1,870 research outputs found

    Effect of entropy on the dynamics of supercooled liquids: New results from high pressure data

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    We show that for arbitrary thermodynamic conditions, master curves of the entropy are obtained by expressing S(T,V) as a function of TV^g_G, where T is temperature, V specific volume, and g_G the thermodynamic Gruneisen parameter. A similar scaling is known for structural relaxation times,tau = f(TV^g); however, we find g_G < g. We show herein that this inequality reflects contributions to S(T,V) from processes, such as vibrations and secondary relaxations, that do not directly influence the supercooled dynamics. An approximate method is proposed to remove these contributions, S_0, yielding the relationship tau = f(S-S_0).Comment: 10 pages 7 figure

    Quality of care assessment for people with multimorbidity.

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    Multimorbidity, the simultaneous presence of multiple health conditions in an individual, is an increasingly common phenomenon globally. The systematic assessment of the quality of care delivered to people with multimorbidity will be key to informing the organization of services for meeting their complex needs. Yet, current assessments tend to focus on single conditions and do not capture the complex processes that are required for providing care for people with multimorbidity. We conducted a scoping review on quality of care and multimorbidity in selected databases in June 2018 and identified 87 documents as eligible for review, predominantly original research and reviews from North America, Europe and Australasia and mostly frequently related to primary care settings. We synthesized data qualitatively in terms of perceived challenges, evidence and proposed metrics. Findings reveal that the association between quality of care and multimorbidity is complex and depends on the conditions involved (quality appears to be higher for those with concordant conditions, and lower in the presence of discordant conditions) and the approach used for measuring quality (quality appears to be higher in people with multimorbidity when measured using condition/drug-specific process or intermediate outcome indicators, and worse when using patient-centred reports of experiences of care). People with discordant multimorbidity may be disadvantaged by current approaches to quality assessment, particularly when they are linked to financial incentives. A better understanding of models of care that best meet the needs of this group is needed for developing appropriate quality assessment frameworks. Capturing patient preferences and values and incorporate patients' voices in the form of patient-reported experiences and outcomes of care will be critical towards the achievement of high-performing health systems that are responsive to the needs of people with multimorbidity

    Quantum walks can find a marked element on any graph

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    We solve an open problem by constructing quantum walks that not only detect but also find marked vertices in a graph. In the case when the marked set MM consists of a single vertex, the number of steps of the quantum walk is quadratically smaller than the classical hitting time HT(P,M)HT(P,M) of any reversible random walk PP on the graph. In the case of multiple marked elements, the number of steps is given in terms of a related quantity HT+(P,M)HT^+(\mathit{P,M}) which we call extended hitting time. Our approach is new, simpler and more general than previous ones. We introduce a notion of interpolation between the random walk PP and the absorbing walk PP', whose marked states are absorbing. Then our quantum walk is simply the quantum analogue of this interpolation. Contrary to previous approaches, our results remain valid when the random walk PP is not state-transitive. We also provide algorithms in the cases when only approximations or bounds on parameters pMp_M (the probability of picking a marked vertex from the stationary distribution) and HT+(P,M)HT^+(\mathit{P,M}) are known.Comment: 50 page

    Use of conventional and alternative treatment strategies for a case of low back pain in a F/A-18 aviator

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    BACKGROUND: Low back pain can diminish jet pilot concentration and function during flight and be severe enough to ground pilots or cause decreased flying time. The objective of this case report is to present an example of the integration of chiropractic care with conventional treatments for the management of low back pain in a F/A-18 aviator. CASE PRESENTATION: The patient had insidious severe low back pain without radiation or neurological deficit, resulting in 24 hours of hospitalization. Spinal degeneration was discovered upon imaging. Four months later, it still took up to 10 minutes for him to get out of bed and several minutes to exit the jet due to stiffness and pain. He had discontinued his regular Marine Corps fitness training due to pain avoidance. Pain severity ranged from 1.5–7.1 cm on a visual analog scale. His Roland Morris Disability Questionnaire score was 5 out of 24. The pilot's pain was managed with the coordinated efforts of the flight surgeon, physiatrist, physical therapist, and doctor of chiropractic. Following this regimen he had no pain and no functional disability; he was able to fly multiple training missions per week and exercise to Marine Corps standards. CONCLUSION: A course of care integrating flight medicine, chiropractic, physical therapy, and physiatry appeared to alleviate pain and restore function to this F/A-18 aviator with low back pain

    Aspects of the political economy of development and synthetic biology

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    What implications might synthetic biology’s potential as a wholly new method of production have for the world economy, particularly developing countries? Theories of political economy predict that synthetic biology can shift terms of trade and displace producers in developing countries. Governments, however, retain the ability to mitigate negative changes through social safety nets and to foster adaptation to some changes through research, education and investment. We consider the effects the synthetic production of otherwise naturally derived molecules are likely to have on trade and investment, particularly in developing countries. Both rubber in Malaysia and indigo dyes in India provide historical examples of natural molecules that faced market dislocations from synthetic competitors. Natural rubber was able to maintain significant market share, while natural indigo vanished from world markets. These cases demonstrate the two extremes of the impact synthetic biology might have on naturally derived products. If developing countries can cushion the pain of technological changes by providing producers support as they retool or exit, the harmful effects of synthetic biology can be mitigated while its benefits can still be captured

    The translation, validity and reliability of the German version of the Fremantle Back Awareness Questionnaire

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    Background: The Fremantle Back Awareness Questionnaire (FreBAQ) claims to assess disrupted self-perception of the back. The aim of this study was to develop a German version of the Fre-BAQ (FreBAQ-G) and assess its test-retest reliability, its known-groups validity and its convergent validity with another purported measure of back perception. Methods: The FreBaQ-G was translated following international guidelines for the transcultural adaptation of questionnaires. Thirty-five patients with non-specific CLBP and 48 healthy participants were recruited. Assessor one administered the FreBAQ-G to each patient with CLBP on two separate days to quantify intra-observer reliability. Assessor two administered the FreBaQ-G to each patient on day 1. The scores were compared to those obtained by assessor one on day 1 to assess inter-observer reliability. Known-groups validity was quantified by comparing the FreBAQ-G score between patients and healthy controls. To assess convergent validity, patient\u27s FreBAQ-G scores were correlated to their two-point discrimination (TPD) scores. Results: Intra- and Inter-observer reliability were both moderate with ICC3.1 = 0.88 (95%CI: 0.77 to 0.94) and 0.89 (95%CI: 0.79 to 0.94), respectively. Intra- and inter-observer limits of agreement (LoA) were 6.2 (95%CI: 5.0±8.1) and 6.0 (4.8±7.8), respectively. The adjusted mean difference between patients and controls was 5.4 (95%CI: 3.0 to 7.8, p\u3c0.01). Patient\u27s FreBAQ-G scores were not associated with TPD thresholds (Pearson\u27s r = -0.05, p = 0.79). Conclusions: The FreBAQ-G demonstrated a degree of reliability and known-groups validity. Interpretation of patient level data should be performed with caution because the LoA were substantial. It did not demonstrate convergent validity against TPD. Floor effects of some items of the FreBAQ-G may have influenced the validity and reliability results. The clinimetric properties of the FreBAQ-G require further investigation as a simple measure of disrupted self-perception of the back before firm recommendations on its use can be made
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