Approximate MAP Decoding on Tail-Biting Trellises

We propose two approximate algorithms for MAP decoding on tail-biting trellises. The algorithms work on a subset of nodes of the tail-biting trellis, judiciously selected. We report the results of simulations on an AWGN channel using the approximate algorithms on tail-biting trellises for the $(24,12)$ Extended Golay Code and a rate 1/2 convolutional code with memory 6.Comment: 5 pages, 2 figures, ISIT 200

Least squares DOA estimation with an informed phase unwrapping and full bandwidth robustness

The weighted least-squares (WLS) direction-of-arrival estimator that minimizes an error based on interchannel phase differences is both computationally simple and flexible. However, the approach has several limitations, including an inability to cope with spatial aliasing and a sensitivity to phase wrapping. The recently proposed phase wrapping robust (PWR)-WLS estimator addresses the latter of these issues, but requires solving a nonconvex optimization problem. In this contribution, we focus on both of the described shortcomings. First, a conceptually simpler alternative to PWR is presented that performs comparably given a good initial estimate. This newly proposed method relies on an unwrapping of the phase differences vector. Secondly, it is demonstrated that all microphone pairs can be utilized at all frequencies with both estimators. When incorporating information from other frequency bins, this permits a localization above the spatial aliasing frequency of the array. Experimental results show that a considerable performance improvement is possible, particularly for arrays with a large microphone spacing

A cellulose-based bioassay for the colorimetric detection of pathogen DNA

Cellulose-paper-based colorimetric bioassays may be used at the point of sampling without sophisticated equipment. This study reports the development of a colorimetric bioassay based on cellulose that can detect pathogen DNA. The detection was based on covalently attached single-stranded DNA probes and visual analysis. A cellulose surface functionalized with tosyl groups was prepared by the N,N-dimethylacetamide-lithium chloride method. Tosylation of cellulose was confirmed by scanning electron microscopy, Fourier transform infrared spectroscopy and elemental analysis. Sulfhydryl-modified oligonucleotide probes complementary to a segment of the DNA sequence IS6110 of Mycobacterium tuberculosis were covalently immobilized on the tosylated cellulose. On hybridization of biotin-labelled DNA oligonucleotides with these probes, a colorimetric signal was obtained with streptavidin-conjugated horseradish peroxidase catalysing the oxidation of tetramethylbenzamidine by H2O2. The colour intensity was significantly reduced when the bioassay was subjected to DNA oligonucleotide of randomized base composition. Initial experiments have shown a sensitivity of 0.1 μM. A high probe immobilization efficiency (more than 90 %) was observed with a detection limit of 0.1 μM, corresponding to an absolute amount of 10 pmol. The detection of M. tuberculosis DNA was demonstrated using this technique coupled with PCR for biotinylation of the DNA. This work shows the potential use of tosylated cellulose as the basis for point-of-sampling bioassays.Peer reviewedFinal Accepted Versio

The canonical controller and its regularity

This paper deals with properties of canonical controllers. We first specify the behavior that they implement. It follows that a canonical controller implements the desired controlled behavior if and only if the desired behavior is implementable. We subsequently investigate the regularity of the controlled behavior. We prove that a canonical controller is regular if and only if every controller is regular. In other words, canonical controllers are maximally irregular

Agro-environmental project duration and effectiveness in South-east Asia

Considerable emphasis has been placed on developing technologies for agricultural sustainability. Many bilateral projects are working to achieve this outcome. A desk review was conducted to study the importance of project duration for the effectiveness of sustainable agricultural projects. Longer-duration projects were successful in addressing more holistic issues than short projects. However, funding agencies tend to fund shorter-duration projects, so projects become progressively shorter. At the same time, the number of projects implemented each year is increasing. Despite the decrease in total development assistance, increases in project numbers, particularly since 1986, appear to be at the cost of project duration. Short project duration was one of the most cited reasons for not completing essential dissemination activities for wider adoption, whereas longer- duration projects were usually considered more successful in addressing more holistic issues. It is difficult to produce tangible outputs from agricultural and soil conservation projects within five years. Considering the slow changes in the system and in agricultural and environmental sustainability, the authors suggest that project developers should be advised to plan for a minimum of 5–10 years, depending on the nature of activities. It is time for funding agencies to reconsider their tendency to fund shorter-duration projects

Sensitivity and Linearity of Superconducting Radio-Frequency Single-Electron Transistors: Effects of Quantum Charge Fluctuations

We have investigated the effects of quantum fluctuations of quasiparticles on the operation of superconducting radio-frequency single-electron transistors (RF-SETs) for large values of the quasiparticle cotunneling parameter $\alpha=8E_{J}/E_{c}$, where $E_{J}$ and $E_{c}$ are the Josephson and charging energies. We find that for $\alpha>1$, subgap RF-SET operation is still feasible despite quantum fluctuations that renormalize the SET charging energy and wash out quasiparticle tunneling thresholds. Surprisingly, such RF-SETs show linearity and signal-to-noise ratio superior to those obtained when quantum fluctuations are weak, while still demonstrating excellent charge sensitivity.Comment: Submitted to Phys. Rev. Let

Randomised trial of mefenamic acid versus tranexamic acid in management of menorrhagia

Background: The objective of the study was to compare the efficacy of mefenamic acid, a non-inflammatory drug with tranexamic acid, an antifibrinolytic drug in management of menorrhaghia.Methods: Randomised trial of women attending outpatient department of St. Philomena’s hospital, Bangalore with complaints of menorrhagia. Fifty four patients with complaints of menorrhagia were randomly assigned to receive either mefenamic acid 500 mg tid (group A- 24 patients) or tranexamic acid 1 gm TID (group B- 26 patients) from day one to day five for three consecutive menstrual cycles.Results: Reduction in menstrual blood loss as assessed by pictoral blood loss assessment chart was more in group B (50%) than in Group A (30%) (ANOVA, covariates with F=59.647, p0.05).Conclusions: Both mefenamic acid and tranexamic acid were effective in management of menorrhagia. Tranexamic acid was significantly superior to mefenamic acid in terms of reduction in menstrual blood loss