Resilience of Epiphytic Lichens to Combined Effects of Increasing Nitrogen and Solar Radiation

Lichens are classified into different functional groups depending on their ecological and physiological response to a given environmental stressor. However, knowledge on lichen response to the synergistic effect of multiple environmental factors is extremely scarce, although vital to get a comprehensive understanding of the effects of global change. We exposed six lichen species belonging to different functional groups to the combined effects of two nitrogen (N) doses and direct sunlight involving both high temperatures and ultraviolet (UV) radiation for 58 days. Irrespective of their functional group, all species showed a homogenous response to N with cumulative, detrimental effects and an inability to recover following sunlight, UV exposure. Moreover, solar radiation made a tolerant species more prone to N pollution’s effects. Our results draw attention to the combined effects of global change and other environmental drivers on canopy defoliation and tree death, with consequences for the protection of ecosystems.info:eu-repo/semantics/publishedVersio

Non-Toxic Increases in Nitrogen Availability Can Improve the Ability of the Soil Lichen Cladonia rangiferina to Cope with Environmental Changes

Climate change and atmospheric nitrogen (N) deposition on drylands are greatly threatening these especially vulnerable areas. Soil biocrust-forming lichens in drylands can provide early indicators of these disturbances and play a pivotal role, as they contribute to key ecosystem services. In this study, we explored the effects of different long-term water availability regimes simulating climate changes and their interaction with N addition on the physiological response of the soil lichen Cladonia rangiferina. Three sets of this lichen were subjected to control, reduced watering, and reduced watering and N addition (40 kg NH4NO3 ha−1 year−1) treatments for 16 months. Finally, all samples were subjected to daily hydration cycles with N-enriched water at two levels (40 and 80 kg NH4NO3 ha−1 year−1) for 23 days. We found that reduced watering significantly decreased the vitality of this lichen, whereas N addition unexpectedly helped lichens subjected to reduced watering to cope with stress produced by high temperatures. We also found that long-term exposure to N addition contributed to the acclimation to higher N availability. Overall, our data suggest that the interactions between reduced watering and increased N supply and temperature have an important potential to reduce the physiological performance of this soil lichen.info:eu-repo/semantics/publishedVersio

A transparent TMPyP/TiO2 composite thin film as an HCl sensitive optochemical gas sensor

Tetracationic porphyrin (TMPyP) molecules were incorporated into an optically transparent TiO2 thin film, prepared by Glancing Angle Physical Vapour Deposition (GAPVD), by simple infiltration (at pH 6.4). The preparation of optically transparent TMPyP/TiO2 composite thin films provides a method for the integration of the porphyrin molecules into photonic devices for direct monitoring of gases. Previously, UV-visible and fluorescence spectral techniques have been used to study the reversible protonation of TMPyP in aqueous solution. The optical spectrum of TMPyP shows an intense Soret band at 423 nm with a 22 nm red shift upon protonation by HCl. The experimental conditions for monitoring the concentration of HCl gas by absorption spectroscopy have been optimized. The maximum absorbance change was observed at the Soret band wavelength. A selected temperature of 80 °C and a 300 s recovery period were found to be the optimum operating parameters (response time t50 = 16.8 ± 0.7 s). The composite with smaller surface concentration of TMPyP (¿ = 0.3 × 10-9 mol cm -2) presented the best detection limit (0.1 ppm). The response of the composite sensor was highly stable for several months.Ministerio de Educación y Ciencia PET2007 0363 01/ 02, TEC201021830C0201, CSD20070000

Uso de reactivos colorimétricos como marcadores químicos con importante aplicación industrial.

Colorimetry is a technique used to measure and analyse colours, mainly to determine the concentration of colored compounds in solutions by the application of the Beer–Lambert law. It is applied in a variety of fields, such as chemistry, medicine, biology, and in the pharmaceutical and food industries. The basis of this technique is often the use of colorimetric reagents that provide an easily identifiable colour that depends on factors both internal and external to the samples. These reagents are usually pigments that vary in colour depending on the conditions to which they are subjected. In addition, they can interact with the packaging or the environment in which they are placed. The stimulated colour response becomes a practical tool to assess in real time the status of products in the distribution chain. This is why pigments modulated by other reagents have been applied to measure the colour change of samples applicable to products as quality markers.Pigments and the modulator have been prepared in a hand-made device of plastic nature. The colour change reaction of the pigment has been characterised at different temperatures using water baths and the influence of movement on the sample has been measured by means of orbital shaking. The colour change of the pigment has been measured by means of an RGB device and UV-vis spectrophotometry. Subsequently, real trials will be carried out with volunteers to test the effectiveness of the colourimetric device attached to a product.It has been observed that the reaction kinetics is temperature-dependent. The higher the temperature the shorter the reaction time. The reaction time ranged from 3 to 14 hours at temperatures of 40°C down to 5°C. Stirring does not influence the reaction time.Compounds such as pigments, once modulated, can be an effective tool for monitoring product quality quite accurately. Once the reactants ratios are adjusted to the shelf life of the products, their reliability increases considerably, bringing benefits to the final consumer.NOTE: This work is bound by confidentiality in the framework of a research contract

Optical Gas Sensing of Ammonia and Amines Based on Protonated Porphyrin/TiO2 Composite Thin Films

Open porous and transparent microcolumnar structures of TiO2 prepared by physical vapour deposition in glancing angle configuration (GLAD-PVD) have been used as host matrices for two different fluorescent cationic porphyrins, 5-(N-methyl 4-pyridyl)-10,15,20-triphenyl porphine chloride (MMPyP) and meso-tetra (N-methyl 4-pyridyl) porphine tetrachloride (TMPyP). The porphyrins have been anchored by electrostatic interactions to the microcolumns by self-assembly through the dip-coating method. These porphyrin/TiO2 composites have been used as gas sensors for ammonia and amines through previous protonation of the porphyrin with HCl followed by subsequent exposure to the basic analyte. UV–vis absorption, emission, and time-resolved spectroscopies have been used to confirm the protonation–deprotonation of the two porphyrins and to follow their spectral changes in the presence of the analytes. The monocationic porphyrin has been found to be more sensible (up to 10 times) than its tetracationic counterpart. This result has been attributed to the different anchoring arrangements of the two porphyrins to the TiO2 surface and their different states of aggregation within the film. Finally, there was an observed decrease of the emission fluorescence intensity in consecutive cycles of exposure and recovery due to the formation of ammonium chloride inside the film.We thank the Junta de Andalucía (Project: FQM-2310), the European Regional Development Funds program (EU-FEDER) and the Spanish Ministry of Economy and Competitiveness (Projects: MAT2013-40852-R, MAT2013-42900-P, MAT2014-57652-C2-2-R, MAT2015-69035-REDC, MINECO-CSIC 201560E055, PCIN-2015-169-C02-02 under a 2014 M-Era.Net project and RECUPERA 2020), for financial support. We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)

Development and fine-tuning of an artificial organoleptic analysis method for virgin olive oil using an electronic olfactory system

Motivation: The catalogation of olive oil by organoleptic parameters has a high grade of subjection because of human factor. A new system of electronic tasting is used as a reliable, fast and cheap method. The use of an electronic olfatory system (EOS), which consist of an array of electonic sensors and a mechanism for pattern recognition, requires of a previous training process like a human olfatory system. The training is one of the most relevant and delicated phase, as this process involves the creation of a complete database that the instrument uses as a reference for the subsequent sample recognition.Methods: A set of samples of different olive oils were analysed by three official panel tests before using the EOS. The instrument is composed of a chamber with five metal oxide semiconductor based sensors. During the analysis, each sensor is maintained at a specific temperature showing a different response for a certain sample, which implies a reduction in the sensors resistance. For the measurement, volatile compounds were directed to the sensor chamber by the carrier gas (dry air). Principal component analyses to interpret the datasets from the EOS is employed in order to assess the classification of the measurements.A database was created through the analysis of a set of samples which should be representative of differents aromas to be recognized.Conclusions: The main conclussion is the high variability between the official panel tests which could be reduced by the EOS. From the database that was created we can analyse an olive oil with unknown catalogation and classify into Extra Virgin, virgin or lampante.On-line detection of the different categories, during the oil industrial process, could have a notable economical impact

Optical gas sensing of ammonia and amines based on protonated porphyrin/TiO2 composite thin films

Open porous and transparent microcolumnar structures of TiO2 prepared by physical vapour deposition in glancing angle configuration (GLAD-PVD) have been used as host matrices for two different fluorescent cationic porphyrins, 5-(N-methyl 4-pyridyl)-10,15,20-triphenyl porphine chloride (MMPyP) and meso-tetra (N-methyl 4-pyridyl) porphine tetrachloride (TMPyP). The porphyrins have been anchored by electrostatic interactions to the microcolumns by self-assembly through the dip-coating method. These porphyrin/TiO2 composites have been used as gas sensors for ammonia and amines through previous protonation of the porphyrin with HCl followed by subsequent exposure to the basic analyte. UV–vis absorption, emission, and time-resolved spectroscopies have been used to confirm the protonation–deprotonation of the two porphyrins and to follow their spectral changes in the presence of the analytes. The monocationic porphyrin has been found to be more sensible (up to 10 times) than its tetracationic counterpart. This result has been attributed to the different anchoring arrangements of the two porphyrins to the TiO2 surface and their different states of aggregation within the film. Finally, there was an observed decrease of the emission fluorescence intensity in consecutive cycles of exposure and recovery due to the formation of ammonium chloride inside the film.Junta de Andalucía FQM-2310EU-FEDERMinisterio de Economía y Competitividad MAT2013-42900-P MAT2014-57652-C2-2-R MAT2015-69035-REDC MINECO-CSIC 201560E055 PCIN-2015-169-C02-0

Nitrogen Deposition Effects on Soil Properties, Microbial Abundance, and Litter Decomposition Across Three Shrublands Ecosystems From the Mediterranean Basin

Atmospheric nitrogen (N) inputs in the Mediterranean Basin are projected to increase due to fossil fuel combustion, fertilizer use, and the exacerbation of agricultural production processes. Although increasing N deposition is recognized as a major threat to ecosystem functioning, little is known about how local environmental conditions modulate ecosystem function response to N addition, particularly in the context of Mediterranean-Basin ecosystems. Here, we assess how N addition affects important ecosystem properties associated with litter decomposition, soil physical-chemical properties, soil extracellular enzymatic activity and microbial abundance across three long-term N addition experimental sites in the Mediterranean Basin. Sites were located in El Regajal (Madrid, Spain), Capo Caccia (Alghero, Italy), and Arrábida (Lisbon, Portugal) and are all representative of Mediterranean shrublands. No common pattern for litter decomposition process or other studied variables emerged among the control plots of the studied sites. Nitrogen supply only affected soil pH, a major driver of decomposition, in two out of three experimental sites. Moreover, when we explored the role of N addition and soil pH in controlling litter decay, we found that the effects of these factors were site-dependent. Our results point out to local ecosystem features modulating N addition effects in controlling litter decomposition rates in Mediterranean ecosystems, suggesting that the responses of soil functioning to N deposition are site-dependent. These findings provide further knowledge to understand contrasting ecosystem responses to N additions based on a single field experiments

A selective defect in the glial wedge as part of the neuroepithelium disruption in hydrocephalus development in the mouse hyh model is associated with complete corpus callosum dysgenesis

IntroductionDysgenesis of the corpus callosum is present in neurodevelopmental disorders and coexists with hydrocephalus in several human congenital syndromes. The mechanisms that underlie the etiology of congenital hydrocephalus and agenesis of the corpus callosum when they coappear during neurodevelopment persist unclear. In this work, the mechanistic relationship between both disorders is investigated in the hyh mouse model for congenital hydrocephalus, which also develops agenesis of the corpus callosum. In this model, hydrocephalus is generated by a defective program in the development of neuroepithelium during its differentiation into radial glial cells.MethodsIn this work, the populations implicated in the development of the corpus callosum (callosal neurons, pioneering axons, glial wedge cells, subcallosal sling and indusium griseum glial cells) were studied in wild-type and hyh mutant mice. Immunohistochemistry, mRNA in situ hybridization, axonal tracing experiments, and organotypic cultures from normal and hyh mouse embryos were used.ResultsOur results show that the defective program in the neuroepithelium/radial glial cell development in the hyh mutant mouse selectively affects the glial wedge cells. The glial wedge cells are necessary to guide the pioneering axons as they approach the corticoseptal boundary. Our results show that the pioneering callosal axons arising from neurons in the cingulate cortex can extend projections to the interhemispheric midline in normal and hyh mice. However, pioneering axons in the hyh mutant mouse, when approaching the area corresponding to the damaged glial wedge cell population, turned toward the ipsilateral lateral ventricle. This defect occurred before the appearance of ventriculomegaly.DiscussionIn conclusion, the abnormal development of the ventricular zone, which appears to be inherent to the etiology of several forms of congenital hydrocephalus, can explain, in some cases, the common association between hydrocephalus and corpus callosum dysgenesis. These results imply that further studies may be needed to understand the corpus callosum dysgenesis etiology when it concurs with hydrocephalus

Nitrogen deposition effects on soil properties, microbial abundance, and litter decomposition across three shrublands ecosystems from the Mediterranean Basin

Atmospheric nitrogen (N) inputs in the Mediterranean Basin are projected to increase due to fossil fuel combustion, fertilizer use, and the exacerbation of agricultural production processes. Although increasing N deposition is recognized as a major threat to ecosystem functioning, little is known about how local environmental conditions modulate ecosystem function response to N addition, particularly in the context of Mediterranean-Basin ecosystems. Here, we assess how N addition affects important ecosystem properties associated with litter decomposition, soil physical-chemical properties, soil extracellular enzymatic activity and microbial abundance across three long-term N addition experimental sites in the Mediterranean Basin. Sites were located in El Regajal (Madrid, Spain), Capo Caccia (Alghero, Italy), and Arrábida (Lisbon, Portugal) and are all representative of Mediterranean shrublands. No common pattern for litter decomposition process or other studied variables emerged among the control plots of the studied sites. Nitrogen supply only affected soil pH, a major driver of decomposition, in two out of three experimental sites. Moreover, when we explored the role of N addition and soil pH in controlling litter decay, we found that the effects of these factors were site-dependent. Our results point out to local ecosystem features modulating N addition effects in controlling litter decomposition rates in Mediterranean ecosystems, suggesting that the responses of soil functioning to N deposition are sitedependent. These findings provide further knowledge to understand contrasting ecosystem responses to N additions based on a single field experiments