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1.
Phys Rev E ; 108(4-1): 044119, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37978711

RESUMO

We investigate analytically and numerically a system of clusters evolving via collisions with clusters of minimal mass (monomers). Each collision either leads to the addition of the monomer to the cluster or the chipping of a monomer from the cluster, and emerging behaviors depend on which of the two processes is more probable. If addition prevails, monomers disappear in a time that scales as lnN with the total mass N≫1, and the system reaches a jammed state. When chipping prevails, the system remains in a quasistationary state for a time that scales exponentially with N, but eventually, a giant fluctuation leads to the disappearance of monomers. In the marginal case, monomers disappear in a time that scales linearly with N, and the final supercluster state is a peculiar jammed state; i.e., it is not extensive.

2.
Phys Rev E ; 103(4): L040101, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34005914

RESUMO

In aggregation-fragmentation processes, a steady state is usually reached. This indicates the existence of an attractive fixed point in the underlying infinite system of coupled ordinary differential equations. The next simplest possibility is an asymptotically periodic motion. Never-ending oscillations have not been rigorously established so far, although oscillations have been recently numerically detected in a few systems. For a class of addition-shattering processes, we provide convincing numerical evidence for never-ending oscillations in a certain region U of the parameter space. The processes which we investigate admit a fixed point that becomes unstable when parameters belong to U and never-ending oscillations effectively emerge through a Hopf bifurcation.

3.
Phys Rev E ; 98(1-1): 012109, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30110817

RESUMO

We report surprising steady oscillations in aggregation-fragmentation processes. Oscillating solutions are observed for the class of aggregation kernels K_{i,j}=i^{ν}j^{µ}+j^{ν}i^{µ} homogeneous in masses i and j of merging clusters and fragmentation kernels, F_{ij}=λK_{ij}, with parameter λ quantifying the intensity of the disruptive impacts. We assume a complete decomposition (shattering) of colliding partners into monomers. We show that an assumption of a steady-state distribution of cluster sizes, compatible with governing equations, yields a power law with an exponential cutoff. This prediction agrees with simulation results when θ≡ν-µ<1. For θ=ν-µ>1, however, the densities exhibit an oscillatory behavior. While these oscillations decay for not very small λ, they become steady if θ is close to 2 and λ is very small. Simulation results lead to a conjecture that for θ<1 the system has a stable fixed point, corresponding to the steady-state density distribution, while for any θ>1 there exists a critical value λ_{c}, such that for λ<λ_{c}, the system has an attracting limit cycle. This is rather striking for a closed system of Smoluchowski-like equations, lacking any sinks and sources of mass.

4.
Sci Rep ; 8(1): 7053, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728585

RESUMO

The depletions of potassium (K) and sodium (Na) in samples from planetary interiors have long been considered as primary evidence for their volatile behavior during planetary formation processes. Here, we use high-pressure experiments combined with laser ablation analyses to measure the sulfide-silicate and metal-silicate partitioning of K and Na at high pressure (P) - temperature (T) and find that their partitioning into metal strongly increases with temperature. Results indicate that the observed Vestan and Martian mantle K and Na depletions can reflect sequestration into their sulfur-rich cores in addition to their volatility during formation of Mars and Vesta. This suggests that alkali depletions are not affected solely by incomplete condensation or partial volatilization during planetary formation and differentiation, but additionally or even primarily reflect the thermal and chemical conditions during core formation. Core sequestration is also significant for the Moon, but lunar mantle depletions of K and Na cannot be reconciled by core formation only. This supports the hypothesis that measured isotopic fractionations of K in lunar samples represent incomplete condensation or extensive volatile loss during the Moon-forming giant impact.

5.
Phys Chem Chem Phys ; 19(37): 25401-25413, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28894870

RESUMO

Density functional B3LYP/6-31G(d) and ab initio G3(MP2,CC) calculations have been carried out to determine thermal rate constants of direct H abstraction reactions from four- and five-ring polycyclic aromatic hydrocarbons (PAH) chrysene and benzo[a]pyrene by various radicals abundant in combustion flames, such as H, CH3, C3H3, and OH, using transition state theory. The results show that the H abstraction reactions with OH have the lowest barriers of ∼4 kcal mol-1, followed by those with H and CH3 with barriers of 16-17 kcal mol-1, and then with propargyl radicals with barriers of 24-26 kcal mol-1. Thus, the OH radical is predicted to be the fastest H abstractor from PAH. Even at 2500 K, the rate constant for H abstraction by H is still 34% lower than the rate constant for H abstraction by OH. The reaction with H is calculated to have rate constants 35-19 times higher than those for the reaction with CH3 due to a more favorable entropic factor. The reactions of H abstraction by C3H3 are predicted to be orders of magnitude slower than the other reactions considered and their equilibrium is strongly shifted toward the reactants, making propargyl an inefficient H abstractor from the aromatics. The calculations showed strong similarity of the reaction energetics in different H abstraction positions of benzo[a]pyrene and chrysene within armchair and zigzag edges in these molecules, but clear distinction between the armchair and zigzag sites. The zigzag sites appear to be more reactive, with H abstraction rate constants by H, CH3, and OH being respectively 37-42%, a factor of 2.1, and factors of 8-9 higher than the corresponding rate constants for the H abstraction reactions from armchair sites. Although the barrier heights for the two types of edges are similar, the entropic factor makes zigzag sites more favorable for H abstraction. Rate expressions have been generated for all studied reactions with the goal to rectify current combustion kinetics mechanisms.

6.
Phys Rev Lett ; 119(26): 260601, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29328699

RESUMO

We observe never-ending oscillations in systems undergoing collision-controlled aggregation and shattering. Specifically, we investigate aggregation-shattering processes with aggregation kernels K_{i,j}=(i/j)^{a}+(j/i)^{a} and shattering kernels F_{i,j}=λK_{i,j}, where i and j are cluster sizes, and parameter λ quantifies the strength of shattering. When 0≤a<1/2, there are no oscillations, and the system monotonically approaches a steady state for all values of λ; in this region, we obtain an analytical solution for the stationary cluster size distribution. Numerical solutions of the rate equations show that oscillations emerge in the 1/2

7.
Voen Med Zh ; 337(1): 67-75, 2016 Jan.
Artigo em Russo | MEDLINE | ID: mdl-27120956

RESUMO

The first field therapy department in our country was established in the S.M.Kirov Military Medical Academy in November, 1955. The new department was established by merging of academical Department's of military toxicology, nuclear weapon and field therapy course, taught in Hospital Therapy Department. The new department was imposed as teaching and research center of organizational issues of field therapy, pathology and clinic of radiation injuries and injuries due to chemical agents. Scientific researches were also conducted on the same direction. Department was headed by outstanding field therapist such as Ivanosvky B.D., Zakrzhevsky E.B., Gembitsky E.V., Alexeev G.I., Shishmarev Yu.N, Sosukin A.E. Since 2010 the head of department is Khalimov Yu.Sh. Over the last 60 years of its activity department has became a scientific and academic center on field therapy, alma mater of specialists on clinical radiology, clinical toxicology, military professional pathology, and organization of therapeutic medicine for the Armed Forces of the Russian Federation and other foreign countries. Department became famous as in our country as outside. Today department answers neccessary requirements for scientific-and-research work and successful training and professional improvement of the army and navy physicians.


Assuntos
Academias e Institutos/história , Educação de Pós-Graduação em Medicina/história , Medicina Militar/educação , Medicina Militar/história , Aniversários e Eventos Especiais , História do Século XX , História do Século XXI , Humanos
8.
Nature ; 507(7491): 221-4, 2014 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-24622201

RESUMO

The ultimate origin of water in the Earth's hydrosphere is in the deep Earth--the mantle. Theory and experiments have shown that although the water storage capacity of olivine-dominated shallow mantle is limited, the Earth's transition zone, at depths between 410 and 660 kilometres, could be a major repository for water, owing to the ability of the higher-pressure polymorphs of olivine--wadsleyite and ringwoodite--to host enough water to comprise up to around 2.5 per cent of their weight. A hydrous transition zone may have a key role in terrestrial magmatism and plate tectonics, yet despite experimental demonstration of the water-bearing capacity of these phases, geophysical probes such as electrical conductivity have provided conflicting results, and the issue of whether the transition zone contains abundant water remains highly controversial. Here we report X-ray diffraction, Raman and infrared spectroscopic data that provide, to our knowledge, the first evidence for the terrestrial occurrence of any higher-pressure polymorph of olivine: we find ringwoodite included in a diamond from Juína, Brazil. The water-rich nature of this inclusion, indicated by infrared absorption, along with the preservation of the ringwoodite, is direct evidence that, at least locally, the transition zone is hydrous, to about 1 weight per cent. The finding also indicates that some kimberlites must have their primary sources in this deep mantle region.

9.
Anesteziol Reanimatol ; (3): 43-50, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24340996

RESUMO

The article deals with review of 78 patients of rehabilitation toxicological unit. The patients received resuscitation and detoxification. All patients were divided into three groups; 1st group--patients after poisoning with psychopharmaceuticals, 2nd group--patients after poisoning with cauterizing liquids and 3rd group--patients with encephalopathy after poisoning with neurotoxin (psychopharmaceuticals, narcotics and ethanol). Disorders of rheology, haemostasis and endotoxicosis accrued in all groups. These disorders were a signs of the erythrocytes and platelets aggregation developing and viscoelasticity disorder. Homeostasis changes during rehabilitation period need an accurate diagnostics for purposeful treatment of the defined disorders.


Assuntos
Queimaduras Químicas/reabilitação , Homeostase/efeitos dos fármacos , Síndromes Neurotóxicas/reabilitação , Pneumonia/reabilitação , Intoxicação/reabilitação , Doença Aguda , Viscosidade Sanguínea/efeitos dos fármacos , Queimaduras Químicas/sangue , Queimaduras Químicas/etiologia , Cáusticos/intoxicação , Agregação Eritrocítica/efeitos dos fármacos , Etanol/intoxicação , Humanos , Entorpecentes/intoxicação , Síndromes Neurotóxicas/sangue , Síndromes Neurotóxicas/etiologia , Agregação Plaquetária/efeitos dos fármacos , Pneumonia/sangue , Pneumonia/etiologia , Intoxicação/sangue , Intoxicação/complicações , Psicotrópicos/intoxicação
10.
Voen Med Zh ; 334(6): 36-42, 2013 Jun.
Artigo em Russo | MEDLINE | ID: mdl-24000636

RESUMO

The authors suggested the main problems solved by the military field therapy: development, scientific rationale, systematic improvement and practical application of the organizational form of first aid for the wounded in conditions of combat actions; research on the etiology, pathogenesis and clinical picture of states caused by effect of weapon of mass destruction (nuclear weapon, chemical weapon, etc); development of methods of diagnosis, prophylaxis and treatment of the abovementioned states; research of the pattern, clinical progression and treatment of somatization disorders in conditions of combat and casual activity of troops, analysis of morbidity among the troops and development of prophylaxis;formulation of military-medical questionnaire and development of the system of rehabilitation for the wounded. Searching for innovative methods for solving the problems of military field therapy is the current problem. Modern warfare changed the concept of delivery of health care, effectiveness of evacuative actions, training of medical personnel and medical maintaining. The authors came to conclusion that qualitative technology breakthrough in development of military medicine and military field therapy would not happen without strategic understanding and learning of prospect technologies.


Assuntos
Hospitais Militares/organização & administração , Hospitais Militares/normas , Hospitais Militares/tendências , Medicina Militar/organização & administração , Medicina Militar/normas , Medicina Militar/tendências , Feminino , Humanos , Masculino
11.
Klin Lab Diagn ; (2): 10-2, 2013 Feb.
Artigo em Russo | MEDLINE | ID: mdl-23808001

RESUMO

The sampling consisted of 22 patients with extensive burns with total affected area from 20% to 84% of body surface and with deep burns area from 10% to 40%. The suppurative complications in the form of sepsis were diagnosed in 10 and the transitory bacteremia in 12 victims. The total and effective concentration of albumin, the content of medium molecular peptides in dynamics at 1-3, 7, 14 and 21 days from the moment of trauma were detected to objectively evaluate the endogenic intoxication. The degree of intensity of endogenic intoxication was studied using such integral indicator as effective utilization factor In patients with extensive burns the endogenic intoxication was diagnosed on the basis of total and effective concentration of albumin and increase of content of medium molecular peptides. However the detection of endogenic intoxication of the basis of effective utilization factor is a more informative as compared with the analysis of these indicators separately and, hence, it promote the prescription of more appropriate disintoxication therapy its effectiveness evaluation including.


Assuntos
Queimaduras/complicações , Endotoxemia/etiologia , Albumina Sérica/metabolismo , Índices de Gravidade do Trauma , Adulto , Idoso , Bacteriemia/sangue , Bacteriemia/etiologia , Bacteriemia/mortalidade , Queimaduras/sangue , Queimaduras/mortalidade , Endotoxemia/sangue , Endotoxemia/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/sangue , Pneumonia Bacteriana/etiologia , Pneumonia Bacteriana/mortalidade , Sepse/sangue , Sepse/etiologia , Sepse/mortalidade , Albumina Sérica/análise , Adulto Jovem
12.
Voen Med Zh ; 334(12): 39-45, 2013 Dec.
Artigo em Russo | MEDLINE | ID: mdl-24738280

RESUMO

National toxicology school of the Kirov Military Medical Academy, demonstrates the unity of clinical and experimental approaches related to one purpose throughout its history--saving human life and health from exposure to toxic substances of chemical nature. For more than three centuries the russian science of toxicology has been steadily developing, often ahead of the world science. It helped to create the means of protection and develop methods of treatment for chemical lesions. Currently, toxicology departments of military field therapy and military toxicology and medical protection are actively involved in the current study of military medicine, restructuring policy to provide toxicological aid in the Armed Forces, the development and introduction of Innovative methods of diagnosis and treatment of victims of toxicological etiology.


Assuntos
Academias e Institutos/história , Medicina Militar , Faculdades de Medicina , Toxicologia , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Medicina Militar/educação , Medicina Militar/história , Medicina Militar/tendências , Faculdades de Medicina/história , Faculdades de Medicina/tendências , Toxicologia/educação , Toxicologia/história , Toxicologia/tendências
13.
J Nanosci Nanotechnol ; 12(9): 7562-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23035517

RESUMO

A mechanism of unidirectional exchange anisotropy formation at thermo-magnetic treatment of permalloy-manganese bilayers has been studied. A shift of hysteresis loops appears at annealing beginning from 230 degrees C. The maximal exchange field of 155 Oe is reached after the 250 degrees C annealing for 2 h. As demonstrated by transmission electron microscopy, the exchange bias and the coercivity growth result from an ordered anti-ferromagnetic NiFeMn phase formation due to the diffusion interaction of permalloy and manganese at annealing.

14.
Voen Med Zh ; 333(8): 73-8, 2012 Aug.
Artigo em Russo | MEDLINE | ID: mdl-23012786

RESUMO

On August 18, 2012, 90 years have passed since the birth of the former head of the Military field therapy Department of The Military-Medical Academy named after S. M. Kirov--the main radiologist of the Ministry of Defence of Russian Federation, the corresponding member of the Soviet Union Academy of Medical Science and the Russian Academy of Medical Science, the major- general of a medical service G. I. Alekseyev, who had been working in the department since its foundation till the last day of his life. Being the head of the department for twelve years, G. I. Alekseyev made a considerable contribution to the formation and development of native military radiology, training of medical and scientific skilled specialists. Professor G. I. Alekseyev's scientific ideas and views in the sphere of radiology were realized and developed in further educational, research and medical work of the department. Nowadays the staff of the Military field therapy Department remembers G. I. Alekseyev with special gratitude and appreciation and successfully realizes his ideas and plans in work.


Assuntos
Academias e Institutos/história , Medicina Militar/história , Radiologia/história , Aniversários e Eventos Especiais , História do Século XX , História do Século XXI , Humanos , Federação Russa
15.
Klin Lab Diagn ; (5): 20-2, 2012 May.
Artigo em Russo | MEDLINE | ID: mdl-22834152

RESUMO

The experimental samplings consisted of 25 patients with severe course of hypertension disease in aggregate with atherogenic carotid stenosis before and after carotid endarterectomy and 21 donors. The study was organized to analyze in lipid profile blood serum the content of malonic dialdehyde, ceruloplasmin, alpha-tocopherol, nitric oxide and angiotensin converting enzyme. The study established that in patients took place a reliably increased level of malonic dialdehyde, ceruloplasmin, alpha-tocopherol, nitric oxide and angiotensin converting enzyme. The patients with this pathology have a reliable positive correlation between the concentration of malonic dialdehydeand lipoproteids of very low density (r = 0.51), malonic dialdehyde and triglycerides (r = 0.36), malonic dialdehyde and cholesterol (r = 0.3). This data confirms the important role of peroxidation of lipids in the development of atherosclerosis. Therefore, the enhancement of oxidation stress and expressed dislipoproteidemia are established in patients with hypertension disease with carotids atherosclerosis as a background. This result testifies the pathogenic significance of these phenomena in the mechanisms of homeostasis disorders.


Assuntos
Estenose das Carótidas/sangue , Hipertensão/sangue , Peroxidação de Lipídeos , Estresse Oxidativo , Idoso , Estenose das Carótidas/complicações , Estenose das Carótidas/cirurgia , Ceruloplasmina/metabolismo , Endarterectomia das Carótidas , Feminino , Humanos , Hipertensão/complicações , Hipertensão/cirurgia , Lipoproteínas VLDL/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Peptidil Dipeptidase A/sangue , alfa-Tocoferol/sangue
16.
Voen Med Zh ; 333(2): 24-32, 2012 Feb.
Artigo em Russo | MEDLINE | ID: mdl-22558849

RESUMO

Modern concept of medical-prophylactic measures in the time of mass radiation affection is presented in the present article. Moreover the past changes in organization-regular structure of medical service of the Armed Forces of the Russian Federation and appearance of new time-board equipment were taken into account. Recommendations about the rendering of all types of therapeutic aid on all stages of medical evacuation--first, premedical, medical assistance, qualified and specialized--are given.


Assuntos
Medicina Militar , Lesões por Radiação/terapia , Transporte de Pacientes , Humanos , Medicina Militar/métodos , Medicina Militar/organização & administração , Medicina Militar/normas , Saúde Radiológica/métodos , Saúde Radiológica/organização & administração , Saúde Radiológica/normas , Federação Russa , Transporte de Pacientes/métodos , Transporte de Pacientes/organização & administração , Transporte de Pacientes/normas
17.
Voen Med Zh ; 332(8): 36-42, 2011 Aug.
Artigo em Russo | MEDLINE | ID: mdl-22164984

RESUMO

In a review of the literature addresses the causes, characteristics of the purulent process of the hand, the questions of treatment of purulent diseases of the hand, methods of anesthesia and rehabilitation of the patients with this pathology. The typical mistakes in the delivery of health care of this category of patients.


Assuntos
Mãos , Infecções/patologia , Infecções/terapia , Erros Médicos/prevenção & controle , Humanos
18.
Voen Med Zh ; 331(11): 20-4, 2010 Nov.
Artigo em Russo | MEDLINE | ID: mdl-21395155

RESUMO

The article is concerned with the study of use of physical factors in the treatment of chronic lymphphleboid failure of lower limbs. As a result, it was able to show a significant positive dynamic under the complex approach of treating this disease. In patients with chronic lymphphleboid failure of lower limbs justified individual tactics, based on the use of a wide range of modern medicines, physical therapy techniques, therapeutic exercises, lymphatic massage of the lower limbs. This leads to early rehabilitation and improvement of quality of patients' life.


Assuntos
Extremidade Inferior/irrigação sanguínea , Linfedema/terapia , Modalidades de Fisioterapia , Síndrome Pós-Trombótica/terapia , Varizes/terapia , Adulto , Terapia Combinada , Procedimentos Endovasculares/métodos , Feminino , Humanos , Linfedema/diagnóstico , Linfedema/reabilitação , Linfedema/cirurgia , Masculino , Síndrome Pós-Trombótica/diagnóstico , Síndrome Pós-Trombótica/reabilitação , Síndrome Pós-Trombótica/cirurgia , Resultado do Tratamento , Varizes/diagnóstico , Varizes/reabilitação , Varizes/cirurgia
19.
Klin Lab Diagn ; (4): 15-6, 2009 Apr.
Artigo em Russo | MEDLINE | ID: mdl-19514328

RESUMO

The time course of changes in the serum levels of average mass molecules and malondialdehyde in patients with pelvic peritonitis was studied within two weeks after surgery. The values of the above indices of endogenous intoxication (EI) were found to be 1.3-2.9 times higher than the normal values almost throughout the follow-up (p < 0.05). An integral EI coefficient (EIC) including relative (as compared with the normal values) EI indices was proposed to evaluate the magnitude of EI. In patients with pelvic peritonitis, EIC was established to be 2.9-4.8 times greater than the normal values (p < 0.05) in all follow-up periods. Thus, the application of EIC enhances the sensitivity of EI diagnosis in patients with pelvic peritonitis as compared with that in the determination of individual EI indices.


Assuntos
Doença Inflamatória Pélvica/diagnóstico , Peritonite/diagnóstico , Adulto , Proteínas Sanguíneas/análise , Feminino , Humanos , Peroxidação de Lipídeos , Malondialdeído/sangue , Pessoa de Meia-Idade , Doença Inflamatória Pélvica/sangue , Peritonite/sangue , Peritonite/metabolismo
20.
Klin Lab Diagn ; (5): 16-8, 2009 May.
Artigo em Russo | MEDLINE | ID: mdl-19537112

RESUMO

Determination of the serum content of average molecular weight peptides that are markers of endogenous intoxication in the burnt, patients with acute poisoning by psychopharmacologicals, pancreatic necrosis, generalized peritonitis, small pelvic inflammation may serve as an additional laboratory criteria for rating the severity of critical conditions, predicting the development of complications, the outcome of diseases, and evaluating the efficiency of treatment.


Assuntos
Serviços Médicos de Emergência/métodos , Endotoxemia/sangue , Peptídeos/sangue , Queimaduras/sangue , Queimaduras/complicações , Queimaduras/terapia , Endotoxemia/etiologia , Endotoxemia/prevenção & controle , Humanos , Peso Molecular , Pancreatite Necrosante Aguda/sangue , Pancreatite Necrosante Aguda/complicações , Pancreatite Necrosante Aguda/terapia , Peritonite/sangue , Peritonite/complicações , Peritonite/terapia , Intoxicação/sangue , Intoxicação/complicações , Intoxicação/terapia , Valor Preditivo dos Testes , Índice de Gravidade de Doença
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