13,988 research outputs found
Clyde Police Chief Harold Kramer
No full textClyde Police Chief Harold Kramer will retire on February 26, 1982 after almost 25 years with the department. He started as a part-time employee and became a full-time officer in 1958
An intracellular pH gradient in the anammox bacterium Kuenenia stuttgartiensis as evaluated by (31)P NMR
No full textThe cytoplasm of anaerobic ammonium oxidizing (anammox) bacteria consists of three compartments separated by membranes. It has been suggested that a proton motive force may be generated over the membrane of the innermost compartment, the “anammoxosome”. 31P nuclear magnetic resonance (NMR) spectroscopy was employed to investigate intracellular pH differences in the anammox bacterium Kuenenia stuttgartiensis. With in vivo NMR, spectra were recorded of active, highly concentrated suspensions of K. stuttgartiensis in a wide-bore NMR tube. At different external pH values, two stable and distinct phosphate peaks were apparent in the recorded spectra. These peaks were equivalent with pH values of 7.3 and 6.3 and suggested the presence of a proton motive force over an intracytoplasmic membrane in K.stuttgartiensis. This study provides for the second time—after discovery of acidocalcisome-like compartments in Agrobacterium tumefaciens—evidence for an intracytoplasmic pH gradient in a chemotrophic prokaryotic cell.BiotechnologyApplied Science
Sulfate-Sulfur Content and pH of Rainwater at a Forested Site in Northern Minnesota
No full textPublished as Miscellaneous Journal Paper Series No. 1743 of the Minnesota Agricultural Experiment Station.White, Edwin H.; Kramer, Charles F.. (1980). Sulfate-Sulfur Content and pH of Rainwater at a Forested Site in Northern Minnesota. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/58354
Influence of pH, multivalent counter ions, and membrane fouling on phosphate retention during ceramic nanofiltration
No full textCeramic nanofiltration is an emerging technology for the recovery of water and nutrients (including phosphate) from municipal sewage which becomes more imperative worldwide. In order to use ceramic nanofiltration for phosphate recovery from municipal sewage, more knowledge is needed. This is the first paper reporting the phosphate retention of ceramic nanofiltration membranes. Furthermore, the influence of pH, multivalent counter ions, and membrane fouling on phosphate retention is reported in this paper. Various experiments were executed to analyse the phosphate retention and zeta potential under varying conditions. During filtration of a salt solution including phosphate, the phosphate retention increased, from 76% to 99%, with a change in pH from 5 to 9. Furthermore, magnesium ions and organic fouling had a large influence on the phosphate retention: at pH 7 the phosphate retention dropped from 92% to 42–43% due to the presence of either magnesium ions or organic fouling.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Sanitary Engineerin
Solid Supported Membranes Doped with PIP2: Influence of Ionic Strength and pH on Bilayer Formation and Membrane Organization
No full textPhosphoinositides and in particular L-alpha-phosphatidylinositol-4,5-bisphosphate (PIP2) are key lipids controlling many cellular events and serve as receptors for a large number of intracellular proteins. To quantitatively analyze protein-PIP2 interactions in vitro in a time-resolved manner, planar membranes on solid substrates are highly desirable. Here, we describe an optimized protocol to form PIP2 containing planar solid supported membranes on silicon surfaces by vesicle spreading. Supported lipid bilayers (SLBs) were obtained by spreading POPC/PIP2 (92:8) small unilamellar vesicles onto hydrophilic silicon substrates at a low pH of 4.8. These membranes were capable of binding ezrin, resulting in large protein coverage as concluded from reflectometric interference spectroscopy and fluorescence microscopy. As deduced from fluorescence microscopy, only under low pH conditions, a homogeneously appearing distribution of fluorescently labeled PIP2 molecules in the membrane was achieved. Fluorescence recovery after photobleaching experiments revealed that PIP2 is not mobile in the bottom layer of the SLBs, while PIP2 is fully mobile in the top layer with diffusion coefficients of about 3 mu m(2)/s. This diffusion coefficient was considerably reduced by a factor of about 3 if ezrin has been bound to PIP2 in the membrane
REACTION-MECHANISM OF THE RECONSTITUTED TRICARBOXYLATE CARRIER FROM RAT-LIVER MITOCHONDRIA
No full textBISACCIA F, DEPALMA A, Dierks T, KRAMER R, PALMIERI F. REACTION-MECHANISM OF THE RECONSTITUTED TRICARBOXYLATE CARRIER FROM RAT-LIVER MITOCHONDRIA. BIOCHIMICA ET BIOPHYSICA ACTA. 1993;1142(1-2):139-145.Transport of citrate and malate by the tricarboxylate carrier from rat liver mitochondria has been studied in a reconstituted system. Homologous citrate/citrate antiport and heterologous (electroneutral) citrate/malate antiport was kinetically analyzed. The maximal rates of the two exchange modes did not vary significantly within pH 7.0 to 7.8 which is the optimum pH-range for transport activity. On the other hand, the apparent transport affinity varied considerably within this range. Calculations on the basis of the different pK values for citrate and malate indicate that only H-citrate 2 -and malate 2 -are accepted as transport species by the tricarboxylate carrier. A complete set of half-saturation constants was established for citrate and malate on both the external and the internal side of the membrane. Both the K(m) and V(max) for citrate and malate were independent of the nature of the countersubstrate at the other side of the membrane. Bisubstrate initial velocity analyses of the exchange reaction resulted in a kinetic pattern which is consistent with a sequential antiport mechanism. This type of mechanism implies formation of a ternary complex of the carrier with two substrate molecules before the transport reaction occurs. Thus the tricarboxylate carrier falls into the functional family of mitochondrial carrier proteins showing sequential transport mechanisms
Concept and development of an autonomous wearable micro-fluidic platform for real time pH sweat analysis
No full textIn this work the development of an autonomous, robust and wearable micro-fluidic platform capable of performing on-line analysis of pH in sweat is discussed. Through the means of an optical detection system based on a surface mount light emitting diode (SMD LED) and a light photo sensor as a detector, a wearable system was achieved in which real-time monitoring of sweat pH was performed during 55 minutes of cycling activity. We have shown how through systems engineering, integrating miniaturised electrical components, and by improving the micro-fluidic chip characteristics, the wearability, reliability and performance of the micro-fluidic platform was significantly improved
Exploring the effect of the pH on the corrosion of multilayer nickel-chromium coatings
No full textThe impact of the pH on the corrosion of microporous nickel-chromium coatings has been explored at localised scale by Scanning Electrochemical Microscopy and validated by potentiodynamic polarisation measurements. Results not only reveal the correlation between both techniques but also enables to identify the different corrosion rate after increasing the electrolyte aggressiveness varying the pH. However, independently of the pH, a similar corrosion mechanism was determined: the cross-section micrographs (by Field Emission-Scanning Electron Microscope) have revealed an isotropic growth of the actives sites at early-stage corrosion as well as the attack of different nickel layers during the corrosion propagation.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Team Yaiza Gonzalez Garci
Il dibattito italiano su principi e clausole generale e l'ideale della certezza del diritto
No full textThis essay provides a critical assessment of the current Italian debate on general clauses and principles as set forth in a recent book edited by Giovanni D’Amico. The Author focuses on the role that legal certainty has played so far in this discussion and suggests that its impact on real life decisions and the functioning of the legal system has been greatly undervalued. The essay’s central argument attempts to demonstrate that, in the interpretation of general clauses and their translation into specific rules, the objective of legal certainty should be pursued and can ultimately be achieved
Dynamics of Network Formation Processes in the Co-Author Model
No full textThis article studies the dynamics in the formation processes of a mutual consent network in game theory setting: the Co-Author Model. In this article, a limited observation is applied and analytical results are derived. Then, 2 parameters are varied: the number of individuals in the network and the initial probability of the links in the network in its initial state. A simulation result shows a finding that is consistent with an analytical result for a state of equilibrium while it also shows different possible equilibria.Dynamics, Network, Game Theory, Model,Simulation, Equilibrium, Complexity
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