This article assesses the historical foundations of how linearity at low dose became accepted by the scientiWc/regulatory communities. While the threshold model was used in the 1920s/1930s in establishing radiation health standards, its foundations were challenged by the genetics community who argued that radiation induced mutations in reproductive cells followed a linear response, were cumulat...

the standards of endodontics have constantly been raised in the last 25 years by practitioners’ researches and their interest. most of the scientists believe the recent developments and the use of lasers as the most exciting achievement in endodontic treatment. nowadays, lasers are being used in endodontics to improve the prognosis of the root-filled teeth. the implement of suitable wavelengths...

introduction: temporomandibular disorders (tmd) lead to masticatory muscle pain, jaw movement disability and limitation in mouth opening. pain is the chief complaint in 90% of the tmd patients which leads to disability and severe socioeconomic costs. the purpose of this study was to evaluate the therapeutic effects of low level laser therapy (lllt) compared to pharmacotherapy with nsaids (napro...

objectives: the purpose of this experimental study was to evaluate the efficacy of low level laser therapy (lllt) for pain reduction after midpalatal expansion in rats.   materials and methods: sixty male sprague six-week old rats weighing 180±10g were divided into seven groups (two experimental groups of 24 rats and one control group of 12 rats). the experimental groups were subjected to expan...

background: numerous in vitro reports suggest that low level laser therapy (lllt) affects cellular processes by biostimulation, however most of them emphasize on using visible light lasers which have low penetration. the aim of this study was to determine the effect of infrared laser light (which is more useful in clinic because of its higher penetration) on secretion of fibroblast growth facto...

one of the world's major mineral dust source regions lies along the border between iran and afghanistan. in this studyit is hypothesized that a low-level jet may play in role in generating the intensity of this source region. the presence of alow-level jet east of the seistan mountains is documented here for the first time. the jet exists mainly from may toseptember and has a core at 850 mb. ma...

We report on the mechanical behavior of an a-SiO2 84 kHz torsional oscillator operated between 100> or =T> or =1.0 mK. Below 10 mK we observed well-differentiated transient responses which we attribute to the interaction with low-level background radiation (gamma quanta and cosmic ray micro) and which can be modeled in terms of a change in the spring constant.