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The dynamic behavior of the concentration profiles of a single protein in the pore solution and the adsorbed phase is studied in different adsorbent media when the spatial density distribution of the immobilized ligands is either uniform or non‐uniform and at the same time the single protein is forming one‐site and two‐site adsorbate–ligand complexes with the immobilized monovalent ligands. The competition for the formation of one‐site and two‐site interaction complexes leads to the formation of inner radial humps in the concentration profiles of the two‐site adsorbate–ligand complex in adsorbent particles having either uniform or non‐uniform spatial ligand density distributions. The results show that inner radial humps in the concentration profiles of the adsorbed protein (total concentration of adsorbed protein by one‐site and two‐site interactions) occur only in adsorbent media whose spatial ligand density distributions are non‐uniform and have maxima or minima occurring in radial positions located between the center and the outer surface of the particles. The non‐uniform spatial ligand density distributions satisfying this property provide the cause for the occurrence of inner radial humps in the concentration profiles of a single adsorbed protein, while the multi‐site adsorption interactions affect the magnitude and the rate of propagation of the inner radial humps in the concentration profiles of the single adsorbed protein. It is also demonstrated that adsorbent media having certain non‐uniform functional forms of spatial distribution in the density of immobilized ligands could provide more efficient adsorption of a protein than an adsorbent medium whose spatial distribution of the density of immobilized ligands is uniform. Furthermore, the results in this study suggest the type of information that could be obtained from finite bath experiments and could be used to (i) determine whether multi‐site adsorbate–ligand complexes are formed during the adsorption of a single adsorbate and (ii) select between alternative adsorbent media the adsorbent particles that could provide the highest overall adsorption rate for a given adsorbate of interest. The results clearly indicate that it is very important to study the dynamic behavior of an adsorption system having a non‐uniform spatial ligand density distribution and where the values of the pH and ionic strength are such that the electrophoretic effects are active.

A regenerative prescaled clock recovery device based on an optoelectronic version of the Miller divider has been tested in high-bit-rate OTDM systems. Tests at 4×2.5 and 4×10 Gbit/s have been performed to characterize the locking range and the frequency response of the device. The timing jitter of the recovered signal in the case of the 4×10 Gbit/s OTDM system does not exceed 0.5 ps. Finally, a comparison of two bit-error-rate measurements (with and without the clock recovery system) were carried out for the 4×10 Gbit/s OTDM system. The relevant penalty for each channel is negligible, while the maximum received power difference among the four channels at a bit error rate value of 10−10is around 0.7 dB.

Platelet-activating factor (PAF) has been suggested recently to play an important role in immune glomerulonephritis, favoring the formation of immune deposits in glomeruli and contributing to the local inflammatory reaction. Here we sought to investigate whether urinary PAF excretion was modified in New Zealand Black x New Zealand White mice a model of genetically determined immune complex disease which mimics systemic lupus in humans and whether changes in PAF urinary excretion values correlated with the extent of proteinuria. To clarify the possible "in vivo" relevance of these findings we evaluated whether PAF receptor antagonist has any influence on the evolution of renal disease and survival of these mice. Our results showed that: 1) in lupus mice urinary PAF excretion increased progressively with age in New Zealand Black x White; 2) the increase in PAF excretion correlated with the severity of proteinuria; and 3) the chronic administration of a PAF receptor antagonist [L-659,989 [(+/- )-trans-2-(3-methoxy-5-methylsulfonyl-4-propoxyphenyl)-5- (3,4,5-trimethoxyphenyl)tetrahydrofuran]] starting from 26 weeks of age significantly delayed the onset of proteinuria and prolonged survival.

40 Gbit/s OTDM transmission with polarisation-independent demultiplexing is demonstrated over 150 km of SMF. The best demultiplexing conditions are studied and experimentally analysed. The penalty is 0.7 dB at BER = 10–10 and no floor is present down to BER = 10–13.

The first field trial using midspan spectral inversion for dispersion compensation is presented. All-fibre subsystems allow optical time-division multiplexed transmission over 140 km of standard fibre (D = 16 ps/nm/km) with polarisation dependence < 0.2 dB.

A novel polarisation independent demultiplexer based on four wave mixing in a dispersion shifted fibre is proposed using a short, highly birefringent fibre in a forward and backward propagation scheme to allow polarisation diversity operation. The device has been tested with a 4×10 Gbit/s optical time division multiplexing transmitter. Polarisation dependency is less than 0.5 dB and the BER measurement does not show any floor down to 10-13.

Transition path sampling techniques are becoming common approaches in the study of rare events at the molecular scale. More efficient methods, such as transition interface sampling (TIS) and replica exchange transition interface sampling (RETIS), allow the investigation of rare events, for example, chemical reactions and structural/morphological transitions, in a reasonable computational time. Here, we present PyRETIS, a Python library for performing TIS and RETIS simulations. PyRETIS directs molecular dynamics (MD) simulations in order to sample rare events with unbiased dynamics. PyRETIS is designed to be easily interfaced with any molecular simulation package and in the present release, it has been interfaced with GROMACS and CP2K, for classical and ab initio MD simulations, respectively. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)