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Acute kidney injury (AKI) is a common complication after surgery and is associated with detrimental outcomes. This systematic review and meta-analysis evaluated perioperative dexmedetomidine on AKI and renal function after non-cardiac surgery. PubMed, Embase, and Cochrane Library databases were searched until August 2023 for randomised trials comparing dexmedetomidine with normal saline on AKI and renal function in adults undergoing non-cardiac surgery. The primary outcome was the incidence of AKI (according to Kidney Disease Improving Global Outcomes or Acute Kidney Injury Network criteria). Meta-analysis was performed using a random-effect model. We conducted sensitivity analysis, trial sequential analysis (TSA), and Grading of Recommendations Assessment, Development and Evaluation level of evidence. Twenty-three trials involving 2440 patients were included. Dexmedetomidine administration, as compared to normal saline, significantly reduced the incidence of AKI (7.4% vs. 13.2%; risk ratio = 0.57, 95% CI = 0.40–0.83, P = 0.003, I2 = 0%; a high level of evidence); TSA and sensitivity analyses suggested the robustness of this outcome. For the renal function and inflammation parameters, dexmedetomidine decreased serum creatinine, blood urea nitrogen, cystatin C, tumour necrosis factor-α, and interleukin-6, and increased urine output and estimated glomerular filtration rate. Additionally, dexmedetomidine reduced postoperative nausea and vomiting and length of hospital stay. Dexmedetomidine was associated with an increased rate of bradycardia, but not hypotension. Dexmedetomidine administration reduced the incidence of AKI and improved renal function after non-cardiac surgery. Based on a high level of evidence, dexmedetomidine is recommended as a component of perioperative renoprotection. International Prospective Register of Systematic Reviews; Registration number: CRD42022299252. [ABSTRACT FROM AUTHOR]

With the aim of constraining the influence of the surrounding plates on the Late Paleozoic–Mesozoic paleogeographic and tectonic evolution of the southern North China Craton (NCC), we undertook new U–Pb and Hf isotope data for detrital zircons obtained from ten samples of upper Paleozoic to Mesozoic sediments in the Luoyang Basin and Dengfeng area. Samples of upper Paleozoic to Mesozoic strata were obtained from the Taiyuan, Xiashihezi, Shangshihezi, Shiqianfeng, Ermaying, Shangyoufangzhuang, Upper Jurassic unnamed, and Lower Cretaceous unnamed formations (from oldest to youngest). On the basis of the youngest zircon ages, combined with the age-diagnostic fossils, and volcanic interlayer, we propose that the Taiyuan Formation (youngest zircon age of 439 Ma) formed during the Late Carboniferous and Early Permian, the Xiashihezi Formation (276 Ma) during the Early Permian, the Shangshihezi (376 Ma) and Shiqianfeng (279 Ma) formations during the Middle–Late Permian, the Ermaying Group (232 Ma) and Shangyoufangzhuang Formation (230 and 210 Ma) during the Late Triassic, the Jurassic unnamed formation (154 Ma) during the Late Jurassic, and the Cretaceous unnamed formation (158 Ma) during the Early Cretaceous. These results, together with previously published data, indicate that: (1) Upper Carboniferous–Lower Permian sandstones were sourced from the Northern Qinling Orogen (NQO); (2) Lower Permian sandstones were formed mainly from material derived from the Yinshan–Yanshan Orogenic Belt (YYOB) on the northern margin of the NCC with only minor material from the NQO; (3) Middle–Upper Permian sandstones were derived primarily from the NQO, with only a small contribution from the YYOB; (4) Upper Triassic sandstones were sourced mainly from the YYOB and contain only minor amounts of material from the NQO; (5) Upper Jurassic sandstones were derived from material sourced from the NQO; and (6) Lower Cretaceous conglomerate was formed mainly from recycled earlier detritus. The provenance shift in the Upper Carboniferous–Mesozoic sediments within the study area indicates that the YYOB was strongly uplifted twice, first in relation to subduction of the Paleo-Asian Ocean Plate beneath the northern margin of the NCC during the Early Permian, and subsequently in relation to collision between the southern Mongolian Plate and the northern margin of the NCC during the Late Triassic. The three episodes of tectonic uplift of the NQO were probably related to collision between the North and South Qinling terranes, northward subduction of the Mianlue Ocean Plate, and collision between the Yangtze Craton and the southern margin of the NCC during the Late Carboniferous–Early Permian, Middle–Late Permian, and Late Jurassic, respectively. The southern margin of the central NCC was rapidly uplifted and eroded during the Early Cretaceous. [ABSTRACT FROM AUTHOR]

This paper reports new whole-rock geochemical, Sr–Nd–Pb isotopic, and zircon U–Pb and Hf isotopic data for Early Cretaceous intrusive rocks in the Sanmenxia–Houma area of central China, and uses these data to constrain the petrogenesis of low-Mg adakitic rocks (LMAR) and the spatial extent of the influence of the deeply subducted Yangtze slab during the Triassic evolution of this region. New zircon laser-ablation inductivity coupled plasma mass spectrometry (LA-ICP-MS) U–Pb data indicate that the early- and late-stage southern Quli, Qiligou, and Gaomiao porphyritic quartz diorites, the Canfang granodiorite, and the northern Wangmao porphyritic quartz monzodiorite were emplaced during the Early Cretaceous (~ 130 Ma) and the late Early Cretaceous (~ 116 Ma). These rocks are characterized by high Na 2 O/K 2 O, Sr/Y, and (La/Yb) n ratios as well as high Sr concentrations, low Mg # [molar 100 × Mg/(Mg + Fe 2 + tot )] values, and low heavy rare earth element and Y concentrations, all of which indicate an LMAR affinity. The samples have relatively high initial 87 Sr/ 86 Sr ratios (0.7054–0.7095), and low ε Nd (t) (− 11.90 to − 22.20) and ε Hf (t) (− 16.7 to − 32.7) values, indicative of a lower continental crust origin. The presence of Neoproterozoic (754–542 Ma) and inherited Late Triassic (220 Ma) metamorphic zircons within the late Early Cretaceous LMAR and the relatively high 206 Pb/ 204 Pb ratios of these rocks suggest that they formed from primary magmas derived from partial melting of Yangtze Craton (YC) basement material that had undergone ultrahigh-pressure metamorphism. In contrast, the presence of Paleoproterozoic and Archean inherited zircons within early Early Cretaceous LMAR in this area and the relatively low 206 Pb/ 204 Pb ratios of these rocks are indicative of derivation from primary magmas generated by partial melting of the thickened lower continental crust of the North China Craton (NCC). These rocks may have formed in an extensional environment associated with the upwelling of asthenospheric mantle material. The presence of YC basement material within the NCC in the Sanmenxia–Houma area suggests that the deeply subducted Yangtze slab influenced an area of ~ 100 km in lateral extent within the southern margin of the central NCC during the Triassic. [ABSTRACT FROM AUTHOR]

Apatite is widely utilized to reflect the character and petrogenesis of the parental felsic magma. The compositional variation of apatite from mafic rocks and its applicability to the record of whole-rock are still not well understood. In this study, we present the in situ geochemical analysis of apatite from two types of mafic rocks in the northeastern North China Craton (amphibole-rich mafic rocks for group 1, and pyroxene-rich mafic rocks for group 2). All apatite samples display typically right-sloping rare earth element (REE) patterns, with enrichment in light REE relative to heavy REE, and homogeneous Nd isotopic compositions, suggesting a magmatic origin. Higher apatite REE contents in mafic rocks of group 2 than those of group 1 show a different crystallization sequence in apatite. Extensive apatite crystallization in amphibole-rich mafic rocks, occurs earlier than in pyroxene-rich mafic rocks. The magma differentiation is responsible for the low apatite REE concentrations in group 1 mafic rocks. Combined with previous apatite data, both apatite REE patterns and compositional variations in mafic rocks are mainly controlled by the composition of the original melt. The crystallization of titanite before apatite impoverishes melts in the apatite-compatible trace elements (e.g., middle REE), whereas the crystallization of plagioclase concurrently with apatite can cause some subtle compositional variations of Sr and light REE. Apatite in mafic rocks exhibits higher Sr concentrations than in felsic rocks, which is most likely attributed to the weakening extent of the plagioclase crystallization. [Display omitted] • Apatite compositions in mafic rocks mainly depend on the parental melt. • Apatite grains from appinite crystallize earlier than those from gabbro. • The crystallization of mineral phases can cause apatite compositional variations. [ABSTRACT FROM AUTHOR]

The topsoil cyanobacteria in biological soil crusts (BSCs) play a vital role in stabilizing soil surface of disturbed habitats in water and nutrient-poor ecosystems. Currently, artificial inoculation of BSCs is considered as an effective approach to restore habitats and accelerate ecosystem regeneration. Understanding the character of cyanobacterial communities is the necessary prerequisite to explore the artificial inoculation of BSCs. For this reason, cyanobacterial communities in BSCs were compared between two mid-latitute temperate deserts with distinct precipitation patterns. The results showed that Oscillatoriales and Nostocales dominated crusts in the Tengger desert with majority of rainfall in summer and early autumn while Oscillatoriales dominated crusts in the Kyzyl kum desert with more rainfall in winter and early spring. Moreover, filamentous Microcoleus vaginatus overwhelmingly dominated all the crusts in both deserts with Mastigocladopsis sp. and Chroococcidiopsis spp. as the dominant heterocystous cyanobacteria. Of note, genus Wilmottia kept a relative stable and high abundance in both deserts. The top two abundantly shared cyanobacteria (> 1% of total sequences) were M. vaginatus and Mastigocladopsis sp. in both deserts, while 16 genera with significant variances were found between the two deserts (P <0.05). Total variations of cyanobacterial communities across the deserts were largely explained by a combination of biotic factors (microbial biomass C and N) and abiotic factors (soil pH, soil water content, soil water holding capacity, and soil available potassium). Compared to better-developed crusts, cyanobacterial abundance was higher in cyanobacterial crusts. BSC type and/or geographic location significantly affected cyanobacterial Shannon diversity without significantly influencing species richness. Our data suggest that the basic and major groups (e.g. M. vaginatus , Wilmottia spp., Mastigocladopsis sp., and Chroococcidiopsis spp.), and the abundantly shared phylotypes which showed significant difference in cyanobacterial communities between deserts, should be focused on to further explore the artificial inoculation of BSCs in temperate drylands. Unlabelled Image • Cyanobacteria in BSCs were compared between deserts with distinct rainfall patterns. • M. vaginatus predominated all the crusts in both temperate deserts. • Cyanobacterial absolute abundance was lower in better-developed BSCs. • BSC type and/or geographic location significantly affected Shannon diversity. • M. vaginatus , Wilmottia , Mastigocladopsis and Chroococcidiopsis are potential efficient inoculums. [ABSTRACT FROM AUTHOR]