Sobolev embeddings for Riesz potential spaces of variable exponents near 1 and Sobolev's exponent

Our aim in this paper is to deal with Sobolev embeddings for Riesz potentials of order α for functions f satisfying the Orlicz type condition

     

Effects of meals on gastric emptying and small intestinal transit times of a suspension in the beagle dog assessed using acetaminophen and salicylazosulfapyridine as markers

Effects of the amount and the composition of meals on gastric emptying and small intestinal transit times of a suspension were investigated in beagle dogs using acetaminophen and salicylazosulfapyridine as markers. Gastric emptying time was affected both by the amount and the composition of a meal; it was prolonged proportionally to the amount of a solid meal and varied among the 3 kinds of test meals of the same energy content in the following rank order: lard greater than skimmed milk greater than mashed potatoes. The inter-individual variation of small intestinal transit time in a fed state was smaller than that in a fasted state, whereas the mean transit times in both states were similar. Small intestinal transit time was not affected by the amount of the solid meal. On the other hand, it varied among the 3 kinds of test meals in the following rank order: lard greater than mashed potatoes greater than skimmed milk. It is noteworthy that small intestinal transit time in the beagle dog is approximately 2 h shorter than that in humans both in fasted and fed states.     

Tomato new sapogenols, isoesculeogenin A and esculeogenin B

Two novel sapogenols, isoesculeogenin A (1) and esculeogenin B (2) of steroidal alkaloid glycosides, lycoperoside F and esculeoside B, respectively, isolated from the ripe tomato have been characterized as (5alpha,22R,23R,25S)-3beta,23,27-trihydroxyspirosolane and (5alpha,22S,23R,25S)-22,26-epimino-16beta,23-epoxy-3beta,23,27-trihydroxycholestane, respectively.     

Radical polymerization of alkyl crotonates as 1,2-disubstituted ethylenes leading to thermally stable substituted polymethylene

Radical polymerization of several alkyl crotonates (RCr) was carried out in bulk or in benzene in the presence of radical initiators. Homopolymerization of RCr bearing bulky ester alkyl groups, e.g. tert-butyl (tBCr), 1-adamantyl (AdCr), and 3,5-dimethyl-1-adamantyl crotonate (DMAdCr) proceeded to give a polymer with molecular weight of several thousands despite of the steric hindrance and chain transfer by the presence of the β-methyl group, while the methyl and ethyl esters gave no polymer. The kinetics of the polymerization was examined in detail and absolute rate constants were evaluated by means of electron spin resonance spectroscopy. The propagation rate constants of RCr were 0.41–1.0 L/mol s, being much smaller than those of the corresponding methacrylates (530–570 L/mol s). The termination rate constants were also determined from the analyses of steady state and non-steady state polymerizations. Radical copolymerizations of AdCr (M₂) with several vinyl monomers (M₁) were carried out in bulk at 60°C and the rate constants for cross propagations were calculated to examine reactivities of the monomer and its polymer radical. The structure and thermal properties of the resulting poly (AdCr) were also investigated. Onset temperature of decomposition and glass transition temperature of poly(AdCr) were revealed to be much high as 302 and 234°C, respectively. © 1994 John Wiley & Sons, Inc.     

Preparation of 1-hydroxyethyl-2-trideuteriomethyl-5-nitroimidazole

The title compound was prepared by two different procedures. The first route starts with acetonitrile-d₃ and goes through 2-trideuteriomethyl-5-nitroimidazole ( 6 ) (Scheme I). The second and more convenient process is direct labeling of metronidazole ( 1 ) with alkaline ethanol-d₁.     

The preparation of di- and tri-phenylstannyl esters of aromatic dithio acids,and some of their reactions

Some crystalline di- and tri-phenylstannyl esters [ArCS₂SnPh₃ and (ArCS₂)₂SnPh₂] of aromatic dithio acids have been prepared in good yields and characterized. Preferential cleavage of the SnS bond of the ester was observed by treating them with primary and secondary amines as well as with phenacylidenetetramethylenesulfurane.     

Synthesis and properties of a pyrrole-imidazole polyamide having a ferrocene dicarboxylic amide linker

A new minor groove binder 1 having a redox active ferrocene dicarboxamide linker was synthesized. The affinity of the newly synthesized compound to the target DNA was confirmed by CD titration experiments. Moreover, the redox property of 1 was also demonstrated by cyclic voltammetry. These results suggest the potential of 1 as a new tool for electrochemical gene detection technology.