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41.
Qi Li Yao Zhao Wenke Zhou Zhengyuan Han Rui Fu Fang Lin Dapeng Yu Qing Zhao 《Liver Transplantation》2019,9(46)
The performance of perovskite solar cells (PSCs) relies on the synthesis method and chemical composition of the perovskite materials. So far, PSCs that have adopted two‐step sequential deposited perovskite with the state‐of‐art composition (FAPbI3)1?x(MAPbBr3)x (x < 0.05) have achieved record power conversion efficiency (PCE), while their one‐step antisolvent dripping counterparts with typical composition Cs0.05FA0.81MA0.14Pb(I0.85Br0.15)3 with more bromine have exhibited much better long‐term operational stability. Thus, halogen engineering that aims to elevate bromine content in sequential deposited perovskite film would push operational stability of PSCs toward that of antisolvent dripping deposited perovskite materials. Here, a Br‐rich seeding growth method is devised and perovskite seed solution with high bromine content is introduced into a PbI2 precursor, leading to bromine incorporation in the resulting perovskite film. Photovoltaic devices fabricated by Br‐rich seeding growth method exhibit a PCE of 21.5%, similar to 21.6% for PSCs having lower bromine content. Whereas, the operational stability of PSCs with higher bromine content is significantly enhanced, with over 80% of initial PCE retained after 500 h tracking at maximum power point under 1‐sun illumination. This work highlights the vital importance of halogen composition for the operational stability of PSCs, and introduces an effective way to incorporate bromine into mixed‐cation‐halide perovskite film via sequential deposition method. 相似文献
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Summary Presented here are techniques developed to culture and analyze three-dimensional (3-D) adipose-like tissues as a means to
bridge the gap between current liminations in culturing preadipocytes (PAs) and that of providing clinically relevant volumes
of adipose tissue useful for soft tissue engineering stratgies in reconstructive surgery. Pilot studies were performed to
determine techniques to visualize and analyze 3-D PA-like tissues as well as to develop successful strategies to culture 3T3-L1
cells in a high aspect ratio vessel rotating-wall bioreactor both with and without microcarriers. Next, a series of cultures
were accessed to verify these techniques as well as to compare the culture of the cells with and without microcarriers. Finally,
a perfused rotating-wall bioreactor was used to further investigate the nature of the aggregates or tissues being generated.
The aggregates that formed in the perfused system were analyzed via histology and in vivo animal studies. PA-like tissues
as large as 4–5 mm in diameter without microcarriers that were capable of lipid-loading and composed of viable cells were
achieved. We have successfully demonstrated that large tissue aggregates can be grown in bioreactor culture systems. 相似文献
44.
Drewitz M Helbling M Fried N Bieri M Moritz W Lichtenberg J Kelm JM 《Biotechnology journal》2011,6(12):1488-1496
Although the relevance of three-dimensional (3-D) culture has been recognized for years and exploited at an academic level, its translation to industrial applications has been slow. The development of reliable high-throughput technologies is clearly a prerequisite for the industrial implementation of 3-D models. In this study the robustness of spherical microtissue production and drug testing in a 96-well hanging-drop multiwell plate format was assessed on a standard 96-well channel robotic platform. Microtissue models derived from six different cell lines were produced and characterized according to their growth profile and morphology displaying high-density tissue-like reformation and growth over at least 15 days. The colon cancer cell line HCT116 was chosen as a model to assess microtissue-based assay reproducibility. Within three individual production batches the size variations of the produced microtissues were below 5%. Reliability of the microtissue-based assay was tested using two reference compounds, staurosporine and chlorambucil. In four independent drug testings the calculated IC(50) values were benchmarked against 2-D multiwell testings displaying similar consistency. The technology presented here for the automated production of a variety of microtissues for efficacy testing in a standard 96-well format will aid the implementation of more organotypic models at an early time point in the drug discovery process. 相似文献
45.
Nina S. Ponomarenko Antony R. Marino Agnes Ostafin Edward J. Bylina James R. Norris Jr. 《生物化学与生物物理学报:生物膜》2009,1788(9):1822-1831
Heterodimer mutant reaction centers (RCs) of Blastochloris viridis were crystallized using microfluidic technology. In this mutant, a leucine residue replaced the histidine residue which had acted as a fifth ligand to the bacteriochlorophyll (BChl) of the primary electron donor dimer M site (HisM200). With the loss of the histidine-coordinated Mg, one bacteriochlorophyll of the special pair was converted into a bacteriopheophytin (BPhe), and the primary donor became a heterodimer supermolecule. The crystals had dimensions 400 × 100 × 100 μm, belonged to space group P43212, and were isomorphous to the ones reported earlier for the wild type (WT) strain. The structure was solved to a 2.5 Å resolution limit. Electron-density maps confirmed the replacement of the histidine residue and the absence of Mg. Structural changes in the heterodimer mutant RC relative to the WT included the absence of the water molecule that is typically positioned between the M side of the primary donor and the accessory BChl, a slight shift in the position of amino acids surrounding the site of the mutation, and the rotation of the M194 phenylalanine. The cytochrome subunit was anchored similarly as in the WT and had no detectable changes in its overall position. The highly conserved tyrosine L162, located between the primary donor and the highest potential heme C380, revealed only a minor deviation of its hydroxyl group. Concomitantly to modification of the BChl molecule, the redox potential of the heterodimer primary donor increased relative to that of the WT organism (772 mV vs. 517 mV). The availability of this heterodimer mutant and its crystal structure provides opportunities for investigating changes in light-induced electron transfer that reflect differences in redox cascades. 相似文献
46.
Promoting extracellular matrix remodeling via ascorbic acid enhances the survival of primary ovarian follicles encapsulated in alginate hydrogels 下载免费PDF全文
47.
Breaking the 10% Efficiency Barrier in Organic Photovoltaics: Morphology and Device Optimization of Well‐Known PBDTTT Polymers 下载免费PDF全文
With the advances in organic photovoltaics (OPVs), the invention of model polymers with superior properties and wide applicability is of vital importance to both the academic and industrial communities. The recent inspiring advances in OPV research have included the emergence of poly(benzodithiophene‐co‐thieno[3,4‐b]thiophene) (PBDTTT)‐based materials. Through the combined efforts on PBDTTT polymers, over 10% efficiencies have been realized recently in various types of OPV devices. This review attempts to critically summarize the recent advances with respect to five well‐known PBDTTT polymers and their design considerations, basic properties, photovoltaic performance, as well as device application in conventional, inverted, tandem solar cells. These PBDTTT polymers also make great contributions to the rapid advances in the field of emerging ternary blends and fullerene‐free OPVs with top performances. Addtionally, new challenges in developing novel photovoltaic polymers with more superior properties are prospected. More importantly, the research of highly efficient PBDTTT‐based polymers provides useful insights and builds fundamentals for new types of OPV applications with various architectures. 相似文献
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Entomopathogenic fungi, such as Beauveria bassiana and Metarhizium anisopliae, are environmentally friendly biocontrol agents (BCAs) against various arthropod pests. We provide an overview to the past-decade advances in fungal BCA research and application in China. Since 1960s, fungal BCAs have been mass-produced for application and at present, thousands of tons of their formulations are annually applied to control forest, agricultural, greenhouse and grassland insect pests throughout the country. Apart from technical advances in mass production, formulation and application of fungal BCAs, basic studies on the genomics, molecular biology, genetic engineering and population genetics of fungal entomopathogens have rapidly progressed in the past few years in China. The completed genomic studies of M. anisopliae, Metarhizium acridum, B. bassiana and Cordyceps militaris provide profound insights into crucial gene functions, fungal pathogenesis, host–pathogen interactions and mechanisms involved in fungal sexuality. New knowledge gained from the basic studies has been applied to improve fungal virulence and stress tolerance for developing more efficacious and field-persistent mycoinsecticides by means of microbial biotechnology, such as genetic engineering. To alleviate environmental safety concerns, more efforts are needed to generate new data not only on the effects of engineered BCAs on target and non-target arthropods but also on their potential effects on gene flow and genetic recombination before field release. 相似文献