Heterogeneous catalysis for the synthesis of carbon dots (CDs) from biomass source

It has been evaluated the capacity of several phosphate-based acid catalysts of transition metals such as vanadium and niobium in the synthesis of carbon dots (CDs) via a hydrothermal process. For this purpose, two sources of carbohydrates have been used: commercial xylose and liqueur of xylose obtained from the treatment of olive pits. Catalysts were characterized by means of NH3-TPD, DTA/TG, XRD and XPS. The reaction was carried out at 180 °C and reaction time was varied between 2 and 4h. The properties and characteristics of CDs nanoparticles were analysed confirming the existence of such nanoparticles irrespective the carbohydrate source. In terms of CDs quality, both syntheses produced comparable results. At the same time, N doped CDs with enhanced fluorescence were also synthesized following a kindred hydrothermal process and the photocatalytic activity was studied. With the aim of evaluating the environmental impact of the synthesis from commercial xylose versus the synthesis from biomass, a Life Cycle Assessment (LCA) analysis was carried out for both syntheses. It showed that the most sustainable synthesis route is the one that uses commercial xylose as carbonaceous feedstock. Furthermore, while electricity is the main contributor to all impact categories in both synthesis routes, the main differences that determine their relative sustainability are associated with the identity of the carbon precursor.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Reduced Fluoresceinamine as a Fluorescent Sensor for Nitric Oxide

A new fluorescent sensor for nitric oxide (NO) is presented that is based on its reaction with a non fluorescent substance, reduced fluoresceinamine, producing the highly fluorescent fluoresceinamine. Using a portable homemade stabilized light source consisting of 450 nm LED and fiber optics to guide the light, the sensor responds linearly within seconds in the NO concentration range between about 10–750 μM with a limit of detection (LOD) of about 1 μM. The system generated precise intensity readings, with a relative standard deviation of less than 1%. The suitability of the sensor was assessed by monitoring the NO generated by either the nitrous acid decomposition reaction or from a NO-releasing compound. Using relatively high incubation times, the sensor also responds quantitatively to hydrogen peroxide and potassium superoxide, however, using transient signal measurements results in no interfering species

Zero Energy of Plane-Waves for ELKOs

We consider the ELKO field in interaction through contorsion with its own spin density, and we investigate the form of the consequent autointeractions; to do so we take into account the high-density limit and find plane wave solutions: such plane waves give rise to contorsional autointeractions for which the Ricci metric curvature vanishes and therefore the energy density is equal to zero identically. Consequences are discussed.Comment: 7 page

Factorial analysis of the trihalomethanes formation in water disinfection using chlorine

The factors that affect trihalomethane (THM) (chloroform, bromodichloromethane, chlorodibromomethane and bromoform) formation from the chlorination of aqueous solutions of hydrophobic fulvic acids (FA) were investigated in a prototype laboratorial simulation using factorial analysis. This strategy involved a fractional factorial design (16 plus 5 center experiments) of five factors (fulvic acids concentration, chlorine dose, temperature, pH and bromide concentration) and a Box Behnken design (12 plus 3 center experiments) for the detailed analysis of three factors (FA concentration, chlorine dose and temperature). The concentration ofTHMwas determined by headspace analysis by GC–ECD. The most significant factors that affect the four THM productions were the following: chloroform—FA concentration and temperature; bromodichloromethane—FA concentration and chlorine dose; chlorodibromomethane—chlorine dose; and, bromoform—chlorine dose and bromide concentration. Moreover, linear models were obtained for the four THM concentrations in the disinfection solution as function of the FA concentration, chlorine dose and temperature, and it was observed that the complexity of the models (number of significant factors and interactions) increased with increasing bromine atoms in the THM. Also, this study shows that reducing the FA concentration the relative amount of bromated THM increases

Periods Of Weed Interference In Maize Crops Cultivated In The First And Second Cycles

The interference of weeds in maize production may be reflected in grain yield losses that vary as a function of the density, stage and degree of aggressiveness of the species present. In the agricultural ecosystem, crops and weeds demand light, water, nutrients and space, which are frequently not available in sufficient quantities, leading to competition. The aim of this work was to determine the period of interference of weed plants, in particular of naked crabgrass (Digitaria nuda) on maize crop in the first and second harvest. The treatments were defined as increasing periods of coexistence and increasing control of weed community (7, 14, 21, 28, 35, 42, 49, and 56 days), two more controls, a control including one with weed control until the end of the culture cycle and another with coexistence until the harvest. For each period, were evaluated the stand of maize plants, length of ear, number of grains per row, number of rows per ear, cob, 100-grain weight, and grain productivity. The data obtained were subjected to analysis of variance using the F test, with average treatments compared using Tukey's test at 5% probability. Crop productivity was evaluated by means of regressions, the critical periods of interference were estimated. The critical timing of weed removal was 25 days for both harvests. The critical weed free period was 54 and 27 days for the first and second harvest respectively. For the conditions of the first and second harvest, the critical period of weed control was of 29 and 2 days respectively.3752867287

Multivariate analysis of the water quality variation in the Serra da Estrela (Portugal) Natural Park as a consequence of road deicing with salt.

The concentration of some anions (Cl, F, NO3, and SO4), cations (Na, K, Ca, and Mg), pH and conductivity was determined in seven sampling points in the Serra da Estrela Mountains (Portugal) to verify if the application of road deicing with salt provokes impact in the water quality. Multivariate chemometric data analysis techniques of clustering and factor analysis were used. Preliminary analysis shows an overall conductivity increase in late spring and a decrease in late summer. A strong association between sodium chloride and the conductivity was observed by cluster analysis. Factor analysis supports the previous results and shows that the variation of the concentration of sodium chloride is the main source of the variance of the data along the year. In conclusion, the spreading of salt during the winter creates a local and seasonal impact on the water quality

Combining photodynamic therapy with immunostimulatory nanoparticles elicits effective anti-tumor immune responses in preclinical murine models

Photodynamic therapy (PDT) has shown encouraging but limited clinical efficacy when used as a standalone treatment against solid tumors. Conversely, a limitation for immunotherapeutic efficacy is related to the immunosuppressive state observed in large, advanced tumors. In the present study, we employ a strategy, in which we use a combination of PDT and immunostimulatory nanoparticles (NPs), consisting of poly(lactic-co-glycolic) acid (PLGA)-polyethylene glycol (PEG) particles, loaded with the Toll-like receptor 3 (TLR3) agonist poly(I:C), the TLR7/8 agonist R848, the lymphocyte-attracting chemokine, and macrophage inflammatory protein 3 alpha (MIP3 alpha). The combination provoked strong anti-tumor responses, including an abscopal effects, in three clinically relevant murine models of cancer: MC38 (colorectal), CT26 (colorectal), and TC-1 (human papillomavirus 16-induced). We show that the local and distal anti-tumor effects depended on the presence of CD8(+) T cells. The combination elicited tumor-specific oncoviral- or neoepitope-directed CD8(+) T cells immune responses against the respective tumors, providing evidence that PDT can be used as an in situ vaccination strategy against cancer (neo)epitopes. Finally, we show that the treatment alters the tumor microenvironment in tumor-bearing mice, from cold (immunosuppressed) to hot (pro-inflammatory), based on greater neutrophil infiltration and higher levels of inflammatory myeloid and CD8(+) T cells, compared to untreated mice. Together, our results provide a rationale for combining PDT with immunostimulatory NPs for the treatment of solid tumors.Imaging- and therapeutic targets in neoplastic and musculoskeletal inflammatory diseas

Geoecological evaluation of local surroundings for the purposes of recreational tourism

The paper presents geoecological evaluation of the city of Loznica for the purposes of sports and recreational tourism based on quantitative method of diversity, V-Wert Method. Using the GIS tool by the quantitative method, the criteria of natural components (relief, forest, water surface and climate) are evaluated for the analyzed area. In the proposed method, the climate factor was supplemented by the analysis of the bioclimatic index Universal Thermal Climate Index (UTCI). When the evaluation was completed, the final results were obtained based on which the degrees of convenience of different parts of the analyzed area have been presented. Out of the total analyzed surface, which amounts to 705 km2 , favorable surfaces comprise 21 km2 (2.98%), and very favorable surfaces comprise 33 km2 , i.e. 4.68% of the territory. The largest area consists of conditionally favorable terrains — 333 km2 (47.23%). Since one of the basic strategic priorities of the City of Loznica is improvement and development of sports and recreational tourism, the aim of this analysis is to emphasize the potential of the mentioned area in terms of general suitability of the terrain for the development of this type of tourism