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451.
The Duong Huyen Pham Teng Choon Kho Pheng Phang Kean Chern Fong Di Yan Yanting Yin Jun Peng Md Arafat Mahmud Saba Gharibzadeh Bahram Abdollahi Nejand Ihteaz M. Hossain Motiur Rahman Khan Naeimeh Mozaffari YiLiang Wu Heping Shen Jianghui Zheng Haoxin Mai Wensheng Liang Chris Samundsett Matthew Stocks Keith McIntosh Gunther G. Andersson Uli Lemmer Bryce S. Richards Ulrich W. Paetzold Anita Ho‐Ballie Yun Liu Daniel Macdonald Andrew Blakers Jennifer Wong‐Leung Thomas White Klaus Weber Kylie Catchpole 《Liver Transplantation》2020,10(9)
Mixed‐dimensional perovskite solar cells combining 3D and 2D perovskites have recently attracted wide interest owing to improved device efficiency and stability. Yet, it remains unclear which method of combining 3D and 2D perovskites works best to obtain a mixed‐dimensional system with the advantages of both types. To address this, different strategies of combining 2D perovskites with a 3D perovskite are investigated, namely surface coating and bulk incorporation. It is found that through surface coating with different aliphatic alkylammonium bulky cations, a Ruddlesden–Popper “quasi‐2D” perovskite phase is formed on the surface of the 3D perovskite that passivates the surface defects and significantly improves the device performance. In contrast, incorporating those bulky cations into the bulk induces the formation of the pure 2D perovskite phase throughout the bulk of the 3D perovskite, which negatively affects the crystallinity and electronic structure of the 3D perovskite framework and reduces the device performance. Using the surface‐coating strategy with n‐butylammonium bromide to fabricate semitransparent perovskite cells and combining with silicon cells in four‐terminal tandem configuration, 27.7% tandem efficiency with interdigitated back contact silicon bottom cells (size‐unmatched) and 26.2% with passivated emitter with rear locally diffused silicon bottom cells is achieved in a 1 cm2 size‐matched tandem. 相似文献
452.
Sodium-23 Nuclear Magnetic Resonance relaxation spectroscopy has been used to investigate the state of intracellular Na+ in control and CCl4-treated rat livers. The analysis of spin-lattice relaxation rates at 1.88 and 7.07 Tesla based on a two-site exchange model led to estimates of pertinent modulation times. Also it has been found that a relatively high quantity of Na+ (PB = 1.59 x 10(-2)) is bound to charged sites of intracellular macromolecules or membranes. The degree of binding strongly decreases in CCl4 treated rat livers. 相似文献
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Kiran Nazeer Nasira Munawar Lone Shumaila Sadique Sikandar Sultan Amna Zia Eupash Saba Riaz 《Saudi Journal of Biological Sciences》2021,28(6):3483-3489
BackgroundPolymorphism in the angiotensin-converting enzyme gene (ACE) is responsible for elevated ACE concentrations in plasma. High ACE levels induce insulin resistance and hyperandrogenism, which are the main attributes of polycystic ovary syndrome (PCOS). Therefore, it was hypothesized that I/D polymorphism plays a role in the pathogenesis of PCOS.ObjectiveA case-control study was designed to investigate the association of I/D polymorphism of the ACE gene with PCOS in Pakistani women of reproductive age.MethodsACE I/D polymorphism was assessed in 252 women of age group 16–40 years. For genotypic analysis, PCR amplification of genomic DNA was carried out. Statistical analysis was performed to interpret the results using SPSS software.ResultsOur study showed that PCOS women were more likely to have a high body mass index and waist circumferences. Most PCOS patients had menstrual irregularities 99.3%, hirsutism 75.2% and cysts in ovaries 66.6%, along with other hyperandrogenic conditions (P-value = 0.001). The genotypic and allelic frequencies were significantly different between patients and controls. There was a significant association of three genotypes with the ratio of LH: FSH among PCOS patients (P = 0.05). Anthropometric characters, comorbidities, clinical symptoms, and PCOS conditions showed no statistical significance with ACE polymorphism.ConclusionsACE I/D polymorphism was not found associated with clinical conditions of PCOS in women of reproductive age. However, it was associated with atypical steroidogenesis. So, it indicates that ACE I/D polymorphism aggravates the pathogenesis of PCOS. 相似文献
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