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Manganese(III/IV) oxide is a promising pseudocapacitive material for supercapacitor electrodes due to favorable attributes such as its chemical resilience, high earth abundance and low specific cost. Herein, the morphological, compositional and electrochemical characteristics of co‐precipitated manganese(III/IV) oxide products, each described by the general formula NaxKyMnOz, are investigated to establish how these properties are influenced by synthesis conditions. NaxKyMnOz growths in low‐temperature (<100 °C) basic and acidic environments are shown to promote the formation of turbostratic birnessite and cryptomelane phases, respectively, with the latter polymorph containing a relatively low concentration of interstitial Na+ and K+ cations. It is demonstrated that K+ pre‐insertion during synthesis yields lower initial charge‐transfer resistances than equivalent Na+ intercalation, and that this parameter correlates strongly with storage performance. Accordingly, Na‐mediated storage initially delivers inferior specific capacitances and Coulombic efficiencies than K‐based mechanisms, but K+ intercalation/deintercalation causes faster capacitance decay during prolonged galvanostatic cycling. Furthermore, whilst crystallographic phase is shown to have a weaker effect on NaxKyMnOz storage properties than the choice of intercalating guest cations, cryptomelane electrodes are more susceptible to cycling‐induced capacitance and efficiency losses than their birnessite counterparts. In combination, these insights provide an instructive foundation for the optimization of NaxKyMnOz in high‐power storage applications. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate modern surgical outcomes in patients with stable heart failure undergoing elective major noncardiac surgery and to compare the experience of patients with heart failure who have reduced [...]

This article presents a novel method for accelerated wear of squeegees used in screen printing and describes the development of mechanical tests which allow more in-depth measurement of squeegee properties. In this study, squeegees were abraded on the screen press so that they could be used for subsequent print tests to evaluate the effect of wear on the printed product. Squeegee wear was found to vary between different squeegee types and caused increases in ink transfer and wider printed features. In production this will lead to greater ink consumption, cost per unit and a likelihood of product failure. This also has consequences for the production of functional layers, etc., used in the construction of printed electronics. While more wear generally gave greater increases in ink deposition, the effect of wear differed, depending on the squeegee. There was a correlation between the angle of the squeegee wear and ink film thickness from a worn squeegee. An ability to resist flexing gave a high wear angle and presented a sharper edge at the squeegee/screen interface thus mitigating the effect of wear. There was also a good correlation between resistance to flexing and ink film thickness for unworn squeegees, which was more effective than a comparison based on Shore A hardness. Squeegee indentation at different force levels gave more information than a standard Shore A hardness test and the apparatus used was able to reliably measure reductions in surface hardness due to solvent absorption. Increases in ink deposition gave lower resistance in printed silver lines; however, the correlation between the amount of ink deposited and the resistance, remained the same for all levels of wear, suggesting that the wear regime designed for this study did not induce detrimental print defects such as line breakages. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate modern surgical outcomes in patients with stable heart failure undergoing elective major noncardiac surgery and to compare the experience of patients with heart failure who have reduced vs preserved left ventricular ejection fraction (EF). PATIENTS AND METHODS: We retrospectively studied 557 consecutive patients with heart failure (192 EF £40% and 365 EF >40%) and 10,583 controls who underwent systematic evaluation by hospitalists in a preoperative clinic before having major elective noncardiac surgery between January 1, 2003, and March 31, 2006. We examined outcomes in the entire cohort and in propensity-matched case-control groups. RESULTS: Unadjusted 1-month postoperative mortality in patients with both types of heart failure vs controls was 1.3% vs 0.4% (P=.009), but this difference was not significant in propensity-matched groups (P=.09). Unadjusted differences in mean hospital length of stay among heart failure patients vs controls (5.7 vs 4.3 days; P<.001) and 1-month readmission (17.8% vs 8.5%; P<.001) were also markedly attenuated in propensity-matched groups. Crude 1-year hazard ratios for mortality were 1.71 (95% confidence interval [CI], 1.5-2.0) for both types of heart failure, 2.1 (95% CI, 1.7-2.6) in patients with heart failure who had EF £40%, and 1.4 (95% CI, 1.2-1.8) in those who had EF >40% (P<.01 for all 3 comparisons); however, the differences were not significant in propensity-matched groups (P=.43). CONCLUSION: Patients with clinically stable heart failure did not have high perioperative mortality rates in association with elective major noncardiac surgery, but they were more likely than patients without heart failure to have longer hospital stays, were more likely to require hospital readmission, and had a substantial long-term mortality rate. [ABSTRACT FROM AUTHOR]

Background: Discharge planning is a routine feature of health systems in many countries. The aim of discharge planning is to reduce hospital length of stay and unplanned readmission to hospital, and improve the co-ordination of services following discharge from hospital., Objectives: To determine the effectiveness of planning the discharge of patients moving from hospital., Search Strategy: We updated the review using the Cochrane EPOC Group Trials Register, MEDLINE, EMBASE and the Social Science Citation Index (last searched in March 2009)., Selection Criteria: Randomised controlled trials (RCTs) that compared an individualised discharge plan with routine discharge care that was not tailored to the individual patient. Participants were hospital inpatients., Data Collection and Analysis: Two authors independently undertook data analysis and quality assessment using a predesigned data extraction sheet. Studies are grouped according to patient group (elderly medical patients, surgical patients and those with a mix of conditions) and by outcome., Main Results: Twenty-one RCTs (7234 patients) are included; ten of these were identified in this update. Fourteen trials recruited patients with a medical condition (4509 patients), four recruited patients with a mix of medical and surgical conditions (2225 patients), one recruited patients from a psychiatric hospital (343 patients), one from both a psychiatric hospital and from a general hospital (97 patients), and the final trial recruited patients admitted to hospital following a fall (60 patients). Hospital length of stay and readmissions to hospital were significantly reduced for patients allocated to discharge planning (mean difference length of stay -0.91, 95% CI -1.55 to -0.27, 10 trials; readmission rates RR 0.85, 95% CI 0.74 to 0.97, 11 trials). For elderly patients with a medical condition (usually heart failure) there was insufficient evidence for a difference in mortality (RR 1.04, 95% CI 0.74 to 1.46, four trials) or being discharged from hospital to home (RR 1.03, 95% CI 0.93 to 1.14, two trials). This was also the case for trials recruiting patients recovering from surgery and a mix of medical and surgical conditions. In three trials patients allocated to discharge planning reported increased satisfaction. There was little evidence on overall healthcare costs., Authors' Conclusions: The evidence suggests that a structured discharge plan tailored to the individual patient probably brings about small reductions in hospital length of stay and readmission rates for older people admitted to hospital with a medical condition. The impact of discharge planning on mortality, health outcomes and cost remains uncertain.