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121.
Bandgap Tunability in Sb‐Alloyed BiVO4 Quaternary Oxides as Visible Light Absorbers for Solar Fuel Applications
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122.
Engaging High‐Sensation Seekers: The Dynamic Interplay of Sensation Seeking,Message Visual‐Auditory Complexity and Arousing Content
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Zheng Wang Mao Vang Kathryn Lookadoo John M. Tchernev Cody Cooper 《The Journal of communication》2015,65(1):101-124
This study extends the research on message‐sensation value (MSV) by treating it as a dynamic stream of complex visual‐auditory information and arousing content (MSV‐d). Real‐time attentional and emotional responses to this dynamic stream during the PSA viewing process are indicated by psychophysiological measures. Dynamic models are used to systematically examine endogenous and exogenous influences on message processing to more accurately understand the effects of MSV‐d variables and individuals' sensation seeking tendencies during the processing of the PSAs. An important finding is that generally, increasing visual‐auditory complexity activates an approach tendency in those with high sensation‐seeking tendencies but activates an avoidance tendency in those with low sensation‐seeking tendencies, and this response pattern is moderated by arousing content. 相似文献
123.
Ming Zhou Hidetaka Hara Yifan Dai Lisha Mou David K. C. Cooper Changyou Wu Zhiming Cai 《International journal of molecular sciences》2016,17(8)
Different cell types possess different miRNA expression profiles, and cell/tissue/organ-specific miRNAs (or profiles) indicate different diseases. Circulating miRNA is either actively secreted by living cells or passively released during cell death. Circulating cell/tissue/organ-specific miRNA may serve as a non-invasive biomarker for allo- or xeno-transplantation to monitor organ survival and immune rejection. In this review, we summarize the proof of concept that circulating organ-specific miRNAs serve as non-invasive biomarkers for a wide spectrum of clinical organ-specific manifestations such as liver-related disease, heart-related disease, kidney-related disease, and lung-related disease. Furthermore, we summarize how circulating organ-specific miRNAs may have advantages over conventional methods for monitoring immune rejection in organ transplantation. Finally, we discuss the implications and challenges of applying miRNA to monitor organ survival and immune rejection in allo- or xeno-transplantation. 相似文献
124.
Ramona Erber Steffen Spoerl Andreas Mamilos Rosemarie Krupar Arndt Hartmann Matthias Ruebner Juergen Taxis Mareike Wittenberg Torsten E. Reichert Gerrit Spanier Silvia Spoerl 《International journal of molecular sciences》2022,23(1)
Oral cancer often presents with aggressive behavior and a high risk of recurrence and metastasis. For oral squamous cell carcinoma (OSCC), which is the most frequent histological subtype, therapy strategies include surgery, radiation therapy, chemotherapy, immune checkpoint inhibitors, and EGFR inhibitors. Recently, a Trop-2 antibody-drug conjugate (ADC) has been approved in the United States of America for the treatment of advanced triple-negative breast cancer. However, this ADC has also been tested in other solid tumors including head & neck squamous cell carcinoma. The prognostic impact of Trop-2 has already been reported for several cancers. We studied the prognostic influence of Trop-2 protein expression on OSCC patients’ survival. The cohort comprised n = 229 OSCC patients with available archived tumor tissue and corresponding non-neoplastic oral mucosa tissue. Using immunohistochemistry, we investigated Trop-2 expression in both the central and peripheral regions of each tumor and in corresponding non-neoplastic oral mucosa. In patients suffering from OSCC with combined high central and low peripheral Trop-2 expression, five-year overall survival (OS) was 41.2%, whereas 55.6% of OSCC patients who presented lower central and/or higher peripheral tumoral Trop-2 expression were alive after five years (p = 0.075). In multivariate Cox regression, the expression pattern of high central tumoral and lower peripheral Trop-2 expression was significantly correlated with impaired OS (HR = 1.802, 95%-CI: 1.134–2.864; p = 0.013) and recurrence-free survival (RFS) (HR = 1.633, 95%-CI: 1.042–2.560; p = 0.033), respectively, when adjusting for co-variables. Hence, Trop-2 may serve as an independent prognostic biomarker in OSCC. In subsequent studies, the pathophysiological meaning of downregulated Trop-2 expression in the OSCC periphery has to be analyzed. 相似文献
125.
W. A. Van Sickle M. R. Angelastro P. Wilson J. R. Cooper A. Marquart M. A. Flanagan 《Lipids》1992,27(3):157-160
Two squalene derivatives, trisnorsqualene cyclopropylamine and trisnorsqualeneN-methylcyclopropylamine, were synthesized and tested for inhibition of lanosterol and squalene epoxide formation from squalene
in rat hepatic microsomes, and for the inhibition of cholesterol syntheses in human cultured hepatoblastoma (HepG2) cells.
Trisnorsqualene cyclopropylamine inhibited [3H]-squalene conversion to [3H]squalene epoxide in microsomes (IC50=5.0 μM), indicating that this derivative inhibited squalene mono-oxygenase. Trisnorsqualenen-methylcyclopropylamine inhibited [3H]squalene conversion to [3H]lanosterol (IC50=12.0 μM) and caused [3H]-squalene epoxide to accumulate in microsomes, indicating that this derivative inhibited 2,3-oxidosqualene cyclase. Cholesterol
biosynthesis from [14C]acetate in HepG2 cells was inhibited by both derivatives (IC50=1.0 μM for trisnorsqualene cyclopropylamine; IC50=0.5 μM for trisnorsqualeneN-methylcyclopropylamine). Cells incubated with trisnorsqualene cyclopropylamine accumulated [14C]squalene, while cells incubated with trisnorsqualeneN-methylcyclopropylamine accumulated [14C]squalene epoxide and [14C]squalene diepoxide. The concentration range of inhibitor which caused these intermediates to accumulate coincided with that
which inhibited cholesterol synthesis. The results indicate that cyclopropylamine derivatives of squalene are effective inhibitors
of cholesterol synthesis, and that substitutions at the nitrogen affect enzyme selectivity and thus the mechanism of action
of the compounds. 相似文献
126.
Experiments are reported in which individual bubbles of vapour are grown at a plane wall in initially stagnant isothermal liquid. Such tests had already been done and satisfactorily analysed and understood for pure liquids, but here the liquids are binary mixtures of hexane and octane of varying composition.The chief result is that ciné observations of the general behaviour of such bubbles (rate of growth, change of shape, time and size at departure) presents no new problems; it is identical to behaviour in pure liquids, provided one change of parameter is made. That change is to substitute the correct temperature for the evaporating binary interface in place of the saturation temperature for the pure liquid. That interface temperature was determined by reference to recent analytic solutions for evaporation of semi-infinite binary liquid by diffusion of heat and mass.Detailed rapid thermometric observations were also made, of the temperatures at the wall below the bubble and inside the bubble. They showed some aspects which differ markedly from pure liquids (though not such as to affect general behaviour). Those aspects were explained by detailed analysis of diffusion of heat and mass in a thin layer of liquid (microlayer) left beneath the growing bubble.Implications for boiling heat transfer are also considered and it is shown that this analysis of individual bubbles does not, of itself, explain the known reduction in heat transfer coefficient between pure and binary liquids. Several existing methods of explaining that reduction are examined and shown to have a common basis close to that determined by our analysis of single bubbles. But on extending from that basis in a simple way, to predict boiling heat transfer rates, they fail, except where an additional pressure-dependent multiplier is introduced, on purely empirical grounds. 相似文献
127.
为了保护自然环境和地下水,处于对人类生存和发展的需要,原有的具有破坏臭氧层物质(ODS)的清洗剂将会退出市场,行业召唤创新的清洗剂技术。本文从霍尼韦尔公司的内部采购案例开始,分析了行业的需求与挑战,通过对比霍尼韦尔氟化学品部的Solstice高性能溶剂(SolsticePF)与现有几种主要清洗剂的性能优劣,显示了Solstice高性能溶剂在环保、安全和清洁等方面的优异性能,从而说明创新的环保型绿色无污染的工业清洗剂将成为未来中国清洗剂工业市场发展的主流。 相似文献
128.
129.
This paper describes MetaIndex, an automatic indexing program that creates symbolic representations of documents for the purpose of document retrieval. MetaIndex uses a simple transition network parser to recognize a language that is derived from the set of main concepts in the Unified Medical Language System Metathesaurus (Meta-1). MetaIndex uses a hierarchy of medical concepts, also derived from Meta-1, to represent the content of documents. The goal of this approach is to improve document retrieval performance by better representation of documents. An evaluation method is described, and the performance of MetaIndex on the task of indexing the Slice of Life medical image collection is reported. 相似文献
130.
We examine further the electrochemical oxidation of carbon in molten carbonate, based on analysis of published research. Ascending and descending branches of voltage hysteresis found in current sweeps of atomically-ordered graphite and of disordered carbon (coal char) are separated by about 0.20–0.25 V and by 0.10–0.15 V for ordered and disordered forms, respectively, over a wide band of current density, 0.03–0.10 A/cm2. The higher voltage of the descending branch is in rough agreement with prediction of the Y. Li model for the carbon/carbonate electrode in the same current range, for ordered graphite (La = 70–100 nm) and for disordered structures (La = 3–5 nm), respectively. We suggest that the amplitude of the hysteresis represents the difference between the overvoltage requirements for 2- and 4 electron net transfer processes, respectively. The 2 e− reaction (C + CO32− = CO + CO2 + 2e−) dominates the low current segment (LCS) of our previous analysis, and the more hindered 4e− transfer reaction (C + 2CO32− = 3CO2 + 4e−) dominates the high current segment (HCS). The voltage increase separating LCS from HCS is effected by accumulation of CO2 within small, melt-filled pores to form highly supersaturated solutions of CO2, which enhance anode voltage by a concentration overpotential of 0.10–0.25 V. Overpotential increases with reaction extent until (1) overall polarization inhibits the interior reaction and shifts CO2 production to the more accessible exterior surface, or, (2) at a critical concentration (dependent on surface tension and pore diameter) bubbles nucleate and block current flow in the pores. Further support for this picture comes from the often-reported deviation of the gas composition from the CO/CO2 ratio of the Boudouard equilibrium at atmospheric pressure, as open circuit conditions are approached in an electrochemical cell. Our interpretation accounts for the mole fraction of CO2 at open circuit being greater than predicted from the Boudouard equilibrium. 相似文献