The changing presentation of pyloric stenosis

A triplet pregnancy in a 23-year-old woman was terminated at 15 weeks of gestation because of her severe hypertension, lung edema, and secondary hyperthyroidism. The pregnancy consisted of a hydatidiform mole with a 46,XY karyotype and two fetuses each with 46,XX and a 46,XY karyotype. To determine the zygosity and genetic origin of the mole and fetuses, PCR- and computer-assisted genotyping were performed at 27 CA-repeat marker loci that were distributed evenly over the genome. As a result, genotypes of the three pregnancy products were distinct from each other, indicating that the triplets were trizygotic. The mole lacked any maternal alleles but inherited both of the paternal alleles and/or one paternal allele in duplicate. This, along with the XY sex chromosome constitution, indicated that the mole resulted from dispermic androgenesis. The mother developed a persistent trophoblastic tumor thereafter.     

Individual differences and autonomic control: Absorption, hypnotic susceptibility, and the unilateral control of skin temperature.

Proposed to (a) replicate earlier findings that human Ss could voluntarily control peripheral skin temperature, (b) test the hypothesis that hypnotic susceptibility and the capacity for absorbed, imaginative attention would enhance autonomic learning and performance, and (c) demonstrate a learning effect, if one exists. A comparison was made with 7 Ss who scored high and 7 Ss who scored low on both a modified version of the Harvard Group Scale of Hypnotic Susceptibility and the Tellegen Absorption Scale. Auditory feedback was used to train Ss to produce a difference in skin temperature in one hand relative to the other in a direction specified by the E. Large and reliable performance and learning effects were found, but they were unrelated to hypnotic susceptibility or the capacity for absorbed, imaginative attention. Variables that might account for individual differences in learning and performance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Accounting for uncertainty in control-relevant statistics

To make appropriate decisions based on common indices used in control, both the point estimates and their uncertainties must be known. Many control-relevant statistics, such as model predictions, gain margins and other frequency domain quantities, are functions of parameters of process models. Confidence regions for these quantities are most often calculated under the assumption that these quantities have an asymptotic limiting normal distribution. These confidence regions may be erroneous, and very misleading, as the asymptotic results ignore the influence of parameter nonlinearities. In addition, proximity of the model parameters to stability/invertibility boundaries also distorts the confidence regions from those predicted from asymptotic theory. Generalized profiling is a flexible numerical method for constructing confidence intervals and confidence regions for model parameters, and functions of model parameters. Applications in nonlinear regression [D. Bates, D. Watts, Nonlinear Regression Analysis and Its Applications, John Wiley & Sons, New York, 1988] indicate that it provides a much more accurate representation of uncertainty in those instances when the asymptotic uncertainty results are inaccurate or misleading. Generalized profiling is based on the likelihood approach to quantifying uncertainty. The numerical construction of these likelihood uncertainty regions requires solution to a series of constrained optimization problems. Computationally efficient diagnostic tests, motivated by profiling, are developed. These can be effectively employed as screening tools to indicate when the asymptotic results are most likely to be inadequate.     

Aortic perforation during lumbar laminectomy

A method to determine the optimal replacement time for dye affinity adsorbents used in protein purification processes that are subjected to severe regeneration conditions has been developed. To demonstrate the utility of the method, an experimental fixed-bed decay model was employed to determine the optimum number of cycles for the adsorbent replacement. This number is a function of the column regeneration frequency and of the capital and operation costs. The implications of the results on the design and operation of dye-ligand chromatographic processes are discussed.