The pattern of coupling dynamics between postural motion, isotonic hand movements and physiological tremor

This study was designed to examine differences in the coupling dynamics between upper limb motion, physiological tremor and whole body postural sway in young healthy adults. Acceleration of the hand and fingers, forearm EMG activity and postural sway data were recorded. Estimation of the degree of bilateral and limb motion-postural sway coupling was determined by cross correlation, coherence and Cross-ApEn analyses. The results of the analysis revealed that, under postural tremor conditions, there was no significant coupling between limbs, muscles or sway across all metrics of coupling. In contrast, performing a rapid alternating flexion/extension movement about the wrist joint (with one or both limbs) resulted in stronger coupling between limb motion and postural sway. These results support the view that, for physiological tremor responses, the control of postural sway is maintained independent to tremor in the upper limb. However, increasing the level of movement about a distal segment of one arm (or both) leads to increased coupling throughout the body. The basis for this increased coupling would appear to be related to the enhanced neural drive to task-specific muscles within the upper limb.

No specific role for the manual motor system in processing the meanings of words related to the hand

The present study explored whether semantic and motor systems are functionally interwoven via the use of a dual-task paradigm. According to embodied language accounts that propose an automatic and necessary involvement of the motor system in conceptual processing, concurrent processing of hand-related information should interfere more with hand movements than processing of unrelated body-part (i.e., foot, mouth) information. Across three experiments, 100 right-handed participants performed left- or right-hand tapping movements while repeatedly reading action words related to different body-parts, or different body-part names, in both aloud and silent conditions. Concurrent reading of single words related to specific body-parts, or the same words embedded in sentences differing in syntactic and phonological complexity (to manipulate context-relevant processing), and reading while viewing videos of the actions and body-parts described by the target words (to elicit visuomotor associations) all interfered with right-hand but not left-hand tapping rate. However, this motor interference was not affected differentially by hand-related stimuli. Thus, the results provide no support for proposals that body-part specific resources in cortical motor systems are shared between overt manual movements and meaning-related processing of words related to the hand.

Quantification of functional hand grip using electromyography and inertial sensor-derived accelerations: Clinical implications

Background Assessing hand injury is of great interest given the level of involvement of the hand with the environment. Knowing different assessment systems and their limitations generates new perspectives. The integration of digital systems (accelerometry and electromyography) as a tool to supplement functional assessment allows the clinician to know more about the motor component and its relation to movement. Therefore, the purpose of this study was the kinematic and electromyography analysis during functional hand movements. Method Ten subjects carried out six functional movements (terminal pinch, termino-lateral pinch, tripod pinch, power grip, extension grip and ball grip). Muscle activity (hand and forearm) was measured in real time using electromyograms, acquired with the Mega ME 6000, whilst acceleration was measured using the AcceleGlove. Results Electrical activity and acceleration variables were recorded simultaneously during the carrying out of the functional movements. The acceleration outcome variables were the modular vectors of each finger of the hand and the palm. In the electromyography, the main variables were normalized by the mean and by the maximum muscle activity of the thenar region, hypothenar, first interosseous dorsal, wrist flexors, carpal flexors and wrist extensors. Conclusions Knowing muscle behavior allows the clinician to take a more direct approach in the treatment. Based on the results, the tripod grip shows greater kinetic activity and the middle finger is the most relevant in this regard. Ball grip involves most muscle activity, with the thenar region playing a fundamental role in hand activity. Clinical relevance Relating muscle activation, movements, individual load and displacement offers the possibility to proceed with rehabilitation by individual component.

Did you see that? Dissociating advanced visual information and ball flight constrains perception and action processes during one-handed catching

The integration of separate, yet complimentary, cortical pathways appears to play a role in visual perception and action when intercepting objects. The ventral system is responsible for object recognition and identification, while the dorsal system facilitates continuous regulation of action. This dual-system model implies that empirically manipulating different visual information sources during performance of an interceptive action might lead to the emergence of distinct gaze and movement pattern profiles. To test this idea, we recorded hand kinematics and eye movements of participants as they attempted to catch balls projected from a novel apparatus that synchronised or de-synchronised accompanying video images of a throwing action and ball trajectory. Results revealed that ball catching performance was less successful when patterns of hand movements and gaze behaviours were constrained by the absence of advanced perceptual information from the thrower's actions. Under these task constraints, participants began tracking the ball later, followed less of its trajectory, and adapted their actions by initiating movements later and moving the hand faster. There were no performance differences when the throwing action image and ball speed were synchronised or de-synchronised since hand movements were closely linked to information from ball trajectory. Results are interpreted relative to the two-visual system hypothesis, demonstrating that accurate interception requires integration of advanced visual information from kinematics of the throwing action and from ball flight trajectory.

Putting an "end" to the motor cortex representations of action words

Language processing is an example of implicit learning of multiple statistical cues that provide probabilistic information regarding word structure and use. Much of the current debate about language embodiment is devoted to how action words are represented in the brain, with motor cortex activity evoked by these words assumed to selectively reflect conceptual content and/or its simulation. We investigated whether motor cortex activity evoked by manual action words (e.g., caress) might reflect sensitivity to probabilistic orthographic-phonological cues to grammatical category embedded within individual words. We first review neuroimaging data demonstrating that nonwords evoke activity much more reliably than action words along the entire motor strip, encompassing regions proposed to be action category specific. Using fMRI, we found that disyllabic words denoting manual actions evoked increased motor cortex activity compared with non-body-part-related words (e.g., canyon), activity which overlaps that evoked by observing and executing hand movements. This result is typically interpreted in support of language embodiment. Crucially, we also found that disyllabic nonwords containing endings with probabilistic cues predictive of verb status (e.g., -eve) evoked increased activity compared with nonwords with endings predictive of noun status (e.g., -age) in the identical motor area. Thus, motor cortex responses to action words cannot be assumed to selectively reflect conceptual content and/or its simulation. Our results clearly demonstrate motor cortex activity reflects implicit processing of ortho-phonological statistical regularities that help to distinguish a word's grammatical class.

The use of visual analogue scales to assess motivation to eat in human subjects: a review of their reliability and validity with an evaluation of new hand-held computerized stsytems for temporal tracking of appetite ratings.

This present paper reviews the reliability and validity of visual analogue scales (VAS) in terms of (1) their ability to predict feeding behaviour, (2) their sensitivity to experimental manipulations, and (3) their reproducibility. VAS correlate with, but do not reliably predict, energy intake to the extent that they could be used as a proxy of energy intake. They do predict meal initiation in subjects eating their normal diets in their normal environment. Under laboratory conditions, subjectively rated motivation to eat using VAS is sensitive to experimental manipulations and has been found to be reproducible in relation to those experimental regimens. Other work has found them not to be reproducible in relation to repeated protocols. On balance, it would appear, in as much as it is possible to quantify, that VAS exhibit a good degree of within-subject reliability and validity in that they predict with reasonable certainty, meal initiation and amount eaten, and are sensitive to experimental manipulations. This reliability and validity appears more pronounced under the controlled (but more arti®cial) conditions of the laboratory where the signal : noise ratio in experiments appears to be elevated relative to real life. It appears that VAS are best used in within-subject, repeated-measures designs where the effect of different treatments can be compared under similar circumstances. They are best used in conjunction with other measures (e.g. feeding behaviour, changes in plasma metabolites) rather than as proxies for these variables. New hand-held electronic appetite rating systems (EARS) have been developed to increase reliability of data capture and decrease investigator workload. Recent studies have compared these with traditional pen and paper (P&P) VAS. The EARS have been found to be sensitive to experimental manipulations and reproducible relative to P&P. However, subjects appear to exhibit a signi®cantly more constrained use of the scale when using the EARS relative to the P&P. For this reason it is recommended that the two techniques are not used interchangeably

Elucidating the host-pathogen interactions between in vitro human cells and enterovirus 71 in Hand, Foot and Mouth Disease (HFMD)

This study has provided further understanding of the pathogenesis of EV71, one of the major etiological agents associated with significant mortality in Hand, Foot and Mouth disease. Elucidating the host-pathogen interaction and the mechanism that the virus uses to bypass host defence systems to establish infection will aid in the development of potential antiviral therapeutics against EV71.

Work at hand : an exploration of gesture in the context of work and everyday life to inform the design of gestural input devices

This research explores gestures used in the context of activities in the workplace and in everyday life in order to understand requirements and devise concepts for the design of gestural information applicances. A collaborative method of video interaction analysis devised to suit design explorations, the Video Card Game, was used to capture and analyse how gesture is used in the context of six different domains: the dentist's office; PDA and mobile phone use; the experimental biologist's laboratory; a city ferry service; a video cassette player repair shop; and a factory flowmeter assembly station. Findings are presented in the form of gestural themes, derived from the tradition of qualitative analysis but bearing some similarity to Alexandrian patterns. Implications for the design of gestural devices are discussed.

Movements in gesture interfaces

There is a mismatch between the kinds of movements used in gesture interfaces and our existing theoretical understandings of gesture. We need to re-examine the assumptions of gesture research and develop theory more suited to gesture interface design. In addition to improved theory, we need to develop ways for participants in the process of design to adapt, extend and develop theory for their own design contexts. Gesture interface designers should approach theory as a contingent resource for design actions that is responsive to the needs of the design process.

Social justice and high-quality human services : visioning the place of a contemporary professional association

The current world situation is plagued by “wicked problems” and a widespread sense of “things are going to get worse”. We confront the almost imponderable consequences of global habitat destruction and climate change, as well as the meltdown of the financial markets with their largely yet to be seen damage to the “real economy”. These things will have considerable negative impacts on the social system and people's lives, particularly the disadvantaged and socially excluded, and require innovative policy and program responses delivered by caring, intelligent, and committed practitioners. These gargantuan issues put into perspective the difficulties that confront social, welfare, and community work today. Yet, in times of trouble, social work and human services tend to do well. For example, although Australian Social Workers and Welfare and Community Workers have experienced phenomenal job growth over the past 5 years, they also have good prospects for future growth and above average salaries in the seventh and sixth deciles, respectively (Department of Education, Employment and Workplace Relations, 2008). I aim to examine the host of reasons why the pursuit of social justice and high-quality human services is difficult to attain in today's world and then consider how the broadly defined profession of social welfare practitioners may collectively take action to (a) respond in ways that reassert our role in compassionately assisting the downtrodden and (b) reclaim the capacity to be a significant body of professional expertise driving social policy and programs. For too long social work has responded to the wider factors it confronts through a combination of ignoring them, critiquing from a distance, and concentrating on the job at hand and our day-to-day responsibilities. Unfortunately, “holding the line” has proved futile and, little by little, the broad social mandate and role of social welfare has altered until, currently, most social programs entail significant social surveillance of troublesome or dangerous groups, rather than assistance. At times it almost seems like the word “help” has been lost in the political and managerial lexicon, replaced by “manage” and “control”. Our values, beliefs, and ethics are under real threat as guiding principles for social programs.

Automating human thought processes for a UAV forced landing

This paper describes the current status of a program to develop an automated forced landing system for a fixed-wing Unmanned Aerial Vehicle (UAV). This automated system seeks to emulate human pilot thought processes when planning for and conducting an engine-off emergency landing. Firstly, a path planning algorithm that extends Dubins curves to 3D space is presented. This planning element is then combined with a nonlinear guidance and control logic, and simulated test results demonstrate the robustness of this approach to strong winds during a glided descent. The average path deviation errors incurred are comparable to or even better than that of manned, powered aircraft. Secondly, a study into suitable multi-criteria decision making approaches and the problems that confront the decision-maker is presented. From this study, it is believed that decision processes that utilize human expert knowledge and fuzzy logic reasoning are most suited to the problem at hand, and further investigations will be conducted to identify the particular technique/s to be implemented in simulations and field tests. The automated UAV forced landing approach presented in this paper is promising, and will allow the progression of this technology from the development and simulation stages through to a prototype system

Near-infrared spectroscopic studies of human scalp hair in a forensic context

Human hair is a relatively inert biopolymer and can survive through natural disasters. It is also found as trace evidence at crime scenes. Previous studies by FTIRMicrospectroscopy and – Attenuated Total Reflectance (ATR) successfully showed that hairs can be matched and discriminated on the basis of gender, race and hair treatment, when interpreted by chemometrics. However, these spectroscopic techniques are difficult to operate at- or on-field. On the other hand, some near infrared spectroscopic (NIRS) instruments equipped with an optical probe, are portable and thus, facilitate the on- or at –field measurements for potential application directly at a crime or disaster scene. This thesis is focused on bulk hair samples, which are free of their roots, and thus, independent of potential DNA contribution for identification. It explores the building of a profile of an individual with the use of the NIRS technique on the basis of information on gender, race and treated hair, i.e. variables which can match and discriminate individuals. The complex spectra collected may be compared and interpreted with the use of chemometrics. These methods can then be used as protocol for further investigations. Water is a common substance present at forensic scenes e.g. at home in a bath, in the swimming pool; it is also common outdoors in the sea, river, dam, puddles and especially during DVI incidents at the seashore after a tsunami. For this reason, the matching and discrimination of bulk hair samples after the water immersion treatment was also explored. Through this research, it was found that Near Infrared Spectroscopy, with the use of an optical probe, has successfully matched and discriminated bulk hair samples to build a profile for the possible application to a crime or disaster scene. Through the interpretation of Chemometrics, such characteristics included Gender and Race. A novel approach was to measure the spectra not only in the usual NIR range (4000 – 7500 cm-1) but also in the Visible NIR (7500 – 12800 cm-1). This proved to be particularly useful in exploring the discrimination of differently coloured hair, e.g. naturally coloured, bleached or dyed. The NIR region is sensitive to molecular vibrations of the hair fibre structure as well as that of the dyes and damage from bleaching. But the Visible NIR region preferentially responds to the natural colourants, the melanin, which involves electronic transitions. This approach was shown to provide improved discrimination between dyed and untreated hair. This thesis is an extensive study of the application of NIRS with the aid of chemometrics, for matching and discrimination of bulk human scalp hair. The work not only indicates the strong potential of this technique in this field but also breaks new ground with the exploration of the use of the NIR and Visible NIR ranges for spectral sampling. It also develops methods for measuring spectra from hair which has been immersed in different water media (sea, river and dam)

A critical analysis of sperm donation practices : the personal and social effects of disrupting the unity of biological and social relatedness for the offspring

This thesis critically analyses sperm donation practices from a child-centred perspective. It examines the effects, both personal and social, of disrupting the unity of biological and social relatedness in families affected by donor conception. It examines how disruption is facilitated by a process of mediation which is detailed using a model provided by Sunderland (2002). This model identifies mediating movements - alienation, translation, re-contextualisation and absorption - which help to explain the powerful and dominating material, and social and political processes which occur in biotechnology, or in reproductive technology in this case. The understanding of such movements and mediation of meanings is inspired by the complementary work of Silverstone (1999) and Sunderland. This model allows for a more critical appreciation of the movement of meaning from previously inalienable aspects of life to alienable products through biotechnology (Sunderland, 2002). Once this mediation in donor conception is subjected to critical examination here, it is then approached from different angles of investigation. The thesis posits that two conflicting notions of the self are being applied to fertility-frustrated adults and the offspring of reproductive interventions. Adults using reproductive interventions receive support to maximise their genetic continuity, but in so doing they create and dismiss the corresponding genetic discontinuity produced for the offspring. The offspring’s kinship and identity are then framed through an experimental postmodernist notion, presenting them as social rather than innate constructs. The adults using the reproductive intervention, on the other hand, have their identity and kinship continuity framed and supported as normative, innate, and based on genetic connection. This use of shifting frameworks is presented as unjust and harmful, creating double standards and a corrosion of kinship values, connection and intelligibility between generations; indeed, it is put forward as adult-centric. The analysis of other forms of human kinship dislocation provided by this thesis explores an under-utilised resource which is used to counter the commonly held opinion that any disruption of social and genetic relatedness for donor offspring is insignificant. The experiences of adoption and the stolen generations are used to inform understanding of the personal and social effects of such kinship disruption and potential reunion for donor offspring. These examples, along with laws governing international human rights, further strengthen the appeal here for normative principles and protections based on collective knowledge and standards to be applied to children of reproductive technology. The thesis presents the argument that the framing and regulation of reproductive technology is excessively influenced by industry providers and users. The interests of these parties collide with and corrode any accurate assessments and protections afforded to the children of reproductive technology. The thesis seeks to counter such encroachments and concludes by presenting these protections, frameworks, and human experiences as resources which can help to address the problems created for the offspring of such reproductive interventions, thereby illustrating why these reproductive interventions should be discontinued.

Contributions of vision-proprioception interactions to the estimation of time-varying hand and target locations

We investigated the relative importance of vision and proprioception in estimating target and hand locations in a dynamic environment. Subjects performed a position estimation task in which a target moved horizontally on a screen at a constant velocity and then disappeared. They were asked to estimate the position of the invisible target under two conditions: passively observing and manually tracking. The tracking trials included three visual conditions with a cursor representing the hand position: always visible, disappearing simultaneously with target disappearance, and always invisible. The target’s invisible displacement was systematically underestimated during passive observation. In active conditions, tracking with the visible cursor significantly decreased the extent of underestimation. Tracking of the invisible target became much more accurate under this condition and was not affected by cursor disappearance. In a second experiment, subjects were asked to judge the position of their unseen hand instead of the target during tracking movements. Invisible hand displacements were also underestimated when compared with the actual displacement. Continuous or brief presentation of the cursor reduced the extent of underestimation. These results suggest that vision–proprioception interactions are critical for representing exact target–hand spatial relationships, and that such sensorimotor representation of hand kinematics serves a cognitive function in predicting target position. We propose a hypothesis that the central nervous system can utilize information derived from proprioception and/or efference copy for sensorimotor prediction of dynamic target and hand positions, but that effective use of this information for conscious estimation requires that it be presented in a form that corresponds to that used for the estimations.

The relationship of boat movements to environmental management at some Queensland marinas

Marinas currently exist primarily to service recreational boats, and these vessels are a potential cause of both problems and opportunities in environmental management. Thus, on the one hand, destructive fuel and other pollutants may be expelled, boat wakes can cause littoral soil erosion, physical damage results from collisions with marine life, and litter and noise pollution occur in otherwise pristine habitat. Boats also provide access to otherwise inaccessible natural environments for educational and other management reasons. In this study, boat traffic at three large marinas located along the Queensland coastline has been field surveyed for introductory information. No attempt was made at this juncture to survey the behaviour of the boat crews and passengers (concerning actual destinations, activities on board, etc. or to survey the recreational boat industry. Such studies rely on boat registration records and personal questionnaires. Some other surveys relating to fishing draw on boat ramp surveys and direct submissions by recreational fishers; these provide some data on daily usage of boat ramps, but without particular attention to boats. We believe field observations of overall boat activities in the water are necessary for environmental management purposes. The aim of the survey was to provide information to help prioritize the potential impacts that boats’ activities have on the surrounding natural environment. Any impact by boats will be a product of their numbers, size, frequency of movement, carrying capacity and routes/destinations. The severity of impacts will dictate the appropriate management action.