5,135 research outputs found
Clustering and dynamics of cytochrome bd-I complexes in the Escherichia coli plasma membrane in vivo.
No full textThe cytochrome bd-I complex of Escherichia coli is a respiratory terminal oxidase and an integral component of the cytoplasmic membrane. As with other respiratory components, the organization and dynamics of this complex in living membranes is unknown. We set out to visualize the distribution and dynamics of this complex in vivo. By exchanging cydB for cydB-gfpgcn4 on the E. coli chromosome, we produced a strain (YTL01) that expresses functional GFP-tagged cytochrome bd-I terminal oxidase complexes under wild-type genetic control. We imaged live YTL01 cells using video-rate epifluorescence and total internal reflection fluorescence (TIRF) microscopy in combination with fluorescence recovery after photobleaching (FRAP) and saw mobile spots of GFP fluorescence in plasma membranes. Numbers of GFP molecules per spot were quantified by step-wise photobleaching giving a broad distribution with a mean of approximately 76, indicating that cytochrome bd-I is concentrated in mobile patches in the E. coli plasma membrane. We hypothesize that respiration occurs in mobile membrane patches which we call 'respirazones'
Mitigation of greenhouse gas emissions from agricultural fields through bioresource management
No full textEfficient bioresource management can alter soil biochemistry and soil physical properties, leading to reduced greenhouse gas (GHG) emissions from agricultural fields. The objective of this study was to evaluate the role of organic amendments including biodigestate (BD), biochar (BC), and their combinations with inorganic fertilizer (IF) in increasing carbon sequestration potential and mitigation of GHG emissions from potato (Solanum tuberosum) fields. Six soil amendments including BD, BC, IF, and their combinations BDIF and BCIF, and control (C) were replicated four times under a completely randomized block design during the 2021 growing season of potatoes in Prince Edward Island, Canada. An LI-COR gas analyzer was used to monitor emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from treatment plots. Analysis of variance (ANOVA) results depicted higher soil moisture-holding capacities in plots at relatively lower elevations and comparatively lesser volumetric moisture content in plots at higher elevations. Soil moisture was also impacted by soil temperature and rainfall events. There was a significant effect of events of data collection, i.e., the length of the growing season (p-value ≤ 0.05) on soil surface temperature, leading to increased GHG emissions during the summer months. ANOVA results also revealed that BD, BC, and BCIF significantly (p-value ≤ 0.05) sequestered more soil organic carbon than other treatments. The six experimental treatments and twelve data collection events had significant effects (p-value ≤ 0.05) on the emission of CO2. However, the BD plots had the least emissions of CO2 followed by BC plots, and the emissions increased with an increase in atmospheric/soil temperature. Results concluded that organic fertilizers and their combinations with inorganic fertilizers help to reduce the emissions from the agricultural soils and enhance environmental sustainability.Atlantic Canada Opportunities AgencyDepartment of Environment, Energy and Climate Action, Government of Prince Edward Islan
Cytochrome bd displays significant quinol peroxidase activity
No full textCytochrome bd is a prokaryotic terminal oxidase that catalyses the electrogenic reduction of oxygen to water using ubiquinol as electron donor. Cytochrome bd is a tri-haem integral membrane enzyme carrying a low-spin haem
Flows of singular vector fields and applications to fluid and kinetic equations
No full textSeveral physical phenomena arising in fluid dynamics and kinetic equations can be modeled by nonlinear transport PDE. Such quantities are the vorticity of a fluid, or the density of a collection of particles advected by a velocity field which is highly irregular. The theory of characteristics provides a link between this PDE and the ODE dX/dt=b(t,X(t,x)), where b is the velocity field. When b has Sobolev or BV regularity and bounded divergence, the theory of DiPerna-Lions and Ambrosio gives a good notion of solution to the ordinary differential equation using the concept of regular Lagrangian flow. Extending the results of Crippa-DeLellis, and more recently Bouchut-Crippa, we study Lagrangian flows associated to velocity fields with anisotropic regularity: those with gradient given by the singular integral of an L^1 function in some directions, and the singular integral of a measure in others. We exploit an anisotropic version of the previous arguments and estimate the difference quotients in this context, thereby gaining quantitative estimates in terms of the given regularity bounds. One then recovers well-posedness for the ordinary differential equation. This answers positively the question of existence of Lagrangian solutions to the Vlasov Poisson and Euler equations with L^1 data
Lymphatic density (LD; a) and blood vessel density (BD; b) in the myocardium
No full text, LDs in the normal myocardium and the seven categorized stages. LD means the total number of D2-40+ lymphatics in 20 fields of view observed by light microscopy at ×200 magnification. The values of LD are 21.2 ± 6.2 in the normal myocardial tissue (Normal), 7.6 ± 4.2 in Stage I, 0 in Stage II, 0 in Stage III, 1.3 ± 1.5 in Stage IV, 22.3 ± 25.7 in Stage V, 29.7 ± 25.0 in Stage VI and 20.8 ± 13.4 in Stage VII. There is no statistical difference between LD values in Stages V, VI and VII. Statistical analyses were performed by Student's -test. * 0.0001; ** 0.05. , Blood vessel density (BD) in the normal myocardium and the seven categorized stages. BD means the total number of CD34+ blood vessels counted by the same methods as the value of lymphatic density. The values of BD are 2693.4 ± 197.0 in Normal, 1689.9 ± 640.7 in Stage I, 571.4 ± 478.3 in Stage II, 51.8 ± 30.5 in Stage III, 1430.8 ± 323.1 in Stage IV, 1292.7 ± 153.1 in Stage V, 509.9 ± 276.3 in Stage VI and 130.5 ± 83.8 in Stage VII. After the onset of myocardial infarction, the BD value decreased up to Stage III. The BD values increased in Stage IV compared with Stage III, but decreased with the advance of the healing process of infarcted lesion up to Stage VII. Statistical analyses were performed by Student's -test. * 0.001; ** 0.0001.<p><b>Copyright information:</b></p><p>Taken from "Lymphangiogenesis in myocardial remodelling after infarction"</p><p></p><p>Histopathology 2007;51(3):345-353.</p><p>Published online 01 Sep 2007</p><p>PMCID:PMC2366023.</p><p>© 2007 The Authors. Journal compilation 2007 Blackwell Publishing Limited.</p
Continuity equations and ODE flows with non-smooth velocity
No full textIn this paper we review many aspects of the well-posedness theory for the Cauchy problem for the continuity and transport equations and for the ordinary differential equation (ODE). In this framework, we deal with velocity fields that are not smooth, but enjoy suitable 'weak differentiability' assumptions. We first explore the connection between the partial differential equation (PDE) and the ODE in a very general non-smooth setting. Then we address the renormalization property for the PDE and prove that such a property holds for Sobolev velocity fields and for bounded variation velocity fields. Finally, we present an approach to the ODE theory based on quantitative estimates
BD Rhapsody WTA AbSeq Analysis
No full text<p>Dataset and codes for BD Rhapsody single cell analysis system.</p>
<p>Disclaimer: The set of codes are optimised for the associated dataset only. For detailed understanding of the analysis procesure, please refer to https://github.com/INGEN-HOPE/Single-Cell-Multi-Omics-Data-Analysis-for-BD-Rhapsody. For any kind queries, please refer to the corresponding author, or post your query on our GitHub page.</p>
DIOPHANTINE APPROXIMATION IN IMAGINARY QUADRATIC FIELDS
No full text Let H3 be the upper half-space model of the three-dimensional hyperbolic space. For certain cocompact Fuchsian subgroups Γ of an extended Bianchi group Bd, the extremality of the axis of hyperbolic F ∈ Γ in H3 with respect to Γ implies its extremality with respect to Bd. This reduction is used to obtain sharp lower bounds for the Hurwitz constants and lower bounds for the highest limit points in the Markov spectra of Bd for some d < 1000. In particular, such bounds are found for all non-Euclidean class one imaginary quadratic fields. The Hurwitz constants for the imaginary quadratic fields with discriminants -120 and -132 are given. The second minima are also indicated for these fields. </jats:p
Rheological properties and stabilization of magnetorheological fluids in a water-in-oil emulsion
No full textThe rheological properties and dispersion stability of magnetorheological (MR) fluids consisting of hydrophilic treated carbonyl iron particles dispersed in a water-in-oil emulsion were studied for the first time by the use of a stress-controlled rheometer and sedimentation test. In order to improve the stability of the MR fluids, carbonyl iron magnetic particles were chemisorbed by TWeen 80 and a water-in-oil emulsion was employed as a continuous phase for MR fluids. Attraction between hydrophilic-treated carbonyl iron and water emulsion in continuous phase plays a critical role in greatly improving stability of dense carbonyl iron particles against sedimentation without restricting rheological properties. On application of magnetic fields, the suspensions show a striking increase in viscosity. Since constant stress is generated within the limit of zero shear rate, the plateau in the flow curve corresponds to the Bingham yield stress. Under a low external magnetic field, the yield stress varied as B-3/2, indicating that local magnetization saturation occurs between the neighboring magnetized particles. The yield stress has an approximately linear relation to the particle volume fraction. (C) 2001 Academic Press
Properties and powers
No full textThis thesis concerns the relation between the fundamental properties and the powers they confer. The views
considered are introduced in terms of their acceptance or rejection of the quiddistic thesis. Essentially the
quiddistic thesis claims that properties confer the powers they do neither necessarily nor sufficiently.
Quidditism is the view that accepts the quiddistic thesis. The other two views to be considered, the pure powers
view and the grounded view reject the quiddistic thesis. The pure powers view supports its denial of the
quiddistic thesis with the claim that properties consist in conferring the powers they do; the possession of a
property just is the possession of a power. The grounded view, the positive view of this thesis, rejects the idea
that properties are constituted by conferring the causal powers they do. Rather on the grounded view, it is the
natures of the fundamental properties that metaphysically explain why they confer the powers they do
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