Spectral pattern of total creatine and trimethyl ammonium in multiple sclerosis

Fatigue and impairment mobility are frequent problems in multiple sclerosis (MS). Despite its enormous potential, in vivo (1)H MRS of skeletal muscles for MS patients is a largely unexplored field. One fundamental question remains unanswered: whether MS can cause observable proton metabolite changes. High quality two-dimensional in vivo (1)H MRS reveals that the spectral pattern of total creatine (tCr) and trimethyl ammonium (TMA) of soleus muscles of MS patients can be distinctively different from that of healthy volunteers, and in vivo (1)H MRS of skeletal muscles has a potential to become a useful tool in MS study.     

Group algebras with symmetric units satisfying a group identity

We study group algebras FG for which the symmetric units under the natural involution: g^*=g⁻¹ satisfy a group identity. For infinite fields F of characteristic ≠2, a classification of torsion groups G whose symmetric units U⁺(FG) satisfy a group identity was given in [3] by Giambruno-Sehgal-Valenti. We extend this work to non torsion groups. Research supported by NSERC of Canada and MIUR of Italy.     

Central units of integral group rings of nilpotent groups

In this paper a finite set of generators is given for a subgroup of finite index in the group of central units of the integral group ring of a finitely generated nilpotent group.

     

Microwave absorption studies of MgB2 superconductor

Microwave absorption studies have been carried out on MgB₂ superconductor using a standard X-band EPR spectrometer. The modulated low-field microwave absorption signals recorded for polycrystalline (grain size ∼ 10 μm) samples suggested the absence of weak-link character. The field dependent direct microwave absorption has been found to obey a ✓H dependence with two different slopes, which indicated a transition from strongly pinned lattice to flux flow regime.     

Laser excited Raman spectra of Gr. VI semiconducting compounds

Raman spectra of hexagonal layer compounds MoS₂, MoSe₂ and MoTe₂ were excited by a HeNe laser (6328Å). All the Raman active long-wave-length phonon frequencies were determined. These are A_1g, E¹_2g, E_1g and E²_g. The frequencies decrease as we pass from sulphur to tellurium and the quasiacoustical mode E²_2g has the lowest frequency. A comparison of the results with infrared spectra shows that the i.r. active mode for E ⊥ C is degenerate with one of the Raman active modes in the basal plane for all the compounds.     

Characterization of keratin–collagen 3D scaffold for biomedical applications

Fabrication of keratin–collagen (KC) 3D scaffold with improved thermal denaturation rate is reported. In vitro application of (KC) scaffold stimulates basic extra cellular matrix constituents. KC Scaffold considerably reduced undesirable properties of both collagen and keratin while collagen incorporation reduces the fragility with increases of strength and flexibility in the scaffold. In addition to this, the scaffold showed homogenous well‐interconnected pores in the range of 10–100 µm when observed in scanning electron microscope. Usage of keratin in KC scaffold offers increased biodegradation rate and higher denaturation rate in addition to its rapid cell growth with normal morphology ultimately reaching cell population of 3.9–9.7 million per cm³ after 48 hr in KC scaffold. Circular dichroism (CD) and Fourier transform spectroscopy (FT‐IR) of KC showed presence of helical structure of collagen and ß‐turns of keratin confirming retention of native structures of both the proteins KC scaffold showed good swelling behavior and water uptake. Our study strongly supports the superidity of KC scaffold over the collagen or keratin when they are independently used for tissue engineering applications. Copyright © 2011 John Wiley & Sons, Ltd.