Ferromagnetic Property of Co and Ni Doped TiO 2

The Co and Ni doped diluted magnetic semiconductor nanoparticle TiO2 is prepared by sol-gel method. Ti0.97Co0.03O2, Ti0.97Ni0.03O2, Ti0.97Co0.06O2, and Ti0.97Ni0.06O2 samples were characterized by X-ray scattering techniques and high resolution transmission electron microscope. The results show that there are no other phases existing in TiO2. As to the sample of high-concentration dopant, the X-ray scattering techniques have explored the existing of CoTiO3 and NiTiO3. The ferromagnetic measurement shows that the magnetization of the sample of high-concentration dopant increases in the same external magnetic field. However, the relatively higher dopant Co and Ni may form more interstitial ions and paramagnet matters, reducing the oxygen vacancy concentration and finally leading to the decrease of remanent magnetization and coercivity of the materials

The Microstructure of Ni Layer on Single-Walled Carbon Nanotubes Prepared by an Electroless Coating Process

The single-walled carbon nanotubes (SWNTs, diameter: 2~3 nm), which were obtained in the suspension of purification solution, with Ni-P coating layers were obtained by an electroless deposition process. The SWNTs before and after coating were characterized by transmission electron microscopy (TEM) and energy dispersive spectrometry (EDS). An Ni-P layer on individual nanotube with thickness of 20 nm can be obtained after the deposition process. The X-ray diffraction (XRD) and selected area electron diffraction (SAED) analysis of Ni-P SWNTs before and after heat treatment show that the heat treatment caused the transformation of the amorphous Ni-P layer to the nanocrystalline Ni-P (crystalline Ni and Ni3P intermetallic compound) layer. The XRD pattern of SWNTs with Ni-P layers after heat treatment revealed that the crystal structures of Ni in plating layer contained: hexagonal close-packed (hcp) structure and face-centered cubic (fcc) structure. The lattice parameters of Ni (fcc) and Ni3P are larger than the bulk's, indicting that the lattice expansion has taken place. However, the lattice parameter of Ni (hcp) has no difference from the bulk's

Ab initio Investigation of Elasticity and Stability of Metal Aluminum

On the basis of the pseudopotential plane-wave(PP-PW) method in combination with the local-density-functional theory(LDFT), complete stress-strain curves for the uniaxial loading and uniaxial deformation along the [001] and [111] directions, and the biaxial proportional extension along [010] and [001] of aluminium are obtained. During the uniaxial loading, certain general behaviors of energy versus stretch and the load versus the stretch are confirmed; in each acse, there exist three special unstressed structures: f.c.c., b.c.c. and f.c.t. for [001]; f.c.c., s.c. and b.c.c. for [111]. Using stability criteria, we find that all of these state are unstable, and always occur together with shear instability, except the natural f.c.c. structure. A Bain transformation from the stable f.c.c. structure to the stable b.c.c. configuration cannot be obtained by uniaxial compression along any equivalent [001] and [111] direction. The tensile strength are similar for the two directions. For the higher energy barrier of [111] direction, the compressive strength is greater than that for the [001] direction. With increase in the ratio of the biaxial proportional extension, the stress and tensile strength increase; however, the critical strain does not change significantly. Our results add to the existing ab initio database for use in fitting and testing interatomic potentials.Comment: 9 Pages in Revtex and 11 Eps figure

Genomes shed light on the evolution of Begonia, a mega‐diverse genus

Clarifying the evolutionary processes underlying species diversification and adaptation is a key focus of evolutionary biology. Begonia (Begoniaceae) is one of the most species-rich angiosperm genera with ~2,000 species, most of which are shade-adapted. Here, we present chromosome-scale genome assemblies for four species of Begonia (B. loranthoides, B. masoniana, B. darthvaderiana, and B. peltatifolia), and whole genome shot-gun data for an additional 74 Begonia representatives to investigate lineage evolution and shade adaptation of the genus. The four genome assemblies range in size from 331.75 Mb (B. peltatifolia) to 799.83 Mb (B. masoniana), and harbor 22,059 - 23,444 protein-coding genes. Synteny analysis revealed a lineage specific whole-genome duplication (WGD) that occurred just before the diversification of the Begonia. Functional enrichment of gene families retained after WGD highlight the significance of modified carbohydrate metabolism and photosynthesis possibly linked to shade-adaptation in the genus, which is further supported by expansions of gene families involved in light perception and harvesting. Phylogenomic reconstructions and genomics studies indicate that genomic introgression has also played a role in the evolution of Begonia. Overall, this study provides valuable genomic resources for Begonia and suggests potential drivers underlying the diversity and adaptive evolution of this mega-diverse clade

The in vivo metabolic pathway of Deg-AZM and in vitro investigations into the contribution of drug metabolizing enzymes and drug transporters in the drug interactions of Deg-AZM, a clinical-stage new transgelin agonist

IntroductionDeglycosylated azithromycin (Deg-AZM), a new transgelin agonist with positive therapeutic effects on slow transit constipation, has been approved for clinical trials in 2024. This work investigated the drug metabolism and transport of Deg-AZM to provide research data for further development of Deg-AZM.MethodsA combination of UPLC-QTOF-MS was used to obtain metabolite spectra of Deg-AZM in plasma, urine, feces and bile. Caco-2 cells was used to investigate the permeability of Deg-AZM and whether it is a potential substrate of the efflux transporter P-glycoprotein. Human liver microsome phenotyping assays with chemical inhibition and recombinant CYPs phenotyping assays were used to investigate the CYP450 enzyme phenotype involved in Deg-AZM metabolism in vitro. A HLM inhibition reaction system was established to evaluate the inhibitory effect of Deg-AZM on CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4. The mRNA expression of human primary hepatocytes incubated with Deg-AZM or not was evaluate the induction of Deg-AZM on CYP1A2, CYP2B6, and CYP3A4.Results44 metabolites of Deg-AZM were identified in rat urine, feces, bile, and plasma, the metabolic pathways included demethylation, monohydroxylation, dihydroxylation, dehydroxidation, hydroreduction, hydrolysis, methylation, glucuronidation and the combination of different metabolic pathways. Deg-AZM was a low permeability drug in the intestine and a potential substrate of the efflux transporter P-glycoprotein. CYP3A4 was the major CYP isoform responsible for Deg-AZM metabolism. Deg-AZM showed moderate inhibition with CYP2B6 and CYP2D6. Data in three batches of human primary hepatocytes disclosed induction potential of Deg-AZM on CYP2B6 and CYP3A4.ConclusionThe in vivo metabolic pathway of Deg-AZM and in vitro possibility of drug interaction for Deg-AZM with CYP enzymes and drug transporter were fully investigated. It was suggested that dose adjustments may be warranted depending on the potency of the corresponding modulators in clinical

Deglycosylated azithromycin alleviates cisplatin-evoked constipation in mice by altering host metabolome and gut microbiota composition

IntroductionChemotherapy induced constipation (CIC) is a gastrointestinal side effect that occurs in patients receiving chemotherapy, which can further deteriorate the living quality of cancer patients. Deglycosylated azithromycin (Deg-AZM), a newly developed Class I drug with good therapeutic effects on chronic constipation, has been approved for clinical trials in 2024. However, it is unclear whether Deg-AZM has any impact on gut microbiota of CIC mice. The purpose of this study was to explore the role of Deg-AZM in treating CIC by modulating the gut microbiota.MethodsThe therapeutic effects of Deg-AZM on intestinal motility were assessed in a cisplatin-induced CIC mouse model. The gut microbiota composition was analyzed using 16S rRNA sequencing, and metabolic changes were evaluated through untargeted metabolomics of fecal samples.ResultsDeg-AZM significantly enhanced intestinal motility in the mice with cisplatin-evoked constipation. Gut microbiota analysis revealed that Deg-AZM altered the community composition by decreasing Deferribacterota and Pseudomonadota and increasing Bacteroidota, Lactobacillus and Muribaculaceae. The feces metabolomics revealed that alanine, aspartate and glutamate metabolism, citrate cycle (TCA cycle), purine metabolism, primary bile acid biosynthesis and taurine and hypotaurine metabolism in CIC model were modulated by Deg-AZM.ConclusionDeg-AZM could alleviate cisplatin-evoked constipation in mice by reshaping the structure of gut microbial community, which may provide a potential basis for the use and clinical development of Deg-AZM for CIC treatment

Elasticity, Stability and Ideal Strength of β\beta -SiC in plane-wave-based ab initio calculations

On the basis of the pseudopotential plane-wave(PP-PW) method and the local-density-functional theory(LDFT), this paper studies energetics, stress-strain relation, stability and ideal strength of $\beta$-SiC under various loading modes, where uniform uniaxial extension and tension, biaxial proportional extension are considered along directions [001] and [111]. The lattice constant, elastic constants and moduli of equilibrium state are calculated, and the results agree well with the experimental data. As the four Si-C bonds along directions [111], [$\bar{1}$11], [11$\bar{1}$] and [1$\bar{1}$1] are not the same under the loading along [111], internal relaxation and the corresponding internal displacements must be considered. We find that, at the beginning of loading, the effect of internal displacement through shuffle and glide plane diminishes the difference among the four Si-C bonds length, but will increase the difference at the subsequent loading, which will result in a crack nucleated on \{111\} shuffle plane and a subsequently cleavage fracture. Thus the corresponding theoretical strength is 50.8 GPa, which agrees well with the recent experiment value, 53.4 GPa. However, with the loading along [001], internal relaxation is not important for tetragonal symmetry. Elastic constants during the uniaxial tension along [001] are calculated. Based on the stability analysis with stiffness coefficients, we find that the spinodal and Born instabilities are triggered almost at the same strain, which agrees with the previous molecular dynamics simulation. During biaxial proportional extension, stress and strength vary proportionally with the biaxial loading ratio at the same longitudinal strain.Comment: 9 pages, 10 figure