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In this paper we survey the estimation of nonparametric regression models using wavelets, under different conditions on the innovations, on the predictor variables, on the function spaces involved and on the regularity conditions imposed. We begin with the seminal works of Donoho and co-authors, in the regular fixed design and independent and identically Gaussian noise and move towards non-regular designs, random designs and correlated errors.

We consider the situation of a univariate nonparametric regression where either the Gaussian error or the predictor follows a stationary strong mixing stochastic process and the other term follows an independent and identically distributed sequence. Also, we estimate the regression function by expanding it in a wavelet basis and applying a hard threshold to the coefficients. Since the observations of the predictor are unequally distant from each other, we work with wavelets warped by the density of the predictor variable. This choice enables us to retain some theoretical and computational properties of wavelets. We propose a unique estimator and show that some of its properties are the same for both model specifications. Specifically, in both cases the coefficients are unbiased and their variances decay at the same rate. Also the risk of the estimator, measured by the mean integrated square error is almost minimax and its maxiset remains unaltered. Simulations and an application illustrate the similarities and differences of the proposed estimator in both situations.

The combination of plant density, fungicide, and levels of genotype resistance to white mold (WM) has not been studied for its effect on performance of common bean with type III growth habit under WM pressure. We established four sprinkler-irrigated trials in the fall to winter season in Brazil, combining density (8, 14, 20, or 26 plants/m2), genotype (susceptible or partially resistant to WM), and fungicide to manage WM (two fluazinam applications or without fluazinam) at 0.5 m row spacing in fields infested with sclerotia. One trial was established in a warm region, aiming to obtain low WM pressure. For three trials, the linear mixed model was used. WM pressure in the trials ranged from low to high. Genotype × density × fungicide and genotype × density interactions were not significant for incidence, severity, and yield for all trials. In the three trials, severity was 29% lower at eight than at 26 plants/m2, and yield at 14 plants/m2 (3,294 kg/ha) was 14% higher than yield at eight plants/m2 (P = 0.035) where fluazinam was applied. However, without fluazinam, density did not affect yield. In conclusion, choices of plant density for type III bean cultivars do not need to take into account their resistance levels to WM in the fall to winter season. However, fungicide treatment to manage WM affects the choice of density, with 8 to 12 plants/m2 recommended if fungicide is not an option to manage WM (as in organic systems), and 10 to 14 plants/m2 recommended if fungicide applications are likely.

Fine aggregate matrix (FAM) has been regarded as a key constituent of asphalt mixtures. Although several design methods have been recently proposed to prepare FAM specimens that represent the materials contained within the asphalt concretes, the volumetric characteristics of FAM may not be uniformly distributed within samples compacted using devices such as the Superpave gyratory compactor (SGC). This can mislead the mechanical analyses conducted with testing specimens that are typically extracted from different locations of the compacted samples, as they can present varying volumetric characteristics. This study employs the advanced micro-computed tomography (CT) scan technique to evaluate the air void distribution within FAM specimens extracted from different locations of SGC samples compacted with distinct air void contents. Rheological tests are performed in a dynamic shear rheometer to determine the dynamic shear modulus of the testing specimens. A statistical analysis is conducted to evaluate potential correlations between the volumetric and the rheological characteristics of the FAMs and to identify locations within the SGC samples from which small cylindrical specimens with similar characteristics can be extracted and used for testing. The adoption of advanced techniques such as the CT scan is essential for the advancement of the knowledge on the complex characteristics of asphalt mixtures, and may facilitate the fabrication of FAMs that are more representative of those that comprise asphalt concretes, as well as allow the use of similar replicates in mechanical tests.

Online Learning Communities (OLC) are nowadays one of the most important producers of Big Data in education. However, the investigation of such environments is underrepresented in educational research. There is a lack of methods and tools that characterize the massive learning associated with the student participation in large OLC. This paper presents a Social Learning Analytics Dashboard (SLAD) to analyze temporal trend models that outline the evolution of learners behavior over time. Such models suggest that ongoing collaboration and positive emotion have a fundamental role for knowledge creation and sharing in large scale social learning. These findings can be used to take actions in order to enhance and regulate social interaction within large OLC.

RESUMO A cultivar de feijão vagem UENF Goytacá, registrada no Ministério da Agricultura, Pecuário e Abastecimento, foi obtida após a geração F6 pelo método de melhoramento Single Seed Descent (SSD). Pertence ao Programa de Melhoramento de feijão vagem da UENF que consiste de mais de uma década de pesquisa com a cultura, objetivando a recomendação de cultivares para as regiões Norte e Noroeste Fluminense do Estado do Rio de Janeiro. Essa cultivar possui hábito de crescimento indeterminado (tipo IV) e porte trepador, características de interesse por atingirem maiores produções. Apresenta dupla aptidão, sendo destinada tanto para o consumo da vagem fresca quanto da vagem seca, com produtividade de grãos desejável, em torno de 4,28 t ha-1. Além de sua versatilidade de uso, possui ciclo e velocidade de desenvolvimento do hábito trepador médio; número médio de vagens equivalente a 83,93; comprimento médio de vagem de 15cm; grau de curvatura fraca a média, e grau de ternura média. Ensaios para o pedido de proteção da cultivar estão sendo concluídos com a finalidade de realizar sua produção e distribuição.

This work describes a comparative molecular structure of two hydroxychlorochalcones with an emphasis on their planarity. Hirshfeld surface analysis investigates the effect of ortho- and para-chlorine substitution on supramolecular arrangement and physical chemical properties. The molecular conformation of 2′-hydroxy-4′,6′-dimethyl-2-chlorochalcone and 2′-hydroxy-4′,6′-dimethyl-4-chlorochalcone chalcones was obtained through DFT with the exchange-correlation functional M06-2X and the 6-311++G(2d,2p) basis set, and the results were compared with the experimental X-ray data in order to get insights on the effect of ortho- and para-chlorine substitution. The charge transfer into entire main carbon chain was also investigated using frontier molecular orbitals (HOMO and LUMO), NBO, and MEP map in order to describe the comparative conformational stability due to the resonance effect produced by π electron displacements. Finally, the intermolecular observed interactions were analyzed by QTAIM, with the M06-2X/6-311G++(d,p) theory level.

Anthracene derivatives are an interesting class of compounds and modifications in the anthracene ring, producing different compounds with different properties. Structural analysis of anthracene derivatives with modifications in position 9,10 of the aromatic ring is necessary in order to obtain information about its properties. The introduction of groups with polar substituents increases the possibility to modify the molecule lipophilicity, corroborating its use as bioimaging probes. Anthracene derivatives are used in many biochemical applications. These compounds can react with molecular singlet oxygen [O2 (1Δg)], a reactive oxygen species, through the Diels–Alder reaction [4 + 2] to form the respective endoperoxide and to be used as a chemical trap in biological systems. Thus, the structural and crystalline characterizations of two anthracene derivatives are presented in this work to obtain information about their physical-chemical properties. The compounds were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analyses and scanning electron microscopy. The molecular structures of the compounds were studied by the Density Functional Theory, M06-2X/6-311++G(d,p) level of theory in the gas phase. From the results obtained for the frontier molecular orbitals, HOMO and LUMO, and from the Molecular Electrostatic Potential map, it was possible to predict the chemical properties of both compounds. The supramolecular arrangements were also theoretically studied, whose molecules were kept fixed in their crystallographic positions, through the natural bonding orbitals analysis to check the stability of interactions and the quantum theory of atoms in molecules to verify the type of intermolecular interaction between their molecules, as well as how they occur.

This work describes molecular structures of chalcones 2'-Hydroxy-4',6'-dimethyl-2-chlorochalcone and 2'-Hydroxy-4',6'-dimethyl-4-chlorochalcone and overlap of these structures in order to detect the change in planarity. The Hirshfeld Surface analysis to investigate when the position of the atom the chlorine in the aromatic ring is changed and how does this change influence in the properties of the organic compound. The geometric molecular were obtained through the DFT/M06-2X/6-311++G(2d, 2p) theory level. Frontier Molecular Orbital, NBO and MEP map were determined, in order to observe the information related to charge transfer in the molecule. The interactions between the molecules were verified with the aid of QTAIM.

This work describes a comparative molecular structure of two hydroxychlorochalcones with an emphasis on their planarity. Hirshfeld surface analysis investigates the effect of ortho- and para-chlorine substitution on supramolecular arrangement and physical chemical properties. The molecular conformation of 2'-hydroxy-4',6'-dimethyl-2-chlorochalcone and 2'-hydroxy-4',6'-dimethyl-4-chlorochalcone chalcones was obtained through DFT with the exchange-correlation functional M06-2X and the 6-311++G(2d,2p) basis set, and the results were compared with the experimental X-ray data in order to get insights on the effect of ortho- and para-chlorine substitution. The charge transfer into entire main carbon chain was also investigated using frontier molecular orbitals (HOMO and LUMO), NBO, and MEP map in order to describe the comparative conformational stability due to the resonance effect produced by π electron displacements. Finally, the intermolecular observed interactions were analyzed by QTAIM, with the M06-2X/6-311G++(d,p) theory level.

Enterotoxigenic Escherichia coli (ETEC) represents one of the most important etiological agents of diarrhea in developing countries and characteristically produces at least one of two enterotoxins: heat-labile toxin (LT) and heat-stable toxin (ST). It has been previously shown that the production and release of LT by human-derived ETEC strains are variable. Although the natural genetic polymorphisms of regulatory sequences of LT-encoding (eltAB) genes may explain the variable production of LT, the knowledge of the transcriptional and posttranscriptional aspects affecting LT expression among ETEC strains is not clear. To further understand the factors affecting LT expression, we evaluated the impact of the natural polymorphism in noncoding regulatory sequences of eltAB among clinically derived ETEC strains. Sequence analyses of seven clinically derived strains and the reference strain H10407 revealed polymorphic sites at both the promoter and upstream regions of the eltAB operon. Operon fusion assays with GFP revealed that specific nucleotide changes in the Pribnow box reduce eltAB transcription. Nonetheless, the total amounts of LT produced by the tested ETEC strains did not strictly correspond to the detected LT-specific mRNA levels. Indeed, the stability of LT varied according to the tested strain, indicating the presence of posttranscriptional mechanisms affecting LT expression. Taken together, our results indicate that the production of LT is a strain-specific process and involves transcriptional and posttranscriptional mechanisms that regulate the final amount of toxin produced and released by specific strains. Electronic supplementary material The online version of this article (10.1007/s42770-020-00231-2) contains supplementary material, which is available to authorized users.

The Nuclear Engineering Department of the Military Institute of Engineering (SE/7-IME) is designing and simulation a neutron irradiator with 1 Ci of 241Am-9Be source. The objective of this irradiator is to generate a flux of neutrons to be used in research and teaching maintaining, for purposes of radiological protection, the rate of ambient dose equivalent, H*(10), below 10 μSv/h at 30 cm from the surface. This paper presents the proposed irradiator, values of H*(10) at different distances from the irradiator and the neutron flux in different points of the beam irradiation, all calculated using the MCNPX code.

Made available in DSpace on 2018-12-11T17:08:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-02-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Stress perception and signalling pathways between plant organs involve complex mechanisms and remain a major focus of interest. To further address the role of phytohormones in the modulation of stress perception from root-to-shoot signalling, we used ethylene-insensitive Never ripe (Nr) and auxin-insensitive diageotropica (dgt) tomato mutants combined with the grafting technique. Lipid peroxidation, H2O2, chlorophyll and proline contents, and activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) in non-grafted and grafted tomato mutants subjected to cadmium (Cd) were analysed. The results revealed different responses according to genotype, grafting combination and Cd application. Non-grafted hormonal mutants exhibited higher Cd content in roots than MT plants, being 39.9% in Nr and 17.7% in dgt plants, whereas in leaves, the Cd content was higher in Nr plants. In grafted plants, where the rootstocks were exposed to Cd before grafting, the MT rootstock exhibited the highest Cd content. In non-grafted plants following Cd application, roots of Nr also exhibited a decrease in Ca concentration, whilst Mg, S, Cu and Zn decreased in Nr leaves. In grafted plants, it was possible to notice peculiar differences in nutrient concentration patterns according to grafting combination and Cd application. The proline and chlorophyll contents were less affected in the hormonal mutants. In the presence of Cd, the scions of grafted plants exhibited increased antioxidant enzymes activities in response to a signal from the rootstocks. However, it was possible to associate the involvement of ethylene and auxin with the antioxidant responses because the Nr and dgt genotypes were less affected by Cd stress than their wild-type counterpart, MT. UNESP — Univ. Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias-FCAV Depto. de Biologia Aplicada à Agropecuária (DBAA), Jaboticabal Unifeob — Centro Universitário da Fundação de Ensino Octávio Bastos, São João da Boa Vista USP — Universidade de São Paulo Escola Superior de Agricultura Luiz de Queiroz-ESALQ Depto. de Genética UNESP — Univ. Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias-FCAV Depto. de Biologia Aplicada à Agropecuária (DBAA), Jaboticabal FAPESP: 2013/27080-4

Cystoisospora felis is a coccidian parasite commonly found in feces of domestic cats. Infection in cats occurs by ingestion of sporulated oocysts or consumption of rodents infected by the parasite. Scarce information is available about extraintestinal stages of C. felis in naturally infected intermediate hosts, as well as in cell culture. The aim of the current work was to investigate the development of C. felis in Vero cells (African green monkey kidney) and MDCK cells (Madin-Darby canine kidney). Cell monolayers were inoculated with mechanically released sporozoites of C. felis, and parasite growth was daily examined using light microscopy. After cell invasion, only parasitophorous vacuoles containing a single zoite were observed. Five days post-inoculation with sporozoites, unstained cell monolayers were evaluated by differential interference contrast (DIC), and also by Romanovsky stain using conventional light microscopy. Single zoites, each surrounded by a cyst wall, were observed by both methods. Multiplication by endodyogeny did not occur in any cell monolayer. Treatment of encysted parasites with HCl-pepsin for 15 min led to dissolution of the cyst wall and release of intact and motile zoites. To our knowledge, this is the first demonstration of in vitro production of monozoic tissue cysts of C. felis. As kittens commonly shed C. felis in their feces, oocysts are easily available for in vitro production of monozoic tissue cysts of the parasite. Development of C. felis in cell culture may be employed as a model on tissue cyst formation of Cystoisospora spp. and closely related coccidia.

Many aspects related to ROS modulation of signaling networks and biological processes that control stress responses still remain unanswered. For this purpose, the grafting technique may be a powerful tool to investigate stress signaling and specific responses between plant organs during stress. In order to gain new insights on the modulation of antioxidant stress responses mechanisms, gas-exchange measurements, lipid peroxidation, H2O2 content, proline, superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), ascorbate peroxidase (APX) and guaiacol peroxidase (GPOX) were analyzed in Micro-Tom grafted plants submitted to cadmium (Cd). The results observed revealed that higher amounts of Cd accumulated mainly in the roots and rootstocks when compared to leaves and scions. Macronutrients uptake (Ca, S, P and Mg) decreased in non-grafted plants, but differed among plant parts in all grafted plants. The results showed that the accumulation of proline observed in scions of grafted plants could be associated to the lower MDA contents in the scions of grafted plants. In the presence of Cd, non-grafted plants displayed increased CAT, GR, GPOX and APX activities for both tissues, whilst grafted plants revealed distinct trends that clearly indicate signaling responses from the rootstocks, allowing sufficient time to activate defense mechanisms in shoot. The information available concerning plants subjected to grafting can provide a better understanding of the mechanisms of Cd detoxification involving root-to-shoot signaling, opening new possibilities on strategies which can be used to manipulate heavy metal tolerance, since antioxidant systems are directly involved in such mechanism.

Cracking nuts with tools is a behavior documented in a small number of populations of tufted capuchins, mainly in semi-arid Caatinga and Caatinga–Cerrado transitional environments of northeastern Brazil. Only one of these populations inhabits the less arid Cerrado in Central Brazil, where environments are composed of a heterogeneous mosaic of fields, savannas and forest formations. We conducted surveys in 10 of 20 localities where nutcracking by capuchins was reported by the local inhabitants in the Cerrrado of Northern Goias and Tocantins. Our purpose was to evaluate nutcracking sites (anvils and associated hammers and nuts) based on indirect evidence of extensive pounding of nuts and seeds. Nutcracking was confirmed at all 10 surveyed localities. A total of 270 sites were identified. Surveyed localities included areas that were ecologically similar to those where capuchins crack nuts in Caatinga, as well as less arid localities with more typical Cerrado habitat. Anvils and hammers were made of materials including quartz, limestone, sandstone and wood, and displayed a wider range of sizes (i.e., 60–3,750 g for hammers’ weight) than reported at previously studied localities. Nuts of seven genera were found in association with anvils and hammers. We conclude that nutcracking by capuchins are not restricted to arid environments and argue that the occurrence and diversity of nutcracking tool sites result from complex interactions of environmental variables (e.g., availability of food and mineral resources, density of canopy cover) and social variables (e.g., spatial cohesiveness and tolerance among group members) that need to be examined through long-term research of habituated groups. Localities in the Cerrado of Northern Goias and Tocantins vary considerable in the ecological conditions faced by wild groups, and therefore offer the opportunity to examine these interactions. Am. J. Primatol. 77:535–546, 2015. © 2015 Wiley Periodicals, Inc.

The yeast exosome is a conserved multiprotein complex essential for RNA processing and degradation. The complex is formed by a nine-subunit core that associates with two hydrolytic 3'-5' exoribonucleases. Although catalytically inert, the assembly of this nine-subunit core seems to be essential for the exosome activity, as mutations in regions that do not directly bind RNA or are not in the active sites of the exonucleases impair the function of the complex. Previously isolated mutations in the exosome core subunit Rrp43p have been shown to negatively affect the function of the complex. With the aim of investigating the effect of these mutations on the complex stability and activity, Rrp43p and its mutant forms were purified by means of the TAP method. Mass spectrometry analyses showed that lower amounts of the exosome subunits are copurified with the mutant Rrp43p proteins. Additionally, by decreasing the stability of the exosome, other nonspecific protein interactions are favored (the data have been deposited to the ProteomeXchange with identifier PXD000580). Exosome copurified with mutant Rrp43p exhibited increased exonuclease activity, suggesting higher dissociation constants for these mutant complexes. Therefore, data reported here indicate that complexes containing a mutant Rrp43p exhibit decreased stability and provide information on additional protein interactions.

In this paper, we present approximate distributions for the ratio of the cumulative wavelet periodograms considering stationary and non-stationary time series generated from independent Gaussian processes. We also adapt an existing procedure to use this statistic and its approximate distribution in order to test if two regularly or irregularly spaced time series are realizations of the same generating process. Simulation studies show good size and power properties for the test statistic. An application with financial microdata illustrates the test usefulness. We conclude advocating the use of these approximate distributions instead of the ones obtained through randomizations, mainly in the case of irregular time series.

Extraction of a signal in the presence of stochastic noise via wavelet shrinkage has been studied under assumptions that the noise is independent and identically distributed (IID) and that the samples are equispaced (evenly spaced in time). Previous work has relaxed these assumptions either to allow for correlated observations or to allow for random sampling, but very few papers have relaxed both together. In this paper we relax both assumptions by assuming the noise to be a stationary Gaussian process and by assuming a random sampling scheme dictated either by a uniform distribution or by an evenly spaced design subject to jittering. We show that, if the data are treated as if they were autocorrelated and equispaced, the resulting wavelet-based shrinkage estimator achieves an almost optimal convergence rate. We investigate the efficacy of the proposed methodology via simulation studies and illustrate it by the extraction of the light curve for a variable star.

Cadmium (Cd) is an important metal due to its industrial use but also one of the most dangerous metals because of its accumulation in the environment. This can eventually lead to entrance into the food chain if the Cd is taken up by crop plants used for feeding animals and humans. Thus, a large number of reviews have discussed the many aspects of stress induced by Cd and other metals in a wide range of species. In relation to plants, useful reviews have been published over the years regarding molecular and biochemical aspects of Cd stress. In this minireview, we have concentrated on promising and emerging topics of Cd-stress research in plants, such as hormonal control of the antioxidant system and interaction between organisms and plants.

The objective of this study was to identify dermatoglyphic characteristics and the quality of the physical strength in high-performance para-athletes in the supine power lifting category. This study included ten male athletes aged between 18 and 40 years who had qualified for the Brazilian Regional Championships. The athletes were randomly distributed into the following three groups: group 1 (n = 4) comprising athletes with the best results for relative strength, group 2 (n = 4) comprising athletes with intermediate results for relative strength, and group 3 (n = 2) comprising athletes with the lowest results for relative strength. To determine the strength potential of the athletes, the one repetition maximum test was chosen, and to identify their genetic profile their fingerprints were analyzed by the method of Cummins and Midlo using paper and ink. The data showed no homogeneity between the groups. Group 1 showed a higher genetic predisposition and better results for the quality of their physical strength. These results indicate that dermatoglyphics may be an important tool to identify and guide athletes according to their genetic potential.

In order to further address the known interaction between ethylene and components of the oxidative system, we have used the ethylene-insensitive Never ripe ( Nr ) tomato ( Solanum lycopersicum L.) mutant, which blocks ethylene responses. The mutant was compared to the control Micro-Tom (MT) cultivar subjected to two stressful situations: 100 mM NaCl and 0.5 mM CdCl 2 . Leaf chlorophyll, lipid peroxidation and antioxidant enzyme activities in roots, leaves and fruits, and Na and Cd accumulation in tissues were determined. Although we verified a similar growth pattern and Na and Cd accumulation for MT and Nr , the mutant exhibited reduced leaf chlorophyll degradation following stress. In roots and leaves, the patterns of catalase (CAT), glutathione reductase (GR), ascorbate peroxidase (APX), guaiacol peroxidase (GPOX), superoxide dismutase (SOD) enzyme activity as well as malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2 ) production under the stressful conditions tested were very similar between MT and Nr mutant. However, Nr fruits showed increased H 2 O 2 production, reduced and enhanced APX activity in NaCl and CdCl 2 , respectively, and enhanced GPOX in NaCl. Moreover, through non-denaturing PAGE, a similar reduction of SOD I band intensity in both, control MT and Nr mutant, treated with NaCl was observed. In leaves and fruits, a similar SOD activity pattern was observed for all periods, genotypes and treatments. Overall the results indicate that the ethylene signaling associated with NR receptor can modulate the biochemical pathways of oxidative stress in a tissue dependent manner, and that this signaling may be different following Na and Cd exposure.

The extracytoplasmic function sigma factor σ T is the master regulator of general stress response in Caulobacter crescentus and controls the expression of its paralogue σ U . In this work we showed that PhyR and NepR act, respectively, as positive and negative regulators of σ T expression and function. Biochemical data also demonstrated that NepR directly binds σ T and the phosphorylated form of PhyR. We also described the essential role of the histidine kinase gene CC3474, here denominated phyK, for expression of σ T -dependent genes and for resistance to stress conditions. Additionally, in vivo evidence of PhyK-dependent phosphorylation of PhyR is presented. This study also identified a conserved cysteine residue (C95) located in the periplasmic portion of PhyK that is crucial for the function of the protein. Furthermore, we showed that PhyK, PhyR and σ T regulate the same set of genes and that σ T apparently directly controls most of its regulon. In contrast, σ U seems to have a very modest contribution to the expression of a subset of σ T -dependent genes. In conclusion, this report describes the molecular mechanism involved in the control of general stress response in C. crescentus.

Nitrogen uptake and metabolism are essential to microbial growth. Gat1 belongs to a conserved family of zinc finger containing transcriptional regulators known as GATA-factors. These factors activate the transcription of Nitrogen Catabolite Repression (NCR) sensitive genes when preferred nitrogen sources are absent or limiting. Cryptococcus neoformans GAT1 is an ortholog to the Aspergillus nidulans AreA and Candida albicans GAT1 genes. In an attempt to define the function of this transcriptional regulator in C. neoformans, we generated null mutants (gat1Δ) of this gene. The gat1 mutant exhibited impaired growth on all amino acids tested as sole nitrogen sources, with the exception of arginine and proline. Furthermore, the gat1 mutant did not display resistance to rapamycin, an immunosuppressant drug that transiently mimics a low-quality nitrogen source. Gat1 is not required for C. neoformans survival during macrophage infection or for virulence in a mouse model of cryptococcosis. Microarray analysis allowed the identification of target genes that are regulated by Gat1 in the presence of proline, a poor and non-repressing nitrogen source. Genes involved in ergosterol biosynthesis, iron uptake, cell wall organization and capsule biosynthesis, in addition to NCR-sensitive genes, are Gat1-regulated in C. neoformans.

Sugarcane is now an extremely important crop, particularly in tropical countries. Its use for sugar and ethanol production is critical and cultivated area and biomass yield are increasing. Environmental pollution by anthropogenic activities is perhaps one of the most disturbing problems the world is facing and the cultivation of crops is subjected to this pollution, which may result in drastic effects on crop production. Curiously, the literature on the study of abiotic stresses on sugarcane is very limited, indicating that there is far more research to be done and investigations on this topic need to be prioritized. In this article, we have tried to focus on four key abiotic stresses, drought, temperature, salt and toxic metals, to which sugarcane is most likely to be subjected and reviewed the scarce current literature on the subject.

Tomato high pigment (hp) mutants represent an interesting horticultural resource due to their enhanced accumulation of carotenoids, flavonoids and vitamin C. Since hp mutants are known for their exaggerated light responses, the molecules accumulated are likely to be antioxidants, recruited to deal with light and others stresses. Further phenotypes displayed by hp mutations are reduced growth and an apparent disturbance in water loss. Here, we examined the impact of the hp1 mutation and its near isogenic line cv Micro-Tom (MT) on stomatal conductance (gs), transpiration (E), CO2 assimilation (A) and water use efficiency (WUE). Detached hp1 leaves lost water more rapidly than control leaves, but this behaviour was reversed by exogenous abscisic acid (ABA), indicating the ability of hp1 to respond to this hormone. Although attached hp1 leaves had enhanced gs, E and A compared to control leaves, genotypic differences were lost when water was withheld. Both instantaneous leaf-level WUE and long-term whole plant WUE did not differ between hp1 and MT. Our results indicate a link between exaggerated light response and water loss in hp1, which has important implications for the use of this mutant in both basic and horticultural research.

Good reviews have been published over the years regarding many aspects of plant response to light, such as important advances in understanding the molecular mechanisms of light perception, signaling and control of gene expression by the photoreceptors. Moreover, many efforts have been undertaken on the manipulation of these mechanisms to improve horticultural crop production. In this paper we present an overview about the photoreceptors, the relationship between their absorptive and reflective properties and their control of plant development as well perspectives focused on photomorphogenesis manipulation.

Esse artigo descreve e analisa relações que emergem da atuação dos profissionais do Programa Mais Médicos para o Brasil na saúde indígena do Tocantins, a partir do contato desses profissionais com o povo Akw?/Xerente. Recorreu-se aos relatos de profissionais e de indígenas Xerente, coletados na área indígena onde atuam e nos novos espaços que surgem pela dinâmica do Programa. Dessa zona de contato entre profissionais e indígenas emergiram novas formas de relacionamento. Fatores como permanência dos profissionais, formação adequada e disponibilidade foram importantes para a interação desses profissionais com a comunidade contribuindo para uma relação mais simétrica. De outro lado, o processo histórico de relação dos Xerente com a sociedade circundante consistiu num elemento facilitador dessa relação.

Hormones are molecules involved in virtually every step of plant development and studies in this field have been shaping plant physiology for more than a century. The model plant Arabidopsis thaliana, long used as a tool to study plant hormones, lacks significant important developmental traits, such as fleshy climacteric fruit, compound leaf and multicellular trichomes, suggesting the necessity for alternative plant models. An attractive option often used is tomato, a species also of major economic importance, being ideal to bring together basic and applied plant sciences. The tomato Micro-Tom (MT) cultivar makes it possible to combine the direct benefits of studying a crop species with the fast life cycle and small size required for a suitable biological model. However, few obscure questions are constantly addressed to MT, creating a process herein called "MT mystification". In this work we present evidence clarifying these questions and show the potential of MT, aiming to demystify it. To corroborate our ideas we showed that, by making use of MT, our laboratory demonstrated straightforwardly new hormonal functions and also characterized a novel antagonistic hormonal interaction between jasmonates and brassinosteroids in the formation of anti-herbivory traits in tomato.

The nonlocal nonlinearity of castor oil was investigated using the Z-scan technique in the CW regime at 514 nm and in femtosecond regime at 810 nm. Large negative nonlinear refractive indexes of thermal origin, thermo-optical coefficients and degree of nonlocality were obtained for both laser excitation wavelengths. The results indicate that the electronic part of the nonlinear refractive index and nonlinear absorption were negligible. Our results suggest that castor oil is promising candidate as a nonlinear medium for several nonlocal optical applications, such as in spatial soliton propagation, as well as a dispersant agent in the measurement of absorptive properties of nanoparticles.

Flow pumps have been developed for classical applications in Engineering, and are important instruments in areas such as Biology and Medicine. Among applications for this kind of device we notice blood pump and chemical reagents dosage in Bioengineering. Furthermore, they have recently emerged as a viable thermal management solution for cooling applications in small-scale electronic devices. This work presents the performance study of a novel principle of a piezoelectric flow pump which is based on the use of a bimorph piezoelectric actuator inserted in fluid (water). Piezoelectric actuators have some advantages over classical devices, such as lower noise generation and ease of miniaturization. The main objective is the characterization of this piezoelectric pump principle through computational simulations (using finite element software), and experimental tests through a manufactured prototype. Computational data, such as flow rate and pressure curves, have also been compared with experimental results for validation purposes.

Sigma factors of the ECF subfamily are important regulators of stress responses in bacteria. Analysis of Caulobacter crescentus genome sequence has indicated the presence of 13 members of the ECF (extracytoplasmic function) subfamily, suggesting that these regulators play an important role in C. crescentus physiology. This work describes the characterization of two highly similar C. crescentus ECF sigma factors, sigma(U) and sigma(T). The corresponding genes are not essential under normal growth conditions and absence of sigma(U) does not impair bacterial resistance to the environmental stresses tested. However, absence of sigma(T) significantly affects the ability of C. crescentus cells to survive osmotic and oxidative stress. Using transcription fusions to sigT and sigU upstream regions we demonstrate that both genes are induced by osmotic stress in a sigma(T)-dependent manner. Determination of sigU and sigT transcription start sites revealed an identical promoter motif, typical of ECF-dependent promoters. Transcriptome analysis revealed 40 putative members of the sigma(T) regulon, including sigU and sigR, encoding another ECF subfamily member, and genes involved in general stress responses and cell envelope functions. Twenty of those genes exhibit the sigT/sigU promoter motif in their upstream regions. Our data indicate a role of sigma(T) in distinct stress responses in C. crescentus.

Background As bacterial cells enter stationary phase, they adjust their growth rate to comply with nutrient restriction and acquire increased resistance to several stresses. These events are regulated by controlling gene expression at this phase, changing the mode of exponential growth into that of growth arrest, and increasing the expression of proteins involved in stress resistance. The two-component system SpdR/SpdS is required for the activation of transcription of the Caulobacter crescentus cspD gene at the onset of stationary phase. Results In this work, we showed that both SpdR and SpdS are also induced upon entry into stationary phase, and this induction is partly mediated by ppGpp and it is not auto-regulated. Global transcriptional analysis at early stationary phase of a spdR null mutant strain compared to the wild type strain was carried out by DNA microarray. Twenty-three genes showed at least twofold decreased expression in the spdR deletion mutant strain relative to its parental strain, including cspD, while five genes showed increased expression in the mutant. The expression of a set of nine genes was evaluated by quantitative real time PCR, validating the microarray data, and indicating an important role for SpdR at stationary phase. Several of the differentially expressed genes can be involved in modulating gene expression, including four transcriptional regulators, and the RNA regulatory protein Hfq. The ribosomal proteins NusE and NusG, which also have additional regulatory functions in transcription and translation, were also downregulated in the spdR mutant, as well as the ParE1 toxin. The purified SpdR protein was shown to bind to the regulatory region of CC0517 by Electrophoretic Mobility Shift Assay, and the SpdR-regulated gene CC0731 was shown to be expressed at a lower level in the null cspD mutant, suggesting that at least part of the effect of SpdR on the expression of this gene is indirect. Conclusions The results indicate that SpdR regulates several genes encoding proteins of regulatory function, which in turn may be required for the expression of other genes important for the transition to stationary phase. Electronic supplementary material The online version of this article (doi:10.1186/s12866-016-0682-y) contains supplementary material, which is available to authorized users.

EIF5A1 protein has a particular amino acid residue, named hypusine, that has never been found in others proteins and is highly conserved in Archaea and Eukarya domains. The hypusine is essential fo...

Background With the aim of remaining viable, bacteria must deal with changes in environmental conditions, including increases in external osmolarity. While studies concerning bacterial response to this stress condition have focused on soil, marine and enteric species, this report is about Caulobacter crescentus, a species inhabiting freshwater oligotrophic habitats. Results A genomic analysis reported in this study shows that most of the classical genes known to be involved in intracellular solute accumulation under osmotic adaptation are missing in C. crescentus. Consistent with this observation, growth assays revealed a restricted capability of the bacterium to propagate under hyperosmotic stress, and addition of the compatible solute glycine betaine did not improve bacterial resistance. A combination of transcriptomic and proteomic analyses indicated quite similar changes triggered by the presence of either salt or sucrose, including down-regulation of many housekeeping processes and up-regulation of functions related to environmental adaptation. Furthermore, a GC-MS analysis revealed some metabolites at slightly increased levels in stressed cells, but none of them corresponding to well-established compatible solutes. Conclusion Despite a clear response to hyperosmotic stress, it seems that the restricted capability of C. crescentus to tolerate this unfavorable condition is probably a consequence of the inability to accumulate intracellular solutes. This finding is consistent with the ecology of the bacterium, which inhabits aquatic environments with low nutrient concentration. Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0404-x) contains supplementary material, which is available to authorized users.

Photoperiod controls many plant developmental responses, including tuber formation in potato (Solanum tuberosum L.) plants. Photoperiodic stimuli are received by phytocromes in the leaves and must be conveyed to the underground portion of the plant for the tubers to develop, but the nature of the signal responsible for this is hitherto unknown. Plant hormones are known to have a role in tuber formation, through a series of complex interactions between them and with other substances. Here, some accessions from the large collection of hormone and photomorphogenic mutants in tomato (Lycopersicon esculentum Mill.) were used to study the process of tuberization through grafting onto potato rootstocks. The chosen photomorphogenic mutants were aurea (au, chromophore deficient), far red insensitive ( fri, PHYA deficient), temporary red insensitive (tri, PHYB1 deficient) and high pigment (hp, exaggerated phytochrome response), as well as the hormone mutants gibberellin deficient-1 (gib-1), dwarf (d, brassinosteroid deficient), diageotropica (dgt, auxin insensitive), notabilis (not, ABA deficient), procera ( pro, gibberellin hypersensitive). Tuber number, tuber and shoot dry weight and sprouting were quantified as a measure of the tuber induction capability of each genotype. Tomato scions were always less effective to promote tuberization than the potato scions. Among photomorphogenic mutants, the highest tuberization was achieved with the chromophore deficient (au). The tuber induction capability was (in decreasing order) d, gib-1, dgt, not and pro for hormone mutants. A clear-cut negative correlation (r = 0.98) was observed between dry tuber weight and dry shoot weight. Sprouting also varied to a large extent, the most sprouting-inducer was the gibberellin deficient scion. These results lead us to suggest that source–sink relationship, which is affected by both hormones and photomorphogenesis, has a pivotal role in tuber formation and that tomato scions fail to produce a substance(s) involved in the convertion of the stolon into the strong sink that forms the tuber. # 2005 Elsevier Ireland Ltd. All rights reserved.

The in vitro regeneration ability of tomato (Lycopersicon esculentumMill.) remains the main limiting factor for efficient genetic transformation. However, competence for in vitro regeneration can be transferred from wild Lycopersicon species to the cultivated tomato. The high regeneration capacity presented by the MsK genotype, derived from L. peruvianum, was attributed to the dominant loci Rg-1 and Rg-2 .I n the present work, we have transferred the high organogenetic competence from the MsK genotype to the cultivar Micro-Tom, which presents miniature size (8-cm tall) and a rapid life cycle (75 days from seed to fruit ripening). We obtained stable and non-segregating F6 ‘Micro-MsK’ plants, which were expressively superior to Micro-Tom in regeneration capacity, when hypocotyls but not cotyledons were used as explants. In addition to the regeneration ability, the obtained genotype presented a delayed leaf senescence and a reduced apical dominance. The development of ‘Micro-MsK’ genotype will enable the application of insertional mutagenesis in functional genomics of tomato. © 2004 Elsevier Ireland Ltd. All rights reserved.

Cracking nuts with tools is a behavior documented in a small number of populations of tufted capuchins, mainly in semi-arid Caatinga and Caatinga-Cerrado transitional environments of northeastern Brazil. Only one of these populations inhabits the less arid Cerrado in Central Brazil, where environments are composed of a heterogeneous mosaic of fields, savannas and forest formations. We conducted surveys in 10 of 20 localities where nutcracking by capuchins was reported by the local inhabitants in the Cerrrado of Northern Goiás and Tocantins. Our purpose was to evaluate nutcracking sites (anvils and associated hammers and nuts) based on indirect evidence of extensive pounding of nuts and seeds. Nutcracking was confirmed at all 10 surveyed localities. A total of 270 sites were identified. Surveyed localities included areas that were ecologically similar to those where capuchins crack nuts in Caatinga, as well as less arid localities with more typical Cerrado habitat. Anvils and hammers were made of materials including quartz, limestone, sandstone and wood, and displayed a wider range of sizes (i.e., 60-3,750 g for hammers' weight) than reported at previously studied localities. Nuts of seven genera were found in association with anvils and hammers. We conclude that nutcracking by capuchins are not restricted to arid environments and argue that the occurrence and diversity of nutcracking tool sites result from complex interactions of environmental variables (e.g., availability of food and mineral resources, density of canopy cover) and social variables (e.g., spatial cohesiveness and tolerance among group members) that need to be examined through long-term research of habituated groups. Localities in the Cerrado of Northern Goiás and Tocantins vary considerable in the ecological conditions faced by wild groups, and therefore offer the opportunity to examine these interactions.

The effects of litter size on maternal care, body weight and infant development of golden hamsters were investigated from a longitudinal perspective. Litters were culled to 1, 3, 6 and 9 pups, and the behavior and body weight of mothers and pups were recorded from the 5th to the 25th postpartum day. We noted that the time spent by mothers in bodily interactions with pups decreased as a function of litter size; maternal pup retrievals reached their maximum around the 13–15th day, which coincided with the increased locomotor activity of pups at this time; the total number of pup retrievals by the mother increased as a function of the litter size, but mothers of larger litters were more ‘efficient’ (i.e. they failed less frequently in exhibiting a full sequence of retrievals) and exhibited a low litter-size proportional mean number of retrievals. All mothers gradually lost body mass throughout lactation, and decrease in body weight was significantly related to litter size. The mean body weight gain (%) by pups decreased as a function of litter size, but we also noted that single and larger litter pups exhibited a decreased body mass (grams) by the 15th day, suggesting that infant development may be impaired at both extremes of experimental conditions. We concluded that the behavior of mothers and pups was affected by the litter size, and it appeared that the litter had an optimal size—not so large as to overlap the mother's physical capacity, and not so small as to fail to compensate for the parental investment.

A influência do inglês como lingua franca é enorme em diferentes contextos, como pode ser visto nas artes (música, cinemae literatura), ciência e tecnologia, atividades empresariais e relações diplomáticas. Uma língua comum é um instrumento valioso no mundo moderno, pois ela facilita a comunicação entre pessoas de diferentes culturas, mas, não obstante essas vantagens,alguns intelectuais argumentam que a influência do idioma inglês representa uma ameaça à diversidade cultural. A predominância do idioma inglês é recente, pois o Latim era preferido dos filósofos e cientistas dos tempos medievais e também foi adotado como idioma oficial da Igreja Católica– tal influência persiste, pois todos os nomes científicos de plantas e animais são escritos nesse idioma. A influência do idioma francês aumentou com o tempo, mas o fenômeno logo deu lugar à “americanização” da cultura ocidental que ocorreu após a II Guerra Mundial. Foram examinadas a função da lingua franca em múltiplos contextos e a crescente dominação da cultura americana na língua portuguesa.