Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Publication year range
1.
Phys Rev Lett ; 130(8): 083801, 2023 Feb 24.
Article in English | MEDLINE | ID: mdl-36898103

ABSTRACT

We observe linear and nonlinear light localization at the edges and in the corners of truncated moiré arrays created by the superposition of periodic mutually twisted at Pythagorean angles square sublattices. Experimentally exciting corner linear modes in the femtosecond-laser written moiré arrays we find drastic differences in their localization properties in comparison with the bulk excitations. We also address the impact of nonlinearity on the corner and bulk modes and experimentally observe the crossover from linear quasilocalized states to the surface solitons emerging at the higher input powers. Our results constitute the first experimental demonstration of localization phenomena induced by truncation of periodic moiré structures in photonic systems.

2.
Phys Rev Lett ; 128(9): 093901, 2022 Mar 04.
Article in English | MEDLINE | ID: mdl-35302806

ABSTRACT

We report the experimental observation of nonlinear light localization and edge soliton formation at the edges of fs-laser written trimer waveguide arrays, where transition from nontopological to topological phases is controlled by the spacing between neighboring trimers. We found that, in the former regime, edge solitons occur only above a considerable power threshold, whereas in the latter one they bifurcate from linear states. Edge solitons are observed in a broad power range where their propagation constant falls into one of the topological gaps of the system, while partial delocalization is observed when considerable nonlinearity drives the propagation constant into an allowed band, causing coupling with bulk modes. Our results provide direct experimental evidence of the coexistence and selective excitation in the same or in different topological gaps of two types of topological edge solitons with different internal structures, which can rarely be observed even in nontopological systems. This also constitutes the first experimental evidence of formation of topological solitons in a nonlinear system with more than one topological gap.

3.
Klin Lab Diagn ; 65(2): 131-136, 2020.
Article in Russian | MEDLINE | ID: mdl-32159312

ABSTRACT

The lack of specific symptoms for the early detection of gastric cancer leads to the fact that it is often diagnosed at a late stage, when the prognosis is unfavorable. The analysis of molecular markers in addition to standard diagnostic procedures is a promising approach for improving the preoperative diagnosis of both gastric cancer and precancerous changes in the mucosa. Therefore, the aim of our study was to analyze the diagnostic significance of using miRNA expression to diagnosis gastric cancer and precancerous conditions (dysplasia) in histological material. In this work, 122 samples of archival histological material in the form of paraffin blocks were used: 34 samples of gastric adenocarcinoma, 54 samples of gastric ulcers with dysplasia and 34 samples of normal gastric mucosa obtained from patients after bariatric surgery. The expression level of miRNA-145-5p, -150-5p, -20a-5p, -21-5p, -31-5p, -34a-5p, -375 was determined using real-time RT-PCR. Samples were stratified into different groups using the C-RT decision tree algorithm. All miRNAs, except miRNA-20a, were included in the decision tree, which allows stratification of samples for normal mucosa, dysplasia, and gastric cancer. Normal mucosa can be distinguished from gastric cancer only by miRNA-34a, -21, -375. Diagnostic characteristics for the detection of dysplasia: specificity - 97%, sensitivity - 87%; for the detection of gastric cancer: specificity - 91%, sensitivity - 93%. The sufficiently high values of the diagnostic characteristics for detecting dysplasia of the gastric mucosa and gastric cancer obtained in our study indicate the possibility of using expression data of a small amount of miRNAs for the effective separation of samples with tumor and precancerous changes in the stomach tissue.


Subject(s)
MicroRNAs/genetics , Precancerous Conditions/diagnosis , Stomach Neoplasms/diagnosis , Biomarkers, Tumor/genetics , Gastric Mucosa/pathology , Gene Expression Regulation, Neoplastic , Humans , Paraffin Embedding , Precancerous Conditions/genetics , Sensitivity and Specificity , Stomach Neoplasms/genetics
4.
Kardiologiia ; 52(4): 20-4, 2012.
Article in Russian | MEDLINE | ID: mdl-22839512

ABSTRACT

One of the foundations of the modern treatment of myocardial infarction (MI) is a combination antiplatelet therapy consisting of acetylsalicylic acid (ASA) and clopidogrel. Pharmacodynamic and clinical studies have demonstrated that the polymorphism CYP2C19 (CYP2C19*2 allele) is associated with a reduced antiplatelet effect of clopidogrel and an increase in the incidence of severe cardiovascular complications. The study included 97 patients with MI. Coronary angiography was performed with subsequent standard treatment of MI, including stenting of the infarct-related coronary artery. CYP2C19 polymorphism was determined by polymerase chain reaction. At 6months, outcomes were determined. The frequency of allele CYP2C19*2 was 22.7%. We found statistically insignificant differences in the prevalence of CYP2C19 gene polymorphism in different forms of myocardial infarction. In contrast to the authors, who previously published data on the effect of CYP2C19 gene polymorphism on cardiovascular complications, we found no differences according to genotype. CYP2C19 gene polymorphism does not influence the prognosis for the next six months, if to patient follow medical recommendations, including the regular use of clopidogrel.


Subject(s)
Aryl Hydrocarbon Hydroxylases/genetics , Biotransformation/genetics , Myocardial Infarction/genetics , Ticlopidine/analogs & derivatives , Aged , Angioplasty, Balloon, Coronary , Aspirin/administration & dosage , Aspirin/pharmacokinetics , Clopidogrel , Coronary Angiography , Cytochrome P-450 CYP2C19 , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/therapy , Platelet Aggregation Inhibitors/administration & dosage , Platelet Aggregation Inhibitors/pharmacokinetics , Polymorphism, Genetic , Stents , Ticlopidine/administration & dosage , Ticlopidine/pharmacokinetics , Treatment Outcome
SELECTION OF CITATIONS
SEARCH DETAIL
...