Browsing by Author "Lewis, Julia"

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    Demonstrating Air Emissions Reductions Through Energy Efficiency Retrofits on Maersk Line G-Class Vessels
    (2017-04-28) Cooper, Geoffrey; Lozier, Benjamin; Lewis, Julia
    Maersk Line has committed to investing $1 billion over five years to retrofit around 100 vessels to increase capacity and reduce fuel consumption. $125 million of that investment was used to retrofit 12 G-class vessels. This Radical Retrofit (RR) program included redesigning the bulbous bow of each vessel, replacing existing propellers with more efficient models, and derating the main engines to make them more efficient at lower speeds. It also involved raising the bridge to increase each ship’s capacity from about 9,500 twenty-foot equivalent units (TEUs) to about 11,000 TEUs. The objective of this report is to support Maersk’s efforts on the San Pedro Bay Ports Technology Advancement Program, during its early stages, by assessing the various sources of data, developing recommendations, and designing a preliminary model for assessing the emissions reductions associated with the RR on each vessel. The two main sources of data used in this project are the Maersk Ship Performance System (MSPS) and the Control, Alarm, and Monitoring System (CAMS). The two main differences between these sources of data are the frequency in which the data is reported and the method in which it is reported. Using a series of linear regressions comparing MSPS data pre- and post-RR shows that the class average fuel consumption improvement is 19% (p-value<0.05); however, the individual models show substantial variance between the vessels. The estimates for each vessel range from 5.8% to 33.3%; and these coefficients are all statistically significant at the 0.05 level except for one vessel—the Gjertrud. However, using CAMS data to assess the uncertainty of the MSPS data shows that there is a high level of uncertainty associated with using MSPS data. The final section of this report makes three recommendations on how Maersk Line can include environmental considerations in the new Performance Platform. The recommendations are: 1) develop an emissions reductions contest that provides financial rewards for the vessel crews that reduce the most amount of CO2, 2) use social comparisons as a way of showing vessel performance against the rest of the class, and 3) include an environmental notification system that informs operators about the total emissions from voyages.
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    Specialist and primary care physicians' views on barriers to adequate preparation of patients for renal replacement therapy: a qualitative study.
    (BMC Nephrol, 2015-03-28) Greer, Raquel C; Ameling, Jessica M; Cavanaugh, Kerri L; Jaar, Bernard G; Grubbs, Vanessa; Andrews, Carrie E; Ephraim, Patti; Powe, Neil R; Lewis, Julia; Umeukeje, Ebele; Gimenez, Luis; James, Sam; Boulware, L Ebony
    BACKGROUND: Early preparation for renal replacement therapy (RRT) is recommended for patients with advanced chronic kidney disease (CKD), yet many patients initiate RRT urgently and/or are inadequately prepared. METHODS: We conducted audio-recorded, qualitative, directed telephone interviews of nephrology health care providers (n = 10, nephrologists, physician assistants, and nurses) and primary care physicians (PCPs, n = 4) to identify modifiable challenges to optimal RRT preparation to inform future interventions. We recruited providers from public safety-net hospital-based and community-based nephrology and primary care practices. We asked providers open-ended questions to assess their perceived challenges and their views on the role of PCPs and nephrologist-PCP collaboration in patients' RRT preparation. Two independent and trained abstractors coded transcribed audio-recorded interviews and identified major themes. RESULTS: Nephrology providers identified several factors contributing to patients' suboptimal RRT preparation, including health system resources (e.g., limited time for preparation, referral process delays, and poorly integrated nephrology and primary care), provider skills (e.g., their difficulty explaining CKD to patients), and patient attitudes and cultural differences (e.g., their poor understanding and acceptance of their CKD and its treatment options, their low perceived urgency for RRT preparation; their negative perceptions about RRT, lack of trust, or language differences). PCPs desired more involvement in preparation to ensure RRT transitions could be as "smooth as possible", including providing patients with emotional support, helping patients weigh RRT options, and affirming nephrologist recommendations. Both nephrology providers and PCPs desired improved collaboration, including better information exchange and delineation of roles during the RRT preparation process. CONCLUSIONS: Nephrology and primary care providers identified health system resources, provider skills, and patient attitudes and cultural differences as challenges to patients' optimal RRT preparation. Interventions to improve these factors may improve patients' preparation and initiation of optimal RRTs.