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Influence of Irrigation with NaOCl and Chlorhexidine on Microleakage

References 1. Athanassiadis B, Abbott PV, Walsh LJ . The use of calcium hydroxide, antibiotics and biocides as antimicrobial medicaments in endodontics. Aust Dent J , 2007; 52(1):64-82. 2. Krishnamurthy S, Shashikala S . Evaluation and Prevention of the Precipitate Formed on Interaction between Sodium Hypochlorite and Chlorhexidine. J Endod , 2010; 36:1154-1157 3. Bui TB, Baumgartner JC, Mitchell JC . Evaluation of the interaction between Sodium Hypochlorite and Chlorhexidine Gluconate and its Effect on Root Dentin. 4. Spångberg L

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Development of spray-dried co-precipitate of amorphous celecoxib containing storage and compression stabilizers

Development of spray-dried co-precipitate of amorphous celecoxib containing storage and compression stabilizers

The purpose of this study was to obtain an amorphous system with minimum unit operations that will prevent recrystallization of amorphous drugs since preparation, during processing (compression) and further storage. Amorphous celecoxib, solid dispersion (SD) of celecoxib with polyvinyl pyrrollidone (PVP) and co-precipitate with PVP and carrageenan (CAR) in different ratios were prepared by the spray drying technique and compressed into tablets. Saturation solubility and dissolution studies were performed to differentiate performance after processing. Differential scanning calorimetry and X-ray powder difraction revealed the amorphous form of celecoxib, whereas infrared spectroscopy revealed hydrogen bonding between celecoxib and PVP. The dissolution profile of the solid dispersion and co-precipitate improved compared to celecoxib and amorphous celecoxib. Amorphous celecoxib was not stable on storage whereas the solid dispersion and co-precipitate powders were stable for 3 months. Tablets of the solid dispersion of celecoxib with PVP and physical mixture with PVP and carrageenan showed better resistance to recrystallization than amorphous celecoxib during compression but recrystallized on storage. However, tablets of co-precipitate with PVP and carageenan showed no evidence of crystallinity during stability studies with comparable dissolution profiles. This extraordinary stability of spray-dried co-precipitate tablets may be attributed to the cushioning action provided by the viscoelastic polymer CAR and hydrogen bonding interaction between celecoxib and PVP. The present study demonstrates the synergistic effect of combining two types of stabilizers, PVP and CAR, on the stability of amorphous drug during compression and storage as compared to their effect when used alone.

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Comparison of temperature dependence of internal damping of selected magnesium alloys

.F., Wang, J.B., Gui, J.N., Zheng, O., 2007. In situ observation of ageing process and new morphologies of continuous precipitates in AZ91 magnesium alloy , Materials Letters, 61, 4707-4710.

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Pigments precipitated from chromate post-galvanic solutions in emulsion systems

References Krysztafkiewicz A.: Modified calcium silicates as active rubber fillers, J. Mater. Sci. , 1987 , 22, 478. Krysztafkiewicz A., Modified zinc silicate - an active rubber activator and filler, J. Mater. Sci. , 1988 , 23, 2407. Krysztafkiewicz A., Werner R., Lipska K. L., Jesionowski T.: Effect of silane coupling agents on properties of precipitated sodium-aluminium silicates, Colloids Surf. A , 2001 , 182, 73. Klapiszewska B., Krysztafkiewicz

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Possibility of GPS precipitable water vapour for reservoir inflow forecasting

. Hydrological Processes. Vol. 30. Iss. 23 p. 4420–4433. B evis M., B usinger S., C hiswell S., H erring T.A., A nthes R.A., R ocken C., W are R.H. 1994. GPS Meteorology: Mapping zenith wet delays onto precipitable water. Journal of Applied Meteorology. Vol. 33 p. 379–386. B ordi I., R aziei T., P ereira L.S., S utera A. 2014. Ground-Based GPS measurements of precipitable water vapor and their usefulness for hydrological applications. Water Resources Management. Vol. 29. Iss. 2 p. 471–486. B ordi I., Z hu X., F raedrich K. 2016. Precipitable

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Analysis of precision and accuracy of Precipitable Water Vapour derived from GPS observations

Precipitable Water Vapour Monitoring Using GNSS. Contr. Geophys. Geod. , 38, 1, 17-24. Saastamoinen J., 1972: Atmospheric correction for the troposphere and stratosphere in radio ranging of satellites. In: The Use of Artificial Satellites for Geodesy in Geodesy. Volume Geophys. Monogr. Ses. 15, 247-251. AGU, Washington, D. C. Taylor R. J., 1999: An Introduction to Error Analysis: The Study of Uncertainties in Physical Measurements. University Science Books, 304 p. (http://books.google.com/books?id=giFQcZub80oC) http

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Precipitable Water Vapour and Zenith Total Delay time series and models over Slovakia and vicinity

-41. Hefty J., Igondová M., Droščák B., 2009: Homogenization of Long-Term GPS Monitoring Series at Permanent Stations in Central Europe and Balkan Peninsula. Contrib. Geophys. Geod., 39 , 1, 19-42. Igondová M., Hefty J., 2008: Continuous Precipitable Water Vapour Monitoring Using GNSS. Contrib. Geophys. Geod., 38 , 2, 151-167. Saastamoinen J., 1972: Atmospheric Correction for the Troposphere and Stratosphere in Radio Ranging of Satellites. In: The Use of Artificial Satellites for Geodesy in Geodesy. Volume Geophys

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Integrated Precipitable Water from GPS Observations and CIMEL Sunphotometer Measurements at CGO Belsk

., Herring, T. A., Anthes, R.A., Rocken, C., & R. Ware (1994). GPS Meteorology: Mapping Zenith Wet Delays onto Precipitable Water, Journal of Applied Meteorology, Vol. 33, pp. 379-386 Böhm, J. & Schuh, H., (2013). Atmospheric Effects in Space Geodesy, Springer Heidelberg New York Dordrecht London, DOI:10.1007/978-3-642-36932-2 Davis, J. L., Herring, T. A., Shapiro, I. I., Rogers, A. E. & G. Elgered (1985). Geodesy by radio interferometry: Effects of atmospheric modeling errors on estimates of baseline length, Radio Science, 20, pp. 1593

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Determination of Zenith Tropospheric Delay and Precipitable Water Vapor using GPS Technology

. Boers, D. O’Brien, and M. Hendy, “Accuracy of absolute precipitable water vapor estimates from GPS observations,” J. Geophys. Res. , vol. 103, no. D22, p. 28701, Nov. 1998. [5] T. Nilsson, J. Böhm, D. Wijaya, A. Tresch, V. Nafisi, and H. Schuh, “Path Delays in the Neutral Atmosphere,” in Atmospheric Effects in Space Geodesy SE - 3 , J. Böhm and H. Schuh, Eds. Springer Berlin Heidelberg, 2013, pp. 73–136. [6] S. Katsougiannopoulos, C. Pikridas, D. Rossikopoulos, I. Ifadis, and A. Fotiou, “Tropospheric refraction estimation using various models, radiosonde

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Integrated Precipitable Water Vapour Measurements At Polish Polar Station Hornsund From GPS Observations Verified By Aerological Techniques

., Businger, S., Rocken, C., Solheim, F., Van Hove, T., Ware, R., McClusky, S., Herring, T. A. & King, R. W. (1996). GPS meteorology: direct estimation of the absolute value of precipitable water. J. Applied Met. 35, 830–838. doi:10.1175/1520-0450 Halthore, R.N., Eck, T.F., Holben B.N., & Markham, B.L. (1997). Sunphotometric Measurements of Atmospheric Water Vapor Column Abundance in the 940-nm Band. J. Geophys. Res. , 102, pp 4343-4352 Holben, B.N., Tanre, D., Smirnov, A., Eck, T.F., Slutsker, I., N. Abuhassan, W.W. Newcomb, J. Schafer, B. Chatenet, F

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