The splicing of group II introns occurs in two steps involving substrates with different chemical configurations. The question of whether these two steps are catalyzed by a single or two separate active sites is a matter of debate. Here, certain bases and phosphate oxygen atoms at conserved positions in domain V of a group II self-splicing intron are shown to be required for catalysis of both s...

Three group A arboviruses, Sindbis (SIN), western (WEE) and eastern equine encephalitis (EEE), were selectively degraded with a nonionic detergent to yield a core particle and a soluble envelope component. Antigenic analysis by using radioimmune precipitation techniques revealed marked antigenic similarity among the core particles of the three viruses. The soluble envelope component exhibited a...

many students are being faced to some problems in instructive skills such as reading and comprehension especially when they study literary texts, [1]both in school and university. to solve this problem, such skills should [2]be taught with a method that the learner(s) has an active relation to the text and its components. he (she) should be able to make a connection between the text and his (he...

We take a process component as a pair of an interface and a behaviour. We study the composition of interacting process components in the setting of process algebra. We formalize the interfaces of interacting process components by means of an interface group. An interesting feature of the interface group is that it allows for distinguishing between expectations and promises in interfaces of proc...

OBJECTIVE To standardise a complex intervention by defining the characteristic (specific) components of treatment for a randomised controlled trial of acupuncture as an intervention for individuals who have been diagnosed with depression using a consensus method. METHODS A nominal group technique was used. Potential components of the acupuncture intervention were generated from the literature...

Silica boron sulfonic acid [SiO2–B(OSO3H)3] as an inexpensive, reusable, and Lewis and Brønsted acid catalyst was successfully synthesized, and used for the one-pot three-components synthesis of biologically active substituted Hantzsch 1,4-dihydropyridine derivatives  in the absence of solvent at 90ºC. Silica boron sulfonic acid is attractive and efficient, because it plays in two role as a Lew...

‎In this paper‎, ‎a coherent system consisting of non-identical dependent active components and‎ ‎equipped with non-identical dependent standby components is considered‎. ‎The main object of this study is the random quantity‎ ‎which account the number of surviving standby components when the system‎ ‎is failed‎. ‎We represent the distribution function of the corresponding random variable in ter...

It is well known that the [O ]λ5007 emission line and hard X-ray(2-10keV) luminosities are good indicators of AGN activities and that the near and mid-infrared emission of AGN originates from re-radiation of dusty clouds heated by the UV/optical radiation from the accretion disk. In this paper we present a study of the near-infrared K-band (2.2μm) properties for a sample of 65 Seyfert 2 gala...