Biometeorological Conditions during the August 2015 Mega-Heat Wave and the Summer 2010 Mega-Heat Wave in Ukraine

The human-biometeorological conditions in Ukraine during two mega-heat waves were analyzed. The evaluation is based on physiologically equivalent temperature (PET). The calculation of PET is performed utilizing the RayMan model. The results revealed these two mega-heat waves produced strenuous human-biometeorological conditions on the territory of Ukraine. During the summer 2010 mega-heat wave, strong and extreme heat stress prevailed at about midday at the stations where this atmospheric phenomenon was observed. The mega-heat wave of August 2015 was characterized by a lower heat load. The diurnal variation of PET values during the researched mega-HW was similar to that of the diurnal variation of air temperature with minimum values in the early morning and maximum values in the afternoon. On the territory where mega-heat waves were observed, the number of days during which heat stress occurred for 9 h amounted to 97.6% for the period from 31 July to 12 August 2010 and 77.1% for the mega-heat wave of August 2015.

Temperature adaptations of the thermophilic snail Echinolittorina malaccana: insights from metabolomic analysis

The periwinkle snail Echinolittorina malaccana, whose upper lethal temperature is near 55°C, is one of the most heat-tolerant eukaryotes known. We conducted a multi-level investigation, including cardiac physiology, enzyme activity, and targeted and untargeted metabolomic analysis, that elucidated a spectrum of adaptations to extreme heat. All systems examined showed heat intensity-dependent responses. Under moderate heat stress (from 37 to 45°C) the snail depressed cardiac activity and entered a state of metabolic depression. The global metabolomic analyses and enzymatic analysis showed that the depressed metabolic state under moderate heat stress entailed production of metabolites characteristic of oxygen-independent pathways of ATP generation (lactate and succinate), which suggests that anaerobic metabolism was the main energy supply pathway under heat stress (from 37 to 52°C). The metabolomic analyses also revealed alterations in glycerophospholipid metabolism under extreme heat stress of 52°C, which likely reflected adaptive changes to maintain membrane structure. Small molecular mass organic osmolytes (glycine betaine, choline, and carnitine) showed complex changes in concentration that were consistent with a role of these protein-stabilizing solutes in protection of the proteome under heat stress. This thermophilic species thus can deploy a wide array of adaptive strategies to acclimatize to extremely high temperatures.

The influence of external environment on workers on scaffolding illustrated by UTCI

The aim of the article was to present the influence of the external environment on people working on scaffolding. For this purpose, the heat load of a man was determined using the universal thermal climate index. The research was carried out on 40 facade scaffolds located in four voivodeships in Poland: Lower Silesia, Lublin, Lodzkie, and Masovian. The conducted analysis showed that employees may experience strong or very strong heat stress, and also extreme heat stress in isolated cases. The highest probability at 0.30 level occurs on scaffolds located in the Lodzkie voivodeship. Environmental conditions are therefore unfavourable for people working outside. This can lead to reduced concentration, longer reaction time, and greater fatigue, contributing to an increase in situations that could lead to accidents. Hazard identification allows to take safety measures that improve the comfort of work on scaffolding.

Approaching environmental human thermophysiological thresholds for the case of Ankara, Turkey

The disclosed study undertook a ‘human centred-approach’ that ascertained and categorised environmental human thermophysiological risk factors by relating them to the human biometeorological system through the use of three widely utilised energy balance model (EBM) indices, the physiologically equivalent temperature (PET), the modified PET, and the universal thermal climate index (UTCI). The disclosed assessment was carried out over the past decade (i.e., 2010–2019) with a 3-h temporal resolution for the case of Ankara through two WMO meteorological stations to compare both local urban and peri-urban environmental conditions. The study recognised extreme annual variability of human physiological stress (PS) during the different seasons as a result of the biometeorological processing of the singular variables, which in the case of average PET for both stations, varied by up to 75 °C between the winter and summer for the same annual dataset (2012). In addition, all EBMs indicated higher heat stress within the city centre that were conducive of both urban extreme heatwaves and very hot days during the summer months, with extreme heat stress levels lasting for longer than a week with PET values reaching a maximum of 48 °C. Similar cold extremes were found for the winter months, with PET values reaching − 30 °C, and average PS levels varying lower in the case of the peri-urban station.Graphical abstract

Effect of Heat Stress on Seed Protein Composition and Ultrastructure of Protein Storage Vacuoles in the Cotyledonary Parenchyma Cells of Soybean Genotypes That Are Either Tolerant or Sensitive to Elevated Temperatures

High growth temperatures negatively affect soybean (Glycine max (L.) Merr) yields and seed quality. Soybean plants, heat stressed during seed development, produce seed that exhibit wrinkling, discoloration, poor seed germination, and have an increased potential for incidence of pathogen infection and an overall decrease in economic value. Soybean breeders have identified a heat stress tolerant exotic landrace genotype, which has been used in traditional hybridization to generate experimental genotypes, with improved seed yield and heat tolerance. Here, we have investigated the seed protein composition and ultrastructure of cotyledonary parenchyma cells of soybean genotypes that are either susceptible or tolerant to high growth temperatures. Biochemical analyses of seed proteins isolated from heat-tolerant and heat-sensitive genotypes produced under 28/22 °C (control), 36/24 °C (moderate), and 42/26 °C (extreme) day/night temperatures revealed that the accumulation in soybean seeds of lipoxygenase, the β-subunit of β-conglycinin, sucrose binding protein and Bowman-Birk protease inhibitor were negatively impacted by extreme heat stress in both genotypes, but these effects were less pronounced in the heat-tolerant genotype. Western blot analysis showed elevated accumulation of heat shock proteins (HSP70 and HSP17.6) in both lines in response to elevated temperatures during seed fill. Transmission electron microscopy showed that heat stress caused dramatic structural changes in the storage parenchyma cells. Extreme heat stress disrupted the structure and the membrane integrity of protein storage vacuoles, organelles that accumulate seed storage proteins. The detachment of the plasma membrane from the cell wall (plasmolysis) was commonly observed in the cells of the sensitive line. In contrast, these structural changes were less pronounced in the tolerant genotype, even under extreme heat stress, cells, for the most part, retained their structural integrity. The results of our study demonstrate the contrasting effects of heat stress on the seed protein composition and ultrastructural alterations that contribute to the tolerant genotype’s ability to tolerate high temperatures during seed development.

Emergence of heat stress hazards in the CMIP6 models

<p>Hazards associated with the combined effects of temperature and humidity can have a wide range of impacts, particularly on human health and agriculture. The human body removes metabolic heat through sweating and heat conduction, and the efficiency of these processes is reduced when ambient temperatures and humidity are high, resulting in heat stress. The effects of this range from general discomfort to increased morbidity and mortality rates, trends that have been observed during recent severe heatwaves such as those that occurred during the summer of 2019 in Europe. A number of factors may exacerbate heat stress, including intense physical activity and being located in an urban area as opposed to a rural area.</p><p>As global temperatures increase, the risk associated with heat stress hazards is expected to increase, and this signal is expected to emerge from natural variability over the coming decades, if not sooner. Here, simulations from the new CMIP6 models are analysed to investigate the timing of emergence of heat stress hazards, in order to identify regions of the globe that are particularly vulnerable to extreme heat stress and/or imminent emergence of these hazards. Event attribution techniques are also applied to estimate the impact of anthropogenic warming on the hazard risk.</p>