Low-carrier density and fragile magnetism in a Kondo lattice system.

Kondo-based semimetals and semiconductors are of extensive current interest as a viable platform for strongly correlated states in the dilute carrier limit. It is thus important to explore the routes to understand such systems. One established pathway is through the Kondo effect in metallic nonmagnetic analogs, in the so called half-filling case of one conduction electron and one 4f electron per site. Here, we demonstrate that Kondo-based semimetals develop out of conduction electrons with a low-carrier density in the presence of an even number of rare-earth sites. We do so by studying the Kondo material Yb3Ir4Ge13 along with its closed-4f -shell counterpart, Lu3Ir4Ge13. Through magnetotransport, optical conductivity, and thermodynamic measurements, we establish that the correlated semimetallic state of Yb3Ir4Ge13 below its Kondo temperature originates from the Kondo effect of a low-carrier conduction-electron background. In addition, it displays fragile magnetism at very low temperatures, which in turn, can be tuned to a Griffiths-phase-like regime through Lu-for-Yb substitution. These findings are connected with recent theoretical studies in simplified models. Our results can pave the way to exploring strong correlation physics in a semimetallic environment.

Efficacy and safety of rivaroxaban thromboprophylaxis after arthroplasty of the hip or knee: retrospective cohort study.

Introduction Venous thromboembolism (VTE) is a potentially fatal complication of hip arthroplasty and knee arthroplasty. The National Institute for Health and Care Excellence recommend rivaroxaban for VTE prevention. Amid concerns over bleeding complications, the modified thromboprophylaxis policy of Chelsea and Westminster Hospital (CWH; London, UK) advises enoxaparin given after surgery in the inpatient setting followed by rivaroxaban upon hospital discharge. This retrospective study investigated the efficacy and safety of rivaroxaban in this novel, modified venous-prophylaxis regimen in a surgical orthopaedic cohort at CWH. Methods A total of 479 patients who received modified thromboprophylaxis treatment at CWH after hip arthroplasty or knee arthroplasty between April 2013 and October 2014 formed the study cohort. Seven outcomes based on efficacy and safety while undergoing treatment with rivaroxaban were investigated: symptomatic deep-vein thrombosis (DVT), pulmonary embolism (PE), death, stroke, myocardial infarction (MI), major bleeding episodes (MBEs) and non-major bleeding episodes (NMBEs). Median follow-up was 369 days. Fisher's exact and Mann-Whitney U-tests were adopted to identify associations with these outcomes. Results Prevalence of symptomatic PE, DVT, death, stroke and MI during treatment was zero. One (0.2%) MBE and nine (1.9%) NMBEs occurred. The MBE (a wound haematoma) required a return to theatre for aspiration. Off-treatment VTEs occurred in four (0.8%) patients after completion of a course of rivaroxaban, and were associated with known risk factors. Conclusions Rivaroxaban is an effective and safe anticoagulant for thromboprophylaxis after hip arthroplasty or knee arthroplasty if used in a modified regimen involving enoxaparin administered in the inpatient setting followed by rivaroxaban upon hospital discharge.

Normalization, comparison, and scaling of adsorption data: arsenate and goethite.

Various approaches for analyzing adsorption data were examined to determine the best method for reporting and interpreting the results of adsorption experiments and ultimately extrapolating laboratory measurements to the field. The interactions of arsenate and goethite were used as representative adsorbate and adsorbent, respectively, although the general principles are applicable to other adsorbate-adsorbent systems as well. A modeling exercise was conducted first to determine the theoretical principles governing the comparison and scaling of adsorption data. These principles were then tested on a suite of experimental data, both new and previously published. LogK(D) is significantly more sensitive to variations in adsorbate (As(T)) or adsorbent (Fe(T)) concentrations than either adsorbed concentration (q) or percentage adsorbed. The sensitivity of K(D) relative to q occurs due to the non-linearity of the adsorption isotherm at a given pH, since as the equilibrium aqueous concentration approaches zero, q also approaches zero while K(D) approaches infinity. Varying As(T) and Fe(T) while keeping As(T)/Fe(T) fixed yields more consistent values of percentage adsorbed, logK(D), and q, although the adsorbate-to-adsorbent ratios used in laboratory studies often have a rather narrow range compared to those possible in the field. Specific surface area is also a better scaling parameter than the mass of adsorbent, especially between systems with differing adsorbents with markedly different specific surface areas (e.g., natural versus synthetic goethite). Our results have significant implications to contaminant transport modeling, as the constant K(D) approach is the most common method of modeling contaminant transport, while contaminant concentrations in the field are typically low, precisely the conditions where K(D) is most sensitive.

Antibacterial activity of root extract of trianthema decandra.

Methanolic extract of Trianthema decandra was investigated for its antibacterial activity against staphylococcus aureus (NCIM 2079), Escherichia coli (NCIM 2065), Bacillus subtilis (NCIM 2063), Pseudomonas aeruginosa (NICIM 2036) and Proteus vulgaris (NICIM 2027) at 100 µg/disc using disc diffusion method. The extract showed significant antibacterial activity and were comparable to Chloramphenicol (30/ µg/disc). Our findings confirm the traditional therapeutic claims for this herb.

Color stability of a resin-modified glass ionomer cement.

The color stability of a resin-modified glass ionomer cement (Fuji II LC) was investigated over six months using colorimetry. Five shades (A2, A3, A4, B3 and C4) were selected and 10 square specimens (7 mm wide and long, and 1.5 mm deep) were made for each shade using special grit molds. CIE L*, a*, b* color parameters of the specimens were taken at one day, one week, one month, three months and six months. Results were subjected to MANOVA and ANOVA/Scheffe's test at significance level 0.05. The effects of time on color parameters (L*, a*, b* values) were found to be shade dependent. All shades exhibited a decrease in L* values over time. With the exception of shade B3, significant differences in L* values were observed at six months. A general decrease in b* values was also observed but differences among the various time intervals were not significant except for shades A3 and C4. No apparent trends were observed for changes in a* values. For all shades, the largest color change (delta E) was observed between one day and one week. The color stability of the resin-modified glass ionomer investigated was shade dependent. A general decrease in lightness and yellow chroma was observed.

Polymerization color changes of esthetic restoratives.

The color changes of three different types of tooth-colored restoratives during polymerization were investigated using colorimetry. L*, a*, b* color parameters of five different shades of Z100 (a mini-filled composite resin), Fuji II LC (a resin-modified glass-ionomer cement), and Dyract (a polyacid-modified composite resin) were taken precure and postcure. The results showed that the restoratives evaluated all underwent color changes during polymerization. The polymerization changes in color parameters were shade and not material dependent. Changes in L* parameter or lightness during polymerization were significant for all material and shade combinations and had the greatest influence on the overall polymerization color change. As the color change was perceivable by the human eye for most shades of materials, the clinical practice of polymerizing some material on, or adjacent to, the undried tooth to confirm shades of esthetic restoratives before restorative procedures is prudent.

Anti inflammatory activity of moringa oliefera. Lam.

The aqueous and ethanolic (90%) extract of the leaves of M.Oliera Lam (Fam: Moringaceae) were studied for their anti inflammatory action in ale albino rats. Two extracts exhibited maximum action within two hours of challenge. The aqueous extract sowed significant (P<0.01) odema suppression similar to that of Ibuprofen at the first hour of carrageenan injection. The results confirms the folkers claim of the plant.