The trade‐off between the open‐circuit voltage (Voc) and short‐circuit current density (Jsc) has become the core of current organic photovoltaic research, and realizing the minimum energy offsets that can guarantee effective charge generation is strongly desired for high‐performance systems. Herein, a high‐performance ternary solar cell with a power conversion efficiency of over 18% using a large‐bandgap polymer donor, PM6, and a small‐bandgap alloy acceptor containing two structurally similar nonfullerene acceptors (Y6 and AQx‐3) is reported. This system can take full advantage of solar irradiation and forms a favorable morphology. By varying the ratio of the two acceptors, delicate regulation of the energy levels of the alloy acceptor is achieved, thereby affecting the charge dynamics in the devices. The optimal ternary device exhibits more efficient hole transfer and exciton separation than the PM6:AQx‐3‐based system and reduced energy loss compared with the PM6:Y6‐based system, contributing to better performance. Such a “two‐in‐one” alloy strategy, which synergizes two highly compatible acceptors, provides a promising path for boosting the photovoltaic performance of devices.

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This comprehensive prospective analysis suggests women with higher circulating levels of α-carotene, β-carotene, lutein+zeaxanthin, lycopene, and total carotenoids may be at reduced risk of breast cancer.

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The doping mechanisms of N-DMBI-H in n-type organic semiconductors were revealed at the first-principles level.

The authors investigated the association between overweight at the time of or soon after cancer diagnosis and survival in a cohort of 1,455 breast cancer patients aged 25-64 years. The patients were recruited into the Shanghai Breast Cancer Study (Shanghai, China), a population-based case-control study, between August 1996 and March 1998. The median follow-up time for this cohort was 5.1 years (1996-2002) after breast cancer diagnosis, and 240 deaths were identified. Being overweight at cancer diagnosis or soon afterward, as measured by body mass index (BMI; weight (kg)/height (m)(2)), was associated with poorer overall survival and disease-free survival. Five-year survival rates were 86.5%, 83.8%, and 80.1% for subjects whose BMIs were <23.0, 23.0-24.9, and >or=25.0, respectively (p = 0.02); the corresponding 5-year disease-free survival rates were 81.9%, 78.1%, and 76.6% (p = 0.05). The inverse association between BMI and survival persisted after adjustment for age at diagnosis and other known prognostic factors for breast cancer, including disease stage. The authors found neither waist:hip ratio nor waist circumference to be independently associated with overall survival or disease-free survival. These results suggest that excess weight may be an independent predictor of breast cancer survival among Chinese women.

Very few prospective studies have reported previously on the association of micronutrient intake and the risk of cancers of the upper digestive tract (mouth, pharynx, esophagus, and stomach) in western populations. During 7 years of follow-up in the Iowa Women's Health Study, from 1986-1992, 59 of the 34,691 at-risk cohort members developed cancers of the upper digestive tract. The association of retinol and antioxidant vitamins (carotene and vitamins C and E) were evaluated separately for cancers of the mouth/pharynx/esophagus (n = 33) and stomach (n = 26). After adjustment for age, smoking, and total energy intake, higher intakes of carotene and vitamins C and E were related to lower risks of both oral/pharyngeal/esophageal and gastric cancers, while retinol was associated with lower risk of gastric cancer only. The dose-response relation between gastric cancer risk and intake of carotene was clear and statistically significant, with relative risks of 0.6 and 0.3, respectively, observed among women in the upper two versus the lowest tertiles of intake. This study provides further evidence that higher intake of antioxidant vitamins may be important in the prevention of cancers of the upper digestive organs.

Both the efficiency and stability of low-cost organic solar cells are central components for meeting the requirements of commercialization for organic photovoltaics (OPV). Furthermore, the relationship between the chemical structure of an active material and morphology and its effects on efficiency and stability is still largely undetermined. Additionally, both the kinetic and thermodynamic morphology states of an active layer can have a huge impact on efficiency and stability, even when the chemical structures of materials applied in the active layer are especially the same or similar. Here, using two series of acceptor–donor–acceptor (A–D–A)-type small-molecule acceptors (SMAs) with similar backbone structures, we demonstrate the relevance of fine-tuned chemical structures with their solution and solid-state properties, further leading to significantly different behavior in terms of both device efficiency and stability. This is also partially due to the different morphology states caused by such fine chemical structure tuning. Our results indicate that a delicate balance of molecular aggregation and ordered stacking morphology is required to achieve and lead to high efficiency and stability. Thus, among the two series of molecules, UF-EH-2F, with both optimal length and steric hindrance of side chains, achieves the preponderant morphology in its corresponding device, where its morphologies “efficient state” and “stable state” are almost overlapped, and thus lead to both the highest efficiency (power conversion efficiency, PCE = 13.56%) and the best stability. Our results indicate that it is highly possible to achieve the morphology state required for both high efficiency and stability simultaneously by fine-tuning the chemical structure of active materials for organic solar cells.