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Endohedral fullerenes with paramagnetic encapsulated atoms are new magnetic materials of interest for numerous applications from medicine to quantum computers. An important phenomenon with endohedral fullerenes is the appearance of new vibrational frequencies not associated with empty fullerenes. The vibrational spectra of the lanthanide endohedral fullerenes La@C60 and Ce@C60 in various spin states are calculated using the density functional method. Most of the spectral lines lie in the 300-1600 cm-1range, and their intensities change dramatically depending on the molecule's symmetry and spin state, which are determined by the encapsulated lanthanide atom. The average frequency shift of the carbon cage vibrations caused by spin transition is only 5 cm-1. The calculated frequencies of the coupled "metal-carbon cage" vibrations of the lanthanide endohedral fullerenes La@C60 and Ce@C60 in various spin states lie in the 10-170 cm-1range. The computational results for both the frequencies and intensities of the metal-cage modes depend considerably on the spin state. The changes in these vibrational modes are due to the changes in the molecular symmetry and the metal-carbon bond lengths. Such dependence can be used as a basis for controlling the spin state of metallofullerenes by measuring the vibration frequencies in the far-infrared zone, which could be important for nanoelectronics and quantum informatics.

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BACKGROUND: Preservation of anatomic integrity and function of the cranial nerves during the removal of skull base tumors is one of the most challenging procedures in endoscopic endonasal surgery. It is possible to use intraoperative mapping and identification of the cranial nerves in order to facilitate their preservation.The purpose of this study was to evaluate the effectiveness of intraoperative trigger electromyography in prevention of iatrogenic damage to the cranial nerves. METHODS: Twenty three patients with various skull base tumors (chordomas, neuromas, pituitary adenomas, meningiomas, cholesteatomas) underwent mapping and identification of cranial nerves during tumor removal using the endoscopic endonasal approach in Department of Neurooncology of Federal State Autonomous Institution "N.N. Burdenko National Medical Research Center of Neurosurgery" of the Ministry of Health of the Russian Federation from 2013 to 2018. During the surgical interventions, mapping and identification of the cranial nerves were carried out using electromyography in triggered mode. The effectiveness of the method was evaluated based on a comparison with a control group (41 patients). RESULTS: In the main group of patients, 44 nerves were examined during surgery using triggered electromyography. During the study, the III, V, VI, VII, and XII cranial nerves were identified intraoperatively. Postoperative cranial nerve deficiency was observed in 5 patients in the study group and in 13 patients in the control group. The average length of hospitalization was 9 days. CONCLUSION: We did not receive statistically significant data supporting the fact that intraoperative identification of cranial nerves using trigger electromyography reduces the incidence of postoperative complications in the form of cranial nerve deficits (p = 0.56), but the odds ratio (0.6) suggests a less frequent occurrence of complications in the study group.Based on our experience, the trigger electromyography methodology appears quite promising and requires further research.

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We study optical losses in the single-mode fiber system with an all-optical switch based on the anisotropic acousto-optic (AO) TeO(2) 2D deflector. It is shown, theoretically and experimentally, that the mismatch of the output-fiber mode profile and the switched optical beam shape depends significantly on the monochromaticity of the light beam and is determined by the frequency dispersion of the laser beam diffracted on a Bragg AO cell. A quantitative analysis of the dependence of the input optical losses on the spectral width of the light beam is presented.

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The search for new methods in the control of purulent infection is highly topical nowadays. For this purpose a complex of intensive therapy is suggested involving hemosorption via the patient's blood perfusion through porcine heterospleen. By literature and experimental data this technique is not inferior in efficacy to the use of the donor spleen. The spleen is removed conventionally, in modification of the authors. The results of the hemosorption analysed on 82 procedures performed in 1989-1990 justify employment of the above hemosorption in view of its efficacy, availability, simplicity.

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Biohemosorption by means of extracorporeal connection of heterogeneous spleen renders not only powerful detoxic action, but intensive immunomodulation action as well. Swine spleen used for biohemosorption possess high bacterisorptive and immunomodulating potential. The cases of persistent course of disease, development of antibacterial therapy, grave condition of a patient serve as an indication for application of extracoproreal connection of heterogeneous spleen within the complex of intensive therapy. During 1989 in the hospital were treated 9 patients with osteomyelitis and extensive suppurative foci of soft tissues of the locomotor apparatus, complicated by severe sepsis. Those patients were applied to totally II extracorporeal connections of heterogeneous spleen and 8 biohemosorptions by means of heterogeneous spleen sections. In general, intensive therapy with application of extracorporeal connection of heterogeneous spleen was effective enough. All patients with no exception left hospital in satisfactory condition in 28-56 days after the beginning of treatment.

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