Universal method for synthesis of artificial gel antibodies by the imprinting approach combined with a unique electrophoresis technique for detection of minute structural differences of proteins, viruses, and cells (bacteria): Ia. gel antibodies against proteins (transferrins)

Artificial antibodies in the form of gel granules were prepared by the molecular imprinting technique from the monomers acrylamide and N,N'-methylene-bis-acrylamide. Gel granules, freed from the selectively adsorbed protein (the antigen), are neutral and, accordingly, do not migrate in an electrical field. However, upon selective interaction with the antigen at a pH different from its pI, the granules become charged. The selectivity of the gel antibodies was studied by free zone electrophoresis in a tube with inside diameter larger than the size of the granules. Such electrophoretic analyses showed that gel antibodies against iron-free transferrin had a high selectivity for this protein, although some crossreaction took place with iron-saturated transferrin, indicating that these artificial antibodies can easily distinguish the minute differences in the 3-D structure of the transferrins. Analogously, gel antibodies against iron-saturated transferrin were highly selective for this protein with some crossreaction with iron-free transferrin. The mobilities of iron-free and iron-saturated transferrin are very similar, and, therefore, capillary free zone electrophoresis cannot distinguish between these structurally related proteins. However, significant differences in the mobilities of the selective gel granules can be observed depending on their interaction with iron-free or iron-saturated transferrin, i.e., the artificial gel antibodies may become powerful analytical tools.     

Glottal closure, transglottal airflow, and voice quality in healthy middle-aged women

Seventeen healthy women, 45 to 61 years old, were examined using videofiberstroboscopy during phonation at three loudness levels. Two phoniatricians evaluated glottal closure using category and ratio scales. Transglottal airflow was studied by inverse filtering of the oral airflow signal recorded in a flow mask (Glottal Enterprises System) during the spoken phrase /ba:pa:pa:pa:p/ at three loudness levels. Subglottal pressure was estimated from the intraoral pressure during p occlusion. Running speech and the repeated /pa:/ syllables were perceptually evaluated by three speech pathologists regarding breathiness, hypo-, and hyperfunction, using continuous scales. Incomplete glottal closure was found in 35 of 46 phonations (76%). The degree of glottal closure increased significantly with raised loudness. Half of the women closed the glottis completely during loud phonation. Posterior glottal chink (PGC) was the most common gap configuration and was found in 28 of 46 phonations (61%). One third of the PGCs were in the cartilaginous glottis (PGCc) only. Two thirds extended into the membranous portion (PGCm); most of these occurred during soft phonation. Peak flow, peak-to-peak (AC) flow, and the maximum rate of change for the flow in the closing phase increased significantly with raised loudness. Minimum flow decreased significantly from normal to loud voice. Breathiness decreased with increased loudness. The results suggest that the incomplete closure patterns PGCc and PGCm during soft phonation ought primarily to be regarded as normal for Swedish women in this age group.     

Open and covered singing as studied by means of fiberoptics, inverse filtering, and spectral analysis

Covering the voice near the passaggio is a technique mainly used in male classic Western singing. The purpose is said to be to smooth the register transition and avoid register breaks. The physiological and acoustical differences between open and covered singing near the so-called passaggio were investigated by means of fiberoptics, inverse filtering, and spectral analysis. The study corroborated previous findings that covering physiologically means a widening and lengthening of the pharynx. Acoustically, covering implies a change of formant frequencies, and an elevated sound pressure level of the lowest source spectrum partial, i.e., the fundamental, resulting from an increased transglottal air flow. The findings indicate that covered singing also is associated with larynx lowering. Covered singing near the passaggio shows similarities to so-called phonation, and is probably preferable from the point of view of vocal hygiene.     

Effect of the thorium oxide content on the leaching of a mixed thorium-uranium oxide fuel

Journal of Radioanalytical and Nuclear Chemistry - Leaching of uranium from uranium oxide fuel in contact with water can be a radiation hazard problem in the case of fuel cladding failure, either...     

A one-to-two-dimensional mapping using a partial Fast Fourier Transform

It will be shown how to map a simple one-dimensional tight binding model with a cosine potential in one dimension exactly to a two-dimensional tight binding model with periodic boundary conditions in the presence of a single flux quantum spread evenly on the torus. The mapping is achieved by a partial sequence of “Fast Fourier Transform” (FFT) steps which if completed would be an exact Fourier transform of the original model. Each step of the FFT recursively maps a tight binding model into two decoupled sublattices of half the lattice length.     

CE to monitor endotoxins by protein complexation

A new CE method for fast and efficient analysis of bacterial endotoxins (lipopolysaccharides) is described. It is based on the strong interaction between proteins and endotoxins. The UV absorption of the protein component in the complex is used for the detection. The electrophoretic mobility of the complex hemoglobin/endotoxin can be employed for qualitative analysis of the endotoxin. For instance, the structural differences between "smooth" and "rough" lipopolysaccharides from Salmonella minnesota (wild-type), Salmonella minnesota R595 and Shigella sonnei R562H are reflected in the electrophoretic mobilities of their hemoglobin complex.     

Universal method for synthesis of artificial gel antibodies by the imprinting approach combined with a unique electrophoresis technique for detection of minute structural differences of proteins, viruses, and cells (bacteria). III: gel antibodies against cells (bacteria)

Artificial antibodies in the form of gel granules were synthesized from the monomers acrylamide and N,N'-methylenebisacrylamide by the imprinting method in the presence of Echerichia coli bacteria as template. The electrophoretic migration velocities of the gel antibodies (i) saturated with the antigen (Escherichia coli MRE-600), (ii) freed of the antigen, and (iii) resaturated with bacteria, were determinated by electrophoresis in a rotating narrow-bore tube of 245 mm length and the 2.5 and 9.6 mm inner and outer diameters, respectively. Removal of bacteria from the gel antibodies was made by treatment with enzymes, followed by washing with SDS and buffer. Gel granules becoming charged by adsorption of bacteria move in an electrical field. We obtained a significant selectivity of gel antibodies for E. coli MRE-600, since the granules did not interact with Lactococcus lactis; and when E. coli BL21 bacteria were added to the gels selective for E. coli MRE-600, a significant difference in the migration rate of the complexes formed with the two strains was observed indicating the ability of differentiation between the two strains. The gel antibodies can be used repeatedly. The new imprinting method for the synthesis of artificial gel antibodies against bioparticles described herein, and the classical electrophoretic analysis technique employed, thus represent - when combined - a new approach to distinguish between different types and strains of bacteria. The application area can certainly be extended to cover other classes of cells.     

Exact transformation for spin-charge separation of spin-1/2 fermions without constraints

We demonstrate an exact local transformation which maps a purely Fermionic many-body system to a system of spinful bosons and spinless fermions, demonstrating a possible path to a non-Fermi-liquid state. We apply this to the half-filled Hubbard model and show how the transformation maps the ordinary spin half Fermionic degrees of freedom exactly and without introducing Hilbert space constraints to a chargelike quasicharge fermion and a spinlike quasispin Boson while preserving all the symmetries of the model. We present approximate solutions with localized charge which emerge naturally from the Hubbard model in this form. Our results strongly suggest that charge tends to remain localized for large values of the Hubbard U.     

Width dependence of the nonadiabatic spin-transfer torque in narrow domain walls

We analytically determine the spatially varying spin-transfer torque within a domain wall. In the case of ballistic spin and diffusive charge transport, the spin-transfer torque as well as the local degree of nonadiabaticity oscillate within a domain wall. In narrow domain walls, the degree of nonadiabaticity ceases to be a constant material parameter but depends on the domain-wall width including a possible sign change, which is crucial for experiments and the technological utilization in spin-transfer-torque-based storage devices.     

A hybrid microdevice for electrophoresis and electrochromatography using UV detection

We have designed a new class of microdevices composed of a supporting plastic (polyvinyl chloride, PVC) plate integrated with a groove for a piece of fused silica capillary (the separation channel), a slit for on-tube detection, an "islet" for the application of sample, electrode vessels and platinum electrodes. The design permits electrophoretic, electrochromatographic and chromatographic separations with on-tube UV detection. The efficient heat dissipation allows relatively high field strengths. This article is the first one dealing with microdevices where polymer solutions are replaced by homogeneous gels. A new type of gels synthesized from acrylamide and 2-hydroxy-3-allyloxy-propyl-beta-cyclodextrin (allyl-beta-CD) as a cross-linker was employed for electrophoresis and electrochromatography. 2-Acrylamido-2-methylpropanesulfonic acid was added to the monomer solution to create a high electroendosmotic flow in electrochromatographic runs. These gels have excellent electrochromatographic and electrophoretic properties for low-molecular-weight compounds and DNA, as shown previously, namely high resolution combined with high stability. The unique cross-linker can be used for specific interaction with the alkyl and phenyl groups. The tripeptide glutathione (gamma-L-glutamyl-L-cysteinyl-glycine) and its benzyl conjugates were selected as model compounds to study the resolving power of the gel because they are difficult to separate by free zone electrophoresis. The limit of detection (LOD) for S-benzyl-glutathione was determined (ca. 7 microM). Run-by-run reproducibility was high (the separation factor of glutathione in the gel was 0.3 with 2.5% coefficient of variation, CV). Neutral compounds (acetone, acetophenone, propiophenone and butyrophenone) were separated electrochromatographically in the gel. The influence of organic solvent (acetonitrile) on the electroendosmotic mobility was similar to that in reversed-phase separations, although the separation mechanism is different. ATP, ADP and AMP were separated in less than 10 s by free-zone electrophoresis.