438 research outputs found

    Avaliação do processo de extração do cobre e prata contidos em placas de circuito impresso via lixiviação ácida e recuperação por oxirredução / Evaluation of the copper and silver extraction process in printed circuit boards via acid lixiviation and oxirreduction recovery

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    O acentuado crescimento do setor industrial eletrônico ocasiona, ao mesmo tempo, o crescimento dos resíduos de equipamentos eletrônicos, tanto industriais quanto domésticos como, por exemplo, o descarte de equipamentos obsoletos. Esses resíduos eletrônicos por sua vez podem ser reciclados e os metais neles contidos, recuperados, possibilitando redução no impacto ambiental gerado pelo seu descarte inadequado, além de promover economia na exploração das reservas naturais. Dentro desse contexto, o presente trabalho, avaliou a recuperação do cobre e da prata a partir de placas de circuito impresso de equipamentos eletrônicos por meio de processos físicos e químicos, reduzindo o tamanho das placas e posteriormente realizando a lixiviação em meio ácido, utilizando ácido nítrico diluído, tendo como resultado uma lixiviação acima de 75% do cobre e 90% da prata contidos nas placas. Esses metais solubilizados foram recuperados com técnica de oxirredução, utilizando ferro metálico, possibilitando a recuperação acima de 90% do cobre e 99% da prata emsolução. Para quantificar os metais em solução e o recuperado foi utilizada a técnica de espectrofotometria de absorção atômica.   

    Anthelmintic activity of Annona crassiflora leaves against Haemonchus contortus: part 1: in vitro inhibition of the hatchability and larval development

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    We evaluated the activity of Annona crassiflora leaves against Haemonchus contortus resistant to albendazol.  Aqueous (AE), ethanolic (EE) and ethyl acetate (EAE) extracts were produced and the predominant presence of flavonoids was observed in HPLC-DAD chromatograms. Initially we evaluated the larval development inhibition (LDI) of dry A. crassiflora leaf powder or its AE directly in fecal quantitative cultures. The efficacies of the extracts, with or without tannins, on egg hatching inhibition (EHI) were investigated reveling that the EE was the most effective (LC90 = 8.96 mg/mL). However, after tannin removal, AE showed the highest activity (LC90 = 4.27 mg/mL). In the LDI test, the LC90 of AE was < 6.25 mg/g of fecal culture and to leaf powder of leaves was 69.14 mg/g.  High efficacies of AE and EE for EHI were detected and the tannins were not the main active metabolites. The anthelmintic potential of this plant could be attributed to association between flavonoids and other metabolites

    Anthelmintic activity of Annona crassiflora leaves against Haemonchus contortus: part 2: efficacy in vivo and blood parameters

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    In this study we evaluated the oral toxicity of leaf extracts of Annona crassiflora of for mice and the blood and parasitological parameters of lambs experimentally infected with Haemonchus contortus and treated with leaves of this plant. The highest dose of AE (aqueous extract) administered to mice (203.0 mg/kg bw) was well tolerated, suggesting low toxicity. At necropsy, macroscopic examination revealed no abnormalities of the evaluated viscera.  Lambs infected with the nematode were divided one group treated with leaf powder and a control group that did not treat. Split-plot design analysis was performed where the treatments were defined as plots and three periods of collection were defined as subplots. Similar performances to weight gain were observed among the lamb groups. The oral administration of leaf powder at 2.75g /Kg bw did not alter the physiological blood parameters in comparison to untreated lambs; however, this dose was not efficient to fecal egg reduction.    We consider that other formulations and administration protocols should be evaluated to promote an effective alternative control using the leaves of this plant

    Análise bacteriológica de músculo e gônadas de vieira, Nodipecten nodosus (Mollusca: Bivalvia), congelados e irradiados

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    No presente trabalho foram analisadas amostras de músculo e gônadas de vieira crus e congelados, oriunda de maricultura de Angra dos Reis, Rio de Janeiro, Brasil. Esta pesquisa teve como finalidade a verificação da eficiência da irradiação, utilizando-se doses de 2kGy e 5kGy. Na Contagem de Bactérias Heterotróficas Aeróbias Mesófilas (CBHAM) observou-se diferença estatisticamente significativa do grupo controle em relação ao grupo irradiado a 5kGy; enquanto que para a Contagem de Bactérias Heterotróficas Aeróbias Psicrotróficas (CBHAP) não se observou nenhuma diferença estatisticamente significativa entre os grupos avaliados. O Número Mais Provável (NMP) de Enterococcus spp. não teve sua presença evidenciada em nenhuma das amostras analisadas. Conclui-se que a irradiação, nesta pesquisa, foi eficiente somente para bactérias mesófilas na dose de 5kGy.The present article investigated the effectiveness of irradiation process to conservate frozen raw scallops’ muscle and gonads. Samples of this animal were collected from cultivated areas at Angra dos Reis, Rio de Janeiro state, Brazil. The samples were submitted to treatment of 2 and 5 kGy doses. Mesophilic Aerobic Heterotrophic Bacteria Count showed a statistically significant difference from the control group related to the 5kGy one, while for the Heterotrophic Bacteria Aerobic Psychrotrophic Count were not observed any statistically significant difference among the analysed groups. The Most Probable Number of Enterococcus spp. was not evident in any of the samples. It was concluded that irradiation was effective only for mesophilic bacteria using the 5kGy dose in this research

    Diagnóstico e tratamento da sinostose radioulnar proximal bilateral: relato de caso: Diagnosis and treatment of bilateral proximal radioulnar synostosis: case report

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    O autor discorre um caso de uma criança do sexo masculino portadora de sinostose radioulnar proximal bilateral. Foi realizada revisão da literatura e são comentados mecanismos de diagnóstico e possibilidades de tratamento da patologia

    Surto policlonal de infecção de corrente sanguínea causada pelo complexo Burkholderia cepacia em unidades de hospital-dia de hematologia e transplante de medula óssea

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    Aim: The objective was to describe an outbreak of bloodstream infections by Burkholderia cepacia complex (Bcc) in bone marrow transplant and hematology outpatients. Methods: On February 15, 2008 a Bcc outbreak was suspected. 24 cases were identified. Demographic and clinical data were evaluated. Environment and healthcare workers' (HCW) hands were cultured. Species were determined and typed. Reinforcement of hand hygiene, central venous catheter (CVC) care, infusion therapy, and maintenance of laminar flow cabinet were undertaken. 16 different HCWs had cared for the CVCs. Multi-dose heparin and saline were prepared on counter common to both units. Findings: 14 patients had B. multivorans (one patient had also B. cenopacia), six non-multivorans Bcc and one did not belong to Bcc. Clone A B. multivorans occurred in 12 patients (from Hematology); in 10 their CVC had been used on February 11/12. Environmental and HCW cultures were negative. All patients were treated with meropenem, and ceftazidime lock-therapy. Eight patients (30%) were hospitalized. No deaths occurred. After control measures (multidose vial for single patient; CVC lock with ceftazidime; cleaning of laminar flow cabinet; hand hygiene improvement; use of cabinet to store prepared medication), no new cases occurred. Conclusions: This polyclonal outbreak may be explained by a common source containing multiple species of Bcc, maybe the laminar flow cabinet common to both units. There may have been contamination by B. multivorans (clone A) of multi-dose vials.O objetivo foi descrever um surto de infecções da corrente sanguínea por complexo B. cepacia (Bcc) nos ambulatórios de hematologia e transplante de medula óssea. Métodos: Em 15/02/2008, um surto de Bcc foi suspeitado. 24 casos foram identificados. Os dados demográficos e clínicos foram avaliados. Mãos de profissionais da saúde e ambiente foram cultivadas. Espécies foram determinadas e tipadas. Reforço da higiene das mãos, cuidados com cateteres, terapia de infusão e manutenção da câmara de fluxo laminar foram realizadas. 16 profissionais de saúde (PS) diferentes manipularam os cateteres. Heparina multidoses e soro eram preparadas em um balcão comum a ambas as unidades. Resultados: 14 pacientes tiveram B. multivorans (um paciente teve também B. cenopacia), 6 Bcc não-multivorans e um teve um agente não pertencente a Bcc. Clone A de B. multivorans ocorreu em 12 pacientes (da Hematologia), em 10 o cateter havia sido utilizado nos dias 11 ou 12 de fevereiro. Culturas ambientais e de PS foram negativos. Todos os pacientes foram tratados com meropenem e selo de ceftazidima. Oito pacientes (30%) foram hospitalizados. Não ocorreram mortes. Após as medidas de controle, nenhum novo caso ocorreu. Conclusões: Este surto policlonal pode ser explicado por uma fonte comum contendo várias espécies de Bcc, talvez a câmara de fluxo laminar comum a ambas as unidades. Pode ter havido contaminação por B. multivorans (clone A) de frascos multi-dose

    Effects of Aqueous Extracts of Caryocar brasiliense in Mice

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    Background: Caryocar brasiliense Cambess (Caryocaraceae) is an arboreal plant native of Brasilian Cerrado and its fruit is an important source of food and income for the human population of this region. In addition to using as food, different parts of this tree have great medicinal potential as antimicrobial, anti-inflammatory, antioxidant and antihelmintic. However, the active metabolites those are likely to confer these pharmacological properties healing may also be toxic dependent upon the dose and route of administration. In this quest, the aim of this study was to assess the acute toxicity of aqueous extracts of fruit peels and leaves of C. brasiliense in mice of both genders.Materials, Methods & Results: The aqueous extracts were obtained by decoction, diluted in water and filtered through membrane. The toxicity of extract of fruit peels (62.5 at 500 mg/kg of body weight (BW) and leaf extract (18.75 mg/kg bw) were evaluated in males and  females mice (Mus musculus) Swiss by intraperitoneal route. For 2 control groups were administered injection water. The clinical signs and deaths were recorded up to 14 days after administration. The lethal doses for 10 (LD10) or 50 (LD50) % of population were estimated with Probit regression analysis. The Chi-square test was used to analyze differences of mortality frequencies between males and females. The groups treated with the two lower doses of both extracts completely abolished the clinical alteration between two and four hours after inoculation. The comportment of control group’s animals was normalized immediately after administration of injection water. The higher dose administered in both experiments were lethal for all animals, but the doses 250 mg/kg BW of fruit peels extract and 150 mg/kg  of BW of leaves extract caused mortality of 100% just in males.  However, in both experiments there were no significant differences between the mortality frequency for groups of male and female, as well the comportment of these animals when these doses were administered. Dose-dependent response was observed to mortality. The LD10 corresponded to 89.6 mg/kg BW and LD50 was 149.8 mg/kg BW for fruit peel extract. For the leaf extract , LD10 and LD50 were 33.35 and 67.01 mg/kg BW, respectively.Discussion: Aqueous extracts of the fruit peels and leaves of C. brasiliense were classified as very toxic since the LD50 ranged from 50 to 500 mg / kg BW. For both extracts, similar behavioral changes were observed. Among the secondary metabolites present in fruit peel and leaves, saponins and tannins can promote nervous symptoms. Although there are no records in the literature about animals and human orally intoxicated with any part of C. brasiliense, the development of specific studies to determine its toxicity is relevant, considering the social and ecological importance of this plant

    Desenvolvimento e avaliação sensorial de pão de forma adicionado da farinha do resíduo da graviola

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    Bread is a product widely consumed since ancient times, so many scholars seek to create new formulations that give them more flavor and nutritional quality through the full reuse of food. Soursop is rich in minerals such as calcium, potassium, magnesium and vitamins (A, B and C). Thus, the objective was to elaborate loaves of bread added with different concentrations of soursop residue flour, as well as to evaluate the sensory characteristics of the elaborated products. Initially the soursop peels were dried in a 60 ° C circulating oven for 24 hours and then flour was obtained. Then different formulations of loaves of bread were prepared: PFC (0% soursop residue flour), PF10% (10% soursop residue flour) and PF20% (20% soursop residue flour). Sensory analysis was performed using the affective test with a nine-point structured hedonic scale and the purchase intention test. From the results, it was inferred that in the sensory analysis, the PFC sample had an acceptability higher than 80% for all evaluated attributes, while the PF10% bread had an acceptability index higher than 73% and the PF20% bread reached acceptability index. over 66% for all appreciated attributes. Therefore, it was found that it is possible to partially replace wheat flour with soursop residue flour in the production of loaf breads, since PF10% was not affected by the addition of flour.El pan es un producto ampliamente consumido desde la antigüedad, por lo que muchos académicos buscan crear nuevas formulaciones que les den más sabor y calidad nutricional a través de la reutilización completa de los alimentos. La guanábana es rica en minerales como calcio, potasio, magnesio y vitaminas (A, B y C). Por lo tanto, el objetivo era elaborar barras de pan añadidas con diferentes concentraciones de harina de residuos de guanábana, así como evaluar las características sensoriales de los productos elaborados. Inicialmente, las cáscaras de guanábana se secaron en un horno de circulación a 60 ° C durante 24 horas y luego se obtuvo harina. Luego se prepararon diferentes formulaciones de barras de pan: PFC (0% de harina de residuos de guanábana), PF10% (10% de harina de residuos de guanábana) y PF20% (20% de harina de residuos de guanábana). El análisis sensorial se realizó mediante la prueba afectiva con una escala hedónica estructurada de nueve puntos y la prueba de intención de compra. A partir de los resultados, se infirió que en el análisis sensorial, la muestra de PFC tenía una aceptabilidad superior al 80% para todos los atributos evaluados, mientras que el pan PF10% tenía un índice de aceptabilidad superior al 73% y el pan PF20% alcanzó un índice de aceptabilidad. más del 66% para todos los atributos apreciados. Por lo tanto, se descubrió que es posible reemplazar parcialmente la harina de trigo con harina de residuos de guanábana en la producción de pan de molde, ya que el PF10% no se vio afectado por la adición de harina.O pão é um produto amplamente consumido desde os tempos mais remotos, por isso diversos estudiosos buscam criar novas formulações que lhes confiram mais sabor e qualidade nutricional através do reaproveitamento integral dos alimentos. A graviola é rica em sais minerais, como cálcio, potássio, magnésio e vitaminas (A, B e C). Assim, objetivou-se elaborar pães de forma adicionados de diferentes concentrações da farinha do resíduo da graviola, bem como avaliar as características sensoriais dos produtos elaborados. Inicialmente as cascas da graviola foram secas em estufa de circulação de ar a 60° durante 24 horas e após foi obtida a farinha. Em seguida, foram elaboradas diferentes formulações de pães de forma: PFC (0% de farinha do resíduo da graviola), PF10% (10% de farinha do resíduo da graviola) e PF20% (20% da farinha do resíduo da graviola). A análise sensorial foi realizada através do teste afetivo com escala hedônica estruturada de nove pontos e teste de intenção de compra. Diante dos resultados, inferiu-se que na análise sensorial, a amostra PFC obteve aceitabilidade superior a 80% para todos os atributos avaliados, enquanto que o pão PF10% apresentou índice de aceitabilidade superior a 73% e o pão PF20% alcançou índice de aceitabilidade acima de 66% para todos atributos apreciados. Diante disso, constatou-se que é possível substituir parcialmente a farinha de trigo por farinha do resíduo da graviola na produção de pães tipo forma, visto que o PF10% não teve a sua aceitabilidade afetada em razão a adição da farinha

    Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

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    The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration
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