Phonon Topology and Winding of Spectral Weight in Graphite.

The topology of electronic and phonon band structures of graphene is well studied and known to exhibit a Dirac cone at the K point of the Brillouin zone. Here, we applied inelastic x-ray scattering (IXS) along with ab initio calculations to investigate phonon topology in graphite, the 3D analog of graphene. We identified a pair of modes that form a very weakly gapped linear anticrossing at the K point that can be essentially viewed as a Dirac cone approximant. The IXS intensity in the vicinity of the quasi-Dirac point reveals a harmonic modulation of the phonon spectral weight above and below the Dirac energy, which was previously proposed as an experimental fingerprint of the nontrivial topology. We illustrate how the topological winding of IXS intensity can be understood in terms of atomic displacements and highlight that the intensity winding is not in fact sensitive in telling quasi- and true Dirac points apart.

19F electron nuclear double resonance (ENDOR) spectroscopy for distance measurements using trityl spin labels in DNA duplexes.

The combination of fluorine labeling and pulsed electron-nuclear double resonance (ENDOR) is emerging as a powerful technique for obtaining structural information about proteins and nucleic acids. In this work, we explored the capability of Mims 19F ENDOR experiments on reporting intermolecular distances in trityl- and 19F-labeled DNA duplexes at three electron paramagnetic resonance (EPR) frequencies (34, 94, and 263 GHz). For spin labeling, we used the hydrophobic Finland trityl radical and hydrophilic OX063 trityl radical. Fluorine labels were introduced into two positions of a DNA oligonucleotide. The results indicated that hyperfine splittings visible in the ENDOR spectra are consistent with the most populated interspin distances between 19F and the trityl radical predicted from molecular dynamic (MD) simulations. Moreover, for some cases, ENDOR spectral simulations based on MD results were able to reproduce the conformational distribution reflected in the experimental ENDOR line broadening. Additionally, MD simulations provided more detailed information about the melting of terminal base pairs of the oligonucleotides and about the configuration of the trityls relative to a DNA end.

Application of W-band 19F electron nuclear double resonance (ENDOR) spectroscopy to distance measurement using a trityl spin probe and a fluorine label.

Recently, Marina Bennati and coworkers (M. Bennati et al., Angew. Chem., Int. Ed., 2020, 59, 373-379., M. Bennati et al., J. Magn. Reson., 2021, 333, 107091) proposed to use electron nuclear double resonance (ENDOR) spectroscopy in the W-band for a pair of labels, nitroxide and 19F, for measurements of short (0.5-1.0 nm) distances in biomolecules. In our paper, we investigated the suitability of high-field ENDOR spectroscopy in the W-band for pairs of triarylmethyl and fluorine labels using five newly synthesized model compounds. It is shown that the application of strong magnetic fields allows distinguishing nuclear frequencies of 19F and protons with sufficient resolution. On the one hand, in contrast to nitroxides, for triarylmethyl radicals, it is not necessary to obtain spectra in different orientations owing to low g-factor anisotropic and long electron spin relaxation times of triarylmethyls. On the other hand, the size of the triarylmethyl radical is substantially larger than that of nitroxide and comparable with measured distances. We theoretically analyzed the suitability of the dipole-dipole approach for triarylmethyl to be used in a 19F ENDOR experiment and determined limitations of this approach. Finally, for comparison, we performed paramagnetic relaxation enhancement (PRE) NMR on the same compounds. In addition, we applied this approach to study the process of a thiol exchange between molecules of triarylmethyl-labeled and 19F-labeled human serum albumin (HSA).

[Metabolic syndrome is a risk factor for cognitive impairment among older participants of the groups of health.]

The aim of this study is to evaluate the influence of the metabolic syndrome components (MetS) on cognitive impairment (CI) in groups of health by the logistic regression with the construction of multivariate probabilistic models. This study was based on the continuous series of groups of health at the Novosibirsk Gerontological center and involved 305 aged participants. This group consisted from 31 men (10,2%) and 274 women (89,8%); the average age of men was 71,42±7,21, in women 67,45±7,62. The diagnosis of MetS was carried out in accordance with the recommendations of IDF and AHA/NHLBI consensus. The diagnosis of CI was performed using the «Mini-Cog¼ test. The statistical analysis was carried out using the «R for Windows¼ freeware package. Multivariate analysis using logistic regression was performed to evaluate the effects of various factors. During adjustment for confounding factors at groups of health, the statistically significant associations between the MetS components and CI in the elderly were detected. The following predictors were statistically significant in the logistic regression model: serum glucose concentration (p=0,01), waist circumference (p=0,026), hip circumference (p<0,0001), and age (p<0,0001). The relationship between the MetS components and CI confirms importance of the «cerebrovascular continuum¼ hypothesis in the cognitive disorders onset, as well as the close associations between the somatic and the mental compo-nents at the aged people. Among the elderly, it is necessary to promote healthy life-styles and more active participation in groups of health.

[Experience of treatment of pancreatonecrosis in hospital in the extreme north].

Criteria of pancreatonecrosis are described in the article. Clinical and ultrasonic signs, the applied ways of treatment of acute pancreatitis are considered in 715 patients. The methods of treatment of complications of pancreatonecrosis are described. The lethality of the patients with pancreatonecrosis was 13.2% and between operated patients--16.4%. The lethality was 2.8% in the group of patients with pancreatitis.

Adherence of the rotating vortex lattice in the noncentrosymmetric superconductor Ru7B3to the London model.

The noncentrosymmetric superconductor Ru7B3has in previous studies demonstrated remarkably unusual behaviour in its vortex lattice (VL), where the nearest neighbour directions of the vortices dissociate from the crystal lattice and instead show a complex field-history dependence, and the VL rotates as the field is changed. In this study, we look at the VL form factor of Ru7B3during this field-history dependence, to check for deviations from established models, such as the London model. We find that the data is well described by the anisotropic London model, which is in accordance with theoretical predictions that the alterations to the structure of the vortices due to broken inversion symmetry should be small. From this, we also extract values for the penetration depth and coherence length.

[Unsaturated fatty acids as a preventive measure for Alzheimer's disease: the literature review].

This article presents the using of omega-3 unsaturated fatty acids (docosahexaenoic and eicosapentaenoic acid) as a possible preventive measure for Alzheimer's disease on the basis of modern literature data. It is possible to use the combination of the anticholinesterase drugs and the omega-3 unsaturated fatty acids.

Structure and magnetic properties of nanostructured Pd-Fe thin films produced by pulse electrodeposition.

Nanostructured Pd-Fe thin films with varied Fe content were prepared by electrodeposition technique from organic electrolytes on Cu and brass substrates. The structure and the magnetic properties of the films were investigated prior to post-deposition annealing. The structure of the Pd1-xFe(x) thin film with x = 0.14, 0.24, and 0.52 was determined by X-ray diffraction (XRD) and transmission electron microscopy (TEM) as a solid solution of iron in palladium face-centered cubic lattice with the (111) orientation of nanograins relatively to the substrate surface. The films with higher iron concentration, x = 0.74, 0.91, have structure of a solid solution based on the body-centered cubic lattice. The average grain size determined by the scanning electron microscopy (SEM) for the first two alloys is 7-10 nm, and for the latter ones it is about 120 nm. The saturation magnetization of the films has linear dependence on the iron content, but coercivity has non-monotonic dependence on x, i.e., the films with x = 0.68 show highest coercivity. The magnetic anisotropy of the samples is studied by ferromagnetic resonance (FMR) spectroscopy.

[Comparison of various diagnostic methods of Helicobacter infection].

PURPOSE OF INVESTIGATION: There has been conducted comparison of the most wide-spread methods of diagnosis of Helicobacter pylori infection: histologic, cytologic, method of polymerase chain reaction (PMCR) and respiratory urease Xelic-test on the method of AMA firm. MATERIALS AND METHODS: 1118 patients participated in the investigation, 403 patients were investigated by urease test and 50 ones were investigated by method of PMCR. The results of investigations were compared by means of correlative and variational analysis. RESULTS: There has been shown fine comprison of histologic, cytologic methods of Helicobacter pylori revealing and PMCR method both between them (coefficients of correlation 0.79, 0.34 and 0.53 accordingly), and with indices of gastritis activity (coefficients of correlation 0.49, 0.52 and 0.37 accordingly). On the other hand the results of respiratory urease Xelic-test did not correspond to any of investigated indices (coefficients of correlation 0.02, 0.05 and 0.09). The possible causes of such discrepancy, based on features of chemical properties of ammonia have been defined. Except known reaction of neutralization with hydrochloric acid, ammonia able to show donor-acceptor interactions and form various compounds with organic substances. CONCLUSION: Urease respiratory Xelic-test on the method of AMA firm can not be used for definition of Helicobacter pylori infection.

Multiple fermion scattering in the weakly coupled spin-chain compound YbAlO3.

The Heisenberg antiferromagnetic spin-1/2 chain, originally introduced almost a century ago, is one of the best studied models in quantum mechanics due to its exact solution, but nevertheless it continues to present new discoveries. Its low-energy physics is described by the Tomonaga-Luttinger liquid of spinless fermions, similar to the conduction electrons in one-dimensional metals. In this work we investigate the Heisenberg spin-chain compound YbAlO3 and show that the weak interchain coupling causes Umklapp scattering between the left- and right-moving fermions and stabilizes an incommensurate spin-density wave order at q = 2kF under finite magnetic fields. These Umklapp processes open a route to multiple coherent scattering of fermions, which results in the formation of satellites at integer multiples of the incommensurate fundamental wavevector Q = nq. Our work provides surprising and profound insight into bandstructure control for emergent fermions in quantum materials, and shows how neutron diffraction can be applied to investigate the phenomenon of coherent multiple scattering in metals through the proxy of quantum magnetic systems.

Event-by-event fluctuations of azimuthal particle anisotropy in Au+Au collisions at square root(sNN) = 200 GeV.

This Letter presents the first measurement of event-by-event fluctuations of the elliptic flow parameter v(2) in Au+Au collisions at square root(s(NN))=200 GeV as a function of collision centrality. The relative nonstatistical fluctuations of the v(2) parameter are found to be approximately 40%. The results, including contributions from event-by-event elliptic flow fluctuations and from azimuthal correlations that are unrelated to the reaction plane (nonflow correlations), establish an upper limit on the magnitude of underlying elliptic flow fluctuations. This limit is consistent with predictions based on spatial fluctuations of the participating nucleons in the initial nuclear overlap region. These results provide important constraints on models of the initial state and hydrodynamic evolution of relativistic heavy ion collisions.

High transverse momentum triggered correlations over a large pseudorapidity acceptance in Au + Au collisions at square root(s(NN)) = 200 GeV.

A measurement of two-particle correlations with a high transverse momentum trigger particle (p(T)(trig) > 2.5 GeV/c) is presented for Au+Au collisions at square root(s(NN)) = 200 GeV over the uniquely broad longitudinal acceptance of the PHOBOS detector (-4 < Delta eta < 2). A broadening of the away-side azimuthal correlation compared to elementary collisions is observed at all Delta eta. As in p+p collisions, the near side is characterized by a peak of correlated partners at small angle relative to the trigger particle. However, in central Au+Au collisions an additional correlation extended in Delta eta and known as the "ridge" is found to reach at least |Delta eta| approximately = 4. The ridge yield is largely independent of Delta eta over the measured range, and it decreases towards more peripheral collisions. For the chosen (p(T)(trig) cut, the ridge yield is consistent with zero for events with less than roughly 100 participating nucleons.

[Peculiarities of face regional hemodynamics in treatment of acute purulent jaw odontogenic periostitis].

53 patients were under observation with acute purulent jaw odontogenic periostitis. In 27 out of them after operation as drainage material strips of napkin were used, containing as the active components metronidazol, dimexide and sodium alginate. Curative process efficacy evaluation was done according to the data of hemodynamic study (determination of the artery's diameter, maximal systolic speed and index of circulatory resistance) of the magistral face arteries. It was established that in the group of patients with rational treatment blood circulation in face arterial vessels was restored most actively than in the control group with the use of traditional treatment scheme.

[Delayed results of proximal gastrectomy in patients with esophageal and gastric varices].

An original method of proximal gastrectomy was used to eliminate hemorrhage from gastric and oesophagal varicose veins in 27 patients with portal hypertension. The follow up period varied from 1 to 23 years. The risk of hemorrhage and the degree of vein dilatation were assessed by endoscopy and endoscopic ultrasonography. It is concluded that the method used in the study may be recommended as the first-line surgery for the management of hemorrhage from gastric and oesophagal varicose veins with good functional results in the late postoperative period and rare complications.

[Koletex-M absorbent paper use in acute festering odontogenic periostitis treatment].

150 patients with acute festering odontogenic periostitis were under observation. In 75 of them Koletex-M absorbent paper was used as draining material containing as active components metronidazole, dimexide and sodium alginate. In the control group of patients traditional schemes of treatment were used. Treatment process efficacy was estimated by microbiological and cytological studies. It was found that Koletex-M absorbent paper use reduced postoperative wound microbe semination. In 3 days the cells of regenerative series were found that led to speedy wound healing and reduction of temporary disability terms.

[Rapidly progressive glomerulonephritis in ANCA-associated vasculitis: a course, treatment efficacy, prognosis].

AIM: To study efficacy of ANCA-RPGN treatment with corticosteroids and cyclophosphamide or mycophenolic acid drugs. MATERIAL AND METHODS: We treated 28 patients (17 males and 11 females aged 19-71 years) with morphologically verified ANCA-associated crescentic RPGN (crescentic median 79 (63:88)%. The patients received corticosteroids and cytostatics. RESULTS: The response to the treatment was registered in 22 (78%) patients in 8-16 weeks: a complete remission was achieved in 8 patients, a partial one--in 14 patients. In partial remission renal functions recovered incompletely (median Pcr 200 (180;255) mcmol/l) in persistence of moderate proteinuria (median 0.7 (0.6;1.3)g/day) and absence of microhematuria. Probability of the treatment success depended on severity of glomerulosclerosis and weakly depended on activity of extracapillary reaction. Severe renal failure was not an absolute predictor of treatment failure. CONCLUSION: In the absence of advanced nephrosclerosis early treatment with corticosteroid in combination with cytostatics can produce a positive effect in 70-80% patients with ANCA associated RPGN.

Crystal environment of impurity Nd3+ ion in yttrium and scandium orthosilicate crystals.

The ESEEM spectroscopy was used to determine positions of the 143Nd3+ impurity ions in Y2SiO5 single crystal. It is established that neodymium ions substitute yttrium ions in the Y2 positions with seven nearest oxygen ions. Crystal field parameters of 143Nd3+ impurity centers in isotopically pure Y228SiO5 and Sc228SiO5 single crystals were determined using data of CW EPR spectroscopy and the known energy level schemes.

Thermal expansion of monogermanides of 3d-metals.

Temperature dependent powder and single-crystal synchrotron diffraction, specific heat, magnetic susceptibility and small-angle neutron scattering experiments have revealed an anomalous response of MnGe. The anomaly becomes smeared out with decreasing Mn content in Mn1-x Co x Ge and Mn1-x Fe x Ge solid solutions. Mn spin state instability is discussed as a possible candidate for the observed effects.

[Molecular mobility and electrical properties of keratin]. / Molekuliarnaia podvizhnost' i élektretnye svoistva keratina.

The samples made from the horn of Saiga tatarica were investigated by PMR method. It was shown that an increase of mobility of adsorbed molecules correlated with the appearance of the peaks of thermally stimulated currents of depolarization in the region of 370 K-390 K. The activation energies of molecular mobility in keratin were found.