4 research outputs found
Flexibility of Various Nickel-Titanium Rotary Endodontic Files
Introduction: Nickel-titanium rotary files were originally developed to allow for greater flexibility when instrumenting root canals. The increased flexibility of nickel-titanium instruments allowed operators to negotiate canal curvatures with greater ease. File design is continually changing. Manufacturers are trying to produce files that will work more efficiently and safely. Knowing the properties of files marketed is especially important in helping to choose an appropriate file system. Current ISO standards require force measurements at a static point along the file. The purpose of this study was to evaluate the flexibility of four different nickel-titanium files at three different points along the file.
Materials and Methods: Flexibility of four different nickel-titanium rotary files (EndoSequence, ProFile, Vortex, and Vortex Blue) was measured. Each file was clamped at 3mm, 5mm, or 7mm (n = 10/length/file) and a universal testing machine was used to bend the files to a maximum deflection of 4.5mm. All data were statistically analyzed by two-way analysis of variance and post-hoc Tukey test (P = 0.05) to determine any significant differences.
Results: Statistically significant (P \u3c 0.05) differences were present. In general, ProFile was the stiffest, displaying the greatest force and bending moment values. Vortex Blue was significantly more flexible, with lower force needed for deflection and bending moments.
Conclusion: Vortex Blue files showed greater flexibility compared with the other nickel-titanium rotary files studied
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The Equinox2020 Seshat data release
This report describes the current canonical time-series dataset named “Equinox2020,” a subset of Seshat: Global History Databank data for a well-curated list of polities and variables available on the Seshat Data Browser. The report provides an introduction to the methods and procedures of the Seshat project relating to the curation and release of the Equinox2020 dataset
A cross-disorder dosage sensitivity map of the human genome
Rare copy-number variants (rCNVs) include deletions and duplications that occur infrequently in the global human population and can confer substantial risk for disease. In this study, we aimed to quantify the prop-erties of haploinsufficiency (i.e., deletion intolerance) and triplosensitivity (i.e., duplication intolerance) throughout the human genome. We harmonized and meta-analyzed rCNVs from nearly one million individuals to construct a genome-wide catalog of dosage sensitivity across 54 disorders, which defined 163 dosage sensitive segments associated with at least one disorder. These segments were typically gene dense and often harbored dominant dosage sensitive driver genes, which we were able to prioritize using statistical fine-mapping. Finally, we designed an ensemble machine-learning model to predict probabilities of dosage sensitivity (pHaplo & pTriplo) for all autosomal genes, which identified 2,987 haploinsufficient and 1,559 trip-losensitive genes, including 648 that were uniquely triplosensitive. This dosage sensitivity resource will pro-vide broad utility for human disease research and clinical genetics