321 research outputs found
Aportacions a la flora de les Serres Diàniques
Hom aporta algunes dades corològiques i ecològiques per a espècies recollides al migjorn valencià, referides especialment a les comarques de la Vall d'Albaida, el Comtat i l'Alcoià; totes elles constitueixen primera o segona referència provincial.Some chorological and ecological data on species from the southern Valencian vascular flora are reported, all of them being first or second provincial citations
Análisis de las proteínas intactas Eritropoyetina y NESP mediante electroforesis capilar acoplada a la espectrometría de masas con analizador de trampa iónica
A high performance system to study the influence of temperature in on-line solid-phase extraction capillary electrophoresis
A novel high performance system to control the temperature of the microcartridge in on-line solid phase extraction capillary electrophoresis (SPE–CE) is introduced. The mini-device consists in a thermostatic bath that fits inside of the cassette of any commercial CE instrument, while its temperature is controlled from an external circuit of liquid connecting three differentwater baths. The circuits are controlled from a switchboard connected to an array of electrovalves that allow to rapidly alternate the water circulation through the mini-thermostatic-bath between temperatures from 5 to 90 ºC. The combination of the mini-device and the forced-air thermostatization system of the commercial CE instrument allows to optimize independently the temperature of the sample loading, the clean-up, the analyte elution and the electrophoretic separation steps.
The system is used to study the effect of temperature on the C18-SPE–CE analysis of the opioid peptides, Dynorphin A (Dyn A), Endomorphin1 (END) and Met-enkephalin (MET), in both standard solutions and in spiked plasma samples. Extraction recoveries demonstrated to depend, with a non-monotonous trend, on the microcartridge temperature during the sample loading and became maximum at 60 ºC. Results prove the potential of temperature control to further enhance sensitivity in SPE–CE when analytes are thermally stable.Facultad de Ciencias ExactasLaboratorio de Investigación y Desarrollo de Métodos Analíticos (LIDMA)Centro de Investigación y Desarrollo en Tecnología de Pintura
Improvement in Char Strength with an Open Cage Silsesquioxane Flame Retardant
Different characterization techniques were used to study the hydrolysis and condensation
reaction kinetics of 3-methacryloxypropyltrimethoxysilane (MAPTMS) to obtain open cage
silsesquioxane oligomers. The formation of hydrogen bonds, which condition the chemical structures
of the resulting products, was identified. Improved thermal and fire resistant behavior of unsaturated
polyester (UP) composites prepared with aluminium trihydroxide (ATH) and the synthesized
oligomer were registered. Opened silsesquioxane structures also showed an improvement in the
mechanical properties of the char formed after firin
Development of a geometrical model for the determination of the average intensity in a flow-through UV-LED reactor and validation with biodosimetry and actinometry
Ultraviolet (UV) treatment is widely used for water disinfection. The recent development and improvement of the light emitting diodes (LEDs) in the UVC range makes them an alternative to the traditional mercury vapor UV lamps in the middle or long term. Determining the UV intensity applied by a reactor is essential for evaluating its efficacy. Although doing so is relatively straightforward in simple laboratory reactors, such as a collimated beam reactor (CBR), its calculation for more complex devices, such as a flow-through reactor (FTR), requires indirect approaches. The objective in this study is determining the UV intensity in FTRs equipped with UV-C LEDs by utilizing indirect approaches such as the geometrical modeling of the intensity distribution, chemical actinom-etry, and biodosimetry using a CBR as a reference. With this method, the inactivation of four bacterial indicators in both the CBR and FTR have also been addressed. The three approaches that were used reported similar values of mean intensity with an average value of 0.86 mW cm-2. Determining the mean intensity enabled calculating the UV doses that were applied to the target water and then determining the inactivation kinetics parameters. The UV dose that was necessary to achieve four-log reductions from the initial bacterial concentration ranged from 5.8 to 17.5 mJ cm-2 depending on the target species. Additionally, the geometrical model developed in this study introduces new possibilities into the optimization of the reactor design
On the Efficacy of H2O2 or S2O82- at Promoting the Inactivation of a Consortium of Cyanobacteria and Bacteria in Algae-Laden Water
Harmful algal blooms in coastal areas can significantly impact a water source. Microorganisms such as cyanobacteria and associated pathogenic bacteria may endanger an ecosystem and human health by causing significant eco-hazards. This study assesses the efficacy of two different reagents, H2O2 and S2O82-, as (pre-)treatment options for algae-laden waters. Anabaena sp. and Vibrio alginolyticus have been selected as target microorganisms. With the objective of activating H2O2 or S2O82-, additional experiments have been performed with the presence of small amounts of iron (18 mu mol/L). For the cyanobacterial case, H2O2-based processes demonstrate greater efficiency over that of S2O82-, as Anabaena sp. is particularly affected by H2O2, for which >90% of growth inhibition has been achieved with 0.088 mmol/L of H2O2 (at 72 h of exposure). The response of Anabaena sp. as a co-culture with V alginolyticus implies the use of major H2O2 amounts for its inactivation (0.29 mmol/L of H2O2), while the effects of H2O2/Fe(II) suggests an improvement of similar to 60% compared to single H2O2. These H2O2 doses are not sufficient for preventing the regrowth of V alginolyticus after 24 h. The effects of S2O82- (+ Fe(II)) are moderate, reaching maximum inhibition growth of similar to 50% for Anabaena sp. at seven days of exposure. Nevertheless, doses of 3 mmol/L of S2O82- can prevent the regrowth of V alginolyticus. These findings have implications for the mitigation of HABs but also for the associated bacteria that threaten many coastal ecosystems
Determining disinfection efficiency on E. faecalis in saltwater by photolysis of H2O2: Implications for ballast water treatment
Organisms carried with ballast water can find a way that enables them to spread into a new habitat, becoming invasive species. This can generate large impacts threatening the ecosystem and human activities. The effectiveness of microbiological disinfection by UV/H2O2 treatment on Enterococcus faecalis has been evaluated in this study at laboratory scale, in both buffered distilled water (DW) and saltwater (SW). A Collimated Beam Reactor was used to determine optimal H2O2 concentration with DW and a Continuous Flow Reactor was tested with DW and SW. The optimal concentration of hydrogen peroxide found was 5 mg/L. The improvement of adding H2O2 increased efficacy by 28.9% in SW compared with UV alone; while results indicated that water salinity did not induce strong interference in treatment. In addition, re-growth of surviving bacteria was prevented 24 h after the treatment; even an additional one-log inactivation was obtained. The results suggest that the addition of small concentrations of H2O2 leads to an improvement in UV treatment. Finally, the operational costs were estimated for typical cargo vessels; UV/H2O2 treatment was considered to be competitive for ballast water treatment, since it could improve the effectiveness of the process with similar costs per 1000 m3 of treated water: 14 € for UV treatment and 16 € for UV/H2O2 treatmen
Alterations in the glycan profile of mouse transferrin: new insights in collagen-induced arthritis
Transferrin purification from mice serum samples by immunoaffinity chromatography (IAC) was optimized in order to study the possible modifications occurred in its glycans in collagen-induced arthritis (CIA) samples. SDS-PAGE and nanoLC-MS/MS were used to monitor the IAC purification performance. Afterwards, a relative quantification of mouse transferrin (mTf) glycan isomers using [12C6]/[13C6]-aniline was used to unequivocally detect alterations in the glycan profile of CIA mice. In addition, multivariate data analysis was applied to identify the most meaningful glycan isomers for the discrimination between control and pathological samples. Partial least squares discriminant analysis (PLS-DA) revealed that five out of fifteen mTf glycan isomers could be potential biomarkers of CIA, most of them corresponding to highly sialylated structures (H6N5S3_2, H6N5S3_3 and H5N4S3_2). Moreover, some of these glycan isomers also seemed to be related with the progression of CIA, especially H6N5S2 and H6N5S3_2, as their overexpression increased with the clinical score of the pathology. Hence, the established methodology provides valuable information to find glycan-based biomarkers of CIA, but also leaves the door open to evaluate, in the future, glycosylation changes of many other inflammatory diseases, in which transferrin has been described to be altered
UV-based technologies for marine water disinfection and the application to ballast water: Does salinity interfere with disinfection processes?
Water contained on ships is employed in the majority of activities on a vessel; therefore, it is necessary to correctly manage through marine water treatments. Among the main water streams generated on vessels, ballast water appears to be an emerging global challenge (especially on cargo ships) due to the transport of invasive species and the significant impact that the ballast water discharge could have on ecosystems and human activities. To avoid this problem, ballast water treatment must be implemented prior to water discharge in accordance with the upcoming Ballast Water Management Convention. Different UV-based treatments (photolytic: UV-C and UV/H2O2, photocatalytic: UV/TiO2), have been compared for seawater disinfection. E. faecalis is proposed as a biodosimeter organism for UV-based treatments and demonstrates good properties for being considered as a Standard Test Organism for seawater. Inactivation rates by means of the UV-based treatments were obtained using a flow-through UV-reactor. Based on the two variables responses that were studied (kinetic rate constant and UV-Dose reductions), both advanced oxidation processes (UV/H2O2 and photocatalysis) were more effective than UV-C treatment. Evaluation of salinity on the processes suggests different responses according to the treatments: major interference on photocatalysis treatment and minimal impact on UV/H2O2
Evaluating seawater quality objectives: Application to the Andalusian littoral
The University of Cadiz (southern Spain) and the Andalusian Environmental Agency (AMA) have signed an agreement to draw up a proposal of quality objectives for Andalusian littoral waters in accordance with the classification of zones approved in the Andalusian Littoral Waters Quality Objectives Regulations (Decree 14/1996, 01-16-1996, BOJA no. 19, 02-08-1996). The present paper reviews different regulations (European Union, Spain and the United States) concerning seawater quality criteria and presents the quality criteria proposed by the University of Cadiz.La Universidad de Cádiz y la Agencia de Medio Ambiente Andaluza (AMA) han desarrollado un convenio cuya finalidad es la realización de una propuesta de objetivos de calidad para las aguas litorales andaluzas según la clasificación de zonas establecida en el Decreto 14/1996, por el que se aprueba el Reglamento de Calidad de las Aguas Litorales Andaluzas (BOJA n.° 19 de 8 de febrero de 1996). En este trabajo se hace una revisión de la normativa referente a los objetivos de calidad de las aguas marinas en la Unión Europea, España y Estados Unidos. Además, se recoge la propuesta de objetivos de calidad de aguas litorales realizada por la Universidad de Cádiz.Instituto Español de Oceanografí
- …