Evaluating the effect of roasting on coffee lipids using a hybrid targeted-untargeted NMR approach in combination with MRI.

An integrated targeted-untargeted 1H and 13C Nuclear Magnetic Resonance (NMR) analysis was applied to determine the impact of roasting on coffee lipids. For targeted analysis, both an internal standard (IS) method, as well as the ERETIC2 tool based on PULCON (Pulse Length-based Concentration determination), were used for quantitation. PULCON allows for quantitative analysis without sample contamination with an IS and was found to be in very good agreement with the traditional IS approach as indicated by a systematic Bland-Altman comparison study. For the untargeted analysis, NMR was coupled with multivariate statistical analysis (MVSA), namely Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), and Orthogonal Projection to Latent Structures Discriminant Analysis (OPLS-DA). 13C NMR spectra were acquired using a z-stored spin-echo sequence to achieve higher spectral quality, which is important for both targeted and untargeted analysis. Results showed that roasting has a clear effect on coffee lipids, with diterpenes, oxidation/hydrolysis products and unsaturated fatty acid chains being the most significant markers. In addition, the application of MRI indicated important morphological alterations in bean structure and lipid migration from the endosperm to the surface of the coffee bean.

High throughput crystal structure and composition mapping of crystalline nanoprecipitates in alloys by transmission Kikuchi diffraction and analytical electron microscopy.

Statistically significant crystal structure and composition identification of nanocrystalline features such as nanoparticles/nanoprecipitates in materials chemistry and alloy designing using electron microscopy remains a grand challenge. In this paper, we reveal that differing crystallographic phases of nanoprecipitates in alloys can be mapped with unprecedented statistics using transmission Kikuchi diffraction (TKD), on typical carbon-based electron-transparent samples. Using a case of multiphase, multicomponent nanoprecipitates extracted from an improved version of 9% chromium Eurofer-97 reduced-activation ferritic-martensitic steel we show that TKD successfully identified more than thousand M23C6, MX, M7C3, and M2X (M=Fe, Cr, W, V, Ta; X = C, N) nanoprecipitates in a single scan, something that is currently unachievable using a transmission electron microscope (TEM) without incorporating a precision electron diffraction (PED) system. Precipitates as small as ∼20-25 nm were successfully phase identified by TKD. We verified the TKD phase identification using high-resolution transmission electron microscopy (HRTEM) and convergent beam electron diffraction (CBED) pattern analysis of a few precipitates that were identified by TKD on same sample. TKD study was combined with state-of-art analytical scanning transmission electron microscopy (STEM)-energy dispersive X-ray (EDX) spectroscopy and multivariate statistical analysis (MVSA) which provided the complete crystal structure and distinct chemistries of the precipitates in the steel in a high throughput automated way. This technique should be applicable to characterizing any multiphase crystalline nanoparticles or nanomaterials. The results highlight that combining phase identification by TKD with analytical STEM and modern data analytics may open new pathways in big data material characterization at nanoscale that may be highly beneficial for characterizing existing materials and in designing new materials.

A single-center experience with 12 consecutive cases of pregnancy among patients with membranous ventricular septal aneurysm.

BACKGROUND: Membranous ventricular septal aneurysm (MVSA) is a rare cardiac anomaly that can occur as an isolated entity or being associated with other cardiac malformations. Complications of MVSA include thromboembolism, arrhythmia, rupture, bacterial endocarditis, right ventricular outflow tract obstruction, and atrioventricular valve diseases.The success rate of pregnancy and delivery in patients with MVSA has not been reported in the literature. This study was to assess the clinical implications of this condition from our center's experience. METHODS: This was a retrospective study for consecutive 12 pregnancies in women with MVSA, who delivered at a tertiary care center in west China between May 2008 and March 2015. RESULTS: All patients with MVSA delivered via caesarian section. One patient with severe pulmonary arterial hypertension expired from pulmonary infection and heart failure after delivery. One patient terminated pregnancy in the second trimester- necessitated by cardiogenic shock. The other mothers had varying degrees of cardiac morbidity, but survived. Ten of thirteen newborns survived. Congenital heart disease and small-for-gestational-age (SGA) of newborn occurred in two cases (one twin and one single gestation). Two of these babies expired. CONCLUSIONS: Maternal and neonatal risk appeared associated with heart functional classifications, pulmonary hypertension and histories of cardiac events such as serious cardiac arrhythmia. Accurate diagnosis and care by a multidisciplinary team is recommended for pregnant woman with MVSA.