从能量运转看农作物高产途径

通过对能量在农作物体内运转过程的分析,在前人研究理想株型的前提下进一步提出外部形态结构应和内部生理生化活力相结合、理想株型应与杂种优势相结合的新的高产思路。

Unidirectional Rotary Tendency of a Wave-Driven Rotor

Ocean waves can directly drive WECs （wave energy converters） to perform two types of motion--reciprocating motion and unidirectional rotary motion. In general, the efficiency of a reciprocating WEC is strongly wave-frequency dependent, whereas the efficiency of a rotary WEC can be somewhat wave-frequency independent. To date, a huge majority of WEC technologies under development in industry belong to the reciprocating class, and only a few WEC concepts fall in the unidirectional rotary class. In the present work, a wave-driven rotor for unidirectional rotary motion was proposed and characterized. A numerical tool has been developed for characterization of the rotor＇s unidirectional rotary tendency. The tool included a wave model and a drag force model. Simple circular tubes were used as blades in a basic rotor design. This basic design demonstrated strong potential for unidirectional rotary motion at a proper rotor submersion level and under various wave conditions. Two improved designs were yielded from the basic design. In one improved design, the original circular tubes were replaced with cylindrical shells of semicircular cross section as new blades. In another design, the semicircular shells were further modified to become one-way foldable. The two improvements significantly enhanced the rotors＇ unidirectional rotary tendency in waves, which has been verified by numerical simulation. Broad ranges of wave parameters and the submersion level have been numerically explored on the two improved rotor designs in conjunction with dimensional analysis.

Hole mobility enhancement in uniaxial stressed Ge dependence on stress and transport direction

Utilizing a six-band k.p valence band calculations that considered a strained perturbation Hamiltonian, uniaxial stress-induced valence band structure parameters for Ge such as band edge energy shift, split, and effective mass were quantitatively evaluated. Based on these valence band parameters, the dependence of hole mobility on uniaxial stress(direction, type, and magnitude) and hole transport direction was theoretical studied. The results show that the hole mobility had a strong dependence on the transport direction and uniaxial stress. The hole mobility enhancement can be found for all transport directions and uniaxial stess configurations, and the hole transport along the [110] direction under the uniaxial [110] compressive stress had the highest mobility compared to other transport directions and stress configurations.

Effect of Yiqihuoxue prescription on myocardial energy metabolism after myocardial infarction via cross talk of liver kinase B1-depen-dent Notch1 and adenosine 5'-monophosphate-activated protein kinase

OBJECTIVE: To investigate the effect of Yiqihuoxue prescription(YQHX) from Traditional Chinese Medicine(TCM) on myocardial glucose and lipid metabolism after myocardial infarction via the cross talk between the liver kinase B1(LKB1)-dependent Notch1 and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK). YQHX was prepared with substances with properties that benefit, to activate blood circulation based on the TCM theory.METHODS: Animal models of myocardial infarction were established by ligating Sprague Dawley rats' left anterior descending coronary arteries. The animals were randomly divided into a myocardial infarction(MI) group, a YQHX group, a perindopril group, a γ-secretase inhibitor, Notch signal inhibitor(DAPT) group, a DAPT+YQHX group and a sham group. The related drugs were administered on the second day after operation, and changes in the relevant indexes were examined on weeks 1 and 4.Changes in cardiac structure and function were examined by echocardiography. The glucose and free fatty acids(FFA) were examined by ELISA. The expression of Notch, LKB1 and AMPK m RNA was examined by a real-time fluorescence quantitative method. The expression of glucose transporter 4(GLUT4), and the expression of total acetyl-Co A carboxylase(ACC) and its phosphorylation were examined by western blotting.RESULTS: Compared with the sham group, the expression of Notch, LKB1 and AMPK m RNA in the MI group was lower. Compared with the MI group, the expression of these m RNAs in the YQHX and perindopril groups was higher, and their expression in the DAPT group was lower. At all time points, the protein expression of GLUT4 and p ACC decreased in the MI group. On week 1, the expression of p ACC protein was higher. In the DAPT group, the expression of p ACC protein decreased. Compared with the YQHX group, the expression of p ACC protein in the DAPT + YQHX group was lower. On week 4,compared with the MI group, the expression of GLUT4 protein in the YQHX group and the perindo-pril group was higher. The expression of GLUT4 protein in the DAPT group decreased. Compared with the YQHX group, the expression of GLUT4 protein in the DAPT+YQHX group was lower. There was no significant difference in the expression of ACC protein between the groups.CONCLUSION: YQHX promoted cross talk between the LKB1-dependent Notch1 and AMPK in myocardial tissue after myocardial infarction. Furthermore,it regulated the glucose and lipid metabolism of cardiomyocytes at different time points, thereby ameliorating the cardiac energy metabolism via different mechanisms and protecting the heart.