High field magnetic resonant properties of beta'-(ET)2SF5CF2SO3

A systematic electron spin resonance (ESR) investigation of the low temperature regime for the (ET)2SF5CF2SO3 system was performed in the frequency range of ~200-700 GHz, using backward wave oscillator sources, and at fields up to 25 T. Newly acquired access to the high frequency and fields shows experimental ESR results in agreement with the nuclear magnetic resonance (NMR) investigation, revealing evidence that the transition seen at 20 K is not of conventional spin-Peierls order. A significant change of the spin resonance spectrum in beta'-(ET)2SF5CF2SO3 at low temperatures, indicates a transition into a three-dimensional-antiferromagnetic (3D AFM) phase.Comment: 4 pages, 7 figures, minor grammatical change

Charge Ordering in alpha-(BEDT-TTF)2I3 by synchrotron x-ray diffraction

The spatial charge arrangement of a typical quasi-two-dimensional organic conductor alpha-(BEDT-TTF)2I3 is revealed by single crystal structure analysis using synchrotron radiation. The results show that the horizontal stripe type structure, which was suggested by mean field theory, is established. We also find the charge disproportion above the metal-insulator transition temperature and a significant change in transfer integrals caused by the phase transition. Our result elucidates the insulating phase of this material as a 2k_F charge density localization.Comment: 8 pages, 5 figures, 1 tabl

N-Methylimidazole Promotes The Reaction Of Homophthalic Anhydride With Imines

The addition of N-methylimidazole (NMI) to the reaction of homophthalic anhydride with imines such as pyridine-3-carboxaldehyde-N-trifluoroethylimine (9) reduces the amount of elimination byproduct and improves the yield of the formal cycloadduct, tetrahydroisoquinolonic carboxylate 10. Carboxanilides of such compounds are of interest as potential antimalarial agents. A mechanism that rationalizes the role of NMI is proposed, and a gram-scale procedure for the synthesis and resolution of 10 is also described

Variations in strain affect friction and microstructure evolution in copper under a reciprocating tribological load

The microstructure of the materials constituting a metallic frictional contact strongly influences tribological performance. Being able to tailor friction and wear is challenging due to the complex microstructure evolution associated with tribological loading. Here, we investigate the effect of the strain distribution on these processes. High-purity copper plates were morphologically surface textured with two parallel rectangles—referred to as membranes—over the entire sample length by micro-milling. By keeping the width of these membranes constant and only varying their height, reciprocating tribological loading against sapphire discs resulted in different elastic and plastic strains. Finite element simulations were carried out to evaluate the strain distribution in the membranes. It was found that the maximum elastic strain increases with decreasing membrane stiffness. The coefficient of friction decreases with increasing membrane aspect ratio. By analyzing the microstructure and local crystallographic orientation, we found that both show less change with decreasing membrane stiffness

Modulation of the microbiota-gut-brain axis by probiotics in a murine model of inflammatory bowel disease.

UnlabelledAnxiety, depression, and altered memory are associated with intestinal diseases, including inflammatory bowel disease (IBD). Understanding the link between these behavioral changes and IBD is important clinically since concomitant mood disorders often increase a patient's risk of requiring surgery and developing secondary functional gastrointestinal diseases. Anxiety-like behavior (light/dark box test) and recognition memory (novel object recognition task) were determined at the peak and during resolution of inflammation in the dextran sodium sulfate (DSS) mouse model of acute colitis. DSS (5 days) was administered via drinking water followed by 3 or 9 days of normal drinking water to assess behavior during active or resolving inflammation, respectively. Disease (weight, colon length, and histology) was assessed and the composition of the gut microbiota was characterized by using qPCR on fecal pellet DNA. In a subset of mice, pretreatment with probiotics was started 1 wk prior to commencing DSS. During active inflammation (8 days), mice demonstrated impaired recognition memory and exhibited anxiety-like behavior vs.ControlsThese behavioral defects were normalized by 14 days post-DSS. Shifts in the composition of the gut microbiota were evident during active inflammation, notably as decreases in lactobacilli and segmented filamentous bacteria, which were also reversed once the disease had resolved. Administration of probiotics could prevent the behavioral defects seen in acute DSS. Taken together, our findings indicate that changes in mood and behavior are present during acute inflammation in murine IBD and associated with dysbiosis and that these outcomes can be prevented by the administration of probiotics

Modulation of the microbiota-gut-brain axis by probiotics in a murine model of inflammatory bowel disease.

UnlabelledAnxiety, depression, and altered memory are associated with intestinal diseases, including inflammatory bowel disease (IBD). Understanding the link between these behavioral changes and IBD is important clinically since concomitant mood disorders often increase a patient's risk of requiring surgery and developing secondary functional gastrointestinal diseases. Anxiety-like behavior (light/dark box test) and recognition memory (novel object recognition task) were determined at the peak and during resolution of inflammation in the dextran sodium sulfate (DSS) mouse model of acute colitis. DSS (5 days) was administered via drinking water followed by 3 or 9 days of normal drinking water to assess behavior during active or resolving inflammation, respectively. Disease (weight, colon length, and histology) was assessed and the composition of the gut microbiota was characterized by using qPCR on fecal pellet DNA. In a subset of mice, pretreatment with probiotics was started 1 wk prior to commencing DSS. During active inflammation (8 days), mice demonstrated impaired recognition memory and exhibited anxiety-like behavior vs.ControlsThese behavioral defects were normalized by 14 days post-DSS. Shifts in the composition of the gut microbiota were evident during active inflammation, notably as decreases in lactobacilli and segmented filamentous bacteria, which were also reversed once the disease had resolved. Administration of probiotics could prevent the behavioral defects seen in acute DSS. Taken together, our findings indicate that changes in mood and behavior are present during acute inflammation in murine IBD and associated with dysbiosis and that these outcomes can be prevented by the administration of probiotics