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[Display omitted] • Coronary microvascular dysfunction (CMD) & obstructive coronary artery disease (OCAD). • 22 global electrical heterogeneity (GEH) features from CMD and OCAD patients. • Non-invasively differentiating CMD & OCAD: AUC 0.717 ([95 % CI 0.636–0.798], p < 0.0001). • Two GEH parameters are effective indicators for differentiating CMD and OCAD. • On validation set: sensitivity, 0.606; specificity, 0.611; accuracy, 0.608. Both coronary microvascular dysfunction (CMD) and obstructive coronary artery disease (OCAD) cause myocardial ischemia, making accurate diagnosis of CMD an unmet challenge. We investigate whether electrocardiogram (ECG)-constructed global electrical heterogeneity (GEH) can differentiate CMD and OCAD. This retrospective study comprised 74 OCAD and 77 CMD patients with their clinical characteristics and ECGs. QRS onset and offset, R-peak, and T-wave offset were marked on vector-magnitude (VM) derived from ECG-constructed time-coherent global XYZ median beats. 22 GEH parameters (i.e., QT Interval, area and peak QRS-T angles, the area under curve of QT interval on VM (AUC_QT_VM), the direction (azimuth and elevation) and magnitudes of the spatial peak and area vectors for QRS, T, and spatial ventricular gradient (SVG) were calculated and tested using logistic regression analyses to identify significant predictors. Six GEH parameters (i.e., QT Interval, Peak QRS Azimuth, Area QRS Azimuth, Area T Elevation, Area T, and Area SVG Elevation) were identified as significant predictors. After multivariable adjustment, AUC_QT_VM (odds ratio (OR) = 0.979, [95 % confidence interval (CI) 0.964–0.995], P = 0.009), Area SVG Elevation (OR = 0.978, [95 % CI 0.959–0.998], P = 0.031), and QT Interval (OR = 1.014, [95 % CI 1.000–1.024], P = 0.010) were selected, with the area under curve (AUC) of 0.717 ([95 % CI 0.636–0.798], P < 0.0001) and accuracy of 0.645 on the training dataset and accuracy of 0.608 on the validation dataset. Area SVG Elevation and QT Interval could differentiate CMD and OCAD, indicating that our proposed GEH-based method may offer a new possibility and pathway for non-invasive detection of CMD. [ABSTRACT FROM AUTHOR]

Abstract In this study, nineteen brine samples from the Qarhan Salt Lake (QSL) in western China were collected and analyzed for boron (B) and chlorine (Cl) concentrations, total dissolved solids (TDS), pH values and stable B isotopic compositions. The B concentrations and δ 11B values of brines in the QSL range from 51.6 mg/L to 138.4 mg/L, and from +9.32‰ to +13.08‰, respectively. By comparison of B concentrations and TDS of brines in QSL with evaporation paths of brackish water, we found that B enrichment of brines primarily results from strong evaporation and concentration of Qarhan lake water. Combining with comparisons of B concentrations, TDS, pH values and δ 11B values of brines, previously elemental ratios (K/Cl, Mg/Cl, Ca/Cl, B/Cl) and δ 11B values of halite from a sediment core (ISL1A), we observe good correlations between B concentrations and TDS, TDS and pH values, pH and δ 11B values of brines, which demonstrate that higher B concentrations and more positive δ 11B values of halite indicate higher salinity of the Qarhan paleolake water as well as drier paleoclimatic conditions. Based on this interpretation of the δ 11B values of halite in core ISL1A, higher salinity of the Qarhan paleolake occurred during two intervals, around 46–34 ka and 26–9 ka, which are almost coincident with the upper and lower halite-dominated salt layers in core ISL1A, drier climate phases documented from the δ 18O record of carbonate in core ISL1A and the paleomoisture record in monsoonal central Asia, and a higher solar insolation at 30°N. These results demonstrate that the δ 11B values of halite in the arid Qaidam Basin could be regarded as a new proxy for reconstructing the salinity record of paleolake water as well as paleoclimate conditions. Graphical abstract Highlights • δ 11B values of 40 halite in ISL1A and 19 brines in Qarhan playa were analyzed. • High (low) B concentrations correspond to high (low) δ 11B values of halite in ISL1A. • The δ 11B values of halite coincide with δ 18O values of carbonates in ISL1A. • The δ 11B values of halite in ISL1A indicate the salinity of Qarhan paleolake water. • The sedimentary environment can be divided into three stages. [ABSTRACT FROM AUTHOR]

Abstract: Qarhan playa is located in the eastern-central Qaidam Basin in the northeastern Qinghai-Tibetan Plateau. As a lake-depocenter since the Pleistocene and surrounded by Gobi and yardang fields, it might have deposited abundant aeolian materials. Distinguishing its aeolian signature from lacustrine sediments is important for understanding the landform processes and environmental changes, which is the focus of the current study. Based on major-elements analysis, microtextures of quartz grains, and features of grain-size frequency curves and other grain-size parameters, we demonstrate the existence of aeolian component in the lacustrine sequences of a 102m core (ISL1A). Grain-size distribution curve statistics on 60 samples from two extreme palaeoclimate environments (hyperarid and humid), as well as multi-proxies records comparison, indicate that the mode at about 40μm represents the aeolian component and the 10–70μm fraction of grain-size is a valid proxy of East Asian winter monsoon, and that the 70–650μm fraction represents the intensity of dust storms. The erosive lacustrine sediments in the western Qaidam Basin and the alluvial/fluvial fans in nearby piedmont are probably important sources for these aeolian materials. The similarities of major-element data for samples from the Qaidam Basin (both lacustrine and loess), Qinghai Lake (loess), and the Chinese Loess Plateau (loess) indicate that the Qaidam Basin is a dust source for the loess in Qinghai Lake and the Chinese Loess Plateau. [Copyright &y& Elsevier]