19 research outputs found
Avaliação da incidência de antracnose, do desempenho e estado nutricional de variedades de mangueira, para cultivo orgânico, na região centro-norte do Estado de São Paulo.
A mudança do perfil do consumidor, aliada aos riscos da contaminação por agrotóxicos, tem levado à busca de alternativas ecologicamente apropriadas para produção de frutas. Os objetivos deste trabalho foram avaliar a incidência de antracnose, o desempenho e estado nutricional de variedades de mangueira conduzidas organicamente na região de Pindorama-SP. Foram utilizadas 17 variedades de mangueira. O experimento foi instalado em delineamento experimental em blocos completos ao acaso, com 17 tratamentos (variedades) e seis repetições. Foi avaliada a severidade de antracnose nas folhas, através de uma escala diagramática, atribuindo-se notas aos sintomas. Foram avaliados o crescimento e o desenvolvimento (altura da planta, perímetro do tronco e da copa) e o estado nutricional, mediante análise foliar, das diferentes variedades utilizadas. Através dos resultados obtidos, podem-se considerar como muito suscetíveis à antracnose as variedades Bourbon, Rocha e Rosa; e resistentes, as variedades IAC 111, Alfa, Beta e Parvin; as variedades de manga apresentaram o mesmo padrão de crescimento; as maiores alturas da planta corresponderam aos maiores diâmetros do tronco e da copa; a variedade Parvin apresentou o melhor desempenho dentre as variedades estudadas, com relação à resistência à antracnose, altura e diâmetro do caule e da copa, podendo ser recomendada ao cultivo orgânico. As variedades Omega e Alfa também apresentaram bom crescimento, podendo ser indicadas para esse cultivo, pelo menos nessa fase inicial; as variedades Surpresa e Rosa não apresentaram bom desempenho, no campo, em relação às demais, não devendo ser recomendadas para o cultivo orgânico, principalmente a variedade Rosa, bastante suscetível à antracnose. As concentrações de N, P e K foram elevadas na fase vegetativa das plantas, comparadas à baixa concentração de Ca; houve carência de Boro em todas as variedades estudadas. A manga Rosa, provavelmente, sofreu toxicidade ao excesso de manganês, ocasionando diminuição em seu desenvolvimento
Endodontic Retreatment: Clinical Comparison Of Reciprocating Systems Versus Rotary System In Disinfecting Root Canals
Methods: Thirty endodontically treated teeth with post-treatment apical periodontitis were selected. The specimens were divided into three groups according to the system used: WaveOne (n = 10), Reciproc instrument (n = 10), and ProTaper Universal Retreatment system (n = 10). Samples were collected before and after chemomechanical preparation. The irrigation was performed by using 2.5 % sodium hypochlorite. A chromogenic limulus amebocyte lysate assay test was used to quantify endotoxins. Culture techniques were used to determine bacterial colony-forming unit counts.Introduction: This clinical study was conducted to compare the effectiveness of single-file reciprocating systems and rotary systems in removing endotoxins and cultivable bacteria in endodontic retreatment.Results: At baseline, endotoxins and cultivable bacteria were recovered from 100 % of the root canal samples in a median value of 5.84 EU/mL and 4.98 × 103 CFU/mL, respectively. After CMP, no differences were found in the median percentage values of endotoxin reduction achieved with reciprocating systems—WaveOne [94.11 %] and Reciproc [93.29 %] and with rotary systems—ProTaper [94.98 %] (P > 0.05). Both single-file reciprocating systems [WaveOne (98.27 %) and Reciproc (99.54 %)] and rotary system [ProTaper (98.73 %)] were effective in reducing bacterial load (P > 0.05). Moreover, no differences were found among the systems tested.Conclusions: The Reciproc and WaveOne reciprocating systems were as effective as the ProTaper system for removal of endotoxins and bacteria in endodontic retreatment.Clinical relevance: All systems tested were effective to remove cultivable bacteria and endotoxin in endodontic retreatment. As no differences among systems were observed, it is possible to suggest that clinicians should choose the preferred technique to perform endodontic
CO Adsorption on Modified Mg–Al-Layered Double Hydroxides
Because of increases in the burning of fossil fuels, there is an increased emission of pollutant gases (e.g. CO 2 ) into the atmosphere. An alternative to minimize these emissions is to capture these gases using porous materials, such as layered double hydroxides (LDHs). In this study, LDHs were synthesized by co-precipitation of ion salts of Mg 2+ and Al 3+ . After the synthesis, the materials were treated with a template to expand the layers. The samples were then characterized by X-ray diffraction, thermogravimetric analysis/derivative thermogravimetry, adsorption/desorption of nitrogen, scanning electron microscopy/energy-dispersive X-ray spectroscopy and transmission electron microscopy. A CO 2 adsorption study was then performed to determine the adsorption capacity of the material in accordance with the contact time between the gas and the adsorbent. The adsorption capacities of LDHs and LDHs-P123 for CO 2 were 0.72 and 1.36 mmol/g, respectively, showing satisfactory results post-treatment