DNA vaccine containing the mycobacterial hsp65 gene prevented insulitis in MLD-STZ diabetes

Background  

Our group previously demonstrated that a DNA plasmid encoding the mycobacterial 65-kDa heat shock protein (DNA-HSP65) displayed prophylactic and therapeutic effect in a mice model for tuberculosis. This protection was attributed to induction of a strong cellular immunity against HSP65. As specific immunity to HSP60 family has been detected in arthritis, multiple sclerosis and diabetes, the vaccination procedure with DNA-HSP65 could induce a cross-reactive immune response that could trigger or worsen these autoimmune diseases.     

Wave attenuation model for dephasing and measurement of conditional times

Inelastic scattering induces dephasing in mesoscopic systems. An analysis of previous models to simulate inelastic scattering in such systems is presented and a relatively new model based on wave attenuation is introduced. The problem of Aharonov-Bohm (AB) oscillations in conductance of a mesoscopic ring is studied. We show that the conductance is symmetric under flux reversal and the visibility of AB oscillations decays to zero as a function of the incoherence parameter, signaling dephasing. Further the wave attenuation model is applied to a fundamental problem in quantum mechanics, that of the conditional (reflection/transmission) times spent in a given region of space by a quantum particle before scattering off from that region.     

Qualitative properties of modified equations

Suppose that a consistent one-step numerical method of orderr is applied to a smooth system of ordinary differential equations.Given any integer m 1, the method may be shown to be of orderr + m as an approximation to a certain modified equation. Ifthe method and the system have a particular qualitative propertythen it is important to determine whether the modified equationsinherit this property. In this article, a technique is introducedfor proving that the modified equations inherit qualitativeproperties from the method and the underlying system. The techniqueuses a straightforward contradiction argument applicable toarbitrary one-step methods and does not rely on the detailedstructure of associated power series expansions. Hence the conclusionsapply, but are not restricted, to the case of Runge-Kutte methods.The new approach unifies and extends results of this type thathave been derived by other means: results are presented forintegral preservation, reversibility, inheritance of fixed points.Hamiltonian problems and volume preservation. The techniquealso applies when the system has an integral that the methodpreserves not exactly, but to order greater than r. Finally,a negative result is obtained by considering a gradient systemand gradient numerical method possessing a global property thatis not shared by the associated modified equations.     

How Fast can a Subharmonic Function Decay Along a Ray?

Much is known about the connection between the growth and decayof subharmonic functions. The results indicate that there isa general principle: asubharmonic function cannot decay ‘toofast’ relative to its growth.Three theorems are provedwhich, together with work previously published elsewhere, givea fairly complete account of how this principle works out fora subharmonic function having extremal decay along a ray. 1991Mathematics Subject Classification: 30D20, 31A05.     

Efficient nanoparticle focusing utilizing cascade AC electroosmotic flow

This study presents on-chip continuous accumulation and concentration of nanoscale samples using a cascade alternating current electroosmosis (cACEO) flow. ACEO can generate flow motion caused by ion movement due to interactions between the AC electric field and the induced charge layer on the electrode surface, with the potential to accumulate particles, especially in low-conductive liquid. However, the intrinsic particle diffusive motion, which is sensitive to particle size, is an essential element influencing accumulation efficiency. In this study, an electrode combining chevron and double-gap geometry embedded in a microfluidic channel was developed to perform efficient three-dimensional (3D) nanoparticle focusing using ACEO. The chevron electrode pattern was introduced upstream of the focusing zone to overcome particle accumulation in scattering zones near the channel sidewall. To demonstrate the efficiency of the proposed device for particle accumulation, three nanoparticle types were used: latex, metal, and biomaterial. Continuous 3D concentration of 50-nm polystyrene particles was confirmed. The concentration factor, determined based on image processing, became quite high when 50-nm gold nanoparticles were used. Moreover, nanoparticles with a 20-nm diameter were accumulated using cACEO. Finally, we used the concentrator chip to accumulate 50-nm liposome particles, confirming that the device could also successfully concentrate biomaterials.     

Solid-phase extraction of Cu2+ and Pb2+ from waters using new thermally treated chitosan/polyacrylamide thin films; adsorption kinetics and thermodynamics

New biologically safe thin adsorptive films were synthesised using chitosan/polyacrylamide polymer blend (Ch/PA) via thermal crosslinking technique for the separation of Cu²⁺ and Pb²⁺ from aqueous solution and natural water samples. The prepared films were characterised using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and Thermogravimetric analysis (TGA) techniques. Thermo-gravimetric analysis revealed an enhancement in the thermal stability of the prepared thin films with increasing polyacrylamide content. Kinetic and thermodynamic studies were evaluated by batch-type experiments. The obtained results indicated that the adsorption isotherms were well described by Freundlich model, and Ch/PA have adsorption capacities of 177.9 and 126.58 mg.g^?1 to Cu²⁺ and Pb²⁺, respectively. Under optimum conditions, calculated detection limits were as low as 0.018 and 0.034 μg.L^?1 for Cu²⁺ and Pb²⁺, respectively, and relative standard deviations of less than 4% for five separate experiments. Moreover, the traditional Lagergren adsorption kinetic model provided the best fitting for the kinetic data. Furthermore, the reusability studies revealed a decrease in the adsorption capacity by about 8% after three adsorption–desorption cycles. The prepared thin films were successfully applied for the separation of Cu²⁺ and Pb²⁺ from natural water samples.