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During the mid-Pliocene warm period (mPWP; 3.264–3.025 Ma), atmospheric CO 2 concentrations were approximately 400 ppm, and the Antarctic Ice Sheet was substantially reduced compared to today. Antarctica is surrounded by the Southern Ocean, which plays a crucial role in the global oceanic circulation and climate regulation. Using results from the Pliocene Model Intercomparison Project (PlioMIP2), we investigate Southern Ocean conditions during the mPWP with respect to the pre-industrial period. We find that the mean sea surface temperature (SST) warming in the Southern Ocean is 2.8 °C, while global mean SST warming is 2.4 °C. The enhanced warming is strongly tied to a dramatic decrease in sea ice cover over the mPWP Southern Ocean. We also see a freshening of the ocean (sub)surface, driven by an increase in precipitation over the Southern Ocean and Antarctica. The warmer and fresher surface leads to a highly stratified Southern Ocean that can be related to weakening of the deep abyssal overturning circulation. Sensitivity simulations show that the decrease in sea ice cover and enhanced warming is largely a consequence of the reduction in the Antarctic Ice Sheet. In addition, the mPWP geographic boundary conditions are responsible for approximately half of the increase in mPWP SST warming, sea ice loss, precipitation, and stratification increase over the Southern Ocean. From these results, we conclude that a strongly reduced Antarctic Ice Sheet during the mPWP has a substantial influence on the state of the Southern Ocean and exacerbates the changes that are induced by a higher CO 2 concentration alone. This is relevant for the long-term future of the Southern Ocean, as we expect melting of the western Antarctic Ice Sheet in the future, an effect that is not currently taken into account in future projections by Coupled Model Intercomparison Project (CMIP) ensembles. [ABSTRACT FROM AUTHOR]

During the mid-Pliocene (3.264-3.025 Ma), atmospheric CO2 concentrations were approximately 400 ppm and the Antarctic ice sheet was substantially reduced compared to today. Antarctica is surrounded by the Southern Ocean, which plays a crucial role in the global oceanic circulation and climate regulation. Using results from the Pliocene Model Intercomparison Project (PlioMIP2), we investigate Southern Ocean conditions during the mid-Pliocene with respect to the pre-industrial period. We find that the mean sea surface temperature (SST) warming in the Southern Ocean is 2.8°C, while global mean SST warming is 2.4°C. The enhanced warming is strongly tied to a dramatic decrease in sea-ice cover over the mid-Pliocene Southern Ocean. We also see a freshening of the ocean (sub)surface, driven by an increase in precipitation over the Southern Ocean and Antarctica. The warmer and fresher surface leads to a highly stratified Southern Ocean, that can be related to weakening of the deep abyssal overturning circulation. Sensitivity simulations show that the decrease in sea-ice cover and enhanced warming is largely a consequence of the reduction of the Antarctic ice sheet. In addition, the mid-Pliocene geographic boundary conditions are responsible for approximately half of the increase in mid-Pliocene SST warming, sea ice loss, precipitation and stratification increase over the Southern Ocean. From these results, we conclude that a strongly reduced Antarctic Ice Sheet during the mid- Pliocene has a substantial influence on the state of the mid-Pliocene Southern Ocean and exacerbates the changes that are induced by a higher CO2 concentration alone. This is relevant for the long-term future of the Southern Ocean, as we expect melting of the western Antarctic ice sheet in the future, an effect that is not currently taken into account in future projections by CMIP ensembles. [ABSTRACT FROM AUTHOR]

Global reconstructions of Pliocene climate provide important insights into how the climate system operates under elevated temperatures and atmospheric CO2 levels. These reconstructions have been used extensively in paleoclimate modeling experiments for comparison to simulated conditions, and as boundary conditions. Most previous work focused on the Late Pliocene interval known as the mid PiacenzianWarm Period (mPWP), the interval originally identified by the U.S. Geological Survey Pliocene Research, Interpretation and Synoptic Mapping Project (PRISM) as the PRISM interval or Mid Pliocene Warm Period. The term Mid Pliocene Warm Period is a misnomer due to changes to the geological time scale, and its use should be discontinued. The Pliocene Model Intercomparison Project (PlioMIP), now in its third phase, is expanding to include a focus on the Early Pliocene (Zanclean). PlioMIP3 experimentswill allow comparison of environmental and climatic conditions before and after closure of the Central American Seaway (CAS). PlioMIP3 used the annual insolation pattern at the top of the atmosphere to determine time slices in the Zanclean that have orbital configurations that are most similar to modern. Two have been selected by PlioMIP and adopted by PRISM for inclusion in future studies: PRISM5.1 (4.474 Ma) and PRISM5.2 (4.870 Ma). Here we establish the stratigraphic framework for these Early Pliocene time slices and furnish information to help locate these intervals in proxy records of paleoenvironmental data using oxygen isotope stratigraphy, paleomagnetic stratigraphy, biostratigraphy, and biochronology (calibrated planktic foraminifer and calcareous nannofossil events). [ABSTRACT FROM AUTHOR]

* OBJECTIVE: To describe the variation in outcomes and number of visits before and after implementing a care guideline for total knee arthroplasty (TKA) rehabilitation. * DESIGN: Nonrandomized intervention study. * METHODS: We compared 2558 patients with TKA who received care that was not standardized (non--care guideline [NCG] group) to 9797 patients with TKA who received care according to the care guideline (CG). We fit 2 Bayesian hierarchical linear regression models using the Knee Outcome Survey -- Activities of Daily Living (KOS-ADL) change score and number of physical therapy (PT) visits as the response variables, controlling for relevant predictor variables. We also compared the ratio of the standard deviations of the KOS-ADL change scores and the number of PT visits within and between clinics. * RESULTS: The overall estimated mean improvement in KOS-ADL change score was 23.0 points (95% confidence interval [CI]: 20.3, 25.7) in the NCG group and 28.7 points (95% CI: 27.5, 29.7) in the CG group; the mean difference was 5.6 (2.7-8.6). Mean KOS-ADL change scores were higher in the CG group than the NCG group in every clinic, although only 8 clinics improved significantly. The number of PT visits did not change meaningfully (NCG: mean, 10.7 [95% CI: 9.9, 11.5]; CG: mean, 10.5 [95% CI: 9.9, 10.9]). Variation in KOS-ADL change score decreased by 4% within clinics (CG-NCG ratio: 0.96 [95% CI: 0.93, 0.99]) and 63% between clinics (CG-NCG ratio: 0.37 [95% CI: 0.21, 0.62]). Variation in number of visits decreased by 7% within clinics (CG-NCG ratio: 0.93 [95% CI: 0.90, 0.96]) and 19% between clinics (CG-NCG ratio: 0.81 [95% CI: 0.39, 1.49]). * CONCLUSION: Implementing a care guideline for TKA rehabilitation may improve outcomes and reduce unwarranted variation in practice within clinics and especially between clinics within a large health care system. [ABSTRACT FROM AUTHOR]

* OBJECTIVE: To describe the application and examine the influence of a continuous quality improvement intervention, which had a goal of standardizing care to reduce the proportion of patients who do not have a meaningful improvement in patient-reported outcomes following total knee arthroplasty (TKA). * DESIGN: Continuous quality improvement. * METHODS: A physical therapy (PT) care guideline was initiated in 2013 for patients following TKA. The Knee Outcome Survey -- Activities of Daily Living (KOS-ADL) was measured at every visit, and scores were extracted from a clinical outcomes database to calculate the proportion of patients who did not achieve a minimal clinically important difference. Based on logistic regression analysis, we compared the proportion of patients who did not progress on the KOS-ADL in a non--care guideline group (2008-2012) to a care guideline (CG) group (2014-2019). * RESULTS: This study included 12 355 patients (aged 18-92 years) following TKA incurring at least 3 PT visits from 2008 to 2019. The percentage of patients who did not progress in the non--care guideline group was 25.8% and in the care guideline group 14.3% (P<0.001). The relationship between care guideline adherence and lack of progression on the KOS-ADL was statistically significant, X² (df = 1) = 148.7, P<.001. * CONCLUSION: The percentage of patients who did not achieve meaningful progress on the KOSADL declined significantly in the 6 years after implementing a TKA care guideline without an increase in the number of clinical visits. The standardized care guideline was associated with meaningful improvements for patients following TKA when applied in conjunction with PT access to outcome data, feedback through audits, performance goals, and financial incentives. [ABSTRACT FROM AUTHOR]

Understanding the dominant climate forcings in the Pliocene is crucial to assessing the usefulness of the Pliocene as an analogue for our warmer future. Here we implement a novel, yet simple linear factorisation method to assess the relative influence of CO2 forcing in seven models of the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2) ensemble. Outputs are termed "FCO2" and show the fraction of Pliocene climate change driven by CO2. The accuracy of the FCO2 method is first assessed through comparison to an energy balance analysis previously used to assess drivers of surface air temperature in the PlioMIP1 ensemble. After this assessment, the FCO2 method is applied to achieve an understanding of the drivers of Pliocene sea surface temperature and precipitation for the first time. CO2 is found to be the most important forcing in the ensemble for Pliocene surface air temperature (global mean FCO2 = 0.56), sea surface temperature (global mean FCO2 = 0.56) and precipitation (global mean FCO2 = 0.51). The range between individual models is found to be consistent between these three climate variables, and the models generally show good agreement on the sign of the most important forcing. Our results provide the most spatially complete view of the drivers of Pliocene climate to date, and have implications for both data-model comparison and the use of the Pliocene as an analogue for the future. That CO2 is found to be the most important forcing reinforces that the Pliocene is a good palaeoclimate analogue, but the significant effect of non-CO2 forcing at regional scale reminds us that it is not perfect, and this must not be overlooked. This comparison is further complicated when considering the Pliocene as a state in quasi-equilibrium with CO2 forcing compared to the transient warming being experienced at present. [ABSTRACT FROM AUTHOR]