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Mn-based oxides are promising for the selective catalytic reduction (SCR) of NOx with NH 3 at temperatures below 200 °C. There is a general agreement that combining Mn with another metal oxide, such as CeOx improves catalytic activity. However, to date, there is an unsettling debate on the effect of Ce. To solve this, here we have systematically investigated a large number of catalysts. Our results show that, at low-temperature, the intrinsic SCR activity of the Mn active sites is not positively affected by Ce species in intimate contact. To confirm our findings, activities reported in literature were surface-area normalized and the analysis do not support an increase in activity by Ce addition. Therefore, we can unequivocally conclude that the beneficial effect of Ce is textural. Besides, addition of Ce suppresses second-step oxidation reactions and thus N 2 O formation by structurally diluting MnOx. Therefore, Ce is still an interesting catalyst additive. The role of Ce one Mn-based catalysts for the selective catalytic reduction of NOx at low temperature is an ongoing debate. Here the authors demonstrate that Ce has a structural promoting effect but impacts negatively on the intrinsic catalytic activity of Mn.

This work was supported by the strategic programme UID/BIA/04050/2019 funded by Portuguese fundsthrough the FCT I.P., and the projects: PTDC/BIAMIC/5184/2014, funded by national funds through the Fundacao para a Ciencia e Tecnologia (FCT) I.P. and by the European Regional Development Fund (ERDF) through the COMPETE 2020-Programa Operacional Competitividade e Internacionalizacao (POCI), and EcoAgriFood: Innovative green products and processes to promote AgriFood BioEconomy (operacao NORTE-01-0145-FEDER-000009), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). DR acknowledges FCT for the SFRH/BD/96166/2013 PhD grant. MSS acknowledges the Norte2020 for the UMINHO/BD/25/2016 PhD grant with the reference NORTE-08-5369-FSE-000060. TR acknowledges Yeastdoc European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 764927.

The limited availability of antivirals for new highly pathogenic strains of virus has become a serious public health. Therefore, news products against these pathogens has become an urgent necessity. Among the multiple sources for news antibiotics and antivirals, insect exudates or their products has become an increasingly frequent option. Insects emerged 350 million years ago and have showed a high adaptability and resistance to the most varied biomes. Their survival for so long, in such different environments, is an indication that they have a very efficient protection against environmental infections, despite not having a developed immune system like mammals. Since the ancient civilizations, the products obtained from the bee have been of great pharmacological importance, being used as antimicrobial, anti-inflammatory, antitumor and several other functions. Investigations of biological activity of propolis have been carried out, mainly in the species Apis mellifera , and its product have showed activity against some important viruses. However, for the Meliponini species, known as stingless bees, there are few studies, either on their chemical composition or on their biological activities. The importance of studying these bees is because they come from regions with native forests, and therefore with many species of plants not yet studied, in addition to which they are regions still free of pesticides, which guarantees a greater fidelity of the obtained data. Previous studies by our group with crude hydroalcoholic extract of propolis demonstrated an intense antiviral activity against Herpes, influenza, and rubella viruses. In this work, we chose to use aqueous extracts, which eliminates the presence of other compounds besides those originally present in propolis, in addition to extracting substances different from those obtained in alcoholic extracts. Therefore, this study aimed to identify, isolate and characterize compounds with antiviral effects from aqueous propolis extracts from Scaptotrigona aff postica , in emerging viruses such as zicavirus, chikungunya, and mayaro virus. The evaluation of the antiviral activity of the crude and purified material was performed by reducing infectious foci in VERO cell cultures. The results obtained with crude propolis, indicate a high reduction of zica virus (64×) and mayaro (128×) when was used 10% v/v of propolis. The reduction of chikungunya virus was of 256 fold, even when was used 5% v/v of propolis. The chemical characterization of the compounds present in the extracts was performed by high-pressure liquid chromatography. Through the purification of propolis by HPLC and mass spectrometry, it was possible to identify and isolate a peak with antiviral activity. This substance showed activity against all viruses tested. When purified fraction was used, the reduction observed was of 16 fold for zicavirus, 32 fold for mayaro virus and 512 fold for chikungunya virus. Likewise, it was observed that the antiviral response was concentration dependent, being more intense when propolis was added 2 h after the viral infection. Now we are carrying out the chemical characterization of the purified compounds that showed antiviral action.

Secondary metabolites have been recognized for centuries as medicinal agents, in particular monoterpenes which have been the target of research in the discovery of antineoplastic drugs, as they have potential antitumor effect and low toxicity and are used as additives in foods and cosmetics. Another advantage of monoterpenes is structural diversity, which gives greater plasticity when interacting with cells. The purpose of this review was to summarize and critically discuss the anticancer potential of monoterpenes and their respective mechanisms of action. A systematic review of articles in the MEDLINE/PubMed, Web of Science, Scopus and Science Direct electronic databases was independently conducted by three reviewers using the combination of the following keywords: monoterpenes AND anticancer AND in vitro. Restriction in selecting articles followed pre-established inclusion and exclusion criteria by the reviewers, and also a time limitation with works published between 2015 and 2019 being selected. In total, 39 works were deemed eligible for inclusion in the final review. Monoterpenes have cytotoxic activity in a wide variety of tumor cell lines, and mainly appear to exert this effect by inducing apoptosis caused by oxidative stress. In addition, improved use of monoterpenes when used in drug delivery systems and the synergistic effect with conventional chemotherapeutic drugs are reported. These findings validate this class of compounds as a promising source of chemotherapeutic drugs yet to be explored.

Cellulose-based materials have been extensively investigated due to their abundance, renewable nature, and low abrasiveness and density. Cellulose nanocrystals (CNCs) stand out as nanometric particles of increasing technological interest, and also due to their potential use as nano-reinforcements to polymer composites. Since the effect of ultrasonic treatment on the structure and properties of CNCs is not yet fully understood, in this study the effect of ultrasonic output and hydrolysis time on yield and morphological, structural, and thermal properties of nanocrystals from microcrystalline cellulose (MCC) was studied. CNCs were prepared by conventional hydrolysis and compared to sonochemical extraction using 64 vol% H2SO4 at 45 °C. Sonication power varied from 50, 70 and 90%, and for each value a kinetic study was performed as a function of hydrolysis time until a colloidal gel suspension was obtained. Results showed that it was possible to obtain CNCs from MCC with reduced extraction time, whose thermal stability, aspect ratio and crystallinity index are comparable to those obtained by conventional acid hydrolysis. The ultrasound power intensity was the most important parameter to increase CNC sonochemical extraction productivity. The optimal CNC yield occurred at predetermined hydrolysis time intervals for each set of variables of low-intensity ultrasound-assisted hydrolysis. The disaggregation of freshly produced CNCs from MCC particles occurred simultaneously to size reduction of previously produced CNCs and conversion of amorphous phase into sugars. Due to the non-selective nature of sonochemical hydrolysis, it was proposed that hydrolysis proceeds regardless of the size and crystallinity degree of cellulose particles dispersed in the acidic medium. Therefore, there was an optimal hydrolysis time as a function of CNC yield for each set of hydrolysis parameters, since prolonged extraction times leaded to deterioration of the morphological and structural properties of CNCs.

Abstract Low density sugarcane plantation (LDSP) has been implemented by some sugarcane producers in Brazil, aiming to save seeds and operational costs. The study was carried out in the municipality of Areia, Paraíba, Brazil. Five planting densities were used, varying from 5 to 25 m-2 of buds arranged in randomized blocks, with four replications. Data were measured annually over three cultivation cycles (2017 to 2020), during which the field was fertilized with NPK and the harvests were carried out manually without prior burning. The lower planting density presents higher productivity only in the cane plant (101.03 t ha-1) due to the higher plant height (2.37 m) and the higher number of stalks (11 stalks m-2), suggesting that these variables are due to the greater availability of light, water and photosynthate. However, there is a drastic reduction in sugarcane yield for this lower population in the 2nd ratoon by up to 65.62%, which is correlated with number of stalks per meter. We demonstrate the agronomic viability of LDSP in the population of 10 buds m-2 in relation to conventional planting of sugarcane until the 2nd ratoon. Data are important for future studies to present additional considerations for other production factors, such as the effects of mechanized harvesting and the management of nutrients and water, assessing the sustainability of this large-scale planting system. Resumo O método de plantio de cana-de-açúcar de baixa densidade (LDSP) vem sendo implementado por alguns produtores de cana-de-açúcar no Brasil, visando economia de sementes e custos operacionais. O estudo foi realizado no município de Areia, Paraíba, Brasil. Utilizou-se cinco densidades de plantio, variando de 5 a 25 m-2 de gemas dispostas em blocos casualizados, com quatro repetições. Os dados foram medidos anualmente ao longo de três ciclos de cultivo (2017 a 2020). Menor densidade de plantio mostrou maior produtividade (101,03 t ha-1) devido à maior altura de planta (2,37 m) e ao maior número de hastes (NS) (11 hastes m-2), sugerindo que essas variáveis são devido à maior disponibilidade de luz, água e fotoassimilados. No entanto, houve redução drástica na produtividade da cana-de-açúcar para esta população menor na 2ª soca em 65,62%, estando correlacionado com o número de colmos por metro. Demonstramos a viabilidade agronômica do LDSP em uma população de 10 gemas m-2 em relação ao plantio convencional de cana-de-açúcar até a 2ª soca. Os dados são importantes para que estudos futuros apresentem considerações adicionais sobre outros fatores de produção, como os efeitos da colheita mecanizada e do manejo de nutrientes e água, avaliando a sustentabilidade desse sistema de plantio em larga escala.

Background Vaccine hesitancy is a concerning menace to the control of vaccine-preventable diseases. Effective health communication could promote an overall understanding of the importance, risks, and benefits of vaccination and reduce vaccine hesitancy. Methods In this survey, four fictitious newspaper articles addressing an emerging bogus disease and its vaccine were randomly assigned to participants. The first version focused on information about the disease; the second was akin to the first, including a case description and image. The third version focused on vaccine safety/efficacy; the fourth version was like the third, including a case description and image. After reading a single version of the article, participants responded if they would take the vaccine and if they would vaccinate their children. We used chi-squared tests for comparisons and investigated interactions with vaccine-hesitant attitudes. Results We included 5233 participants between August/2021 and January/2022; 790 were caregivers of a child ≤ 5 years old, and 15% had prior vaccine hesitancy. Although most declared intention to take the vaccine, the percentage was highest among those exposed to the newspaper article focusing on the vaccine safety/efficacy with the case description and picture (91%; 95% confidence interval 89–92%), and lowest among participants exposed to the article focusing on the disease with no case description (84%; 95% confidence interval 82–86%). Similar trends were observed in the intention of offspring vaccination. We found evidence of effect modification by vaccine-hesitant attitudes, with a higher impact of communication focusing on vaccine safety/efficacy compared to that focusing on disease characteristics among hesitant participants. Conclusion Communication strategies focusing on different aspects of the disease-vaccine duet may impact vaccine hesitancy, and storytelling/emotive imagery descriptions may improve risk perception and vaccine uptake. Moreover, the effect of message framing strategies may differ according to previous vaccine hesitant attitudes.

Background Despite the unequivocal benefits of vaccination, vaccine coverage has been falling in several countries in the past few years. Studies suggest that vaccine hesitancy is an increasingly significant phenomenon affecting adherence to vaccines. More recently, during the COVID-19 pandemic, political views have emerged as an additional influencing factor for vaccine hesitancy. Methods In this ecologic study, we used information from publicly available databases to investigate the association between political ideology, depicted by the percentage of votes for the right-wing candidate Jair Bolsonaro in the presidential elections of 2018 and 2022, and COVID-19 vaccination in Brazilian municipalities. The primary endpoint was the COVID-19 vaccination index, calculated as the number of COVID-19 vaccine doses administered up to September 2022 divided by the number of inhabitants in each municipality. The analysis was conducted using Pearson correlation coefficients and linear regression models adjusted for HDI, the percentage of male voters, the percentage of voters who were older than 50 years old, and the percentage of voters with a middle school education or less. In addition, we explored whether the effect of the percentage of Bolsonaro voters on the COVID-19 vaccination index was modified in different quartiles of HDI using an interaction term. Results Five thousand five hundred sixty-three Brazilian municipalities were included in the analysis. For both the 2018 and 2022 elections, the percentage of votes for Jair Bolsonaro was significantly and inversely associated with COVID-19 vaccine uptake after adjustment for the sociodemographic characteristics of the voters (change in mean vaccination index in 2018 for each 1% increase in Bolsonaro voters -0.11, 95% confidence interval [CI] -0.13 to -0.08, p  < 0.001; change in mean vaccination index in 2022 for each 1% increase in Bolsonaro voters -0.09, 95% CI -0.11 to -0.07, p  < 0.001). We also found a statistically significant interaction between the primary predictor of interest and HDI scores, with a more significantly detrimental effect of the right-wing political stance in municipalities in the lower HDI quartiles (interaction p  < 0.001 for the first HDI quartile; p  = 0.001 for the second HDI quartile). Conclusion Our findings suggest that political ideologies have influenced COVID-19 vaccine hesitancy in Brazilian municipalities, affecting communities inequitably. The politicization of vaccines is a new challenge for vaccine programs. Strategies to face these challenges should include joint efforts from governments and civil society for a common public health goal.

In this open-label, randomized trial in patients newly receiving mechanical ventilatory support for Covid-19–associated ARDS, those who received convalescent plasma had lower 28-day mortality than those who received standard care.