The rare boreo-alpine, oligotraphenic diatom Planothidium distinctum (= Achnanthes distincta) was first described from the western Alps in 1954. Achnanthes hirta, a species described in 1970 from the Pyrenees, is regarded as a heterotypic synonym of Planothidium distinctum but almost all morphological details of P. distinctum are known from the type material of Achnanthes hirta. On the basis of...

SUMMARY A number of recent reports concerning the inhibitory action of sulphated polysaccharides on d strains of poliovirus prompted a reinvestigation of the factors involved. It was found that polyglucose compounds in agar are not released in concentrations sufficient to inhibit viruses under the overlay conditionsused for suppressing d strains of poliovirus. Furthermore, sulphated polyanions ...

Choline precursors promote repair and growth of cell membranes and hold promise in a variety of neurologic diseases, including ischemic and hemorrhagic stroke. Citicoline, the most well-studied choline agent precursor, is widely prescribed throughout the world and recently became available in the United States as a dietary supplement. In experimental stroke models, citicoline conferred acute ne...

In man the nitrogen in position 7 is derived from glycine (3). Similar mechanisms are involved in the formation of the nucleic acid guanine in yeast (4) and hypoxanthine in pigeon liver homogenates (5). The earlier demonstration that L-serine is extensively converted to glycine (6) and, presumably, a 1 carbon intermediate provides ground for belief that the P-carbon atom of serine may be a prec...

Non-autoregressive neural machine translation (NAMT) has received increasing attention recently in virtue of its promising acceleration paradigm for fast decoding. However, these splendid speedup gains are at the cost accuracy, comparison to autoregressive counterpart. To close this performance gap, many studies have been conducted achieving a better quality and speed trade-off. In paper, we su...

Improvements in the two-step synthesis of 1,1,1,3,3,3-hexafluoro-2- (fluoromehoxy)propane (Sevoflurane) that result in the product cost reduction, safety level enhancement and positive environmental impacts are described. This process consists of chloromethylation reaction of 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) followed by a halogen-exchange fluorination. This is the first synthesis of Sev...

Improvements in the two-step synthesis of 1,1,1,3,3,3-hexafluoro-2- (fluoromehoxy)propane (Sevoflurane) that result in the product cost reduction, safety level enhancement and positive environmental impacts are described. This process consists of chloromethylation reaction of 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) followed by a halogen-exchange fluorination. This is the first synthesis of Sev...