Influência de diferentes métodos de limpeza sobre a eficiência de corte e as características morfológicas de fresas Carbide

Introduction: Currently, there are many questions regarding the cleaning methods seeking greater efficiency and less loss of burs. Aim: the aim of this study was to evaluate the influence of cleaning methods on the cutting efficiency and morphological characteristics of stainless steel burs tungsten carbide (carbide). Materials and method: Thirty burs were divided into five groups (n = 5) according with the cleaning method: L1 - steel brush, L2 - nylon brush, L3 - ultrasound  +  distilled water, L4 - ultrasound + descaling solution and L5 - no cleaning method (control). The burs were used for the cutting of bovine enamel during six periods of 12 minutes each. After each period, the burs were cleaned (except L5 ) following the protocol established for each group. The cutting efficiency was determined by mass loss and morphological characteristics. Result: The average amount of wear after 72 minutes of use were L1  = 0.3558 g; L2  = 0.4275 g; L3  = 0.4652 g; L4  = 0.4396 g e L5  = 0.4854 g; significant differences in the time of use (p  <  0.001) and cleaning method (p  <  0.001). The L1 group showed the worst performance. Regardless of the experimental group, morphological analysis revealed alterations in the cutting blades soon after the first 12 minutes, being L1 the most affected group. Conclusion: The cleaning with wire brush was the most damaging method to the cutting efficiency and to the morphology of carbide burs.

Avaliação da eficácia de limpeza de quatro agulhas irrigadoras endodônticas

The irrigation of root canals aims to their cleaning and disinfection, improving endodontic treatment success. OBJECTIVE: To investigate the influence of the diameter and type of irrigation needle and the root canal enlargement on the mechanical efficacy of endodontic irrigation. MATERIAL AND METHODS: Twelve human single-rooted mandibular incisors were used. During some instrumentation stages (enlargement by #20, #30, and #40 K file), root canals were filled with radiographic contrast solution mixed to propyleneglycol and zinc oxide. Needles with different diameters and designs were employed: G1 – 23G and lateral opening; G2 – 22G and apical opening; G3 – 30G and lateral opening; G4 – 30G and apical opening. The needles were inserted up to resistance, with 1 mm step-back to avoid root canal obliteration. The irrigation was performed with 2 mL of distilled water. Before and after irrigation/aspiration, teeth were radiographed at bucco-lingual and mesiodistal direction, using a digital radiographic system. Then, root canal areas, before (filled by contrast solution) and after irrigation (remnant of contrast solution), were submitted to image subtraction with Adobe Photoshop CS4 software. Subsequently, the areas were measured by Image Tool 3.0 software, allowing the obtaining of the cleaning percentage for each modality. Data were analysed by using Anova and Tukey's test. The level of significance was set at P < 0.05. RESULTS: For all root canal enlargements, 30G needles (G3 e G4) presented a better cleaning efficacy. In all groups, higher cleaning efficacy percentage was observed at #30 and #40 K file enlargement. CONCLUSION: Regardless their design, thinner needles were more effective; a better cleaning efficacy occurred in more enlarged root canals.

Influência do diâmetro foraminal do canal radicular, do tipo e da penetração de agulha, e do fluxo da solução irrigadora na limpeza e na extrusão apical

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

O ensino da metodologia projetual no desenvolvimento de produtos de moda: um estudo de caso na Universidade Estadual de Londrina

Pós-graduação em Design - FAAC

Aplicação de produtos de efeitos fisiológicos na pro- dução de brócolis tipo ramoso

Pós-graduação em Agronomia (Horticultura) - FCA

Serviço de valor adicionado para venda de produtos na TV universitária: proposta de um modelo de negócio complementar

Pós-graduação em Televisão Digital: Informação e Conhecimento - FAAC

Biomassa de Rubrivivax gelatinosus na criação de frangos de corte: desempenho animal e cor dos produtos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Extração de dados de produtos em páginas de comércio eletrônico

Pós-graduação em Ciência da Computação - IBILCE

Efeitos bioquímicos de contaminação em girinos de Eupemphix nattereri expostos a solos contendo o agrotóxico fipronil e seus produtos de degradação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da atividade de água em co-produtos da indústria de sucos: sementes de maracujá, casca de laranja e cascas de manga

Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE

Acúmulo de carboidratos no desenvolvimento de tomateiro tratado com produtos químicos

This work had the purpose to study the physiological effects of pyraclostrobin, boscalid, plant growth regulators and plant extract on the accumulation of carbohydrates during the development of tomato plants (Solanum lycopersicum L.), hybrid Giuliana, in protected environment conditions. The treatments were: T1- control; T2- pyraclostrobin 0.2 g L-1; T3- boscalid 0.075 g L-1, T4- pyraclostrobin 0.2 g L-1 + boscalid 0.075 g L-1, T5- IBA + GA(3) + kinetin 375 mg L-1, T6- GA(4+7) + benzylaminopurine 100 mg L-1 and T7- plant extract 100 mg L-1. The carbohydrate accumulation curve was accomplished with 5 samples, at 20-day intervals between evaluations, the 1st evaluation being carried out at 30 days after transplantation, on the day of the first treatment application. At each sampling the plants were separated in stem, leaves and fruits, of which the contents of total soluble sugars, reducing sugars and saccharose were evaluated. The effects of the treatments on chlorophyll content and gas exchanges were also evaluated. The experimental design was completely randomized, with 4 repetitions and 6 destructive evaluations during the development, with 1 plant per experimental unit for each sampling. The pyraclostrobin and boscalid applied in isolation and/or combined favor the increase of carbohydrates in leaves, stems and fruits of tomato hybrid Giuliana.

Modelo de referência para o processo de desenvolvimento de produtos de empresas eletrônicas de base tecnológica de médio porte

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Supressividade a Fusarium oxysporum f. sp. cubense por produtos orgânicos

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Distribuição espacial da deriva de produtos fitossanitários em pulverizações na cultura da laranja

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Otimização de método para analise de tebutiurom, diurom e seus produtos de degradação em água superficial

In 2001, it was estimated that pesticide used worldwide exceeded 2.27 billion kilograms, over 35%, of which, were herbicides. Brazil is considered one of the leaders in the production of sugarcane and mainly ethanol as fuel. The monoculture of sugarcane requires the usage of a range of pesticides, among these, the herbicides diuron and tebuthiuron. The degradation products most studied (DCA and DCPU) are diuron's, especially for toxicological characteristics of this herbicide that is identified as carcinogen and suspected to be endocrine disruptor in mammals. After optimization of the chromatographic separation using HPLC-UV, the analytical curve was constructed in solvent and subsequently in the matrix (surface water). The extraction method contains the usage of SPE (solid phase extraction) (Strata-X, 200 mg/6 mL), applicating 1L of sample and elution with 5 mL of acetonitrile / methanol (50:50, v/v). Analysis by HPLC/UV was performed in gradient mode, acetonitrile/water (70/30-74/26 by 1 min, 74/26 - 78/22 till 3.2 min, returning to initial conditions and remaining this way until 10 min), 018 column (Phenomenex, 4.6 mm diameter, 250 mm long and 5pm particle size) and detection at 254 nm. Tests F and t were performed to verify the presence of the matrix effect. There was matrix effect to all analytes, ranging from -33% (DCA) and 38% (tebuthiuron). Thereby the method was optimized and validated for analysis of diuron, tebuthiuron, and DCPU DCA in surface water using HPLC/UV. The data obtained show that in order to assure the analytical reliability desired the use of the analytical curves in the matrix for the quantification of these analytes in water is required.