Alternative approaches complementing the existing technologies for analysis of nucleic acids and their assemblies are necessary to take on the new challenges posed by the postgenomic era. The ...versatility of MS in biopolymer analysis and its ability to reach beyond sequence information are the basis of ever expanding applications aimed at the elucidation of nucleic acid structure-function relationships. This Feature summarizes the current state of MS-based approaches devised to overcome the limitations of traditional techniques and to advance different facets of nucleic acids research.
The combination of magnetic hyperthermia therapy with the controlled release of chemotherapeutic agents in tumors may be an efficient therapeutic with few side effects because the bioavailability, ...tolerance and amount of the drug can be optimized. Here, we prepared magnetoliposomes consisting of magnetite nanoparticle cores and the anticancer drug gemcitabine encapsulated by a phospholipid bilayer. The potential of these magnetoliposomes for controlled drug release and cancer treatment via hyperthermic behavior was investigated. The magnetic nanoparticle encapsulation efficiency was dependent on the initial amount of magnetite nanoparticles present at the encapsulation stage; the best formulation was 66%. We chose this formulation to characterize the physicochemical properties of the magnetoliposomes and to encapsulate gemcitabine. The mean particle size and distribution were determined by dynamic light scattering (DLS), and the zeta potential was measured. The magnetoliposome formulations all had acceptable characteristics for systemic administration, with a mean size of approximately 150 nm and a polydispersity index <0.2. The magnetoliposomes were stable in aqueous suspension for at least one week, as determined by DLS. Temperature increases due to the dissipation energy of magnetoliposome suspensions subjected to an applied alternating magnetic field (AMF) were measured at different magnetic field intensities, and the values were appropriated for cancer treatments. The drug release profile at 37 °C showed that 17% of the gemcitabine was released after 72 h. Drug release from magnetoliposomes exposed to an AMF for 5 min reached 70%.
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•It is possible to add WFA together with pozzolan to obtain a ternary cement.•The addition of WFA decreases the compressive strength of the mortar.•HWA decreases the elastic modulus ...and workability of the concrete.•The HWA presents reactive behavior in the alkali-aggregate reaction (AAR) test.
The compressive strength behavior of cement mixtures produced with wood ash was investigated. This ash was characterized to determine its potential as supplementary cementitious materials (SCMs) in Portland Cement (PC) as pozzolanic material (WFA) and as active aggregate (HWA). By assuming the pozzolanic mineral addition content in Portland Cement PC IV as reference, as well as considering WFA with the highest pozzolanic potential, we developed the SCM binder fraction. This was achieved by replacing up to 50 wt% of PC, combining WFA and pozzolan with Portland Cement PC V. By defining the binder fraction along with HWA characterization, concrete compositions replacing up to 30 vol% of the aggregate fraction with HWA were established. The use of WFA reduces the compressive strength, while HWA decreases the elasticity modulus of the produced concretes. Ecoconcrete containing ~17.2 wt% of waste exhibited over 40 MPa after 28 days of curing and high durability.
•Fabrication of waveguides in Transparent Glass-Ceramic (TGC) via fs-laser writing.•Buried waveguides in Magnesium Aluminum Silicate (MAS) TGC and its precursor glass.•Single mode (precursor glass) ...and ring mode (MAS-TGC) were obtained.•Femtosecond laser writing technique.•Strengthened photonic devices.
Transparent glass-ceramics (TGC) have been investigated to replace hard, mechanically strong, scratch resistant materials in ballistic armor applications and smart phone displays. Certain types of TGC have superior performance than borosilicate and soda-lime glasses, and are much easier to produce, especially large parts, than transparent mono or polycrystalline ceramics. Thereupon, transparent glass-ceramics could be feasible in other applications, such as stronger photonic devices. In this work, we used femtosecond laser pulses to inscribe optical waveguides inside a magnesium aluminum silicate (MAS) precursor glass and glass-ceramic, which has shown satisfactory mechanical properties to be applied as ballistic armor. Single mode waveguides for the precursor glass and ring mode for MAS-TGC were obtained and characterized (total insertion loss, mode profile, and threshold energy for heat diffusion at different fabrication depths). Micro-Raman measurements on the microfabricated waveguide core and on the pristine material surface show some difference for the TGC, but none for the glass. Particularly, we found that the threshold energy for heat diffusion is higher in the MAS glass-ceramic than in its parent glass. Its good optical waveguiding and mechanical properties indicate that this new TGC might be adequate for photonic devices that require mechanically competent materials.
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► Reuse of industrial steel waste as a catalyst for wastewater treatment. ► Use of a low-cost catalyst as an iron source for photo-Fenton-like processes. ► High activity of steel ...waste for the decolorization of RR195 by AOPs. ► Evidence of homogeneous and heterogeneous photo-Fenton reactions with steel waste as the catalyst.
This study investigated the use of blast furnace dust (BFD) as a catalyst to degrade an azo dye (RR195) by photo-Fenton-like processes. This waste contains hematite, magnetite and maghemite as iron sources, and its dissolution provides more Fe3+ than Fe2+ for the Fenton reaction in solution. The effect of hydrogen peroxide concentration and catalyst dosage on the kinetics of hydrogen peroxide decomposition and dye decolorization was also studied. The photo-Fenton-like process was compared to Fenton-like (using BDF without irradiation), Fenton and photo-Fenton (using FeSO4 as iron source), UV/H2O2 and UV processes. The results indicated that BFD can be effectively used as a catalyst in the photocatalytic process because it was able to completely degrade H2O2 via an adjusted Langmuir–Hinshelwood model. Although the photo-Fenton-like reaction with BFD showed the same decolorization efficiency of RR195 as the homogeneous photo-Fenton process (using FeSO4), the catalyst considerably increased the reaction rates (more than five times) according pseudo-first-order kinetics. The results of the irradiated systems using BFD can be more efficient in dye decolorization due to greater hydroxyl radical production through Fe2+/Fe3+ cycling and by the occurrence of homogeneous and heterogeneous reactions. The practical use of the steel waste is promising, because it increases the reaction rates and its high density and magnetic proprieties enable an easy solid–liquid separation and reuse, making it a versatile material for environmental applications.
Samples of ferrofluids containing chemically stabilized nanoparticles of magnetite (Fe3O4) with tetramethylammonium hydroxide (TMAOH) were prepared by a direct reduction–precipitation method. The ...influences of aging time and temperature on the size and monodispersion characteristics of the produced nanoparticles were investigated. Transmission electron microscopy, powder X-ray diffraction, Fourier-transform infrared, and magnetization measurements with applied magnetic field up to 2T were used to characterize the synthesized iron oxides. Raising the temperature of the synthesized material in autoclave affects positively the monodispersion of the nanoparticles, but it was not found to significantly influence the size itself of individual particles.
► From report protocols, chemical synthesis of magnetite with FeCl3 (stable in air) instead of FeCl2 or Fe(NO3)3, precursor. ► Chemical reduction with Na2SO3 provides an additional advantage. ► As any eventual reformation of Fe3+ from reoxidization of produced Fe2+ may be sequestered by remaining SO32− in the medium. ► Nanoparticles are stably individualized with tetramethylammonium hydroxide that acts as a surface-active agent. ► Thermal treatment reduces further the mean sizes of particles, as required for many medical uses.
In this work the adsorption features of activated carbon and the magnetic properties of iron oxides were combined in a composite to produce magnetic adsorbents. These magnetic particles can be used ...as adsorbent for a wide range of contaminants in water and can subsequently be removed from the medium by a simple magnetic procedure. Activated carbon/iron oxide magnetic composites were prepared with weight ratios of 2:1, 1.5:1 and 1:1 and characterized by powder XRD, TG, magnetization measurements, chemical analyses, TPR, N
2 adsorption–desorption isotherms, Mössbauer spectroscopy and SEM. The results suggest that the main magnetic phase present is maghemite (γ-Fe
2O
3) with small amounts of magnetite (Fe
3O
4). Magnetization enhancement can be produced by treatment with H
2 at 600 °C to reduce maghemite to magnetite. N
2 adsorption measurements showed that the presence of iron oxides did not significantly affect the surface area or the pore structure of the activated carbon. The adsorption isotherms of volatile organic compounds such as chloroform, phenol, chlorobenzene and drimaren red dye from aqueous solution onto the composites also showed that the presence of iron oxide did not affect the adsorption capacity of the activated carbon.
This communication describes a general approach for site-specific fluorescence labelling of RNA using a cytidine triphosphate (CTP) analogue derivatized with a trans-cyclooctene group. The analogue ...was efficiently incorporated into a model RNA strand using in vitro transcription. Bio-orthogonal reaction with fluorescein-labelled tetrazine was utilized to fluorescently tag the synthetic RNA strand.
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