Characterization of Carbon-Contaminated B4C-Coated Optics after Chemically Selective Cleaning with Low-Pressure RF Plasma

Boron carbide (B4C) is one of the few materials that is expected to be mostly resilient with respect to the extremely high brilliance of the photon beam generated by free electron lasers (FELs) and is thus of considerable interest for optical applications in this field. However, as in the case of many other optics operated at modern light source facilities, B4C-coated optics are subject to ubiquitous carbon contaminations. These contaminations represent a serious issue for the operation of high performance FEL beamlines due to severe reduction of photon flux, beam coherence, creation of destructive interference, and scattering losses. A variety of B4C cleaning technologies were developed at different laboratories with varying success. We present a study regarding the low-pressure RF plasma cleaning of carbon contaminated B4C test samples via inductively coupled O2/Ar, H2/Ar, and pure O2 RF plasma produced following previous studies using the same IBSS GV10x downstream plasma source. Results regarding the chemistry, morphology as well as other aspects of the B4C optical coating before and after the plasma cleaning are reported. We conclude from these comparative plasma processes that pure O2 feedstock plasma only exhibits the required chemical selectivity for maintaining the integrity of the B4C optical coating.Comment: 27 pages, 15 figure

Access and outcomes of general practitioner obstetrician (rural generalist)-supported birthing units in Queensland

Funding Information Queensland Rural Generalist PathwayPeer reviewedPublisher PD

Localization of Interaction using Fibre-Optic Shape Sensing in Soft-Robotic Surgery Tools

Minimally invasive surgery requires real-time tool tracking to guide the surgeon where depth perception and visual occlusion present navigational challenges. Although vision-based and external sensor-based tracking methods exist, fibre-optic sensing can overcome their limitations as they can be integrated directly into the device, are biocompatible, small, robust and geometrically versatile. In this paper, we integrate a fibre Bragg grating-based shape sensor into a soft robotic device. The soft robot is the pneumatically attachable flexible (PAF) rail designed to act as a soft interface between manipulation tools and intra-operative imaging devices. We demonstrate that the shape sensing fibre can detect the location of the tools paired with the PAF rail, by exploiting the change in curvature sensed by the fibre when a strain is applied to it. We then validate this with a series of grasping tasks and continuous US swipes, using the system to detect in real-time the location of the tools interacting with the PAF rail. The overall location-sensing accuracy of the system is 64.6%, with a margin of error between predicted location and actual location of 3.75 mm

The Impact of Active Learning in a Speech-Language Pathology Swallowing and Dysphagia Course

The signature pedagogy in Speech-Language Pathology (SLP) higher education programs has been criticized for its instructor-centric lecture format and emphasis on the lower tiers of Bloom’s taxonomy (simply memorizing knowledge) at the expense of helping students develop the clinical problem-solving skills required for a lifetime of practice and learning. The purpose of this study was to examine the responses of a cohort of graduate speech-language pathology students to an active learning-oriented swallowing and dysphagia course design. A potential relationship between student perceptions of the active learning pedagogy and academic performance was also explored. The results suggest that active learning positively impacted both student perceptions and performance in the redesigned swallowing and dysphagia course

Taste Manipulation and Swallowing Mechanics in Trauma-Related Sensory-Based Dysphagia

Purpose: This study explored the effects of highconcentration taste manipulation trials on swallow function in persons with sensory-based dysphagia. Method: Dysphagia researchers partnered with clinical providers to prospectively identify traumatically injured U.S. military service members (N = 18) with sensorybased dysphagia as evidenced by delayed initiation and/or decreased awareness of residue/penetration/ aspiration. Under videofluoroscopy, participants swallowed trials of 3 custom-mixed taste stimuli: unflavored (40% weight/volume [wt/vol] barium sulfate in distilled water), sour (2.7%wt/vol citric acid in 40% wt/vol barium suspension), and sweet–sour (1.11% wt/vol citric acid plus 8% wt/vol sucrose in 40% wt/vol barium suspension). Trials were analyzed and compared via clinical rating tools (the Modified Barium Swallow Impairment Profile [Martin-Harris et al., 2008] and the Penetration-Aspiration Scale [Rosenbek, Robbins, Roecker, Coyle, & Wood, 1996]). Additionally, a computational analysis of swallowing mechanics (CASM) was applied to a subset of 9 swallows representing all 3 tastants from 3 participants. Results: Friedman’s tests for the 3 stimuli revealed significantly (p \u3c .05) improved functional ratings for Penetration-Aspiration Scale and pharyngoesophageal opening. CASM indicated differences in pharyngeal swallowing mechanics across all tastant comparisons (p ≤ .0001). Eigenvectors revealed increased tongue base retraction, hyoid elevation, and pharyngeal shortening for sweet–sour and, to a lesser extent, sour than for unflavored boluses. Conclusion: Advantageous changes in certain parameters of oropharyngeal swallowing physiology were noted with high-intensity tastants per both clinical ratings and subsequent CASM, suggesting potential therapeutic application for taste manipulation

Dysphagia Management and Research in an Acute-Care Military Treatment Facility: The Role of Applied Informatics

Purpose: This report describes the development and preliminary analysis of a database for traumatically injured military service members with dysphagia. Methods: A multidimensional database was developed to capture clinical variables related to swallowing. Data were derived from clinical records and instrumental swallow studies, and ranged from demographics, injury characteristics, swallowing biomechanics, medications, and standardized tools (e.g.. Glasgow Coma Scale, Penetration-Aspiration Scale). Bayesian Belief Network modeling was used to analyze the data at intermediate points, guide data collection, and predict outcomes. Predictive models were validated with independent data via receiver operating characteristic curves. Results: The first iteration of the model (n = 48) revealed variables that could be collapsed for the second model (n = 96). The ability to predict recovery from dysphagia improved from the second to third models (area under the curve = 0.68 to 0.86). The third model, based on 161 cases, revealed “initial diet restrictions” as first-degree, and “Glasgow Coma Scale, intubation history, and diet change” as second-degree associates for diet restrictions at discharge. Conclusion: This project demonstrates the potential for bioinformatics to advance understanding of dysphagia. This database in concert with Bayesian Belief Network modeling makes it possible to explore predictive relationships between injuries and swallowing function, individual variability in recovery, and appropriate treatment options

Organ curvature sensing using pneumatically attachable flexible rails in robotic-assisted laparoscopic surgery

In robotic-assisted partial nephrectomy, surgeons remove a part of a kidney often due to the presence of a mass. A drop-in ultrasound probe paired to a surgical robot is deployed to execute multiple swipes over the kidney surface to localise the mass and define the margins of resection. This sub-task is challenging and must be performed by a highly-skilled surgeon. Automating this sub-task may reduce cognitive load for the surgeon and improve patient outcomes. The eventual goal of this work is to autonomously move the ultrasound probe on the surface of the kidney taking advantage of the use of the Pneumatically Attachable Flexible (PAF) rail system, a soft robotic device used for organ scanning and repositioning. First, we integrate a shape-sensing optical fibre into the PAF rail system to evaluate the curvature of target organs in robotic-assisted laparoscopic surgery. Then, we investigate the impact of the PAF rail’s material stiffness on the curvature sensing accuracy, considering that soft targets are present in the surgical field. We found overall curvature sensing accuracy to be between 1.44% and 7.27% over the range of curvatures present in adult kidneys. Finally, we use shape sensing to plan the trajectory of the da Vinci surgical robot paired with a drop-in ultrasound probe and autonomously generate an Ultrasound scan of a kidney phantom

On the methodological unification in electroencephalography

BACKGROUND: This paper presents results of a pursuit of a repeatable and objective methodology of analysis of the electroencephalographic (EEG) time series. METHODS: Adaptive time-frequency approximations of EEG are discussed in the light of the available experimental and theoretical evidence, and applicability in various experimental and clinical setups. RESULTS: Four lemmas and three conjectures support the following conclusion. CONCLUSION: Adaptive time-frequency approximations of signals unify most of the univariate computational approaches to EEG analysis, and offer compatibility with its traditional (visual) analysis, used in clinical applications