Júlia Singer

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Ventral lateral hypothalamic lesions, made before electrical stimulation, blocked the acquisition of a preference for alcohol by rats; but dorsal lateral hypothalamic lesions did not alter their alcohol consumption. Rats offered alcohol on alternate days, without stimulation, increased their alcohol intake but did not develop a stable preference for alcohol.
This paper contains a short generalization of a known method for sample size determination in the case of more than two parallel groups. The term 'set of allocation ratios' corresponding to the allocation ratio from the two-group design is defined. A formula using these ratios to determine the non-centrality parameter of the F distribution is deduced. It is(More)
The influence of molecular structure on the mechanical properties of self-assembled 1,3,5-benzenetrisamide nanofibers is investigated. Three compounds with different amide connectivity and different alkyl substituents are compared. All the trisamides form well-defined fibers and exhibit significant differences in diameters of up to one order of magnitude.(More)
The usual methods of sample size determination which assume the homogeneity of within-group variances are not sufficiently robust against the violation of this assumption. A method using Satterthwaite's correction for unequal variances is given. It is shown that in the case of unequal variances the minimum total sample size is attained when the allocation(More)
A single-dose, "crossover" bioequivalence study was conducted in healthy volunteers by comparing sulpiride serum levels after oral administration of the Test Product Sulpiride (200 mg) (GYKI-Alkaloida) in fasting subjects with those produced after oral administration of a marketed reference product (200 mg) (Delagrange Co., France). Statistical comparisons(More)
Two diagnostic procedures with binary outcomes are usually compared by Cohen's kappa coefficient of agreement. If the results of the two procedures are completely identical on a sample and so kappa equals to 1, the precision of the estimate can not be computed with the usual formulae and statistical softwares. A formula for variance which is valid in this(More)