What is Seen, What is Said to be Seen: Exploring Doubt as a Critical Tool within Artists' Moving Image Practice

Doubt is a loaded word. There are associations and histories that weave the word through theological, philosophical, political, legal and psychoanalytic thought. It is entangled. However, it is precisely because of the complexity and ambiguity of the term doubt that it holds my interest. The associative relationships that doubt has with truth, proof, faith, belief, testimony, witnessing, fact and fiction are all active components in my practice and research. There are three artworks that act as case studies that explore these relationships: a single screen video (April, 2018), a video performance (The Narrator, 2018) and a video installation with accompanying performance (The Unreliable Narrator, 2019). The written thesis is a reflective text that is structured around the description and analysis of these three artworks. While acknowledging existing studies that examine the generative potential of doubt or ‘not knowing’ within creative processes (Cocker, 2013; Herbert, 2014), the aim of my research is to investigate the critical potential of doubt when made manifest within an artwork, as an attribute or affect. To do this, my practice-led research pursues doubt as both its subject and as a consequence of the work itself. The latter approach (as consequence or affect) positions doubt as a cognitive or sensory experience that may be produced in a viewer by way of the work. There are various structural methods that I have explored to achieve this, for example the use of repetition in narrative or filmic loops that can be seen in my single screen film April (2018) and video performance The Narrator (2018). My investigation of doubt as content is evidenced most explicitly in my video performance The Narrator that asks: what if you knew no doubt, held no inconsistencies, had no contradictory thoughts, feelings or urges? By putting these questions into play, The Narrator entertains the improbable, perhaps impossible, notion of a narrator whose reliability is absolute. However, What is Seen, What is Said to be Seen also considers the one who sees and what they say they saw. Prophetic sight and stage magic are the subjects central to April and The Unreliable Narrator respectively; both present moments of uncertain seeing that sit close to the limits of vision and perception and it is this uncertain seeing that the artworks attempt to reenact

Site-Specific Risk Factors for Ray Blight in Tasmanian Pyrethrum Fields

Ray blight of pyrethrum (Tanacetum cinerariifolium), caused by Phoma ligulicola var. inoxydablis, can cause defoliation and reductions of crop growth and pyrethrin yield. Logistic regression was used to model relationships among edaphic factors and interpolated weather variables associated with severe disease outbreaks (i.e., defoliation severity ≥40%). A model for September defoliation severity included a variable for the product of number of days with rain of at least 0.1 mm and a moving average of maximum temperatures in the last 14 days, which correctly classified (accuracy) the disease severity class for 64.8% of data sets. The percentage of data sets where disease severity was correctly classified as at least 40% defoliation severity (sensitivity) or below 40% defoliation severity (specificity) were 55.8 and 71%, respectively. A model for October defoliation severity included the number of days with at least 1 mm of rain in the past 14 days, stem height in September, and the product of the number of days with at least 10 mm of rain in the last 30 days and September defoliation severity. Accuracy, sensitivity, and specificity were 72.6, 73.6, and 71.4%, respectively. Youden\u27s index identified predictive thresholds of 0.25 and 0.57 for the September and October models, respectively. When economic considerations of the costs of false positive and false negative decisions and disease prevalence were integrated into receiver operating characteristic (ROC) curves for the October model, the optimal predictive threshold to minimize average management costs was 0 for values of disease prevalence greater than 0.2 due to the high cost of false negative predictions. ROC curve analysis indicated that management of the disease should be routine when disease prevalence is greater than 0.2. The models developed in this research are the first steps toward identifying and weighting site and weather disease risk variables to develop a decision-support aid for the management of ray blight of pyrethrum

Diseases of Pyrethrum in Tasmania: Challenges and Prospects for Management

Pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.) is a perennial plant and member of the Asteraceae that is endemic to the Dalmatian region of the former Yugoslavia (36). Pyrethrum is cultivated commercially solely for the production of six closely related esters called pyrethrins. The plant is tufted, slender, and herbaceous, growing to a height of approximately one meter (18). Leaves are alternate and pinnately lobed/narrowly lanceolate to oblong lanceolate. The daisy-like flowers are produced at the termini of stems and consist of a cluster of 40 to 100 bisexual, yellow disk florets encircled by a ring of 18 to 22 pistillate white ray florets atop a moderately convex to subglobose receptacle (Fig. 1; 100). Disk and ray florets both possess 3 to 10 ribbed achenes located between the floret and receptacle. Involucres generally range between 12 and 18 mm in diameter (17,18). Approximately 94% o

A Systematic Review of Center of Mass as a Measure of Dynamic Postural Control Following Concussion

BACKGROUND: The incidence of sports-related concussion in the US is between 1.6-3.8 million annually. Identification of ongoing impairment post-concussion continues to be challenging, as research indicates many patients are cleared for return to activity while still suffering subclinical impairment of function. Purpose: To identify and review the current literature on the use of center of mass (COM) during gait as a potential indicator variable after concussive injury. Study Design: Systematic Review. METHODS: A Pubmed search was undertaken utilizing search terms involving gait performance and concussion. Study inclusion criteria included: (1) COM used as a variable in data analysis, (2) study population included individuals diagnosed with concussion, (3) postural control was evaluated throughout the recovery process. Articles were excluded if they were systematic reviews, unedited manuscripts, meta-analyses, or were more than 15 years old. RESULTS: Search of the PubMed database identified six articles which matched the determined criteria. The average STROBE score was 26.5/34 (range from 23-30). The areas that had the poorest scoring were bias, study size, statistical methods, participants, descriptive data, and main results. Results of the review indicate that COM displacement was higher in concussion groups with a sufficiently taxing task, such as a dual task paradigm. CONCLUSION: Center of mass measures during gait may be an indicator of ongoing concussive injury involvement after clinical indications have subsided. LEVEL OF EVIDENCE: 2a

Can activities of daily living contribute to EMG normalization for gait analysis?

This study aims to examine alternative methods of normalization that effectively reflect muscle activity as compared to Maximal Voluntary Contraction (MVC). EMG data recorded from knee flexion-extension muscles in 10 control subjects during the stance phase of the gait cycle were examined by adopting different approaches of normalization: MVC, Mean and Peak Dynamic during gait cycles, (MDM and PDM, respectively), Peak Dynamic during activities of daily living (ADLs), (*PDM), and a combination of ADLs and MVC(**PDM). Intra- and inter-individual variability were calculated to determine reliability and similarity to MCV. **PDM showed excellent reliability across subjects in comparison to MVC, where variance ratio ranged from 0.43–0.99 for **PDM and 0.79–1.08 for MVC. Coefficient of variability showed a similar trend to Variance Ratio, ranging from 0.60–1.25 for **PDM and 1.97– 3.92 for MVC. Both MVC and **PDM, and to some extent *PDM, demonstrated good-toexcellent relative amplitude’s matching; i.e. root mean square difference and absolute difference were both around 0.08 for Vastus medialis to about 4 for Medial gastrocnemius. It was concluded that **PDM and *PDM were reliable, **PDM mirrored MVC and thus could be used as an alternative to MVC for subjects who are unable to provide the required effort for MVC testing. Where MVC testing is not possible, *PDM is the next preferred option

A Dual X-Ray Absorptiometry Validated Geometric Model for the Calculation of Body Segment Inertial Parameters of Young Females

The purpose of this study was to validate a new geometric solids model, developed to address the lack of female specific models for body segment inertial parameter estimation. A second aim was to determine the effect of reducing the number of geometric solids used to model the limb segments on model accuracy. The ‘full’ model comprised 56 geometric solids, the ‘reduced’ 31, and the ‘basic’ 16. Predicted whole-body inertial parameters were compared with direct measurements (reaction board, scales), and predicted segmental parameters with those estimated from whole-body DXA scans for 28 females. The percentage root mean square error (%RMSE) for whole-body volume was <2.5% for all models, and 1.9% for the full model. The %RMSE for whole-body center of mass location was <3.2% for all models. The %RMSE whole-body mass was <3.3% for the full model. The RMSE for segment masses was <0.5 kg (<0.5%) for all segments; Bland-Altman analysis showed the full and reduced models could adequately model thigh, forearm, foot and hand segments, but the full model was required for the trunk segment. The proposed model was able to accurately predict body segment inertial parameters for females, more geometric solids are required to more accurately model the trunk