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Bioactive glass nanoparticles (BGNs) are well-recognized multifunctional biomaterials for bone tissue regeneration due to their capability to stimulate various cellular processes through released biologically active ions. Understanding the correlation between BGN composition and cellular responses is key to developing clinically usable BGN-based medical devices. This study investigated the influence of CaO content of binary SiO 2 -CaO BGNs (CaO ranging from 0 to 10 mol%) on osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) and in vivo bone regeneration in zebrafish osteoporosis model. The results showed that BGNs could promote osteogenic differentiation of rBMSCs by indirectly releasing active ions or directly interacting with rBMSCs by internalization. In both situations, BGNs of a higher CaO content could promote the osteogenic differentiation of rBMSCs to a greater extent. The internalized BGNs could activate the transcription factors RUNX2 and OSX, leading to the expression of osteogenesis-related genes. The results in the zebrafish osteoporosis model indicated that the presence of BGNs of higher CaO contents could enhance bone regeneration and rescue dexamethasone-induced osteoporosis to a greater extent. These findings demonstrate that BGNs can stimulate osteogenic differentiation of rBMSCs by releasing active ions or internalization. A higher CaO content facilitates osteogenesis and bone regeneration of zebrafish as well as relieving dexamethasone-induced osteoporosis. The zebrafish osteoporosis model can be a potent tool for evaluating the in vivo bone regeneration effects of bioactive materials. Bioactive glass nanoparticles (BGNs) are increasingly used as fillers of nanocomposites or as delivery platforms of active ions to regenerate bone tissue. Various studies have shown that BGNs can enhance osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) by releasing active ions. However, the correlation between BGN composition and cellular responses and in vivo bone regeneration effect has still not been well investigated. Establishment of a suitable in vivo animal model for investigating this correlation is also challenging. The present study reports the influence of CaO content in binary SiO 2 -CaO BGNs on osteogenic differentiation of BMSCs extracellularly and intracellularly. This study also demonstrates the suitability of zebrafish osteoporosis model to investigate in vivo bone regeneration effect of BGNs. [Display omitted] [ABSTRACT FROM AUTHOR]

The operational stability of chloroperoxidase (CPO) was considerably enhanced by coupling with glucose oxidase (GOx) because H 2 O 2 could be generated in situ from glucose and oxygen. In this paper, a CPO–GOx nanoreactor was fabricated on the surface of Au@Fe 3 O 4 nanoparticles through layer-by-layer assembly using the specific avidin–biotin interaction. The X-ray diffraction data indicated the presence of both Fe and Au in the Au@Fe 3 O 4 carrier. The Au@Fe 3 O 4 displayed a uniform core/shell nanostructure, whereas the nanoparticles of the bienzymatic reactor were larger than the carrier. The catalytic activity of CPO was highly dependent on the structure of the enzymatic nanoreactor. The activity of Au@Fe 3 O 4 –GOx (inner)–CPO (outer) was 15.5% higher than that of Au@Fe 3 O 4 –CPO (inner)–GOx (outer). Moreover, Au@Fe 3 O 4 –GOx–CPO exhibited better thermostability. Au@Fe 3 O 4 –GOx–CPO retained 53.2% of its initial activity after incubation for 1.0 h at 60 °C and 30.4% of its initial activity after 18 h at 50 °C. Au@Fe 3 O 4 –GOx–CPO had good reusability. It retained more than 62.4% of its activity after the 12th cycle. This was attributed to the cage-like structure in Au@Fe 3 O 4 –GOx–CPO, which could effectively prevent the removal of the enzyme molecules from the carrier. [ABSTRACT FROM AUTHOR]

CoTiO 3 nanocrystallites with an average diameter of 40 nm were prepared by the sol–gel method using C 10 H 16 N 2 O 8 (EDTA) as the chelating agent. The thermal decomposition process and chemical bonding of the precursor were studied by thermogravimetric-differential scanning calorimetry and fourier transform infrared spectra, respectively. The as-prepared nanocrystallites were characterized by X-ray diffraction, field-emission scanning electron microscopy and transmission electron microscopy. The effects of calcination temperature, sol pH and chelating agent on the formation of CoTiO 3 were investigated. The results show that calcination temperature is a key factor controlling the composition of the products. Acid sol is the optimum condition for hydrolysis and polycondensation of Ti(OC 4 H 9 ) 4 . Co 2+ and Ti 4+ were bonded together by EDTA, and pure CoTiO 3 nanocrystallites were obtained due to this chelating effect. The chelating mechanism and the formation process of CoTiO 3 in the sol–gel process were proposed. Furthermore, the nano-CoTiO 3 was applied to make a gas sensor, and the response value to 104 ppm ethanol was 17.9, response time and the recovery time were 13 s and 10 s, respectively. [ABSTRACT FROM AUTHOR]

Abstract: In order to evaluate the cesium-induced toxic functional changes in organisms, transmembrane activities of cesium 5-sulfosalicylate (Cs(H2Ssal)) into human erythrocyte in vitro is presented in this paper, including kinetic characteristic of transport process and pathways involved in it. The uptake amount of Cs(H2Ssal) by erythrocyte was determined both by Graphite Furnace Atomic Absorption Spectrometry (GFAAS) and spectrofluorimetry. The pathways of Cs(H2Ssal) transporting into erythrocyte are proposed according to inhibition investigation. The influence of Cs(H2Ssal) on morphological properties of erythrocytes was examined using Scanning Electron Microscopy (SEM) to determined the endurable concentration extent of erythrocytes to Cs(H2Ssal). Results show that transmembrane of Cs(H2Ssal) has characteristic of first-order kinetic process during the first 2h, and four pathways were involved in its transporting activities: Ca2+ channel, Na+-K+ pump, Na+-Cs+ countertransport, and anion Cl−/CsCO3 − exchange. The transmembrane process of Cs(H2Ssal) can both prevent the uptake of K+ and induces abnormal accumulation of extracellular K+ as well as occupy some K+-binding sites in protein, causing some tissues losing their activities and functions. Only high concentrations of Cs(H2Ssal) could change morphological properties of erythrocytes greatly and cause hemolysis eventually. [Copyright &y& Elsevier]

Abstract: The Gibbs energy interaction parameters of RbCl with some monosaccharides (d-glucose, d-galactose, d-xylose, and d-arabinose) in water, g ES, were obtained from electromotive force (emf) measurements of the electrochemical cell without liquid junction and containing two ion-selective electrodes (ISE): K-ISE∣RbCl(m E)∣ISE-Cl and K-ISE∣RbCl(m E),saccharide (m S)∣ISE-Cl, at 298.15K. The enthalpy interaction parameters of RbCl with these monosaccharides in water, h ES, are determined according to the McMillan–Mayer theory from the measurements of the enthalpies of mixing of aqueous RbCl solutions with aqueous monosaccharide solutions, as well as the enthalpies of dilution of RbCl and monosaccharide solutions in pure water at 298.15K by a calorimetric method. Furthermore, the entropy interaction parameters, sES, can be evaluated through g ES and h ES. The results suggest that the electrostatic interactions of these monosaccharides with RbCl in water are predominant compared with structural interactions, and these parameters are controlled primarily by the stereochemical structure of the monosaccharides in water. [Copyright &y& Elsevier]

The objective of this paper is to investigate the role of different types of users in the diffusion of situational information through online social networks in disasters. In particular, this paper investigates the influence of two types of users: crowd (regular users) and hubs (users with a large number of followers) on the speed and magnitude of information propagation. Effective and efficient disaster response requires rapid dissemination of situational information to improve situation awareness, save lives, and quickly repair damages. The use of social media, such as Twitter, has gained popularity for spreading the situational information in disasters. Little is known, however, regarding the underlying diffusion mechanisms influencing the speed and magnitude of spreading disaster-related information on social media. To address this gap, using tweets related to Hurricane Harvey, this study examined the role of hubs and crowd and the influence of different features such as theme, hashtag, media, users' location, and the intervention timing of online users on the speed and magnitude of information spread. The results compare the differences in the speed and magnitude of information spread between two diffusion patterns: crowd diffusion (less than 2% retweets from hubs) and mixed diffusion (more than 2% retweets from hubs). The findings suggest that both diffusion patterns can achieve high speed and high magnitude in terms of information diffusion for trending tweets with different features. For mixed diffusion, the speed and magnitude of the tweets are governed by the activities of hubs. The results also show that early intervention of hubs increases the speed of information propagation. Also, in the crowd diffusion, information spread is influenced by both crowd and hubs whose retweets cause tipping points in the information diffusion process at different points of time. The findings imply intervention strategies to better disseminate situational information in disasters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient bio-nanoreactor constructed by modified core–shell magnetic dendritic silica (MDSP). • Phase-transitioned lysozyme (PTL) covered around MDSP plays multiple roles. • The matching of channel in MDSP with CPO size avoid aggregation of CPO. • Magnetic separation instead of centrifugation greatly decrease the loss of the material in reuse. • The bio-nanoreactor is very effective in degradation of antibiotic residues (nofloxacin). Immobilization of enzyme on porous solid nanosupport is an effective way to improve its stability. In this work, core–shell magnetic dendritic silica nanoparticle (MDSP) is prepared for encapsulation of chloroperoxidase (CPO). Amyloid like proteins formed by phase-transitioned lysozyme(PTL) is covered around CPO@MDSP to hold another layer of CPO (CPO@PTL-CPO@MDSP). CPO@PTL-CPO@MDSP is very stable at high temperature and in the presence of organic solvent. 91.3 % of catalytic activity at 80 °C is remained compared to 37.5 % of free enzyme. 78.2 % of original activity are retained in the presence of 30 % methanol, while the free enzyme can only keep 13.5 % of activity. CPO@PTL-CPO@MDSP can remain 77.0 % of the original catalytic activity remained after 24 cycles. In the application on the degradation of norfloxacin, 95.2 % of degradation efficiency is achieved in 20 min. This work provides a universal platform for the design of enzyme nanoreactor suitable for industrial application. [ABSTRACT FROM AUTHOR]

Epitaxial thin films of La 0.9 Ca 0.1 MnO 3 were grown on (100) oriented 0.7Pb(Mg 1/3 Nb 2/3 )O 3 -0.3PbTiO 3 (PMN-PT) single-crystal substrates by pulsed laser deposition. The heterostructure composed of manganite and ferroelectric would enable us to control and study the electric/magnetic properties of manganite by means of tunable strain induced via the piezoelectric effect of PMN-PT. X-ray diffraction revealed that the ferroelectric poling remarkably modify the in-plane tensile strain introduced in the La 0.9 Ca 0.1 MnO 3 film, which gives rise to tune resistance and Curie temperature T C . It is also found that due to poling of PMN-PT the magnetoresistance of La 0.9 Ca 0.1 MnO 3 is reduced in the paramagnetic state, but increased in ferromagnetic state. The observed effects of residual strain on magnetoresistance could be explained by the Jahn-Teller distortion and polarization effect on the coexistence of multiple phases. [ABSTRACT FROM AUTHOR]

Earth-abundant and ecofriendly minerals SnS x Se 2–x can be promising candidates for photoelectrochemical (PEC) cells because of their tunable band gaps and high absorption efficiency in the visible light range. In this paper, p type SnS thin films with sheet-like morphologies were successfully prepared by CBD method and then n-type SnS x Se 2-x thin films were achieved by selenization annealing of SnS thin films. The physical properties and PEC performances of SnS x Se 2-x thin films influenced by the annealing process were detailed studied. The photocurrent densities and stability of SnS x Se 2-x films were further improved by the deposition of p-type CdS:Cu buffer layer. And the fabrication of FTO/SnS x Se 2-x /CdS:Cu/TiO 2 /Pt photocathode improved the PEC performance further and the photocurrent as high as 10.5 mA/cm2 had been achieved. IPCE tests indicated that the FTO/SnS x Se 2-x /CdS:Cu/TiO 2 /Pt structure achieved a power conversion efficiency of 31.3 %. •SnS thin films were deposited by CBD method, and SnS x Se 2-x thin films were prepared by selenization annealing. •The effects of different selenization temperatures and different amounts of selenium powder on SnS x Se 2-x films were studied. •By introducing CdS: Cu buffer layer with different deposition times, TiO 2 protective layer with varying thickness, and precious metal Pt for surface modification, the photoelectric performance of SnS x Se 2-x thin films was optimized. [ABSTRACT FROM AUTHOR]

Abstract: The decolorization/degradation of aqueous azo dyes generated by textile photography industries are a main issue in wastewater treatment. Despite many significant efforts and numerous systems have been exploited, the problem is still unsolved due to intrinsically low activity or use of non-convenient chemical reagents. Biodegradation appears to be one of the most efficient ways, however, the initial step of biotransformation usually involves a reductive cleavage of the azo bond, which under anaerobic conditions leads to the formation of aromatic amines known to be carcinogenic. This study shows that applying an oxidative process of H2O2 catalyzed by chloroperoxidase (CPO) for decolorization/degradation of aqueous azo dyes (Orange G and Sunset Yellow) in buffer solution is a very efficient system. The effect of initial pH, dosage of enzyme, H2O2 concentration, reaction temperature and time, and suitable initial dye concentration on the decolorization efficiency were investigated in detail and optimized accordingly. At optimum reaction condition, the decolorization efficiency of Orange G reached 98.72% in 5min, and 77.25% in 10min for Sunset Yellow. The dosage of CPO was below ppm level. This enzymatic reaction is an ideal potential alternative for application on decolorization/degradation of aqueous azo dyes. Furthermore, the elucidation of degradation pathways is of special interest considering healthy and environmental priorities. In this work, LC–MS was used to determine the structures of intermediates arising from Orange G by CPO–H2O2 oxidation. Eight transformation products were identified and two types of cleavage were proposed for the degradation pathway. [Copyright &y& Elsevier]