Single-particle and collective excitations of polar water molecules confined in nano-pores within a cordierite crystal lattice.

Recently, the low-temperature phase of water molecules confined within nanocages formed by the crystalline lattice of water-containing cordierite crystals has been reported to comprise domains with ferroelectrically ordered dipoles within the a, b-planes which are antiferroelectrically alternating along the c-axis. In the present work, comprehensive broad-band dielectric spectroscopy is combined with specific heat studies and molecular dynamics and Monte Carlo simulations in order to investigate in more detail the collective modes and single-particle excitations of nanoconfined water molecules. From DFT-MD simulations we reconstruct the potential-energy landscape experienced by the H2O molecules. A rich set of anisotropic temperature-dependent excitations is observed in the terahertz frequency range. Their origin is associated with the complex rotational/translational vibrations of confined H2O molecules. A strongly temperature dependent relaxational excitation, observed at radio-microwave frequencies for the electric field parallel to the crystallographic a-axis, E||a is analyzed in detail. The temperature dependences of loss-peak frequency and dielectric strength of the excitation together with specific heat data confirm a ferroelectric order-disorder phase transition at T0 ≈ 3 K in the network of H2O dipoles. Additional dielectric data are also provided for polarization E||b, too. Overall, these combined experimental investigations enable detailed conclusions concerning the dynamics of the confined water molecules that develop within their microscopic energy landscapes.

Excitation of localized graphene plasmons by aperiodic self-assembled arrays of metallic antennas.

Infrared (IR) and terahertz plasmons in two-dimensional (2D) materials are commonly excited by metallic or dielectric grating couplers with deep-submicron features fabricated by e-beam lithography. Mass reproduction of such gratings at macroscopic scales is a labor-consuming and expensive technology. Here, we show that localized plasmons in graphene can be generated on macroscopic scales with couplers based on randomly oriented particle-like nanorods (NRs) in close proximity to graphene layer. We monitor the excitation of graphene plasmons indirectly by tracking the changes in reflection/absorption spectra of methylene blue (MB) or polymethyl methacrylate(PMMA) molecules deposited on the structure. Hybridization of spectrally broad graphene plasmon and narrow molecular oscillators results in enhanced oscillator strengths and Fano scattering related lines asymmetry in reflection spectra.

Quantum spin liquids unveil the genuine Mott state.

The localization of charge carriers by electronic repulsion was suggested by Mott in the 1930s to explain the insulating state observed in supposedly metallic NiO. The Mott metal-insulator transition has been subject of intense investigations ever since1-3-not least for its relation to high-temperature superconductivity4. A detailed comparison to real materials, however, is lacking because the pristine Mott state is commonly obscured by antiferromagnetism and a complicated band structure. Here we study organic quantum spin liquids, prototype realizations of the single-band Hubbard model in the absence of magnetic order. Mapping the Hubbard bands by optical spectroscopy provides an absolute measure of the interaction strength and bandwidth-the crucial parameters that enter calculations. In this way, we advance beyond conventional temperature-pressure plots and quantitatively compose a generic phase diagram for all genuine Mott insulators based on the absolute strength of the electronic correlations. We also identify metallic quantum fluctuations as a precursor of the Mott insulator-metal transition, previously predicted but never observed. Our results suggest that all relevant phenomena in the phase diagram scale with the Coulomb repulsion U, which provides a direct link to unconventional superconductivity in cuprates and other strongly correlated materials.

Low-Energy Excitations in Quantum Spin Liquids Identified by Optical Spectroscopy.

The electrodynamic response of organic spin liquids with highly frustrated triangular lattices has been measured in a wide energy range. While the overall optical spectra of these Mott insulators are governed by transitions between the Hubbard bands, distinct in-gap excitations can be identified at low temperatures and frequencies, which we attribute to the quantum-spin-liquid state. For the strongly correlated ß^{'}-EtMe_{3}Sb[Pd(dmit)_{2}]_{2}, we discover enhanced conductivity below 175 cm^{-1}, comparable to the energy of the magnetic coupling J≈250 K. For ω→0, these low-frequency excitations vanish faster than the charge-carrier response subject to Mott-Hubbard correlations, resulting in a dome-shaped band peaked at 100 cm^{-1}. Possible relations to spinons, magnons, and disorder are discussed.

Terahertz-infrared spectroscopy of Shewanella oneidensis MR-1 extracellular matrix.

Employing optical spectroscopy we have performed a comparative study of the dielectric response of extracellular matrix and filaments of electrogenic bacteria Shewanella oneidensis MR-1, cytochrome c, and bovine serum albumin. Combining infrared transmission measurements on thin layers with data of the terahertz spectra, we obtain the dielectric permittivity and AC conductivity spectra of the materials in a broad frequency band from a few cm-1 up to 7000 cm-1 in the temperature range from 5 to 300 K. Strong absorption bands are observed in the three materials that cover the range from 10 to 300 cm-1 and mainly determine the terahertz absorption. When cooled down to liquid helium temperatures, the bands in Shewanella oneidensis MR-1 and cytochrome c reveal a distinct fine structure. In all three materials, we identify the presence of liquid bound water in the form of librational and translational absorption bands at ≈ 200 and ≈ 600 cm-1, respectively. The sharp excitations seen above 1000 cm-1 are assigned to intramolecular vibrations.

[The hardware techniques for the restoration of the gait stereotype in the patients following total hip replacement: the personalized approach].

BACKGROUND: total hip replacement has long ago become the «golden standard¼ for the treatment of dysplastic coxarthrosis in thousands of the patients receiving it every year. In the meantime, the analysis of the specialized literature gives evidence of the lack of a systematic and personified approach to the rehabilitation treatment. AIM: The objective of the present study was to improve medical rehabilitation of the patients following the total hip replacement and to develop the personalized programs for walking modality reconstruction taking into consideration the age and the body weight of the patients. PATIENTS AND METHODS: A total of 240 patients were available for the observation including 184 women and 56 men. They were divided into three study groups and one control group, with the differentiation into the following three subgroups: one comprised of the patients of moderate acerage age and body weight, the other containing the obese patients (BMI>35), and the third one involving the elderly patients (age >70 years); each subgroup consisted of 20 patients. All the patients received the early basic rehabilitation treatment, those in the study groups had to perform in addition the robotic training based on the use of hardware techniques supplemented by passive mechanotherapy and electromyostimulation designed to restore the walking stereotype with three types of devices: body weight unloading, video-reconstruction associated with biological feedback and robototherapy. RESULTS: The comparative analysis of the effectiveness of various methods of gait reconstruction has demonstrated the high effectiveness of the application of the hardware technique in the patients of moderate acerage age and body weight. At the same time, the elderly patients had a significantly higher rate of successful walking reconstruction efficiency under the influence of the video-associated training with biological feedback (3 times that achieved with training using the device for unloading the body weight and 4 times compared with the result of a course of robotic walk. The evaluation of the application of the techniques for the gait stereotype reconstruction in the obese patients gave evidence of the advantage of the Lokomat robotic trainings that produced 6 times better results than unloading of the body weight and 5 times better ones than the video-associated training with biological feedback. DISCUSSION: The results of the present study are on the whole comparable with the data reported by other authors although its design was different from that of the majority of the published studies in that our patients were allocated to different subgroups for the further personalization of the methods applied to restore the gait stereotype. The factors limiting the use of the results of this study include the medium-high level of the patients' welfare most of whom are residents of the city of Moscow and Moscow region characterized by a relatively high quality and accessibility of health care. It means that the results of such studies as the one described in the present article are directly related to the quality and accessibility of health care and can be extrapolated only to the socially safe and well-to-do patients. CONCLUSIONS: All the hardware techniques are equally effective in the patients of moderate average age and body weight. The elderly patients showed the best results using the video-reconstruction associated with biological feedback, while the Locomat technique was especially useful for the obese patients.

Terahertz-infrared electrodynamics of single-wall carbon nanotube films.

Broad-band (4-20 000 cm-1) spectra of real and imaginary conductance of a set of high-quality pristine and AuCl3-doped single-walled carbon nanotube (SWCNT) films with different transparency are systematically measured. It is shown that while the high-energy (≥1 eV) response is determined by well-known interband transitions, the lower-energy electrodynamic properties of the films are fully dominated by unbound charge carriers. Their main spectral effect is seen as the free-carrier Drude-type contribution. Partial localization of these carriers leads to a weak plasmon resonance around 100 cm-1. At the lowest frequencies, below 10 cm-1, a gap-like feature is detected whose origin is associated with the energy barrier experienced by the carriers at the intersections between SWCNTs. It is assumed that these three mechanisms are universal and determine the low-frequency terahertz-infrared electrodynamics of SWCNT wafer-scale films.

Vibrational states of nano-confined water molecules in beryl investigated by first-principles calculations and optical experiments.

Using quantum mechanical calculations within density functional theory, we provide a comprehensive analysis of infrared-active excitation of water molecules confined in nanocages of a beryl crystal lattice. We calculate infrared-active modes including the translational, librational, and mixed-type resonances of regular and heavy water molecules. The results are compared to the experimental spectra measured for the two principal polarizations of the electric field: parallel and perpendicular to the crystallographic c-axis. Good agreement is achieved between calculated and measured isotopic shifts of the normal modes. We analyze the vibrational modes in connection with the structural characteristics and arrangements of water molecules within the beryl crystal. Specific atomic displacements are assigned to each experimentally detected vibrational mode resolving the properties of nano-confined water on scales not accessible by experiments. Our results elucidate the applicability and efficiency of a combined experimental and computational approach for describing and an in-depth understanding of nano-confined water, and pave the way for future studies of more complex systems.

Changes in Production of Cytokines by C57Bl/6J Mouse Spleen during Aggression Provoked by Social Stress.

The effect of aggressive behavior shaped under social stress of various durations on the production of proinflammatory cytokines by splenic cells was examined on C57BL/6J mice. Aggressive mice were characterized by enhanced production of IL-2 and IFN-γ (released by T helper type 1 cells) and reduced secretion of TNF-α, whose major producers are monocytes and macrophages. Elevation of IL-2 and IFN-γ in aggressive mice resulted from enhancement of spontaneous and Con A-stimulated production, the most pronounced effect was demonstrated by the with a longer period (20 days) of victories. In contrast, spontaneous production of TNF-α was similar in control and aggressive mice, although LPS-stimulated production of this cytokine decreased after 10- and 20-day stress. The possible mechanisms of the changes in cytokine production are discussed.

Comparative evaluation of opioid-induced changes in immune reactivity of CBA mice.

Comparison of IgM and IgG-humoral immune response of CBA mice immunized with SE (5 × 10(8) cells) to activation of µ- (DAGO, 100 µg/kg) and δ2- (DSLET, 100 µg/kg) opioid receptors was studied. Different effects of opioids on IgM and IgG antibody production and peripheral blood and spleen levels of CD4(+) and CD8(+) subpopulations were detected at the peak of immune response under these conditions.

[Features of mucosal lesions of stomach and duodenum in children with chronic gastroduodenitis with different microflora content].

OBJECTIVE: Our aim was to reveale the features of histological mucosa with different composition of the microflora of stomach and duodenum in children with chronic gastroduodenitis. METHODS: The study included 122 children with chronic gastroduodenitis from 5 to 17 years old. All patients underwent endoscopy with histology of biopsy specimens of gastric and duodenal mucosa in 94 patients and in 48 patients among them with morphometry of biological material. Identification of herpes simplex virus 1, 2 types, cytomegalovirus, human papilloma virus 16, 18 types, Helicobacterpylori was carried out using polymerase chain reaction in biopsies of gastroduodenal mucosa and gastric juice. RESULTS: Children with chronic gastroduodenitis depending on the identified microorganisms were divided into groups: 1st (n = 51)--without detectable microorganisms, 2nd (n = 28)--with associations of H. pylori and viruses, 3rd (n = 15)--only with viruses, 4th (n = 28)--with H. pylori. Thus, in patients with H. pylori inflammation was noted mainly in the antral mucosa and dystrophic changes--in the duodenal mucosa. In the presence of viruses the inflammation was expressed more in the fundal stomach and duodenum. When viral-bacterial associations were observed most pronounced inflammatory-dystrophic process was localized throughout the gastroduodenal mucosa. CONCLUSION: In children with chronic gastroduodenitis in the presence of bacterial, viral and mixed microflora in the stomach and duodenum identified characteristic histological features of the mucosa, manifested in a different localization and severity of inflammatory and dystrophic changes.

[Endogenous intoxication and biochemical protection in children with celiac disease: state assesment and correlation-regression analysis].

AIM: The purpose of the study was to determine the characteristics of endogenous intoxication parameters, biochemical protection and reveal their interaction in children with celiac disease. MATERIALS AND METHODS: 81 children aged from 1 to 16 years with celiac disease were examined in acute and remission periods. In erythrocytes, blood serum and urine we determined low and moderate molecular weight substances (LMMWS), oligopeptides OP); in erythrocytes--the value of erythrocyte mechanical hemolysis (MH), malondialdehyde (MDA) content, the activity of glutathione reductase GR) and superoxide dismutase (SOD); in blood serum--ceruloplasmin (CP) level, alcohol dehydrogenase (ADH) activity; in erythrocytes and blood serum--glutathione transferase (GT), and calculated intoxication index (II). RESULTS: In children with celiac disease in acute and remission periods LMMWS, OP, II levels in blood were statistically significantly high, while LMMWS level in urine was low. In both periods MH activity was high (p < 0.001), and GSR (p < 0.001) and SOD (p < 0.01) levels were low. We revealed the correlation between MDA and II (r = 0.67; p = 0.006), erythrocyte LMMWS and SOD (r = -0.61; p = 0.015), erythrocyte LMMWS and ADH (r = 0.62; p = 0.006), between GT and OP in urine (r = -0.31; p = 0.026), GTand MDA (r = 0.68; p = 0.000), GT and MH (r = -0.46; p = 0.004), between MDA and CP (r = 0.57; p = 0.002) that made it possible to develop the models of dependence of the parameters in relation to each other. CONCLUSION: In celiac disease there is endogenous intoxication. The changes of the first and the second phases of biotransformation, antioxidant protection is an essential factor of the disease pathogenesis, since they have an effect on endogenous intoxication formation that should be taken into consideration in therapy.

[Forward-morphological criteria of ulcerative colitis relapse and continuous flow in children].

UNLABELLED: Inflammatory bowel disease is one of the most difficult groups of pathologies in pediatric gastroenterology, due to the steady growth of their prevalence, offset debut at an earlier age, the increase in the incidence of severe complicated forms. Established clinical, genetic, serologic criteria for progression of ulcerative colitis are contradictory, and some--the reach of most medical institutions. PURPOSE: to evaluate the prognostic significance of morphological features of ulcerative colitis relapse and continuous flow. MATERIALS AND METHODS: a retrospective study conducted histological kolonobioptatov 26 children with recurrent, 20--with a continuous flow of ulcerative colitis during their primary treatment in a hospital, the comparison group consisted of 50 children without inflammatory bowel disease. RESULTS: morphological characteristics identified predictors of recurrent ulcerative colitis in the form of severe eosinophilic infiltration of the epithelium, lamina propria of the mucosa. For a continuous flow was characterized: high density cell infiltration of the lamina propria mucosa epithelium predominantly under represented plasma cells, fibroblasts, sclerosis of the basal membrane, the presence of epithelial arcades deformed crypt abscesses. CONCLUSION: the extended study of biopsy material, including assessment of the composition and location of infiltration, fibroblast pool of epithelial-connective relationships in the colonic mucosa of children with ulcerative colitis will not only assess the inflammatory process, but also to predict the course of disease, thereby defining a long-term tactics treatment.

[Changes of epidermal growth factor level in blood serum, saliva and gastric juice in children with duodenal ulcer].

AIM: The aim of our study is to investigate EGF content in biological mediums in children with duodenum ulcer depending on phase of the disease and different variants of its course. MATERIALS AND METHODS: The present study was performed in Federal State Establishment "Nizhniy Novgorod Research Institute of Children Gastroenterology", Nizhniy Novgorod, Russia. 92 children, between the ages of 8 to 17, with duodenum ulcer were under observation. Endoscopy was performed by Pentax endoscope (FG-24V). EGF detection was performed in blood serum, gastric juice and saliva by ELISA method with Human EGF Kit, "Invitrogen", USA. RESULTS: The peculiarities of EGF level changes in human biological mediums, depending on phase of the disease. The highest EGF level was detected with acute peptic ulcer in the presence of ulcerous defects. EGF level increasing was marked out in the remission phaseas ulcerous defects healing, and it didn't reach normal values in gastric juice. EGF content changes in biological mediums were revealed with different variants of duodenum ulcer clinical course in children. The lowest EGF level was marked out in blood, saliva and gastric juice with unfavorable course of the disease (frequent relapses, cicatricial-ulcerous strains formation), which can serve as a prognostic factor.

[Effect of antipsychotic amisulpride on immune reactivity].

The effect of atypical antipsychotic solian (amisulpride), binding predominantly to dopamine D2/D3-receptors, on the immune reactivity has been studied in mice of the CBA strain with different psychoemotional states (aggressive and submissive behavior). In addition, the effect of solian on the expression of various CD-markers of lymphocytes in has been analyzed in vitro for patients with schizophrenia diagnosis. Chronic (10 days) administration of solian in mice at a dose of 5.0 mg/kg resulted in a significant suppression of the immune response to T-dependent antigen (sheep red blood cells). This effect was manifested in animals with both psychoemotional states, but was more expressed in aggressive animals. In the in vitro system, solian produced opposite effects on the expression of surface CD receptors in lymphocytes of patients with schizophrenia. It is suggested that solian does not only affects immune function through D2 receptors of the brain, but also directly influences immunocompetent cells.

Pterin metabolism, inflammation and oxidative stress biochemical markers in schizophrenia: Factor analysis and assessment of clinical symptoms associations.

Various aspects of folate and tetrahydrobiopterin (BH4) metabolism disturbances have been detected in patients with schizophrenia.Data were obtained that disturbances in the pterins (folates and BH4) metabolism can be associated with oxidative stress and inflammation, but has not yet been confirmed in clinical studies in schizophrenia. Within the framework of this study, a correlation and factor analysis of biochemical markersof pterin metabolism, inflammation and redox imbalance in patients with schizophrenia was performed in order to test the hypothesis of the single etiopathogenetic node, including the studied biochemical processes. Methods: 125 patients with schizophrenia and 95 healthy volunteers were randomly selected and evaluated with a biochemical examination of BH4, folate, B12, homocysteine, C-reactive protein, interleukin-6, reduced glutathione levels in the blood serum; activity of superoxide dismutase and catalase - in erythrocytes; malondialdehyde - in blood plasma. All patients underwent an examination using standardized psychopathology rating scales. Spearman rank coefficient (ρ) with Benjamini-Hochberg correction was used for the correlation analysis. The principal components analysis (PCA) was used as a factor analysis. Results: Significant correlations were found within groups of pterin metabolism, inflammatory markers and redox-imbalance, and also between separate inflammation, oxidative stress and markers of pterin metabolism. The performed factor analysis made it possible to distinguish two components: 1 - pterin metabolism, 2 - oxidativeinflammatory markers. Despite the weak statistical associations and, possibly, functional relationships between pterin metabolism and oxidative/inflammation markers, each of the components has its own clinical correlates and, probably, a separate contribution to the pathology of schizophrenia.

[Adaptation of african swine fever virus (Asfarviridae: Asfivirus)to growth in the continuous culture PPK-66b cells by the method of accelerated passaging].

INTRODUCTION: African swine fever virus (ASF) is a large, enveloped virus with an icosahedral capsid morphology and a double-stranded DNA genome ranging in size from 170 to 190 kb. The replication cycle proceeds in two phases, the early phase lasting 4-6 hours and the late 8-20 hours after infection. The adaptation of the ASF virus to growth in continuous cell lines makes efficient and reliable genetic analysis and more accurate interpretation of its results. OBJECTIVE: Adaptation of a new isolate of the ASF virus to growth in a continuous cell line by the method of accelerated passages and preliminary genetic analysis of the resulting strain. MATERIALS AND METHODS: For virus isolation and passaging of the ASF virus, a porcine leukocyte cell culture (PL) and continuous cell cultures of porcine origin (ST, PK, PPK-66b) were used with Eagle MEM and HLA essential media with 10% porcine or fetal serum. RESULTS: The article presents data on the isolation and analysis of the changes in the reproductive properties of a new African swine fever (ASF) virus isolate in the process of adaptation to growth in a continuous piglet kidney cell culture clone b (PPK-66b). The current state of the problem of cultivation of the ASF virus, the features of its reproduction, and the basis of the genetic differentiation of its isolates are described in detail. Understanding the uniqueness of the nature of the ASF virus determined the approaches to the processes of its cultivation and adaptation. In this regard, the results of studies of cultural properties, and analysis of the nucleotide sequence of 6 genes of the new isolate, as well as phylogenetic analysis of these genes with already known strains and isolates of the ASF virus are presented. CONCLUSION: A new strain obtained in the process of cell adaptation of ASVF/Znaury/PPK-23 ASF virus by the accelerated passaging method reaches a high level of reproduction in 72 hours with an accumulation titer of 7.07 lg HAdE50/cm3. Primary genetic analysis allowed to establish the main phylogenetic relationships of the newly isolated strain with previously known variants of the current ASF panzootic.

[Clinical and experimental research of immunomodulatory effect of amisulpride].

Study of immunomodulatory effect of atypical antipsychotic amisulpride has revealed a positive clinical effect after 6-week therapy of schizophrenic patients regarding both positive and negative symptoms. A decrease in activity of humoral immunity factors (B lymphocytes, immunoglobulins, HLADR(+)-cells) identified among schizophrenic patients in the process of amisulpride therapy can be attributed to a positive effect optimizing the ratio Th1/Th2. Amisulpride when used under experimental conditions produced a suppression of IgM-immune response in mice of the C57BL/6J strain. This effect was more expressed in animals with aggressive behavior pattern.

[Effect of activation of serotonin 5-HT1A-receptors on the immune response in mice of the ASC strain with depressive-like behavior].

Selective activation of serotonin 5-HT(1A)-receptors produced different effects on immunological reactivity in mice of ASC strain with genetic predisposition to depressive-like behavior, and parental CBA and AKR strains displaying no depressive reactions. Administration of 5-HT(1A)-receptors agonist 8-OH-DPAT at low dose (0.1 mg/kg) affecting upon presynaptic receptors resulted in immunostimulation in CBA mice and did not change the immune response level in mice of ASC strain. Activation of postsynaptic 5-HT(1A)-receptors with higher dose of 8-OH-DPAT (1.0 mg/kg) caused immunosuppression in CBA and AKR strains while under the same conditions the immune response of ASC mice was increased. Decrease the immune reactions in ASC mice was observed only after application of 8-OHDPAT at dose of 5 mg/kg. The changes of functional activity of pre- and postsynaptic 5-HT(1A)-receptors under a high predisposition to depressive-like behavior providing different effects of this receptor activation on immune function are discussed.

[Liver detoxifying function disorders in children with chronic hepatic disease and their correction].

In the present study liver detoxifying function state in children with chronic hepatitis and pigmentary hepatosis was examined. An endogenous intoxication level increase, peroxide processes and biotransformation system activation were established against the background of endotoxicosis substrate accumulation in blood. The dynamics of clinical symptoms and liver detoxifying function indicators was estimated against the background of the complex treatment with Reamberin. In our study we have noticed detoxication mechanisms improvement, and that fact has been confirmed by a decrease of endogenous intoxication level and significant middle-mass molecules decreasing in blood plasma as well as intoxication index and glutathione enzymes activity in blood.