Au-Cu/SBA(Ti) based catalysts for photocatalytic applications

Comunicación a congresoIn this work, it has been synthesized several Au and Au-Cu alloy photocatalysts supported on two different mesoporous supports: a non-commercial SBA-15 and a post-synthesis TiO2 modified SBA-15 (TiSBA-15), with which a high dispersion of TiO2 species have been achieved maintaining the SBA-15 structure. In addition, it has also been obtained highly dispersed Au nanoparticles confined in SBA-15 pore channels, as can be observed in Figure 1. The photocatalysts have been preliminary tested in the preferential CO oxidation in a H2-rich stream (CO-PROX) at room temperature and atmospheric pressure under simulated solar light irradiation. In spite of the very low gold and copper loading (1.5 wt% and 0.5wt% respectively), the catalysts resulted active and selective in the low temperature photo-CO-PROX.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tec

Evaluación del efecto insecticida de las aguas residuales de tarwi (Lupinus mutabilis) sobre larvas de Spodoptera eridania (Lep.: Noctuidae) bajo condiciones de laboratorio

Spodoptera eridania es una plaga común en todo América. Ataca a una gran variedad de cultivos provocando pérdidas económicas. El chocho, tarwi o lupino (Lupinus mutabilis Sweet) contiene alcaloides en todo el grano que son desechados junto con el agua de extracción luego de ser removidos de manera acuosa. Esta agua residual se aprovechó para que su aplicación contra S. eridania bajo dos concentraciones (0,1 y 1 g alcaloides totales/L). Los resultados demostraron que ambas concentraciones de alcaloides no tienen un efecto significativo sobre la mortalidad de las larvas en estadio tres y cinco; sin embargo, se apreció que existe una disminución de 18% en el consumo de hoja en larvas de estadio 3

Las «coplas» celestinescas de ¿tremar?: una historia casi completa de medio pliego

Not available

Nanoestructuras de ceria-titania para fotodegradar azul de metileno con luz solar simulada

En los últimos años la protección ambiental y el uso de fuentes de energía renovables son dos objetivos principales en la investigación química. La energía solar se puede aprovechar para la degradación fotocatalítica de moléculas orgánicas contaminantes, hormonas o medicamentos, tanto en el aire, en el agua, como en las superficies, porque la luz solar es capaz de descomponerlas [1]. A pesar de la gran cantidad de aplicaciones fotocatalíticas de la titania (TiO2), fotocatalizador no tóxico, de bajo costo y muy prometedor [2], hay algunos factores críticos que limitan su fotoactividad. El principal es el valor de su salto de energía, que limita su uso como fotocatalizador en la región UV del espectro. Con el objetivo principal de extender su uso a la región visible del espectro, en literatura se ha propuesto el depósito de metales nobles en su superficie, modificaciones superficiales, así como el dopaje con iones de metales de transición o elementos de tierras raras. En este sentido, el uso de ceria (CeO2) ha atraído una gran atención debido a propiedades como su biocompatibilidad, inercia química así como su actividad en reacciones de oxidación, relacionada con la formación vacantes de oxígeno en su superficie [3]. Se ha comprobado que el sistema oxídico mixto CeO2-TiO2 es más fotoactivo que la titania pura debido a la disminución del salto de energía y a la mejora en la movilidad de los excitones. Este trabajo tiene como objetivo desarrollar fotocatalizadores basados en nanoestructuras de titania que sean activas en el visible, dopando la matriz de titania con cerio. Principalmente se pretende evaluar tanto el papel del cerio como la morfología del nanomaterial en la respuesta fotocatalítica bajo luz UV y solar.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Smart lanthanide antennas for sensing water

Two new families of lanthanide antennas are described. 8-Methoxy- 4,5-dihydrocyclopenta[de]quinolin-2(1H)-one phosphonates or carboxylates behave as selective antennas exhibiting Eu3+ luminescence in organic solvents, while quinolin-2(1H)-one analogues selectively sensitize the Tb3+ emission. These emissions are quenched by H2O addition. Based on this behaviour, the new lanthanide antennas can be used as highly sensitive water sensors.Spanish Ministerio de Economia y Competividad SAF2012-32209 FU2015-67284-RMinisterio de Ciencia e Innovacion/Agencia Estatal de Investigacion/European Regional Development Fund CTQ2017-85658-R CTQ2015-63997-C2Consejo Superior de Investigaciones Cientificas (CSIC) 201580E07

Factors affecting the performance of P22 ELISA for the diagnosis of caprine tuberculosis in milk samples

Caprine tuberculosis (TB) is a zoonosis caused by members of the Mycobacterium tuberculosis complex (MTBC). Caprine TB eradication programmes are based mainly on intradermal tuberculin tests and slaughterhouse surveillance. However, the use of serological test has been extended as a potential diagnostic tool in goats through the use of serum, plasma, or even milk samples. Milk production and the antibodies (Ab) present in milk can vary depending on several circumstances. In the present study, different factors that may affect the performance of humoral TB diagnosis were analysed using goat milk samples: 1) lactation stage, 2) a recent previous skin test (booster effect) and 3) the effect of freeze-thaw cycles on milk samples preserved with azidiol. TB-infected animals (n = 44) were selected to evaluate the evolution of the Ab levels during the 6-month lactation period, along with its potential effect on the P22 ELISA results. In general, no significant changes (p = 0.079) were observed throughout the study as regards Ab levels in milk samples between consecutive analysis although the reactivity to P22 ELISA decreased when samplings were performed at the last two months of the lactation. Regarding the booster effect, the quantitative results showed a significant variation (p < 0.001) for both milk and serum samples when serological tests were carried out 15 days after the skin test. Finally, there were no significant differences (p = 0.99) in the P22 ELISA results when using milk samples preserved with azidiol that had undergone freeze-thaw cycles.This study was funded by the Spanish Ministry of Science and Innovation through the project “Análisis del proceso de erradicación de la tuberculosis caprina a largo plazo y desarrollo de pruebas de diagnóstico y medidas de control para su mejora (GoaTBfree-UCM, reference PID2019-105155RB-C31) and the Spanish Ministry of Agriculture, Fisheries and Food. JO was supported by an FPU (Formación de Profesorado Universitario) contract-fellowship provided by the Spanish Ministerio de Ciencia, Innovación y Universidades (FPU18/05197).S

Effect of the topical administration of corticosteroids and tuberculin pre-sensitisation on the diagnosis of tuberculosis in goats

Background: Caprine tuberculosis (TB) is a zoonosis caused by members of the Mycobacterium tuberculosis complex (MTBC). Caprine TB control and eradication programmes have traditionally been based on intradermal tuberculin tests and slaughterhouse surveillance. However, this strategy has limitations in terms of sensitivity and specificity. Different factors may affect the performance of the TB diagnostic tests used in goats and, subsequently, the detection of TB-infected animals. In the present study, the effect of two of the factors that may affect the performance of the techniques used to diagnose TB in goats, the topical administration of corticosteroids and a recent pre-sensitisation with tuberculin, was analysed. Methods: The animals (n = 151) were distributed into three groups: (1) a group topically treated with corticosteroids 48 h after intradermal tuberculin tests (n = 53); (2) a group pre-sensitised with bovine and avian purified protein derivatives (PPDs) 3 days before the intradermal tuberculin test used for TB diagnosis (n = 48); and (3) a control group (n = 50). All the animals were tested using single and comparative intradermal tuberculin (SIT and CIT, respectively) tests, an interferon-gamma release assay (IGRA) and a P22 ELISA. Results: The number of SIT test reactors was significantly lower in the group treated with corticosteroids when compared to the pre-sensitised (p 0.05). No significant effect was observed on IGRA and P22 ELISA due to corticosteroids administration. Nevertheless, a previous PPD injection affected the IGRA performance in some groups. Conclusions: The application of topical corticosteroid 24 h before reading the SIT and CIT tests can reduce the increase in skin fold thickness and subsequently significantly decrease the number of positive reactors. Corticosteroids used can be detected in hair samples. A previous pre-sensitisation with bovine and avian PPDs does not lead to a significant reduction in the number of intradermal tests reactors. These results are valuable in order to improve diagnosis of caprine TB and detect fraudulent activities in the context of eradication programs.This study was funded by the “Analysis of the long-term caprine tuberculosis eradication process and development of diagnostic tests and control measures for its improvement (GoaTBfree-UCM)” Project (PID2019-105155RB-C31, Ministry of Science and Innovation of Spain) and the Ministry of Agriculture, Fisheries and Food of Spain. JO was supported by an FPU contract-fellowship (Formación de Profesorado Universitario) from the Spanish Ministerio de Ciencia, Innovación y Universidades (FPU18/05197).S

Effect of the Inoculation Site of Bovine and Avian Purified Protein Derivatives (PPDs) on the Performance of the Intradermal Tuberculin Test in Goats From Tuberculosis-Free and Infected Herds

The single and comparative intradermal tuberculin (SIT and CIT) tests are used for the ante-mortem diagnosis of caprine tuberculosis (TB). The tuberculin injection site has been associated with a different performance of the test in cattle. In contrast to that required in cattle in Europe (cervical injection), it can be carried out in the scapular region in goats. Nevertheless, there are no previous data concerning the effect of the injection site on the performance of the test in goats. The aim of the present study was to evaluate the effect of two different inoculation sites (cervical and scapular) on the performance of the SIT/CIT tests. This was done by intradermally inoculating 309 goats from two infected herds and one TB-free herd with both avian and bovine PPDs in the mid-cervical and scapular regions. None of the animals from the TB-free herd had positive reactions, and the number of reactors was not significantly higher, regardless of the inoculation site, in the high and low prevalence herds. However, significantly higher increases in skin fold thickness were observed on the cervical site when compared to the scapular site after the avian and bovine PPD inoculations in the TB-free herd (p < 0.001) and after the bovine PPD injection in the high prevalence herd (p = 0.003). The presence of clinical signs was also more evident on the cervical site when using avian and bovine PPDs in the high prevalence herd (p < 0.01). In contrast, increases in higher skin fold thickness were observed on the scapular site when compared to the cervical site after the bovine and avian PPD inoculations were employed in the low prevalence herd (p < 0.01). These results suggest that the cervical injection of PPDs may improve the sensitivity of the intradermal tuberculin test in high TB prevalence caprine herds, mainly owing to the increased presence of local clinical signs and a better performance of the CIT test. Moreover, specificity was not affected when using standard interpretations, although further analyses in a great number of herds are required in order to confirm these findings.This study was funded by the Herramientas para alcanzar la erradicación de la tuberculosis caprina (GoaTBfree) project (PID2019-105155RB-C31) and the Spanish Government's Ministerio de Agricultura, Pesca y Alimentación. JO was supported by an FPU (Formación de Profesorado Universitario) contract-fellowship provided by the Spanish Ministerio de Ciencia, Innovación y Universidades (FPU18/05197).S

Specificity of serological test for detection of tuberculosis in cattle, goats, sheep and pigs under different epidemiological situations

[EN] Background: Serum antibody detection has potential as a complementary diagnostic tool in animal tuberculosis (TB) control, particularly in multi-host systems. The objective of the present study was to assess the specificity (Sp) of an enzyme-linked immunosorbent assay (ELISA) based on the new multiprotein complex P22 for the detection of specific antibodies against the Mycobacterium tuberculosis complex (MTC) in the four most relevant domestic animals acting as MTC hosts: cattle, goat, sheep and pig. We used sera from an officially TB-free (OTF) country, Norway, and from a non-OTF one, Spain. The samples included sera from goats that had been vaccinated against M. avium subsp. paratuberculosis (MAP) and sheep from a herd in which Corynebacterium pseudotuberculosis had been isolated. Results: In cattle, the Sp ranged from 92.5 (IC95% 90.7-94) to 99.4% (IC95% 98.3-99.8) depending on the cut-off used and the origin of the samples (Spain or Norway). Sp in cattle (cut-off point 100) was significantly higher (P < 0.05) for Norwegian samples. By contrast, Sp in goats was consistently low at the 100 cut-off [30.9 (CI95%23.4-39.5)-78% (CI95% 68.9-85)]. A higher cut-off of 150 improved Sp in Norwegian goats [97% (CI95% 91.6-99)], but still yielded a poor Sp of 56.1% (CI95% 47.3-64.6) in Spanish goats. In Norway at the 100 cut-off the Sp was 58.3 (CI95% 42.2-72.9) and 90.6% (CI95% 81-95.6) in MAP vaccinated and non-vaccinated goats, respectively, indicating interference due to MAP vaccination. Sp in sheep was between 94.4 (CI95% 91.7-96.3) and 100% (CI95% 96.3-100) depending on the cut-off and country, and no diagnostic interference due to infection with C. pseudotuberculosis was recorded. Sp in pigs was 100%, regardless the cut-off point applied, and no significant differences were observed between pigs from Norway and from Spain. Conclusions: Due to its excellent Sp in pigs and acceptable Sp in cattle and sheep, this ELISA may constitute a suitable option for TB screening at herd level, particularly in OTF-countriesSIJose Antonio Infantes-Lorenzo was supported by an FPU contract-fellowship (Formación de Profesorado Universitario) from the Ministerio de Educación, Cultura y Deporte of the Spanish Government (FPU2013/6000). Alvaro Roy is the recipient of an Industrial Doctorate contract (DI-15-08110) funded by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO) and the European Social Fund. Javier Bezos is recipient of a Juan de la Cierva Incorporación research contract (IJCI-2015-24805) funded by the MINECO. This work was supported by the Spanish Ministry of Agriculture, Fisheries and Food and the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria of Spain (RTA2015–00043-C02–02). This is a contribution to Plan Nacional de I + D + i grant CGL2017–89866 WILD-DRIVER. The funding body was solely involved in funding and had no role in the design of the study, the collection, analysis, and interpretation of the data, or in writing the manuscrip

Ceria–zirconia-copper oxide catalysts for CO removal from H2-rich streams under PEMFC operating conditions

On-board hydrogen production from hydrocarbons or alcohols has been proposed as the most efficient process to obtain hydrogen for feeding proton-exchange membrane fuel cells (PEMFCs). However, the gas produced after reforming and water gas-shift processes still presents in most cases a relatively high CO concentration, that disallows efficient handling of the fuel by the Pt anode usually employed in the PEMFCs. Preferential oxidation of carbon monoxide (CO-PROX) has been recognized as one of the most straightforward and cost-effective methods to achieve acceptable CO concentrations (<10 ppm). Among different types of catalysts for the PROX reaction, those based on Ce-Zr-Cu oxides 1-3 have shown promising properties in terms of activity, selectivity and resistance to CO2 and H2O. In this work, a series of Ce–Zr–Cu mixed oxide systems, with different atomic ratios among cations, were prepared by slow co-precipitation with the aim to investigate the influence of the presence of very small amounts of zirconium on the performances of these three-component catalysts. The activity of these materials was evaluated in the CO preferential oxidation in hydrogen-rich gas stream (1.2% CO, 1.2% O2, 50% H2, He balance) in the absence and presence of CO2 and H2O, in the 40-190°C temperature range. Correlations between catalytic activity and physico-chemical properties of the materials were made by X-ray Powder Diffraction (XRPD), N2 physisorption, Temperature-Programmed Reduction (H2-TPR), X-ray Photoelectron Spectroscopy (XPS)