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To better understand the focusing process and to determine the focusing position ( z foc ) in Asymmetrical Flow Field-Flow Fractionation (AF4), theoretical and experimental studies were performed. A new theoretical expression that allows the calculation of z foc in AF4 channels of any shape having an axial plane of symmetry was established. The equation was then applied to the particular case of a trapezoidal AF4 channel with tapered ends. The applicability of this equation was verified by comparing the calculated results with the experimental measures of the focusing position obtained using blue dextran dye under different flow conditions. The calculated values and the experimental results were in good agreement. The total uncertainty associated with the calculated z foc was evaluated and was lower than 10%. A good repeatability and reproducibility of the focusing position was obtained. Moreover, the effects of the sample-injection position, the spacer thickness, the membrane aging, and the nature of the injected sample on the focusing position were investigated: z foc was not influenced by these parameters, proving the universal applicability of the equation given in this work for predicting the focusing position, when the assumption of constancy of the cross-flow velocity at the membrane, which underlies this equation, is fulfilled. Additionally, it is notable that this theoretical expression is suitable for different models of AF4 channel and not peculiar to specific suppliers. [ABSTRACT FROM AUTHOR]

Surface engineering is crucial in the colloidal stability and biocompatibility of nanoparticles (NPs). Protein silk fibroin (SF), which gained interest in biomaterial and regenerative medicine, was used in this study to stabilize gold (Au) NPs. Characterization results from UV–Vis spectroscopy revealed that SF-capped Au NPs (SF-Au NPs) possessed remarkable colloidal stabilities in the pH range of 2 to 11 and salt concentration range of 50 mM to 1000 mM. In addition, dried particle samples were resuspended after lyophilization without aggregation. The results indicated that the steric hindrance rather than the electrostatic repulsion of SF-Au NPs was essential for colloidal stability. The SF-Au NPs manifested improved cytocompatibility compared with bare Au NPs, which was attributed to the inherent non-cytotoxicity of SF and the good colloidal stability of the NPs. The proposed method was simpler, more efficient, and more cost effective than the conventional modification strategies for Au NPs; thus, SF-Au NPs can be potentially used in biomedical applications. [ABSTRACT FROM AUTHOR]

• Dynamic transition theory is used on couple-stress fluid saturated porous media convection problem. • Complete description of the global dynamics on and during the onset of convection is obtained. • Approximate bifurcated solutions are given and corresponding roll structures are visualized. • Transition types are determined during the onset of convection. In this article, we study the stability and transition of couple stress fluid saturated porous media, heated from below and cooled from above by employing a thermal non-equilibrium model. Careful analysis shows that the thermal non-equilibrium model has a global attractor, and the global attractor only consists of the basic solution if the Rayleigh number is equal or below a threshold. In generic case where the transitioning eigenvalue has multiplicity one, we show that the transition involved is of continuous type, and the basic solution will be bifurcated to two stable convection solutions which attract globally. If the leading eigenvalue multiplicity is two, the transition is also continuous and a global attractor homeomorphic to the unit circle bifurcates. The attractor then contains four steady-state convection solutions, two of which are stable while the other two are unstable. Further numerical works give more details in the transition process including the bifurcated roll structure. [ABSTRACT FROM AUTHOR]

Surface waters from three catchments having contrasting land-uses (forested, agricultural, and urban) were sampled monthly and analysed for nanoparticulate titanium dioxide (NPs-TiO 2) by single particle ICPMS and electron microscopy. We report one-year of data for NPs-TiO 2 having average number and mass concentrations of 9.1 × 108 NPs-TiO 2 particles L-1 and 11 µg NPs-TiO 2 L-1 respectively. An increase in concentration during warmer months is observed in the forested and agricultural catchments. Both concentrations of NPs-TiO 2 are within the range of recently reported values using similar analytical approaches. The positive correlations for NPs-TiO 2 mass concentration or particle number with the concentration of some trace elements and DOC in the forested and agricultural catchments suggest the detected NPs-TiO 2 in these two systems are mostly from geogenic origin. Additionally, microscopy imaging confirmed the presence of NPs in the three catchments. Furthermore, the land-area normalized annual flux of NPs-TiO 2 (1.65 kg TiO 2 year-1 km-2) was highest for the agricultural catchment, suggesting that agricultural practices have a different impact on the NPs-TiO 2 dynamics and exports than other land-uses (urban or forestry). A similar trend is also found by the reanalysis of recent literature data. [Display omitted] • The land-use has an impact on the TiO 2 nanoparticle concentrations, biogeochemistry, dynamics and exports rates. • Higher amounts of small sized TiO 2 nanoparticles are detected by sp-ICPMS. • Ti speciation varies with the type of soils and land-use. • DOM controls the number of TiO 2 nanoparticles in surface water samples. • Land-use impacts TiO 2 nanoparticles concentrations, dynamics and exports rates. [ABSTRACT FROM AUTHOR]

Abstract: A novel fiber-optic sensor structure fabricated by cascading two optical microfiber knot resonators (MKRs) is proposed and demonstrated in this paper. A theoretical model for describing the principle of the sensing structure is given and its temperature responses are characterized experimentally. Experimental results show that high-precision and simultaneous multi-point temperature sensing in micro-scale can be achieved. Such a sensing structure also has the potential for achieving dual-parameter measurement to eliminate the cross-talk between two parameters in micro-scale. [Copyright &y& Elsevier]

Abstract: Biomimetic acryloyloxyethyl phosphorylcholine (APC) was used to react with generation 5 poly(amido amine) (PAMAM) dendrimers (G5) via the Michael addition reaction between primary amino group of PAMAM dendrimers and acrylic functional group of APC. FTIR and 1H NMR confirmed the success of surface modification of G5. The primary amino and phosphorylcholine (PC) group numbers of the surface engineered PAMAM dendrimers (G5-PC) were calculated to be 56 and 50 via 1H NMR and potentiometric titration. Cell viability and cell morphology studies indicated that biomimetic phosphorylcholine surface engineering successfully lowered the cytotoxicity of G5 PAMAM dendrimers. The hydrophobic interior of G5-PC was used to incorporate anti-cancer drug Adriamycin (ADR) and the G5-PC showed sustained releasing behavior for ADR. Cell morphology and viability tests indicated that the drug-loaded G5-PC conjugate could effectively enter the cancer cells and inhibit the growth of cancer cells. Biomimetic phosphorylcholine surface engineered PAMAM dendrimers with lowered cytotoxicity and high cellular penetrating ability showed great potential for the biomedical applications as nanocarrier system. [Copyright &y& Elsevier]

Abstract: Invariant natural killer T cells are a unique lymphocyte subtype that can recognize lipid antigens presented by CD1d and release pro-atherogenic cytokines such as interferon-gamma. We studied the importance of iNKT cells, other lymphocyte cell types and CD11b in the peripheral blood of patients diagnosed with acute myocardial infarction (AMI) before and after primary coronary stenting. Lymphocyte population profiles and CD11b were compared between patients with AMI and healthy control subjects using flow cytometry. Both the absolute number and cell fractions of iNKT, CD3+CD4+ lymphocytes were significant lower in AMI patients than health controls. The cell fraction of NK cells was also reduced, while there was a significant increase in the cell fractions and absolute numbers of CD3+CD8+ lymphocytes, B lymphocytes and mean fluorescence intensity values of labeled CD11b. The number of iNKT cells was significantly and positively correlated with cholesterol and low-density lipoprotein levels in blood samples from AMI patients before primary coronary stenting. Logistic regression analysis demonstrated that the absolute number of iNKT cells was a significant independent predictor for restenosis during the 243day post-operative follow-up. This study demonstrates that iNKT cell number may be a useful predictor of clinical outcome in AMI patients with primary coronary stenting. [Copyright &y& Elsevier]

This study focused on surface waters from three small creeks, within the Seine River watershed, which are characterized by different land-uses, namely forested, agricultural and urban. Silver nanoparticles (Ag-NPs) in these waters were detected and quantified by single-particle ICPMS during one-year of monthly sampling. Their temporal and spatial variations were investigated. Ag-NPs, in the three types of surface water, were found to range from 1.5 × 107 to 2.3 × 109 particles L−1 and from 0.4 to 28.3 ng L−1 at number and mass concentrations, respectively. These values are in consistent with the very few previous studies. In addition, the role of factors driving process and potential sources are discussed with correlations between Ag-NPs concentrations and biogeochemical parameters, like dissolved organic carbon concentration and divalent cations concentrations. For the forested watershed NOM controls the stability (number and mass) of the Ag-NPs as recently observed in the field in lake water in Germany. In the case of the agricultural and urban watersheds major cations such as Ca would control the number and mass of Ag-NPs. Dilution processes are rejected as conductivity and Cl− ions do not show significant correlations with Ag-NPs or other major geochemical parameters. The specific exportation rates of Ag-NPs for artificial, agricultural and forested areas were calculated based on the monthly data for the full year and are equal to 5.5 ± 3.0, 0.5 ± 0.3 and 0.2 ± 0.2 gy−1km−2, respectively. These data suggest a constant release of Ag-NPs from consumer products into freshwaters in artificial areas, for instance, from textiles, washing machines, domestic tap-water filters, outdoor paints. These first data of Ag-NPs fluxes in surface waters of France enlarge the very limited database of field measurements. Moreover, for the first time, the influence of time, land-use and aquatic geochemistry parameters on Ag-NPs in real natural water samples is reported. It is also helpful to further understand the fate and the process of Ag-NPs in natural waters, as well as to the ecotoxicity studies in real-world environment. • In a one-year study we report Ag-NPs occurrence in 3 watersheds with different land-uses. • Concentrations range from 1.5 × 107 to 2.3 × 109 particles L−1 and from 0.4 to 28.3 ng L−1. • There is a strong correlation between DOC and Ag-NPs concentrations in forested water. • An annual export rate of 2.3 ± 1.3 g/year/km2 is obtained for the urban watershed. • Agricultural and forested watersheds have smaller rates: 0.3 ± 0.3 g/year/km2. [ABSTRACT FROM AUTHOR]

In this study, a kind of waterborne polyurethane coating material with excellent water resistance performance has been prepared through the cross-linking of waterborne polyurethane (WPU) with a combination of multiple blocking agents applied. And then, with modified SiO 2 aerogel (SSA) added into the water-resistant waterborne polyurethane (FWPU), the highly water-resistant transparent waterborne polyurethane thermal insulation coating material was obtained. Basically, the addition of SSA has no impact on the water resistance performance of FWPU. Furthermore, through the proper addition of SSA, the adhesive force and heat insulation performance of the composite coating material can be improved. When the SSA content accounts for a 15 % solid content of FWPU, the composite coating present the best comprehensive performance. This highly water-resistant transparent waterborne polyurethane thermal-insulation coating material has the prospect of being used as thermal insulation surface coating on transparent materials such as building glass. • The synergy of multiple self-crosslinking on improving water resistance of waterborne polyurethane coatings were studied. • Thermal insulation performance of waterborne polyurethane coatings are improved by adding SiO 2 aerogel. • Hardness and adhesion of waterborne polyurethane coatings are also improved by control the amount of SiO 2 aerogel. [ABSTRACT FROM AUTHOR]

Silica nanotubes were prepared using the gelatin nanofibers as novel sacrificed template via a sol-gel route with a subsequent calcination process. FT-IR spectrum showed that the siloxane bonds (Si-O-Si) were involved in the silica nanotubes. SEM observations showed that the silica nanotubes had an average diameter of 742 ± 82 nm with a hollow cavity of 513 ± 68 nm. The formation of the tubular hollow structure was attributed to the removal of gelatin template. After soaked in the solution of tetracycline hydrochloride (TH, one of the representative antibiotics) as model drug, the silica nanotubes favored the adsorption of TH with the loading efficiency of 38%. A sustained release behavior of TH was observed as the TH-loaded silica nanotubes were soaked in the phosphate buffer saline. The released TH was biologically active to strongly inhibit the growth of bacterial E. coli . [ABSTRACT FROM AUTHOR]

Carbon-based magnetic absorbents are widely used for electromagnetic wave absorption (EMWA) rubber composites due to the dual electromagnetic wave loss effects of dielectric loss and magnetic loss. Co/Co 3 O 4 nanoparticles decorated carbon nanofiber aerogels (C/Co/Co 3 O 4 aerogels) are prepared by carbonization of nanofiber network structure agarose/cobalt acetate. The in-situ synthetic C/Co/Co 3 O 4 aerogels with carbon nanofiber network structure and controllable particle size of Co/Co 3 O 4 nanoparticles that have the good conductivity and tunable magnetic property increasing both of the dielectric loss and magnetic loss capabilities, which can improve the EMWA performance. Lightweight EMWA rubber composites with 3.75 wt% C/Co/Co 3 O 4 aerogels have the same density as that of silicone rubber (PDMS), the effective absorption band (EAB, frequency for reflection loss<−10 dB) of PDMS/Co-1.25 is aways above 3 GHz when the thickness is bigger than 2.5 mm, the max EAB is 4.24 GHz at the thickness of 2.74 mm. The radar cross section (RCS) reduction can achieve 14 dBm2 when the perfectly electrically conductive (PEC) is covered by a 4.5 mm thick PDMS/Co-1.25. The intensity distributions of electric field, magnetic field and power loss density of EMWA rubber composites are exhibited based on the electromagnetic parameters. The rubber composites based on C/Co/Co 3 O 4 aerogels can be used as lightweight flexible EMWA materials. [Display omitted] • C/Co/Co 3 O 4 aerogels with in-situ synthetic Co/Co 3 O 4 nanoparticles on carbon nanofibers are prepared. • Magnetic properties of C/Co/Co 3 O 4 aerogels are investigated based on the characterizations of microstructure morphology and composition. • Lightweight EMWA rubber composites with 3.75 wt% C/Co/Co 3 O 4 aerogels have a maximum effective absorption band of 4.24 GHz. • The power loss density and radar cross section of lightweight EMWA rubber composites are studied. [ABSTRACT FROM AUTHOR]

Combination of silica component with other materials is one of the current strategies to design bone regenerative materials. In this study, novel reduced graphene oxide (RGO)–aminosilica hybrid nanosheets with enhanced osteo-compatibility were synthesized from a mixture of 3-aminopropyltriethoxysilane (APTES), graphene oxides (GO) and water. The presence of APTES in the mixture not only caused the conversion of GO to RGO, but also led to the hydrolysis and condensation of itself. It was for the first time reported the reducing role of APTES in the conversion of GO to RGO. It was found that the silicon (IV) ions were released from the hybrid nanosheets in a sustained way. The in vitro osteo-compatibility was evaluated by incubating the hybrid nanosheets with osteoblast MC3T3-E1 cells. A water soluble tetrazolium salt assay quantitatively indicated that the hybrid nanosheets had no significant toxicity and exhibited good biocompatibility. An alkaline phosphatase assay quantitatively indicated that the hybrid nanosheets enhanced the osteoblast differentiation compared to the GO nanosheets. An immunochemical assay further qualitatively indicated that the hybrid nanosheets stimulated the production of osteopontin as typical marker for osteoblast differentiation. Thus, the resultant hybrids nanosheets had a potential application in the bone regeneration. [ABSTRACT FROM AUTHOR]

Polyester (PET) fibers must undergo impregnation with a resorcinol-formaldehyde-latex (RFL) solution to ensure efficient adhesion with rubber. However, the harmful, carcinogenic resorcinol-formaldehyde (RF) resin in RFL impregnation solution negatively affects human health. In this paper, PET was pretreated with blocked isocyanate and epoxy resins to activate the fibers, and a new environmentally friendly fiber impregnation coating was developed. In the new impregnation coatings, ethylene glycol diglycidyl ether (EGDE) and m-xylylenediamine (MXDA) were applied to replace the resorcinol and formaldehyde. Moreover, glycidyl methacrylate (GMA) containing epoxy groups and double bonds was introduced to enhance interaction with rubber further, and then styrene-butadiene-vinyl-pyridine (VP) latex was mixed. The results show that the peel strength of the impregnated PET/rubber composites with the new impregnation coatings can reach 14.0 N/mm, representing an increase of 30.8 % compared to that of the sample with the pure RFL impregnation coatings, whose peel strength is only 10.7 N/mm. Furthermore, the mechanism for enhancing the interfacial adhesive properties of PET/rubber composites was performed by analyzing the chemical composition and morphological changes of the impregnated PET surface, as well as the change of sulfur content at the interface of the impregnated PET/rubber composites and the transition gradient of interfacial modulus. [Display omitted] • A multi-component epoxy resin environmentally friendly fiber impregnation coatings was developed. • The new impregnation coatings has even better interfacial adhesive properties compared to the RFL impregnation coatings. • Interfacial elements, structure, and modulus changes of environmentally friendly impregnated coatings were characterized. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anisotropic hydrogels are obtained based on a magnetic field pre-induction strategy. • Oriented nanohybrids impart hydrogels with anisotropic electromechanical properties. • Anisotropic hydrogels exhibit highly accurate multidimensional sensing capability. • It contributes to the integration of strain sensing and magnetothermal physiotherapy. In this study, we present the development of wearable electronic devices with integrated sensing and physiotherapy functionalities, aiming to advance flexible multidimensional strain sensors. The as-developed electronic devices are based on a composite hydrogel with unique anisotropic electromechanical properties and exceptional magnetothermal capabilities. Specifically, two-dimensional nanohybrids possessing both conductive and magnetic properties are induced to align orientationally within the polyvinyl alcohol (PVA) network through a magnetic field pre-induction strategy, resulting in the conductive hydrogels with anisotropic structures. The as-optimized composite hydrogel demonstrates distinct conductivities in the parallel and vertical directions, enabling the creation of a multidimensional strain sensor. This sensor is capable of accurately sensing strains in orthogonal directions, with distinguishable gauge factors (GF ∥ = 3.20, while GF ⊥ = 1.78) within the tensile strain range of 0 ∼ 60%. Additionally, the strain sensor exhibits a relatively fast response time (t ∥ = 74.47 ms, t ⊥ = 157.63 ms). Moreover, the composite hydrogel exhibits excellent magnetothermal physiotherapy capabilities, making it suitable for therapeutic applications. Furthermore, the conductive hydrogel can be assembled into a 3D distribution array, enabling the detection of both the magnitude and spatial distribution of stress. In summary, the anisotropic conductive hydrogel shows promise as a next-generation, multidimensional flexible strain and stress sensors with rehabilitation assistant functions. [ABSTRACT FROM AUTHOR]

Abstract A synthesis of cephalostatin 1 from hecogenin is described in detail. The gram-scale synthesis of south part features a Baeyer–Villiger oxidation of hecogenin to 16,20-diol, a selective oxidation of C16 OH with Dess–Martin periodinane, a Rh(I)-catalyzed C15 C16 double bond shift to C14 C15 position, and a Hg(OAc) 2 -mediated spiroketal formation from cyclic enol ethers with alkenyl side chain at 2-position. Key transformations in the synthesis of north part, also on gram scale, include an abnormal Baeyer–Villiger oxidation of hecogenin to the corresponding dinorcholanic lactone, where a catalytic amount of iodine acts as a traceless and catalytic switch, an umpolung of steroidal 22-aldehyde to forge C22 C23 bond with good stereochemical control, a cascade spiroketal-forming process to establish DEF rings in one operation, and a selective oxidation of C3 OH. There are also other noteworthy transformations that, although not used in our final route, are valuable and could be applied to other syntheses, including: intra- or intermolecular S N 2′ processes of C14-heteroatom-substituted C15 C16 alkenes, an unprecedented rearrangement of β-adduct of D-ring dienes and singlet oxygen, a chelation-controlled methylallylation of C23 aldehyde, and so on. Graphical abstract Image 1 Highlights • Mercuric acetate promotes cyclic enol ethers with alkenyl chain at 2-position to form spiroketals. • Iodide-catalyzed abnormal Baeyer-Villiger oxidation of steroidal sapogenin delivered dinorcholanic lactone. • β-Adduct of D-ring diene with singlet oxygen rearranged to an unprecedented tricyclic structure. • With a leaving group at C14, C15 C16 double bond undergoes S N 2′ reaction inter- or intramolecularly. • Both spiroketals of cephalostatin 1 are thermodynamically favorable. [ABSTRACT FROM AUTHOR]

Abstract Sn 2 Nb 2 O 7 photoanode has been fabricated by the electrophoretic deposition method and its photoelectrochemical (PEC) properties were studied carefully. The energy band structure of Sn 2 Nb 2 O 7 was analyzed by Mott-Schottky plots, the results show that its energy band structure matches the requirement of PEC water splitting, the low absolute onset potential of −0.12 V vs NHE achieved with the Sn 2 Nb 2 O 7 /Co-Pi. The influence of film thickness and calcination temperature on the photocurrent of Sn 2 Nb 2 O 7 was studied, and an optimum condition was identified. The obtained maximum photocurrent density was 0.18 mA/cm2. After surface modification with the water-oxidation electrocatalyst Co-Pi, the photocurrent density was improved furtherly, reached to 0.24 mA/cm2, and the incident photon current efficiency (IPCE) value increased to 2.25% when irradiated by 365 nm light. Water oxidation was carried out over Sn 2 Nb 2 O 7 photoanode, the evolved oxygen reached to 3.5 μmol within 100 min at the experimental conditions. Electrochemical impedance spectroscopy has been performed to investigate the kinetics of electrolyte and electrode interface. Highlights • Sn 2 Nb 2 O 7 photoanode with enhanced PEC performance was obtained. • The conduction level of Sn 2 Nb 2 O 7 was confirmed by Mott-Schottky plot. • The max IPCE of Sn 2 Nb 2 O 7 /Co-Pi reached to 2.25%. • Oxygen production was realized on Sn 2 Nb 2 O 7 under illumination. [ABSTRACT FROM AUTHOR]

In this study, Ag-decorated apatite nanosheet-coated silica nanofibers (Ag-Ap-Si NFs) with enhanced anti-bacterial and photo-catalytic properties were synthesized through incubation of apatite nanosheet-coated silica nanofibers (Ap-Si NFs) in the suspension of chitosan-stabilized Ag nanoparticles (NPs). SEM observations showed that Ag-Ap-Si NFs had the diameter of 840–2340 nm and possessed a hierarchical structure. TEM observations showed the surface of Ag-Ap-Si NFs was constructed by the composites of apatite nanosheets with the thickness around 10 nm and Ag NPs with the size of 5–20 nm. It was found that Ag-Ap-Si NFs showed enhanced anti-bacterial property to inhibit the growth of both Escherichia coli and Staphylococcus aureus and superior photo-catalytic activity for reduction of 4-nitrophenol in the presence of NaBH 4 . The present Ag-Ap-Si NFs would be applicable as multi-functional materials with both photo-catalytic and anti-bacterial properties for wastewater treatment at weak acidic and basic pH. [ABSTRACT FROM AUTHOR]

Phytoextraction is an environmentally friendly phytoremediation technology that can reduce the total amount of heavy metals (HMs) in the soil. Hyperaccumulators or hyperaccumulating transgenic plants with biomass are important biomaterials for phytoextraction. In this study, we show that three different HM transporters from the hyperaccumulator Sedum pumbizincicola , SpHMA2, SpHMA3, and SpNramp6, possess Cd transport. These three transporters are located at the plasma membrane, tonoplast, and plasma membrane, respectively. Their transcripts could be strongly stimulated by multiple HMs treatments. To create potential biomaterials for phytoextraction, we overexpressed the three single genes and two combining genes, SpHMA2 & SpHMA3 and SpHMA2 & SpNramp6 , in rapes having high biomass and environmental adaptability, and found that the aerial parts of the SpHMA2 -OE3 and SpHMA2&SpNramp6 -OE4 lines accumulated more Cd from single Cd-contaminated soil because SpNramp6 transports Cd from root cells to the xylem and SpHMA2 from the stems to the leaves. However, the accumulation of each HM in the aerial parts of all selected transgenic rapes was strengthened in multiple HMs-contaminated soils, probably due to the synergistic transport. The HMs residuals in the soil after the transgenic plant phytoremediation were also greatly reduced. These results provide effective solutions for phytoextraction in both Cd and multiple HMs-contaminated soils. [Display omitted] • Transgenic rapes to remediate heavy-metal contaminated soil were created. • Sedum SpHMA2, SpHMA3, and SpNramp6 responded to Cd, Pb, Cu, Mn, and Zn stress. • Transgenic SpHMA2 and SpHMA2 & SpNramp6 rapes accumulated more Cd in shoots. • The synergistic transport of multiple HMs to shoots appeared in transgenic rapes. • The transport mechanism of SpHMA2, SpHMA3, and SpNramp6 was deduced. [ABSTRACT FROM AUTHOR]

In this study, novel flower-like apatite@Au composite nanosheet spheres were synthesized through in situ immobilization of Au nanoparticles on the bone-like apatite nanosheets. SEM observations indicated that the as-synthesized spheres had a diameter of 0.8–3 µm and was constructed by numerous primary apatite nanosheets with the thickness around 10 nm. TEM images showed that ∼10 nm Au nanoparticles were immobilized on the apatite nanosheets. When incubated with the mixture of 4-nitrophenol and NaBH 4 , the resultant apatite@Au composite nanosheet spheres exhibited the superior photo-catalytic activity for reduction of 4-nitrophenol. [ABSTRACT FROM AUTHOR]

Gelatin/hydroxyapatite (HAp) composites are of great interest in the biomedical applications because of their excellent biocompatibility, biodegradability, and bioactivity. However, little attention has been paid to synthesis of the gelatin/HAp composites with photo-thermal property. In this study, near-infrared (NIR) responsive gold nanorod (GNR) doped gelatin/HAp composite microspheres were synthesized via an emulsion technique and their microstructure and NIR-responsive photo-thermal property were investigated. SEM observations showed that the composite microspheres were spherical and their diameter was ranged from 10 to 50 µm. XRD patterns showed that the composite microspheres presented the typical diffraction peaks of HAp and GNR components. FT-IR spectra showed that P-O-P bonds, -COOH groups and –NH 2 groups were involved in the composite microspheres. Under an 808-nm NIR light irradiation, the temperature of the suspension of composite microspheres was increased from 37 °C to 42 °C due to the presence of GNR component, indicating that the composite microspheres possessed NIR-responsive photo-thermal property. [ABSTRACT FROM AUTHOR]

Natural products are still the principal source of drug candidates or leading compounds in new drug discovery. It is an important challenge to innovate and construct a rapid and efficient research system of natural products. Microfluidic technology can miniaturize the analytical process such as sample pretreatment, reaction, separation and detection onto a single chip with multichannel. It is particularly suitable for the analysis and screening of trace natural products, with the benefits of rapid analysis, high information content, and low fabrication cost. This review comprehensively summarized the natural products-related design of the microfluidic device and the typical applications in the analysis, activity/toxicity evaluation, ADME study of natural products. We also discussed the limitations and challenges in previous studies. Finally, we proposed future research directions, development trends and potential applications of microfluidic device in natural products research. • Various fabrications of microfluidic chips for natural products research have been presented. • Applied in assay, activity screening, toxicity evaluation, ADME study of natural products. • Miniaturized screening chips showed rapid analysis, high sensitivity, high throughput. [ABSTRACT FROM AUTHOR]

For in-situ Ti 48 Zr 20 Nb 12 Cu 5 Be 15 metallic glass matrix composites (MGMCs) upon cold rolling, the yield strength is obviously enhanced, and the plasticity instability is effectively alleviated. The increase in yield strength in such kinds of composites is due to the fact that the work hardening of dendrites overwhelms the softening of the amorphous matrix. A quantitative model of predicting yield strengths with rolling straining in MGMCs is successfully established. This provides useful guidances for structural applications of ductile MGMCs. • A quantitative model is established to predict the yield strengths for in-situ dendrite-reinforced MGMCs upon cold rolling. • Proper cold rolling not only improves the yield strength of the current MGMCs, but also relieves the plasticity instability. • The plastically deformed dendrites have reduced ability to inhibit shear band expansion due to work hardening. • The amorphous matrix would be locally softened due to the generation of shear bands. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C 3 N 4) is a promising material for photocatalytic environmental purification. However, the application of g-C 3 N 4 has been limited by its synthetic processes, where a low-cost and high-activity synthetic method could promote its application. Here, by utilizing formaldehyde and changing the thermal condensation processes, g-C 3 N 4 with a large specific surface area was obtained, and its photocatalytic activity was 12.3 and 6.5 times that of pristine g-C 3 N 4 for photocatalytic organic pollutant degradation and photocatalytic water splitting, respectively. The enhanced photocatalytic performance can be attributed to the large specific surface area, which reached 137.3 m2/g, as well as the improved efficiency of the separation and transfer of charge carriers. Moreover, the additional trace amounts of formaldehyde can increase the yield of g-C 3 N 4 , and the yield reached 21%, which is 7 times that obtained with traditional thermal condensation processes. • The yield of g-C 3 N 4 reached 21% by heating formaldehyde-treated melamine. • The synthetic method has easy scale-up, low cost, and environmental friendliness. • The photocatalytic activity of the obtained g-C 3 N 4 was increased by 12.3 times. [ABSTRACT FROM AUTHOR]

A new precursor was developed for the preparation of graphitic carbon nitride (g-C 3 N 4) with a large specific surface area and N vacancies. The SEM and TEM results show that the obtained samples have porous nanosheet structure, XPS, EPR and UV–Vis spectra indicate N vacancy defects existed in the g-C 3 N 4. During the synthesis process, glyoxylic acid inhibited the condensation of melamine, thus increasing the porosity of g-C 3 N 4 , generating abundant defects, and improving yield. Under light irradiation, g-C 3 N 4 samples prepared by glyoxylic acid mediated melamine shown enhanced photocatalytic activities in gaseous organic pollution photodegradation. This study developed a potential agent for producing inexpensive and highly active g-C 3 N 4 photocatalysts. The large specific surface area porous g-C 3 N 4 sheets with nitrogen vacancies have been fabricated successfully by using a glyoxylic acid treated melamine. This method is a high-yield and low-cost synthetic pathway to form large specific surface area porous g-C 3 N 4 nanosheet. The photocatalytic activity of g-C 3 N 4 was enhanced in gaseous pollution photodegradation. Image 1 • Glyoxylic acid results in harvesting specific surface area, and generating defects in g-C 3 N 4 simultaneously. • Glyoxylic acid reduces the cost of g-C 3 N 4 greatly by increase the yield. • Enhanced activities in gaseous iso-propanol photodegradation and photoelectric properties. [ABSTRACT FROM AUTHOR]

Nano-sized amorphous calcium carbonate (ACC) have a great potential for drug transport and drug delivery because of their high drug loading capacity, excellent biocompatibility and biodegradability. However, ACC is the thermodynamically least stable phase of calcium carbonate, and such thermal metastability often transforms it into more stable vaterite or calcite phases, so the inhibition of the phase transformation of ACC is of great significance for its application in drug delivery systems. Herein, phosphate as a morphology controlling additive was introduced to stabilize the metastable ACC. The results showed that the composite nanoparticles (named here the ACCP) with narrow size distribution located at approximately 128 nm (measured by dynamic light scattering) were obtained, when Ca2+ concentration and C/P were 10 mM and 7/3 respectively, prepared at 30 °C for 10 min. The powdered X-ray diffraction (XRD) results showed that phosphate has an excellent ability to stabilize ACC, and even after storage for 60 days at room temperature, the structure of ACCP remains amorphous. The in vitro drug release tests showed that ACCP nanoparticles had a high curcumin (Cur) loading capacity and a sustained drug release property. Moreover, the 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH) radical scavenging activity assay showed that ACCP-encapsulating strategy could effectively prevent the decomposition of Cur. In vitro cytotoxicity tests demonstrated that the resultants have excellent biocompatibility. Therefore, the as-prepared ACCP nanoparticles are promising for drug delivery applications. • The nano-sized ACCP particles were successful prepared using phosphate as a stabilizer. • Cur-loaded ACCP shows favorable Cur release properties. • The ACCP-Cur showed a promising of DPPH free radicals scavenging capacity. • Cytotoxicity tests showed that ACCP and ACCP-Cur have low and high cells toxicity, respectively. [ABSTRACT FROM AUTHOR]

In this study, novel dendritic TiO 2 nanofibers (D-Ti NFs) with ultrahigh surface area were for the first time synthesized through in situ hydrothermal treatment of the electrospun TiO 2 nanofibers (E-Ti NFs) and their microstructure, formation mechanism, in vitro biocompatibility and drug delivery property were investigated. SEM observations showed that D-Ti NFs had dendritic and fibrous morphology with the controllable diameter of 899 ± 26 nm to 1955 ± 64 nm. TEM observations showed the individual D-Ti NF was assembled by numerous primary nanowires with the diameter of 7 ± 1 nm. XRD pattern showed that the D-Ti NFs displayed the characteristic peaks at 24.1°, 28.1°, and 48.3°, all of which were assigned to hydrogen titanium oxide hydrate. BET measurement indicated that D-Ti NFs had the ultrahigh specific surface area of 213.41 m2/g. D-Ti NFs showed good in vitro biocompatibility when exposed to Hela cells. After soaked in solution of tetracycline hydrochloride (TH, one of the representative antibiotics, model drug), D-Ti NFs supported the loading of TH with the loading efficiency of 63.73 ± 4.61%. TH-loaded D-Ti NFs supported a sustained release model for TH when immersed in the phosphate buffer saline. After separately incubated with two representative types of bacteria: Escherichia coli and Staphylococcus aureus , TH-loaded D-Ti NFs showed excellent antibacterial property to inhibit the growth of the bacteria, indicating that the released TH was biologically active. • Dendritic TiO 2 nanofibers with high surface area were facilely synthesized. • They were biocompatible when exposed to Hela cells. • They supported the loading and sustained release behavior of drugs. • They well maintained the biologic activity of loaded drugs. [ABSTRACT FROM AUTHOR]