Publications

Abstract\n We report on spatially resolved electron energy-loss spectroscopy studies of optical modes in individual star-shaped gold nanoparticles. We studied different morphologies, ranging from a spheroid to well-developed nanostars. For each shape, essentially two groups of modes are appearing: the first one is localized around the core of the nanostars and has an energy slightly less than the quasi-static dipolar mode of a gold sphere (about 2.2 eV); in the second group, the modes are localized at the end of the nanostar tips, with varying energies depending on the geometry of each tip and with energy down to 1.2 eV. The localization of the tip modes is interpreted with the help of boundary element methods simulations.

Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant whose potential toxicity is causing great concern. In the present study, we used two crustaceans (Daphnia magna, Siriella armata), echinoid embryos (Paracentrotus lividus) and turbot (Scophthalmus maximus L.) embryos and larvae to investigate the acute toxicity of this compound. The marine species S. armata exhibited greater sensitivity than the freshwater species D. magna. In the 48-h acute toxicity test the median lethal concentration was 10.96 mg/L for S. armata and 87.46 mg/L for D. magna. In the 96h toxicity test, turbot showed the lowest EC50 (0.155 mgL-1), whilst the EC50 for S. armata was 7.92 mgL-1 which was approximately three times lower than that for sea urchin (24.12 mgL-1). The EC10 values were estimated as 0.032 mgL-1, 4.23 mgL-1 and 45.21 mgL-1 for turbot, Siriella and daphnia, respectively. The LOEC values were 75 µgL-1, 2.5 mgL-1 and 75 mgL-1 (p< 0.05) for turbot, daphnia, and Siriella, respectively. The NOEC values were estimated at 37.5 µgL-1, 1.25 mgL-1 and 50 mgL-1 (p< 0.05) for turbot, Siriella and daphnia, respectively. The order of acute toxicity was: turbot > S. armata > sea urchin > Daphnia magna. This result highlights the importance of including a marine fish in the battery of species to describe the toxicity of these compounds. Considering the persistent nature of PFOS, more research is required to determine potential consequences of long-term exposure to these compounds in aquatic ecosystems.

Seasonings such as naturally fermented soy sauce without added monosodium glutamate (MSG), are currently a growth market in China. However, fraudulent and mislabeled zero-added MSG soy sauce may cause a risk of excessive MSG intake, increasing food safety issues for consumers. This study investigates stable carbon and nitrogen isotopes and 16 amino acids in typical Chinese in-market soy sauces and uses a similarity method to establish criteria to authenticate MSG addition claims. Results reveal most zero-added MSG soy sauces had lower δ¹³C values (-25.2 ‰ to -17.7 ‰) and glutamic acid concentrations (8.97 mg mL^-1 to 34.76 mg mL^-1), and higher δ¹⁵N values (-0.27 ‰ +0.95 ‰) and other amino acid concentrations than added-MSG labeled samples. A combined approach, using isotopes, amino acids, similarity coefficients and uncertainty values, was evaluated to rapidly and accurately identify zero-added MSG soy sauces from MSG containing counterparts.

The honey bee is an important economic insect due to its role in pollinating many agricultural plants. Unfortunately, bees are susceptible to many pathogens, including pests, parasites, bacteria, and viruses, most of which exert a destructive impact on thousands of colonies. The occurrence of resistance to the therapeutic substances used against these organisms is rising, and the residue from these chemicals may accumulate in honey bee products, subsequently affecting the human health. There is current advice to avoid the use of antibiotics, antifungals, antivirals, and other drugs in bees, and therefore, it is necessary to develop alternative strategies for the treatment of bee diseases. In this context, the impact of nosema diseases (nosemosis) on bee health and the negative insults of existing drugs are discussed. Moreover, attempts to combat nosema through the use of alternative compounds, including essential oils, plant extracts, and microbes in vitro and in vivo, are documented.

Abstract The dynamics of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) transmission are influenced by a variety of factors, including social restrictions and the emergence of distinct variants. In this study, we delve into the origins and dissemination of the Alpha, Delta, and Omicron‐BA.1 variants of concern in Galicia, northwest Spain. For this, we leveraged genomic data collected by the EPICOVIGAL Consortium and from the GISAID database, along with mobility information from other Spanish regions and foreign countries. Our analysis indicates that initial introductions during the Alpha phase were predominantly from other Spanish regions and France. However, as the pandemic progressed, introductions from Portugal and the United States became increasingly significant. The number of detected introductions varied from 96 and 101 for Alpha and Delta to 39 for Omicron‐BA.1. Most of these introductions left a low number of descendants (&lt;10), suggesting a limited impact on the evolution of the pandemic in Galicia. Notably, Galicia's major coastal cities emerged as critical hubs for viral transmission, highlighting their role in sustaining and spreading the virus. This research emphasizes the critical role of regional connectivity in the spread of SARS‐CoV‐2 and offers essential insights for enhancing public health strategies and surveillance measures.

ABSTRACT Genomic surveillance and epidemiology have shed light on the viral diversity driving coronavirus disease 2019 (COVID-19) outbreaks and are important during waves of highly transmissible and immune-escaping variants of interest or of concern (VOCs). We analyzed the epidemiological data of the understudied country of Malta and related the patterns observed with viral genetic sequences obtained through the surveillance system headed by the Mater Dei Hospital and the University of Malta. We reconstructed the evolutionary history and spatiotemporal dynamics of Maltese severe acute respiratory syndrome coronavirus 2 viruses using a phylodynamics framework. Our findings suggest that the number of cases associated with B.1.1.7/Alpha, B.1.617.2.X/Delta, and B.1.1.529.X/Omicron VOCs was nine times higher than those associated with wild-type variants. The positivity rates in Malta remained low to moderate (&lt;10%). A combination of public health interventions appeared to have allowed Malta to mitigate the impact of COVID-19. Our phylodynamic reconstruction traced most of the 173 viral introductions inferred to countries in Northern Europe, which is consistent with flight connectivity patterns. We also observed prolonged periods of cryptic transmission (median = 102 days) until expansion into larger outbreaks. These larger outbreaks were more easily detected by the intermittent genomic surveillance in Malta, characterized by periods of sequencing hiatus. Our study demonstrates that integrating epidemiological and genomic data are crucial for uncovering the COVID-19 dynamics of understudied locations, particularly when genomic surveillance is suboptimal. Accordingly, strengthening the genomic surveillance system in Malta should help in the earlier detection of introductions and minimize viral expansion in the country while informing public health interventions. IMPORTANCE Our study provides insights into the evolution of the coronavirus disease 2019 (COVID-19) pandemic in Malta, a highly connected and understudied country. We combined epidemiological and phylodynamic analyses to analyze trends in the number of new cases, deaths, tests, positivity rates, and evolutionary and dispersal patterns from August 2020 to January 2022. Our reconstructions inferred 173 independent severe acute respiratory syndrome coronavirus 2 introductions into Malta from various global regions. Our study demonstrates that characterizing epidemiological trends coupled with phylodynamic modeling can inform the implementation of public health interventions to help control COVID-19 transmission in the community.

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 362:211-223 (2008) - DOI: https://doi.org/10.3354/meps07433 Genetic variation of the spiny spider crab Maja brachydactyla in the northeastern Atlantic Graciela Sotelo1,*, Paloma Morán1, Luis Fernández2, David Posada1 1Departamento de Bioquímica, Genética e Inmunología, Facultad de Biología, Campus Lagoas-Marcosende, Universidad de Vigo, 36310 Vigo, Spain 2Departamento de Biología Animal, Biología Vegetal y Ecología, Campus A Zapateira, Universidad de A Coruña, 15071 A Coruña, Spain *Email: gsotelo@uvigo.es ABSTRACT: The spiny spider crab Maja brachydactyla is a decapod crustacean that inhabits the northeastern Atlantic, from the British Isles to Senegal, and is the target of intense fishing activity. In the absence of previous genetic studies, we describe the genetic variability and structure of this species along Atlantic European coasts, paying special attention to the northwestern Iberian Peninsula (Galicia), where this species may be overexploited. Analysis of 2 mitochondrial fragments and 9 microsatellites indicates that these populations maintain appreciable levels of genetic diversity, most of which are found within localities. This scenario could be explained by quite large effective population sizes and noticeable levels of gene flow. M. brachydactyla in the northeastern Atlantic do not show any signs of a genetic bottleneck, and effectively conform to a diverse metapopulation with limited structure. KEY WORDS: Genetic diversity · Gene flow · Effective population size · MtDNA · Microsatellites · Crab population genetics · Phylogeography Full text in pdf format Supplementary appendix PreviousNextCite this article as: Sotelo G, Morán P, Fernández L, Posada D (2008) Genetic variation of the spiny spider crab Maja brachydactyla in the northeastern Atlantic. Mar Ecol Prog Ser 362:211-223. https://doi.org/10.3354/meps07433Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 362. Online publication date: June 30, 2008 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2008 Inter-Research.