Rapid crack growth in a thermoelastic solid under mixed-mode thermomechanical loading

A two-dimensional steady-sate analysis of semi-infinite brittlecrack growth at a constant subcritical rate in an unboundedfully-coupled thermoelastic solid under mixed-mode thermomechanicalloading is made. The loading consists of normal and shear tractionsand heat fluxes applied as point sources (line loads in theout-of-plane direction). A related problem is solved exactly in an integral transformspace, and robust asymptotic forms used to reduce the originalproblem to a set of integral equations. The equations are partiallycoupled and exhibit operators of both Cauchy and Abel types,yet can be solved analytically. The temperature change field at a distance from the moving crackedge is then constructed, and its dominant term is found tobe controlled by the imposed heat fluxes. The role of this termis, indeed, enhanced if the heat fluxes serve to render thecrack as a net heat source/sink for the solid, as opposed tobeing a transmitter of heat across its plane. More generally,the influence of the thermoelastic coupling on this field, aswell as other functions, is found to increase with crack speed.     

Synthesis, characterization and application of Ni(tta)2.tmeda to MOCVD of nickel oxide thin films

A novel nickel beta-diketonate adduct, Ni(tta)2.tmeda, has been synthesized using 2-thenoyltrifluoroacetone as the beta-diketonate and N,N,N,'N'-tetramethylethylendiamine as the Lewis base. It has been characterized by elemental analyses, IR, 1H NMR, 13C NMR spectroscopy and single-crystal X-ray diffraction studies. Physical and thermal properties of Ni(tta)2.tmeda precursor have been also extensively investigated. Its efficacy as a metal-organic chemical vapour deposition (MOCVD) precursor for the growth of nickel oxide films has been fully tested by applying it to the deposition of NiO films on quartz substrate. NiO thin films have been characterized by X-ray diffraction (XRD), scanning electron microscopy and UV spectroscopy.     

Synthetic magnetic opals

We present studies of novel nanocomposites of BiNi impregnated into the structure of opals as well as inverse opals. Atomic force microscopy and high resolution elemental analyses show a highly ordered structure and uniform distribution of the BiNi filler in the matrix. These BiNi-based nanocomposites are found to exhibit distinct ferromagnetic-like ordering with transition temperature of about 675 K. As far as we know there exists no report in literature on any BiNi compound which is magnetic.     

A novel diamine adduct of zinc bis(2-thenoyl-trifluoroacetonate) as a promising precursor for MOCVD of zinc oxide films

A novel diamine (N,N,N',N'-tetramethyletilendiamine) adduct of zinc bis(2-thenoyl-trifluoroacetonate) has been synthesized in a single-step reaction. Single-crystal X-ray diffraction studies of Zn(tta)(2).tmeda provide evidence of a mononuclear structure with a six-coordinated zinc ion. The thermal behavior of this adduct points to mass-transport properties suitable for its application to MOCVD processes. This novel compound has been successfully applied as a precursor for the deposition of ZnO films on (100) Si and quartz substrates. The good quality of the deposited films indicates that the adduct is a very attractive precursor for MOCVD applications.     

Synthetic approaches to bridgehead nitrogen methanesulfonamide derivatives of 3‐amino‐2‐thioxo‐2,3‐dihydrothieno[2,3‐d]pyrimidin‐4(1H)‐ones,potential cox‐2 selective inhibitors

Methane sulfonamide derivatives of 3‐amino‐2‐thioxo‐2,3‐dihydrothieno[2,3‐d]pyimidin‐4(1H)‐one, potential selective COX‐2 inhibitors, were synthesized and their structural elucidation is here reported. Some derivatives, at 10 μM concentration, showed a significant percentage of inhibition in some in vitro experiments.     

Copper‐Catalyzed Coupling Reaction of 2‐Thioxo‐4‐quinazolinone and Thieno[3,2‐d]pyrimidin‐4‐one Methane Sulphonamide with Aryl Iodides: Preparation of Potential COX‐2 Selective Inhibitors

Thio‐aryl methane sulfonamide derivatives of 4‐quinazolinone and thieno[2,3‐d]pyrimidin‐4‐one were synthesized using powdery copper/copper(I) iodide as catalyst; their structural elucidation is also reported. These derivatives were planned as sulfur bioisosteres of selective COX‐2 inhibitor drugs.     

Functional neural network analysis in frontotemporal dementia and Alzheimer's disease using EEG and graph theory

Background  

Although a large body of knowledge about both brain structure and function has been gathered over the last decades, we still have a poor understanding of their exact relationship. Graph theory provides a method to study the relation between network structure and function, and its application to neuroscientific data is an emerging research field. We investigated topological changes in large-scale functional brain networks in patients with Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD) by means of graph theoretical analysis of resting-state EEG recordings. EEGs of 20 patients with mild to moderate AD, 15 FTLD patients, and 23 non-demented individuals were recorded in an eyes-closed resting-state. The synchronization likelihood (SL), a measure of functional connectivity, was calculated for each sensor pair in 0.5–4 Hz, 4–8 Hz, 8–10 Hz, 10–13 Hz, 13–30 Hz and 30–45 Hz frequency bands. The resulting connectivity matrices were converted to unweighted graphs, whose structure was characterized with several measures: mean clustering coefficient (local connectivity), characteristic path length (global connectivity) and degree correlation (network 'assortativity'). All results were normalized for network size and compared with random control networks.