359 research outputs found
Efficient protection of the pipeline core for safety-critical processor-based systems
The increasing number of safety-critical commercial
applications has generated a need for components with high
levels of reliability. As CMOS process sizes continue to shrink,
the reliability of ICs is negatively affected since they become
more sensitive to transient faults. New circuit designs must take
this fact into consideration, and incorporate adequate protection
against the effects of transient faults. This paper presents a
novel method for protecting the pipelined execution unit of an
embedded processor. It is based on a self-configured architecture
with hybrid redundancy that can mask single and multiple
errors, which can occur on storage elements due to transient
or permanent faults. This concept can be easily applied to any
processing architecture of this nature with a high safety integrity
level. Results from error-injection experiments are also reported
that show that this design can maintain a non-interrupted and
failure-free operation under single and double errors with a
probability that exceeds 99.4%
Study of the effects of SEU-induced faults on a pipeline protected microprocessor
This paper presents a detailed analysis of the behavior of a novel fault-tolerant 32-bit embedded CPU as compared to a
default (non-fault-tolerant) implementation of the same processor during a fault injection campaign of single and double faults. The
fault-tolerant processor tested is characterized by per-cycle voting of microarchitectural and the flop-based architectural states,
redundancy at the pipeline level, and a distributed voting scheme. Its fault-tolerant behavior is characterized for three different
workloads from the automotive application domain. The study proposes statistical methods for both the single and dual fault injection
campaigns and demonstrates the fault-tolerant capability of both processors in terms of fault latencies, the probability of fault
manifestation, and the behavior of latent faults
Betanin dye extracted from ayrampo (<em>Opuntia soehrensii</em>) seeds to develop dye-sensitized solar cells
High Temperature Laser Sintering: An investigation into mechanical properties and shrinkage characteristics of Poly (Ether Ketone) structures
Copyright © 2014 Elsevier. NOTICE: this is the author’s version of a work that was accepted for publication in Materials and Design. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Materials and Design, Vol. 61 (2014). DOI: 10.1016/j.matdes.2014.04.035This paper presents an investigation into the properties of Poly Ether Ketone (PEK) components using the commercial high temperature laser sintering system, EOSINT P800. The shrinkage and the mechanical performance of components across the entire build chamber have been tested and a non-linear shrinkage profile has been obtained. The middle of the build chamber recorded the highest degree of shrinkage and the shrinkage in Z direction had the largest variation. The laser sintered components built in X and Y directions recorded a 10% lower tensile strength than the injection moulded samples of the same material where those built in the Z direction showed an approximately 50% decrease in strength in comparison with the injection moulded test specimens. The crystallinity between the skin and the core of the sintered samples was different; varied with the position within the build chamber and coincided with noticeable sample colour changes
Comparison of gene expression microarray data with count-based RNA measurements informs microarray interpretation.
BACKGROUND: Although numerous investigations have compared gene expression microarray platforms, preprocessing methods and batch correction algorithms using constructed spike-in or dilution datasets, there remains a paucity of studies examining the properties of microarray data using diverse biological samples. Most microarray experiments seek to identify subtle differences between samples with variable background noise, a scenario poorly represented by constructed datasets. Thus, microarray users lack important information regarding the complexities introduced in real-world experimental settings. The recent development of a multiplexed, digital technology for nucleic acid measurement enables counting of individual RNA molecules without amplification and, for the first time, permits such a study. RESULTS: Using a set of human leukocyte subset RNA samples, we compared previously acquired microarray expression values with RNA molecule counts determined by the nCounter Analysis System (NanoString Technologies) in selected genes. We found that gene measurements across samples correlated well between the two platforms, particularly for high-variance genes, while genes deemed unexpressed by the nCounter generally had both low expression and low variance on the microarray. Confirming previous findings from spike-in and dilution datasets, this "gold-standard" comparison demonstrated signal compression that varied dramatically by expression level and, to a lesser extent, by dataset. Most importantly, examination of three different cell types revealed that noise levels differed across tissues. CONCLUSIONS: Microarray measurements generally correlate with relative RNA molecule counts within optimal ranges but suffer from expression-dependent accuracy bias and precision that varies across datasets. We urge microarray users to consider expression-level effects in signal interpretation and to evaluate noise properties in each dataset independently
Affinity maturation generates greatly improved xyloglucan-specific carbohydrate binding modules
<p>Abstract</p> <p>Background</p> <p>Molecular evolution of carbohydrate binding modules (CBM) is a new approach for the generation of glycan-specific molecular probes. To date, the possibility of performing affinity maturation on CBM has not been investigated. In this study we show that binding characteristics such as affinity can be improved for CBM generated from the CBM4-2 scaffold by using random mutagenesis in combination with phage display technology.</p> <p>Results</p> <p>Two modified proteins with greatly improved affinity for xyloglucan, a key polysaccharide abundant in the plant kingdom crucial for providing plant support, were generated. Both improved modules differ from other existing xyloglucan probes by binding to galactose-decorated subunits of xyloglucan. The usefulness of the evolved binders was verified by staining of plant sections, where they performed better than the xyloglucan-binding module from which they had been derived. They discriminated non-fucosylated from fucosylated xyloglucan as shown by their ability to stain only the endosperm, rich in non-fucosylated xyloglucan, but not the integument rich in fucosylated xyloglucan, on tamarind seed sections.</p> <p>Conclusion</p> <p>We conclude that affinity maturation of CBM selected from molecular libraries based on the CBM4-2 scaffold is possible and has the potential to generate new analytical tools for detection of plant carbohydrates.</p
True interindividual variability exists in postprandial appetite responses in healthy men but is not moderated by the FTO genotype
Background: After meal ingestion, a series of coordinated hormone responses occur
concomitantly with changes in perceived appetite. It is not known whether interindividual
variability in appetite exists in response to a meal. Objectives: This study aimed to 1) assess
the reproducibility of appetite responses to a meal; 2) quantify individual differences in
responses; and 3) explore any moderating influence of the fat mass and obesity associated
(FTO) gene. Methods: Using a replicated crossover design, 18 healthy men (mean ± SD 28.5
± 9.8 years, 27.0 ± 5.0 kg·m-2
) recruited according to FTO genotype (9 AA, 9 TT) completed
two identical control and two identical standardized meal conditions (5025 kJ) in randomized
sequences. Perceived appetite and plasma acylated ghrelin, total peptide YY (PYY), insulin
and glucose concentrations were measured before and after interventions as primary
outcomes. Interindividual differences were explored using Pearson’s product-moment
correlations between the first and second replicate of the control-adjusted meal response.
Within-participant covariate-adjusted linear mixed models were used to quantify participant by-condition and genotype-by-condition interactions. Results: The meal suppressed acylated
ghrelin and appetite perceptions (standardized effect sizes (ES): 0.18-4.26) and elevated total
PYY, insulin and glucose (ES: 1.96-21.60). For all variables, SD of change scores was
greater in the meal versus control conditions. Moderate-to-large positive correlations were
observed between the two replicates of control-adjusted meal responses for all variables
(r=0.44-0.86, P≤0.070). Participant-by-condition interactions were present for all variables
(P≤0.056). FTO genotype-by-condition interactions were not significant (P≥0.19) and
treatment effect differences between genotype groups were small (ES≤0.27) for all appetite
parameters. Conclusions: Reproducibility of postprandial appetite responses is generally
good. True interindividual variability is present beyond any random within-subject variation
in healthy men but is not moderated by the FTO genotype. These findings highlight the
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importance of exploring individual differences in appetite for the prevention and/or treatment
of obesity. Clinical trial registry number: NCT03771690 (ClinicalTrials.gov)
Structural insights into the function of the catalytically active human Taspase1
19 pags., 7 figs., 2 tabs.Taspase1 is an Ntn-hydrolase overexpressed in primary human cancers, coordinating cancer cell proliferation, invasion, and metastasis. Loss of Taspase1 activity disrupts proliferation of human cancer cells in vitro and in mouse models of glioblastoma. Taspase1 is synthesized as an inactive proenzyme, becoming active upon intramolecular cleavage. The activation process changes the conformation of a long fragment at the C-terminus of the α subunit, for which no full-length structural information exists and whose function is poorly understood. We present a cloning strategy to generate a circularly permuted form of Taspase1 to determine the crystallographic structure of active Taspase1. We discovered that this region forms a long helix and is indispensable for the catalytic activity of Taspase1. Our study highlights the importance of this element for the enzymatic activity of Ntn-hydrolases, suggesting that it could be a potential target for the design of inhibitors with potential to be developed into anticancer therapeutics.This project has been funded in whole with Federal funds from the National Cancer Institute (NCI), National Institutes of Health (NIH), under Chemical Biology Consortium contract no. HHSN261200800001E
Football Banning Orders: The Highly Effective Cornerstone of a Preventative Strategy?
The chapter examines the development, use and effectiveness of football banning orders in the UK, comparing their use in England to address issues of football 'hooliganism' with their distinct evolution in Scotland to address concerns around sectarian disorder
Idiopathic interstitial pneumonia: Do community and academic physicians agree on diagnosis?
Rationale: Treatment and prognoses of diffuse parenchymal lung
diseases (DPLDs) varies by diagnosis. Obtaining a uniform diagnosis
among observers is difficult.
Objectives: Evaluate diagnostic agreement between academic and
community-based physicians for patients with DPLDs, and determine
if an interactive approach between clinicians, radiologists,
and pathologists improved diagnostic agreement in community
and academic centers.
Methods: Retrospective review of 39 patients with DPLD. A total of
19 participants reviewed cases at 2 community locations and 1
academic location. Information from the history, physical examination,
pulmonary function testing, high-resolution computed tomography,
and surgical lung biopsy was collected. Data were presented
in the same sequential fashion to three groups of physicians on
separate days.
Measurements and Main Results: Each observer’s diagnosis was coded
into one of eight categories. A statistic allowing formultiple raters
was used to assess agreement in diagnosis. Interactions between
clinicians, radiologists, and pathologists improved interobserver
agreement at both community and academic sites; however, final
agreement was better within academic centers (Kappa= 0.55–0.71) than
within community centers (Kappa=0.32–0.44). Clinically significant
disagreement was present between academic and communitybased
physicians (Kappa=0.11–0.56). Community physicians were more
likely to assign a final diagnosis of idiopathic pulmonary fibrosis
compared with academic physicians.
Conclusions: Significant disagreement exists in the diagnosis of
DPLD between physicians based in communities compared with
those in academic centers. Wherever possible, patients should be
referred to centers with expertise in diffuse parenchymal lung disorders
to help clarify the diagnosis and provide suggestions regarding
treatment options.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91941/1/2007 AJRCCM Idiopathic interstitial pneumonia - Do community and academic physicians agree on diagnosis.pd
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