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This article explores the potential of kernel-based techniques for discriminating on-specification and off-specification batch runs, combining kernel-partial least squares discriminant analysis and three common approaches to analyze batch data by means of bilinear models: landmark features extraction, batchwise unfolding, and variablewise unfolding. Gower s idea of pseudo-sample projection is exploited to recover the contribution of the initial variables to the final model and visualize those having the highest discriminant power. The results show that the proposed approach provides an efficient fault discrimination and enables a correct identification of the discriminant variables in the considered case studies.

Background: Multipoint left ventricular (LV) pacing (MultiPoint™ Pacing [MPP], Abbott, Sylmar, CA, USA) improves the response rate to cardiac resynchronization therapy (CRT). We evaluated the feasibility of noninvasive radial artery tonometry (RAT) to characterize arterial pressure morphology changes (pre-ejection period [PEP] and ejection duration [ED]) between conventional CRT and MPP pacing interventions. Methods: Patients with a MPP-enabled CRT device (Quadra Assura MP™, Abbott) underwent noninvasive RAT assessment (SphygmoCor CVMS, AtCor Medical Inc., Itasca, IL, USA) at 3–6 months after implantation. A pacing protocol was performed in a randomized order including one optimized conventional biventricular CRT (CONV) configuration using the distal electrode and five MPP configurations. The PEP, ED, and PEP/ED ratio were determined for each intervention from the RAT pressure waveform and electrocardiogram. Results: Pressure waveforms were successfully recorded in 19 patients (89% male, QRS 147 ± 16ms, 63% ischemic). In 17/19 (89%) patients, at least one MPP intervention resulted in improved PEP, ED, and PEP/ED compared to CONV. The MPP intervention with greatest separation of LV cathodes and minimum intra-LV delay significantly improved PEP (mean PEP –15 ± 33%vs –8 ± 32% [CONV], P=0.04) and ED (mean ED +8 ± 8% [MPP] vs +4 ± 7% [CONV], P=0.02), and PEP/ED (–0.07 ± 0.14 [MPP] vs –0.04 ± 0.13 [CONV], P=0.02) compared with CONV. Conclusions: Noninvasive RAT efficiently characterizes changes in PEP and ED between CONV and MPP interventions. MPP configurations using the widest separation among LV cathodes and minimum intra-LV delay may significantly improve RAT-derived parameters as compared to conventional CRT.

In this research, we studied the compositional, crystallographic and microstructural properties of a series of incuse silver didrachmae stemming from the Achaean colonies of Metapontum and Caulonia. In this paper, we address the following points: (i) the metal sources, (ii) the fabrication process and (iii) degradation phenomena, such as incrustation and embrittlement. In this investigation, we employed energy-dispersive X-ray fluorescence spectroscopy, X-ray diffractometry, and scanning electron and optical microscopies. The patina is mainly composed of chlorargirite. The coins consist of a silver-rich alloy containing ∼ 1% of Au and Cu. Metallographic and local compositional analyses revealed a complex scenario of inclusions. In one instance, unalloyed copper grains, two-phase copper/bismuth globuli and high-bismuth filaments were observed. In other cases, globular Cu 2 S (chalcocite) inclusions were noticed. The presence of SiO 2 and iron oxide inclusions is ubiquitous in these samples. Distorted twin lines and strain lines can be detected, denoting work-hardening of recrystailized flans. Grain polygonalization can occasionally be noticed, hinting at secondary recrystallization processes. The irregularly shaped iron oxide particles often act as crack initiation sites: Fracture facets are generally intergranular. On some areas, intergranular decohesion is also observed. Open cracks sometimes contain AgCl. The strain lines that can be noticed on the fracture surfaces indicate work-hardening and residual microstructural deformation. Information regarding inclusions and the presence of significant amounts of gold can he tentatively used to address provenancing and fabrication issues.