BENZILAÇÃO DO GLICEROL COM AQUECIMENTO POR MICROONDAS

A infinidade de aplicações da glicerina incentivou inúmeras pesquisas voltadas ao reaproveitamento do principal coproduto do biodiesel. Destaca-se a produção de aditivos oxigenados para combustíveis, como os éteres, os acetais e os ésteres de glicerina, processos estes que demandam um tempo de reação muito prolongado. Considerando que a aplicação da irradiação de microondas pode influenciar na cinética das reações químicas, o presente trabalho investigou a reação de benzilação do glicerol via catálise homogênea ácida, sob a irradiação de microondas. Foi constatado que o fator variação da potência das micro-ondas apresentou a maior conversão do glicerol dentre todas as variáveis estudadas. Em contrapartida, esta variável também influenciou uma reação indesejável, a autoeterificação do álcool benzílico.Palavras-chave: Benzilação. Glicerol. Álcool benzílico. Microondas.BENZYLATION OF GLYCEROL WITH HEATING BY MICROWAVEAbstract: The multitude of applications of glycerin has encouraged countless researches directed to the reutilization of the main byproduct of biodiesel. Highlighting the production of additives for oxygenated fuels, such as the ethers, the acetal and the esters of glycerin, those processes require a very long reaction time. Whereas the application of irradiation of microwave can influence on the kinetics of chemical reactions, the present work investigated the benzylation reaction of glycerol via catalysis homogeneous acid, in the irradiation of microwave. It was found that the factor power variation of microwave presented the greatest conversion of glycerol among all the variables studied. In contrast, that variable also influenced an undesirable reaction, the self-etherification of benzyl alcohol.Keywords: Benzylation. Glycerol. Benzyl alcohol. Microwave.BENZILACIÓN GLICERINA CON EL CALOR EN MICROONDASResumen: La grande cantidad de aplicaciones de la glicerina ha alentado numerosos estudios dirigidos a la reutilización del principal subproducto de biodiesel. Destacando la producción de aditivos oxigenados de combustibles para motores, tales como éteres, acetales y ésteres de glicerina, estos procedimientos requieren un tiempo de reacción muy largo. Considerando que la aplicación de irradiación de microondas puede influir en la cinética de las reacciones químicas, este estudio investigó la reacción de bencilación de glicerol a través de catálisis homogénea ácida bajo irradiación con microondas. Se encontró que la variación del factor potencia de microondas mostró la mayor conversión de glicerol entre todas las variables evaluadas. En contraste, esta variable también influenció una reacción indeseable, la auto-eterificación de alcohol bencílico.Palabras clave: Bencilación. Glicerol. Alcohol bencílico. Microondas

First report of infectious spleen and kidney necrosis virus (ISKNV) in two native cichlids cultured in Brazil

Peacock bass (syn.: tucunaré, Cichla ocellaris) and the pearl cichlids (syn.: acará, Geophagus brasiliensis) are South American cichlids that are highly valued in both the ornamental and sport fish industries. Since 2017, a number of outbreaks of infectious spleen and kidney necrosis virus (ISKNV) have been reported on Brazilian food and ornamental fish farms. In this study, we detected ISKNV in farmed peacock bass and pearl cichlid by PCR and sequence analysis of the partial major capsid protein (MCP) gene. Moribund peacock bass (n=10) and pearl cichlids (2) from a farm experiencing elevated mortality among juveniles and adults of these species, were submitted for bacteriological and molecular diagnostics. Spleen, liver, brain, and kidney tissues were cultured on 5% sheep blood agar and cystine heart agar with 1% glucose and bovine haemoglobin. No bacteria were isolated from the 12 fish. Additionally, DNA extracts from the liver and spleen of all animals were tested for ISKNV using two conventional polymerase chain reaction (cPCR) assays and two nested PCR (nPCR) assays. ISKNV DNA was amplified in all 12 fish DNA extracts tested, in two or more of the PCR assays. Selected ISKNV amplicons were confirmed by Sanger sequencing. The nucleotide sequences derived from these animals were identical to ISKNV strains previously detected in food (e.g., tilapia and carp) and ornamental species, including strains previously detected in fish from Brazil. To the authors’ knowledge, this is the first report of ISKNV in these native Brazilian cichlids

Association between Zika virus infection and microcephaly in Brazil, January to May, 2016: preliminary report of a case-control study.

BACKGROUND: The microcephaly epidemic, which started in Brazil in 2015, was declared a Public Health Emergency of International Concern by WHO in 2016. We report the preliminary results of a case-control study investigating the association between microcephaly and Zika virus infection during pregnancy. METHODS: We did this case-control study in eight public hospitals in Recife, Brazil. Cases were neonates with microcephaly. Two controls (neonates without microcephaly), matched by expected date of delivery and area of residence, were selected for each case. Serum samples of cases and controls and cerebrospinal fluid samples of cases were tested for Zika virus-specific IgM and by quantitative RT-PCR. Laboratory-confirmed Zika virus infection during pregnancy was defined as detection of Zika virus-specific IgM or a positive RT-PCR result in neonates. Maternal serum samples were tested by plaque reduction neutralisation assay for Zika virus and dengue virus. We estimated crude odds ratios (ORs) and 95% CIs using a median unbiased estimator for binary data in an unconditional logistic regression model. We estimated ORs separately for cases with and without radiological evidence of brain abnormalities. FINDINGS: Between Jan 15, 2016, and May 2, 2016, we prospectively recruited 32 cases and 62 controls. 24 (80%) of 30 mothers of cases had Zika virus infection compared with 39 (64%) of 61 mothers of controls (p=0·12). 13 (41%) of 32 cases and none of 62 controls had laboratory-confirmed Zika virus infection; crude overall OR 55·5 (95% CI 8·6-∞); OR 113·3 (95% CI 14·5-∞) for seven cases with brain abnormalities; and OR 24·7 (95% CI 2·9-∞) for four cases without brain abnormalities. INTERPRETATION: Our data suggest that the microcephaly epidemic is a result of congenital Zika virus infection. We await further data from this ongoing study to assess other potential risk factors and to confirm the strength of association in a larger sample size. FUNDING: Brazilian Ministry of Health, Pan American Health Organization, and Enhancing Research Activity in Epidemic Situations

Association between microcephaly, Zika virus infection, and other risk factors in Brazil: final report of a case-control study.

BACKGROUND: A Zika virus epidemic emerged in northeast Brazil in 2015 and was followed by a striking increase in congenital microcephaly cases, triggering a declaration of an international public health emergency. This is the final report of the first case-control study evaluating the potential causes of microcephaly: congenital Zika virus infection, vaccines, and larvicides. The published preliminary report suggested a strong association between microcephaly and congenital Zika virus infection. METHODS: We did a case-control study in eight public maternity hospitals in Recife, Brazil. Cases were neonates born with microcephaly, defined as a head circumference of 2 SD below the mean. Two controls without microcephaly were matched to each case by expected date of delivery and area of residence. We tested the serum of cases and controls and the CSF of cases for detection of Zika virus genomes with quantitative RT-PCR and for detection of IgM antibodies with capture-IgM ELISA. We also tested maternal serum with plaque reduction neutralisation assays for Zika and dengue viruses. We estimated matched crude and adjusted odds ratios with exact conditional logistic regression to determine the association between microcephaly and Zika virus infection. FINDINGS: We screened neonates born between Jan 15 and Nov 30, 2016, and prospectively recruited 91 cases and 173 controls. In 32 (35%) cases, congenital Zika virus infection was confirmed by laboratory tests and no controls had confirmed Zika virus infections. 69 (83%) of 83 cases with known birthweight were small for gestational age, compared with eight (5%) of 173 controls. The overall matched odds ratio was 73·1 (95% CI 13·0-∞) for microcephaly and Zika virus infection after adjustments. Neither vaccination during pregnancy or use of the larvicide pyriproxyfen was associated with microcephaly. Results of laboratory tests for Zika virus and brain imaging results were available for 79 (87%) cases; within these cases, ten were positive for Zika virus and had cerebral abnormalities, 13 were positive for Zika infection but had no cerebral abnormalities, and 11 were negative for Zika virus but had cerebral abnormalities. INTERPRETATION: The association between microcephaly and congenital Zika virus infection was confirmed. We provide evidence of the absence of an effect of other potential factors, such as exposure to pyriproxyfen or vaccines (tetanus, diphtheria, and acellular pertussis, measles and rubella, or measles, mumps, and rubella) during pregnancy, confirming the findings of an ecological study of pyriproxyfen in Pernambuco and previous studies on the safety of Tdap vaccine administration during pregnancy. FUNDING: Brazilian Ministry of Health, Pan American Health Organization, and Enhancing Research Activity in Epidemic Situations

Zika-related adverse outcomes in a cohort of pregnant women with rash in Pernambuco, Brazil.

BACKGROUND: While Zika virus (ZIKV) is now widely recognized as a teratogen, the frequency and full spectrum of adverse outcomes of congenital ZIKV infection remains incompletely understood. METHODS: Participants in the MERG cohort of pregnant women with rash, recruited from the surveillance system from December/2015-June/2017. Exposure definition was based on a combination of longitudinal data from molecular, serologic (IgM and IgG3) and plaque reduction neutralization tests for ZIKV. Children were evaluated by a team of clinical specialists and by transfontanelle ultrasound and were classified as having microcephaly and/or other signs/symptoms consistent with congenital Zika syndrome (CZS). Risks of adverse outcomes were quantified according to the relative evidence of a ZIKV infection in pregnancy. FINDINGS: 376 women had confirmed and suspected exposure to ZIKV. Among evaluable children born to these mothers, 20% presented with an adverse outcome compatible with exposure to ZIKV during pregnancy. The absolute risk of microcephaly was 2.9% (11/376), of calcifications and/or ventriculomegaly was 7.2% (13/180), of additional neurologic alterations was 5.3% (13/245), of ophthalmologic abnormalities was 7% (15/214), and of dysphagia was 1.8% (4/226). Less than 1% of the children experienced abnormalities across all of the domains simultaneously. Interpretation: Although approximately one-fifth of children with confirmed and suspected exposure to ZIKV in pregnancy presented with at least one abnormality compatible with CZS, the manifestations presented more frequently in isolation than in combination. Due to the rare nature of some outcomes and the possibility of later manifestations, large scale individual participant data meta-analysis and the long-term evaluation of children are imperative to identify the full spectrum of this syndrome and to plan actions to reduce damages

Design and construction of a simplified microwave heating system for high temperature heterogeneous gas-solid reactions

O presente trabalho consistiu no projeto e construção de um sistema simplificado de aquecimento por micro-ondas, destinado à avaliação de catalisadores suportados em materiais que sejam estáveis em temperaturas de 400 a 1.100 ºC e que sejam conversores desta radiação, na frequência de 2,45 GHz, em calor. Tais catalisadores são particularmente interessantes no processo de oligomerização de metano, que requer alta temperatura para sua funcionalização. A sua construção teve como base os modelos encontrados na literatura científica e simulações de funcionamento feitas em computador. Os ajustes e alterações foram feitos a partir dos testes realizados com vários materiais utilizados como suporte para catalisadores. Ao final chegou-se a uma configuração de equipamento cujos testes demonstraram que ele atende satisfatoriamente a seu propósito, tendo possibilitado a avaliação das propriedades de absorção e conversão de micro-ondas em calor de vários materiais, de forma controlada, em toda faixa de temperatura para o qual foi projetado.This work consisted in the design and construction of a simplified microwave heating system, intended to evaluate catalysts supported on stable materials at temperatures from 400 to 1,100 ºC and that convert radiation at 2.45 GHz into heat. Such catalysts are particularly interesting in the methane oligomerization process, which requires high temperature for its functionalization. Its construction was based on models found in the scientific literature and on computer simulations. Adjustments and changes were made from the results of tests carried out with various materials used as support for catalysts. In the end, a configuration of the equipment was obtained, whose tests showed that it meets satisfactorily its purpose, making it possible to evaluate the properties of absorption and conversion of microwaves into heat of several materials, in a controlled way, througout entire temperature range for which it was designed

Despite lacking a formal definition based on synapom...

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Three new species of Proceratophrys Miranda-Ribeiro 1920 from Brazilian Cerrado (Anura, Odontophrynidae)

Brandão, Reuber Albuquerque, Caramaschi, Ulisses, Vaz-Silva, Wilian, Campos, Leandro Ambrósio (2013): Three new species of Proceratophrys Miranda-Ribeiro 1920 from Brazilian Cerrado (Anura, Odontophrynidae). Zootaxa 3750 (4): 321-347, DOI: http://dx.doi.org/10.11646/zootaxa.3750.4.

The use of micro–computed tomography to determine the accuracy of 2 electronic apex locators and anatomic variations affecting their precision

Introduction The aim of this study was to compare the accuracy of 2 electronic apex locators (EALs), Apex ID (SybronEndo, Glendora, CA) and Root ZX (J. Morita, Tokyo, Japan), by means of micro–computed tomographic (micro-CT) imaging and to determine anatomic variations that may affect their accuracy. Methods The root canal length (RCL) and working length (WL) of 33 single-rooted premolars were measured using a visual method, 3-dimensional micro-CT reconstructions, and 2 different EALs. Two different measurements were recorded for each EAL: at the “APEX/0.0” mark and at the “0.5” mark. The WL was determined using 2 different methods: method 1: at the “0.5 mark” of the apex locator and method 2: subtracting 0.5 mm from the “APEX/0.0” mark. The precision of measurements was compared with those recorded by micro-CT imaging. Apical foramen (AF) position and diameter, apical constriction (AC) diameter, distance between the AC and the AF, and the presence/absence of accessory canals were recorded from the micro-CT scans, and their correlation to the accuracy of EALs was determined. Results There was no statistically significant difference in the RCL measurements by any of the different methods. There was a statistically significant difference in the WL recorded by micro-CT imaging compared with those by the visual method and at the “APEX/0.0 mark” − 0.5 mm (P = .031). There was no difference in the measurements acquired by any of the EALs. The “APEX/0.0 mark” − 0.5 mm was less accurate than the “0.5” mark. However, the results were not statistically significant (P > .05). The position of the AF and the AC–AF distance affected the accuracy of the RCL (P = .003) and the “0.5” mark (P = .013). Conclusions Root ZX and Apex ID are equally precise in determining the RCL and WL. The “0.5” mark can be used to determine the WL with high precision. Some anatomic variations may influence the accuracy of EALs

Mechanical resistance of carbon and stainless steel hand instruments used in a reciprocating handpiece

The manual files are still widely used for initial canal negotiation prior the use of nickel-titani-um shaping instruments, to determine working length and to verify patency. A mechanical glide path can be performed using manual files with handpieces, such as M4 Handpiece (SybronEndo, USA) that allows a 30°/30° reciprocating motion. The Pathfinders (SybronEndo, USA) are hand files designed to negotiate complex canals, made from stainless steel (SS) or carbon steel (CS) alloys. The aim of this in vitro study was to compare cyclic fatigue resistance of these two different types of manual Pathfinder instruments used in a M4 reciprocating handpiece in double curved artificial canals. Manual instruments designed for glide path (size #9 ISO .02 taper) made from different alloys were selected: Group SS - stainless steel Pathfinders (Sybron Endo) and Group CS - carbon steel Pathfinders size K2 (Sybron Endo). Ten instruments of each group were tested for resistance to cyclic fatigue with a reciprocating M4 handpiece inside an artificial S-shaped canal; the time to fracture was recorded for each file and data were statistically analyzed (ANOVA). Mean values (and SD) were 527 (± 89) seconds for the CS instruments and 548 (± 104) seconds for the SS files. No significant differences were observed between groups (p=0,062). According to the results, both carbon and stainless steel instruments presented similar fatigue resistance when used with M4 reciprocating handpiece in double curved canals