Maximum error modeling for fault-tolerant computation using maximum a posteriori (MAP) hypothesis

The application of current generation computing machines in safety-centric applications like implantable biomedical chips and automobile safety has immensely increased the need for reviewing the worst-case error behavior of computing devices for fault-tolerant computation. In this work, we propose an exact probabilistic error model that can compute the maximum error over all possible input space in a circuit-specific manner and can handle various types of structural dependencies in the circuit. We also provide the worst-case input vector, which has the highest probability to generate an erroneous output, for any given logic circuit. We also present a study of circuit-specific error bounds for fault-tolerant computation in heterogeneous circuits using the maximum error computed for each circuit. We model the error estimation problem as a maximum a posteriori (MAP) estimate [28] and [29], over the joint error probability function of the entire circuit, calculated efficiently through an intelligent search of the entire input space using probabilistic traversal of a binary Join tree using Shenoy-Shafer algorithm [20] and [21]. We demonstrate this model using MCNC and ISCAS benchmark circuits and validate it using an equivalent HSpice model. Both results yield the same worst-case input vectors and the highest percentage difference of our error model over HSpice is just 1.23%. We observe that the maximum error probabilities are significantly larger than the average error probabilities, and provides a much tighter error bounds for fault-tolerant computation. We also find that the error estimates depend on the specific circuit structure and the maximum error probabilities are sensitive to the individual gate failure probabilities.     

A noise constrained least mean fourth (NCLMF) adaptive algorithm

The learning speed of an adaptive algorithm can be improved by properly constraining the cost function of the adaptive algorithm. In this work, a noise-constrained least mean fourth (NCLMF) adaptive algorithm is proposed. The NCLMF algorithm is obtained by constraining the cost function of the standard LMF algorithm to the fourth-order moment of the additive noise. The NCLMF algorithm can be seen as a variable step-size LMF algorithm. The main aim of this work is to derive the NCLMF adaptive algorithm, analyze its convergence behavior, and assess its performance in different noise environments. Furthermore, the analysis of the proposed NCLMF algorithm is carried out using the concept of energy conservation. Finally, a number of simulation results are carried out to corroborate the theoretical findings, and as expected, improved performance is obtained through the use of this technique over the traditional LMF algorithm.     

An Indian test facility to characterise diagnostic neutral beam for ITER

The diagnostic neutral beam (DNB) line shall be used to diagnose the He ash content in the D–T phase of the ITER machine using the charge exchange recombination spectroscopy (CXRS). Implementation of a successful DNB at ITER requires several challenges related to the production, neutralization and transport of the neutral beam over path lengths of 20.665 m, to be overcome. The delivery is aided if the above effects are tested prior to onsite commissioning. As DNB is a procurement package for INDIA, an ITER approved Indian test facility, INTF, is under construction at Institute for Plasma Research (IPR), India and is envisaged to be operational in 2015. The timeline for this facility is synchronized with the RADI, ELISE (IPP, Garching), SPIDER (RFX, Padova) in a manner that best utilization of configurational inputs available from them are incorporated in the design. This paper describes the facility in detail and discusses the experiments planned to optimise the beam transmission and testing of the beam line components using various diagnostics.     

Mechanism of Infrared Detection and Transduction by Beetle Melanophila Acuminata In memory of Jerry Wolken

The Melanophila acuminata beetle is attracted to forest fires via a pair of infrared sensory organs composed of sensilla. Our histological work showed that each sensillum contains lipid layers surrounding a protein layer and a unique polysaccharide base that is associated with a neuron to each sensillum. Infrared microscopy showed that the protein region maximally absorbs infrared radiation at 3 μm wavelength and at 10 μm, which corresponds to the known radiation produced by forest fires at 3 μm.Mathematical calculations showed that the physical properties of the sensilla are such that the expected temperature rise is insufficient for transduction of the infrared signal through mechanical means or as a thermal receptor as previously thought;hence the protein plays the pivotal role in perception of single photons and transmission of the signal within the sensilla.     

Complaint-based surveillance for foodborne illness in the United States: a survey of local health departments

Foodborne illnesses are an important public health problem in the United States in terms of both the burden of illness and cost to the health care system. Strengthening foodborne illness surveillance helps address the growing issues of food safety in the United States. Very little is known about the use of consumer complaint surveillance systems for foodborne illness. This study evaluates the use of these surveillance systems by local health departments (LHDs) in the United States and their practices and policies for investigating complaints. Data for this study were collected through two Web-based surveys based on a representative sample of LHDs in the United States; 81% of LHDs use complaint-based surveillance. Of those that did not have a complaint system, 64% reported that the state health department or another agency ran their complaint system. Health departments collect a wide variety of information from callers through their complaint systems, including food intake history. Most of the LHDs, however, do not store the information in an electronic database. Outbreak rates and complaint rates were found to be positively correlated, with a Pearson's correlation coefficient of 0.38. Complaints were the most common outbreak detection mechanism reported by respondents, with a median of 69% of outbreaks during the previous year found through complaints. Complaint systems are commonly used in the United States. Increasing the rate at which illnesses are reported by the public and improving investigation practices could help increase the number of outbreaks detected through complaint surveillance.     

Yogurt can beneficially affect blood contributors of cardiovascular health status in hypertensive rats

Cardiovascular disease is the single leading cause of death in the world and elevated blood pressure is one of the major independent risk factors. Angiotensin-I-converting enzyme-inhibitors have received considerable attention for their effectiveness in both the prevention and the treatment of hypertension. To confirm the antihypertensive effect, the influence of yogurt- and probiotic yogurt-based diets on the weight gain, serum lipid profile, and blood pressure (BP) were investigated in spontaneously hypertensive rats (14 wk old). A total of 3 dietary treatments were fed for 8 wk: skim milk diet (Feed-C), skim milk diet supplemented with freeze dried low fat yogurt (Feed-Y), and with freeze dried low-fat probiotic yogurt (Feed-PY). The total weight gain for the 8-wk period was maximum in rats fed Feed-C (90 g) followed by those fed Feed-PY (85.7 g) and Feed-Y (78.7 g), indicating that the overall weight gains were lesser (statistically non-significant) in the groups fed yogurt containing diets. At the end of the feeding period the reduction in systolic BP of rats fed Feed-Y was 3.7% (-9.5 mm Hg) and 2.7% (-6.4 mm Hg) in those fed Feed-PY while reduction in diastolic BP was 30% (-9.4 mm Hg) and 44% (-13.8 mm Hg), respectively, in comparison to those fed Feed-C. The levels of total cholesterol and low density lipoprotein-cholesterol of rats fed the supplemented diets were lower than those fed Feed-C while no changes in the levels of high density lipoprotein-cholesterol were observed. It was concluded that feeding diets supplemented with yogurts exhibited antihypertensive and hypocholesterolemic effects in spontaneously hypertensive rats.     

Molecular Basis for the Activation of Human Innate Immune Response by the Flagellin Derived from Plant-Pathogenic Bacterium,Acidovorax avenae

Acidovorax avenae is a flagellated, pathogenic bacterium to various plant crops that has also been found in human patients with haematological malignancy, fever, and sepsis; however, the exact mechanism for infection in humans is not known. We hypothesized that the human innate immune system could be responsive to the purified flagellin isolated from A. avenae, named FLA-AA. We observed the secretion of inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and IL-8 by treating FLA-AA to human dermal fibroblasts, as well as macrophages. This response was exclusively through TLR5, which was confirmed by using TLR5-overexpression cell line, 293/hTLR5, as well as TLR5-specific inhibitor, TH1020. We also observed the secretion of inflammatory cytokine, IL-1β, by the activation of NLRC4 with FLA-AA. Overall, our results provide a molecular basis for the inflammatory response caused by FLA-AA in cell-based assays.     

Production and Stability Studies of a Neurotoxin Produced by Clostridium sp. RKD

ABSTRACT: A neurotoxigenic Clostridium sp. (RKD) isolated from intestine of decaying fish produced a neurotoxin that was neutralized by botulinum antitoxin (A+B+E) when tested by mouse protection bioassay. An amplicon of expected size (approximately 700 bp) was generated with primers specific for BoNT/B. Toxin was maximally released in the culture supernatant in the late stationary phase and was dependent on media composition. Growth was optimal in trypticase peptone yeast-extract glucose (TPYG) medium in a pH range of 7.5 to 8.0 and at a temperature between 35°C to 40°C while toxin production was optimum at 37°C (3 to 4 × 10³ minimum lethal dose per milliliter) without any protease treatment. There was no correlation between growth and toxin production when cells were grown in media containing different concentrations of NaCl (0% to 5%). Toxin in the culture supernatant was more stable (50% reduction at 50°C in 90 min) than the partially purified fraction. Toxicity was destroyed gradually after increasing the number of freeze-thaw cycles and was almost completely inactivated after 5 cycles. It was completely inactivated by overnight treatment of 1 N NaOH while it retained 1.5% activity with a similar treatment with 1 N HCl.     

The effect of sodium chloride substitution with potassium chloride on texture profile and microstructure of Halloumi cheese

The effect of partial substitution of NaCl with KCl on texture profile and microstructure of Halloumi cheese was investigated. Four batches of Halloumi cheese were made and kept in 4 different brine solutions (18%, wt/wt), including A) NaCl only, B) 3NaCl:1KCl, C) 1NaCl:1KCl, and D) 1NaCl:3KCl and then stored at 4°C for 56 d. The texture profile was analyzed using an Instron universal machine, whereas an environmental scanning electron microscope was used to investigate the effect of NaCl substitution on the microstructure of cheeses. No significant difference was found in hardness, cohesiveness, adhesiveness, and gumminess among experimental cheeses at the same storage day. Hardness, cohesiveness, and gumminess decreased significantly during storage period with the same salt treatment, whereas adhesiveness significantly increased. Environmental scanning electron microscope micrographs showed a compact and closed texture for cheeses at the same storage period. The microstructure of all cheeses became more closed and compact with storage period. Calcium content negatively correlated with hardness and Na and K contents during storage with the same salt treatment.