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1.	Advances in Thermal Imaging 2021 In: Journal of Thermal Biology. - 0306-4565. Other publication (peer-reviewed)abstract Thermal imaging, or more correctly infrared thermography, has been widely applied to studies of animal and human biology (see Burnay et al. 1988; McCafferty 2007; Soerensen and Pedersen 2015; Fernandez-Cuevas et al., 2015; Tattersall 2016). This technique provides non-contact measurement of surface temperature, allowing real-time recording of the spatial temperature distribution of a body region, physical structure or habitat of interest. Thermal imaging technology has advanced rapidly in the last decade and is now becoming a key tool in thermal biology. Technological advances include greater spatial and temporal resolution, increased capacity to record and store high resolution radiometric video, as well as reduced device size and portability. In addition, high-quality thermal imaging devices are quickly becoming more affordable, meaning thermal imaging is an increasingly common item of the research tool-kit in many pure and applied fields. The aim of this Special Issue was to highlight how advances in thermal imaging can be used to answer important questions in biology, and to demonstrate how the combination of this technology with novel analytical methods can further advance our conceptual understanding of thermal biology.
2.	Bauerfeind, Stephanie S., et al. (author) Geographic variation in responses of European yellow dung flies to thermal stress 2018 In: Journal of Thermal Biology. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0306-4565 .- 1879-0992. ; 73, s. 41-49 Journal article (peer-reviewed)abstract Climatic conditions can be very heterogeneous even over small geographic scales, and are believed to be major determinants of the abundance and distribution of species and populations. Organisms are expected to evolve in response to the frequency and magnitude of local thermal extremes, resulting in local adaptation. Using replicate yellow dung fly (Scathophaga stercoraria; Diptera: Scathophagidae) populations from cold (northern Europe) and warm climates (southern Europe), we compared 1) responses to short-term heat and cold shocks in both sexes, 2) heat shock protein (Hsp70) expression in adults and eggs, and 3) female reproductive traits when facing short-term heat stress during egg maturation. Contrary to expectations, thermal traits showed minor geographic differentiation, with weak evidence for greater heat resistance of southern flies but no differentiation in cold resistance. Hsp70 protein expression was little affected by heat stress, indicating systemic rather than induced regulation of the heat stress response, possibly related to this fly group's preference for cold climes. In contrast, sex differences were pronounced: males (which are larger) endured hot temperatures longer, while females featured higher Hsp70 expression. Heat stress negatively affected various female reproductive traits, reducing first clutch size, overall reproductive investment, egg lipid content, and subsequent larval hatching. These responses varied little across latitude but somewhat among populations in terms of egg size, protein content, and larval hatching success. Several reproductive parameters, but not Hsp70 expression, exhibited heritable variation among full-sib families. Rather than large-scale clinal geographic variation, our study suggests some local geographic population differentiation in the ability of yellow dung flies to buffer the impact of heat stress on reproductive performance.
3.	Bayliak, Maria M., et al. (author) Dietary alpha-ketoglutarate increases cold tolerance in Drosophila melanogaster and enhances protein pool and antioxidant defense in sex-specific manner 2016 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 60, s. 1-11 Journal article (peer-reviewed)abstract Alpha-ketoglutarate (AKG) is an important intermediate in Krebs cycle which bridges the metabolism of amino acids and carbohydrates. Its effects as a dietary supplement on cold tolerance were studied in Drosophila melanogaster Canton S. Two-day-old adult flies fed at larval and adult stages with AKG at moderate concentrations (5-10 mM) recovered faster from chill coma (0 °C for 15 min or 3 h) than control ones. The beneficial effect of AKG on chill coma recovery was not found at its higher concentrations, which suggests hormetic like action of this keto acid. Time of 50% observed mortality after 2 h recovery from continuous cold exposure (-1 °C for 3-31 h) (LTi50) was higher for flies reared on 10 mM AKG compared with control ones, showing that the diet with AKG enhanced insect cold tolerance. In parallel with enhancement of cold tolerance, dietary AKG improved fly locomotor activity. Metabolic effects of AKG differed partly in males and females. In males fed on AKG, there were no differences in total protein and free amino acid levels, but the total antioxidant capacity, catalase activity and low molecular mass thiol content were higher than in control animals. In females, dietary AKG promoted higher total antioxidant capacity and higher levels of proteins, total amino acids, proline and low molecular mass thiols. The levels of lipid peroxides were lower in both fly sexes reared on AKG as compared with control ones. We conclude that both enhancement of antioxidant system capacity and synthesis of amino acids can be important for AKG-promoted cold tolerance in D. melanogaster. The involvement of AKG in metabolic pathways of Drosophila males and females is discussed.
4.	Bezerra Lima Verde, Isabel, et al. (author) Effect of season on bovine seminal plasma proteins in Thailand 2020 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 90 Journal article (peer-reviewed)abstract Although season has been shown to affect bull sperm quality and fertility in some studies, the effect of season on seminal plasma proteins has not been examined. In the present study, seminal plasma proteins were analysed by Fast Protein Liquid Chromatography (FPLC), to separate the phosphorylcholine-binding proteins and heparin-binding proteins from the other proteins. Semen samples were collected from bulls in three seasons: winter, summer and the rainy season. Sperm quality was analysed by flow cytometry and computer assisted sperm analysis, and further aliquots of semen were used to prepare the seminal plasma for FPLC. Meteorological data were available from a location close to the bull station. There were slight differences in sperm kinematics between seasons, but other parameters of sperm quality were not different. Minor differences in the phosphorylcholine-binding proteins were detected according to season, being lower in summer than in winter or in the rainy season, although there were no changes in the heparin-binding proteins. Temperature, humidity and rainfall differed between winter and the rainy season, but no differences were observed between summer and the rainy season except in the temperature humidity index (THI). However, the THI was above the threshold indicative of heat stress in all seasons, which could explain why few seasonal differences in protein composition were detected in this study. Alternatively, the bulls could have been well-adapted to heat stress. In conclusion, there were only slight differences in bull sperm quality and seminal plasma proteins between seasons during this study.
5.	Björn, Lars Olof, et al. (author) Thermal emissivity of avian eggshells 2016 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565 .- 1879-0992. ; 57, s. 1-5 Journal article (peer-reviewed)abstract The hypothesis has been tested that evolution has resulted in lower thermal emissivity of eggs of birds breeding openly in cold climates than of eggs of birds that nest under protective covering or in warmer climates. Directional thermal emissivity has been estimated from directional–hemispherical reflectance spectra. Due to several methodological difficulties the absolute emissivity is not accurately determined, but differences between species are obvious. Mostnotably, small waders of the genus Calidris, breeding in cold climates on the tundra, and in most cases with uniparental nest attendance, have low directional emissivity of their eggshells, about 0.92 when integration is carried out for wavelengths up to 16 μm. Species belonging to Galloanserinae have the highest directional emissivity, about 0.96, of their eggs. No differences due to climate or breeding conditions were found within this group. Eggs of most other birds tested possess intermediate emissivity, but the values for Pica pica and Corvus corone cornix are as low as for Calidris. Large species-dependent differences in spectral reflectance were found at specific wavelengths. For instance, at 4.259 μm the directional–hemispherical reflectance for galliforms range from 0.05 to 0.09, while for Fratercula arctica and Fulmarus glacialis it is about 0.3.The reflection peaks at 6.5 and 11.3 μm due to calcite are differentially attenuated in differents pecies. In conclusion, the hypothesis that evolution has resulted in lower thermal emissivity of bird-eggs being exposed in cold climates is not supported by our results.The emissivity is not clearly related to nesting habits or climate, and it is unlikely that the small differences observed are ecologically important. The spectral differences between eggs that nevertheless exist should be taken into account when using infrared thermometers for estimating the surface temperature of avian eggs.
6.	Blanckenhorn, Wolf U., et al. (author) Comprehensive thermal performance curves for yellow dung fly life history traits and the temperature-size-rule 2021 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565 .- 1879-0992. ; 100 Journal article (peer-reviewed)abstract Ambient temperature strongly determines the behaviour, physiology, and life history of all organisms. The technical assessment of organismal thermal niches in form of now so-called thermal performance curves (TPC) thus has a long tradition in biological research. Nevertheless, several traits do not display the idealized, intuitive dome-shaped TPC, and in practice assessments often do not cover the entire realistic or natural temperature range of an organism. We here illustrate this by presenting comprehensive sex-specific TPCs for the major (juvenile) life history traits of yellow dung flies (Scathophaga stercoraria; Diptera: Scathophagidae). This concerns estimation of prominent biogeographic rules, such as the temperature-size-rule (TSR), the common phenomenon in ectothermic organisms that body size decreases as temperature increases. S. stercoraria shows an untypical asymptotic TPC of continuous body size increase with decreasing temperature without a peak (optimum), thus following the TSR throughout their entire thermal range (unlike several other insects presented here). Egg-to-adult mortality (our best fitness estimator) also shows no intermediate maximum. Both may relate to this fly entering pupal winter diapause below 12 °C. While development time presents a negative exponential relationship with temperature, development rate and growth rate typify the classic TPC form for this fly. The hitherto largely unexplored close relative S. suilla with an even more arctic distribution showed very similar responses, demonstrating large overlap among two ecologically similar, coexisting dung fly species, thus implying limited utility of even complete TPCs for predicting species distribution and coexistence.
7.	Cardinale, Massimiliano (author) Heat loss in sleeping Garden Warblers (Sylvia borin) during migration 2020 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 94 Journal article (peer-reviewed)abstract For small songbirds, energy is often a limiting factor during migration and, for this reason, they are forced to alternate nocturnal flights with stopovers to rest and replenish energy stores. Stopover duration has a key role for a successful migration and may have an important impact on fitness. Thus, migrants need to optimize their energy consumption at this stage to reduce their permanence at the site. A recent study has shown that lean individuals reduce their metabolic rate when tucking the head in the feathers during sleep. The underlying mechanism is very likely a reduction in conductance, but the thermoregulatory benefit of the increased insulation has never been quantified yet. Here, we compared heat loss in individual migratory birds while sleeping in different postures. Using a thermal camera and a within-individual approach, we estimated that Garden Warblers can reduce their rate of heat loss by 54% by sleeping with the head tucked in the feathers. This energy saving has a relevant impact on the individual’s energy balance because it can account for up to 8.69% of daily energy expenditure during stopover. Our study provides novel and important information to understand the fundamental role of thermoregulatory strategies on bird’s energy management.
8.	Ciuha, Ursa, et al. (author) Effects of normobaric hypoxic bed rest on the thermal comfort zone 2015 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565 .- 1879-0992. ; 49-50, s. 39-46 Journal article (peer-reviewed)abstract Future Lunar and Mars habitats will maintain a hypobaric hypoxic environment to minimise the risk of decompression sickness during the preparation for extra-vehicular activity. This study was part of a larger study investigating the separate and combined effects of inactivity associated with reduced gravity and hypoxia, on the cardiovascular, musculoskeletal, neurohumoural, and thermoregulatory systems. Eleven healthy normothermic young male subjects participated in three trials conducted on separate occasions: (1) Normobaric hypoxic ambulatory confinement, (2) Normobaric hypoxic bedrest and (3) Normobaric normoxic bedrest Normobaric hypoxia was achieved by reduction of the oxygen fraction in the air (FiO2=0.141 +/- 0.004) within the facility, while the effects of reduced gravity were simulated by confining the subjects to a horizontal position in bed, with all daily routines performed in this position for 21 days. The present study investigated the effect of the interventions on behavioural temperature regulation. The characteristics of the thermal comfort zone (TCZ) were assessed by a water-perfused suit, with the subjects instructed to regulate the sinusoidally varying temperature of the suit within a range considered as thermally comfortable. Measurements were performed 5 days prior to the intervention (D-5), and on days 10 (D10) and 20 (D20) of the intervention. no statistically significant differences were found in any of the characteristics of the TCZ between the interventions (HAMB, HBR and NBR), or between different measurement days (D-5, D10, D20) within each intervention. rectal temperature remained stable, whereas skin temperature (T-sk) increased during all interventions throughout the one hour trial, no difference in T-sk between 0-5, D10 and D20, and between HAMB, HBR and NBR were revealed, subjects perceived the regulated temperature as thermally comfortable, and neutral or warm, we conclude that regulation of thermal comfort is not compromised by hypoxic inactivity. (C) 2015 Elsevier Ltd. All rights reserved.
9.	Del Ferraro, Simona, et al. (author) Mitigating heat effects in the workplace with a ventilation jacket : simulations of the whole-body and local human thermophysiological response with a sweating thermal manikin in a warm-dry environment 2024 In: Journal of Thermal Biology. - 0306-4565. ; 119 Journal article (peer-reviewed)abstract Climate change is increasingly affecting human well-being and will inevitably impact on occupational sectors in terms of costs, productivity, workers' health and injuries. Among the cooling garment developed to reduce heat strain, the ventilation jacket could be considered for possible use in workplaces, as it is wearable without limiting the user's mobility and autonomy. In this study, simulations with a sweating manikin are carried out to investigate the effects of a short-sleeved ventilation jacket on human thermophysiological responses in a warm-dry scenario. Simulations were performed in a climatic chamber (air temperature = 30.1 °C; air velocity = 0.29 m/s; relative humidity = 30.0 %), considering two constant levels of metabolic rate M (M 1 = 2.4 MET; M 2 = 3.2 MET), a sequence of these two (Work), and three levels of fan velocities (l f = 0; l f=2; l f=4). The results revealed a more evident impact on the mean skin temperature (T sk) compared to the rectal temperature (T re), with significant decreases (compared to fan-off) at all M levels, for T sk from the beginning and for T re from the 61 st minute. Skin temperatures of the torso zones decreased significantly (compared to fan-off) at all M levels, and a greater drop was registered for the Back. The fans at the highest level (l f=4) were significantly effective in improving whole-body and local thermal sensations when compared to fan-off, at all M levels. At the intermediate level (l f=2), the statistical significance varied with thermal zone, M and time interval considered. The results of the simulations also showed that the Lower Torso needs to be monitored at M 2 level, as the drop in skin temperature could lead to local overcooling and thermal discomfort. Simulations showed the potential effectiveness of the ventilation jacket, but human trials are needed to verify its cooling power in real working conditions.
10.	Ekström, Andreas, 1979, et al. (author) Effects of autonomic blockade on acute thermal tolerance and cardioventilatory performance in rainbow trout, Oncorhynchus mykiss 2014 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 44, s. 47-54 Journal article (peer-reviewed)abstract Predicted future increases in global temperature may impose challenges for ectothermic animals like fish, but the physiological mechanisms determining the critical thermal maximum (CTmax) are not well understood. One hypothesis suggests that impaired cardiac performance, limited by oxygen supply, is an important underlying mechanism. Since vagal bradycardia is suggested to improve cardiac oxygenation and adrenergic stimulation may improve cardiac contractility and protect cardiac function at high temperatures, we predicted that pharmacological blockade of cardiac autonomic control would lower CTmax. Rainbow trout was instrumented with a flow probe and a ventilation catheter for cardioventilatory recordings and exposed to an acute thermal challenge until CTmax following selective pharmacological blockade of muscarinic or beta-adrenergic receptors. Contrary to our prediction, CTmax (~26 degrees C) was unchanged between treatments. While beta-adrenergic blockade reduced heart rate it did not impair cardiac stroke volume across temperatures suggesting that compensatory increases in cardiac filling pressure may serve to maintain cardiac output. While warming resulted in significant tachycardia and increased cardiac output, a high cholinergic tone on the heart was observed at temperatures approaching CTmax. This may represent a mechanism to maintain scope for heart rate and possibly to improve myocardial contractility and oxygen supply at high temperatures. This is the first study evaluating the importance of autonomic cardiac control on thermal tolerance in fish. While no effects on CTmax were observed, this study raises important questions about the underlying mechanisms determining thermal tolerance limits in ectothermic animals.
11.	Gläser, Nele, et al. (author) Variation in rhinarium temperature indicates sensory specializations in placental mammals 2017 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 67, s. 30-34 Journal article (peer-reviewed)abstract The rhinarium, a specialized nose-tip characterized by an area of naked and wet skin around the nostrils, is a typical mammalian structure. The type and amount of innervation suggests a sensory role and morphological diversity implies so far unidentified species-specific functional specializations. Rhinaria also vary in temperature and this may be related to the functions of these sensory organs. We performed a comparative study on rhinarium temperature in order to learn more about possible correlations with phylogeny and ecology. We have concentrated on terrestrial carnivorans and large herbivores, but also investigated a number of other species, some of them lacking typical rhinaria. We used infrared (IR) thermography to determine nose skin temperatures from safe distances and without interfering with the animals’ behavior. In all groups studied, the temperature of the rhinarium/nose-tip decreased with decreasing ambient temperature. At all ambient temperatures, rhinarium temperature was lower, by 9–17 °C, in carnivorans compared to herbivores. Glires (rodents and lagomorphs), haplorrhine primates, and omnivorous Perisso- and Artiodactyla were intermediate. In strepsirrhine primates, rhinarium temperature was similar to ambient temperature. Our findings in Strepsirrhini are consistent with the hypothesis that their rhinaria have an indirect role in chemical communication. Warm rhinaria in herbivores suggest a tactile function, while the low skin temperatures on carnivoran rhinaria may make the skin particularly sensitive to warming.
12.	Hansson, Erik, 1987, et al. (author) An explorative study of inflammation-related proteins associated with kidney injury in male heat-stressed workers 2023 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 112 Journal article (peer-reviewed)abstract Chronic kidney disease of non-traditional origin (CKDnt) and acute kidney injury (AKI) often affect heat-stressed Mesoamerican manual workers. Inflammation occurs concurrently with AKI in this population, but its role remains unknown. To explore links between inflammation and kidney injury in heat stress, we compared levels of inflammation-related proteins in cutters with and without increasing serum creatinine levels during sugarcane harvest. These sugarcane cutters have previously been identified to be repeatedly exposed to severe heat stress during the five month harvest season. A nested case-control study was conducted among male Nicaraguan sugarcane cutters in a CKDnt hotspot. Cases (n = 30) were defined as having an increase in creatinine of >= 0.3 mg/dL across the five-month harvest. Controls (n = 57) had stable creatinine levels. Ninety-two inflammation-related proteins in serum were measured before and after harvest using Proximity Extension Assays. Mixed linear regression was used to identify differences in protein concentrations between cases and controls before harvest, differential trends during harvest, and association between protein concentrations and the urine kidney injury markers Kidney Injury Molecule (KIM)-1, Monocyte Chemoattractant Protein (MCP)-1 and albumin. One protein, chemokine (C-C motif) ligand 23 (CCL23), was elevated among cases at pre-harvest. Changes in seven inflammation-related proteins (CCL19, CCL23, colony-stimulating factor 1 [CSF1], hepatocyte and fibroblast growth factors [HGF and FGF23], and tumor necrosis factor beta [TNFB] and TNF-related activation -induced cytokine [TRANCE]) were associated with case status and at least two out of three urine kidney injury markers (KIM-1, MCP-1 and albumin). Several of these have been implicated in myofibroblast activation, which likely is an important step in kidney interstitial fibrotic disease such as CKDnt. This study provides an initial exploration of immune system determinants of, and activation during, kidney injury experienced during prolonged heat stress.
13.	Keramidas, Michail, et al. (author) In Shackleton’s trails : central and local thermoadaptive modifications to cold and hypoxia after a man-hauling expedition on the Antarctic Plateau 2018 In: Journal of Thermal Biology. - : Elsevier. - 0306-4565 .- 1879-0992. ; 73, s. 80-90 Journal article (peer-reviewed)abstract Cold and hypoxia constitute the main environmental stressors encountered on the Antarctic Plateau. Hence, we examined whether central and/or peripheral acclimatisation to the combined stressors of cold and hypoxia would be developed in four men following an 11-day man-hauling expedition on this polar region. Before and after the journey, participants performed a static whole-body immersion in 21 degrees C water, during which they were breathing a hypoxic gas (partial pressure of inspired 02: 97 mmHg). To evaluate their local responses to cold, participants also immersed the hand into 8 degrees C water for 30 min, while they were whole-body immersed and mildly hypothermic [i.e. 0.5 degrees C fall in rectal temperature (T-rec) from individual pre-immersion values]. T-rec, and aldn temperature (T-ak), skin blood flux, and oxygen uptake (reflecting shivering thermogenesis) were monitored throughout. The polar expedition accelerated by similar to 14 min the drop in Trr, [final mean (95% confidence interval) changes in T-rec: Before = -0.94 (0.15) degrees C, After: 1.17 (0.23) degrees C]. The shivering onset threshold [Before: 19 (22) min, After: 25 (19) min] and gain [Before: 4.19 (3.95) mL min(-1) kg, After: 1.70 (1.21) mi. min(-1) kg(-1)] were suppressed by the expedition. TA did not differ between trials. The development of a greater post expedition hypothermic state did not compromise finger circulation during the hand-cooling phase. Present findings indicate therefore that a hypothermic pattern of cold acclimatisation, as investigated in hypoxia, was developed following a short-term expedition on the South Polar Plateau; an adaptive response that is characterised mainly by suppressed shivering thermogenesis, and partly by blunted cutaneous vasoconstriction.
14.	Kjaersgaard, Anders, et al. (author) Weak sex-specific evolution of locomotor activity of Sepsis punctum (Diptera : Sepsidae) thermal experimental evolution lines 2023 In: Journal of Thermal Biology. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0306-4565 .- 1879-0992. ; 116 Journal article (peer-reviewed)abstract Elevated temperatures are expected to rise beyond what the physiology of many organisms can tolerate. Behavioural responses facilitating microhabitat shifts may mitigate some of this increased thermal selection on physiology, but behaviours are themselves mediated by physiology, and any behavioural response may trade-off against other fitness-related activities. We investigated whether experimental evolution in different thermal regimes (Cold: 15 degrees C; Hot: 31 degrees C; Intergenerational fluctuation 15/31 degrees C; Control: 23 degrees C) resulted in genetic differentiation of standard locomotor activity in the dung fly Sepsis punctum. We assessed individual locomotor performance, an integral part of most behavioral repertoires, across eight warm temperatures from 24 degrees C to 45 degrees C using an automated device. We found no evidence for generalist-specialist trade-offs (i.e. changes in the breadth of the performance curve) for this trait. Instead, at the warmest assay temperatures hot-selected flies showed somewhat higher maximal performance than all other, especially cold-selected flies, overall more so in males than females. Yet, the flies' temperature optimum was not higher than that of the cold-selected flies, as expected under the 'hotter-is-better' hypothesis. Maximal locomotor performance merely weakly increased with body size. These results suggest that thermal performance curves are unlikely to evolve as an entity according to theory, and that locomotor activity is a trait of limited use in revealing thermal adaptation.
15.	Kounalakis, Stylianos N., et al. (author) A 10-day confinement to normobaric hypoxia impairs toe, but not finger temperature response during local cold stress 2017 In: Journal of Thermal Biology. - : Elsevier. - 0306-4565 .- 1879-0992. ; 64, s. 109-115 Journal article (peer-reviewed)abstract The study examined the effects of a 10-day normobaric hypoxic confinement on the finger and toe temperature responses to local cooling. Eight male lowlanders underwent a normoxic (NC) and, in a separate occasion, a normobaric hypoxic confinement (HC; FO2: 0.154; simulated altitude ~3400 m). Before and after each confinement, subjects immersed for 30 min their right hand and, in a different session, their right foot in 8 °C water, while breathing either room air (AIR) or a hypoxic gas mixture (HYPO). Throughout the cold-water immersion tests, thermal responses were monitored with thermocouples on fingers and toes. Neither confinement influenced thermal responses in the fingers during the AIR or HYPO test. In the foot, by contrast, HC, but not NC, reduced the average toe temperature by ~1.5 °C (p=0.03), both during the AIR and HYPO test. We therefore conclude that a 10-day confinement to normobaric hypoxia per se augments cold-induced vasoconstriction in the toes, but not in the fingers. The mechanism underlying this dissimilarity remains to be established.
16.	Kröger, Ronald Heinz Herbert, et al. (author) Rhinarium temperature dynamics in domestic dogs 2017 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 70, s. 15-19 Journal article (peer-reviewed)abstract Many mammals have specialized nose-tips with glabrous and often wet skin, called rhinaria. The function of the rhinarium is unknown in most species. Rhinaria differ not only in shape and skin structure, but also in skin temperature. They are considerably colder in carnivorans than in herbivorous artio- and perissodactyls. Domestic dogs are carnivorans and their noses often feel cold, such that they can be used as an abundant and easily accessible model species. We performed a study on rhinarium temperature in dogs under various ambient temperatures as well as in different behavioral and physiological contexts, breeds, and age groups. The rhinaria of adult, alert, and comfortable dogs are colder than ambient temperature from 30 °C (approximately 5 °C colder) down to a break point at about 15 °C. At an ambient temperature of 0 °C, rhinarium temperature is approximately 8 °C and the decrease in skin surface temperature with decreasing ambient temperature has not yet leveled off. The dog rhinarium warms up under a number of circumstances. In contrast to the continuously warm rhinaria of herbivores, our results suggest strongly that the cold state is the operating state of the dog rhinarium.
17.	Leijon-Sundqvist, Katarina, et al. (author) Relation between dorsal and palmar hand skin temperatures during a cold stress test 2017 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565 .- 1879-0992. ; 66, s. 87-92 Journal article (peer-reviewed)abstract Hand skin temperature measurements have previously been performed on either dorsal or palmar sides and it is possible to find arguments for the advantage of both locations. Therefore, the aim of this study was to use dynamic infrared (IR) imaging to examine the relationship between dorsal and palmar hand skin temperature. The palmar and dorsal hand skin temperature before and after a cold stress test was measured with IR thermography in 112 healthy participants. Calculation of surface average temperature was made from nine regions of interest on each hand's dorsal and palmar side. Temperature values were recorded at baseline, directly after immersion of hands in vinyl gloves for one minute in water at 20 +/- 0.5 degrees C (gloves removed), and after eight minutes rewarming. Results showed that: a) the skin temperatures on the dorsal and palmar sides of the hand are strongly correlated; b) the correlation is stronger on the fingers than on the carpometacarpal (CMC) area; c) the palmar side of the CMC area is warmer than the dorsal side, but this is reversed in the fingers so that the nail bed is warmer than the finger pad; and d) the temperature difference Delta T between the dorsal and palmar sides of the fingers is independent of the skin temperature, though Delta T on the CMC area of the hand is temperature dependent. Such differences can be important in detailed investigations of thermal phenomena in the hand. In conclusion, results showed a strong correlation between the dorsal and palmar temperatures. If both sides cannot be measured, the purpose of the investigation should determine which side of the hand should be measured.
18.	Lewden, Agnès, et al. (author) The metabolic cost of subcutaneous and abdominal rewarming in king penguins after long-term immersion in cold water 2020 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 91 Journal article (peer-reviewed)abstract Marine endotherms in the polar regions face a formidable thermal challenge when swimming in cold water. Hence, they use morphological (fat, blubber) adjustment and peripheral vasoconstriction to reduce demands for heat production in water. The animals then regain normothermia when resting ashore. In the king penguin (Aptenodytes patagonicus) metabolic rate is lower in fed than in fasted individuals during subsequent rewarming on land. This has been suggested to be a consequence of diversion of blood flow to the splanchnic region in fed birds, which reduces peripheral temperatures. However, peripheral temperatures during recovery have never been investigated in birds with different nutritional status. The aim of this study was, therefore, to measure subcutaneous and abdominal temperatures during the rewarming phase on land in fasted and fed king penguins, and investigate to which extent any different rewarming were reflected in recovery metabolic rate (MRR) after long term immersion in cold water. We hypothesized that fed individuals would have a slower increase of subcutaneous temperatures compared to fasted penguins, and a correspondingly lower MRR. Subcutaneous tissues reached normothermia after 24.15 (back) and 21.36 min (flank), which was twice as fast as in the abdomen (46.82 min). However, recovery time was not affected by nutritional condition. MRR during global rewarming (4.56 ± 0.42 W kg−1) was twice as high as resting metabolic rate (RMR; 2.16 ± 0.59 W kg−1). However, MRR was not dependent on feeding status and was significantly elevated above RMR only until subcutaneous temperature had recovered. Contrary to our prediction, fed individuals did not reduce the subcutaneous circulation compared to fasted penguins and did not show any changes in MRR during subsequent recovery. It seems likely that lower metabolic rate in fed king penguins on land reported in other studies might not have been caused primarily by increased circulation to the visceral organs.
19.	Lu, Yehu, et al. (author) A novel personal cooling system (PCS) incorporated with phase change materials (PCMs) and ventilation fans: An investigation on its cooling efficiency 2015 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 52, s. 137-146 Journal article (peer-reviewed)abstract Personal cooling systems (PCS) have been developed to mitigate the impact of severe heat stress for humans working in hot environments. It is still a great challenge to develop PCSs that are portable, inexpensive, and effective. We studied the performance of a new hybrid PCS incorporating both ventilation fans and phase change materials (PCMs). The cooling efficiency of the newly developed PCS was investigated on a sweating manikin in two hot conditions: hot humid (HH, 34 °C, 75% RH) and hot dry (HD, 34 °C, 28% RH). Four test scenarios were selected: fans off with no PCMs (i.e., Fan-off, the CONTROL), fans on with no PCMs (i.e., Fan-on), fans off with fully solidified PCMs (i.e., PCM+Fan-off), and fans on with fully solidified PCMs (i.e., PCM+Fan-on). It was found that the addition of PCMs provided a 54∼78 min cooling in HH condition. In contrast, the PCMs only offered a 19–39 min cooling in HD condition. In both conditions, the ventilation fans greatly enhanced the evaporative heat loss compared with Fan-off. The hybrid PCS (i.e., PCM+Fan-on) provided a continuous cooling effect during the three-hour test and the average cooling rate for the whole body was around 111 and 315 W in HH and HD conditions, respectively. Overall, the new hybrid PCS may be an effective means of ameliorating symptoms of heat stress in both hot-humid and hot-dry environments.
20.	Lundgren Kownacki, Karin, et al. (author) Human responses in heat – comparison of the Predicted Heat Strain and the Fiala multi-node model for a case of intermittent work. 2017 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 70, s. 45-52 Journal article (peer-reviewed)abstract Two mathematical models of human thermal regulation include the rational Predicted Heat Strain (PHS) and the thermophysiological model by Fiala. The approaches of the models are different, however, they both aim at providing predictions of the thermophysiological responses to thermal environments of an average person. The aim of this study was to compare and analyze predictions of the two models against experimental data. The analysis also includes a gender comparison. The experimental data comprised of ten participants (5 males, 5 females, average anthropometric values were used as input) conducting an intermittent protocol of rotating tasks (cycling, stacking, stepping and arm crank) of moderate metabolic activities (134-291 W/m2) with breaks in-between in a controlled environmental condition (34°C, 60% RH). The validation consisted of the predictions’ comparison against experimental data from 2.5 hours of data of rectal temperature and mean skin temperature based on contact thermometry from four body locations. The PHS model over-predicted rectal temperatures during the first activity for males and the cooling effectiveness of sweat in the recovery periods, for both males and females. As a result, the PHS simulation underestimated the thermal strain in this context. The Fiala model accurately predicted the rectal temperature throughout the exposure. The fluctuation of the experimental mean skin temperature was not reflected in any of the models. However, the PHS simulation model showed better agreement than the Fiala model. As both models predicted responses more accurately for males than females, we suggest that in future development of the models it is important to take this result into account. The paper further discusses possible sources of the observed discrepancies and concludes with some suggestions for modifications.
21.	Luomala, Matti J., et al. (author) Adding a cooling vest during cycling improves performance in warm and humid conditions 2012 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 37:1, s. 47-55 Journal article (peer-reviewed)abstract It is known that warm and humid environment reduces human physical performance. The present study examined whether the use of an ice-vest in such conditions can improve cycling performance. Seven participants cycled with consecutive, non-stop, 10-minute cycles of nine minutes at 60% of their (V) over dot O-2 max punctuated by a one-minute sprint at 80% (V) over dot O-2 max. The cycling protocol was continuously repeated until exhaustion. The protocol was performed with the ice-vest (ICE), worn after 30 min of cycling, and without the ice-vest throughout the protocol (CON). Ventilatory and thermal responses were continuously recorded. Electromyographic (EMG) signals from four muscles of the dominant leg were recorded over one minute, and subjective sensations were evaluated at 10-minute intervals. At exhaustion, the exercise time was recorded. Exercise time improved significantly while wearing the ice-vest from 61 min and 29 s to 74 min and 14 s (+21.5% +/- 7.6: p <0.05). Mean power frequency and amplitude of the EMG revealed decreased neuromuscular fatigue during ICE compared to CON. Ventilatory responses indicated a tendency towards lower ventilation, respiratory quotient was significantly lower and both thermal parameters and subjective sensations indicated lower thermal strain during ICE in comparison to CON. These results suggest that wearing an ice-vest during cycling in warm and humid conditions decreases thermal and physical strain, thereby improving cycling performance. (C) 2011 Elsevier Ltd. All rights reserved.
22.	McCafferty, Dominic J., et al. (author) Editorial : Advances in thermal imaging 2021 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 102 Journal article (peer-reviewed)
23.	Moradinour, Zahra, 1989-, et al. (author) Exposure to elevated temperature during development affects eclosion and morphology in the temperate Pieris napi butterfly (Lepidoptera Pieridae) 2023 In: Journal of Thermal Biology. - 0306-4565 .- 1879-0992. ; 118 Journal article (peer-reviewed)abstract Global warming has been identified as one of the main drivers of population decline in insect pollinators. One aspect of the insect life cycle that would be particularly sensitive to elevated temperatures is the developmental transition from larva to adult. Temperature-induced modifications to the development of body parts and sensory organs likely have functional consequences for adult behaviour. To date, we have little knowledge about the effect of sub-optimal temperature on the development and functional morphology of different body parts, particularly sensory organs, in ectothermic solitary pollinators such as butterflies. To address this knowledge gap, we exposed the pupae of the butterfly Pieris napi to either 23 degrees C or 32 degrees C and measured the subsequent effects on eclosion, body size and the development of the wings, proboscis, eyes and antennae. In comparison to individuals that developed at 23 degrees C, we found that exposure to 32 degrees C during the pupal stage increased mortality and decreased time to eclose. Furthermore, both female and male butterflies that developed at 32 degrees C were smaller and had shorter proboscides, while males had shorter antennae. In contrast, we found no significant effect of rearing temperature on wing and eye size or wing deformity. Our findings suggest that increasing global temperatures and its corresponding co-stressors, such as humidity, will impact the survival of butterflies by impairing eclosion and the proper development of body and sensory organs.
24.	Pertoldi, C, et al. (author) Evolutionary aspects of climate-induced changes and the need for multidisciplinarity 2007 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 32:3, s. 118-124 Journal article (peer-reviewed)abstract An integrated view on the possible effects of global climate change is provided while taking into account that not only the rising average temperature is likely to impact natural populations but also that increased variation around the mean and higher frequency of extreme events will be important. We propose that complex genetic effects in concert with demographic patterns may affect how focal populations react to the environmental challenge in an adaptive way (if they can). In order to aim for an inclusive picture of the ongoing environmental change we argue for a synthesis of knowledge from a range of 'classical' disciplines such as quantitative genetics, conservation genetics and population ecology. A hereto little exposed concern is the importance of the increase in amplitude of environmental fluctuations and how the corresponding evolutionary and ecological reactions are expected to occur. Due to the complex interactions between the ecological and genetic mechanisms in the response to climate-induced impacts interdisciplinary approaches are the most promising path in seeking knowledge about the present and future changes in the biosphere.
25.	Sandblom, Erik, 1978, et al. (author) Thermal acclimation and acute temperature effects on cardiac barostatic reflexes in rainbow trout (Oncorhynchus mykiss). 2022 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 109 Journal article (peer-reviewed)
26.	Sepúlveda-Rodríguez, Guadalupe, 1995-, et al. (author) Bumblebee thermoregulation at increasing temperatures is affected by behavioral state 2024 In: Journal of Thermal Biology. - 0306-4565 .- 1879-0992. ; 121 Journal article (peer-reviewed)abstract Over the past decades, increasing environmental temperatures have been identified as one of the causes of major insect population declines and biodiversity loss. However, it is unclear how these rising temperatures affect endoheterothermic insects, like bumblebees, that have evolved thermoregulatory capacities to exploit cold and temperate habitats. To investigate this, we measured head, thoracic, and abdominal temperature of bumblebee (Bombus terrestris) workers across a range of temperatures (24 °C–32 °C) during three distinct behaviors. In resting bumblebees, the head, abdomen, and thorax conformed to the environmental temperature. In pre-flight bumblebees, the head and abdominal temperatures were elevated with respect to the environmental temperature, while the thoracic temperature was maintained, indicating a pre-flight muscle warming stage. In post-flight bumblebees, abdominal temperature increased at the same rate as environmental temperature, but the head and the thoracic temperature did not. By calculating the excess temperature ratio, we show that thermoregulation in bumblebees during flight is partially achieved by the active transfer of heat produced in the thorax to the abdomen, where it can more easily be dissipated. These results provide the first indication that the thermoregulatory abilities of bumblebees are plastic and behavior dependent. We also show that the flight speed and number of workers foraging increase with increasing temperature, suggesting that bees do not avoid flying at these temperatures despite its impact on behavioral performance.
27.	Sorensen, Jesper Givskov, et al. (author) Complex patterns of geographic variation in heat tolerance and Hsp70 expression levels in the common frog Rana temporaria 2009 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565 .- 1879-0992. ; 34:1, s. 49-54 Journal article (peer-reviewed)abstract 1. We tested for geographical variation in heat tolerance and Hsp70 expression levels of Rana temporaria tadpoles along a 1500 km long latitudinal gradient in Sweden. 2. Temperature tolerance of the hatchling tadpoles did not differ among populations, but they tolerated stressful hot temperatures better than 2 weeks older tadpoles. 3. Among 2-week old tadpoles, the southern population tolerated 32 C better than tadpoles from other populations. A parallel difference was found in Hsp70 expression, with the southern population showing the highest expression level. Nevertheless, at a highly stressful temperature (36 C) the northern population showed highest tolerance. 4. The heat shock pre-treatment increased heat tolerance of the tadpoles. The possible adaptive role of Hsp70 for thermal tolerance and climatic adaptation in R. temporaria tadpoles is discussed.
28.	Stenbacka, Fredrik, et al. (author) Body temperature patterns during pregnancy and parturition in moose 2022 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 109 Journal article (peer-reviewed)abstract Gestation and lactation have high energetic requirements. Up to three-fourths of the gestation period in moose (Alces alces) overlaps with the food-scarce period in winter. During this period, moose deal with the limited forage resources available through hypometabolism with decreased heart rate and body temperature (Tb). Body temperature is also an indicator of oestrus, pregnancy and parturition, which is well documented in several domestic species. In this study, we sought to determine if moose displayed a similar Tb pattern during pregnancy and parturition to domesticated ruminants, and if we could detect parturition by combining Tb and activity data. We studied the Tb pattern of 30 free-ranging adult female moose (>= 1.5 years old), equipped with ruminal temperature loggers and GPS collars. We documented a 0.13-0.19 degrees C higher Tb in pregnant compared to non-pregnant moose, depending on the study area with the Tb difference increasing along a south-north gradient, and a drop in Tb and in activity when parturition was imminent. Detection of parturition was highly successful when combining Tb and activity data with an accuracy of 91.5%. Our findings demonstrate that Tb responses to pregnancy and parturition in a wild capital-breeding ruminant are similar to those of domesticated ruminants.
29.	Stone, David W., et al. (author) Plumage development and environmental factors influence surface temperature gradients and heat loss in wandering albatross chicks 2021 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 97 Journal article (peer-reviewed)abstract Young birds in cold environments face a range of age-specific thermal challenges. Studying the thermal biology of young birds throughout ontogeny may further our understanding of how such challenges are met. We investigated how age and environmental parameters influenced surface temperature gradients across various body regions of wandering albatross (Diomedea exulans) chicks on Bird Island, South Georgia. This study was carried out over a 200 d period during the austral winter, from the end of the brood-guard period until fledging, bridging a gap in knowledge of surface temperature variation and heat loss in developing birds with a long nestling stage in severe climatic conditions. We found that variation in surface temperature gradients (i.e. the difference between surface and environmental temperature) was strongly influenced by chick age effects for insulated body regions (trunk), with an increase in the surface temperature gradient that followed the progression of plumage development, from the second set of down (mesoptiles), to final chick feathers (teleoptiles). Environmental conditions (primarily wind speed and relative humidity) had a stronger influence on the gradients in uninsulated areas (eye, bill) than insulated regions, which we interpret as a reflection of the relative degree of homeothermy exhibited by chicks of a given age. Based on biophysical modelling, total heat loss of chicks was estimated to increase linearly with age. However, mass specific heat loss decreased during the early stages of growth and then subsequently increased. This was attributed to age-related changes in feather growth and activity that increased surface temperature and, hence, metabolic heat loss. These results provide a foundation for further work on the effects of environmental stressors on developing chicks, which are key to understanding the physiological responses of animals to changes in climate in polar regions.
30.	Szafrańska, Paulina Anna, et al. (author) Deep body and surface temperature responses to hot and cold environments in the zebra finch 2020 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 94 Journal article (peer-reviewed)abstract Global warming increasingly challenges thermoregulation in endothermic animals, particularly in hot and dry environments where low water availability and high temperature increase the risk of hyperthermia. In birds, un-feathered body parts such as the head and bill work as ‘thermal windows’, because heat flux is higher compared to more insulated body regions. We studied how such structures were used in different thermal environments, and if heat flux properties change with time in a given temperature. We acclimated zebra finches (Taeniopygia guttata) to two different ambient temperatures, ‘cold’ (5 °C) and ‘hot’ (35 °C), and measured the response in core body temperature using a thermometer, and head surface temperature using thermal imaging. Birds in the hot treatment had 10.3 °C higher head temperature than those in the cold treatment. Thermal acclimation also resulted in heat storage in the hot group: core body temperature was 1.1 °C higher in the 35 °C group compared to the 5 °C group. Hence, the thermal gradient from core to shell was 9.03 °C smaller in the hot treatment. Dry heat transfer rate from the head was significantly lower in the hot compared to the cold treatment after four weeks of thermal acclimation. This reflects constraints on changes to peripheral circulation and maximum body temperature. Heat dissipation capacity from the head region increased with acclimation time in the hot treatment, perhaps because angiogenesis was required to reach peak heat transfer rate. We have shown that zebra finches meet high environmental temperature by heat storage, which saves water and energy, and by peripheral vasodilation in the head, which facilitates dry heat loss. These responses will not exclude the need for evaporative cooling, but will lessen the amount of energy expend on body temperature reduction in hot environments.
31.	Sørensen, Jesper Givskov, et al. (author) Expression of thermal tolerance genes in two Drosophila species with different acclimation capacities 2019 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 84, s. 200-207 Journal article (peer-reviewed)abstract Heat tolerance increases at higher acclimation temperatures in D. melanogaster, but not in D. subobscura. The two species represent separate lineages of the subgenus Sophophora of Drosophila with contrasting tropical African and temperate Palearctic evolutionary histories. D. melanogaster has five copies of the inducible hsp70 gene distributed in two clusters, named A (with two copies) and B (three copies), while D. subobscura has only two copies arranged similarly to cluster A of D. melanogaster. The hsp70s of the two species also differ in their cis-regulatory regions, with D. melanogaster exhibiting features of a faster and more productive promoter. We predicted that the interspecific variation in acclimation capacity of heat tolerance is explained by evolved variation in expression of the major group of heat shock proteins. To test this prediction, we compared basal levels of gene expression at different developmental temperatures within each of the two species. Furthermore, we explored the heat hardening dynamics by measuring the induction of gene expression during a ramping assay. The prediction of a stronger heat shock protein response in D. melanogaster as compared to D. subobscura was confirmed for both long-term acclimation and short-term hardening. For D. melanogaster the upregulation with temperature ramping ranged from less than two fold (hsp26) to 2500 fold (hsp70A) increase. In all cases induction in D. melanogaster exceeded that of D. subobscura homologs. These differences correlate with structural differences in the regulatory regions of hsp70, and might explain differences in acclimation capacity among species. Finally, in D. melanogaster we found an indication of an inverse relationship between basal and induced levels of hsp70A and hsp83 expression, suggesting a divergent role for thermal adaptation of these genes at benign and stressful temperatures, respectively. Summary statement. Drosophila melanogaster and D. subobscura differ in heat shock protein expression levels, likely mediated by evolved differences in promoter regions. This corroborates differences in acclimation capacities between the two species.
32.	Walsh, Benjamin S., et al. (author) Female fruit flies cannot protect stored sperm from high temperature damage 2022 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565 .- 1879-0992. ; 105 Journal article (peer-reviewed)abstract Recently, it has been demonstrated that heat-induced male sterility is likely to shape population persistence as climate change progresses. However, an under-explored possibility is that females may be able to successfully store and preserve sperm at temperatures that sterilise males, which could ameliorate the impact of male infertility on populations. Here, we test whether females from two fruit fly species can protect stored sperm from a high temperature stress. We find that sperm carried by female Drosophila virilis are almost completely sterilised by high temperatures, whereas sperm carried by female Zaprionus indianus show only slightly reduced fertility. Heat-shocked D. virilis females can recover fertility when allowed to remate, suggesting that the delivered heat-shock is damaging stored sperm and not directly damaging females in this species. The temperatures required to reduce fertility of mated females are substantially lower than the temperatures required to damage mature sperm in males, suggesting that females are worse than males at protecting mature sperm. This suggests that female sperm storage is unlikely to ameliorate the impacts of high temperature fertility losses in males, and instead exacerbates fertility costs of high temperatures, representing an important determinant of population persistence during climate change.
33.	Wang, Faming, et al. (author) Development and validity of a universal empirical equation to predict skin surface temperature on thermal manikins 2010 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565. ; 35:4, s. 197-203 Journal article (pop. science, debate, etc.)abstract Clothing evaporative resistance is an important input in thermal comfort models. Thermal manikin tests give the most accurate and reliable evaporative resistance values for clothing. The calculation methods of clothing evaporative resistance require the sweating skin surface temperature (i.e., options 1 and 2). However, prevailing calculation methods of clothing evaporative resistance (i.e., options 3 and 4) are based on the controlled nude manikin surface temperature due to the sensory measurement difficulty. In order to overcome the difficulty of attaching temperature sensors to the wet skin surface and to enhance the calculation accuracy on evaporative resistance, we conducted an intensive skin study on a thermal manikin ‘Tore’. The relationship among the nude manikin surface temperature, the total heat loss and the wet skin surface temperature in three ambient conditions was investigated. A universal empirical equation to predict the wet skin surface temperature of a sweating thermal manikin was developed and validated on the manikin dressed in six different clothing ensembles. The skin surface temperature prediction equation in an ambient temperature range between 25.0 and 34.0 °C is Tsk=34.0–0.0132HL. It is demonstrated that the universal empirical equation is a good alternative to predicting the wet skin surface temperature and facilitates calculating the evaporative resistance of permeable clothing ensembles. Further studies on the validation of the empirical equation on different thermal manikins are needed however.
34.	Zheng, Xiangrong, et al. (author) An epidemiological assessment of the effect of ambient temperature on the incidence of preterm births : Identifying windows of susceptibility during pregnancy 2018 In: Journal of Thermal Biology. - : Elsevier BV. - 0306-4565 .- 1879-0992. ; 74, s. 201-207 Journal article (peer-reviewed)abstract It is well known that exposure to thermal stress during pregnancy can lead to an increased incidence of premature births. However, there is little known regarding window(s) of susceptibility during the course of a pregnancy. We attempted to identify possible windows of susceptibility in a cohort study of 3604 children in Changsha with a hot-summer and cold winter climatic characteristics. We examined the association between PTB and ambient temperature during different timing windows of pregnancy: conception month, three trimesters, birth month and entire pregnancy. We found a U-shaped relation between the prevalence of PTB and mean ambient temperature during pregnancy. Both high and low temperatures were associated with PTB risk, adjusted OR (95% CI) respectively 2.57 (1.98–3.33) and 2.39 (1.93–2.95) for 0.5 °C increase in high temperature range (>18.2°C) and 0.5°C decrease in low temperature range (< 18.2°C). Specifically, PTB was significantly associated with ambient temperature and extreme heat/cold days during conception month and the third trimester. Sensitivity analysis indicated that female fetus were more susceptible to the risk of ambient temperature. Our study indicates that the risk of preterm birth due to high or low temperature may exist early during the conception month.
35.	Zverev, Vitali, et al. (author) Ambient temperatures differently influence colour morphs of the leaf beetle Chrysomela lapponica : roles of thermal melanism and developmental plasticity 2018 In: Journal of Thermal Biology. - : Elsevier. - 0306-4565 .- 1879-0992. ; 74, s. 100-109 Journal article (peer-reviewed)abstract We asked whether ambient temperatures can affect morph frequencies within a subarctic population of thepolymorphic leaf beetle Chrysomela lapponica through thermal melanism and/or developmental plasticity. Bodytemperature increased faster in beetles of dark morph than in beetles of light morph under exposure to artificialirradiation. Dark males ran faster than light males in both field and laboratory experiments, and this differencedecreased with increasing ambient air temperature, from significant at 10 °C to non-significant at 20 °C and26 °C. On cold days (6–14 °C), significantly more dark males than light males were found on their host plants incopula (40.8% and 27.3% respectively); on warm days (15–22 °C) this difference disappeared. Light femalesproduced twice as many eggs as dark females; this difference did not depend on the ambient temperature. Theproportion of dark morphs in the progenies of pairs with one dark parent was twice as high as that in theprogenies of pairs in which both parents were light, and this proportion was greater when larvae developed atlow (10 and 15 °C) than at high (20 and 25 °C) temperatures. We conclude that low temperatures may increasethe frequencies of dark morphs in C. lapponica populations due to both the mating advantages of dark males overlight males and developmental plasticity. Variation in frequencies of low-fecund dark morphs in the population,caused by among-year differences in temperature together with density-dependent selection, may contribute tothe evolutionary dynamics of the colour polymorphism and may influence abundance fluctuations in these leafbeetle populations.

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