Corner transfer matrix renormalization group approach in the zoo of Archimedean lattices.

We develop a new methodology to contract tensor networks within the corner transfer matrix renormalization group approach for a wide range of two-dimensional lattice geometries. We discuss contraction algorithms on the example of triangular, kagome, honeycomb, square-octagon, star, ruby, square-hexagon-dodecahedron, and dice lattices. As benchmark tests, we apply the developed method to the classical Ising model on different lattices and observe a remarkable agreement of the results with the available from the literature. The approach also shows the necessary potential to be applied to various quantum lattice models in a combination with the wave-function variational optimization schemes.

Generation of time-independent torque by ultrasonic guided waves.

The excitation of acoustic waves by a unidirectional transducer, integrated in a piezoelectric cylindrical tube or disk, can lead to a time-independent torque. This phenomenon, demonstrated earlier in experiments and analyzed with coupling-of mode theory, is explained in detail, starting on the level of lattice dynamics of a piezoelectric crystal. Expressions are derived for the stationary torque in the form of integrals over the volume or surface of the piezoelectric, involving the electric potential and displacement field associated with the acoustic waves generated by the transducer. Simulations have been carried out with the help of the finite element method for a tube made of PZT for two cases: A pre-defined potential on the surface of the tube and metal electrodes buried in the piezoelectric. The displacement field and electric potential of the high-frequency acoustic waves (between 200 and 300 kHz) were computed and used in the evaluation of the integrals. The attenuation due to various loss channels of the acoustic waves in the system has been analyzed in detail, as this plays a crucial role for the efficiency of torque generation. It is conjectured that time-reversal symmetry, present in the absence of attenuation, prohibits the generation of a static torque at least in the linear limit. A qualitative comparison is made between the simulations and earlier experiments. Discrepancies are attributed to lack of knowledge of the relevant material constants of the piezoelectric and to a simplified modeling of the electrode geometry in the cylindrical tube, which was necessary for reasons of numerical accuracy.

Diagnostic levels of sepsis biomarkers in children with oncological diseases.

The data on the diagnostic levels of sepsis markers in blood plasma in 117 patients with oncological diseases at the age from 1 to 18 years are presented. The patients were divided into 4 groups depending on the outcome of the clinical course of the inflammatory process or infectious complications: group 1 - patients with no complications of anticancer treatment (n = 13/11.1%), group 2 - the presence of a systemic inflammatory response in patients (n = 64/54.7%), group 3 - patients with sepsis (n = 27/23.1%), group 4 - patients with septic shock (n = 13/11.1%). The threshold level of presepsin between groups 1 and 2 was 202 pg/ml, 371 pg/ml between groups 1 and 3, 604 pg/ml between groups 2 and 3 and 1500 pg/ml between groups 3 and 4. For procalcitonin, the threshold level between groups 1and 2 was 0.23 ng/ml, 0.48 ng/ml between groups 1 and 3, 0.51 ng/ml between groups 2 and 3 and 3.9 ng/ml between groups 3 and 4. The threshold value of C-reactive protein in patients with solid tumors was 12.6 g/l between groups 1 and 2. In patients with oncohematological diseases, the threshold level of C-reactive protein was 43.4 g / L between groups 2 and 3, 77.1 g / L between groups 2 and 4. According to the ROC analysis, presepsin was superior to procalcitonin and C-reactive protein in the diagnosis of septic complications.

Valence band structure and charge distribution in the layered lanthanide-doped CuCr0.99Ln0.01S2 (Ln = La, Ce) solid solutions.

The comprehensive study of the electronic density distribution of CuCr0.99Ln0.01S2 (Ln = La, Ce) solid solutions was carried out using both X-ray photoelectron and emission spectroscopy. It was found that cationic substitution of chromium with lanthanum or cerium atoms does not significantly affect the atomic charges of the matrix elements (Cu, Cr, S) in the lanthanide-doped solid solutions. The copper atoms in the composition of CuCrS2-matrix and the lanthanide-doped solid solutions were found to be in the monovalent state. The chromium and lanthanide atoms were found to be in the trivalent state. This fact indicates the isovalent cationic substitution character. The sulfur atoms were found to be in the divalent state. The near-surface layers contain the additional oxidation forms of sulfur (S0, S4+, S6+) and copper (Cu2+) atoms. The detailed analysis of the valence band structure using DFT calculations has shown that partial DOS distribution character of the matrix elements is preserved after the cationic substitution. The experimental valence band spectra structure of CuCrS2-matrix and CuCr0.99Ln0.01S2 is determined by the occupied copper d-states contribution. The contribution of the lanthanide states in the valence band structure is lower in comparison with those for the matrix elements. The major contribution of the lanthanide states was found to be mainly localized near the conduction band bottom.

[Multiple embolism of arterial vessels of the systemic circulation: classification, clinical manifestations, and outcomes]. / Mnozhestvennye émbolii arterial'nykh sosudov bol'shogo kruga krovoobrashcheniia: klassifikatsiia, klinicheskie proiavleniia, iskhody.

Embologenic arterial obstruction remains an extremely important problem of modern medicine. Emboli may affect virtually all arterial vessels of the greater circulation and in some cases arterial emboli may be multiple. The purpose of the present study was to work out a classification of multiple arterial emboli. Analysing the clinical material including over 30 years a total of 1804 patients with embolism of the aorta and major arteries of the limbs made it possible to define the range of the terms used and to submit for discussion a classification describing a situation where emboli affect simultaneously several arteries or occur repeatedly. Both cases involve several emboli migrating from the primary source into the arterial bed, therefore we suggest that all these emboli be called multiple. Simultaneous multiple emboli were classified as combined, multifocal, and layered, with repeated emboli classified as preceding, recurrent, early and remote. Simultaneous emboli were observed in 91 (5%) patients, of these, in 22 - combined, in 49 - multifocal, in 19 - layered, and in 1 case - combined and multifocal. Repeated emboli were revealed at various terms and encountered virtually in each third patient. Overall mortality amongst the patients with embolism of the aorta and arteries of the limbs over 30 years amounted to 13%, having over the last decade decreased to 7.6%. Multiple arterial emboli significantly influenced the outcomes of treatment, with the mortality rate in combined emboli increasing virtually to 50% and that in multifocal and layered emboli exceeding 20% (p<0.05). Early recurrent emboli in the postoperative period were observed in 6.8% of patients, significantly deteriorating the prognosis (mortality - 49.2%). In the remote period, 22.4% of the patients were operated on for recurrent embolism of arteries of the extremities, with more than 25% of the patients having experienced emboli of cerebral or visceral arteries. Recurrent thromboembolic complications played a significant role in the thanatogenesis in each 4th patient.

[Ultrastructural changes in the endocardium and endocrine cardiomyocytes in the wall of the left atrial appendage in patients with atrial fibrillation]. / Ul'trastrukturnye izmeneniya endokarda i endokrinnykh kardiomiotsitov v stenke levogo ushka bol'nykh s fibrillyatsiei predserdii.

OBJECTIVE: To study ultrastructural changes in endocardial tissues and endocrine cardiomyocytes of the left atrial appendage in patients with atrial fibrillation. MATERIAL AND METHODS: Electron microscopy was used to examine the endocardium and endocrine cardiomyocytes of the left atrial appendage in 8 patients with long-standing paroxysmal and persistent atrial fibrillation and in one patient with coronary heart disease without rhythm disturbance (a control group). RESULTS: The investigation revealed that all the patients with atrial fibrillation had similar ultrastructural changes in all endocardial layers and endocrine cardiomyocytes of the left atrial appendage. The endothelium showed massive desquamation of endothelial cells. Predominantly single sharply flattened cells and small cytoplasmic fragments remained on the endocardial surface. The latter devoid of endothelial coating was represented by subendothelial loose connective tissue with noticeable signs of edema. The latter was also observed in the dense fibrous connective tissue of the endocardium. The accumulation of large amounts of edema fluid in the subendothelium led to endothelial cell flattening and desquamation. There was no leukocytic infiltration in the tissue of the endocardium or fibrin and desquamated endothelial cell accumulation on its surface. The endocrine cardiomyocytes exhibited disorders as cytoplasmic swelling, complete or partial lysis (necrosis) of individual myofibrils, and lower levels of endocrine granules and their location near or in direct contact with the sarcolemma. CONCLUSION: The study has shown that long-standing atrial fibrillation deteriorates the main factors that determine normal endothelial function: edema in subendothelial tissue disrupts its interaction with endothelial cells and leads the latter to detach from the endocardium; ultrastructural changes in the endocrine cardiomyocytes that produce hormones can impair systemic blood pressure control and intracardiac hemodynamics.

[Adiponectin gene expression in local fat depots in patients with coronary heart disease depending on the degree of coronary lesion].

AIM: To determine the dependence of adiponectin gene expression by subcutaneous, epicardial and perivascular adipocytes on the degree of coronary lesion in coronary heart disease. MATERIALS AND METHODS: 84 patients with coronary artery disease were examined. Of these, 39 people showed a moderate degree of atherosclerotic lesion of the coronary bed (less than or equal to 22 points) on the SYNTAX Score scale, 20 severe (2231 points), and 25 extremely severe (more than 32 points). Upon admission to the hospital, all patients underwent an echocardiographic study (Echocardiography, Acuson, Germany) with the calculation of the ejection fraction (EF) of the left ventricle (LV) to assess its systolic function. During a planned surgical intervention (coronary bypass surgery, CABG), adipocytes of subcutaneous, epicardial (EAT) and perivascular adipose tissue (PVAT) were taken. Adiponectin gene expression was evaluated by polymerase chain reaction (real-time PCR) using TaqMan probes. Statistical analysis was performed using Statistica 9.0. RESULTS: The maximum level of adiponectin expression was detected in adipocytes of PVAT, and the minimum EAT. With an increase in the degree of atherosclerotic lesion of the coronary bed, the expression of the adiponectin gene in adipocytes of local depots significantly decreases r=-0.82; p=0.023. Moreover, the low level of gene expression in EAT correlated with a decrease in LV EF by r=0.73; p=0.03. In adipocytes of subcutaneous and especially PVAT, gene expression was the highest in patients with a moderate degree of coronary lesion. CONCLUSIONS: Low adiponectin gene expression in EAT is associated with an increase in the degree of atherosclerotic lesion of the coronary bed and a decrease in LV EF.

[Expression of gene and content of adiponectin in fatty tissue in patients with ischemic heart disease]. / Ékspressiia gena i soderzhanie adiponektina v zhirovoi tkani u patsientov s ishemicheskoi bolezn'iu serdtsa.

The purpose of the study was to investigate the features of expression and adiponectin content in the adipocyte culture of subcutaneous, epicardial, and perivascular adipose tissue and the effect of various doses of rosuvastatin on these processes. 29 patients with coronary artery disease were examined. Adipocytes were isolated from the samples of SAT, EAT and PVAT which were taken during coronary artery bypass surgery, followed by cultivation in the presence of rosuvastatin and evaluation of gene expression and adiponectin concentration. Adipocytes SAT, EAT and PVAT differed in the level of adiponectin secretion and expression of its gene. On day 1 of cultivation the expression of the adiponectin gene in the EAT was 2.3 times lower than in the PVAT. On day 2 of cultivation the expression of the adiponectin gene was reduced both in the EAT and the PVAT as compared to the SAT. When rosuvastatin was added at a concentration of 1 mmol/L, adiponectin gene expression in PVAT was higher than when rosuvastatin was added at a concentration of 5 mmol/L, in the adipocyte culture of SAT effect was opposite. Thus, the adipocytes of EZhT and, to a greater extent, PAS, can be a therapeutic target for statins in the case of the pathological activation of adipose tissue.

[Lifespan of patients after endured embolism of the aorta and major arteries of the limbs]. / Prodolzhitel'nost' zhizni bol'nykh, perenesshikh émbolii aorty i magistral'nykh arterii konechnostei.

The authors analysed the remote results of treatment of patients having endured embologenic arterial obstruction. Over the last 47 years, specialists of the Department of Cardiovascular Surgery No1 of the North-Western State Medical University named after I.I. Mechnikov have rendered emergency medical care to a total of 3,455 patients presenting with embolisms of the aorta and arteries of the limbs. The remote results of treatment were followed up in 978 patients within the terms varying from 1 year to 30 years. The cumulative survival of patients at 1 year of follow up amounted to 72±2.9%, at 2 years to 55±3.3%, at 3 years to 46.1±3.3%, at 5 years to 33.5±3.4%, and at 10 years to only 17.8±3.8%. The subanalysis of the remote results of treatment of patients having sustained arterial embolisms was carried out in three groups of patients, depending on the character of the underlying disease. In patients of the 1st group, the development of arterial embolism was caused by atrial fibrillation of non-valvular aetiology, taking course on the background of hypertensive disease, IHD. The cumulative survival of patients of this group at 1 year of follow up amounted to 66.6±4.5%, at 3 years to 37.5±4.8%, at 5 years to 23.1±4.9% and at 10 years to less than 6%. Death was caused by progressing cardiovascular insufficiency in more than 60% of patients, by acute myocardial infarction in nearly 20% of cases and in 10% by impairment of cerebral circulation. In patients of the 2nd group, arterial embolisms were the consequences of endured infarction; their cumulative survival at 1 year of follow up amounted to 70.1±6.5%, at 3 years to 34.5±7.1%, at 5 years to 23.6±6.6%, and at 10 years to 12.5±6.5%. Patients of the 3rd group suffered from acquired heart valve disease of rheumatic aetiology, with the cumulative survival at 1 year amounting to 76.8±5.4%, at 3 years to 56.3±6.4%, at 5 years to 43.3±6.7% and at 10 years to 19.6±6.9%. In the thanatogenesis of more than 60% of patients there were thromboembolic complications, with progressing cardiac insufficiency present in nearly 30% of cases. The pattern of the remote results of treatment of patients with embolisms of the aorta and arteries of the limbs is strongly suggestive of the necessity of working out a comprehensive programme of medical rehabilitation.

Theoretical investigation of excitonic magnetism in LaSrCoO4.

We use the LDA+U approach to search for possible ordered ground states of LaSrCoO4. We find a staggered arrangement of magnetic multipoles to be stable over a broad range of Co 3d interaction parameters. This ordered state can be described as a spin-density-wave-type condensate of [Formula: see text] excitons carrying spin S = 1. Further, we construct an effective strong-coupling model, calculate the exciton dispersion and investigate closing of the exciton gap, which marks the exciton condensation instability. Comparing the layered LaSrCoO4 with its pseudo cubic analog LaCoO3, we find that for the same interaction parameters the excitonic gap is smaller (possibly vanishing) in the layered cobaltite.

Field-induced exciton condensation in LaCoO3.

Motivated by recent observation of magnetic field induced transition in LaCoO3 we study the effect of external field in systems close to instabilities towards spin-state ordering and exciton condensation. We show that, while in both cases the transition can be induced by an external field, temperature dependencies of the critical field have opposite slopes. Based on this result we argue that the experimental observations select the exciton condensation scenario. We show that such condensation is possible due to high mobility of the intermediate spin excitations. The estimated width of the corresponding dispersion is large enough to overrule the order of atomic multiplets and to make the intermediate spin excitation propagating with a specific wave vector the lowest excitation of the system.

[Use of spectral index of heart rate variability as a predictor of poor clinical outcome in patients with severe combined chest trauma].

Use of spectral index of heart rate variability as a predictor of poor clinical outcome in patients with severe combined chest trauma. The article provides information on results of research of connection between spectral index of heart rate variability, got during 5-minutes record of echocardiography in acute period of traumatic disease, and severity of trauma, severity of health condition and level of impairment of consciousness in patients with combined chest trauma. Defined correlating connections between separate indexes of spectral analysis of heart rate variability and scales, reflecting health status severity and severity of trauma when admission the patients. Defined accurate differences between indexes of a power of very low frequency, low frequency and high-frequency waves, indexes of a vagosympathetic balance in groups of patients with poor clinical outcome and lethal outcome. Proved the possibility of the use of definite, during 12 hours after getting injury, relative powers of low- frequency and high-frequency waves, expressed in normalized units, index of a vagosympathetic balance as physiological markers of poor clinical outcome in patients with severe combined chest trauma.

[Hashimoto's encephalopathy].

Hashimoto's encephalopathy is an autoimmune inflammatory disease of the brain associated with the production of antithyoid antibodies. The case described in this article illustrates the diversity of clinical presentations of the disease that mimic symptoms of some neurological and mental disorders, difficulties of diagnosis and, at the same time, the importance of the timely diagnosis of this severe but curable disease. Diagnostic criteria of encephalopathy allowing the avoidance of both hypo- and hyper diagnosis of this disease are considered. The authors present the current tactics of its treatment based on the use of corticosteroids and other immunotropic drugs.

[Morphometric characteristics of the hemomicrocirculatory bed vessels in rat colon in large bowel obstruction and after its resolution].

The results are presented that describe the experimental study of colonic hemomicrocirculatory bed (HMCB) in intact rats, in animals 6 days after large bowel obstruction development that was modeled using the device created by the authors, and 1-15 days after its resolution. The most significant changes were observed in the capillaries and HMCB venular portion--capillary diameter was increased by 60-100%, while that of venules--by 73% as compared to those in control group. The degree of changes depended on the distance from the extraorgan bowel compression site. The dynamics of the normalization of morphometric parameters after colon obstruction resolution was demonstrated. It was found that the average arteriolar and venular diameters reached the initial level by day 5, while that of the capillaries by day 7 after colon obstruction resolution.

[Risk factors for myocardial infarction recurrence in young and middle-aged males].

AIM: To assess a set of risk factors (RF) for coronary heart disease in myocardial reinfarction patients aged less than 60 years. SUBJECTS AND METHODS: A multitude of probable RFs that might predispose to the development of MI or provoke its occurrence were studied in 526 male patients aged less than 60 years, who had primary (n = 281) and repeated (n = 245) myocardial infarction (MI) from the results of hospital treatment. RESULTS: Lipid metabolic disturbances, smoking, arterial hypertension (AH), foci of chronic infection, and overweight were ascertained to be the most common RFs in patients less than 60 years. There was a history of dyslipidemia (100%), AH, heart failure, and cardiac arrhythmias in the complicated course of repeated MI. When these RFs are combined, the likelihood of disease complications and death increases. CONCLUSION: According to the results of estimation of the spread of RFs for myocardial reinfarction, it is proposed to enhance the monitoring of lipidogram readings, blood pressure value, magnitude of the symptoms of heart failure, and serum glucose levels, and infection foci sanitization and to improve patients' awareness about a risk from smoking and lower physical activity.

[Specific features of myocardial infarction in young and middle-aged subjects].

The aim of the study was to obtain an insight into the origin and specific features of myocardial infarction (MI) in 322 subjects below 60 yr of age. Most patients had anginous complaints. The incidence of non-anginous forms of MI in patients aged below 45 and 46-60 years was estimated with reference to the occurrence of complications. The structure of these complications and causes of their fatal outcome were elucidated. The prevalence of risk factors of MI in the survivors and patients who died was obtained.

[Polyposis of the stomach. Endoscopic treatment or follow-up?].

Out of 3243 patients with gastric polips, polyposis was diagnosed in 298 ones including 135 cases of complicated and 163 cases of uncomplicated forms. Hyperplastic polips were diagnosed in 281 patients. Along with hyperplastic polyps, solitary adenomas were diagnosed in 9 cases, Peitz-Jegerc polyps - in 6, and juvenile polyps - in 2. Polypectomy was performed in 153 patients: partial - in 104, and total - in 49. Follow-up was carried out in 98 non-operated patients, indications for endoscopic surgery were seen in 18 cases. After partial endoscopic polypectomy, repolypectomy was performed in 24 cases: single - in 8, multiple - in 16. Repeated endoscopic treatment after total polypectomy was performed in 3 patients. There were no cases of polyp transformation into cancer. Open surgical treatment was not performed. There were no severe complications after endoscopic treatment.

[Prognostic value of SAPS II and APACHE II scales in patients with multiple organ failure syndrome during early postoperative period after oncological surgery]. / Prognosticheskoe znachenie shkal SAPS II i APACHE II u bol'nykh s sindromom poliorgannoi nedostatochnosti rannego posleoperatsionnogo perioda posle onkokhirurgicheskikh vmeshatel'stv.

The key fixed task was the following: detection, as soon as possible, of patients with a high risk of lethal outcome; an objective assessment of the condition of patients during the early postoperative period by using a quantitative evaluation (SAPS II, APACHE II); and defining of the prognostic value of SAPS II and APACHE II after oncology surgeries. The in-hospital lethality amounted to 53% in 73 patients with MOFS during the early postoperative period after oncology surgeries. The formalized (numerical) score, according to SAPS II and APACHE II, made it possible to detect patients with a higher risk of lethal outcome yet during the very first day after oncology surgeries. If the score of SAPS II or APACHE II topped 30 (on the first day after surgery), then the in-hospital lethality exceeded 50%. The information density of the SAPS II and APACHE II systems turned out to be identical, however, SAPS II appears to be more convenient in terms of practical usage since it demands the evolution of a smaller number of physiological parameters.

Structure and properties of confined sodium nitrite.

The temperature evolution of the structure of NaNO(2) nanocomposite ferroelectric material in a porous glass with 7 nm pores was studied by neutron diffraction in temperature region from room temperature up to the melting, i.e. in the ferro- and paraelectric phases. It is demonstrated that in the ferroelectric phase the structure is consistent with the structure of the bulk, but above the ferroelectric phase transition (and up to approximately 513 K) a volume premelted state is formed, manifesting itself in a growth of amplitudes of ion thermal vibrations, a steep increase of elementary cell volume and "softening" of lattice. For the first time the temperature dependence of order parameter eta for confined sodium nitrite is determined. eta (T) follows a power law with T(C)=425.6+/- 2.1 K and beta= 0.31+/- 0.04, which is essentially different from that for bulk NaNO(2). Our obtained data are in a good agreement with the results of earlier dielectric and neutron diffraction measurements.