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Pencil graphite electrode (PGE) modified with MWCNT and Bi3+ (MWCNT/Bi/PGE) was utilized in simultaneous analysis of Pb2+, Cd2+, and Zn2+. Surface and electrochemical characteristics of MWCNT/Bi/PGE were investigated via SEM, cyclic voltammetry, electrochemical impedance spectroscopy, and FTIR measurements. Even though modification with MWCNT did not improve the electroactive surface area, it significantly decreased the charge transfer resistance. Furthermore, modification with Bi3+ significantly increased the sensitivity. Finally, MWCNT/Bi/PGE exhibited the highest sensitivity and reproducibility compared to PGE and PGE modified with only MWCNT. MWCNT/Bi/PGE provided LOD values of 0.27, 0.43, and 1.63 μg L−1, and linear ranges of 1–80, 5–80, and 10–80 μg L−1 for Pb2+, Cd2+, and Zn2+, respectively. Proposed modification method offers effective electroanalytical performance with low time consumption and cost for the analyst. [ABSTRACT FROM AUTHOR]

Background: YouTube™ is the world's second most popular website after Google on the Internet. The aim of this study was to assess the quality and content of information YouTube™ videos for patients seeking information about teeth whitening. Methods: The keyword 'teeth whitening' was searched on YouTube™. YouTube™ was filtered by the relevance, and the first 100 videos that met the inclusion criteria were evaluated. The included videos were analyzed for views, duration, time since video upload, likes/dislikes, number of comments, source, material types (dental, natural, and other). Also, video purpose was analyzed under nine categories (definition, material preparation, the procedure of application, material comparison, before/after comparison, symptoms, post-op experience, commercial, educational). Each video was classified according to the quality of information content as 'good', 'moderate', or 'poor'. The Kruskal-Wallis test, Fischer's Exact test and Spearman correlation analyses were performed. Results: Most videos were uploaded by laypersons (60.0%). The definition of teeth whitening was the most commonly covered topic (74.0%), followed by the procedure of application (54.0%), and post-op experience (36.0%). Only 12% of videos were classified as having good information quality content, 53% moderate, and 35% were rated as poor information content. Poor-information content videos had a significantly higher number of viewing rates than the other groups (P = 0.002), besides the duration was significantly higher in poor-information content videos (P =0.002). There was a significant relationship between the quality of video information and material types (P <0.001). Conclusions: YouTube™ should not be used as a thoroughly reliable and accurate source for patient information about teeth whitening. More informative and reliable content YouTube™ videos about teeth whitening should be uploaded by professionals. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the content of oral habit videos on YouTube™.Materials and Methods: The four keywords "Oral Habits," "Thumb Sucking," "Tongue Thrust", and "Finger Sucking" relevant terms oral habits were searched on YouTube™. The videos sorted by view count were screened and evaluated. The following exclusion criteria were defined as; non-English videos, unrelated to a topic, poor audio-video quality, and duplication. A hundred videos were analyzed for general video characteristics (number of views, likes, dislikes, number of comments, and uploaded date) the purpose of the video, information content, audio-visual quality, and viewers' interaction index.Results: The top hundred videos have been viewed an average of 26,870.83 times. Most videos were uploaded by dentists (n = 29; 29.0%). Most of the videos (44.0%) were classified as having moderate general information content and 38.0% were rated as good, and 18.0% were rated as poor. Videos generally involved information about oral habits (82.0%), followed by personal experience (12.0%). The viewers' interaction index of all evaluated YouTube™ videos was 0.59. Good content videos had a significantly higher interaction index than the other groups (P = 0.011).Conclusions: YouTube™ videos about the oral habits are generally inadequate and patients must be recommended to view them with caution. High quality and more informative videos about oral habits in dentistry should be uploaded to YouTube™ by professionals. [ABSTRACT FROM AUTHOR]

In current practice, optimal placement of deep-brain stimulators (DBSs) used to treat movement disorders in patients with Parkinson's disease and essential tremor is an iterative procedure. A target is chosen preoperatively based on anatomical landmarks identified on magnetic resonance images. This point is used as an initial position that is refined intraoperatively using both microelectrode recordings and macrostimulation. In this paper, we report on our current progress toward developing a system for the computer-assisted preoperative selection of target points and for the intraoperative adjustment of these points. The system consists of a deformable atlas of optimal target points that can be used to select automatically the preoperative target, of an electro-physiological atlas, and of an intraoperative interface. Results we have obtained show that automatic prediction of target points is an achievable goal. Our results also indicate that electrophysiological information could be used to resolve structures not visible in anatomic images, thus improving both preoperative and intraoperative guidance. Our intraoperative system has reached the stage of a working prototype and we compare targeting accuracy as well as the number of paths needed to reach the targets with our system and with the method in current clinical use. [ABSTRACT FROM AUTHOR]

Objectives: Application of image-guided surgery to otology has been limited by the need for submillimeter accuracy via a fiducial system that is easily usable (noninvasive and nonobstructive). Methods: A dental bite-block was fitted with a rigid frame with 7 fiducial markers surrounding each external ear. The temporal bones of 3 cadaveric skulls were removed and replaced with surgical targets arranged in a bull’s-eye pattern about the centroid of each temporal bone. The surgical targets were identified both within CT scans and in physical space using an infrared optical tracking system. The difference between positions in CT space versus physical space was calculated as target registration error. Results: A total of 234 independent target registration errors were calculated. Mean ± standard deviation = 0.73 mm ± 0.25 mm. Conclusions: These findings show that image-guided otologic surgery with submillimeter accuracy is achievable with a minimally invasive fiducial frame. Significance: In vivo validation of the system is ongoing. With such validation, this system may facilitate clinically applicable image-guided otologic surgery. EBM rating: A. [Copyright &y& Elsevier]

In this study, a new system was evaluated for implanting deep-brain stimulators based on a one-piece platform for each trajectory customized from a preoperative planning image. During surgery, the platform is attached to skull-implanted posts that extend through the scalp. The platform acts as a miniature stereotactic frame to provide guidance for parallel cannulas as they are advanced through a burr hole to the target. Accuracy is determined from a postoperative CT. For each implantation, the distance between the position observed in the postoperative image and the position calculated relative to the platform from the preoperative image is our measure of error. Because this measure incorporates the surgical error of electrode anchoring, brain shift between preoperative and postoperative scanning, and error in the measurement of the position of the electrode in CT, it will tend to overestimate the true error. The mean error was 2.8 mm for 20 implantations. These data reflect favorably the accuracy of this system when compared with others. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: Otologic surgery is undertaken to treat ailments of the ear, including persistent infections, hearing loss, vertigo, and cancer. Typically performed on otherwise-healthy patients in outpatient facilities, the application of image-guided surgery (IGS) has been limited because accurate ( Methods: A dental bite-block was fitted with a custom-designed rigid frame with 7 fiducial markers surrounding each external ear. The bones containing the ear (i.e., the temporal bones) of 3 cadaveric skulls were removed and replaced with discs containing 13 surgical targets arranged in a cross-hair pattern about the centroid of each ear. The surgical targets (26/skull) and fiducial markers (14/skull) were identified both within CT scans using a published algorithm and in physical space using an infrared optical tracking system. Fiducial registration error (FRE), fiducial localization error (FLE), and target registration error (TRE) were calculated. Results: For all trials, root mean square FRE=0.66, FLE=0.72, and TRE=0.77mm. The mean TRE for n=234 independent targets was 0.73 with a standard deviation of 0.25mm. Conclusions: Using a novel, non-invasive fiducial system (the EarMark™), submillimetric accuracy was repeatably achieved. This system will facilitate image-guided otologic surgery. [ABSTRACT FROM AUTHOR]