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In an era of emerging vehicle automation technologies and advanced traffic management strategies, traffic simulation has become an indispensable tool for giving agencies the insight they need for adoption and implementation decisions. The importance of calibration to ensure reliability of the simulation results cannot be over-stated. Current practice calls for analysts to calibrate their analytical tools to a base (or existing) condition, and then use those tools to predict performance of a future condition. However, many times these future conditions incorporate improvements that are significantly different than the base condition modeled when the analysis tool was calibrated. This can result in performance outcomes that are either not trustworthy, or just plain wrong. New approaches must be developed, so that the tools are calibrated to data that are reflective of what the future condition will be. With implications of future conditions in mind, this study proposes a framework for calibration of simulation models. The framework is built around the following four major components: scenarios, robustness, parameter libraries, and simulation agent trajectories. The role of the framework components is shown in a case study. Guidelines based on the proposed framework could be incorporated in conjunction with existing software packages. However, future development of intermediate tools is recommended, for improved efficiency and practicality. The ultimate result of utilizing the framework will be more accurate and better qualified traffic analyses, leading to improved trust in analysis tools, and improved transportation decision-making overall.

The Zwicky Transient Facility (ZTF) has been observing the entire northern sky since the start of 2018 down to a magnitude of 20.5 (5σ for 30 s exposure) in the g, r, and i filters. Over the course of two years, ZTF has obtained light curves of more than a billion sources, each with 50–1000 epochs per light curve in g and r, and fewer in i. To be able to use the information contained in the light curves of variable sources for new scientific discoveries, an efficient and flexible framework is needed to classify them. In this paper, we introduce the methods and infrastructure that will be used to classify all ZTF light curves. Our approach aims to be flexible and modular and allows the use of a dynamical classification scheme and labels, continuously evolving training sets, and the use of different machine-learning classifier types and architectures. With this setup, we are able to continuously update and improve the classification of ZTF light curves as new data become available, training samples are updated, and new classes need to be incorporated.

The Zwicky Transient Facility (ZTF) Observing System (OS) is the data collector for the ZTF project to study astrophysical phenomena in the time domain. ZTF OS is based upon the 48-inch aperture Schmidt-type design Samuel Oschin Telescope at the Palomar Observatory in Southern California. It incorporates new telescope aspheric corrector optics, dome and telescope drives, a large-format exposure shutter, a flat-field illumination system, a robotic bandpass filter exchanger, and the key element: a new 47-square-degree, 600 megapixel cryogenic CCD mosaic science camera, along with supporting equipment. The OS collects and delivers digitized survey data to the ZTF Data System (DS). Here, we describe the ZTF OS design, optical implementation, delivered image quality, detector performance, and robotic survey efficiency., 31 pages, 26 figures, 5 tables; published in the Publications of the Astronomical Society of the Pacific

A debate in the marriage and family therapy profession that continues is whether a therapy approach is effective if it doesn't have scientific empirical data to back up its effectiveness or, stated another way, is it evidence-based? A practice-based approach, specifically, the MRI (Mental Research Institute) Brief Therapy approach, has stood the test of time, although its research base may not have used currently popular research protocols. Outcome studies have shown its effectiveness, and today, it is practiced worldwide. While new approaches in therapeutic practice have developed over time, the practice of the MRI Brief Therapy approach continues to demonstrate usefulness across the widest range of presenting problems. A case example is presented as an illustration of utilizing the MRI Brief Therapy approach in couples therapy, which represents the efficacy of the approach that has a history dating back to the early 1950s, and has proven staying power, unwavering evidence of its effectiveness.

The Highway Capacity Manual 2010 (HCM 2010) contains computational procedures for evaluating traffic operational efficiency of urban street segments. These procedures have been implemented within several commercial software packages and are likely used by thousands of engineers and planners across the United States. The procedures for urban street capacity analysis contain no logic for handling right turns on red (RTORs) or for handling special cases of RTORs such as shielded and free right turns. A new proposed RTOR modeling framework is described for urban streets in the HCM 2010. When significant upstream RTOR flows exist, the proposed logic is designed to generate more realistic flow profiles. Three types of experimental results are presented: they demonstrate the improved modeling accuracy of the proposed logic. First, it is shown that macroscopic flow profile shapes are now more visually sensible because they now illustrate RTOR flows moving at the appropriate times. Second, macroscopic flow profile shapes are now more consistent with microscopic vehicle trajectories. Third, a statistical analysis shows that when the proposed logic is used, HCM 2010 performance measures become more consistent with the performance measures generated by microsimulation. Finally, case study results show that when the proposed RTOR logic is not used, control delays are sometimes be inaccurate by more than 30%. Given the experimental evidence presented, it is urgent that the proposed improvements be adopted and implemented so that RTOR corridors can be accurately analyzed by the HCM 2010 procedures.

Hard shoulder running (HSR), used in many large cities for reducing peak hour recurring congestion, has been proved effective. This paper looks at another perspective of using hard shoulders and proposes dynamic hard shoulder running (D-HSR) for traffic incident management. The purpose of this paper is to show the benefits and make recommendations to state departments of transportation and local agencies on how to use hard shoulders dynamically to reduce the effects of nonrecurring traffic incidents. An approach based on microscopic simulation with factorial experimental design is adopted in this study, and interesting results are obtained from the discussion and statistical analyses of simulation results: ( a) D-HSR strategies are more suitable for property damage only incidents in which traffic operations centers have more flexibility in managing traffic; ( b) only the part of the shoulder that is 0.5 mi upstream and downstream of the incident location needs to be opened to achieve maximum benefits for relieving a bottleneck; ( c) the opened shoulder can be closed after the incident is cleared, and opening the shoulder for a longer time will not improve traffic conditions; and ( d) the effectiveness of D-HSR is significant across different roadway geometry, traffic, and incident scenarios. Equations to estimate potential benefits are also available in this paper. These results are favorable particularly in practice because shoulders need to serve as refuge areas for incident vehicles and be used by emergency vehicles. It is recommended that departments of transportation and local agencies consider D-HSR for relieving congestion during incidents.

The transient universe is fast becoming one of the most important research areas in astronomy. Finding objects that change, either quickly or periodically, has opened up new understanding of the cosmos around us, and brought up new questions that require further investigation. The Zwicky Transient Facility (ZTF) has been developed to observe as much of the sky as possible at a rapid rate, in order to expand the regime of time domain measurement to shorter intervals and detect changes in the sky more quickly. ZTF is a fully automated system, composed of the Samuel Oschin 48-inch (1.2m) telescope at Palomar Observatory (P48), the mosaic camera constructed by Caltech, a filter exchange system, associated sensors and electrical systems, and the Robotic Observing Software (ROS) that controls the operation of the entire system. P48 is a 70 year old telescope that has been upgraded with new hardware, electronics, and a modern telescope control system to allow it to move quickly and accurately across the sky under robotic control. The ZTF mosaic camera is a custom system composed of 16 6Kx6K pixel CCDs, creating a mosaic camera with over 576 million pixels that can image 47 square degrees down to a magnitude of 20.5 in a 30 second exposure. The filter exchange system uses a Kuka robotic arm to grab the 400x450mm filters out of a storage closet and place them onto the front of the mosaic camera, where they are held in place by electromagnets and locking pins. A full sensor system monitors the health of the camera dewar and environment of the observatory; a separate weather station monitors the outside environment. Other subsystems control the motion of the Hexapod that the mosaic camera is mounted on, the top end shutter, and remote switching of power, Managing all of these subsystems is ROS, which is the automated control software that runs ZTF observations. ROS is based on the Robo-AO control system, with improved automation procedures and expanded capabilities to handle the operations required for ZTF. ROS consists of 31 separate software daemons spread across 5 computer systems (4 to control the mosaic camera, 1 for robotic operation); the robotic control daemon is able to manage all daemons, as well as start and stop their operation as necessary. Watchdog daemons intervene in case of robotic system problems, and each daemon has an internal watchdog that can fix or kill the daemon in case of difficulties; if a daemon dies the robotic system automatically restarts it. ROS controls the start of observations and morning shut down, handles weather monitoring and safely stopping in case of bad weather, and responds to problems in the observing sequence by fixing them or stopping operations and sending a message for help. All calibration measurements are done automatically at the beginning of the night; if the calibrations are interrupted they are completed after observations finish in the morning. A queue system determines the observation priority and revises the order of observations dynamically to optimize observational efficiency. ROS is able to operate with less than 15 second overhead between each standard ZTF observation (with a 7.5 degree slew); this is achieved by reading out thee mosaic camera during telescope slew, then transferring and writing FITS data files during the next exposure. FITS headers are kept synchronized through daemons that gather all relevant FITS header information and distribute that to the camera computers. ROS is able to produce more than 80 mosaic science images per hour in standard survey mode; each mosaic is a total of 380MB compressed, so the system produces more than 30GB of data on disk per hour that have to be transferred off the mountain. A new data transfer system synchronizes the compressed FITS data files to the data analysis servers in Pasadena, CA in parallel with the observing system; images are in place for the data analysis pipelines in less than a minute after the ZTF shutter closes. This presentation will discuss the development and execution of the ZTF observing software, as well as analyze the observational behavior and efficiency of the system during the first few months of on-sky science observations.

Zwicky Transient Facility is an integrated, multi-band astronomical survey system optimized for sensitivity, observing cadence, and efficiency. The key subsystem consists of a 600 megapixel CCD focal plane mounted in a flat-fielding vacuum cryostat, located at the prime focus of the 1.2-meter Samuel Oschin Telescope at Palomar Observatory. Supporting subsystems include a new 2.4-meter optical shutter assembly, a 1.35-meter diameter aspheric corrector plate, a cryostat stabilizing hexapod, a commercial robotic arm-based exchanger, three 440 millimeter width filters, four guide/focus CCDs, and dedicated optics compensating individual field curvature over each of sixteen 6k x 6k science CCDs.To optimize ZTF efficiency, all telescope and dome drives were upgraded for higher speed and acceleration, fast readout electronics were implemented, and a sophisticated robotic control system has been implemented. We present for the first time on-sky results from the recently completed ZTF including its realized optical image quality, CCD noise, and observing efficiency performance and discuss engineering challenges that have been overcome. Early scientific results from the ZTF survey are also included.

WIRC+Pol is a newly commissioned low-resolution (R 100), near-infrared (J and H bands) spectropolarimetry mode of the Wide-field InfraRed Camera (WIRC) on the 200-inch Hale Telescope at Palomar Observatory. The instrument utilizes a novel polarimeter design based on a quarter-wave plate and a polarization grating (PG), which provides full linear polarization measurements (Stokes I, Q, and U ) in one exposure with no need for a polarimetric modulator. The PG also has high transmission across the J and H bands. The instrument is situated at the prime focus of an equatorially mounted telescope. As a result, the system only has one reflection in the light path and the instrument does not rotate with respect to the sky, which provides minimal and stable telescope induced polarization. A data reduction pipeline has been developed for WIRC+Pol to produce linear polarization measurements from observations, allowing, e.g., real-time monitoring of the signal-to-noise ratio of ongoing observations. WIRC+Pol has been on-sky since February 2017. Results from the first year commissioning data show that the instrument has a high dispersion efficiency as expected from the polarization grating. We discuss instrumental systematics we have uncovered in the data, their potential causes, along with calibrations that are necessary to eliminate them. We demonstrate the polarimetric stability of the instrument with RMS variation at 0.2% level over 30 minutes for a bright standard star (J = 8.7). While the spectral extraction is photon noise limited, polarization calibration between sources remain limited by systematics.

Simulation-based optimization of traffic signal timing has become pervasive and popular, in the field of traffic engineering. When the underlying simulation model is well-trusted and/or well-calibrated, it is only natural that typical engineers would want their signal timing optimized using the judgment of that same model. As such, it becomes important that the heuristic search methods typically used by these optimizations are capable of locating global optimum solutions, for a wide range of signal systems. However off-line and real-time solutions alike offer just a subset of the available search methods. The result is that many optimizations are likely converging prematurely on mediocre solutions. In response, this paper compares several search methods from the literature, in terms of both optimality (i.e., solution quality) and computer run times. Simulated annealing and genetic algorithm methods were equally effective in achieving near-global optimum solutions. Two selection methods (roulette wheel and tournament), commonly used within genetic algorithms, exhibited similar effectiveness. Tabu searching did not provide significant benefits. Trajectories of optimality versus run time (OVERT) were similar for each method, except some methods aborted early along the same trajectory. Hill-climbing searches always aborted early, even with a large number of step-sizes. Other methods only aborted early when applied with ineffective parameter settings (e.g. mutation rate, annealing schedule). These findings imply (1) today’s products encourage a sub-optimal “one size fits all” approach, (2) heuristic search methods and parameters should be carefully selected based on the system being optimized, (3) weaker searches abort early along the OVERT curve, and (4) improper choice of methods and/or parameters can reduce optimization benefits by 22–33%.

Dynamic merge control (DMC) can be used in freeway merge areas to change lane allocation dynamically at interchanges. DMC generally prioritizes the facility having higher volume and closes a lane on the lesser-volume roadway. DMC has been implemented in the Netherlands and Germany, where it was reported that the application of DMC significantly improved traffic operations. However the DMC strategy has rarely been studied and has not been implemented in the United States. This research used microsimulation studies with VISSIM to investigate the efficiency of the DMC strategy. Optimum traffic demand thresholds were sought specifically for the geometric case in which a two-lane freeway merged with a three-lane freeway and tapered into four lanes. Major-road traffic demands between 2,500 and 4,600 vehicles per hour were compared against minor-road demands between 3,000 and 4,600 vehicles per hour. The DMC strategy was applied by closing the right lane of the major road, ahead of the merging gore area. The results indicate that (a) the DMC strategy is beneficial for all the previously mentioned traffic demand combinations in regard to average vehicle delay and average vehicle speed; (b) when traffic demand on the minor road exceeds 1,900 vehicles per hour per lane, these benefits become statistically and practically significant; and (c) DMC can greatly alleviate the capacity reductions caused by lane changing in the merge area.

Adaptive traffic-signal control (ATSC) is a traffic management strategy in which traffic-signal timings change, or adapt, based on observed traffic demand. Although ATSC can improve mobility, it also has the potential to reduce crashes because mainline stops should be reduced. This paper aims to evaluate the safety effectiveness of ATSC using the empirical Bayes method. This analysis examines 47 urban or suburban intersections where ATSC was deployed in Virginia using 235 site-years of before data and 66 site-years of after data. Installing ATSC was found to produce a crash modification factor (CMF) for total intersection crashes of 0.83 with a standard error of 0.05. This CMF was statistically significant at a 95 percent confidence level. Fatal and injury crashes did not change by a statistically significant amount, indicating that the primary safety benefit of ATSC was reduction in property damage crashes. Analyses of ATSC safety effects by crash type, by traffic volume level, and by operational...

WIRC+Pol is a newly commissioned low-resolution (R~100), near-infrared (J and H band) spectropolarimetry mode of the Wide-field InfraRed Camera (WIRC) on the 200-inch Hale Telescope at Palomar Observatory. The instrument utilizes a novel polarimeter design based on a quarter-wave plate and a polarization grating (PG), which provides full linear polarization measurements (Stokes I, Q, and U) in one exposure. The PG also has high transmission across the J and H bands. The instrument is situated at the prime focus of an equatorially mounted telescope. As a result, the system only has one reflection in the light path, providing minimal telescope induced polarization. A data reduction pipeline has been developed for WIRC+Pol to produce linear polarization measurements from observations. WIRC+Pol has been on-sky since February 2017. Results from the first year commissioning data show that the instrument has a high dispersion efficiency as expected from the polarization grating. We demonstrate the polarimetric stability of the instrument with RMS variation at 0.2% level over 30 minutes for a bright standard star (J = 8.7). While the spectral extraction is photon noise limited, polarization calibration between sources remain limited by systematics, likely related to gravity dependent pointing effects. We discuss instrumental systematics we have uncovered in the data, their potential causes, along with calibrations that are necessary to eliminate them. We describe a modulator upgrade that will eliminate the slowly varying systematics and provide polarimetric accuracy better than 0.1%., Published in PASP

Microscopic simulation is critical for evaluating the operation strategies of managed lanes. However, most existing tools are limited in their ability to simulate dynamic tolling strategies of managed lanes, particularly those with multiple segments. Three sets of modeling components are developed in this paper to demonstrate simulation of high-occupancy toll (HOT) lane operations. The first component implements three pricing strategies: responsive pricing; a closed-loop, control-based algorithm; and time-of-day pricing. The second component mimics drivers’ lane choice behaviors in the presence of tolls, and the third represents different toll structures for multisegment HOT lane facilities. An enhanced version of CORSIM, which contains these new modeling components, is validated by simulation experiments involving the 95 Express network in South Florida.

The Zwicky Transient Facility Camera (ZTFC) is a key element of the ZTF Observing System, the integrated system of optoelectromechanical instrumentation tasked to acquire the wide-field, high-cadence time-domain astronomical data at the heart of the Zwicky Transient Facility. The ZTFC consists of a compact cryostat with large vacuum window protecting a mosaic of 16 large, wafer-scale science CCDs and 4 smaller guide/focus CCDs, a sophisticated vacuum interface board which carries data as electrical signals out of the cryostat, an electromechanical window frame for securing externally inserted optical filter selections, and associated cryo-thermal/vacuum system support elements. The ZTFC provides an instantaneous 47 deg^2 field of view, limited by primary mirror vignetting in its Schmidt telescope prime focus configuration. We report here on the design and performance of the ZTF CCD camera cryostat and report results from extensive Joule-Thompson cryocooler tests that may be of broad interest to the instrumentation community.

Use of traffic simulation has increased in recent decades; and this high-fidelity modelling, along with moving vehicle animation, has allowed transportation decisions to be made with better confidence. During this time, traffic engineers have been encouraged to embrace the process of calibration, in which steps are taken to reconcile simulated and field-observed performance. According to international surveys, experts, and conventional wisdom, existing (non-automated) methods of calibration have been difficult or inadequate. There has been extensive research on improved calibration methods, but many of these efforts have not produced the flexibility and practicality required by real-world engineers. With this in mind, a patent-pending (US 61/859,819) architecture for software-assisted calibration was developed to maximize practicality, flexibility, and ease-of-use. This architecture is called SASCO (i.e. Sensitivity Analysis, Self-Calibration, and Optimization). The original optimization method within SASCO was based on "directed brute force" (DBF) searching; performing exhaustive evaluation of alternatives in a discrete, user-defined search space. Simultaneous Perturbation Stochastic Approximation (SPSA) has also gained favor as an efficient method for optimizing computationally expensive, "black-box" traffic simulations, and was also implemented within SASCO. This paper uses synthetic and real-world case studies to assess the qualities of DBF and SPSA, so they can be applied in the right situations. SPSA was found to be the fastest method, which is important when calibrating numerous inputs, but DBF was more reliable. Additionally DBF was better than SPSA for sensitivity analysis, and for calibrating complex inputs. Regardless of which optimization method is selected, the SASCO architecture appears to offer a new and practice-ready level of calibration efficiency. (C) 2015 Elsevier Ltd. All rights reserved.

Background We previously reported decreased mortality following implementation of a community-acquired pneumonia guideline derived from specialty society recommendations. However, patients with respiratory failure and sepsis from pneumonia were not included, adjustment for comorbidities was limited, and no guideline compliance data were available. We also questioned whether decreased mortality continued after 1997. Methods We utilized Utah data from the Centers for Medicare and Medicaid from 1993 to 2003 to determine if pneumonia guideline implementation was associated with 30-day all-cause mortality, length of hospital stay, and readmission rate. We adjusted outcomes by age, gender, Deyo comorbidity score, prior hospitalizations, and race. Guideline compliance was measured by initial default guideline antibiotic administration. We included patients ≥ 66 years old with primary International Classification of Diseases, Ninth Revision, Clinical Modification codes 480.0–483.9, 485.0–486.9, 487.0, 507.0 or 518.81, and 038.x with secondary code pneumonia. We excluded patients with prior hospitalization within 10 days, patients with HIV infection or transplant recipients, and patients not treated by physicians closely affiliated with study hospitals. Results Mean (± SD) age of 17,728 pneumonia patients admitted to the hospital was 72.3 ± 12.0 years, 55.2% were female, and 96.0% were white. Within Intermountain Healthcare hospitals, a 1-SD increase (10%) in guideline compliance (range, 61 to 100%) was associated with mortality odds ratio (OR) of 0.92 (95% confidence interval[CI], 0.87 to 0.98; p = 0.007). Mortality OR at 16 Intermountain Healthcare hospitals was 0.89 (95% CI, 0.82 to 0.97; p = 0.007) compared with 19 other Utah hospitals. This mortality difference corresponds to approximately 20 lives saved yearly. The readmission rate was also lower. Conclusion Improved clinical outcomes were associated with pneumonia guideline utilization.

The size and variability of the continuum photosphere of o Ceti have been measured with 11 μm heterodyne interferometry to an accuracy of about 1%. Narrow bandwidths (~0.17 cm-1) were used to avoid spectral lines and measure continuum only. The resulting 11 μm diameter of o Cet is larger than the previously measured visible and near-infrared sizes. In addition, variations in the diameter with phase and a possible elongation have been observed. Visibilities were also measured at wavelengths known to contain strong H2O spectral contamination, giving larger apparent stellar sizes and information on the distribution of hot H2O gas.

Traffic congestion in U.S. cities has grown rapidly in recent years, and numerous solutions are needed to address the problem. New research is described for producing basic improvements in the practice of traffic signal timing design, which is one of the many available weapons for fighting congestion and delay. Models in the literature for predicting traffic-actuated phase times are oversimplified. In some cases, they do not recognize the signal settings associated with today’s controllers, which affect phase times. In other cases, models from the literature do not recognize operational effects (for example, progression, queue blockage, permitted left turn, critical movement, early return to green, and stochastic effects) that affect phase times or that are applicable only to isolated signals instead of coordinated signals. Consequently, the recommended average phase times are not practical, and the resulting performance estimates and timing plan designs are unlikely to materialize in the field. The overall goal of this research is to describe and demonstrate an improved methodology for predicting actuated phase times. An improved methodology is needed to improve the overall timing plan design process. Experimental results indicate an improvement in the accuracy of actuated phase time calculation based on the improved methodology.

Bad pixels are generally treated as a loss of useable area and then excluded from averaged performance metrics. The definition and detection of “bad pixels” or “cosmetic defects” are seldom discussed, perhaps because they are considered self-evident or of minor consequence for any scientific grade detector, however the ramifications can be more serious than generally appreciated. While the definition of pixel performance is generally understood, the classification of pixels as useable is highly application-specific, as are the consequences of ignoring or interpolating over such pixels. CMOS sensors (including NIR detectors) exhibit less compact distributions of pixel properties than CCDs. The extended tails in these distributions result in a steeper increase in bad pixel counts as performance thresholds are tightened which comes as a surprise to many users. To illustrate how some applications are much more sensitive to bad pixels than others, we present a bad pixel mapping exercise for the Teledyne H2RG used as the NIR tip-tilt sensor in the Keck-1 Adaptive Optics system. We use this example to illustrate the wide range of metrics by which a pixel might be judged inadequate. These include pixel bump bond connectivity, vignetting, addressing faults in the mux, severe sensitivity deficiency of some pixels, non linearity, poor signal linearity, low full well, poor mean-variance linearity, excessive noise and high dark current. Some pixels appear bad by multiple metrics. We also discuss the importance of distinguishing true performance outliers from measurement errors. We note how the complexity of these issues has ramifications for sensor procurement and acceptance testing strategies.

We report on the status of PALM-3000, the second generation adaptive optics instrument for the 5.1 meter Hale telescope at Palomar Observatory. PALM-3000 was released as a facility class instrument in October 2011, and has since been used on the Hale telescope a total of over 250 nights. In the past year, the PALM-3000 team introduced several instrument upgrades, including the release of the 32x32 pupil sampling mode which allows for correction on fainter guide stars, the upgrade of wavefront sensor relay optics, the diagnosis and repair of hardware problems, and the release of software improvements. We describe the performance of the PALM-3000 instrument as a result of these upgrades, and provide on-sky results. In the 32x32 pupil sampling mode (15.8 cm per subaperture), we have achieved K-band strehl ratios as high as 11% on a 14.4 mv star, and in the 64x64 pupil sampling mode (8.1 cm per subaperture), we have achieved K-band strehl ratios as high as 86% on stars brighter than 7th m_v.

The sky coverage and performance of laser guide star (LGS) adaptive optics (AO) systems is limited by the natural guide star (NGS) used for low order correction. This limitation can be dramatically reduced by measuring the tip and tilt of the NGS in the near-infrared where the NGS is partially corrected by the LGS AO system and where stars are generally several magnitudes brighter than at visible wavelengths. We present the design of a near-infrared tip-tilt sensor that has recently been integrated with the Keck I telescope’s LGS AO system along with some initial on-sky results. The implementation involved modifications to the AO bench, real-time control system, and higher level controls and operations software that will also be discussed. The tip-tilt sensor is a H2RG-based near-infrared camera with 0.05 arc second pixels. Low noise at high sample rates is achieved by only reading a small region of interest, from 2×2 to 16×16 pixels, centered on an NGS anywhere in the 100 arc second diameter field. The sensor operates at either Ks or H-band using light reflected by a choice of dichroic beamsplitters located in front of the OSIRIS integral field spectrograph.

A detailed description is given of the Infrared Spatial Interferometer (ISI), developed at the Space Sciences Laboratory of the University of California at Berkeley, which is a high spatial resolution interferometer for mid-infrared wavelengths. The instrumentation, its capabilities and performance, data analysis, science program, and future plans are all discussed. The system's use of heterodyne detection, analogous to that of a modern radio interferometer, is also compared with the homodyne or direct methods more commonly encountered in the visible and infrared. The ISI has been operating productively on Mount Wilson for the past 10 years measuring materials immediately surrounding stars and their changes as well as some stellar diameters. The new spectral capabilities described here, a recent increase in baseline length, and the upcoming expansion to a closure-phase imaging array provide important additional types of measurements.

The Project 1640 instrument on the 200-inch Hale telescope at Palomar Observatory is a coronagraphic instrument with an integral field spectrograph at the back end, designed to find young, self-luminous planets around nearby stars. To reach the necessary contrast for this, the PALM-3000 adaptive optics system corrects for fast atmospheric speckles, while CAL, a phase-shifting interferometer in a Mach-Zehnder configuration, measures the quasistatic components of the complex electric field in the pupil plane following the coronagraphic stop. Two additional sensors measure and control low-order modes. These field measurements may then be combined with a system model and data taken separately using a white-light source internal to the AO system to correct for both phase and amplitude aberrations. Here, we discuss and demonstrate the procedure to maintain a half-plane dark hole in the image plane while the spectrograph is taking data, including initial on-sky performance., 9 pages, 7 figures, in Proceedings of SPIE, 8864-19 (2013)

Objectives: Report on Two Case Studies related to Total Knee Arthroplasty Previously Discussed by AKS Members Methods: Case Series Case 1: A 76 year old woman requiring a right total knee replacement in the presence of marked dystrophic calcification affecting the quadriceps tendon on a background of having sustained a post operative quadriceps tendon rupture post left TKR in 2013 Case 2: Management issues related to performing a TKR in a 80 year old woman with a possible past history of TB affecting the joint Conclusion: Both procedures went smoothly and particularly as advice was given by AKS members, these are presented largely for feedback.

A camera operating a Teledyne H2RG in H and Ks bands is under construction at Caltech to serve as a near-infrared tip-tilt sensor for the Keck-1 Laser Guide Star Adaptive Optics system. After imaging the full field for acquisition, small readout windows are placed around one or more natural guide stars anywhere in the AO corrected field of view. Windowed data may be streamed to RAM in the host for a limited time then written to disk as a single file, analogous to a “film strip”, or be transmitted indefinitely via a second fiber optic output to a dedicated computer providing real time control of the AO system. The various windows can be visited at differing cadences, depending on signal levels. We describe a readout algorithm that maximizes exposure duty cycle, minimizes latency, and achieves very low noise by resetting infrequently then synthesizing exposures from Sample Up The Ramp data. To illustrate which noise sources dominate under various conditions, noise measurements are presented as a function of synthesized frame rate and window sizes for a range of detector temperatures. The consequences of spatial variation in noise properties, and dependence on frame rate and temperature are discussed, together with probable causes of statistical outliers.

The first of a new generation of high actuator density AO systems developed for large telescopes, PALM-3000 is optimized for high-contrast exoplanet science but will support operation with natural guide stars as faint as V approx. 18. PALM-3000 began commissioning in June 2011 on the Palomar 200" telescope and has to date over 60 nights of observing. The AO system consists of two Xinetics deformable mirrors, one with 66 by 66 actuators and another with 21 by 21 actuators, a Shack-Hartman WFS with four pupil sampling modes (ranging from 64 to 8 samples across the pupil), and a full vector matrix multiply real-time system capable of running at 2KHz frame rates. We present the details of the completed system, and initial results. Operating at 2 kHz with 8.3cm pupil sampling on-sky, we have achieved a K-band Strehl ratio as high as 84% in approx.1.0 arcsecond visible seeing.

The PALM-3000 upgrade to the Palomar Adaptive Optics system will deliver extreme adaptive optics correction to a suite of three infrared and visible instruments on the 5.1 meter Hale telescope. PALM-3000 uses a 3388-actuator tweeter and a 241-actuator woofer deformable mirror, a wavefront sensor with selectable pupil sampling, and an innovative wavefront control computer based on a cluster of 17 graphics processing units to correct wavefront aberrations at scales as fine as 8.1 cm at the telescope pupil using natural guide stars. Many components of the system, including the science instruments and a post-coronagraphic calibration wavefront sensor, have already been commissioned on the sky. Results from a laboratory testbed used to characterize the remaining new components and verify all interfaces are reported. Deployment to Palomar Observatory is planned August 2010, with first light expected in early 2011.

The Palomar Transient Factory (PTF) is a new fully-automated, wide-field survey conducting a systematic exploration of the optical transient sky. The transient survey is performed using a new 8.1 square degree, 101 megapixel camera installed on the 48-inch Samuel Oschin Telescope at Palomar Observatory. The PTF Camera achieved first light at the end of 2008, completed commissioning in July 2009, and is now in routine science operations. The camera is based on the CFH12K camera, and was extensively modified for use on the 48-inch telescope. A field-flattening curved window was installed, the cooling system was re-engineered and upgraded to closed-cycle, custom shutter and filter exchanger mechanisms were added, new custom control software was written, and many other modifications were made. We here describe the performance of these new systems during the first year of Palomar Transient Factory operations, including a detailed and long term on-sky performance characterization. We also describe lessons learned during the construction and commissioning of the upgraded camera, the photometric and astrometric precision currently achieved with the PTF camera, and briefly summarize the first supernova results from the PTF survey.

The InfraRed Imaging Spectrograph (IRIS) is a first light client science instrument for the TMT observatory that operates as a client of the NFIRAOS facility multi-conjugate adaptive optics system. This paper reports on the concept study and baseline concept design of the On-Instrument WaveFront Sensors (OIWFS) and NFIRAOS interface subsystems of the IRIS science instrument, a collaborative effort by NRC-HIA, Caltech, and TMT AO and Instrument teams. This includes work on system engineering, structural and thermal design, sky coverage modeling, patrol geometry, probe optics and mechanics design, camera design, and controls design., Comment: 17 pages, 12 figures, SPIE7735-285

The Palomar Transient Factory is an automated wide-field survey facility dedicated to identifying a wide range of transient phenomena. Typically, a new 7.5 square degree field will be acquired every 90 seconds with 66% observing efficiency, in g' band when the sky is dark, or in R band when the moon is up. An imaging camera with a 12Kx8K mosaic of MIT/LL CCDs, acquired from CFHT, is being repackaged to fit in the prime focus mounting hub of the Palomar 48-inch Oschin Schmidt Telescope. We discuss how we have addressed the broad range of issues presented by this application: faster CCD readout to improve observing efficiency, a new cooling system to fit within the constrained space, a low impact shutter to maintain reliability at the fast observing cadence, a new filter exchange mechanism, and the field flattener needed to correct for focal plane curvature. The most critical issue was the tight focal plane alignment and co-planarity requirements created by the fast beam and coarse plate scale. We built an optical profilometer system to measure CCDs heights and tilts with 1 μm RMS accuracy.

The currently popular concept and practice on "Wellbore Strengthening" for drilling applications was originated in part from our earlier SPE papers on "A New Approach to Preventing Lost Circulation While Drilling"1 and "Theory of Lost Circulation Pressure".2 Based on our theory and earlier test results, a significant increase in formation fracture resistance could be achieved due to fracture sealing or plugging mechanism induced by a particle "screen-out" effect resulting from the drilling fluid loaded with an adequate amount of narrowly-sized granular materials. We have shown in both our laboratory and field tests that such an increase in formation fracture resistance is particularly valuable in helping the following well operations: 1) drill through depleted zones without losing fluid even when a much higher mud weight (than the normal fracture gradient) is used; 2) strengthen the weaker formations that usually require additional casing strings for protection; 3) avoid lost circulation during cementing operations as the strengthening operation also improves the strength of the cement sheath; and 4) drill high-angle well sections with high mud weights that would normally not be possible due to low formation fracture gradients, etc. We have recently conducted several Wellbore Strengthening treatments using a special type of lost circulation material, in terms of particle size range and loading density, for increased formation fracture resistance (or increased apparent fracture gradient) during normal drilling operations. A wide variety of wellbore problems encountered have been addressed by this technique. Using several field case examples, this paper will provide a review and discussion of the theory, potential, and limits of the wellbore strengthening technique. Lessons learned from our field treatments will also be discussed along with precautions for optimum drilling applications.

The chemokine stromal-derived factor-1 (SDF-1, also known as CXCL12) and its receptor CXCR4 have been implicated in homing of stem cells to the bone marrow and the homing of bone marrow-derived cells to sites of injury. Bone marrow cells infiltrate brain and give rise to long-term resident cells following injury. Therefore, SDF-1 and CXCR4 expression patterns in 40 mice were examined relative to the homing of bone marrow-derived cells to sites of ischemic injury using a stroke model. Mice received bone marrow transplants from green fluorescent protein (GFP) transgenic donors and later underwent a temporary middle cerebral artery suture occlusion (MCAo). SDF-1 was associated with blood vessels and cellular profiles by 24 hours through at least 30 days post-MCAo. SDF-1 expression was principally localized to the ischemic penumbra. The majority of SDF-1 expression was associated with reactive astrocytes; much of this was perivascular. GFP+ cells were associated with SDF-1-positive vessels and were also found in the neuropil of regions with increased SDF-1 immunoreactivity. Most vessel-associated GFP+ cells resemble pericytes or perivascular microglia and the majority of the GFP+ cells in the parenchyma displayed characteristics of activated microglial cells. These findings suggest SDF-1 is important in the homing of bone marrow-derived cells, especially monocytes, to areas of ischemic injury.

The U.C. Berkeley Infrared Spatial Interferometer (ISI), previously described by Hale et al. as a two-telescope stellar interferometer operating in the mid-infrared regime of 9-12 μm, is now testing a recently constructed third telescope and centralized laser local oscillator and beam combining facilities for operation of a three-telescope system with phase closure. This new system will allow the ISI Array to make measurements of stellar photospheric and dust asymmetries in the mid-IR, measurements which have previously been lacking. The new facilities and instrumentation required for three-way heterodyne beam combination and fringe detection, together with techniques for measuring the closure phase, are described. Both hardware and software methods of beam combination are used for producing three simultaneous fringe visibilities and a closure phase measurement. Additionally, the phase closure signal-to-noise of pairwise and of all-in-one beam combination are contrasted.

The U.C. Berkeley Infrared Spatial Interferometer is a two telescope stellar interferometer operating in the 9-12 micron atmospheric window, utilizing heterodyne detection with CO2 laser local oscillators. Science with the ISI has been focused on the measurements of the spatial distribution of dust and molecules around mass-losing late type stars, and more recently precision measurements of stellar diameters in the mid-infrared avoiding molecular lines. During the past few years, a National Science Foundation sponsored program of expansion from two to three telescopes has been underway. This expansion will allow the ISI to make visibility observations on three simultaneous baselines and a measure a closure phase. The third telescope was completed last year and shipped to Mt. Wilson, and more recently a Central Control Facility and Master Laser Oscillator Facility were also completed and recently shipped to Mt. Wilson. In this paper we report progress on this program and highlight some of the most recent astrophysical results.

As physicians, we are trained to respond to emergencies — the more serious the diagnosis, the more quickly we respond. Physicians, as guardians of human health, should be actively engaged in addressing the dangers of global warming, yet we are failing to act in a meaningful and substantive way.

Purpose: We developed a pneumonia guideline at Intermountain Health Care that included admission decision support and recommendations for antibiotic timing and selection, based on the 1993 American Thoracic Society guideline. We hypothesized that guideline implementation would decrease mortality. Subjects and methods: We included all immunocompetent patients >65 years with community-acquired pneumonia from 1993 through 1997 in Utah; nursing home patients were excluded. We compared 30-day mortality rates among patients before and after the guideline was implemented, as well as among patients treated by physicians who did not participate in the guideline program. Results: We observed 28,661 cases of pneumonia, including 7,719 (27%) that resulted in hospital admission. Thirty-day mortality was 13.4% (1,037 of 7,719) among admitted patients and 6.3% (1,801 of 28,661) overall. Mortality rates (both overall and among admitted patients) were similar among patients of physicians affiliated and not affiliated with Intermountain Health Care before the guideline was implemented. For episodes that resulted in hospital admission after guideline implementation, 30-day mortality was 11.0% among patients treated by Intermountain Health Care-affiliated physicians compared with 14.2% for other Utah physicians. Analysis that adjusted by logistic regression for age, sex, rural versus urban residences, and year confirmed that 30-day mortality was lower among admitted patients who were treated by Intermountain Health Care-affiliated physicians (odds ratio [OR]: 0.69; 95% confidence interval [CI]: 0.49 to 0.97; P = 0.04) and was somewhat lower among all pneumonia patients (OR: 0.81; 95% CI: 0.63 to 1.03; P = 0.08). Conclusion: Implementation of a pneumonia practice guideline in the Intermountain Health Care system was associated with a reduction in 30-day mortality among elderly patients with pneumonia.

A novel, fast-switching filterbank system has been incorporated into the Infrared Spatial Interferometer to allow high spectral resolution observations of mid-infrared spectral lines, while precisely calibrating atmospheric fluctuations. This system allows the complex visibility in a spectral line to be measured relative to the continuum with high precision, about 1% in visibility amplitude and a few degrees in visibility phase. The high spectral resolving power (R approximately 100000) and spatial resolution (1/10 arcsecond) allow the formation radii of various polyatomic molecules (e.g., ammonia and silane) to be directly measured. Initial results for carbon star IRC + 10216 and red supergiant VY CMa are presented.

The Infrared Spatial Interferometer (ISI) is an interferometer installed on Mt. Wilson and operating in the 10 μm wavelength region, using heterodyne detection and two movable 1.65 m telescopes. Its general technology and characteristics, recent changes, and observational results are broadly discussed. Some compensation for atmospheric path length fluctuations is demonstrated. Stellar observations show, among other characteristics, that many stars emit gas and dust episodically with times of 10-100 years between events, and that stellar diameters measured in the mid-infrared region are about 10 percent larger than those measured with interferometry using visible light.

It is now widely recognized that inflation distorts corporate taxation. Governments' approaches to coping with these distortions have differed from country to country. In the U.S., for example, use of LIFO accounting for reporting and tax purposes has enabled companies to dampen some of the worst effects of inflation; prior to 1975, practically all other industrial countries required FIFO accounting, which created tremendous liquidity problems for business. On the other hand, the U.S. has lagged in the area of tax incentives for investment. Britain has instituted extremely generous tax incentives, including 100 per cent first-year depreciation on new investment in plant and equipment. Unfortunately, these measures came too late to reverse mounting business conservatism. British business investment has continued to fall in the face of weak demand; the government's expansive monetary policy, intended to produce a takeoff in industrial development, has ended up fueling a real estate boom instead. Since 1975, American corporations have begun to adopt financial policies almost as conservative as those prevalent in Britain. U.S. firms are now emphasizing liquidity rebuilding and balance sheet strength, rather than expansion of plant and equipment. If U.S. tax laws continue to aggravate the problems introduced by inflation, the U.S. too could settle into a long period of permanently slower growth, with a highly conservative business sector providing funds for further expansion of consumption. .

Over 25% of the 80 British psychology departments use microcomputers. This paper summarizes the types of processor, level of system integration, applications, and problems of these users. The Motorola 6800 is by far the most popular processor, but there is a growing number of Z-80 users. Useful microcomputers have been developed from chips, single-board evaluation kits, hobby products, and manufacturers’ development systems. Applications include front-end processing, networking, and stand-alone uses for data logging, process control, and the development of intelligent laboratory tasks. Emphasis is placed on the need to match system packaging and support facilities to the application.

Many special purpose computer languages have been written by psychologists to aid their experimentation. This paper examines some of these languages and considers why they were written, how they were implemented, what special features they offered, and why few have been "acceptable" enough to achieve widespread use. Languages were written to allow process input/output for the experiment, accurate timing, appropriate data structures, asynchronous data storage, operational conveniences such as multiple subject experimentation, conversational or concurrent program development, and suitability for novice users. Widespread use has eluded most languages because of implementation on idiosyncratic hardware, limitations in the language, and too much "single author dependence" giving lack of documentation, support and hence acceptability. It is argued that advances in low cost hardware, with the inevitable spread of computer controlled experimentation particularly amongst novices, and use of modern software development tools, might make the development of new special purpose languages more cost/effective. Alternatively, psychologists should make use of realtime languages developed outside psychology but augmented for easy use by psychologists. To ensure acceptability such languages must not only solve experimental problems but also have good “support”.

To justify investments towards improved traffic operations, engineers and policy-makers need scientific and accurate methods of congestion measurement. However, status-quo methods are limited and/or outdated. Peak-hour analyses are becoming outdated as a sole source of traffic assessment, because they fail to account for changing conditions throughout the year. There has been a movement towards “reliability” modeling, which attempts to capture these annual effects. But due to significant input data and calibration requirements, the reliability models suffer from practicality issues. Next, there have been recent improvements in data-driven intelligent transportation system (ITS) technologies, which identify congestion in real time. However, there is room for improvement in the robustness of performance measures derived from these technologies. Finally, some engineers have compared and ranked congested locations (i.e., bottlenecks) on the basis of experience and judgment. Despite their cost-effectiveness, judgment-based qualitative assessments will lack credibility unless backed by quantitative results. In a recent Federal Highway Administration study, congestion measurement was a primary area of emphasis. This paper discusses project-specific software development, which produced new and innovative performance measures for congestion measurement. It will present concepts and evidence to imply superiority of the proposed new measures. This paper is intended to serve as a preview of a future full journal paper; which will rank ten or more real-world bottlenecks according to new and old performance measures, to demonstrate impacts of the new measures. It is hoped that the new performance measures will be adopted by states and/or commercial products, for a new level of robustness in congestion measurement.

DURING the past 10 years aortocoronary bypass has been widely prescribed to treat angina pectoris. Dysfunction or closure of an aortocoronary-bypass graft is generally suggested by a patient's history, but few if any objective signs are derived from physical examination, electrocardiograms taken with patient at rest or under stress, or studies of regional myocardial perfusion with thallium–201.1 Definitive confirmation of graft closure or stenosis is obtained through postoperative selective angiography of the grafts in question. This invasive procedure is costly, requires hospitalization, and certainly carries some morbidity and mortality. A new technique, described by Lipton et al., 2 that uses computed . . .