Review of Unbiased FIR Filters, Smoothers, and Predictors for Polynomial Signals

Extracting an estimate of a slowly varying signal corrupted by noise is a common task. Examples can be found in industrial, scientific and biomedical instrumentation. Depending on the nature of the application the signal estimate is allowed to be a delayed estimate of the original signal or, in the other extreme, no delay is tolerated. These cases are commonly referred to as filtering, prediction, and smoothing depending on the amount of advance or lag between the input data set and the output data set. In this review paper we provide a comprehensive set of design and analysis tools for designing unbiased FIR filters, predictors, and smoothers for slowly varying signals, i.e. signals that can be modeled by low order polynomials. Explicit expressions of parameters needed in practical implementations are given. Real life examples are provided including cases where the method is extended to signals that are piecewise slowly varying. A critical view on recursive implementations of the algorithms is provided

Unbiased, optimal, and in-betweens: the trade-off in discrete finite impulse response filtering

In this survey, the authors examine the trade-off between the unbiased, optimal, and in-between solutions in finite impulse response (FIR) filtering. Specifically, they refer to linear discrete real-time invariant state-space models with zero mean noise sources having arbitrary covariances (not obligatorily delta shaped) and distributions (not obligatorily Gaussian). They systematically analyse the following batch filtering algorithms: unbiased FIR (UFIR) subject to the unbiasedness condition, optimal FIR (OFIR) which minimises the mean square error (MSE), OFIR with embedded unbiasedness (EU) which minimises the MSE subject to the unbiasedness constraint, and optimal UFIR (OUFIR) which minimises the MSE in the UFIR estimate. Based on extensive investigations of the polynomial and harmonic models, the authors show that the OFIR-EU and OUFIR filters have higher immunity against errors in the noise statistics and better robustness against temporary model uncertainties than the OFIR and Kalman filters

False discovery rate estimation and heterobifunctional cross-linkers

<div><p>False discovery rate (FDR) estimation is a cornerstone of proteomics that has recently been adapted to cross-linking/mass spectrometry. Here we demonstrate that heterobifunctional cross-linkers, while theoretically different from homobifunctional cross-linkers, need not be considered separately in practice. We develop and then evaluate the impact of applying a correct FDR formula for use of heterobifunctional cross-linkers and conclude that there are minimal practical advantages. Hence a single formula can be applied to data generated from the many different non-cleavable cross-linkers.</p></div

Growth of dilute quaternary alloy InPNBi and its? characterization

International audienceInPNBi alloy semiconductor is grown for the first time on InP substrates by liquid phase epitaxy (LPE) technique by adding minute amounts of polycrystalline InN and Bi to the growth melt (upto 3 wt% of InN and 3 wt% of Bi in the melt). Energy dispersive X-ray (EDX) spectroscopy shows the presence of Bi and N in the material. Crystalline quality of the layer and the lattice contraction and dilation with respect to the substrate are demonstrated by high resolution X-Ray diffraction (HRXRD) measurements on layers containing N and Bi in different ratios. This result is qualitatively substantiated from the values of N and Bi contents obtained from the analysis of the X-ray photoelectron spectroscopy (XPS) measurements performed on each layer. XPS further provides details of the N and Bi bonding with In in the lattice. Raman spectroscopy measurements are done on the layers to investigate the different vibrational modes associated with the constituent elements and their bonds. 10 K photoluminescence (PL) indicate band gap reduction in the alloy upto 63 meV due to the incorporation of N and Bi atoms at the P sites of the InP lattice

A C-Terminal Region of Yersinia pestis YscD Binds the Outer Membrane Secretin YscC▿†

YscD is an essential component of the plasmid pCD1-encoded type III secretion system (T3SS) of Yersinia pestis. YscD has a single transmembrane (TM) domain that connects a small N-terminal cytoplasmic region (residues 1 to 121) to a larger periplasmic region (residues 143 to 419). Deletion analyses established that both the N-terminal cytoplasmic region and the C-terminal periplasmic region are required for YscD function. Smaller targeted deletions demonstrated that a predicted cytoplasmic forkhead-associated (FHA) domain is also required to assemble a functional T3SS; in contrast, a predicted periplasmic phospholipid binding (BON) domain and a putative periplasmic “ring-building motif” domain of YscD could be deleted with no significant effect on the T3S process. Although deletion of the putative “ring-building motif” domain did not disrupt T3S activity per se, the calcium-dependent regulation of the T3S apparatus was affected. The extreme C-terminal region of YscD (residues 354 to 419) was essential for secretion activity and had a strong dominant-negative effect on the T3S process when exported to the periplasm of the wild-type parent strain. Coimmunoprecipitation studies demonstrated that this region of YscD mediates the interaction of YscD with the outer membrane YscC secretin complex. Finally, replacement of the YscD TM domain with a TM domain of dissimilar sequence had no effect on the T3S process, indicating that the TM domain has no sequence-specific function in the assembly or function of the T3SS