Evaluation of low-frequency voltage dividers, using the step response

PostprintA method to characterize the behavior of low frequency voltage dividers, based on the step response, is presented. Amplitude errors and phase displacements can be evaluated, in an absolute way, without any auxiliary standard divider

Future climate change in the Agulhas system and its associated impact on South African rainfall

South African climate variability has been linked to changes in both the Agulhas system and external forcing (i.e. CO2 and ozone). We analysed future climate change in the Agulhas system volume transport and its associated impacts on South Africa’s precipitation using the Community Climate System Model version 4 as part of the Coupled Model Intercomparison Project, phase 5. Output from one historical and three future greenhouse gas emission scenarios were examined to project various climate storylines. We found that the Agulhas Current volume transport decreases across all three scenarios and that the current displays a strong baroclinic component with an increase in transport at the surface and decrease at intermediate depths. Agulhas leakage was found to increase with historical emissions. Additionally, an east-west dipole pattern for convective precipitation was found over South Africa, with an increase over the eastern region related to an increase in greenhouse gas emissions and a decrease in the western region linked to the location of Hadley cell edge latitude. Moving into the 21st century, future predictions in regional climate variability are shown to be dependent on the intensity of greenhouse gas emissions and are extremely important for South Africa, a region prone to drought and flooding and home to a large population dependent on rain-fed agriculture. Significance: • Future climate variability in the Agulhas system and South African region is heavily dependent on changes in external forcing. • The Agulhas Current volume transport decreases as the greenhouse gas emissions continue to increase and a strong baroclinic component is found with an increase in transport at the surface and a decrease at the intermediate depths. • A strong east-west dipole precipitation pattern is found over South Africa with the increase in the eastern region related to the increase in greenhouse gas emissions and the decrease in the western region related to the location of the Hadley cell edge latitude

Effects of curcumin in an orthotopic murine bladder tumor model

Cigarette smoking (CS) is the main risk factor for bladder cancer development. There are more than 100 carcinogens present in cigarette smoke. Among the potential mediators of CS-induced alterations is nuclear factor-kappa (NF-κB), which is responsible for the transcription of genes related to cell transformation, tumor promotion, angiogenesis, invasion and metastasis. Curcumin is a polyphenol compound derived from Curcuma longa that suppress cellular transformation, proliferation, invasion, angiogenesis, and metastasis by down regulating NF-κB and its regulated genes. The aim of our study was to assess the effects of curcumin in bladder urothelial carcinoma. We studied the effects of curcumin in vitro and in vivo using the orthotropic syngeneic bladder tumor animal model MB49. Curcumin promotes apoptosis of bladder tumor cells in vitro. In vivo tumors of animals treated with curcumin were significantly smaller as compared to controls. Using immunohistochemistry, we demonstrated a decrease in the expression of Cox-2 by 8% and Cyclin D1 by 13% in the animals treated with curcumin; both genes regulated by NF-κB and related to cell proliferation. In this study, we showed that curcumin acts in bladder urothelial cancer, possibly dowregulating NF-κB-related genes, and could be an option in the treatment of urothelial neoplasms. The results of our study suggest that further research is warranted to confirm our findings

Biplot analysis of strawberry genotypes recommended for the State of Espírito Santo.

Most strawberry genotypes grown commercially in Brazil originate from breeding programs in the United States, and are therefore not adapted to the various soil and climatic conditions found in Brazil. Thus, quantifying the magnitude of genotype x environment (GE) interactions serves as a primary means for increasing average Brazilian strawberry yields, and helps provide specific recommendations for farmers on which genotypes meet high yield and phenotypic stability thresholds. The aim of this study was to use AMMI (additive main effects and multiplicative interaction) and GGE biplot (genotype main effects + genotype x environment interaction) analyses to identify high-yield, stable strawberry genotypes grown at three locations in Espírito Santo for two agricultural years. We evaluated seven strawberry genotypes (Dover, Camino Real, Ventana, Camarosa, Seascape, Diamante, and Aromas) at three locations (Domingos Martins, Iúna, and Muniz Freire) in agricultural years 2006 and 2007, totaling six study environments. Joint analysis of variance was calculated using yield data (t/ha), and AMMI and GGE biplot analysis was conducted following the detection of a significant genotypes x agricultural years x locations (G x A x L) interaction. During the two agricultural years, evaluated locations were allocated to different regions on biplot graphics using both methods, indicating distinctions among them. Based on the results obtained from the two methods used in this study to investigate the G x A x L interaction, we recommend growing the Camarosa genotype for production at the three locations assessed due to the high frequency of favorable alleles, which were expressed in all localities evaluated regardless of the agricultural year

Repeatability and minimum number of evaluations for morpho-agronomic characters of elephant-grass for energy purposes.

ABSTRACT Due to the need to promote information relevant to elephant-grass breeding programs for energy purposes, this work aimed to estimate the coefficient of repeatability of the main morpho-agronomic characters and to predict the minimum number of cuts required for selection with greater efficiency. A total of 73 elephant-grass genotypes were evaluated in a randomized block design, in a subdivided plot scheme with two replicates. Nine cuts were performed at six-month intervals, from June 2012 to December 2016, in the municipality of Campos dos Goytacazes, RJ. We estimated the repeatability coefficients for dry matter yield (DMY), number of tillers (NT), plant height (PH), stem diameter (SD) and leaf blade width (LBW), using the methods of analysis of variance, principal components and structural analysis. At least nine, three, six, six and three cuts should be performed, considering the DMY, NT, PH, SD and LBW characteristics, respectively, to predict the true value of the genotypes with 80% reliability