丙烯酰胺-丙烯酸-丙烯羟肟酸共聚物乳液脱除电镀废水中的重金属离子

采用反相乳液聚合法合成了丙烯酰胺(AM)-丙烯酸(AA)- 丙烯羟肟酸(AHA)共聚物乳液。考察了该共聚物配方中丙烯羟肟酸用量、共聚物乳液的投量和pH值对电镀废水中重金属离子的脱除效果。结果表明：pH=10,丙烯羟肟酸在共聚物乳液中的用量≥15%,共聚物乳液的投量为20～30 mg/L时,脱除电镀废水中重金属离子的效果最好,Cr、Cu、Ni和Zn等重金属离子的脱去率≥99.5%,处理后的水中每种重金属离子浓度≤0.2 mg/L。     

Crk protein binds to PDGF receptor and insulin receptor substrate-1 with different modulating effects on PDGF- and insulin-dependent signaling pathways

We have studied the involvement of murine c-Crk, an SH2/SH3 containing adaptor protein, in signaling pathways stimulated by different receptor tyrosine kinases. We show here that c-Crk is associated with components of insulin- and PDGF-dependent signaling pathways. Insulin treatment of murine myoblast cells induces the formation of stable complex of endogenous c-Crk with insulin receptor substrate-1 (IRS-1) mediated via the SH2 domain of Crk. The ligand dependent physical association of c-Crk with IRS-1 is direct. However IRS-1 is also co-precipitated with c-Crk from quiescent L6 cells. The association of IRS-1 with c-Crk in quiescent cells is probably not direct since Far Western blot analysis did not reveal the binding of neither SH2 domain nor amino-terminal SH3 domain of c-Crk to IRS-1 from unstimulated cells. We also show that PDGF treatment of murine myoblast cells induces association of c-Crk with the PDGF receptor and tyrosine phosphorylation of c-Crk. Overexpression of c-Crk enhanced insulin- but not PDGF-induced activation of MAP kinases when compared to parental cell lines. Thus, the formation of the direct IRS-1/Crk complex appears to be crucial for Crk-mediated insulin-induced activation of MAP kinase, whereas Crk is probably involved in other PDGF-induced responses. These data provide support to the hypothesis that insulin and PDGF employ different mechanisms for activation of MAP kinase cascade.     

The interaction of homogeneous motor conditioned reflexes during conditioned-reflex switchover: the transfer of learning and interference

The dynamics of elaboration of the conditioned switchover (CSw) of homogeneous motor conditioned reflexes (CR) with different lateralization of the motor skill was studied in rabbits. Learning of CSw was shown to pass three basic stages characterized by different degree of consolidation of the CRs, by interaction between the two CRs, and by manifestation of CSw. Stages I and II reflected the process of afferent and efferent generalization of CRs and CSw, stage III was associated with specialization of CRs and CSw. Both positive and negative transfer of motor learning as well as interference between the two motor skills took place during CSw elaboration. The highest rate of CSw acquisition was observed in rabbits displaying positive motor transfer.     

Degradation of Bisoprolol Fumarate in Tablets Formulated with Dicalcium Phosphate

Degradation of Bisoprolol Fumarate in tablet dosage forms was accelerated when granular Dicalcium Phosphate Anhydrous USP was substituted for milled Dicalcium Phosphate Anhydrous USP. Studies demonstrate that instability with the granular material is due to an acidic microenvironment created by this material in the presence of moisture. Bisoprolol is less stable at this low pH compared to a neutral microenvironmental pH which is created with milled Dicalcium Phosphate Anhydrous.     

Rossi-α measurement of the effective delayed-neutron fraction

Main Scientific Center of the Russian Federation — Physics and Power Engineering Institute. Translated from Atomnaya énergiya, Vol. 78, No. 3, pp. 152–155, March, 1995.