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951.
Annulated Dialkoxybenzenes as Catholyte Materials for Non‐aqueous Redox Flow Batteries: Achieving High Chemical Stability through Bicyclic Substitution 下载免费PDF全文
Jingjing Zhang Zheng Yang Ilya A. Shkrob Rajeev S. Assary Siu on Tung Benjamin Silcox Wentao Duan Junjie Zhang Chi Cheung Su Bin Hu Baofei Pan Chen Liao Zhengcheng Zhang Wei Wang Larry A. Curtiss Levi T. Thompson Xiaoliang Wei Lu Zhang 《Liver Transplantation》2017,7(21)
1,4‐Dimethoxybenzene derivatives are materials of choice for use as catholytes in non‐aqueous redox flow batteries, as they exhibit high open‐circuit potentials and excellent electrochemical reversibility. However, chemical stability of these materials in their oxidized form needs to be improved. Disubstitution in the arene ring is used to suppress parasitic reactions of their radical cations, but this does not fully prevent ring‐addition reactions. By incorporating bicyclic substitutions and ether chains into the dialkoxybenzenes, a novel catholyte molecule, 9,10‐bis(2‐methoxyethoxy)‐1,2,3,4,5,6,7,8‐octahydro‐1,4:5,8‐dimethanenoanthracene (BODMA), is obtained and exhibits greater solubility and superior chemical stability in the charged state. A hybrid flow cell containing BODMA is operated for 150 charge–discharge cycles with a minimal loss of capacity. 相似文献
952.
Using Ultralow Dosages of Electron Acceptor to Reveal the Early Stage Donor–Acceptor Electronic Interactions in Bulk Heterojunction Blends 下载免费PDF全文
Carr Hoi Yi Ho Sin Hang Cheung Ho‐Wa Li Ka Lok Chiu Yuanhang Cheng Hang Yin Mau Hing Chan Franky So Sai‐Wing Tsang Shu Kong So 《Liver Transplantation》2017,7(12)
Tuning the donor–acceptor (D–A) weight ratio is an essential step to optimize the performance of a bulk heterojunction (BHJ) solar cell. The unoptimized regime with a low acceptor concentration is generally unexplored despite it may reveal the early stage electronic D–A interactions. In this study, PTB7:PC71BM is used to examine factors that limit the device performance in unoptimized regime. The key limiting factor is the creation of traps and localized states originated from fullerene molecules. Photothermal deflection spectroscopy is used to quantify the trap density. Starting with pristine PTB7, addition of small concentration of fullerene increases the electron trap density and lowers the electron mobility. When the D–A weight ratio reaches 1:0.1, fullerene percolation occurs. There is an abrupt drop in trap density and simultaneously a six orders of magnitude increase in the electron mobility. Furthermore, the fill factors of the corresponding photovoltaic devices are found to anticorrelate with the trap density. This study reveals that electron trapping is the key limiting factor for unoptimized BHJ solar cells in low fullerene regime. 相似文献
953.
High Voltage LiNi0.5Mn0.3Co0.2O2/Graphite Cell Cycled at 4.6 V with a FEC/HFDEC‐Based Electrolyte 下载免费PDF全文
Meinan He Chi‐Cheung Su Zhenxing Feng Li Zeng Tianpin Wu Michael J. Bedzyk Paul Fenter Yan Wang Zhengcheng Zhang 《Liver Transplantation》2017,7(15)
A high voltage LiNi0.5Mn0.3Co0.2O2/graphite cell with a fluorinated electrolyte formulation 1.0 m LiPF6 fluoroethylene carbonate/bis(2,2,2‐trifluoroethyl) carbonate is reported and its electrochemical performance is evaluated at cell voltage of 4.6 V. Comparing with its nonfluorinated electrolyte counterpart, the reported fluorinated one shows much improved Coulombic efficiency and capacity retention when a higher cut‐off voltage (4.6 V) is applied. Scanning electron microscopy/energy dispersive X‐ray spectroscopy and X‐ray photoelectron spectroscopy data clearly demonstrate the superior oxidative stability of the new electrolyte. The structural stability of the bulk cathode materials cycled with different electrolytes is extensively studied by X‐ray absorption near edge structure and X‐ray diffraction. 相似文献
954.
Christine Nowak Jason K. Cheung Shara M. Dellatore Amit Katiyar Ram Bhat Joanne Sun 《MABS-AUSTIN》2017,9(8):1217-1230
Forced degradation studies have become integral to the development of recombinant monoclonal antibody therapeutics by serving a variety of objectives from early stage manufacturability evaluation to supporting comparability assessments both pre- and post- marketing approval. This review summarizes the regulatory guidance scattered throughout different documents to highlight the expectations from various agencies such as the Food and Drug Administration and European Medicines Agency. The various purposes for forced degradation studies, commonly used conditions and the major degradation pathways under each condition are also discussed. 相似文献
955.
Tien F. Lee Morton G. Burt Leonie K. Heilbronn Arduino A. Mangoni Vincent W. Wong Mark McLean N. Wah Cheung 《Cardiovascular diabetology》2017,16(1):157
Background
Hyperglycemia is associated with increased morbidity and mortality in patients with an acute myocardial infarction (AMI). We evaluated whether complications after AMI are associated with absolute or relative glycemia.Methods
A total of 192 patients with AMI were randomized to intensive or conventional insulin therapy. Absolute glycemia was defined as mean blood glucose level (BGL) during the first 24 h following randomization. Relative glycemia was defined by the stress hyperglycaemia ratio (SHR), calculated as mean BGL divided by average glucose concentration over the prior 3 months estimated from glycosylated haemoglobin. The primary endpoint was a “complicated AMI”, defined as an AMI complicated by death, congestive cardiac failure, arrhythmia, cardiac arrest, reinfarction, cardiogenic shock, inotrope use or emergency revascularization.Results
There was not a significant association between mean BGL and complicated AMI (odds ratio (OR) 1.05 per mmol/L glucose increment, 95% confidence intervals (CI) 0.93–1.19). In contrast, SHR was positively associated with a complicated myocardial infarction (OR 1.22 per 0.1 SHR increment, 95% CI 1.06–1.42), and individual complications of death (OR 1.55, 95% CI 1.14–2.11), congestive cardiac failure (OR 1.27, 95% CI 1.05–1.54), arrhythmia (OR 1.31, 95% CI 1.12–1.54) and cardiogenic shock (OR 1.42, 95% CI 1.03–1.97). The relationship between SHR and a complicated AMI was independent of diabetic status, intensive insulin therapy, sex and hypoglycemia.Conclusions
Relative, but not absolute, glycemia during insulin treatment is independently associated with complications after an AMI. Future studies should investigate whether basing therapeutic glycaemic targets on relative glycemia improves patient outcomes.956.
Phylogeography and pigment type diversity of Synechococcus cyanobacteria in surface waters of the northwestern pacific ocean 下载免费PDF全文
Xiaomin Xia Frédéric Partensky Laurence Garczarek Koji Suzuki Cui Guo Shun Yan Cheung Hongbin Liu 《Environmental microbiology》2017,19(1):142-158
The widespread unicellular cyanobacteria Synechococcus are major contributors to global marine primary production. Here, we report their abundance, phylogenetic diversity (as assessed using the RNA polymerase gamma subunit gene rpoC1) and pigment diversity (as indirectly assessed using the laterally transferred cpeBA genes, encoding phycoerythrin‐I) in surface waters of the northwestern Pacific Ocean, sampled over nine distinct cruises (2008–2015). Abundance of Synechococcus was low in the subarctic ocean and South China Sea, intermediate in the western subtropical Pacific Ocean, and the highest in the Japan and East China seas. Clades I and II were by far the most abundant Synechococcus lineages, the former dominating in temperate cold waters and the latter in (sub)tropical waters. Clades III and VI were also fairly abundant in warm waters, but with a narrower distribution than clade II. One type of chromatic acclimater (3dA) largely dominated the Synechococcus communities in the subarctic ocean, while another (3dB) and/or cells with a fixed high phycourobilin to phycoerythrobilin ratio (pigment type 3c) predominated at mid and low latitudes. Altogether, our results suggest that the variety of pigment content found in most Synechococcus clades considerably extends the niches that they can colonize and therefore the whole genus habitat. 相似文献
957.
Dianbo Qu Qing Li Hui-Ying Lim Nam Sang Cheung Rong Li Jerry H Wang Robert Z Qi 《The Journal of biological chemistry》2002,277(9):7324-7332
The neuronal Cdk5 kinase is composed of the catalytic subunit Cdk5 and the activator protein p35(nck5a) or its isoform, p39(nck5ai). To identify novel p35(nck5a)- and p39(nck5ai)-binding proteins, fragments of p35(nck5a) and p39(nck5ai) were utilized in affinity isolation of binding proteins from rat brain homogenates, and the isolated proteins were identified using mass spectrometry. With this approach, the nuclear protein SET was shown to interact with the N-terminal regions of p35(nck5a) and p39(nck5ai). Our detailed characterization showed that the SET protein formed a complex with Cdk5/p35(nck5a) through its binding to p35(nck5a). The p35(nck5a)-interacting region was mapped to a predicted alpha-helix in SET. When cotransfected into COS-7 cells, SET and p35(nck5a) displayed overlapping intracellular distribution in the nucleus. The nuclear co-localization was corroborated by immunostaining data of endogenous SET and Cdk5/p35(nck5a) from cultured cortical neurons. Finally, we demonstrated that the activity of Cdk5/p35(nck5a), but not that of Cdk5/p25(nck5a), was enhanced upon binding to the SET protein. The tail region of SET, which is rich in acidic residues, is required for the stimulatory effect on Cdk5/p35(nck5a). 相似文献
958.
The effects of different drying treatments (oven- andfreeze-drying) on protein extractability of three subtropical brownseaweeds, Sargassum hemiphyllum, S. henslowianum and S. patens, as well as in vitro protein digestibility and amino acid profileof their protein concentrates (PCs) were investigated. When comparedwith freeze-drying, oven-drying not only improved significantly (p <0.05, two-way ANOVA, Tukey-HSD) the protein extractability of thethree Sargassum species but also the protein quality (in vitroprotein digestibility) of their PCs. Therefore, oven-drying was found to bemore suitable for protein extraction of brown seaweeds. The relationshipsbetween the protein extractability and total phenolic content in seaweedsand between in vitro protein digestibility and total phenolic contentin PCs were also discussed. 相似文献
959.
Constitutive expression of LIGHT on T cells leads to lymphocyte activation, inflammation, and tissue destruction. 总被引:17,自引:0,他引:17
R B Shaikh S Santee S W Granger K Butrovich T Cheung M Kronenberg H Cheroutre C F Ware 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(11):6330-6337
LIGHT, a member of the TNF family of cytokines (homologous to lymphotoxin, exhibits inducible expression and competes with HSV glycoprotein D for herpesvirus entry mediator, a receptor expressed on T cells), is induced on activated T cells and mediates costimulatory and antitumor activity in vitro. Relatively little information is available on the in vivo effects of LIGHT expression, particularly within the T cell compartment. In this work, we describe transgenic mice that express human LIGHT under the control of the CD2 promoter, resulting in constitutive transgene expression in cells of the T lymphocyte lineage. LIGHT-transgenic animals exhibit abnormalities in both lymphoid tissue architecture and the distribution of lymphocyte subsets. They also show signs of inflammation that are most severe in the intestine, along with tissue destruction of the reproductive organs. These LIGHT-mediated effects were recapitulated when immune-deficient mice were reconstituted with bone marrow from LIGHT-transgenic donor mice. T cells in the LIGHT-transgenic mice have an activated phenotype and mucosal T cells exhibit enhanced Th1 cytokine activity. The results indicate that LIGHT may function as an important regulator of T cell activation, and implicate LIGHT signaling pathways in inflammation focused on mucosal tissues. 相似文献
960.
X Ouyang X Wang K Xu D Y Jin A L Cheung S W Tsao Y C Wong 《Biochimica et biophysica acta》2001,1541(3):212-220
Chromosomal instability (CIN) is one of the common features in prostate cancer, especially in advanced stages. Recently, the involvement of p53 in CIN through the regulation of centrosome amplification has been proposed in certain tumor types. In this study, we investigated the relationship between p53 and centrosome amplification in prostate cancer cells. Increased centrosome number and size were observed in DU145 and PC3 containing nonfunctional p53 compared to LNCap which expressed wild-type p53. Transfection of p53 into PC3 cells resulted in a decreased cell growth rate, G2/M arrest and decreased centrosome abnormalities. We provide the first evidence on a correlation between loss of p53 function and centrosome amplification in prostate cancer cells. Our results indicate that p53 may play a role in the regulation of centrosome amplification and loss of p53 may be one of the mechanisms involving CIN in prostate cancer cells. 相似文献