Application Of Prediction Models Of Asian Soybean Rust In Two Crop Seasons, In Londrina, Pr

Predictive models of Asian soybean rust have been described by researchers to estimate favorable responses to epidemics. The prediction strategies are based on weather data obtained during period when initial symptoms of the disease are observed. Therefore, this study will evaluate the application of two prediction models of Asian soybean rust, and compare the results from two harvest seasons. The experiments were carried out during the 2011/2012 and 2012/2013 seasons in Londrina, PR. "SIGA spore traps" were installed to monitor the presence of Phakopsora pachyrhizi uredospores, and "Electronic trees," to collect data on weather variables. Following the detection of the first urediniospores, incidence and disease severity were assessed and compared with the predictions made by the models. The model described by Reis et al. (2004) did not indicate favorable conditions for the development of the first rust lesions following the detection of the first urediniospores during the 2011/2012 season. The premonitory symptoms of rust in the first and second harvest seasons were observed only when the model of Reis et al. (2004) indicated SDVPI close to 15 units. The model of Del Ponte et al. (2006b) overestimated the final rust severity during the two seasons.3752881288

Induction of a gloverin-like antimicrobial polypeptide in the sugarcane borer Diatraea saccharalis challenged by septic injury

Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) is an important pest for Brazilian sugarcane. In the present study, we detected two distinct spots in hemolymph from septic injured larvae (HDs1 and HDs2), which are separated by 2DE gel electrophoresis. Both spots were subjected to in-gel tryptic digestion and MALDI-TOF/TOF analysis, which revealed the sequence VFGTLGSDDSGLFGK present in both HDs1 and HDs2. This sequence had homology and 80% identity with specific Lepidoptera antimicrobial peptides called gloverins. Analyses using the ImageMaster 2D software showed pI 8.94 of the HDs1 spot, which is similar to that described to Hyalophora gloveri gloverin (pI 8.5). Moreover, the 14-kDa molecular mass of the spot HDs1 is compatible to that of gloverins isolated from the hemolymph of Trichoplusia ni, Helicoverpa armigera and H. gloveri. Antimicrobial assays with partially purified fractions containing the HDs1 and HDs2 polypeptides demonstrated activity against Escherichia coli. This is the first report of antimicrobial polypeptides in D. saccharalis, and the identification of these peptides may help in the generation of new strategies to control this pest

Short-range interactions in a two-electron system: energy levels and magnetic properties

The problem of two electrons in a square billiard interacting via a finite-range repulsive Yukawa potential and subjected to a constant magnetic field is considered. We compute the energy spectrum for both singlet and triplet states, and for all symmetry classes, as a function of the strength and range of the interaction and of the magnetic field. We show that the short-range nature of the potential suppresses the formation of ``Wigner molecule'' states for the ground state, even in the strong interaction limit. The magnetic susceptibility $\chi(B)$ shows low-temperature paramagnetic peaks due to exchange induced singlet-triplet oscillations. The position, number and intensity of these peaks depend on the range and strength of the interaction. The contribution of the interaction to the susceptibility displays paramagnetic and diamagnetic phases as a function of $T$.Comment: 12 pages,6 figures; to appear in Phys. Rev.

Model-based estimation of transmissibility and reinfection of SARS-CoV-2 P.1 variant

Acknowledgements We are grateful for the collaborative work of the reviewers and the entire group of the Observatório COVID-19 BR. In particular, we thank Verônica Coelho for critical inputs. We also thank the research funding agencies: the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brazil (Finance Code 001 to F.M.D.M., L.S.F. and T.P.P.), Conselho Nacional de Desenvolvimento Científico e Tecnológico—Brazil (grant number: 315854/2020-0 to M.E.B., 141698/2018-7 to R.L.P.S., 313055/2020-3 to P.I.P., 312559/2020-8 to M.A.S.M.V., 311832/2017-2 to R.A.K., 305703/2019-6 to A.A.M.S.) and Fundação de Amparo à Pesquisa do Estado de São Paulo—Brazil (grant number: 2019/26310-2 and 2017/26770-8 to C.F., 2018/26512-1 to O.C., 2018/24037-4 to S.P. and contract number: 2016/01343-7 to R.A.K.). The findings and conclusions in this article are those of the authors and do not necessarily represent the official position of the Centers of Disease Control and Prevention.Peer reviewe

Radiation-induced oscillatory magnetoresistance as a sensitive probe of the zero-field spin splitting in high mobility GaAs/AlGaAs devices

We suggest an approach for characterizing the zero-field spin splitting of high mobility two-dimensional electron systems, when beats are not readily observable in the Shubnikov-de Haas effect. The zero-field spin splitting and the effective magnetic field seen in the reference frame of the electron is evaluated from a quantitative study of beats observed in radiation-induced magnetoresistance oscillations.Comment: 4 pages, 4 color figure

Soil cover plants on water erosion control in the South of Minas Gerais

Water erosion is responsible for soil, water, carbon and nutrient losses, turning into the most important type of degradation of Brazilian soils. This study aimed to evaluate the influence of three cover plants under two tillage systems on water erosion control in an Argisol at south of Minas Gerais state, Brazil. The cover plants utilized in the study were pigeon pea, jack bean and millet, under contour seeding and downslope tillage. Experimental plots of 4 x 12 m, with 9% slope, under natural rainfall were used for the quantification of losses of soil, water, nutrients, and organic matter. One experimental plot was kept without plant cover (reference). Higher erosivity was observed in December and January, although a great quantity of erosive rainfall was detected during the whole raining period. Contour seeding provided a greater reduction of water erosion than downslope tillage, as expected. The jack bean under contour seeding revealed the lowest values of soil, water, nutrients and organic matter losses

Orange Pectin Mediated Growth and Stability of Aqueous Gold and Silver Nanocolloids

International audienceThe role of orange based pectin in the nucleation and growth of silver and gold nanoparticles is addressed. Pectin is a complex polysaccharide found in fruits such as oranges, lemons, passion fruits or apples. It displays smooth and hairy chain regions contg. hydroxyl-​, ester-​, carboxylate- and eventually amine groups that can act as surface ligands interacting under various pH conditions more or less efficiently with growing nanometals. Here, a high methoxy pectin (>50​% esterified) was used as a stabilizer​/reducing agent in the prepn. of gold, silver and silver-​gold nanoparticles. Com. pectin (CP) and pectin extd. from orange bagasse (OP) were used. Optionally, trisodium citrate or oxalic acid we used to reduce AgNO3 and HAuCl4 in aq. environment. Characterization methods included UV-​vis absorption spectroscopy, transmission electron microscopy, electron diffraction and energy-​dispersive X-​ray spectroscopy. The results show that under different pH conditions, pectin and reducing agents allow producing various nanostructures shapes (triangles, spheres, rods, octahedrons and decahedrons) often with high polydispersity and sizes ranging between 5 nm and 30 nm. In addn., depending on Ag​/Au-​ratio and pH, the surface plasmon bands can be continuously shifted between 410 nm and 600 nm. Finally, pectin seems to be a highly efficient stabilizer of the colloidal systems that show a remarkable stability and unchanged optical spectral response even after five years

The impact of roughness elements on sediment fluxes in coastal dunes and dune valleys: solving the puzzle for Spanjaards Duin

In 2009 a new dune area called Spanjaards Duin was constructed in front of the Delfland Coast. Spanjaards Duin was created as a compensation measure for the expected increase in nitrogen deposition from the expansion of the Rotterdam harbour (Maasvlakte 2). The predefined compensation goal is to reach 6 ha of moist dune slack vegetation and 10 ha of dry grey dune in 2033. This is pursued by creating favourable abiotic conditions for natural vegetation establishment (van der Meulen et al., 2014). Sediment fluxes affect establishment and growth of vegetation and shape the dune landscape. Therefore, there is need to know how sediment fluxes behave in Spanjaards Duin

Compilation of parameterized seismogenic sources in Iberia for the SHARE European-scale seismic source model.

Abstract: SHARE (Seismic Hazard Harmonization in Europe) is an EC-funded project (FP7) that aims to evaluate European seismic hazards using an integrated, standardized approach. In the context of SHARE, we are compiling a fully-parameterized active fault database for Iberia and the nearby offshore region. The principal goal of this initiative is for fault sources in the Iberian region to be represented in SHARE and incorporated into the source model that will be used to produce seismic hazard maps at the European scale. The SHARE project relies heavily on input from many regional experts throughout the Euro-Mediterranean region. At the SHARE regional meeting for Iberia, the 2010 Working Group on Iberian Seismogenic Sources (WGISS) was established; these researchers are contributing to this large effort by providing their data to the Iberian regional integrators in a standardized format. The development of the SHARE Iberian active fault database is occurring in parallel with IBERFAULT, another ongoing effort to compile a database of active faults in the Iberian region. The SHARE Iberian active fault database synthesizes a wide range of geological and geophysical observations on active seismogenic sources, and incorporates existing compilations (e.g., Cabral, 1995; Silva et al., 2008), original data contributed directly from researchers, data compiled from the literature, parameters estimated using empirical and analytical relationships, and, where necessary, parameters derived using expert judgment. The Iberian seismogenic source model derived for SHARE will be the first regional-scale source model for Iberia that includes fault data and follows an internationally standardized approach (Basili et al., 2008; 2009). This model can be used in both seismic hazard and risk analyses and will be appropriate for use in Iberian- and European-scale assessments

Determinants of the current and future distribution of the West Nile virus mosquito vector Culex pipiens in Spain

Changes in environmental conditions, whether related or not to human activities, are continuously modifying the geographic distribution of vectors, which in turn affects the dynamics and distribution of vector-borne infectious diseases. Determining the main ecological drivers of vector distribution and how predicted changes in these drivers may alter their future distributions is therefore of major importance. However, the drivers of vector populations are largely specific to each vector species and region. Here, we identify the most important human-activity-related and bioclimatic predictors affecting the current distribution and habitat suitability of the mosquito Culex pipiens and potential future changes in its distribution in Spain. We determined the niche of occurrence (NOO) of the species, which considers only those areas lying within the range of suitable environmental conditions using presence data. Although almost ubiquitous, the distribution of Cx. pipiens is mostly explained by elevation and the degree of urbanization but also, to a lesser extent, by mean temperatures during the wettest season and temperature seasonality. The combination of these predictors highlights the existence of a heterogeneous pattern of habitat suitability, with most suitable areas located in the southern and northeastern coastal areas of Spain, and unsuitable areas located at higher altitude and in colder regions. Future climatic predictions indicate a net decrease in distribution of up to 29.55%, probably due to warming and greater temperature oscillations. Despite these predicted changes in vector distribution, their effects on the incidence of infectious diseases are, however, difficult to forecast since different processes such as local adaptation to temperature, vector-pathogen interactions, and human-derived changes in landscape may play important roles in shaping the future dynamics of pathogen transmission.info:eu-repo/semantics/acceptedVersio