Design of the Model for the On-line Control of the AWJ Technology based on Neural Networks

The paper focuses on the problem of prediction of surface roughness in AWJ process and contribute to the online monitoring of the hydro-abrasive material disintegration process and its possible control. The main scope of the paper is to contribute to the usage of an artificial neural network as a decisive part in the surface roughness prediction and to outline a suitable online control mechanism. In paper a series of experiments were conducted to predict surface roughness and to use phenomena like acoustic emission and vibrations that accompany the cutting process to use in a possible process control. The model of artificial neural network was created in the MATLAB environment. In total, 150 configurations of multilayer perceptron with different configurations of numbers of neurons in hidden layers were developed. Two training functions, the Bayesian regularization and the Levenberg–Marquardt algorithm, were used during the network training. The results of the realized experiment have shown that the network with feedforward topology is able to predict correct value of the profile roughness parameter

Clinical effect of sex-specific cutoff values of high-sensitivity cardiac troponin T in suspected myocardial infarction

It is currently unknown whether the uniform (universal clinical practice for more than 2 decades) or 2 sex-specific cutoff levels are preferable when using high-sensitivity cardiac troponin T (hs-cTnT) levels in the diagnosis of acute myocardial infarction (AMI).To improve the management of suspected AMI in women by exploring sex-specific vs uniform cutoff levels for hs-cTnT.In an ongoing prospective, diagnostic, multicenter study conducted at 9 emergency departments, the present study evaluated patients enrolled from April 21, 2006, through June 5, 2013. The participants included 2734 adults presenting with suspected AMI. Duration of follow-up was 2 years, and data analysis occurred from June 5 to December 21, 2015.The final diagnosis was centrally adjudicated by 2 independent cardiologists using all available information, including measurements of serial hs-cTnT blood concentrations twice: once using the uniform 99th percentile cutoff value level of 14 ng/L and once using sex-specific 99th percentile levels of hs-cTnT (women, 9 ng/L; men, 15.5 ng/L).Diagnostic reclassification in women and men using sex-specific vs the uniform cutoff level in the diagnosis of AMI.Of the 2734 participants, 876 women (32%) and 1858 men (68%) were included. Median (interquartile range) age was 68 (55-77) and 59 (48-71) years, respectively. With the use of the uniform cutoff value, 127 women (14.5%) and 345 men (18.6%) received a final diagnosis of AMI. Among these, at emergency department presentation, levels of hs-cTnT were already above the uniform cutoff value in 427 patients (sensitivity, 91.3% [95% CI, 85%-95.6%] in women vs 90.7% [95% CI, 87.1%-93.5% in men]; specificity, 79.2% [95% CI, 76.1%-82.1%] in women vs 78.5% [95% CI, 76.4%-80.6%] in men). After readjudication using sex-specific 99th percentile levels, diagnostic reclassification regarding AMI occurred in only 3 patients: 0.11% (95% CI, 0.02-0.32) of all patients and 0.6% (95% CI, 0.13-1.85) of patients with AMI. The diagnosis in 2 women was upgraded from unstable angina to AMI, and the diagnosis in 1 man was downgraded from AMI to unstable angina. These diagnostic results were confirmed when using 2 alternative pairs of uniform and sex-specific cutoff values.The uniform 99th percentile should remain the standard of care when using hs-cTnT levels for the diagnosis of AMI

Diagnosis of acute myocardial infarction in the presence of left bundle branch block

Objective Patients with suspected acute myocardial infarction (AMI) in the setting of left bundle branch block (LBBB) present an important diagnostic and therapeutic challenge to the clinician. Methods We prospectively evaluated the incidence of AMI and diagnostic performance of specific ECG and high-sensitivity cardiac troponin (hs-cTn) criteria in patients presenting with chest discomfort to 26 emergency departments in three international, prospective, diagnostic studies. The final diagnosis of AMI was centrally adjudicated by two independent cardiologists according to the universal definition of myocardial infarction. Results Among 8830 patients, LBBB was present in 247 (2.8%). AMI was the final diagnosis in 30% of patients with LBBB, with similar incidence in those with known LBBB versus those with presumably new LBBB (29% vs 35%, p=0.42). ECG criteria had low sensitivity (1%-12%) but high specificity (95%-100%) for AMI. The diagnostic accuracy as quantified by the receiver operating characteristics (ROC) curve of hs-cTnT and hs-cTnI concentrations at presentation (area under the ROC curve (AUC) 0.91, 95% CI 0.85 to 0.96 and AUC 0.89, 95% CI 0.83 to 0.95), as well as that of their 0/1-hour and 0/2-hour changes, was very high. A diagnostic algorithm combining ECG criteria with hs-cTnT/I concentrations and their absolute changes at 1 hour or 2 hours derived in cohort 1 (45 of 45(100%) patients with AMI correctly identified) showed high efficacy and accuracy when externally validated in cohorts 2 and 3 (28 of 29 patients, 97%). Conclusion Most patients presenting with suspected AMI and LBBB will be found to have diagnoses other than AMI. Combining ECG criteria with hs-cTnT/I testing at 0/1 hour or 0/2 hours allows early and accurate diagnosis of AMI in LBBB. Trial registration number APACE: NCT00470587; ADAPT: ACTRN12611001069943; TRAPID-AMI: RD001107;Results

Diagnosis of acute myocardial infarction in the presence of left bundle branch block

Objective Patients with suspected acute myocardial infarction (AMI) in the setting of left bundle branch block (LBBB) present an important diagnostic and therapeutic challenge to the clinician. Methods We prospectively evaluated the incidence of AMI and diagnostic performance of specific ECG and high-sensitivity cardiac troponin (hs-cTn) criteria in patients presenting with chest discomfort to 26 emergency departments in three international, prospective, diagnostic studies. The final diagnosis of AMI was centrally adjudicated by two independent cardiologists according to the universal definition of myocardial infarction. Results Among 8830 patients, LBBB was present in 247 (2.8%). AMI was the final diagnosis in 30% of patients with LBBB, with similar incidence in those with known LBBB versus those with presumably new LBBB (29% vs 35%, p=0.42). ECG criteria had low sensitivity (1%-12%) but high specificity (95%-100%) for AMI. The diagnostic accuracy as quantified by the receiver operating characteristics (ROC) curve of hs-cTnT and hs-cTnI concentrations at presentation (area under the ROC curve (AUC) 0.91, 95% CI 0.85 to 0.96 and AUC 0.89, 95% CI 0.83 to 0.95), as well as that of their 0/1-hour and 0/2-hour changes, was very high. A diagnostic algorithm combining ECG criteria with hs-cTnT/I concentrations and their absolute changes at 1 hour or 2 hours derived in cohort 1 (45 of 45(100%) patients with AMI correctly identified) showed high efficacy and accuracy when externally validated in cohorts 2 and 3 (28 of 29 patients, 97%). Conclusion Most patients presenting with suspected AMI and LBBB will be found to have diagnoses other than AMI. Combining ECG criteria with hs-cTnT/I testing at 0/1 hour or 0/2 hours allows early and accurate diagnosis of AMI in LBBB. Trial registration number APACE: NCT00470587; ADAPT: ACTRN12611001069943; TRAPID-AMI: RD001107;Results.</p

Impact of age on the performance of the ESC 0/1h-algorithms for early diagnosis of myocardial infarction

Aims We aimed to evaluate the impact of age on the performance of the European Society of Cardiology (ESC) 0/1halgorithms and to derive and externally validate alternative cut-offs specific to older patients. Methods and results We prospectively enrolled patients presenting to the emergency department (ED) with symptoms suggestive of acute myocardial infarction in three large diagnostic studies. Final diagnoses were adjudicated by two independent cardiologists. High-sensitivity cardiac troponin (hs-cTn) T and I concentrations were measured at presentation and after 1 h. Patients were stratified according to age [<55 years (young), ≥55 to <70 years (middle-age), ≥70 years (old)]. Rule-out safety of the ESC hs-cTnT 0/1h-algorithm was very high in all age-strata: sensitivity 100% [95% confidence interval (95% CI) 94.9-100] in young, 99.3% (95% CI 96.0-99.9) in middle-age, and 99.3% (95% CI 97.5- 99.8) in old patients. Accuracy of rule-in decreased with age: specificity 97.0% (95% CI 95.8-97.9) in young, 96.1% (95% CI 94.5-97.2) in middle-age, and 92.7% (95% CI 90.7-94.3) in older patients. Triage efficacy decreased with increasing age (young 93%, middle-age 80%, old 55%, P < 0.001). Similar results were found for the ESC hs-cTnT 0/1h-algorithm. Alternative, slightly higher cut-off concentrations optimized for older patients maintained very high safety of rule-out, increased specificity of rule-in (P < 0.01), reduced overall efficacy for hs-cTnT (P < 0.01), while maintaining efficacy for hs-cTnI. Findings were confirmed in two validation cohorts (n = 2767). Conclusion While safety of the ESC 0/1h-algorithms remained very high, increasing age significantly reduced overall efficacy and the accuracy of rule-in. Alternative slightly higher cut-off concentrations may be considered for older patients, particularly if using hs-cTnI