Self-reinforcement, gender-role, and sex of participant in prediction of life satisfaction

There have been conflicting results regarding sex differences and gender role in predicting life satisfaction and no research assessing the relationship between life satisfaction and self-reinforcement. These relationships were evaluated by administering to 182 undergraduates the Bem Sex Role Inventory, the Satisfaction with Life Scale, and the Frequency of Self-reinforcement Questionnaire. A regression analysis showed significant effects for self-reinforcement and gender role in the prediction of life satisfaction. No main effect was found for sex of participant and there were no significant interactions. Scores on measures of self-reinforcement and life satisfaction were moderately correlated.     

Automated docking of glucosyl disaccharides in the glucoamylase active site

To better understand the molecular basis of glucomylase selectivity, low-energy conformers of glucosyl disaccharides obtained from relaxed-residue conformational mapping were flexibly docked into the glucoamylase active site using AutoDock 2.2. This procedure ensures that significant conformational space is searched and can produce bound structures comparable to those obtained by protein crystallography. alpha-Linked glucosyl disaccharides except alpha,alpha-trehalose dock easily into the active site while exclusively beta-linked disaccharides do not, explaining why only the former are glucoamylase substrates. The optimized docking modes are similar at the nonreducing end of the different substrates. Individual atomic energies of intermolecular interaction allow the definite identification of key hydroxyl groups for each substrate. This approach confirmed the versatility of the second subsite of the glucoamylase active site in binding different substrates.     

Alkaline phosphatase (EC 3.1.3.1) in serum is inhibited by physiological concentrations of inorganic phosphate

Natural and artificial manipulation of tissue nonspecific alkaline phosphatase activity indicates that pyrophosphate, phosphoethanolamine, and pyridoxal 5'-phosphate are among the natural substrates for this enzyme. Although inorganic phosphate has been recognized as a competitive inhibitor of this enzyme for many years, the influence of phosphate on alkaline phosphatase activity in serum under physiological conditions has not been previously reported. We examined the kinetics of tissue nonspecific alkaline phosphatase from bovine kidney and sera from 49 patients with a wide range of endogenous phosphate concentrations using pyridoxine 5'-phosphate as a substrate at pH 7.4. For the bovine kidney enzyme, the Km was 0.42 +/- 0.04 micromol/L, and the Ki for phosphate was 2.4 +/- 0.2 micromol/L. Analysis of the kinetics using pyridoxine 5'-phosphate in undiluted serum from 10 subjects with phosphorus ranging from 0.5-2.1 mmol/L and alkaline phosphatase activity ranging from 41-165 nmol/min x mL gave estimates for the Km of 56 +/- 11 micromol/L and for the Ki of 540 +/- 82 micromol/L for phosphate. This indicates that under physiological conditions alkaline phosphatase activity toward pyridoxine 5'-phosphate is reduced approximately 50% by the normal phosphate concentration and that it will increase or decrease significantly in response to changes in phosphate concentration within the ranges observed clinically.     

Diagnosis of uterine abnormalities with radionuclide imaging

A pelvic hypervascular blush often creates a diagnostic dilemma during radionuclide abdominal imaging studies in females. This blush is shown to be due to uterine vascularity that is more prominent in the secretory and menstrual phases of the menstrual cycle. Significant uterine vascularity in the earlier phases is inappropriate and may be pathologic. Three such cases are presented in which increased uterine vascularity on radionuclide imaging during the proliferative phase either lead to a diagnosis or supported a clinical finding.     

Goal-directed evaluation of binarization methods

This paper presents a methodology for evaluation of low-level image analysis methods, using binarization (two-level thresholding) as an example. Binarization of scanned gray scale images is the first step in most document image analysis systems. Selection of an appropriate binarization method for an input image domain is a difficult problem. Typically, a human expert evaluates the binarized images according to his/her visual criteria. However, to conduct an objective evaluation, one needs to investigate how well the subsequent image analysis steps will perform on the binarized image. We call this approach goal-directed evaluation, and it can be used to evaluate other low-level image processing methods as well. Our evaluation of binarization methods is in the context of digit recognition, so we define the performance of the character recognition module as the objective measure. Eleven different locally adaptive binarization methods were evaluated, and Niblack's method gave the best performance     

Variable mesh methods for the numerical solution of two-point singular perturbation problems

In this paper, variable mesh difference methods of third order are derived for the solution of the two-point, second-order, singular perturbation problems y″ = f(x, y, y′, ε). These methods are applied to a number of examples and their superiority over the existing methods is shown.     

Design of a hardware arbiter for multi-microprocessor systems

A simple cost-effective hardware arbiter suitable for multi-microprocessor systems is described. The number of processors is not limited and any one can acquire mastership of the common bus on a priority basis. A daisychain configuration is used to minimize the required interconnection between processor modules and priority is allocated on a round-robin basis. In the realization described, the current bus master is given lowest priority so that it cannot ‘hog’ the bus by making repeated requests.Typical queueing performance of the system is described and metastability problems in flipflop-based arbiters are discussed.