Abstract The signal digitization process of the open television system is still in progress, therefore, the study of the digital signal propagation has great importance so that broadcasters can develop and improve the transmission service. The field measurement of digital signal parameters is one of the most reliable means to analyze the signal propagation in a given area. In this work, received power measurements of a TV station digital signal in the city of Mossoró, Rio Grande do Norte, Brazil were performed. The objective is to implement interpolation methods and identify which is the most suitable for the spatial representation of power data in this region through the Mean Error (ME) and Root Mean Squared Error (RMSE) evaluation metrics. A good representation of the received power level contributes to the mapping of greater and lesser intensity of the digital signal in the region. The implementation of the interpolation methods was performed in Surfer® software (Golden Software, LLC), which provides the cross-validation report with the ME and RMSE values associated with each method. The Ordinary Kriging method with exponential variogram model obtained the lowest RMSE value (7.6083) and, therefore, the most adequate estimates.

Spirulina platensis é uma microalga rica em proteínas que apresenta composição apropriada para utilização como complemento alimentar.. O objetivo deste trabalho foi avaliar diferentes concentrações de Spirulina platensis como revestimento biodegradável na conservação pós-colheita de goiaba ‘Paluma’ sob armazenamento refrigerado e ambiente. O ensaio foi desenvolvido na Universidade Federal de Campina Grande, Centro de Ciências e Tecnologia Agroalimentar e instalado em delineamento inteiramente casualizado, em esquema fatorial 2 x 4 x 5, utilizando dois tipos armazenamento (a 10 ± 2°C, com 85±5%UR e a 24 ± 2°C, com 85±5% UR), quatro concentrações da microalga (0%, 1%, 2% e 3%) e cinco períodos de avaliação (0, 3, 6, 9 e 12 dias). Os resultados mostraram que os revestimentos com Spirulina platensis foram eficientes no retardo da perda de massa nos frutos em ambas as temperaturas de armazenamento, sendo o tratamento T2, que se refere a concentração de 1% a 10±2°C o mais eficiente, proporcionando as menores perdas quando comparado a testemunha. Quanto às demais características de qualidade do fruto não foram observadas influências significativas dos revestimentos.

Spirulina platensis is a microalgae rich in proteins that has a composition suitable for use as a food supplement. The objective of this study was to evaluate different concentrations of Spirulina platensis as a biodegradable coating on post-harvest conservation of 'Paluma' guava under refrigerated storage and environment. The experiment was carried out at the Federal University of Campina Grande, Agro-Food Science and Technology Center and installed in a completely randomized design, in a 2 x 4 x 5 factorial scheme, using two types of storage (at 10 ± 2 ° C, 85 ± 5% (0, 1, 2 and 3%) and five evaluation periods (0, 3, 6, 9 and 12 days) ). The results showed that the coatings with Spirulina platensis were efficient in delaying the loss of mass in fruits at both storage temperatures, with the T2 treatment, which refers to a concentration of 1% at 10 ± 2 ° C, more efficient, providing the lowest losses when compared to the control. Regarding the other quality characteristics of the fruit, no significant influences of the coatings were observed.

O presente trabalho reporta a caracterização espectroscópica por absorção UV-visível, dicroísmo circular magnético (MCD) e ressonância paramagnética eletrônica (EPR) da proteína recombinante do tipoP450-canfora (P450CAM) codificada pela orf10 de Streptomyces clavuligerus (P450CLA) expressa por Escherichia coli Rosetta na forma nativa e associada a ligantes externos contendo os grupos β-lactamato, oxazol e derivado de alquilamina (álcool) do ácido clavulâmico. Considerando a diversidade de aplicações da enzima P450, sua reatividade com terc-butil-hidroperóxido (terc-BuOOH) foi caracterizada. O grupo heme da P450CLA apresenta-se covalentemente ligado e exibe características espectrais de UV-visível, CD e MCD de P450CAM, incluindo a banda Soret em 450 nm proveniente do complexo ferroso-CO. P450CLA foi convertido em espécies de valência alta pelo terc-BuOOH e promoveu cisão homolítica da ligação O-O. O perfil radicalar da reação foi terc-butiloxil como radical primário e metil e butilperoxil como radicais secundários. Os radicais metil e butilperoxil resultaram respectivamente da cisão-β do radical alcoxil e da reação do radical metil com oxigênio molecular.

The present study reports the spectroscopic characterization by UV-visible absorption spectroscopy, magnetic circular dichroism (MCD) and electron paramagnetic resonance (EPR) of the recombinant orf10-encoded P450-camphor like protein (P450CLA)of Streptomyces clavuligerus expressed in Escherichia coli Rosetta in the native form and associated to external ligands containing the β-lactam, oxazole and alkylamine-derived (alcohol) moieties of the clavulamic acid. Considering the diversity of potential applications for the enzyme, the reactivity with tert-butylhydroperoxide (tert-BuOOH) was also characterized. P450CLA presents a covalently bound heme group and exhibited the UV-visible, CD and MCD spectral features of P450CAM including the fingerprint Soret band at 450 nm generated by the ferrous CO-complex. P450CLA was converted to high valence species by tert-BuOOH and promoted homolytic scission of the O-O bond. The radical profile of the reaction was tert-butyloxyl as primary and methyl and butylperoxyl as secondary radicals. The secondary methyl and butylperoxyl radicals resulted respectively from the β-scission of the alkoxyl radical and from the reaction of methyl radical with molecular oxygen.

As alterações nas condições químicas do solo em virtude de diferentes sistemas de manejo com cana-de-açúcar podem causar modificações na dispersão de argila e no estado de agregação do solo. Estudaram-se os efeitos de diferentes sistemas de manejo com cana-de-açúcar nas propriedades físicas e químicas de um Argissolo Amarelo Coeso, selecionando-se quatro sistemas de uso e manejo, constituídos de uma área não irrigada, uma área irrigada, uma com aplicação de vinhaça e uma sob floresta nativa como condição original. Foram retiradas amostras de cada área a 0-0,2, 0,2-0,4 e 0,4-0,8 m de profundidade, para determinação das alterações nas propriedades físicas e químicas do solo. Os sistemas de manejo com cana-de-açúcar afetaram as propriedades químicas do solo, ocorrendo redução da capacidade de troca de cátions e aumento da condutividade elétrica, pH em água e concentração crítica de floculação. Essas alterações químicas resultaram numa dispersão maior de argila nos solos cultivados com cana-de-açúcar, reduzindo a estabilidade dos agregados em água.

Alterations in the chemical conditions of the soil due to different soil management systems with sugarcane can cause modifications in clay dispersion and in the state of aggregation of the soil. The effects of different soil management systems with sugarcane on the physical and chemical properties of a cohesive Yellow Argisol were studied, being selected four different use and management systems, constituted of a site with irrigated cultivation, a site with not irrigated cultivation, a site with vinasse application and a site under native forest as original condition. Samples of each site were collected at 0-0,2, 0,2-0,4 and 0,4-0,8 m depths to determine the alterations in the chemical and physical properties of soil. The management systems with sugarcane affected the chemical properties of the soil, resulting in reduction of cation exchange capacity and increase of the electrical conductivity, pH in water and critical flocculation concentration. These chemical alterations resulted in larger clay dispersion in the soil cultivated with sugarcane, reducing the stability of the aggregates in water.

A new Brazilian Calomys Waterhouse, 1837 species is described based on morphologic and karyologic data. This species is endemic to the Cerrado of Central Brazil and allopatric with all other species of the genus Calomys. Its chromosome complement (2n = 46, AN = 66) is different from those described in other Calomys species. Morphometric analysis significantly distinguished this new species from other Calomys of the Brazilian fauna like C. callosus (Renger, 1830), C. expulsus (Lund, 1841) and C. tener (Winge, 1887) and placed it among the large-sized Calomys.