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We present precise photometric estimates of stellar parameters, including effective temperature, metallicity, luminosity classification, distance, and stellar age, for nearly 26 million stars using the methodology developed in the first paper of this series, based on the stellar colors from the Stellar Abundances and Galactic Evolution Survey (SAGES) Data Release 1 and Gaia Early Data Release 3. The optimal design of stellar-parameter sensitive uv filters by SAGES has enabled us to determine photometric-metallicity estimates down to −3.5, similar to our previous results with the SkyMapper Southern Survey (SMSS), yielding a large sample of over five million metal-poor ([Fe/H] ≤ −1.0) stars and nearly one million very metal-poor ([Fe/H] ≤ −2.0) stars. The typical precision is around 0.1 dex for both dwarf and giant stars with [Fe/H] > −1.0, and 0.15–0.25/0.3–0.4 dex for dwarf/giant stars with [Fe/H] < −1.0. Using the precise parallax measurements and stellar colors from Gaia, effective temperature, luminosity classification, distance, and stellar age are further derived for our sample stars. This huge data set in the Northern sky from SAGES, together with similar data in the Southern sky from SMSS, will greatly advance our understanding of the Milky Way, in particular its formation and evolution. [ABSTRACT FROM AUTHOR]

The most massive and shortest-lived stars dominate the chemical evolution of the pre-galactic era. On the basis of numerical simulations, it has long been speculated that the mass of such first-generation stars was up to several hundred solar masses1–4. The very massive first-generation stars with a mass range from 140 to 260 solar masses are predicted to enrich the early interstellar medium through pair-instability supernovae (PISNe)5. Decades of observational efforts, however, have not been able to uniquely identify the imprints of such very massive stars on the most metal-poor stars in the Milky Way6,7. Here we report the chemical composition of a very metal-poor (VMP) star with extremely low sodium and cobalt abundances. The sodium with respect to iron in this star is more than two orders of magnitude lower than that of the Sun. This star exhibits very large abundance variance between the odd- and even-charge-number elements, such as sodium/magnesium and cobalt/nickel. Such peculiar odd–even effect, along with deficiencies of sodium and α elements, are consistent with the prediction of primordial pair-instability supernova (PISN) from stars more massive than 140 solar masses. This provides a clear chemical signature indicating the existence of very massive stars in the early universe.The chemical composition of the Galactic halo star J1010+2358 shows extremely low sodium and cobalt abundances, different from most other halo stars, indicative of a very metal-poor star being seeded with elements from a pair-instability supernova. [ABSTRACT FROM AUTHOR]

Background: To investigate the use of flipped classroom pedagogy based on "Internet plus" in teaching viral hepatitis in the lemology course during the COVID-19 epidemic. Methods: This study included students from the clinical medicine general practitioner class at Nanjing Medical University's Kangda College, with the observation group consisting of 67 students from the 2020–2021 school year and the control group consisting of 70 students from the 2019–2020 school year. The observation group used "Internet plus" flipped classroom pedagogy, while the control group used conventional offline instruction. The theory course and case analysis ability scores from the two groups were compared and analyzed, and questionnaire surveys were administered to the observation group. Result: After the flipped classroom, the observation group had significantly higher theoretical test scores (38.62 ± 4.52) and case analysis ability scores (21.08 ± 3.58) than the control group (37.37 ± 2.43) (t = 2.024, P = 0.045) and (19.16 ± 1.15) (t = 4.254, P < 0.001), respectively. The questionnaire survey in the observation group revealed that the "Internet plus" flipped classroom pedagogy approach can help enhance students' enthusiasm to learn, clinical thinking ability, practical application ability, and learning efficiency, with satisfaction rates of 81.7%, 85.0%, 83.3%, and 78.8%, respectively; 89.4% of students expressed hope that whenever physical classes resumed, the offline courses could be combined with this pedagogy approach. Conclusion: The use of the "Internet plus" flipped classroom pedagogy technique for teaching viral hepatitis in a lemology course boosted students' theory learning ability as well as their case analysis ability. The majority of students were pleased with this type of instruction and hoped that whenever physical classes resumed, the offline courses may be integrated with the "Internet plus" flipped classroom pedagogical approach. [ABSTRACT FROM AUTHOR]

Aims Phylogenetic diversity metrics can discern the relative contributions of ecological and evolutionary processes associated with the assembly of plant communities. However, the magnitude of the potential variation associated with phylogenetic methodologies, and its effect on estimates of phylogenetic diversity, remains poorly understood. Here, we assess how sources of variation associated with estimates of phylogenetic diversity can potentially affect our understanding of plant community structure for a series of temperate forest plots in China. Methods In total, 20 forest plots, comprising of 274 woody species and 581 herbaceous species, were surveyed and sampled along an elevational gradient of 2800 m on Taibai Mountain, China. We used multi-model inference to search for the most parsimonious relationship between estimates of phylogenetic diversity and each of four predictors (i.e. type of phylogenetic reconstruction method, phylogenetic diversity metric, woody or herbaceous growth form and elevation), and their pairwise interactions. Important Findings There was no significant difference in patterns of phylogenetic diversity when using synthesis-based vs. molecular-based phylogenetic methods. Results showed that elevation, the type of phylogenetic diversity metric, growth form and their interactions, accounted for >44% of the variance in our estimates of phylogenetic diversity. In general, phylogenetic diversity decreased with increasing elevation; however, the trend was weaker for herbaceous plants than for woody plants. Moreover, the three phylogenetic diversity metrics showed consistent patterns (i.e. clustered) across the elevational gradient for woody plants. For herbaceous plants, the mean pairwise distance showed a random distribution over the gradient. These results suggest that a better understanding of temperate forest community structure can be obtained when estimates of phylogenetic diversity include methodological and environmental sources of variation. [ABSTRACT FROM AUTHOR]

Background: Escherichia coli are mostly commensals but also contain pathogenic lineages. It is largely unclear whether the commensal E. coli as the potential origins of pathogenic lineages may consist of monophyletic or polyphyletic populations, elucidation of which is expected to lead to novel insights into the associations of E. coli diversity with human health and diseases. Methods: Using genomic sequencing and pulsed field gel electrophoresis (PFGE) techniques, we analyzed E. coli from the intestinal microbiota of three groups of healthy individuals, including preschool children, university students, and seniors of a longevity village, as well as colorectal cancer (CRC) patients, to probe the commensal E. coli populations for their diversity. Results: We delineated the 2280 fresh E. coli isolates from 185 subjects into distinct genome types (genotypes) by PFGE. The genomic diversity of the sampled E. coli populations was so high that a given subject may have multiple genotypes of E. coli, with the general diversity within a host going up from preschool children through university students to seniors. Compared to the healthy subjects, the CRC patients had the lowest diversity level among their E. coli isolates. Notably, E. coli isolates from CRC patients could suppress the growth of E. coli bacteria isolated from healthy controls under nutrient-limited culture conditions. Conclusions: The coexistence of multiple E. coli lineages in a host may help create and maintain a microbial environment that is beneficial to the host. As such, the low diversity of E. coli bacteria may be associated with unhealthy microenvironment in the intestine and hence facilitate the pathogenesis of diseases such as CRC. [ABSTRACT FROM AUTHOR]

In this paper, we employed first-principle calculations to investigate the elastic properties, electronic properties and hardness of diamond and hexagonal W2B5 compounds under high pressure. The elastic properties were carried out to discuss the structural stability and the bond components of diamond and hexagonal W2B5. The electronic properties were presented to analysis the change of the bond components for W2B5. In addition, the hardness of these two crystals under high pressure was calculated by a semi-empirical method considering the role of metallic components and the effect of pressure on the hardness of diamond and hexagonal W2B5 was discussed. [ABSTRACT FROM AUTHOR]

Parkinson's disease is a neurodegenerative disorder characterized by mitochondrial dysfunction and oxidative stress. It is usually accompanied by an imbalance in mitochondrial dynamics and changes in mitochondrial morphology that are associated with impaired function. The objectives of this study were to identify the effects of rotenone, a drug known to mimic the pathophysiology of Parkinson's disease, on mitochondrial dynamics. Additionally, this study explored the protective effects of water-soluble Coenzyme Q10 (CoQ10) against rotenone-induced cytotoxicity in murine neuronal HT22 cells. Our results demonstrate that rotenone elevates protein expression of mitochondrial fission markers, Drp1 and Fis1, and causes an increase in mitochondrial fragmentation as evidenced through mitochondrial staining and morphological analysis. Water-soluble CoQ10 prevented mitochondrial dynamic imbalance by reducing Drp1 and Fis1 protein expression to pre-rotenone levels, as well as reducing rotenone treatment-associated mitochondrial fragmentation. Hence, water-soluble CoQ10 may have therapeutic potential in treating patients with Parkinson's disease. [ABSTRACT FROM AUTHOR]

The morphology and development of the flowers of Anemoclema glaucifolium were studied with light and scanning electron microscopy, and compared with related genera. In Anemoclema all floral organs are initiated in a spiral sequence, while phyllotaxis is irregular spiral. The young sepals are crescent-shaped, but the young stamens and carpels are hemispherical. The developmental sequence of the microspores in the stamens is centripetal, following the initiation sequence of the stamens. The mature ovule is anatropous and unitegmic. Our results support the inclusion of Anemoclema within Anemoneae based on the floral developmental and morphological features: carpels bearing one median fertile ovule and two or three lateral sterile ovules. Anemoclema also possesses traits that unify it with Clematis, that are lacking in Anemone: (1) centripetal anther maturation (vs. centrifugal or bidirectional), and (2) conspicuous appendage at the ventral base of the ovule funicle (vs. inconspicuous appendage). These characters support a close relationship to Clematis, which complement results from molecular inferences. [ABSTRACT FROM AUTHOR]

To observe the effects of Danshen aqueous extract (DSAE) on the cerebral tissue and nerve stem cells in cerebral ischemia reperfusion (CIR) rats. The model rats were prepared by occlusion of the middle cerebral artery for 2 h and then by reperfusion. They were randomly divided into five groups: a control group, an CIR group and three DSAE-treated groups. As compared with the sham control group, there was significant increase ( P < 0.05, P < 0.01) in the serum high-sensitivity C-reactive protein (hs-CRP) and interleukin-8 (IL-8) levels, interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α) levels, and IL-10 mRNA, TNF-α mRNA expression levels, function score, Infarct size, TUNEL + cell counts, cerebral transforming growth factor beta 1 (TGF-β1) positive expression and cerebral neuron specific enolase (NSE) levels, and decrease in fas-associated protein with death domain (FADD) and death-associated protein (Daxx) positive expression levels in the CIR group. Compared with CIR group, DSAE treatment dose-dependently significantly decreased serum hs-CRP, IL-8, IL-10, TNF-α levels, and IL-10 mRNA, TNF-α mRNA expression levels, function score, Infarct size, TUNEL + cell counts, cerebral TGF-β1 positive expression and cerebral NSE levels, and increase FADD and Daxx positive expression levels in the CIR + DSAE groups. Taken together, these results suggest that DSAE has a neuroprotective role in the CIR rats, which may be related to improvement of immunity function, proteins and genes expression. [ABSTRACT FROM AUTHOR]