Exceptional performance is often considered to be elegant and free of ‘errors’ or missteps. During the most extreme escape behaviours, neural control can approach or exceed its operating limits in response time and bandwidth. Here we show that small, rapid running cockroaches with robust exoskeletons select head-on collisions with obstacles to maintain the fastest escape speeds possible to transition up a vertical wall. Instead of avoidance, animals use their passive body shape and compliance to negotiate challenging environments. Cockroaches running at over 1 m or 50 body lengths per second transition from the floor to a vertical wall within 75 ms by using their head like an automobile bumper, mechanically mediating the manoeuvre. Inspired by the animal's behaviour, we demonstrate a passive, high-speed, mechanically mediated vertical transitions with a small, palm-sized legged robot. By creating a collision model for animal and human materials, we suggest a size dependence favouring mechanical mediation below 1 kg that we term the ‘Haldane limit’. Relying on the mechanical control offered by soft exoskeletons represents a paradigm shift for understanding the control of small animals and the next generation of running, climbing and flying robots where the use of the body can off-load the demand for rapid sensing and actuation.

Productivity is improved when the font is increased from 1.78 or 2.23 to 3.56 mm for text-based computer tasks. The largest font size corresponds to a visual angle of font of 23.4 arcmin. This visual angle of font is above the high end of ISO recommendations (International Organization for Standardization, 1992, 2011). The findings may be useful for setting the font sizes for computers and for training office workers.

PurposeTo evaluate a physician's impression of a urinary stone patient's dietary intake and whether it was dependent on the medium through which the nutritional data were obtained. Furthermore, we sought to determine if using an electronic food frequency questionnaire (FFQ) impacted dietary recommendations for these patients.Materials and MethodsSeventy-six patients attended the Stone Clinic over a period of 6 weeks. Seventy-five gave consent for enrollment in our study. Patients completed an office-based interview with a fellowship-trained endourologist, and a FFQ administered on an iPad. The FFQ assessed intake of various dietary components related to stone development, such as oxalate and calcium. The urologists were blinded to the identity of patients' FFQ results. Based on the office-based interview and the FFQ results, the urologists provided separate assessments of the impact of nutrition and hydration on the patient's stone disease (nutrition impact score and hydration impact score, respectively) and treatment recommendations. Multivariate logistic regressions were used to compare pre-FFQ data to post-FFQ data.ResultsHigher FFQ scores for sodium (odds ratio [OR], 1.02; p=0.02) and fluids (OR, 1.03, p=0.04) were associated with a higher nutritional impact score. None of the FFQ parameters impacted hydration impact score. A higher FFQ score for oxalate (OR, 1.07; p=0.02) was associated with the addition of at least one treatment recommendation.ConclusionsInformation derived from a FFQ can yield a significant impact on a physician's assessment of stone risks and decision for management of stone disease.

No abstract

Objectives To evaluate the changes in use of the different imaging modalities for diagnosing upper tract urothelial carcinoma (UTUC) and assess how these changes have affected tumor stage at the time of surgery. Materials and methods We assessed the Surveillance, Epidemiology, and End Results (SEER) cancer registry and linked Medicare claims data (1992–2009) for 5377 patients who underwent surgery for UTUC. We utilized International Classification of Disease—Oncology 3 codes to identify UTUC. International Classification of Disease, ninth Revision, Clinical Modification and Current Procedure Terminology codes identified surgical treatment and imaging modalities. We assessed for use of intravenous pyelography, retrograde pyelography (RGP), computed tomography urography (CTU), magnetic resonance urography (MRU), and endoscopy. For each modality, patients were categorized as having received the modality at least once or not at all. Patient characteristics were compared using chi-squared tests. Usage of imaging modalities and tumor stage was trended using Cochran-Armitage tests. We stratified our data into 2 multivariate logistic regression models to determine the effect of imaging modalities on tumor stage: 1992 to 1999 with all modalities except MRU, and 2000 to 2009 with all modalities. Results Our patient population was predominantly White males of more than 70 years old. Intravenous pyelography and RGP declined in use (62% and 72% in 1992 vs. 6% and 58% in 2009, respectively) while computed tomography urography, MRU, and endoscopy increased in use (2%, 0%, and 37% in 1992 vs. 44%, 6%, and 66% in 2009, respectively). In both regression analyses, endoscopy was associated with lower-stage tumors. In the 2000 to 2009 model, RGP was associated with lower-stage tumors, and MRU was associated with higher-stage tumors. Finally, our data showed an increasing number of modalities utilized for each patient (1% receiving 4 modalities in 1992 vs. 20% in 2009). Conclusions We found trends toward the utilization of newer imaging modalities to diagnose UTUC and more modalities per patient. Endoscopy and RGP were associated with smaller tumors, whereas MRU was associated with larger tumors. Further studies are needed to evaluate the utility of the different modalities in diagnosing UTUC.

The purpose of this study is to determine the effects of pudendal nerve stimulation (PNS) on reflex bladder activity and develop an animal model of underactive bladder (UAB). In six anesthetized cats, a bladder catheter was inserted via the urethra to infuse saline and measure pressure. A cuff electrode was implanted on the pudendal nerve. After determining the threshold intensity (T) for PNS to induce an anal twitch, PNS (5 Hz, 0.2 ms, 2T or 4T) was applied during cystometrograms (CMGs). PNS (4-6T) of 30-min duration was then applied repeatedly until bladder underactivity was produced. Following stimulation control CMGs were performed over 1.5-2 hours to determine the duration of bladder underactivity. When applied during CMGs, PNS (2T and 4T) significantly (p<0.05) increased bladder capacity while PNS at 4T also significantly (p<0.05) reduced bladder contraction amplitude, duration, and area under contraction curve. Repeated application of 30-min PNS for a cumulative period of 3-8 hours produced bladder underactivity exhibiting a significantly (p<0.05) increased bladder capacity (173±14% of control) and a significantly (p<0.05) reduced contraction amplitude (50±7% of control). The bladder underactivity lasted more than 1.5-2 hours after termination of the prolonged PNS. These results provide basic science evidence supporting the proposal that abnormal afferent activity from external urethral/anal sphincter could produce central inhibition that underlies non-obstructive urinary retention (NOUR) in Fowler's syndrome. This cat model of UAB may be useful to investigate the mechanism by which sacral neuromodulation reverses NOUR in Fowler's syndrome.

No abstract

Introduction: Our urology residency program transitioned to a night float system, where dedicated residents cover nights and are off duty during the day. Junior residents previously covered 5 hospitals every 5 to 7 nights and worked the following day (home call). This prospective observational study compared the 2 systems before and after the transition.Methods: A validated survey was administered to residents and faculty to evaluate patient care, communication, quality of life, resident education, and duty hour violations. A separate survey was administered to nurses evaluating the on-call resident. Sleep was measured using actigraphy.Results: Survey response rates were 80% to 100%. Junior residents rated night float as equivalent to home call for surgical case volume and superior in all other respects (p <0.05). Senior residents rated night float as superior for continuity of care, compassion, safety, efficiency for the day team, communication with nurses, quality of life, and time for reading and research (p <0.05). Faculty rated night float as superior for efficiency for the day team, handoffs, quality of life, and time for research (p <0.05). Nurses rated night float higher for availability, knowledge of plan for patient, respectfulness, communication, and ability to identify the resident on call (p <0.05). Mean duration of sleep was 2.5 and 7.1 hours for home call and night float, respectively (p <0.001). Junior residents reported fewer violations of the 80-hour and 8-hour-off rules with night float (p <0.001).Conclusions: Physicians and nurses perceived night float to improve multiple domains. Residents slept more and had fewer duty hour violations on night float.