A feasibility of a membrane-aerated biofilm reactor (MABR) for controllable nitrification was examined. The estimation of oxygen supply rate (OSR) with three polyacrylonitrile membrane modules ...revealed that specific OSR was equivalent in these membrane modules and OSR affected only air pressure, thus enabling control of aeration simply by adjustment of air pressure. A continuous nitrification experiment consisting of three reactors differing in membrane surface area investigated the reactor performance of the MABR at an air pressure of 23
kPa. The results indicated that the ammonia removal rate at steady state was dependent on membrane surface area, at rates nearly equivalent to that predicted by the above OSR experiment. The amount of bacteria adhering to the membrane surface was not completely proportional to membrane surface area due to clogging in a reactor with high membrane surface area, which accompanies a decrease in specific ammonia removal rate per biomass with membrane surface area. Stable ammonia removal rates at air pressures of 23, 45 and 100
kPa corresponded to the predicted values from the OSR experiment. Further, more than 80% oxygen utilization efficiency (OUE) was achieved under all operational conditions, indicating effective oxygen uptake by nitrifying bacteria under oxygen-depleted conditions. Based on these experiments, the MABR was shown to be a controllable nitrification system, and to be able to provide a reaction space for nitrification in a membrane-attached biofilm without altering the bulk conditions.
•FexCo1−x nanostructures on Pt(111) are investigated by ab initio DFT calculations.•Dimensionality and stoichiometry trends on the magnetic properties are here obtained.•Nearest neighbor Fe/Co ...exchange couplings are shown to be strongly ferromagnetic.•Nonlinear decrease of mean orbital moments with Fe compact clusters concentration.
The behavior of local magnetic moments and exchange coupling parameters of FexCo1-x nanostructures (nanowires and compact clusters) on the fcc Pt(111) surface is here investigated using the first-principles real-space RS-LMTO-ASA method, in the framework of the DFT. Different configurations of FexCo1-x trimers and heptamers on Pt(111) are considered, varying the positions and the concentration of Fe or Co atoms. We discuss the influence of dimensionality and stoichiometry changes on the magnetic properties, specially on the orbital moments, which are very important in establishing a nanoscopic understanding of delocalized electron systems. We demonstrate the existence of a strictly decreasing nonlinear trend of the average orbital moments with the Fe concentration for the compact clusters, different from what was found for FexCo1-x nanowires on Pt(111) and also for corresponding higher-dimensional systems (FexCo1-x monolayer on Pt(111) and FexCo1-x bulk). The average spin moments, however, are invariably described by a linear function with respect to stoichiometry. In all studied cases, the nearest neighbors exchange couplings have shown to be strongly ferromagnetic.
The magnetic properties of Mn nanostructures on the Fe(001) surface have been studied using the noncollinear first-principles real space-linear muffin-tin orbital-atomic sphere approximation method ...within density-functional theory. We have considered a variety of nanostructures such as adsorbed wires, pyramids, and flat and intermixed clusters of sizes varying from two to nine atoms. Our calculations of interatomic exchange interactions reveal the long-range nature of exchange interactions between Mn-Mn and Mn-Fe atoms. We have found that the strong dependence of these interactions on the local environment, the magnetic frustration, and the effect of spin-orbit coupling lead to the possibility of realizing complex noncollinear magnetic structures such as helical spin spiral and half-skyrmion.
The variable line spacing plane grating monochromator beamline at the Canadian Light Source (CLS) employs three grazing incidence variable line spacing gratings to cover a photon energy range of ...5-250 eV. It uses a 185 mm period length planar permanent magnet insertion device as the photon source, sharing a straight section with another soft x-ray beamline at the CLS. The commissioning and performance of the beamline is reported. The high resolution photoabsorption spectra of Ar and PF(5) gases are reported. A resolving power of over 40,000 for photons in the low energy region and >10,000 for a wider energy range (8-200 eV) can be achieved. A photon flux of up to 2 x 10(12) photons/s per 100 mA with slit settings of 50 microm has been measured.
Biodegradable poly
d,
l-lactic acid (PLA, molecular weight: ca. 5000) microcapsules containing a CXCR4 antagonist (4F-benzoyl-TE14011) were prepared (4F-benzoyl-TE14011-PLA), and their ...anti-metastatic activity was evaluated in mice. A single subcutaneous administration of 4F-benzoyl-TE14011-PLA significantly reduced the number of colonies formed by pulmonary metastasis of B16–BL6 melanoma cells expressing CXCR4. The same dose of 4F-benzoyl-TE14011 in a single or a series of treatments affected little. The substance 4F-benzoyl-TE14011 dose-dependently suppressed B16–BL6 cell growth. In the cells cultured with SDF-1, a more potent suppression was observed. 4F-Benzoyl-TE14011 was rapidly released from 4F-benzoyl-TE14011-PLA for an initial period, both in vitro and in vivo. A steady release was thereafter observed. Therefore, this drug release profile might contribute to prevention of melanoma metastasis at the steps involving the migration and cell growth. These results also show that a sustained drug release formulation could be a useful drug delivery system for CXCR4 antagonists.
A model for the selective adsorption phenomenon in an isotropic liquid accounting for a van der Waals interaction between the ions and the surface is presented, in the framework of the ...Poisson−Boltzmann theory. The fundamental equations governing the electric field distribution are exactly solved for low and high potential regimes.
Updated core libraries of the ALPS project Gaenko, A.; Antipov, A.E.; Carcassi, G. ...
Computer physics communications,
April 2017, 2017-04-00, 2017-04-01, Letnik:
213, Številka:
C
Journal Article
Recenzirano
Odprti dostop
The open source ALPS (Algorithms and Libraries for Physics Simulations) project provides a collection of physics libraries and applications, with a focus on simulations of lattice models and strongly ...correlated systems. The libraries provide a convenient set of well-documented and reusable components for developing condensed matter physics simulation code, and the applications strive to make commonly used and proven computational algorithms available to a non-expert community. In this paper we present an updated and refactored version of the core ALPS libraries geared at the computational physics software development community, rewritten with focus on documentation, ease of installation, and software maintainability.
Program Title: ALPS Core libraries
Program Files doi:http://dx.doi.org/10.17632/fckj5d7wtr.1
Programming language: C++
Licensing provisions: GNU GPLv3
Nature of problem: Need for modern, lightweight, tested and documented libraries covering the basic requirements of rapid development of efficient physics simulation codes, especially for modeling strongly correlated electron systems.
Solution method: We present a C++ open source computational library that provides a convenient set of components for developing parallel physics simulation code. The library features a short development cycle and up-to-date user documentation.
External routines/libraries:CMake, MPI, Boost, HDF5.
Treatment of the Agrobacterium tumefaciens ADP-glucose pyrophosphorylase with the arginyl reagent phenylglyoxal resulted in complete desensitization to fructose 6-phosphate (F6P) activation, and ...partial desensitization to pyruvate activation. The enzyme was protected from desensitization by ATP, F6P, pyruvate, and phosphate. Alignment studies revealed that this enzyme contains arginine residues in the amino-terminal region that are relatively conserved in similarly regulated ADP-glucose pyrophosphorylases. To functionally evaluate the role(s) of these arginines, alanine scanning mutagenesis was performed to generate the following enzymes: R5A, R11A, R22A, R25A, R32A, R33A, R45A, and R60A. All of the enzymes, except R60A, were successfully expressed and purified to near homogeneity. Both the R5A and R11A enzymes displayed desensitization to pyruvate, partial activation by F6P, and increased sensitivity to phosphate inhibition. Both the R22A and R25A enzymes exhibited reduced V max values in the absence of activators, lower apparent affinities for ATP and F6P, and reduced sensitivities to phosphate. The presence of F6P restored R22A enzyme activity, while the R25A enzyme exhibited only ∼1.5% of the wild-type activity. The R32A enzyme displayed an ∼11.5-fold reduced affinity for F6P while exhibiting behavior identical to that of the wild type with respect to pyruvate activation. Both the R33A and R45A enzymes demonstrated a higher activity than the wild-type enzyme in the absence of activators, no response to F6P, partial activation by pyruvate, and desensitization to phosphate inhibition. These altered enzymes were also insensitive to phenylglyoxal. The data demonstrate unique functional roles for these arginines and the presence of separate subsites for the activators.
The study demonstrated that lipid microspheres (LM) containing rifampicin (LM-RFP) could deliver the drug to alveolar macrophages in vitro and in vivo, and that intranasal administration to animals ...could achieve preferential accumulation in the lungs with less effect on the liver. The LM-RFP particles had a mean diameter of 247.2 ± 75.7 nm, and their size remained stable when stored at 4°C or 25°C for at least 4 weeks. In vitro uptake of 3HLM-RFP by alveolar macrophages was over 4 times higher than that of unencapsulated 3HRFP, whereas the in vivo uptake was 30 times higher. Flow cytometric analysis and confocal laser scanning microscopy confirmed that LM could deliver the encapsulated drug effectively to alveolar macrophages in vitro and in vivo Intranasal administration of 3HLM-RFP to normal mice resulted in preferential pulmonary uptake of the drug and lower levels in the blood and liver compared with administration of unencapsulated 3HRFP. In conclusion, LM-RFP could be a promising preparation for delivery via the respiratory tract to tuberculosis (TB) and TB/HIV patients.
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