Episode of intense chemical weathering during the termination of the 635 Ma Marinoan glaciation.

Cryogenian (∼720-635 Ma) global glaciations (the snowball Earth) represent the most extreme ice ages in Earth's history. The termination of these snowball Earth glaciations is marked by the global precipitation of cap carbonates, which are interpreted to have been driven by intense chemical weathering on continents. However, direct geochemical evidence for the intense chemical weathering in the aftermath of snowball glaciations is lacking. Here, we report Mg isotopic data from the terminal Cryogenian or Marinoan-age Nantuo Formation and the overlying cap carbonate of the basal Doushantuo Formation in South China. A positive excursion of extremely high δ26Mg values (+0.56 to +0.95)-indicative of an episode of intense chemical weathering-occurs in the top Nantuo Formation, whereas the siliciclastic component of the overlying Doushantuo cap carbonate has significantly lower δ26Mg values (<+0.40), suggesting moderate to low intensity of chemical weathering during cap carbonate deposition. These observations suggest that cap carbonate deposition postdates the climax of chemical weathering, probably because of the suppression of carbonate precipitation in an acidified ocean when atmospheric CO2 concentration was high. Cap carbonate deposition did not occur until chemical weathering had consumed substantial amounts of atmospheric CO2 and accumulated high levels of oceanic alkalinity. Our finding confirms intense chemical weathering at the onset of deglaciation but indicates that the maximum weathering predated cap carbonate deposition.

Construction and validation of nomogram prediction model for risk of acute heart failure in patients with acute exacerbation of chronic obstructive pulmonary disease.

To investigate the influencing factors of in-hospital acute heart failure (AHF) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD), and to construct and validate a risk prediction nomogram model. Three Hundred Thirty patients with AECOPD admitted to our hospital from June 2020 to June 2023 were retrospectively analyzed as a training set for the construction of the model. Three Hundred Twenty-five AECOPD patients admitted to the Second People's Hospital of Hefei from 2006 to June 2023 were also collected as the validation set for the validation of the model. A nomogram model was constructed to predict the risk of nosocomial AHF in patients with AECOPD, and C-index and receiver operating characteristic curve were drawn to assess the predictive predictive efficacy of the model. Model fit was evaluated by Hosmer-Lemeshow test, calibration curve was drawn to evaluate the calibration of the model; decision curve was drawn to analyze the net benefit rate of this nomogram model. Multivariate logistic regression analysis indicated that body mass index, mmRC grade, neutrophils, lymphocytes, hemoglobin, creatinine, PO2, PCO2, and Homocysteine were independent risk factors for in-hospital AHF in patients with AECOPD. To construct a nomogram model for risk prediction of in-hospital AHF in patients with AECOPD. The C-index of the training set was 0.949 (95% CI: 0.91-0.961); the C-index of the validation set was 0.936 (95% CI: 0.911-0.961) suggesting good model discrimination. The receiver operating characteristic curve calculated area under curve for the training set was 0.949 (95% CI: 0.928-0.97); area under curve for the validation set was 0.936 (95% CI: 0.91-0.961) suggesting good model accuracy. The results of Hosmer-Lemeshoe goodness-of-fit test and calibration curve analysis showed that the calibration curve of this nomogram model was close to the ideal curve. The clinical decision curve also showed good clinical net benefit of the nomogram model. Body mass index, mmRC grade, neutrophils, lymphocytes, hemoglobin, creatinine, PO2, PCO2, and Homocysteine are risk factors for in-hospital AHF in AECOPD patients, and nomogram models constructed based on the above factors have some predictive value for in-hospital AHF in AECOPD patients. It is also vital for nursing staff to strengthen nursing care.

[Differences between oral and intestinal microorganisms of 860 children aged 1-6 years in Nanjing city].

PURPOSE: To explore the differences between oral and intestinal microorganisms of 860 children aged 1-6 years in Nanjing city. METHODS: Eight hundred and sixty children aged 1-6 years who met the inclusion criteria were enrolled. 860 saliva samples and equivalent stool samples were collected. Microbial DNA was extracted and amplified using PCR. High-throughput sequencing was performed using Miseq sequencer, and bioinformatics analysis was performed to compare the differences of oral and intestinal microflora. SPSS 20.0 software package was used to perform the statistical analysis. RESULTS: At phylum level, Bacteroidetes (39.98%), Proteobacteria (25.32%) and Firmicutes (21.78%) were the most common microbes in oral cavity, while Firmicutes (45.21%) and Bacteroidetes (37.21%) were the most abundant microbes in the gut. At genus level, the top three microbes in the oral cavity included Prevotella(26.11%), Neisseria (12.39%), Porphyromonas(10.13%), while the top three microbes in the gut included Bacteroidetes(20.11%), Prevotella (9.13%), and Faecalibacterium (5.13%). There were significant alpha and beta differences in oral and intestinal microbial diversity. CONCLUSIONS: Bacteroidetes and Proteobacteria are the dominant species in the oral cavity, while Firmicutes and Bacteroidetes are the dominant species in the gut. There are significant differences in species composition and abundance between oral and intestinal microorganisms.

[Research on the pathogeny of black tooth stain and association between black tooth stain and primary dentition caries in children].

PURPOSE: To investigate the related factors of black tooth stain in primary teeth of 3~5 years old children and caries status of primary dentition in these children. METHODS: From December 2019 to August 2020, 182 3~5 years old children with black tooth stain and 200 children without pigmentation were investigated by oral examination and questionnaire survey to their guardians, while caries status , distribution range of the pigment, factors associated with black tooth stain were evaluated. SPSS 20.0 software package was used for data analysis. RESULTS: Children with black tooth stain had fewer dental caries. The lingual surfaces of the mandibular anterior teeth were the most affected sites. Factors associated with black tooth stain were foods with soy sauce and brushing teeth with parents' help. CONCLUSIONS: There is a negative correlation between the occurrence of primary dentition caries and blacktooth stain, but there is no significant correlation between formation of black tooth stain and most environmental factors.

Iridium-catalyzed enantioselective alkynylation and kinetic resolution of alkyl allylic alcohols.

Herein, we report an efficient kinetic resolution of alkyl allylic alcohols enabled by an iridium-catalyzed enantioselective alkynylation of alkyl allylic alcohols with potassium alkynyltrifluoroborates. A wide range of chiral 1,4-enynes bearing various functional groups and unreacted enantioenriched allylic alcohols were obtained with excellent enantioselectivities and high kinetic resolution performance (s-factor up to 922). Additionally, this method is particularly effective for preparing some useful optically pure alkyl allylic alcohols, such as the key components towards the synthesis of prostaglandins and naturally occurring matsutakeols, which are difficult to access via other asymmetric reactions. Mechanistic studies revealed that the efficient kinetic resolution might be due to the significant distinction of the η 2-coordination between the (R)- and (S)-allylic alcohols with the iridium/(phosphoramidite, olefin) complex.

Optical resolution of 1,16-dihydroxytetraphenylene by chiral gold(iii) complexation and its applications as chiral ligands in asymmetric catalysis.

We report herein a novel approach involving optical resolution of (±)-1,16-dihydroxytetraphenylene (DHTP) by chiral gold(iii) complexation. This method features several key advantages, i.e., recyclability of chiral resolution reagents, feasibility of scaling up to gram quantities, and operational simplicity. On the basis of this method, which led to optically pure DHTP, a library of 2,15-diaryl (S)-DHTPs and several (S)-DHTP-derived phosphoramidite ligands were synthesized. Finally, the superior performance of a (S)-DHTP phosphoramidite ligand was demonstrated by efficient iridium-catalyzed asymmetric allylic alkynylation reactions.

[Analysis of the effect of improved ART with high-intensity glass ionomer cement in the treatment of primary caries in children].

PURPOSE: To investigate the effect of improved atraumatic restorative treatment(ART) with high-strength glass ionomer cement in the treatment of primary caries in children. METHODS: From August 2018 to May 2019, 262 children with primary tooth caries who were treated in Children's Hospital of Nanjing Medical University were selected into our study, prospectively. The children were divided into two groups, randomly: ART group (131 cases, 177 teeth) and control group (131 cases, 178 teeth). Children in the control group were treated with conventional cavity preparation and composite resin filling, while those in the ART group were treated with improved high-intensity glass ionomer. The curative effect and satisfaction degree were compared between the two groups. SPSS 19.0 software package was used for data analysis. RESULTS: The overall curative effect in the ART group was better than that of the control group. The cooperation degree of the 2~4 years old children in the ART group was significantly higher than that of the control group(P<0.05). The cooperation degree of the 5 years old children between the two groups had no significant differences(P>0.05). Both groups of children accepted 12 months of follow-up. Three months after treatment, the rate of secondary caries in the ART group was significantly lower than that in the control group, but it was not statistically significant(P>0.05). Six and 12 months after treatment, the rate of secondary caries in the ART group were significantly lower than that in the control group(P<0.05), and the satisfaction of parents in the ART group was significantly higher than that in the control group (P<0.05). CONCLUSIONS: Improved ART with high-intensity glass ionomer cement is more likely accepted by children and their parents, with more willing to accept and cooperate with the treatment. Not only is it easy to operate, but also has a reliable curative effect in children.

Characterization of the complete chloroplast genome of the Solanum tuberosum L. cv. Atlantic (Solanaceae).

Potato (Solanum tuberosum L.), a species of the family Solanaceae, is the fourth most important food crop worldwide. Solanum tuberosum L. cv. Atlantic, a main fried special potato, has a dry matter content of 19%-23% and a starch content of 16.26% in the tuber. In order to support more molecular data for the taxony of S. tuberosum, the complete chloroplast (cp) genome sequence of S. tuberosum L. cv. Atlantic was determined using next-generation sequencing. In leaves, the chloroplast genome accounts for 5.49% of the total genome. The entire cp genome was determined to be 155,296 bp in length. It contained large single-copy (LSC) and small single-copy (SSC) regions of 85,737 and 18,373 bp, respectively, which were separated by a pair of 25,593 bp inverted repeat (IR) regions. The genome contained 132 genes, including 87 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The overall GC content of the genome is 37.9%. A phylogenetic tree reconstructed by 64 chloroplast genomes reveals that S. tuberosum L. cv. Atlantic is most closely related to Solanum tuberosum L. cv. Desiree.

Characterization of the complete chloroplast genome of the Solanum tuberosum L. cv. Favorita (Solanaceae).

Potato (Solanum tuberosum L.), a species of the family Solanaceae, is the fourth most important food crop worldwide. Solanum tuberosum L. cv. Favorita is a long oval, smooth, yellowish-skinned potato variety with green and plump leaves. It has a dry matter content of 17.7% and starch content of 12.4-14.01% in the tuber. In order to support more genetic data for the taxonomy of S. tuberosum, the complete chloroplast (cp) genome sequence of S. tuberosum L. cv. Favorita was determined using next-generation sequencing. In leaves, the chloroplast genome accounts for 5.17% of the total genome. The entire cp genome was determined to be 155,296 bp in length. It contained large single-copy (LSC) and small single-copy (SSC) regions of 85,737 and 18,373 bp, respectively, which were separated by a pair of 25,593 bp inverted repeat (IR) regions. The genome contained 132 total genes, including 87 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The overall GC content of the genome is 37.9%. A phylogenetic tree reconstructed by 60 chloroplast genomes reveals that S. tuberosum L. cv. Favorita is most closely related to S. tuberosum L. cv. Desiree and S. tuberosum L. cv. Atlantic.

Effects of natural ingredients on the shelf life of chicken seasoning.

The effects of the natural ingredients Angelica sinensis (AS) and Codonopsis pilosula (CP) on the shelf life of chicken seasoning were investigated. Color differences and sensory evaluation were used to indicate sensory differences. Changes in volatiles were monitored. The rate of increase in the color value a* of the AS and CP samples was lower than that in the control. Rancid flavor appeared later in the AS and CP samples than in the control. The levels of aldehydes, ketones, and alkenes increased during storage. A kinetic model was built based on the proportion of aldehydes (main marker), to predict shelf life. The predicted shelf life at room temperature was 60 days for the control, 114 days for AS, and 89 days for CP. The shelf life of chicken seasoning could be prolonged with AS and CP. This kinetic model can be used to predict the shelf life of chicken seasoning.

Indole diketopiperazines from endophytic Chaetomium sp 88194 induce breast cancer cell apoptotic death.

Diketopiperazines are important secondary metabolites of the fungi with variety bioactivities. Several species belonging to genus Chaetomium produce compounds of this class, such as chetomin. To identify new antitumor agents, secondary metabolites of fungus Chaetomium sp 88194 were investigated and three new indole diketopiperazines, Chaetocochins G (1), Oidioperazines E (2) and Chetoseminudin E (3), along with two known compounds Chetoseminudins C (4) and N-acetyl-ß-oxotryptamine (5), were obtained. Chaetocochins G and Chetoseminudin E were recrystallized in CHCl3 containing a small amount of MeOH, and their structures with absolute configuration were established by spectroscopic data interpretation and single-crystal X-ray diffraction analysis. The absolute configuration of Oidioperazines E was defined by comparing of experimental and calculated electronic circular dichroism spectra. These isolates were also evaluated the anticancer activity, and Chaetocochins G displayed more potent cytotoxicity in MCF-7 cells than the common chemotherapeutic agent (5-fluorouracil) associated with G2/M cell cycle arrest. More importantly, Chaetocochins G induced cell apoptotic death via caspase-3 induction and proteolytic cleavage of poly (ADP-ribose) polymerase, concomitantly with increased Bax and decreased Bcl-2 expression. Our findings suggested that indole diketopiperazines from endophytic Chaetomium sp 88194 may be potential resource for developing anti-cancer reagents.