Production and characterisation of amorphous silica from rice husk waste

Rice covers about 1% of the earth’s surface. Rice husk is the major by-product of the riceprocessing industries which must be appropriately managed. On average 20% of the rice paddy is husk. The major constituents of rice husk are cellulose, lignin and silica. During growth, rice plants absorb silica and other minerals from the soil and accumulate it into their structures. Its composition varies with the diversity, climate and geographic location of growth. The high grade of silica in the husk opens a possibility for its valorisation. Through thermal treatment by calcination, with or without energy recovery, the ash obtained is constituted by amorphous silica with high porosity having potential application as ligand in construction materials, catalyst support, metals adsorbent, insulation or ceramics, among others. In the research developed, the rice husk was processed by washing, acid leaching and calcination in order to produce an ash, which was characterized aiming at assessing possible valorising solutions. The chemical treatment involved water washing for partial purification of the husk, and leaching with diluted sulphuric acid solution, allowing obtaining high metals removal efficiency, decreasing at least 90% of the initial content of contaminants (K, Fe and Mn). After calcination at 540ºC for organics decomposition, the final ash consisted in white colour amorphous silica as confirmed by XRPD analysis, being characterized by SEM to evaluate the microstructure. The results showed that after calcination the rice husk ash had a very porous, alveolar and even tracery morphology, which seems promising for applications requiring high reactivity, such as in construction materials and technical ceramics

SURF ADAPTADO E PARASURF: UMA REVISÃO INTEGRATIVA

Adaptive Surf arises to corroborate to the diversity of physical activity practices in nature by enabling it to be carried out by people with any type of disability, such as physical, hearing, intellectual or other, in order to expand the range of inclusive possibilities and be one of the aspects of Adapted Physical Education. In this context, the aim of this study is to carry out a brief integrative review on adaptive surfing and parasurfing for people with disability and their development process at national and international levels, together with a literature review. Therefore, the study is characterized as a narrative research, with a qualitative approach. From the analysis of the data, it was possible to observe that there is a literary scarcity regarding the theme, however, in recent years there has been a greater incidence of the modality’s dissemination, which, even little in the academic environment, has been rising over both parasports practices, whether for recreation or for high performance purposes.O Surf Adaptado surge para corroborar a diversidade das práticas de atividades físicas da natureza ao possibilitar a sua realização por pessoas com quaisquer tipo de deficiência, seja física, auditiva, intelectual ou outra, de modo a ampliar a gama de possibilidades inclusivas e ser uma das vertentes para a Educação Física Adaptada. Neste contexto, objetiva-se por meio deste estudo, realizar uma breve revisão integrativa sobre o surf adaptado e o parasurf para pessoas com deficiência e o seu processo de desenvolvimento em âmbito nacional e internacional, em conjunto a uma revisão de literatura. Para tanto, o estudo caracteriza-se como uma pesquisa narrativa, com abordagem qualitativa. A partir da análise dos dados, foi possível observar que há escassez literária a respeito da temática, entretanto, nos últimos anos houve maior incidência da divulgação da modalidade, que mesmo pouca no meio acadêmico,  vem em ascensão sobre ambas as práticas paradesportivas seja para lazer ou para os fins do alto rendimento

Osteoblastoma clássico, osteoblastoma atípico e osteossarcoma: um estudo comparativo baseado em parâmetros clínicos, histológicos e biológicos

OBJECTIVE: To investigate the biological behavior of classical and atypical osteoblastomas in comparison to osteosarcomas. METHODS: Based on histological parameters, 30 osteoblastomas were subclassified as classical osteoblastomas (23/30) or atypical osteoblastoma (high cellularity, prominent blue osteoid, and epithelioid osteoblasts-7/30). Comparative immunohistochemical and clinical analysis was performed in 17 cases of patients with high-grade osteosarcoma. Formalin-fixed, paraffin-embedded archival tissue was immunostained for p53 and proliferation cell nuclear antigen. Tumors with positive p53 stain underwent molecular analyses for fragments of exon 10. RESULTS: The mean proliferating cell nuclear antigen indexes for classical osteoblastoma, atypical osteoblastoma, and osteosarcoma were 33%, 61%, and 79%, respectively. The atypical subgroup showed similar results to those of the osteosarcoma group (P ; 40 (P = 0.015). CONCLUSION: These results validate atypical osteoblastoma as an entity, with p53 and proliferation cell nuclear antigen immunoexpression closer to that of osteosarcoma than of classical osteoblastoma. Proliferating cell nuclear antigen labeling index and p53 may be useful predictors of recurrence.OBJETIVOS: Investigar o comportamento biológico de osteoblastomas clássicos e atípicos comparados com osteossarcomas. MÉTODOS: Com base em parâmetros histológicos classificamos um grupo de 30 osteoblastomas nos subgrupos de osteoblastomas clássicos (23/30) e de osteoblastomas atípicos (que apresentam como característica grande celularidade, osteóide azul proeminente e osteoblastos epitelióide-7/30). Como efeito de comparação dos resultados imunohistoquímicos e análise clínica, avaliamos 17 pacientes com osteosarcoma de grau avançado. Os cortes histológicos com bloco de parafina fixado em formalina foram imunocorados para p53 e antígeno nuclear de célula em proliferação. Tumores com coloração positiva para p53 tiveram análise molecular para fragmentos do exon 10. RESULTADOS: O índice médio de antígeno nuclear de célula em proliferação para osteoblastoma clássico, osteoblastoma atípico e osteosarcoma foram de 33%, 61% e 79%, respectivamente. O subgrupo atípico demonstrou resultados similares aos dos osteosarcomas (p; 40 (p=0,015). CONCLUSÃO: Esses resultados validam os osteoblastomas atípicos como entidade real, com imunoexpressão das proteínas p53 e antígeno nuclear de célula em proliferação mais perto do osteosarcoma do que do osteoblastoma clássico. O índice de marcação pelo antígeno nuclear de célula em proliferação e o p53 podem ser úteis fatores de prognóstico da recorrência

Structure of Hierridin C, Synthesis of Hierridins B and C, and Evidence for Prevalent Alkylresorcinol Biosynthesis in Picocyanobacteria

Small, single-celled planktonic cyanobacteria are ubiquitous in the world's oceans yet tend not to be perceived as secondary metabolite-rich organisms. Here we report the isolation and structure elucidation of hierridin C, a minor metabolite obtained from the cultured picocyanobacterium Cyanobium sp. LEGE 06113. We describe a simple, straightforward synthetic route to the scarcely produced hierridins that relies on a key regioselective halogenation step. In addition, we show that these compounds originate from a type III PKS pathway and that similar biosynthetic gene clusters are found in a variety of bacterial genomes, most notably those of the globally distributed picocyanobacteria genera Prochlorococcus, Cyanobium and Synechococcus.info:eu-repo/semantics/publishedVersio

Analysis of the mRNA expression of the S100β protein in adipocytes of patients with diabetes mellitus, type 2

OBJETIVO: O presente trabalho objetiva compreender a possível relação do nível de expressão gênica do mRNA da proteína S100β em adipócitos com o diabetes melito do tipo 2, pela comparação de dados de portadores dessa doença com os de indivíduos normoglicêmicos. MATERIAIS E MÉTODOS: Foram selecionadas amostras de tecido adiposo de oito pacientes da Seção de Coronárias do Instituto Dante Pazzanese de Cardiologia (IDPC), sendo quatro do grupo diabetes e quatro do grupo de normoglicêmicos. Essas amostras foram submetidas à técnica de RT-PCR em tempo real. RESULTADOS: Por meio do Test-t de Student para os valores de diferença entre os ciclos threshold (ΔCt), observou-se que houve aumento de aproximadamente 15 vezes (p = 0,015) da expressão do mRNA da proteína S100β nos adipócitos dos indivíduos do grupo diabetes quando comparado aos do grupo controle. CONCLUSÃO: Nossos resultados evidenciam, de forma inédita, coexistência entre o aumento da expressão do gene S100β e a patologia do diabetes melito do tipo 2

Novel Potent Metallocenes against Liver Stage Malaria

Novel conjugates of the antimalarial drug primaquine (compound 1) with ferrocene, named primacenes, have been synthesized and screened for their activities against blood stage and liver stage malaria in vitro and host-vector transmission in vivo. Both transmission-blocking and blood-schizontocidal activities of the parent drug were conserved only in primacenes bearing a basic aliphatic amine group. Liver stage activity did not require this structural feature, and all metallocenes tested were comparable to or better than primaquine in this regard. Remarkably, the replacement of primaquine's aliphatic chain by hexylferrocene, as in compound 7, led to a similar to 45-fold-higher level activity against liver stage parasitemia than that of primaquine

Maternal mortality in adolescents and young adults: temporal trend and correlation with prenatal care coverage in the state of Bahia, Brazil, 2000-2020

ABSTRACT Objective: to analyze the temporal trend of maternal mortality and correlate it with prenatal care coverage among adolescents and young adults, state of Bahia, Brazil, 2000-2020. Methods: this was an ecological time-series study and correlation between maternal deaths and prenatal care visits in 10-19 and 20-24 age groups, using the Mortality Information System; the trend analysis was performed by means of Prais-Winsten regression, according to race/skin color, timing and causes of death; and Spearman coefficient was used for correlation. Results: in the study period, 418 deaths among adolescents and 574 among young adults were recorded; maternal mortality ratio was 59.7 and 63.2 deaths/100,000 live births, with a significant decreasing trend (-2.2% and -2.9% respectively); it could be seen an inverse correlation between a higher number of prenatal care visits and maternal mortality in the age groups. Conclusion: maternal mortality showed a decreasing trend in the study period, but with high proportions of death; there was a significant correlation between prenatal care coverage and maternal mortality among adolescents and young adults

Relationship between circulating VCAM-1, ICAM-1, E-selectin and MMP9 and the extent of coronary lesions

OBJECTIVES: Inflammatory molecules play a role in the development of atherosclerosis, which is the primary origin of cardiovascular disorders. However, to the best of our knowledge, no study has attempted to investigate the relationship between these circulating molecules and the prediction of cardiovascular risk. The present study aimed to investigate the relationships of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, E-selectin and matrix metalloproteinase 9 serum concentrations with the extent of coronary lesions. METHODS: Seventy-four individuals who were undergoing coronary angiography for the first time for diagnostic purposes were enrolled in this study. The extent of the coronary lesion was assessed using the Friesinger Index, and subjects were classified into four groups: no lesions, minor lesions, intermediate lesions and major lesions. Serum biochemical parameters and serum concentrations of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, E-selectin and matrix metalloproteinase 9 were analyzed. RESULTS: The vascular cell adhesion molecule-1 concentration was higher than 876 ng/mL in individuals with intermediate and major lesions (

Photodegradation of Phenol over a Hybrid Organo-Inorganic Material: Iron(II) Hydroxyphosphonoacetate

Water treatment is a hot topic, and it will become much more important in the decades ahead. Advanced oxidation processes are being increasingly used for organic contaminant removal, for example using photo-Fenton reactions. Here we report the use of an organo-inorganic hybrid, Fe[HO3PCH(OH)COO]·2H2O, as Fenton photocatalyst for phenol oxidation with H2O2 under UVA radiation. Preactivation, catalyst content, and particle size parameters have been studied/optimized for increasing phenol mineralization. Upon reaction, iron species are leached from the catalyst making a homogeneous catalysis contribution to the overall phenol photo-oxidation. Under optimized conditions, the mineralization degree was slightly larger than 90% after 80 min of irradiation. Analysis by X-ray photoelectron spectroscopy revealed important chemical modifications occurring on the surface of the catalyst after activation and phenol photodegradation. The sustained slow delivery of iron species upon phenol photoreaction is advantageous as the mixed heterogeneous−homogeneous catalytic processes result in very high phenol mineralization.Proyecto nacional MAT2010-1517