Digital Video Footage Research Articles

Influence of unilateral and bilateral vocal cordectomy on airflow across cadaveric equine larynges at different Rakestraw grades of arytenoid abduction.

ObjectiveTo assess the effect of vocal cordectomy on airflow across equine larynges at different Rakestraw grades of arytenoid abduction using a unidirectional airflow model.Study designEx vivo, repeated measures.Sample populationTwenty cadaveric equine larynges.MethodsThe right arytenoid cartilage was maximally abducted in all larynges. Each larynx was assigned a Rakestraw grade A or B, and the left arytenoid was abducted accordingly. Each larynx was tested under 3 conditions: intact, left vocal cordectomy (LVC), and bilateral vocal cordectomy (BVC). Translaryngeal pressure and airflow were measured, and digital video footage was obtained. Translaryngeal impedance (TLI) was calculated, and the arytenoid left‐to‐right quotient angle (LRQ) and rima glottis cross‐sectional area (CSA) were measured from standardized still images.ResultsVocal cordectomy reduced TLI by 14.5% in LVC in comparison with intact larynges at Rakestraw grade B (P = .014). In Rakestraw grade A position, neither unilateral nor bilateral vocal cordectomy had any effect on TLI. Regardless of Rakestraw allocation, both LVC and BVC increased CSA in comparison with intact larynges (P < .005), with BVC larynges experiencing a greater effect than LVC (P < .0001).ConclusionUsing a unilateral airflow model, LVC improved TLI in larynges where arytenoid position approximated Rakestraw grade B. However, when the arytenoid position approximated Rakestraw grade A, there was no effect on TLI following LVC or BVC.Clinical significanceSurgeons considering a vocal cordectomy should take into account the degree of arytenoid abduction before performing the procedure, as it may not be warranted from a TLI point of view.

Video-based self-reflection among pre-service teachers in Ireland: A qualitative study

With increased accessibility to digital video equipment, there has been notable interest in exploring how this might support practice and pedagogy across many education sectors. In recent years video has been found to offer many opportunities to study and support teacher professional development. This paper examines the potential for digital observation within initial teacher education (ITE), specifically as a tool for engaging pre-service teachers in reflective practice during school placement. The study included pre-service primary teachers in the largest teacher education centre in Ireland. A treatment group (n = 15) completed their compulsory written reflections as normal during school placement but were also provided with Swivl digital technology in order to record and reflect on their lessons using video footage. A control group (n = 20) completed their traditional written reflections as normal without the use of the digital technology. Upon the completion of school placement, in-depth qualitative interviews with both treatment and control groups (N = 35) examined experiences in using digital technologies in the classroom, and the critical reflection of their lessons during school placement. The analysis provides strong evidence that the digital video footage was highly supportive in pre-service teachers’ weekly self-reflection and in developing their self-reflective practice. They reflected on embodied and non-embodied aspects of their teaching, in the process revising their habitus as a teacher. The richness of the data provides new evidence on the potential for video technology to support teacher professional development internationally.

The Influence of a Goalkeeper as an Outfield Player on Defensive Subsystems in Futsal

The aim of this study was to investigate the influence of the goalkeeper as an outfield player on defensive subsystems in the team sport of futsal. For this purpose, all sequences of play involving the goalkeeper (n = 65), and the sequences without a goalkeeper (controls) (n = 11), were selected from digital video footage of a futsal competition, and analysed using TACTO software. The defensive area, attacker-defender distance, and interception distance were used to examine players’ coordination tendencies as a team in completion of successful and unsuccessful passes and shots. Results showed that each team reduced its defensive area as well as its variability in situations where the goalkeeper acted as an outfield player. This finding implies that it was an effective defensive strategy because it led to emergence of more unsuccessful passes. It was also observed that the goalkeeper acting as an outfield player was an effective strategy for attacking in terms of increasing shots at goal.

Qualitative Real-Time Schlieren and Shadowgraph Imaging of Human Exhaled Airflows: An Aid to Aerosol Infection Control

Using a newly constructed airflow imaging system, airflow patterns were visualized that were associated with common, everyday respiratory activities (e.g. breathing, talking, laughing, whistling). The effectiveness of various interventions (e.g. putting hands and tissues across the mouth and nose) to reduce the potential transmission of airborne infection, whilst coughing and sneezing, were also investigated. From the digital video footage recorded, it was seen that both coughing and sneezing are relatively poorly contained by commonly used configurations of single-handed shielding maneuvers. Only some but not all of the forward momentum of the cough and sneeze puffs are curtailed with various hand techniques, and the remaining momentum is disseminated in a large puff in the immediate vicinity of the cougher, which may still act as a nearby source of infection. The use of a tissue (in this case, 4-ply, opened and ready in the hand) proved to be surprisingly effective, though the effectiveness of this depends on the tissue remaining intact and not ripping apart. Interestingly, the use of a novel ‘coughcatcher’ device appears to be relatively effective in containing coughs and sneezes. One aspect that became evident during the experimental procedures was that the effectiveness of all of these barrier interventions is very much dependent on the speed with which the user can put them into position to cover the mouth and nose effectively.From these qualitative schlieren and shadowgraph imaging experiments, it is clear that making some effort to contain one's cough or sneeze puffs is worthwhile. Obviously, there will be a large amount of variation between individuals in the exact hand or tissue (the most common methods) configuration used for this and other practical factors may hinder such maneuvers in daily life, for example, when carrying shopping bags or managing young children.

Caffeine and performance in clay target shooting

Controversy surrounds the influence that caffeine has on accuracy and cognitive performance in precision activities such as shooting and archery. The aim of this study was to assess the effects of two doses of caffeine on shooting performance, reaction time, and target tracking times in the sport of clay target shooting. A randomized, double-blind, placebo-controlled design was undertaken by seven elite male shooters from the double-trap discipline. Three intervention trials (2 mg caffeine · kg−1 body mass (BM); 4 mg caffeine · kg−1 BM; placebo) were undertaken, in which shooters completed four rounds per trial of 50 targets per round. Performance accuracy (score) and digital video footage (for determination of reaction time and target tracking times) were gathered during competition. Data were analysed using repeated-measures analysis of variance. No differences in shooting accuracy, reaction time or target tracking times among the three intervention trials or across the four rounds within each intervention were observed (P > 0.05). The results indicate that ingestion of ≤4 mg caffeine · kg−1 BM does not provide performance benefits to elite performers of clay target shooting in the double-trap discipline.

Double blind investigation of the effects of oral supplementation of combined glucosamine hydrochloride (GHCL) and chondroitin sulphate (CS) on stride characteristics of veteran horses

Oral chondroprotective supplements are commercially popular for veteran (and other athletic or arthritic) horses prone to joint degeneration, yet lack conclusive scientific support. To quantify the effects of an oral joint supplement (combination glucosamine hydrochloride (GHCL), chondroitin sulphate (CS) and N-acetyl-D-glucosamine) in vivo on stride parameters of veteran horses. Twenty veteran horses were randomly assigned to a treatment (n = 15) or placebo group (n = 5). Pre-treatment gait characteristics were recorded at trot using digital video footage (50 Hz). The range of joint motion, stride length, and swing and stance duration were assessed using 2-dimensional motion analysis. Treatment (or placebo) was administered daily for 12 weeks at the manufacturer's recommended dosage. Gait was reassessed every 4 weeks using the pre-treatment protocol. Double blind procedure was implemented throughout. Relationships between variables were analysed using General Linear Model. Differences occurred in the treated horses by week 8. Range of joint motion increased significantly in the elbow (P<0.05), stifle and hind fetlock (P<0.01). Stride length increased significantly (P<0.05) with treatment. Swing duration was significantly increased at week 12 (P<0.05), whilst stance duration remained constant. The oral chondroprotective offered symptomatic relief to veteran horses, evidenced by improved stride characteristics. Oral GHCL and CS supplementation may improve welfare by alleviating symptoms of degenerative joint disease.

High-level virtual reality simulator for endourologic procedures of lower urinary tract

Objectives To analyze the limitations of existing simulators for urologic techniques, and then test and evaluate a novel virtual reality (VR) simulator for endourologic procedures of the lower urinary tract. Surgical simulation using VR has the potential to have a tremendous impact on surgical training, testing, and certification. Endourologic procedures seem to be an ideal target for VR systems. Methods The URO-Trainer features genuine VR, obtained from digital video footage of more than 400 endourologic diagnostic and therapeutic procedures, as well as data from cross-sectional imaging. The software offers infinite random variations of the anatomy and pathologic features for diagnosis and surgical intervention. An advanced haptic force feedback is incorporated. Virtual cystoscopy and resection of bladder tumors were evaluated by 24 medical students and 12 residents at our department. Results The system was assessed by more than 150 international urologists with varying experience at different conventions and workshops from March 2003 to September 2004. Because of these evaluations and constant evolutions, the final version provides a genuine representation of endourologic procedures. Objective data are generated by a tutoring system that has documented evident teaching benefits for medical students and residents in cystoscopy and treatment of bladder tumors. Conclusions The URO-Trainer represents the latest generation of endoscopy simulators. Authentic visual and haptic sensations, unlimited virtual cases, and an intelligent tutoring system make this modular system an important improvement in computer-based training and quality control in urology.

Taming the Barking Dog

This demonstration brings Liebig's famous 19th-century demonstration headlong into the 21st century, using digital video footage and other novel media. We describe how to effectively carry out the reaction in a classroom situation and show how the Barking Dog reaction can be used to illustrate various principles of physical chemistry.

The imagination of construction

The second half of the presentation details a recently completed learning and teaching project at the University of Adelaide that developed a Video Site Visit using digital video footage. The VSV consists of approximately 450 video clips that show most phases of the building of an architecturally designed house in suburban Adelaide. The primary aim of the Video Site is to provide a means of engaging students of architecture in the relationship between construction and design that would normally be assigned to the physical site visit. This was a response, in part, to the increasing difficulty of getting large numbers of students onto building sites. The VSV is not intended to replace actual site visits but does allow other possibilities that are otherwise very difficult. For example, a student may follow the construction of a building from beginning to end should this be required as part of a construction assignment.

Evaluation of a two dimensional analysis method as a screening and evaluation tool for anterior cruciate ligament injury

Background: Increased knee valgus predicts the risk of anterior cruciate ligament (ACL) injury, particularly in women. Reducing injury rates thus relies on detecting and continually evaluating people with relatively large...

Borehole imagery of meteoric and marine ice layers in the Amery Ice Shelf, East Antarctica

AbstractA real-time video camera probe was deployed in a hot-water drilled borehole through the Amery Ice Shelf, East Antarctica, where a total ice thickness of 480 m included at least 200 m of basal marine ice. Down-looking and side-looking digital video footage showed a striking transition from white bubbly meteoric ice above to dark marine ice below, but the transition was neither microscopically sharp nor flat, indicating the uneven nature (at centimetre scale) of the ice-shelf base upstream where the marine ice first started to accrete. Marine ice features were imaged including platelet structures, cell inclusions, entrained particles, and the interface with sea water at the base. The cells are assumed to be entrained sea water, and were present throughout the lower 100-150 m of the marine ice column, becoming larger and more prevalent as the lower surface was approached until, near the base, they became channels large enough that the camera field of view could not contain them. Platelets in the marine ice at depth appeared to be as large as 1-2 cm in diameter. Particles were visible in the borehole meltwater; probably marine and mineral particles liberated by the drill, but their distribution varied with depth.