Abstract Background: Chronic Chagas cardiomyopathy (CCC) is caused by an inflammatory process induced by Trypanosoma cruzi, which leads to myocarditis with reactive and reparative fibrosis. CCC progresses with myocardial perfusion abnormalities and histopathological events that affect cardiorespiratory fitness (CRF). Objectives: We evaluated the effects of aerobic physical training (APT) on myocardial perfusion and on morphological and functional impairments related with inflammation and fibrosis in Syrian hamsters with CCC. As a secondary objective, we analyzed the cross-sectional areas of the skeletal muscle. Methods: Hamsters with CCC and their respective controls were divided into four groups: CCC sedentary, CCC-APT, sedentary control and APT control. Seven months after infection, the animals underwent echocardiography, myocardial perfusion scintigraphy and cardiopulmonary exercise testing. Moderate-intensity APT was performed for fifty minutes, five times a week, for eight weeks. Subsequently, the animals were reassessed. Histopathological analysis was conducted after the above-mentioned procedures. The level of significance was set at 5% in all analyses (p<0.05). Results: CCC sedentary animals presented worse myocardial perfusion defects (MPD) over time, reduced left ventricle ejection fraction (LVEF) and showed more inflammation and fibrosis when compared to other groups (mixed ANOVA analysis). Conversely, APT was able to mitigate the progression of MPD, ameliorate inflammation and fibrosis and improve CRF efficiency in CCC-APT animals. Conclusions: Our study demonstrated that APT ameliorated cardiac dysfunction, MPD, and reduced inflammation and fibrosis in CCC hamster models. Additionally, CCC-SED animals presented skeletal muscle atrophy while CCC-APT animals showed preserved skeletal muscle CSA. Understanding APT's effects on CCC's pathophysiological dimensions is crucial for future research and therapeutic interventions. Background (CCC cruzi CRF. . (CRF) Objectives (APT objective crosssectional cross sectional Methods CCCAPT, CCCAPT APT, infection echocardiography testing Moderateintensity Moderate intensity minutes week weeks Subsequently reassessed abovementioned above mentioned procedures 5 p<0.05. p005 p p<0.05 0 05 (p<0.05) Results MPD (MPD time LVEF (LVEF mixed analysis. analysis) Conversely Conclusions dysfunction models Additionally CCCSED SED CSA APTs s CCCs interventions (CRF p00 p<0.0 (p<0.05 p0 p<0. (p<0.0 p<0 (p<0. p< (p<0 (p< (p

Resumo Fundamento: A Cardiomiopatia Chagásica Crônica (CCC) é causada por um processo inflamatório induzido pelo Trypanosoma cruzi, que leva à miocardite com fibrose reativa e reparativa. A CCC progride com alterações de perfusão miocárdica e eventos histopatológicos que afetam a Aptidão Cardiorrespiratória (ACR). Objetivos: Avaliamos os efeitos do Treinamento Físico Aeróbico (TFA) na perfusão miocárdica e nos comprometimentos morfológicos e funcionais relacionados à inflamação e fibrose em hamsters sírios com CCC. Como objetivo secundário, analisamos as áreas de secção transversa do músculo esquelético. Métodos: Hamsters com CCC e seus respectivos controles foram divididos em quatro grupos: CCC sedentário, CCC-TFA, controle sedentário e controle TFA. Sete meses após a infecção, os animais foram submetidos à ecocardiografia, à cintilografia de perfusão miocárdica e ao teste de esforço cardiopulmonar. TFA de intensidade moderada foi realizado durante cinquenta minutos, cinco vezes por semana, por oito semanas. Posteriormente, os animais foram reavaliados. A análise histopatológica foi realizada após os procedimentos acima mencionados. O nível de significância foi estabelecido em 5% em todas as análises (p<0,05). Resultados: Animais com CCC sedentários apresentaram piores Defeitos de Perfusão Miocárdica (DPM) ao longo do tempo, Fração de Ejeção do Ventrículo Esquerdo (FEVE) reduzida, e apresentaram mais inflamação e fibrose quando comparados aos demais grupos (análise ANOVA mista). Por outro lado, o TFA foi capaz de mitigar a progressão do DPM, atenuar a inflamação e a fibrose e melhorar a eficiência da ACR em animais CCC-TFA. Conclusão: Nosso estudo demonstrou que o TFA melhorou a disfunção cardíaca, DPM e reduziu a inflamação e a fibrose em modelos de hamster com CCC. Além disso, os animais CCC-SED apresentaram atrofia do músculo esquelético, enquanto os animais CCC-TFA apresentaram a AST do músculo esquelético preservada. Compreender os efeitos da TFA nas dimensões fisiopatológicas da CCC é crucial para futuras pesquisas e intervenções terapêuticas. Fundamento (CCC cruzi reparativa ACR. . (ACR) Objetivos (TFA secundário Métodos CCCTFA, CCCTFA TFA, infecção ecocardiografia cardiopulmonar minutos semana semanas Posteriormente reavaliados mencionados 5 p<0,05. p005 p p<0,05 0 05 (p<0,05) Resultados (DPM tempo FEVE (FEVE reduzida mista. mista mista) lado CCCTFA. Conclusão cardíaca disso CCCSED SED preservada terapêuticas (ACR p00 p<0,0 (p<0,05 p0 p<0, (p<0,0 p<0 (p<0, p< (p<0 (p< (p

Abstract The present study sought to evaluate the antimicrobial and anti-adherent potential of Eucalyptus radiata essential oil against food-borne strains of Escherichia coli. The study was performed using the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). In addition, the disk diffusion technique was used to evaluate the association of Eucalyptus radiata essential oil with synthetic antimicrobials. The Minimum Inhibitory Adherence Concentration (MIC) was also performed. The results revealed that E. radiata showed antimicrobial activity against the E. coli strains tested, with MIC values ranging from 500 μg/mL to 1000 μg/mL and MBC values ranging from 500 μg/mL to 1,024 μg/mL. As for the associations, it was observed that E. radiata oil exhibited a synergistic effect for some antibiotics, especially Ceftriaxone, with greater interference from the essential oil. Furthermore, it was effective in inhibiting the adherence of bacterial strains of E. coli, showing a more significant antibiofilm effect than the antibacterial agent 0.12% chlorhexidine digluconate. In summary, the essential oil of E. radiata showed antimicrobial potential against strains of E. coli of food origin, and can therefore, through in-depth studies, be used alone or in association with synthetic antimicrobials to combat infections caused by this pathogen. antiadherent anti adherent foodborne borne (MIC MBC. . (MBC) addition E tested 50 μgmL μg mL 100 1024 1 024 1,02 associations antibiotics Ceftriaxone Furthermore 012 0 12 0.12 digluconate summary origin therefore indepth depth studies pathogen (MBC 5 10 102 02 1,0 01 0.1 1, 0.

Resumo O presente estudo buscou avaliar o potencial antimicrobiano e antiaderente do óleo essencial de Eucalipto radiata frente às cepas de veiculação alimentar de Escherichia coli. O estudo foi realizado usando a Concentração Inibitória Mínima (CIM) e Concentração Bactericida Mínima (CBM). Além disso, a técnica de difusão em disco foi usada para avaliar a associação do óleo essencial de Eucalipto radiata com antimicrobianos sintéticos. A Concentração Inibitória Mínima de Aderência (CIMA) também foi realizada. Os resultados revelaram que E. radiata apresentou atividade antimicrobiana contra as cepas de E. coli testadas, com valores de CIM variando entre 500 μg/mL a 1000 μg/mL e valores de CBM variando entre 500 μg/mL a 1,024 μg/mL. Quanto às associações, observou-se que o óleo de E. radiata exibiu efeito sinérgico para alguns antibióticos, sobretudo a Ceftriaxona, apresentando maior interferência do óleo essencial. Além disso, foi eficaz na inibição a aderência das cepas bacterianas de E. coli, mostrando um efeito antibiofilme mais significativo que o agente antibacteriano digluconato de clorexidina a 0.12%. Em resumo, o óleo essencial de E. radiata apresentou potencial antimicrobiano contra cepas de E. coli de origem alimentar, podendo assim, mediante estudos aprofundados, ser utilizado isoladamente ou em associação com antimicrobianos sintéticos para combater infecções causadas por esse patógeno. (CIM CBM. . (CBM) disso CIMA (CIMA realizada E testadas 50 μgmL μg mL 100 1024 1 024 1,02 associações observouse observou se antibióticos Ceftriaxona 012 0 12 0.12% resumo assim aprofundados patógeno (CBM 5 10 102 02 1,0 01 0.12 1, 0.1 0.

Abstract Birds kept in captivity are subject to various diseases that affect their well-being, with parasites being among the most common. The aim of this study was to report the occurrence of endoparasites in the feces of birds kept in captivity at Fortaleza Zoo, using the Willis Mollay and Hoffman techniques. Of the samples analyzed, 50.98% were positive for endoparasites, including the suborder Coccidia, the genera Capillaria spp., Strongyloides spp., Ascaridia spp., Libyostrongylus spp., cysts of a specific parasite of Ostriches, Balantidium spp., the Strongyloidea superfamily and cestodes. In conclusion, the wild birds in the zoo investigated had a diversity of endoparasites and a considerable infection rate. wellbeing, wellbeing well being, well-being common Zoo techniques analyzed 5098 50 98 50.98 Coccidia spp spp. Ostriches cestodes conclusion rate 509 5 9 50.9 50.

Resumo As aves mantidas em cativeiro estão sujeitas a diversas enfermidades que afetam seu bem-estar, estando as parasitoses entre as mais frequentes. Este trabalho teve como objetivo relatar a ocorrência de endoparasitas em fezes de aves alojadas em cativeiro no zoológico de Fortaleza, utilizando as técnicas de Willis Mollay e de Hoffman. Das amostras analisadas, 50,98% foram positivas para endoparasitas, incluindo os da subordem Coccidia., os gêneros Capillaria spp., Strongyloides spp., Ascaridia spp., Libyostrongylus spp. (parasita específico de Avestruzes), cisto de Balantidium spp., superfamília Strongyloidea e cestódeos. Conclui-se que as aves silvestres do zoológico investigado apresentaram, além de uma diversidade de endoparasitas, uma considerável taxa de infecção. bemestar, bemestar bem estar, estar bem-estar frequentes Fortaleza Hoffman analisadas 5098 50 98 50,98 Coccidia Coccidia. spp parasita Avestruzes, Avestruzes , Avestruzes) cestódeos Concluise Conclui se apresentaram infecção 509 5 9 50,9 50,

Resumo Fundamento O padrão-ouro atual dos stents farmacológicos (SF) coronários consiste em ligas metálicas com hastes mais finas e polímeros bioabsorvíveis. Objetivos Nosso objetivo foi comparar um stent eluidor de sirolimus de hastes ultrafinas (Inspiron®) com outras plataformas de SF de terceira geração em pacientes com infarto do miocárdio com supradesnivelamento do segmento ST (IAMCSST) submetidos à intervenção coronária percutânea (ICP) primária. Métodos Analisamos dados de um registro multicêntrico de IAMCSST de centros de referência da Região Sul do Brasil. Todos os pacientes foram submetidos à ICP primária, seja com Inspiron® ou outro SF de segunda ou terceira geração. Foi calculado pareamento por escore de propensão (PEP) para gerar grupos semelhantes (Inspiron® versus outros stents) em relação às características clínicas e do procedimento. Todos os testes de hipótese tiveram um nível de significância bilateral de 0,05. Resultados De janeiro de 2017 a janeiro de 2021, 1.711 pacientes foram submetidos à ICP primária, e 1.417 pacientes preencheram nossos critérios de inclusão (709 pacientes no grupo Inspiron® e 708 pacientes no grupo dos outros SF de segunda ou terceira geração). Após PEP, a amostra do estudo foi composta por 706 pacientes (353 pacientes no grupo Inspiron® e 353 pacientes no grupo dos demais SF de segunda ou terceira geração). As taxas de revascularização do vaso alvo (odds ratio [OR] 0,52; intervalo de confiança [IC] 0,21 a 1,34; p = 0,173), trombose de stent (OR 1,00; IC 0,29 a 3,48;p = 1,000), mortalidade (hazard ratio 0,724; IC 0,41 a 1,27; p = 0,257) e os desfechos cardiovasculares maiores (OR 1,170; IC 0,77 a 1,77; p = 0,526) foram semelhantes entre os grupos após um acompanhamento mediano de 17 meses. Conclusão Nossos achados mostram que o stent Inspiron® foi eficaz e seguro quando comparado a outros SF de segunda ou terceira geração em uma coorte contemporânea do mundo real de pacientes com IAMCSST submetidos à ICP primária. padrãoouro padrão ouro (SF bioabsorvíveis Inspiron (IAMCSST (ICP primária Brasil PEP (PEP (Inspiron procedimento 005 0 05 0,05 201 2021 1711 1 711 1.71 1417 417 1.41 709 (70 70 . geração) (35 35 odds OR [OR 0,52 052 52 [IC 021 21 0,2 1,34 134 34 0,173, 0173 0,173 , 173 0,173) 1,00 100 00 029 29 3,48p 348p 3,48 3 48 1,000, 1000 1,000 000 1,000) hazard 0,724 0724 724 041 41 0,4 1,27 127 27 0,257 0257 257 1,170 1170 170 077 77 0,7 1,77 177 0,526 0526 526 meses 0,0 20 202 171 71 1.7 141 1.4 (7 7 (3 0,5 5 02 2 0, 1,3 13 017 0,17 1,0 10 48p 348 3,4 4 0,72 072 72 04 1,2 12 0,25 025 25 1,17 117 07 1,7 1. 14 ( 1, 01 0,1 3, 1,1 11

Abstract Background The current gold standard of coronary drug-eluting stents (DES) consists of metal alloys with thinner struts and bioresorbable polymers. Objectives Our aim was to compare an ultrathin strut, sirolimus-eluting stent (Inspiron®) with other third-generation DES platforms in patients with ST-elevation myocardial infarction (STEMI) submitted to primary percutaneous coronary intervention (PCI). Methods We analyzed data from a STEMI multicenter registry from reference centers in the South Region of Brazil. All patients were submitted to primary PCI, either with Inspiron® or other second- or third-generation DES. Propensity score matching (PSM) was computed to generate similar groups (Inspiron® versus other stents) in relation to clinical and procedural characteristics. All hypothesis tests had a two-sided significance level of 0.05. Results From January 2017 to January 2021, 1711 patients underwent primary PCI, and 1417 patients met our entry criteria (709 patients in the Inspiron® group and 708 patients in the other second- or third-generation DES group). After PSM, the study sample was comprised of 706 patients (353 patients in the Inspiron® group and 353 patients in the other the other second- or third-generation DES group). The rates of target vessel revascularization (OR 0.52, CI 0.21 – 1.34, p = 0.173), stent thrombosis (OR 1.00, CI 0.29 – 3.48, p = 1.000), mortality (HR 0.724, CI 0.41 – 1.27, p = 0.257), and major cardiovascular outcomes (OR 1.170, CI 0.77 – 1.77, p = 0.526) were similar between groups after a median follow-up of 17 months. Conclusion Our findings show that Inspiron® was effective and safe when compared to other second- or third-generation DES in a contemporary cohort of real-world STEMI patients submitted to primary PCI. drugeluting drug eluting (DES polymers strut sirolimuseluting sirolimus Inspiron thirdgeneration third generation STelevation ST elevation (STEMI PCI . (PCI) Brazil second PSM (PSM (Inspiron characteristics twosided two sided 005 0 05 0.05 201 2021 171 141 709 (70 70 group. group) (35 35 OR 052 52 0.52 021 21 0.2 134 1 34 1.34 0.173, 0173 0.173 , 173 0.173) 100 00 1.00 029 29 348 3 48 3.48 1.000, 1000 1.000 000 1.000) HR 0724 724 0.724 041 41 0.4 127 27 1.27 0.257, 0257 0.257 257 0.257) 1170 170 1.170 077 77 0.7 177 1.77 0.526 0526 526 followup follow up months realworld real world (PCI 0.0 20 202 14 (7 7 (3 5 0.5 02 2 0. 13 1.3 017 0.17 10 1.0 4 3.4 072 72 0.72 04 12 1.2 025 0.25 25 117 1.17 07 1.7 ( 1. 01 0.1 3. 11 1.1

Abstract Introduction The incidence of antimicrobial resistance is increasing in many parts of the world. The focus of this report is to examine changes in antimicrobial resistance epidemiology among clinical isolates of Enterobacterales and Pseudomonas aeruginosa collected in six Latin American countries as part of the Antimicrobial Testing Leadership and Surveillance (ATLAS) program from 2015 to 2020, with a focus on the in vitro activity of ceftazidime-avibactam against Multidrug-Resistant (MDR) isolates. Methods Non-duplicate, clinical isolates of Enterobacterales (n= 15,215) and P. aeruginosa (n= 4,614) collected by 40 laboratories in Argentina, Brazil, Chile, Colombia, Mexico, and Venezuela, from 2015 to 2020, underwent centralized Clinical Lab Standards Institute (CLSI) broth microdilution susceptibility testing. Minimum Inhibitory Concentration (MIC) values were interpreted using 2022 CLSI breakpoints. An MDR phenotype was defined by resistance to ≥ 3 of seven sentinel agents. Results In total, 23.3% of Enterobacterales and 25.1% of P. aeruginosa isolates were MDR. Annual percent MDR values for Enterobacterales were stable from 2015 to 2018 (21.3% to 23.7% year) but markedly increased in 2019 (31.5%) and 2020 (32.4%). Annual percent MDR values for P. aeruginosa were stable from 2015 to 2020 (23.0% to 27.6% year). Isolates were divided into two 3-year time-periods, 2015‒2017 and 2018‒2020, for additional analyses. For Enterobacterales, 99.3% of all isolates and 97.1% of MDR isolates from 2015‒2017 were ceftazidime-avibactam-susceptible compared to 97.2% and 89.3% of isolates, respectively, from 2018‒2020. For P. aeruginosa, 86.6% of all isolates and 53.9% of MDR isolates from 2015‒2017 were ceftazidime-avibactam-susceptible compared to 85.3% and 45.3% of isolates, respectively, from 2018‒2020. Among individual countries, Enterobacterales and P. aeruginosa collected in Venezuela showed the greatest reductions in ceftazidime-avibactam susceptibility over time. Conclusion MDR Enterobacterales increased in Latin America from 22% in 2015 to 32% in 2020 while MDR P. aeruginosa remained constant at 25%. Ceftazidime-avibactam remains highly active against all clinical isolates of both Enterobacterales (97.2% susceptible, 2018‒2020) and P. aeruginosa (85.3%), and inhibited more MDR isolates (Enterobacterales, 89.3% susceptible, 2018‒2020; P. aeruginosa, 45.3%) than carbapenems, fluoroquinolones, and aminoglycosides.

ABSTRACT Ceftazidime/avibactam (CAZ/AVI) has excellent in vitro activity against enterobacterales and Pseudomonas aeruginosa. The study aimed to analyze the in vitro antimicrobial activity of CAZ/AVI and other antibiotics against isolates of enterobacterales and P. aeruginosa from patients with complicated urinary tract infection (cUTI) and complicated intra-abdominal infection (cIAI) in Colombian hospitals between 2014 and 2018, using the Antimicrobial Testing Leadership and Surveillance (ATLAS) database. Enterobacterales and P. aeruginosa samples were obtained from patients with cUTI and cIAI. Susceptibility was determined using The Clinical and Laboratory Standards Institute (CLSI) breakpoints. Meropenem-non-susceptible isolates were screened for extended-spectrum b-lactamase (ESBL) production. Isolates that were positive for ESBL activity were examined by Multiplex Polymerase Chain Reaction (Multiplex PCR) to detect genotypic resistance. A total of 565 Enterobacterales and 95 P. aeruginosa from patients with cUTI and 345 Enterobacterales and 65 P. aeruginosa from patients with cIAI were isolated. In vitro activity showed susceptibility to CAZ/AVI greater than 99% for Enterobacterales and in lower percentages for P. aeruginosa in cUTI (78.46%) and cIAI (83.33%). CAZ/AVI showed good in vitro activity against multidrug-resistant (MDR) Enterobacterales and P. aeruginosa in patients with cUTI and cIAI.

Abstract Maximum spatial eigenfiltering improves the accuracy of maximum likelihood direction-of-arrival estimators for closely-spaced signal sources but may interchangeably attenuate widely-spaced signal sources, producing a severe performance degradation. Although this behavior has been observed experimentally, it still lacks a mathematical explanation. In our previous work, we overcame these limitations using a differential spectrum-based spatial filter but this still caused a small degradation in the DOA estimate. In this paper, we develop a mathematical analysis of how the signal source separation and the Karhunen-Loève expansion affect the passbands of the maximum spatial eigenfilter. The farther the sources, the less significant is the maximum eigenvalue of the spatial correlation matrix and its corresponding eigenvector. Then, the magnitude response of the maximum spatial eigenfilter no longer approximates the spatial power spectrum and is not guaranteed to place multiple passbands around the signal sources. Consequently, we propose a spatial filter built from the eigenvectors of the entire signal subspace. This filter showed an overall runtime smaller than that of our previous work. It also provides a significant reduction in the threshold signal-to-noise ratio for closely-spaced signal sources and does not hamper the estimation for widely-spaced signal sources.

Abstract Diet supplementation with essential oil from sweet basil Ocimum basilicum (EOOB) can increase fish growth. So, this study aimed to evaluate the effect of EOOB in the diet on growth performance and plasmatic variables of pirarucu juveniles (Arapaima gigas) submitted to stressful condition (stocking density of 7.56 kg m-3per tank and limited space). Four diets (in triplicates) were evaluated with increasing levels of EOOB (0.0 control; 0.5; 1.0; and 2.0 mL kg diet-1) over 48 days. Linalool was the major constituent of EOOB (54.19%). The addition of 2.0 mL EOOB kg diet-1 improved final weight, weight gain, specific growth rate, condition factor and feed conversion ratio; it also decreased plasma urea levels and increased plasma albumin and total proteins levels. Plasma glucose, cortisol, and acid uric levels were not influenced by the addition of EOOB to the fish diet. In conclusion, the addition of 2.0 mL EOOBkg diet-1 is recommended for pirarucu juveniles, due to improved growth performance, and this supplementation did not compromise the homeostasis of fish rearing in a high stocking density.

Abstract The essential oils obtained by hydrodistillation from fresh leaves of Vitex agnus-castus and Ocimum campechianum, and from fresh inflorescences of Ocimum carnosum were analysed by GC-FID and GC-MS. The major components of V. agnus-castus essential oil were identified as 1,8-cineole (47.9%), terpinyl α-acetate (11.6%), sabinene (11.2%) and caryophyllene oxide (9.7%), while in the O. campechianum essential oil were eugenol (72.1%), β-elemene (6.8%), (E)-caryophyllene (6.4%) and bicyclogermacrene (5.2%). Linalool (79.0%), α-epi-cadinol (5.4%), terpinen-4-ol (3.2%) and 1,8-cineole (2.8%) were the major constituents in the O. carnosum essential oil. The essential oils were subsequently evaluated for their larvicidal and cytotoxic activities. Larval bioassay against Aedes aegypti of V. agnus-castus, O. campechianum and O. carnosum essential oils showed LC50 values of 97.55 ± 0.35, 81.45 ± 0.35 and 109.49 ± 0.35 μg/mL, respectively. The in vitro cytotoxic activities of the essential oils has been evaluated on breast adenocarcinoma (MCF-7), lung carcinoma (NCI-H292), pro-myelocytic leukemia (HL-60), and cervical adenocarcinoma (HEP-2) human cell lines, and pro-myelocytic leukemia cells lines (HL-60) were found to be the most sensitive to all the essential oils tested than the others. This is the first report on larvicidal and cytotoxic activities of these essential oils.

ABSTRACT Banded iron formations (BIF) have a particular vegetation type and provide a good model system for testing theories related to leaf phenology, due to unique stressful environmental conditions. As a consequence of the stressful conditions of BIF environment, we hypothesize that most species would retain at least some significant canopy cover, even at the end of the dry season, independently of growth form - trees, shrubs, and sub-shrubs. Considering the strong seasonality, we also hypothesize that photoperiod and rainfall act as triggers for leaf fall and leaf flushing in these environments. The majority of the fifteen studied species had a semi-deciduous behavior and shed their leaves mainly during the dry season, with a recovery at the end of this season. In general, leaf flushing increased around the spring equinox (end of the dry season and start of the rainy season). A trade-off between leaf loss and leaf maintenance is expected in a community in which most plants are naturally selected to be semi-deciduous. Our results suggest photoperiod as a dominant factor in predicting leaf phenology.

Este estudo avalia a intercalação de esmectita dioctahédrica do Estado Acre com o sal quaternário de amônio brometo de hexadeciltrimetilamônio (HDTMA) em concentrações compreendidas entre 1 a 5 vezes ao valor de CTC da argila original e sua aplicabilidade na adsorção de fenol e benzeno em fase líquida. Os materiais foram caracterizados por microanálises de difração de raios X, microscopia eletrônica de varredura/espectroscopia com dispersão de energia e espectroscopia na região do infravermelho. Os processos de adsorção foram realizados em sistemas simples e as medidas das concentrações do fenol e benzeno foram efetuadas por espectrofotometria na região ultravioleta. Os resultados indicaram que a intercalação da esmectita com HDTMA propiciou cerca de 78,8% de expansão (variação de d001: 1,47 nm para 1,91 nm) e decréscimo acentuado dos elementos das posições interlamelares, como Na, Ca, Mg e K, acompanhado pela delaminação/esfoliação da argila original. Nos processos de adsorção do fenol e benzeno em HDTMA-arg 5 foram obtidos os seguintes resultados: q max= 4,44 e 35,8 mg.g-1; K L= 0,076 e 0,115 L.g-1; ΔGº = -16,85 e -18,38 kJ.mol-1, respectivamente. Estes dados indicaram que os processos de adsorção do benzeno e fenol em fase líquida na organoargila HDTMA-arg 5 foram favoráveis, espontâneos e com interações físicas.

This study evaluates the intercalation of the smectite dioctahedric state of Acre, Brazil, with the quaternary ammonium salt bromide, hexadecyltrimethylammonium (HDTMA) at concentrations ranging from 1 to 5 times the value of the original clay CEC and its application in the adsorption of phenol and benzene in the liquid phase. The materials were characterized by microanalysis X-ray diffraction, scanning electron microscopy /energy dispersive spectroscopy and infrared spectroscopy. The adsorption processes were carried out in simple systems and measurements of the concentrations of phenol and benzene were performed by spectrophotometry in the ultraviolet region. The results indicated that the intercalation of smectite with HDTMA provided approximately 78.8 expansion (range d001: 1.47 nm to 1.91 nm) and sharp decrease of the interlayer positions of elements such as Na, Ca, Mg and K, together by delamination/exfoliation of the clay original. In adsorption processes of phenol and benzene at HDTMA-arg 5 the following results were obtained: q max = 4.44 and 35.8 mg.g-1; K L= 0.076 and 0.115 L.g-1; ΔGº = -16.85 and -18.38 kJ.mol-1, respectively. These data indicated that the adsorption of benzene and phenol in liquid phase in the organophilic HDTMA-arg 5 were favorable, spontaneous and physical interactions.

Este estudo avalia a eficiência, viabilidade e espontaneidade de processos de adsorção do íon nitrato em caulinita sem tratamento e modificada com uréia, empregando como material de partida o rejeito de processamento de caulim do rio Jari. Os materiais foram caracterizados por difração de raios X, fluorescência de raios X e espectroscopia IV (DRX, FRX e FTIR). As medidas de pH de equilíbrio foram efetuadas por potenciometria e as concentrações de equilíbrio (Ce) de nitrato medidas por cromatografia iônica. Quantidades adsorvidas no equilíbrio (qe), constantes de distribuição (Kd=qe/Ce), fator de separação (R L) e variação de energia livre de Gibbs (ΔGº), foram calculados com base nos dados experimentais de adsorção. Os resultados de DRX e FTIR confirmaram a formação do complexo caulinita-uréia a partir do tratamento efetuado no rejeito de caulim. Os seguintes dados foram obtidos nos processos de adsorção de nitrato, no rejeito de caulim natural e tratado com uréia: q max= 18,17 e 14,1 mmol kg-1; Kd=0,7-2,2 e 0,45-1,5 L Kg-1; R L= 0,35-0,85 e 0,25-0,80; ΔGº= -9,3 a -5,8 e -9,1 a -5,4 kJ mol-1, respectivamente. Os valores de Kd, ΔGº e R L são típicos de processos de adsorção física (fisissorção), viáveis e espontâneos e os de q max indicam que a retenção de nitrato em rejeito de caulim natural é mais eficiente do que em rejeito modificado com uréia.

This study evaluates the the efficiency, feasibility and spontaneity of the adsorption of nitrate ion in natural and modified kaolinite with urea, using as starting material kaolin waste processing from Jari River. The materials were characterized by X-ray diffraction, X-ray fluorescence, Fourier transform IR spectroscopy (XRD, XRF and FTIR, respectively). The equilibrium pH measurements were performed by potentiometry and the equilibrium concentrations (Ce) nitrate was measured by ion chromatography. Amounts adsorbed at equilibrium (qe), distribution constant (Kd = qe / Ce), separation factor (R L) and variation of Gibbs free energy (ΔG °) were calculated based on experimental data adsorption. The results of XRD and FTIR confirmed the formation of the kaolinite-urea from treatment carried out on kaolin waste. The following data were obtained from the adsorption of nitrate on natural kaolin waste and treated with urea: qmax = 18.17 and 14.1 mmol kg-1; Kd = 0.7 to 2.2 and 0.45 - 1.5 L kg-1; R L = 0.35 to 0.85 and 0.25 to 0.80; ΔG ° = -9.3 to -5.8 and -9.1 to -5.4 kJ mol-1, respectively. The values of Kd , ΔGº and R L are typical of physisorption processes, feasible and spontaneous and those qmax indicate that the retention of nitrate on natural kaolin waste is more efficient than on kaolin waste modified with urea.

Sedimentos argilosos provenientes do município Assis Brasil, Acre, foram lixiviados com soluções de ácido sulfúrico, ácido húmico e uréia, visando avaliar a capacidade de retenção de molibdato nesses materiais e investigar a viabilidade do processo de adsorção na interface sólido-solução. Os materiais foram caracterizados a partir de dados de difração de raios X, espectros FTIR, cargas superficiais e composição química. Os modelos de isotermas de Langmuir, Freundlich e Sips foram usados no ajuste dos dados experimentais de adsorção. Os minerais identificados nos sedimentos argilosos foram esmectita, caulinita, ilita, quartzo, albita, microclineo e calcita. A modificação química promoveu a amorfização da amostra modificada com ácido sulfúrico e delaminação ao longo do plano 001 da amostra modificada com uréia. Os ajustes matemáticos definidos pelos parâmetros (K L,Kf ) das isotermas de adsorção, avaliação de Ce vs. q e, pH vs. q e ,Qmáx (sips) e Kd indicaram que a amostra S10H15 é a mais eficiente na adsorção de MoO4(2-), com q máx = 6,83 mg.L-1.

Clay sediments from the municipalities Assis Brazil (Acre), were leached with solutions of sulfuric acid, humic acid and urea, to evaluate the retention capacity of molybdate in these materials and to investigate the feasibility of the adsorption processes at solid-solution interfaces. The materials were characterized from data of XRD, FTIR spectra, surface charge and chemical composition. The Langmuir isotherm models, Freundlich and Sips were used to fit the experimental data of adsorption. The minerals identified in the clay sediments were smectite, kaolinite, illite, quartz, albite, calcite and microclineo. The chemical modification leads amorphization of the modified sample with sulfuric acid and delamination along the plane 001 of the modified sample with urea. The settings defined by mathematical parameters (K L, Kf) of the adsorption isotherms, evaluation Ce vs. q e, pH vs. q e, Qmax (sips) and Kd, indicated that the S10H15 sample is more efficient in the adsorption MoO4(2-) ,with com q máx = 6.83 mg.L-1.

The chromatography fractionation of the hexane, chloroform and ethyl acetate extracts from the leaves and stems of Rourea doniana Baker, Connaraceae, resulted in the isolation of five triterpenes (lupeol, lupenone, α-amyrenone, β-amyrenone, and taraxerol), a flavonol (7,4'-dimethylkaempferol), a coumarin (scopoletin) and four phytosteroids (β-sitosterol, stigmasterol, β-sitosteryl-3-O-β- D-glucopyranoside and stigmasteryl-3-O-β-D-glucopyranoside). All compounds are being for the first time in this species and all triterpenes and the flavonol are being described for the first time in the family Connaraceae. These compounds were identified on basis of their IR and NMR (¹H, 13C, DEPT, HSQC, HMBC, and NOESY) spectral data and by comparison with literature data.