801 research outputs found

    Spatial Contours of Potential Biomass Crop Production: An Examination of Variations by U.S. Region

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    The recent and projected status of energy production and consumption in the United States, resulting in substantial dependencies upon foreign oil, has continued to provide pressure on domestic energy security. All told, bio-energy systems, and biomass crop production in particular, will be important elements of national security, economic vitality, and public policy. Using biomass crop estimates based upon models developed at the Oak Ridge National Laboratory and the Department of Energy (DOE) National Renewable Energy Laboratory, we identify potential biomass crop production zones using spatial analysis methods. The Midwest and the South are, by far, the largest regions of potential production. Once potential biomass crop yield is made proportional to estimated land and production costs, the South’s optimal crop zones fall along the Gulf Coast and Atlantic Seaboard, whereas in the Midwest, they are largely in non-metropolitan localities. The implications of these spatial contours for energy policy for alternative biomass crop production are discussed

    Differential Burden of Musculoskeletal Pain in Blacks and Whites at the Time of Total Joint Replacement Surgery

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    Introduction: The existence of racial disparities in total knee (TKR) and hip (THR) replacement outcomes is well established. The role of musculoskeletal co-morbidities among black and white TKR patients at the time of surgery were investigated in a prospective cohort enrolled in the FORCE-TJR consortium of 131 surgeons in 22 US states. Materials & methods: Descriptive analyses were performed on 3,306 TKR and 2,439 THR patients. Data included sociodemographic factors (age, sex, race), BMI, comorbid conditions using the modified Charlson comorbidity scores, burden of musculoskeletal disease using the Knee/Hip injury and Osteoarthritis Outcome Score (KOOS/HOOS) in both knees and hips, emotional health based on the Short Form 36 (SF-36) Mental Component Score (MCS) and physical function based on the Physical Component Score (SF-36 PCS). Factors associated with pre-operative surgical joint pain and function were examined using multivariate stepwise linear regression models. Results: Compared to Whites, Blacks (143 hips and 201 knees) reported worse surgical joint pain (mean pain: 39.3 vs. 49.2 (hip); 43.4 vs. 53.2 (knee)), poorer surgical joint function (mean function: 38.9 vs. 45.7 (hip); 45.9 vs. 53.4 (knee)), poorer global function (mean PCS: 30.0 vs. 31.6 (hip); 31.3 vs. 33.1 (knee)), and more non-operative joints pain. (All p\u3c0.03). In adjusted multivariable models, differences at the time of surgery in surgical joint symptoms and global function were explained by differences in musculoskeletal pain in the hips, knees, and low back. Conclusion: Greater burden of musculoskeletal pain explains differences in pre-operative pain and function between Blacks and Whites and likely impacts rehabilitation and subsequent TJR outcomes

    Differential burden of musculoskeletal pain in African Americans and whites patients at the time of total joint replacement surgery

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    Objective: African Americans patients have greater operative joint pain and functional limitation at the time of total joint replacement (TJR) compared to white patients. We examined the factors associated with this apparent disparity. Methods: A consecutive sample of 5745 patients with advanced knee and hip osteoarthritis [who elected to undergo TJR in 2011-201] reported, preoperatively, medical comorbidities, operative and non-operative hip/ knee pain using Hip and Knee Disability and Osteoarthritis Outcome Scores (HOOS/KOOS), function using Short Form 36 Physical Component Score (PCS). Total burden of musculoskeletal pain was quantified as moderate/severe pain in non-operative hip and knee joints and lumbar back pain using Oswestry Disability Index (ODI). Associations among race, medical co-morbidites (modified Charlson), total musculoskeletal pain burden, operative joint pain, and functional limitations were examined using multivariable regression models. Results:Compared to Whites, African Americans (143 hips and 201 knees) reported worse surgical joint pain (mean pain: 39.3 vs. 49.2 [hip]; 43.4 vs. 53.2 [knee]), poorer surgical joint function (mean function: 38.9 vs. 45.7 [hip]; 45.9 vs. 53.4 [knee]), poorer global function (mean PCS: 30.0 vs. 31.6 [hip]; 31.3 vs. 33.1 [knee]), and more non-operative joints pain (p Conclusions: Greater burden of musculoskeletal pain explains differences in pre-operative pain and function between African American and white patients and likely impacts rehabilitation and subsequent TJR outcomes

    Greater Co-morbidity Burden is Associated with Greater Pain and Disability at Time of Total Knee Replacement Among African American Patients

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    Introduction: The existence of racial disparities in total joint replacement (TJR) care is well established based on Medicare and VA data.1,3 As compared to white patients, African American TJR patients have lower utilization rates, more pain, poorer function at the time of surgery, and higher post-operative complication rates.2,3 We analyzed a national prospective total knee replacement (TKR) cohort to further investigate patterns of medical and musculoskeletal co-morbidities among African American and white TKR patients. Methods: Descriptive analyses were performed on a national database (FORCE-TJR) of 3,313 TKR patients from 107 orthopedic surgeons. Data collected include patient sociodemographics (age, gender, race, education, insurance, household income, smoking status), modified Charlson co-morbidity scores, and pre-operative and post-operative pain and function scores (SF-36 PCS and MCS, WOMAC, KOOS/HOOS ADL score). To assess the total musculoskeletal pain burden, WOMAC pain scores were recorded for non-operative weight bearing joints as well as Oswestry low back pain scores. Multivariate models are in progress. Results: Preliminary descriptive analyses demonstrate a higher medical co-morbidity burden in African American TKR patients as compared to whites (COPD, DM, smoking), as well as worse baseline pain (mean WOMAC pain score = 43.46 vs. 52.92, p Conclusion: Preliminary results demonstrate significant differences in medical and musculoskeletal co-morbidities that correlate with poorer pain and function scores in African American patients at the time of TKR

    Managing the delivery of iconic football stadiums in England

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    The English football premier league has become the most popular sports league in the world; with ardent fans and audiences all over the world. The potential business opportunities that this growth holds have therefore attracted investors who are keen to buy shares in the clubs and sign up the best footballers that money can buy. Underpinning the growth in all of the premier league clubs is a desire to make a distinct statement of identity as part of a competitive strategy. One way to achieve this is through the design and construction of iconic football stadiums. This paper explores the specific project management challenges associated with delivery of iconic football stadiums in England and draws lessons for the management of similar iconic infrastructure projects. A study of project management best practice and some case studies shows that key issues which are common to these projects are centred on design management; choice of procurement route; client management; and stakeholder expectation management. These issues are not necessarily unique to the project management of iconic football stadiums but are amplified by the context of these projects. The emphasis on iconic status in a competitive market also means that stadium projects should be conceived and delivered in the context of other strategic projects which should be clearly understood by the project management team

    Feedback control architecture and the bacterial chemotaxis network.

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    PMCID: PMC3088647This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Bacteria move towards favourable and away from toxic environments by changing their swimming pattern. This response is regulated by the chemotaxis signalling pathway, which has an important feature: it uses feedback to 'reset' (adapt) the bacterial sensing ability, which allows the bacteria to sense a range of background environmental changes. The role of this feedback has been studied extensively in the simple chemotaxis pathway of Escherichia coli. However it has been recently found that the majority of bacteria have multiple chemotaxis homologues of the E. coli proteins, resulting in more complex pathways. In this paper we investigate the configuration and role of feedback in Rhodobacter sphaeroides, a bacterium containing multiple homologues of the chemotaxis proteins found in E. coli. Multiple proteins could produce different possible feedback configurations, each having different chemotactic performance qualities and levels of robustness to variations and uncertainties in biological parameters and to intracellular noise. We develop four models corresponding to different feedback configurations. Using a series of carefully designed experiments we discriminate between these models and invalidate three of them. When these models are examined in terms of robustness to noise and parametric uncertainties, we find that the non-invalidated model is superior to the others. Moreover, it has a 'cascade control' feedback architecture which is used extensively in engineering to improve system performance, including robustness. Given that the majority of bacteria are known to have multiple chemotaxis pathways, in this paper we show that some feedback architectures allow them to have better performance than others. In particular, cascade control may be an important feature in achieving robust functionality in more complex signalling pathways and in improving their performance
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