No abstract

Eco-friendly solid-contact ion selective electrode was fabricated and optimized for the determination of flavoxate hydrochloride in presence of its main metabolite. The process is based on carbon screen printed electrode and polyvinyl chloride polymeric sensing membrane. The first optimization step involved the ionophore selection through screening various ionophores, where calix[4]arene showed the highest affinity towards flavoxate. The second step, a graphene nanocomposite interlayer was employed as the ion-to-electron transducer between the carbon electrode and the polymeric ion sensing membrane. The graphene layer decreased the potential drift down to < 500 μV/h and improved the electrode stability.

1. An analysis has been made of milk records from 3109 cattle of the six main dairy breeds in England and Wales.2. The correlation between measurements on separate lactations declined as the time interval between the lactations increased. The average correlation was 0·38 for 70 days' milk yield and 0·48 and 0·55 respectively for milk yield and fat content in the 305-day lactation.3. The heritabilities of the three measurements measured by daughter-dam regression were found for heifer lactations to be 0·36, 0·43 and 0·43 respectively. On second lactations, they were 0·09, 0·24 and 0·42.4. As a consequence of the low heritability of the second lactation yield, the average yield of the first four lactations proved to have no more value as a prediction of a cow's breeding merit for yield than did her heifer yield.5. In agreement with other workers, we found that 70-days yield was an excellent guide to the total lactation (r ~ 0·80), and that it could be used as a guide to early selection.6. There was some indication that the correlation between yield and fat content in the same lactation was more strongly negative in heifers and in the Channel Island breeds. The overall genetic correlation on first lactations was found to be − 0·66 ± 0·20, rather more strongly negative than has been found previously.

No abstract

No abstract