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Latent heat thermal energy storage (LHTES) uses phase change materials (PCMs) to store and release heat, and can effectively address the mismatch between energy supply and demand. However, it suffers from low thermal conductivity and the leakage problem. One of the solutions is integrating porous supports and PCMs to fabricate shape-stabilized phase change materials (ss-PCMs). The phase change heat transfer in porous ss-PCMs is of fundamental importance for determining thermalfluidic behaviours and evaluating LHTES system performance. This paper reviews the Highlights: 1. The recent advances in experimental and numerical investigations on phase change heat transfer in porous ss-PCMs are reviewed. 2. Paraffin and metal foams are the mostly used PCM and porous support respectively in the experimental studies. 3. Compared to REV-scale simulation, the pore-scale simulation can provide extra flow and heat transfer characteristics in pores. 4. There exists a research gap between phase change heat transfer and material preparation.

Additive manufacturing (AM) can obtain not only customized external shape but also porous internal structure for scaffolds, both of which are of great importance for repairing large segmental bone defects. The scaffold fabrication process generally involves scaffold design, AM, and post-treatments. Thus, this article firstly reviews the state-of-the-art of scaffold design, including computer-aided design, reverse modeling, topology optimization, and mathematical modeling. In addition, the current characteristics of several typical AM techniques, including selective laser sintering, fused deposition modeling (FDM), and electron beam melting (EBM), especially their advantages and limitations are presented. In particular, selective laser sintering is able to obtain scaffolds with nanoscale grains, due to its high heating rate and a short holding time. However, this character usually results in insufficient densification. FDM can fabricate scaffolds with a relative high accuracy of pore structure but with a relative low mechanical strength. EBM with a high beam-material coupling efficiency can process high melting point metals, but it exhibits a low-resolution and poor surface quality. Furthermore, the common post-treatments, with main focus on heat and surface treatments, which are applied to improve the comprehensive performance are also discussed. Finally, this review also discusses the future directions for AM scaffolds for bone tissue engineering.

BackgroundThis study was conducted to ascertain the feasibility of using rapid oral fluid testing as an alternative HIV testing method in China.MethodThis is a mixed-method study among men who have sex with men (MSM), female sex workers (FSW) and VCT clients, conducted in 4 cities in Shandong Province. A pre-tested questionnaire was administered to 1137 participants through face-to-face interview to assess demographic characteristics, HIV testing histories and willingness to accept rapid oral fluid testing. VCT clients were provided with the saliva test kits for a screening test and errors in operation were recorded. Testing results were compared between oral and blood testing. Short feedback questionnaire was administered to 200 FSW who had undergone oral testing.ResultsThe rate of willingness to take oral-fluid HIV testing among MSM, FSW and VCT clients was 72.8%, 72.1% and 67.4% respectively. Common errors recorded during test kit operation by the 229 VCT clients included: unpreparedness, wrong swab sampling, wrong dilution, wrong testing and inability to read test results. Advantages of oral testing listed by participants included: less intrusive, painlessness, easy self- testing and privacy. Disadvantages included perceived unreliable results (55.5%) and not nationally recognised (9%). Comparison of saliva and the blood testing results recorded a consistency rate of 0.970 (χ2 = 153.348, P < 0.001), implying an excellent consistency.ConclusionIntroduction of oral rapid fluid testing as an alternative HIV testing method in China is highly feasible but with some challenges including low recognition and operation errors.