Motor-unit Coherence During Isometric Contractions Is Greater in a Hand Muscle of Older Adults

The purpose of this study was to quantify the strength of motor-unit coherence from the first dorsal interosseus muscle in young and old adults using data obtained in a previous study, where no differences in motor-unit synchronization between the two groups were observed.

Motor-unit coherence and its relation with synchrony are influenced by training

The purpose of the study was to quantify the strength of motor-unit coherence from the left and right first dorsal interosseous muscles in untrained, skill-trained (musicians), and strength-trained (weightlifters) individuals who had long-term specialized use of their hand muscles. The strength of motor-unit coherence was quantified from a total of 394 motor-unit pairs in 13 subjects using data from a previous study in which differences were found in the strength of motor-unit synchronization depending on training status. In the present study, we found that the strength of motor-unit coherence was significantly greater in the left compared with the right hand of untrained right-handed subjects with the largest differences observed between 21 and 24 Hz. The strength of motor-unit coherence was lower in both hands of skill-trained subjects (21–27 Hz) and the right (skilled) hand of untrained subjects (21–24 Hz), whereas the largest motor-unit coherence was observed in both hands of strength-trained subjects (3–9 and 21–27 Hz). A strong curvilinear association was observed between motor-unit synchronization and the integral of coherence at 10–30 Hz in all motor-unit pairs (r² = 0.77), and was most pronounced in strength-trained subjects (r² = 0.90). Furthermore, this association was accentuated when using synchronization data with broad peaks (>11 ms), suggesting that the 10- to 30-Hz coherence is due to oscillatory activity in indirect branched common inputs. The altered coherence with training may be due to an interaction between cortical inhibition and the number of direct common inputs to motor neurons in skill- or strength-trained hands.

Life-cycle energy analysis of building integrated photovoltaic systems (BiPVs) with heat recovery unit

Building integrated photovoltaic (BiPV) systems generate electricity, but also heat, which is typically wasted and also reduces the efficiency of generation. A heat recovery unit can be combined with a BiPV system to take advantage of this waste heat, thus providing cogeneration. Two different photovoltaic (PV) cell types were combined with a heat recovery unit and analysed in terms of their life-cycle energy consumption to determine the energy payback period. A net energy analysis of these PV systems has previously been performed, but recent improvements in the data used for this study allow for a more comprehensive assessment of the combined energy used throughout the entire life-cycle of these systems to be performed. Energy payback periods between 4 and 16.5 years were found, depending on the BiPV system. The energy embodied in PV systems is significant, emphasised here due to the innovative use of national average input–output (I–O) data to fill gaps in traditional life-cycle inventories, i.e. hybrid analysis. These findings provide an insight into the net energy savings that are possible with a well-designed and managed BiPV system.

Motor unit synchronization measured by cross-correlation is not influenced by short-term strength training of a hand muscle

The purpose of the study was to quantify the strength of motor unit synchronization and coherence from pairs of concurrently active motor units before and after short-term (4–8 weeks) strength training of the left first dorsal interosseous (FDI) muscle. Five subjects (age 24.8 ± 4.3 years) performed a training protocol three times/week that consisted of six sets of ten maximal isometric index finger abductions, whereas three subjects (age 27.3 ± 6.7 years) acted as controls. Motor unit activity was recorded from pairs of intramuscular electrodes in the FDI muscle with two separate motor unit recording sessions obtained before and after strength training (trained group) or after 4 weeks of normal daily activities that did not involve training (control group). The training intervention resulted in a 54% (45.2 ± 8.3 to 69.5 ± 13.8 N, P = 0.001) increase in maximal index finger abduction force, whereas there was no change in strength in the control group. A total of 163 motor unit pairs (198 single motor units) were examined in both subject groups, with 52 motor unit pairs obtained from 10 recording sessions before training and 51 motor unit pairs from 10 recording sessions after training. Using the cross-correlation procedure, there was no change in the strength of motor unit synchronization following strength training (common input strength index; 0.71 ± 0.41 to 0.67 ± 0.43 pulses/s). Furthermore, motor unit coherence z scores at low (0–10 Hz; 3.9 ± 0.3 before to 4.4 ± 0.4 after) or high (10–30 Hz; 1.7 ± 0.1 before to 1.9 ± 0.1 after) frequencies were not influenced by strength training. These motor unit data indicate that increases in strength following several weeks of training a hand muscle are not accompanied by changes in motor unit synchronization or coherence, suggesting that these features of correlated motor unit activity are not important in the expression of muscle strength.

Attaching unit costs to Australia`s national survey of mental health and wellbeing

Background: In mental health, policy-makers and planners are increasingly being asked to set priorities. This means that health economists, health services researchers and clinical investigators are being called upon to work together to define and measure costs. Typically, these researchers take available service utilisation data and convert them to costs, using a range of assumptions. There are inefficiencies, as individual groups of researchers frequently repeat essentially similar exercises in achieving this end. There are clearly areas where shared or common investment in the development of statistical software syntax, analytical frameworks and other resources could maximise the use of data.

Aims of the Study: This paper reports on an Australian project in which we calculated unit costs for mental health admissions and community encounters. In reporting on these calculations, our purpose is to make the data and the resources associated with them publicly available to researchers interested in conducting economic analyses, and allow them to copy, distribute and modify them, providing that all copies and modifications are available under the same terms and conditions (i.e., in accordance with the `Copyleft' principle). Within this context, the objectives of the paper are to: (i) introduce the `Copyleft' principle; (ii) provide an overview of the methodology we employed to derive the unit costs; (iii) present the unit costs themselves; and (iv) examine the total and mean costs for a range of single and comorbid conditions, as an example of the kind of question that the unit cost data can be used to address.

Method: We took relevant data from the Australian National Survey of Mental Health and Wellbeing (NSMHWB), and developed a set of unit costs for inpatient and community encounters. We then examined total and mean costs for a range of single and comorbid conditions.

Results: We present the unit costs for mental health admissions and mental health community contacts. Our example, which explored the association between comorbidity and total and mean costs, suggested that comorbidly occurring conditions cost more than conditions which occur on their own.

Discussion: Our unit costs, and the materials associated with them, have been published in a freely available form governed by a provision termed `Copyleft'. They provide a valuable resource for researchers wanting to explore economic questions in mental health.

Implications for Health Policies: Our unit costs provide an important resource to inform economic debate in mental health in Australia, particularly in the area of priority-setting. In the past, such debate has largely been based on opinion. Our unit costs provide the underpinning to strengthen the evidence-base of this debate.

Implications for Further Research: We would encourage other Australian researchers to make use of our unit costs in order to foster comparability across studies. We would also encourage Australian and international researchers to adopt the `Copyleft' principle in equivalent circumstances. Furthermore, we suggest that the provision of `Copyleft'-contingent funding to support the development of enabling resources for researchers should be considered in the planning of future large-scale collaborative survey work, both in Australia and overseas.

The relationship between business unit strategy and the use of market research

A study of 42 Australian marketing managers was conducted linking strategy to the use of market research, with a measure known as USER. It was expected that the Miles and Snow strategic typology with its greater emphasis on internal organisational culture, practices and structure would be more powerful than the Porter strategic dimensions in determining the motivation and actual use of market research. The findings showed that neither strategic typology was superior in predicting market research practice. In the study, the USER characteristics most linked to strategy were “the misuse of market research for political purposes” and “internal improvements based on market research.” Two other USER factors “rational use of market research findings” and “use of market research to confirm decisionmaking” were not found to be related to marketing strategy.

Review of first-year engineering and technology units based on student unit evaluations

There is recognition that the first-year of university study is a critical phase in the preparation, motivation and retention of science, mathematics,  engineering and technology (SMET) students. First-year provides the foundation/generic skills upon which students will base their undergraduate studies and professional practice; first-year is where many poorly prepared/at risk students will drop out and contribute to the poor student retention rate observed in the SMET disciplines; and first-year is when students may lose the motivation to pursue their chosen career direction if they find the studies at the commencement of their undergraduate program appear to bear no relationship to their intended career. In 2003, the Learning Resources Advisory Group of the Deakin University School of Engineering and Technology was requested to undertake a review of first-year units in the School’s programs. The information contained in anonymous unit evaluation questionnaires from the years 2000-2002 was used as the basis for analysing student perceptions of first-year units. In unit evaluations, students reported a wide range of issues that impacted negatively on their perception of the content and conduct of first-year units. It was noted that units service taught by other Schools form a significant element of the first-year of all of the Engineering and Technology undergraduate programs – typically 25 to 50 percent of the content. The significant influence of these units on the perceptions of the first-year of the School’s commencing students means that the School should exercise some control over the content and delivery of these units.

Teaching quality and tutorial delivery : experience of a second year marketing unit

The higher education sector, the world over, is faced with the challenging task of servicing an increasingly diverse international student community in the globally competitive education market. The rising expectation of students of education outcomes, varied learning styles and orientations of the student population have brought in challenges such as providing a high quality educational environment with changes in curricula and pedagogy (Coldrake, 2001) to negotiate the cultural and linguistic diversity and the resulting expectations of students. The 'quality' of teaching and learning is high on the agenda among the key issues that had emerged from policy developments to meet these challenges.

Using the SPQ2F instrument (Biggs, 2003) and depth interviews, this paper investigates the study 3J'PToaches of students enrolled in a second year marketing unit in an Australian university focusing on the learning contexts in which learning occurs. The findings indicate that there are no significant differences in study approaches of students and that the study approaches differ according the learning context. The paper concludes that student perceptions on learning contexts assist in the development of teaching strategies that lead to quality outcomes, higher student satisfaction and providing universities a competitive edge in marketing its services to prospective students.

Responding to the learner diversity : an inquiry into the delivery of a second year marketing unit

This paper reports on the outcome of an inquiry into the learner diversity and the delivery of a second year marketing subject in an Australian university. Using Biggs’s revised SPQ2F instrument (Biggs, 2003), it analyses the learning approaches of students and the opportunities for developing teaching strategies for better learning outcomes. The results suggest that overall students seem to adopt deep learning than surface learning though they differ in terms of the learning contexts. Moreover, no significant differences among students in regard to the study approach domains except for minor variation related to specific items in the instrument.

Prototyping a wholly online IT unit

One of the objectives of prototyping is to assess the reactions of users to a proposed system. Reactions are gathered through feedback which then influences the way a final system is designed. This paper reports on a face-to-face undergraduate unit that was converted to online mode (the prototype) in an attempt to provide feedback about an innovative problem-based learning approach for a new unit. The feedback from students through three online surveys was positive overall. The student feedback and the lessons learned by teaching staff through interaction with the prototype suggested how the design and development of the new unit should proceed.

International and culturally inclusive curricula-an engineering management unit audit case study

SEB421 Strategic Issues in Engineering is a final-year engineering management study unit at Deakin University in which the enrolled student population has grown to include significant numbers of international students. Given this change, it was considered timely to conduct a review of the unit, with regard to principles of international and culturally inclusive curricula. Despite the historically white Anglo-Saxon male culture of engineering education in Australia, there are a wide range of international and cultural aspects related to engineering education. A review of the literature reveals a diversity of interpretations of 'internationalisation' and 'cultural inclusiveness'. From a pragmatic perspective, it is noted that organisational policy can provide guidance for academic staff seeking to make courses more inclusive. From a review of the literature and relevant university policies, a list of 'international and culturally inclusive curricula' guidelines for engineering management education was developed. Comparing a prior audit of SEB421 with these guidelines revealed progress on international and culturally inclusive curricula, but identified opportunities for improvement. The guidelines were applied to the curriculum/syllabus, content/study materials, conduct and assessment of the unit, to identify further opportunities for improvement. A plan for improvement of the unit and an associated timetable for this work were developed. It was noted that some changes can be made immediately, while others are contingent upon the timetable imposed by university systems. It was further noted that issues of change within a single study unit intersect with wider issues of program curriculum, and, while pilot activities can provide a start, eventually the wider issue of international and culturally inclusive curricula across the entire undergraduate engineering program needs to be considered.

Managing academic support for international students: the appropriateness of a learning support unit in an Australian tertiary institution

The higher education environment in Australia has undergone a radical change since the 1980s with the phenomenal increase in the intake of international students, particularly from what are referred to as Confucian Heritage Cultures (CHC): China, Korea, Japan, Malaysia and Singapore. Students from these countries view the Australian higher education system very favourably. The present increase in the proportion of full-fee paying students at Australian universities is also a result of decreasing government funding to the Australian higher education sector, which has now risen to be one of the most important elements of the Australian economy. These push-pull factors have drawn more Australian tertiary institution providers into the market place, as they seek more international student enrolments for their domestic campuses and also establish campuses overseas. Potential higher education students are becoming more discerning in their choices and are choosing learning environments that offers them both relevant and stimulating educational experiences and good qualifications, along with a range of both IT and academic support services that cater to their individual learning needs. Increasing competition, both within Australia and internationally, calls for a focus on student satisfaction in order to sustain the existence of the providers. This paper addresses the issue of what international students seek in terms of academic support and demonstrates that present levels of cost efficient services by Australian higher education providers, generally characterized by IT and language support services, are inadequate and do not meet the specific needs of the students.

Are real exchange rates nonlinear with a unit root? Evidence on PPP for Italy : a note

In this article, we apply the recently developed threshold autoregression model to examine both linearity and stationarity of Italy's real exchange rate vis--vis her six trading partner (G6) countries. Our main finding is that Italy's real exchange rate is a nonlinear process that is not characterized by a unit root process for five of six trading partner countries. This provides strong support for purchasing power parity.

Mean reversion in stock prices: new evidence from panel unit root tests

Purpose – There are several studies that investigate evidence for mean reversion in stock prices. However, there is no consensus as to whether stock prices are mean reverting or random walk (unit root) processes. The goal of this paper is to re-examine mean reversion in stock prices.
Design/methodology/approach – The authors use five different panel unit root tests, namely the Im, Pesaran and Shin t-bar test statistic, the Levin and Lin test, the Im, Lee, and Tieslau Lagrangian multiplier test statistic, the seemingly unrelated regression test, and the multivariate augmented Dickey Fuller test advocated by Taylor and Sarno.
Findings – The main finding is that there is no mean reversion of stock prices, consistent with the efficient market hypothesis.
Research limitations/implications – One issue not considered by this study is the role of structural breaks. It may be the case that the efficient market hypothesis is contingent on structural breaks in stock prices. Future studies should model structural breaks.
Practical implications – The findings have implications for econometric modelling, in particular forecasting.
Originality/value – This paper adds to the scarce literature on the mean reverting property of stock prices based on panel data; thus, it should be useful for researchers.