Abstract Fiber-reinforced polymers are materials used to recover/strengthen reinforced concrete structures load capacity. This material exhibits good mechanical properties with low self-weight. This work performed a series of nonlinear finite element analyses in one-way (OW) wall panels with a central cut-out opening, strengthened using carbon fiber-reinforced polymer (CFRP). The experimental tests conducted by Mohammed et al. (2013) were used as a benchmark. The numerical simulations were carried out in the commercial code ATENA, in which the material and geometrical nonlinearities were accounted. As a result, the numerical models reasonably predicted the ultimate load of the walls, and all models presented a crack pattern similar to the experimental tests, verifying that the CFRP addition caused a more distributed crack pattern. The results obtained in this work revealed that CFRP strengthening caused 24-50% enhancement of the ultimate load. Additional models were carried out to extend the numerical results and proposed a new equation that can be used to predict the ultimate load of OW walls with and without CFRP strengthening.

Foi desenvolvida uma pesquisa no CNPMS (Embrapa) objetivando quantificar a influência das variáveis micrometeorológicas no crescimento e desenvolvimento do milho BR 106 cultivado via sementeira direta e condições de rega. Foi utilizado um anemómetro sónico tridimensional para a medição dos fluxos de CO2 acima da canópia. O crescimento do BR 106 foi afetado pelas variações do microclima da canópia, com grandes períodos de nebulosidade, diminuição do potencial de vapor na atmosfera e maior conteúdo de energia, principalmente luz e temperatura do ar, contribuindo para os valores máximos dos atributos de crescimento no período P2 (Florescimento). Contudo, a senescência das folhas do terço médio inferior foi mais expressiva na transição do P2 para o P3 (Embonecamento), houve aumento da razão da área foliar e da área foliar específica, além de redução da razão de massa foliar, que induziram a queda de 13% na assimilação do CO2 no período reprodutivo. Esse comportamento não afetou o rendimento final da variedade que apresentou um valor próximo do potencial máximo.

Research was conducted in CNPMS (Embrapa), Sete Lagoas-MG, to quantify the influence of micrometeorological variables on growth and development in the canopy of a maize crop variety BR 106 under no-tillage in irrigated conditions. The flow of CO2 was measured above the canopy using a system that comprises a three-dimensional sonic anemometer. The growth of BR 106 was affected by changing in the canopy’s microclimate, with extended periods of cloudiness, reducing the vapor potential in the atmosphere and higher content of energy, especially light and air temperature, contributing to the maximum values of the attributes of growth present in P2 (12 leaves to flowering). However, the senescence of lower leaves of canopy, in the transition from P2 to P3 (beginning of grain formation), increased the RLA (relation leaf area) and SLA (specific leaf area), and reduce the RLM (rate leaf matter), dependent on LAI (leaf area index) and NAR (net assimilation rate), which led to a decrease of 13% the assimilation of CO2 over the reproductive period. This behavior did not affect the final yield of the variety that showed a value close to potential.

In this study, we developed a method for the visual detection of biodiesel in petrodiesel-biodiesel (BX) blends through the aminolysis of the methyl or ethyl esters of fatty acids that are found in biodiesel and that are absent from diesel and vegetable oils. This method is based on three reactional stages, which produce a dark red and easily visualized complex in the presence of biodiesel. In the absence of biodiesel, there is no dark red coloring, whereas in the presence of diesel or vegetable oil, there is a light red to yellow coloring. This simple, practical, inexpensive, and effective procedure may be applied by petrol stations to guarantee to consumers and resellers the presence of biodiesel in diesel blends, regardless of the BX blend's initial coloring or of the sulfur found in the diesel. In short, it ensures a safe fuel tank fill-up with BX blend.

Parâmetros que influenciam a eficiência da degradação do glifosato (adição única de Fe2+, adição simultânea de Fe2+ e Fe3+ numa razão molar de 1:1 (Fe2+/Fe3+), adição de íons oxalato e de H2O2) foram avaliados em escala de laboratório. Efeitos sinérgicos sobre a degradação e formação de fosfato foram observados utilizando a adição simultânea de Fe2+/Fe3+, bem como adicionando oxalato. Por outro lado, aumentos nas concentrações de Fe2+/Fe3+, oxalato e H2O2 não proporcionaram incremento linear da mineralização de glifosato e liberação de fosfato. Utilizando concentrações elevadas dessas espécies, a eficiência de mineralização de glifosato e de liberação de fosfato foi constante ou até mesmo reduzida. Sob condições otimizadas (0,27 mmol L-1 de Fe2+/Fe3+; 1,13 mmol L-1 de oxalato e 10,3 mmol L-1 de H2O2), os resultados obtidos em escala laboratorial e de planta piloto solar foram próximos. Uma relação direta entre a redução da toxicidade e concentração de glifosato também foi observada.

Parameters that influence the efficiency of the degradation of glyphosate (addition of Fe2+, simultaneous addition of Fe2+ and Fe3+ at a 1:1 (Fe2+/Fe3+) molar ratio, addition of oxalate and of H2O2) were evaluated at lab-scale. Synergic effects on its degradation and release of phosphate were observed using Fe2+/Fe3+, as well as adding oxalate. On the other hand, the concentration increase of Fe2+/Fe3+, oxalate and H2O2 did not promote a linear increase of glyphosate mineralization and release of phosphate. Using high concentrations of these species, the efficiency of glyphosate mineralization and release of phosphate was constant or even decreased. Under optimized conditions (0.27 mmol L-1 of Fe2+/Fe3+; 1.13 mmol L-1 of oxalate and 10.3 mmol L-1 of H2O2), close results for mineralization and release of phosphate were obtained in lab-scale and using a solar pilot plant. A direct ratio between reducing the toxicity and glyphosate concentration was also observed.

A simple, precise, specific, repeatable and discriminating dissolution test for primaquine (PQ) matrix tablets was developed and validated according to ICH and FDA guidelines. Two UV assaying methods were validated for determination of PQ released in 0.1 M hydrochloric acid and water media. Both methods were linear (R²>0.999), precise (R.S.D.<1.87%) and accurate (97.65-99.97%). Dissolution efficiency (69-88%) and equivalence of formulations (f2) was assessed in different media and apparatuses (basket/100 rpm and paddle/50 rpm) tested. Discriminating condition was 900 mL aqueous medium, basket at 100 rpm and sampling times at 1, 4 and 8 h. Repeatability (R.S.D.<2.71%) and intermediate precision (R.S.D.<2.06%) of dissolution method were satisfactory.

Objetivou-se com este trabalho avaliar o crescimento e produção da mamoneira (Ricinus communis L., cv. BRS Energia) cultivada em regime de sequeiro em função da adubação combinada de casca de mamona na forma moída e natural com doses crescentes de fertilizante nitrogenado. O experimento foi realizado entre setembro de 2009 a março de 2010, no Campus IV/UEPB. Realizou-se o plantio em vasos plásticos de 60 L preenchidos com 58 kg de solo. Utilizou-se o delineamento de blocos ao acaso em arranjo fatorial 2 x 4, sendo aplicado 3 t ha-¹ de casca de mamona em duas formas de utilização (natural e moída) e quatro doses de nitrogênio (0, 30, 60, 90 kg ha-¹), com quatro repetições totalizando 32 parcelas. Verifica-se que a adubação com a casca moída foi superior a casca natural. Para a massa seca do cacho, área foliar por planta e número de folhas a dosagem 90 kg ha-¹ de N foi superior às demais. Já para o número de nós foi a dose de 60 kg ha-¹ de N. A casca de mamona usada de forma racional, como adubo, contribui para redução de custos ao produtor e incrementos na fertilidade do solo.

The objective of this research was to evaluate the growth and production of castor bean (Ricinus communis L.) BRS Energia in rainfed cultivation under combined fertilization of castor bean bark in a natural and ground forms and with increasing levels of nitrogen. The experiment was conducted during September, 2009 to March, 2010, at Campus IV/UEPB. The planting was done in 60 L pots filled with 58 kg of soil. Using a randomized block design in a 2 x 4 factorial, with two kinds of bark of castor bean (natural and ground) in the dose of 3 t ha-¹ and four rates of nitrogen (0, 30, 60, 90 kg ha-¹) with four replications. It was verified that fertilization with the ground bark was superior than natural bark. For the dry mass of the bunch, leaf area per plant, and leaf number, dose of 90 kg ha-¹ of N was better than the others. While for the number of nodes the dose of 60 kg ha-¹ of N was better. The bark of castor bean used in a rational way, as fertilizer, contributes to reduce cost of production and increases the soil fertility.

The present work consists of the development and validation of analytical method for evaluation of glycyrrhizic acid, salicylic acid, and caffeine in chitosan-alginate nanoparticles by high performance liquid chromatography. Method validation investigated parameters such as linearity, precision, accuracy, robustness and specificity, which gave results within the acceptable range. The methods were applied to nanoparticles suspensions containing the drugs and were able to determine the entrapment efficiency successfully. The best entrapment efficiency was achieved with the glycyrrhizic acid (95.4%).

Many routes for extracting silica from rice hulls are based on direct calcining. These methods, though, often produce silica contaminated with inorganic impurities. This work presents the study of a strategy for obtaining silica from rice hulls with a purity level adequate for applications in electronics. The technique is based on two leaching steps, using respectively aqua regia and Piranha solutions, which extract the organic matrix and inorganic impurities. The material was characterized by Fourier-transform infrared spectroscopy (FTIR), powder x-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy (SEM), particle size analysis by laser diffraction (LPSA) and thermal analysis.

OBJETIVO: Avaliar os efeitos na função ventricular esquerda do uso precoce e tardio de dopamina, em modelo experimental de coração isolado. MÉTODO: Foram utilizados 60 coelhos em modelo de coração isolado mantido por animal suporte. Um balão intraventricular foi locado no ventrículo esquerdo. Três grupos foram constituídos: grupo controle (GC); grupo que recebeu dopamina precoce (Dopa P) e grupo que recebeu dopamina tardia (após 20 minutos) (Dopa T). Foram realizadas leituras hemodinâmicas diretas e indiretas. RESULTADOS: Fluxo sangüíneo coronariano: GC(7,196 ± 1,275ml/min); Dopa P (9,477 ± 1,160ml/min); Dopa T (14,316 ± 2,308ml/min), com GC=Dopa P, GC ¹Dopa T e Dopa P¹Dopa T. Primeira derivada temporal da pressão intraventricular (dp/dt+): GC (719,61 ± 127,53ml/min); Dopa P (719,61 ± 127,53ml/min); Dopa T (1431,60 ± 230,87ml/min), p<0,05, Dopa P¹Dopa T, GC=Dopa P e GC ¹ Dopa T. Primeira derivada temporal da pressão intraventricular negativa (dp/dt-): GC (469,85 ± 107,16mmHg/s); Dopa P (716,07 ± 215,66mmHg/s); Dopa T (931,24 ± 181,46mmHg/s), p<0,05, Dopa P¹Dopa T¹GC. Delta V: GC (1,355 ± 0,2432ml); Dopa P (0,97 ± 0,3199ml); Dopa T (1,27 ± 0,2983ml), p>0,05, Dopa P=Dopa T=GC. Estresse sistólico desenvolvido: GC (27,273 ± 10,276g/cm²); Dopa P (55,219 ± 24,625g/cm²); Dopa T (79,152 ± 12,166g/cm²), Dopa P=Dopa T, Dopa P=GC e GC ¹ Dopa T.Dialdeído Malônico (MDA): GC (4,5 ± 0,527mmol/L); Dopa P (4,7 ± 1,16mmol/L); Dopa T (4,1 ± 0,7379mmol/L), p>0,05, Dopa P=Dopa T=GC. CONCLUSÕES: Concluiu-se que, no modelo experimental delineado, o uso precoce da dopamina foi deletério, segundo algumas variáveis hemodinâmicas.

OBJECTIVE: To evaluate the effect on the left ventricular function of the early and late use of dopamine in an experimental model of an isolated heart. METHOD: Were used 60 rabbits in an isolated heart model sustained by animal support. An intraventricular balloon was placed in the left ventricle. Three groups were constituted: a control group (CG); a group that received dopamine precociously (Dopa P) and a group that received dopamine after 20 minutes (Dopa T). Direct and indirect hemodynamic readings were taken. RESULTS: Coronary artery flow: CG (7.196 ± 1.275 mL/min); Dopa P (9.477 ± 1.160 mL/min); Dopa T (14.316 ± 2.308 mL/min), with CG = Dopa P, CG ¹ Dopa T and Dopa P ¹ Dopa T. First intraventricular positive derivative of the pressure (dp/dt+): CG (719.61 ± 127.53 mmHg/s); Dopa P (719.61 ± 127.53 mmHg/s); Dopa T (1431.60 ± 230.87 mmHg/s), p<0.05, Dopa P¹Dopa T, CG=Dopa P and CG ¹ Dopa T. First intraventricular negative derivative of the pressure (dp/dt -): CG (469.85 ± 107.16 mmHg/s); Dopa P (716.07 ± 215.66 mmHg/s); Dopa T (931.24 ± 181.46 mmHg/s), p<0.05, Dopa P¹Dopa T¹CG. Delta V: CG (1.355 ± 0.2432 mL); Dopa P (0.97 ± 0.3199 mL); Dopa T (1.27 ± 0.2983 mL), p>0.05, Dopa P = Dopa T = CG. Developed systolic stress: CG (27.273 ± 10.276 g/cm²); Dopa P (55.219 ± 24.625 g/cm²); Dopa T (79.152 ± 12.166 g/cm²), Dopa P=Dopa T, Dopa P = CG and CG ¹ Dopa T. Malonic Dialdehyde (MDA): CG (4.5 ± 0.527 mmol/L); Dopa P (4.7 ± 1.16 mmol/L); Dopa T (4.1 ± 0.7379 mmol/L), p>0.05, Dopa P=Dopa T=CG. CONCLUSION: We concluded that, in the delineated experimental model, the early use of the dopamine was deleterious as shown by some hemodynamic variables.

OBJETIVO: Analisar, comparativamente, a obtenção minimamente invasiva com o uso do MINI-HARVEST® e com instrumental tradicional adaptado. MÉTODO: De junho de 1996 a janeiro de 1999, 63 pacientes submetidos à cirurgia de revascularização do miocárdio tiveram suas veias safenas retiradas segundo técnica minimamente invasiva. Nos 30 primeiros pacientes da série utilizou-se método de visão direta com auxílio de dois afastadores de Langenbeck, e nos 33 restantes utilizou-se o MINI-HARVEST®. RESULTADOS: A idade média dos pacientes era de 61 ± 8,75 anos, sendo 52 homens e 11 mulheres. Quarenta e cinco pacientes eram diabéticos, 45 apresentavam sobrepeso/obesidade, 25 eram tabagistas ativos, 32 apresentavam história pregressa de infarto do miocárdio. O tempo médio de retirada da veia safena com afastadores Langenbeck foi de 34,2 ± 8,14 minutos e com o MINI-HARVEST® de 39,20 ± 9,12 minutos. A extensão de veia retirada foi similar nos dois grupos, variando de 10 a 30 cm. Houve uma deiscência superficial no grupo com afastadores de Langenbeck. Houve necessidade de reversão para método tradicional de retirada em dois casos do grupo MINI-HARVEST® e um do grupo Langenbeck. A incidência de infarto transoperatório foi 4,5% (três) no grupo Langenbeck e 3,1%(dois) no grupo MINI-HARVEST®. CONCLUSÕES: Podemos concluir que o método de obtenção de veia safena minimamente invasivo sob visão direta é efetivo e seguro, tanto com o uso de instrumentos tradicionais adaptados para este fim, como com afastadores especialmente constituídos, ressaltando-se que o MINI-HARVEST® dispensa a presença de um auxiliar.

OBJECTIVE: To comparatively analyze minimally invasive procurement of saphenous veins using Mini-Harvest® system and a technique using adapted traditional instruments. METHOD: From June 1996 to January 1999, 63 patients who were submitted to Coronary Artery Bypass Grafting Surgery had their saphenous veins resected using minimally invasive techniques. In the first 30 patients of the series, a direct visualization method employing two Langenbeck's retractors was utilized and for the 33 remaining patients the Mini-Harvest® technique was utilized. RESULTS: The mean age of the patients was 61 ± 8.75 years old. Fifty-two patients were male and 11 female. Forty-five patients were diabetics, 45 were overweight or obese, 25 were smokers and 32 presented history of myocardial infarction. The mean time to resect the saphenous vein using the Langenbeck's retractors was 34.2 ± 8.14 minutes and using the Mini-Harvest® it was 39.20 ± 9.12 minutes. The lenghts of the extracted veins were similar in both groups, varying between 10 and 30 cm. There was one case of superficial dehiscence in the Langenbeck group. With two patients in the Mini-Harvest® group and one in Langenbeck's group it was necessary to revert to the traditional method of procurement. The incidence of tran-soperative infarction was 4.5% (three patients) in Langenbeck's group and 3.1% (two patients) in the Mini-Harvest® group. CONCLUSIONS: We can conclude that the minimally invasive procurement methods of the saphenous vein by direct visualization are effective and safe, both when employing adapted traditional instruments and using purpose-made retractors. We stress, however, that the Mini-Harvest® method does not require an assistant.

O presente estudo teve por objetivo padronizar modelo experimental de estimulação cardíaca artificial atrial em coelhos. Foram utilizados 20 coelhos raça Norfolk-2000 de ambos os sexos com peso mínimo de 2200g. Após anestesia endovenosa com pentobarbital(30mg/Kg), foi dissecada a veia jugular externa esquerda e introduzido eletrodo Ethicon<FONT FACE="Symbol">Ò</font> especialmente preparado, até átrio direito via veia cava esquerda. Foram realizadas leituras dos parâmetros elétricos(ondaP, resistência e limiar de comando) no ato cirúrgico e com 7, 14 e 21 dias denominados M1,M2, M3 e M4 respectivamente. Observamos diferença significativa em todos as variáveis analisadas entre M1 e demais momentos. Os resultados são compatíveis com o que se conhece de estimulação cardíaca artificial em outras espécies animais e no homem. O presente modelo mostrou ser viável para estudos de estimulação cardíaca artificial.

The aim of the present study was to standardize an experimental model for artificial atrial heart pacing in rabbits. Twenty rabbits(Norfolk-2000, both sexes with minimum weigth of 2200g) were studied. After endovenous anesthesia with pentobarbital sodium(30mg/Kg) the external jugular vein was dissected and a pacemaker lead(Ethicon<FONT FACE="Symbol">â</font> ) was introduced through left cava vein until the rigth atriun. The eletric parameters(P wave, resistance and threshold) were accomplished at surgical time and at 7, 14 and 21 post-operative day. These experimental moments were denominated M1, M2, M3 and M4 respectively. The statistical analisys showed significant difference between M1 and all others experimental moments. The results are compatible with the actual knowlodge of artificial heart pacing in others animal species and in human beings. The present model showed to be viable for artificial pacing studies.