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Considered are 80 sets of layer groups, each set consisting of four groups: ordinary single and double, and grey single and double layer groups. The structural properties of layer groups (factorization into cyclic subgroups and the existence of grading according to the sequence of halving subgroups) enable efficient symbolic computation (by the POLSym code) of the relevant properties, real and complex irreducible and allowed (half-)integer (co-)representations in particular. This task includes, as the first step, classification of the irreducible domains based on the group action in the Brillouin zone combined with torus topology. Also, the band (co-)representations induced from the irreducible (co-)representations of Wyckoff-position stabilizers (site-symmetry groups) are decomposed into the irreducible components. These, and other layer group symmetry related theoretical data relevant for physics, layered materials in particular, are tabulated and made available through the web site https://nanolab.group/layer/.

Metabolic syndrome (MetS) is a combination of cardiovascular risk factors associated with type 2 diabetes, obesity, and cardiovascular diseases. The circadian clock gene polymorphisms are very likely to participate in metabolic syndrome genesis and development. However, research findings of the association between circadian rhythm gene polymorphisms and MetS and its comorbidities are not consistent. In this study, a review of the association of circadian clock gene polymorphisms with overall MetS risk was performed. In addition, a meta-analysis was performed to clarify the association between circadian clock gene polymorphisms and MetS susceptibility based on available data. The PubMed and Scopus databases were searched for studies reporting the association between circadian rhythm gene polymorphisms (ARNTL, BMAL1, CLOCK, CRY, PER, NPAS2, REV-ERBα, REV-ERBβ, and RORα) and MetS, and its comorbidities diabetes, obesity, and hypertension. Thirteen independent studies were analyzed with 17,381 subjects in total. The results revealed that the BMAL1 rs7950226 polymorphism was associated with an increased risk of MetS in the overall population. In contrast, the CLOCK rs1801260 and rs6850524 polymorphisms were not associated with MetS. This study suggests that some circadian rhythm gene polymorphisms might be associated with MetS in different populations and potentially used as predictive biomarkers for MetS.

Symmetry indicates that low energy spectra of materials could be richer than well-known Dirac, semi-Dirac, or quadratic, hosting some unusual quasiparticles. Performing the systematic study of exact forms of low energy effective Hamiltonians and dispersions in high-symmetry points with fourfold degeneracy of bands, we found new, previously unreported dispersion, which we named poppy flower (PF) after its shape. This massless fermion exists in non-magnetic two-dimensional (2D) crystals with spin-orbit coupling (SOC), which are invariant under one of the proposed ten noncentrosymmetric layer groups. We suggest real three-dimensional (3D) layered materials suitable for exfoliation, having layers that belong to these symmetry groups as candidates for realization of PF fermions. In 2D systems without spin-orbit interaction, fortune teller (FT)-like fermions were theoretically predicted, and afterward experimentally verified in the electronic structure of surface layer of silicon. Herein, we show that such fermions can also be hosted in 2D crystals with SOC, invariant under additional two noncentrosymmetric layer groups. This prediction is confirmed by density functional based calculation: layered BiIO 4 , which has been synthesized already as a 3D crystal, exfoliates to stable monolayer with symmetry pb 2 1 a , and FT fermion is observed in the band structure. Analytically calculated density of states (DOS) of the PF shows semimetallic characteristic, in contrast to metallic nature of FT having non-zero DOS at the bands contact energy. We indicate possibilities for symmetry breaking patterns which correspond to the robustness of the proposed dispersions as well as to the transition from Dirac centrosymmetric semimetal to PF., (© 2020 IOP Publishing Ltd.)

Spin line groups describe the symmetries of spin arrangements in quasi-one-dimensional systems. These groups are derived for the first family of line groups. Among them, magnetic groups are singled out as a special case. Spin arrangements generated by the derived groups are first discussed for single-orbit systems and then the conclusions are extended to multi-orbit cases. The results are illustrated by the examples of a CuO2 zigzag chain, a (13)C nanotube and the hexaferrite Ba2Mg2Fe12O22. Applications to neutron diffraction and classical ground-state determination are indicated.

Optimizations performed with two geometrical, molecular mechanical and density functional models show that the configuration of single-wall carbon nanotubes is slightly twisted with respect to that predicted by conventional techniques. Geometrical models are used to explain the effect by breaking of local symmetry of the equally distant neighbors in graphene in the course of rolling, which is minimized by torsion. The torsion angle is small, and decreases with nanotube diameter, being less than 1° Å(-1) for ultrathin tubes. Therefore this effect can be hard to observe in experiments. Still, we single out features in diffraction patterns which can distinguish between twisted and non-twisted configurations. In addition, torsion makes a blue shift in the radial breathing mode, which for thin tubes can be seen by Raman measurement. The effect is slightly strengthened at room temperature.

Secondary hyperparathyroidism is one of the main and most consistent clinical manifestations of chronic renal failure. It develops in the early stage of chronic renal failure, and its severity increases with further deterioration of renal function. Renal osteodystrophy is the most frequent form of secondary hyperparathyroidism. The management of secondary hyperparathyroidism leads to improvement of calcium and phosphorus homeostasis and suppression of parathyroid secretion. Such treatment with medicament may be unsuccessful, and certain features of secondary hyperparathyroidism may necessitate parathyroid surgery. The aim of this article is to present our experience in the treatment of secondary hyperparathyroidism with subtotal parathyroidectomy. Twenty two patients on haemodialysis after subtotal parathyroidectomy were followed for about 2 years (x +/- SD: 2.0 +/- 1.5) after the operation. During this time the effect of operation on biochemical and clinical signs, and radiographical features of secondary hyperparathyroidism was evaluated. According to our results the subtotal parathyroidectomy stopped in most cases, the progression of secondary hyperparathyroidism. In two patients the reappearance of overt secondary hyperparathyroidism was observed 2.5 and 3.5 years after the operation.

The aim of this study was to investigate in what way the outcome of treatment could be influenced by some traits of personality and its functioning, described in psychological literature as "ego strength". Here, one has to take into account the difficulties in studying the complex process of treatment involving numerous personality and environmental factors, which cannot be separated and observed, measured and assessed as isolated values. Therefore, conclusions about the influence of personality strength on the outcome of treatment have a relevant but not absolute significance. The authors presumed that one of the reasons for the unfavourable outcome of treatment was to be found in the alcoholic's personality system. They tested this presumption on samples of successfully and unsuccessfully treated alcoholics, who received the same treatment, and on a control group. As a measuring instrument for assessing the effectiveness of the personality system, Barron's Ego Strength Scale was used. The study showed that the group of unsuccessfully treated alcoholics had statistically significant lower scores on the ES scale, and that they differed from the successfully treated group. Between successfully treated alcoholics and the control group there were no statistically significant ES Scale differences. The study has indicated that it would be appropriate to use ES Scale before beginning the treatment of alcoholics. Thus in the treatment of those with lower scores, additional attention and activities could be devoted to other systems, those of family and work, within the general system of "man-environment", in order to compensate for the relative inadequacy of the personality system.

The Teffect of haemodialysis on the level of TBG and thyroid hormones in the serum of patients, suffering from terminal form of kidney insufficiency, were investigated. It was established that in the majority of patients euthyroid function of the thyroid gland was preserved. According to our results this preservation of euthyroid function results from the decreased concentration of sera TBG, which follows the decrease of total sera proteins as well as increased peripheral conversion of thyroxine mostly in rT3.

In the treatment of patients with confirmed diabetes mellitus diagnosis and causes of end-stage renal failure represent difficult problems because of their serious systemic complications. There is also disagreement about the advantage of dialysis we have applied. In our Institute over the last five years (until 1986) 20 patients were treated. We analysed the results of 18 patients: 14 on haemodialysis and 4 on intermittent peritoneal dialysis programme at the same time. During haemodialysis treatment the protein condition of the patients was improved and during peritoneal dialysis values of haematocrit and phosphorus. Medical complications were more frequent in the group on peritoneal dialysis. A-V shunt reconstructions were the most common reason of hospitalisation. The most frequent cause of death was hart failure. The survival rate was above the mean values in comparsion to other centres. We are satisfied with the results of treatment of these patients, but we also support the thesis that this is a very risky group of patients. For this moment we cannot adhere to any of these dialysis methods.