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The pollution of soil with heavy metals is an increasingly serious worldwide problem, and cadmium (Cd) has attracted attention because of its high toxicity to almost all plants. Since castor tolerates the accumulation of heavy metals, it has the potential for heavy metal soil remediation. We studied the mechanism of the tolerance of castor to Cd stress treatments at three doses: 300 mg/L, 700 mg/L, and 1,000 mg/L. This research provides new ideas for revealing the defense and detoxification mechanisms of Cd-stressed castor. By combining the results of physiology, differential proteomics and comparative metabolomics, we conducted a comprehensive analysis of the networks that regulate the response of castor to Cd stress. The physiological results mainly emphasize the super-sensitive responses of castor plant roots to Cd stress and the effects of Cd stress on plants’ antioxidant system, ATP synthesis and ion homeostasis. We confirmed these results at the protein and metabolite levels. In addition, proteomics and metabolomics indicated that under Cd stress, the expressions of proteins involved in defense and detoxification, energy metabolism and other metabolites such as organic acids and flavonoids were significantly up-regulated. At the same time, proteomics and metabolomics also show that castor plants mainly block the root system’s absorption of Cd2+ by enhancing the strength of the cell wall, and inducing programmed cell death in response to the three different doses of Cd stress. In addition, the plasma membrane ATPase encoding gene (RcHA4), which was significantly upregulated in our differential proteomics and RT-qPCR studies, was transgenically overexpressed in wild type Arabidopsis thaliana for functional verification. The results indicated that this gene plays an important role in improving plant Cd tolerance.

With the rapid development of hydrogen production technology by using solar energy, the research of Solid Oxide Electrolysis Cell (SOEC) and Photovoltaic/Thermal (PV/T) system have become popular. A design scheme of hydrogen production system based on PV/T technology was proposed. The electrolytic cell combined photovoltaic panels, trough solar collectors and multiple heat exchagers to improve the overall efficiency of the hydrogen production system. The efficiency was predicted based on empirical models. The results showed that the hydrogen production efficiency of SOEC increased with increasing temperature and with decreasing current density. However, the balance between energy efficiency and hydrogen production rate of SOEC needed to be taken into account. The predicted hydrogen production efficiency of SOEC and overall system efficiency also agreed well with the results available in literature.

The high-power wireless charging system for the electric vehicle (EV) generates irreversible magnetic loss and quantities of heat during the charging process. Using thermal management with phase change material (PCM) can reduce the temperature rising rate and ensure the operation safety. A thermal management optimization for a 6.6 kW wireless EV charging system with PCMs was studied. The mathematical model of the heat transfer process in the charging system with thermal management was developed. It was solved by a MATLAB procedure and verified by an experimental measurement. A concept of effective time was proposed as the optimization index to evaluate the performance of the thermal management system. The results indicated that the thermal conductivity of the PCM needed to be improved for a better thermal performance. The modified PCM as paraffin with expanded graphite (EG) was adopted and the optimum thickness and thermal properties were obtained. The effective time by using the optimal PCM layer was 3 and 1.2 times that by using the original PCM layer for the charging system with 5% and 10% energy loss, respectively. The optimal layer can keep the temperature of the charging system below 60 °C in long-term operation.

Exogenous melatonin (MT) regulates plant growth and mitigates stress in response to stress. To analyze the machinery of exogenous melatonin, which improves salt and alkaline tolerance in oats, MT's function was identified in the oat seed germination stage in our previous study. In this study, morphogenesis, photosynthetic physiology, hormone levels, and ion homeostasis were evaluated using the same MT treatment concentration. The results revealed that compared to the S45 treatment, the 100 μmol·L−1 MT treatment efficiently increased the seedling height and main root length of oat seedlings; promoted secondary root development; enhanced the root volume and root surface area; maintained a higher photosynthetic pigment content (carotenoids; chlorophyll a; chlorophyll b); raised the leaf photosynthetic rate (Pn), intercellular CO2 concentration (Ci), conductance to H2O (Gs), and transpiration rate (Tr); enhanced the light energy absorption and conversion of leaves; increased the leaf GA3, Tryptamine (TAM), and IAA contents; and decreased ABA levels. Hierarchical cluster analysis revealed that MT treatment also increased the contents of P, K, Ca, Mn, Cu, Mg, Fe, Zn, Mo, Cd, Al, Se, Ni, Co, and Ti; decreased the Na/K ratio; and maintained cellular ionic homeostasis in oat seedlings under saline–alkali stress, as compared with the untreated group. These findings showed that MT treatment enhanced the adaptation of oat to saline–alkali stress through regulating the physiological process of seedling growth. This suggests that MT plays a different role in improving saline–alkali tolerance in the germination and seedling stages of oat. [ABSTRACT FROM AUTHOR]

BACKGROUND: A high-intensity eccentric exercise may lead to skeletal muscle damage, endoplasmic reticulum stress, increasing misfolded proteins. Aggraphagy works as an effective way of controlling quality of proteins and plays an important role in damage repair. OBJECTIVE: To discover the activation degree of aggrephagy in the damage repair process after an overload eccentric exercise, and to discuss the role of aggrephagy in the exercise-induced muscle damage, which is supplementary to the protein degradation pathway in skeletal muscle damage. METHODS: Sixty-four male adult Sprague Dawley rats were randomly divided into a static control group (n=8) and seven exercise groups according to post-exercise time (0, 3, 6, 12, 24,48 and 72 hours, eight rats in each). Damage models were established by downhill running (-16°, 16m/min, 90 minutes). Subsequently, the histological changes of the rat soleus muscle was observed under an electron microscope and protein expressions of histone deacetylase 6 and microtubule-associated protein 1 light chain 3II/I related to aggrephagy were detected using western bot assay. RESULTS AND CONCLUSION: (1) Under the transmission electron microscope, the rat soleus muscle was disordered and widened and appeared to have transient sarcomere, the Z line was water wave-like, broken and disappeared, and the mitochondria were swollen and unevenly distributed with an unclear structure after high-intensity eccentric exercise. The model rats suffered severest muscle damage at 12 hours and recovered completely at 72 hours after high-intensity eccentric exercise. (2) After one-time eccentric exercise, the expression of histone deacetylase 6 had a transient increase. The histone deacetylase 6 expression reached the peak at 6 hours, then gradually reduced and recovered at 72 hours after exercise. The microtubule-associated protein 1 light chain 3II/I expression was significantly increased at 3 hours after exercise, reached the peak at 12 hours, then reduced significantly and recovered at 72 hours after exercise. All these findings indicate that aggrephagy transiently happens and exerts important roles in the clearance of misfolded proteins, maintenance of cellular environmental homeostasis and recovery of skeletal muscle damage. [ABSTRACT FROM AUTHOR]