13 research outputs found
Spin Density wave instability in a ferromagnet
Ferromagnetic (FM) and incommensurate spin-density wave (ISDW) states are an
unusual set of competing magnetic orders that are seldom observed in the same
material without application of a polarizing magnetic field. We report, for the
first time, the discovery of an ISDW state that is derived from a FM ground
state through a Fermi surface (FS) instability in FeGa. This was
achieved by combining neutron scattering experiments with first principles
simulations. Neutron diffraction demonstrates that FeGa is in an ISDW
state at intermediate temperatures and that there is a conspicuous re-emergence
of ferromagnetism above 360 K. First principles calculations show that the ISDW
ordering wavevector is in excellent agreement with a prominent nesting
condition in the spin-majority FS demonstrating the discovery of a novel
instability for FM metals; ISDW formation due to Fermi surface nesting in a
spin-polarized Fermi surface.Comment: 6 pages with 4 figures. Supplemental Materials Include
Isolation and characterization of a genotype 4 Hepatitis E virus strain from an infant in China
In the present study, a genotype 4 HEV strain was identified in the fecal specimen from a seven months old infant with no symptom of hepatitis in Shanghai Children's hospital. The full capsid protein gene (ORF2) sequence of this strain was determined by RT-PCR method. Sequence analysis based on the full ORF2 sequence indicated that this HEV strain shared the highest sequence identity (97.6%) with another human HEV strain isolated from a Japanese patient who was infected by genotype 4 HEV during traveling in Shanghai. Phylogenetic analysis showed that this genotype 4 HEV was phylogenetically far from the genotype 4 HEV strain that was commonly prevalent in Shanghai swine group, suggesting that this strain may not come from swine group and not involved in zoonotic transmission in this area
Penthorum chinense Pursh improves type 2 diabetes mellitus via modulating gut microbiota in db/db mice
Abstract Penthorum chinense Pursh (P. chinense) has been traditionally used as hepatoprotective food and medicine for hundreds of years due to its significant antioxidant and anti-inflammatory activities. However, the efficacy and mechanisms of action of P. chinense in type 2 diabetes mellitus were not fully understood. In this study, we found that P. chinense extract (PCP) supplementation resulted in reduced body weight and hyperglycemia, improved pancreatic tissue injury and insulin sensitivity, and decreased inflammatory cytokines expression in spontaneously diabetic db/db mice. 16S rRNA gene sequencing of fecal samples showed that PCP administration decreased the abundance of Firmicutes and increased the proportion of Bacteroidetes at the phylum level. Moreover, Muribaculum, Barnesiella, Prevotella, and Mucinivorans were enriched, with Desulfovibrio and Lactobacillus lowered at the genus level in db/db mice with PCP supplementation. These results suggested that PCP may ameliorate hyperglycemia, insulin resistance, and inflammation by remodeling the gut microbiota in db/db mice
Thermodynamic and Structural Characterization of Bulk Organic Matter in Chinese Silurian Shale: Experimental and Molecular Modeling Studies
Silurian
marine shale in Sichuan Basin is the most significant
target zone for shale gas resources in China. In this work, a combined
experimental and molecular simulation study was conducted to characterize
the thermodynamic and structural properties of the organic matter
in Silurian shale. Organic geochemistry experiments and Fourier transform
infrared (FTIR) spectroscopy were performed to provide structural
parameters for the main skeleton of the organic matter. A realistic
molecular model of the organic matter under typical reservoir conditions
was generated by molecular dynamics simulations based on the experimental
results and documented analytic data. The thermodynamic and structural
properties of the organic matter model were discussed in detail. Clear
correlations are found among geochemistry properties and structural
parameters of organic matter, independent of organic matter type and
maturity. Aromatic units in the organic matter are highly condensed,
and the interunit linkages are mainly short methylene groups. Ether
groups are the dominant oxygenated compounds, while aromatic sulfur
is the main form of organic sulfur. Reasonable consistencies are found
on results of compositions of the organic matter fractions and physical
density between simulated and available experimental data. The isothermal
compressibility and thermal expansion coefficient correspond to the
general range of a liquid. In addition to micropores, the organic
matter contains a large amount of ultramicropores, which contribute
a lot to the high porosity and specific surface area. The porous network
is highly connected with few dead pores. Interestingly, the introduction
of bitumen fractions has little effect on the spacing of polyaromatic
units, but it aggravates the relative slippage of polyaromatic units.
Also, separation of lighter compounds is observed in the structure.
The carbon dioxide molecules are closer to the oxygenated groups,
while the nitrogen molecules and methane molecules are closer to the
sulfur functional groups and nitrogen functional groups. This proposed
organic matter model can serve as a starting point for further theoretical
investigations on gas adsorption and transport mechanisms, representative
of the organic matter in Silurian shale at molecular scale
Ubiquitin-Specific Protease 3 Promotes Glioblastoma Cell Invasion and Epithelial–Mesenchymal Transition via Stabilizing Snail
Causal Effects of Specific Gut Microbiota on Chronic Kidney Diseases and Renal Function—A Two-Sample Mendelian Randomization Study
Background: Targeting the gut microbiota may become a new therapeutic to prevent and delay the progression of chronic kidney disease (CKD). Nonetheless, the causal relationship between specific intestinal flora and CKD is still unclear. Materials and Method: To identify genetically predicted microbiota, we used summary data from genome-wide association studies on gut microbiota in 18340 participants from 24 cohorts. Furthermore, we genetically predicted the causal relationship between 211 gut microbiotas and six phenotypes (outcomes) (CKD, estimated glomerular filtration rate (eGFR), urine albumin to creatinine ratio (UACR), dialysis, rapid progress to CKD, and rapid decline of eGFR). Four Mendelian randomization (MR) methods, including inverse variance weighted (IVW), MR-Egger, weighted median, and weighted mode were used to investigate the casual relationship between gut microbiotas and various outcomes. The result of IVW was deemed as the primary result. Then, Cochrane’s Q test, MR-Egger, and MR-PRESSO Global test were used to detect heterogeneity and pleiotropy. The leave-one method was used for testing the stability of MR results and Bonferroni-corrected was used to test the strength of the causal relationship between exposure and outcome. Results: Through the MR analysis of 211 microbiotas and six clinical phenotypes, a total of 36 intestinal microflora were found to be associated with various outcomes. Among them, Class Bacteroidia (=−0.005, 95% CI: −0.001 to −0.008, p = 0.002) has a strong causality with lower eGFR after the Bonferroni-corrected test, whereas phylum Actinobacteria (OR = 1.0009, 95%CI: 1.0003–1.0015, p = 0.0024) has a strong causal relationship with dialysis. The Cochrane’s Q test reveals that there is no significant heterogeneity between various single nucleotide polymorphisms. In addition, no significant level of pleiotropy was found according to MR-Egger and MR-PRESSO Global tests. Conclusions: Through the two-sample MR analysis, we identified the specific intestinal flora that has a causal relationship with the incidence and progression of CKD at the level of gene prediction, which may provide helpful biomarkers for early disease diagnosis and potential therapeutic targets for CKD