Separation of Doppler radar-based respiratory signatures

Respiration detection using microwave Doppler radar has attracted significant interest primarily due to its unobtrusive form of measurement. With less preparation in comparison with attaching physical sensors on the body or wearing special clothing, Doppler radar for respiration detection and monitoring is particularly useful for long-term monitoring applications such as sleep studies (i.e. sleep apnoea, SIDS). However, motion artefacts and interference from multiple sources limit the widespread use and the scope of potential applications of this technique. Utilising the recent advances in independent component analysis (ICA) and multiple antenna configuration schemes, this work investigates the feasibility of decomposing respiratory signatures into each subject from the Doppler-based measurements. Experimental results demonstrated that FastICA is capable of separating two distinct respiratory signatures from two subjects adjacent to each other even in the presence of apnoea. In each test scenario, the separated respiratory patterns correlate closely to the reference respiration strap readings. The effectiveness of FastICA in dealing with the mixed Doppler radar respiration signals confirms its applicability in healthcare applications, especially in long-term home-based monitoring as it usually involves at least two people in the same environment (i.e. two people sleeping next to each other). Further, the use of FastICA to separate involuntary movements such as the arm swing from the respiratory signatures of a single subject was explored in a multiple antenna environment. The separated respiratory signal indeed demonstrated a high correlation with the measurements made by a respiratory strap used currently in clinical settings.

A qualitative exploration of body image experiences of women progressing through pregnancy

BACKGROUND: Pregnancy provides an interesting challenge to body image theories in that the natural physiological changes push women further from the socioculturally prescribed thin ideal which these theories hinge upon. The impact that these significant physiological changes have on the woman's body image during pregnancy may depend on the extent to which they retain or revise the ideal. However, little is known about body image experiences during pregnancy. AIM: To provide a comprehensive exploration of the body image experiences of pregnant women. METHODS: Individual structured interviews were conducted with 19 currently pregnant women. Transcriptions were analysed using a thematic content analysis approach. FINDINGS: Themes extracted from the qualitative data included: (1) women's body image experiences during pregnancy were complex and changing, and shaped by the salience of specific body parts, the women's expectations for future changes to their body within the perinatal period, the functionality of the body, and their experience of maternity clothing, (2) women were able to negotiate the changes to their bodies as they recognised the functionality of the pregnant body, (3) women were surprised by the public nature of the pregnant body, (4) partner support and positive feedback about the pregnant body was highly valued, and (5) the importance of open communication around weight and body image in antenatal healthcare. DISCUSSION: Our findings highlight the need for the adaptation and expansion of existing body image theories to be used as a framework for women's experiences of pregnancy.

The effect of fibrous structural difference on thermal insulation properties of biological composites: silkworm cocoons

As a biological fibrous structure, silkworm cocoon provides multiple protective functionalities to safeguard the silk moth pupa’s metabolic activity. The mechanism of this protection could be adopted in clothing manufacture to provide more comfortable apparel. In this study, the thermal insulation properties of both domestic Bombyx mori (B. mori) and wild Antheraea pernyi (A. pernyi) cocoons were investigated under both warm and cold environmental conditions. Computational fluid dynamics models have been developed to simulate the heat transfer process through both types of cocoon wall structures. The simulation results show that the wild A. pernyi cocoon reduces the intensity of convection and heat flux between the environment and the cocoon interior and has higher wind resistance than its domestic counterpart. Compared with A. pernyi cocoon, the B. mori cocoon facilitates easy air transfer and decreases the temperature lag when the surrounding conditions are changed. The new knowledge has significant implications for developing biomimetic thermal functional materials.

Detection and analysis of human respiration using microwave Doppler radar

 Non-contact detection characteristic of Doppler radar provides an unobtrusive means of respiration detection and monitoring. This avoids additional preparations such as physical sensor attachment or special clothing. Furthermore, robustness of Doppler radar against environmental factors reduce environmental constraints and strengthens the possibility of employing Doppler radar as a practical biomedical devices in the future particularly in long term monitoring applications such as in sleep studies.

Assessing the validity of tympanic temperature to predict core temperature of firefighters in different environmental conditions

The present study examined the validity of tympanic temperature measurements as a predictor of core temperature on the fireground in different environmental conditions. Fiftyone volunteer firefighters participated in the study across four different conditions, the conditions consisted of; 1) passive (i.e., no intervention) cooling in cold ambient temperatures (0-6°C); 2) cooling (through water immersion) in cool ambient temperatures (10-12ºC); 3) cooling (through water immersion) in warm ambient temperatures (21.5°C); and, 4) passive cooling in warm ambient temperatures (22°C). Firefighters wore full structural personal protective clothing while performing common firefighting duties including search and rescue tasks for 20-40 minutes. There was no difference between core and tympanic temperature immediately post-exercise across any condition. However, for all conditions, tympanic temperature dropped significantly faster than core temperature from 0 minutes, and remained significantly lower (p < 0.05) than core temperature from nine to 20 minutes post-training. The results show that there is no consistent difference between core and tympanic temperature during recovery from a simulated firefighting task across a range of different ambient conditions. Agencies should, accordingly, prioritize investigating other practical markers of core temperature as part of a broader heat stress management plan for firefighters.

One-way water-transport cotton fabrics with enhanced cooling effect

Two types of directional water transport fabrics are prepared by using cotton fabric as substrate and an electrospraying technique to apply a hydrophobic coating on one side of the fabric. The main difference between the two electrosprayed fabrics is that one of them was precoated with a hydrophilic thermoconductive resin over the fiber surface prior to electrospraying. As a result, the precoated fabric has a much higher thermoconductivity than the other, while they are similar in water transport and fibrous structure. In the wet state, the directional water-transport fabrics generate a temperature difference between the two fabric sides while drying naturally. The fabric with higher thermal conductivity shows smaller temperature difference, better thermal transfer within the fabric, stronger evaporation cooling effect, and accelerated moisture evaporation. Directional water transport fabrics with high thermal conductivity may be used to mitigate thermal burden in sportswear, summer clothing, medical fabrics, and workwear.

Heat and moisture transfer through silkworm cocoon walls.

A silkworm cocoon is a biological porous structure which provides multiple protective functions. The knowledge from this natural protective system could contribute to develop advanced materials and structures with superior performances and meet the human demanding of novel breathable materials for enhanced thermal protection and comfort.

Bifacial fabric structures and properties.

Novel bifacial fabrics, with a woven structure on one face and a knitted structure on the other, were developed and produced on a purpose-built machine using conventional fibres. Bifacial fabrics have two breakages in warp and weft directions, and better thermal comfort properties than traditional woven and knitted fabrics.

Hygienic practices among food vendors in educational institutions in Ghana: the case of Konongo

With the booming street food industry in the developing world there is an urgent need to ensure food vendors adhere to hygienic practices to protect public health. This study assessed the adherence to food hygiene practices by food vendors in educational institutions in Konongo, Ghana. Structured questionnaires, extensive observation and interviews were used for the study involving 60 food vendors from 20 basic schools. Attributable to the influence of school authorities and the level of in-training of food vendors, the study points out that food vendors in educational institutions generally adhered to good food hygiene practices, namely, regular medical examination (93%), protection of food from flies and dust (55%); proper serving of food (100%); good hand hygiene (63%); and the use of personal protective clothing (52%). The training of food vendors on food hygiene, instead of the level of education had a significant association (p < 0.05) with crucial food hygiene practices such as medical examination, hand hygiene and protection of food from flies and dust. Further, regulatory bodies legally mandated to efficiently monitor the activities of food vendors lacked the adequate capacity to do so. The study proposes that efforts should be geared towards developing training programmes for food vendors as well as capacity building of the stakeholders.