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The mesoscale activity of western boundary currents can induce changes in the oligotrophic conditions of the oceanic subtropical gyres. Off SE Brazil, recurrent meanders in the Brazil Current can modulate the pelagic ecosystem through eddy‐induced upwelling, as well as drive coastal upwelling and cross‐shelf exchanges. Despite their relevance, direct measurements of such meanders are scarce. At the end of the Spring of 2019, we acquired measurements of both physical and biogeochemical properties along a transect through one of these features, with 5–10 km spacing between stations. Displacements of the isopycnals at the meander edges arose from submesoscale filaments along the meander's rim, associated with the signature of shelf water masses. Chlorophyll distributions along the transect indicated phytoplankton responses to the different dynamic regimes in the meander: eddy stirring in the surface mixed layers versus eddy pumping in the subsurface waters, and mesoscale dynamics in the meander center versus submesoscale dynamics in its periphery. Subsurface phytoplankton biomass was enhanced in the meander center, likely due to eddy pumping raising the nutricline into the euphotic zone. Eddy pumping also appears to have contributed to a shift in the phytoplankton community composition to larger organisms. Our results indicate that the physical dynamics create different habitats across the meander, leading to spatial patchiness in the chlorophyll distributions, with different types of organisms in distinct parts of the meander. Plain Language Summary: Like rivers, ocean currents can meander along their paths. Off southeastern Brazil, the Brazil Current flows southward and meanders as it flows past capes in the region. These meanders are hundreds of kilometers wide (mesoscale) and can generate smaller features that are tens of kilometers wide (submesoscale). These multiscale processes impact the planktonic ecosystem by inducing nutrient inputs to the nutrient‐poor open ocean and consequently enhancing primary productivity. However, direct measurements of these features are scarce. We had the opportunity to survey one of these meanders in 2019, collecting physical and biogeochemical data along a single line through the meander from southwest to northeast. We found small‐scale distortions that indicated the presence of submesoscale features swirling around the meander's rim. Different parts of the meander showed distinct phytoplankton responses, with more phytoplankton in the center, below the surface, likely growing on nutrients pumped upward by the meander. This pumping process might have been correlated with a phytoplankton community shift from small to larger organisms. Overall, our study shows that mesoscale and submesoscale motions create a variety of habitats, leading to distinct chlorophyll distribution patterns in different parts of the meander. Key Points: We present the first physical‐biological measurements of a Brazil Current cyclonic meander drawing high chlorophyll shelf waters offshoreEddy pumping raised nutricline to the euphotic zone driving subsurface phytoplankton enhancement at eddy center and invisible to satellitesDistinct hydrodynamic regimes modulated the phytoplankton response in the center, rim, surface, and subsurface of the eddy [ABSTRACT FROM AUTHOR]

This work describes the circulation over the continental slope and the São Paulo Plateau in the Santos Basin during the SANSED winter 2019 survey. The cruise consisted of four legs in the period between June, 11 and August, 03 2019. The observed circulation is dominated by the Atlantic southwestern boundary current regime and remotely-generated anticyclones and cyclones. The former is composed by the Brazil Current, the Intermediate Western Boundary Current and their mesoscale meanders; the latter are 300km vortical rings with origin in the eastern side of the South Atlantic Basin. A Lagrangian scheme applied over satellite altimeter maps indicate that the origin of these rings is primarily the Cape Basin off South Africa. The interaction between the boundary currents, their cyclonic meanders, and the anticyclonic rings is complex, and varies widely. During the SANSED winter 2019 survey period, three anticyclones interacted with the Brazil Current, instabilizing it, forming dipoles with the current cyclonic meanders, leading to their downstream propagation. Ancienter cyclonic eddies within Santos Basin may interfere with the propagation of the large anticyclones further south. In addition, the continuous arrival of remotely-originated anticyclones, the larger portion over the São Paulo Plateau presented a tendency of counter-clockwise circulation during the whole cruise period. [ABSTRACT FROM AUTHOR]

Two contrasting flow regimes exist in the stable boundary layer (SBL), as evidenced from both observational and modeling studies. In general, numerical schemes such as those used in numerical weather prediction and climate models (NWPCs) reproduce a transition between SBL regimes. However, the characteristics of such a transition depend on the turbulence parameterizations and stability functions used to represent the eddy diffusivity in the models. The main goal of the present study is to detail how the two SBL regimes occur in single-column models (SCMs) by analyzing the SBL structure and its dependence on external parameters. Two different turbulence closure orders (first order and an E-l model) and two types of stability functions (short and long tail) are considered. The control exerted by the geostrophic wind and the surface cooling rate on the model SBL regimes is addressed. The model flow presents a three-layer structure: a fully turbulent, weakly stable layer (WSL) next to the surface; a very stable layer (VSL) above that; and a laminar layer above the other two and toward the domain top. It is shown that theWSLand VSL are related to both SBL regimes, respectively. Furthermore, the numerically simulated SBL presents the two-layer structure regardless of the turbulence parameterization order and stability function used. The models also reproduce other features reported in recent observational studies: an S-shaped dependence of the thermal gradient on the mean wind speed and an independence of the vertical gradient of friction velocity du* on the mean wind speed. [ABSTRACT FROM AUTHOR]

The antimicrobial peptide LyeTxI isolated from the venom of the spider Lycosa erythrognatha is a potential model to develop new antibiotics against bacteria and fungi. In this work, we studied a peptide derived from LyeTxI, named LyeTxI-b, and characterized its structural profile and its in vitro and in vivo antimicrobial activities. Compared to LyeTxI, LyeTxI-b has an acetylated N-terminal and a deletion of a His residue, as structural modifications. The secondary structure of LyeTxI-b is a well-defined helical segment, from the second amino acid to the amidated C-terminal, with no clear partition between hydrophobic and hydrophilic faces. Moreover, LyeTxI-b shows a potent antimicrobial activity against Gram-positive and Gram-negative planktonic bacteria, being 10-fold more active than the native peptide against Escherichia coli. LyeTxI-b was also active in an in vivo model of septic arthritis, reducing the number of bacteria load, the migration of immune cells, the level of IL-1β cytokine and CXCL1 chemokine, as well as preventing cartilage damage. Our results show that LyeTxI-b is a potential therapeutic model for the development of new antibiotics against Gram-positive and Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Understanding the supramolecular environment of crystal structures is necessary to facilitate designing molecules with desirable properties. A series of 12 novel 1,3,5-tris(1-phenyl-1H-pyrazol-5-yl)benzenes was used to assess the existence of planar stacking columns in supramolecular structures of pyrazoles. This class of molecules with different substituents may assist in understanding how small structural changes affect the supramolecular environment. The obtained compounds did not present the formation of planar stacking interactions between benzenes in solid or liquid states. This supposition was indicated by single crystal diffraction, Density Functional Theory (DFT) and quantum theory of atoms in molecules (QTAIM) calculations, and concentration-dependent liquid-state H nuclear magnetic resonance (NMR). NMR showed that chemical shifts of benzene and pyrazole hydrogens confirm that planar stacking interactions are not formed in solution. The crystalline structures presented different molecular conformations. The molecular structures of 5 and 9b are in a twisted conformation, while compound 7 showed a conformation analogous to a calyx form. [ABSTRACT FROM AUTHOR]

The variation of the atmospheric temperature near the surface associated with anthropogenic effects is analyzed using a simplified atmospheric model. Local changes in cloud cover and four different scenarios of atmospheric concentration of carbon dioxide are considered. The results show that the highest temperature variability occurs in the weak wind and decoupled state and in the transition between flow regimes. In agreement with previous efforts, the results indicate that the reduction of diurnal temperature range is related to the existence of two distinct flow regimes in the stable boundary layer. However, in the decoupled state, the occurrence of intermittent bursts of turbulence may cause temperature variations among the different scenarios to become unpredictable. It implies that it is difficult to predict the diurnal temperature range in places where low winds are common. [ABSTRACT FROM AUTHOR]

Several products of industrial interest are produced by Bacillus, including enzymes, antibiotics, amino acids, insecticides, biosurfactants and bacteriocins. This study aimed to investigate the potential of two bacterial isolates (P5 and C3) from puba, a regional fermentation product from cassava, to produce multiple substances with antimicrobial and surface active properties. Phylogenetic analyses showed close relation of isolates P5 and C3 with Bacillus amyloliquefaciens and Bacillus thuringiensis, respectively. Notably, Bacillus sp. P5 showed antimicrobial activity against pathogens such as Listeria monocytogenes and Bacillus cereus, in addition to antifungal activity. The presence of genes encoding pre-subtilosin (sboA), malonyl CoA transacylase (ituD), and the putative transcriptional terminator of surfactin (sfp) were detected in Bacillus sp. P5, suggesting the production of the bacteriocin subtilosin A and the lipopeptides iturin A and surfactin by this strain. For Bacillus sp. C3 the presence of sboA and spas (subtilin) genes was observed by the first time in members of B. cereus cluster. Bacillus sp. P5 showed emulsifying capability on mineral oil, soybean biodiesel and toluene, while Bacillus sp. C3 showed emulsifying capability only on mineral oil. The reduction of the surface tension in culture medium was also observed for strain P5, confirming the production of surfaceactive compounds by this bacterium. Monoprotonated molecular species and adducts of sodium and potassium ions of surfactin, iturin, and fengycin were detected in the P5 culture medium. Comparative MS/MS spectra of the peak m/z 1030 (C14 surfactin A or C15 surfactin B [M+Na]+) and peak m/z 1079 (C15 iturin [M+Na]+) showed the same fragmentation profile of standards, confirming the molecular identification. In conclusion, Bacillus sp. P5 showed the best potential for the production of antifungal, antibacterial, and biosurfactant substances. [ABSTRACT FROM AUTHOR]

Background Exiguobacterium antarcticum strain B7 is a Gram-positive psychrotrophic bacterial species isolated in Antarctica. Although this bacteria has been poorly studied, its genome has already been sequenced. Therefore, it is an appropriate model for the study of thermal adaptation. In the present study, we analyzed the transcriptomes and proteomes of E. antarcticum B7 grown at 0°C and 37°C by SOLiD RNA-Seq, Ion Torrent RNA-Seq and two-dimensional difference gel electrophoresis tandem mass spectrometry (2D-DIGE-MS/MS). Results We found expression of 2,058 transcripts in all replicates from both platforms and differential expression of 564 genes (absolute log2FC ⩾1, P-value <0.001) comparing the two temperatures by RNA-Seq. A total of 73 spots were differentially expressed between the two temperatures on 2D-DIGE, 25 of which were identified by MS/MS. Some proteins exhibited patterns of dispersion in the gel that are characteristic of post-translational modifications. Conclusions Our findings suggest that the two sequencing platforms yielded similar results and that different omic approaches may be used to improve the understanding of gene expression. To adapt to low temperatures, E. antarcticum B7 expresses four of the six cold-shock proteins present in its genome. The cold-shock proteins were the most abundant in the bacterial proteome at 0°C. Some of the differentially expressed genes are required to preserve transcription and translation, while others encode proteins that contribute to the maintenance of the intracellular environment and appropriate protein folding. The results denote the complexity intrinsic to the adaptation of psychrotrophic organisms to cold environments and are based on two omic approaches. They also unveil the lifestyle of a bacterial species isolated in Antarctica. [ABSTRACT FROM AUTHOR]

Sedentary behavior (SB) expression and its underlying causal factors have been progressively studied, as it is a major determinant of decreased health quality. In the present study we applied Genotype x Age (GxAge) and Genotype x Sex (GxSex) interaction methods to determine if the phenotypic expression of different SB traits is influenced by an interaction between genetic architecture and both age and sex. A total of 1345 subjects, comprising 249 fathers, 327 mothers, 334 sons and 325 daughters, from 339 families of The Portuguese Healthy Family Study were included in the analysis. SB traits were assessed by means of a 3-d physical activity recall, the Baecke and IPAQ questionnaires. GxAge and GxSex interactions were analyzed using SOLAR 4.0 software. Sedentary behaviour heritability estimates were not always statistically significant (p>0.05) and ranged from 3% to 27%. The GxSex and GxAge interaction models were significantly better than the single polygenic models for TV (min/day), EEsed (kcal/day), personal computer (PC) usage and physical activty (PA) tertiles. The GxAge model is also significantly better than the polygenic model for Sed (min/day). For EEsed, PA tertiles, PC and Sed, the GxAge interaction was significant because the genetic correlation between SB environments was significantly different from 1. Further, PC and Sed variance heterogeneity among distinct ages were observed. The GxSex interaction was significant for EEsed due to genetic variance heterogeneity between genders and for PC due to a genetic correlation less than 1 across both sexes. Our results suggest that SB expression may be influenced by the interactions between genotype with both sex and age. Further, different sedentary behaviors seem to have distinct genetic architectures and are differentially affected by age and sex. [ABSTRACT FROM AUTHOR]

Moderate-to-high levels of physical activity are established as preventive factors in metabolic syndrome development. However, there is variability in the phenotypic expression of metabolic syndrome under distinct physical activity conditions. In the present study we applied a Genotype X Environment interaction method to examine the presence of GxEE interaction in the phenotypic expression of metabolic syndrome. A total of 958 subjects, from 294 families of The Portuguese Healthy Family study, were included in the analysis. Total daily energy expenditure was assessed using a 3 day physical activity diary. Six metabolic syndrome related traits, including waist circumference, systolic blood pressure, glucose, HDL cholesterol, total cholesterol and triglycerides, were measured and adjusted for age and sex. GxEE examination was performed on SOLAR 4.3.1. All metabolic syndrome indicators were significantly heritable. The GxEE interaction model fitted the data better than the polygenic model (p<0.001) for waist circumference, systolic blood pressure, glucose, total cholesterol and triglycerides. For waist circumference, glucose, total cholesterol and triglycerides, the significant GxEE interaction was due to rejection of the variance homogeneity hypothesis. For waist circumference and glucose, GxEE was also significant by the rejection of the genetic correlation hypothesis. The results showed that metabolic syndrome traits expression is significantly influenced by the interaction established between total daily energy expenditure and genotypes. Physical activity may be considered an environmental variable that promotes metabolic differences between individuals that are distinctively active. [ABSTRACT FROM AUTHOR]

An extraction procedure using Tris-HCl buffer solution was employed in order to extract water-soluble proteins from seed samples of oat, wheat and soybean. Initially, the total protein concentration was determined by the Bradford method in each solution, after the extraction procedure. The soybean sample showed a higher concentration of total protein compared to the others. The protein extracts obtained were separated by reverse-phase chromatography (RP-HPLC-UV). The protein fractions were collected and analyzed by graphite furnace atomic absorption spectrometry (GFAAS) and matrix-assisted laser desorption/ionization (MALDI-TOF-MS) for determination of Cu, Fe, Mn and Zn and identification of proteins, respectively. The combination of techniques such as RP-HPLC-UV, GFAAS and MALDI-TOF-MS allowed the identification of several proteins bound to metals present in the seed samples. [ABSTRACT FROM AUTHOR]

Abstract: The study presents an analysis of two-point correlations between time series of nocturnal atmospheric wind, obtained from two micrometeorological towers, 45 m horizontally apart, each equipped with two sonic anemometers, 2.5 m vertically apart. It focuses on the scale dependence of the two-point correlations obtained from sensors vertically and horizontally separated. In particular, the role of low-frequency non-turbulent processes in the correlations is assessed, and compared to that of the turbulent scales of motion. The vertical correlations of the streamwise and vertical wind components show little dependence on the turbulence intensity, but those of the spanwise component decrease appreciably as it gets more turbulent. Multiresolution decomposition shows that the two-point correlations become increasingly dominated by low-frequency scales as it gets less turbulent, and that such large-scale processes are largely reduced in fully turbulent conditions. It is also shown that the vertical correlations of the spanwise wind component is negative for very small time scales. Horizontal two-point correlations obtained at the 45 m separation distance between the towers are almost entirely dominated by low-frequency motions, regardless of the turbulence intensity, but the magnitude of such correlations decreases with increasing turbulence intensity for any wind components. A comparison between the horizontal two-point correlations and autocorrelations taken with a time lag given by the ratio of the horizontal separation to the mean wind component in the direction that connects the two towers leads to the conclusion that the statistical properties of turbulence are often preserved over the horizontal distance, despite the lack of turbulence correlations for that separation. [Copyright &y& Elsevier]

Abstract: An investigation of the ethanolic extract from stems of Caesalpinia echinata Lam (Leguminosae-Caesalpinioideae) led to the isolation of five new cassane diterpenes along with known lambertianic acid. Their structures were determined based on spectroscopic methods. A preliminary study on leishmanicidal activity demonstrated that compounds 1, 2 and 6 were found to inhibit the growth of amastigote-like forms of Leishmania amazonensis without affecting mononuclear cells obtained from human peripheral blood. [Copyright &y& Elsevier]