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1.
Polymers (Basel) ; 14(19)2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-36236083

RESUMO

Three-dimensional simulations of laminar flame propagating downwards the vertical surface of a rigid polyurethane slab heated by a radiative panel are presented and compared with the measurement data. The gas-phase model (ANSYS Fluent) allows for finite-rate volatile oxidation, soot formation and oxidation, emission, transfer, and absorption of thermal radiation. The solid-phase model Pyropolis considers heat transfer across the material layer and generation of combustible volatiles in thermal decomposition of the material. Kinetic model of material decomposition is derived to obey the microscale combustion calorimetry data for different heating rates. Transient behavior of propagating flame and pyrolysis zone, as well as spatial distributions of heat flux components, temperature, and mass burning rates over the specimen surface are examined. Variation of the thermal properties of the material during its thermal decomposition, as well as the specimen surface emissivity and reradiation are shown to be the important issues strongly affecting model predictions. Two distinct modes of counterflow flame spread, thermal and kinetic, are identified. In the thermal mode corresponding to fast chemistry in the gaseous flame, the flame propagation velocity is governed by the heating rate of the combustible material ahead of the flame front. Alternatively, in the kinetic mode, it is limited by the burning velocity of the volatile-air mixture forming ahead of the flame front. Simulation results are favorably compared with the measured propagation velocity.

2.
Artigo em Russo | MEDLINE | ID: mdl-36168691

RESUMO

The prevalence of affective disorders in patients with Parkinson's disease (PD) is significantly higher than in the general population of people of the same age. It is known that the effectiveness of antidepressants in PD with depressive disorder is lower than in patients with primary depression. For depression resistant to standard treatments, other therapeutic strategies are available. Transcranial magnetic stimulation (TMS) is one of the most popular and safe brain stimulation methods that has been successfully used to treat primary depression. The accumulation of experience in the use of TMS has made it possible to expand the application of the method to other diseases, including PD. The article provides literature data on the use of different TMS protocols for the treatment of depressive disorder in patients with PD.


Assuntos
Transtorno Depressivo , Doença de Parkinson , Encéfalo , Transtorno Depressivo/etiologia , Transtorno Depressivo/terapia , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Doença de Parkinson/terapia , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
3.
Space Sci Rev ; 218(1): 3, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35153338

RESUMO

EUSO-Balloon is a pathfinder for JEM-EUSO, the mission concept of a spaceborne observatory which is designed to observe Ultra-High Energy Cosmic Ray (UHECR)-induced Extensive Air Showers (EAS) by detecting their UltraViolet (UV) light tracks "from above." On August 25, 2014, EUSO-Balloon was launched from Timmins Stratospheric Balloon Base (Ontario, Canada) by the balloon division of the French Space Agency CNES. After reaching a floating altitude of 38 km, EUSO-Balloon imaged the UV light in the wavelength range ∼290-500 nm for more than 5 hours using the key technologies of JEM-EUSO. The flight allowed a good understanding of the performance of the detector to be developed, giving insights into possible improvements to be applied to future missions. A detailed measurement of the photoelectron counts in different atmospheric and ground conditions was achieved. By means of the simulation of the instrument response and by assuming atmospheric models, the absolute intensity of diffuse light was estimated. The instrument detected hundreds of laser tracks with similar characteristics to EASs shot by a helicopter flying underneath. These are the first recorded laser tracks measured from a fluorescence detector looking down on the atmosphere. The reconstruction of the direction of the laser tracks was performed. In this work, a review of the main results obtained by EUSO-Balloon is presented as well as implications for future space-based observations of UHECRs.

4.
Bull Exp Biol Med ; 171(3): 393-398, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34297295

RESUMO

We studied ultrastructure and vesicular structures in endothelial cells of myocardial micro-vessels in burn patients. Electron microscopy revealed a significant decrease in volume density of vesicular structures in the endotheliocytes of myocardial capillaries in patients with burn septicotoxemia. The observed structural signs of endothelial dysfunction revealed in this category of patients can be a promising area for further research and for the development of methods of pathogenetic correction of myocardial disorders in the case of burn injury.


Assuntos
Queimaduras/patologia , Capilares/ultraestrutura , Células Endoteliais/ultraestrutura , Miocárdio/ultraestrutura , Sepse/patologia , Adulto , Autopsia , Queimaduras/complicações , Capilares/patologia , Cavéolas/patologia , Cavéolas/ultraestrutura , Células Endoteliais/patologia , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Miocárdio/patologia , Sepse/complicações , Vesículas Transportadoras/patologia , Vesículas Transportadoras/ultraestrutura
5.
Zh Nevrol Psikhiatr Im S S Korsakova ; 119(1. Vyp. 2): 45-49, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31006791

RESUMO

AIM: To determine clinical and psychopathological features of anxiety-depressive disorders in patients with cerebral residual organic insufficiency. MATERIAL AND METHODS: One hundred and fourteen patients with anxiety-depressive disorders and cerebral residual-organic insufficiency were studied. Psychopathological, psychometric, statistical methods were used. RESULTS AND CONCLUSION: Asthenia was identified as a core syndrome in anxiety-depressive disorders developed in patients with cerebral residual-organic insufficiency. Severe anxiety and depression with somatization of symptoms were characteristic of the structure of affective pathology. The somatization of affect, interpersonal sensitivity, marked asthenic and autonomic disorders as well as negative attitudes about their own condition, abilities and activity were main features of affective disorders in patients with cerebral residual-organic insufficiency. Clinical characteristics of cerebral residual-organic insufficiency and the diversity of its manifestations, including the combination with mental disorders, determine the relevance of further research.


Assuntos
Encéfalo , Depressão , Transtornos do Humor , Ansiedade , Transtornos de Ansiedade , Astenia , Encéfalo/anormalidades , Encéfalo/fisiopatologia , Humanos
6.
Biosens Bioelectron ; 119: 48-54, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30098466

RESUMO

A CMOS-compatible ISFET with a Ta2O5 sensitive surface was developed. The structure was optimized for achieving high sensitivity using a subthreshold operation mode and by reducing the influence of the capacitances on the value of subthreshold swing. The developed ISFET was used as a basis for a biosensor for L-carnitine detection. To this end, carnitine acetyltransferase was immobilized on the ISFET sensitive surface. The immobilized enzyme was active (0.082 U/g model plate). The complete microsystem, consisting of a packaged chip, an immobilized enzyme and a microfluidic channel, detected L-carnitine at a range of 0.2-100 µM with a LOD of 0.2 µM. The biosensor response was linear in the range of 0.2-50 µM of L-carnitine with sensitivity 18.0 ±â€¯1.7 mV/µM. An experiment with artificial urine containing 1.3 µM L-carnitine showed that the proposed biosensor could be used on a real sample. Therefore, a new sensor specially optimized for biosensing CMOS-compatible ISFET structures and direct determination of L-carnitine with immobilized carnitine acetyltransferase was developed.


Assuntos
Técnicas Biossensoriais/métodos , Carnitina/urina , Enzimas Imobilizadas/metabolismo , Microfluídica , Urinálise/métodos , Carnitina Aciltransferases/metabolismo , Capacitância Elétrica , Humanos , Limite de Detecção , Urinálise/instrumentação
7.
Eksp Klin Gastroenterol ; (5): 36-41, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24501945

RESUMO

Despite the identical content of mebeverine hydrochloride, Duspatalin and Niaspam, produced by different technological processes, can't be considered interchangeable as they are known to have different clinical effect in case of various functional diseases of alimentary organs. Duspatalin is effective in relieving biliary disfunction symptoms, Oddy's sphincter hypertonicity in particular, but has little effect on intestinal dyskinesia. Niaspam is known to have little effect on biliary dyskinesia, but has a prominent positive clinical effect on intestinal dyskinesia.


Assuntos
Discinesia Biliar/tratamento farmacológico , Enteropatias/tratamento farmacológico , Parassimpatolíticos/administração & dosagem , Fenetilaminas/administração & dosagem , Adulto , Discinesia Biliar/fisiopatologia , Feminino , Humanos , Enteropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade
8.
Biofizika ; 58(6): 975-80, 2013.
Artigo em Russo | MEDLINE | ID: mdl-25486755

RESUMO

The classification of amino acid residues based on the events of contact formation between distinct amino acid and selected nucleotides was constructed. Thus, the most integral properties, that characterize interactions in organization of DNA-protein complexes, were used. We applied the Voronoi-Delaunay tessellation to draw statistics of contacts and area of contacts for the set included 1937 DNA-protein complexes. Similarities of amino acid residues have been searched for based on the comparison of corresponded rows and matrixes of contacts and areas of contacts. Nine measures of distance were used for estimation of rows similarity degree. The procedure of clustering amino acids in groups included three hierarchical and two nonhierarchical methods. A total tree was built using nine techniques of estimating distance with three hierarchical clustering methods. It was shown that clustering centers in the main groups are always constant while other relationships between objects vary. Clustering of binary associations was found for the most amino acids. Major classes of up to six amino acids correspond to the certain local structures of the polypeptide chain in the context of amino acid composition. These data should be taken into account when designing DNA-protein ligands.


Assuntos
Aminoácidos/química , Proteínas de Ligação a DNA/química , DNA/química , Aminoácidos/classificação , Proteínas de Ligação a DNA/classificação , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Modelos Moleculares , Nucleotídeos/química , Ligação Proteica
9.
Gig Sanit ; (6): 60-4, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24624824

RESUMO

This study is devoted to the investigation of possibility to use the total organic carbon as regulated index in drinking water as well as to the issues of hygienic regulation and harmonizing this index with the standards of other countries. Basing on the results of 3 years lasting investigation carried out by Municipal Unitary Enterprise "Vodokanal" of Yekaterinburg city permits to propose as the most informative and reliable index of the presence of organic substances in drinking water the content of total organic carbon in comparison with currently regulated permanganate oxidability, chemical and biochemical oxygen consumption.


Assuntos
Carbono , Água Potável , Exposição Ambiental/prevenção & controle , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio/métodos , Análise da Demanda Biológica de Oxigênio/normas , Carbono/efeitos adversos , Carbono/análise , Carbono/química , Água Potável/análise , Água Potável/química , Água Potável/normas , Humanos , Compostos Orgânicos , Federação Russa/epidemiologia , Águas Residuárias/análise , Águas Residuárias/estatística & dados numéricos , Qualidade da Água/normas
11.
Nature ; 456(7220): 362-5, 2008 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-19020615

RESUMO

Galactic cosmic rays consist of protons, electrons and ions, most of which are believed to be accelerated to relativistic speeds in supernova remnants. All components of the cosmic rays show an intensity that decreases as a power law with increasing energy (for example as E(-2.7)). Electrons in particular lose energy rapidly through synchrotron and inverse Compton processes, resulting in a relatively short lifetime (about 10(5) years) and a rapidly falling intensity, which raises the possibility of seeing the contribution from individual nearby sources (less than one kiloparsec away). Here we report an excess of galactic cosmic-ray electrons at energies of approximately 300-800 GeV, which indicates a nearby source of energetic electrons. Such a source could be an unseen astrophysical object (such as a pulsar or micro-quasar) that accelerates electrons to those energies, or the electrons could arise from the annihilation of dark matter particles (such as a Kaluza-Klein particle with a mass of about 620 GeV).

12.
Biofizika ; 53(3): 402-6, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18634311

RESUMO

A new method for the rigorous analysis of DNA-protein contacts has been developed on the basis of Voronoi tessellation. This method permits one to determine close neighbors on the atomic level and compute the area of contact by edges of Voronoi polyhedra. Based on the results of the study of 1109 protein-DNA complexes from PDB, it was demonstrated that about one third of the contacts are the contacts with positively charged Arg and Lys. There is distinct amino acid prevalence for nucleotides: for A - Pro; for T - His; for G - Asp; for C - Trp, Asp, Glu. Therefore, GC pairs prefer to interact with negatively charged residues, and alanine and methionine, whereas AT pairs prefer to interact with histidine and unpolar residues.


Assuntos
DNA/química , Modelos Moleculares , Proteínas/química , Aminoácidos/química , Bases de Dados de Proteínas , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nucleotídeos/química
13.
Philos Trans A Math Phys Eng Sci ; 366(1870): 1613-26, 2008 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-18192168

RESUMO

Carbon nanotubes have mechanical properties that are far in excess of conventional fibrous materials used in engineering polymer composites. Effective reinforcement of polymers using carbon nanotubes is difficult due to poor dispersion and alignment of the nanotubes along the same axis as the applied force during composite loading. This paper reviews the mechanical properties of carbon nanotubes and their polymer composites to highlight how many previously prepared composites do not effectively use the excellent mechanical behaviour of the reinforcement. Nanomechanical tests using atomic force microscopy are carried out on simple uniaxially aligned carbon nanotube-reinforced polyvinyl alcohol (PVA) fibres prepared using electrospinning processes. Dispersion of the carbon nanotubes within the polymer is achieved using a surfactant. Young's modulus of these simple composites is shown to approach theoretically predicted values, indicating that the carbon nanotubes are effective reinforcements. However, the use of dispersant is also shown to lower Young's modulus of the electrospun PVA fibres.


Assuntos
Nanotubos de Carbono/química , Adesividade , Resinas Compostas/química , Cristalização , Nanoestruturas/química , Nanotecnologia , Polímeros , Resistência à Tração
14.
Phys Rev Lett ; 98(23): 235003, 2007 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-17677912

RESUMO

Using a reductive perturbative expansion of the Vlasov-Maxwell (VM) equations for magnetized plasmas, a pseudodifferential equation of gradient type is derived for the nonlinear dynamics of mirror modes near the instability threshold. This model, where kinetic effects arise at a linear level only, develops a finite-time singularity, indicating the existence of a subcritical bifurcation. A saturation mechanism based on the local variations of the ion Larmor radius, is then phenomenologically supplemented. In contrast with previous models where saturation is due to the cooling of a population of trapped particles, the resulting equation correctly reproduces results of numerical simulations of VM equations, such as the development of magnetic humps from an initial noise, and the existence of stable large-amplitude magnetic holes both below and slightly above threshold.

15.
Clin Nephrol ; 68(1): 32-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17703833

RESUMO

Atherosclerotic renovascular disease commonly coexists with chronic kidney disease, and its optimal management remains unsettled. In this case report, we describe a 75-year-old woman with chronic kidney disease and critical atherosclerotic bilateral renal artery stenosis, who presented with a hypertensive emergency and developed acute renal failure following antihypertensive treatment. Bilateral percutaneous transluminal renal angioplasties (PTRA) with stent placement were performed and resulted in immediate recovery of renal function. The existing literature on this impressive response to PTRA is reviewed and discussed.


Assuntos
Injúria Renal Aguda/cirurgia , Angioplastia , Aterosclerose/cirurgia , Obstrução da Artéria Renal/cirurgia , Stents , Injúria Renal Aguda/complicações , Idoso , Feminino , Humanos , Recuperação de Função Fisiológica , Obstrução da Artéria Renal/complicações
17.
Klin Med (Mosk) ; 84(10): 35-9, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17201272

RESUMO

The results of 24-hour blood pressure monitoring (BPM) help to divide patients into therapeutic groups according to the leading hemodynamic mechanism offorming essential arterial hypertension (EAH). In patients with a mean day heart rate of > or =73 bpm antihypertensive therapy should begin with beta1-adrenoblockers when not contraindicated. In patients with a mean day heart rate of < or =73 bpm antihypertensive therapy may be started with preparations of other pharmaceutical groups. In this study, Plendil or Concor was administered as a chronotherapy; later their combination was used, and diuretics or ACE inhibitors were added when necessary. At any stage of the study, starting from the second week of therapy, if blood pressure (BP) was normal and there were ischemic episodes according to matched 24-hour BPM and ECG, Cardiket and, when not contraindicated, Aspirin, were added. The offered algorithm of choice of therapy made it possible to achieve a good antihypertensive effect in 84% of patients and a satisfactory effect in 7% of patients, which was accompanied by a tendency towards the shortening of total ischemia duration and lowering the frequency of myocardial hypokinesia. The effect of the therapy was poor only in 9% of patients, 2% of whom one left the study due to adverse reactions before BP was normalized. BP was normalized on the 8th week of treatment in 75% of patients. It is appropriate to include matched 24-hour BPM and ECG in the follow-up of patients with EAH and coronary artery disease upon discharge under the conditions of routine physical load. According to 24-hour BPM, mean day heart rate and total length of ischemia grow during this period due to an increase in physical and emotional load, which requires correction of the therapy.


Assuntos
Anti-Hipertensivos/uso terapêutico , Eletrocardiografia Ambulatorial/métodos , Eletrocardiografia , Hipertensão , Adulto , Idoso , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade
19.
Probl Tuberk Bolezn Legk ; (1): 13-6, 2005.
Artigo em Russo | MEDLINE | ID: mdl-15801628

RESUMO

The epidemiological indices and the methods for detecting tuberculosis have been analyzed in the children and adolescents of the Primorye Territory. It has been established that morbidity among children became stable by 2003 and was 23.6 per 100,000; in adolescents it remains high - 79.5 per 100,000 in 2003. The association of the role of different detection methods with the age group is now a specific feature of tuberculosis in children and adolescents. Mass tuberculin diagnosis plays a decisive role in the detection of tuberculosis only in children aged 5-7 years. In other age groups, tuberculosis is frequently identified at contacts with a physician. Radiation is the leading technique in detecting tuberculosis in adolescents. The consideration of the specific features of tuberculosis detection in relation to the age group assisted one in the selecting the most optimum strategy of tuberculosis control in children and adolescents.


Assuntos
Radiografia Torácica , Teste Tuberculínico , Tuberculose/diagnóstico , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Humanos , Lactente , Recém-Nascido , Morbidade/tendências , Estudos Retrospectivos , Federação Russa/epidemiologia , Tuberculose/epidemiologia
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