Improper operating temperature will degrade the performances of electronic components, Li-ion batteries and photovoltaic (PV) cells, which calls for a good thermal management system. In this paper, specific attention is paid to the thermal management systems based on the phase change materials (PCMs). Performances of the PCM-based thermal management systems for each kind of these three devices along with the type of PCM used, thermal properties of that kind of PCM, like phase change temperature, enthalpy of phase change and thermal conductivity are discussed. Discussion in detail on techniques to improve the thermal conductivity of PCMs is made because of its crucial influence. Advanced-structure heatsinks with multi-layer PCMs and hybrid passive heatsinlcs combined with active cooling are also introduced. The PCM-based thermal management system is powerful in ensuring electronic devices, Li-ion batteries and photovoltaic cells working safely and efficiently. (C) 2014 Elsevier Ltd. All rights reserved.

Objective: A systematic review of randomized controlled trials was conducted to examine the efficacy of fibrin sealants for the reduction of postoperative blood loss and allogeneic red blood cell transfusion in total knee arthroplasty (TKA). Methods: Studies published through May 2013 were identified from PubMed, Embase, the Cochrane library, ScienceDirect, and other databases. Two independent reviewers assessed the quality of methodology using the Grade of Recommendations Assessment, Development and Evaluation approach and extracted data from literature. The mean difference (MD) of blood loss, hemoglobin loss, and risk ratios (RR) of transfusion rate and adverse events in the fibrin-treated and placebo groups were pooled throughout the study. The relevant data were analyzed using Stata 11.0 software. Results: Eight studies were included in the review, with a total sample size of 558 patients. The drainage blood loss [MD = -354.02 mL, 95% confidence interval (CI) (-500.87 to -207.18); P < 0.05], reduction in calculated total blood loss [MD - -402.12, 95% CI (-599.16 to -205.08); P < 0.05], hemoglobin loss [MD - -0.86 g/dL, 95% CI (-1.10 g/dL to -0.61 g/dL); P < 0.05], and transfusion rate [RR -0.62, 95% CI (0.45-0.86); P < 0.05] were all significantly reduced following treatment with fibrin sealants. There were no significant differences in the incidence of adverse events [RR -0.69, 95% CI (0.32-1.59); P > 0.05] among the study groups. Conclusions: The results of the present meta-analysis suggest that fibrin sealants for patients undergoing TKA may reduce blood loss and maintain higher hemoglobin levels, particularly when fibrin sealants are used at higher dosage. Furthermore, fibrin sealants do not increase the risk of postoperative deep vein thrombosis, superficial infection, pulmonary embolism, and hematoma. Further evaluation is required to confirm our findings before fibrin sealants can be used in patients undergoing TKA. Level of evidence: II. (C) 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.