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Abstract

Cast axes are one of the most numerous categories of bronze products from earlier phases of the Bronze Age found in Poland. They had multiple applications since they were not only used objects such as tools or weapons but also played the prestigious and cult roles. Investigations of the selected axes from the bronze products treasure of the Bronze Age, found in the territory of Poland, are presented in the hereby paper. The holder of these findings is the State Archaeological Museum in Warsaw. Metallurgical investigations of axes with bushing were performed in respect of the casting technology and quality of obtained castings. Macroscopic observations allowed to document the remains of the gating system and to assess the range and kind of casting defects. Light microscopy revealed the microstructure character of these relicts. The chemical composition was determined by means of the X-ray fluorescence method with energy dispersion (ED-XRF) and by the scanning electron microscopy with X-ray energy dispersion analysis in micro-areas (SEM-EDS). The shape and dimensions of cores, reproducing inner parts of axes were identified on the basis of the X-ray tomography images. Studies reconstructed production technology of the mould with gating system, determined chemical composition of the applied alloys and casting structures as well as revealed the casting defects being the result of construction and usage of moulds and cores.
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Abstract

The casting workshop was discovered with numerous artifacts, confirming the existence of the manufacturing process of metal ornaments using ceramic molds and investment casting technology in Lower Silesia (Poland) in 7-6 BC. The research has yielded significant technological information about the bronze casting field, especially the alloys that were used and the artifacts that were made from them. Based on the analyses, the model alloys were experimentally reconstructed. Taking advantage of the computer-modeling method, a geometric visualization of the bronze bracelets was performed; subsequently, we simulated pouring liquid metal in the ceramic molds and observed the alloy solidification. These steps made it possible to better understand the casting processes from the perspective of the mold technology as well as the melting and casting of alloys.
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Abstract

B a c k g r o u n d: A novel paradigm of diastolic heart failure with preserved ejection fraction (HFpEF) proposed the induction of coronary microvascular dysfunction by HFpEF comorbidities via a systemic pro-infl ammatory state and associated oxidative stress. Th e consequent nitric oxide deficiency would increase diastolic tension and favor fi brosis of adjacent myocardium, which implies not only left ventricular (LV), but all-chamber myocardial stiff ening. Our aim was to assess relations between low-grade chronic systemic infl ammation and left atrial (LA) pressure-volume relations in real-world HFpEF patients. Me t h o d s: We retrospectively analyzed medical records of 60 clinically stable HpEFF patients in sinus rhythm with assayed high-sensitive C-reactive protein (CRP) during the index hospitalization. Subjects with CRP >10 mg/L or coexistent diseases, including coronary artery disease, were excluded. LV and LA diameters and mitral E/E’ ratio (an index of LA pressure) were extracted from routine echocardiographic 46 Cyrus M. Sani, Elahn P.L. Pogue, et al. records. A surrogate measure of LA stiff ness was computed as the averaged mitral E/e’ ratio divided by LA diameter. R e s u l t s: With ascending CRP tertiles, we observed trends for elevated mitral E/e’ ratio (p <0.001), increased relative LV wall thickness (p = 0.01) and higher NYHA functional class (p = 0.02). Th e LA stiffness estimate and log-transformed CRP levels (log-CRP) were interrelated (r = 0.38, p = 0.003). On multivariate analysis, the LA stiff ness index was independently associated with log-CRP (β ± SEM: 0.21 ± 0.07, p = 0.007) and age (β ± SEM: 0.16 ± 0.07, p = 0.03), which was maintained upon adjustment for LV mass index and relative LV wall thickness. C o n c l u s i o n s: Low-grade chronic infl ammation may contribute to LA stiff ening additively to age and regardless of the magnitude of associated LV hypertrophy and concentricity. LA stiff ening can exacerbate symptoms of congestion in HFpEF jointly with LV remodeling.
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