Use of linear semen quality score for classification and decision making in evaluation of individual ejaculates of Holstein bulls

Four hundred seven ejaculates from 15 Holstein bulls collected from December 1984 to June 1985 were evaluated postthaw for viability characteristics (percent progressive motility at 0 h and after 3 h at 37 degrees C incubation, percent intact acrosomal membrane after 3 h at 37 degrees C incubation) and abnormal morphological characteristics [percent head (primary), midpiece, and tail (secondary) abnormalities]. Weighting coefficients for combining viability and abnormality characteristics were generated from between-bull and within-bull variance and covariance matrices. Two hundred ninety-eight additional ejaculates collected from July 1985 to February 1986 were added. Linear quality scores for 705 ejaculates (24 bulls) were the sum of the product of each quality characteristic and weighting coefficients. Univariate analysis yielded significant bull effects for viability and abnormality characteristics and linear quality score. Significant correlations existed between all seminal quality characteristics except primary and secondary abnormalities. A t test with preassigned critical value was used to evaluate each ejaculate to determine rejection from the population. Percent of ejaculates rejected was lower when linear quality score was used than when five independent tests were used. Use of linear quality score to critique semen based on each ejaculate's innate quality could compensate for the loss of bull fertility estimates from declining number of technician-based AI programs.     

Characteristics of a fast transient outward current in guinea pig trigeminal motoneurons

A fast transient voltage dependent outward current (TOC) in trigeminal motoneurons (TMNs) was studied in guinea pig brainstem slices by use of sharp electrodes in combination with single electrode voltage clamp techniques. In solutions containing TTX, low Ca2+/Mn2+ and 20 mM TEA this current activated around -55 to -60 mV from holding potentials negative to resting potential, obtained its peak amplitude within 5 ms and decayed as a single exponential with a time constant of 6-8 ms. Half maximal values for inactivation and activation were -72 and -37 mV, respectively. Bath application of 5 mM 4-AP suppressed this current by approximately 90% and eliminated the early depolarizing transient membrane rectification observed in response to a constant depolarizing current pulse, prolonged the action potential duration, and reduced the threshold voltage and delay to onset of the action potential. It is suggested that this current resembles the typical A-current observed in many CNS neurons and, as a result of its voltage and time dependent properties, could contribute to control of motoneuronal discharge and timing of burst onset during rhythmical jaw movements. Therefore, any cellular models of masticatory activity should include the properties of this current.     

Properties of chitosan/soy protein blended films with added plasticizing agent as a function of solvent type at acidic pH

Pure and blend films from chitosan (CH) and soy protein isolate (SPI) were produced in varying compositions (CH/SPI 75/25, 50/50, 25/75 w/w) based on the solvent type (acetic and formic acids). Glycerol was used as a plasticizer. The interactions between the two biopolymers was confirmed by FTIR and TGA, indicating miscibility and compatibility. Increasing the amount of soy protein decreased the tensile strength and absorptive properties, but improved the ability of the film to withstand thermal degradation. Blend films cast using acetic acid gave higher hydrophobicity, better internal blend miscibility, and better tensile properties than blend films cast from formic acid.     

Acceptance of physical disability and attitudes toward personal appearance.

Investigated appearance management (AM) as a social–psychological variable in 322 physically disabled university students. The questionnaire included an AM and social interaction scale and measures of acceptance of disability. A tendency to regard AM as a form of compensation was associated with a tendency to view physical disability as a central or salient aspect of personal identity. Data suggest that AM is regarded by some as a means for ameliorating the social impact of a physical disability, but is expected to serve only a secondary role in impression formation. The relationship between disability acceptance and predisposition toward AM is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A contribution to the understanding of a.c. anodizing of aluminium

Commercial aluminium has been anodized in 10% v/v sulphuric acid using alternating current. At 20 V no significant differences in colour and thickness between specimens anodized at the neutral and live terminals were detected. At higher voltages the oxide on the neutral specimens was always more yellow and thinner than that on the live specimens. The colouration was attributed to the reduction of sulphate to sulphide during the cathodic half-cycle, no other sulphur-containing species being detected by XPS. EPMA has shown that the total sulphur distribution across the film was practically uniform and independent of the operating conditions, except in thin films, where it was greatest at the free surface. With additions of ferric sulphate to the solution the reduction to sulphide was inhibited and the differences between live and neutral specimens were avoided. The total amount of sulphur remained unchanged at approximately 5% weight and no iron was incorporated in the film.     

A case for information theory-based modelling of human multitasking performance

Technological advances have led to increased prevalence of human multitasking. Traditionally, multitasking performance is measured for each individual task, utilising multiple performance metrics. Recently, the human operator informatic model (HOIM) has been developed as a quantitative model of human–machine interaction capable of measuring multitasking performance with a single metric. In this study, we investigated the performance effects of both a different number of tasks and five different task combinations while maintaining a constant level of overall difficulty. Results indicate that, at a constant difficulty level, neither number of tasks nor task combination significantly affects multitasking performance, indicating the reliability of input baud rate as a measure of system complexity. No task interaction effects were found among the different tasks. This study demonstrates the application of information theory for modelling of human multitasking performance and makes a case for the use of the HOIM in future studies of human information processing.     

Method for estimating the relative contribution of phase and power spectra to the total information in natural-scene patches

A wide variety of recent studies have argued that the human visual system provides an efficient means of processing the information in the natural environment. However, the amount of information (entropy) in the signal can be estimated in a number of ways, and it is has been unclear how much of the information is carried by the different sources of redundancy. The primary difficulty is that there has been no rational way to estimate the entropy of such complex scenes. In this paper, we provide a technique that uses a recent approach to estimating the entropy and dimensionality of natural scenes [D. M. Chandler and D. J. Field, J. Opt. Soc. Am. A 24, 922-941 (2007)] to estimate the amount of information attributable to the power and phase spectra in natural-scene patches. By comparing the entropies of patches that have swapped phase spectra and fixed phase spectra, we demonstrate how to estimate both the amount of information in each type of spectrum and the amount of information that is shared by these spectra (mutual information). We applied this technique to small patches (4×4 and 8×8). From our estimates, we show that the power spectrum of 8×8 patches carries approximately 54% of the total information, the phase spectrum carries 56%, and 10% is mutual information (54%+56%-10%=100%). This technique is currently limited to relatively small image patches, due to the number of patches currently in our collection (on the order of 10?). However, the technique can, in theory, be extended to larger images. Even with these relatively small patches, we discuss how these results can provide important insights into both compression techniques and efficient coding techniques that work with relatively small image patches (e.g., JPEG, sparse coding, independent components analysis).     

Effect of structural period and ground motion parameters on the earthquake response of asymmetric buildings

The results of a parametric study of torsional coupling effects in the response of asymmetric buildings to a grouped selection of 45 strong motion earthquakes from Europe, North America, the Middle East and Southern Pacific are presented. The period dependency of the key response parameters is studied in relation to the site dependent criteria employed by certain earthquake-resistant design codes for specifying the lateral shear forces to be resisted by the structural frames and/or walls. Unlike lateral forces, the torsional response is relatively insensitive to the ration of peak ground accelaration to velocity, which has been used in previous studies as a measure of the effect on earthquake ground motions of site soil conditions and epicentral distance. The results show that the effect of torsional coupling on edge displacement response is more pronounced in stiff, short period structures. However, the dynamic shear and torque responses are relatively insensitive to variations in structural period. Codified design provisions for torsional effects specified in the United States, Canadian and European seismic building regulations are assessed, along with alternative proposals, in relation to the analytical results. It is concluded that in some cases special provisions are needed for short period asymmetric systems, a feature which has been neglected by the codes and inadequately accounted for in previous proposals.