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Abstract: Nanocrystalline Ca1−x Sm x MnO3 (0≤ x ≤0.4) manganites were prepared by a soft chemical method (Pechini method) followed by auto-combustion and sintering in air at 1073 or 1473K. Single-phase powders with general composition Ca1−x Sm x MnO3 were obtained after 18h annealing. The particle and grain sizes of the substituted Sm-manganites did not exhibit variation with samarium content, but increase with increasing the sintering temperature. All manganites show two active IR vibrational modes near 400 and 600cm−1 characteristic of the BO6 octahedron vibrations. For the samples sintered at T s =1473K, the partial substitution of calcium by samarium in the CaMnO3 phase induces a marked decrease in the electrical resistivity, in the temperature range of 300–900K, and at the same time a metal-to-insulator transition occurs; for T s =1073K all the samples present semiconductor behaviour. With the increase of the annealing temperature the grain size increases and a metal–semiconductor transition appears. The results can be ascribed to the Mn4+/Mn3+ ratio and particle grain size. The effects of particle size on the electrical properties can be attributed to the domain status, changes in the Mn–O–Mn bond angle and Mn–O bond length. [Copyright &y& Elsevier]

Background: Migrants in high-income countries (HICs) may have been disproportionately affected by the COVID-19 pandemic, yet the extent to which they are impacted, and their predisposing risk factors, are not clearly understood. We did a systematic review to assess clinical outcomes, indirect health and social impacts, and key risk factors in migrants. Methods: Our systematic review following PRISMA guidelines (PROSPERO CRD42020222135) identified peer-reviewed and grey literature relating to migrants (foreign-born) and COVID-19 in 82 HICs. Primary outcomes were cases, hospitalisations and deaths from COVID-19 involving migrants; secondary outcomes were indirect health and social impacts and risk factors. Results: 3016 data sources were screened with 158 from 15 countries included in the analysis. We found migrants are at increased risk of SARS-CoV-2 infection and are over-represented among cases (e.g. constituting 42% of cases in Norway [to 27/4/2020], 26% in Denmark [to 7/9/2020], and 32% in Sweden [to 7/5/ 2020]); some datasets from Europe show migrants may be over-represented in deaths with increased all-cause mortality in migrants in some countries in 2020. Undocumented migrants, migrant health and care workers, and migrants housed in camps have been especially affected, with certain nationality groups disproportionately impacted. Migrants experience a range of risk factors for COVID-19, including high-risk occupations, overcrowded accommodation, and barriers to healthcare including inadequate information, language barriers, and reduced entitlement. Conclusions: Migrants in HICs are at high risk of COVID-19, with a range of specific risk factors that have not been well-considered in the public health response to date. These data are of immediate relevance to the policy response to the pandemic, with strategies urgently needed to reduce transmission. Migrant populations must also be better considered in national plans for COVID-19 vaccination roll-out. On behalf of ESGITM Key messages: • Migrants in high-income countries may be disproportionately represented in COVID-19 infections and deaths, with higher levels of many vulnerabilities and risk factors. • Migrants must be better included in all aspects of the pandemic response, including vaccination roll-out. [ABSTRACT FROM AUTHOR]

Abstract Background Squalius alburnoides is an Iberian cyprinid fish resulting from an interspecific hybridisation between Squalius pyrenaicus females (P genome) and males of an unknown Anaecypris hispanica-like species (A genome). S. alburnoides is an allopolyploid hybridogenetic complex, which makes it a likely candidate for ploidy mosaicism occurrence, and is also an interesting model to address questions about gene expression regulation and genomic interactions. Indeed, it was previously suggested that in S. alburnoides triploids (PAA composition) silencing of one of the three alleles (mainly of the P allele) occurs. However, not a whole haplome is inactivated but a more or less random inactivation of alleles varying between individuals and even between organs of the same fish was seen. In this work we intended to correlate expression differences between individuals and/or between organs to the occurrence of mosaicism, evaluating if mosaics could explain previous observations and its impact on the assessment of gene expression patterns. Results To achieve our goal, we developed flow cytometry and cell sorting protocols for this system generating more homogenous cellular and transcriptional samples. With this set-up we detected 10% ploidy mosaicism within the S. alburnoides complex, and determined the allelic expression profiles of ubiquitously expressed genes (rpl8; gapdh and β-actin) in cells from liver and kidney of mosaic and non-mosaic individuals coming from different rivers over a wide geographic range. Conclusions Ploidy mosaicism occurs sporadically within the S. alburnoides complex, but in a frequency significantly higher than reported for other organisms. Moreover, we could exclude the influence of this phenomenon on the detection of variable allelic expression profiles of ubiquitously expressed genes (rpl8; gapdh and β-actin) in cells from liver and kidney of triploid individuals. Finally, we determined that the expression patterns previously detected only in a narrow geographic range is not a local restricted phenomenon but is pervasive in rivers where S. pyrenaicus is sympatric with S. alburnoides. We discuss mechanisms that could lead to the formation of mosaic S. alburnoides and hypothesise about a relaxation of the mechanisms that impose a tight control over mitosis and ploidy control in mixoploids.

Abstract Background The genetic contribution to stroke is well established but it has proven difficult to identify the genes and the disease-associated alleles mediating this effect, possibly because only nuclear genes have been intensely investigated so far. Mitochondrial DNA (mtDNA) has been implicated in several disorders having stroke as one of its clinical manifestations. The aim of this case-control study was to assess the contribution of mtDNA polymorphisms and haplogroups to ischemic stroke risk. Methods We genotyped 19 mtDNA single nucleotide polymorphisms (SNPs) defining the major European haplogroups in 534 ischemic stroke patients and 499 controls collected in Portugal, and tested their allelic and haplogroup association with ischemic stroke risk. Results Haplogroup H1 was found to be significantly less frequent in stroke patients than in controls (OR = 0.61, 95% CI = 0.45–0.83, p = 0.001), when comparing each clade against all other haplogroups pooled together. Conversely, the pre-HV/HV and U mtDNA lineages emerge as potential genetic factors conferring risk for stroke (OR = 3.14, 95% CI = 1.41–7.01, p = 0.003, and OR = 2.87, 95% CI = 1.13–7.28, p = 0.021, respectively). SNPs m.3010G>A, m.7028C>T and m.11719G>A strongly influence ischemic stroke risk, their allelic state in haplogroup H1 corroborating its protective effect. Conclusion Our data suggests that mitochondrial haplogroup H1 has an impact on ischemic stroke risk in a Portuguese sample.

The classical development of drugs has progressively faded away, and we are currently in an era of seamless drug-development, where first-in-human trials include unusually big expansion cohorts in the search for early signs of activity and rapid regulatory approval. The fierce competition between different pharmaceutical companies and the hype for immune combinations obliges us to question the current way in which we are evaluating these drugs. In this review, we discuss critical issues and caveats in immunotherapy development. A particular emphasis is put on the limitations of pre-clinical toxicology studies, where both murine models and cynomolgus monkeys have underpredicted toxicity in humans. Moreover, relevant issues surrounding dose determination during phase I trials, such as dose–escalation methods or flat versus body-weight dosing, are discussed. A proposal of how to face these different challenges is offered, in order to achieve maximum efficacy with minimum toxicity for our patients. [ABSTRACT FROM AUTHOR]

Introducción: En la actualidad la obesidad y el sobrepeso son un importante problema de salud para los niños y adolescentes en los países desarrollados y también en Cuba. Objetivo: Determinar algunos factores de riesgo asociados en adolescentes con malnutrición por exceso del Policlínico Julio Grave de Peralta de la provincia Holguín (Cuba) durante el periodo de agosto del 2011 a Febrero del 2012. Método: Se realizó un estudio analítico transversal. Se estudiaron 37 adolescentes entre 15-19 años. Variables incluidas: sexo, evaluación nutricional, presión arterial, colesterol total y triglicéridos. Para el análisis comparativo se empleó el test de Chi cuadrado. En todos los casos, se trabajó con un nivel de significación de p < 0,05. Resultados: Se encontró obesidad en el 24,32% de los adolescentes y fue más frecuente en el sexo femenino. En el grupo de pacientes con malnutrición por exceso 12 presentaron antecedentes patológicos familiares de obesidad (80,0%), X² = 13,87. Los adolescentes con malnutrición por exceso tuvieron altos niveles de colesterol y triglicéridos. El 20,0% de los adolescentes con malnutrición por exceso presentó Hipertensión Grado I. Se encontró asociación significativa entre la malnutrición por exceso y los niveles elevados de colesterol y triglicéridos. Conclusiones: Los antecedentes patológicos familiares de obesidad, los niveles altos de colesterol y triglicéridos y las cifras tensionales elevadas resultaron factores de riesgo asociados a la malnutrición por exceso en los adolescentes. [ABSTRACT FROM AUTHOR]

Abstract: Silica-occluded tungstophosphoric acid (PW-Ssg) was used as an efficient, environmentally friendly heterogeneous catalyst for the liquid-phase alkoxylation of camphene into their more valuable alkyl isobornyl ether, which is used as perfume and cosmetic products, in the pharmaceutical industry, as well as in the food industry. The alkoxylation of camphene with C1–C4 alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-butanol) to alkyl isobornyl ether was studied in the presence of PW-Ssg (4.2% w/w) at 60–80°C. Different linear and branched alcohols are compared in relation to their activity for the alkoxylation of camphene. The catalytic activity decreased with the increase of number of carbon atoms in the chain alcohol, which can be explained due to the presence of sterical hindrance and diffusion limitations inside the porous system of the catalyst. High selectivity of PW-Ssg catalyst for the alkyl isobornyl ether was observed. The effect of various parameters, such as catalysts loading, initial concentration of camphene and temperature were studied to optimise the ethoxylation of camphene. The catalytic stability of PW-Ssg in the ethoxylation of camphene was studied by performing consecutive batch runs with the same catalyst sample at the same conditions. After the third run, the catalytic activity stabilized. The catalyst can be recovered and reused without significant leaching of PW. The catalytic activity of PW-Ssg was compared with the activity of tungstophosphoric acid immobilized on silica by impregnation method (PW-Sim). The activity of PW-Ssg is higher than that of PW-Sim catalyst. After reaction, the PW-Sim sample lost 20% of its heteropolyacid. [Copyright &y& Elsevier]

Abstract: An activated carbon Norit RX3 has been treated with acids (sulphuric, nitric and sulphonitric mixture). The modified activated carbons have been characterized by elemental analysis, point of zero charge, N2 adsorption, XPS and FTIR. The solids obtained have been used as acidic heterogeneous catalyst in the reaction between imidazole and haloalkanes. The reaction with 1-bromobutane yields an ionic liquid, N,N-di-n-butyl-imidazolium bromide (1). Reaction with 2-bromobutane and 1-chlorohexane yields the corresponding N-alkyl-imidazoles (2) and (3). Sulphuric acid treated carbon is the most active catalyst. [Copyright &y& Elsevier]

A point q is embraced by a set of points S if q is interior to the convex hull of S []. In some illumination applications where points of S are lights and q is a point to be illuminated, the embracing concept is related to a good illumination [, ], also known as the ∆-guarding [] and the well-covering []. In this paper, we are not only interested in convex dependency (which is actually the embracing notion) but also in proximity. Suppose that the sites of S are lights or antennas with limited range; due to their limited power, they cover a disk of a given radius r centered at the sites of S. Only the points lying in such disks are illuminated. If we want to embrace the point q with the minimum range r, we need to know which is the closest light s q to q such that q lies in the convex hull formed by s q and the lights of S closer to q than s q. This subset of S related to point q is called the closest embracing set for q in relation to S and its cardinality is the closest embracing number of q. By assigning every point q in the convex hull of S to its closest embracing site s q, we obtain a partition of the convex hull that we call the embracing Voronoi diagram of S. This paper proves some properties of the embracing Voronoi diagrams and describes algorithms to compute such diagrams, as well as the levels in which the convex hull is decomposed regarding the closest embracing number. [ABSTRACT FROM AUTHOR]

Abstract: A systematic study of the A-site doping in Mn(IV)-rich perovskite manganites Ca1−x Ho x MnO3, over a large homogeneity range (0.1≤ x ≤0.4), has been performed. A significant increase in the lattice parameters indicated the presence of mixed valence state of Mn: Mn3+ and Mn4+. The substitution of calcium by holmium also induces strong changes in the electrical properties. We found that small Ho concentration produces an important decrease in the electrical resistivity and induces an electrical transition, the temperature corresponding to the metal–insulator transition (T MI) shifts with the holmium content. This electrical behavior is attributed to the Mn3+ ions content and a charge order effect. [Copyright &y& Elsevier]

Background: Migrants in Europe are at risk of under-immunisation and may also have lower COVID-19 vaccination intent and uptake. There is an urgent need to better understand the drivers of uptake in these groups to inform the development of migrantsensitive interventions for COVID-19 vaccination and routine vaccination beyond the pandemic. Methods: We did a systematic review (PROSPERO: CRD42020219214) following PRISMA guidelines to explore factors influencing vaccine uptake in migrants in the EU/EEA and identify determinants of under-immunisation. We also held 3 participatory workshops with multinational migrant community leaders (n = 23) in London, to explore solutions and approaches to strengthen COVID-19 vaccine roll-out. Results: We included 66 papers reporting data on 262,761 migrants in the review. Numerous access-related factors (e.g. government policy, communication barriers) influenced uptake. Vaccine hesitancy was attributed to lack of information, concerns [ABSTRACT FROM AUTHOR]