Intraoperative Management of Tracheal Cautery Injury in a Post-Bypass Cardiac Surgery Patient.

We present the case of a tracheal injury that occurred during a Maze procedure performed via sternotomy that was not initially detected by ventilator air leak, but rather by the visual presence of gas bubbles escaping the trachea during chest irrigation. Careful investigation and machine check did reveal a subsequent air leak that would have otherwise been overlooked. Furthermore, the use of intraoperative bronchoscopy was essential in guiding and confirming surgical repair. This case underscores the need for ongoing vigilance and suggests the utility of chest irrigation with Valsalva maneuvers after procedures performed in the vicinity of the trachea to exclude injury.

Subspace wavefront estimation using image sharpening and predictive dynamic digital holography.

Image sharpening algorithms used for phase retrieval to reconstruct images in digital holography are computationally intensive, requiring iterative virtual wavefront propagation and hill-climbing algorithms to optimize sharpness criteria. Recently, it was shown that minimum-variance wavefront prediction can be integrated with digital holography and image sharpening to significantly reduce the large number of costly sharpening iterations normally required to achieve near-optimal wavefront estimation [J. Opt. Soc. Am. A35, 923 (2018)JOAOD60740-323210.1364/JOSAA.35.000923]. This paper demonstrates further gains in computational efficiency with a new subspace sharpening method in conjunction with predictive dynamic digital holography for real-time applications. The method sharpens local regions of interest in an image plane by parallel independent wavefront estimation on reduced-dimension subspaces of the complex field in a pupil plane. Through wave-optics simulations, this paper shows that the new subspace method produces results comparable to those of conventional global and local sharpening, and that subspace wavefront estimation and sharpening coupled with wavefront prediction achieve orders-of-magnitude increases in processing speed.

Predictive dynamic digital holography and image sharpening.

Digital holography is often combined with image sharpening for wavefront estimation and correction, and this combination has received recent attention for many imaging and sensing applications. A significant obstacle for digital holography and image sharpening in high-speed real-time applications is the fact that the process is computationally intensive, requiring iterative virtual wavefront propagation and hill-climbing algorithms to optimize sharpness criteria. This paper introduces a method for accelerating dynamic digital holography and image sharpening by wavefront prediction. The approach here integrates optimal state-space prediction filters with digital holography and image sharpening to short-circuit the computationally intensive process of virtual wavefront propagation and sharpness optimization.

Rates and Correlates of Syphilis Reinfection in Men Who Have Sex with Men.

PURPOSE: This study examined rates and correlates of syphilis reinfection in men who have sex with men (MSM). METHODS: From 2012 to 2015, time to reinfection was assessed in 323 MSM receiving initial treatment for syphilis in San Francisco. RESULTS: One in five men was reinfected (71/323; 22%). The rate of syphilis reinfection was greater among HIV-infected men (adjusted hazard ratio [aHR] = 1.96; 95% confidence interval [95% CI] = 1.16-3.31) and ketamine users (aHR = 2.76; 95% CI = 1.09-7.00). CONCLUSION: Expanded prevention efforts are needed with HIV-infected and substance-using MSM to reduce the burden of reinfection in this population.

Collimated focal ratio degradation testing for highly multiplexed fiber systems-an improvement to a standard test.

A simple method for determining the focal ratio degradation of optical fibers has been developed. The method involves splitting the light from the test fiber and recording ring patterns that have traveled over two different, and known, optical paths. This new method will be valuable for testing many fibers as will be needed for new multiobject astronomical spectrographs.

On-sky demonstration of optimal control for adaptive optics at Palomar Observatory.

High-order adaptive optics systems often suffer from significant computational latency, which ultimately limits the temporal error rejection bandwidth when classical controllers are employed. This Letter presents results from an on-sky, real-time implementation of an optimal controller on the PALM-3000 adaptive optics system at Palomar Observatory. The optimal controller is computed directly from open-loop wavefront measurements using a multichannel subspace system identification algorithm, and mitigates latency by explicitly predicting incident turbulence. Experimental results show a significant reduction in the residual wavefront error over the controlled spatial modes, illustrating the superior performance of the optimal control approach versus the nominal integral control architecture.

Optimal and adaptive control of aero-optical wavefronts for adaptive optics.

This paper compares two control methods to predict and correct aero-optical wavefronts derived from recent flight-test data. The first is an optimal linear time-invariant controller constructed from an identified state-space model of the turbulence flow. The second control method is an adaptive controller based on a recursive least-squares lattice filter. The performance of these control schemes versus classical integrator methods is investigated in an adaptive optics experiment that reproduces the aberrations from in-flight measurements of aero-optical turbulence. Experimental results show the improvement in wavefront correction achieved by both prediction methods. Altering the flow characteristics of the disturbance wavefront during the control process illustrates the ability of the adaptive controller to track changes in the aberration statistics.

A nurse practitioner residency pilot program: a journey of learning.

A collaborative team developed a year long residency experience for a staff nurse transitioning to a nurse practitioner role in the Veterans Affairs system. To assist others desiring to provide support, networking, and infrastructure to those transitioning into new roles, the authors discuss strengths and weaknesses of the pilot and lessons learned related to defining trainee versus resident, credentialing and privileging, and specific mentoring needed for the role of the nurse practitioner.

Adaptive control in an adaptive optics experiment.

This paper presents results from an adaptive optics experiment in which an adaptive control loop augments a classical adaptive optics feedback loop. Closed-loop wavefront errors measured by a self-referencing interferometer are fed back to the control loops, which drive a membrane deformable mirror to correct the wavefront. The paper introduces new frequency-weighted deformable mirror modes used as the control channels and new wavefront sensor modes for analyzing the performance of the control loops. The corrected laser beam also is imaged by a diagnostic target camera. The experimental results show reduced closed-loop wavefront errors and correspondingly sharper diagnostic target images produced by the adaptive control loop as compared with the classical AO loop.

GPs' attitudes to benzodiazepine and 'Z-drug' prescribing: a barrier to implementation of evidence and guidance on hypnotics.

Zaleplon, zolpidem, and zopiclone ('Z-drugs') prescribing is gradually rising in the UK, while that of benzodiazepine hypnotics is falling. This situation is contrary to current evidence and guidance on hypnotic prescribing. The aim of this study was to determine and compare primary care physicians' perceptions of benefits and risks of benzodiazepine and Z-drug use, and physicians' prescribing behaviour in relation to hypnotics using a cross-sectional survey. In 2005 a self-administered postal questionnaire was sent to all GPs in West Lincolnshire Primary Care Trust. The questionnaire investigated perceptions of benefits and disadvantages of benzodiazepines and Z-drugs. Of the 107 questionnaires sent to GPs, 84 (78.5%) analysable responses were received. Responders believed that Z-drugs were more effective than benzodiazepines in terms of patients feeling rested on waking (P<0.001), daytime functioning (P<0.001), and total sleep time (P = 0.03). Z-drugs were also thought to be safer in terms of tolerance (P<0.001), addiction (P<0.001), dependence (P<0.001), daytime sleepiness (P<0.001), and road traffic accidents (P = 0.018), and were thought to be safer for older people (P<0.001). There were significant differences between GPs' perceptions of the relative benefits and risk of Z-drugs compared with benzodiazepines. The majority of practitioners attributed greater efficacy and lower side effects to Z-drugs. GPs' beliefs about effectiveness and safety are not determined by current evidence or national (NICE) guidance which may explain the increase in Z-drug prescribing relative to benzodiazepine prescribing.