Thin film deposition with time varying temperature

We study the effects of time-dependent substrate/film temperature in the deposition of a mesoscopically thick film using a statistical model that accounts for diffusion of adatoms without lateral neighbors whose coefficients depend on an activation energy and temperature. Dynamic scaling with fixed temperature is extended to predict conditions in which the temperature variation significantly affects surface roughness scaling. It agrees with computer simulation results for deposition of up to ${10}^4$ atomic layers and maximal temperature changes of $30 K$, near or below the room temperature. If the temperature decreases during the growth, the global roughness may have a rapid growth, with effective exponents larger than 1/2 due to the time-decreasing adatom mobility. The local roughness in small box size shows typical evidence of anomalous scaling, with anomaly exponents depending on the particular form of temperature decrease. If the temperature increases during the growth, a non-monotonic evolution of the global roughness may be observed, which is explained by the competition of kinetic roughening and the smoothing effect of increasing diffusion lengths. The extension of the theoretical approach to film deposition with other activation energy barriers shows that similar conditions on temperature variation may lead to the same morphological features. Equivalent results may also be observed by controlling the deposition flux.Comment: 18 pages, 8 figure

The low affinity glucose transporter HxtB is also involved in glucose signalling and metabolism in Aspergillus nidulans

One of the drawbacks during second-generation biofuel production from plant lignocellulosic biomass is the accumulation of glucose, the preferred carbon source of microorganisms, which causes the repression of hydrolytic enzyme secretion by industrially relevant filamentous fungi. Glucose sensing, subsequent transport and cellular signalling pathways have been barely elucidated in these organisms. This study therefore characterized the transcriptional response of the filamentous fungus Aspergillus nidulans to the presence of high and low glucose concentrations under continuous chemostat cultivation with the aim to identify novel factors involved in glucose sensing and signalling. Several transcription factor- and transporter-encoding genes were identified as being differentially regulated, including the previously characterized glucose and xylose transporter HxtB. HxtB was confirmed to be a low affinity glucose transporter, localizing to the plasma membrane under low- and high-glucose conditions. Furthermore, HxtB was shown to be involved in conidiation-related processes and may play a role in downstream glucose signalling. A gene predicted to encode the protein kinase PskA was also identified as being important for glucose metabolism. This study identified several proteins with predicted roles in glucose metabolic processes and provides a foundation for further investigation into the response of biotechnologically important filamentous fungi to glucose

BRS Araguaia: cultivar híbrida de melão amarelo.

?BRS Araguaia? é uma cultivar híbrida de melão (Cucumis melo L.) do grupo varietal amarelo desenvolvida no âmbito do programa de melhoramento genético de melão da Embrapa e em parceria com a Emater-GO. As plantas são grandes, com crescimento vigoroso e excelente cobertura foliar. Os frutos são de formato elíptico, de razão comprimento/diâmetro em torno de 1,25, com casca de coloração amarela intensa e rugosidade média. A polpa é branca esverdeada clara e de textura firmelisa. Apresenta concentração de sólidos solúveis totais no ponto de colheita em torno de 13% e acidez em torno de 0,15%. Apresenta potencial produtivo de 40 t.ha-1 quando cultivada no Vale do Rio São Francisco-PE e BA, com concentração de frutos nas classes 6 e 7. O ciclo de maturação é em torno de 70 dias nas regiões Nordeste e Centro Oeste, em locais e/ou períodos do ano em que a média das temperaturas mínimas é superior a 25°C. ?BRS Araguaia? é resistente à raça 2 do oídio (Podosphaera xanthii), uma das principais doenças da cultura.(Suplemento CD-ROM: ABH, edição especial, 51º Congresso Brasileiro de Olericultura, Viçosa-MG)

Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, \nobreak{$6\times 10^{19}$eV}. The anisotropy was measured by the fraction of arrival directions that are less than $3.1^\circ$ from the position of an active galactic nucleus within 75 Mpc (using the V\'eron-Cetty and V\'eron $12^{\rm th}$ catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is $(38^{+7}_{-6})$, compared with $21$ expected for isotropic cosmic rays. This is down from the early estimate of $(69^{+11}_{-13})$. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.Comment: Accepted for publication in Astroparticle Physics on 31 August 201

How many species change names in a germplasm bank? Study of the Anhembi Experimental Station eucalypt germplasm bank and practical implications.

Eucalypts are a long-cycle crop that have been introduced in Brazil during several decades. The germplasm banks of the country make available several populations whose botanical classifications are somewhat outdated since these classifications have been subject to several modifications over the years. This study outlines a review of species with outdated classifications in the Anhembi Experimental Station of Forest Sciences (ESALQ/USP), one of Brazil?s main eucalypt germplasm banks and discusses the possible implications for the breeding programs that use said germplasm. In this survey, we found records that indicate introductions were made of populations of 20 eucalypts species. However, this number has increased according to the most recent update of botanical classifications, and the Anhembi Germplasm Bank has currently 22 species after a few species were reclassified. Furthermore, a major change has been the reclassification of some species from the genus Eucalyptus to the genus Corymbia. One original introduction, Eucalyptus maculata, is now considered to be (according to original provenances), Corymbia maculata and C. variegata. One species originally introduced as E. pellita has been renamed E. scias; E. pellita still exists in north Queensland, Australia and Papua New Guinea, while E. scias has a much smaller southerly distribution in New South Wales, Australia. Similarly, an introduction of E. phaeotricha is now generally considered to be E. tindaliae, and an introduction of E. resinifera is now considered to be E. macta (according to the provenance area of the introduction). The confusing classification of the species is aggravated, in some cases, by the lack of detailed studies that allow comparing the species introduced with the same name, regarding wood productivity, tolerance and/or traits that are fundamental for defining the species to be introduced or worked on by the breeding programs

The Fluorescence Detector of the Pierre Auger Observatory

The Pierre Auger Observatory is a hybrid detector for ultra-high energy cosmic rays. It combines a surface array to measure secondary particles at ground level together with a fluorescence detector to measure the development of air showers in the atmosphere above the array. The fluorescence detector comprises 24 large telescopes specialized for measuring the nitrogen fluorescence caused by charged particles of cosmic ray air showers. In this paper we describe the components of the fluorescence detector including its optical system, the design of the camera, the electronics, and the systems for relative and absolute calibration. We also discuss the operation and the monitoring of the detector. Finally, we evaluate the detector performance and precision of shower reconstructions.Comment: 53 pages. Submitted to Nuclear Instruments and Methods in Physics Research Section

Diversidade genética entre acessos de Arachis pintoi para comprimento e largura da estípula.

Poucos são os estudos de caracterização morfológica e diversidade genética que contemplam o comprimento e a largura das estípulas de Arachis pintoi. Este estudo teve como objetivos verificar a existência de variabilidade e conhecer a diversidade genética entre acessos de A. pintoi para as características comprimento e largura da estípula

Search for First Harmonic Modulation in the Right Ascension Distribution of Cosmic Rays Detected at the Pierre Auger Observatory

We present the results of searches for dipolar-type anisotropies in different energy ranges above $2.5\times 10^{17}$ eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% $C.L.$ for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.Comment: 28 pages, 11 figure