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Copyright of Pasos: Revista de Turismo y Patrimonio Cultural is the property of Universidad de La Laguna, Instituto Universitario de Ciencias Politicas y Sociales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: The aim of this study was to evaluate the long‐term cost‐effectiveness of sacral neuromodulation in the treatment of severe faecal incontinence as compared with symptomatic management. Methods: In the public health field, a micro‐costing evaluation method was conducted from the perspectives of the health system and the society. The incremental cost‐effectiveness ratio was used as a decision index, and we considered various scenarios to evaluate the impact of the cost of symptomatic management and percutaneous nerve evaluation success rate in its calculation. Clinical data were retrieved from a consecutive cohort of 93 patients with severe faecal incontinence undergoing sacral neuromodulation after a failure of conservative (pharmacological and biofeedback) and/or surgical (sphincteroplasty) first‐line treatments were considered. Results: The long‐term incremental cost‐effectiveness ratio comparing sacral neuromodulation versus symptomatic management was 14347€/QALY and 28523€/QALY from the societal and health service provider's perspectives, respectively. If the definitive pulse generator implant success rate was 100%, incremental cost‐effectiveness would correspond to 6831€/QALY and 16761€/QALY, respectively. Conclusions: Sacral neuromodulation may be considered a cost‐effective technique in the long‐term treatment of severe faecal incontinence from the societal and health care sector perspectives. Improving patient selection and determining the predictive outcome factors for successful sacral neuromodulation in the treatment of faecal incontinence would improve cost‐effectiveness. [ABSTRACT FROM AUTHOR]

The synthesis of TiO2 nanoparticles (NPs) in supercritical media has been reported over the last two decades. However, very few studies have compared the physicochemical characteristics and photoactivity of the TiO2 powders produced from different precursors, and even fewer have investigated the effect of using different ratios of hydrolytic agent/precursor (HA/P) on the properties of the semiconductor. To bridge this knowledge gap, this research focuses on the synthesis and characterization of TiO2 NPs obtained in a supercritical CO2 medium from four different TiO2 precursors, namely diisopropoxytitanium bis (acetylacetonate) (TDB), titanium (IV) isopropoxide (TIP), titanium (IV) butoxide (TBO), and titanium (IV) 2-ethylhexyloxide (TEO). Further, the effect of various HA/P ratios (10, 20, 30, and 40 mol/mol) when using ethanol as a hydrolytic agent has also been analyzed. Results obtained have shown that the physicochemical properties of the catalysts are not significantly affected by these variables, although some differences do exist between the synthesized materials and their catalytic performances. Specifically, photocatalysts obtained from TIP and TEO at the higher HA/P ratios (HA/P = 30 and HA/P = 40) led to higher CO2 photoconversions (6.3–7 µmol·g−1·h−1, Apparent Quantum Efficiency < 0.1%), about three times higher than those attained with commercial TiO2 P-25. These results have been imputed to the fact that these catalysts exhibit appropriate values of crystal size, surface area, light absorption, and charge transfer properties. [ABSTRACT FROM AUTHOR]

The objective of this work was to analyze the effect of carbon support on the activity and selectivity of N-doped TiO2 nanoparticles. Thus, N-doped TiO2 and two types of composites, N-doped TiO2/CNT and N-doped TiO2/rGO, were prepared by a new environmentally friendly one-pot method. CNT and rGO were used as supports, triethylamine and urea as N doping agents, and titanium (IV) tetraisopropoxide and ethanol as Ti precursor and hydrolysis agent, respectively. The as-prepared photocatalysts exhibited enhanced photocatalytic performance compared to TiO2 P25 commercial catalyst during the photoreduction of CO2 with water vapor. It was imputed to the synergistic effect of N doping (reduction of semiconductor band gap energy) and carbon support (enlarging e−-h+ recombination time). The activity and selectivity of catalysts varied depending on the investigated material. Thus, whereas N-doped TiO2 nanoparticles led to a gaseous mixture, where CH4 formed the majority compared to CO, N-doped TiO2/CNT and N-doped TiO2/rGO composites almost exclusively generated CO. Regarding the activity of the catalysts, the highest production rates of CO (8 µmol/gTiO2/h) and CH4 (4 µmol/gTiO2/h) were achieved with composite N1/TiO2/rGO and N1/TiO2 nanoparticles, respectively, where superscript represents the ratio mg N/g TiO2. These rates are four times and almost forty times higher than the CO and CH4 production rates observed with commercial TiO2 P25. [ABSTRACT FROM AUTHOR]

Objective: The identify and quantify, by high performance liquid chromatography, flavonoids from leaf and stem extracts of Acer negundo. Design/methodology/approach: Ethanolic extracts of Acer negundo were analysed with high performance liquid chromatography to quantify and identify their major antioxidant flavonoids. Results: Leaf extracts had high concentrations of rutin (34.19 µg/mL) and catechin (33.97 µg/mL), intermediate concentrations of apigenin (19.05 µg/mL), gallic acid (19.04 µg/mL), ferulic acid (17.2 µg/mL) and 2.5 dihydroxybenzoic acid (12.72 µg/mL), and low concentrations of caffeic acid (6.15 µg/mL), quercetin-3-β-glucoside (4.97 µg/mL) and isorhamnetin (4.68 µg/mL). In the stem's extracts, the highest concentrations were of ferulic acid (7.96 µg/mL), rutin (5.61 µg/mL) and catechin (4.37 µg/mL); medium concentration were identified for isorhamnetin (3.31 µg/mL) and quercetin-3-β-glucoside (2.01 µg/mL) and apigenin (0.79 µg/ mL) was identified at the low concentrations. Gallic acid, caffeic acid or 2,5-dihydroxybenzoic acid were not detected. Limitations/implications: Some flavonoids have been identified in other Acer species but have not been identified and quantified in Acer negundo, a Mexican species. Findings/conclusions: For the first time we report gentisic acid in Acer negundo leaf extracts. This analytical method can be standardized to serve as a quality analysis of maple tree products. [ABSTRACT FROM AUTHOR]

For the photocatalytic degradation of antioxidant 2,6-di-tert-butyl-hydroxytoluene (BHT), several TiO2-based composites have been prepared in MWCNT from titanium isopropoxide and ethanol via supercritical CO2 synthesis followed by calcination at 400 °C. TEM and XRD showed uniform coverage of CNT by 10 nm TiO2 particles in the anatase form, and spectral analyses revealed the formation of CNT/TiO2 structure. Further, synthesized material displayed significant visible light absorption and absorption edge shifted to longer wavelengths. Once the material was characterized, the effect of adsorption and photochemical degradation of BHT was investigated in the wavelength range from 400 to 700 nm, in batch mode, by monitoring the concentrations of BHT as a function of time. CNT/TiO2 composites were more efficient than commercial TiO2 P25 in the photodegradation of the antioxidant. In particular, CNT50/TiO250, a composite with 50% by weight of CNT, was the best catalyst, stable, and completely degrading BHT within 30 min of exposure to visible light. The role played by different reactive oxidative species (h+, OH·, 1O2, and O 2 ∙ − ) in the photocatalytic reaction was also studied by using appropriate radical scavengers that inhibited the corresponding active species. Superoxide radical was found the main oxidizing agent. [ABSTRACT FROM AUTHOR]

Copyright of Revista Medica del IMSS is the property of Direccion de Prestaciones Medicas - IMSS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: BACKGROUND: In previous studies the enhanced activity of TiO2‐based catalysts synthesized in supercritical medium for photocatalytic reduction of CO2 was proved. RESULTS: In this study, Cu/TiO2 photocatalysts were synthesized by hydrothermal methods in supercritical CO2. Two titanium precursors [titanium tetraisopropoxide and diisopropoxititanium bis(acetylacetonate)], two alcohols (ethanol and isopropyl alcohol), and one metal precursor (Cu (II) acetylacetonate) were used in the synthesis. Catalysts produced showed improved properties in comparison with the commercial reference catalyst (Degussa P‐25, Evonik). CONCLUSIONS: Specifically, it has been found that Cu/TiO2 catalysts may yield methane production rates 20 times larger than that of commercial TiO2 catalyst without diminishing CO production rate (about 5 times higher than that of commercial catalyst). This result has been mainly imputed to both the formation of oxygen vacancies during the synthesis in supercritical medium and the high capacity of copper to adsorb and activate CO2 molecules, while preventing CO molecules from reoxidation, and avoiding the competitive reaction of hydrogen formation. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Jatropha curcas has significant potential for production of biodiesel and secondary metabolites with medical applications. The effect of jasmonic acid (JA) on flavonoid production and antioxidant responses in two Mexican J. curcas plants (accessions I-64 and I-52), growing under controlled environmental conditions, was studied. Foliar application of JA (0.25, 0.5, and 1.0 mM) increased flavonoid content by 3.3-fold (445.6 ± 62.2 µg QE g DW) at 1.0 mM in the I-64 accession after 120 h. At this time, individual flavonoid levels of kaempferol, apigenin, and vitexin were 6.8 (106.8 ± 18.6 µg g DW), 4.4 (15.5 ± 1.5 µg g DW), and 8.1 (6.27 ± 1.3 µg g DW) times higher than in the controls, while for the I-52 specimens, the highest increase of flavonoids occurred at 24 h. In treated I-52 plants, enhancement of 58% (74.7 ± 9.2 µg g DW) in anthocyanins occurred after 120 h, while in I-64 plants, they remained similar to controls. Phenylalanine ammonia lyase showed a peak of activity after 120 h in treated I-64 plants, while the I-52 accession showed peaks at 24 and 120 h. Elicited I-64 plants presented HO levels similar to controls with a 30.6% increase in catalase (CAT) and 3.3-fold in ascorbate peroxidase (APX) activities. In elicited I-52 plants, a 2.4-fold increase in HO concentration was related to a 65.6% decrease of CAT and a 1.8-fold increase of APX activities. Therefore, under JA elicitation, J. curcas plants increased antioxidant responses including flavonoid and anthocyanin production to maintain cell redox balance. [ABSTRACT FROM AUTHOR]

BACKGROUND Titanium dioxide is the photocatalyst par excellence in environmental applications. Nevertheless, over the years various methods aiming to improve its efficiency have been presented. Herein, we report that TiO2 synthesis in supercritical medium can result in a significant enhancement in the rate of CO2 photocatalytic conversion. RESULTS Specifically, catalysts obtained from two titanium precursors (titanium tetraisopropoxide and diisopropoxititanium bis(acetylacetonate)) and two alcohols (ethanol and isopropyl alcohol) by hydrothermal synthesis in supercritical CO2 are shown to exhibit improved properties in comparison with the standard reference catalyst (Degussa P-25, Evonik). CONCLUSION In particular, upgraded characteristics are related to reactants adsorption (higher specific surface areas, presence of surface hydroxyl groups), light absorption and excitation (better absorbance in visible range, lower band gap energy), and charge separation (appropriate morphology and crystallinity). Furthermore, when these catalysts are tested in the photocatalytic reduction of CO2, CO and CH4 production rates 3- and 15.7-fold higher than those corresponding to the commercial catalyst have been found. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Jatropha curcas has considerable potential for production of biodiesel and secondary metabolites with medicinal uses. Herein, J. curcas cell suspension cultures were established to study the effect of jasmonic acid (JA) elicitation on triterpene production and oxidative responses. Cell cultures grown in dark conditions reached maximum biomass accumulation at the 12th day of culture (14.3 ± 0.45 g DW L) with a specific growth rate μ = 0.131 d. Elicitation with JA (200 or 400 μM) on 4-days-old cell cultures caused reduction in biomass and triterpene contents. In contrast, application of 200 μM JA at the 7th day of culture triggered triterpene accumulation by three times (1180 ± 12.3 μg g DW, at day 2) with respect to control, without significant changes in biomass and viability. After 2 days of elicitation, betulin increased up to 7.3-fold (from 110.6 ± 20.7 to 808.7 ± 55.4 μg g DW), while betulinic acid reached the maximum amount at day 6 after elicitation (245.6 ± 3.7 to 835 ± 41.5 μg g DW). Lupeol presented a moderate increase (167.9 ± 51.0-288.8 ± 7.3 μg g DW) along 8 days after elicitation. In correlation with triterpene production, JA application induced oxidative responses evaluated by an increase in the HO levels up to three times and of malondialdehyde by 59 %. At day 4 after elicitation, catalase showed higher increase (122 %) than peroxidases (63 %) and ascorbate peroxidase (26 %). Incorporation of radioactive labels from ( R, S)-[2-C]mevalonic acid in triterpenes and sterols confirmed its role as metabolic precursor. [ABSTRACT FROM AUTHOR]

This research provides solubility data required for environmental applications involving the extraction of heavy hydrocarbons with compressed gases. Dibenzothiophene (DBT), 2-nitrophenyl disulfide (NPDS), and tetramethylthiuram disulfide (TTDS) have been selected as model compounds for this type of pollutants and isobutane as compressed gas. The solubilities obtained at 367-413 K and 3.9-7.5 MPa, expressed as solute mole fractions, were in the ranges 0.025- 0.106 for DBT, 1.2 ? 10-4-6.3 ? 10-4 for NPDS, and between 2.7 ? 10-4 and 1.8 ? 10-3 for TTDS. They were compared to other pollutants solubilities (anthracene and carbazole). From the comparison, the following solubility order was established: DBT>anthracene>carbazole>TTDS>NPDS. Furthermore, when comparing these isobutane solubilities to those in propane and CO2, they were found to be about one and two magnitude orders larger, respectively. Results obtained were explained considering solvent density, solute vapor pressure, and interactions between solutes and solvent. Peng-Robinson equation was used to correlate the data and a good fitting attained. [ABSTRACT FROM AUTHOR]

Microbial polymers have diverse chemical structures, which determine their functional properties. Many microbial sources produce either intracellular or extracellular biopolymers. For example, Azotobacter vinelandii is a non-pathogenic soil bacterium that produces alginate, an extracellular polysaccharide. Alginates are used mainly in the food and pharmaceutical industries as stabilizing, thickening, gel- or film-forming agents. Due to its characteristics of biocompatibility, biodegradability and non-antigenicity, new applications for alginate are being discovered, such as biomaterial in the biomedical field and tissue engineering. It is well established that alginate is first synthesized as a polymannuronate from its cytosolic precursor. However, the mechanisms involved in the polymerization, modification (acetylation, epimerization and depolymerization) and translocation of alginate have been poorly elucidated. Two of the most important parameters in alginate production by A. vinelandii are dissolved oxygen tension ( DOT) and the oxygen supply conditions, as these impact both the polymer concentration and its composition, particularly its molecular weight ( MW). Several studies have revealed that increased alginate molecular weight occurs in oxygen limited conditions, specifically at oxygen concentrations near zero. This article reviews recent studies examining the influence of oxygen, under limitation (microaerophilic) and non-limitation conditions (measured as DOT and oxygen transfer rate, OTR), on the polymerization and degradation of alginate produced by A. vinelandii. This review also provides evidence for understanding these processes at the cellular level and the effect of oxygen on alginate biosynthesis. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Alginates are polysaccharides used as food additives and encapsulation agents in biotechnology, and their functional properties depend on its molecular weight. In this study, different steady-states in continuous cultures of A. vinelandii were established to determine the effect of the dilution rate (D) and the agitation rate on alginate production and expression of genes involved in alginate polymerization and depolymerization. Both, the agitation and dilution rates, determined the partitioning of the carbon utilization from sucrose into alginate and CO2 under oxygen-limiting conditions. A low D (0.07 h−1) and 500 rpm resulted in the highest carbon utilization into alginate (25%). Quantitative real-time polymerase chain reaction was used to determine the transcription level of six genes involved in alginate polymerization and depolymerization. In chemostat cultures at 0.07 h−1, the gene expression was affected by changes in the agitation rate. By increasing the agitation rate from 400 to 600 rpm, the algE7 gene expression decreased tenfold, whereas alyA1, algL and alyA2 gene expression increased between 1.5 and 2.8 times under similar conditions evaluated. Chemostat at 0.07 h−1 showed a highest alginate molecular weight (580 kDa) at 500 rpm whereas similar molecular weights (480 kDa) were obtained at 400 and 600 rpm. The highest molecular weight was not explained by changes in the expression of alg8 and alg44 (genes involved in alginate polymerization). Nonetheless, a different expression pattern observed for lyases could explain the highest alginate molecular weight obtained. Overall, the results suggest that the control of alginate molecular weight in A. vinelandii cells growing in continuous mode is determined by a balance between the gene expression of intracellular and extracellular lyases in response to oxygen availability. These findings better our understanding of the biosynthesis of bacterial alginate and help us progress toward obtain tailor-made alginates. [ABSTRACT FROM AUTHOR]

The oxygen transfer rate (OTR) was evaluated as a scale-up criterion for alginate production in 3- and 14-L stirred fermentors. Batch cultures were performed at different agitation rates (200, 300, and 600 rpm) and airflow rates (0.25, 0.5, and 1 vvm), resulting in different maximum OTR levels (OTR). Although the two reactors had a similar OTR (19 mmol L h) and produced the same alginate concentration (3.8 g L), during the cell growth period the maximum molecular weight of the alginate was 1,250 kDa in the 3-L stirred fermentor and 590 kDa in 14-L stirred fermentor. The results showed for the first time the evolution of the molecular weight of alginate and OTR profiles for two different scales of stirred fermentors. There was a different maximum specific oxygen uptake rate between the two fermenters, reaching 8.3 mmol g h in 3-L bioreactor and 10.6 mmol g h in 14-L bioreactor, which could explain the different molecular weights observed. These findings open the possibility of using $$ q_{{{\text{O}}_{ 2} }} $$ instead of OTR as a scaling criterion to produce polymers with similar molecular weights during fermentation. [ABSTRACT FROM AUTHOR]

The aim of this work has been to study the influence of small changes in the pH of kaolin suspensions on the efficiency of batch coagulation with aluminum reagents. To do that, the efficiencies obtained in the removal of kaolin from suspensions have been interpreted taking into account the values of the concentration of aluminum dosed, pH and z-potential. From the results obtained, it seems clear that the raw pH conditions of the wastewater are important to explain the results of batch coagulation processes because they influence on the speciation and coagulation mechanisms, and thus on the efficiency of the coagulation process. In the particular case studied, the small differences in the initial pH are enough to explain a change in the primary mechanisms from a very cost-effective precipitation-charge-neutralization to a less efficient floc-enmeshment mechanism. Thus, a change of 1 unit of pH in the raw wastewater is enough to decrease the dose of aluminum necessary to obtain similar removal efficiencies (around 85%) from 12 to 2 mg Al dm-3. Hence a good knowledge of the system could allow optimizing the performance of operation processes, accepting small doses of reagents in a more robust neutralization charge based process. [ABSTRACT FROM AUTHOR]

In this investigation we studied the trypanocidal activity of the ethyl esters of N-propyl (Et-NPOX) and N-isopropyl (Et-NIPOX) oxamates on bloodstream trypomastigotes and on the clinically relevant intracellular amastigotes of Trypanosoma cruzi acute infected mice. In the infected and treated mice, the levels of parasitemia were drastically reduced between days 15 and 20 of treatment and almost to zero between days 35 and 40. We also found that Et-NPOX completely eliminated amastigote nests in the myocardium of mice infected with INC-5 or NINOA T. cruzi strain, and in skeletal muscle the reduction in the number of amastigote nests was between 60 and 80% in both strains. Also, Et-NIPOX reduced by 60–80% the number of amastigote nests in the myocardium and skeletal muscle of mice infected with these T. cruzi strains. In contrast, nifurtimox, used for comparison, produced a reduction of amastigote nests of only 20–40% in the studied tissues in both strains. [ABSTRACT FROM AUTHOR]

The objective of this work was to explore Neurofeedback (NFB) effects on EEG current sources in Learning Disabled (LD) children, and to corroborate its beneficial consequences on behavioral and cognitive performance. NFB was given in twenty 30-min sessions to 11 LD children to reduce their abnormally high theta/alpha ratios (Experimental Group). Another five LD children with the same characteristics received a placebo treatment (Control Group). In the Control Group no changes in behavior or EEG current source were observed. In the Experimental Group, immediately after treatment children showed behavioral and cognitive improvements, but current source analysis showed few modifications; however, 2 months after treatment many changes occurred: a decrease in current of frequencies within the theta band, mainly in left frontal and cingulate regions, and enhancement in current of frequencies within the alpha band, principally in the right temporal lobe and right frontal regions, and of frequencies within the beta band, mainly in left temporal, right frontal and cingulate cortex regions. In conclusion, NFB is a possibly efficacious treatment for LD children with an abnormally high theta/alpha ratio in any lead. The changes observed in EEG current sources may reflect the neurophysiological bases of the improvement that children experienced in their behavioral and cognitive activities. [ABSTRACT FROM AUTHOR]

The goal of this work has been to compare for both, continuous and batch processes, the efficiencies of the chemical and the electrochemical coagulation processes with hydrolyzing aluminum salts, and to determine the similarities or differences that exist between both coagulation processes. To meet the objective, experiments of both coagulation technologies have been carried out in the same operation conditions and the results have been interpreted in terms of the mechanisms previously proposed in literature for kaolin coagulation. The charge neutralization by the adsorption of monomeric hydroxocations onto the kaolin surface can be the primary coagulation-mechanism for low concentration of aluminum and acidic pHs (below 4). In the range of pH 4-7, two primary mechanisms can explain the experimental behavior of the system: sweep flocculation for high concentration of aluminum, and a combination of precipitation-charge-neutralization and charge neutralization by adsorption of monomeric or polymeric aluminum, for low concentration of aluminum. In the continuously-operated processes, the efficiency in the turbidity-removal seems to be much related to the aluminum species present in the treated waste, and not to the way of adding aluminum to the reaction system. For the same steady-state pH and aluminum concentration, the same turbidity removal is obtained in both, the chemical and the electrochemical coagulation processes. For high aluminum/kaolin ratios, kaolin suspensions which contain sulfate as electrolyte, achieve better removals of turbidity than those containing chloride ions. The operation mode (continuous or discontinuous) influences greatly on the efficiency of the electrocoagulation processes. Similar efficiencies are obtained for low (below 5 mg dm-3) and high doses of aluminum (above 20 mg dm-3). However, at intermediate doses a strong difference is observed, with a more marked decrease in the efficiency in the discontinuous process. This observation has been explained considering that the addition of aluminum in the continuous process is instantaneous (and not progressive as in the discontinuous one), and thus, the sweep coagulation mechanism is more favored in this operation mode. [ABSTRACT FROM AUTHOR]

The trypanocidal activity of N-allyl (NAOx) and N-propyl (NPOx) oxamates and that of the ethyl esters of N-allyl (Et-NAOx) and N-propyl (Et-NPOx) oxamates were tested on cultured epimastigotes (in vitro) and murine trypanosomiasis (in vivo) using five different T. cruzi strains. NAOx and NPOx did not penetrate intact epimastigotes and therefore we were not able to detect any trypanocidal effect with these oxamates. Whereas the ethyl esters (Et-NAOx and Et-NPOx), acting as prodrugs, exhibited in vitro and in vivo trypanocidal activity on the five tested T. cruzi strains. On the contrary, when Nifurtimox and Benznidazole used as reference drugs were tested, we found that only three of the five tested T. cruzi strains were affected, whereas the other two strains, Miguz and Compostela, were resistant to the in vitro and in vivo trypanocidal activity of these compounds. [ABSTRACT FROM AUTHOR]

Copyright of Clinical & Translational Oncology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)