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

Studies on In Vitro Antioxidant Activity of Methanolic Extract and Fractions of Ficus Hispida Lin. Fruits

The present study was designed to confirm the traditional use of the fruits of Ficus hispida Linn. (Moraceae) as an antioxidant agent. Fruits of the plant extracted with methanol and crude methanol extract (CME) were further fractionated with n-hexane, chloroform, and ethyl acetate. All the fractions, n-hexane (NHF), chloroform (CHF), ethyl acetate (EAF), aqueous (AQF) and CME were preliminary screened for in vitro antioxidant activity and total phenolic and total flavonoid content. In DPPH radical scavenging assay, CME exhibited highest scavenging activity (IC50 = 11.20 µg/mL) as compared to other fractions. In this assay, IC50 of reference standard BHT was 5.10 µg/mL. The reducing power of the samples was in the order as AQF > CME > CHF > EAF > NHF. The results for hydrogen peroxide scavenging activity indicated that CME, EAF and AQF had almost the same scavenging activity except NHF. Total antioxidant capacity of CME and other fractions were ranked as CHF > AQF > CME > EAF > NHF.  In the assay of antioxidant constituents (total phenol and total flavonoids content), the CME had highest phenolic and flavonoids content. The results indicate that Ficus hispida fruits could be considered as a potential source of natural antioxidant

Agreement between Thyroid Uptake of 99mTc Pertechnetate and 131I in Hyperthyroid Patients

&lt;p&gt;&lt;strong&gt;Objectives&lt;/strong&gt;: With the advancement of science, the scope of 131 I thyroid uptake in diagnosis and treatment of thyroid diseases has become limited. Uptake test with 99m Technetium (99mTc) pertechnetate along with a thyroid scan, which are done almost routinely, could be a better option when required. This will not only exempt the patients from relatively higher radiation burden of 131I but will also cause significant reduction of procedural time. Moreover, the thyroid image we get along with the uptake may guide with additional information. This study was done to provide preliminary data regarding thyroid uptake test with 99mTc in our population &amp;amp; to assess the possibilities of introducing this safer and convenient radionuclide in our routine practice.&lt;strong&gt; &lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Patients and methods:&lt;/strong&gt; This cross sectional, comparative study was conducted from January to December of 2015 on 27 participants in Institute of Nuclear Medicine and Allied Sciences, Dhaka. Hyperthyroid patients coming for a radioactive iodine uptake test along with a thyroid scan were enrolled. Uptake of 99mTc pertechnetate at 20 minutes and 131I at 24 hours were measured.  &lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Among 27 participants, 25 had raised, 2 had normal 131I uptake. Two normal values of 99m Tc uptake were found and rest showed high uptake. Two patients had high uptakes in both the method but 131 I uptake was extremely high (90% and 80%) in comparison to 99mTc uptake (10% and 7% respectively). Statistical analysis revealed a moderate agreement (k=0.5) along with a moderate positive correlation (r=0.6) between the two uptake methods.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion:&lt;/strong&gt; Good agreement and correlation were found between two modalities of thyroid uptake in case of hyperthyroid patients. So, 99mTc may be considered for uptake test in a regular basis in the limited fields where an uptake is still required as it may yield a reliable result in a simple, quicker and more convenient way.&lt;/p&gt;&lt;p&gt;Bangladesh J. Nuclear Med. 19(2): 89-91, July 2016&lt;/p&gt;</jats:p