Background: Collar-related pressure ulcers (CRPU) are a problem in trauma patients with a suspicion of cervical cord injury patients. Indentation marks (IM), skin temperature (Tsk) and comfort could play a role in the development of CRPU. Two comparable cervical collars are the Stifneck® and Philadelphia®. However, the differences between them remain unclear. Aim: To determine and compare occurrence and severity of IM, Tsk and comfort of the Stifneck® and Philadelphia® in immobilized healthy adults. Methods: This single-blinded randomized controlled trial compared two groups of immobilized participants in supine position for 20 min. Results: All participants (n = 60) generated IM in at least one location in the observed area. Total occurrence was higher in the Stifneck®-group (n = 95 versus n = 69; p = .002). Tsk increased significantly with 1.0 °C in the Stifneck®-group and 1.3 °C in the Philadelphia®-group (p = .024). Comfort was rated 3 on a scale of 5 (p = .506). Conclusion: The occurrence of IM in both groups was high. In comparison to the Stifneck®, fewer and less severe IM were observed from the Philadelphia®. The Tsk increased significantly with both collars; however, no clinical difference in increase of Tsk between them was found. The results emphasize the need for a better design of cervical collars regarding CRPU.
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Thermal comfort is determined by the combined effect of the six thermal comfort parameters: temperature, air moisture content, thermal radiation, air relative velocity, personal activity and clothing level as formulated by Fanger through his double heat balance equations. In conventional air conditioning systems, air temperature is the parameter that is normally controlled whilst others are assumed to have values within the specified ranges at the design stage. In Fanger’s double heat balance equation, thermal radiation factor appears as the mean radiant temperature (MRT), however, its impact on thermal comfort is often ignored. This paper discusses the impacts of the thermal radiation field which takes the forms of mean radiant temperature and radiation asymmetry on thermal comfort, building energy consumption and air-conditioning control. Several conditions and applications in which the effects of mean radiant temperature and radiation asymmetry cannot be ignored are discussed. Several misinterpretations that arise from the formula relating mean radiant temperature and the operative temperature are highlighted, coupled with a discussion on the lack of reliable and affordable devices that measure this parameter. The usefulness of the concept of the operative temperature as a measure of combined effect of mean radiant and air temperatures on occupant’s thermal comfort is critically questioned, especially in relation to the control strategy based on this derived parameter. Examples of systems which deliver comfort using thermal radiation are presented. Finally, the paper presents various options that need to be considered in the efforts to mitigate the impacts of the thermal radiant field on the occupants’ thermal comfort and building energy consumption.
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Synthetic ultra-black (UB) materials, which demonstrate exceptionally high absorbance (>99%) of visible light incident on their surface, are currently used as coatings in photovoltaic cells and numerous other applications. Most commercially available UB coatings are based on an array of carbon nanotubes, which are produced at relatively high temperature and result in numerous by-products. In addition, UB nanotube coatings require harsh application conditions and are very susceptible to abrasion. As a result, these coatings are currently obtained using a manufacturing process with relatively high costs, high energy consumption and low sustainability. Interestingly, an UB coating based on a biologically derived pigment could provide a cheaper and more sustainable alternative. Specifically, GLO Biotics proposes to create UB pigment by taking a bio-mimetic approach and replicate structures found in UB deep-sea fish. A recent study[1] has actually shown that specific fish have melanosomes in their skin with particular dimensions that allow absorption of up to 99.9% of incident light. In addition to this, recent advances in bacterial engineering have demonstrated that it is possible to create bacteria-derived melanin particles with very similar dimensions to the melanosomes in aforementioned fish. During this project, the consortium partners will combine both scientific observations in an attempt to provide the proof-of-concept for developing an ultra-black coating using bacteria-derived melanin particles as bio-based, sustainable pigment. For this, Zuyd University of Applied Sciences (Zuyd) and Maastricht University (UM) collaborate with GLO Biotics in the development of the innovative ‘BLACKTERIA’ UB coating technology. The partners will attempt at engineering an E. coli expression system and adapt its growth in order to produce melanin particles of desired dimensions. In addition, UM will utilize their expertise in industrial coating research to provide input for experimental set-up and the development of a desired UB coating using the bacteria-derived melanin particles as pigment.
