First Measurement of Hard Exclusive π

The polarized cross-section ratio σ_{LT^{'}}/σ_{0} from hard exclusive π^{-}Δ^{++} electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2 GeV/10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5 GeV^{2} up to 7 GeV^{2}. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ^{++} transition generalized parton distributions. A comparison to existing results for hard exclusive π^{+}n and π^{0}p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.

First CLAS12 Measurement of Deeply Virtual Compton Scattering Beam-Spin Asymmetries in the Extended Valence Region.

Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. The results greatly extend the Q^{2} and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.

First Measurement of Λ Electroproduction off Nuclei in the Current and Target Fragmentation Regions.

We report results of Λ hyperon production in semi-inclusive deep-inelastic scattering off deuterium, carbon, iron, and lead targets obtained with the CLAS detector and the Continuous Electron Beam Accelerator Facility 5.014 GeV electron beam. These results represent the first measurements of the Λ multiplicity ratio and transverse momentum broadening as a function of the energy fraction (z) in the current and target fragmentation regions. The multiplicity ratio exhibits a strong suppression at high z and an enhancement at low z. The measured transverse momentum broadening is an order of magnitude greater than that seen for light mesons. This indicates that the propagating entity interacts very strongly with the nuclear medium, which suggests that propagation of diquark configurations in the nuclear medium takes place at least part of the time, even at high z. The trends of these results are qualitatively described by the Giessen Boltzmann-Uehling-Uhlenbeck transport model, particularly for the multiplicity ratios. These observations will potentially open a new era of studies of the structure of the nucleon as well as of strange baryons.

Observation of Correlations between Spin and Transverse Momenta in Back-to-Back Dihadron Production at CLAS12.

We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction in the deep inelastic scattering process. In this reaction, two hadrons are produced in opposite hemispheres along the z axis in the virtual photon-target nucleon center-of-mass frame, with the first hadron produced in the current-fragmentation region and the second in the target-fragmentation region. The data were taken with longitudinally polarized electron beams of 10.2 and 10.6 GeV incident on an unpolarized liquid-hydrogen target using the CLAS12 spectrometer at Jefferson Lab. Observed nonzero sinΔϕ modulations in ep→e^{'}pπ^{+}X events, where Δϕ is the difference of the azimuthal angles of the proton and pion in the virtual photon and target nucleon center-of-mass frame, indicate that correlations between the spin and transverse momenta of hadrons produced in the target- and current-fragmentation regions may be significant. The measured beam-spin asymmetries provide a first access in dihadron production to a previously unexplored leading-twist spin- and transverse-momentum-dependent fracture function. The fracture functions describe the hadronization of the target remnant after the hard scattering of a virtual photon off a quark in the target particle and provide a new avenue for studying nucleonic structure and hadronization.

Observation of Azimuth-Dependent Suppression of Hadron Pairs in Electron Scattering off Nuclei.

We present the first measurement of dihadron angular correlations in electron-nucleus scattering. The data were taken with the CLAS detector and a 5.0 GeV electron beam incident on deuterium, carbon, iron, and lead targets. Relative to deuterium, the nuclear yields of charged-pion pairs show a strong suppression for azimuthally opposite pairs, no suppression for azimuthally nearby pairs, and an enhancement of pairs with large invariant mass. These effects grow with increased nuclear size. The data are qualitatively described by the gibuu model, which suggests that hadrons form near the nuclear surface and undergo multiple scattering in nuclei.These results show that angular correlation studies can open a new way to elucidate how hadrons form and interact inside nuclei.

Analysis of the level of optopedical rehabilitation in studying the microbiome and evaluation of the degree of fixation of removable plated prosthesis.

The widespread use of traditional removable prosthetics is explained by the relative simplicity of the technological stages of manufacture and determines its availability. The development of prosthetic stomatitis of the oral cavity is facilitated by poor fixation and stabilization of removable orthopedic structures. Microbiome biofilms formed on the surface of dental orthopedic structures can help reduce their service life and cause an inflammatory process of the oral cavity of microbial etiology during dental prosthetics in the process of orthopedic rehabilitation. The purpose of the study: to assess the level of adaptation of patients during orthopedic rehabilitation based on the study of the microbiome and the assessment of the degree of fixation of removable lamellar dentures. Qualitative and quantitative characteristics of the microbiome of prostheses at the stages of orthopedic pealitation were assessed; facultative anaerobic species belonging to the genera Staphylococcus, Micrococcus, Enterococcus, Streptococcus, Klebsiella prevailed;noted the elimination of microorganisms of the genera Bifidobacterium and Lactobacterium, yeast-like fungi of the species Candida albicans were isolated. An analysis of the index of fixation of prostheses showed an increase depending on the duration of use; a good level of fixation of prostheses was established in groups of patients.

Analysis of micro-relief of biofilm of yeast Candida albicans of basic plastics by the method of laser modulation interference microscopy.

The development of mycotic colonization of the base surface with further biodegradation of acrylic plastics is currently of undoubted interest. The oral cavity is a favorable ecological niche for colonization by fungi and their subsequent possible invasion into the epithelium of the oral mucosa. The method of modulation interference laser microscopy is of considerable interest to researchers in medicine in the context of obtaining the necessary information about the morphological characteristics of microbial cells and the microbiome community as a whole during the colonization of a certain ecological niche in the human body. Purpose of the study: to analyze the microrelief of the biofilm of yeast-like fungi of the species Candida albicans of base plastics of the hot type of polymerization using the method of laser modulation interference microscopy. An experimental study was carried out in order to study biofilms of yeast-like fungi of the genus Candida on samples of basic plastics, an image of a biofilm of yeast-like fungi of the species Candida albicans was obtained on the surface of a plastic of a hot type of polymerization (polymethyl methacrylate) in the visualization of the phase portrait, a description of its horizontal and vertical bioprofile. As a result of the research, the heterogeneous structure of the biofilm was determined, due to the different density and accumulation of cells along the surface, the characteristics of the surface were established in accordance with the roughness criteria. The microrelief parameters on a separately arbitrarily selected section line allow one to determine the characteristics of the biofilm in the required area and make it possible to judge the nature of its formation in a certain biological niche.

Improved Λp Elastic Scattering Cross Sections between 0.9 and 2.0 GeV/c as a Main Ingredient of the Neutron Star Equation of State.

Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this is true, then hyperon-nucleon interactions will play a significant part in the neutron star equation of state. Yet, compared to other elastic scattering processes, there is very little data on Λ-N scattering. This experiment utilized the CEBAF Large Acceptance Spectrometer (CLAS) detector to study the Λp→Λp elastic scattering cross section in the incident Λ momentum range 0.9-2.0 GeV/c. These are the first data on this reaction since the 1970s. The new cross sections have significantly better accuracy and precision than the existing world data, and the techniques developed here can also be used in future experiments.

[Use of scanning electron microscopy to study Candida albicans biofilms on the surface of base plastics of removable orthopedic constructions.]

The most common pathology in the clinic of orthopedic dentistry is the presence of partial adentia in patients, manifested in the form of defects of dentition of various localization and length. Removable orthopedic structures in the oral cavity are a potential place for adhesion and colonization of microorganisms. The aim of the research was to study Candida albicans biofilms on the surface of base plastics of removable orthopedic structures using scanning electron microscopy. 175 cultures of C. albicans were isolated and identified from the oral mucosa of patients at various stages of orthopedic rehabilitation. When studying the surface of samples of plastics of hot and cold type polymerization and Candida biofilms using a JEOL JCM 5700 scanning electron microscope (JEOL, Japan), features of biofilm formation were established. An assessment of the nature of the manifestation of the hemagglutinating activity of clinical strains of Candida fungi in the hemagglutination test with human erythrocytes I (O), II (A) of the human and guinea pig blood groups was carried out. The total number of hemagglutinating strains was 37.14%, with the prevalence of the proportion of manna-resistant (MRHA) cultures - 23.43% of cases. Micrographs of the C. albicans yeast-like biofilm biofilm were obtained on the surface of hot and cold-type plastics in incubation dynamics. Scanning electron microscopy revealed the most pronounced changes in the surface of hot plastics of polymerization compared to cold plastics with long incubation of C. albicans, which characterize the loosening of plastics and the appearance of cracks on the surface, and the cracking of a yeast-like fungus biofilm was noted.

[THE MYCOBIOTA OF TUNICA MUCOSA OF MOUTH AND SURFACE OF REMOVABLE ACRYLIC LAMINAR DENTAL PROSTHESES UNDER ORTHOPEDIC REHABILITATION].

The analysis was carried out to detect mycobiota of tunica mucosa of mouth and surface of dental prostheses under orthopedic rehabilitation using removable acrylic laminar dental prostheses. The inoculation of biosamples received from examined patients permitted to isolate Candida albicans. The C. albicans from tunica mucosa of mouth of patients before prosthetics inoculated in low concentration making up 0.33±0.23 CFU/ml in comparison with concentration of 1.92±0.53 CFU/ml after prosthetics. The highest content of C. albicans was marked in biosample from surface of dental prostheses in comparison with biotope of tunica mucosa of mouth of patients. The concentration of microbiota from surface of dental prostheses signicantly surpassed the same on tunica mucosa of mouth of patients prior prosthetics. In patients with removable acrylic laminar dental prostheses under orthopedic rehabilitation various spectrum of representatives of microbiota was detected From biosamples from surface of dentalprostheses of patients the most frequently were inoculated such representatives of gram-positive microbiota as S. aureus, Micrococcus spp., S.haemolyticus, and of gram-negative microbiota Klebsiella pneumonae, Pseudomonas aeruginosa. The cultural analysis of biosamples from patients with removable acrylic laminar dental prostheses detected Candida albicans on tunica mucosa of mouth before and after prosthetics as well as on surfaces of prostheses. The highest concentration of C.albicans is established in case of colonization of removable acrylic laminar dental prostheses. The received data testifies possible involvement of fungi capable of expressed potential ofpathogenicity, in development and maintenance of inflammatory process of tunica mucosa of mouth under orthopedic rehabilitation using removable acrylic laminar dental prostheses.

[The microbiological aspects of orthodontic treatment of children with dental maxillary anomalies].

The issues of pre-nosologic diagnostic and effectiveness of treatment of diseases of oral cavity is an actual issue in dentistry. The long- duration orthodontic treatment of patients with dentoalveolar anomalies using non-removable devices is followed by such negative consequences as development demineralization of enamel and caries registered during treatment and after remove ofdevices. The level of quantitative content of oral streptococci was analyzed and dental status in children with dentoalveolar anomalies was evaluated during treatment with non-removable devices was evaluated. The caries and inflammation of periodontium of oral cavity were most often detected in children with high level of content of streptococci. In different periods of study the firm tendency of increasing of concentration of Streptococcus mutans and S. sanguis of dental plaque of oral cavity is established. The established index indicators of dental status of patients testify intensity of caries damage, level of poor hygiene of oral cavity, development of average degree of severity of inflammation process of periodontium. The obtained results substantiate involvement ofstreptococci, associates of microbiota of dental plaque of oral cavity in children, in process of development of caries. The characteristics of micro-ecology of dental plaque to evaluate cariesgenic situation that can be used as a basis for constructing diagnostic algorithm under monitoring of patients with dentoalveolar anomalies with purpose of forthcoming planning and implementation of effective orthodontic treatment.

[Quantitative and qualitative analysis of oral microbiota by orthopedic rehabilitation with full and partial removable dentures].

Microbiological analysis of biomaterial surface in dental prosthesis showed the most common colonizing gram-positive species to be S. aureus, Micrococcus spp., S. haemolyticus, E. faecalis, mainly massive colonization with S. aureus was seen. The highest concentration of C. albicans colonization was found in removable dentures and may have a destructive effect on prosthetic material.

[The Bayesian framework of detection of cariesgenic Streptoccocus in dental plaque in children with distal occlusion under orthodontic treatment].

The application of Bayes theorem in medical diagnostic includes such important step as derivation for every symptom and diagnosis data values of finite or a posteriori probability of presence of germ, for instance S. sanguis, in patients receiving orthodontic treatment. This value expresses importance of the given symptoms for detection of germ presence. In the implemented studies the Bayes theorem was applied to evaluate probability of presence of particular germ in particular concentration (degree of semination, CO) under concrete symptom group. The rates were used to calculate probability of presence of cariesgenic streptococcus S. mutans and S. sanguis in prospect patient. The rates were calculated for the group with fixed orthodontic apparatuses. The high degree of risk of development of caries in children under orthodontic treatment is conditioned by a whole complex of existing unfavorable factors present in oral cavity. Hence, a powerful negative potential to develop expressed cariesgenic situation in oral cavity is present. The analysis of medical data of patients with distal occlusion was applied using Bayes theorem from the point of view their diagnostic value. The study established 36 symptoms, factors, risk factors and background diseases common in case of distal occlusion in children. The probability to detect the mentioned characteristics and likelihood ratio under different degree of concentration of cariesgenic Streptococcus mutans and Streptococcus sanguis in dental plaque of children was considered. The establishment of character of likelihood ratio for different qualitative content of streptococcus in case of isolation from biotope of dental plaque permitted to determine the informative characteristics. The Bayesian model can be applied in clinics as a computer program to process incoming information about patients with distal occlusion under active orthodontic treatment. The developed diagnostic algorithm in a fast and simple mode of clinical detection of caries and determination of concentration of cariesgenic Streptococcus.

[Structural properties of mixed saliva in persons with different levels of tooth resistance to caries].

Structural properties of mixed saliva were studied in 30 persons 16-18 years of age divided into 3 groups (10 persons in each) according to different levels of tooth resistance to caries -- 1st with high level of resistance (DMFT=0), 2nd with medium level of resistance (DMFT=4.3+/-0.82), 3rd with low level of resistance (DMFT=6.6+/-0.92). The difference between DMFT figures in groups 2 and 3 was insignificant. In salivary filtrate (collected in the rest conditions and after 5 g sugar load) pH (by potentiometry) and optical density (by photoelectric colorimetry) were determined. 60 saliva samples were collected and 240 determinations were made. In was found that 5 g sugar intake led to structural changes of oral fluid in all groups with different levels of tooth resistance to caries. But in persons with 0 caries incidence the oral fluid micelle resistance and saliva mineralizing capacity were higher than in persons with medium and low resistance to caries. The received data may be used for revelation of oral mineral homeostasis mechanisms and forecasting pathology arising in cases of its disturbance and for planning preventive and curative measures with consideration of their corrections depending upon the level of the individual resistance to caries.

Effect of hypoxia on metabolism and contractile function of the heart in rats with type 2 diabetes mellitus and abdominal obesity.

Type 2 diabetes mellitus was modeled in newborn albino rat pups. Metabolism and contractile activity of isolated heart under conditions of hypoxia were studied on adult rats. Contractile activity of the myocardium in animals with type 2 diabetes mellitus and abdominal obesity decreased during hypoxia. It was manifested in a decrease in systolic and developed pressure and disturbances in diastolic relaxation of the myocardium. Damage to cell membranes and increased secretion of aspartate transaminase into the coronary circulation were observed under conditions of energy deficit and activation of the anaerobic pathway of energy production. These changes became more pronounced with increasing the period of hypoxic exposure.

Expression of the Hoxa-13 gene correlates to hepatitis B and C virus associated HCC.

To study the Hoxa-13 gene in the liver, we examined its expression by RT-PCR in various liver cell lines, rat livers under different conditions, and human primary hepatocellular carcinomas (HCCs). The gene was found to be expressed in cell lines originating from liver stem-like cells, but not in cell lines originating from hepatocytes and bile duct epithelia. Expression was induced in rat livers after treatment with d-galactosamine, which is known to induce oval cell proliferation, but not after a two-thirds partial hepatectomy (2/3 PH) where induction of oval cell proliferation is thought not to occur. Expression of the gene correlated with human HCC samples associated with Hepatitis B or C virus infection in this small series. These results suggest that the Hoxa-13 gene may provide a potentially useful tool for elucidation of mechanisms involved in lineage-specific differentiation and carcinogenesis of liver stem cells.

[Role of disorders of metabolism in rat myocardium and endotoxemia in the pathogenesis of post-resuscitation cardiodepression]. / Rol' narushenii metabolizma v miokarde krys i éndotoksemii v patogeneze postreanimatsionnoi kardiodepressii.

The model of 4-min clinical death due to acute blood loss was used to study cardiac contractility, myocardial metabolism and causes of endotoxemia in early postresuscitation period. The investigations were made on the whole body, isolated, isovolemically contracting heart and isolated papillary muscle. A marked reduction in functional myocardial reserves, maximal within the first 24 hours of postresuscitation, with dominant defects in relaxation was seen. Pathogenetic factors responsible for cardiodepression are the following: hypoxia, impairment of bioenergetics, hyperactivation of lipid peroxidation, acidosis, membrane destruction, endotoxemia.

[Clinico-pathogenetic variants of the piriform muscle syndrome]. / Kliniko-patogeneticheskie varianty sindroma grushevidnoi myshtsy.

The method of diagnosis of pathogenetic variations or musculus piriformis syndrome (MPS) by means of computer tomography is described. 24 patients with early signs of lumbar osteochondrosis and MPS were examined. Two variations of MPS with specific clinical and tomographic features were revealed, namely: an early spastic (functional) type and degenerative-dystrophic one. The peculiarities of muscles (diameter, location, density) and of adjacent pelvic structures were investigated in 15 healthy controls. Differentiated treatment of MPS permitted to control the pain and to promote other clinical signs regression faster than conventional therapy.