Low impact weight-bearing exercise in an upright posture achieves greater lumbopelvic stability than overground walking

The aim of this study was to determine the kinematic differences between movements on a new exercise device (EX) that promotes a stable trunk over a moving, unstable base of support, and overground walking (OW). Sixteen male participants performed EX and OW trials while their movements were tracked using a 3D motion capture system. Trunk and pelvis range of motion (ROM) were similar between EX and OW in the sagittal and frontal planes, and reduced for EX in the transverse plane. The pelvis was tilted anteriorly, on average, by about 16 degrees in EX compared to OW. Hip and knee ROM were reduced in EX compared to OW. The exercise device appears to promote similar or reduced lumbopelvic motion, compared to walking, which could contribute to more tonic activity of the local lumbopelvic musculature

Resilience of a eucalypt forest woody understorey to long-term (34–55 years) repeated burning in subtropical Australia

We investigated the effects of annual burning since 1952, triennial burning since 1973, fire exclusion since 1946 and infrequent wildfire (one fire in 61 years) on woody understorey vegetation in a dry sclerophyll eucalypt forest, south-eastern Queensland, Australia. We determined the influence of these treatments, and other site variables (rainfall, understorey density, topsoil C : N ratio, tree basal area, distance to watercourse and burn coverage) on plant taxa density, richness and composition. The richness of woody understorey taxa 0–1 m in height was not affected by burning treatments, but richness of woody plants 1–7.5 m in height was lower in the annually burnt treatment than in the triennially burnt treatment from 1989 to 2007. Fire frequency and other site variables explained 34% of the variation in taxa composition (three taxon groups and 10 species), of which 33% of the explained variance was explained by fire treatment and 46% was explained by other site variables. Annual burning between 1974 and 1993 was associated with lower understorey densities mainly due to reduced densities of eucalypts 1–7.5 m in height. Triennial burning during the same period was associated with higher densities of eucalypts 0–7.5 m in height relative to the annually burnt and unburnt treatments. Most woody taxa persisted in the frequently burnt treatments through resprouting mechanisms (e.g. lignotuberous regeneration), and fire patchiness associated with low-intensity burning was also found to be important. Persistence of plants <1 m tall demonstrates the resilience of woody taxa to repeated burning in this ecosystem, although they mainly exist in a suppressed growth state under annual burning

Movement amplitude on the Functional Re-adaptive Exercise Device: deep spinal muscle activity and movement control

Purpose: Lumbar multifidus (LM) and transversus abdominis (TrA) show altered motor control, and LM is atrophied, in people with low-back pain (LBP). The Functional Re-adaptive Exercise Device (FRED) involves cyclical lower-limb movement against minimal resistance in an upright posture. It has been shown to recruit LM and TrA automatically, and may have potential as an intervention for non-specific LBP. However, no studies have yet investigated the effects of changes in FRED movement amplitude on the activity of these muscles. This study aimed to assess the effects of different FRED movement amplitudes on LM and TrA muscle thickness and movement variability, in order to inform an evidence-based exercise prescription. Methods: Lumbar multifidus and TrA thickness of eight healthy male volunteers was examined using ultrasound imaging during FRED exercise, normalised to rest at four different movement amplitudes. Movement variability was also measured. Magnitude-based inferences were used to compare each amplitude. Results: Exercise at all amplitudes recruited LM and TrA more than rest, with thickness increases of approximately 5 mm and 1 mm, respectively. Larger amplitudes also caused increased TrA thickness, LM and TrA muscle thickness variability and movement variability. The data suggest that all amplitudes are useful for recruiting LM and TrA. Conclusions: A progressive training protocol should start in the smallest amplitude, increasing the setting once participants can maintain a consistent movement speed, in order to continue to challenge the motor control system

The immediate effects of exercise using the Functional Re-adaptive Exercise Device on lumbopelvic kinematics in people with and without low back pain

Background - Dysfunction of the lumbar multifidus (LM) and transversus abdominis (TrA) muscles is associated with low back pain (LBP). The Functional Re-adaptive Exercise Device (FRED) has shown potential as a non-specific LBP intervention by automatically recruiting LM and TrA. Loss or lordosis and altered lumbopelvic positioning has also been linked to LBP and is often trained within LM and TrA interventions. The effect that FRED exercise has on lumbopelvic positioning and lumbar lordosis is unknown. Objectives - To assess the effect of FRED exercise on lumbopelvic kinematics and alignment to establish whether FRED exercise promotes a favourable lumbopelvic posture for training LM and TrA. Design - Within and between-group comparison study. Method - One hundred and thirty participants, 74 experiencing LBP, had lumbopelvic kinematic data measured during over-ground walking and FRED exercise. Magnitude-based inferences were used to compare walking with FRED exercise within participants and between the asymptomatic and LBP groups, to establish the effects of FRED exercise on lumbopelvic kinematics, compared to walking, in each group. Results - FRED exercise promotes an immediate change in anterior pelvic tilt by 8.7° compared to walking in the no-LBP and LBP groups. Sagittal-plane spinal extension increased during FRED exercise at all spinal levels by 0.9° in the no-LBP group, and by 1.2° in the LBP group. Conclusions - FRED exercise promotes a lumbopelvic position more conducive to LM and TrA training than walking in both asymptomatic people and those with LBP

Hypogravity reduces trunk admittance and lumbar muscle activation in response to external perturbations

Reduced paraspinal muscle size and flattening of spinal curvatures have been documented after spaceflight. Assessment of trunk adaptations to hypogravity can contribute to develop specific countermeasures. In this study, parabolic flights were used to investigate spinal curvature and muscle responses to hypogravity. Data from five trials at 0.25g, 0.50g and 0.75g were recorded from six participants, positioned in a kneeling-seated position. During the first two trials, participants maintained a normal, upright posture. In the last three trials, small-amplitude perturbations were delivered in the anterior direction at the T10 level. Spinal curvature was estimated using motion capture cameras. Trunk displacement and contact force between the actuator and participant were recorded. Muscle activity responses were collected using intramuscular electromyography (iEMG) of the deep and superficial lumbar multifidus, iliocostalis lumborum, longissimus thoracis, quadratus lumborum, transversus abdominis, obliquus internus and obliquus externus muscles. The root mean square iEMG and the average spinal angles were calculated. Trunk admittance and muscle responses to perturbations were calculated as closed-loop frequency response functions. Compared with 0.75g, 0.25g resulted in: lower activation of the longissimus thoracis (P=0.002); lower responses of the superficial multifidus at low frequencies (P=0.043); lower responses of the superficial multifidus (P=0.029) and iliocostalis lumborum (P=0.043); lower trunk admittance (P=0.037) at intermediate frequencies; and stronger responses of the transversus abdominis at higher frequencies (p=0.032). These findings indicate that exposure to hypogravity reduces trunk admittance, partially compensated by weaker stabilizing contributions of the paraspinal muscles and coinciding with an apparent increase of the deep abdominal muscle activity

Trunk muscle activation during movement with a new exercise device for lumbo‐pelvic reconditioning

Gravitational unloading leads to adaptations of the human body, including the spine and its adjacent structures, making it more vulnerable to injury and pain. The Functional Re‐adaptive Exercise Device (FRED) has been developed to activate the deep spinal muscles, lumbar multifidus (LM) and transversus abdominis (TrA), that provide inter‐segmental control and spinal protection. The FRED provides an unstable base of support and combines weight bearing in up‐right posture with side alternating, elliptical leg movements, without any resistance to movement. The present study investigated the activation of LM, TrA, obliquus externus (OE), obliquus internus (OI), abdominis, and erector spinae (ES) during FRED exercise using intramuscular fine‐wire and surface EMG. Nine healthy male volunteers (27 ± 5 years) have been recruited for the study. FRED exercise was compared with treadmill walking. It was confirmed that LM and TrA were continually active during FRED exercise. Compared with walking, FRED exercise resulted in similar mean activation of LM and TrA, less activation of OE, OI, ES, and greater variability of lumbo‐pelvic muscle activation patterns between individual FRED/gait cycles. These data suggest that FRED continuously engages LM and TrA, and therefore, has the potential as a stationary exercise device to train these muscles

Do Bad Boys Finish First? An Investigation of a Lay Theory of Heterosexual Women\u27s Mate Preferences

The notion that heterosexual women are romantically interested in “bad boys” is a pervasive lay theory of close relationships in U.S. culture. The current research investigated women’s perceptions of bad boys and individual differences in their romantic interest in bad boys. Three studies recruited heterosexual female participants from Amazon’s Mechanical Turk website. Study 1 asked participants to rate their associations of a list of trait adjectives with the bad boy and other prototypes (the “hero,” “nice guy,” and “loser”). Paired comparisons indicated that supportiveness and social dominance traits discriminated among prototypes. Study 2 asked participants to rate their romantic interest in profiles derived from these traits and multilevel models revealed that greater trait attachment anxiety predicted more interest in less supportive prototypes (i.e., bad boy and loser), greater trait attachment avoidance predicted less interest in the ideal prototype (i.e., hero), and associations with self-esteem, sociosexual orientation, and menstrual cycle phase differed by type of interest (sexual or relationship). Study 3 asked participants to complete attachment primes and rate the same profiles. Multilevel models indicated that the avoidant prime decreased sexual interest in supportive prototypes (the hero and nice guy) relative to other primes, while the anxious prime increased relationship interest in socially dominant prototypes (the hero and bad boy) relative to the avoidant prime; however, these results were qualified by trait attachment. The research provides evidence that women’s individual differences relate to less-than-ideal mate choice and that alterations in their state of mind can influence their choices as well

A Study of Three Influencer Archetypes for the Control of Opinion Spread in Time-Varying Social Networks

In this work we consider the impact of information spread in time-varying social networks, where agents request to follow other agents with aligned opinions while dropping ties to neighbors whose posts are too dissimilar to their own views. Opinion control and rhetorical influence has a very long history, employing various methods including education, persuasion, propaganda, marketing, and manipulation through mis-, dis-, and mal-information. The automation of opinion controllers, however, has only recently become easily deployable at a wide scale, with the advent of large language models (LLMs) and generative AI that can translate the quantified commands from opinion controllers into actual content with the appropriate nuance. Automated agents in social networks can be deployed for various purposes, such as breaking up echo chambers, bridging valuable new connections between agents, or shaping the opinions of a target population -- and all of these raise important ethical concerns that deserve serious attention and thoughtful discussion and debate. This paper attempts to contribute to this discussion by considering three archetypal influencing styles observed by human drivers in these settings, comparing and contrasting the impact of these different control methods on the opinions of agents in the network. We will demonstrate the efficacy of current generative AI for generating nuanced content consistent with the command signal from automatic opinion controllers like these, and we will report on frameworks for approaching the relevant ethical considerations.Comment: Submission to IEEE 2024 Conference on Decision and Control. 8 pages, 7 figures, 1 tabl

Desirable ICT Graduate Attributes: Theory vs. Practice

The majority of ICT graduates must begin their careers by successfully fulfilling the requirements advertised within online recruitment sites. Although considerable research into employer requirements is commonly undertaken when preparing curricula, studies investigating how well the graduate attributes on which curricula are based match those required by employers have been limited in terms of the techniques used. This study employs an innovative approach of analyzing online ICT employment advertisements in Australia and the United States to determine the key attributes sought by ICT employers, together with the most commonly required skill groupings. A position-based wrapper system was developed to extract the advertisement data, which was then analyzed using a text mining package. The results are benchmarked against those from standard ICT curricula produced by academic and professional bodies. The findings suggest that employers place greatest emphasis upon experience and technological skills; although current curricula meet these requirements, their emphases warrant revision. There also appear to be differences between professional body curricula and the ISCC ’99 curriculum which was produced by industry and academia, with the latter appearing to match employment market demands more closely