Flexible solar cells based on foldable silicon wafers with blunted edges.

Flexible solar cells have a lot of market potential for application in photovoltaics integrated into buildings and wearable electronics because they are lightweight, shockproof and self-powered. Silicon solar cells have been successfully used in large power plants. However, despite the efforts made for more than 50 years, there has been no notable progress in the development of flexible silicon solar cells because of their rigidity1-4. Here we provide a strategy for fabricating large-scale, foldable silicon wafers and manufacturing flexible solar cells. A textured crystalline silicon wafer always starts to crack at the sharp channels between surface pyramids in the marginal region of the wafer. This fact enabled us to improve the flexibility of silicon wafers by blunting the pyramidal structure in the marginal regions. This edge-blunting technique enables commercial production of large-scale (>240 cm2), high-efficiency (>24%) silicon solar cells that can be rolled similarly to a sheet of paper. The cells retain 100% of their power conversion efficiency after 1,000 side-to-side bending cycles. After being assembled into large (>10,000 cm2) flexible modules, these cells retain 99.62% of their power after thermal cycling between -70 °C and 85 °C for 120 h. Furthermore, they retain 96.03% of their power after 20 min of exposure to air flow when attached to a soft gasbag, which models wind blowing during a violent storm.

In situ performance and stability tests of large-area flexible polymer solar cells in the 35-km stratospheric environment.

Flexible organic solar cells (FOSCs) are one of the most promising power sources for aerospace aircraft due to their attractive advantages with high power-per-weight ratio and excellent mechanical flexibility. Understanding the performance and stability of high-performance FOSCs is essential for the further development of FOSCs for aerospace applications. In this paper, after systematic investigations on the performance of the state-of-the-art high-performance solar cells under thermal cycle and intensive UV irradiation conditions, in situ performance and stability tests of the solar cells in the 35 km stratospheric environment were carried out through a high-altitude balloon uploading. The encapsulated FOSCs with an area of 0.64 cm2 gave the highest power density of 15.26 mW/cm2 and an efficiency over 11%, corresponding to a power-per-weight ratio of over 3.32 kW/kg. More importantly, the cells showed stable power output during the 3-h continuous flight at 35 km and only 10% performance decay after return to the lab, suggesting promising stability of the FOSCs in the stratospheric environment.

Association of GAB2 with Quality of Life and Negative Emotions in Patients with Gastric Cancer after Postoperative Comprehensive Care.

GRB2-associated binding protein 2 (GAB2), a highly conserved scaffold protein, is abnormally expressed and activated in patients with gastric cancer (GC). However, the genetic diversity of GAB2 in GC and its association with the clinical manifestations of patients are still unclear. Here, we explored the polymorphism of GAB2 rs2373115 in GC and its association with quality of life (QOL) and negative emotions of patients with GC after postoperative comprehensive care. A case-control study showed that the frequency of the GG genotype of GAB2 rs2373115 in the GC patients was higher than that in the healthy people, while the frequency of the TT + TG genotype was lower than that in the healthy people. Obvious distinctions were observed in the histological grade and TNM staging between the GG genotype and TT + TG genotype. In addition, SAS and SDS scores in the patients with GG genotype were higher than those in patients with TT + TG genotype, while the emotional function, cognitive function, dyspnea, fatigue, sleep disorder, and overall QOL in patients with GG genotype were lower than those in patients with TT + TG genotype. These results showed that GAB2 rs2373115 polymorphism was related to QOL and negative emotions in patients with GC after postoperative comprehensive care.

[Abnormal expressions of positive cell cycle control factors and thyroid carcinoma occurrence and progression].

OBJECTIVE: To explore the relationship between abnormal expressions of positive cell cycle control factors and thyroid carcinoma occurrence and progression, and assess the value of these factors in evaluating tumor cell proliferation activity and the prognosis of the patients. METHODS: Immunohistochemical SP method was used to detect the expressions of MCM7, CDK2 and Ki-67 proteins in 50 cases of thyroid carcinoma, 30 cases of thyroid adenoma, 30 cases of nodular goiter and 20 cases of normal thyroid gland tissues. RESULTS: The positive rates of MCM7, CDK2 and Ki-67 expressions in thyroid carcinoma were 100% (50/50), 80.00% (40/50) and 84.00% (42/50), significantly higher than the rates in thyroid adenoma, nodular goiter and normal thyroid tissue (P<0.01). In thyroid carcinoma tissues, positive correlations were observed between the expressions of MCM7 and CDK2 proteins (r=0.637, P<0.01), MCM7 and Ki-67 proteins (r=0.633, P<0.01), and CDK2 and Ki-67 proteins (r=0.862, P<0.01). CONCLUSION: The high expressions of MCM7, CDK2 and Ki-67 protein may contribute to the development of thyroid carcinoma, and their combined examination may serve as useful index for early diagnosis and prognostic evaluation of thyroid carcinoma. MCM7 is superior to Ki-67 in the evaluation of the thyroid tumor cell proliferation activity.