Forensic Microscope
Welcome to Forensic MicroscopeEffect of Sodium Carbonate Solution on Self-setting Properties of Tricalcium Silicate Bone Cement
Effect of Sodium Carbonate Solution on Self-setting Properties of Tricalcium Silicate Bone Cement
In this study, the effects of sodium carbonate (Na2CO3 ) solution with different concentrations (10, 15, 20, and 25 wt%) as liquid phase on the setting time and compressive strength of tricalcium silicate bone cements are investigated. The in vitro bioactivity and degradability of the resultant Ca3SiO5-Na2CO3 solution paste was also studied. The results indicate that as the concentration of Na2CO3 solution varies from 0 to 25 wt%, the initial and final setting time of the cement decrease significantly from 90 to 20 min and from 180 to 45min, respectively. After setting for 24 h, the compressive strength of Ca3SiO5-Na2CO3 solution paste reaches 5.1MPa, which is significantly higher than that of Ca 3SiO5-water cement system. The in vitro bioactivity of the cements is investigated by soaking in simulated body fluid (SBF) for 7 days. The results show that the Ca3SiO5-Na2CO 3 solution bone cement has a good bioactivity and can degrade in Ringer's solution. The results indicate that Na2CO3 solution as a liquid phase significantly improves the self-setting properties of Ca 3SiO5 cement as compared to water. The Ca3SiO 5 cement paste prepared using Na2CO3 solution shows good bioactivity and moderate degradability, and the Ca3SiO 5-Na2CO3 solution system may be used as degradable and bioactive bone defect filling materials.
Click Here to read the entire article...
Other Articles:
| • | University of Colorado Awarded Patent Licensed to ALD NanoSolutions, Inc. |
| The University of Colorado has been awarded U.S. Patent number 7,426,067 'Atomic layer deposition on micro-mechanical devices,' which has been exclusively licensed to ALD NanoSolutions, Inc. | |
| Click Here to read the entire article... |
|
| • | Pomology: Fruit Cultivation and Production |
| Provides links to websites and research articles in the applied life science pomology. The site focusses on the numerous scientific and commercial aspects of the cultivation and production of temperate, subtropical and tropical fruits. | |
| Click Here to read the entire article... |
|
| • | Pavement Sealcoat Linked To Urban Lake Contamination In The Central And Eastern United States |
| Dust collected from coal-tar sealcoated parking lots in Central and Eastern U.S. cities contains concentrations of polycyclic aromatic hydrocarbons (PAHs) that are about 1,000 times greater than levels found in Western cities where coal-tar sealcoat is less commonly used, according to a new study. |
|
| Click Here to read the entire article... |
|
| • | Effect of stand density on oak regeneration in flood plain forests in Lower Silesia, Poland |
|
The paper describes the structure, growth and vitality of natural oak regeneration in relation to stand density. To gain a better understanding of regeneration strategies, the investigation was carried out in oak forest flood plains in Poland, which were flooded in the summer of 1997. To study the stand structure and regeneration, 108 circular plots were established in stands managed using the shelterwood system. In addition, five gaps were chosen in a stand managed using the group cutting system (Legnica forest district). The results of the study showed that oak regenerated spontaneously in all stands. The abundance and vitality of oak seedlings and saplings were very high. The number of oak seedlings and saplings significantly depended on stand density. The greatest maximum height was found in gaps (146.0 cm) and in a stand with open canopy (88.9 cm) in Wolów. In Wolów and Miekinia, the shortest oaks grew in the worst light conditions. To regenerate naturally, oak stands in preparatory cutting should be reduced in the number of trees per hectare to ~150 and decreased in basal area to ~26 m2 ha–1. The group cutting system can be used in oak stands growing on flood plain sites, but there is the danger of ground vegetation development in openings. |
|
| Click Here to read the entire article... |
|
| • | Introduction to bleeding |
| Identifying if it is a minor or severe wound | |
| Click Here to read the entire article... |
|
| • | Development and optimization of an internally controlled dried blood spot assay for surveillance of human immunodeficiency virus type-1 drug resistance |
|
We present the evaluation of a methodology for the genotypic assessment of human immunodeficiency virus type-1 (HIV-1) drug resistance, optimized for use with dried blood spots (DBS). The ability to generate HIV-1 protease (PR) and reverse transcriptase (RT) contiguous amplicons and nucleotide sequences from DBS was evaluated. Different collection matrices and extraction methodologies were compared. The relative subtype sensitivity of the amplification strategy was assessed using a comprehensive panel of plasmids representing A–H subtypes. A panel of DBS and plasma specimens was subjected to HIV genotyping. Sequences generated from each sample type were compared. Extensive replicate testing revealed most sensitivity with the use of 903 filter paper and silica/guanidine extraction, which had an estimated 95% inclusivity endpoint of 1542 proviral copies/mL, as compared with 21 573 proviral copies/mL for the FTA system. All HIV-1 group M subtypes analysed—with the exception of subtypes A2, AE, AG, F and H—had a relative sensitivity of ≤10 plasmid copies/PCR reaction. The PCR was multiplexed to include amplification of a human housekeeping gene to monitor the integrity of the human genomic DNA. Using a panel of clinical samples, we demonstrated the ability to amplify and sequence from 83% (n = 10) in the PR region and 100% (n = 12) in the RT region, of samples with detectable viral load. All specimens with an HIV-1 RNA load ≥1000 copies/mL were successfully amplified and sequenced. Twelve specimens had pol genotyping from both plasma and DBS samples. Sequence analysis and drug resistance interpretation revealed that 10 (83%) provided concordant drug resistance interpretation. Our results demonstrate that the technique is appropriate for surveillance of drug resistance in untreated individuals and those with virological failure on therapy. |
|
| Click Here to read the entire article... |
|
By michael@nanowerk.com (Michael Berger) - Copyright 2005-2008 Nanowerk LLC - version: v1.5 build A