RESUMO
Hyperfine parameters and the pressure dependence of the magnetic transition temperatures of FeRhGe2have been investigated. Sample has been prepared using high pressure-high temperature synthesis technique. FeRhGe2consists of two B20 structure phases with close lattice constants. The phase separation stays constant in the temperature range 4-300 K. The magnetic transition temperaturesTc1= 213 K andTc2= 135 K of FeRhGe2slightly increases with pressure in the range 0-4.5 GPa. We have compared this pressure dependence with some others compounds in the family Fe1-xRhxGe. The two phases in FeRhGe2have slightly different values of the hyperfine magnetic fields.
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Temperature dependent powder and single-crystal synchrotron diffraction, specific heat, magnetic susceptibility and small-angle neutron scattering experiments have revealed an anomalous response of MnGe. The anomaly becomes smeared out with decreasing Mn content in Mn1-x Co x Ge and Mn1-x Fe x Ge solid solutions. Mn spin state instability is discussed as a possible candidate for the observed effects.
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Equipment of field units or ine meaical service of the Armed Forces with modem medical complexes on the basis of pneumo-frame modules, and procedure of the use. On the basis of experience of medical supply in local wars and modern armed conflicts, when liquidating medical and sanitary disaster consequences the authors revealed the main organizational problems in army echelon of the medical service. It is shown that these problems can be solved by means of deployment of medical units and subunits. Requirements for means of deployment are defined. Present organic equipment is assessed. The authors showed advantages ofpneumo- framed modules, their tactic and technical characteristics, variants of the use when deploying army levels of field medical evacuation.
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Equipamentos Médicos Duráveis , Hospitais Militares , Medicina Militar , Equipamentos Médicos Duráveis/normas , Equipamentos Médicos Duráveis/provisão & distribuição , Hospitais Militares/organização & administração , Hospitais Militares/normas , Humanos , Medicina Militar/instrumentação , Medicina Militar/métodos , Medicina Militar/organização & administração , Medicina Militar/normasRESUMO
The state research and test institute of military medicine of the Ministry of Defence of the Russian Federation celebrates the 85th anniversary. The article is devoted to the anniversary of the newly reconstituted state research and test institute of Military Medicine of the Ministry of Defence of the Russian Federation. The institute was closed down in 2011 and worked exclusively as a structural subdivision of the Kirov Military Medical Academy for tests of ergonomic characteristics of a weapon and military equipment. Recreation of the institute allowed to engage highly qualified personnel and change the range of tasks, identified prospects of fundamental and applied researches in the field of development of hemostatic agents and anaesthetics, physiology of military work, medical robotics, development of technical means for medical services, and development of new medical technologies. The authors formulated prospects of development of the institution and its participation in the implementation of the primary tasks of the Medical Service to preserve and improve the health of military personnel.
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Pesquisa Biomédica/história , Medicina Militar/história , Aniversários e Eventos Especiais , História do Século XX , História do Século XXI , Humanos , Federação RussaRESUMO
Retroperitoneal surgical approach is the main component of operative intervention. This approach predetermines quality of surgical operation and the risk of intraoperative complications, an opportunity of their prevention. Lymphadenectomy is the unique method allowing authentically to confirm cancer in the lymph nodes and to evaluate a stage of disease. Endoscopicsurgical nephrectomy is the operation that keeps advantages of minimally invasive surgical approach in the majority of kidneys diseases without loss of quality of surgical treatment.
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Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Laparoscopia/métodos , Qualidade da Assistência à Saúde , Feminino , Humanos , Laparoscopia/efeitos adversos , Masculino , Estadiamento de NeoplasiasAssuntos
Carcinoma de Células Renais/cirurgia , Ponte de Artéria Coronária/métodos , Estenose Coronária/cirurgia , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Carcinoma de Células Renais/complicações , Estenose Coronária/complicações , Seguimentos , Humanos , Neoplasias Renais/complicações , Masculino , Pessoa de Meia-IdadeRESUMO
We report the basic physical properties of monoclinic Y8Co5 determined by means of magnetic susceptibility, electrical resistivity, and specific heat measurements. The crystal structure of Y8Co5 is monoclinic (P2(1)/c) with lattice parameters a = 7.0582(6) Å, b = 7.2894(6) Å, c = 24.2234(19) Å, and ß = 102.112(6)° as refined by using synchrotron powder x-ray diffraction data. The compound shows temperature independent paramagnetism with χ0 = 2.1 × 10(-3) emu mol(-1) and Sommerfeld parameter γ = 63 mJ mol(-1) K(-2). The calculated Wilson ratio for Y8Co5, R(W) = 1.4, is close to that expected for a free electron gas R(W) = 1. Low temperature resistivity under high pressure does not reveal superconductivity in this compound down to 1.2 K, up to hydrostatic pressures of 5.56 GPa. Band structure calculations (full-potential linearized augmented plane wave, FP-LAPW) derive the Stoner exchange interaction parameter S = 0.24, excluding magnetic behavior for Y8Co5.
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When antiferromagnetism and unconventional superconductivity coexist in CeRhIn(5) there is a significant temperature difference between resistively and thermodynamically determined transitions into the superconducting state. In this state, anisotropic transport near the superconducting transition reveals the emergence of textured superconducting planes that appear without a change in translational symmetry of the lattice. CeRhIn(5) is not unique in exhibiting these behaviors, indicating that textured superconductivity may be a general consequence of coexisting orders in correlated electron materials.
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Temperatura Baixa , Eletrocirurgia/instrumentação , Eletrocirurgia/métodos , Eletrodos , HumanosRESUMO
The lack of superconductivity in several candidate materials that exhibit a non-spin density wave quantum critical point has raised the question of whether the associated spectra of quantum fluctuations are beneficial to forming superconducting electron pairs. Here we discuss the possibility that the prototypical heavy-fermion antiferromagnet CeRhIn5 may be the first example of unconventional superconductors where superconductivity arises from Kondo-breakdown quantum criticality.
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An analysis of medical services of NATO and the Medical Service of the Armed Forces of the Russian Federation of modern technology deployment stages of medical evacuation (tents, inflatable structures, shelters, containers, medical armored vehicles, cars, etc.) is presented. Examples of their usage in isolated employment, usage in the group as a mobile medical stations and field hospitals in various conditions, the prospects and directions of development of technical means deployment of medical service are given.
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Hospitais Militares , Medicina Militar , Transporte de Pacientes , Hospitais Militares/organização & administração , Hospitais Militares/normas , Medicina Militar/instrumentação , Medicina Militar/métodos , Medicina Militar/organização & administração , Medicina Militar/normas , Federação Russa , Transporte de Pacientes/métodos , Transporte de Pacientes/organização & administração , Transporte de Pacientes/normasRESUMO
Presented data is about attendance means of deployment of field medical units and pieces of army-level medical services and disaster medicine Defense Ministry did not ensure compliance with requirements to create optimal conditions for highly effective work of the medical staff, placing the wounded, the use of modern aids and appliances. The prospects of creation of mobile unit for high-availability modular pre-fabricated on the basis of tent structures, pneumoconstructions and removable habitable bodies, containers, tents, pneumocovers till 2020 are analyzed. Livelihood systems provide armor protection against fragments, bullets, flames, damaging factors of chemical and biological weapons.
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Medicina de Desastres/instrumentação , Medicina de Desastres/métodos , Hospitais Militares , Medicina Militar/instrumentação , Medicina Militar/métodos , Unidades Móveis de Saúde , Medicina de Desastres/normas , Medicina de Desastres/tendências , Humanos , Medicina Militar/normas , Medicina Militar/tendênciasRESUMO
Paper is devoted to the history of creation of various types of field installations of the tent, mobile medical units and facilities, the experience of their usage in combat. An analysis of approaches to medical support of troops and equipment of the medical service in accordance with the changing nature of military operations in the XX-XI centuries is performed. Description of several generations of means taken to supply is given.
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Hospitais Militares/história , Medicina Militar/história , Medicina Militar/métodos , Unidades Móveis de Saúde/história , Transporte de Pacientes/história , Transporte de Pacientes/métodos , História do Século XX , História do Século XXI , Humanos , Unidades Móveis de Saúde/normasRESUMO
Pressure-dependent electrical resistivity and ac-calorimetry measurements on single crystals of the heavy-fermion antiferromagnet U(2)Zn(17) at pressures to 5.5 GPa reveal that the low temperature magnetic order changes above â¼3 GPa. The Neél temperature (T(N) = 9.7 K at ambient pressure) decreases slowly for pressures below 3 GPa, but above this pressure a new magnetic state develops at T(M)≈8.7 K. This magnetic phase becomes more stable with pressure increase (dT(M)/dP = 1 K GPa(-1), T(M) = 10.5 K at 5.3 GPa). The heavy-electron state in U(2)Zn(17) is robust against pressure--the electronic specific heat coefficient γ≈0.4 J mol(-1) K(-2) is nearly pressure independent for both magnetic phases. Magnetic ac-susceptibility measurements show that the pressure-induced state is not ferromagnetic.
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Compostos Férricos/antagonistas & inibidores , Compostos Férricos/química , Magnetismo , Compostos de Urânio/química , Compostos de Zinco/química , Modelos Moleculares , PressãoRESUMO
We synthesized tetragonal α-FeSe by melting a powder mixture of iron and selenium at high pressure. Subsequent annealing at normal pressure results in removing traces of hexagonal ß-FeSe, formation of a rather sharp transition to a superconducting state at T(c)â¼7 K, and the appearance of a magnetic transition near T(M) = 120 K. Resistivity and ac-susceptibility were measured on the annealed sample at hydrostatic pressure up to 4.5 GPa. A magnetic transition visible in ac-susceptibility shifts down under pressure and a resistive anomaly typical for a spin density wave (SDW) antiferromagnetic transition develops near the susceptibility anomaly. T(c), determined by the appearance of a diamagnetic response in susceptibility, increases linearly under pressure at a rate dT(c)/dP = 3.5 K GPa(-1). Below 1.5 GPa, the resistive superconducting transition is sharp, the width of transition does not change with pressure and, T(c), determined by a peak in dρ/dT, increases at a rate â¼3.5 K GPa(-1). At higher pressure, a giant broadening of the resistive transition develops. This effect cannot be explained by possible pressure gradients in the sample and is inherent to α-FeSe. The dependences dρ(T)/dT show a signature for a second peak above 3 GPa which is indicative of the appearance of another superconducting state in α-FeSe at high pressure. We argue that this second superconducting phase coexists with SDW antiferromagnetism in a partial volume fraction and originates from pairing of charge carriers from other sheets of the Fermi surface.
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Superconductivity without phonons has been proposed for strongly correlated electron materials that are tuned close to a zero-temperature magnetic instability of itinerant charge carriers. Near this boundary, quantum fluctuations of magnetic degrees of freedom assume the role of phonons in conventional superconductors, creating an attractive interaction that 'glues' electrons into superconducting pairs. Here we show that superconductivity can arise from a very different spectrum of fluctuations associated with a local (or Kondo-breakdown) quantum critical point that is revealed in isotropic scattering of charge carriers and a sublinear, temperature-dependent electrical resistivity. At this critical point, accessed by applying pressure to the strongly correlated, local-moment antiferromagnet CeRhIn(5), magnetic and charge fluctuations coexist and produce electronic scattering that is maximal at the optimal pressure for superconductivity. This previously unanticipated source of pairing glue opens possibilities for understanding and discovering new unconventional forms of superconductivity.
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The study has comparatively evaluated the effectiveness and safety of halothane, enflurane, and isoflurane in children during induction. Seventy hundred and eight patients aged 1-14 years who had ASA I-II anesthetic risks were examined. Gas induction was performed as monoanesthesia through the semi-open circuit with high gas flow (100% O2 6 l/min) in combination with halothane (n = 236), enflurane (n = 236), or isoflurane (n = 236) without N2O. The authors have compared the following criteria: the speed and comfort of induction, the parameters of hemodynamics and external respiration, and the rate of adverse reactions and complications during induction. The studies have established that in terms of comfort, safety, and the rate clinical effect achievement, the drugs of choice for gas induction in children are enflurane and, to a lesser extent, halothane. Gas induction with isoflurane should not be performed in children since the agent rather frequently exerts an irritant action on the upper airways, which reduces the speed of initial narcosis and increases the likelihood of one or another adverse reactions; however; it has advantages as a less hemodynamic effect.
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Anestesia por Inalação/métodos , Anestésicos Inalatórios , Enflurano , Halotano , Isoflurano , Adolescente , Anestésicos Inalatórios/efeitos adversos , Criança , Pré-Escolar , Enflurano/efeitos adversos , Halotano/efeitos adversos , Hemodinâmica/efeitos dos fármacos , Humanos , Lactente , Isoflurano/efeitos adversos , Segurança , Fatores de Tempo , Resultado do TratamentoRESUMO
The mixed-valence compound was investigated by electrical resistivity and ac specific heat at low temperatures and high pressures. At atmospheric pressure, its Kadowaki-Woods (KW) ratio A/gamma2 is 16 times smaller than the universal value RKW(=1.0x10(-5) microOmega.cm.mol2.K2.mJ-2), but sharply increases to 16.5RKW at 27 kbar. The pressure-induced change in the KW ratio and deviation from RKW are analyzed in terms of the change in f-orbital degeneracy N and carrier density n. This analysis is further supported by a dramatic change in residual resistivity rho0 near 25 kbar, where rho0 jumps by a factor of 7.