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Continuum robots navigate narrow, winding passageways while safely and compliantly interacting with their environments. Sensing the robot's shape under these conditions is often done indirectly, using a few coarsely distributed (e.g., strain or position) sensors combined with the robot's mechanics-based model. More recently, given high-fidelity shape data, external interaction loads along the robot have been estimated by solving an inverse problem on the mechanics model of the robot. In this article, we argue that since shape and force are fundamentally coupled, they should be estimated simultaneously using a statistically principled approach. We accomplish this by applying continuous-time batch estimation directly to the arclength domain. A general continuum robot model serves as a statistical prior that is fused with discrete, noisy measurements taken along the robot's backbone. The result is a continuous posterior containing both shape and load functions of arclength, as well as their uncertainties. We first test the approach with a Cosserat rod, i.e., the underlying modeling framework that is the basis for a variety of continuum robots. We verify our approach numerically using distributed loads with various sensor combinations. Next, we experimentally validate shape and external load errors for highly concentrated force distributions (point loads). Finally, we apply the approach to a tendon-actuated continuum robot demonstrating applicability to more complex actuated robots.

A breeze blew his white hair out of its perfectplace a few times, and when he removed his handfrom hers to smooth it down, she stopped andtightened her grip. Headswith hats and caps, heads with blackhair and blond hair, male and female,long and short hair, no hair--theyturned and craned their necks to seebehind them, and whatever they sawcaused them to set aside their greedyquest for line position and move to oneside or the other. The automatic glass door at the airportentrance saw me coming. Her short black hair topped a round, cherub-likeface. [Extracted from the article]

Objective: The objective of this study was to plan for a series of culturally competent and sexually appropriate public health interventions for a highly mobile population of men who have sex with men (MSM). Goal: The goal of this study was to conduct a comprehensive needs assessment. Study: A cross-sectional survey with a multistage probability sample of unmarried adult MSM living in households was conducted. Results: A total of 918 residential units were screened, 154 eligible men were identified, and 140 mostly white (56%) and Hispanic (34%) MSM (median = 33.5 years old) were enrolled (90.9% response rate). Almost half (47%) reported engaging in unprotected anal intercourse in the previous 12 months. Drug use was common. Almost one third (31.0%) tested positive for the HIV antibody. Estimated annual incidence of HIV infection was 10.0%. Conclusions: Population-based HIV antibody testing revealed a remarkably high annual incidence of HIV infection. A community-based organization was transformed to implement a social marketing campaign and provide other disease prevention services for MSM.

Abstract: The ecological perspective is a proven approach for worksite health promotion program design. This paper presents a protocol to look at health behaviors from an ecological perspective that assumes [...]

Selections from a report defending affirmative action practices in colleges and universities are presented. Topics include the benefits of a diverse educational environment, the role of democracy in education, the results of diversity studies, and the consequences of abandoning diversity in higher education.

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Purpose: During traditional insertion of cochlear implant (CI) electrode arrays (EAs), surgeons rely on limited tactile feedback and visualization of the EA entering the cochlea to control the insertion. One insertion approach for precurved EAs involves slightly overinserting the EA and then retracting it slightly to achieve closer hugging of the modiolus. In this work, we investigate whether electrical impedance sensing could be a valuable real-time feedback tool to advise this pullback technique. Methods: Using a to-scale 3D-printed scala tympani model, a robotic insertion tool, and a custom impedance sensing system, we performed experiments to assess the bipolar insertion impedance profiles for a cochlear CI532/632 precurved EA. Four pairs of contacts from the 22 electrode contacts were chosen based on preliminary testing and monitored in real time to halt the robotic insertion once the closest modiolar position had been achieved but prior to when the angular insertion depth (AID) would be reduced. Results: In this setting, the open-loop robotic insertion impedance profiles were very consistent between trials. The exit of each contact from the external stylet of this EA was clearly discernible on the impedance profile. In closed-loop experiments using the pullback technique, the average distance from the electrode contacts to the modiolus was reduced without greatly affecting the AID by using impedance feedback in real time to determine when to stop EA retraction. Conclusion: Impedance sensing, and specifically the access resistance component of impedance, could be a valuable real-time feedback tool in the operating room during CI EA insertion. Future work should more thoroughly analyze the effects of more realistic operating room conditions and inter-patient variability on this technique.

Online marketing has gone through three distinct phases so far, where innovation and economic upheaval have more or less systematically brought about the end of one era and a shift [...]

A variety of robot-assisted surgical systems have been proposed to improve precision in the most challenging eye surgeries. However, little attention has been paid to patient motion due to breathing, snoring, talking, and other events that are common during eye surgery. This is problematic because patient motion is typically relative to a grounded surgical robot. In this paper, we characterize the benefits of a new paradigm in which robots are mounted semirigidly and noninvasively to the patient’s head. This paradigm utilizes compact high-precision telerobotic systems that have been designed for this use. We present an initial design concept focused on eye surgery, and demonstrate an order-of-magnitude improvement of within-breathing-cycle motion relative to the robot compared to a pillow rest, with an optional head strap, which is the current standard of care, while essentially eliminating gross relative motion. We conduct a human-subjects study to quantify the relative motion that remains. Finally, we present an alternative design concept that leaves the patient’s face unobstructed, which may be of interest for other kinds of surgery as well.

Ever walk around your motorhome and accidentally bang your head on the corner of one of the slideouts? Me too. To save your head, slice a foam swim noodle on [...]

Purpose: Insertion trajectory affects final intracochlear cochlear implant (CI) positioning, but limited information is available intraoperatively regarding ideal trajectory. We sought to improve intracochlear positioning CI electrodes using custom templates to specify insertion trajectory. Methods: 3D reconstructions were created from computed tomography of three cadaveric temporal bones. Trajectories co-planar with the straight segment of the cochlea’s basal turn were considered ideal. Templates were designed to fit against the drilled mastoid’s surface and convey this guided trajectory via a hollow cylinder. Templates were 3D-printed using stereolithography. Mastoidectomy was performed. Template accuracy was tested by measuring target registration error (TRE) for four templates. A novel, roller-based insertion tool (designed to fit within the template cylinder) constrained insertions to intended trajectories. Insertions were performed with MED-EL Standard electrodes in three bones with three conditions: guided trajectory with insertion tool, non-guided trajectory with insertion tool and guided trajectory with surgical forceps. For the final condition, the template was used to mark the mastoid to convey trajectory. Insertion was stopped when electrode buckling occurred. Results: TRE ranged from 0.23 to 0.73 mm. Mean TRE ± standard deviation was 0.55 ± 0.19 mm. Insertions along guided versus non-guided trajectories averaged more intracochlear electrodes (9, 8, 8 vs. 7, 7, 8) and greater angular insertion depths (AID) (377°, 341°, 320° vs. 278°, 302°, 290°). Insertions performed with forceps using templates as a guide also achieved excellent results (intracochlear electrodes: 10, 7, 8; AID: 478°, 318°, 333°). No translocations occurred. Conclusion: Custom mastoid-fitting templates reliably specify intended insertion trajectory and provide sufficient information for recreation of that trajectory with manual insertion after template removal. The templates can accurately target structures within the temporal bone with a TRE of 0.55 ± 0.19 mm. Our roller-based insertion tool achieves results comparable to manual insertion using surgical forceps.

Presents letters to the editor of "Time" magazine regarding articles found in previous issues of the journal. Responses to a cover article on Pope John Paul II, found in the April 11, 2005, issue; Discussion of the inequality between Catholic women and men; Response to the article "No Holds Barred," regarding a summary of the presidential commission's intelligence report in the false conclusion that Iraqi leader Saddam Hussein had weapons of mass destruction; Discussion of the article "A New Idea For Democrats: Democracy," by Joe Klein, regarding the right of the Senate minority to filibuster; Reference to the book "My Life So Far," by Jane Fonda; Others.