Bayan Obo ore deposit is the largest rare-earth element（REE） resource,and the second largest niobium（Nb） resource in the world.Due to the complicated element/mineral compositions and involving ...several geological events,the REE enrichment mechanism and genesis of this giant deposit still remains intense debated.The deposit is hosted in the massive dolomite,and nearly one hundred carbonatite dykes occur in the vicinity of the deposit.The carbonatite dykes can be divided into three types from early to late：dolomite,co-existing dolomite-calcite and calcite type,corresponding to different evolutionary stages of carbonatite magmatism based on the REE and trace element data.The latter always has higher REE content.The origin of the ore-hosting dolomite at Bayan Obo has been addressed in various models,ranging from a normal sedimentary carbonate rocks to volcano-sedimentary sequence,and a large carbonatitic intrusion.More geochemical evidences show that the coarse-grained dolomite represents a Mesoproterozoic carbonatite pluton and the fine-grained dolomite resulted from the extensive REE mineralization and modification of the coarse-grained variety.The ore bodies,distributed along an E-W striking belt,occur as large lenses and underwent more intense fluoritization and fenitization.The first episode mineralization is characterized by disseminated mineralization in the dolomite.The second or main-episode is banded and/or massive mineralization,cut by the third episode consisting of aegirinerich veins.Various dating methods gave different mineralization ages at Bayan Obo,resulting in long and hot debates.Compilation of available data suggests that the mineralization is rather variable with two peaks at～1400 and 440 Ma.The early mineralization peak closes in time to the intrusion of the carbonatite dykes.A significant thermal event at ca.440 Ma resulted in the formation of late-stage veins with coarse crystals of REE minerals.Fluids involving in the REE-Nb-Fe mineralization at Bayan Obo might be REE-F-C02-NaCI-H20 system.The presence of REE-carbonates as an abundant solid in the ores shows that the original ore-forming fluids are very rich in REE,and therefore,have the potential to produce economic REE ores at Bayan Obo.the Bayan Obo deposit is a product of mantle-derived carbonatitic magmatism at ca.1400 Ma,which was likely related to the breakup of Columbia.Some remobilization of REE occurred due to subduction of the Palaeo-Asian oceanic plate during the Silurian,forming weak vein-like mineralization.
Background/Aims. It is known that chronic low-grade inflammation contributes to the initiation and development of both diabetes and diabetic nephropathy (DN), so we designed this study to investigate ...the role of P2X7R and NLRP3 inflammasome in DN pathogenesis and the antagonistic effects of artificially cultivated Ophiocordyceps sinensis (ACOS). Methods. A rat model of DN caused by high-fat-diet feeding and low-dose streptozotocin injection and a mouse podocyte injury model induced by high-glucose (HG) stimulation were established, and the intervention effects of ACOS on them were observed. The biological parameters of serum and urine and the pathological manifestations of kidney tissue were examined. The expression of mRNA and protein of P2X7R and NLRP3 inflammasome (NLRP3, ASC, and caspase-1) and downstream effectors (IL-1β and IL-18), as well as podocyte-associated molecules, was determined by real-time quantitative PCR and Western blot assay, respectively. Results. The DN rats showed to have developed insulin resistance, elevated fasting blood glucose, increased urinary protein excretion, and serum creatinine level as well as corresponding glomerular pathological alterations including podocyte damages. ACOS significantly antagonized the above changes. The experiments in vivo and in vitro both displayed that the mRNA and protein expression of P2X7R, NLRP3, ASC, caspase1 (procaspase-1 mRNA in the gene level and active caspase-1 subunit P10 in the protein level), IL-1β, and IL-18 was significantly upregulated and the mRNA and protein expression of podocyte-associated molecules was significantly changed (downregulation of nephrin, podocin, and WT-1 expression and upregulation of desmin expression) indicating podocyte injury in the kidney tissue of DN rats and in the HG-stressed mouse podocytes, respectively. ACOS also significantly antagonized all the above changes. Conclusion. Our research work suggests that P2X7R and NLRP3 inflammasome are involved in the pathogenesis of DN, and ACOS can effectively inhibit the high expression of P2X7R and the activation of NLRP3 inflammasome, which may contribute to the therapeutic effects of Ophiocordyceps sinensis.
We demonstrate the existence of P−V criticality of the topological Hořava-Lifshitz (HL) black holes with a spherical horizon (k=1) in the extended phase space. With the electric charge, we find that ...the critical behaviors of the HL black hole are nearly the same as those of a van der Waals (VdW) system. For the uncharged case, the HL black hole has a peculiar P−V criticality. The critical behavior is completely controlled by a parameter ε, but not the temperature T. When ε is larger than a critical value εc, no matter what the temperature is, there will be the first-order phase transition. Moreover, we find that there is an infinite number of critical points which form a “critical curve.” As far as we know, this is the first time to find this kind of peculiar P−V criticality.
The research work in the past years showed that detection of phospholipase A2 receptor (PLA2R) antigen and its dominant IgG4 autoantibody in glomerular deposits of patients with membranous ...nephropathy (MN) was useful for the differentiation between primary MN (PMN) and secondary MN (SMN), but so far such research data from large Chinese patient series is little. Here, we are going to report a research work in a Chinese cohort.
This study enrolled 179 patients with PMN, 40 patients with membranous lupus nephritis (LN-MN), 26 patients with hepatitis B virus-associated MN (HBV-MN), 2 patients with malignancy-associated MN (M-MN) and one patient with IgG4-related MN (IgG4-MN). PLA2R and IgG subclasses in glomerular deposits of these patients were examined by immunofluorescence and/or immunohistochemical staining, and the potential value of the above examinations for differential diagnosis of PMN and SMN was evaluated.
Glomerular PLA2R deposition was present in 92.2% patients with PMN and 7.7% patients with HBV-MN, but none of the patients with LN-MN. Predominant/codominant IgG4 deposition was found in 93.3% patients with PMN and 11.5% patients with HBV-MN, but none of the patients with LN-MN. The two M-MN patients both had glomerular PLA2R and predominant/codominant IgG4 deposition. The one IgG4-MN patient had deeply staining IgG4 but no PLA2R in glomeruli.
The glomerular PLA2R and predominant/codominant IgG4 deposition is frequently observed in Chinese patients with PMN. Immunofluorescence and immunohistochemical staining of renal biopsy tissue for detection of glomerular PLA2R and IgG subclasses deposition can help to distinguish PMN from LN-MN and most of HBV-MN.
Inflammatory mechanisms play important roles in intracerebral hemorrhage (ICH) and have been linked to the development of stroke-associated pneumonia (SAP). The neutrophil-to-lymphocyte ratio (NLR), ...systemic immune-inflammation index (SII), platelet-to-lymphocyte ratio (PLR) and systemic inflammation response index (SIRI) are inflammatory indexes that influence systemic inflammatory responses after stroke. In this study, we aimed to compare the predictive value of the NLR, SII, SIRI and PLR for SAP in patients with ICH to determine their application potential in the early identification of the severity of pneumonia.
Patients with ICH in four hospitals were prospectively enrolled. SAP was defined according to the modified Centers for Disease Control and Prevention criteria. Data on the NLR, SII, SIRI and PLR were collected at admission, and the correlation between these factors and the clinical pulmonary infection score (CPIS) was assessed through Spearman's analysis.
A total of 320 patients were enrolled in this study, among whom 126 (39.4%) developed SAP. The results of the receiver operating characteristic (ROC) analysis revealed that the NLR had the best predictive value for SAP (AUC: 0.748, 95% CI: 0.695-0.801), and this outcome remained significant after adjusting for other confounders in multivariable analysis (RR=1.090, 95% CI: 1.029-1.155). Among the four indexes, Spearman's analysis showed that the NLR was the most highly correlated with the CPIS (r=0.537, 95% CI: 0.395-0.654). The NLR could effectively predict ICU admission (AUC: 0.732, 95% CI: 0.671-0.786), and this finding remained significant in the multivariable analysis (RR=1.049, 95% CI: 1.009-1.089, P=0.036). Nomograms were created to predict the probability of SAP occurrence and ICU admission. Furthermore, the NLR could predict a good outcome at discharge (AUC: 0.761, 95% CI: 0.707-0.8147).
Among the four indexes, the NLR was the best predictor for SAP occurrence and a poor outcome at discharge in ICH patients. It can therefore be used for the early identification of severe SAP and to predict ICU admission.
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•Amorphous TiO2/BiOBr hybrids are fabricated under microwave irradiation.•The coupling of TiO2 on the {001} faces of BiOBr facilitates the electrons transfer.•BiOBr inhibits the ...growth of amorphous TiO2 nanoparticles via the in situ route.•The defect levels in amorphous TiO2 act as effective electron acceptor for BiOBr.•The photocatalytic activity of 15%TiO2/BiOBr is 3.4 times that of pristine BiOBr.
Facets coupled BiOBr with amorphous TiO2 composite photocatalysts are synthesized via an in situ direct growth approach under microwave irradiation. XRD, SEM and HRTEM characterizations indicate that the heterointerface between BiOBr and amorphous TiO2 occurs mainly on the {001} facets of BiOBr. BET and TEM verify that the heterojunctions possess higher specific surface areas and smaller amorphous TiO2 particle size than bare BiOBr and amorphous TiO2, exhibiting the inhibition function of BiOBr on the growth of TiO2 particles. XPS verifies the interaction between the two components. The degradation of methyl orange (MO) and phenol are used as the objective reaction to evaluate the photocatalytic activity of the as-prepared samples. The reaction rate constant of 15% TiO2/BiOBr composite is 3.4 times greater than that of pure BiOBr, which is attributed to its higher surface area, and efficient separation of photo-generated electron–hole pairs between BiOBr and amorphous TiO2.
In the present study, the contents of amino acids, fatty acids, polysaccharides, polyphenols, and flavonoids were compared in tartary buckwheat bran and flour before and after baking. The results ...showed that the contents of all the bioactive compounds in raw tartary buckwheat bran were higher than that in raw tartary buckwheat flour, except for polysaccharides. Thermal treatment caused a significant decrease in the contents of fatty acids, polysaccharides, and polyphenols in both tartary buckwheat bran and flour. The contents of amino acids and total flavonoids in tartary buckwheat bran decreased after baking, but their contents increased in baked tartary buckwheat flour. High-performance liquid chromatography analysis results showed that the rutin content decreased in baked tartary buckwheat bran, whereas significantly increased by 68.92% in baked tartary buckwheat flour (p < .01). These results suggest that tartary buckwheat bran and flour should be processed differently according to the target products.
Members of sirtuin family regulate multiple critical biological processes, yet their role in carcinogenesis remains controversial. To investigate the physiological functions of SIRT2 in development ...and tumorigenesis, we disrupted Sirt2 in mice. We demonstrated that SIRT2 regulates the anaphase-promoting complex/cyclosome activity through deacetylation of its coactivators, APCCDH1 and CDC20. SIRT2 deficiency caused increased levels of mitotic regulators, including Aurora-A and -B that direct centrosome amplification, aneuploidy, and mitotic cell death. Sirt2-deficient mice develop gender-specific tumorigenesis, with females primarily developing mammary tumors, and males developing more hepatocellular carcinoma (HCC). Human breast cancers and HCC samples exhibited reduced SIRT2 levels compared with normal tissues. These data demonstrate that SIRT2 is a tumor suppressor through its role in regulating mitosis and genome integrity.
► Hyperacetylation of adaptor protein CDH1 and CDC20 inhibits APC/C activity ► SIRT2 positive regulates APC/C activity through deacetylation of CDH1 and CDC20 ► Expression of SIRT2 is reduced in human breast and liver cancers ► SIRT2 deficiency in mice causes mitotic cell death, genetic instability, and tumorigenesis
Cuspy shadow was first reported for hairy rotating black holes, whose metrics deviate significantly from the Kerr one. The non-smooth edge of the shadow is attributed to a transition between ...different branches of unstable but bounded orbits, known as the fundamental photon orbits, which end up at the light rings. In searching for a minimal theoretical setup to reproduce such a salient feature, in this work, we devise a toy model with axisymmetry, a slowly rotating Kerr black hole enveloped by a thin slowly rotating dark matter shell. Despite its simplicity, we show rich structures regarding fundamental photon orbits explicitly in such a system. We observe two disconnected branches of unstable spherical photon orbits, and the jump between them gives rise to a pair of cusps in the resultant black hole shadow. Besides the cuspy shadow, we explore other intriguing phenomena when the Maxwell construction cannot be established. We find that it is possible to have an incomplete arc of Einstein rings and a “fractured” shadow. The potential astrophysical significance of the corresponding findings is addressed.
Summary
Plastids and mitochondria are endosymbiotic organelles that store genetic information. The genomes of these organelles generally exhibit contrasting patterns regarding genome architecture and ...genetic content. However, they have similar genetic features in Selaginellaceae, and little is known about what causes parallel evolution. Here, we document the multipartite plastid genomes (plastomes) and the highly divergent mitochondrial genomes (mitogenomes) from spikemoss obtained by combining short‐ and long‐reads. The 188‐kb multipartite plastome has three ribosomal operon copies in the master genomic conformation, creating the alternative subgenomic conformation composed of 110‐ and 78‐kb subgenomes. The long‐read data indicated that the two different genomic conformations were present in almost equal proportions in the plastomes of Selaginella nipponica. The mitogenome of S. nipponica was assembled into 27 contigs with a total size of 110 kb. All contigs contained directly arranged repeats at both ends, which introduced multiple conformations. Our results showed that plastomes and mitogenomes share high tRNA losses, GC‐biased nucleotides, elevated substitution rates and complicated organization. The exploration of nuclear‐encoded organelle DNA replication, recombination and repair proteins indicated that, several single‐targeted proteins, particularly plastid‐targeted recombinase A1, have been lost in Selaginellaceae; conversely, the dual‐targeted proteins remain intact. According to the reported function of recombinase A1, we propose that the plastomes of spikemoss often fail to pair homologous sequences during recombination, and the dual‐targeted proteins play a key role in the convergent genetic features of plastomes and mitogenomes. Our results provide a distinctive evolutionary pattern of the organelle genomes in Selaginellaceae and evidence of their convergent evolution.
Significance Statement
Plastid and mitochondrial genomes usually exhibit contrasting patterns of conserved plastid genomes and diverged mitochondrial genomes. Here, we document that both the organelle genomes in Selaginellaceae exhibit parallel genetic features. In addition, we explore which factor is likely responsible for the unconventional features of plastid genomes, and convergent evolution of the two organelle genomes. This study helps explain the distinctive evolutionary patterns of organelle genomes in Selaginellaceae, and advance our current understanding of organelle genomics.
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