1,720,996 research outputs found
Cutaneous thermosensory mapping of the female breast and pelvis
No full textDifferences in skin thermal sensitivity have been extensively mapped across areas of the human body, including the torso, limbs, and extremities. Yet, there are parts of the female body, such as the breast and the pelvis for which we have limited thermal sensitivity data. The aim of this study was to map cutaneous warm and cold sensitivity across skin areas of the breast and pelvis that are commonly covered by female underwear. Twelve young females (21.9 ± 3.2 years) reported on a 200 mm visual analogue scale the perceived magnitude of local thermal sensations arising from short-duration (10 s) static application of a cold [5 °C below local skin temperature (Tsk)] or warm (5 °C above local Tsk) thermal probe (25 cm2) in seventeen locations over the breast and pelvis regions. The data revealed that thermal sensitivity to the warm probe, but not the cold probe, varied by up to 25% across the breast [mean difference between lowest and highest sensitivity location was 51 mm (95% CI:14, 89; p < 0.001)] and up to 23% across the pelvis [mean difference between lowest and highest sensitivity location: 46 mm (95% CI:9, 84; p = 0.001)]. The regional differences in baseline Tsk did not account for variance in warm thermal sensitivity. Inter-individual variability in thermal sensitivity ranged between 24 and 101% depending on skin location. We conclude that the skin across the female breast and pelvis presents a heterogenous distribution of warm, but not cold, thermal sensitivity. These findings may inform the design of more comfortable clothing that are mapped to the thermal needs of the female body.</p
The effect of female breast surface area on cutaneous thermal sensation, wetness perception and epidermal properties
No full textFemale development includes significant size changes across the breast. Yet, whether differences in breast surface area (BrSA) modify breast sensitivity to warm, cold and wetness, and the associated epidermal properties (skin thickness and surface roughness) remain unclear. We investigated the relationship between BrSA and thermal and wetness perception, as well as epidermal properties, in 21 females (28 ± 10 years) of varying breast sizes (BrSA range: 147-502 cm 2), at multiple breast sites (i.e., nipple, above and below the nipple, and bra triangle). Associations between BrSA and the perceptual and epidermal variables were determined via correlation analyses. Differences across test sites were assessed by repeated-measures ANOVA. Our results did not support the hypothesis that larger breasts present reduced thermal and wetness sensitivity, except for the above nipple site, which presented reduced warm sensitivity with increasing BrSA (r = -0.61, P = 0.003). We also found a heterogeneous distribution of cold, but not warm or wetness, sensitivity across the breast, with the above nipple site presenting lower cold sensitivity than any other site (P < 0.015). Our findings did not indicate any association between BrSA and epidermal properties (thickness and roughness), nor any site-dependent variation in these anatomical parameters (P > 0.15). We conclude that, while some skin-site (i.e., above the nipple) and perceptual modality-dependent (i.e., warm sensitivity) differences were observed, BrSA-dependent variations in thermal and wetness sensitivity were not a generalised feature of the skin covering the breast. These observations advance our fundamental understanding of breast sensory function, and they could inform the design of user-centred clothing such as bras
The effect of female breast surface area on heat-activated sweat gland density and output size matters!
No full textIntroduction: the production and evaporation of sweat from the skin surface is the human body’s principal method of heat loss during heat stress. By 2 years of age, our skin contains 2-5 million sweat glands [1]. The number of sweat glands does not appear to change beyond this age. Hence, sweat gland density decreases with skin expansion during physical growth [1, 2]. In contrast to men, female development includes significant morphological changes across specific body parts, such as the breast. Female breast development, and the resulting breast surface area (BrSA), can vary greatly due to genetic factors, body-mass-index and energy intake early in life. However, it is unclear whether sweat gland density further decreases as breasts grow. Sweat gland density may impact sweat output per gland for a given sweat rate [3]. This has implications for sweat accumulation in sport bras, which in turn affects breast heat balance and comfort during exercise heat stress in women of different breast sizes. This study aimed to investigate breast-size dependent, regional differences in sweat gland density and output during exercise heat stress in women with large differences in BrSA.Method: fifteen healthy females (24±7yr) with large differences in BrSA (range=147.2-480.5cm2) performed a 50-min submaximal run in a climatic chamber regulated at 33.0±0.8℃ and 53.4±2.0% RH. Sweat gland density (SGD; modified iodine technique [4]) and local sweat rates (LSR; absorbent patches [5]) were measured above and below the nipple, and at the bra triangle, during the final 5-min of exercise. Gastrointestinal (core) temperature and metabolic rate were monitored throughout the run. We used linear regression analyses to evaluate the relationship between: a) SGD and BrSA; and b) sweat output per gland (calculated as LSR/SGD) and BrSA. Furthermore, we assessed regional differences in SGD and sweat output per gland amongst the bra triangle, above and below the nipple, with a repeated-measures ANOVA.Results: SGD above (R2=0.55, p<0.01, Fig. 1A) and below the nipple (R2=0.63, p<0.01, Fig. 1B) decreased with increasing BrSA. This effect was not observed at the bra triangle (R2=0.12, p=0.101, Fig. 1C). Sweat output per gland above the nipple increased with BrSA (R2=0.29, p=0.02, Fig. 2A). This effect was not observed below the nipple (R2=0.13, p=0.10, Fig. 2B) nor at the bra triangle (R2=0.04, p=0.24, Fig. 2C). SGD was lower at both breast sites (above nipple=35.6±6.0 glands/cm2; below nipple=31.2±4.8 glands/cm2, p<0.01) than at the bra triangle (86.8±5.3glands/cm2, Fig. 3). Sweat output per gland above (343.4±39.6µg, p<0.01), but not below (416.4±62.5µg, p=0.89), the nipple was lower than at the bra triangle (690.6±76.0µg, Fig. 4).Conclusion: our findings indicate that SGD decreases and sweat output per gland increases with increasing BrSA, and that SGD and output per gland vary greatly across the breast and bra triangle. It therefore appears that, to maintain breast heat balance, individual sweat glands upregulate their activity to accommodate their lower density across larger breasts. Sport bra design may therefore consider the implications of this on sweat accumulation patterns for women of different breast, thus bra sizes. <br/
Dataset supporting: "A novel high-resolution methodology to assess temporal changes in skin wetness perception during and following wet stimuli contact."
No full text**** assigned the DOI https://doi.org/10.5258/SOTON/D3690*** Data includes wetness perception and skin temperature </span
Effects of stimulus temperature and skin hydration levels on wetness erception at the Underarm
No full textBackground: experiencing wetness on the skin because of sweating or contact with fluids can induce thermal discomfort. Millions of people apply antiperspirant deodorant products to the underarm to minimise this negative experience. However, the mechanisms underpinning wetness perception at the underarm and the influence of underlying stratum corneum hydration remain under investigation. We aimed to evaluate the role of stimulus temperature and skin hydration levels on wetness perception at the underarm in young participants.Materials and methods: ten healthy participants (5 M/5 F; 29 ± 7 years) underwent a quantitative sensory test during which they reported the perceived magnitude of wetness perception from a short-duration static application of a cold-wet (i.e., 5°C below local skin temperature), neutral-wet (i.e., equal to local skin temperature) and warm-wet (i.e., 5°C above local skin temperature) stimuli. Wetness perception was assessed on a 100-mm visual analogue scale (0 = dry; 100 = completely wet), with a repeated measures design exploring the effects of overhydration (+21 %) and dehydration (−40 %) of the underarm's skin.Results: our results indicated a higher wetness perception (p = 0.012) during the cold-wet (40 mm, 95 % CI: 25, 56) than during the warm-wet (25 mm, 95 % CI: 12, 39), and neutral-wet stimuli (24 mm, 95 % CI: 7, 40). Furthermore, overhydration of the underarm’ stratum corneum can lead to an increase in wetness perceptions upon contact with cold-wet stimuli only (mean increase: 20 mm, 95 % CI: 3, 36; p = 0.024; corresponding to 20 % increase).Conclusion: our findings provide novel fundamental insights into the underarm's perceptual responses to wetness, which could inform understanding of the determinants of wet feel associated with periods of sweating and the application of antiperspirant products
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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