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The "efficiency and cost reduction" of large size Czochralski monocrystalline silicon is an urgent problem for photovoltaic enterprises. In this paper, the finite element volume method was used to simulate the growth process of Φ300 mm Czochralski monocrystalline silicon in both steady and unsteady state, respectively, to study the change rule of crystal-melt interface, point defect distribution and growth energy consumption during the growth process of Czochralski monocrystalline silicon by increasing the pulling rate. The results show that the shift of crystal-melt interface is 33 mm when the pulling rate increases to 1. 6 mm/ min, which would not affect the stable growth of crystals. The pulling rate plays a decisive role in the distribution of point defects in the crystal. Increaseing the pulling rate could not only reduce the concentration of self-interstital defects, but also make the V/ G in the crystal bar always higher than the critical value. And the pulling rate has a great influence on the power consumption. After increasing the pulling rate, the crystal growth time is reduced by 46. 4%, and the power consumption for monocrystalline silicon growth is reduced by 4. 97%. Optimization and control of appropriate pulling rate is conducive to low cost growth of specific point defect distribution or even point defect free monocrystalline silicon, which provides some theoretical support for improving the quality of large size Czochralski monocrystalline silicon and reducing production energy consumption. [ABSTRACT FROM AUTHOR]

Greening can usually have a cooling effect on urban space; but is this law also applicable to coastal sloping urban space? The coastal urban space of Qingdao Haizhifeng Square, with a sloping topography, was the area we selected to study. The study area contained two parts: a coastal green space and a residential area. ENVI-met was used to create six scenarios. Different lawns, black pine and ash were planted in the two areas to study the cooling effect. The results showed that the closer the area was to the sea, the better the thermal comfort. In both the coastal green area and the residential area, trees increased the PET of the site, and the higher the LAI of the trees, the more obvious the thermal effect. At 15:00, the hottest time during the summer, the highest PET at pedestrian height was lowest in the scenario without trees, reaching 28.3 °C, and the highest was with full ash, reaching 34.3 °C. At the same time, the average difference in PET between the two scenarios was 1.4 °C. The highest PET at pedestrian height was generated in the area of the building away from the sea breeze, especially in the case of the sloping topography behind it or dense street trees on the urban road. Finally, it was concluded that, in urban spaces with a coastal slope topography, lawns should be planted in the coastal green part and low LAI trees in residential areas, and shade trees should not be planted on the coastal walkway. This afforestation strategy can provide a basis to formulate a strategy for promoting the design of regions with similar geographical and climatic conditions in the future. [ABSTRACT FROM AUTHOR]

Multicast communication involves transmitting information from a single source node to multiple destination nodes, and is becoming an important requirement in high-performance networks. In this paper, we study multicast communication in a class of optical WDM networks with regular topologies such as linear arrays, rings, meshes, tori and hypercubes. For each type of network, we derive the necessary and sufficient conditions on the minimum number of wavelengths required for a WDM network to be wide-sense nonblocking for multicast communication under some commonly used routing algorithms. Index Terms--Multicast communication, optical networks, regular networks, routing algorithm, wavelength assignment algorithm, wavelength division multiplexing (WDM), wide-sense nonblocking.

Polymer hydrolysis polyacrylamide and microbes have been used to enhance oil recovery in many oil reservoirs. However, the application of this two-method combination was less investigated, especially in low permeability reservoirs. In this work, two bacteria, a rhamnolipid-producing Pseudomonas aeruginosa 8D and a lipopeptide-producing Bacillus subtilis S4, were used together with hydrolysis poly-acrylamide in a low permeability heterogeneous core physical model. The results showed that when the two bacterial fermentation liquids were used at a ratio by volumeof 1:3 (v:v), the mixture showed the optimal physicochemical properties for oil-displacement. In addition, the mixture was stable under the conditions of various temperature (20–70 °C) and salinity (0–22%). When the polymer and bacteria were mixed together, it had no significant effects in the viscosity of polymer hydrolysis polyacrylamide and the viability of bacteria. The core oil-displacement test displayed that polymer hydrolysis polyacrylamide addition followed by the bacterial mixture injection could significantly enhance oil recovery. The recovery rate was increased by 15.01% and 10.03%, respectively, compared with the sole polymer hydrolysis polyacrylamide flooding and microbial flooding. Taken together, these results suggest that the strategy of polymer hydrolysis poly-acrylamide addition followed by microbial flooding is beneficial for improving oil recovery in heterogeneous low permeability reservoirs. [ABSTRACT FROM AUTHOR]

Introduction: Esophageal cancer is the fourth most common cause of cancer death in China. Patients with esophageal cancer are more likely to suffer from malnutrition. The purpose of this study is to assess nutritional status of patients with esophageal cancer from multiple perspectives and analyze the risk factors., Methods: A total of 1482 esophageal cancer patients were enrolled in the study. We investigated the Scored Patient Generated Subjective Global Assessment (PG-SGA) scores, NRS-2002 scores, Karnofsky performance status scores, anthropometric, and laboratory indicators of patients. Unconditional logistic regression analysis was applied to identify the risk factors of nutritional status., Results: PG-SGA (≥4) and NRS-2002 (≥3) showed the incidence of malnutrition were 76% and 50%, respectively. In the patients with PG-SGA score ≥4, the proportion of patients who did not receive any nutritional support was 60%. The incidence of malnutrition in females was significantly higher than that in males. Besides, abnormality rates of Red blood cell (P < 0.001), MAC (P = 0.037), and MAMC (P < 0.001) in males was significantly higher than that in females, while abnormality rates of TSF (P < 0.001) was lower than that in females. After adjusted with the other potential risk factors listed, unconditional logistic regression analysis indicated smoking (odds ratio: 2.868, 95% confidence interval: 1.660-4.954), drinking (OR: 1.726, 95% CI: 1.099-2.712), family history (OR: 1.840, 95% CI: 1.132-2.992), radiotherapy or chemotherapy (OR: 1.594, 95% CI: 1.065-2.387), and pathological stage (OR: 2.263, 95% CI: 1.084-4.726) might be the risk factors of nutritional status, while nutritional support can reduce the risk of malnutrition., Conclusion: Effective nutritional risk assessment methods and nutritional intervention measures can be adopted according to the research data to improve quality of life of esophageal cancer patients., (Copyright © 2020. Published by Elsevier Inc.)

Background: The number of cancer patients with diabetes mellitus (DM) is steadily rising. Little is known about the nutritional status of this population. This study characterized the nutritional status and survival of cancer patients with diabetes compared with those without diabetes., Methods: A total of 8247 cancer patients were prospectively enrolled from 72 hospitals in China and followed until August 2019. A global estimation of the nutritional status was performed for each participant using standardized tools. The outcomes were cancer-specific survival (CSS) and overall survival (OS)., Results: The incidence of diabetes was 7.6% in the whole population. In comparison with the non-DM group, the DM group had greater body weight, but a similar fat-free mass, a lower handgrip strength and a decreased Karnofsky performance score. A higher proportion of patients with diabetes were overweight/obese as indicated by BMI. The percentage of patients who were at risk of malnutrition (evaluated by PG-SGA) was higher in the DM group (score ≥ 4, 56.7% vs 52.9%). Patients with DM showed a worse CSS (4-year CSS, 62% vs 73%) and OS (4-year OS 39% vs 52%). Diabetes was associated with an increased risk of both cancer-specific (hazard ratio (HR) = 1.282, 95% confidence interval (CI) 1.070-1.536) and overall (HR = 1.206, 95% CI 1.040-1.399) mortality., Conclusions: Cancer patients with diabetes had a larger body mass but lower muscle strength, poorer performance status and higher incidence of malnourishment. Diabetes was associated with compromised survival. Tailored nutritional intervention is necessary for this subpopulation of patients., (© 2020 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)