GHP: a maple package for performing calculations in the Geroch-Held-Penrose formalism

We present a new symbolic algebra package, written for Maple, for performing computations in the Geroch-Held-Penrose formalism. We demonstrate the essential features and capabilities of our package by investigating Petrov-D vacuum solutions of Einstein's field equations.

Psychometric evaluation of the body change inventory: an assessment instrument for adolescent boys and girls

A new instrument, the Body Change Inventory, was developed to provide an assessment of body change strategies that are used by both adolescent girls and boys. The novel aspect of this instrument is that it evaluates strategies to increase body size and increase muscle size, as well strategies to decrease body size. Independent samples of adolescent girls and boys aged between 11 and 17 years (N=1732) participated in four studies. The revised instrument consisted of three body change scales—Strategies to Decrease Body Size, Strategies to Increase Body Size, and Strategies to Increase Muscle Size. The studies demonstrated content validity, construct validity, internal consistency, and concurrent and discriminant validity for the new scales. The new scales provide a valuable addition in the literature for assessing three global body change strategies among adolescent girls and boys. They are needed in order to examine further the normative development of different kinds of body change strategies and how these may lead to behavioural problems such as disordered eating, exercise dependence, and steroid use.

Effect of yarn hairiness on energy consumption in rotating a ring-spun yarn package

The effect of yarn hairiness on energy consumption when rotating a ring-spun yarn package is investigated theoretically and experimentally. A theoretical model is developed to calculate the energy required to rotate hair fibers, based on hair length and number as well as package speed and size. A single spindle test rig is used to verify the theoretical prediction. The experimental results confirm the theoretical prediction that the package power increases with increased yarn hairiness level and spindle speed.

Validity and reliability of a physical activity recall instrument among overweight and non-overweight men and women

This study examined the validity and reliability of survey items measuring one-week recall of physical activity (PA) and examined differences by weight status. A sub-aim of the study was to objectively assess the intensity of activity that most closely matches self-report. A questionnaire was administered to adults twice, three days apart. It was again administered after subjects wore a MTI/CSA accelerometer for seven days (n = 118). Several metabolic equivalent (MET) thresholds were applied to the accelerometer data. Agreement between test and re- test estimates of sufficient physical activity for health benefits (150 min/week) was high (% agreement > 90%). Correlations (rho) between total reported PA (mins/day) and accelerometer data were 0.29 (p < 0.05) among men and 0.25 (p < 0.05) among women. Among men, self- reported duration of moderate PA (3-5.9 METS) and accelerometer data were significantly correlated (rho = 0.40, p < 0.01), with no differences by weight status. Among women, a significant relationship was found only for those who were not overweight (rho = 0.52, p < 0.001). A significant correlation between self-reported duration of vigorous PA (6+ METS) and accelerometer data was only found for overweight men (rho = 0.40, p < 0.05). When lower MET thresholds were applied to the accelerometer data, women's reported duration of moderate-intensity PA was most strongly correlated with moderate PA (accelerometer) defined as 2.0-5.9 METS (rho = 0.39, p < 0.01). The recall instrument provides a consistent measure of physical activity and validation coefficients were similar to those obtained for other physical activity recall questionnaires. However, the ability to measure PA by self-report may vary by weight status.

The GHP II package with applications

We present an advanced version of the Maple package GHP called GHPII. In it we provide a number of additional sophisticated tools to assist with problems formulated in the Geroch-Held-Penrose (ghp) formalism. The first part of this article discusses these new tools while in the second part we shall apply the ghp formalism, using the GHPII routines, to vacuum Petrov type D spacetimes and shear-free perfect fluids. We prove that for all shear-free perfect fluids with a barotropic equation of state, where two of the principal null directions are coplanar with the fluid four-velocity and vorticity then either the expansion or vorticity of the fluid must be zero.

Skin friction coefficient on a yarn package surface in ring spinning

The skin friction coefficient on the surface of a rotating yarn package affects the power required to drive the package. This paper examines the relationship between the skin friction coefficient on the package surface and its diameter and rotating speed, based on the fundamentals of aerodynamics and the experimental results of power consumption. Skin friction coefficients on the surfaces of an airplane, car top, and yarn package are discussed. The results indicate that the skin friction coefficient on the package surface without hairiness depends on the package diameter and spindle speed only. The skin friction coefficient on the yarn package surface is about three times that on the top surface of a car, and is about twenty times that on an airplane surface. The power consumed to overcome skin friction drag is more than that consumed to drive the spindle if the spindle speed is very slow. However, the situation reverses when the spindle speed is fast.

Development, implementation, and evaluation of a continence education package in acute and subacute care settings

OBJECTIVE: The objective of the study was to trial and evaluate the effect that a discharge Continence Education Package (CEP) had on patients' continence awareness and management preferences.
DESIGN: An exploratory descriptive design was used.
SETTINGS AND SUBJECTS: A total of 631 participants were included in the study: 352 females (55.8%) and 279 males (44.2%) from 4 rural and regional settings in Victoria, Australia.
INSTRUMENTS AND METHODS: A specifically designed questionnaire was used to assess participants' knowledge of incontinence and its management and also to investigate their treatment preferences and intentions if they experienced this type of problem. Data were collected at 2 time periods. Specifically, patients were interviewed before discharge from acute and subacute settings identified as Time 1 (T1). Then the participants were given the CEP and asked to complete a similar questionnaire.
RESULTS: The findings revealed that fewer than 25% of participants had received information on continence before the study being conducted, yet the majority had indicated that they had experienced continence symptoms. The majority of participants found the CEP easy to understand (98.2%) and helpful (95.3%). Most participants said it provided them with information about types of actions to take and/or treatment options for incontinence problems. It also raised their awareness of the signs and symptoms associated with incontinence and provided them with a useful self-administered gauge with which to assess their continence status.
CONCLUSIONS: These findings suggest that the CEP may be a useful educational tool for use in the general population.

Effect of a self-directed learning package on emergency nurses` knowledge of assessment of oxygenation and use of supplemental oxygen

Abstract Emergency nurses frequently and independently make decisions regarding supplemental oxygen. The importance of these decisions for patients is highlighted by the well documented association between respiratory dysfunction and adverse events. This study aimed to: (i) examine the effect of educational preparation on emergency nurses' knowledge of assessment of oxygenation, and the use of supplemental oxygen; (ii) explore the impact of existing knowledge on decisions related to the implementation of supplemental oxygen; and (iii) explore nurses' characteristics that were associated with effectiveness of the educational preparation. A pretest/post-test, controlled, quasi-experimental design was used in this study. Educational preparation was effective in increasing emergency nurses' knowledge. Baseline level of knowledge was predictive of reports of independent decisions regarding the implementation of oxygen. There was a significant positive relationship between postgraduate qualification in emergency nursing and the effect of education, and significant negative relationships between effect of education and baseline level of knowledge and daily decisions to implement supplemental oxygen.

Development, reliability and validity of an instrument measuring the attitudes and knowledge of emergency department staff regarding the emergency nurse practitioner role

Introduction: The Emergency Department (ED) at The Northern Hospital is currently participating in the Victorian Department of Human Services funded Emergency Nurse Practitioner Project. This project aims to develop, implement and evaluate the Emergency Nurse Practitioner role in Victorian EDs. This led to a need to develop a specific data collection tool called The Northern Emergency Nurse Practitioner Staff Survey to examine the knowledge and attitudes of ED medical and nursing staff. This paper describes the development of The Northern Emergency Nurse Practitioner Staff Survey and presents the results of reliability and validity studies. Method: Twenty-five items were developed and piloted on a sample of 58 ED medical and nursing staff. Content and face validity were established by expert panel review. Reliability was established by tests of unidimensionality, exploratory factor analysis and internal consistency. Results: Four items were discarded because of low item to total correlation. Exploratory factor analysis of the remaining items revealed five factors with eigenvalues >1 and acceptable correlation coefficients that explained 76.7% of the variance. Cronbach’s coefficent α for these items was 0.926 indicating a high degree of internal consistency. The factors were titled to reflect the content domain of the items in each factor and the factors arranged in a logical sequence to form the final version of The Northern Emergency Nurse Practitioner Survey.

Development of an instrument to evaluate the quality of delivered information systems

Delivered information systems are an integral part of many organisations’ information technology infrastructure. Their dynamic nature creates new challenges, not the least of which is the need to measure the quality/effectiveness of these systems. Given the size of investment in these systems, it would be invaluable for business to formulate a fresh, simple, easy to administer, multi-dimensional instrument capable of measuring the quality of delivered information systems or applications. Such an instrument would provide a practical and efficient means to pinpoint areas that key stakeholders, ranging from end-users to managers, perceive as requiring attention. In this paper, we report on the development of one such instrument. This instrument addresses key areas of performance and uses multiple statements to enhance stakeholders’ understanding of these areas.

The MORTN market orientation instrument - an empirical analysis

This paper focuses on Deshpande and Farley's (1998) MORTN market orientation instrument. Specifically, the paper investigates empirically the factor structure and reliability of the supposedly unidimensional instrument. When the MORTN instrument was tested utilising Australian organisations, a two-dimensional factor structure was found to fit the data more acceptably then the unidimensional structure proposed by Deshpande and Farley. These dimensions may be characterised as being Customer/Market Intelligence (Dimension One) and Customer Service (Dimension Two).

The utility of a workplace injury instrument in prediction of workplace injury

Workplace injuries are common and destructive to persons, organisations, and society. Various instruments presently exist that are designed to assess the factors underlying workplace injury. The study reports on the construct and predictive validity of a 46-item instrument, the safety perception survey (SPS), currently used to assess safety climate in industrial organisations throughout Australia. Initially, factor analysis was conducted on the data from a sample of 1238 employees from nine organisations, which indicated a one-factor solution, was the best fit. A structural equation model (SEM) linking injury rates to the safety climate measure for 16 sub-groups of six industrial organisations indicated that the measure contributed just 23% of the variance in injury rates. Interestingly, the results indicated that the number of employees was a better and more significant predictor of injury (R² = 0.48). It is proposed that the SPS as is would need to be modified significantly from its current form to produce improvements in validity, as in its current form the survey is no more predictive of injury than organisational size. Future research into safety climate measures should incorporate predictive validity analysis on injury rates, as for many organisations; this is a performance outcome measure.

A simplified stroke rehabilitation assessment of movement instrument

Background and Purpose. An efficient, reliable, and valid instrument for assessing motor function in patients with stroke is needed by both clinicians and researchers. To improve administration efficiency, we applied the multidimensional Rasch model to the 30-item, 3-subscale Stroke Rehabilitation Assessment of Movement (STREAM) instrument to produce a concise, reliable, and valid instrument (simplified STREAM [S-STREAM]) for measuring motor function in patients with stroke. Subjects and Methods. The STREAM (consisting of 3 subscales: upper-limb movements, lower-limb movements, and mobility) was administered to 351 subjects with first stroke occurrence and a median time after stroke of 19.5 months. The unidimensionality of each subscale of the STREAM first was verified with unidimensional Rasch analysis. Each subscale of the STREAM then was simplified by deleting redundant items on the basis of expert opinion and the results of the Rasch analysis. The Rasch reliability of the S-STREAM and the concurrent validity of the S-STREAM with the STREAM were examined with multidimensional Rasch analysis and the intraclass correlation coefficient (ICC), respectively. Results. After deleting the items that did not fit the Rasch model, we found that the 8-item upper-limb movement subscale, the 9-item lower-limb movement subscale, and the 10-item mobility subscale assessed single, unidimensional upper-limb movements, lower-limb movements, and mobility, respectively. We selected 5 items from each subscale to construct the S-STREAM and found that the reliability of each subscale of the resulting simplified instrument was high (Rasch reliability coefficients of [greater than or equal to] .91). The agreement between the subscale scores (Rasch estimates) of the S-STREAM and those of the STREAM was excellent (ICC of [greater than or equal to] .99, with a lower limit for the 95% confidence interval of [greater than or equal to] .985), indicating good concurrent validity of the S-STREAM with the STREAM. Discussion and Conclusion. The S-STREAM demonstrates high Rasch reliability, unidimensionality, and concurrent validity with the STREAM in patients with stroke. Furthermore, the S-STREAM is efficient to administer, as it consists of only half the number of items in the original STREAM. Additional studies to examine other psychometric properties (eg, predictive validity and responsiveness) of the S-STREAM or its psychometric properties in various recovery stages after stroke are needed to further establish its utility in both clinical and research settings.