The variation in the magnetic susceptibility over a temperature range for some complexes of osmium, ruthenium, rhenium and iridium, in d,3, d$ and dl configuration, have been measured. This variation in susceptibility has been discussed in terms of the Kotani theory and the relative importance of the various assumptions made in this theory are examined in the light of the magnetic data.

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Detection of colorectal polyps through colonoscopy is an essential practice in prevention of colorectal cancers. However, the method itself is labor intensive and is subject to human error. With the advent of deep learning-based methodologies, and specifically convolutional neural networks, an opportunity to improve upon the prognosis of potential patients suffering with colorectal cancer has appeared with automated detection and segmentation of polyps. Polyp segmentation is subject to a number of problems such as model overfitting and generalization, poor definition of boundary pixels, as well as the model’s ability to capture the practical range in textures, sizes, and colors. In an effort to address these challenges, we propose a dual encoder–decoder solution named Polyp Segmentation Network (PSNet). Both the dual encoder and decoder were developed by the comprehensive combination of a variety of deep learning modules, including the PS encoder, transformer encoder, PS decoder, enhanced dilated transformer decoder, partial decoder, and merge module. PSNet outperforms state-of-the-art results through an extensive comparative study against 5 existing polyp datasets with respect to both mDice and mIoU at 0.863 and 0.797, respectively. With our new modified polyp dataset we obtain an mDice and mIoU of 0.941 and 0.897 respectively.

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The deuterium quadrupole doublet splittings and spin–lattice relaxation times (T1) are measured as a function of temperature in the nematic phase of p-methoxy-d3-benzylidene-d1-p-n-butyl-d9-aniline (MBBA-d13). It is shown that a single order parameter tensor is sufficient to fully describe the orientational order of the molecule even though the molecule is nonrigid. The molecular conformational averages, which are different for various C–D bonds, result in resolved deuterium NMR spectra from which the T1 for each deuteron site can be measured. While the simplest approach in treating order director fluctuations, in which molecular reorientations and collective fluctuation modes are assumed to be uncoupled, fails to explain our T1 data for all deuterons, Freed’s treatment of spin relaxation in liquid crystals does give a qualitative explanation. Using this theory, molecular reorientation times for different deuteron sites are estimated.