The gluon propagator from large asymmetric lattices

The Landau-gauge gluon propagator is computed for the SU(3) gauge theory on lattices up to a size of $32^3 \times 200$. We use the standard Wilson action at $\beta = 6.0$ and compare our results with previous computations using large asymmetric and symmetric lattices. In particular, we focus on the impact of the lattice geometry and momentum cuts to achieve compatibility between data from symmetric and asymmetric lattices for a large range of momenta.Comment: Poster presented at Lattice2007, Regensburg, July 30 - August 4, 200

Chronic treatment with hydroxychloroquine and SARS-CoV-2 infection

Hydroxychloroquine sulfate (HCQ) is being scrutinized for repositioning in the treatment and prevention of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This antimalarial drug is also chronically used to treat patients with autoimmune diseases. By analyzing the Portuguese anonymized data on private and public based medical prescriptions we have identified all cases chronically receiving HCQ for the management of diseases, such as systemic lupus erythematosus, rheumatoid arthritis, and other autoimmune diseases. Additionally, we have detected all laboratory confirmed cases of SARS-CoV-2 infection and all laboratory confirmed negative cases in the Portuguese population (mandatorily registered in a centrally managed database). Cross linking the two sets of data has allowed us to compare the proportion of HCQ chronic treatment (at least 2 grams per month) in laboratory confirmed cases of SARS-CoV-2 infection with laboratory confirmed negative cases. Out of 26 815 SARS-CoV-2 positive patients, 77 (0.29%) were chronically treated with HCQ, while 1215 (0.36%) out of 333 489 negative patients were receiving it chronically (P = .04). After adjustment for age, sex, and chronic treatment with corticosteroids and/or immunosuppressants, the odds ratio of SARS-CoV-2 infection for chronic treatment with HCQ has been 0.51 (0.37-0.70). Our data suggest that chronic treatment with HCQ confer protection against SARS-CoV-2 infection.info:eu-repo/semantics/publishedVersio

Comparison of solar radio and EUV synoptic limb charts during the present solar maximum

The present solar cycle is particular in many aspects: it had a delayed rising phase, it is the weakest of the last 100 years, and it presents two peaks separated by more than one year. To understand the impact of these characteristics on the solar chromosphere and coronal dynamics, images from a wide wavelength range are needed. In this work we use the 17~GHz radio continuum, formed in the upper chromosphere and the EUV lines 304 and 171~{\AA}, that come from the transition region (He II) and the corona (Fe IX, X), respectively. We analyze daily images at 304 and 171~{\AA} obtained by the Atmospheric Imaging Assembly (AIA). The 17~GHz maps were obtained by the Nobeyama Radioheliograph (NoRH). To construct synoptic limb charts, we calculated the mean emission of delimited limb areas with 100" wide and angular separation of $5^\circ$. At the equatorial region, the results show an hemispheric asymmetry of the solar activity. The northern hemisphere dominance is coincident with the first sunspot number peak, whereas the second peak occurs concurrently with the increase in the activity at the south. The polar emission reflects the presence of coronal holes at both EUV wavelengths, moreover, the 17~GHz polar brightenings can be associated with the coronal holes. Until 2013, both EUV coronal holes and radio polar brightenings were more predominant at the south pole. Since then they have not been apparent in the north, but thus appear in the beginning of 2015 in the south as observed in the synoptic charts. This work strengthens the association between coronal holes and the 17~GHz polar brightenings as it is evident in the synoptic limb charts, in agreement with previous case study papers. The enhancement of the radio brightness in coronal holes is explained by the presence of bright patches closely associated with the presence of intense unipolar magnetic fields.Comment: 6 pages, 5 figures. Acccepted for publication in Astronomy & Astrophysic

New Sign Uncertainty Principles

We prove new sign uncertainty principles which vastly generalize the recent developments of Bourgain, Clozel & Kahane and Cohn & Gon\c{c}alves, and apply our results to a variety of spaces and operators. In particular, we establish new sign uncertainty principles for Fourier and Dini series, the Hilbert transform, the discrete Fourier and Hankel transforms, spherical harmonics, and Jacobi polynomials, among others. We present numerical evidence highlighting the relationship between the discrete and continuous sign uncertainty principles for the Fourier and Hankel transforms, which in turn are connected with the sphere packing problem via linear programming. Finally, we explore some connections between the sign uncertainty principle on the sphere and spherical designs.Comment: 45 pages, 2 figures, 3 tables, v3: typos corrected, numerics extende

Analysis of the ecological preferences of spontaneous vegetation. Case study applied to winter cereals

Se efectuaron 100 muestreos florísticos en parcelas de trigo, avena, cebada, caracterizándose algunas variables como el pH, textura del suelo, contenido en fósforo y potasio, precipitación, tipos de suelos y cultivos. Se realizó un análisis de frecuencias y abundancia de las especies. El método estadístico usado para las preferencias ecológicas fue el Método de los Perfiles Ecológicos e Información Mutua complementado con la aplicación del Método de Análisis Canónico de Correspondencias. Según el Método de Perfiles Ecológicos e Información Mutua, la distribución de la vegetación estudiada está estrechamente relacionada con la textura y pH. Los resultados de la aplicación del criterio de información Akaike y función ANOVA confirman los mismos factores como discriminantes en la distribución de la vegetación.It was Conducted 100 floristic surveys in fields of wheat, oat, barley together with the measurement of some variables, such as pH, soil texture, phosphorus and potassium content, precipitation, soil types and type of crops. An analysis of frequency and abundance of species was performed. The statistical method used for ecological preferences was the Ecological profiles and Mutual Information methodology complemented with the Canonical Correspondence Analysis methodology. According the Method of Ecological profiles and Mutual Information, the distribution of species is closely related to texture and pH. The application of Akaike information criterion and ANOVA function confirm the same factors as discriminating the distribution of vegetation

Study of autumn-winter weeds in Portugal and its ecological preferences

The conclusion of the dam project located in Alqueva, in Southern Portugal, has resulted in a significant increase of new irrigated areas, since 2006. This has meant that, in recent years, there have been progressive flora changes in farming systems traditionally implemented in the Alentejo region. The present work has analyzed the weed flora in an early stage of these changes, and the impact of environmental factors on the distribution of natural vegetation under Mediterranean climate conditions in the influence area of Alqueva. In 2007, 105 floristic surveys were carried out in autumn-winter crop plots or other soil use, and 264 species were identified. Families with higher expression were: Asteraceae, Poaceae, and Fabaceae. Only three species have been identified in more than half of farms, Avena sterilis, Phalaris minor and Lolium rigidum and they were part of the 15 species that revealed high and very high infestation degrees. Soil texture and extractable phosphorus have been determined as active ecological factors, according to the method of ecological profiles and Mutual Information. Therefore, these factores were those with the greatest influence on the species distribution. L. rigidum distribution showed to be associated with medium soil texture and A. sterilis distribution also showed to be associated with medium and fine soil texture soils, without showing ecological preference by extractable phosphorus. The distribution of P. minor was not related to the soil texture but showed preference for soils with medium phosphorus contentinfo:eu-repo/semantics/publishedVersio

Sowing season of corn with cowpea and corn intercropping in the weed control. I. Green ears yield.

Green ears yield losses caused by weeds may reach up to 52%. Reducing the use of herbicides is one of agriculture's major goals and several alternatives are currently being investigated, including intercropping. The goal of this work was to evaluate the effects of cowpea sowing season, intercropped with corn, on green ear yield of two corn cultivars. The experiment was carried out as random blocks with four replicates. Corn cultivars AG 1051 and AG 2060 were submitted to the following treatments: no hoeing, two hoeings (20 and 40 days after planting), and cowpea planting (cultivar BR 4, with indeterminate growth) at corn planting and at 5, 10, and 15 days later. Twenty-eight weed species were found in the experiment area. The highest marketable green ear yields were obtained with hoeing, while the lowest were obtained without hoeing. Intercropping with cowpea, especially when done early, provided intermediate results, indicating that the legume controlled weeds to a certain extent, which was, however, insufficient to avoid corn yield loss. The cultivars do not differ with regard to green ear yield. Cowpea yields were nearly null (data not shown)

Diferenciação genética entre procedências de açaizeiro por marcadores RAPD e SSR.

Diferenciação genética refere-se à distribuição da variabilidade entre e dentro de populações, procedências ou outros tipos de agrupamentos. Seu conhecimento é importante para estabelecer estratégias de coleta, conservação e manejo de germoplasma de qualquer espécie. Neste trabalho, avaliou-se a diferenciação genética entre procedências de açaizeiro que compõem a coleção da Embrapa Amazônia Oriental, por meio de marcadores RAPD e SSR. Para tanto, foram utilizados DNAs de 107 acessos, representantes de 17 regiões geográficas diferentes e utilizados em PCR com 28 primers RAPD e sete primers SSR. Os dados foram submetidos à análise de variância molecular (AMOVA) com estrutura hierárquica desbalanceada. Altos níveis de diferenciação genética foram registrados entre procedências, com 0,301 para o marcador dominante e 0,242 para o co-dominante. Para os dois marcadores, a AMOVA apresentou grande variabilidade dentro das procedências (acima de 69%). O pequeno tamanho amostral das procedências do Maranhão pode ter contribuído para a diferenciação significativa entre procedências. Os dados obtidos por esses marcadores foram concordantes quanto à distribuição da variação genética entre e dentro de procedências dessa palmeira

Acesso a inovação e reestruturação produtiva da agricultura familiar no tropico Semi-Arido: o caso das comunidades rurais de Massaroca (Juazeiro, BA).

Esse artigo trata da reestruturacao da agricultura familiar nas comunidades rurais de Massaroca (Juazeiro, BA) em decorrencia do acesso as inovacoes e aos recursos, resultantes da intervencao das instituicoes de pesquisa e de desenvolvimento. Analisa-se a difusao da informacao e da inovacao via as redes de relacoes apropriadas da inovacao e dos recursos, assim como as consequencias. Os resultados das operacoes de desenvolvimento local mostram os beneficios coletivos para as comunidades em termos de representatividade e de acesso aos equipamentos. Evidenciam, tambem, uma diferenciacao social entre os produtores, estimulada pela valorizacao diferenciada da informacao e do credito rural