Thermal,spectral and morphological studies on cellulose,cellulose ethylthiophosphate and its metal complexes in air

Metal complexes of thiophosphorylated cellulose, when heated, give rise to high char yields. These and related observations suggest that such derivatisation may give rise to novel flame retardant treatments for cellulosic materials. The kinetics of thermal degradation of cellulose, cellulose ethylthiophosphate (CESP) and metal complexes of the CESP have been studied by thermogravimetry (TG) and differential thermal analysis (DTA) from ambient temperature to 700°C in dynamic air to investigate the potential flame retardance of the CESP and its metal complexes. Various parameters such as energy, entropy, enthalpy and free energy of activation have been calculated using the Broido method and transition state theory. For the decomposition stage of thermal degradation, the activation energies of the CESP samples lie in the range 53-133 kJmol^?1 and of the metal complexes, 108-177kJmol^?1, which are found to be lower than that of cellulose (187 kJmol^?1). Scanning electron micrographs of the CESP show that the fibrillar structure of cotton has become more evident and chars retain the general morphology of the original fibre although severe, localised zones of damage reflect the gross chemical and physical changes occurring during pyrolysis. The IR spectra of chars of modified samples indicate formation of compounds containing C=O, C=C and P=O groups. The mechanisms of thermal degradation of the CESP and its metal complexes have been proposed.     

Finite element method in magnetohydrodynamic channel flow problems

The finite element method has been applied to the steady-state fully developed magnetohydrodynamic channel flow of a conducting fluid in the presence of transverse magnetic field. Simple elements have been used to obtain the numerical values of velocity and induced magnetic field. To test the efficiency of the method, three different geometries, viz., rectangle, circle and triangle, are taken as the section of the pipe whose walls are non-conducting. Comparison is made with those cases in which exact solutions are available. Apart from giving good results, the FEM makes it possible to solve the problem for a pipe with arbitrary cross-section which was not possible by the other methods.     

In vitro anthelmintic action of some indigenous medicinal plants on Ascardia galli worms

Different parts of ten indigenous medicinal plants were screened for their in vitro anthelmintic activity against Ascaridia galli worms of the birds. Preparations from Carica papaya, Sapindus trifoliatus, Butea frondosa and Momordica charantia were more effective than piperazine hexahydrate.     

Über die Basizität flüssiger Schlacken der Systeme CaO–SiO2 und CaO–Al2O3

EMK-Messungen mit einer Diffusionszelle an flüssigen Schlacken der Systeme CaO–Al₂O₃ und CaO–SiO₂ bei 1600°C. EMK und Sulfidkapazität zeigen lineare Abhängigkeit. EMK-Werte können als relatives Basizitätsmaß gewertet werden.     

Enhanced specificity of truncated transmembrane protein for serologic confirmation of human T-cell lymphotropic virus type 1 (HTLV-1) and HTLV-2 infections by western blot (immunoblot) assay containing recombinant envelope glycoproteins

Immunoassays based on the highly immunogenic transmembrane protein of human T-cell lymphotropic virus type 1 (HTLV-1) (protein 21c) are capable of detecting antibodies in all individuals infected with HTLV-1 and HTLV-2. However, because of antigenic mimicry with other cellular and viral proteins, such assays also have a large proportion of false-positive reactions. We have recently identified an immunodominant epitope, designated GD21-I located within amino acids 361 to 404 of the transmembrane protein, that appears to eliminate such false positivity. This recombinant GD21-I protein was used in conjunction with additional recombinant HTLV type-specific proteins and a whole virus lysate to develop a modified Western blot (immunoblot) assay (HTLV WB 2.4). The sensitivity and specificity of this assay were evaluated with 352 specimens whose infection status was determined by PCR assay for the presence or absence of HTLV-1/2 proviral sequences. All HTLV-1-positive (n = 102) and HTLV-2-positive (n = 107) specimens reacted with GD21-1 in the HTLV WB 2.4 assay, yielding a test sensitivity of 100%. Furthermore, all specimens derived from individuals infected with different viral subtypes of HTLV-1 (Cosmopolitan, Japanese, and Melanesian) and HTLV-2 (IIa0, a3, a4, IIb1, b4, and b5) reacted with GD21-I in the HTLV WB 2.4 assay. More importantly, HTLV WB 2.4 analysis of 81 PCR-negative specimens, all of which reacted to recombinant protein 21e in the presence or absence of p24 and p19 reactivity in the standard WB assay, showed that only two specimens retained reactivity to GD21-I, yielding an improved test specificity for the transmembrane protein of 97.5%. None of 41 specimens with gag reactivity only or 21 HTLV-negative specimens demonstrated reactivity to GD21-I. In an analysis of additional specimens (n = 169) from different geographic areas for which PCR results were not available, a substantial increase in the specificity of GD21-I detection was demonstrated, with no effect on the sensitivity of GD21-I detection among specimens from seropositive donors. Thus, the highly sensitive, GD21-I-based HTLV WB 2.4 assay eliminates the majority of false-positive transmembrane results, thereby increasing the specificity for serologic confirmation of HTLV-1 and HTLV-2 infections.     

Acute coronary occlusion during early post-PTCA exercise testing: a rare but avoidable risk

We describe here one instance of an acute occlusion of an angioplastied LAD coronary artery occurring during a treadmill stress test performed 2 d after the procedure. The occlusion occurred during the recovery period after a reasonably high level of stress was achieved without evidence of ischaemia. Similar instances described in the literature are summarized and discussed. In the light of these data, it might be prudent to avoid early post-PTCA exercise stress testing.     

Interocepttve Stimuli as Tools of Drug Development

Tools of Drug Development

Drug development is the foremost objective of most pharmacologists in the pharmaceutical companies and some pharmacologists in the other research institutions. To meet this objective, thousands of new chemical compounds must be evaluated in order to discover one which can be safely employed in the treatment of human illness. Such evaluation requires an enormous number of experimental subjects specially prepared for this purpose. Since use of human patients for initial screening of new chemicals is not feasible one must depend on laboratory animals that can be used repeatedly and extensively.