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Aflatoxins are widely occurring food contaminants that are particularly harmful to dairy products and cows. The plant polyphenol resveratrol has been reported to have a good effect on increasing the resistance of cells toward toxins. Therefore, we measured the effects of aflatoxin B1 and resveratrol on the viability of the MAC-T cow mammary epithelial cell line. The appropriate treatment concentrations were assayed (12.81 μM aflatoxin B1 and 43.81 μM resveratrol) to verify the protective effect of resveratrol toward mammary epithelial cells. The results showed that resveratrol alleviates aflatoxin B1-induced cytotoxicity, including the increase in ROS and the decrease in mitochondrial membrane potential (MMP) and apoptosis in MAC-T cells. The expression of mRNA transcripts (including Nrf2, Keap1, NQO1, HO-1, SOD2 and HSP70) for components of the Nrf2 signaling pathway was evaluated by real-time fluorescent quantitative PCR, with resveratrol also exhibiting a good regulatory effect. Thus, resveratrol was shown to have an ameliorating effect on aflatoxin toxicity in MAC-T cells. • Resveratrol can recovery the MAC-T cell viability decline induced by AFB1. • Resveratrol inhibits AFB1-induced apoptosis in the MAC-T cell. • Resveratrol may play positive roles via Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract Cobalt-free Li and Mn-rich layered cathode materials are promising for next generation lithium ion batteries due to their high specific capacity and low cost. However, these materials are facing serious issues, such as structural collapse due to volume shrinkage during Ni2+ oxidation to Ni4+ and oxygen vacancy generation over 4.5V. In this work, we report a strategy to address the issue of volume shrinkage caused by structural deformation via constructing a large-size rigid frame by simultaneously doping inactive and large radius atoms of Cd and S. This strategy significantly reduces the volume shrinkage when fully delithiated relative to the pristine material. The Cd- and S-doped cathode materials present a highly reversible structure, which were determined by using HAADF-STEM and in-situ XRD characterization. The doped Cd and S atoms act as supporting atoms and synergistically enlarge the layer spacing of crystalline from 0.455 to 0.483 nm. The in-situ XRD monitors the structural changes in real time during charging and discharging processes, further verifying structural stability during cycling. Due to the unique structural properites, an initial capacity of 268.5 mAh g−1 at 0.1 C along with a good rate capacity of 153.8 mAh g−1 at 5 C were achieved. Also, a capacity of 243.4 mAh g-1 at 0.1 C over 80 cycles indicate good cyclic stability of the co-doped Li- and Mn-rich layered cathode. Graphical abstract fx1 Highlights • Li and Mn-rich layered cathode material is co-doped with large radius inactive cation and anion. • A large layer spacing of 4.83 nm is obtained and retained stable after 100 cycles. • Mechanisms of structural stability during cycles has been elucidated by using HAADF-STEM and in-situ XRD. • A capacity of 153 mAh g−1 at 5 C is obtained with a retention of 84.4% after 200 cycles at 1 C. [ABSTRACT FROM AUTHOR]

Background: Cardiovascular disease is one of the most concerning chronic diseases in the world. Many studies have shown that platelet overactivation is a very important factor in the occurrence and development of cardiovascular diseases. At present, the widely used antiplatelet drugs have some defects, such as drug resistance and adverse reactions.Purpose: The purpose of this article is to summarize the main mechanisms and pathways of platelet activation, the main targets of antiplatelet aggregation, and the antiplatelet aggregation components of natural drugs and their mechanisms of action to provide new research ideas for the development and application of antiplatelet drugs.Study Design and Methods: In this review, we systematically searched the PubMed, Google Scholar, Web of Science, and CNKI databases and selected studies based on predefined eligibility criteria. We then assessed their quality and extracted data.Results: ADP, AA, THR, AF, collagen, SDF-1α, and Ca2+ can induce platelet aggregation and trigger thrombosis. Natural drugs have a good inhibitory effect on platelet activation. More than 50 kinds of natural drugs and over 120 kinds of chemical compounds, including flavonoids, alkaloids, saponins, terpenoids, coumarins, and organic acids, have significantly inhibited platelet activation activity. The MAPK pathway, cGMP-PKG pathway, cAMP-PKA pathway, PI3K-AKT pathway, PTK pathway, PLC pathway, and AA pathway are the main mechanisms and pathways of platelet activation.Conclusion: Natural drugs and their active ingredients have shown good activity and application prospects in anti-platelet aggregation. We hope that this review provides new research ideas for the development and application of antiplatelet drugs. [ABSTRACT FROM AUTHOR]

• Shear capacities of AL- and steel-timber joints by 1-row screws are the same. • Capacity of AL-timber joints by 3-row screws is not reduced when two plastic hinges. • The discrimination coefficient is introduced to predict failure modes of the screws. Aluminum alloy has significant advantages in reducing self-weight and improving the corrosion resistance compared with steel. The performance of the interface between timber and H-shaped aluminum alloy beams is the key to designing aluminum-timber composite beams. Twelve groups of double-shear tests were conducted in this paper to investigate the influences of glulam strength, the type and size of connectors, and the row number of connectors on shear capacity, and the failure modes of connections were evaluated. The results have shown that, compared with the specimens connected by screws, the bolt heads of the specimens connected by bolts tended to cause local crushing failure of the glulam. There is negligible difference between the shear capacities of aluminum-timber and steel-timber connection when connected by single-row screws. For the group effect of the screws, the reduction of shear capacity of aluminum-timber connections is slightly higher than that of steel-timber connections when connected by multi-row screws. The shear capacity of aluminum-timber connections with multi-row screws needs to be reduced when one plastic hinge appears in the screws (failure mode II). It does not need to be reduced when two plastic hinges appear in the screws (failure mode III), and the theoretical value has a large safety margin. The length-to-diameter ratio λ is the main factor affecting the failure modes of the screws, and the coefficient λ y is introduced to discriminate the failure modes. [ABSTRACT FROM AUTHOR]

Abstract: Water-soluble titanate nanotubes (TNTs) with temperature-responsive shells were synthesized by grafting poly(N-isopropylacrylamide) (PNIPAAm) from TNTs via surface atom transfer radical polymerization (ATRP) using ATRP agent functionalized TNTs as macroinitiator. Proton Nuclear magnetic resonance spectroscopy (1H NMR), Fourier-transform infrared (FT-IR) and thermogravimetric analyses (TGA) results prove the successful graft of PNIPAAm chains from TNTs. TGA shows that the amount of PNIPAAm grown from the TNTs increased with the increase of monomer/initiator ratio. Transmission electron microscope (TEM) measurements displays the obtained TNTs-g-PNIPAAm nanohybrids have a core–shell structure of TNT cores and PNIPAAm shells. In addition, the functional nanotubes demonstrate a reversible low critical solution temperature (LCST) transition with the increase of solution temperature. The synthetic method presented here can also be extended to graft other stimuli responsive polymers from TNTs. [Copyright &y& Elsevier]

Abstract: In recent years, polymer microcapsules have attracted more and more attention because of their specific properties and applications in encapsulation and drug delivery. Great effort has been made to investigate the preparation methods, structure controls as well as the property designs for the polymer microcapsules. In this work, we reported an effective route for the preparation of poly(β-hydroxybutyrate) (PHB) and poly(lactic acid) (PLA) hollow spheres with controlled wall thickness, which involves the graft polymerization of the biodegradable polymers from the surface of silica spheres followed by removing the template cores. Nuclear magnetic resonance spectroscopy (NMR), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscope (TEM) have been used to prove the structure of the hollow sphere and the intermediates. The result reveals that with the increase of reaction time the wall thickness of the hollow sphere will increase gradually. [Copyright &y& Elsevier]

Decreasing gas penetration has noticeable effects on the durability and performance of Nafion based proton exchange membranes (PEMs). Experimental studies showed that adding imidazolyl groups into Nafion could reduce the hydrogen permeation in the membrane, while causing the substantial increase in power density. Nonetheless, the microscopic mechanism of doping on the reduction of hydrogen permeation is remain unclear. In this work, molecular dynamics simulation was performed to understand the transport behaviors of hydrogen in polyvinylimidazole (PVMZ)/Nafion composite membranes at the molecular level. The simulation results indicate that there are different degrees of effects about the polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion at low and high hydration levels. With the increase of water content, the hydrogen molecules will migrate from the polymer phase to the polymer/water interface in Nafion and PVMZ/Nafion membranes. At low water content, the more free volume and the more pores in Nafion membrane are conducive to the diffusion of hydrogen than that in PVMZ/Nafion membrane to a greater extent. For the aqueous domain, the smaller and the rougher surface of water clusters in PVMZ/Nafion membranes have a certain limiting effect on the diffusion of hydrogen molecules than that in Nafion membranes at high water content. Consequently, at low water contents (λ ≤ 9), the self-diffusion coefficient of hydrogen (D H2) increases slowly from 0.55 to 1.01 (× 10−5 cm2/s) in Nafion membrane and from 0.26 to 0.53 (× 10−5 cm2/s) in PVMZ/Nafion membrane. In contrast, at high water contents (λ ≥ 9), the D H2 increases rapidly from 1.01 to 2.35 (× 10−5 cm2/s) in Nafion membranes and from 0.53 to 1.74 (× 10−5 cm2/s) in PVMZ/Nafion membranes. The current work can provide a fundamental understanding for experimentally designing new type Nafion based PEMs for hydrogen fuel cells. [Display omitted] • A similar but lower diffusion of hydrogen occurs in PVMZ/Nafion than Nafion under different water contents. • There are different effects for polymer phase and aqueous domain on the diffusion kinetics of hydrogen in Nafion and PVMZ/Nafion. • The hydrogen in Nafion and PVMZ/Nafion tends to migrate toward the polymer/water interface as increasing water content. [ABSTRACT FROM AUTHOR]

Tetra-amido macrocyclic ligand (TAML) activator is a functional analog of peroxidase enzymes, which activates hydrogen peroxide (H 2 O 2 ) to form high valence iron-oxo complexes that selectively degrade persistent aromatic organic contaminants (ACs) in water. Here, we develop quantitative structure–activity relationship (QSAR) models based on measured pseudo first-order kinetic rate coefficients ( k obs ) of 29 ACs (e.g., phenols and pharmaceuticals) oxidized by TAML/H 2 O 2 at neutral and basic pH values to gain mechanistic insight on the selectivity and pH dependence of TAML/H 2 O 2 systems. These QSAR models infer that electron donating ability ( E HOMO ) is the most important AC characteristic for TAML/H 2 O 2 oxidation, pointing to a rate-limiting single-electron transfer (SET) mechanism. Oxidation rates at pH 7 also depend on AC reactive indices such as f m i n − and qH + , which respectively represent propensity for electrophilic attack and the most positive net atomic charge on hydrogen atoms. At pH 10, TAML/H 2 O 2 is more reactive towards ACs with a lower hydrogen to carbon atoms ratio (#H:C), suggesting the significance of hydrogen atom abstraction. In addition, ln k obs of 14 monosubstituted phenols is negatively correlated with Hammett constants ( σ ) and exhibits similar sensitivity to substituent effects as horseradish peroxidase. Although accurately predicting degradation rates of specific ACs in complex wastewater matrices could be difficult, these QSAR models are statistically robust and help predict both relative degradability and reaction mechanism for TAML/H 2 O 2 -based treatment processes. [ABSTRACT FROM AUTHOR]

Abstract: Graft copolymerization of N-vinyl-2-pyrrolidone (NVP) onto 60Co γ-ray pre-irradiated poly (vinylidene fluoride) (PVDF) powder was investigated to find out the relationship between the degree of grafting (DG) and various factors, including monomer concentration, irradiation dose, reaction time, catalyst and so on. The DG can be calculated by comparing the amount of nitrogen element in the resulting copolymer (PVDF-g-PVP) powder with that in PVP on the basis of element analysis. The presence of PVP in the resulting PVDF powder was confirmed by the comparative studies of pristine PVDF and grafted PVDF powder through Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), thermo gravimetric analyzer (TGA) and differential scanning calorimetry (DSC), respectively. When the reaction was performed at the monomer concentration of 20% (vol.) and the absorbed dose of 40kGy for 3h in water, the max. DG of 17.7% was obtained. [Copyright &y& Elsevier]

The experimental results for the behaviour of concrete columns confined by both steel spirals and fibre-reinforced polymer (FRP) are presented. A total of fifty-six columns were investigated experimentally under axial load. The test program involves the number of FRP layers (1 or 2 layers), the type of FRP (CFRP and BFRP), and the spacing of the steel spirals. The test results show that both FRP and steel enhance the ultimate concrete strength and strain. The strength and ultimate deformation ability of the concrete increase as the number of external FRP layers increases or the spacing of steel spirals decreases. The compressive response of concrete columns confined by both steel spirals and FRP shows a similar trend with steel spiral-confined columns after FRP rupture, as determined by the spacing of the steel spirals. The residual strength increases, and the stress degradation rate decreases as the spacing of the steel spirals decreases. A new model is presented for evaluating the axial strength of concrete confined with both FRP and steel, and the model may accurately predict the ultimate strength of FRP-steel-confined concrete with both sufficient and insufficient confinement. [ABSTRACT FROM AUTHOR]

As a means of chemical identification and analysis, Surface enhanced Raman spectroscopy (SERS), with the advantages of high sensitivity and selectivity, non-destructive, high repeatability and in situ detection etc., has important significance in the field of composition detection, environmental science, biological medicine etc. Physical model of coupling effect between different semiconductor substrates and noble metal particles were investigated by using 3D-FDTD method. Mechanism and the effects of excitation wavelength, particle spacing and semiconductor substrate types on the SERS effect were discussed. The results showed that the optimal excitation wavelengths of three noble metals of Ag, Au, Cu, were located at 510, 600 and 630 nm, respectively; SERS effect of Ag, Au, Cu increases with the decreasing of the inter distance of particles, while the distance of the NPs reaches the critical value of 3 nm, the strength of SERS effect will be greatly enhanced. For the four different types of substrate of Ge, Si, SiO 2 (glass) and Al 2 O 3 , the SERS effect of Ag on SiO 2 > Ge > Al 2 O 3 > Si. For Au and Cu nanoparticles, the SERS effect of them on oxide substrate is stronger than that on non-oxide substrate. In order to verify FDTD simulations, taking silver nanoparticles as an example, and silver nanoparticles prepared by chemical method were spinning coating on the four different substrates with R6G as probe molecules. The results show that the experimental results are consistent with FDTD theoretical simulations, and the SERS enhancement effect of Ag-SiO 2 substrate is best. The results of this study have important theoretical significance to explain the variations of SERS enhancement on different noble metals, which is also an important guide for the preparation of SERS substrates, especially for the microfluidics. The better Raman effect can be realized by choosing proper substrate type, particle spacing and excitation wavelength, result in expanding the depth and width of SERS application. [ABSTRACT FROM AUTHOR]

The quest for industrial and biotechnological revolution has been contributed in increasing environmental contamination issues, worldwide. The controlled or uncontrolled release of hazardous pollutants from various industrial sectors is one of the key problems facing humanity. Among them, adverse influences of lead, cadmium, and mercury on human health are well known to cause many disorders like reproductive, neurological, endocrine system, and cardiovascular, etc. Besides their presence at lower concentrations, most of these toxic heavy metals are posing noteworthy toxicological concerns. In this context, notable efforts from various regulatory authorities, the increase in the concentration of these toxic heavy metals in the environment is of serious concern, so real-time monitoring is urgently required. This necessitates the exploration for novel and efficient probes for recognition of these toxic agents. Among various methodologies adopted for tailoring such probes, generally the methodologies, in which changes associated with spectral properties, are preferred for the deceptive ease in the recognition process. Accordingly, a promising modality has emerged in the form of radiometric and colorimetric monitoring of these toxic agents. Herein, we review fluorescent sensor based models and their potentialities to address the detection fate of hazardous pollutants for a cleaner environment. Second, recent advances regarding small molecule and rhodamine-based fluorescent sensors, radiometric and colorimetric probes are discussed. The information is also given on the photoinduced electron transfer (PET) mechanism, chelation enhancement fluorescence (CHEF) effect and spirocyclic ring opening mechanism. [ABSTRACT FROM AUTHOR]

In the present study, we developed a biomimetic injectable hydrogel system based on hyaluronic acid-adipic dihydrazide and the oligopeptide G 4 RGDS-grafted oxidized pectin, in which their hydrazide and aldehyde-derivatives enable covalent hydrazone crosslinking of polysaccharides. The hydrazone crosslinking strategy is simple, while circumventing toxicity, making this injectable system feasible, minimally invasive and easily translatable for regenerative purposes. By varying their weight ratios, the physicochemical properties of the mechanically stable hydrogel system were easily adjustable. Additionally, the preliminary studies demonstrated that chondrocyte behavior was dependent on HA/pectin composition and the presence of integrin binding moieties. Specifically, the incorporation of a certain amount of G 4 RGDS oligopeptide into HA/pectin-based hydrogels could serve as a biologically active microenvironment that supported chondrocyte phenotype and facilitated chondrogenesis. Furthermore, the hydrogel system exhibited acceptable tissue compatibility by using a mouse subcutaneous implantation model. Overall, the novel injectable multicomponent hydrogel presented here is expected to be useful biomaterial scaffold for cartilage tissue regeneration. [ABSTRACT FROM AUTHOR]

As an emerging carbonaceous material, carbon aerogels (CAs) display a great potential in environmental cleanup. In this study, a macroscopic three-dimensional monolithic cobalt-doped carbon aerogel was developed by co-condensation of graphene oxide sheets and resorcinol-formaldehyde resin in the presence of cobalt ions, followed by lyophilization, carbonization and thermal treatment in air. Cobalt ions were introduced as a polymerization catalyst to bridge the organogel framework, and finally cobalt species were retained as both metallic cobalt and Co 3 O 4 , wrapped by graphitized carbon layers. The material obtained after a thermal treatment in air (CoCA-A) possesses larger BET specific surface area and pore volume, better hydrophilicity and lower leaching of cobalt ions than that without the post-treatment (CoCA). Despite of a lower loading of cobalt content and a larger mass transfer resistance than traditional powder catalysts, CoCA-A can efficiently eliminate organic contaminants by activation of peroxymonosulfate with a low activation energy. CoCA-A can float beneath the surface of aqueous solution and can be taken out completely without any changes in morphology. The monolith is promising to be developed into an alternative water purification technology due to the easily separable feature. [ABSTRACT FROM AUTHOR]

• Shear capacities are positively related with the size (R and D) of grout pockets. • Grout pockets enable active control of screw failure modes (double plastic hinges). • Critical length ratio (L 0 / L = 30%) makes tip plastic hinge close to grout pockets. The steel-timber composite floor is an environmentally friendly structural form. The shear connectors between the timber and H-steel are the key to designing the steel-timber composite floors, and the strength and ductility of the connection are directly affected by the failure modes of the connectors. A new connection that anchors the screw tips in the grout pockets is presented in this paper. In this connection, the glulam around the screw tip is removed, and the grout is added after the screws have been tightened in the glulam to form a hybrid anchorage of the grout and glulam to the screw. Nine groups of double-shear tests were conducted to investigate the influences of with or without grout pockets, the size of grout pockets, and the row number of connectors on the performance of steel-timber composite connections. Firstly, compared with the common specimens connected by screws, the screw tips were restrained more firmly in specimens with grout pockets. The peak load F max , initial stiffness k s, 0.4 and ductility D of the specimens with grout pockets were increased by a maximum of 25.2, 55.9 and 33.6%, respectively. Secondly, with the increase in the radius and depth of the grout pockets, the secondary stiffness k s, 0.7 and the peak shear capacity F max of the specimens increased accordingly. Thirdly, after the screw tips were anchored in the grout pockets, the screws stably exhibited the failure mode of double plastic hinges (model III), achieving active control of the failure modes of the screws. There is a critical ratio of grout anchor length to the total length of the screw (L 0 / L) such that the tip plastic hinge is close to the grout pocket. In the end, the shear capacity equation for failure mode of double plastic hinges (model III) in Eurocode 5 can be used to calculate the peak capacity of this new connection, and the calculation results have a large safety margin. [ABSTRACT FROM AUTHOR]

Safflower (Carthamus tinctorius L.) is cultivated in various countries for the flavonoid compounds it contains. These flavonoids have been used in many industries as drugs and/or dyes. Over 60 flavonoids have been isolated from safflower. These flavonoids can be divided into two groups: special and common, both of which are active pharmaceutical ingredients efficacious in the treatment of cardiovascular and cerebrovascular diseases. Gene functions have been studied to figure out the biosynthesis of flavonoids in safflower. However, there is no comprehensive summary of the flavonoids in safflower. Research was recognised through systematic searches of ScienceDirect, PubMed, Web of Science, and CNKI databases by searching terms of " Carthamus tinctorius L.", "safflower", "flavonoid", "pharmacology", and "gene". More than 200 research reports were included after eligibility checks. This study summarizes the application of flavonoids in medicine and other industries. Comprehensively collects the chemical structure information of the two groups of flavonoids, and organic acids, alkaloids, spermidine, polyacetylene, and polysaccharides. The mechanism of two groups of flavonoids in treatment of cardiovascular and cerebrovascular diseases was describe in detail, and pharmacological mechanisms of protecting liver, lung and bone, and anti-cancer and anti-inflammatory were also summarised. Besides, the study updated the latest information on the molecular biology of safflower flavonoids. It is found that two groups of flavonoids in safflower have obvious differences in application, chemical structure, pharmacological mechanism, and biosynthetic pathway. It is hoped that this summative research will provide a new insight to flavonoids research in safflower. [Display omitted] • Flavonoids in safflower classified into two into two groups according to chemical structure in this review. • There are differences in the mechanisms of the two groups of flavonoids in improving cardiovascular and cerebrovascular diseases. • Research progress on special flavonoids' biosynthetic pathway in safflower was analysed. [ABSTRACT FROM AUTHOR]

Abstract: A novel water-soluble copolyamide based on Nylon 66 was synthesized via solution-melt polycondensation of hexanedioic acid and sodium 5-sulfoisophthalate with 1,6-diaminohexane. The chemical structures of the products were ascertained by various spectroscopic techniques (FT-IR, Raman, and 1H NMR). The thermal properties of the polyamides under consideration were measured by TGA and DSC. According to the temperature dependence of FTIR spectra, it was found that the average strength of the intermolecular hydrogen bond of the water-soluble copolyamides becomes weak with increasing the temperature. It was found that the obtained random copolyamides could self-assemble into spherical micelles in aqueous solution with the size dependent on the hydrophilic fraction according to the DLS and TEM measurements. [Copyright &y& Elsevier]

Abstract: Polymeric micelles are recognized as very promising nanocarriers for small-molecule drugs, DNA, and proteins delivery. Polyphosphates are an important class of eminent biomaterials and widely used in biomedicine due to their good biocompatibility, biodegradability, and flexibility in adjusting the pendant structures. Here, some full-polyphosphate nanocarriers have been constructed successfully through self-assembly of amphiphilic hyperbranched multiarm copolymers (denoted as HPHEEP-star-PPEPs). The hydrophilic core and hydrophobic multiarm of HPHEEP-star-PPEPs are composed by hyperbranched and linear polyphosphates respectively. HPHEEP-star-PPEPs can self-assembly into nanocarriers in aqueous media with controlled size from 48 to 74nm by conveniently adjusting the length of hydrophobic arm. These nanocarriers possess excellent biocompatibility against NIH 3T3 cells and are easily internalized by vivid cells. Chlorambucil-loaded nanocarriers were investigated for proliferation inhibition of an MDA-MB-231 breast cancer cell line in vitro, and the chlorambucil dose required for 50% cellular growth inhibition was found to be 3μg/mL. [Copyright &y& Elsevier]

Abstract: A drug nanocarrier has been constructed through self-assembly of phospholipid analogous hyperbranched polymers (HPHEEP-alkyls) which contain a polar hyperbranched polyphosphate headgroup and many aliphatic tails. HPHEEP-alkyls were synthesized by self-condensing ring-opening polymerization of 2-(2-hydroxyethoxy)ethoxy-2-oxo-1,3,2-dioxaphospholane and then capped with palmitoyl chloride. Benefiting from the amphiphilic structure with the hydrophilic core and many hydrophobic tails, HPHEEP-alkyls were able to self-assemble into nanomicelles in aqueous media. Importantly, the size of the nanomicelles could be controlled conveniently from 98 to 215nm by adjusting the capped fraction of the hydroxyl groups with hydrophobic palmityls. The excellent biocompatibility of these nanomicelles was confirmed by methyl tetrazolium assay and acridine orange/ethidium bromide double staining against COS-7 cells. Confocal laser scanning microscopy and flow cytometry analysis demonstrated their good cell permeability, i.e. these nanomicelles were easily internalized by vivid cells and mainly located in the cytoplasm rather than nucleolus. Chlorambucil-loaded nanomicelles were investigated for proliferation inhibition of a MCF-7 breast cancer cell line in vitro, and the chlorambucil dose required for 50% cellular growth inhibition was found to be 5μg/mL. All of these results indicate that HPHEEP-alkyls nanomicelles can be used as safe and promising drug nanocarriers. [Copyright &y& Elsevier]

Abstract: Worm-like mesoporous silica with various pore sizes has been prepared successfully templated by a multiarm hyperbranched copolyether (PEHO-star-PPO). The pore size of the resultant mesoporous materials can be controlled easily through adjusting the ratio of water to cosolvent. As the molar ratio of water to ethanol changes from 0.02 to 0.73, the pore size of the calcined materials can be enlarged from 32 to 94Å, attributing to the aggregation behavior of the multiarm hyperbranched polymer in different systems. Moreover, the pore size of the obtained mesoporous silica can be also adjusted by selecting different kinds of cosolvent. The polarity and solubility of cosolvents are believed to be two important factors in affecting the pore size. Thus, a facile and efficient method for controlling the pore size of mesoporous silica has been developed by using hyperbranched polymers as templates. [Copyright &y& Elsevier]

Abstract: This work reported for the first time the surface functionalization of titanate nanotubes (TNTs) with biodegradable poly(ɛ-caprolactone) (PCL). A “grafting from” approach based on in situ ring-opening polymerization of ɛ-caprolactone from TNTs with a special surface modification was adopted to prepare the PCL-g-TNTs. The thickness of the grafted PCL shell can be controlled by increasing reaction time. After grafted with PCL, both the dissolubility and flexibility of the tubes were greatly improved. The obtained PCL-g-TNTs can easily disperse in several organic solvents, and the dispersal stability depends on solvent polarity and PCL shell thickness. Furthermore, the PCL immobilized on the surface of TNTs still possessed a good biodegradable capacity and could be completely decomposed in the presence of Pseudomonas (PS) lipase. The PCL-g-TNTs reported here are promising in biotechnology applications due to good dissolubility, flexibility, biocompatibility and the tubular nano-structure. [Copyright &y& Elsevier]

• A direct and reliable method to study the gas–liquid interface was introduced. • A positive adsorption of DDA was directly observed and confirmed by ToF-SIMS. • Adsorption structure of DDA at interface was studied by ToF-SIMS and MD simulation. • Primary factors affecting foam stability of DDA were proposed. Dodecylamine (DDA) as a collector was widely applied in flotation, but its high foam stability has also been proven in many laboratories or beneficiation plants. In this work, the adsorption configuration of DDA at the gas–liquid interface and its relationship with foam stability at different pH and concentration levels was investigated to gain insights into the performance and stability mechanism of DDA. A direct, reliable, and new way to investigate the gas–liquid interface information was introduced. Froth stability experiments, surface tension measurements, time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements assisted by principal component analysis (PCA), and molecular dynamics (MD) simulation were carried out. Results revealed that the foam stability of DDA was extremely high under strong acidic condition. It increased gradually and then decreased as the DDA concentration increased, and reached the maximum at the critical micelle concentration. The positive adsorption of DDA was directly observed and confirmed by ToF-SIMS. The primary factor affecting the foam stability of DDA at different pH levels was not the adsorption capacity of DDA at the gas–liquid interface (surface tension) but the interaction intensity between the head groups of DDA and water molecules. The dominant factors affecting the foam stability of DDA at different concentrations were the adsorption capacity of DDA at the gas–liquid interface (surface tension), the interaction intensity between the head groups and water molecules, and the arrangement configuration of DDA molecules at gas–liquid interface. [ABSTRACT FROM AUTHOR]

• Surface coverage thickness of Ca2+ on quartz increased as pH increased. • The coverage density of sodium oleate on quartz at different pH levels varied. • ToF-SIMS and AFM studies supported the importance of the thickness and density of Ca2+ coverage. • Quartz was activated by Ca2+, forming C 18 H 33 O 2 Ca on the surface. • Preparation methods of AFM samples without a complete cleavage plane were introduced. In this work, the activation mechanism of calcium species on the α-quartz surface was investigated. Microflotation, zeta potential measurements, first-principle calculation based on density functional theory (DFT), time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements and atomic force microscope (AFM) were conducted in this investigation. Sample preparation methods for minerals without a complete cleavage plane and reagent adsorption determination were introduced. Results revealed that quartz could be activated by calcium ions at the pH above 10, and calcium ion concentrations at pH below 10 slightly affected quartz recovery. Ca2+ could repel the hydration shell and hydroxylation on the quartz and be preferentially adsorbed onto the quartz surface at an alkaline pH. However, the coverage thickness and density of Ca2+ and the relevant coverage density of sodium oleate increased as the pH increased. The adsorbed amounts in the horizontal and vertical directions were also not uniform. The surface coverage thickness and density of Ca2+ and the corresponding amount of adsorbed sodium oleate played an important role in the activation of quartz. When the pH was above 10, the thickness and density of Ca2+ coverage on the quartz surface was sufficient, and Ca2+ could subsequently react with sodium oleate forming C 18 H 33 O 2 Ca. Thus, the quartz hydrophobicity was improved. [ABSTRACT FROM AUTHOR]