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It is well established that Cretaceous magmatism in the South China Block (SCB) is related to the Paleo‐Pacific subduction. However, the starting time and the associated deep crust‐mantle processes are still debatable. Mafic dike swarms carry important information on the deep earth (including mantle) geodynamics and geochemical evolution. In the Jiangnan Orogen (South China), there is no information on whether the Mesozoic magmatic activities in this region are also directly related to the Pacific subduction or not. In this study, we present detailed zircon U‐Pb geochronological, whole‐rock element and Sr‐Nd isotope data for Early Cretaceous Tuanshanbei dolerite dikes, and provide new constraints on the condition of the lithospheric mantle and mantle dynamics of the SCB during that time. LA‐ICP‐MS zircon U‐Pb dating suggests that this dolerite erupted in the Early Cretaceous (∼145 Ma). All samples have alkaline geochemical affinities with K2O + Na2O = 3.11–4.04 wt%, K2O/Na2O = 0.50–0.72, and Mg# = 62.24–65.13. They are enriched in LILE but depleted in HFSE with higher initial 87Sr/86Sr ratio (0.706896–0.714743) and lower εNd(t) (–2.61 to –1.67). They have high Nb/U, Nb/La, La/Sm and Rb/Sr, and low La/Nb, La/Ta, Ce/Pb, Ba/Rb, Tb/Yb and Gd/Yb ratios. Such geochemical signatures suggest that the fractional crystallization is obvious but crustal contamination play a negligible role during magmatic evolution. Tuanshanbei dolerite were most likely derived from low‐degree (2%–5%) partial melting of a phlogopite‐bearing mantle material consisted of ∼85% spinel peridotite and ∼15% garnet peridotite previously metasomatized by asthenosphere‐derived fluids/melts with minor subduction‐derived fluids/melts. Slab‐rollback generally lead to the upwelling of the hot asthenosphere. The upwelling of asthenosphere consuming the lithospheric mantle by thermo‐mechanical‐chemical erosion. The lithospheric mantle may have partially melted due to the heating by the upwelling asthenosphere and lithospheric extension. It is inferred that the Tuanshanbei dolerite might be associated with the initial slab rollback and corresponding lithospheric extension occurred potentially at ca. 145 Ma. [ABSTRACT FROM AUTHOR]

Simple Summary: Pseudobagrus ussuriensis is a high-value fish species widely distributed in various river basins across China. Its benthic lifestyle and lack of scales make its skin susceptible to damage, leading to diseases and mortality. Hypoxia represents a significant factor affecting fish health, whether in captive environments or natural water bodies. Exposure to low oxygen levels can result in various adverse effects, including causing an immune response in fish. In this study, we aimed to elucidate the differential immune responses of distinct tissues to acute hypoxia and reoxygenation by analyzing the histophysiological and transcriptional changes in the brain and skin of P. ussuriensis. Our findings revealed that both the brain and skin exhibited immune responses to hypoxia, which persisted even after reoxygenation. However, it was observed that the overall immune response intensity in the brain was lower than that in the skin. This research provides novel insights into the molecular mechanisms underlying the response of P. ussuriensis to hypoxia stress. Pseudobagrus ussuriensis is an unscaled fish that is more susceptible to skin damage than scaled fish. To investigate the impacts of hypoxia and reoxygenation on skin and brain immunity, juvenile P. ussuriensis were subjected to hypoxia conditions (DO: 0.8 ± 0.05 mg/L) for durations of 0, 3, 6, and 12 h, followed by 12 h of reoxygenation (DO > 6 mg/L). Histological analysis showed a significant increase in the number of skin mucosal cells after 12 h of hypoxia and a significant decrease after 12 h of reoxygenation when compared to the control group. As the duration of hypoxia increased, an increase in antioxidant (SOD, CAT, GSH, MDA) and immune (cortisol, LZM) physiological parameters of the skin and brain appeared. The results of transcriptomic studies showed that the number of differential genes was greater in skin than in brain. Most of the immune pathways in both tissues under hypoxia conditions were all nonspecific immunity (TNF, IL-17, chemokines), while both tissues maintained their homeostasis through active energy supply and cell cycle regulation. Meanwhile, both physiological parameters and RNA transcriptome results showed that 12 h of reoxygenation could not completely eliminate the negative effects of 12 h of hypoxia. This study offers new insights into the immune responses of P. ussuriensis skin and brain during acute hypoxia and reoxygenation. [ABSTRACT FROM AUTHOR]

The newly identified Neoproterozoic Yuanmou high-Nb mafic and adakitic rocks at the western margin of the Yangtze Block in South China are investigated for petrogenesis and geodynamic implications. Zircon U-Pb ages show the adakitic granodiorite host and mafic microgranular enclaves (MMEs) were synchronously emplaced at 811-806 Ma, and were cut by an 802 ± 11.5 Ma mafic dike. The medium-grained granodiorites consist mainly of plagioclase, quartz, K-felspar, biotite, and amphibole. High SiO2 (62.8-67.5 wt%), Al2O3 (13.1-16.8 wt%) contents, high Sr/Y (17.4-49.0), and (La/Yb)N (16.3-52.6) but low Y (6.83-16.1 ppm) and Yb (0.74-1.82 ppm) concentrations of the granodiorites point toward their calc-alkaline and adakitic nature. Further, their high Dy/Yb (1.52-2.31) and Gd/Y (2.35-4.43) and low K2O/Na2O (0.22-0.48) and Th/La (0.14-0.20) ratios, constant bulk rock εNd(t) (-0.5 to -1.5) and zircon εHf(t) (0.0 to +2.3) values, suggest that the granodiorites were derived from partial melting of a mafic lower crustal source. The MMEs in the granodiorites and mafic dike intrusions are composed of amphibole, plagioclase, clinopyroxene, and olivine, and have similar chemical compositions, such as high Nb (15.7-41.9 ppm) and TiO2 (2.13-3.39 wt%) contents and high Nb/U (18.7-30.9) values, akin to alkaline high-Nb basalts (HNB). Their variable Ba/Nb (7.68-79.2), Nb/Zr (0.09-0.16), high Nb/Th (5.47-6.68), and low Th/Zr (0.01-0.03) and La/Nb (1.03-1.37) ratios indicate a mantle source modified by melts derived from subducted oceanic crust and sediments. The Yuanmou HNB with high εNd(t) (+4.8 to +6.9) were probably generated during back-arc extension by decompression melting of a mantle source metasomatized by adakitic slab melts formed during earlier stages of the subduction. This implies that the location of the back-arc was far from the subducted oceanic slab, possibly due to a slab rollback process. In this scenario, HNB intrusions provided the heat for partial melting and adakitic melt formation in the mafic lower crust. The model suggests that the Yuanmou and other similar associations of HNBs and adakitic rocks emplaced along the western margin of the Yangtze Block are products of a widespread Neoproterozoic back-arc extension. [ABSTRACT FROM AUTHOR]

The ophiolites along the North Qilian Orogenic Belt are considered to be fragments of ancient oceanic crusts and lithospheric mantle of the Palaeozoic North Qilian Ocean (a branch of the Proto‐Tethys). Compared with other ophiolites in this belt, the genesis of the Xiejiayao ophiolite has been poorly studied so far, making it difficult to understand the tectonic evolution of the ocean. In this study, we present new compositional and Sr‐Nd isotopic analyses of basaltic rocks from the Xiejiayao ophiolite to shed light on its petrogenesis and geodynamic background. These oceanic basalts are characterized by flat REE patterns, low elemental ratios of high‐field‐strength elements (e.g., La/Sm, Sm/Yb, La/Yb, Gd/Yb, [Th/Yb]PM) and abundant spinels, implying that they were generated via partial melting in the spinel stability field of the mantle. Their positive εNd(t) values (6.1–8.4), high Zr/Nb (43.65–79.40) as well as low Nb/Ta (10.91–15.09), Zr/Hf (34.64–39.28), and Nb/Yb (0.41–0.59) ratios further reflect that the ancient mantle had already become depleted to some extent before the onset of the Palaeozoic ocean. Additionally, basalts share many geochemical similarities (e.g., Zr, Y, Ti, and V) with both mid‐ocean ridge and island arc basalts. This supports the strong likelihood of origin in a back‐arc basin close to the suprasubduction zone for the ophiolite. Therefore, accompanied by the northward subduction of the oceanic lithosphere during the early Palaeozoic, a large‐scale back‐arc basin developed progressively in response to the back‐arc expansion. The Xiejiayao basaltic magmas were generated in the back‐arc basin via partial melting of the depleted mantle and their source was probably mixed with subducted melts/fluids from the dehydration and melting of oceanic slabs and sediments. [ABSTRACT FROM AUTHOR]

Karst is a unique landform formed by strong chemical weathering of carbonate rocks. This study investigated the concentration and speciation of rare earth elements and yttrium (REY) in alluvial soils and REY fractionation from carbonate rocks and alluvial soils in the world's largest contiguous karst landform in southwestern China. The results showed that the REY of alluvial soils ranged from 73.77 to 1251.56 μg⋅g−1, with a median value of 230.30 μg⋅g−1, which was higher than that of alluvial soils across China (178 μg⋅g−1) and the upper continental crust (168 μg⋅g−1), revealing a high background of REY in these karst areas. Meanwhile, the average REY in alluvial soils (244.96 μg⋅g−1) was close to 14 times that in carbonate rocks (17.61 μg⋅g−1) in the study area, indicating that REY was significantly enriched in the pedogenesis. Correlation analysis showed that the REY concentration was not significantly related to any single factor (i.e., Fe 2 O 3 , MnO, Al 2 O 3 , TOC, pH, or CIX). BCR speciation analysis revealed a declining trend in the proportion of REY across the residual (F4, 73.21 %), reducible (F2, 19.40 %), oxidizable (F3, 6.89 %), and weakly acid-extracted (F1, 0.50 %) phases. Additionally, significant REY fractionations from carbonate rocks to alluvial soils were observed. The bedrock-normalized REY pattern revealed an enrichment of light rare-earth elements (LREE) and middle rare-earth elements (MREE), a depletion of heavy rare-earth elements and yttrium (HREY), and positive Ce and Gd anomalies. Secondary mineral phases that formed during weathering—such as clay minerals, oxyhydroxides, phosphates, and organic matter—played an important role in the retention and fractionation of the REY in the soils. Besides these natural factors, anthropogenic inputs also contributed to the REY fractionation, as indicated by the slight positive Gd anomaly in the karst alluvial soils. Furthermore, the differences of δCe and δEu in the soils developed from three types of pedogenic rocks—including carbonate, basalt, and granite—were discussed. The different δEu anomalies could help to identify the parent rocks of alluvial soils. • REY was enriched in alluvial soils during pedogenesis in karst landform, southwestern China. • Distinct REY fractionations were observed in different phases of alluvial soil. • The positive δGd indicated the anthropogenic Gd contaminated the alluvial soil. • The distinguished δCe and δEu could be used in the source apportionment of alluvial soil. [ABSTRACT FROM AUTHOR]

• The supply-demand balance of gadolinium (Gd) in China is quantified and compared. • China's consumption of Gd has exceeded its' supply since 2011. • The increasing demand of NdFeB magnets will lead to Gd shortage in 2030. • Material flows analysis on holistic perspectives is needed for supply chain management. Our understanding of supply and demand conflicts of critical minerals is quite limited, which may inhibit strategies in their criticality mitigation. This is particularly severe for gadolinium (Gd), as a heavy rare earth element, given its small amounts in supply and wide applications ranging from glass to NdFeB magnets. This study (1) developed a sophisticated accounting framework to measure the supply and demand trends of Gd within China from 1990 to 2018 and (2) provided a qualitative review and discussions on Gd supply-demand balance in a holistic perspective. Our findings suggest that the balance of Gd supply and demand shows a cyclical trend, termed as periodic "scarcity-abundance" pattern, influenced by changes in environmental regulations, trade structures, and technological applications. This highlights the importance of the joint measurement of both supply and demand of critical minerals for their criticality mitigation. [Display omitted] [ABSTRACT FROM AUTHOR]

Conclusions: Noninvasive standard evaluation of normal endolymphatic space and endolymphatic hydrops using magnetic resonance imaging (MRI) in various age groups is reported for the first time. Objective: To compare the standard evaluation of endolymphatic space in healthy volunteers in the cochlea and the vestibule among different age groups by applying noninvasive intratympanic gadolinium (Gd) perfusion through the eustachian tube and three-dimensional fluid-attenuated inversion recovery MRI (3D-FLAIR MRI). Methods: This was a prospective study. 3D-FLAIR MRI was performed with a 3 T unit 24 h after intratympanic administration of Gd through the eustachian tube in 60 healthy volunteers aged 20-55 years. Pure-tone test and tympanometry were performed 24 h before and 1 week after Gd administration. Results: There was no significant difference in the ratios of the area of the endolymphatic space to that of the fluid space in the cochlea and the vestibule between males and females, or among 20-30-, 31-44-, and 45-55-year-old healthy volunteers. In 20-55-year-old healthy volunteers, the normal value of the endolymphatic space in the cochlea ranged between 7% and 27%, and that in the vestibule was between 17% and 39%. No significant changes in pure-tone test or tympanometry were noted. [ABSTRACT FROM AUTHOR]

Background: Unlike most other commodities, rare earth elements (REEs) are part of a wide range of applications needed for daily life all over the world. These applications range from cell phones to electric vehicles to wind turbines. They are often declared as part of "green technology" and, therefore, often called "green elements". However, their production and use are not only useful but also risky to the environment and human health, as many studies have shown. Consequently, the range of global research efforts is broad and highly variable, and therefore difficult to capture and assess. Hence, this study aims to assess the global parameters of global research on REE in the context of environment and health (REE eh ). In addition to established bibliometric parameters, advanced analyses using market driver and scientific infrastructure values were carried out to provide deep insight into incentives, necessities, and barriers to international research., Results: The focus of REE research is in line with national aspirations, especially from the major global players, China and the USA. Whereas globally, regional research interests are related to market interests, as evidenced by the inclusion of drivers such as electric vehicles, wind turbines, and permanent magnets. The topics receiving the most attention are related to gadolinium used for magnetic resonance imaging and the use of ceria nanoparticles. Since both are used for medical purposes, the medical research areas are equally profiled and mainly addressed in high-income countries. Nevertheless, environmental issues are increasingly in focus., Conclusions: There is still a need for research that is independent and open-ended. For this, market-independent technologies, substitutes and recycling of REEs need to be addressed scientifically. The results of this study are relevant for all stakeholders, from individual scientists to planners to funders, to improve future research strategies in line with these research mandates., (© 2022. The Author(s).)

The increasing complexity of reservoirs, particularly shale reservoirs, demands accurate information on the formation composition, mineralogy, and mechanical parameters for effective exploitation. The development of geochemical and geophysical logging technology allows the investigation of the correlations between the elemental, mineral contents, and the mechanical parameters of shale. Taking the Lower Cambrian Niutitang Formation shale in the Fenggang block in northeastern Guizhou as an example, 889 data sets of the main elemental (Si, Ca, Fe, S, Ti, Gd, K, Mg, and S) concentrations and minerals (carbonate, pyrite, clay, quartz, feldspar, and mica) from Elemental Capture Spectroscopy logging and rock mechanics parameters (dynamic Young's modulus, dynamic Poisson's ratio, shear modulus, bulk modulus, and brittleness index) determined via Sonic Scanner logging data in the target zone of the study area are collected. We investigated the relationships between the mechanical parameters and the elemental, and mineral concentrations by Spearman rank correlation analysis. The influence of different Si concentrations on the mechanical parameters of the rock (positive/negative, and significance) is discussed based on the mineral contents determined via X-ray diffraction of 24 experimental samples. When 22.1% < DWSi (dry weight fraction of the silicon content as a percent) < 28.40% and 28.40% < DWSi <34.20%, the static Young's modulus, shear modulus, bulk modulus, and brittleness index exhibit a highly positive/negative correlation that is significant with the increase/decrease in DWSi, WCLA (dry weight fraction of clay), and WQFM (dry weight fraction of quartz, feldspar, and mica) contents, respectively. DWSi = 28.4% is suggested as the turning point for the correlation change (positive/negative, significance). Thus, there exists uncertainty in the determination of the mechanical parameters of rock within certain elemental content ranges. More mathematical models and factors need to be considered to adequately characterize the mechanical parameters of rock. • Rock's elemental and mineral and mechanical parameters characterization in the Lower Cambrian Niutitang Formation shale. • Spearman rank analysis on elements, minerals and mechanical parameters of a rock. • Discuss the degree of Spearman rank correlations regarding elements and minerals on mechanical parameters. • Discuss the possible mineral sources of silicon in different ranges. [ABSTRACT FROM AUTHOR]

Abstract: The Daya Bay experiment aims to measure the last unknown neutrino mixing angle, sin2(2θ13), to a sensitivity of .01. The detection method requires “identical” near and far detectors each with a precisely known target mass on the order of 20,000kg. A calibrated filling system able to fill the required 20,000kg of Gd-doped scintillating liquid (GDLS) to an accuracy of <±6kg or 0.03% is described. [Copyright &y& Elsevier]

Conclusions: A new method for noninvasive standard evaluation of normal endolymphatic space and endolymphatic hydrops using magnetic resonance imaging (MRI) is indicated. Objective: To standardize the evaluation of endolymphatic space in the cochlea and the vestibule in healthy volunteers by applying noninvasive intratympanic gadolinium (Gd) perfusion through the eustachian tube and three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI). Methods: This was a prospective study. 3D-FLAIR MRI was performed with a 3 Tesla (3 T) unit 24 h after intratympanic administration of Gd through the eustachian tube in 20 healthy volunteers. Pure tone test and tympanometry were performed 24 h before Gd was administered, and 24 h and 1 month after Gd administration. Results: Gd was present in the perilymph of the inner ear, which clearly displayed the endolymphatic space on 3D-FLAIR MRI with a visible borderline between the perilymph and the endolymph. In healthy volunteers, the normal value for the endolymphatic space in the cochlea ranged between 9% and 28%, and that in the vestibule was between 14% and 40%. No significant changes in pure tone test and tympanometry were noted. [ABSTRACT FROM AUTHOR]

• Archean Huangling greenstone belt is preserved as amphibolites in Yangtze Craton. • The protoliths of amphibolites include komatiite, komatiitic and tholeiitic basalt. • The tholeiitic basalts originated from a mantle plume head. • The komatiites originated from a mantle plume tail. • These ultramafic–mafic lavas erupted in a continental rift. The Archean Huangling greenstone belt (HGB) is preserved as amphibolites in the Huangling granite–greenstone terrane, Yangtze Craton. Geologically and geochemically, the amphibolites are metavolcanic rocks and can be subdivided into amphibole schist, massive amphibolite and banded amphibolite, with komatiite, komatiitic basalt and tholeiitic basalt protoliths, respectively. The komatiites have high MgO (20–30%), Cr, Co and Ni contents; low Rb, Sr, Ba and ΣREE contents; and slight LREE depletion and HREE enrichment, characterizing them as the Al-undepleted type according to the criteria (CaO/Al 2 O 3) adj ˃ 20, (Al 2 O 3 /TiO 2) adj and (Gd/Yb) PM < 1. The komatiitic basalts and tholeiitic basalts have lower MgO (5–16%), Cr, Co and Ni contents; higher Rb, Sr, Ba and ΣREE contents; and slight LREE enrichment and HREE depletion. The geochemical plots (Zr/Y vs. Nb/Y, Nb/Yb vs. Th/Yb, La/Ta vs. La/Sm and Y vs. Zr/Y), negative Nb anomalies, wide Ɛ Nd values (−8.0 to +6.2), negative zircon Ɛ Hf values (−11.59 to −3.98), and old T Nd (DM) (3.9–2.9 Ga) and zircon T Hf (DM) ages (3.9–3.3 Ga) of the amphibolites reflect a mantle source with slight crustal contamination and show that the komatiitic basalts and tholeiitic basalts are more closely related to each other than to the komatiites. The tholeiitic basalts originated from moderate-degree melting of a mantle plume head, the komatiitic basalts originated from the fractional crystallization of tholeiitic basalt melts as cumulates, and the komatiites originated from high-degree melting of the mantle plume tail with garnet entering the melt phase. These high-Mg lavas erupted in a continental rift when the mantle plume impinged on the continental lithosphere, generating rifting and subsequent volcanic eruptions. These ultramafic–mafic rocks (3.2–3.0 Ga) formed the HGB, which was subsequently intruded by TTG (3.0–2.9 Ga), together forming the Archean Huangling granite–greenstone terrane in the Yangtze region. [ABSTRACT FROM AUTHOR]

Background: Preclinical studies and pilot patient studies have shown that chronic infarctions can be detected and characterized from cardiac magnetic resonance without gadolinium-based contrast agents using native-T1 maps at 3T. We aimed to investigate the diagnostic capacity of this approach for characterizing chronic myocardial infarctions (MIs) in a multi-center setting., Methods: Patients with a prior MI (n=105) were recruited at 3 different medical centers and were imaged with native-T1 mapping and late gadolinium enhancement (LGE) at 3T. Infarct location, size, and transmurality were determined from native-T1 maps and LGE. Sensitivity, specificity, receiver-operating characteristic metrics, and inter- and intraobserver variabilities were assessed relative to LGE., Results: Across all subjects, T1 of MI territory was 1621±110 ms, and remote territory was 1225±75 ms. Sensitivity, specificity, and area under curve for detecting MI location based on native-T1 mapping relative to LGE were 88%, 92%, and 0.93, respectively. Native-T1 maps were not different for measuring infarct size (native-T1 maps: 12.1±7.5%; LGE: 11.8±7.2%, P =0.82) and were in agreement with LGE ( R 2 =0.92, bias, 0.09±2.6%). Corresponding inter- and intraobserver assessments were also highly correlated (interobserver: R 2 =0.90, bias, 0.18±2.4%; and intraobserver: R 2 =0.91, bias, 0.28±2.1%). Native T1 maps were not different for measuring MI transmurality (native-T1 maps: 49.1±15.8%; LGE: 47.2±19.0%, P =0.56) and showed agreement ( R 2 =0.71; bias, 1.32±10.2%). Corresponding inter- and intraobserver assessments were also in agreement (interobserver: R 2 =0.81, bias, 0.1±9.4%; and intraobserver: R 2 =0.91, bias, 0.28±2.1%, respectively). While the overall accuracy for detecting MI with native-T1 maps at 3T was high, logistic regression analysis showed that MI location was a prominent confounder., Conclusions: Native-T1 mapping can be used to image chronic MI with high degree of accuracy, and as such, it is a viable alternative for scar imaging in patients with chronic MI who are contraindicated for LGE. Technical advancements may be needed to overcome the imaging confounders that currently limit native-T1 mapping from reaching equivalent detection levels as LGE.

Rare earth elements (REEs), known as "industrial vitamins", are widely used in medical treatment, industry, agriculture, etc. However, with the increasing demand for REEs, excess REEs, such as gadolinium (Gd), are considered micropollutants in the environment. In this paper, the distributions of dissolved REEs were analyzed in three small streams, in order to determine the extent and occurrence of Gd anomalies. The shale-normalized REE patterns in the three streams were less smooth with heavy REEs higher than light REEs, for a weak reaction of the heavy REE complexes. A negative Ce (cerium) anomaly and positive samarium (Sm) and europium (Eu) anomalies were observed in the three streams and the negative Ce anomaly was affected by the pH of the alkaline rivers. However, a positive Gd anomaly was found in only a typical urban small stream, Jinzhong. With a population of approximately 60,000, Jinzhong runs by a hospital and through wastewater treatment plants (WWTPs). The concentrations of Gd in Jinzhong ranged from 1.54 to 86.65 ng/L with high anthropogenic Gd proportions (63.64%-98.07%). Anthropogenic Gd showed significant seasonal variations and distinct spatial disparities from upstream to downstream, and it was associated with certain ions such as Cl - . Anthropogenic Gd could be attributed to gadopentetic acid (Gd-DTPA), which is used in magnetic resonance imaging (MRI) in hospitals. This type of Gd was shown to be correlated with municipal wastewater. Due to the high stability and low particulate reactivity in water, anthropogenic Gd has great potential to serve as a tracer to prove the presence of medical wastewater.

Importance: Myocardial scarring leads to cardiac dysfunction and poor prognosis. The prevalence of and factors associated with unrecognized myocardial infarction and scar have not been previously defined using contemporary methods in a multiethnic US population., Objective: To determine prevalence of and factors associated with myocardial scar in middle- and older-aged individuals in the United States., Design, Setting, and Participants: The Multi-Ethnic Study of Atherosclerosis (MESA) study is a population-based cohort in the United States. Participants were aged 45 through 84 years and free of clinical cardiovascular disease (CVD) at baseline in 2000-2002. In the 10th year examination (2010-2012), 1840 participants underwent cardiac magnetic resonance (CMR) imaging with gadolinium to detect myocardial scar. Cardiovascular disease risk factors and coronary artery calcium (CAC) scores were measured at baseline and year 10. Logistic regression models were used to estimate adjusted odds ratios (ORs) for myocardial scar., Exposures: Cardiovascular risk factors, CAC scores, left ventricle size and function, and carotid intima-media thickness., Main Outcomes and Measures: Myocardial scar detected by CMR imaging., Results: Of 1840 participants (mean [SD] age, 68 [9] years, 52% men), 146 (7.9%) had myocardial scars, of which 114 (78%) were undetected by electrocardiogram or by clinical adjudication. In adjusted models, age, male sex, body mass index, hypertension, and current smoking at baseline were associated with myocardial scar at year 10. The OR per 8.9-year increment was 1.61 (95% CI, 1.36-1.91; P < .001); for men vs women: OR, 5.76 (95% CI, 3.61-9.17; P < .001); per 4.8-SD body mass index: OR, 1.32 (95% CI, 1.09-1.61, P = .005); for hypertension: OR, 1.61 (95% CI, 1.12-2.30; P = .009); and for current vs never smokers: 2.00 (95% CI, 1.22-3.28; P = .006). Age-, sex-, and ethnicity-adjusted CAC scores at baseline were also associated with myocardial scar at year 10. Compared with a CAC score of 0, the OR for scores from 1 through 99 was 2.4 (95% CI, 1.5-3.9); from 100 through 399, 3.0 (95% CI, 1.7-5.1), and 400 or higher, 3.3 (95% CI, 1.7-6.1) (P ≤ .001). The CAC score significantly added to the association of myocardial scar with age, sex, race/ethnicity, and traditional CVD risk factors (C statistic, 0.81 with CAC vs 0.79 without CAC, P = .01)., Conclusions and Relevance: The prevalence of myocardial scars in a US community-based multiethnic cohort was 7.9%, of which 78% were unrecognized by electrocardiography or clinical evaluation. Further studies are needed to understand the clinical consequences of these undetected scars.