2,024 research outputs found
Evolutionary implications of microplastics for soil biota
This is the author accepted manuscript. The final version is available from CSIRO Publishing via the DOI in this recordMicroplastic pollution is increasingly considered to be a factor of global change: in addition to aquatic ecosystems, this persistent contaminant is also found in terrestrial systems and soils. Microplastics have been chiefly examined in soils in terms of the presence and potential effects on soil biota. Given the persistence and widespread distribution of microplastics, it is also important to consider potential evolutionary implications of the presence of microplastics in soil; we offer such a perspective for soil microbiota. We discuss the range of selection pressures likely to act upon soil microbes, highlight approaches for the study of evolutionary responses to microplastics, and present the obstacles to be overcome. Pondering the evolutionary consequences of microplastics in soils can yield new insights into the effects of this group of pollutants, including establishing ‘true’ baselines in soil ecology, and understanding future responses of soil microbial populations and communities.MR acknowledges support from the ERC Advanced Grant ‘Gradual Change’ (694368).
UK received funding from the European Union's Horizon 2020 research and innovation
program under Marie Skłodowska-Curie grant agreement no. 751699
An adaptive observer-based controller design for active damping of a DC network with a constant power load
This article explores a nonlinear, adaptive controller aimed at increasing the stability margin of a direct-current (dc), small-scale, electrical network containing an unknown constant power load (CPL). Due to its negative incremental impedance, this load reduces the effective damping of the network, which may lead to voltage oscillations and even to voltage collapse. To overcome this drawback, we consider the incorporation of a controlled dc-dc power converter in parallel with the CPL. The design of the control law for the converter is particularly challenging due to the existence of unmeasured states and unknown parameters. We propose a standard input-output linearization stage, to which a suitably tailored adaptive observer is added. The good performance of the controller is validated through experiments on a small-scale network
Iodine Availability through Iodized Salt in Portugal: 2010-2021 Sales Evolution and Distribution
Salt iodization programs are considered the most cost-effective measures to ensure adequate iodine intake in iodine-deficient populations. Portuguese women of childbearing age and pregnant women were reported to be iodine-deficient, which led the health authorities, in 2013, to issue a recommendation for iodine supplementation during preconception, pregnancy and lactation. In the same year, iodized salt became mandatory in school canteens. Of note, no regulation or specific programs targeting the general population, or the impact of iodized salt availability in retailers, are known. The present study analyzed iodized salt supermarket sales from 2010 to 2021 from a major retailer, identifying the proportion of iodized salt in total salt sales and its distribution in mainland Portugal. Data on iodine content were collected through the nutritional label information. Of a total of 33 salt products identified, 3 were iodized (9%). From 2010 to 2021, the weighted sales of iodized salt presented a growing tendency, reaching the maximum of 10.9% of total sales (coarse plus fine salt) in 2021. Iodized salt reached a maximum of 11.6% of total coarse salt in 2021, a maximum of 2.4% of the total fine salt in 2018. The overall sales of iodized salt and their contribution to iodine intake are extremely low, prompting additional studies to understand the consumer's choice and awareness of the benefits of iodized salt
Angiogenic effects of cryosurgery with liquid nitrogen on the normal skin of rats, through morphometric study
Fractional variational calculus of variable order
We study the fundamental problem of the calculus of variations with variable
order fractional operators. Fractional integrals are considered in the sense of
Riemann-Liouville while derivatives are of Caputo type.Comment: Submitted 26-Sept-2011; accepted 18-Oct-2011; withdrawn by the
authors 21-Dec-2011; resubmitted 27-Dec-2011; revised 20-March-2012; accepted
13-April-2012; to 'Advances in Harmonic Analysis and Operator Theory', The
Stefan Samko Anniversary Volume (Eds: A. Almeida, L. Castro, F.-O. Speck),
Operator Theory: Advances and Applications, Birkh\"auser Verlag
(http://www.springer.com/series/4850
Social interactions through the eyes of macaques and humans
Group-living primates frequently interact with each other to maintain social bonds as well as to compete for valuable resources. Observing such social interactions between group members provides individuals with essential information (e.g. on the fighting ability or altruistic attitude of group companions) to guide their social tactics and choice of social partners. This process requires individuals to selectively attend to the most informative content within a social scene. It is unclear how non-human primates allocate attention to social interactions in different contexts, and whether they share similar patterns of social attention to humans. Here we compared the gaze behaviour of rhesus macaques and humans when free-viewing the same set of naturalistic images. The images contained positive or negative social interactions between two conspecifics of different phylogenetic distance from the observer; i.e. affiliation or aggression exchanged by two humans, rhesus macaques, Barbary macaques, baboons or lions. Monkeys directed a variable amount of gaze at the two conspecific individuals in the images according to their roles in the interaction (i.e. giver or receiver of affiliation/aggression). Their gaze distribution to non-conspecific individuals was systematically varied according to the viewed species and the nature of interactions, suggesting a contribution of both prior experience and innate bias in guiding social attention. Furthermore, the monkeys’ gaze behavior was qualitatively similar to that of humans, especially when viewing negative interactions. Detailed analysis revealed that both species directed more gaze at the face than the body region when inspecting individuals, and attended more to the body region in negative than in positive social interactions. Our study suggests that monkeys and humans share a similar pattern of role-sensitive, species- and context-dependent social attention, implying a homologous cognitive mechanism of social attention between rhesus macaques and humans
Using an in-vitro biofilm model to assess the virulence potential of Bacterial Vaginosis or non-Bacterial Vaginosis Gardnerella vaginalis isolates
Gardnerella vaginalis is the most common species found in bacterial vaginosis (BV). However, it is also present in a significant proportion of healthy women and G. vaginalis vaginal colonization does not always lead to BV. In an effort to better understand the differences between G. vaginalis isolated from women with a positive (BV) versus a negative (non-BV) diagnosis of BV, we compared the virulence potential of 7 BV and 7 non-BV G. vaginalis isolates and assessed the virulence factors related to biofilm formation, namely: initial adhesion and cytotoxic effect, biofilm accumulation, susceptibility to antibiotics, and transcript levels of the known vaginolysin, and sialidase genes. Furthermore, we also determined the ability of G. vaginalis to displace lactobacilli previously adhered to HeLa cells. Our results showed that non-BV strains were less virulent than BV strains, as suggested by the lower cytotoxicity and initial adhesion to Hela cells. Significant differences in expression of known virulence genes were also detected, further suggesting a higher virulence potential of the BV associated G. vaginalis. Importantly, we demonstrated that BV associated G. vaginalis were able to displace pre-coated vaginal protective lactobacilli and we hypothesize this to be a trigger for BV development.European Union funds (FEDER/COMPETE)
and by national funds (FCT) under the project with reference FCOMP-01-0124-FEDER-008991 (PTDC/BIA-MIC/098228/2008). FCT Strategic Project of UID/BIO/04469/2013 unit the project NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte(ON.2 – O Novo Norte), QREN, FEDER, and the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462). FCT individual fellowship SFRH/BD/93963/2013
Safety and efficacy of maraviroc (MVC) combined with multiple different therapeutic agents in highly treatment-experienced (TE) patients in Brazil
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