Pressure Drop for Low Reynolds-Number Flows Through Regular and Random Screens

Creeping flow through both regular and irregular screens was simulated by the lattice-Boltzmann method, and the dependence on screen porosity and Reynolds number of the pressure drop across the screen was analyzed. Regular structures were planar arrays of straight fibers or woven one-layer structures. The irregular planar structures were composed of randomly located and oriented fibers of finite length. A simple function of screen porosity based on partly numerical scaling arguments was found to describe accurately the simulated pressure drop across all regular screens. Due to their bigger surface area, the flow resistance of woven screens was found to be about 15% larger than that of regular planar screens with the same porosity. The pressure drop across irregular planar screens was found to be described by the same screen-porosity function with a slightly different ‘scaling’ exponent which thus appears to be dependent on the structure of the screen. The flow resistance of irregular structures was found to be clearly smaller than that of regular structures because of channelling of the flow through very few largest pores.     

Amberlite IRA-400 Cl resin catalyzed synthesis of secondary amines and transformation into N-((1H-indol-3-yl) (heteroaryl) methyl)-N-heteroaryl benzenamines and bis-indoles via multicomponent reaction

A one-pot Amberlite IRA-400 Cl resin catalyzed the in-situ generation of imines from various aldehydes and primary amines followed by reduction with sodium borohydride affording corresponding secondary amines. The secondary amines thus obtained were utilized for the IRA-400 Cl resin catalyzed multicomponent synthesis of 3-aminoalkylated indoles using a number of aldehydes and indole. Mild condition, easy work-up, and environmentally benign nature of the synthetic strategy make it both practical and attractive.     

Selfconsistent semiclassical calculations using the partial h̵ resummation method

Selfconsistent semiclassical calculations using the partial resummation technique have been performed for a number of spherical nuclei. The results are found in very good agreement with those obtained in the more lengthy selfconsistently Strutinsky averaged Hartree-Fock approach. Our method has also been applied to the determination of liquid drop parameters associated with effective forces of the Skyrme type.     

Collective gyromagnetic ratio and moment of inertia from density-dependent Hartree-Fock calculations

The collective gyromagnetic ratio and moment of inertia of deformed even-even axially symmetric nuclei are calculated in the cranking approximation using wave functions obtained with the Skyrme force S-III. Good agreement is found for g_R, while the moment of inertia is about 20 % too small. The cranking formula leads to better agreement than the projection method.     

Covalent grafting of fibronectin onto plasma-treated PTFE: influence of the conjugation strategy on fibronectin biological activity

Surface coating of synthetic materials is often considered to improve biomedical devices biocompatibility. In this study, we covalently bound fibronectin (FN) onto ammonia plasma-treated PTFE via two crosslinkers, namely glutaric anhydride (GA) and sulfosuccinimidyl-4-(p-maleimidophenyl)butyrate (sulfo-SMPB). With respect to clean PTFE, cell adhesion increased markedly on both FN grafted surfaces, although it was twice higher on PTFE-GA-FN than on PTFE-SMPB-FN. ELISA experiments performed with a polyclonal antibody revealed that the amount of FN is identical on both surfaces while monoclonal antibody specific to the RGD binding site clearly demonstrated a greater availability when FN is surface grafted through GA. These results provide evidence of a variation in protein conformation correlated with the surface conjugation strategy.     

Evaluation of the suitability of archival Bouin-fixed paraffin-embedded tissue specimens to proteomic investigation

Bouin's solution has been used for over a century as a common fixative in several pathology laboratories worldwide. Therefore, a considerable number of Bouin-fixed paraffin-embedded (BFPE) tumor samples of various origin are available in hospital repositories as a powerful information mine for clinical investigations. To date, however, such archived tissues have not been subjected to a systematic study aimed to evaluate their potential use in proteomics. In this report, we investigated whether archival BFPE tissue specimens could be exploited for proteomic studies, upon application of protein extraction and proteomic analysis methods previously optimized for formalin-fixed samples. As a result, gastric BFPE protein extracts exhibited poor suitability for 2D-PAGE analysis, whereas over 300 unique proteins could be successfully detected when extracts were subjected to SDS-PAGE followed by LC-MS/MS (GeLC-MS/MS). Among these, several known markers for gastric cancer and normal gastric functionality were identified, indicative of biological and clinical significance of proteomic data mined from BFPE tissues. A quantitative and qualitative comparison of FFPE and BFPE tissue proteomes was also performed, and results are reported. In conclusion, we demonstrated that BFPE specimens can be analyzed by means of a proteomic approach such as GeLC-MS/MS. Although considerable molecular biases and technical constraints exist, BFPE tissue archives can be fruitfully exploited for gathering proteomic data from particularly precious samples.     

Synthesis and spectral studies of copper(II), nickel(II), cobalt(II) and vanadyl(II) complexes of tridentate Schiff bases of 1,2,3,5,6,7,8,8a-octahydro-3-oxo-N,1-diphenyl-5-(phenylmethylene)-2-naphthalenecarboxamide

Summary Metal(II) chelates of Schiff bases derived from the condensation of 1,2,3,5,6,7,8,8a-octahydro-3-oxo-N,1-diphenyl-5-(phenylmethylene)-2-naphthalenecarboxamide with o-aminophenol (KAAP), o-aminothiophenol (KAAT) or o-aminobenzoic acid (KAAB) have been prepared and characterized. The complexes are of the type [M(N₂X)]₂ for M = Cu^II and M(NX)₂·nH₂O for M = Ni^II, Co^II and VO^II (X = phenolic oxygen, thiophenolic sulphur or carboxylic oxygen; n = 0 or 2). Conductivity data indicate that the complexes are non-ionic. The Schiff bases behave as dibasic tridentate ligands in their copper(II) complexes and as monobasic bidentate ligands in their nickel(II), cobalt(II) and vanadyl(II) complexes. The subnormal magnetic moments of the copper(II) complexes are ascribed to an antiferromagnetic exchange interaction arising from dimerization. Nickel(II) and cobalt(II) complexes are trans octahedral whereas vanadyl(II) complexes are square pyramidal