Informational energy test for equality of variances

On the basis of the informational energy an alternative test of homogeneity of variances in samples from normal populations is developed. In addition, several of the more well known statistics for performing this type of analysis and the new test proposed here are compared in a Monte Carlo stud

Efeito da concentração espermática e do número de inseminações artificiais sobre a fertilidade de éguas inseminadas com sêmen fresco diluído Effects of sperm concentration and number of artificial inseminations on fertility of inseminated mares with diluted fresh semen

Sessenta e duas fêmeas eqüinas (tipo militar) foram distribuídas, ao acaso, em dois grupos experimentais para estudar o efeito da concentração espermática (200× 10(6) e 400× 10(6) de espermatozóides progressivamente móveis/dose inseminante) e do número de inseminações/ciclo (duas, três e quatro ou mais inseminações) sobre a fertilidade. As éguas foram rufiadas e inseminadas às segundas, quartas e sextas-feiras, a partir de um folículo de 3,0 a 3,5cm de diâmetro, com sêmen de apenas um garanhão com fertilidade comprovada, diluído para um volume inseminante de 10ml com diluidor de mínima contaminação. As taxas de concepção ao primeiro ciclo para as concentrações de 200 e 400 milhões foram de 66,7% (20/30) e 65,5% (19/29), e as taxas de concepção/ciclo, após quatro ciclos, de 52,0% (26/50) e 57,8% (26/45), respectivamente (P>0,05). As taxas de concepção ao primeiro ciclo para os grupos com duas, três e quatro ou mais inseminações/ciclo foram, respectivamente, 72,0% (18/25), 65,2% (15/23) e 54,6% (6/11), sem que se observassem diferenças entre elas (P>0,05). Após quatro ciclos, as taxas de concepção foram de 59,0% (23/39), 52,5% (21/40) e 50,0% (8/16), respectivamente, na mesma ordem de citação (P>0,05). Com base nos resultados, recomendam-se inseminações às segundas, quartas e sextas-feiras, utilizando-se a concentração de 200×10(6) SPTZ/dose inseminante, sem que haja perda da fertilidade, independente do número de inseminações/ciclo.<br>This work aimed to study the effects of spermatic concentrations (200× 10(6) and 400×10(6) spermatozoa/inseminated dose) and number of inseminations (two, three and four or more) on the fertility of 62 mares (military type). Mares were teased and inseminated on Mondays, Wednesdays and Fridays with diluted semen from only one stallion of proven fertility. The conception rates during the first cycle for the two spermatic concentrations were, respectively, 66.7%(20/30) and 65.5%(19/29) and after four cycles they were, respectively, equals to 52.0%(26/50) and 57.8%(26/45) with no difference on conception rate according to the spermatic concentrations (P>0.05). The conception rates for the first cycle after two, three and four or more inseminations were, respectively, 72.0%(18/25), 65.2%(15/23) and 54.6%(6/11) and after four cycles they were, respectively, equals to 59.0%(23/39), 52.5%(21/40) and 50.0%(8/16) with no differences on conception rates according to the number of inseminations. The results suggested that mares could be inseminated using a spermatic concentration of 200×10(6)/inseminated dose on Mondays, Wednesdays and Fridays without any loss of fertility independently of the number of inseminations/cycle

Does certificate of need affect cardiac outcomes and costs?

Several U.S. states enforce Certificate of Need (CON) regulations, which limit the number of hospitals performing open heart surgery or coronary angioplasty. CON regulations were intended to restrain cost growth and improve quality of care. This study compares mortality rates and costs for cardiac care in states with and without CON. CON appears to raise hospital procedure volume and lower the average cost of care. However, CON is associated with little reduction in inpatient mortality, and it may lead hospitals to operate on more patients than they would otherwise. The claimed welfare benefits of CON regulations require careful reconsideration. Copyright Springer Science+Business Media, LLC 2006Regulation, Certificate of need, Outcomes assessment, Cardiac surgery, Costs, I110 Analysis of Health Care Markets, I180 Health: Government Policy, Regulation, Public Health,