Validity of an operational management assessment program.

Examined the validity of an assessment program by reviewing the career progress of 1,086 employees in sales, service, and administrative functions after they were assessed. Although Ss participating in the program were nominated on the basis of being promotable, raters found that more than 1/4 were unqualified, and the others were widely differentiated. Ratings were used to move Ss into 1st-line management, but the relationship of ratings to 1st promotions was moderate enought to reduce fears of "crown prince" or "kiss of death" effects. Participation did not seem to demotivate these Ss. Assessment ratings substantially correlated with 2 major criteria, 2nd-level promotions and demotions from 1st-line management. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Utility system effects of space plasmas

Space plasmas and their unpredictable effects are objects of intensive study by NASA, the armed services, and participants in the International Geophysical Year investigations. There seems to be a direct correlation between solar hyperactivity and geomagnetic, as well as magnetotelluric, field fluctuations. Cosmic rays increase in intensity; and radio communications suffer. Various agencies are predicting an unusual increase in solar activity by the end of this year. What, if any, will be the observable result?     

Calculation of the Transient Response of Long Chains of Slightly Lossy Coupled Resonators

Methods of calculating and of illustrating the transient response of chains of coupled resonators are discussed. Such calculations are particularly useful in understanding the rf field behavior in linear accelerator structures, both of the drift tube and waveguide or coupled cavity types. Resonator chains are also employed in certain kinds of filters and delay lines; the methods to be discussed are applicable in these areas, as well. A frequency adjustment is presented which permits difference equations with a large time step to accurately represent the differential equations for slightly lossy coupled resonators.     

Implementing sparse matrix techniques in the erato code

In the variational form of the ideal magnetohydrodynamic equations for a toroidal geometry two of the three displacement components appear to be “one-dimensional”. By an adequate discretization procedure the matrix blocks of the block-diagonal matrix do not entirely overlap. This feature can be used to advantage when solving the eigenvalue problem by sparse matrix techniques. Appreciable gains in computing time, memory and disk storage as well as in input-output operations can be obtained.     

Intravital leukocyte detection using the gradient inverse coefficient of variation

The problem of identifying and counting rolling leukocytes within intravital microscopy is of both theoretical and practical interest. Currently, methods exist for tracking rolling leukocytes in vivo, but these methods rely on manual detection of the cells. In this paper we propose a technique for accurately detecting rolling leukocytes based on Bayesian classification. The classification depends on a feature score, the gradient inverse coefficient of variation (GICOV), which serves to discriminate rolling leukocytes from a cluttered environment. The leukocyte detection process consists of three sequential steps: the first step utilizes an ellipse matching algorithm to coarsely identify the leukocytes by finding the ellipses with a locally maximal GICOV. In the second step, starting from each of the ellipses found in the first step, a B-spline snake is evolved to refine the leukocytes boundaries by maximizing the associated GICOV score. The third and final step retains only the extracted contours that have a GICOV score above the analytically determined threshold. Experimental results using 327 rolling leukocytes were compared to those of human experts and currently used methods. The proposed GICOV method achieves 78.6% leukocyte detection accuracy with 13.1% false alarm rate.     

Resolution-effective diameters for asymmetric-knife-edge pinhole collimators

The effects of penetration are included in the formulas for the prediction of the resolution of pinhole collimators through the use of effective diameters. Expressions of the resolution-effective diameter for pinholes with a double-knife-edge (DKE) profile are available in the literature. In this paper the expressions applicable to asymmetric-knife-edge (AKE) profiles, which include the important case of the single-knife-edge (SKE), are presented. Results indicate that the simplest methods that are still accurate in the calculation of DKE effective diameters do not produce in general formulas with similar accuracy for AKE profiles, due to increased susceptibility to penetration. Especially at high energy (365 keV), for the SKE case more advanced formulas are necessary and were, therefore, derived.     

Mass spectrometric differentiation of linear peptides composed of L-amino acids from isomers containing one D-amino acid residue

MS/MS of electrosprayed ions is shown to have the capacity to discriminate between peptides that differ by configuration about their alpha-carbons. It is not necessary for the peptides to possess tertiary structures that are affected by stereochemistry, since five epimers of the pentapeptide, H2N-Gly-Leu-Ser-Phe-Ala-OH (GLSFA) all display different collisionally activated dissociation (CAD) patterns of their protonated parent ions. The figure of merit, r, is a ratio of ratios of fragment ion abundances between stereoisomers, where r = 1 corresponds to no stereochemical effect. Values of r as high as 3.8 are seen for diastereomer pairs. Stereochemical effects are also seen for the diprotonated dodecapeptide H2N-Leu-Val-Phe-Phe-Ala-Glu-Asp-Val-Gly-Ser-Asn-Lys-OH (LVFFAEDVGSNK), a tryptic fragment from the amyloid beta-protein. Triply charged complexes of the protonated dodecapeptide with cobalt(II) ions undergo CAD at lower collision energies than do doubly protonated LVFFAEDVGSNK ions. Statistically significant (p < 0.01) differences between the all-L-dodecapeptide and the ones containing a d-serine or a D-aspartic acid are observed.     

Dissolution behaviour of plasma sprayed apatite coatings

Understanding the interaction of bioactive coatings with aqueous media is essential for development of systems possessing rapid osteointegration and durability. An in vitro study of a commercial, plasma sprayed hydroxyapatite coating has been undertaken. The coating behaviour when test coupons were immersed in water, simulated body fluid and foetal calf serum has been examined. The principal aim was to characterise, in detail, any structural changes to the coatings and, in particular, examine features of any new layers formed. The amorphous phase of the coating showed preferential dissolution in all media. The rate of dissolution was greatest in water and the process was initially retarded in the foetal calf serum. A nanocrystallite apatite layer was shown to precipitate on the coatings in all media although this was significantly enhanced in simulated body fluid. The features of this layer (e.g., lattice parameters, crystallite size etc.) were quantified by adopting a novel approach to the X-ray diffraction data analysis. The results are discussed in the context of similar studies and implications for in vivo behaviour.