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1.
J Chem Phys ; 159(6)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37551816

RESUMO

Boron phosphide (BP) is a (super)hard semiconductor constituted of light elements, which is promising for high demand applications at extreme conditions. The behavior of BP at high temperatures and pressures is of special interest but is also poorly understood because both experimental and conventional ab initio methods are restricted to studying refractory covalent materials. The use of machine learning interatomic potentials is a revolutionary trend that gives a unique opportunity for high-temperature study of materials with ab initio accuracy. We develop a deep machine learning potential (DP) for accurate atomistic simulations of the solid and liquid phases of BP as well as their transformations near the melting line. Our DP provides quantitative agreement with experimental and ab initio molecular dynamics data for structural and dynamic properties. DP-based simulations reveal that at ambient pressure, a tetrahedrally bonded cubic BP crystal melts into an open structure consisting of two interpenetrating sub-networks of boron and phosphorous with different structures. Structure transformations of BP melt under compressing are reflected by the evolution of low-pressure tetrahedral coordination to high-pressure octahedral coordination. The main contributions to structural changes at low pressures are made by the evolution of medium-range order in the B-subnetwork and, at high pressures, by the change of short-range order in the P-subnetwork. Such transformations exhibit an anomalous behavior of structural characteristics in the range of 12-15 GPa. DP-based simulations reveal that the Tm(P) curve develops a maximum at P ≈ 13 GPa, whereas experimental studies provide two separate branches of the melting curve, which demonstrate the opposite behavior. Analysis of the results obtained raises open issues in developing machine learning potentials for covalent materials and stimulates further experimental and theoretical studies of melting behavior in BP.

2.
Vestn Otorinolaringol ; 86(4): 99-105, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34499456

RESUMO

Inflammation of the paranasal sinuses significantly reduces the quality of life of people and causes marked economic damage to society. The striking clinical picture of sinusitis has always forced doctors to study the disease, as evidenced by the first records of the anatomy and diseases of the paranasal sinuses by doctors in ancient Egypt more than 3.000 years BC. Sinusitis has been treated in different ways in different historical periods. Effective medication treatment appeared relatively recently and began to steadily replace the older instrumental methods, to which many people had a preconceived notion of invasiveness. However, many studies are showing the positive effect of active drainage methods and, moreover, there is data showing that the discomfort during such procedures is slightly higher than during dental treatment under local anesthesia. This article presents a review of the available scientific literature on the use of different treatments for bacterial rhinosinusitis at different historical stages, ranging from the first publications on puncture techniques to balloon dilatation and the modern approach to conservative treatment.


Assuntos
Seios Paranasais , Rinite , Sinusite , Doença Crônica , Humanos , Qualidade de Vida , Rinite/diagnóstico , Rinite/terapia , Sinusite/diagnóstico , Sinusite/terapia
3.
Sci Data ; 8(1): 218, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385471

RESUMO

The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâ†’vτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.

4.
Vestn Otorinolaringol ; 86(3): 110-117, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34269034

RESUMO

Inflammation of the paranasal sinuses significantly reduces the quality of life of people and causes marked economic damage to society. The striking clinical picture of sinusitis has always forced doctors to study the disease, as evidenced by the first records of the anatomy and diseases of the paranasal sinuses by doctors in ancient Egypt more than 3.000 years BC. Sinusitis has been treated in different ways in different historical periods. Effective medication treatment appeared relatively recently and began to steadily replace the older instrumental methods, to which many people had a preconceived notion of invasiveness. However, many studies are showing the positive effect of active drainage methods and, moreover, there is data showing that the discomfort during such procedures is slightly higher than during dental treatment under local anesthesia. This article presents a review of the available scientific literature on the use of different treatments for bacterial rhinosinusitis at different historical stages, ranging from the first publications on puncture techniques to balloon dilatation and the modern approach to conservative treatment.


Assuntos
Seios Paranasais , Rinite , Sinusite , Doença Crônica , Endoscopia , Humanos , Qualidade de Vida , Rinite/diagnóstico , Rinite/terapia , Sinusite/diagnóstico , Sinusite/terapia , Irrigação Terapêutica
5.
Vestn Otorinolaringol ; 85(1): 68-73, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32241993

RESUMO

Acute bacterial rhinosinusitis (ABRS) is one of the most common diseases in outpatient practice with a steady tendency to increase of complicated forms in recent years. The risk of antibiotic resistance makes it necessary to search for effective pathogenetic methods of ABRS treatment. OBJECTIVE: To evaluate the efficacy of inhalation therapy with compressor nebulizer using Fluimucil Antibiotic IT in the treatment of ABRS and acute laryngotracheitis in outpatient practice. MATERIAL AND METHODS: Patients with ABRS were divided into two sex- and age-matched groups of 26 people each. The first group was treated with 250 mg of Fluimucil Antibiotic IT inhalations by the use of Norditalia HI-NEB compressor nebulizer once a day. The second group was treated with amoxicillin/clavulanate 875 mg + 125 mg orally two times a day. RESULTS: In the first group, the cough disappeared significantly earlier (on day 5-6) than in the second group (on day 7-8). In the first group, nasal congestion also disappeared significantly earlier (on day 3-5) than in the second group (on day 4-6). There was no significant difference in the reduction of intoxication syndrome and nasal secretions in both groups. CONCLUSION: Local antibacterial and mucolytic therapy in the initial stages of ABRS and acute laryngotracheitis reduces rhinological symptoms and coughing, similar to systemic antibacterial therapy. The use of Fluimucil Antibiotic IT in the early stages of the treatment provides an opportunity to avoid systemic antibiotics, which reduces the risk of antibiotic resistance as well as side effects in patients.


Assuntos
Rinite/tratamento farmacológico , Sinusite/tratamento farmacológico , Doença Aguda , Antibacterianos/uso terapêutico , Humanos , Traqueia
6.
Vestn Otorinolaringol ; 85(6): 46-51, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33474917

RESUMO

The number of cases of acute bacterial rhinosinusitis (ABRS) in our country tends to increase. According to clinical guidelines of the Ministry of Health of the Russian Federation, nasal catheter drainage is used to treat ABRS, but not all ENT-doctors use this method in daily practice. Many of them use it empirically and obtain good results. GOAL: To study the experience of ENT-doctors using the YAMIK nasal catheter (NC) in their clinical practice. MATERIAL AND METHODS: To achieve the goal, a 16-question questionnaire was developed. Further, a survey of 30 ENT-doctors was conducted via e-mail. RESULTS AND DISCUSSION: The study showed a marked dispersion of data regarding the time of starting therapy, the number of necessary procedures, as well as the components of medication solutions administered to the paranasal sinuses. At the same time, the effectiveness of the method, in doctors' opinion, is very high (above 90%). The incorrect technique of NC application, absence of studies according to the principles of Good Clinical Practice (GCP), and constructive disadvantages of NC may be probable reasons for the method undervaluation. CONCLUSIONS: The prescription of procedures with NC to patients with ABRS is empirical and is probably related to the absence of clear indications for such treatment, data on its duration, and associated therapy. Consequently, research following GCP principles is required to develop an algorithm for treating ABSR with an NC. The development of a new design for an NC that will allow each ENT-doctor to learn the method is also appropriate.


Assuntos
Seios Paranasais , Rinite , Sinusite , Catéteres , Humanos , Rinite/diagnóstico , Rinite/terapia , Federação Russa , Sinusite/diagnóstico , Sinusite/terapia
7.
Sci Rep ; 9(1): 15325, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653919

RESUMO

Etching kinetics of swift heavy ions (SHI) tracks in olivine is investigated in frame of experimentally verified numerical approach. The model takes into account variation of induced chemical reactivity of the material around the whole ion trajectory with the nanometric accuracy. This enables a quantitative description of wet chemical etching of SHI tracks of different lengths and orientations towards to the sample surface. It is demonstrated that two different modes of etching, governed by diffusion of etchant molecules and by their reaction with the material must be observed in experiments using techniques with different resolution thresholds. Applicability limits of the optical microscopy for detection of heavy ion parameters by measuring of the lengthwise etching rates of the ion track are discussed.

8.
Phys Rev Lett ; 120(21): 211801, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29883136

RESUMO

The OPERA experiment was designed to study ν_{µ}→ν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.

9.
Artigo em Russo | MEDLINE | ID: mdl-12886627

RESUMO

The article deals with H. influenzae (different serotypes) carrier state and immune response before and after the administration of the vaccine "Act-HIB" to children of different age groups. Children aged up to 1 year and over 1 year have been found to differ in the dynamics of carrier state and in the concentration of antibodies of different classes to the antigens of this infective agent, which makes it necessary to carry out their early immunization with a view to ensure their protection from H. influenzae infection.


Assuntos
Infecções por Haemophilus/imunologia , Vacinas Anti-Haemophilus/imunologia , Haemophilus influenzae/imunologia , Imunidade , Fatores Etários , Portador Sadio/imunologia , Pré-Escolar , Infecções por Haemophilus/prevenção & controle , Vacinas Anti-Haemophilus/administração & dosagem , Humanos , Lactente
10.
Artigo em Russo | MEDLINE | ID: mdl-12449700

RESUMO

Comparative analysis of the diagnostic value of different laboratory methods in the diagnosis of H. influenzae b (Hib) pneumonia in children (bacteriological method, latex agglutination, counter immunoelectrophoresis, the passive hemagglutination test and the enzyme immunoassay (EIA) was carried out. EIA proved to be the most informative method for the diagnosing Hib pneumonia. EIA makes it possible to detect specific Hib antigens in different clinical materials in 48.8% of cases, as well as high titers of antibodies to mis infective agent in 61.7% of cases. The authors propose the unified criteria of the laboratory diagnosis of Hib infection in children.


Assuntos
Infecções por Haemophilus/diagnóstico , Haemophilus influenzae tipo b/isolamento & purificação , Pneumonia Bacteriana/diagnóstico , Adolescente , Testes de Aglutinação , Anticorpos Antibacterianos/análise , Antígenos de Bactérias/análise , Criança , Pré-Escolar , Infecções por Haemophilus/sangue , Infecções por Haemophilus/microbiologia , Haemophilus influenzae tipo b/imunologia , Humanos , Imunoeletroforese , Técnicas Imunoenzimáticas , Lactente , Pneumonia Bacteriana/sangue , Pneumonia Bacteriana/microbiologia , Fatores de Tempo
11.
Antibiot Khimioter ; 47(12): 20-6, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12733496

RESUMO

Results of clinical trial of the new pyrimidine derivative--ximedone are presented. The drug was administered per os 0.5 g x 4 times a day (0.5 h before meals). Total course dose achieved 60 g. Ximedone implementation for complex treatment of burns, trophic ulcer of lower limbs, different inflammations demonstrated positive results. Prophylaxy administration of the drug in abdominal surgery at acute appendix resulted with lower incidence of postoperative complications. High efficacy and good tolerability of the drug allows to recommend it for wide medical use.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Pirimidinas/uso terapêutico , Antibioticoprofilaxia , Queimaduras/tratamento farmacológico , Humanos
12.
Artigo em Russo | MEDLINE | ID: mdl-11881489

RESUMO

The role of influenza and parainfluenza viruses, respiratory syncytial viruses and adenoviruses in the etiological structure of morbidity in acute respiratory virus infections (ARVI) in children hospitalized during the 19 year period is analyzed. As the result of examination of 56,287 patients by direct immunofluorescent test, respiratory viruses were detected in 21% of cases. The seasonal character, periodicity and level of ARVI morbidity were established. According to medical records, in the 1990s ARVI took a more severe course in children than that observed in the 1980s. In addition, the data on morbidity among children regarding rotavirus infection and ARVI were found to be similar.


Assuntos
Adenoviridae , Orthomyxoviridae , Paramyxoviridae , Vírus Sinciciais Respiratórios , Infecções Respiratórias/virologia , Viroses/epidemiologia , Doença Aguda , Adenoviridae/isolamento & purificação , Infecções por Adenoviridae/epidemiologia , Adolescente , Criança , Pré-Escolar , Técnica Direta de Fluorescência para Anticorpo , Hospitais Pediátricos , Hospitais Urbanos , Humanos , Lactente , Influenza Humana/epidemiologia , Morbidade , Moscou/epidemiologia , Orthomyxoviridae/isolamento & purificação , Paramyxoviridae/isolamento & purificação , Infecções por Paramyxoviridae/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/epidemiologia , Estudos Retrospectivos , Estações do Ano
13.
Antibiot Khimioter ; 44(8): 12-7, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10494385

RESUMO

Pharmacotoxicological properties of ximedone, a new pyrimidine derivative, were studied experimentally on animals of various species. In the enteral regimen the drug had a favourable effect on thermal burns and postoperative cutaneous and gastric wounds. The results enabled to recommend ximedone for the clinical practice.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Queimaduras/tratamento farmacológico , Pirimidinas/uso terapêutico , Infecção da Ferida Cirúrgica/tratamento farmacológico , Adjuvantes Imunológicos/toxicidade , Animais , Avaliação Pré-Clínica de Medicamentos , Cobaias , Dose Letal Mediana , Camundongos , Complicações Pós-Operatórias/prevenção & controle , Pirimidinas/toxicidade , Coelhos , Ratos , Ratos Wistar , Cicatrização/efeitos dos fármacos
14.
Eksp Klin Farmakol ; 61(5): 10-2, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9854623

RESUMO

In experiments on rats it is found that propranolol in a dose of 2 mg/kg has a negative effect on higher integrative functions of the brain. Nootropics--pyracetam (200 mg/kg), AKF-94 (20 mg/kg), PIR-87-6-O (50 mg/kg) and actoprotector bemityl (40 mg/kg)--normalized orientative-trying behavior, memory, and emotionality of the animals. A possible mechanism of the drug action and prospects of their clinical application are discussed.


Assuntos
Anti-Hipertensivos/uso terapêutico , Encéfalo/efeitos dos fármacos , Atividade Nervosa Superior/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Propranolol/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Masculino , Nootrópicos/uso terapêutico , Ratos
15.
Eksp Klin Farmakol ; 60(3): 6-8, 1997.
Artigo em Russo | MEDLINE | ID: mdl-9324403

RESUMO

It was established that propranolol in a daily dose of 2 mg/kg causes disturbance of behavior of rats with arterial hypertension in the open field, deteriorates retention of memory traces in passive avoidance paradigm, and leads to the development of depression in the test for zoosocial interrelation. Administration of nootropic piracetam (200 kg/mg/24 h). as well as the original compounds ACP-94 (20 mg/kg/24 h) and PIR-87--6-0 (50-mg/kg/24 h) facilitates the correction of negative changes in the behavior and memory of hypertensive rats.


Assuntos
Anti-Hipertensivos/toxicidade , Comportamento Animal/efeitos dos fármacos , Hipertensão Renal/tratamento farmacológico , Memória/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Propranolol/toxicidade , Administração Oral , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/uso terapêutico , Ácido Aspártico/administração & dosagem , Ácido Aspártico/análogos & derivados , Ácido Aspártico/farmacologia , Aprendizagem da Esquiva/efeitos dos fármacos , Depressão/induzido quimicamente , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Hipertensão Renal/fisiopatologia , Masculino , Fármacos Neuroprotetores/administração & dosagem , Nootrópicos/administração & dosagem , Piracetam/farmacologia , Propranolol/administração & dosagem , Propranolol/uso terapêutico , Ratos , Ratos Endogâmicos SHR
16.
Eksp Klin Farmakol ; 59(4): 65-9, 1996.
Artigo em Russo | MEDLINE | ID: mdl-9026196

RESUMO

The method was proposed for experimental assessment of the drug psychotropic spectrum in rats under pair interaction conditions. The method was based on the recording and analysis of the main behavioral elements with a specially developed point scale. A study was done on spectra of the diazepam, amphetamine, and desipramine activity. The results of pharmacoethological analysis confirm the effectiveness of the proposed method for the assessment of psychotropic spectrum of the well known drugs (diazepam, amphetamine, desipramine), as well as new pharmacological compounds.


Assuntos
Comportamento Animal/efeitos dos fármacos , Psicofarmacologia/métodos , Comportamento Social , Animais , Etologia/métodos , Etologia/estatística & dados numéricos , Psicofarmacologia/estatística & dados numéricos , Ratos , Pesquisa/estatística & dados numéricos , Projetos de Pesquisa
18.
Vestn Khir Im I I Grek ; 151(7-12): 43-6, 1993.
Artigo em Russo | MEDLINE | ID: mdl-7975017

RESUMO

A new derivative of pyrimidine--Ximedon--was included in the complex treatment of 50 patients with trophic ulcers of lower extremities. The use of Ximedon resulted in shifts of homeostasis, of the cellular composition of the wound discharge, of metabolism of nucleic acids and activity of enzymes of the granulation tissue. Periods of the preoperative preparation of the patients became shorter. The immediate and long-term results obtained after such treatment were more stable.


Assuntos
Pirimidinas/uso terapêutico , Úlcera Varicosa/tratamento farmacológico , Idoso , Doença Crônica , Terapia Combinada , Tecido Conjuntivo/efeitos dos fármacos , Tecido Conjuntivo/fisiologia , Avaliação de Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade , Regeneração/efeitos dos fármacos , Úlcera Varicosa/sangue , Úlcera Varicosa/fisiopatologia
19.
Khirurgiia (Mosk) ; (4): 62-6, 1993 Apr.
Artigo em Russo | MEDLINE | ID: mdl-8084173

RESUMO

The authors studied xymedone, a new medicamentous agent from the group of pyrimidine derivatives. It was prescribed per os, 0.5 g taken three times daily. The experimental group consisted of 52 patients with IIIA and B degree thermal burns covering an area of 10 to 40%. The comparative appraisal was conducted with patients (60) treated by a complex of measures including methyluracil. Analysis of the obtained data showed a statistically significant, as compared to the controls, more rapid restoration of the peripheral blood parameters, decrease of C-reactive protein and level of sialic acid, and increase of total protein content and its gamma globulin fraction. Xymedone contributed to correction of blood dysproteinemia and produced an active effect on nucleic acid metabolism; the level of nucleic acids in the cells of the granulation tissue was much higher in the experimental group after treatment than in the controls. The normal ratio of T- and B-lymphocytes was restored and the phagocytosis indices grew. The production of coagulation and anticoagulation factors became normal, which coincided with cleaning of the granulations from fibrinous deposits and disappearance of the pathological predisposition to bleeding and easy damage of the granulation tissue. Under the effect of the agent the patients' appetite improved, the duration of the dehydration phase reduced, the rate of growth of microgranular granulations and epithelium increased, and the incidence of keloid cicatrices decreased. No unfavorable side effects of the agent were encountered. Xymedone is recommended for wide use in medical practice.


Assuntos
Antiulcerosos/uso terapêutico , Queimaduras/tratamento farmacológico , Pirimidinas/uso terapêutico , Uracila/análogos & derivados , Adolescente , Adulto , Idoso , Antiulcerosos/farmacologia , Linfócitos B/efeitos dos fármacos , Proteínas Sanguíneas/efeitos dos fármacos , Queimaduras/sangue , Queimaduras/imunologia , Queimaduras/fisiopatologia , Proteína C-Reativa/efeitos dos fármacos , Tecido de Granulação/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Ácido N-Acetilneuramínico , Fagocitose/efeitos dos fármacos , Pirimidinas/farmacologia , Ácidos Siálicos/sangue , Linfócitos T/efeitos dos fármacos , Uracila/farmacologia , Uracila/uso terapêutico , Cicatrização/efeitos dos fármacos
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