Determination of monomethylmercury from seawater with ascorbic acid-assisted direct ethylation

Author Posting. © Association for the Sciences of Limnology and Oceanography, 2014. This article is posted here by permission of Association for the Sciences of Limnology and Oceanography for personal use, not for redistribution. The definitive version was published in Limnology and Oceanography: Methods 12 (2014): 1-9, doi:10.4319/lom.2014.12.1.We developed a technique to measure monomethylmercury (MMHg) concentrations from small volumes (180 mL) of seawater at low femtomolar concentrations using direct ethylation derivitization, decreasing the required volume by 90% from current methods while maintaining a 5 fM detection limit. In this method, addition of ascorbic acid before derivitization of MMHg allows for full recovery of MMHg from the seawater matrix without the need for sample distillation or extraction. The small sample size and relative ease of detection are ideal both for shipboard as well as shore-based measurements of preserved MMHg samples. Combined with shipboard determination of dimethylmercury (DMHg) and elemental mercury (Hg(0)), this method can be used to determine full marine mercury speciation.This research was supported by a National Science Foundation grant (OCE-1031271) awarded to C. H. L. and Mak Saito and a Graduate Research Fellowship awarded to K. M. M

Impact of new synthesized analogues of dehydroacetic acid on growth rate and vomitoxin accumulation by Fusarium graminearum under different temperatures in maize hybrid

Previous work indicated that some of the new synthesized analogues of dehydroacetic acid (DHA) were inhibitory to the growth of mycotoxin producing moulds and accumulation of aflatoxin B1 (AFB1) and ochratoxin A (OTA). The objective of this study was to determine the specific new synthesized chemical compounds that may be effective against mould growth and vomitoxin (deoxynivalenol) (DON) accumulation by Fusarium graminearum. The effect of the investigated 3-/2-aminophenylamine-(ptoluoyl)- 4-hydroxy-6-(p-tolyl)-2H- pyrane-2-one (Schiff base) and 4-hydroxy-3-(p-toluoyl)-6-(p-tolil)-2Hpyrane- 2-one (DHT) on growth and DON accumulation were studied using a mould F. graminearum ZMPBF 1244 and maize grain hybrid to determine the possible use of these compounds as a mean of controlling DON accumulation. Schiff base was inhibitory at 0.05 and 0.1 μg/g and DHT at 0.5 μg/g of maize grain. The inhibitory effect of these substances was judged to be the inhibition of growth rather than toxin accumulation. When growth occurred after a delay, DON accumulation occurred when the cultures reached secondary metabolism. Given sufficient time, cultures which were inhibited initially, but which subsequently inhibited their growth, produced toxin levels equivalent to the control cultures. Levels of the Schiff base above 0.2 μg/g almost completely inhibited mould growth or permitted only a small amount of growth that never reached secondary metabolism and never produced DON during the time of this study.Key words: Fusarium graminearum, vomitoxin, Schiff base, chitin, Artemia salina

BiodiverCities: A roadmap to enhance the biodiversity and green infrastructure of European cities by 2030

BiodiverCities is a European Parliament Pilot Project, developed with the aim of enhancing the use of Urban Green Infrastructure (UGI) to enhance the condition of urban ecosystems, providing benefits for people and nature. In this report, an evaluation around the most appropriate reporting unit for an urban ecosystems assessment is carried out, comparing Functional Urban Areas (FUA) and Local Administrative Units (LAU). Furthermore, UGI are assessed from a multi-scale perspective. The status and scenarios of UGI in European urbanised areas is first analysed measuring the urban green areas and the tree canopy cover. Secondly, the contribution of UGI to the overall European Green Infrastructure (EU-GI) is quantified, evaluating the respective role of FUA and LAU. Finally, the effect of urban characteristics on biotic homogenization is analysed exploring how urbanised areas impact on avian population and communities in French cities. The results of this study will inform the development of a roadmap for greening cities in Europe in the 2020-2030 decade

Edge Diffraction, Trace Formulae and the Cardioid Billiard

We study the effect of edge diffraction on the semiclassical analysis of two dimensional quantum systems by deriving a trace formula which incorporates paths hitting any number of vertices embedded in an arbitrary potential. This formula is used to study the cardioid billiard, which has a single vertex. The formula works well for most of the short orbits we analyzed but fails for a few diffractive orbits due to a breakdown in the formalism for certain geometries. We extend the symbolic dynamics to account for diffractive orbits and use it to show that in the presence of parity symmetry the trace formula decomposes in an elegant manner such that for the cardioid billiard the diffractive orbits have no effect on the odd spectrum. Including diffractive orbits helps resolve peaks in the density of even states but does not appear to affect their positions. An analysis of the level statistics shows no significant difference between spectra with and without diffraction.Comment: 25 pages, 12 Postscript figures. Published versio

EU-wide methodology to map and assess ecosystem condition

The EU Biodiversity Strategy for 2030 calls for developing an EU-wide methodology to map, assess and achieve good condition of ecosystems, so they can deliver benefits to society through the provision of ecosystem services. The EU-wide methodology presented in this report addresses this methodological gap. The EU-wide methodology has adopted the System of Environmental Economic Accounting - Ecosystem Accounting (SEEA EA) as reference framework. The SEEA EA is an integrated framework for organizing biophysical information about ecosystems, adopted as a global statistical standard by the United Nations. The SEEA EA is also the reference framework under the proposal for the amendment of Regulation (EU) No 691/2011 on European environmental economic accounts. Building on previous work done within the MAES initiative, the EU-wide methodology presents useful insights to operationalise the SEEA EA at EU level by integrating different EU data streams in a consistent way with this global statistical standard to consistently map and assess ecosystem condition in the EU across all ecosystem types. The adoption of the SEEA EA framework offers the flexibility to integrate different data flows, leveraging the use of available EU data, such as data reported by MS under EU legislation and EU geospatial data. The EU-wide methodology. The implementation of the EU-wide methodology, making use of available data, will provide the scientific knowledge base to support a range of policies and legal instruments

Transformation tools enabling the implementation of nature-based solutions for creating a resourceful circular city

The linear pattern of production-consumption-disposal of cities around the world will continue to increase the emission of pollutants and stocks of waste, as well as to impact on the irreversible deterioration of non-renewable stocks of raw materials. A transition towards a circular pattern proposed by the concept of ‘Circular Cities’ is gaining momentum. As part of this urban transition, the emergent use of Nature-based Solutions (NBS) intends to shift public opinion and utilize technology to mitigate the urban environmental impact. In this paper, an analysis of the current research and practical investments for implementing NBS under the umbrella of Circular Cities is conducted. A combined appraisal of the latest literature and a survey of ongoing and completed National-European research and development projects provides an overview of the current enabling tools, methodologies, and initiatives for public engagement. It also identifies and describes the links between facilitators and barriers with respect to existing policies and regulations, public awareness and engagement, and scientific and technological instruments. The paper concludes introducing the most promising methods, physical and digital technologies that may lead the way to Sustainable Circular Cities. The results of this research provide useful insight for citizens, scientists, practitioners, investors, policy makers, and strategists to channel efforts on switching from a linear to a circular thinking for the future of cities

Detection of the blazar S4 0954+65 at very-high-energy with the MAGIC telescopes during an exceptionally high optical state

The very high energy (VHE ¿ 100 GeV) -ray MAGIC observations of the blazar S4 0954+65, were triggered by an exceptionally high flux state of emission in the optical. This blazar has a disputed redshift of z = 0.368 or z ¿ 0.45 and an uncertain classification among blazar subclasses. The exceptional source state described here makes for an excellent opportunity to understand physical processes in the jet of S4 0954+65 and thus contribute to its classification. Methods. We investigated the multiwavelength (MWL) light curve and spectral energy distribution (SED) of the S4 0954+65 blazar during an enhanced state in February 2015 and have put it in context with possible emission scenarios. We collected photometric data in radio, optical, X-ray, and ¿-ray. We studied both the optical polarization and the inner parsec-scale jet behavior with 43 GHz data. Results. Observations with the MAGIC telescopes led to the first detection of S4 0954+65 at VHE. Simultaneous data with Fermi-LAT at high energy ¿-ray(HE, 100 MeV < E < 100 GeV) also show a period of increased activity. Imaging at 43 GHz reveals the emergence of a new feature in the radio jet in coincidence with the VHE flare. Simultaneous monitoring of the optical polarization angle reveals a rotation of approximately 100. Conclusions. The high emission state during the flare allows us to compile the simultaneous broadband SED and to characterize it in the scope of blazar jet emission models. The broadband spectrum can be modeled with an emission mechanism commonly invoked for flat spectrum radio quasars (FSRQs), that is, inverse Compton scattering on an external soft photon field from the dust torus, also known as external Compton. The light curve and SED phenomenology is consistent with an interpretation of a blob propagating through a helical structured magnetic field and eventually crossing a standing shock in the jet, a scenario typically applied to FSRQs and low-frequency peaked BL Lac objects (LBL). © ESO 2018.The financial support of the German BMBF and MPG, the Italian INFN and INAF, the Swiss National Fund SNF, the ERDF under the Spanish MINECO (FPA2015-69818-P, FPA2012-36668, FPA2015-68378-P, FPA2015-69210-C6-2-R, FPA2015-69210-C6-4-R, FPA2015-69210-C6-6-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2015-71662-C2-2-P, CSD2009-00064), and the Japanese JSPS and MEXT is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia “Severo Ochoa” SEV-2012-0234 and SEV-2015-0548, and Unidad de Excelencia “María de Maeztu” MDM-2014-0369, by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project 13.12.1.3.02, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, the Polish National Research Centre grant UMO-2016/22/M/ST9/00382 and by the Brazilian MCTIC, CNPq, and FAPERJ. IA acknowledges support by a Ramón y Cajal grant of the Ministerio de Economía, Industria y Competitividad (MINECO) of Spain. The research at the IAA–CSIC was supported in part by the MINECO through grants AYA2016–80889–P, AYA2013–40825–P, and AYA2010–14844, and by the regional government of Andalucía through grant P09–FQM–4784.Peer Reviewe

Discovery of TeV γ-ray emission from the neighbourhood of the supernova remnant G24.7+0.6 by MAGIC

SNR G24.7+0.6 is a 9.5 kyrs radio and gamma-ray supernova remnant evolving in a dense medium. In the GeV regime, SNR G24.7+0.6 (3FHL J1834.1– 0706e/FGES J1834.1–0706) shows a hard spectral index (Γ∼2) up to 200 GeV, which makes it a good candidate to be observed with Cherenkov telescopes such as MAGIC. We observed the field of view of SNR G24.7+0.6 with the MAGIC telescopes for a total of 31 hours. We detect very high energy γ-ray emission from an extended source located 0.34 degree away from the center of the radio SNR. The new source, named MAGIC J1835–069 is detected up to 5 TeV, and its spectrum is well-represented by a power-law function with spectral index of 2.74 ± 0.08. The complexity of the region makes the identification of the origin of the very-high energy emission difficult, however the spectral agreement with the LAT source and overlapping position at less than 1.5 sigma point to a common origin. We analysed 8 years of Fermi-LAT data to extend the spectrum of the source down to 60 MeV. Fermi-LAT and MAGIC spectra overlap within errors and the global broad band spectrum is described by a power-law with exponential cutoff at 1.9 ± 0.5 TeV. The detected γ-ray emission can be interpreted as the results of proton-proton interaction between the supernova and the CO-rich surrounding