Aircraft system modeling error and control error

A method for modeling error-driven adaptive control of an aircraft. Normal aircraft plant dynamics is modeled, using an original plant description in which a controller responds to a tracking error e(k) to drive the component to a normal reference value according to an asymptote curve. Where the system senses that (1) at least one aircraft plant component is experiencing an excursion and (2) the return of this component value toward its reference value is not proceeding according to the expected controller characteristics, neural network (NN) modeling of aircraft plant operation may be changed. However, if (1) is satisfied but the error component is returning toward its reference value according to expected controller characteristics, the NN will continue to model operation of the aircraft plant according to an original description

A robust sequential hypothesis testing method for brake squeal localisation

This contribution deals with the in situ detection and localisation of brake squeal in an automobile. As brake squeal is emitted from regions known a priori, i.e., near the wheels, the localisation is treated as a hypothesis testing problem. Distributed microphone arrays, situated under the automobile, are used to capture the directional properties of the sound field generated by a squealing brake. The spatial characteristics of the sampled sound field is then used to formulate the hypothesis tests. However, in contrast to standard hypothesis testing approaches of this kind, the propagation environment is complex and time-varying. Coupled with inaccuracies in the knowledge of the sensor and source positions as well as sensor gain mismatches, modelling the sound field is difficult and standard approaches fail in this case. A previously proposed approach implicitly tried to account for such incomplete system knowledge and was based on ad hoc likelihood formulations. The current paper builds upon this approach and proposes a second approach, based on more solid theoretical foundations, that can systematically account for the model uncertainties. Results from tests in a real setting show that the proposed approach is more consistent than the prior state-of-the-art. In both approaches, the tasks of detection and localisation are decoupled for complexity reasons. The localisation (hypothesis testing) is subject to a prior detection of brake squeal and identification of the squeal frequencies. The approaches used for the detection and identification of squeal frequencies are also presented. The paper, further, briefly addresses some practical issues related to array design and placement. (C) 2019 Author(s)

Genetic Risk and Atrial Fibrillation in Patients with Heart Failure

Aims: To study the association between an atrial fibrillation (AF) genetic risk score with prevalent AF and all-cause mortality in patients with heart failure. Methods and results: An AF genetic risk score was calculated in 3759 European ancestry individuals (1783 with sinus rhythm, 1976 with AF) from the BIOlogy Study to TAilored Treatment in Chronic Heart Failure (BIOSTAT-CHF) by summing 97 single nucleotide polymorphism (SNP) alleles (ranging from 0–2) weighted by the natural logarithm of the relative SNP risk from the latest AF genome-wide association study. Further, we assessed AF risk variance explained by additive SNP variation, and performance of clinical or genetic risk factors, and the combination in classifying AF prevalence. AF was classified as AF or atrial flutter (AFL) at baseline electrocardiogram and/or a history of AF or AFL. The genetic risk score was associated with AF after multivariable adjustment. Odds ratio for AF prevalence per 1-unit increase genetic risk score was 2.12 (95% confidence interval 1.84–2.45, P = 2.15 × 10−24) in the total cohort, 2.08 (1.72–2.50, P = 1.30 × 10−14) in heart failure with reduced ejection fraction (HFrEF) and 2.02 (1.37–2.99, P = 4.37 × 10−4) in heart failure with preserved ejection fraction (HFpEF). AF-associated loci explained 22.9% of overall AF SNP heritability. Addition of the genetic risk score to clinical risk factors increased the C-index by 2.2% to 0.721. Conclusions: The AF genetic risk score was associated with increased AF prevalence in HFrEF and HFpEF. Genetic variation accounted for 22.9% of overall AF SNP heritability. Addition of genetic risk to clinical risk improved model performance in classifying AF prevalence

Quality of life in men and women with heart failure:association with outcome, and comparison between the Kansas City Cardiomyopathy Questionnaire and the EuroQol 5 dimensions questionnaire

Aims: We sought to analyse quality of life (QoL) measures derived from two questionnaires widely used in clinical trials, the Kansas City Cardiomyopathy Questionnaire (KCCQ) and the EuroQoL 5 dimensions (EQ-5D), and to compare their prognostic value in men and women with heart failure and reduced ejection fraction (HFrEF).Methods and results: From the BIOlogy Study to TAilored Treatment in Chronic Heart Failure (BIOSTAT-CHF) we compared KCCQ and EQ-5D at baseline and after 9 months in 1276 men and 373 women with new-onset or worsening symptoms of HFrEF, who were sub-optimally treated and in whom there was an anticipated up-titration of guideline-derived medical therapies. Women had significantly worse baseline QoL (median) as compared with men, both when assessed with KCCQ overall score (KCCQ-OS, 44 vs. 53, P &lt; 0.001) and EQ-5D utility score (0.62 vs. 0.73, P &lt; 0.001). QoL improved equally in women and men at follow-up. All summary measures of QoL were independently associated with all-cause mortality, with KCCQ-OS showing the most remarkable association with mortality up to 1 year compared to the EQ-5D scores (C-statistic 0.650 for KCCQ-OS vs. 0.633 and 0.599 for EQ-5D utility score and EQ-5D visual analogue scale, respectively). QoL was associated with all outcomes analysed, both in men and women (all P for interaction with sex &gt;0.2).Conclusion: Amongst patients with HFrEF, women reported significantly worse QoL than men. QoL was independently associated with subsequent outcome, similarly in men and women. The KCCQ in general, and the KCCQ-OS in particular, showed the strongest independent association with outcome.</p

Quality of life in men and women with heart failure:association with outcome, and comparison between the Kansas City Cardiomyopathy questionnaire and the EuroQol 5 dimensions questionnaire

Aims We sought to analyse quality of life (QoL) measures derived from two questionnaires widely used in clinical trials, the Kansas City Cardiomyopathy Questionnaire (KCCQ) and the EuroQoL 5 dimensions (EQ-5D), and to compare their prognostic value in men and women with heart failure and reduced ejection fraction (HFrEF). Methods and results From the BIOlogy Study to TAilored Treatment in Chronic Heart Failure (BIOSTAT-CHF) we compared KCCQ and EQ-5D at baseline and after 9 months in 1276 men and 373 women with new-onset or worsening symptoms of HFrEF, who were sub-optimally treated and in whom there was an anticipated up-titration of guideline-derived medical therapies. Women had significantly worse baseline QoL (median) as compared with men, both when assessed with KCCQ overall score (KCCQ-OS, 44 vs. 53, P 0.2). Conclusion Amongst patients with HFrEF, women reported significantly worse QoL than men. QoL was independently associated with subsequent outcome, similarly in men and women. The KCCQ in general, and the KCCQ-OS in particular, showed the strongest independent association with outcome.publishedVersio

Investigation of photoplethysmographic signals and blood oxygen saturation values obtained from human splanchnic organs using a fiber optic sensor

Objective A reliable, continuous method of monitoring splanchnic organ oxygen saturation could allow for the early detection of malperfusion, and may prevent the onset of multiple organ failure. Current monitoring techniques have not been widely accepted in critical care monitoring. As a preliminary to developing a continuous indwelling device, this study evaluates a new handheld fiber optic photoplethysmographic (PPG) sensor for estimating the blood oxygen saturation (SpO2) of splanchnic organs during surgery. Methods A fiber optic splanchnic PPG sensor, instrumentation system and virtual instrument were developed to facilitate PPG and SpO2 measurement from splanchnic organs. Following Local Research Ethics Committee approval, the sensor was evaluated on seventeen ASA 1 and 2 patients undergoing open laparotomy. PPG signals were obtained from the large bowel, small bowel, liver and stomach. Simultaneous PPG signals from the finger were also obtained using an identical fiber optic sensor. Results Good quality PPG signals with high signal-to-noise (SNR) ratios were obtained from all splanchnic sites under investigation. Analysis of the ac and dc amplitudes of the red and infrared PPG signals showed there to be a statistically significant difference between PPG signals obtained from splanchnic organs with those obtained from the finger (using fiber optic sensors). Estimated SpO2 values from the splanchnic organs show good agreement with those obtained from the finger using both a fiber optic sensor and a commercial device. Furthermore, the results of a Bland and Altman analysis indicate that fiber optic splanchnic pulse oximetry, particularly of the bowel, may provide a suitable method for monitoring splanchnic organ perfusion. Conclusion The evaluation of a new fiber optic sensor on anaesthetized patients undergoing laparotomy demonstrated that good quality PPG signals and SpO2 estimates can be obtained from splanchnic organs. Such a sensor may provide a useful tool for the intraoperative assessment of splanchnic perfusion

Albuminuria as a marker of systemic congestion in patients with heart failure

International audienceAbstract Aims Albuminuria is common in patients with heart failure and associated with worse outcomes. The underlying pathophysiological mechanism of albuminuria in heart failure is still incompletely understood. The association of clinical characteristics and biomarker profile with albuminuria in patients with heart failure with both reduced and preserved ejection fractions were evaluated. Methods and results Two thousand three hundred and fifteen patients included in the index cohort of BIOSTAT-CHF were evaluated and findings were validated in the independent BIOSTAT-CHF validation cohort (1431 patients). Micro-albuminuria and macro-albuminuria were defined as urinary albumin–creatinine ratio (UACR) &gt;30 mg/gCr and &gt;300 mg/gCr in spot urines, respectively. The prevalence of micro- and macro-albuminuria was 35.4% and 10.0%, respectively. Patients with albuminuria had more severe heart failure, as indicated by inclusion during admission, higher New York Heart Association functional class, more clinical signs and symptoms of congestion, and higher concentrations of biomarkers related to congestion, such as biologically active adrenomedullin, cancer antigen 125, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) (all P &lt; 0.001). The presence of albuminuria was associated with increased risk of mortality and heart failure (re)hospitalization in both cohorts. The strongest independent association with log UACR was found for log NT-proBNP (standardized regression coefficient 0.438, 95% confidence interval 0.35–0.53, P &lt; 0.001). Hierarchical clustering analysis demonstrated that UACR clusters with markers of congestion and less with indices of renal function. The validation cohort yielded similar findings. Conclusion In patients with new-onset or worsening heart failure, albuminuria is consistently associated with clinical, echocardiographic, and circulating biomarkers of congestion

Fifteen new risk loci for coronary artery disease highlight arterial-wall-specific mechanisms

Coronary artery disease (CAD) is a leading cause of morbidity and mortality worldwide. Although 58 genomic regions have been associated with CAD thus far, most of the heritability is unexplained, indicating that additional susceptibility loci await identification. An efficient discovery strategy may be larger-scale evaluation of promising associations suggested by genome-wide association studies (GWAS). Hence, we genotyped 56,309 participants using a targeted gene array derived from earlier GWAS results and performed meta-analysis of results with 194,427 participants previously genotyped, totaling 88,192 CAD cases and 162,544 controls. We identified 25 new SNP-CAD associations (P &lt; 5 × 10(-8), in fixed-effects meta-analysis) from 15 genomic regions, including SNPs in or near genes involved in cellular adhesion, leukocyte migration and atherosclerosis (PECAM1, rs1867624), coagulation and inflammation (PROCR, rs867186 (p.Ser219Gly)) and vascular smooth muscle cell differentiation (LMOD1, rs2820315). Correlation of these regions with cell-type-specific gene expression and plasma protein levels sheds light on potential disease mechanisms

Distinct pathophysiological pathways in women and men with heart failure

Aims: Clinical differences between women and men have been described in heart failure (HF). However, less is known about the underlying pathophysiological mechanisms. In this study, we compared multiple circulating biomarkers to gain better insights into differential HF pathophysiology between women and men. Methods and Results: In 537 women and 1485 men with HF, we compared differential expression of a panel of 363 biomarkers. Then, we performed a pathway over-representation analysis to identify differential biological pathways in women and men. Findings were validated in an independent HF cohort (575 women, 1123 men). In both cohorts, women were older and had higher ejection fraction (LVEF). In the index and validation cohorts respectively, we found 14/363 and 12/363 biomarkers that were relatively up-regulated in women, while 21/363 and 14/363 were up-regulated in men. In both cohorts, the strongest up-regulated biomarkers in women were leptin and fatty acid binding protein-4, compared to matrix metalloproteinase-3 in men. Similar findings were replicated in a subset of patients from both cohorts matched by age and LVEF. Pathway over-representation analysis revealed increased activity of pathways associated with lipid metabolism in women, and neuroinflammatory response in men (all p &lt; 0.0001). Conclusion: In two independent cohorts of HF patients, biomarkers associated with lipid metabolic pathways were observed in women, while biomarkers associated with neuro-inflammatory response were more active in men. Differences in inflammatory and metabolic pathways may contribute to sex differences in clinical phenotype observed in HF, and provide useful insights towards development of tailored HF therapies