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1.
Rev Sci Instrum ; 91(8): 085109, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32872955

RESUMO

Here, we present an integrated ultra-high vacuum apparatus-named MBE-Cluster -dedicated to the growth and in situ structural, spectroscopic, and magnetic characterization of complex materials. Molecular Beam Epitaxy (MBE) growth of metal oxides, e.g., manganites, and deposition of the patterned metallic layers can be fabricated and in situ characterized by reflection high-energy electron diffraction, low-energy electron diffraction, Auger electron spectroscopy, x-ray photoemission spectroscopy, and azimuthal longitudinal magneto-optic Kerr effect. The temperature can be controlled in the range from 5 K to 580 K, with the possibility of application of magnetic fields H up to ±7 kOe and electric fields E for voltages up to ±500 V. The MBE-Cluster operates for in-house research as well as user facility in combination with the APE beamlines at Sincrotrone-Trieste and the high harmonic generator facility for time-resolved spectroscopy.

2.
Opt Express ; 26(13): 16352-16364, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119468

RESUMO

We consider emitting nanoparticles in dielectric nanocomposites with varying refractive index contrast and geometry. For that we develop a simple and universal method to calculate the emission enhancement in nanocomposites that employs solely the calculation of the effective refractive index and electric field distributions from three quasistatic calculations with orthogonal polarizations. The method is exemplified for dilute nanocomposites without electromagnetic interaction between emitting particles as well as for dense nanocomposites with strong particle interaction. We show that the radiative decay in dielectric nanocomposites is greatly affected by the shape and arrangement of its constituents and give guidelines for larger enhancement.

3.
Sci Rep ; 7(1): 13916, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29066840

RESUMO

Super-Planckian near-field radiative heat transfer allows effective heat transfer between a hot and a cold body to increase beyond the limits long known for black bodies. Until present, experimental techniques to measure the radiative heat flow relied on steady-state systems. Here, we present a dynamic measurement approach based on the transient plane source technique, which extracts thermal properties from a temperature transient caused by a step input power function. Using this versatile method, that requires only single sided contact, we measure enhanced radiative conduction up to 16 times higher than the blackbody limit on centimeter sized glass samples without any specialized sample preparation or nanofabrication.

4.
Eksp Klin Farmakol ; 79(2): 34-9, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27416681

RESUMO

The influence of angioprotector and endothelium-protector drugs pentoxifylline and unifuzol as components of supportive therapy on the efficacy of combined cytostatic treatment has been experimentally studied. It is established that pentoxifylline and unifuzol do not affect the antitumor and antimetastatic activity of doxorubicin and cyclophosphan with respect to Pliss lymphosarcoma and Walker 256 carcinosarcoma, and in some cases even potentiate the effect of cytostatic therapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácido Argininossuccínico/farmacologia , Carcinoma 256 de Walker/tratamento farmacológico , Citostáticos/farmacologia , Linfoma não Hodgkin/tratamento farmacológico , Pentoxifilina/farmacologia , Animais , Carcinoma 256 de Walker/patologia , Proliferação de Células/efeitos dos fármacos , Ciclofosfamida/farmacologia , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Linfoma não Hodgkin/patologia , Masculino , Ratos , Ratos Wistar , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nat Commun ; 7: 11809, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27263653

RESUMO

Control of thermal radiation at high temperatures is vital for waste heat recovery and for high-efficiency thermophotovoltaic (TPV) conversion. Previously, structural resonances utilizing gratings, thin film resonances, metasurfaces and photonic crystals were used to spectrally control thermal emission, often requiring lithographic structuring of the surface and causing significant angle dependence. In contrast, here, we demonstrate a refractory W-HfO2 metamaterial, which controls thermal emission through an engineered dielectric response function. The epsilon-near-zero frequency of a metamaterial and the connected optical topological transition (OTT) are adjusted to selectively enhance and suppress the thermal emission in the near-infrared spectrum, crucial for improved TPV efficiency. The near-omnidirectional and spectrally selective emitter is obtained as the emission changes due to material properties and not due to resonances or interference effects, marking a paradigm shift in thermal engineering approaches. We experimentally demonstrate the OTT in a thermally stable metamaterial at high temperatures of 1,000 °C.

6.
Eksp Klin Farmakol ; 79(11): 11-14, 2016.
Artigo em Russo | MEDLINE | ID: mdl-29791109

RESUMO

Specific pharmacologic activity of sodium-L-arginine succinate (unifusol) was studied on endothelium dysfunction model (EDM) in rats. EDM was induced by daily administration of N-nitro-L-arginine methyl ether (L-NAME). The effectiveness of experimental therapy with unifusol was assessed by changes in the arterial pressure level, duration of endothelium-dependent and -independent vasodilation, and the blood concentration of endothelial dysfunction markers including VEGF, NO, endothelin-I and the number of desquamated endotheliocytes. Administration of unifusol favors correction of blood vessel endothelium state manifested by normalization of its functional activity and reduction of the apoptosis of endotheliocytes. In addition, the obtained results unambiguously confirm considerable vasodilating and antihypertensive effects of unifusol.


Assuntos
Anti-Hipertensivos/uso terapêutico , Arginina/análogos & derivados , Arginina/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/toxicidade , Succinatos/uso terapêutico , Doenças Vasculares/tratamento farmacológico , Vasodilatadores/uso terapêutico , Animais , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Masculino , Óxido Nítrico/sangue , Ratos , Doenças Vasculares/sangue , Doenças Vasculares/fisiopatologia
7.
Opt Express ; 23(19): A1236-44, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26406752

RESUMO

We report on a band edge absorber/emitter design for high-temperature applications based on an unstructured tungsten substrate and a monolayer of ceramic microspheres. The absorber was fabricated as a monolayer of ZrO(2) microparticles on a tungsten layer with a HfO(2) nanocoating. The band edge of the absorption is based on critically coupled microsphere resonances. It can be tuned from visible to near-infrared range by varying the diameter of the microparticles. The absorption properties were found to be stable up to 1000°C.

8.
Antibiot Khimioter ; 59(9-10): 3-9, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25975108

RESUMO

The induction profile of endogenous interferons of three types under the action of meglumine acridone acetate and sodium acridone acetate, as well as the characteristics of the kinetics of their accumulation and circulation in the blood of experimental animals are described. Meglumine acridone acetate provided balance in induction, production and circulation of the interferons in the blood vs. sodium aeridone acetate under the same conditions. The optimal dose of meglumine acridone acetate (2.0-3.5 mg/mouse) with effective, consecutive and overlapping induction-production of the interferons ensured their prolonged (for 72 hours) circulation in the blood after a single administration.


Assuntos
Acridonas/administração & dosagem , Citocinas/biossíntese , Indutores de Interferon/administração & dosagem , Interferon-alfa/biossíntese , Interferon gama/biossíntese , Meglumina/administração & dosagem , Animais , Citocinas/sangue , Feminino , Interferon-alfa/sangue , Interferon gama/sangue , Camundongos , Camundongos Endogâmicos CBA , Fatores de Tempo
9.
Adv Mater ; 25(29): 4043-8, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23813784

RESUMO

Atomic engineering of perovskite films and interfaces is significantly improved by in situ optimization of reflection high-energy electron diffraction (RHEED) features resulting from surface BO6 octahedral rotations seen during molecular-beam epitaxy growth. This approach yields Sr-doped manganite films across the phase diagram with magnetotransport properties that are, for the first time, identical to bulk single crystals. Careful structural analysis of manganite/titanate interfaces shows that cation intermixing and unit cell dilations are eliminated, while BO6 rotations and Jahn-Teller-type elongations are nearly completely suppressed at the interface.


Assuntos
Compostos de Cálcio/química , Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Óxidos/química , Titânio/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
10.
Bull Exp Biol Med ; 136(6): 595-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15500082

RESUMO

Treatment of female SAMP-1 mice with Neuronol (drug containing succinic acid) given with drinking water starting from the age of 2 months during the whole life prolonged the lifespan and markedly reduced mortality of animals aged 1.5-2 years. Neuronol inhibited the development of spontaneous tumors, primarily lymphomas, and significantly prolonged lifespan in mice with tumors. Long-term treatment with Neuronol had no pathological side effects. Our experiments demonstrated geroprotective and anticarcinogenic activity of Neuronol and safety of its long-term use.


Assuntos
Envelhecimento/patologia , Anticarcinógenos/farmacologia , Longevidade/efeitos dos fármacos , Neoplasias Experimentais/tratamento farmacológico , Succinatos/farmacologia , Ácido Succínico/farmacologia , Animais , Anticarcinógenos/efeitos adversos , Avaliação Pré-Clínica de Medicamentos , Feminino , Histiocitoma Fibroso Benigno/tratamento farmacológico , Histiocitoma Fibroso Benigno/mortalidade , Histiocitoma Fibroso Benigno/patologia , Linfoma/tratamento farmacológico , Linfoma/mortalidade , Linfoma/patologia , Camundongos , Camundongos Endogâmicos , Neoplasias Experimentais/mortalidade , Neoplasias Experimentais/patologia , Succinatos/efeitos adversos
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