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With the widespread use of distributed photovoltaic large-scale power generation, the net load ′duck′ curve has become more apparent. However, electric vehicle charging during the day is unable to fully utilize the new energy, and charging at night only adds to the already existing load peak. To address the issue of net load ′peak-to-peak′ exacerbation, the charging load transfer process is facililated with the objective of minimizing the peak-valley difference of net load. To achieve this, statistical data on fast and slow charging behaviors are used to predict future charging load distribution through Monte Carlo simulations. Fast and slow charging load constraints are then established based on the network access characteristics of slow charging and the delayed charging characteristics of fast charging. Then, the load transfer rate is calculated using the gradient descent method, and the charging load price response model is constructed based on user consumption psychology. Finally, economic analysis of power grid peak shaving limits the constraint of electricity price change, and a charging guidance model is constructed with the goal of minimizing the peak-valley difference of net load. Deep reinforcement learning is used to solve the model and solution strategy. The simulation results show that the proposed model and solution strategy can effectively guide the charging load to avoid the peak period of the net load, determine a reasonable price, and reduce the peak-valley difference of the power grid.

To provide a theoretical basis and technical support for the high-yield and high-efficiency production of wheat, we examined the effects of different tillage patterns on wheat grain yield of Jimai 22 and the physiological mechanisms in an experiment with three treatments: 14 years in rotary tillage (R), minimal and no tillage (S), and minimal and no tillage with a 2-year subsoiling interval (SS). We assessed the light interception by wheat plant canopy, the distribution of photosynthate transport, and grain yield for the three cultivation modes. The results showed that leaf area index was significantly higher for SS treatment than the other treatments at 14-28 days after anthesis. The interception rate and amount of photosynthetically active radiation in the upper and middle layers of wheat canopy were significantly higher for SS treatment than R and S treatments at 21 days after anthesis. The contribution rate of grain assimilation and the distribution proportion of 13C assimilated in grain, and the maximum and average filling rates, were the highest under SS treatment. The 1000-kernel weight for SS treatment increased by 8.7% and 9.6%, and the grain yield increased by 14.2% and 19.4% compared with R and S treatments, respectively. SS treatment significantly improved light energy utilization by wheat canopy, promoted the accumulation and transport of dry matter, increased the grain-filling rate, increased grain weight, which together contributed to the highest grain yield. Therefore, SS was the optimal tillage pattern under the conditions of this experiment. [ABSTRACT FROM AUTHOR]

The juntu fish-scale registers of Xiuning County, Huizhou, which were compiled in the seventh year of the Sunzhi reign, were still in use in the Republican period. It took the Tu as a unit, on the opening page it totaled the number of the Tu and it marked their four boundaries. The changes of the four boundaries reflected the partial adjustments of people and land in the Lijia in the early Qing. An examination of these registers reveals that land ownership was relatively decentralized and that the leaders of the Lijia did not possess too much land, 15% of owners were absentees, and 11.35% of the land had permanent tenancy rights but no ownership rights, and ponds were also registered. After the compilation of juntu in the reign of Shunzhi the regional administration of Huizhou was stable. The primary organization Tu in the Ming and Qing dynasties revealed that the distribution of land and the ownership of land did not always exactly coincide with the population in Lijia. From the Qing Dynasty to the Republican period, the Tu was the unit of cadastre formulation and tax collection. [ABSTRACT FROM AUTHOR]

Three dimensional (3D) printing is considered as an advanced manufacturing technology because of its additive nature. Electron beam melting (EBM) is a widely used 3D printing processes for the manufacturing of metal components. However, the products printed via this process generally contain micro porosities which affect mechanical properties, especially the fatigue property. In this paper, two types of EBM printed samples of the Ti-6Al-4V alloy, one with a round cross section and the other with a triangle cross section, were employed to investigate the existence of porosities using computed tomography (CT). Statistical analyses were conducted on the number, volume, shape, and distribution of pores. The results show that small pores (less than 0.000 2 mm 3 ) account for 80% of all pores in each type of samples. Additionally, to some extent, the shape of sample has influence on the number of micro porosities in EBM made Ti-6Al-4V. The sphericity of the pores is relatively low and is inversely proportional to pore volume. It is found that re-melting on the free surface effectively reduce pore density near the surface. This study may help produce a medical implant with better fatigue resistance.

Objective: To study the expression of PTEN, p53 and epidermal growth factor receptor (EGFR) in the molecular subtypes of breast carcinoma and to evaluate the correlations with triple-negative breast cancer.
, Methods: Immunohistochemical MaxVision(TM) method was used to detect the expression of PTEN, p53, EGFR, estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) in 291 cases of infiltrating ductal carcinoma of breast. 
, Results: The positive expression of PTEN, p53 and EGFR protein in breast carcinoma was 57.0%, 57.0% and 38.5%, respectively, which were significantly different from those in benign breast diseases (P<0.05). The expression of PTEN or EGFR in breast cancer was correlated with tumor size, histological grade, lymph node metastasis, TNM stage, ER and HER2 status (P<0.05); the expression of p53 was correlated with tumor size, histological grade and ER status (P<0.05). The difference of positive expression rates of PTEN, p53 and EGFR protein among different subtypes including luminal A, luminal B (HER2-), luminal B (HER2+), HER2 over-expression and triple-negative was statistically significant (P<0.05). There were close correlations among PTEN, p53 and EGFR in the triple-negative subtype (P<0.05).
, Conclusion: Low expression of PTEN and high expression of EGFR and p53 are observed in triple-negative breast cancer, which may synergistically contribute to the pathogenesis of triple-negative breast cancer.