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Developmental influences on the acquisition of tactical decision-making expertise

- Berry, Jason, Abernethy, Bruce

  • Authors: Berry, Jason , Abernethy, Bruce
  • Date: 2009
  • Type: Text , Journal article
  • Relation: International Journal of Sport Psychology Vol. 40, no. 4, Supplement 1 (2009), p. 525-545
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  • Description: The principal purpose of this study was to identify those developmental factors most predictive of adult perceptual and decision-making skill. Qualitative data on developmental experiences and social support were collected from semi-structured interviews of 29 elite Australian Football League (AFL) players, 16 of whom were independently classified by a panel of coaches as expert decision-makers and 13 as less-skilled decision-makers. While high levels of parental support and a fierce desire to win, established from an early age, were evident for all players in the elite sample, the expert decision-makers were more likely to have bad (i) extensive experience of invasion games during their development, (ii) early experience of playing against adults or older children, (iii) playing experience in related sports (especially basketball), and (iv) their father as a coach at some stage during their junior years. The developmental characteristics observed for the expert decision-mak! ers extend quantitative findings on the practice hours of The same cohort (Berry et al., 2008) and indicate that observable differences in decision-making skills amongst adult players, even at an elite level, may be directly linked to each players particular developmental and practice experiences.

Doing tourism research using the pragmatism paradigm : An empirical example

- Pansiri, Jaloni

  • Authors: Pansiri, Jaloni
  • Date: 2006
  • Type: Text , Journal article
  • Relation: Tourism and hospitality planning and development Vol. 3, no. 3 (2006), p. 223-240
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  • Description: There is a call for mixed-methods research in tourism. Many scholars have called for mixing a quantitative and qualitative research methods as a way of enhancing the understanding of a very complex social world that confronts tourism researchers. This paper takes a practical step by showing how mixing of methods can be done. The paper uses data that were collected in Australia. In doing so, the paper shows how data were collected and analysed. Theoretical understanding of the two approaches shows how the findings were arrived at and further supports the argument behind each approach taken in both data collection and analysis. The paper concludes by shedding light on some of the challenges facing mixed-methods researchers, and further provides practical ways of conducting mixed-methods research in tourism effectively.
  • Description: C1
  • Description: 2003001764

The nature of the regional SME

- Lowe, Julian, Henson, Sam

  • Authors: Lowe, Julian , Henson, Sam
  • Date: 2006
  • Type: Text , Journal article
  • Relation: Small enterprise research: The journal of SEAANZ Vol. 14, no. 1 (2006), p. 64-81
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  • Description: In this paper, theories of strategic competitiveness are used as the building blocks for alternative models of the regional firm. These models are used to develop a typology of firms that attempts to explain the fit between a small firm and its regional location. The standard theories based on "industry organization", "resources", and "dynamic capabilities" explain much of the variation observed in the case studies , however a more complete coverage of the regional effects on the nature of firm organization and strategy are provided by introducing "evolutionary" and "infrastructure" based paradigms. The typology is illustrated and discussed, using findings from a qualitative, case-based study of small, Western Victorian firms. Economic and social activity in many regional areas of Australia and the world is in decline, and regional enterprises are an important target of many policy initiative designed to rejuvenate and sustain regions. But what is the nature of regional firms, and what drives their successful development and competitiveness?
  • Description: C1
  • Description: 2003001724

Action research and network development : Creating actionable knowledge

- Braun, Patrice

  • Authors: Braun, Patrice
  • Date: 2006
  • Type: Text , Conference paper
  • Relation: Paper presented at 7th ALARPM and 11th PAR World Congress, Groningen, Netherlands : 21st August, 2006
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  • Description: To make a valuable contribution to our society today, knowledge must be relevant, applicable and actionable. On the side of managers it calls for collaborative approaches to knowledge creation and knowledge transfer between their organisations and knowledge institutions. On the side of academics, it calls for engaged scholarship aimed at knowledge transfer and knowledge contribution to the practical know-how of managers and organisations. Action researchers have long advocated collaborative knowledge creation processes as the way forward, despite the fact that working within an environment that aspires for knowledge to be become applicable and actionable can be complex and challenging. This paper discusses actionable research methods with a focus on networks and learning in a regional development context.
  • Description: E1
  • Description: 2003001943

The lifestyle of our kids (LOOK) project : Outline of methods

- Telford, Richard, Bass, Shona, Budge, Marc, Byrne, Donald, Carlson, John, Coles, David, Cunningham, Ross, Daly, Robin, Dunstan, David, English, Rowena, Fitzgerald, Robert, Eser, Prisca, Gravenmaker, Karen, Haynes, Wayne, Hickman, Peter, Javaid, Ahmad, Jiang, Xiaoli, Lafferty, Tony, McGrath, Mark, Martin, Mary Kay, Naughton, Geraldine, Potter, Julia, Potter, Stacey, Prosser, Laurie, Pyne, David, Reynolds, Graham, Saunders, Philo, Seibel, Markus, Shaw, Jonathan, Southcott, Emma, Srikusalanukul, Wichat, Stuckey, Darryl, Telford, Rohan, Thomas, Kerry, Tallis, Ken, Waring, Paul

Perceptions of the effectiveness of training and development of 'grey-collar' workers in the People's Republic of China

- Hutchings, Katherine, Zhu, Jiuhua, Cooper, Brian, Zhang, Yiming, Shao, Sijun

  • Authors: Hutchings, Katherine , Zhu, Jiuhua , Cooper, Brian , Zhang, Yiming , Shao, Sijun
  • Date: 2009
  • Type: Text , Journal article
  • Relation: Human Resource Development International Vol. 12, no. 3 (2009), p. 279-296
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  • Description: An important human resource development (HRD) implication of the People's Republic of China's (PRC) rapidly expanding economy has been the emergence of a critical shortage of grey-collar workers (GCW). Although ‘grey-collar’ has been commonly used in the West to describe an aging population within the workforce, in China it refers to people who are neither white nor blue collar workers but technicians. The shortage of GCW constrains the PRC's economic and developmental sustainability, and has been recognized in central and provincial government initiatives to increase training and development of employees within these fields. While acknowledged as a policy and organizational problem, there has been no research investigating what organizations are doing to develop these employees. Drawing upon a survey of 310 semi-skilled and skilled employees in Beijing, our findings suggest that while the surveyed organizations are investing heavily in both on- and off-the-job training, employees' perceived value of such differs markedly according to age and position. The research has important implications for China's HRD strategy in suggesting links between training and other human resource management (HRM) functions are yet to be evidenced.

The nature of the regional firm

- Lowe, Julian, Henson, Sam

  • Authors: Lowe, Julian , Henson, Sam
  • Date: 2006
  • Type: Text , Journal article
  • Relation: Small Enterprise Research Vol. 14, no. 1 (2006), p.
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  • Reviewed:
  • Description: In this paper, theories of strategic competitiveness are used as the building blocks for alternative models of the regional firm. These models are used to develop a typology of firms that attempts to explain the fit between a small firm and its regional location. The standard theories based on "industry organization", "resources", and "dynamic capabilities" explain much of the variation observed in the case studies , however a more complete coverage of the regional effects on the nature of firm organization and strategy are provided by introducing "evolutionary" and "infrastructure" based paradigms. The typology is illustrated and discussed, using findings from a qualitative, case-based study of small, Western Victorian firms. Economic and social activity in many regional areas of Australia and the world is in decline, and regional enterprises are an important target of many policy initiative designed to rejuvenate and sustain regions. But what is the nature of regional firms, and what drives their successful development and competitiveness?
  • Description: C1
  • Description: 2003001724

The World Trade Organisation's Doha cotton initiative: a tale of two issues

- Anderson, Kym, Valenzuela, Ernesto

  • Authors: Anderson, Kym , Valenzuela, Ernesto
  • Date: 2008
  • Type: Text , Book chapter
  • Relation: The World Economy: Global Trade Policy 2007 p.
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  • Description: FOR many developing countries, especially in Africa and Central Asia, cotton is an important cash crop. It is receiving attention of late because four poor cotton-exporting West African countries (the Cotton-4: Benin, Burkina Faso, Chad and Mali) have demanded that cotton subsidy and import tariff removal be part of the World Trade Organisation’s Doha Development Agenda (DDA). Cotton subsidies are mostly provided by governments in high-income countries, and part of the US cotton subsidy programme has been ruled illegal following a WTO dispute settlement case brought by Brazil. Hence some reform can be expected soon, especially if the DDA is to live up to its name of being a development round (Sumner, 2006). This paper seeks to provide estimates of what is at stake in terms of cotton

An identification of the meanings(s) of 'development' in a Chinese village context : The first piece of a jigsaw puzzle

- Roy, Cameron

  • Authors: Roy, Cameron
  • Date: 2012
  • Type: Text , Thesis , PhD
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  • Description: This thesis examines the meaning(s) of ‘development’ within a rural village in Sichuan province, China... Importantly, this thesis is a unique snapshot account containing grassroots stories about what development means from the voice and perspective of average Han villagers in a single village in contemporary rural China. (Taken from Abstract)
  • Description: Doctor of Philosophy

The determinants and development of fast bowling performance in cricket

- Feros, Simon

  • Authors: Feros, Simon
  • Date: 2015
  • Type: Text , Thesis , PhD
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  • Description: This thesis sought to reveal the physical and kinematic determinants of pace bowling performance. After drawing on these determinants, a secondary aim was to investigate whether pace bowling performance could be enhanced with chronic resistance training and warm-up strategies. However, before the physical and kinematic determinants of pace bowling performance could be identified, and the effects of two training interventions and warm-ups on pace bowling performance, a new pace bowling test was created, and the test-retest reliability of its performance and kinematic measures were evaluated. Knowledge of a variables’ test-retest reliability is important for interpreting the validity of correlations, but also for the determination of a meaningful change following a training intervention. Only one published study to date has explored the test-retest reliability of a pace bowling assessment, and this test only measured bowling accuracy (1). Previous research has not comprehensively examined the relationships between physical qualities and pace bowling performance. Several important physical qualities (e.g., power, speed-acceleration, flexibility, repeat-sprint ability) have been excluded in correlational research, which may be crucial for optimal pace bowling performance. Furthermore, there is only one published training intervention study on pace bowling research (2). Consequently there is scant evidence for coaches to design training programs proven to enhance pace bowling performance. Baseball pitching studies have trialled the effects of heavy-ball throwing in the warm-up on subsequent throwing velocity and accuracy, but this approach has not been studied in cricket pace bowling, especially after several weeks of training. Therefore, four studies were conducted in this PhD project to address these deficiencies in the literature. The purpose of Study 1 (Chapter 3) was to ascertain the test-retest reliability of bowling performance measures (i.e., bowling speed, bowling accuracy, consistency of bowling speed, and consistency of bowling accuracy) and selected bowling kinematics (i.e., approach speed, step length, step-length phase duration, power phase duration, and knee extension angle at front-foot contact and at ball release) in a novel eight-over test, and for the first four overs of this test. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), and coefficient of variation (CV) were used as measures of test-retest reliability (3). Following a three week familiarisation period of bowling, 13 participants completed a novel eight-over bowling test on two separate days with 4–7 days apart. The most reliable performance measures in the bowling test were peak bowling speed (ICC = 0.948–0.975, CV = 1.3–1.9%) and mean bowling speed (ICC = 0.981–0.987, CV = 1.0–1.3%). Perceived effort was partially reliable (ICC = 0.650– 0.659, CV = 3.8–3.9%). However, mean bowling accuracy (ICC = 0.491–0.685, CV = 12.5–16.8%) and consistency of bowling accuracy failed to meet the pre-set standard for acceptable reliability (ICC = 0.434–0.454, CV = 15.3–19.3%). All bowling kinematic variables except approach speed exhibited acceptable reliability (i.e., ICC > 0.8, CV < 10%). The first four overs of the bowling test exhibited slightly poorer test-retest reliability for all measures, compared to the entire eight-over test. There were no systematic biases (i.e., p > 0.05) detected with all variables between bowling tests, indicating there was no learning or fatigue effects. The smallest worthwhile change was established for all bowling performance and kinematic variables, by multiplying the SEM by 1.5 (4). It is recommended that the eight-over pace bowling test be used as a more comprehensive measure of consistency of bowling speed and consistency of bowling accuracy, as bowlers are more likely to be fatigued. However, if coaches seek to assess pace bowlers in shorter time, delimiting the test to the first four overs is recommended. Both versions of the pace bowling test are only capable of reliably measuring bowling performance outcomes such as peak and mean bowling speed, and perceived effort. The second study of this PhD project examined the relationships between selected physical qualities, bowling kinematics, and bowling performance measures. Another purpose of this novel study was to determine if delivery instructions (i.e., maximal-effort, match-intensity, slower-ball) influenced the strength of the relationships between physical qualities and bowling performance measures. Given that there were three delivery instructions in the bowling test, an objective of this study was to explore the relationship between bowling speed and bowling accuracy (i.e., speed-accuracy trade-off). Thirty-one participants completed an eight-over bowling test in the first session, and a series of physical tests, spread over two separate sessions. Each session was separated by four to seven days. Mean bowling speed (of all pooled deliveries) was significantly correlated to 1-RM pull-up strength (rs [24] = 0.55, p = 0.01) and 20-m sprint time (rs [30] = -0.37, p = 0.04), but the correlations marginally increased as delivery effort increased (i.e., maximal-effort ball). Greater hamstring flexibility was associated with a better consistency of bowling speed, but only for a match-intensity delivery (rs [29] = -0.49, p = 0.01). Repeat-sprint ability (i.e., percent decrement on 10 × 20-m sprints, on every 20 s) displayed a stronger correlation to consistency of bowling speed (rs [21] = -0.42, p = 0.06) than for mean bowling speed (rs [21] = 0.15, p = 0.53). Bench press strength was moderately related to bowling accuracy for a maximal-effort delivery (rs [26] = -0.42, p = 0.03), with weaker but non-significant (p > 0.05) correlations for match-intensity and slower-ball deliveries. Bowling accuracy was also significantly related to peak concentric countermovement jump power (rs [28] = -0.41, p = 0.03) and mean peak concentric countermovement jump power (rs [27] = -0.45, p = 0.02), with both physical qualities displaying stronger correlations as delivery effort increased. Greater reactive strength was negatively associated with mean bowling accuracy (rs [30] = 0.38, p = 0.04) and consistency of bowling accuracy (rs [30] = 0.43, p = 0.02) for maximal-effort deliveries only. Faster bowling speeds were correlated to a longer step length (rs [31] = 0.51, p < 0.01) and quicker power phase duration (rs [31] = -0.45, p = 0.01). A better consistency of bowling accuracy was associated with a faster approach speed (rs [31] = -0.36, p = 0.05) and greater knee flexion angle at ball release (rs [27] = -0.42, p = 0.03). No speedaccuracy trade-off was observed for the group (rs [31] = -0.28, p = 0.12), indicating that most bowlers could be instructed to train at maximal-effort without compromising bowling accuracy. Pull-up strength training and speed-acceleration training were chosen for the “evidence-based” training program (Study 3). Heavy-ball bowling was also considered as part of the evidence-based training program, as it is a specific form of training used previously, and because there was a shortage of significant relationships (p < 0.05) between physical qualities and bowling performance measures in Study 2. The third investigation of this PhD project compared the effects of an eight-week evidence-based training program or normal training program (not a control group) on pace bowling performance, approach speed, speed-acceleration, and pull-up strength. Participants were matched for bowling speed and then randomly split into two training groups, with six participants in each group. After an initial two-week familiarisation period of bowling training, sprint training, and pull-up training, participants completed two training sessions per week, and were tested before and after the training intervention. Testing comprised the four-over pace bowling test (Study 1), 20-m sprint test (Study 2), and 1-RM pull-up test (Study 2). In training, the volume of bowling and sprinting was constant between both groups; the only differences were that the evidence-based training group bowled with heavy balls (250 g and 300 g) as well as a regular ball (156 g), sprinted with a weighted-vest (15% and 20% body mass) and without a weighted-vest, and performed pull-up training. Participants were instructed to deliver each ball with maximal effort in training, as no speed-accuracy trade-off was observed for the sample in Study 2. The evidence-based training group bowled with poorer accuracy and consistency of accuracy, with only a small improvement in peak and mean bowling speed. Heavy-ball bowling may have had a negative transfer to regular-ball bowling. Although speculative, a longer evidence-based program may have significantly enhanced bowling speed. Coaches could use both training programs to develop performance but should be aware that bowling accuracy may suffer with the evidence-based program. The evidence-based training group displayed slower 20-m sprint times following training (0.08 ± 0.05 s). However, the normal training group was also slower (0.10 ± 0.09 s), indicating the potential for speed-acceleration improvement is compromised if speed training is performed immediately after bowling training; most likely due to residual fatigue. Consequently it is recommended that speed-acceleration training be conducted when bowlers are not fatigued, in a separate session, or at the beginning of a session. The evidence-based training group improved their 1-RM pull-up strength by 5.8 ± 6.8 kg (d = 0.68), compared to the normal training group of 0.2 ± 1.7 kg (d = 0.01). The difference between training groups is due to the fact that the normal training group were not prescribed pull-up training. As many participants could not complete the pull-up exercise due to insufficient strength, the dumbbell pullover may be a suitable alternative that is more specific to the motion of the bowling arm (i.e., extended arm). The fourth study of this PhD project explored the acute effects of a heavy-ball bowling warm-up on pace bowling performance, and determined if these acute effects could be enhanced or negated following an evidence-based training program. This study involved the same participants who completed the evidence-based training program in Study 3. These participants were required to perform two different bowling warm-ups (heavy-ball or regular-ball) in pre and post-test period, followed by the four-over pace bowling test (Study 1). In pre-test period, bowling accuracy was 8.8 ± 7.4 cm worse for the heavy-ball warm-up compared to the regular-ball warm-up (d = 1.19). In post-test period however, bowling accuracy was 5.5 ± 6.4 cm better in the heavy-ball warm-up compared to the regular-ball warm-up (d = -0.90). A similar trend was observed for consistency of bowling accuracy. These findings indicate that pace bowlers adapt to heavy-ball bowling, and bowl more accurately with a regular ball if they warm-up with a heavy ball first (but only after eight weeks of heavy-ball training). Coaches could employ a heavy-ball warm-up prior to training or a match, but only after eight weeks of evidence based training. It is hypothesised that a less biomechanically similar exercise to the pace bowling motion such as resisted push-ups / bench press throws could be more effective in eliciting potentiation by activating higher order motor units without negatively transferring to bowling performance. From the studies presented in this thesis, it is concluded that peak and mean bowling speed are the most reliable bowling performance measures, and all kinematic variables apart from approach speed possess excellent reliability. Furthermore, 1-RM pull-up strength and 20-m speed are significantly correlated to bowling speed. An evidence-based training program can develop peak and mean bowling speed, but the cost to bowling accuracy and consistency of bowling accuracy does not make this training program worthwhile in enhancing pace bowling performance. A heavy-ball warm-up impairs bowling accuracy and consistency of bowling accuracy compared to the regular-ball warm-up, but only prior to training with the heavier balls. Pace bowlers adapt to heavyball bowling after eight weeks of training, but must use the heavy balls in the warm-up to bowl more accurately with a regular ball, otherwise pace bowling performance is below optimal.
  • Description: Doctor of Philosophy

Significance of environment in the assesssment of sustainable development: The case for south west Victoria

- Wallis, Anne, Graymore, Michelle, Richards, Anneke J

  • Authors: Wallis, Anne , Graymore, Michelle , Richards, Anneke J
  • Date: 2011
  • Type: Text , Journal article
  • Relation: Ecological Economics Vol. 70, no. 4 (2011), p. 595-605
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  • Description: The assessment of sustainable development is often based on the three pillars of sustainability model using social, economic and environmental indicators. It is thought that by measuring the performance of each system, information can be gained about the sustainability of the whole system. However it seems there has been no attempt to evaluate if such an assumption is true. During the development of a sustainability assessment framework for south west Victoria, Australia, it has become evident that this approach to sustainability assessment does not provide an accurate assessment of system sustainability. The project found that environmental indicators were considered the most important for assessing regional sustainability. As a consequence, the assessment produced shows that in south west Victoria, sustainability is largely determined by the condition of the environment. This finding highlights the current disconnection between the theory and reality of sustainability. Here, we describe a framework for sustainability assessment that attempts to re-connect theory to practice.
  • Description: 2003008701

A multilevel longitudinal study of experiencing virtual presence in adolescence : The role of anxiety and openness to experience in the classroom

- Stavropoulos, Vasileios, Wilson, Peter, Kuss, Daria, Griffiths, Mark, Gentile, Douglas

  • Authors: Stavropoulos, Vasileios , Wilson, Peter , Kuss, Daria , Griffiths, Mark , Gentile, Douglas
  • Date: 2017
  • Type: Text , Journal article
  • Relation: Behaviour & Information Technology Vol. 36, no. 5 (2017), p. 524-539
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  • Description: Presence describes the feeling of reality and immersion that users of virtual/Internet environments have. Importantly, it has been suggested that there are individual and contextual differences regarding susceptibility to presence. These aspects of presence have been linked to both beneficial and disadvantageous uses of the Internet, such as online therapeutic applications and addictive Internet behaviours. In the present study, presence was studied in relation to individual anxiety symptoms and classroom-level openness to experience (OTE) using a normative sample of 648 adolescents aged between 16 and 18 years. Presence was assessed with the Presence II questionnaire, anxiety symptoms with the relevant subscales of the SCL-90-R, and OTE with the Five-Factor Questionnaire. A three-level hierarchical linear model was calculated. Results showed that experiencing presence in virtual environments dropped between the ages of 16 and 18 years. Additionally, although anxiety symptoms were associated with higher presence at 16 years, this association decreased with age. Results also demonstrated that adolescents in classrooms higher on OTE reported reduced level of experiencing presence. The practical and theoretical implications of these findings are discussed.

Telomere dynamics during aging in polygenic left ventricular hypertrophy

- Marques, Francine, Booth, Scott, Prestes, Priscilla, Curl, Claire, Delbridge, Lea, Lewandowski, Paul, Harrap, Stephen, Charchar, Fadi

  • Authors: Marques, Francine , Booth, Scott , Prestes, Priscilla , Curl, Claire , Delbridge, Lea , Lewandowski, Paul , Harrap, Stephen , Charchar, Fadi
  • Date: 2016
  • Type: Text , Journal article
  • Relation: Physiological Genomics Vol. 48, no. 1 (2016), p. 42-49
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  • Description: Short telomeres are associated with increased risk of cardiovascular disease. Here we studied cardiomyocyte telomere length at key ages during the ontogeny of cardiac hypertrophy and failure in the hypertrophic heart rat (HHR) and compared these with the normal heart rat (NHR) control strain. Key ages corresponded with the pathophysiological sequence beginning with fewer cardiomyocytes (2 days), leading to left ventricular hypertrophy (LVH) (13 wk) and subsequently progression to heart failure (38 wk). We measured telomere length, tissue activity of telomerase, mRNA levels of telomerase reverse transcriptase (Tert) and telomerase RNA component (Terc), and expression of the telomeric regulator microRNA miR-34a. Cardiac telomere length was longer in the HHR compared with the control strain at 2 days and 38 wk, but shorter at 13 wk. Neonatal HHR had higher cardiac telomerase activity and expression of Tert and miR-34a. Telomerase activity was not different at 13 or 38 wk. Tert mRNA and Terc RNA were overexpressed at 38 wk, while miR-34a was overexpressed at 13 wk but downregulated at 38 wk. Circulating leukocytes were strongly correlated with cardiac telomere length in the HHR only. The longer neonatal telomeres in HHR are likely to reflect fewer fetal and early postnatal cardiomyocyte cell divisions and explain the reduced total cardiomyocyte complement that predisposes to later hypertrophy and failure. Although shorter telomeres were a feature of cardiac hypertrophy at 13 wk, they were not present at the progression to heart failure at 38 wk. © 2016 the American Physiological Society.

A multilevel longitudinal study of obsessive compulsive symptoms in adolescence: Male gender and emotional stability as protective factors

- Stavropoulos, Vasileios, Moore, Kathleen, Lazaratou, Helen, Dikeos, Dimitris, Gomez, Rapson

  • Authors: Stavropoulos, Vasileios , Moore, Kathleen , Lazaratou, Helen , Dikeos, Dimitris , Gomez, Rapson
  • Date: 2017
  • Type: Text , Journal article
  • Relation: Annals of General Psychiatry Vol. 16, no. 42 (2017), p.1-12
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  • Description: The severity of obsessive compulsive symptoms (OCS) is suggested to be normally distributed in the general population, and they appear to have an impact on a range of aspects of adolescent development. Importantly, there are individual differences regarding susceptibility to OCS. In the present repeated measures study, OCS were studied in relation to gender and emotional stability (as a personality trait) using a normative sample of 515 adolescents at ages 16 and 18 years. OCS were assessed with the relevant subscale of the SCL-90-R and emotional stability with the Five Factor Questionnaire. A three-level hierarchical linear model was calculated to longitudinally assess the over time variations of OCS and their over time links to gender and emotional stability, while controlling for random effects due to the nesting of the data. Experiencing OCS increased with age (between 16 and 18 years). Additionally, male gender and higher emotional stability were associated with lower OCS at 16 years and these remained stable over time. Results indicate age-related and between individual differences on reported OCS that need to be considered for prevention and intervention planning.

Hc-daf-2 encodes an insulin-like receptor kinase in the barber's pole worm, Haemonchus contortus, and restores partial dauer regulation

- Li, Facai, Lok, James, Gasser, Robin, Korhonen, Pasi, Sandeman, Mark, Shi, Deshi, Zhou, Rui, Li, Xiangrui, Zhou, Yanqin, Zhao, Junlong, Hu, Min

  • Authors: Li, Facai , Lok, James , Gasser, Robin , Korhonen, Pasi , Sandeman, Mark , Shi, Deshi , Zhou, Rui , Li, Xiangrui , Zhou, Yanqin , Zhao, Junlong , Hu, Min
  • Date: 2014
  • Type: Text , Journal article
  • Relation: International Journal for Parasitology Vol. 44, no. 7 (2014), p. 485-496
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  • Description: Infective L3s (iL3s) of parasitic nematodes share common behavioural, morphological and developmental characteristics with the developmentally arrested (dauer) larvae of the free-living nematode Caenorhabditis elegans. It is proposed that similar molecular mechanisms regulate entry into or exit from the dauer stage in C. elegans, and the transition from free-living to parasitic forms of parasitic nematodes. In C. elegans, one of the key factors regulating the dauer transition is the insulin-like receptor (designated Ce-DAF-2) encoded by the gene Ce-daf-2. However, nothing is known about DAF-2 homologues in most parasitic nematodes. Here, using a PCR-based approach, we identified and characterised a gene (Hc-daf-2) and its inferred product (Hc-DAF-2) in Haemonchus contortus (a socioeconomically important parasitic nematode of ruminants). The sequence of Hc-DAF-2 displays significant sequence homology to insulin receptors (IR) in both vertebrates and invertebrates, and contains conserved structural domains. A sequence encoding an important proteolytic motif (RKRR) identified in the predicted peptide sequence of Hc-DAF-2 is consistent with that of the human IR, suggesting that it is involved in the formation of the IR complex. The Hc-daf-2 gene was transcribed in all life stages of H. contortus, with a significant up-regulation in the iL3 compared with other stages. To compare patterns of expression between Hc-daf-2 and Ce-daf-2, reporter constructs fusing the Ce-daf-2 or Hc-daf-2 promoter to sequence encoding GFP were microinjected into the N2 strain of C. elegans, and transgenic lines were established and examined. Both genes showed similar patterns of expression in amphidial (head) neurons, which relate to sensation and signal transduction. Further study by heterologous genetic complementation in a daf-2-deficient strain of C. elegans (CB1370) showed partial rescue of function by Hc-daf-2. Taken together, these findings provide a first insight into the roles of Hc-daf-2/. Hc-DAF-2 in the biology and development of H. contortus, particularly in the transition to parasitism. © 2014 Australian Society for Parasitology Inc.

Zinc transporters maintain longevity by influencing insulin/IGF-1 activity in Caenorhabditis elegans

- Novakovic, Stevan, Molesworth, Luke, Gourley, Taylin, Boag, Peter, Davis, Gregory

  • Authors: Novakovic, Stevan , Molesworth, Luke , Gourley, Taylin , Boag, Peter , Davis, Gregory
  • Date: 2020
  • Type: Text , Journal article
  • Relation: FEBS Letters Vol. 594, no. 9 (2020), p. 1424-1432
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  • Description: Adequate dietary intake of essential metals such as zinc is important for maintaining homeostasis. Abnormal zinc intake in Caenorhabditis elegans has been shown to increase or decrease normal lifespan by influencing the insulin/IGF-1 pathway. Distribution of zinc is achieved by a family of highly conserved zinc transport proteins (ZIPT in C. elegans). This study investigated the role of the zipt family of genes and showed that depletion of individual zipt genes results in a decreased lifespan. Moreover, zipt-16 and zipt-17 mutants synthetically interact with the insulin/IGF cofactors daf-16 and skn-1, and cause abnormal localisation of DAF-16. This study suggests that the zipt family of genes are required for maintaining normal lifespan through influencing the insulin/IGF-1 pathway. © 2019 Federation of European Biochemical Societies
  • Description: This study was supported by the resources at Federation University; no external funding was used to fund this study. We acknowledge the Caenorhabditis elegans Genetics Centre for the strains used in this study and Hannah Tatnell (Federation University) for technical assistance.
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