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1.
Phys Rev Lett ; 130(21): 212301, 2023 May 26.
Article in English | MEDLINE | ID: mdl-37295104

ABSTRACT

We report here the first observation of directed flow (v_{1}) of the hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in mid-central Au+Au collisions at sqrt[s_{NN}]=3 GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165×10^{6} events in 5%-40% centrality, about 8400 _{Λ}^{3}H and 5200 _{Λ}^{4}H candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v_{1} slopes of _{Λ}^{3}H and _{Λ}^{4}H follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in the 3 GeV Au+Au collisions.

2.
Phys Rev Lett ; 130(11): 112301, 2023 Mar 17.
Article in English | MEDLINE | ID: mdl-37001106

ABSTRACT

We report on measurements of sequential ϒ suppression in Au+Au collisions at sqrt[s_{NN}]=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0%-60% centrality class, the nuclear modification factors (R_{AA}), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for ϒ(1S) and ϒ(2S) are 0.40±0.03(stat)±0.03(sys)±0.09(norm) and 0.26±0.08(stat)±0.02(sys)±0.06(norm), respectively, while the upper limit of the ϒ(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the ϒ(3S) is significantly more suppressed than the ϒ(1S) at RHIC. The level of suppression for ϒ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited ϒ states.

3.
Phys Rev Lett ; 130(8): 082301, 2023 Feb 24.
Article in English | MEDLINE | ID: mdl-36898098

ABSTRACT

We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, from center-of-mass energy (sqrt[s_{NN}]) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, µ_{B}≤110 MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, µ_{B}∼750 MeV at sqrt[s_{NN}]=3 GeV is starkly different from those at vanishing µ_{B}∼24 MeV at sqrt[s_{NN}]=200 GeV and higher collision energies.

4.
Klin Lab Diagn ; 67(4): 204-206, 2022 Apr 17.
Article in English | MEDLINE | ID: mdl-35575392

ABSTRACT

Fabry disease is an X-linked hereditary lysosomal storage disorder caused by mutations in the GLA gene. Neonatal screening for Fabry disease in males is feasible by measurement of α-galactosidase A activity in DBS using either the mass spectrometric or fluorigenic substrate. The aim of the study: to assess the possibility of introducing the compared methods into the practice of neonatal screening. In the both assays performed a statistically significant difference of the enzyme activity between affected individuals and controls is reported. The slight modification of the fluorimetric method by centrifugation of a 96-well microplate before measurement could improve signal to noise ratio.


Subject(s)
Fabry Disease , Fabry Disease/diagnosis , Fabry Disease/genetics , Humans , Infant, Newborn , Male , Mass Spectrometry , Mutation , Neonatal Screening/methods , alpha-Galactosidase/genetics
6.
Bull Exp Biol Med ; 162(1): 71-74, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27882465

ABSTRACT

Colonization of fluorinated surfaces produced by ion-plasma technology by Staphylococcus aureus was studied by scanning electron microscopy and surface energy analysis. It was shown that the intensity of colonization was determined by the surface relief and fluorine content. Formation of nanostructured surfaces accompanied by a sharp decrease in the surface energy prevented adhesion of Staphylococcus aureus cells to the fluorine-containing surface.


Subject(s)
Biofilms/drug effects , Fluorocarbons/chemistry , Plasma Gases/chemistry , Polytetrafluoroethylene/pharmacology , Staphylococcus aureus/drug effects , Bacterial Adhesion/drug effects , Biofilms/growth & development , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Microscopy, Electron, Scanning , Nanostructures/microbiology , Nanostructures/ultrastructure , Polytetrafluoroethylene/chemistry , Staphylococcus aureus/growth & development , Surface Properties , Thermodynamics , Titanium/chemistry , Titanium/pharmacology
7.
Mol Gen Mikrobiol Virusol ; 34(1): 18-25, 2016.
Article in Russian | MEDLINE | ID: mdl-27183717

ABSTRACT

The urgency of the staphylococcus research is due to its ability to cause severe infections: softtissue infections, endocarditis, sepsis, toxic shock syndrome, and food poisoning. Coagulase-positive Staphylococcus aureus is the main infection agent of intrahospital infections. This agent has many factors of pathogenicity, which are well known. Among the coagulase-negative staphylococcus (CNS) strains, S. haemolyticus and S. epidermidis are clinically important, because they cause infections in patients with weak immune system. The mechanisms of the CNS pathogenicity are insufficiently understood. The goal of this work was to evaluate the potential pathogenicity of clinical strains of CNS from their capacity to create biofilms and the character of their interaction with human body cells by the example of the HT-29 cell culture. The research was carried out in laboratory strain S. aureus ATCC 29213 and clinical strains S. haemolyticus SH39, S. epidermidis SE36-1 isolated from the neonatal autopsy materials. The visual tests of biofilm formation by each strain and testing of the impact of the strains on the cell culture HT-29 was carried out in this work. The two species of CNS form biofilms at a higher rate than S. aureus. Upon incubation for 2 h of HT-29 cells with staphylococcus strains tested in this work, adhesion of bacteria on cell surface was observed. The adhesion was most pronounced in case of S. aureus ATCC 29213 and S. haemolyticus SH39. Upon 3 h of incubation with S. aureus ATCC 29213 and S. haemolyticus SH39, destruction of cell HT-29 monolayer was observed. The incubation for 24 h with the 3 strains tested in this work caused complete destruction of cell HT-29 monolayer. The maximal toxic effect on HT-29 cells was inherent in the strain S. haemolyticus SH39. The aggregate of the results obtained in this work indicates the presence of the pathogenicity factors in the strains S. haemolyticus SH39, which require additional research.


Subject(s)
Biofilms/growth & development , Staphylococcus/physiology , Cell Line, Tumor , Humans
8.
Phys Rev Lett ; 116(11): 112302, 2016 Mar 18.
Article in English | MEDLINE | ID: mdl-27035295

ABSTRACT

We present results from a harmonic decomposition of two-particle azimuthal correlations measured with the STAR detector in Au+Au collisions for energies ranging from sqrt[s_{NN}]=7.7 to 200 GeV. The third harmonic v_{3}^{2}{2}=⟨cos3(ϕ_{1}-ϕ_{2})⟩, where ϕ_{1}-ϕ_{2} is the angular difference in azimuth, is studied as a function of the pseudorapidity difference between particle pairs Δη=η_{1}-η_{2}. Nonzero v_{3}^{2}{2} is directly related to the previously observed large-Δη narrow-Δϕ ridge correlations and has been shown in models to be sensitive to the existence of a low viscosity quark gluon plasma phase. For sufficiently central collisions, v_{3}^{2}{2} persist down to an energy of 7.7 GeV, suggesting that quark gluon plasma may be created even in these low energy collisions. In peripheral collisions at these low energies, however, v_{3}^{2}{2} is consistent with zero. When scaled by the pseudorapidity density of charged-particle multiplicity per participating nucleon pair, v_{3}^{2}{2} for central collisions shows a minimum near sqrt[s_{NN}]=20 GeV.

9.
Phys Rev Lett ; 116(13): 132301, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-27081970

ABSTRACT

We present the measurement of the transverse single-spin asymmetry of weak boson production in transversely polarized proton-proton collisions at sqrt[s]=500 GeV by the STAR experiment at RHIC. The measured observable is sensitive to the Sivers function, one of the transverse-momentum-dependent parton distribution functions, which is predicted to have the opposite sign in proton-proton collisions from that observed in deep inelastic lepton-proton scattering. These data provide the first experimental investigation of the nonuniversality of the Sivers function, fundamental to our understanding of QCD.

10.
Phys Rev Lett ; 116(6): 062301, 2016 Feb 12.
Article in English | MEDLINE | ID: mdl-26918982

ABSTRACT

We present high precision measurements of elliptic flow near midrapidity (|y|<1.0) for multistrange hadrons and ϕ meson as a function of centrality and transverse momentum in Au+Au collisions at center of mass energy √[sNN]=200 GeV. We observe that the transverse momentum dependence of ϕ and Ω v2 is similar to that of π and p, respectively, which may indicate that the heavier strange quark flows as strongly as the lighter up and down quarks. This observation constitutes a clear piece of evidence for the development of partonic collectivity in heavy-ion collisions at the top RHIC energy. Number of constituent quark scaling is found to hold within statistical uncertainty for both 0%-30% and 30%-80% collision centrality. There is an indication of the breakdown of previously observed mass ordering between ϕ and proton v2 at low transverse momentum in the 0%-30% centrality range, possibly indicating late hadronic interactions affecting the proton v2.

11.
Vestn Oftalmol ; 132(6): 70-77, 2016.
Article in Russian | MEDLINE | ID: mdl-28121302

ABSTRACT

To date, the internal limiting membrane (ILM), specifically, the side facing the retina, has never been studied by two parallel, mutually complementary methods. This is an attempt to explain favorable results of ILM peeling in various macular pathologies. AIM: By employing scanning (SEM) and transmission electron microscopy (TEM), to identify morphological features of epiretinal samples removed during vitrectomy in patients with lamellar macular hole (LMH) or epiretinal membrane (ERM). MATERIAL AND METHODS: We studied 23 eyes of 23 patients divided into two groups. The first group (13 samples, 11 eyes) consisted of patients with LMH; the second (12 samples, 12 eyes) - with ERM. The surgeries yielded a total of 21 epiretinal samples peeled simultaneously with the ILM and 4 epiretinal samples (2 eyes) peeled in two parts, the second part containing the ILM. One half of the samples was studied by SEM without prior dehydratation, the other - by TEM. RESULTS: The study revealed a high degree of ultrastructural similarity between the two groups of ILM samples. Judging from SEM findings, two sides of the membrane were clearly identified. Porous coral-like structures (PCS) were discovered on the side facing the retina. TEM in the area of PCS discovered parallel arrangement of multiple Muller cell (MC) bodies and processes separated by wide layers of the intercellular matrix. The vitreal side of all ILM samples was notable for numerous fibroblast-like cells. Many variously shaped petrified structures were found on both sides of the membrane. CONCLUSION: During the so called ILM peeling, the surgeon removes a layered structure that includes the basal membrane of MC, cells and fibers attached to its vitreal side, and one more layer comprised by PCS and rather readily torn off from the main massif. The functional significance of this previously unknown structure as well as the effect of its partial removal during surgical manipulations with neurosensory retina in the macular region is yet to be investigated.


Subject(s)
Microscopy, Electron, Scanning/methods , Microscopy, Electron, Transmission/methods , Retina , Retinal Perforations/pathology , Aged , Female , Humans , Male , Middle Aged , Reproducibility of Results , Retina/diagnostic imaging , Retina/pathology , Retina/ultrastructure , Retinal Perforations/diagnosis , Retinal Perforations/surgery , Vitrectomy/methods , Vitreoretinal Surgery/methods
12.
Phys Rev Lett ; 115(22): 222301, 2015 Nov 27.
Article in English | MEDLINE | ID: mdl-26650297

ABSTRACT

Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v_{2}{2} and v_{2}{4}, for charged hadrons from U+U collisions at sqrt[s_{NN}]=193 GeV and Au+Au collisions at sqrt[s_{NN}]=200 GeV. Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v_{2}{2} on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. We also show that v_{2} vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.

13.
Phys Rev Lett ; 115(24): 242501, 2015 Dec 11.
Article in English | MEDLINE | ID: mdl-26705627

ABSTRACT

We report the observation of transverse polarization-dependent azimuthal correlations in charged pion pair production with the STAR experiment in p^{↑}+p collisions at RHIC. These correlations directly probe quark transversity distributions. We measure signals in excess of 5 standard deviations at high transverse momenta, at high pseudorapidities η>0.5, and for pair masses around the mass of the ρ meson. This is the first direct transversity measurement in p+p collisions.

14.
Vopr Virusol ; 60(4): 9-13, 2015.
Article in Russian | MEDLINE | ID: mdl-26665428

ABSTRACT

An experimental model of the primary genital herpes (herpes simplex type 2, HSV-2) in the female guinea pigs was suggested to study the infectious process activity of polyprenyl phosphates (PPP) and PPP+acyclovir (AC) complex treatment. The morphofunctional features of the guinea pig ovaries were studied in the control and experimental groups (the latter were inoculated with PPP and/or AC as a primary infection treatment) at the stage of the recurrent genital herpes aggravation. It was shown that in the case of combined PPP +AC use significant changes in the disease symptoms were observed, as well as a decrease in the infectious process activity and duration, and positive remote effect on the ovarian morphophysiology.


Subject(s)
Acyclovir/pharmacology , Antiviral Agents/pharmacology , Herpes Genitalis/drug therapy , Herpesvirus 2, Human/metabolism , Polyisoprenyl Phosphates/pharmacology , Animals , Disease Models, Animal , Female , Guinea Pigs , Herpes Genitalis/metabolism , Humans
15.
Mol Gen Mikrobiol Virusol ; 33(2): 20-5, 2015.
Article in Russian | MEDLINE | ID: mdl-26182663

ABSTRACT

The clinical material obtained surgically in patients with kidney stone disease (KSD) was tested for content of the stone microflora using PCR and standard microbiological methods. It was demonstrated that about 50% of stones in patients with KSD were infected with various infection agents as observed using standard microbiological and molecular genetic methods. The percentage of detection of the Mycoplasma hominis using cultural method is lower than the percentage detected using PCR, which is due to difficult isolation and cultivation, as well as DNA fragments of mycoplasma observed after antibiotic therapy. Studies based on modern microscopy methods showed that microorganisms on the surface of the kidney stone formed multispecies biofilms.


Subject(s)
Kidney Calculi/microbiology , Anti-Bacterial Agents/therapeutic use , Bacteriological Techniques , Biofilms/drug effects , Humans , Kidney Calculi/surgery , Microbial Consortia/physiology , Microscopy, Electron , Mycoplasma hominis/genetics , Mycoplasma hominis/isolation & purification , Mycoplasma hominis/physiology , Polymerase Chain Reaction , Ureaplasma/genetics , Ureaplasma/isolation & purification , Ureaplasma/physiology
16.
Phys Rev Lett ; 114(25): 252302, 2015 Jun 26.
Article in English | MEDLINE | ID: mdl-26197122

ABSTRACT

We present measurements of π(-) and π(+) elliptic flow, v(2), at midrapidity in Au+Au collisions at √[s(NN)]=200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV, as a function of event-by-event charge asymmetry, A(ch), based on data from the STAR experiment at RHIC. We find that π(-) (π(+)) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at √[s(NN)]=27 GeV and higher. At √[s(NN)]=200 GeV, the slope of the difference of v(2) between π(-) and π(+) as a function of A(ch) exhibits a centrality dependence, which is qualitatively similar to calculations that incorporate a chiral magnetic wave effect. Similar centrality dependence is also observed at lower energies.

17.
Klin Lab Diagn ; 60(12): 59-64, 2015 Dec.
Article in Russian | MEDLINE | ID: mdl-27032256

ABSTRACT

The study was carried out to analyze morphology of biofilm of periodontium and to develop electronic microscopic criteria of differentiated diagnostic of inflammatory diseases of gums. The scanning electronic microscopy was applied to analyze samples of bioflm of periodont from 70 patients. Including ten patients with every nosologic form of groups with chronic catarrhal periodontitis. of light, mean and severe degree, chronic catarrhal gingivitis, Candida-associated paroperiodontitis and 20 healthy persons with intact periodontium. The analysis was implemented using dual-beam scanning electronic microscope Quanta 200 3D (FEI company, USA) and walk-through electronic micJEM 100B (JEOL, Japan). To detect marker DNA of periodont pathogenic bacteria in analyzed samples the kit of reagentsfor polymerase chain reaction "MultiDent-5" ("GenLab", Russia). The scanning electronic microscopy in combination with transmission electronic microscopy and polymerase chain reaction permits analyzing structure, composition and degree of development of biofilm of periodontium and to apply differentiated diagnostic of different nosologic forms of inflammatory diseases of periodontium, including light form of chronic periodontitis and gingivitis. The electronic microscopical indications of diseases ofperiodontium of inflammatory character are established: catarrhal gingivitis, (coccal morphological alternate), chronic periodontitis (bacillary morphological alternate), Candida-associated periodontitis (Candida morphological alternate of biofilm ofperiodontium).


Subject(s)
Aggregatibacter actinomycetemcomitans/ultrastructure , Biofilms/growth & development , Candida albicans/ultrastructure , Gingivitis/diagnosis , Periodontitis/diagnosis , Porphyromonas gingivalis/ultrastructure , Prevotella intermedia/ultrastructure , Adolescent , Adult , Aggregatibacter actinomycetemcomitans/genetics , Aggregatibacter actinomycetemcomitans/isolation & purification , Biofilms/classification , Candida albicans/genetics , Candida albicans/isolation & purification , Case-Control Studies , Chronic Disease , Diagnosis, Differential , Female , Gingiva/microbiology , Gingiva/ultrastructure , Gingivitis/microbiology , Gingivitis/pathology , Humans , Male , Microscopy, Electron, Scanning , Middle Aged , Periodontitis/microbiology , Periodontitis/pathology , Polymerase Chain Reaction , Porphyromonas gingivalis/genetics , Porphyromonas gingivalis/isolation & purification , Prevotella intermedia/genetics , Prevotella intermedia/isolation & purification , Reagent Kits, Diagnostic , Severity of Illness Index
18.
Article in Russian | MEDLINE | ID: mdl-26829856

ABSTRACT

AIM: Study processes of microbial colonization and persistence of microorganisms in polymer materials for medical use. MATERIALS AND METHODS: Samples (1 x 1 cm plates) of polymer plastics for production of removable dental prosthesis based on polyurethane and acryl were used, that were incubated with clinical isolates of Pseudomonas aeuruginosa, Staphylococcus aureus in Luria-Bertani broth nutrient media for 24, 48 hours and 7, 14 days and for 1, 5 and 3 months at a temperature of 37 degrees C. Dynamics of interaction process of microorganisms with polymer materials were studied using scanning electron microscope Quanta 200 3D (FEI Company, USA). The samples were fixated after incubation with 10% of neutral formaldehyde, dehydration with alcohols or acetone, typical for SEM, was not carried out, that allowed to conserve the native structure of the samples, including exo-cell matrix of biofilms. RESULTS: Electron-microscopical data on stages of interaction of bacteria with the surface of medical plastics were obtained. Biofilms were shown to be formed on abiotic surfaces and biodestructive changes of plastics appeared. A question on the possibility of prolonged persistence of pathogenic for human microorganisms in artificial prosthesis is discussed. CONCLUSION: The developed experimental model of formation of biofilm on abiotic surfaces could be the basis for carrying out studies directed on the fight with biofilms, by using SEM.


Subject(s)
Dental Prosthesis/adverse effects , Plastics/adverse effects , Pseudomonas aeruginosa/growth & development , Staphylococcus aureus/drug effects , Biofilms/drug effects , Biofilms/growth & development , Culture Media , Dental Prosthesis/microbiology , Humans , Plastics/therapeutic use , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/growth & development , Surface Properties/drug effects , Temperature
19.
Ukr Biochem J ; 86(3): 33-40, 2014.
Article in English | MEDLINE | ID: mdl-25033552

ABSTRACT

Ribonucleases (RNases) are present in base-level amounts in intact plants, but this level is able to increase greatly under stress conditions. The possible cause for such an increase is protection against plant RNA-virus attack. Buckwheat burn virus (BBV) is a highly virulent pathogen that belongs to Rhabdoviridae family. In our study, we have analyzed the correlation between RNase activity and resistance of different buckwheat cultivars to BBV infection. Two cultivars, Kara-Dag and Roksolana, with different sensitivities to BBV have been used. Kara-Dag is a cultivar with medium sensitivity to virus and Roksolana is a tolerant cultivar. It has been shown that the base level of RNase activity in Roksolana cultivar was in most cases higher than the corresponding parameter in Kara-Dag cultivar. Both infected and uninfected plants of Roksolana cultivar demonstrated high RNase activity during two weeks. Whereas infected plants of Kara-Dag cultivar demonstrated unstable levels of RNase activity. Significant decline in RNase activity was detected on the 7th day post infection with subsequent gradual increase in RNase activity. Decline of the RNase activity during the first week could promote the virus replication and therefore more successful infection of upper leaves of plants. Unstable levels of RNase activity in infected buckwheat plants may be explained by insufficiency of virus-resistant mechanisms that determines the medium sensitivity of the cultivar to BBV. Thus, plants of buckwheat cultivar having less sensitivity to virus, displayed in general higher RNase activity.


Subject(s)
Fagopyrum/immunology , Plant Leaves/immunology , Plant Proteins/metabolism , Ribonucleases/metabolism , Fagopyrum/enzymology , Fagopyrum/virology , Host-Pathogen Interactions , Plant Diseases , Plant Immunity , Plant Leaves/enzymology , Plant Leaves/virology , Plant Proteins/immunology , Rhabdoviridae/pathogenicity , Rhabdoviridae/physiology , Ribonucleases/immunology
20.
Article in Russian | MEDLINE | ID: mdl-24107884

ABSTRACT

In this study authors searched for chromosomal aberrations in 71 children with developmental delay or idiopathic mental retardation using Human Genome CGH Microarray Kits 4×44K and 8×60K (Agilent Technologies, USA). Microdeletions and microduplications, as well as CNV, which may be related to intellectual disability and associated with regions of known hereditary diseases or chromosomal syndromes were identified in 14 (20%) children (these patients are described in this article). During the analysis, candidate genes localized within the regions of aberrations and associated with development and functioning of nervous system were denoted.


Subject(s)
Comparative Genomic Hybridization , Intellectual Disability/genetics , Adolescent , Child , Female , Gene Deletion , Gene Duplication , Humans , Intellectual Disability/diagnosis , Male
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