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71.
Avner Adini Irit Adini Etty Grad Yuval Tal Haim D. Danenberg Peter M. Kang Benjamin D. Matthews Robert J. DAmato 《International journal of molecular sciences》2021,22(10)
Myocardial infarction (MI) remains the leading cause of death in the western world. Despite advancements in interventional revascularization technologies, many patients are not candidates for them due to comorbidities or lack of local resources. Non-invasive approaches to accelerate revascularization within ischemic tissues through angiogenesis by providing Vascular Endothelial Growth Factor (VEGF) in protein or gene form has been effective in animal models but not in humans likely due to its short half-life and systemic toxicity. Here, we tested the hypothesis that PR1P, a small VEGF binding peptide that we developed, which stabilizes and upregulates endogenous VEGF, could be used to improve outcome from MI in rodents. To test this hypothesis, we induced MI in mice and rats via left coronary artery ligation and then treated animals with every other day intraperitoneal PR1P or scrambled peptide for 14 days. Hemodynamic monitoring and echocardiography in mice and echocardiography in rats at 14 days showed PR1P significantly improved multiple functional markers of heart function, including stroke volume and cardiac output. Furthermore, molecular biology and histological analyses of tissue samples showed that systemic PR1P targeted, stabilized and upregulated endogenous VEGF within ischemic myocardium. We conclude that PR1P is a potential non-invasive candidate therapeutic for MI. 相似文献
72.
Eric W. Neuman Benjamin J. Lai Jeremy L. Watts Gregory E. Hilmas William G. Fahrenholtz Laura Silvestroni 《International Journal of Applied Ceramic Technology》2021,18(6):2224-2236
Densification behavior, microstructure, and mechanical properties of zirconium diboride (ZrB2) ceramics modified with a complex Zr/Si/O-based additive were studied. ZrB2 ceramics with 5–20 vol.% additions of Zr/Si/O-based additive were densified to >95% relative density at temperatures as low as 1400°C by hot-pressing. Improved densification behavior of ZrB2 was observed with increasing additive content. The most effective additive amount for densification was 20 vol.%, hot-pressed at 1400°C (∼98% relative density). Microstructural analysis revealed up to 7 vol.% of residual second phases in the final ceramics. Improved densification behavior was attributed to ductility of the silicide phase, liquid phase formation at the hot-pressing temperatures, silicon wetting of ZrB2 particles, and reactions of surface oxides. Room temperature strength ranged from 390 to 750 MPa and elastic modulus ranged from 440 to 490 GPa. Vickers hardness ranged from 15 to 16 GPa, and indentation fracture toughness was between 4.0 and 4.3 MPa·m1/2. The most effective additive amount was 7.5 vol.%, which resulted in high relative density after hot-pressing at 1600°C and the best combination of mechanical properties. 相似文献
73.
Tang Guannan Gould Benjamin J. Ngowe Abigail Rollett Anthony D. 《Metallurgical and Materials Transactions A》2022,53(8):3204-3204
Metallurgical and Materials Transactions A - 相似文献
74.
Tang Guannan Gould Benjamin J. Ngowe Abigail Rollett Anthony D. 《Metallurgical and Materials Transactions A》2022,53(4):1486-1498
Metallurgical and Materials Transactions A - Hot cracking is one of the major defects that can occur in laser-based additive manufacturing. During the terminal stage of solidification, hot cracking... 相似文献
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We develop the theory for chromatographic separation of isomers such as polycyclic aromatic hydrocarbons, polychlorinated biphenyls, dioxins, steroids, and carotenoids based on shape-selective mechanisms for either exclusion or adsorption. Block-like solute transport and retention on oriented stationary phases are modeled by a dispersed-flow chromatographic equation combined with simultaneous exclusion partitioning and shaped-based adsorption. Molecules to be separated are considered distributed continuously with respect to the shape and sorption parameters. The population balance equations of distribution kinetics provide the governing differential equations that are solved for the temporal moments of the concentration in a chromatographic column. By including dispersive mass transport effects, the model allows estimation of peak variance and HETP and is thus an improvement over theories that focus solely on retention time. The model predictions are compared with experimental data from the literature for gas chromatography. 相似文献
79.
Benjamin D. Deacon A. Cecil Wamble 《Journal of the American Oil Chemists' Society》1954,31(7):284-287
Conclusions A procedure for the analysis of cottonseed and its products for Vitamin E has been developed and improved. The present procedure
generally gives good checks on duplicate analyses.
The Vitamin E content of whole cottonseed is somewhat more a function of variety than of locality. The 1952 crop of cottonseed
contained more Vitamin E than the 1951 crop. The two crops averaged 84 g. per ton and 68.5 g. per ton, respectively.
Most recent results show that there is no loss of Vitamin E in the storage of cottonseed or during the processing of the seed
for its oil and other products.
The hexane-soluble portion of a methanol extract of rolled or cooked cottonseed meats contains Vitamin E in concentrations
that have exceeded the values reported for wheat germ oil, the present commercial source.
A sample of commercial solvent extracted cottonseed meal was found to contain considerably less Vitamin E than hydraulic-
or screw-pressed meals.
The Vitamin E research described in this writing was conducted as a cooperative project of the Texas Engineering Experiment
Station and the Cotton Research Committee of Texas. 相似文献
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