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The structures of glasses in the lithium–bismuth orthoborate composition range deviate significantly from the short‐range order structure of the two crystalline end‐members. Although binary Li3BO3 and BiBO3 are solely of comprised trigonal orthoborate anions, all glasses formed by their combination contain four‐coordinated borate tetrahedra. We analyze the structure of (75−1.5x)Li2O–xBi2O3–(25+0.5x)B2O3 glasses in increments of x = 5, with 11B magic‐angle spinning nuclear magnetic resonance (NMR), infrared (IR), and Raman spectroscopy. For the full series, the oxygen‐to‐boron ratio remains constant at O/B = 3:1. NMR quantifies an increase in the fraction of tetrahedral boron with increasing bismuth oxide content. Evolution of the mid‐IR profile suggests multiple types of tetrahedral boron sites. Raman spectroscopy reveals that Bi2O3 tends to cluster within the lithium borate matrix when initially introduced and that this behavior transforms into a bismuthate network with increasing bismuth oxide content. In all cases, mixed Bi–O–B linkages are observed. The dual role of bismuth as network modifier and network former is likewise observed in the far IR. The glass transition temperature continuously increases with bismuth oxide content; however, the glass stability displays a maximum in the multicomponent glass of x = 40. [ABSTRACT FROM AUTHOR]

Background: Initial clinical applications have shown that US elastography might be able to distinguish tissues because of their specific consistency. Objective: (1) To investigate the feasibility of EUS elastography of the pancreas and (2) to describe elastographic patterns of the normal pancreas and the pancreas affected by inflammatory or focal disease. Design: Prospective single-center study. Setting: Academic center of the University of Witten/Herdecke. Patients: Twenty patients with normal pancreas, 20 patients with chronic pancreatitis, and 33 patients with focal pancreatic lesion, histologically later proven in 32 of these 33 cases. Interventions: Commercially available US equipment was used. The elasticity of tissue was reconstructed in real time within a sample area and was translated into a color scale imaging relative tissue elasticity within this area. Representative loops of at least 20 seconds were recorded regarding each region of interest. Results: Adequate elastographic recordings could be obtained in all 73 patients. Patients with hypoechoic and intermediately echogenic normal pancreas revealed a relatively homogeneous elastographic pattern. Thirty-one focal lesions, including 30 neoplasms and most of the chronically inflamed pancreata had a honeycomb pattern dominated by hard strands. This pattern showed analogies to the histologic structure of 10 resected tumors. Other patients with chronic pancreatitis and those with hyperechoic healthy pancreas had miscellaneous elastographic appearances. Conclusions: EUS elastography of the pancreas is feasible and produces plausible results. The examination of homogeneous tissue is impaired by the relative scale used. Chronic pancreatitis and hard tumors cannot be distinguished by elastography, probably because of their similar fibrous structure. [Copyright &y& Elsevier]

Aim: To investigate the diagnostic significance of transient elastography (TE) in a daily routine clinical setting in comparison to clinical signs, laboratory parameters and ultrasound., Methods: TE, ultrasound, laboratory parameters and cutaneous liver signs were assessed in 291 consecutive patients with chronic liver disease of various aetiologies who underwent liver biopsy in daily routine., Results: Sensitivity of TE for the detection of liver cirrhosis was 90.4%, compared to 80.1% for ultrasound, 58.0% for platelet count and 45.1% for cutaneous liver signs (P < 0.0001 for comparisons with histology). AUROC for TE was 0.760 (95%CI: 0.694-0.825). Combination of TE with ultrasound increased sensitivity to 96.1% and AUROC to 0.825 (95%CI: 0.768-0.882). TE correlated with laboratory parameters of cirrhosis progression like albumin (r = -0.43), prothrombin time (r = -0.44), and bilirubin (r = 0.34; P < 0.001 for each). Particularly, in patients with Child Pugh score A or normal platelet count TE improved sensitivity for the detection of liver cirrhosis compared to ultrasound by 14.1% (P < 0.04) and 16.3% (P < 0.02), respectively., Conclusion: Transient elastography is superior to routine diagnostic tests allowing detection of liver cirrhosis in additional 10%-16% of patients with chronic liver disease that would have been missed by clinical examinations.