Metabolomics Profiling of Brassinolide and Abscisic Acid In Response to High Temperature Stress

To determine the effect of abscisic acid (ABA), brassinolide (BR) and ABA+BR on grape quality under high temperature stress (HTS), various metabolites were analyzed. Compared with the control (CK), DL-tryptophan, D-raffinose, geniposidic acid, dodecanedioic acid and polyphenols were found to be higher after ABA treatment. After BR treatment, amino acids and poricoic acid B were higher than in CK. And carbohydrates and amino acids were upregulated after ABA+BR treatment. BR and ABA+BR treatment also induced higher endogenous ABA and epibrassinolide (EBR) contents. In addition, treated grape had higher soluble solid concentrations (SSC) and soluble sugar content, and delayed the degradation of middle lamella and microfibrils. Antioxidant and heat shock related genes were examined, which significantly increased in treated grape. The finding of this study suggested that ABA, BR and ABA+BR are very useful for alleviating high temperature damage by increasing the accumulation of osmotic adjustment substances, and endogenous hormones content.

Joint transcriptomic and metabolomic analysis reveals the mechanism of low-temperature tolerance in Hosta ventricosa

Hosta ventricosa is a robust ornamental perennial plant that can tolerate low temperatures, and which is widely used in urban landscaping design in Northeast China. However, the mechanism of cold-stress tolerance in this species is unclear. A combination of transcriptomic and metabolomic analysis was used to explore the mechanism of low-temperature tolerance in H. ventricosa. A total of 12 059 differentially expressed genes and 131 differentially expressed metabolites were obtained, which were mainly concentrated in the signal transduction and phenylpropanoid metabolic pathways. In the process of low-temperature signal transduction, possibly by transmitting Ca2+ inside and outside the cell through the ion channels on the three cell membranes of COLD, CNGCs and CRLK, H. ventricosa senses temperature changes and stimulates SCRM to combine with DREB through the MAPK signal pathway and Ca2+ signal sensors such as CBL, thus strengthening its low-temperature resistance. The pathways of phenylpropanoid and flavonoid metabolism represent the main mechanism of low-temperature tolerance in this species. The plant protects itself from low-temperature damage by increasing its content of genistein, scopolentin and scopolin. It is speculated that H. ventricosa can also adjust the content ratio of sinapyl alcohol and coniferyl alcohol and thereby alter the morphological structure of its cell walls and so increase its resistance to low temperatures.When subjected to low-temperature stress, H. ventricosa perceives temperature changes via COLD, CNGCs and CRLK, and protection from low-temperature damage is achieved by an increase in the levels of genistein, scopolentin and scopolin through the pathways of phenylpropanoid biosynthesis and flavonoid biosynthesis.

Female fruit flies cannot protect stored sperm from high temperature damage

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 destroying 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 destroy 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.

A Study of Skin Thermal Responds of Tonification And Sedation In Moxibustion Using A Mathematical Method

Background: To research the thermomechanical behavior of skin tissue in tonification and sedation of direct moxibustion.Methods: A mathematical method was used to study the thermal responses by skin tissue to tonification and sedation of direct moxibustion. Using a standardized method to measure the temperature of a burning barley (Hordeum vulgare var.) moxa cone, the temperature, burn damage, and thermal stress distributions in the skin tissue were analyzed.Results: According to the ideal skin layers and properties of skin-tissue layers, as well as one measured data, the distribution values of temperature, damage, and stress in the skin tissue with respect to tonification and sedation of direct moxibustion was demonstrated. Conclusion: The thermal responds generated by sedation of direct moxibustion is much larger than those by tonification of direct moxibustion.

Low Temperature Stress Mediates the Antioxidants Pool and Chlorophyll Fluorescence in Vitis vinifera L. Cultivars

Grapes are sensitive to early autumn and spring low temperature damage. The current study aimed to assay the effects of cold stress (+1 °C for 4, 8, and 16 h) on three grapevine cultivars (Ghiziluzum, Khalili, and Perllete). The results showed that cold stress caused significant changes in the antioxidant and biochemicals content in the studied cultivars. Furthermore, examining the chlorophyll fluorescence indices, cold stress caused a significant increase in minimal fluorescence (F0), a decrease in maximal fluorescence (Fm), and the maximum photochemical quantum yield of photosystem II (Fv/Fm) in all cultivars. Among the studied cultivars, ‘Perllete’ had the highest increase in proline content and activity of antioxidant enzymes and also had the lowest accumulation of malondialdehyde, hydrogen peroxide, electrolyte leakage, and F0, as well as less of a decrease in Fm and Fv/Fm, and had a higher tolerance to cold stress than ‘Ghiziluzum’ and ‘Khalili’. ‘Perllete’ and ‘Ghiziluzum’ showed reasonable tolerance to the low temperature stress. ‘Khalili’ was sensitive to the stress. The rapid screening of grapevine cultivars in early spring low temperatures is applicable with the assaying of some biomolecules and chlorophyll fluorescence.

Impact of Die Radius in a Streamlined Die during Wire Drawing

The effects of die radius in a streamlined die on design factors, such as the distribution of strain, stress, temperature, damage, and drawing force of a wire, were investigated during wire drawing for a better understanding of streamlined die and improvement in drawing quality of the wire. A numerical simulation was performed with the die radius of the streamlined die. The behavior of the design factors of the drawn wire fabricated by the streamlined die was different from that of the conventional die and was highly dependent on the die radius. The different behaviors of the design factors with the die radius can be explained by the frictional work and redundant work of the wire with die angle. The temperature rise and drawing force were high at a greater die radius because of the great frictional stress and heating effect stemming from the high contact length of the wire and die. Meanwhile, the higher redundant work at the surface area with decreasing die radius led to higher strain inhomogeneity, effective stress, damage value, temperature rise, and drawing force due to the abrupt change in the metal flow of the wire stemming from the high die angle. After the optimization of several design factors with die radius, it was concluded that the optimum IDR values ranged from 0.14 to 0.18, indicating that a streamlined die with a radius of 70 to 90 mm was the most suitable in the present process condition. In particular, the damage value of the wire was reduced in this range of die radii compared to the conventional die.

Joint Transcriptomic and Metabolomic Analysis Reveals the Mechanism of Low Temperature Tolerance in Hosta Ventricosa

Background: Hosta ventricosa is a robust ornamental perennial plant that can tolerate low temperatures, and which is widely used in urban landscaping design in Northeast China. However, the mechanism of cold stress tolerance in this species is unclear. Methods:This study used a combination of transcriptomic and metabolomic analysis to explore the mechanism of low temperature tolerance in H. ventricosa.Results: A total of 12 059 differentially expressed genes (DEGs) and 131 differentially expressed metabolites were obtained, which were mainly concentrated in the signal transduction and phenylpropanoid metabolic pathways. In the process of low temperature signal transduction, H. ventricosa is mainly through the ion channels on the three cell membranes of COLD, CNGCs and CRLK to transmit Ca2+ inside and outside the cell to sense temperature changes, and stimulate SCRM to combine with DREB through the MAPK signal pathway and Ca2+ signal sensors such as CBL. Strengthen the low temperature resistance of H. ventricosa. The pathways of phenylpropanoid and flavonoid metabolism represent the main mechanism of low temperature tolerance in this species. The plant protects itself from low temperature damage by increasing its content of genistein, scopolentin and scopolin. It is speculated that H. ventricosa can also adjust the content ratio of sinapyl alcohol and coniferyl alcohol and thereby alter the morphological structure of its cell walls and so increase its resistance to low temperatures.Conclusions: In H. ventricosa that is subjected to low temperature stress, temperature changes are perceived through COLD, CNGCs and CRLK, and protection from low temperature damage is achieved by an increase in the levels of genistein, scopolentin and scopolin through the pathways of phenylpropanoid biosynthesis and flavonoid biosynthesis.