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To advance our comprehension of the complex geological history and mantle dynamics in the North Atlantic region, we employ all available broadband seismic data recorded in Greenland to reveal an abnormal mantle transition zone (MTZ) structure. Central and eastern Greenland exhibits depressed 410 and 660 km discontinuities (d410 and d660, respectively) bordering the MTZ, indicative of a substantial thermal anomaly associated with an underlying plume, surpassing the 1,800°C threshold for post‐garnet phase transitions at the d660. Variations in MTZ thickness across Greenland stem from differing temperature anomalies at the d410 and d660, possibly linked to a tilted plume within the MTZ. These findings corroborate geodynamic models, elucidating the interaction between post‐garnet phase transitions and upwelling plumes. The results shed light on the origin of the enigmatic Icelandic hotspot track and its influence on the thermal and lithospheric structures beneath Greenland. Plain Language Summary: The physical and chemical processes responsible for producing the magnificent volcanic eruptions in Iceland and the North Atlantic region are debated issues in the geoscientific community despite numerous field and laboratory studies over the past several decades. One of the hypotheses for the formation of the volcanoes is that they originate from a column of hot rocks rising from the deep mantle, that is, a mantle plume. The geometry, depth extent, and temperature anomaly of the plume are not well defined but can be constrained using the topography of two phase‐transition boundaries approximately at the globally averaged depths of 410 and 660 km, respectively. By analyzing P‐to‐S converted phases from the two discontinuities recorded by seismic stations, our results support the existence of a mantle plume that is broader than most other plumes on Earth beneath east Greenland. In addition, the results suggest that the nature of the phase transition across the 660 km discontinuity is different between the hottest core of the plume stem and the colder peripheral areas. The existence of the particular type of phase transition in the plume center can explain the large dimension of the plume, the excessive volcanism and other observations in the area. Key Points: The central and east Greenland shows abnormal mantle transition zone (MTZ) thickness, indicating a deep‐seated mantle plumeSeismic data unveil the impact of post‐garnet phase transition at the 660‐km discontinuity on mantle dynamicsVariations in MTZ thickness suggest the existence of a tilted plume and offer insights into the plume behavior [ABSTRACT FROM AUTHOR]

Aim: To understand the insulin injection knowledge, attitude and behaviour of nurses and their influencing factors in Guangdong Province. Design: Cross‐sectional study. Methods: A total of 19,853 nurses from 82 hospitals in 15 cities in Guangdong, China, participated in this study. The scores of the nurses' insulin injection knowledge, attitude and behaviour were determined through a questionnaire, and multivariate regression analysis was used to evaluate the influencing factors of insulin injection in different dimensions. STROBE. Results: Among all nurses involved in this study, 22.3% of nurses had good knowledge, 75.9% of nurses had good attitude and 92.7% of nurses had good behaviour. Pearson's correlation analysis showed that knowledge, attitude scores and behaviour scores were significantly correlated. The influencing factors of knowledge, attitude and behaviour included gender, age, education, nurse level, work experience, type of ward, diabetes nursing certification, position held and most recent insulin administration. [ABSTRACT FROM AUTHOR]

Terpene‐conjugated curcuminoids are conjugates of curcuminoids and bisabolanes in the rhizomes of Curcuma longa L. The fragmentation pathways of known three terpene‐conjugated curcuminoids (bisabolocurcumin‐ether, bisabocurcumin, and demethoxybisabolocurcumin ether) and curcumin, demethoxycurcumin, and bisdemethoxycurcumin were investigated using high‐performance liquid chromatography‐electrospray ionization tandem mass spectrometry in negative mode to rapidly search and discover similar unknown compounds of the acetone fraction of turmeric. Subsequently, compounds 1–3 were founded in the acetone fraction based on molecular weight and above fragmentation pathways (the characteristic fragment ions, the most and second most abundant fragment ions produced in MS2 spectra). Terpecurcumin X (1) and terpecurcumin Y (3) were further separated by liquid chromatography–tandem mass spectrometry guided isolation technique to verify their structures by nuclear magnetic resonance, electrospray ionization high‐resolution mass spectroscopy, ultraviolet and visible spectra and infrared spectra. Interestingly, 1 and 3 were new compounds. The results indicate the feasibility and significant advantages of liquid chromatography–tandem mass spectrometry for the rapid discovery and analysis of new constituents in traditional Chinese medicine. In vitro, Terpene‐conjugated curcuminoids had better nitric oxide inhibitory activity than the other seven curcuminoids (demethoxycurcumin, bisdemethoxycurcumin, curdione, curcumenone, bisacurone, curcumenol, and germacron). [ABSTRACT FROM AUTHOR]