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The authors investigated the role of thermoregulation mechanisms and thermal limits on thermal niche differentiation in two hierarchical similar Eucraniini dung beetle assemblages inhabiting arid environments in north‐western Argentina. Both dung beetle assemblages showed temporal and thermal niche segregation between all sympatric species, minimising overlap during their daily activity and soil temperature preferences.Thermal tolerance of Eucraniini species was partially modulated by behavioural adaptations and complementary thermoregulatory mechanisms related to eliminating the temperature excess, increasing the metabolic rate promoting an effective regulation of the excess heat that permitted a decrease in their body temperature by evaporative cooling. Based on the physiological syndromes obtained, the authors found a greatest interspecific differentiation that allows us to differentiate each species using ecophysiological traits. Interspecific body size differences in sympatric Eucraniini contributed greatly to the metabolic capacity of individuals to thermoregulate.Eucranium species, the largest species showed the lowest capacity to respond to thermal stress decreasing heat excess temperature, presenting the lowest thermal limit values coinciding with a 'minithermy' strategy that explains the preferred lower soil temperatures around 30°C. On the contrary, Anomiopsoides species showed a clear adaptation to being active during periods of the day in which the soil temperature reached over 50°C, adopting a strategy of 'maxithermy' by foraging when temperatures are closer to their thermal limits.In conclusion, it can be determined that ecophysiological syndromes related to thermal stress regulation and thermal limits allowed a displacement in thermal niche dimension, minimising interspecific competition and so allowing species coexistence in Eucraniini dung beetles. [ABSTRACT FROM AUTHOR]

This work analyzed the physical, chemical, and thermal properties of sorghum flour and the relationships among these, in order to evaluate its suitability for the development of food products. Sorghum flour was obtained through roller dry milling from 20 commercial hybrids grown in Argentina with the average chemical composition of the samples being: 0.68% ash, 3.67% fat, 12.21% protein, 83.45% total carbohydrates, 79.77% starch (amylose 26.6%), and 34.9 mg of tannic acid per 100 g of flour. A high degree of variability among evaluated properties was found, particularly in the pasting properties peak viscosity (2809-5184 mPa/s), breakdown (1169-3170 mPa/s), and final viscosity (3030-4401 mPa/s) with onset temperature ( To) and gelatinization enthalpy (Δ H) varying between 66.8 and 72.6°C, and 5.38 and 8.48 J/g, respectively. A principal component analysis demonstrated that the grain color did not influence the chemical composition of the flour. Cluster analysis permitted the separation of flour into three different groups with different thermal and physicochemical characteristics, and enabled the selection of hybrids. Thus, sorghum flour is a versatile ingredient and can be used in several food and non-food applications. [ABSTRACT FROM AUTHOR]

The physicochemical properties of starches of 16 Andean potato genotypes from the Quebrada de Humahuaca, Jujuy, are studied and possible applications are evaluated. Moisture, protein, ash, phosphorus, amylose/amylopectin ratio, particle size, swelling power, water absorption index, solubility index, syneresis, turbidity, thermal properties, gelatinization, retrogradation, and their corresponding enthalpies are determined. The analysis of principal components allowed obtaining groups of varieties with similar properties. Four groups of genotypes are obtained: one group is characterized by high gelatinization temperatures, so it can be used for products that require high processing temperatures; the second, with greater swelling power, can be applied in products that require water retention; other can be used in the production of edible film because it has higher amylose content which improves its mechanical properties; the latter is characterized by having a high stability and lower syneresis which indicates it is possible to use in processes that require refrigeration and freezing. The information obtained in this study can be useful for the production of potatoes with differentiated characteristics of their starches and with the possibility to be applied both in food and in non‐food products. [ABSTRACT FROM AUTHOR]