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1.
Phys Chem Chem Phys ; 22(43): 25243-25254, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33135705

RESUMO

Using an exciton as a carrier was examined as a possible solution to the problem of signal transmission between molecular logic gates. A tetrathiafulvalene chain was chosen as a model for a molecular logic system and its distinct logic states were described as excitons located at certain tetrathiafulvalene units. The parameters of the exciton transfer between the units of the chain were studied. The transfer rate between the two adjacent units was calculated using the Plotnikov-Bixon-Jortner theory basing on molecular parameters calculated using TD-DFT. The order of electronic states was studied at the MCQDPT and TD-DFT levels of theory. It was found that certain functional groups in the chain can make exciton transfer faster than its recombination. The exciton can effectively carry a signal through the chain, which in turn can be enlarged and modified.

2.
Nanoscale ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037702

RESUMO

Molecular logic gates (MLGs) are molecules which perform logic operations. They can potentially be used as building blocks for nano-sized computational devices. However, their physical and functional integration is a difficult task which remains to be solved. The problem lies in the field of signal exchange between the gates within the system. We propose using non-adiabatic excitation transfer between the gates to address this problem while absorption and fluorescence are left to communicate with external devices. Excitation transfer was studied using the modified Bixon-Jortner-Plotnikov theory with the example of the 3H-thioxanthene-TTF-dibenzo-BODIPY covalently linked triad. Several designs of the molecule were studied in a vacuum and cyclohexane. It was found that the molecular logic system has to be planar and rigid to isolate radiative interfaces from other gates. Functioning of these gates is based on dark πσ*-states in contrast to bright ππ*-states of radiative interfaces. There are no fundamental differences between ππ* → πσ* and ππ* → ππ* transitions for cases when an exciton hops from one gate to another. The rates of such transitions depend only on an energy gap between states and the distance between gates. The circuit is highly sensitive to the choice of solvent which could rearrange its state structure thereby altering its behavior. According to the obtained results, non-adiabatic transfer can be considered as one of the possible ways for transmitting a signal between MLGs.

3.
Artigo em Russo | MEDLINE | ID: mdl-24640658

RESUMO

The present review describes the modern methods for the combined treatment and rehabilitation of the patients presenting with arterial hypertension and their influence on the key pathogenetic components of this condition in accordance with the currently accepted theories of its origin and evolution. The discovery of specific molecular and cellular mechanisms of the therapeutic action of certain factors that reflect peculiar and unique character of their inherent physical energy provided a basis for the development of highly effective methods for the treatment and prevention of arterial hypertension and rehabilitation of the patients suffering this disease. The most comprehensive clinical effect is produced by the application of scientifically sound therapeutic systems; exclusion of certain therapeutic physical factors from these modalities results in s significant reduction of their curative effectiveness.


Assuntos
Hipertensão/prevenção & controle , Hipertensão/reabilitação , Humanos , Hipertensão/etiologia , Terapia com Luz de Baixa Intensidade , Magnetoterapia , Modalidades de Fisioterapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Reflexoterapia , Resultado do Tratamento
4.
Artigo em Russo | MEDLINE | ID: mdl-21381322

RESUMO

The objective of the present work was to develop methods and a scientifically sound rationale for the optimization of clinical results of the treatment of patients presenting with arterial hypertension (AH) associated with coronary heart disease (CHD) using red and infra-red (IR) low-intensity laser irradiation. The study included a total of 90 patients of working age (62.2% of men and 37.8% of women) having AH associated with coronary heart disease and abnormal blood lipid spectrum. They were allocated to three groups each comprising 30 patients matched for age, sex, severity of clinical conditions, and character of maintenance medicamental therapy. Patients of group 1 were treated by intravenous blood irradiation with laser light; those in group 2 were given similar treatment in combination with external low-intensity IR laser therapy; patients of group 3 received basal medicamental therapy. The study allowed the clinical value of different variants of low-intensity laser therapy to be assessed as regards efficiency of correction of hypersympaticotony, disturbances of lipid metabolism, and refractoriness to pharmaceutical products as well as improved tolerance of physical exercises, anti-hypertensive, anti-ischemic, and anti-anginal effects, diastolic function, and quality of life as targets of the comprehensive rehabilitative program designed for patients with AH associated with coronary heart disease. An optimized therapeutic modality is proposed for patients presenting with these pathologies based on the application of the low-intensity laser irradiation regime characterized by mutual amplification and complementary action of red and infrared lights.


Assuntos
Procedimentos Endovasculares/métodos , Hipertensão/radioterapia , Terapia com Luz de Baixa Intensidade , Isquemia Miocárdica/radioterapia , Terapia Combinada , Feminino , Humanos , Hipertensão/sangue , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Lipídeos/sangue , Masculino , Isquemia Miocárdica/sangue , Isquemia Miocárdica/complicações , Isquemia Miocárdica/tratamento farmacológico , Resultado do Tratamento
5.
Artigo em Russo | MEDLINE | ID: mdl-2728704

RESUMO

At the area of a natural focus of leptospirosis (caused by L. pomona) in the Mozdok region of the North Occetic ASSR leptospires were detected by the method of dark field microscopy in 22% of intact soil samples. The presence of pathogenic leptospires in this soil was not confirmed by the method of the biological assay on Syrian golden hamsters. In controlled tests lasting 1-277 days, in 30.4% of cases L. pomona retained their viability, pathogenic and antigenic properties for as long as 74 days, while staying in the soil at the focus of infection with humidity being 15.2-31.4% and pH = 6.7-7.2. 11 Leptospira cultures isolated after staying in the soil retained their pathogenic properties and the death of the animals used in the bioassay from the acute form of leptospiral infection.


Assuntos
Leptospira , Microbiologia do Solo , Animais , Cricetinae
6.
Chem Commun (Camb) ; 50(24): 3166-8, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24516860

RESUMO

A copper-promoted reductive homocoupling reaction, for the first time used for a metal complex, allowed obtaining a new kind of complexes with the encapsulated metal ions, C-C conjugated bis-clathrochelates. These compounds demonstrate extremely high transcription inhibition activity in the T7 RNA polymerase system with values of IC50 reaching as low as the submicromolar range, which places them among the most potent metal-based transcription inhibitors.


Assuntos
Quelantes/farmacologia , Cobre/química , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Compostos Ferrosos/farmacologia , Transcrição Gênica/efeitos dos fármacos , Proteínas Virais/antagonistas & inibidores , Quelantes/síntese química , Quelantes/química , RNA Polimerases Dirigidas por DNA/genética , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Compostos Ferrosos/síntese química , Compostos Ferrosos/química , Estrutura Molecular , Compostos Organometálicos/química , Oxirredução , Relação Estrutura-Atividade , Transcrição Gênica/genética , Proteínas Virais/genética
7.
Nat Commun ; 5: 4538, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-25066810

RESUMO

The precise measurement of forces is one way to obtain deep insight into the fundamental interactions present in nature. In the context of neutral antimatter, the gravitational interaction is of high interest, potentially revealing new forces that violate the weak equivalence principle. Here we report on a successful extension of a tool from atom optics--the moiré deflectometer--for a measurement of the acceleration of slow antiprotons. The setup consists of two identical transmission gratings and a spatially resolving emulsion detector for antiproton annihilations. Absolute referencing of the observed antimatter pattern with a photon pattern experiencing no deflection allows the direct inference of forces present. The concept is also straightforwardly applicable to antihydrogen measurements as pursued by the AEgIS collaboration. The combination of these very different techniques from high energy and atomic physics opens a very promising route to the direct detection of the gravitational acceleration of neutral antimatter.

8.
Dalton Trans ; 41(20): 6078-93, 2012 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-22453677

RESUMO

The cycloaddition of the mono- and dichloroglyoximes to the cobalt(II) bis-α-benzyldioximate afforded the cobalt(II) mono- and dichloroclathrochelates in moderate yields (40-60%). These complexes undergo nucleophilic substitution of their reactive chlorine atoms with aliphatic amines, alcohols and thiolate anions. In the case of ethylenediamine and 1,2-ethanedithiol, only the macrobicyclic products with α,α'-N(2)- and α,α'-S(2)-alicyclic six-numbered ribbed fragments were obtained. The cobalt(II) cage complexes with terminal mercapto groups were synthesized using aliphatic dithiols. The crystal and molecular structures of the six cobalt(II) clathrochelates were obtained by X-ray diffraction. Their CoN(6)-coordination polyhedra possess a geometry intermediate between a trigonal prism and a trigonal antiprism, and the encapsulated cobalt(II) ions are shifted from their centres due to the structural Jahn-Teller effect with the Co-N distances varying significantly (by 0.10-0.26 Å). The electrochemistry of the complexes obtained was studied by cyclic voltammetry (CV). The anodic waves correspond to the quasi-reversible Co(2+/3+) oxidations, whereas the cathodic ranges contain the quasi-reversibile waves assigned to the Co(2+/+) reductions; all the cobalt(i)-containing clathrochelate anions formed are stable in the CV time scale. The electrocatalytic properties of the cobalt complexes obtained were studied in the production of hydrogen from H(+) ions: the addition of HClO(4) resulted in the formation of the same catalytic cathodic reduction Co(2+/+) waves. The controlled-potential electrolysis with gas chromatography analysis confirmed the production of H(2) in high Faraday yields. The efficiency of this electrocatalytic process was enhanced by an immobilization of the complexes with terminal mercapto groups on a surface of the working gold electrode.

9.
Dalton Trans ; 41(3): 737-46, 2012 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21897962

RESUMO

The nucleophilic substitution of six chlorine atoms of the n-butylboron-capped clathrochelate iron and cobalt(II) precursors with perfluoroarylthiolate anions afforded the hexaperfluoroarylsulfide macrobicyclic iron and cobalt(II) tris-dioximates. The complexes obtained are soluble in aromatic and aliphatic hydrocarbons as well as in polar aprotonic solvents due to the presence of the superhydrophobic fluorine-containing molecular periphery. As it follows from the X-ray data for five iron and cobalt mono- and bis-clathrochelates, the geometry of their macrobicyclic frameworks is affected by both the nature of an encapsulated metal ion and that of the ribbed substituents. Bis-capping fragment Co(II)O(6) of the Co(III)Co(II)Co(III) bis-clathrochelate possesses a trigonal antiprismatic geometry, all the Co(II)N(6) coordination polyhedra are trigonal-prismatic, and those of the encapsulated iron(II) and cobalt(III) ions are intermediate between them. The wide range of Co-N distances as well as the significant shifts of the encapsulated cobalt(II) ions from the centres of their N(6)-coordination polyhedra were explained by the Jahn-Teller distortion. The EPR and magnetometry data are also characteristic of the low-spin cobalt(II) complexes with this distortion. The parameters of the (57)Fe Mössbauer spectra of the iron macrobicycles are characteristic of the low-spin iron(II) complexes. The cyclic voltammograms (CVs) for the complexes studied contain the one-electron oxidation and reduction waves assigned to metal-centered redox-processes. The Fe(2+/3+) and Co(2+/3+) oxidations are quasi-reversible or irreversible. The anionic clathrochelate species resulting from the reversible Co(2+/+) reductions are stable on the CV time scale, whereas their iron(I)-containing analogs are unstable.

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