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Rice husk is considered as a waste in the rice industry but is proficient in manufacturing different materials, such as zeolites, which is produced in large quantities all over the world, for example in Brazil. Zeolite is an adsorbent support material, which can be synthesized from rice husk ash (RHA) with external sources of aluminium (ESA). The scientific community has been conducting several measures to minimize the environmental impacts caused by greenhouse gases. Several mitigation processes are presently investigated, which includes carbon dioxide injections into adsorbent materials (e.g. zeolites). The efficiency of this technology involves a zeolitic material with high crystallinity and high concentrations of SiO2 and Al2O3 (aluminosilicates). In the present work, zeolites have been synthesized from rice husk ash (SiO2 source) and external aluminium sources (Al2O3 - alumina, gibbsite and metakaolin) to fulfill that purpose. With the aid of XRF, XRD, SEM/EDS and FTIR techniques, the zeolitic material was characterized in two distinct crystalline phases: Mordenite and ZSM-5. The synthesis was carried out by the ideal addition of ESA (2.5 g) to RHA. According to the literature, the zeolitic materials formed by the mixture of Mordenite and ZSM-5 can be availed for gas separation and greenhouse gas storage.

Mordenite zeolite is considered a molecular sieve because of its adsorbent material characteristics used in the industry as a gas separator. High Si/Al ratios of this zeolitic material in its crystal lattice provide high thermal stability in the structure. To minimize the production costs, this work synthesized the mordenite zeolite in absence organic template (high costs of production). For this purpose, rice husk ash (silicon source) was used from a thermoelectric plant that uses biomass for power generation under the “Moving Grade Reactor” method and metakaolin (aluminium source) derived from the construction. To obtain the zeolitic material, an alkaline treatment with sodium hydroxide and deionized water was required. Different Si/Al ratios (5, 10, 15, and 20) were used to evaluate the highest efficiency in adsorption capacity. The textural properties of mordenite as a function of specific surface area ranged from 314 to 347 m 2 /g, with micropore volume 0.198–0.279 cm 3 /g with average pore diameter ranging from 5.9 to 6.2 Å. N 2 adsorption/desorption isotherms obtained for mordenite presented type IV hysteresis, characteristic of microporous materials. X-ray diffraction showed crystalline phases of mordenite zeolite, mostly. The FTIR reinforces the success of mordenite synthesis by the vibration bands corresponding to the zeolitic material. TGA revealed water desorption and absence of an organic director. The mean cation-exchange capacity values ranged from 1.10 to 1.78 meq/g indicating a 62% increase of 20-mordenite zeolite compared to 5-mordenite in the zeolitization process. This result is satisfactory and promising for the use of mordenite as adsorbent material.

The textile industries release a substantial amount of effluents into water resources every year. The vast majority of these effluents are composed of heavy metals that bind the textile fibres with dyes. This work proposes to use an adsorption system composed of clay-minerals (kaolinite and montmorillonite) and molecular sieve (zeolite) for separating the Cu 2+ and Cr 6+ ions, considering the pH changes of aqueous solutions. The adsorbent materials were characterized using the following state of the art techniques such as X-ray fluorescence, X-ray diffraction, Raman spectroscopy and Cation exchange capacity. During the adsorption tests, the contact time of the adsorbates (Cu 2+ and Cr 6+ ions in concentrations of 100, 50, 10 and 5 mg/L) with the adsorbents vary from 1 to 4 h in acidic and alkaline conditions (pH 3.5 and 7.5). The results indicate maximum adsorption of Cu 2+ (at pH 3.5) and Cr 6+ (at pH 7.5) ions on application of the zeolitic material. The clay minerals conclusively proved to be less efficient when compared to zeolite. It can be concluded that the adsorption system has achieved the desired efficiency, with substantial removal of Cu 2+ and Cr 6+ ions for zeolites in synthetic wastewater solutions of the textile industry.

New techniques for the use of renewable fuels have been proposed by researchers around the world, seeking to reduce our dependence on fossil fuels and emissions of harmful gases. For compression ignition engines, fumigation stands out for allowing more significant replacements than other dual-fuel techniques, and also for not requiring modifications to the original engine structure. In this context, wet ethanol has emerged as one of the most viable fuels for port fuel injection due to its low reactivity and its renewable origin. This paper investigates the effects caused on the compression ignition engine by the use of diesel oil and wet ethanol by fumigation method and an air restriction in the engine intake through a throttle. The used engine was a small single-cylinder, coupled to an alternator, with constant load and engine speed. The fumigation fuel was wet ethanol with four different water concentrations, and different fractions of diesel oil substitution were tested. The results indicated that the use of ethanol and wet ethanol by the fumigation method increases conversion efficiency by up to 10% compared to the baseline test. However, the reduction in the intake airflow always causes a decrease in this efficiency. Intake air throttled also provided an increase in exhaust gas opacity compared to the free airflow conditions, but it is reduced when compared to the baseline test. Concerning specific emissions, carbon monoxide has higher emission levels when ethanol fumigation is used compared to the baseline condition. Under the same conditions, nitrogen oxide emissions are reduced.

Este trabalho objetiva analisar as características das publicações sobre conforto térmico em salas de aula nas bases de dados Scopus e Web of Science (WOS), identificando as principais fontes, os principais autores e algumas particularidades sobre a produção científica deste tema. O estudo compreende uma revisão bibliográfica que foi realizada a partir de uma pesquisa bibliométrica, na qual por meio de uma análise estatística foi possível mapear e gerar alguns indicadores para o tratamento da informação, constituindo assim, uma abordagem quantitativa e qualitativa. Na base Scopus, foram encontradas 231 publicações relacionadas e na WOS, 135 publicações. Os resultados comparativos mostraram que o número de trabalhos relacionados ao conforto térmico em salas de aula aumentou consideravelmente na última década. Verificou-se que a China é o país com o maior número de publicações. O Brasil surge na 12ª posição na base Scopus e na 10ª posição na base WOS. Também verificou-se a importância do periódico Building and Environment para o tema e que para as salas de aula e ambientes de estudo, há uma estreita relação entre os tópicos conforto térmico, ventilação e qualidade do ar interno, uma vez que estes podem interferir consideravelmente no rendimento e na saúde dos alunos.

Diagenetic alteration in the Eocene turbidite reservoirs of Espírito Santo Basin has been envisaged through geochemical modeling using TOUGHREACT software. Extensive albitization has been encountered, accompanied by the dissolution of detrital plagioclase and K‐feldspars. The diapiric impregnation of the succession by halokinesis and the resulting high salinity of pore water suggest that diagenesis was invigorated by the entry of brine from the salt diapirs. The circulation of high‐temperature fluids from the diapirs through fractures is the main cause of the late diagenetic reactions, thereby influencing the reservoir quality. This behavior is accompanied by concomitantly growing authigenic quartz crystals as derived from the fluid‐inclusion study. Based on the available geological and geochemical data, a series of computer simulations present the effects of fluid percolating through the reservoir and non‐reservoir depositional elements deposited from sediment‐gravity flows, along with the influence of this interaction with the salt domes. The simulations were carried out in batch mode to stabilize the water with sandstone and the results were then utilized in a series of 1D simulations. A nominal water flow of 10 cm y −1 was assumed in isothermal conditions at 100 °C. In this scenario, the precipitation of calcite in sandstone was considered to occur due to the presence of thermobaric flow. Its authigenic precipitation is strongly controlled by the dissolution of plagioclase. The simulations carried out with TOUGHREACT reveal the potential of the simulator to model the complex diagenetic cases of turbiditic reservoirs in an analog stratigraphic configuration. The simulations also demonstrate the need to dynamically integrate the diagenesis associated with the sandstones so that the obtained results can be consistent with the real diagenetic patterns.

Garcinia is a genus of Clusiaceae, distributed throughout tropical Asia, Africa, New Caledonia, Polynesia, and Brazil. Garcinia plants contain a broad range of biologically active metabolites which, in the last few decades, have received considerable attention due to the chemical compositions of their extracts, with compounds which have been shown to have beneficial effects in several diseases. Our work had the objective of reviewing the benefits of five Garcinia species (G. brasiliensis, G. gardneriana, G. pedunculata, G. cambogia, and G. mangstana). These species provide a rich natural source of bioactive compounds with relevant therapeutic properties and anti-inflammatory effects, such as for the treatment of skin disorders, wounds, pain, and infections, having demonstrated antinociceptive, antioxidant, antitumoral, antifungal, anticancer, antihistaminic, antiulcerogenic, antimicrobial, antiviral, vasodilator, hypolipidemic, hepatoprotective, nephroprotective, and cardioprotective properties. This demonstrates the relevance of the genus as a rich source of compounds with valuable therapeutic properties, with potential use in the prevention and treatment of nontransmissible chronic diseases.

The study of medicinal plants, such as the genus Garcinia (Clusiaceae), in the treatment of non-communicable chronic diseases has aroused the interest of researchers. However, there are no studies in the literature that have investigated the effects of Garcinia gardneriana in experimental models of obesity for possible metabolic alterations. Swiss mice receiving a high-fat diet were supplemented with aqueous or ethanolic extract of G. gardneriana at doses of 200 or 400 mg/kg/day. It was found that there was a reduction in food consumption in experimental groups compared with the control groups, and the group supplemented with aqueous extract at a dose of 200 mg/kg/daydisplayed a reduction in weight. The results showed an increase in the values of high density lipoprotein (HDL-c), total cholesterol, triglycerides and fasting blood glucose. G. gardneriana did not protect against insulin resistance, and caused in an increase in monocyte chemoattractant protein-1 (MCP-1) concentrations and a reduction in interleukin 10 (IL-10). In addition, hepatic steatosis and microvesicular steatosis were indicated. It was revealed that, under the experimental conditions in the study, G. gardneriana did not prevent weight gain or comorbidities; that is, a different behavior was obtained from that described in the literature with regard to the medicinal potential of the Garcinia species, which is probably related to the phytochemical properties.

Vaccines are essential for the prevention and control of several diseases, and monitoring the immune response generated by vaccines is crucial. The immune response generated by vaccination against SARS-CoV-2 in children and adolescents is not well defined in terms of the intensity and medium to long-term duration of protective immunity, which may indicate the need for booster doses and could support decisions in public health. The study aims to evaluate the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine (CoronaVac) in a two-dose primary protocol in children and adolescents aged 3 to 17 years old in Brazil. Participants were invited to the research at two public healthcare centers located in Serrana (São Paulo) and Belo Horizonte (Minas Gerais), Brazil. They underwent medical interviews to gather their medical history, including COVID-19 history and medical records. Physical exams were conducted, which included measurements of weight, blood pressure, temperature, and pulse rate. Blood samples were obtained from the participants before vaccination, 1 month after the first dose, and at 1, 3, and 6 months after the second dose. These samples were followed up using a virtual platform to monitor post-vaccination reactions and symptoms of COVID-19. The SARS-CoV-2 genome from swab samples of COVID-19 positive individuals was sequenced using NGS. Total antibodies were measured by ELISA, and neutralizing antibodies to the B.1 lineage and Omicron variant (BA.1) were quantified by PRNT and VNT assays. The cellular immune response was evaluated by flow cytometry through the quantification of systemic soluble immune mediators. The follow-up of 640 participants showed that CoronaVac was able to significantly induce the production of total IgG antibodies to SARS-CoV-2 and the production of neutralizing antibodies to the B.1 lineage and Omicron variant. Additionally, a robust cellular immune response was observed, characterized by a wide release of pro-inflammatory and regulatory mediators in the early post-immunization moments. Adverse events recorded so far have been mild and transient, except for seven serious adverse events reported on VigiMed. The results indicate a robust and sustained immune response induced by CoronaVac in children and adolescents for up to six months, providing evidence to support the safety and immunogenicity of this effective immunizer.

Objective To investigate characteristics that may be associated with radiologic and functional findings following discharge in patients with severe coronavirus disease 2019 (COVID-19). Methods This single-center, prospective, observational cohort study comprised patients aged >18 years who were hospitalized with COVID-19 pneumonia, between May and October 2020. After 3 to 6 months of discharge, patients were clinically evaluated and underwent spirometry, a 6-minute walk test (6MWT), and chest computed tomography (CT). Statistical analysis was performed using association and correlation tests. Results A total of 134 patients were included (25/114 [22%] were admitted with severe hypoxemia). On the follow-up chest CT, 29/92 (32%) had no abnormalities, regardless of the severity of the initial involvement, and the mean 6MWT distance was 447 m. Patients with desaturation on admission had an increased risk of remaining CT abnormalities: patients with SpO2 between 88 and 92% had a 4.0-fold risk, and those with SpO2 < 88% had a 6.2-fold risk. The group with SpO2 < 88% also walked shorter distances than patients with SpO2 between 88 and 92%. Conclusion Initial hypoxemia was found to be a good predictor of persistent radiological abnormalities in follow-up and was associated with low performance in 6MWT.