Publications by authors named "V P Kovalev"

The initial electron transfer (ET) processes in reaction centers (RCs) of Chloroflexus (Cfl.) aurantiacus were studied at 295 K using femtosecond transient absorption (TA) difference spectroscopy. Particular attention was paid to the decay kinetics of the primary electron donor excited state (P) and the formation/decay of the absorption band of the monomeric bacteriochlorophyll a anion (B) at ~ 1035 nm, which reflects the dynamics of the charge-separated state PB.

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Spinal cord stimulation is a well-established, minimally invasive surgical technique that has been effectively utilized for the treatment of chronic pain syndromes. In the past 15 years, there has been a significant increase in reports on the use of spinal stimulation for patients with advanced Parkinson's disease (PD), as well as in isolated cases of atypical parkinsonism. These reports frequently highlight a positive impact of spinal stimulation on gait impairments.

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Article Synopsis
  • Drug resistance in cancer chemotherapy is a major issue, with cancer cells often shifting to fatty acid metabolism to evade treatment.
  • The researchers created a drug called folate-polySia (FpSA) that induces microcalcification in cervical cancer cells resistant to cisplatin, leading to decreased fatty acid uptake and increased glycolysis.
  • The combination of cisplatin and FpSA not only inhibited tumor growth but also improved survival rates in mice, suggesting a new strategy to tackle chemotherapy-resistant tumors by reprogramming cancer cell metabolism.
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In the framework of the Floquet theory of periodically driven quantum systems, it is demonstrated that irradiation of graphene by a circularly polarized electromagnetic field induces an attractive area in the core of repulsive potentials. Consequently, the quasi-stationary electron states bound by the repulsive potentials appear. The difference between such field-induced states in graphene and usual systems with the parabolic dispersion of electrons is discussed and possible manifestations of these states in electronic transport and optical spectra of graphene are considered.

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The anhydrous beryllium carbonate Be[CO] with calcite-type crystal structure was obtained by a reaction of BeO with CO in a laser-heated diamond anvil cell at pressures between 30 GPa and 80 GPa and elevated temperatures. Its calcite-type crystal structure (3̅ with = 6) is characterized by 6-fold-coordinated beryllium atoms forming [BeO] octahedra and by trigonal-planar [CO] groups. The crystal structure was determined by synchrotron-based single-crystal X-ray diffraction and confirmed by density-functional-theory-based calculations in combination with experimental Raman spectroscopy.

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