cluster, we achieve the first synthesis of a metallosulphur cluster core involved in small-molecule catalysis. In addition to advancing our understanding of the natural biological system, the availability of an active, free-standing analogue of the H-cluster may enable us to develop useful electrocatalytic materials for application in, for example, reversible hydrogen fuel cells. (Platinum is currently the preferred electrocatalyst for such applications, but is expensive, limited in availability and, in the long term, unsustainable.)
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Several completely
integrable, indeed
solvable, Hamiltonian many-body problems are exhibited, characterized by Newtonian equations of motion (“acceleration equal force”), with linear and cubic ...forces, in
N-dimensional space (
N being an arbitrary positive integer, with special attention to
N=2, namely, motions in a plane, and
N=3, namely, motions in ordinary three-dimensional space). All the equations of motion are written in covariant form (“
N-vector equal
N-vector”), entailing their rotational invariance. The corresponding Hamiltonians are of normal type, with the kinetic energy quadratic in the canonical momenta, and the potential energy quadratic and quartic in the canonical coordinates.
Recently we highlighted the remarkable nature of an explicitly invertible transformation, we reported some generalizations of it and examples of its expediency in several mathematical contexts: ...algebraic and Diophantine equations, dynamical systems (with continuous and discrete time), nonlinear PDEs, analytical geometry, functional equations. In this paper we report a significant generalization of this approach and we again illustrate via some analogous examples its expediency to identify problems which appear far from trivial but are in fact explicitly solvable.
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