Fe73.5Si13.5B9Cu1Nb3 metallic glass: Rapid activation of peroxymonosulfate towards ultrafast Eosin Y degradation

Discovering functional applications of metallic glasses (MGs) as heterogeneous catalysts is a fundamental and essential topic. This work reports the rapid production of sulfate radicals (SO4−) from peroxymonosulfate (PMS) using Fe73.5Si13.5B9Cu1Nb3 glassy ribbons as catalysts for Eosin Y (EY) dye wastewater treatment. The reaction rates (k) from the experimental data reveal that the EY degradation is well fitted with the pseudo-first-order kinetic model. The strong electron transfer ability is characterized by electrochemical methods, presenting an advanced catalytic performance for EY degradation. Various experimental parameters, including dye concentration, catalyst dosage, PMS concentration, light intensity, pH and reaction temperature as well as the saline and natural inorganic effects, are fully investigated. The results show that the color removal of EY dye could achieve nearly 100% within 20 min. The quenching experiments are performed to verify the production of reactive species, suggesting that both OH and SO4− are produced from PMS and play significant roles in EY degradation. This critical study reveals that using Fe73.5Si13.5B9Cu1Nb3 MGs as catalysts exhibits a superior reactivity on PMS activation in wastewater treatment. The discoveries shed lights into the study of electron transfer ability for MGs, presenting extensive prospects in the application of dye wastewater treatment

Composite quantitative knee structure metrics predict the development of accelerated knee osteoarthritis:data from the osteoarthritis initiative

BACKGROUND: We aimed to determine if composite structural measures of knee osteoarthritis (KOA) progression on magnetic resonance (MR) imaging can predict the radiographic onset of accelerated knee osteoarthritis. METHODS: We used data from a nested case-control study among participants from the Osteoarthritis Initiative without radiographic KOA at baseline. Participants were separated into three groups based on radiographic disease progression over 4 years: 1) accelerated (Kellgren-Lawrence grades [KL] 0/1 to 3/4), 2) typical (increase in KL, excluding accelerated osteoarthritis), or 3) no KOA (no change in KL). We assessed tibiofemoral cartilage damage (four regions: medial/lateral tibia/femur), bone marrow lesion (BML) volume (four regions: medial/lateral tibia/femur), and whole knee effusion-synovitis volume on 3 T MR images with semi-automated programs. We calculated two MR-based composite scores. Cumulative damage was the sum of standardized cartilage damage. Disease activity was the sum of standardized volumes of effusion-synovitis and BMLs. We focused on annual images from 2 years before to 2 years after radiographic onset (or a matched time for those without knee osteoarthritis). To determine between group differences in the composite metrics at all time points, we used generalized linear mixed models with group (3 levels) and time (up to 5 levels). For our prognostic analysis, we used multinomial logistic regression models to determine if one-year worsening in each composite metric change associated with future accelerated knee osteoarthritis (odds ratios [OR] based on units of 1 standard deviation of change). RESULTS: Prior to disease onset, the accelerated KOA group had greater average disease activity compared to the typical and no KOA groups and this persisted up to 2 years after disease onset. During a pre-radiographic disease period, the odds of developing accelerated KOA were greater in people with worsening disease activity [versus typical KOA OR (95% confidence interval [CI]): 1.58 (1.08 to 2.33); versus no KOA: 2.39 (1.55 to 3.71)] or cumulative damage [versus typical KOA: 1.69 (1.14 to 2.51); versus no KOA: 2.11 (1.41 to 3.16)]. CONCLUSIONS: MR-based disease activity and cumulative damage metrics may be prognostic markers to help identify people at risk for accelerated onset and progression of knee osteoarthritis

Early pre-radiographic structural pathology precedes the onset of accelerated knee osteoarthritis.

BACKGROUND: Accelerated knee osteoarthritis (AKOA) is characterized by more pain, impaired physical function, and greater likelihood to receive a joint replacement compared to individuals who develop the typical gradual onset of disease. Prognostic tools are needed to determine which structural pathologies precede the development of AKOA compared to individuals without AKOA. Therefore, the purpose of this manuscript was to determine which pre-radiographic structural features precede the development of AKOA. METHODS: The sample comprised participants in the Osteoarthritis Initiative (OAI) who had at least one radiographically normal knee at baseline (Kellgren-Lawrence [KL] grade  3) and No AKOA. The index visit was the study visit when participants met criteria for AKOA or a matched timepoint for those who did not develop AKOA. Magnetic resonance (MR) images were assessed for 12 structural features at the OAI baseline, and 1 and 2 years prior to the index visit. Separate logistic regression models (i.e. OAI baseline, 1 and 2 years prior) were used to determine which pre-radiographic structural features were more likely to antedate the development of AKOA compared to individuals not developing AKOA. RESULTS: At the OAI baseline visit, degenerative cruciate ligaments (Odds Ratio [OR] = 2.2, 95% Confidence Interval [CI] = 1.3,3.5), infrapatellar fat pad signal intensity alteration (OR = 2.0, 95%CI = 1.2,3.2), medial/lateral meniscal pathology (OR = 2.1/2.4, 95%CI = 1.3,3.4/1.5,3.8), and greater quantitative knee effusion-synovitis (OR = 2.2, 95%CI = 1.4,3.4) were more likely to antedate the development of AKOA when compared to those that did not develop AKOA. These results were similar at one and two years prior to disease onset. Additionally, medial meniscus extrusion at one year prior to disease onset (OR = 3.5, 95%CI = 2.1,6.0) increased the likelihood of developing AKOA. CONCLUSIONS: Early ligamentous degeneration, effusion/synovitis, and meniscal pathology precede the onset of AKOA and may be prognostic biomarkers

In Vitro and Sensory Evaluation of Capsaicin-Loaded Nanoformulations

Capsaicin has known health beneficial and therapeutic properties. It is also able to enhance the permeability of drugs across epithelial tissues. Unfortunately, due to its pungency the oral administration of capsaicin is limited. To this end, we assessed the effect of nanoencapsulation of capsaicin, under the hypothesis that this would reduce its pungency. Core-shell nanocapsules with an oily core and stabilized with phospholipids were used. This system was used with or without chitosan coating. In this work, we investigated the in vitro release behavior of capsaicin-loaded formulations in different physiological media (including simulated saliva fluid). We also evaluated the influence of encapsulation of capsaicin on the cell viability of buccal cells (TR146). To study the changes in pungency after encapsulation we carried out a sensory analysis with a trained panel of 24 students. The in vitro release study showed that the systems discharged capsaicin slowly in a monotonic manner and that the chitosan coating had an effect on the release profile. The cytotoxic response of TR146 cells to capsaicin at a concentration of 500 μM, which was evident for the free compound, was reduced following its encapsulation. The sensory study revealed that a chitosan coating results in a lower threshold of perception of the formulation. The nanoencapsulation of capsaicin resulted in attenuation of the sensation of pungency significantly. However, the presence of a chitosan shell around the nanoformulations did not mask the pungency, when compared with uncoated systems

Microscopic origin of highly enhanced supercurrent in 122 pnictide superconductor

By a combination of microstructure analysis techniques, we reveal the structural origin of the extremely high supercurrent (up to the practical level of 0.1 MA/cm 2 at 10 T, 4.2 K) in Sr 0.6 K 0.4 Fe 2 As 2 (122) tape. Transmission Kikuchi diffraction analysis reveals that hot pressing promotes a very high fraction of low-angle grain boundaries and texturing of the crystals, which is beneficial for the intergrain physical properties. Moreover, the unique characteristics of low-angle grain boundaries favor both long-range dislocations and short-range dislocations that totally change the pinning mechanism of the bulk 122 system. These defects combined with the grain texturing are not only effective for pinning vortices in the superconducting state, but also improve inter-granular supercurrent degradation, leading to substantially enhanced supercurrent over a wide range of magnetic fields

Structure and Diffusion of ZnO-SrO-CaO-Na2O-SiO2 Bioactive Glasses: A Combined High Energy X-Ray Diffraction and Molecular Dynamics Simulations Study

Novel bioactive glasses that can release ions such as strontium and zinc provide bone growth enhancement and antibacterial properties that earlier-generation bio glasses did not possess. These glasses find applications in bone cementation, restoration and in tissue engineering. In this paper, we present combined experimental and simulation studies to explain the structure and diffusion of ZnO-SrO-CaO-Na2O-SiO2 bioactive glasses with the aim of understanding the short and medium range structure of these glasses, the structural correlation to their dissolution behaviors, and their bioactivity. High energy X-ray diffraction experiments have been performed to obtain structural information and to validate the structure models from simulations. Three glass compositions with ZnO/Na2O substitutions have been studied using molecular dynamics simulations to characterize the glass structure and calculate the ionic diffusion in these glasses. The results provide insight to local environments and structural role of zinc ions, the medium range structural features such as Qn distribution, and ionic diffusion characteristics of these bioactive glasses. The structure and ionic diffusion results are discussed in correlation to the dissolution behaviors and the bioactivity of these glasses. © 2013 The Royal Society of Chemistry