Newly synthesized rifamycin derivatives, KRM-1648, KRM-1657, KRM-1668, KRM-1686, and KRM-1687, having the chemical structures of 3'-hydroxy-5'-(4-alkylpiperazinyl)-benzoxazinorifamycins (alkyl residues: isobutyl, propyl, sec-butyl, sec-butyl [R configuration], and sec-butyl [S configuration], respectively), were studied for their in vitro antimycobacterial activities. Representative (KRM-1648) ...

The observed abrupt torque reversals in X-ray pulsars, 4U 1626-67, GX 1+4, and OAO 1657-415, can be explained by transition in accretion flow rotation from Keplerian to sub-Keplerian, which takes place at a critical accretion rate, ∼ 10 − 10g/s. When a pulsar system spins up near equilibrium spin before the transition, the system goes into spin-down after transition to sub-Keplerian. If a syste...

discrete areas of knowledge were in the sixteenth and seventeenth century closely related and interacting. Whether dealing with the anatomist Harvey, the physician Dalechamps, the astronomer Galileo, or the philosopher Zabarella, Schmitt was always aware of the wider context, and his insights into one speciality often illuminated another. As Charles Webster points out in his introduction, these...

in this research, process asymmetric polyetherimide hollow fiber membranes using ethanol (0, 2 and 4 wt%) as non-solvent additive in the polymer dope via phase inversion method were fabricated. aqueous solution of 1-methyl-2-pyrrolidine (nmp) (90%) was applied as a bore fluid to avoid inner skin layer formation and water was used as the external coagulant. the morphology of fabricated membranes...

carbon molecular sieve membranes (cmsms) have been considered as very promising candidates for gas separation, in terms of separation properties as well as thermal and chemical stability. due to the numerous advantages and wide applications of carbon membranes, their application for gas separation is of special importance. because of the importance of carbon membranes and a large number of stud...

results the mean kt/v was 1.27 ± 0.28 in high-flux and 1.10 ± 0.32 in low-flux membrane which, these differences were statistically significant (p = 0.017). the mean of urr was 0.65 ± 0.09 in high-flux and 0.61 ± 0.14 in low-flux membrane, which these differences were not statistically significant (p = 0.221). patients and methods forty hemodialysis patients participated in this cross-over clin...

heterogeneous proton exchange membranes (pem) are synthesized using the dry phase inversion technique. the casting solutions are prepared by dispersing a finely ground cation exchange resin particle in n,n-dimethylacetamide (dmac) solution of polyvinyl-chloride (pvc). results show that ion exchange capacity is increased with the addition of 1 %-wt nanosilica (from 0.14 to 0.27 meq/g) while it i...