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Building and maintaining common ground is vital for effective collaboration in CSCW. Moreover, subtle changes in a CSCW user interface can significantly impact grounding and collaborative processes. Yet, researchers and technology designers lack tools to understand how specific user interface designs may hinder or facilitate communication grounding. In this work, we leverage the well-established theory of communication grounding to develop a visual framework, called Joint Action Storyboards (JASs), to analyze and articulate how interaction minutiae impact the costs of communication grounding. JASs can depict an integrated view of mental actions of collaborators, their physical interactions with each other and the CSCW environment, and the corresponding grounding costs incurred. We present the development of JASs and discuss its various benefits for HCI and CSCW research. Through a series of case studies, we demonstrate how JASs provide an analysis tool for researchers and technology designers and serve as a tool to articulate the impact of interaction minutiae on communication grounding.

ObjectiveSymptom checkers are potentially beneficial tools during pandemics. To increase the use of the platform, perspectives of end users must be gathered. Our objectives were to understand the perspectives and experiences of young adults related to the use of symptom checkers for assessing COVID-19-related symptoms and to identify areas for improvement.MethodsWe conducted semistructured qualitative interviews with 22 young adults (18–34 years of age) at a university in Ontario, Canada. Interviews were audio-recorded, transcribed, and analysed using inductive thematic analysis.ResultsWe identified six main themes related to the decision of using a symptom checker for COVID-19 symptoms: (1) presence of symptoms or a combination of symptoms, (2) knowledge about COVID-19 symptoms, (3) fear of seeking in-person healthcare services, (4) awareness about symptom checkers, (5) paranoia and (6) curiosity. Participants who used symptom checkers shared by governmental entities reported an overall positive experience. Individuals who used non-credible sources reported suboptimal experiences due to lack of perceived credibility. Five main areas for improvement were identified: (1) information about the creators of the platform, (2) explanation of symptoms, (3) personalised experience, (4) language options, and (5) option to get tested.ConclusionsThis study suggests an increased acceptance of symptom checkers due to the perceived risks of infection associated with seeking in-person healthcare services. Symptom checkers have the potential to reduce the burden on healthcare systems and health professionals, especially during pandemics; however, these platforms could be improved to increase use.

This paper summarizes the validation of a modified multi-step phenomenological soot model and an enhanced combustion model used for direct-injection natural gas engines. In this study, a modified phenomenological soot model including the key steps for soot formation, such as particle inception and surface growth, was developed in KIVA-3V to replace the empirical model for use in a glow plug assisted natural gas direct-injection engine. The soot model was integrated with a CANTERA based kinetic model, which employs a recently developed low temperature natural gas mechanism to predict the reactions of some important gaseous species involved in the soot formation, such as acetylene and hydroxyl. The simulated in-cylinder flame propagation process induced by a glow plug was compared to the experimental optical images obtained in an engine-like environment. In addition, both the kinetic model and modified soot model were compared with the experimental emission data to validate their reliability for predicting natural gas engine emission characteristics. The engine combustion efficiencies obtained in simulations and experiments were compared as well. The matched results suggest that the computational models can well predict the natural gas combustion and emission characteristics, and will be suitable for investigating the direct-injection natural gas engine technologies.

Background The aim of this study was to evaluate quetiapine-associated pulmonary complications (PC) in critically injured trauma patients. Methods Injured adults admitted during 2016 to the ICU at a Level I trauma center were analyzed. Outcomes were evaluated by competing risks survival analysis. Results Of 254 admissions, 40 (15.7%) had PC and 214 (84.3%) were non-events. PC patients were more severely injured, had longer hospital stays and were more likely to die. Patients administered quetiapine were more likely to develop PC and acquire PC earlier than those without quetiapine. Quetiapine was a positive risk factor for PC (sHR 2.24, p = 0.013). Stratification by ventilator use revealed non-ventilated patients administered quetiapine had the highest risk for PC (sHR 4.66, p = 0.099). Conclusions Quetiapine exposure in critically injured trauma patients was associated with increased risk of PC. Guidelines for treatment of delirium with quetiapine in critically injured trauma patients should account for this risk.

This paper demonstrates the improvement of a low temperature natural gas (LTNG) mechanism for simulating fuel ignition and combustion emissions under engine-like conditions. The LTNG mechanism was compared and validated in both the simplified zero-dimensional (0D)/one-dimensional (1D) reactors and three-dimensional (3D) engine models. In a 0D premixed constant volume reactor, the LTNG mechanism can more accurately predict the ignition delay than the well-developed GRI-3.0 natural gas mechanism, when the temperature is lower than 1300 K, compared to the experimental data. The results also indicate that the LTNG mechanism can well predict the formation of important carbon-containing gaseous species, such as acetylene and carbon dioxide, and nitrogen oxides emissions under typical engine conditions with and without technologies that implement low temperature combustion. In a 3D computational fluid dynamic model with a range of temperatures and pressures, the matched ignition delay curves from the numerical simulation and the experimental measurements indicate that the LTNG mechanism can improve the prediction of natural gas ignition and combustion compared to the GRI-3.0 mechanism. A further validation conducted in a direct-injection natural gas engine ignited by a hot surface illustrates the reliability of the LTNG mechanism for predicting natural gas ignition and combustion inside compression ignition engines.

The Keck Planet Imager and Characterizer (KPIC) is a purpose-built instrument for high-dispersion coronagraphy in the K and L bands on Keck. This instrument will provide the first high resolution (R>30,000) spectra of known directly imaged exoplanets and low-mass brown dwarf companions visible in the northern hemisphere. KPIC is developed in phases. Phase I is currently at Keck in the early operations stage, and the phase II upgrade will deploy in late 2021. The goal of phase II is to maximize the throughput for planet light and minimize the stellar leakage, hence reducing the exposure time needed to acquire spectra with a given signal-to- noise ratio. To achieve this, KPIC phase II exploits several innovative technologies that have not been combined this way before. These include a 1000-element deformable mirror for wavefront correction and speckle control, a set of lossless beam shaping optics to maximize coupling into the fiber, a pupil apodizer to suppress unwanted starlight, a pupil plane vortex mask to enable the acquisition of spectra at and within the diffraction limit, and an atmospheric dispersion compensator. These modules, when combined with the active fiber injection unit present in phase I, will make for a highly efficient exoplanet characterization platform. In this paper, we will present the final design of the optics and opto-mechanics and highlight some innovative solutions we implemented to facilitate all the new capabilities. We will provide an overview of the assembly and laboratory testing of the sub-modules and some of the results. Finally, we will outline the deployment timeline.

The Keck Planet Imager and Characterizer (KPIC) is a purpose-built instrument to demonstrate new tech- nological and instrumental concepts initially developed for the exoplanet direct imaging field. Located downstream of the current Keck II adaptive optic system, KPIC contains a fiber injection unit (FIU) capable of combining the high-contrast imaging capability of the adaptive optic system with the high dispersion spectroscopy capability of the current Keck high resolution infrared spectrograph (NIRSPEC). Deployed at Keck in September 2018, this instrument has already been used to acquire high resolution spectra (R < 35, 000) of multiple targets of interest. In the near term, it will be used to spectrally characterize known directly imaged exoplanets and low-mass brown dwarf companions visible in the northern hemisphere with a spectral resolution high enough to enable spin and planetary radial velocity measurements as well as Doppler imaging of atmospheric weather phenomena. Here we present the design of the FIU, the unique calibration procedures needed to operate a single-mode fiber instrument and the system performance.

Large displays are often constructed by tiling multiple small displays, creating visual discontinuities from inner bezels that may affect human perception of data. Our work investigates how bezels impact magnitude judgement, a fundamental aspect of perception. Two studies are described which control for bezel presence, bezel width, and user-to-display distance. Our findings form three implications for the design of tiled displays. Bezels wider than 0.5cm introduce a 4--7% increase in judgement error from a distance, which we simplify to a 5% rule of thumb when assessing display hardware. Length judgements made at arm's length are most affected by wider bezels, and are an important use case to consider. At arm's length, bezel compensation techniques provide a limited benefit in terms of judgement accuracy.

International audience; The study of cold or obscured, red astrophysical sources can significantly benefit from adaptive optics (AO) systems employing infrared (IR) wavefront sensors. One particular area is the study of exoplanets around M-dwarf stars and planet formation within protoplanetary disks in star-forming regions. Such objects are faint at visible wavelengths but bright enough in the IR to be used as a natural guide star for the AO system. Doing the wavefront sensing at IR wavelengths enables high-resolution AO correction for such science cases, with the potential to reach the contrasts required for direct imaging of exoplanets. To this end, a new near-infrared pyramid wavefront sensor (PyWFS) has been added to the Keck II AO system, extending the performance of the facility AO system for the study of faint red objects. We present the Keck II PyWFS, which represents a number of firsts, including the first PyWFS installed on a segmented telescope and the first use of an IR PyWFS on a 10-m class telescope. We discuss the scientific and technological advantages offered by IR wavefront sensing and present the design and commissioning of the Keck PyWFS. In particular, we report on the performance of the Selex Avalanche Photodiode for HgCdTe InfraRed Array detector used for the PyWFS and highlight the novelty of this wavefront sensor in terms of the performance for faint red objects and the improvement in contrast. The system has been commissioned for science with the vortex coronagraph in the NIRC2 IR science instrument and is being commissioned alongside a new fiber injection unit for NIRSPEC. We present the first science verification of the system-to facilitate the study of exoplanets around M-type stars.

Hackathons provide rapid, hands-on opportunities to explore innovative solutions to problems, but provide little support to teams in moving those solutions into practice. We explore the use of post-hackathon Learning Circles to connect hackathon teams with key stakeholders, to reflect on prototypes and consider business models. We conducted a qualitative field study with 4 post-hackathon teams on the theme of technology, social isolation, and aging. Our results show that Learning Circles are an effective way to involve stakeholders early in the development process, and to develop a deeper understanding of users, markets, and technology.

Introduction Non-compressible torso hemorrhage accounts for 70% of battlefield deaths. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging technology used to mitigate massive truncal hemorrhage. Use of REBOA on the battlefield is limited by the need for radiographic guided balloon placement. Radiofrequency identification (RFID) is a simple, portable, real-time technology utilized to detect retained sponges during surgery. We investigated the feasibility of RFID to confirm the placement of ER-REBOA. Materials and methods This was a single-arm prospective proof-of-concept experimental study approved by the institutional review board at Naval Medical Center San Diego. The ER-REBOA (Prytime Medical Devices, Inc, Boerne, TX, USA) was modified by placement of a RFID tag. The tagged ER-REBOA was placed in zone I or zone III of the aorta in a previously perfused cadaver. Exact location was documented with X-ray. Five blinded individuals used the RF Assure Detection System (Medtronic, Minneapolis, MN, USA) handheld detection wand to predict catheter tip location from the xiphoid process (zone I) or pubic tubercle (zone III). Results In zone I, actual distance (Da) of the catheter tip was 11 cm from the xiphoid process. Mean predicted distance (Dp) from Da was 1.52 cm (95% CI 1.19-1.85). In zone III, Da was 14 cm from the pubic tubercle. Mean Dp from Da was 4.11 cm (95% CI 3.68-4.54). Sensitivity of detection was 100% in both zones. Specificity (Defined as Dp within 2 cm of Da) was 86% in zone I and 16% in zone III. Conclusions Using RFID to confirm the placement of ER-REBOA is feasible with specificity highest in zone I. Future work should focus on refining this technology for the forward-deployed setting.

Performance and emissions experiments were conducted on a compression-ignition direct-injected natural gas engine (DING) equipped with a shielded glow plug ignition assist system. Tests were conducted at three different intake pressures (34.5 kPag, 68.9 kPag, 103.4 kPag), and four nominal (targeted) equivalence ratios (0.2, 0.3, 0.4, 0.5). CH4, NOx, CO and PM emissions were measured and analyzed, showing that emissions levels are influenced by the DING engine’s combustion modes and intake pressure. Premixed combustion which dominates at low equivalence ratios resulted in higher levels of CH4 and NOx emissions, while mixing-controlled combustion, which develops at higher equivalence ratios, resulted in elevated CO and PM levels. Higher intake pressure was found to improve all emissions levels. The most significant effect was the reduction of PM and CO emissions due to improved fuel charge mixing and air entrainment that results from a pressure-driven momentum increase of the engine’s air swirl field. Brake specific emissions and fuel consumption were estimated and compared against levels reported in the literature for dual-fuel port-injection, and High-Pressure Direct-Injection (HPDI) natural gas engines. The most significant finding was that the DING engine exhibits lower fuel consumption and PM emissions levels when compared to values reported in the literature for HPDI engines. The PM emissions advantage was attributed to a higher proportion of premixed combustion and the absence of a diesel pilot in DING engine operation. Lastly, PM size distributions were analyzed, showing that the DING engine produces PM that is smaller than PM of a conventional diesel engine, but similar to the PM reported in the literature for HPDI engines.

Introduction Deep venous thrombosis (DVT) is considered a preventable complication in trauma patients. Hospitals risk financial penalties for DVT rates above accepted benchmarks. These penalties do not apply to chronic DVT, which develops before admission. Lower-extremity duplex ultrasound (LEDUS) can detect characteristics of thrombus chronicity, allowing differentiation of chronic from acute DVT. The objective of this study was to determine the prevalence of chronic DVT in hospitalized trauma patients. Methods We performed a retrospective review of trauma patients admitted to our Level I trauma center between July 1, 2006 and October 31, 2016 who had a DVT on initial screening LEDUS. Our center utilizes screening and surveillance LEDUS for patients admitted more than 48 hours. Definitions for chronic and acute DVT were extracted from existing literature. Patients with DVT on initial LEDUS underwent review of that LEDUS to assess clot chronicity and were classified as having acute DVT, chronic DVT, or DVT of indeterminate age. Demographic data, medical history, and injury characteristics were collected. Patients with acute DVT and those with chronic DVT were compared. Results The prevalence of chronic DVT among patients with a DVT on initial LEDUS was 29.9%. Chronic DVT occurred in patients who were older and less severely injured. An above-knee component was significantly more common in chronic DVT (65%). Only 34 (41%) of those with chronic DVT reported a history of DVT. Among the patients with chronic DVT, 44 (53%) had a subsequent LEDUS, of whom 4 (9%) showed thrombus progression and 6 (14%) formed a new DVT. Conclusion Lower-extremity duplex ultrasound can identify chronic DVT, which represents nearly 30% of all DVT found on initial screening LEDUS in trauma patients. Those with chronic DVT should receive pharmacologic and mechanical prophylaxis because of the incidence of progression and new acute DVT. They should also be counseled regarding the possibilities of recurrence and chronic venous insufficiency. Level of evidence Diagnostic study, level III.

The field of Computer Supported Cooperative Work has constantly evolved to meet the changing needs of individuals at home, at work, and online. To understand how these changes impacted CSCW research, we systematically reviewed 1209 papers and notes published at the ACM Conference on Computer Supported Cooperative Work between 1990 and 2015. When considered with results from two previous literature reviews, covering 1990 - 1998 and 1998 - 2004 respectively, our analysis provides perspective on 25 years of groupware research. We show that the field has responded to, not anticipated, changes in the computing landscape, long-term trends away from 'systems' and explanatory research, and a lack of bibliographic research that synthesizes findings. Finally, we discuss implications of these trends for CSCW research: how results are synthesized across the field, what kinds of research we value, and how multi-device ecologies are studied.

Background Venous thromboembolism (VTE) in trauma can occur in patients at low risk. Conventional coagulation tests do not predict VTE. Studies investigating thromboelastography (TEG) for VTE risk are conflicting and have not included routine surveillance to detect deep vein thrombosis (DVT). We undertook a prospective study of TEG to evaluate its utility in predicting VTE. Methods We conducted a prospective cohort study on all adult trauma patients admitted to our Level I trauma center from 2013 to 2015. TEG was performed immediately on arrival to the trauma bay. Hypercoagulable TEG was defined as reaction time (R) below, angle (α) above, or maximum amplitude (MA) above reference ranges. All patients received mechanical and/or pharmacologic prophylaxis and were followed up for DVT with our ultrasound surveillance protocol. The primary outcome was lower-extremity DVT. After bivariate analysis of variables related to DVT, those with p values of 0.100 or less were included for multivariate logistic regression. Results A total of 983 patients were evaluated with TEG on admission; of these, 684 (69.6%) received at least one surveillance ultrasound during the index admission. Lower-extremity DVT was diagnosed in 99 (14.5%) patients. Hypercoagulability based on admission TEG occurred in 582 (85.1%) patients. The lower-extremity DVT rate was higher in patients with hypercoagulable TEG than in those without hypercoagulable TEG (15.6% vs. 8%; p = 0.039). Multivariate analysis showed hypercoagulable TEG remained associated with DVT after adjustment for relevant covariates available at admission, with an odds ratio of 2.41 (95% confidence interval, 1.11-5.24; p = 0.026). Conclusion Most trauma patients were hypercoagulable at admission and remained at risk of developing DVT. The rate of DVT doubled in patients with hypercoagulable TEG indices despite prophylaxis. Beyond its current clinical roles, TEG is useful for assessing DVT risk, particularly in patients otherwise perceived to be at low risk. Level of evidence Prognostic study, level II.

This article presents the results of computational studies investigating the ignition of high-pressure natural gas jets in a compression-ignition engine with glow plug ignition assist. The simulation was conducted using a KIVA-3V-based three-dimensional engine model, along with an improved fuel injector model, a detailed cut-off glow plug shield model and a modified two-step methane reaction mechanism, to simulate the natural gas injection and ignition. The simulated results demonstrate the significance of using a shield for the glow plug. Compared to an unshielded (bare) glow plug, the shield not only reduces the heat loss from the hot glow plug surface to the cold intake air charge and the cold injected gas jet but also traps the fuel mixture to increase its residence time adjacent to the hot surface. Over a representative range of heavy-duty diesel engine operating conditions, a shielded glow plug greatly improves the natural gas engine performance and provides reliable ignition, while an unshielded glow plug can only be optimized for specific conditions. The understanding of glow plug shield behavior gained from the simulations suggests avenues for improved shield designs that would yield further reduced ignition delays.

The Brain Trauma Foundation guidelines provide indications for neurosurgical intervention in traumatic brain injury (TBI) with moderate or severe intracranial hemorrhage (ICH). In TBI patients with less severe ICH, the utility of neurosurgical consultation remains unclear. We sought to determine if routine neurosurgical consultation is necessary for mild blunt TBI patients with ICH. A retrospective cohort study was conducted on 500 consecutive blunt TBI patients aged 15 years or older with Glasgow Coma Scale score of ≥13 and ICH on initial head computed tomography admitted to a Level I trauma center over 28 months. Outcomes were neurosurgical intervention (craniotomy, craniectomy, ventriculostomy, or intracranial pressure monitor placement) and in-hospital mortality. Statistical significance was assessed at a p < 0.05. Of 500 patients, 49 (9.8%) underwent neurosurgical intervention. Neurosurgical intervention was more frequent in male patients (75.5% vs. 61.2%, p = 0.049), patients with higher head Abbreviated Injury Scale score (4.7 vs. 3.8, p < 0.0001), patients with an abnormal initial neurological examination (30.6% vs. 12.6%, p = 0.001), or patients with skull fracture (28.6% vs. 16.0%, p = 0.026) and was associated with higher mortality (8.2% vs. 2.0%, p = 0.010). Neurosurgical intervention was not associated with intoxication, preinjury antiplatelet/anticoagulation agents, or progression of ICH on second head computed tomography. Neurosurgical consultation was documented in 466 patients (93.2%). For patients without neurosurgical intervention, consultation did not change management. Routine neurosurgical consultation for blunt TBI with ICH seems unnecessary, regardless of intoxication or preinjury antiplatelet or anticoagulation therapy. A more selective approach is warranted to decrease hospital charges and optimize use of neurosurgical consultation. Care management study, level IV.

With the increasing need to teach programming to novices using collaborative methods like pair programming, it is important to understand how different input devices can help support collaborative learning. In this paper we present Multi-Device Grace, the first application to explore block-based programming in a cross-device environment consisting of digital tabletops, mobile tablets, and laptops. We conducted a user study $(n =18)$ to explore how cross-device environments can support co-located collaborative block-based programming. The study used Tiled Grace, an existing block-based programming language, and our extensions: Tabletop Grace (designed for tabletops) and Mobile Grace (designed for tablets). Our results show that the majority of participants felt they were able to collaborate quickly and easily, and the cross device interaction would be particularly beneficial in an education setting. Fig. 1.Multi-Device Grace: multiple novice programmers simultaneously working together on different devices (laptop, mobile tablet, and digital tabletop) within different independent workspaces to develop a new blocks-based program.

The Keck Planet Imager and Characterizer comprises of a series of upgrades to the Keck II adaptive optics system and instrument suite to improve the direct imaging and high resolution spectroscopy capabilities of the facility instruments NIRC2 and NIRSPEC, respectively. Phase I of KPIC includes a NIR pyramid wavefront sensor and a Fiber Injection Unit (FIU) to feed NIRSPEC with a single mode fiber, which have already been installed and are currently undergoing commissioning. KPIC will enable High Dispersion Coronagraphy (HDC) of directly imaged exoplanets for the first time, providing potentially improved detection significance and spectral characterization capabilities compared to direct imaging. In favorable cases, Doppler imaging, spin measurements, and molecule mapping are also possible. This science goal drives the development of phase II of KPIC, which is scheduled to be deployed in early 2020. Phase II optimizes the system throughput and contrast using a variety of additional submodules, including a 952 element deformable mirror, phase induced amplitude apodization lenses, an atmospheric dispersion compensator, multiple coronagraphs, a Zernike wavefront sensor, and multiple science ports. A testbed is being built in the Exoplanet Technology Lab at Caltech to characterize and test the design of each of these submodules before KPIC phase II is deployed to Keck. This paper presents an overview of the design of phase II and report on results from laboratory testing., 12 pages; 11 figures; to appear in Proceedings of the SPIE, Techniques and Instrumentation for Detection of Exoplanets IX, Vol. 11117

The Keck Planet Imager and Characterizer (KPIC) is an upgrade to the Keck II adaptive optics system enabling high contrast imaging and high-resolution spectroscopic characterization of giant exoplanets in the mid-infrared (2-5 microns). The KPIC instrument will be developed in phases. Phase I entails the installation of an infrared pyramid wavefront sensor (PyWFS) based on a fast, low-noise SAPHIRA IR-APD array. The ultra-sensitive infrared PyWFS will enable high contrast studies of infant exoplanets around cool, red, and/or obscured targets in star forming regions. In addition, the light downstream of the PyWFS will be coupled into an array of single-mode fibers with the aid of an active fiber injection unit (FIU). In turn, these fibers route light to Keck's high-resolution infrared spectrograph NIRSPEC, so that high dispersion coronagraphy (HDC) can be implemented for the first time. HDC optimally pairs high contrast imaging and high-resolution spectroscopy allowing detailed characterization of exoplanet atmospheres, including molecular composition, spin measurements, and Doppler imaging. We will provide an overview of the instrument, its science scope, and report on recent results from on-sky commissioning of Phase I. We will discuss plans for optimizing the instrument to seed designs for similar modes on extremely large telescopes.

We present the design and evaluation of Scalebridge, an educational game that teaches children the mathematical skill of proportional reasoning. We also propose an adaptive level difficulty model that uses low-cost brain-computer interface device to modulate difficulty of the game based on the player's focus. We show that the game achieves the educational learning outcome of developing proportional reasoning skill both in the adaptive and in the non-adaptive version of game.

The influences of different fuel injection strategies on emission characteristics in a glow plug assisted direct-injection natural gas engine were computationally investigated by a KIVA-3V engine model. A detailed chemical kinetic model and a phenomenological soot model were implemented in the simulation to predict the formation of engine emissions. The simulation reveals that the sac volume of the fuel injector is one of the major contributors to the methane emissions, and the use of a bigger injector nozzle and shorter injection duration can reduce the fuel storage inside the sac volume. In addition, the glow plug shield will trap some fuel mixture and induce relatively rich combustion that contributes a significant amount to both of methane emission and soot particles. Additional openings in the upper part of the glow plug shield may be needed to improve the flow exchange between the shield and the combustion chamber, in order to reduce the emission formation. Further simulation suggests that different fuel injection strategies, such as changing the injection angle and using different injector nozzle sizes associated with different injection durations, could affect the fuel injection, flame propagation and then emission formation inside the glow plug shield and combustion chamber. An optimized fuel injection strategy thereby has potential of reducing the local emission formation inside the glow plug shield and its contribution to the final combustion emissions.

Use of a shielded glow plug (GP) for ignition assist enables operation of direct-injection engines on 100% natural gas. The shield improves ignition performance by reducing GP cooling from impinging intake air and injected natural gas jets and by trapping mixture adjacent to the hot surface thereby increasing residence time. After ignition, flame must propagate out of the shield to consume fuel in the combustion chamber. The number, size, and position of openings in the GP shield determines the path of flame propagation from the shield. This study computationally investigated the performance of a shield with multiple openings arranged in a diamond pattern compared to a basic single-opening shield. A KIVA-3V based engine model coupled with the CANTERA kinetics package was used and incorporated a multi-step phenomenological soot model to predict the formation of soot particles. The results illustrate that the new multi-opening shield has significant influence on both the flow of injected fuel into the shield and the flame propagation out of the shield. The multi-opening shield design reduces the fuel flow into the shield during injection and improves fuel distribution within the shield compared to the single-opening shield. With the multi-opening shield, the initial flame propagating out moves towards the combustion chamber wall to consume the adjacent fuel jets before spreading in the swirl direction. Both shields result in comparable pressure rise, but the multi-opening shield reduces overall soot emissions by 46.6%, with similar methane emissions, compared to the single-opening shield.

This paper studies the influences of different fuel injection strategies on flame propagation and combustion characteristics in a glow plug assisted direct-injection natural gas engine. Our previously existing version of the KIVA-3V CFD code incorporates a model of internal flows in the gaseous fuel injector and also a detailed model of the glow plug and its shield. This study was conducted by using the KIVA-3V code with added improved emissions models, including a detailed kinetic chemical model and a modified phenomenological soot model. In the simulation, a low temperature natural gas mechanism is selected to estimate the gaseous species, and acetylene was chosen as the key species to model the soot formation. The simulation indicated that the fuel injection duration, injector nozzle size and injection angle can affect the natural gas combustion characteristics. Generally, shorter injection duration reduces both peak cylinder pressure and emissions in the natural gas engine; however, the natural gas flame propagation cannot be maintained once the injected fuel mass is lower than a limit. The simulation also reveals that the injector nozzle size highly affects the natural gas combustion by inducing diffusion combustion for a small diameter nozzle and partially premixed combustion for a large diameter nozzle. Compared to a large nozzle, a small nozzle results in a faster pressure rise with more engine emissions and lower combustion efficiency. The fuel injection angle can influence natural gas combustion characteristics by affecting the flame propagation out of the glow plug shield in the initial combustion stage.

12035 Background: The ASCO 2018 Geriatric Oncology Guidelines support the broad application of GA to risk-stratify patients age ≥65 undergoing cancer-directed therapy. Despite this, GA has not been widely adopted due largely to perceived time and resource constraints. We administered an abbreviated GA by medical assistants (MAs) in an outpatient oncology clinic to explore its feasibility and correlation with adverse events. Methods: This is a single-institution, retrospective study of adults establishing oncology care at an academic medical center from 11/2016-4/2017. MAs completed an abbreviated GA of well-validated tests. Cognitive function was screened by the Mini-Cog (score < 4) and physical function by the Five Times Sit-to-Stand Test (FTSST ≥ 15 seconds). Patient-reported Outcomes (PRO) screened for malnutrition by the Malnutrition Screening Test (MST ≥ 2), for vulnerability by Vulnerable Elders Survey (VES-13 ≥ 3) and for depression by Patient Health Questionnaire-4 (PHQ-4 > 2). The first result within 3 months of the initial visit was used for analysis. ED visits, inpatient admissions and early death, defined as within the first 6 months from the initial visit, were collected from the electronic medical record. GA results and baseline characteristics were modeled for these events using univariate logistic regression. Multivariable regression was performed when univariate regression revealed at least 2 factors with p< 0.1. Results: New patients 65+ years (n=304, median age 72) established care in our practice during this six-month period. Nearly all patients (n=285, 94%) completed at least one GA test. Fewer patients completed the Mini-Cog and FTSST (60% completed) compared to the PRO screenings (83-90% completed). Those with any positive GA screening test were nearly 3 times as likely to die within 6 months of their initial outpatient visit compared with those with no deficits (OR 2.95, 95% CI 1.11-9.30). Those with FTSST ≥ 15 sec or unable to complete were more likely to have an ED visit within 6 months (OR 2.40, 95%CI 1.04-5.46).No other individual screening test had a statistically significant association with adverse events. Conclusions: An abbreviated version of GA completed by MAs can be incorporated into new oncology patient visits for all older adults, and those with any abnormalities on screening tests had a higher likelihood of early death. [Table: see text]

Consumer feedback is collected in many industries, including in healthcare where patient feedback contributes to a higher quality of care. Current collection methods include complaints, local surveys, and patient stories, but these methods yield low participation at high costs. Providers need affordable and effective ways to collect feedback, and smartphone applications present as suitable solutions. However, previous research shows that patients are hesitant to provide smartphone-based feedback in a care setting due to perceived risks and apparent futility of expecting change as a result. We will conduct a study to observe consumer behaviour using smartphones to provide service feedback in healthcare spaces versus non-healthcare spaces. We will identify addressable barriers that impact the adoption of smartphone technology to gather patient experience data in health care spaces.

One of the goals of high-contrast imaging is to reach contrasts of 10^(-10) at small inner working angles to directly image Earth-like exoplanets around solar-type stars. In most imaging systems, a deformable mirror (DM) in the pupil plane can correct for phase errors but surface errors in out-of-pupil optics get coupled into amplitude errors which can only be controlled with a second, out of pupil, DM. Furthermore, correcting static errors introduced by the optics can take up valuable DM stroke. Thus, minimizing the wavefront error within the system is critical to reaching high contrast levels. For example, the High Contrast Spectroscopy for Segmented Telescopes Testbed (HCST) in the Exoplanet Technologoy lab at Caltech aims to develop exoplanet imaging technologies down to small inner working angles (< 3λ/D) which requires an RMS wavefront error of less than 10 nm per optic to achieve a contrast of 10^(−5) with the DM flattened. While aligning HCST, it was determined that despite the excellent surface quality of all the optics, the mounts were introducing significant wavefront errors. Here we assess the effect of mount-induced wavefront errors that can rapidly consume the wavefront budget of a high-contrast system. We also present the method used to mitigate this effect within HCST such that a mean contrast of 6 × 10^(-6) from 3-10λ/D was achieved with a vortex coronagraph and flattened DM.

A near-infrared, high order pyramid wavefront sensor will be implemented on the Keck telescope, with the aim of providing high resolution adaptive optics correction for the study of exoplanets around M-type stars and planet formation in obscured star forming regions. The pyramid wavefront sensor is designed to support adaptive optics correction of the light to an imaging vortex coronagraph and to a fiber injection unit that will feed a spectrograph. We present the opto-mechanical design of the near-infrared pyramid wavefront sensor, the optical performance, and the alignment strategy. The challenges of designing the assembly, as well as a fiber injection unit, to fit into the limited available space on the Keck adaptive optics bench, will also be discussed., Adaptive Optics Systems VI, June 10-15, 2018, Austin, TX, USA, Series: Proceedings of SPIE; no. 10703

Imaging Earth-like exoplanets with future space telescopes will require a coronagraph instrument that is capable of creating a dark zone in the starlight at the image plane that is ten orders of magnitude fainter than the off-axis image of the host star. What is more, the coronagraph must simultaneously provide a stable dark zone and high throughput over the angular separations that correspond to habitable zones around nearby Sun-like stars (~10-100 milliarcseconds). Since the pupils of most large-aperture space telescope architectures are likely to be obstructed by secondary mirrors, spider support structures, and gaps between mirror segments, the coronagraph optics must also be specially tailored to passively suppress starlight diffracted from the obstructions and discontinuities in the telescope pupil. Here, we demonstrate an apodized vortex coronagraph optimized for an off-axis segmented telescope on the new High Contrast Spectroscopy Testbed for Segmented Telescopes (HCST) at Caltech. The coronagraph consists of a microdot apodizer, a liquid crystal vortex phase mask in the focal plane, and a Lyot stop. The microdot apodizer is an AR-coated glass window with 10um gold microdots to be used in reflection around lambda=800nm. We describe the HCST optical system; the apodizer optimization, fabrication, and metrology procedures; and present end-to-end testbed results of the coronagraph coupled with a 32x32 Boston Micromachines deformable mirror for wavefront control. We aim to achieve a dark zone 10^-7 times fainter than the simulated host star over a wavelength range of 800±40nm in Spring 2018. Finally, we will outline future plans to demonstrate coronagraph concepts for centrally obscured telescopes.

Various surgical techniques exist to create the gastrojejunostomy during laparoscopic Roux-en-Y gastric bypasses (LRYGB). A hand-sewn anastomosis (HSA) and circular-stapled anastomosis (CSA) are both common techniques. We hypothesized that the CSA was associated with a greater incidence of anastomotic complications. As a secondary aim, we sought to determine if weight loss varied by technique.This study is a retrospective review of patients who underwent primary LRYGB at the Medical College of Wisconsin from January 2010 to December 2011. Procedures were performed by one of 2 surgeons, each with a preferred gastrojejunostomy technique. Clinical information and patient outcomes were followed up to one year.A total of 190 patients underwent LRYGB during the study interval. The majority of patients underwent HSA. Forty-one of 190 (21.6%) patients experienced one or more complications. Most complications were Clavien Classification Grade III and were experienced within 30 days of surgery in 3 (2.2%) HSA patients and 6 (10.9%) CSA patients (P = .02). Anastomotic complications occurred more frequently with the CSA technique (marginal ulcer 5.5% CSA versus .7% HSA; P = .04 and stenosis 16.4% CSA versus 3% HSA; P = .01). There were no gastrojejunostomy leaks in this series. Operative time was significantly longer in HSA patients (204 minutes HSA versus 166 minutes CSA; P.01), but length of hospital stay did not differ. Weight loss at 12 months was similar between techniques (69.4% percent excess BMI lost (EBMIL) HSA versus 76.6% EBMIL CSA; P = .11). No patients were lost to follow-up at 30 days. Thirty-five patients (19%) were lost to follow-up by one year.The CSA technique of gastrojejunostomy in gastric bypass is associated with a higher rate of nonlife threatening anastomotic complications than the HSA technique. Operative times are significantly longer for HSA, but length of hospital stay (LOS) and long-term weight loss are equivalent.

Cross-device environments (XDEs) have been developed to support a multitude of collaborative activities. Yet, little is known about how different cross-device interaction techniques impact group collaboration; including their impact on independent and joint work that often occur during group work. In this work, we explore the impact of two XDE data browsing techniques: TOUCH and TILT. Through a mixed-methods study of a collaborative sensemaking task, we show that TOUCH and TILT have distinct impacts on how groups accomplish, and shift between, independent and joint work. Finally, we reflect on these findings and how they can more generally inform the design of XDEs. Natural Sciences and Engineering Council of Canada (NSERC)

Whole-metagenome sequencing (WMS) has emerged as a powerful tool to assess potential public health risks in marine environments by measuring changes in microbial community structure and function in uncultured bacteria. In addition to monitoring public health risks such as antibiotic resistance determinants, it is essential to measure predictors of microbial variation in order to identify natural versus anthropogenic factors as well as to evaluate reproducibility of metagenomic measurements.This study expands our previous metagenomic characterization of Puget Sound by sampling new nearshore environments including the Duwamish River, an EPA superfund site, and the Hood Canal, an area characterized by highly variable oxygen levels. We also resampled a wastewater treatment plant, nearshore and open ocean sites introducing a longitudinal component measuring seasonal and locational variations and establishing metagenomics sampling reproducibility. Microbial composition from samples collected in the open sound were highly similar within the same season and location across different years, while nearshore samples revealed multi-fold seasonal variation in microbial composition and diversity. Comparisons with recently sequenced predominant marine bacterial genomes helped provide much greater species level taxonomic detail compared to our previous study. Antibiotic resistance determinants and pollution and detoxification indicators largely grouped by location showing minor seasonal differences. Metal resistance, oxidative stress and detoxification systems showed no increase in samples proximal to an EPA superfund site indicating a lack of ecosystem adaptation to anthropogenic impacts. Taxonomic analysis of common sewage influent families showed a surprising similarity between wastewater treatment plant and open sound samples suggesting a low-level but pervasive sewage influent signature in Puget Sound surface waters. Our study shows reproducibility of metagenomic data sampling in multiple Puget Sound locations while establishing baseline measurements of antibiotic resistance determinants, pollution and detoxification systems. Combining seasonal and longitudinal data across these locations provides a foundation for evaluating variation in future studies.

Background: Smartphones are positioned to transform the way health care services gather patient experience data through advanced mobile survey apps which we refer to as smart surveys. In comparison with traditional methods of survey data capture, smartphone sensing survey apps have the capacity to elicit multidimensional, in situ user experience data in real time with unprecedented detail, responsiveness, and accuracy. Objective: This study aimed to explore the context and circumstances under which patients are willing to use their smartphones to share data on their service experiences. Methods: We conducted in-person, semistructured interviews (N=24) with smartphone owners to capture their experiences, perceptions, and attitudes toward smart surveys. Results: Analysis examining perceived risk revealed a few barriers to use; however, major potential barriers to adoption were the identity of recipients, reliability of the communication channel, and potential for loss of agency. The results demonstrate that the classical dimensions of perceived risk raised minimal concerns for the use of smartphones to collect patient service experience feedback. However, trust in the doctor-patient relationship, the reliability of the communication channel, the altruistic motivation to contribute to health service quality for others, and the risk of losing information agency were identified as determinants in the patients’ adoption of smart surveys. Conclusions: On the basis of these findings, we provide recommendations for the design of smart surveys in practice and suggest a need for privacy design tools for voluntary, health-related technologies.

The High Contrast Spectroscopy Testbed for Segmented Telescopes (HCST) at Caltech is aimed at filling gaps in technology for future exoplanet imagers and providing the U.S. community with an academic facility to test components and techniques for high contrast imaging with future segmented ground-based telescope (TMT, E-ELT) and space-based telescopes (HabEx, LUVOIR). The HCST will be able to simulate segmented telescope geometries up to 1021 hexagonal segments and time-varying external wavefront disturbances. It also contains a wavefront corrector module based on two deformable mirrors followed by a classical 3-plane single-stage corona- graph (entrance apodizer, focal-plane mask, Lyot stop) and a science instrument. The back-end instrument will consist of an imaging detector and a high-resolution spectrograph, which is a unique feature of the HCST. The spectrograph instrument will utilize spectral information to characterize simulated planets at the photon-noise limit, measure the chromaticity of new optimized coronagraph and wavefront control concepts, and test the overall scientific functions of high-resolution spectrographs on future segmented telescopes.

Inguinal hernia repair, laparoscopic or open, is one of the most frequently performed operations in general surgery. Postoperative urinary retention (POUR) can occur in 0.2-35 % of patients after inguinal hernia repair. The primary objective of this study was to determine the incidence of POUR after inguinal hernia repair. As a secondary goal, we sought to determine whether perioperative and patient factors predicted urinary retention.This study is a retrospective review of patients who underwent inguinal hernia repair with synthetic mesh at the Medical College of Wisconsin from January 2007 to June 2012. Procedures were performed by four surgeons. Clinical information and perioperative outcomes were collected up to hospital discharge. Urinary retention was defined as need for urinary catheterization postoperatively.A total of 192 patients were included in the study (88 bilateral, 46 %) and (104 unilateral, 54 %). The majority of subjects (76 %) underwent laparoscopic repair. The overall POUR rate was 13 %, with 25 of 192 patients requiring a Foley catheter prior to discharge. POUR was significantly associated with bilateral hernia repairs (p = 0.04), BMI ≥ 35 kg/m(2) (p = 0.05) and longer operative times (p = 0.03). Based on odds ratio (OR) estimates, for every 10-min increase in operative time, an 11 % increase in the odds of urinary retention is expected (OR 1.11, CI 1.004-1.223; p = 0.04). For every 10-min increase in operative time, an 11 % increase in POUR is expected.Bilateral hernia repairs, BMI ≥ 35 kg/m(2), and operative time are significant predictors of POUR. These factors are important to determine potential risk to patients and interventions such as strict fluid administration, use of catheters, and potential premedication.

The United States produces significant quantities of waste biomass from wastewater treatment, food production, food services, and landscape and wood debris. This waste contains essential re...

Coupling a high-contrast imaging instrument to a high-resolution spectrograph has the potential to enable the most detailed characterization of exoplanet atmospheres, including spin measurements and Doppler mapping. The high-contrast imaging system serves as a spatial filter to separate the light from the star and the planet while the high-resolution spectrograph acts as a spectral filter, which differentiates between features in the stellar and planetary spectra. The Keck Planet Imager and Characterizer (KPIC) located downstream from the current W. M. Keck II adaptive optics (AO) system will contain a fiber injection unit (FIU) combining a high-contrast imaging system and a fiber feed to Keck’s high resolution infrared spectrograph NIRSPEC. Resolved thermal emission from known young giant exoplanets will be injected into a single-mode fiber linked to NIRSPEC, thereby allowing the spectral characterization of their atmospheres. Moreover, the resolution of NIRSPEC (R = 37,500) is high enough to enable spin measurements and Doppler imaging of atmospheric weather phenomenon. The module will be integrated and tested at Caltech before being transferred to Keck in 2018.

Two observations drawn from a thoroughly validated direct numerical simulation of the canonical spatially developing, zero-pressure gradient, smooth, flat-plate boundary layer are presented here. The first is that, for bypass transition in the narrow sense defined herein, we found that the transitional-turbulent spot inception mechanism is analogous to the secondary instability of boundary-layer natural transition, namely a spanwise vortex filament becomes a [Formula: see text] vortex and then, a hairpin packet. Long streak meandering does occur but usually when a streak is infected by a nearby existing transitional-turbulent spot. Streak waviness and breakdown are, therefore, not the mechanisms for the inception of transitional-turbulent spots found here. Rather, they only facilitate the growth and spreading of existing transitional-turbulent spots. The second observation is the discovery, in the inner layer of the developed turbulent boundary layer, of what we call turbulent-turbulent spots. These turbulent-turbulent spots are dense concentrations of small-scale vortices with high swirling strength originating from hairpin packets. Although structurally quite similar to the transitional-turbulent spots, these turbulent-turbulent spots are generated locally in the fully turbulent environment, and they are persistent with a systematic variation of detection threshold level. They exert indentation, segmentation, and termination on the viscous sublayer streaks, and they coincide with local concentrations of high levels of Reynolds shear stress, enstrophy, and temperature fluctuations. The sublayer streaks seem to be passive and are often simply the rims of the indentation pockets arising from the turbulent-turbulent spots.

This paper presents a numerical study on fuel injection, ignition, and combustion in a direct-injection natural gas (DING) engine with ignition assisted by a shielded glow plug (GP). The shield geometry is investigated by employing different sizes of elliptical shield opening and changing the position of the shield opening. The results simulated by KIVA-3V indicated that fuel ignition and combustion is very sensitive to the relative angle between the fuel injection and the shield opening, and the use of an elliptical opening for the glow plug shield can reduce ignition delay by 0.1–0.2 ms for several specific combinations of the injection angle and shield opening size, compared to a circular shield opening. In addition, the numerical results also revealed that the natural gas ignition and flame propagation will be delayed by lowering a circular shield opening from the fuel jet center plane, due to the blocking effect of the shield to the fuel mixture, and hence, it will reduce the DING engine performance by causing a longer ignition delay.

Purpose To define maximum tolerated dose (MTD), toxicities, and pharmacodynamics of capecitabine, oxaliplatin, bevacizumab, and everolimus in advanced solid tumor patients. Design This was a standard “3 + 3” dose-escalation trial. All subjects received bevacizumab 7.5 mg/kg on day 1 of each cycle. Doses for capecitabine, oxaliplatin and everolimus were modified per dose limiting toxicity (DLT). Baseline and on-treatment plasma biomarkers were analyzed. Archived tumor mRNA levels were evaluated for NRP1, NRP2 and VEGF-A isoforms. Results Twenty-nine patients were evaluable for toxicity and 30 for efficacy. Two DLTs were observed in cohort 1 and one DLT each was observed in cohort −1 and −1b. Grade ≥3 toxicities included neutropenia, hypertension, perforation/fistula/hemorrhage, hypertriglyceridemia, diarrhea, and thromboembolism. Twelve subjects experienced partial response (PR); 12 had stable disease as best response. Three of seven chemorefractory metastatic colorectal cancer (mCRC) subjects experienced PR; 8 of 15 chemonaive mCRC subjects experienced PR. Plasma TβRIII and IL-6 increased on treatment but without correlation to outcome. Increased VEGF165 levels significantly correlated with longer progression free survival. Conclusions Everolimus with full dose capecitabine, oxaliplatin, and bevacizumab had unacceptable toxicity. MTD was: everolimus 5 mg daily; capecitabine 680 mg/m2 BID days 1–14; oxaliplatin 100 mg/m2 and bevacizumab 7.5 mg/kg, day 1. Activity was noted in mCRC.

Obesity is a recognized risk factor for gastroesophageal reflux disease (GERD). Traditional antireflux surgery (fundoplication) may not be appropriate in the morbidly obese, especially when other effective alternatives exist (bariatric surgery). A 13-item survey was designed to elicit professional opinions regarding the treatment of medically refractory GERD in obese patients. Members of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) were randomly selected and emailed a link to an online survey. A total of 550 surgeons were contacted via email, and 92 (17 %) completed the survey. Of the respondents, 88 % perform laparoscopic antireflux surgery, 63 % perform bariatric surgery, and 59 % perform both. Overall, 77 % completed a minimally invasive surgery fellowship. In response to the question “Would you perform a laparoscopic fundoplication in a patient with medically refractory GERD and a BMI of ‘X’?” surgeons were less likely to offer fundoplication at a higher body mass index (BMI). The majority of respondents felt that laparoscopic Roux-en-Y gastric bypass was the best option (91 %), followed by laparoscopic sleeve gastrectomy (6 %). Many had a morbidly obese patient with a primary surgical indication of GERD denied a bariatric procedure by their insurance company (57 %), and 35 % of those surgeons chose to do nothing rather than subject the patient to a fundoplication. Respondents uniformly felt that bariatric surgery should be recognized as a standard surgical option for treating GERD in the obese (96 %). When surgical treatment of GERD is indicated in an obese patient, bariatric surgery is the optimal approach, in the opinion of surgeons responding to our survey. Unfortunately, third-party payers often decline to provide benefits for a bariatric procedure for this indication. Additional data is necessary to confirm our belief that the opinions elicited through this survey are consistent with the standard of care as defined by the medical community.

Chagas disease is caused by the parasite Trypanosoma cruzi. The disease is difficult to detect because of the asymptomatic pathogenesis after infection. Chagas disease is endemic throughout much of Mexico, Central America, and South America, but human migration patterns are bringing the pathogen to the United States. The disease currently affects 16 to 18 million people with approximately 50000 deaths annually in these countries. In the United States, national screening of the blood supply was instituted in early 2007, and more than 1000 donors with T cruzi infection have been identified within the past 3 years of testing. It was observed that out of the 58 organ procurement organizations in the United States, only 4 required mandatory testing of every donor for Chagas disease. It was estimated that as of 2009, approximately 409 000 residents are living with Chagas disease, and in a 22-year span, approximately 300 patients may have contracted Chagas disease through transplant. Proposed solutions to the current testing method include automatic testing based on the medical social history questionnaire, testing of all recipients for Chagas disease, testing all persons of Latin descent, or testing of all organ donors.

Objectives/Hypothesis This study is undertaken to determine if the presence or absence of multiseptated frontal sinuses is associated with the presence or absence of supraorbital ethmoid cells (SOECs). Study Design Analysis of prospectively collected data. Methods Sixty consecutive patients with chronic rhinosinusitis were identified from a prospectively collected database at a tertiary-referral institution as having full-sinus computed tomography (CT) scans. Preoperative or initial CT scans of the sinuses were reviewed, specifically identifying the presence or absence of supraorbital ethmoid air cells (SOECS) and frontal sinus multiseptated sections on coronal imaging. Statistical analysis was performed using the chi-squared test to evaluate any association between the two structural entities. Results Sixty total patients were identified, for a total of 120 sides. Of the 61 sides with frontal septations, 43 (70%) had SOECs present and 18 (30%) did not. Of the 59 sides without frontal sinus septations, 13 (22%) had SOECs present and 46 (78%) did not (chi squared = 28.3; P = 0.0000001). The difference in the presence of supraorbital ethmoid cells between whites and blacks is also statistically significant (chi squared = 4.23; P = 0.040). Conclusion The presence of frontal sinus septations appears to be significantly associated with and predictive of the presence of supraorbital ethmoid cells. Thus, identifying frontal sinus septations on sinus CT is implicated with more complex anatomy of the frontal recess. Level of Evidence NA. Laryngoscope, 123:2090–2093, 2013