433 research outputs found
Phantom Membrane Microfluidic Cross-Flow Filtration Device for the Direct Optical Detection of Water Pollutants
The diffusion of autonomous sensing platforms capable of a remote large-scale surveillance of environmental water basins is currently limited by the cost and complexity of standard analytical methods. In order to create a new generation of water analysis systems suitable for continuous monitoring of a large number of sites, novel technical solutions for fluid handling and detection are needed. Here we present a microfluidic device hosting a perfluorinated microporous membrane with refractive index similar to that of water, which enables the combination of filtration and label-free sensing of adsorbing substances, mainly pollutants, in environmental water samples. The cross-flow design of the microfluidic device avoids the clogging of the membrane due to particulate, whereas molecules with some hydrophobic moiety contained in the crossing flow are partially retained and their adhesion on the inner surface of the membrane yields an increase of light scattering intensity, which can be easily measured using a simple instrument based on Light Emitting Diode illumination. By cycling sample water and pure water as a reference, we demonstrate the detection of 0.5 microM of a model cationic surfactant and regeneration of the sensing surface. The optical response of the membrane sensor was characterized using a simple theoretical model that enables to quantify the concentration of target molecules from the amplitude and kinetics of the measured binding curves. The device was tested with real water samples containing large amount of environmental particles, without showing clogging of the membrane, and enabling nonspecific quantification of adsorbing substances in a few minutes.This project has received funding from the European Union’s Seventh Framework Programme (FP7) for Research, Technological Development and Demonstration through the NAPES project(grant agreement no. 604241). FBL acknowledges the Ramón y CajalProgramme (Ministerio de EconomÃa y Competitividad), Spain. FBL personally acknowledges to Elkartek (KK-2015/00088) Grant from the Gobierno Vasco and funding support from Gobierno de España, Ministerio de Economia y Competitividad, with Grant No. BIO2016-80417-P and to Marian M. De Pancorbo for letting him to use her laboratory facilities at UPV/EHU. PSA was generously provided byAdhesive Research, Ireland. We thank Aurora Giavazzi for helping in the collection of river water samples
Coherence Extrapolation for Underwater Ambient Noise
This paper considers extrapolation of the vertical coherence of surface-generated oceanic ambient noise to simulate measurements made on a longer sensor array. The extrapolation method consists of projecting the noise coherence measured with a limited aperture array into the domain spanned by prolate spheroidal wave functions, which are an orthogonal basis defined by array parameters and the noise frequency. Using simulated data corresponding to selected multi-layered seabeds as ground truth, the performance of the extrapolation method is explored. Application of the technique is also demonstrated on experimental data
Records of spiders (Arachnida : Araneae) from the Maltese Islands (Central Mediterranean)
Following a brief review of the literature on Maltese Araneae, a list of species which have been confirmed as occurring in the Maltese Islands is given. This list is based on the taxonomic literature and on material in the authors' collections; in the latter case locality and collection data are included. The list comprises 74 species belonging to 21 families. The male palp and female epigyne of a number of species are illustrated.peer-reviewe
Zinc ions alter morphology and chitin deposition in an ericoid fungus
A sterile mycelium PS IV, an ascomycete capable of establishing ericoid mycorrhizas, was used to investigate how zinc ions affect the cellular mechanisms of fungal growth. Asignificant reduction of the fungal biomass was observed in the presence of millimolar zinc concentrations; this mirrored conspicuous changes in hyphal morphology which led to apical swellings and increased branching in the subapical parts. Specific probes for fluorescence and electron microscopy localised chitin, the main cell wall polysaccharide, on the inner part of the fungal wall and on septa in control specimens. In Zn-treated mycelium, hyphal walls were thicker and a more intense chitin labelling was detected on the transverse walls. Aquantitative assay showed a significant increase in the amount of chitin in metal- treated hyphae
Phantom membrane microfluidic cross-flow filtration device for the direct optical detection of water pollutants
The diffusion of autonomous sensing platforms capable of a remote large-scale surveillance of environmental water basins is currently limited by the cost and complexity of standard analytical methods. In order to create a new generation of water analysis systems suitable for continuous monitoring of a large number of sites, novel technical solutions for fluid handling and detection are needed. Here we present a microfluidic device hosting a perfluorinated microporous membrane with refractive index similar to that of water, which enables the combination of filtration and label-free sensing of adsorbing substances, mainly pollutants, in environmental water samples. The cross-flow design of the microfluidic device avoids the clogging of the membrane due to particulate, whereas molecules with some hydrophobic moiety contained in the crossing flow are partially retained and their adhesion on the inner surface of the membrane yields an increase of light scattering intensity, which can be easily measured using a simple instrument based on Light Emitting Diode illumination. By cycling sample water and pure water as a reference, we demonstrate the detection of 0.5 \uce\ubcM of a model cationic surfactant and regeneration of the sensing surface. The optical response of the membrane sensor was characterized using a simple theoretical model that enables to quantify the concentration of target molecules from the amplitude and kinetics of the measured binding curves. The device was tested with real water samples containing large amount of environmental particles, without showing clogging of the membrane, and enabling nonspecific quantification of adsorbing substances in a few minutes
Type-B monoamine oxidase inhibitors in neurological diseases: clinical applications based on preclinical findings
Type-B monoamine oxidase inhibitors, encompassing selegiline, rasagiline, and safinamide, are available to treat Parkinson's disease. These drugs ameliorate motor symptoms and improve motor fluctuation in the advanced stages of the disease. There is also evidence supporting the benefit of type-B monoamine oxidase inhibitors on non-motor symptoms of Parkinson's disease, such as mood deflection, cognitive impairment, sleep disturbances, and fatigue. Preclinical studies indicate that type-B monoamine oxidase inhibitors hold a strong neuroprotective potential in Parkinson's disease and other neurodegenerative diseases for reducing oxidative stress and stimulating the production and release of neurotrophic factors, particularly glial cell line-derived neurotrophic factor, which support dopaminergic neurons. Besides, safinamide may interfere with neurodegenerative mechanisms, counteracting excessive glutamate overdrive in basal ganglia motor circuit and reducing death from excitotoxicity. Due to the dual mechanism of action, the new generation of type-B monoamine oxidase inhibitors, including safinamide, is gaining interest in other neurological pathologies, and many supporting preclinical studies are now available. The potential fields of application concern epilepsy, Duchenne muscular dystrophy, multiple sclerosis, and above all, ischemic brain injury. The purpose of this review is to investigate the preclinical and clinical pharmacology of selegiline, rasagiline, and safinamide in Parkinson's disease and beyond, focusing on possible future therapeutic applications
Vertedero de residuos sólidos urbanos: Pedogénesis comparada entre sitios de una plantación de Eucalyptus camaldulensis Dehnh. y de vegetación herbácea naturalizad
The purpose of this work was compared different levels of pedogenetics process between sites with Eucalyptus camaldulensis plantation and naturalized grass. The trial was installed on landfill soil cover in Villa DomÃnico, Buenos Aires Province, Argentine, CEAMSE, 34°40’S,50’’; 58°18’45’’W; 4m osl. At five age of trees and forteen of the Landfill was realized the following determination: 1- Physical and Chemicals caracterization of own microsite tree and analogical microsite without trees influence. 2- Biomass root system of trees and naturalized herbaceus vegetation; 3- Microrganims qualitative evaluation in trees rhizosphere and 4- Survival trees and its developpmen as too patologycal and physiological damage. The results showing the antropyc evolution soil with ability to support life on differents espression. It was registred the culturals horizon in the cover landfill generated through the time. Exits the advantage about this process in the microsites tree more than the microsites grass.El objetivo de este trabajo fue comparar distintos niveles de procesos pedogenéticos entre sitios con una plantación de Eucalyptus camaldulensis y otros con vegetación herbácea naturalizada. El experimento se ubicó en la cubierta del vertedero de residuos sólidos urbanos de Villa DomÃnico, Buenos Aires, Argentina, (34 o 40’ 50’’ S; 58º 18’ 45’’W; 4 m snm). A las edades de seis años de la plantación y 14 del vertedero de residuos sólidos urbanos, fueron realizadas las siguientes determinaciones: 1- Caracterización fÃsico quÃmica de micrositios análogos con influencia del árbol y del pastizal naturalizado; 2- Biomasa radicular de árboles y tapiz herbáceo naturalizado; 3- Evaluación cualitativa de microorganismos rizosféricos y 4- Desarrollo y estado sanitario de los árboles. Los resultados mostraron capacidad de soporte biológico producido por una marcada evolución pedogenética antrópica. Se registraron horizontes culturales dentro de la cubierta del vertedero de residuos sólidos urbanos a través del tiempo. Existió una ventaja de estos procesos en los micrositios con árboles respecto de los pastizales
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