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We report herein on new zircon U-Pb ages, the major and trace elements of whole-rock, and the Sr-Nd-Hf isotope composition for adakitic intrusives collected from the West Ujimqin district in the Southeast region of the Central Asian Orogenic Belt (CAOB). These data provide important constraints on the petrogenetic evolution and geodynamic setting of late Permian magmatism in the Southeast CAOB. The U-Pb dating of zircon shows that the ages of Seerbeng pluton and Nuhetingshala pluton in West Ujimqin are 255.3 [+ or -] 0.71 and 254.4 [+ or -] 1.2 Ma, respectively, which signifies that these are products of magmatic activity in the late Permian. The adakitic intrusives are characterized by high levels of Sr (Sr > 741 ppm), low Y, low Yb, high Sr:Y ratios, and strongly fractionated rare earth elements (10.3 < [La.sub.N]/[Yb.sub.N] < 22.5), which is similar to the features of the adakite. The magmatic zircons exhibit positive Hf values (+8.1 to +13.3), and young two-stage model ages vary from 430 to 760 Ma. The high eNd(t) and low ([.sup.87]Sr: Key words: adakite, late Permian, U-Pb age of zircon, slab break-off Nous rendons compte de nouvelles dates U-Pb sur zircons et donnees sur les elements majeurs et en traces sur roche totale et de la composition des isotopes de Sr-Nd-Hf pour des roches intrusives adakitiques du district d'Ujimqin occidental dans le secteur sud-est de la ceinture orogenique dAsie centrale (COAC). Ces donnees fournissent d'importantes contraintes concernant l' evolution petrogenetique et le milieu geodynamique du magmatisme permien tardif dans le sudest de la COAC. La datation U-Pb sur zircons montre que les ages des plutons de Seerbeng et de Nuhetingshala dans l'Ujimqin occidental sont de 255,3 [+ or -] 0,71 et 254,4 [+ or -] 1,2 Ma, respectivement, ce qui signifie qu'ils sont des produits d'une activite magmatique au Permien tardif. Les roches intrusives adakitiques sont caracterisees par de fortes concentrations de Sr (Sr > 741 ppm), de faibles concentrations de Y et Yb, ainsi que des rapports Sr : Y eleves et des terres rares fortement fractionnees (10,3 < [La.sub.N]/[Yb.sub.N] < 22,5), ce qui s'apparente aux caracteristiques des adakites. Les zircons magmatiques presentent des valeurs de Hf positives (+8,1 a +13,3), et les ages de modeles en deux etapes jeunes vont de 430 a 760 Ma. Les valeurs eNd(t) elevees et de ([.sup.87]Sr : Mots-cles: adakite, Permien tardif, age U-Pb sur zircons, rupture de la plaque., Introduction The Central Asian Orogenic Belt (CAOB) is the largest accretion orogenic belt and the most prominent area of continental crust growth in the world. The geotectonic division of the [...]

The petrogenesis and geodynamic implications of the Early Paleozoic adakitic rocks in the east of Inner Mongolia remain topics of debate. This study presents new petrology data through zircon U-Pb age and Lu-Hf isotopic composition, whole-rock major-trace element geochemistry, and Sr-Nd isotopes from adakitic rocks. The zircon U-Pb dating results demonstrate that the formation age is 242.8 ± 1.0 Ma, which is the product of Early Triassic magmatism. Petrology and geochemical study have shown that the granodiorite have high SiO2 (66.93~69.40%), Al2O3 (15.37~15.43%), and MgO (1.35~1.55%), with LREE enrichment and HREE deficit, and they have high Sr, low Y, and high Sr/Y ratios, showing typical signatures of adakitic rocks. The εHf(t) values of zircon vary between +11.3 and +13.8, with low whole-rock (87Sr/86Sr)i (0.703382) and positive εNd(t) values, and the average Mg# of the rock is 56.14, suggesting that adakite derived from partial melting of MORB materials and magma interaction with the mantle. Comprehensive analysis suggests that during the Late Permian to Early Triassic, the subducted slab of the Paleo-Asian Ocean broke off, and the residual oceanic slab preserved in the mantle beneath the subduction zone underwent partial melting, generating adakitic magma. [ABSTRACT FROM AUTHOR]

Post-stroke depression (PSD), one of the most common complications following stroke, affects approximately one-third of stroke patients and is significantly associated with increased disability and mortality as well as decreased quality of life, which makes it an important public health concern. Treatment of PSD significantly ameliorates depressive symptoms and improves the prognosis of stroke. The authors discuss the critical aspects of the clinical application of prediction and preventive treatment of PSD. Then, the authors update the biological factors associated with the onset of PSD. Furthermore, they summarize the recent progress in pharmacological preventive treatment in clinical trials and propose potential treatment targets. The authors also discuss the current roadblocks in the preventive treatment of PSD. Finally, the authors put postulate potential directions for future studies so as to discover accurate predictors and provide individualized preventive treatment. Sorting out high-risk PSD patients using reliable predictors will greatly assist PSD management. Indeed, some predictors not only predict the incidence of PSD but also predict prognosis, which indicates that they might also aid the development of an individualized treatment scheme. Preventive application of antidepressants may also be considered. [ABSTRACT FROM AUTHOR]

Current white light emitting diodes (WLEDs) have poor thermal stability and lack red‐light, which restrict their applications in high‐power and high‐color‐rendering‐index solid‐state lighting. YAG glass‐ceramics provide an efficient way to resolve these problems. Herein, novel YAG‐embedded calcium bismuth borate glass‐ceramics (YAG‐GCs) with Eu3+ doping were prepared using a rapid melt quenching technique. The precursor glass exhibits superior YAG refractive index matching and high transmittance. Differential scanning calorimeter simulations verify YAG particles react with the precursor glass. The degree of YAG erosion is slight but monotonously increases with the co‐sintering temperature from 640 to 700°C. The erosion products probably contain YAB (Al3Y(BO3)4), Al3Eu(BO3)4, Bi24B2O39, and Ca12Al14O33 phases, and the Bi ion valence state is maintained during the reaction process. The energy transfer from Ce3+ to Eu3+ is suppressed. The YAG‐GC PL intensities monotonously increase as the co‐sintering temperature decrease from 640 to 700°C and the YAG content increase from 2.5 to 7 wt.%. The optical parameters of a WLEDs packed by YAG‐GCs and blue chips are a luminous efficiency of 105.3 lm/W, correlated color temperature of 3940 K and color rendering index of 70.1. The as‐prepared YAG‐GCs are promising candidates for high‐power, warm WLEDs due to their superior thermal stability, high quantum efficiency, and low cost. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses articles in the issue on topics including China Geological Survey, and Technological Basic Research Special Project of the Ministry of Science and Technology of China.

In ischemic stroke, neutrophils are the first-line peripheral immune cells infiltrating the brain tissue to form neutrophil extracellular traps (NETs). The present study aimed to investigate the role of neuronal cold-inducible RNA-binding protein (CIRP) in promoting NETs-induced brain endothelial barrier destruction and cerebral edema after ischemic stroke. We found that the expression of NETs and neuronal CIRP in the penumbra increased at 6 hours after transient middle cerebral artery occlusion (tMCAO) and increased significantly at 24 hours, reaching a peak at 3 days. NETs degradation or CIRP inhibition can alleviate the leakage of brain endothelial barrier and reverse the decreased expression of tight junction proteins (zonula occludens-1, claudin-5 and occludin) in tMCAO mice. Oxygen-glucose deprivation/reperfusion treated primary neurons or recombinant CIRP could induce NETs formation via TLR4/p38 signaling pathway in vitro. Transcription factor specificity protein 1 (sp1) was responsible for the increased neuronal CIRP expression and the inhibition of sp1 could suppress the increased CIRP expression, reduce NETs formation, and diminish brain endothelial barrier leakage in tMCAO mice. We also found the upregulated CIRP level was associated with severe cerebral edema in patients with acute ischemic stroke. In conclusion, the increased expression of transcription factor sp1 after ischemic stroke can lead to elevated CIRP expression and release from the neurons, which subsequently interacts with neutrophils and promotes NETs formation, resulting in brain endothelial barrier destruction and cerebral edema.