Second-best tax policy in a growing economy with externalities

This paper investigates the exploitation of environmental resources in a growing economy within a second-best scal policy framework. Agents derive utility from two types of consumption goods one which relies on an environmental input and one which does not as well as from leisure and from environmental amenity values. Property rights for the environmental resource are potentially incomplete. We connect second best policy to essential components of utility by considering the elasticity of substitution among each of the four utility arguments. The results illustrate potentially important relationships between environmental amentity values and leisure. When amenity values are complementary with leisure, for instance when environmental amenities are used for recreation, taxes on extractive goods generally increase over time. On the other hand, optimal taxes on extractive goods generally decrease over time when leisure and environmental amenity values are substitutes. Unders some parameterizations, complex dynamics leading to nonmonotonic time paths for the state variables can emerge.elasticity of substitution, second-best policy, growth and the environment

Arsenic distribution in a pasture area impacted by past mining activities

[EN]Former mine exploitations entail a serious threat to surrounding ecosystems as after closure of mining activities their unmanaged wastes can be a continuous source of toxic trace elements. Quite often these mine sites are found within agricultural farming areas, involving serious hazards as regards product (feed/food) quality. In this work a grazing land impacted by the abandoned mine exploitation of an arsenical deposit was studied so as to evaluate the fate of arsenic (As) and other trace elements and the potential risks involved. With this aim, profile soil samples (0–50 cm) and pasture plant species (Agrostis truncatula, Holcus annus and Leontodon longirostris) were collected at different distances (0–100 m) from the mine waste dump and analyzed for their trace element content and distribution. Likewise, plant trace element accumulation from impacted grazing soils and plant trace element translocation were assessed. The exposure of livestock grazing animals to As was also evaluated, establishing its acceptability regarding food safety and animal health. International soil guideline values for As in grazing land soils (50 mg kg−1) resulted greatly exceeded (up to about 20-fold) in the studied mining-affected soils. Moreover, As showed a high mobilization potential under circumstances such as phosphate application or establishment of reducing conditions. Arsenic exhibited relatively high translocation factor (TF) values (up to 0.32–0.89) in pasture plant species, reaching unsafe concentrations in their above-ground tissues (up to 32.9, 16.9 and 9.0 mg kg−1 in Agrostis truncatula, Leontodon longirostris and Holcus annus, respectively). Such concentrations represent an elevated risk of As transfer to the high trophic-chain levels as established by international legislation. The limited fraction of arsenite found in plant roots should play an important role in the relatively high As root-to-shoot translocation shown by these plant species. Both soil ingestion and pasture intake resulted important entrance pathways of As into livestock animals, showing quite close contribution levels. The cow acceptable daily intake (ADI) of As regarding food safety was surpassed in some locations of the study area when the species Agrostis truncatula was considered as the only pasture feed. Restrictions in the grazing use of lands with considerable As contents where this plant was the predominant pasture species should be established in order to preserve food quality. Therefore, the exposure of livestock animals to As via both soil ingestion and pasture consumption should be taken into account to establish the suitability of mining-impacted areas for gazing

Roman mining works and gold ore deposits in the San Pedro de Olleros sector (El Bierzo, León)

[Abstract] The gold mining in the Bierzo Region, NW Spain had great importance, not only in the well known Las Médulas site, but also in the north sector of El Bierzo Basin, (San Pedro de Olleros Valle de Finolledo). This work have recognised the roman exploitation sites, differentiating the fertile facies within the tertiary sequences. Although no data about ages have still found, an approach to the tectonosedimentary evolutive history is carried out, taking into account the geometry and characteristics of the deposits[Abstract] The gold mining in the Bierzo Region, NW Spain had great importance, not only in the well known Las Médulas site, but also in the north sector of El Bierzo Basin, (San Pedro de Olleros -Valle de Finolledo). This work have recognised the roman exploitation sites, differentiating the fertile facies within the tertiary sequences. Although no data about ages have still found, an approach to the tectonosedimentary evolutive history is carried out, taking into account the geometry and characteristics of the deposit

Floral morphology and development in Aragoa (Plantaginaceae) and related members of the order Lamiales

Inflorescence and floral morphology and development were investigated in Aragoa (Plantaginaceae) and related genera. Each inflorescence of Aragoa is a reduced, axillary raceme, on which the actinomorphic floral apices generally arise successively. The inflorescences of Aragoa and Plantago are polytelic and lateral. The five sepals emerge from the abaxial to the adaxial side of the floral apex, but at maturity, the calyx is actinomorphic. The four stamens arise simultaneously and before emergence of the petals. The four petals emerge unidirectionally united, but the corolla becomes actinomorphic. Aestivation is cochlear ascendent. The two united carpels initiate simultaneously. The abaxial-adaxial inception of the calyx and corolla during early floral development in genera such as Aragoa, Digitalis, Plantago, and Veronica may indicate that the zygomorphic condition is ancestral in those genera. The tetramerous corolla, which is actinomorphic during middle and late development, and the presence of four stamens are possible synapomophies of the clade (Aragoa þ Plantago). Pentamery of the calyx and corolla appears to be plesiomorphic in the broader Aragoa- Angelonia clade. Characters related to development and morphology of inflorescences and flowers of Aragoa are essentially similar to those found in Plantago, which is consistent with the molecular-based sister group relationship between these genera.Peer reviewe

Natusers’ motivations and attitudes in urban green corridors: challenges and opportunities. Case study of the Parc Fluvial del Túria (Spain)

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Magnetic dispersive solid phase microextraction coupled with on-line chemical vapor generation method to extraction/preconcentration of mercury from environmental samples and determination by graphite furnace atomic absorption spectrometry.

Mercury (Hg) is classified as priority hazardous substances. Concentrations found in the aquatic environment are at trace levels as result of natural processes, such as erosion and volcanism, and anthropogenic discharges related mainly to industrial and mining activities. Mercury is one of the most potent neurotoxins known, showing a high number of adverse health effects in animals and humans. For this reason, a simple and rapid method for the determination and preconcentration of mercury in environmental waters is proposed. This work is based on magnetic dispersive solid phase microextraction (MDSPME) coupled with on-line chemical vapour generation (CVG). Graphite furnace atomic absorption spectrometry (GFAAS) was employed for the quantification of Hg. In the preconcentration step, a shell structured Fe3O4@graphene oxide was suspended in the ionic liquid carrier (1-n-butyl-3-metilimidazolium tetrafluoroborate [BMIM][BF4]), obtaining a stable colloidal suspension called ferrofluid. This sorbent possesses as large contact surface area and a high density of polar groups on its surface. The nanoparticles, when finely dispersed in the sample solution, result in almost complete extraction of Hg within a few seconds. All experimental and instrumental variables were optimized and the method was adequately validated by the analysis of certified reference materials of environmental waters. Acknowledgements The authors would like to thank Plan Propio “Proyecto Puente” de la Universidad de Málaga for financial support of this work.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Solid sampling determination of ZnO nanoparticles in eyeshadows by graphite furnace atomic absorption spectrometry

The application of nanoparticles (NPs) in science and technology is a fast growing field. Therefore, reliable and straightforward analytical methods are required for their fast determination in different types of samples. In this work, a method that enables the determination of the average size of ZnO NPs, besides their concentration, discriminating them from ionic zinc, has been optimized. The method is based on solid sampling high-resolution continuum source electrothermal atomic absorption spectrometry (SS-HR-CS-GFAAS), and has been applied to determination and characterization of ZnO NPs in cosmetic samples. Recently, graphite furnace atomic absorption spectrometry has been introduced as a new tool to determine the size of nanoparticles by evaluation of the following parameters: atomization delay (tad) and atomization rate (kat). In this work both parameters (besides peak area) have been obtained from absorbance signals for a line of Zn with low sensitivity. Two multiple response surface designs have been used in order to optimize the adequate furnace program to achieve our aims. All the optimization experiments were performed using baby´s skin irritation protective cream. The optimized furnace program is shown in Table 1. Table 1. Optimized furnace program The size calibrations were performed against solid (powered) ZnO standards, from 50-nm to 500-nm sized nanoparticles. The correlation coefficients (R value) of the linear calibration were not worse than 0.9982. The optimized method was tested in other types of cosmetic samples such as eyeshadow samples with good results. The determination of the MNPs’ size was validated by transmission electron microscopy (TEM) and the Zn concentration in the solid samples was validated by atomic fluorescence spectroscopy (AFS). Acknowledgements (optional) [Garamond font, 10 points] The authors would like to thank Plan propio “Proyecto Puente” de la Universidad de Málaga for financial support of this work.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Rapid magnetic microextraction to preconcentrate and determinate cadmium from environmental samples

A novel and greener ultrasonically assisted/modified cloud point extraction procedure for the preconcentration and extraction of trace cadmium from environmental samples was developed. The sorbent material was fabricated by scattering of magnetic iron nanoparticles (MNPs) over graphene oxide (GO) to obtain magnetic graphene oxide (MGO). The material was suspended in the ionic liquid 1-n-butyl-3-metilimidazolium tetrafluoroborate [BMIM][BF4]. The obtained stable colloidal suspension is named ferrofluid. GO presents excellent adsorbent properties for organic species due to the presence of the electronic π system. For this reason, the organic ligand [1,5-bis-(2-dipyridyl) methylene] thiocarbonohydrazide (DPTH) was used in order to form an organic complex of Cd. Once the DPTH ligand has been added to sample, the ferrofluid was injected and finely dispersed in the sample solution in order to extract the formed chelate as shown in Fig. 1. The complete adsorption of the quelate took place within few seconds, after that the solid was separated from the solution with the aid of a strong magnet. Cadmium ions were desorbed from the material with 1 mL of 5% acid nitric solution and quantified by electrothermal atomic absorption spectrometry (ETAAS). The main parameters affecting the extraction and the furnace program were optimized using one-at-time method. The analytical performance under optimum conditions are the following: LOD: 0.005 µg/L, LOQ: 0.017 µg/L. Linear calibration: 0-0.25 µg/L and EF: 200. The reliability of the developed procedure was tested by relative standard deviation (% RSD), which was found to be < 5% (1.3%). The performance of the proposed procedure was checked by applying to certified reference material and spiking standard in real samplesUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Second-best tax policy in a growing economy with externalities

This paper investigates the exploitation of environmental resources in a growing economy within a second-best scal policy framework. Agents derive utility from two types of consumption goods one which relies on an environmental input and one which does not as well as from leisure and from environmental amenity values. Property rights for the environmental resource are potentially incomplete. We connect second best policy to essential components of utility by considering the elasticity of substitution among each of the four utility arguments. The results illustrate potentially important relationships between environmental amentity values and leisure. When amenity values are complementary with leisure, for instance when environmental amenities are used for recreation, taxes on extractive goods generally increase over time. On the other hand, optimal taxes on extractive goods generally decrease over time when leisure and environmental amenity values are substitutes. Unders some parameterizations, complex dynamics leading to nonmonotonic time paths for the state variables can emerge.Some of this research was supported by the Spanish Ministry of Education and Science, grant number SEJ2006-12793/ECON. 2006-2009, who we thank. Cassou would also like to acknowledge the support and hospitality of Universidad del País Vasco

Fungal spore swelling and germination are restricted by the macrophage phagolysosome

Acknowledgements We acknowledge Wellcome support of Senior Investigator (101873/Z/13/Z; 224323/Z/21/Z), Collaborative (200208/A/15/Z) and Strategic Awards (097377/Z11/Z) and the MRC for a programme grant (MR/M026663/2) and the MRC Centre for Medical Mycology (MR/N006364/2). We thank Kevin Mackenzie for help with microscopy. For the purpose of open access, the author has applied a CC BY public copyright licence to any Author Accepted Manuscript version arising from this submission.Peer reviewedPublisher PD