Background: In a previous investigation we reported on magnetic forces in the static magnetic field of a 1.5 Tesla MRI system. The aim of the present investigation was to assess forces on orthodontic wires in a high field strength MRI system at 3 Tesla.
Materials And Methods: Thirty-two different orthodontic wires (21 archwires, eight ligature wires and three retainer wires) were investigated in a 3 Tesla high field strength MRI system (Intera, Philips Medical Systems, Best, The Netherlands). Translational forces were measured by the deflection angle test (ASTM F2052-02), and rotational forces assessed on a 5-point qualitative scale.
Results And Conclusion: Translational forces ranged between 43.5 mN and 136.1 mN for retainer wires and between 0.6 mN (Noninium) and 208.4 mN (Orthos Stainless Steel) for steel archwires. Translational forces were up to 53.8 times as high as gravitational forces for retainer wires and up to 54.5 times as high for steel archwires, associated with marked rotational forces for the most part. Archwires manufactured from nickel-titanium, titanium-molybdenum and cobalt-chromium and different ligature wires showed no or negligible forces in the magnetic field. Carefully ligated wires should not present a risk due to translational and rotational forces in the high field MRI system at 3 Tesla.
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BioDrugs
January 2025
Orsay-Vallée Campus, Paris-Saclay University, Gif-sur-Yvette, France.
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High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, China.
PhoCl is a photocleavable protein engineered from a green-to-red photoconvertible fluorescent protein by circular permutation, and has been used in various optogenetic applications including precise control of protein localization and activity in cells. Upon violet light illumination, PhoCl undergoes a β-elimination reaction to be cleaved at the chromophore, resulting in spontaneous dissociation into a large empty barrel and a small C-terminal peptide. However, the structural determinants and the mechanism of the PhoCl photocleavage remain elusive, hindering the further development of more robust photocleavable optogenetic tools.
View Article and Find Full Text PDFJ Mol Model
January 2025
Shanxi Jiangyang Chemical Limited Company, Taiyuan, 030041, Shanxi, China.
Context: DNAN/DNB cocrystals, as a newly developed type of energetic material, possess superior safety and thermal stability, making them a suitable alternative to traditional melt-cast explosives. Nonetheless, an exploration of the thermal degradation dynamics of the said cocrystal composite has heretofore remained uncharted. Consequently, we engaged the ReaxFF/lg force field modality to delve into the thermal dissociation processes of the DNAN/DNB cocrystal assembly across a spectrum of temperatures, encompassing 2500, 2750, 3000, 3250, and 3500 K.
View Article and Find Full Text PDFIntegr Psychol Behav Sci
January 2025
Faculty of Management, University of Tehran Tehran Province, Tehran Jalal-e-Al-e-Ahmad Hwy & Chamran Hwy, Tehran, Iran.
Time dilation is an important issue in the field of physics. Introduced by the special relativity theory, it means that the time duration spent by an entity to reach a certain destination depends on the movement and speed of the entity. Time dilation has been widely addressed in other disciplines, including philosophy, psychology, and motivation.
View Article and Find Full Text PDFExposure to toxins causes lasting damaging effects on the body. Numerous studies in humans and animals suggest that diet has the potential to modify the epigenome and these modifications can be inherited transgenerationally, but few studies investigate how diet can protect against negative effects of toxins. Potential evidence in the primary literature supports that caloric restriction, high-fat diets, high protein-to-carbohydrate ratios, and dietary supplementation protect against environmental toxins and strengthen these effects on their offspring's epigenome.
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