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Statistical relations used for estimating the dissipation rate of turbulent kinetic energy (TKE) in isotropic turbulence from the inertial subrange of Lagrangian temporal and spatial structure functions are extended here to the case of more realistic turbulence spectra that include low-frequency and low-wavenumber ranges. It is shown that using the traditional relations based only on the inertial subrange substantially underestimates the dissipation. The improved relations are better constrained by experimental data from which the dissipation is evaluated, enabling more accurate dissipation estimates. The concept is illustrated using laboratory data from water tank experiments of turbulence generated by an oscillating cylinder, where the dissipation is evaluated in three independent ways: from Lagrangian spectra and from Lagrangian temporal and spatial structure functions calculated from the motion of neutrally buoyant finite-sized particles. An additional correction to the relations for estimating the dissipation from the spatial structure functions is applied to take into account the filtering effect of the particles due to their finite size. It is found that, for these particular experiments, the TKE dissipation rate scales well with dimensionally consistent quantities built using the amplitude of the oscillation of the cylinder and the period of its motion, and the constant of proportionality in this scaling relation is determined using the method proposed here. Although the turbulence under consideration is quite anisotropic, the adopted theoretical framework, which assumes isotropic turbulence, seems to be applicable to the experimental data as long as the turbulence statistics are averaged over the three main flow directions. [ABSTRACT FROM AUTHOR]

Although it is known that trapped lee waves propagating at low levels in a stratified atmosphere exert a drag on the mountains that generate them, the distribution of the corresponding reaction force exerted on the atmospheric mean circulation, defined by the wave momentum flux profiles, has not been established, because for inviscid trapped lee waves these profiles oscillate indefinitely downstream. A framework is developed here for the unambiguous calculation of momentum flux profiles produced by trapped lee waves, which circumvents the difficulties plaguing the inviscid trapped lee wave theory. Using linear theory, and taking Scorer's two‐layer atmosphere as an example, the waves are assumed to be subject to a small dissipation, expressed as a Rayleigh damping. The resulting wave pattern decays downstream, so the momentum flux profile integrated over the area occupied by the waves converges to a well‐defined form. Remarkably, for weak dissipation, this form is independent of the value of Rayleigh damping coefficient, and the inviscid drag, determined in previous studies, is recovered as the momentum flux at the surface. The divergence of this momentum flux profile accounts for the areally integrated drag exerted by the waves on the atmosphere. The application of this framework to this and other types of trapped lee waves potentially enables the development of physically based parametrizations of the effects of trapped lee waves on the atmosphere. [ABSTRACT FROM AUTHOR]

Finite-sized neutrally buoyant particles suspended in a turbulent flow do not typically follow the fluid motion, whereas sufficiently small neutrally buoyant particles, known as tracers, do. Turbulence properties probed by the two types of particles, thus, differ primarily due to spatial filtering, whereby scales of motion in the energy spectrum smaller than the particle diameter D are suppressed, whereas those larger are retained. In this study, this filtering effect is quantified for flows with Reynolds numbers in the range R e λ ≈ 32 – 2000 using a model of isotropic and homogeneous turbulence based on analytical wavenumber and Lagrangian frequency energy spectra. The coefficients scaling these spectra are estimated by comparing the dissipation rate, amplitude of the frequency spectrum, and acceleration variance for the fluid motion, as well as the acceleration and velocity variances of the particle motion, with laboratory experiments and numerical simulations. The model reproduces scalings for the acceleration variances of both the fluid and the particles at high Reynolds number. The model is then used to predict the ratios of the velocity variance, acceleration variance, and the dissipation rate obtained from the particles to those of the flow. These ratios depart from 1 as D increases (as expected), but the fluid velocity variance is much less severely underestimated by the particle motion than the acceleration variance and dissipation rate, for a given D and R e λ . These results allow delimiting more systematically the conditions under which finite-sized neutrally buoyant particles could be as useful to probe turbulent flows as tracer particles in laboratory experiments. [ABSTRACT FROM AUTHOR]

• Surface tension for 3 mixtures of trifluoro ethanol with hydrogenated alcohols is reported. • All 3 mixtures display aneotropy, i.e. minima in the surface tension vs composition curve. • Phase equilibria, bulk properties and interfacial properties were modeled with soft-SAFT-DGT. • soft-SAFT-DGT predictions are in excellent agreement with the experimental data. • This is the first reported example of aneotropy in mixtures of hydrogen-bonded components. New experimental data is reported for the surface tension of mixtures of 2,2,2-trifluoroethanol with three hydrogenated alcohols, namely ethanol, 1-propanol and 1-butanol, at 293.2 K along the full composition range. The phase equilibria, bulk properties of the mixtures and interfacial properties were modeled with soft-SAFT combined with the density gradient theory. Excellent agreement was found between predictions from the theory and the experimental results, the model allowing interpreting the interfacial behaviour of the mixtures, providing a microscopic explanation of the unusual interfacial behavior of these particular mixtures. Negative aneotropy (minima in the surface tension vs composition curve) is observed for the three mixtures. Negative aneotropy is a rare and poorly understood phenomenon usually associated to weak intermolecular interactions between the components of the mixture, which is not the case in these systems as the components interact strongly through hydrogen bonding. To the best of our knowledge, this is the first reported example of this type of negative aneotropy. [ABSTRACT FROM AUTHOR]

A series of 8 laboratory experiments was used to investigate the dynamics of a few almost neutrally-buoyant finite-size particles in the entire volume of a rectangular tank open to air and filled with water. Stirring was achieved by a cylinder executing a two-dimensional periodic Lissajoux figure. The rate and direction of stirring by the cylinder was varied. The particle motions were analysed using a tracking method developed for the experimental design. The Reynolds number associated with the large-scale stirring motion was in a turbulent range of [5,693–11,649] across all experiments. The absence of stirring in the direction of the cylinder axis, the constant interference of the cylinder with the eddies and the presence of walls and the free-surface resulted in a flow that was both inhomogeneous and anisotropic as recorded by the particle motion. Despite these unusual conditions, the single-particle dispersion across all experiments could be seen to follow a ballistic regime until about two-fifths of the particle Lagrangian velocity auto-correlation time T L. It was followed by a brief diffusive regime between T L and 2.5T L , after which the presence of the boundaries prevented further dispersion. Such evolution is consistent with classic predictions for fluid tracer dispersion in homogeneous and isotropic turbulence. Particle-pair dispersion was more complex. Both the fixed time-averaged and length-scale-dependent particle-pair dispersion rates averaged across pairs showed the ballistic dispersion regime, whereas the subsequent diffusive regime was better borne out by the length-scale-dependent particle-pair dispersion. A super-diffusive Richardson regime was not unmistakably detected. Substantial variability was however found across the different pairs of particles, which was linked to differences in the decorrelation time of the velocity difference as a result of the inhomogeneity of the turbulence. For short initial separations, some particle pairs had a better separation of the time scales delimiting the ballistic and diffusive regimes and showed hints of a brief Richardson regime. • Finite-size particles in 3D anisotropic and inhomogeneous turbulence. • 3D particle tracking developed for the experimental design. • Limited impact of the particles on the velocity statistics. • Ballistic and diffusive particle dispersion regimes found. • Elusive super-diffusive particle-pair dispersion regime linked to turbulence inhomogeneity. [ABSTRACT FROM AUTHOR]

The parameterization of orographic gravity wave drag (OGWD) in the Weather Research and Forecasting model is extended by including the second‐order Wentzel–Kramers–Brillouin (WKB) corrections to the surface wave momentum flux (SWMF) caused by wind profile shear (WSHR) and curvature (WCUR) effects. Simulations of the atmospheric circulation are performed to study the behaviour and impact of the WKB corrections. In January, the SWMF is weakened in the Northern Hemisphere (NH) midlatitudes by the WSHR term, while the WCUR acts to enhance the SWMF over Antarctica. In July, the WSHR corrections are similar to those in January, whereas the WCUR term produces corrections of opposite sign in the high latitudes of each hemisphere. The latter is attributed to the increase of near‐surface winds in the cold season which reverses the low‐level wind profile curvature. The seasonal reversal of the WCUR term contradicts previous findings obtained from offline evaluation using reanalysis datasets. This may be due to the different OGWD parameterization schemes used, or it may suggest a sensitivity to the height at which the wind profile effects are evaluated. Changes in the SWMF can affect the vertical distribution of parameterized OGWD. In January, the OGWD in the NH midlatitudes is decreased in the lower troposphere but increased in the upper troposphere. This is because a reduced SWMF inhibits wave breaking in the lower troposphere. Therefore, more wave momentum flux (WMF) is transported to the upper troposphere which enhances wave breaking there. The increased upper‐tropospheric wave breaking in turn decreases the WMF propagating into the stratosphere where the OGWD is reduced. In July, the reduction of SWMF over Antarctica is more notable than in the NH midlatitudes in January. Consequently, the OGWD is weakened in the upper troposphere over Antarctica. [ABSTRACT FROM AUTHOR]

Flavodiiron proteins (FDPs) are a family of enzymes with a significant role in O2/H2O2 and/or NO detoxification through the reduction of these species to H2O or N2O, respectively. All FDPs contain a minimal catalytic unit of two identical subunits, each one having a metallo‐β‐lactamase‐like domain harboring the catalytic diiron site, and a flavodoxin‐like domain. However, more complex and diverse arrangements in terms of domains are found in this family, of which the class H enzymes are among the most complex. One of such FDPs is encoded in the genome of the anaerobic bacterium Syntrophomonas wolfei subsp. wolfei str. Goettingen G311. Besides the core domains, this protein is predicted to have three additional ones after the flavodoxin core domain: two short‐chain rubredoxins and a NAD(P)H:rubredoxin oxidoreductase‐like domain. This enzyme, FDP_H, was produced and characterized and the presence of the predicted cofactors was investigated by a set of biochemical and spectroscopic methodologies. Syntrophomonas wolfei FDP_H exhibited a remarkable O2 reduction activity with a kcat = 52.0 ± 1.2 s−1 and a negligible NO reduction activity (~ 100 times lower than with O2), with NADH as an electron donor, that is, it is an oxygen‐selective FDP. In addition, this enzyme showed the highest turnover value for H2O2 reduction (kcat = 19.1 ± 2.2 s−1) ever observed among FDPs. Kinetic studies of site‐directed mutants of iron‐binding cysteines at the two rubredoxin domains demonstrated the essential role of these centers since their absence leads to a significant decrease or even abolishment of O2 and H2O2 reduction activities. [ABSTRACT FROM AUTHOR]

The effects of vertical wind shear on orographic gravity wave drag derived previously from inviscid linear theory are evaluated using reanalysis data. Emphasis is placed on the relative importance of uniform and directional shear (associated with first and second vertical derivatives of the wind velocity), which are theoretically predicted, respectively, to reduce and enhance the surface drag. Two levels at which the wind derivatives are estimated are considered for evaluating the shear corrections to the drag: a height just above the parametrized boundary‐layer height (BLH) in the ECMWF model, and a height of order the standard deviation of the subgrid‐scale orography elevation (SDH), adopted by previous authors. A climatology of the Richardson number (Ri) computed for the decade 2006–2015 suggests that the Antarctic region has a high incidence of low Ri values, implying high shear conditions. Shear estimated at the BLH has a relatively modest impact on the drag, whereas shear estimated at the SDH has a stronger impact. Predicted drag enhancement is more widespread than drag reduction because terms involving second wind derivatives dominate the drag correction for a larger fraction of the time than terms involving first derivatives. A comparison of climatologies of the drag corrections for horizontally elliptical mountains (which represent anisotropic subgrid‐scale orography in parametrizations) and axisymmetric mountains always results in drag enhancement over Antarctica, with a maximum during the JJA season, showing qualitative robustness to both calculation height and orography anisotropy. However, this enhancement is smaller when using elliptical instead of axisymmetric orography. This is because the shear vector is predominantly oriented along mountain ridges rather than across them when the orography is anisotropic. Inverse of the Richardson number Ri−1 averaged seasonally using daily data over the decade 2006–2015 at the boundary‐layer height for (a) DJF, (b) JJA. [ABSTRACT FROM AUTHOR]

A simple analytical model is developed for the current induced by the wind and modified by surface wind waves in the oceanic surface layer, based on a first-order turbulence closure and including the effect of a vortex force representing the Stokes drift of the waves. The shear stress is partitioned between a component due to shear in the current, which is reduced at low turbulent Langmuir number Lat, and a wave-induced component, which decays over a depth proportional to the dominant wavelength λw. The model reproduces the apparent reduction of the friction velocity and enhancement of the roughness length estimated from current profiles, detected in a number of studies. These effects are predicted to intensify as Lat decreases and are entirely attributed to nonbreaking surface waves. The current profile becomes flatter for low Lat owing to a smaller fraction of the total shear stress being supported by the current shear. Comparisons with the comprehensive dataset provided by the laboratory experiments of Cheung and Street show encouraging agreement, with the current speed normalized by the friction velocity decreasing as Lat decreases and λw increases if the model is adjusted to reflect the effects of a full wave spectrum on the intensity and depth of penetration of the wave-induced stress. A version of the model where the shear stress decreases to zero over a depth consistent with the measurements accurately predicts the surface current speed. These results contribute toward developing physically based momentum flux parameterizations for the wave-affected boundary layer in ocean circulation models. [ABSTRACT FROM AUTHOR]

Resonance Raman spectra of Fe-S proteins are sensitive to the cluster type, structure and symmetry. Furthermore, bands that originate from bridging and terminal Fe-S vibrations in the 2Fe-2S, 3Fe-4S and 4Fe-4S clusters can be sensitively distinguished in the spectra, as well as the type of non-cysteinyl coordinating ligands, if present. For these reasons, resonance Raman spectroscopy has been playing an exceptionally active role in the studies of Fe-S proteins of diverse structures and functions. We provide here a concise overview of the structural information that can be obtained from resonance Raman spectroscopy on Fe-S clusters, and in parallel, refer to their thermodynamic properties (e.g., reduction potential), which together define the physiological roles of Fe-S proteins. We demonstrate how the knowledge gained over the past several decades on simple clusters nowadays enables studies of complex structures that include Fe-S clusters coupled to other centers and transient processes that involve cluster inter-conversion, biogenesis, disassembly and catalysis. [ABSTRACT FROM AUTHOR]

Mountain waves excited by narrow 3D orography are investigated using idealized numerical simulations of atmospheric flows with directional wind shear. The stability of these waves is compared with the stability of hydrostatic mountain waves. The focus is on understanding how wave breaking is modified via gravity wave-critical level interaction, when non-hydrostatic (dispersive) effects arise. The influence of non-hydrostatic effects on wave breaking appears to be a function of the intensity of the background shear, increasing the stability of the flow (inhibiting wave breaking) for weak wind shear, but decreasing it instead (enhancing wave breaking) for stronger wind shear. [ABSTRACT FROM AUTHOR]

A method is proposed for estimating the surface-layer depth $$(z_s)$$ and the friction velocity $$(u_*)$$ as a function of stability (here quantified by the Obukhov length, L) over the complete range of unstable flow regimes. This method extends that developed previously for stable conditions by Argaín et al. (Boundary-Layer Meteorol 130:15-28, 2009), but uses a qualitatively different approach. The method is specifically used to calculate the fractional speed-up $$(\varDelta S)$$ in flow over a ridge, although it is suitable for more general boundary-layer applications. The behaviour of $$z_s \left( L\right) $$ and $$u_*\left( L\right) $$ as a function of L is indirectly assessed via calculation of $$\varDelta S\left( L\right) $$ using the linear model of Hunt et al. (Q J R Meteorol Soc 29:16-26, 1988) and its comparison with the field measurements reported in Coppin et al. (Boundary-Layer Meteorol 69:173-199, 1994) and with numerical simulations carried out using a non-linear numerical model, FLEX. The behaviour of $$\varDelta S$$ estimated from the linear model is clearly improved when $$u_*$$ is calculated using the method proposed here, confirming the importance of accounting for the dependences of $$z_s\left( L \right) $$ and $$u_*\left( L \right) $$ on L to better represent processes in the unstable boundary layer. [ABSTRACT FROM AUTHOR]

In this study, the Henry's law methodology is applied to predict the release of odorants present in single and multicomponent fragrance mixtures diluted in mineral oil, a simplified matrix used in cosmetic products. To attain this goal, the experimental Henry's law constant (H) of each odorant in each studied fragrance system (containing one, two, three, or four odorants) was first evaluated by plotting their liquid phase and experimental vapor phase concentrations assessed by headspace gas chromatography. From that point, the H value of each odorant in the multicomponent fragrance system was predicted from its corresponding Hexp in the single fragrance component system. The theoretical vapor-phase concentrations were also calculated using the activity coefficients for vapor-liquid equilibria by applying the thermodynamic UNIFAC model. The odor intensity and character of the studied fragrance systems were assessed through the Stevens's power law and Strongest Component models (psychophysical models). This study confirmed that the headspace concentrations and odor intensity of each odorant present in a multicomponent fragrance mixture dissolved in mineral oil can be efficiently predicted from its corresponding H determined when present alone in the simplified matrix, for low concentrations. Also, comparing both methodologies, UNIFAC and Henry's law, it was concluded that Henry's law is a better predictive model for the vapor-liquid equilibria, showing lower deviations from the experimental data. Therefore, the proposed predictive mathematical model can be attractive for the assessment of sensory quality of multicomponent fragrance systems in early formulation stages. [ABSTRACT FROM AUTHOR]

Linear nonhydrostatic theory is used to evaluate the drag produced by 3D trapped lee waves forced by an axisymmetric hill at a density interface. These waves occur at atmospheric temperature inversions, for example, at the top of the boundary layer, and contribute to low-level drag possibly misrepresented as turbulent form drag in large-scale numerical models. Unlike in 2D waves, the drag has contributions from a continuous range of wavenumbers forced by the topography, because the waves can vary their angle of incidence to match the resonance condition. This leads to nonzero drag for Froude numbers (Fr) both <1 and >1 and a drag maximum typically for Fr slightly below 1, with lower magnitude than in hydrostatic conditions owing to wave dispersion. These features are in good agreement with laboratory experiments using two axisymmetric obstacles, particularly for the lower obstacle, if the effects of a rigid lid above the upper layer and friction are taken into account. Quantitative agreement is less satisfactory for the higher obstacle, as flow nonlinearity increases. However, even in that case the model still largely outperforms both 3D hydrostatic and 2D nonhydrostatic theories, emphasizing the importance of both 3D and nonhydrostatic effects. The associated wave signatures are dominated by transverse waves for Fr lower than at the drag maximum, a dispersive 'Kelvin ship-wave' pattern near the maximum, and divergent waves for Fr beyond the maximum. The minimum elevation at the density-interface depression existing immediately downstream of the obstacle is significantly correlated with the drag magnitude. [ABSTRACT FROM AUTHOR]

Recent studies have become increasingly focused on the assessment of pharmaceuticals occurrence in aquatic ecosystems, however the potential toxicity to non-target organisms is still largely unknown. The antihistamine cetirizine is a commonly used pharmaceutical, already detected in surface waters of marine aquatic systems worldwide. In the present study Mytilus galloprovincialis mussels were exposed to a range of cetirizine concentrations (0.3, 3.0, 6.0 and 12.0 μg/L), resembling moderate to highly contaminated areas, over 28 days. The responses of different biochemical markers were evaluated in mussels whole soft tissue, and included energy-related parameters (glycogen content, GLY; protein content, PROT; electron transport system activity, ETS), and oxidative stress markers (superoxide dismutase activity, SOD; catalase activity, CAT; glutathione S-transferases activity, GSTs; lipid peroxidation levels, LPO; reduced (GSH) and oxidized (GSSG) glutathione content). The results obtained demonstrated that with the increase of exposure concentrations mussels tended to increase their energy reserves and maintain their metabolic potential, which was significantly higher only at the highest concentration. Our findings clearly revealed that cetirizine inhibited the activity of GSTs and although induced the activity of antioxidant enzymes (SOD and CAT) mussels were not able to prevent cellular damages observed through the increase of LPO associated to the increase of exposure concentrations. Thus, this study confirmed that cetirizine induces toxic effects in Mytilus galloprovincialis , which, considering their trophic relevance, wide use as bioindicator and wide spatial distribution of this species, can result in ecological and economic negative impacts at a large scale. [ABSTRACT FROM AUTHOR]

A linear model is used to diagnose the onset of rotors in flow over 2D hills, for atmospheres that are neutrally stratified near the surface and stably stratified aloft, with a sharp temperature inversion in between, where trapped lee waves may propagate. This is achieved by coupling an inviscid two-layer mountain-wave model and a bulk boundary-layer model. The full model shows some ability to diagnose flow stagnation associated with rotors as a function of key input parameters, such as the Froude number and the height of the inversion, in numerical simulations and laboratory experiments carried out by previous authors. While calculations including only the effects of mean flow attenuation and velocity perturbation amplification within the surface layer represent flow stagnation fairly well in the more non-hydrostatic cases, only the full model, taking into account the feedback of the surface layer on the inviscid flow, satisfactorily predicts flow stagnation in the most hydrostatic case, although the corresponding condition is unable to discriminate between rotors and hydraulic jumps. Versions of the model not including this feedback severely underestimate the amplitude of trapped lee waves in that case, where the Fourier transform of the hill has zeros, showing that those waves are not forced directly by the orography. [ABSTRACT FROM AUTHOR]

Mountain wave breaking, and the resulting potential for the generation of turbulence in the atmosphere, are investigated using numerical simulations of idealized, nearly hydrostatic, atmospheric flows with directional wind shear over an axisymmetric isolated mountain. These simulations, which use the WRF-ARW model, differ in degree of flow nonlinearity and shear intensity, quantified through the dimensionless mountain height and the Richardson number of the incoming flow, respectively. The aim is to diagnose wave breaking based on large-scale flow variables. The simulation results have been used to produce a regime diagram giving a description of the wave breaking behaviour in Richardson number-dimensionless mountain height parameter space. By selecting flow overturning occurrence as a discriminating factor, it was possible to split the regime diagram into sub-regions with and without wave breaking. When mountain waves break, the associated convective instability leads to turbulence generation (which is one of the known forms of clear air turbulence (CAT)). Thus, regions within the simulation domain where wave breaking and the development of CAT are expected have been identified. The extent of these regions increases with terrain elevation and background wind shear intensity. Analysis of the model output, supported by theoretical arguments, suggests the existence of a link between wave breaking and the relative orientations of the incoming wind vector and the horizontal velocity perturbation vector. More specifically, in a wave breaking event, due to the effect of critical levels, the background wind vector and the wavenumber vector of the dominant mountain waves are perpendicular. It is shown that, at least for the wind profile employed in the present study, this corresponds to a situation where the background wind vector and the velocity perturbation vector are also approximately perpendicular. [ABSTRACT FROM AUTHOR]

Among crucial pathogenesis-related features in I Candida i species, this special issue addresses the central role of Hsp90 across the fungal kingdom and the unique nature of nonstandard translation in I C. albicans i . Most yeast infections in humans are attributable to I Candida i species, particularly I Candida albicans i , but several other species have seen an increase in incidence as human pathogens, including I C. glabrata i , I C. parapsilosis i , and I Cryptococcus neoformans i . Some, but not all, resistance mechanisms and adaptive responses are conserved between these pathogenic and nonpathogenic fungi, highlighting the limitations of basing antifungal response paradigms on data from nonpathogenic model systems. [Extracted from the article]

The current study assessed the biochemical alterations induced in the clam species Ruditapes philippinarum after exposure to salinity shifts (14, 28 and 42) and arsenic (As) contamination (0 and 2 mg/L). The capacity of this species to recover (96 h and 28 days) after exposure (96 h) to both stressors, acting alone and in combination, was also evaluated. After exposure, regardless of the salinity tested, clams contaminated with As showed higher concentrations than non-contaminated specimens. After recovery, As concentration in clams decreased, with contaminated and non-contaminated specimens presenting similar values. The results obtained further demonstrated that exposure to As (2 mg/L) at different salinities (salinities 14, 28 and 42) and salinity 42 (As 0 mg/L) lead to an increase of lipid peroxidation and detoxification mechanisms in clams, compared with non-contaminated clams at salinities of 14 and 28. After recovery, at salinities 14 and 28, clams previously exposed to As were capable to decrease their oxidative stress to levels found in non-contaminated clams. Nevertheless, at salinity 42 both contaminated and non-contaminated clams did not survive. Overall results of measured energy-related parameters, indicators of oxidative stress, antioxidant and biotransformation enzymes indicated that As exposure and salinity shifts caused biochemical alterations in R. philippinarum , with stronger impacts when both stressors were acting in combination. [ABSTRACT FROM AUTHOR]

Aerobic respiratory chains from all life kingdoms are composed by several complexes that have been deeply characterized in their isolated form. These membranous complexes link the oxidation of reducing substrates to the reduction of molecular oxygen, in a process that conserves energy by ion translocation between both sides of the mitochondrial or prokaryotic cytoplasmatic membranes. In recent years there has been increasing evidence that those complexes are organized as supramolecular structures, the so-called supercomplexes and respirasomes, being available for eukaryotes strong data namely obtained by electron microscopy and single particle analysis. A parallel study has been developed for prokaryotes, based on blue native gels and mass spectrometry analysis, showing that in these more simple unicellular organisms such supercomplexes also exist, involving not only typical aerobic-respiration associated complexes, but also anaerobic-linked enzymes. After a short overview of the data on eukaryotic supercomplexes, we will analyse comprehensively the different types of prokaryotic aerobic respiratory supercomplexes that have been thus far suggested, in both bacteria and archaea. This article is part of a Special Issue entitled Organization and dynamics of bioenergetic systems in bacteria, edited by Prof Conrad Mullineaux. [ABSTRACT FROM AUTHOR]

The presence of toxic compounds derived from biomass pre-treatment in fermentation media represents an important drawback in second-generation bio-ethanol production technology and overcoming this inhibitory effect is one of the fundamental challenges to its industrial production. The aim of this study was to systematically identify, in industrial medium and at a genomic scale, the Saccharomyces cerevisiae genes required for simultaneous and maximal tolerance to key inhibitors of lignocellulosic fermentations. Based on the screening of EUROSCARF haploid mutant collection, 242 and 216 determinants of tolerance to inhibitory compounds present in industrial wheat straw hydrolysate (WSH) and in inhibitor-supplemented synthetic hydrolysate were identified, respectively. Genes associated to vitamin metabolism, mitochondrial and peroxisomal functions, ribosome biogenesis and microtubule biogenesis and dynamics are among the newly found determinants of WSH resistance. Moreover, PRS3, VMA8, ERG2, RAV1 and RPB4 were confirmed as key genes on yeast tolerance and fermentation of industrial WSH. [ABSTRACT FROM AUTHOR]

Composite carbon molecular sieve membranes (c-CMSM) were prepared in a single dipping-drying-carbonization step from phenolic resin solutions (12.5-15 wt.%) loaded with boehmite nanoparticles (0.5-1.2 wt.%). A carbon matrix with well-dispersed Al2O3 nanowires was formed from the decomposition of the resin and dehydroxylation of boehmite. The effect of the carbon/Al2O3 ratio on the porous structure of the c-CMSM was accessed based on the pore size distribution and gas permeation toward N2, O2, CO2, He, H2, C3H6 and C3H8. c-CMSM with higher carbon/Al2O3 ratios had a more open porous structure, exhibiting higher permeabilities and lower permselectivities. c-CMSM performance was above the upper bound curves for polymeric membranes for several gas pairs, particularly for C3H6/C3H8 (permeability toward C3H6 of 420 barrer and permselectivity of 18.1 for a c-CMSM with carbon/Al2O3 ratio of 4.4). Unsupported films were also prepared (carbon/Al2O3 ratio 7.3) and crushed into small flakes. Equilibrium isotherms of H2, N2, O2, CO2, C3H3 and C3H6 at 293 K were determined on these flakes to obtain the kinetic and adsorption selectivities toward gas pairs of interest; obtained adsorption and diffusion coefficients accurately predicted the permeabilities of all studied gases except CO2 (experimental and predicted permeabilities of 1148 and 154 barrer, respectively). [ABSTRACT FROM AUTHOR]

Abstract: Semi-analytical expressions for the momentum flux associated with orographic internal gravity waves, and closed analytical expressions for its divergence, are derived for inviscid, stationary, hydrostatic, directionally-sheared flow over mountains with an elliptical horizontal cross-section. These calculations, obtained using linear theory conjugated with a third-order WKB approximation, are valid for relatively slowly-varying, but otherwise generic wind profiles, and given in a form that is straightforward to implement in drag parametrization schemes. When normalized by the surface drag in the absence of shear, a quantity that is calculated routinely in existing drag parametrizations, the momentum flux becomes independent of the detailed shape of the orography. Unlike linear theory in the limit, the present calculations account for shear-induced amplification or reduction of the surface drag, and partial absorption of the wave momentum flux at critical levels. Profiles of the normalized momentum fluxes obtained using this model and a linear numerical model without the WKB approximation are evaluated and compared for two idealized wind profiles with directional shear, for different Richardson numbers ( ). Agreement is found to be excellent for the first wind profile (where one of the wind components varies linearly) down to , while not so satisfactory, but still showing a large improvement relative to the limit, for the second wind profile (where the wind turns with height at a constant rate keeping a constant magnitude). These results are complementary, in the parameter range, to Broad’s generalization of the Eliassen–Palm theorem to 3D flow. They should contribute to improve drag parametrizations used in global weather and climate prediction models. [Copyright &y& Elsevier]

Productdesign and engineering is one of the novel paradigms ofthe 21st century, aiming for the development of novel added-valueproducts for consumers. Its application to the fragrance businessfor the purpose of enhancing the design and performance of perfumedproducts is of prime interest because nowadays three-fourths of consumergoods contain fragrances in their composition. Furthermore, fragrancedesign and classification is still performed on a trial-and-errorbasis which consequently increases products’ time to marketand consumption of raw materials. The Perfumery Radar methodologywas developed in the recent past as a tool for fragrance design andclassification with predictive capabilities. In this study, we extendit to the Perfumery Radar 2.0, which uses typical olfactory familiesused by the industry but also introduces outer and inner layers fora detailed description of the odor space of fine fragrances. Furthermore,we fully validated this methodology with sensorial classificationsof perfumers using several formulated fragrances with known compositionsand physicochemical properties with very good predictive accuracy.Finally, and for the first time, we applied the Perfumery Radar 2.0to 36 commercial fragrances differing in gender (feminine, masculine,and unisex) and covering the odor space. Correlations between olfactoryfamilies or odor descriptors with gender trends as well as with richerolfactory families such as chypre and fougère were also derived. [ABSTRACT FROM AUTHOR]

The drag produced by 2D orographic gravity waves trapped at a temperature inversion and waves propagating in the stably stratified layer existing above are explicitly calculated using linear theory, for a two-layer atmosphere with neutral static stability near the surface, mimicking a well-mixed boundary layer. For realistic values of the flow parameters, trapped-lee-wave drag, which is given by a closed analytical expression, is comparable to propagating-wave drag, especially in moderately to strongly nonhydrostatic conditions. In resonant flow, both drag components substantially exceed the single-layer hydrostatic drag estimate used in most parameterization schemes. Both drag components are optimally amplified for a relatively low-level inversion and Froude numbers Fr ≈ 1. While propagating-wave drag is maximized for approximately hydrostatic flow, trapped-lee-wave drag is maximized for l2 a = O(1) (where l2 is the Scorer parameter in the stable layer and a is the mountain width). This roughly happens when the horizontal scale of trapped lee waves matches that of the mountain slope. The drag behavior as a function of Fr for l2 H = 0.5 (where H is the inversion height) and different values of l2 a shows good agreement with numerical simulations. Regions of parameter space with high trapped-lee-wave drag correlate reasonably well with those where lee-wave rotors were found to occur in previous nonlinear numerical simulations including frictional effects. This suggests that trapped-lee-wave drag, besides giving a relevant contribution to low-level drag exerted on the atmosphere, may also be useful to diagnose lee-rotor formation. [ABSTRACT FROM AUTHOR]

Dear Editor, Pruritus, defined as an unpleasant sensation of the skin leading to the desire to scratch,1 is classically described as the most common skin symptom. As a technique common to all interventions, hypnosis was used to condition the sensation/perception of the pruritus. 6 Rucklidge JJ, Saunders D. The efficacy of hypnosis in the treatment of pruritus in people with HIV/AIDS: a time-series analysis. [Extracted from the article]

Summary: Gradual changes in the sensory environment can lead to abrupt changes in brain computations and perception. However, mechanistic understanding of the mediating microcircuits is missing. By sliding through light levels from starlight to daylight, we identify retinal ganglion cell types in the mouse that abruptly and reversibly switch the weighting of center and surround interactions in their receptive field around cone threshold. Two-photon-targeted recordings and genetic and viral tracing experiments revealed that the circuit element responsible for the switch is a large inhibitory neuron that provides direct inhibition to ganglion cells. Our experiments suggest that weak excitatory input via electrical synapses together with the spiking threshold in inhibitory cells act as a switch. We also reveal a switch-like component in the spatial integration properties of human vision at cone threshold. This work demonstrates that circuits in the retina can quickly and reversibly switch between two distinct states, implementing distinct perceptual regimes at different light levels. Video Abstract: Display Omitted [Copyright &y& Elsevier]

In this work a previous model developed to account forthe odorintensity of liquid perfumes was validated using sensory evaluationsperformed by two different panels, one of professional perfumers andanother of nontrained individuals (consumers). For that purpose, severalfragrance mixtures containing three perfumery raw materials (havingdifferent physicochemical properties) and a solvent were formulatedattending to the expertise of experienced perfumers. These mixtureswere then placed on textiles, allowed to evaporate, and then weresubjected to experimental olfactory evaluations, being their perceivedintensity rated by perfumers and nontrained panelists. The perceivedodor intensity of these samples was also predicted using our modelthat considers fragrance release and intensity perception. The resultsobtained show a good correlation with the ratings from both perfumersand nontrained panelists. In this way, it was shown that odor intensitycan be predicted using a structured model which accounts for the evaporationand olfactory perception of fragrances. [ABSTRACT FROM AUTHOR]

Phenolic resins loaded with two different inorganic fillers (boehmite (γ-A10(OH)) and silver (Ag)) were used to prepare composite carbon membranes. Polymer solutions containing γ-A10(OH) and AgNO3 were prepared and the effect of Ag on the transport properties of the composite membrane was evaluated. The polymer solutions were coated on α-Al203 tubes and carbonized in a single dipping-drying-pyrolysis step. After pyrolysis at 550°C, γ-AlO(OH) yielded γ-Al2O3, and Ag agglomerated forming spherical nanoparticles of 30 nm in diameter. Ag loading enhanced the carbon membrane performance for several gas pairs of interest, especially for C3H6/C3H8 separation, where the C3H6/C3H8 permselectivity increased from a maximum of 15 to 38. [ABSTRACT FROM AUTHOR]

Abstract: Alternative complexes III (ACIII) are recently identified membrane-bound enzymes that replace functionally the cytochrome bc 1/ b 6 f complexes. In general, ACIII are composed of four transmembrane proteins and three peripheral subunits that contain iron–sulfur centers and C-type hemes. ACIII are built by a combination of modules present in different enzyme families, namely the complex iron–sulfur molybdenum containing enzymes. In this article a historical perspective on the investigation of ACIII is presented, followed by an overview of the present knowledge on these enzymes. Electron transfer pathways within the protein are discussed taking into account possible different locations (cytoplasmatic or periplasmatic) of the iron–sulfur containing protein and their contribution to energy conservation. In this way several hypotheses for energy conservation modes are raised including linear and bifurcating electron transfer pathways. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012). [Copyright &y& Elsevier]

Background: The understanding of the molecular basis of yeast tolerance to ethanol may guide the design of rational strategies to increase process performance in industrial alcoholic fermentations. A set of 21 genes encoding multidrug transporters from the ATP-Binding Cassette (ABC) Superfamily and Major Facilitator Superfamily (MFS) in S. cerevisiae were scrutinized for a role in ethanol stress resistance. Results: A yeast multidrug resistance ABC transporter encoded by the PDR18 gene, proposed to play a role in the incorporation of ergosterol in the yeast plasma membrane, was found to confer resistance to growth inhibitory concentrations of ethanol. PDR18 expression was seen to contribute to decreased 3 H-ethanol intracellular concentrations and decreased plasma membrane permeabilization of yeast cells challenged with inhibitory ethanol concentrations. Given the increased tolerance to ethanol of cells expressing PDR18, the final concentration of ethanol produced during high gravity alcoholic fermentation by yeast cells devoid of PDR18 was lower than the final ethanol concentration produced by the corresponding parental strain. Moreover, an engineered yeast strain in which the PDR18 promoter was replaced in the genome by the stronger PDR5 promoter, leading to increased PDR18 mRNA levels during alcoholic fermentation, was able to attain a 6 % higher ethanol concentration and a 17 % higher ethanol production yield than the parental strain. The improved fermentative performance of yeast cells over-expressing PDR18 was found to correlate with their increased ethanol tolerance and ability to restrain plasma membrane permeabilization induced throughout high gravity fermentation. Conclusions: PDR18 gene over-expression increases yeast ethanol tolerance and fermentation performance leading to the production of highly inhibitory concentrations of ethanol. PDR18 overexpression in industrial yeast strains appears to be a promising approach to improve alcoholic fermentation performance for sustainable bio-ethanol production. [ABSTRACT FROM AUTHOR]

ABSTRACT A linear regression between odour detection thresholds and three basic physical properties (vapour pressure, water solubility and octanol/water partition coefficient) has been derived. The principles underlying this model are the transport process of the odorants from air to the olfactory neurons in the nasal epithelium. The regression was applied to odour detection thresholds measured from different authors separately, showing similar parameters. A general linear regression was obtained for odour detection threshold data from several authors and 121 chemicals. This regression allows a preliminary estimation of odour detection thresholds from literature data with fair accuracy. The coefficient of determination obtained, r2 = 0.769, indicates that these physical properties account for 77% of the odour threshold variance. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Composite carbon molecular sieve membranes (c-CMSM) were prepared from phenolic resin loaded with boehmite by a single dipping–drying–pyrolysis step. The composite membrane was analyzed by scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, mercury porosimetry, CO2 adsorption and permeation experiments. It was produced a 2μm thick composite uniform layer on top of a α-Al2O3 support. The composite top layer exhibited nanowires of Al2O3 1–2nm thick and 10–30nm long well dispersed in a microporous carbon matrix. The micropores network accounted for 63% of the total pore volume (DR isotherm). The c-CMSM exhibited ideal O2/N2 and C3H6/C3H8 permselectivities of 5 and 15, respectively. The performance of the c-CMSM for pair C3H6/C3H8 was above the upper bound curve for polymeric membranes, making it a promising vehicle for olefin purification. [Copyright &y& Elsevier]

A mechanism for the enhancement of the viscous dissipation rate of turbulent kinetic energy (TKE) in the oceanic boundary layer (OBL) is proposed, based on insights gained from rapid-distortion theory (RDT). In this mechanism, which complements mechanisms purely based on wave breaking, preexisting TKE is amplified and subsequently dissipated by the joint action of a mean Eulerian wind-induced shear current and the Stokes drift of surface waves, the same elements thought to be responsible for the generation of Langmuir circulations. Assuming that the TKE dissipation rate ℇε saturates to its equilibrium value over a time of the order one eddy turnover time of the turbulence, a new scaling expression, dependent on the turbulent Langmuir number, is derived for ℇε. For reasonable values of the input parameters, the new expression predicts an increase of the dissipation rate near the surface by orders of magnitude compared with usual surface-layer scaling estimates, consistent with available OBL data. These results establish on firmer grounds a suspected connection between two central OBL phenomena: dissipation enhancement and Langmuir circulations. [ABSTRACT FROM AUTHOR]

Several predictive GEmethods based on the group-contribution concept have been tested for prediction of multicomponent vapor–liquid equilibria (VLE) of fragrance mixtures. The evaluation covered 24 binary, 20 ternary, and 21 quaternary mixtures combining six different fragrances typically used in perfume formulation and ethanol as the solvent. The selected predictive methods are the original UNIFAC (updated to the last revision), the UNIFAC-Dortmund, the ASOG, and the A-UNIFAC. The equilibrium compositions were experimentally measured at 23 °C by headspace gas chromatography (HS-GC). For each liquid composition, the corresponding experimental and predicted vapor compositions were compared. This study confirmed that the UNIFAC method is the best predictive model for prediction of VLE, while the A-UNIFAC performed poorer than other evaluated methods for the mixtures studied in this work. Moreover, from the vapor composition the odor intensity and character of the fragrance mixtures was calculated using a previous developed model which considers the Stevens’ power law for the olfaction intensity scale and the stronger component model for quality perception. In this way, the odor intensity and character of fragrance mixtures was predicted and compared to experimental and sensorial evaluations. From this work it can be concluded that the UNIFAC and UNIFAC-Dortmund methods allow obtaining optimal predictions of the character of the fragrance mixtures with an agreement of 95.4% when compared to experimental measurements. [ABSTRACT FROM AUTHOR]

CO-releasing molecules (CO-RMs) were previously shown by us to be more potent bactericides than CO gas. This suggests a mechanism of action for CO-RM, which either potentiates the activity of CO or uses another CO-RM-specific effect. We have also reported that CORM-2 induces the expression of genes related to oxidative stress. In the present study we intend to establish whether the generation of reactive oxygen species by CO-RMs may indeed result in the inhibition of bacterial cellular function. We now report that two CO-RMs (CORM-2 and ALF062) stimulate the production of ROS in Escherichia coli, an effect that is abolished by addition of antioxidants. Furthermore, deletion of genes encoding E. coli systems involved in reactive oxygen species scavenging, namely catalases and superoxide dismutases, potentiates the lethality of CORM-2 due to an increase of intracellular ROS content. CORM-2 also induces the expression of the E. coli DNA repair/SOS system recA, and its inactivation enhances toxicity of CORM-2. Moreover, fluorescence microscopy images reveal that CORM-2 causes DNA lesions to bacterial cells. We also demonstrate that cells treated with CORM-2 contain higher levels of free iron arising from destruction of iron-sulfur proteins. Importantly, we show that CO-RMs generate hydroxyl radicals in a cell-free solution, a process that is abolished by scavenging CO. Altogether, we provide a novel insight into the molecular basis of CO-RMs action by showing that their bactericidal properties are linked to cell damage inflicted by the oxidative stress that they are able to generate. [ABSTRACT FROM AUTHOR]

Abstract: Typical industrial propylene streams contain 2–5 molar% of alkynes, which must be removed. Traditionally, this is carried out through hydrogenation. However, the deeper hydrogenation to alkanes is a drawback of such process. The use of a catalytic membrane reactor (MR) featuring a propyne permselective membrane and a catalyst selective to the propyne hydrogenation, loaded on the permeate side membrane surface is proposed; plug-flow pattern and segregated feed of reactants are considered. This strategy should improve the selective hydrogenation, as the permselective membrane enhances the propyne/propylene ratio at the catalyst surface. The combined process was analyzed using a mathematical model. The MR performance was compared to a conventional fixed-bed catalytic reactor (FBCR) with the same feed and reaction conditions, in terms of the propyne molar fraction. The performance of the MR was characterized by the conversion of propyne and selectivity towards propylene as a function of some model parameters. The MR showed to be more efficient in performing the required purification. [Copyright &y& Elsevier]

The success of food and beverage production processes carried out by Saccharomyces cerevisiae and the thriving of food spoilage fungi are dependent on the ability of a cell to cope with the many environmental insults imposed during food production and preservation processes. Post-genomic approaches, especially transcriptomics, proteomics and chemogenomics, applied to S. cerevisiae made possible the unveiling of general and specific genome-wide adaptive response programs against stress induced by weak acids, ethanol, sulfite, heat and cold shock, osmotic pressure and nutrient limitation. These programs and the underlying signaling pathways are overviewed herein, highlighting the recent identification of genes and pathways found to be involved in stress response and tolerance. These are good candidate targets for genetic engineering aiming at the development of improved strains. The extension of the data gathered in S. cerevisiae to food spoilage fungi is considered. The relevance of the different genome-wide approaches in this context is also discussed. [Copyright &y& Elsevier]

The ability of an iron-impregnated ion exchange bead (PWX5) to remove As(V) from ground water was investigated. The effects of particle size, solution pH, As(V) concentration, competition, adsorbent concentration, temperature, iron content, and iron accessibility on removal kinetics and/or equilibrium were determined. PWX5's performance was compared to other iron-based adsorbents, primarily Bayoxide® E-33 (E-33), a granular ferric oxide, for arsenic removal performance. All of the factors cited impacted either the amount of As(V) adsorbed or the rate of adsorption. Stirred batch reactor data showed the rate of adsorption increased as particle size decreased and bottle point isotherm data showed As(V) adsorption maximum capacity increased with higher initial adsorbate concentration. The presence of phosphate and silicate reduced the amount of As(V) adsorbed as did a pH > 7.0. PWX5 is durable, rather homogeneous in size and effective at removing As(V). It is a viable alternative to E-33 which has a wider size distribution and wears more easily. [ABSTRACT FROM AUTHOR]

Abstract: An alternative complex III (ACIII) is a respiratory complex with quinol:electron acceptor oxidoreductase activity. It is the only example of an enzyme performing complex III function that does not belong to bc 1 complex family. ACIII from Rhodothermus (R.) marinus was the first enzyme of this type to be isolated and characterized, and in this work we deepen its characterization. We addressed its interaction with quinol substrate and with the caa 3 oxygen reductase, whose coding gene cluster follows that of the ACIII. There is at least, one quinone binding site present in R. marinus ACIII as observed by fluorescence quenching titration of HQNO, a quinone analogue inhibitor. Furthermore, electrophoretic and spectroscopic evidences, taken together with mass spectrometry revealed a structural association between ACIII and caa 3 oxygen reductase. The association was also shown to be functional, since quinol:oxygen oxidoreductase activity was observed when the two isolated complexes were put together. This work is thus a step forward in the recognition of the structural and functional diversities of prokaryotic respiratory chains. [Copyright &y& Elsevier]

In this paper, we seek to examine the causes of civic engagement, which refers to a set of actions and efforts, a feeling of belonging, and an experience of investment and ownership in local, regional, national, or international communities. We propose that research on the determinants of civic engagement has missed an important independent variable, which is residential satisfaction. Building upon insights from residential satisfaction research, we hypothesize that the more satisfaction an individual has with their community, the more likely it is that they will be civically engaged. We test this theory with a hierarchical regression model. While the regression produced mixed results, our findings suggest that satisfaction with social offerings leads to an increase in civic engagement. [ABSTRACT FROM AUTHOR]

This paper is centred on the relationship between infrastructures and space. It aims especially to understand the new realities emerging in space given the advances made in the infrastructure sector, which has been heavily inluenced by new Information and Communications Technology (ICT). The paper describes the new characteristics of urban infrastructures, identifying the structural changes. The relations among infrastructures, territory and development are analysed, at the start of a new cycle characterised by the phenomenon of globalisation, intense socioeconomic and territorial transformations. [ABSTRACT FROM AUTHOR]

The direct impact of mountain waves on the atmospheric circulation is due to the deposition of wave momentum at critical levels, or levels where the waves break. The first process is treated analytically in this study within the framework of linear theory. The variation of the momentum flux with height is investigated for relatively large shears, extending the authors’ previous calculations of the surface gravity wave drag to the whole atmosphere. A Wentzel–Kramers–Brillouin (WKB) approximation is used to treat inviscid, steady, nonrotating, hydrostatic flow with directional shear over a circular mesoscale mountain, for generic wind profiles. This approximation must be extended to third order to obtain momentum flux expressions that are accurate to second order. Since the momentum flux only varies because of wave filtering by critical levels, the application of contour integration techniques enables it to be expressed in terms of simple 1D integrals. On the other hand, the momentum flux divergence (which corresponds to the force on the atmosphere that must be represented in gravity wave drag parameterizations) is given in closed analytical form. The momentum flux expressions are tested for idealized wind profiles, where they become a function of the Richardson number (Ri). These expressions tend, for high Ri, to results by previous authors, where wind profile effects on the surface drag were neglected and critical levels acted as perfect absorbers. The linear results are compared with linear and nonlinear numerical simulations, showing a considerable improvement upon corresponding results derived for higher Ri. [ABSTRACT FROM AUTHOR]

The understanding of the molecular mechanisms underlying acquired herbicide resistance is crucial in dealing with the emergence of resistant weeds. Saccharomyces cerevisiae has been used as a model system to gain insights into the mechanisms underlying resistance to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The TPO1 gene, encoding a multidrug resistance (MDR) plasma membrane transporter of the major facilitator superfamily (MFS), was previously found to confer resistance to 2,4-D in yeast and to be transcriptionally activated in response to the herbicide. In this work, we demonstrate that Tpo1p is required to reduce the intracellular concentration of 2,4-D. ScTpo1p homologs encoding putative plasma membrane MFS transporters from the plant model Arabidopsis thaliana were analyzed for a possible role in 2,4-D resistance. At5g13750 was chosen for further analysis, as its transcript levels were found to increase in 2,4-D stressed plants. The functional heterologous expression of this plant open reading frame in yeast was found to confer increased resistance to the herbicide in Δtpo1 and wild-type cells, through the reduction of the intracellular concentration of 2,4-D. Heterologous expression of At5g13750 in yeast also leads to increased resistance to indole-3-acetic acid (IAA), Al3+ and Tl3+. At5g13750 is the first plant putative MFS transporter to be suggested as possibly involved in MDR. [ABSTRACT FROM AUTHOR]

The understanding of the molecular basis of yeast resistance to ethanol may guide the design of rational strategies to increase process performance in industrial alcoholic fermentations. In this study, the yeast disruptome was screened for mutants with differential susceptibility to stress induced by high ethanol concentrations in minimal growth medium. Over 250 determinants of resistance to ethanol were identified. The most significant gene ontology terms enriched in this data set are those associated with intracellular organization, biogenesis, and transport, in particular, regarding the vacuole, the peroxisome, the endosome, and the cytoskeleton, and those associated with the transcriptional machinery. Clustering the proteins encoded by the identified determinants of ethanol resistance by their known physical and genetic interactions highlighted the importance of the vacuolar protein sorting machinery, the vacuolar H+-ATPase complex, and the peroxisome protein import machinery. Evidence showing that vacuolar acidification and increased resistance to the cell wall lytic enzyme β-glucanase occur in response to ethanol-induced stress was obtained. Based on the genome-wide results, the particular role of the FPS1 gene, encoding a plasma membrane aquaglyceroporin which mediates controlled glycerol efflux, in ethanol stress resistance was further investigated. FPSI expression contributes to decreased [3H]ethanol accumulation in yeast cells, suggesting that Fps1p may also play a role in maintaining the intracellular ethanol level during active fermentation. The increased expression of FPS1 confirmed the important role of this gene in alcoholic fermentation, leading to increased final ethanol concentration under conditions that lead to high ethanol production. [ABSTRACT FROM AUTHOR]

Abstract: A simple diffusion model based on Fick''s Law for diffusion was developed to simulate the evaporation/diffusion rate of small volumes of perfume liquid mixtures over time and distance. Thermodynamic UNIFAC model was used to predict the vapor–liquid equilibrium, since fragrance solutions were considered as non-ideal liquid mixtures. The diffusion model was applied to concentrated perfume mixtures but also to quaternary mixtures, considering the existence of a solvent matrix (ethanol). The PTD® methodology was applied to the study of the perfume evaporation and interpreted along with evaporation lines (EL) that traced the evaporation path of the perfume mixture. The performance of the perfume mixtures studied in this work was analyzed considering the odor intensity and lastingness of the odorants at different distances from the simulated point of application of the perfume and over time. Perfumery performance parameters, namely impact, tenacity, diffusion and volume, were studied in the light of the diffusion model. The use of fixatives and different base notes in the formulation of the perfume and their role on the performance was studied as well as the impact of the ethanol matrix in fragranced mixtures. [Copyright &y& Elsevier]

This paper is centred on the relationship between new communication and information technologies (ICT) and spatial planning, particularly in what concerns the valorisation of ICT in planning objectives and practices. Assuming that is desirable to achieve a deeper understanding of the impact of ICT on planning in face of the importance of the so-called network society, its effects on spatial restructuring, and the changing nature of planning, this paper focus on the complex interactions between ICT development and planning change, relying on recent theoretical analysis. [ABSTRACT FROM AUTHOR]