0000000000040220

AUTHOR

Sean Li

Ahlfors-regular distances on the Heisenberg group without biLipschitz pieces

We show that the Heisenberg group is not minimal in looking down. This answers Problem 11.15 in `Fractured fractals and broken dreams' by David and Semmes, or equivalently, Question 22 and hence also Question 24 in `Thirty-three yes or no questions about mappings, measures, and metrics' by Heinonen and Semmes. The non-minimality of the Heisenberg group is shown by giving an example of an Ahlfors $4$-regular metric space $X$ having big pieces of itself such that no Lipschitz map from a subset of $X$ to the Heisenberg group has image with positive measure, and by providing a Lipschitz map from the Heisenberg group to the space $X$ having as image the whole $X$. As part of proving the above re…

research product

Radiofrequency Ablation for Chronic Lumbar Zygapophyseal Joint Pain Using a V-Shaped Active Tip Needle: An Observational Retrospective Study

Giuliano Lo Bianco,1,2 Giovanni Misseri,2 Agnes R Stogicza,3 Gregoretti Cesare,2,4 Sean Li,5 Miles Day,6 David J Kennedy,7 Michael E Schatman8,9 1Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy; 2Anesthesiology and Pain Department, Fondazione Istituto “G. Giglio”, Cefalù, Palermo, Italy; 3Anesthesia and Pain, Saint Magdolna Private Hospital, Budapest, Hungary; 4Department of Surgical, Oncological and Oral Science (Di.Chir.On.S.), University of Palermo, Palermo, Italy; 5National Spine and Pain Centers, Shrewsbury, NJ, USA; 6Pain Research, The Pain Center at Grace Clinic, Texas Tech University HSC, Lubbock, TX, USA; 7Department of PM&R, V…

research product