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Rapid changes in the hydrological and temperature regimes over the past decades at the northern latitudes enhance significantly permafrost degradation accelerating carbon release, increase the frequency of drought events and extensive wildfires. However, the mechanisms and dynamics driving drought events and their influence on Siberian forests are currently the subject of numerous research activities. Newly developed and annually resolved stable carbon and oxygen isotope chronologies of larch tree-ring cellulose (δ13Ccell and δ18Ocell) for the period 516–2009 CE allowed the reconstruction of July precipitation and Arctic Oscillation (AO) in May, respectively. Unprecedented drought events occurred towards twentieth–twenty-first centuries as indicated by the July precipitation reconstruction. Positive AO phases in May were most pronounced during the second part of the first millennium, but also increased in frequency in the modern period of the twentieth–twenty-first centuries. Negative AO phases are associated with cold anomalies and show a remarkable decrease in the nineteenth century caused by a series of major volcanic eruptions. Our findings help explaining the increased frequency of Siberian forest fires over the past decades in Central Siberia consistent with a reduction of summer precipitation, triggered by a positive phase of the Arctic Oscillation in May.

Russian and Soviet history of translation has undergone different stages of its development. Western literature in Russian translation played a significant role in forming the national literature (the so-called literary transplantation of the 18th century). Later, not only selection, but also non-selection of books/authors for translation played a canon-forming function. Social (historical, political, ideological) influence on translation was of a shifting nature, as it is shown by examples (such as Jane Austen). It also affected the process of selection/non-selection of books for translation. © 2021, Slovak academy of Sciences, Institute of World literature. All rights reserved.

Primary interjections consist of a group of prototypical units, which are associated with reflex cries by their origin, have an oral form called a vocal gesture, and written, conventional ones, with national characteristics. Analysis of similar features in pronunciation, spelling and semantics of prototypical units and linguistic differences of other units reveals universal characteristics of a limited number of prototypical interjections and linguistic specifity of the majority of primary interjections. Examples drawn from English, Russian and Kazakh languages demonstrate the ability of primary interjections to express the ambivalence of feelings and emotions. The article focuses on distinguishing instinctive and discursive categories of primary interjections concentrating on the mode of their production and purpose of use. The first category includes addressless exclamations that express a reaction to what is happening, as well as relevant feelings and emotions. The second group includes units that are explicitly or implicitly intended for the addressee of speech, which are used for communicative purposes. In contrast to instinctive interjections expressing spontaneous feelings and reactions, discursive units may reflect unreal emotions that the interlocutor expects to be demonstrated. In a pragmatic aspect, the use of primary interjections is considered to convey an ironic attitude to the subject of speech. The article provides an overview of language units that formally resemble primary interjections and make their identification difficult.

Human liver cancer research currently lacks in vitro models that can faithfully recapitulate the pathophysiology of the original tumor. We recently described a novel, near-physiological organoid culture system, wherein primary human healthy liver cells form long-term expanding organoids that retain liver tissue function and genetic stability. Here we extend this culture system to the propagation of primary liver cancer (PLC) organoids from three of the most common PLC subtypes: hepatocellular carcinoma (HCC), cholangiocarcinoma (CC) and combined HCC/CC (CHC) tumors. PLC-derived organoid cultures preserve the histological architecture, gene expression and genomic landscape of the original tumor, allowing for discrimination between different tumor tissues and subtypes, even after long-term expansion in culture in the same medium conditions. Xenograft studies demonstrate that the tumorogenic potential, histological features and metastatic properties of PLC-derived organoids are preserved in vivo. PLC-derived organoids are amenable for biomarker identification and drug-screening testing and led to the identification of the ERK inhibitor SCH772984 as a potential therapeutic agent for primary liver cancer. We thus demonstrate the wide-ranging biomedical utilities of PLC-derived organoid models in furthering the understanding of liver cancer biology and in developing personalized-medicine approaches for the disease.

In this paper, we report recent results obtained in the development of digital pulse processing mathematics for prompt fission neutron (PFN) investigations using a twin ionization chamber (TIC) along with a fast neutron time-of-flight detector (ND). Due to some ambiguities in the literature concerning a pulse induction on TIC electrodes by fission fragment (FF) ionization, we first presented a detailed mathematical analysis of FF signal formation on the TIC anode. The analysis was done using the Shockley–Ramo theorem, which gives the relation between charged particle motion between TIC electrodes and the so-called weighting potential. The weighting potential was calculated by direct numerical solution of the Laplace equation (neglecting space charge) for the TIC geometry and ionization caused by FFs. Formulae for GI correction and digital pulse processing algorithms for PFN time-of-flight measurements and pulse shape analysis are presented and used in experiments for PFN investigations of two reactions, [Formula: see text]U(n[Formula: see text],f) and [Formula: see text]Cf(sf). Results of the measurements were compared to literature data to demonstrate the feasibility of the new developed techniques. These results were necessary for the development of a new PFN investigation facility consisting of a position sensitive fission fragment detector combined with 32 liquid scintillation neutron detectors.

The measurement procedure based on the continuous thermal neutron beam modulation with a mechanical chopper was developed for delayed neutron yield measurement of the thermal neutron induced fission of [Formula: see text]Np. The idea of the procedure is similar to that widely used in modern computer communications to prevent unauthorized data access. The data is modulated with a predefined pattern before transmission to the public network, and only the recipient that has the modulation pattern is able to demodulate it upon receipt. For thermal neutron induced reaction applications, the thermal neutron beam modulation pattern was used to demodulate the measured delayed neutron intensity signals on the detector output, resulting in nonzero output only for the detector signals correlated with the beam modulation. The comparison of the method with the conventional measurement procedure was provided, and it was demonstrated that the cross-correlation procedure has special features making it superior to the conventional one, especially when the measured value is extremely small in comparison with the background. Due to the strong sensitivity of the measurement procedure on the modulation pattern of the neutron beam, one can implement the modulation pattern of a specific shape to separate the effect of the thermal part of the beam from the higher energy part in the most confident way in the particular experiment. The remarkable property of our method is related to the unique possibility of separation of the effects caused exclusively by thermal neutrons using the neutron time-of-flight measurement available on the IBR-2 pulsed reactor.

The prompt neutron emission in thermal neutron induced fission of 235U and spontaneous fission of 252Cf was investigated by using digital signal electronics. The goal was to check a new revised data analysis software with fission fragment (FF) kinetic energy corrections after prompt fission neutron (PFN) emission. The revised software was used to reanalyze old data measured in EC-JRC-IRMM, where 252Cf(sf) reaction was investigated. Both measurements were done using similar twin Frisch grid ionization chamber for fission fragment detection with equivalent NE213 fast neutron detector. About 0.5*106 FF with PFN coincidences have been analyzed in both measurements. The fission fragment kinetic energy, mass and angular distribution were investigated along with prompt neutron time of flight and pulse shape analysis using a six channel synchronous waveform digitizer (WFD) with sampling frequency of 250 MHz and 12 bit resolution in the 235U(nth,f) reaction. Similar WFD with sampling frequency of 100 MHz was used for PFN investigation in 252Cf(sf) reaction. These two experiments were considered as a reference for further investigations with a new setup composed of position sensitive ionization chamber to detect FF and an array of 32 liquid scintillators recently constructed in Dubna to detect neutrons.

In this article, we report the recent achievements in the design of a back-to-back twin ionization chamber (TIC) for fission fragment (FF) mass, kinetic energy, and orientation. Correlated FF kinetic energies, their masses, and the angle of the fission axes in 3D Cartesian coordinates can be determined from analysis of the heights and shapes of the pulses induced by the FFs on the anodes of the TIC. These anodes were designed to consist of isolated [Formula: see text]-shaped strips connected to nodes of a chain filter made of serially-connected two-port networks. The double charge division method was implemented by digitizing four waveforms at the endpoints of the chain filters. It was shown that the fission fragments emission point on the target plane may be determined using the measured data. A position-sensitive neutron-induced fission detector for neutron imaging applications with both thermal and low energy neutrons was found as another possible implementation of the designed TIC. Preliminary measurements with thermal neutron-induced fission were done with RC chain filters and the results are reported here.

The prompt neutron emission in thermal neutron induced fission of 235 U has been investigated applying digital signal electronics. The goal was to compare the results of this digital data acquisition and digital signal processing analysis to the results of the pioneering work of Apalin et al. Using a twin Frisch grid ionization chamber for the fission fragment detection and a NE213 equivalent neutron detector in total about 10 6 neutron coincidences have been registered. The fission fragment kinetic energy, mass and angular distribution has been investigated along with prompt neutron time of flight and pulse shape using a six channel synchronous waveform digitizer with sampling frequency of 250 MHz and 12 bit resolution. The signals have been analyzed using digital pulse processing algorithms, developed by authors. The thermal neutron beam was transported from the IBR-2 reactor to the target with bent mirror neutron guide.

Porins from outer membranes (OM) of Gram-negative bacteria exist in intact membranes as homotrimers forming water-filled pores or channels that provide low-molecular compounds transportation. Surface localization of the porins and their structural peculiarities determine multiplicity of their functions except for the transport one. On the one hand, porins are targets for the host immune system. As the targets they activate factors of the organism fast protection and are involved in the formation of specific immune response. On the other hand, porins serve as the factors of pathogenesis and virulence inhibiting the first stage of the host immune system and providing survival of a pathogen in macroorganism. Porins are speciesand genus-specific antigens of Gram-negative bacteria and belong to the highly immunogenic OM components. The antibodies against the porins are found in blood sera both after vaccination and after natural development of infection.

Photopheresis with blood lymphocytes UV radiation exposure was for the first time used in the treatment of patients with myasthenia. Twenty-three patients with generalized form of the disease, aged 23-66 years, were treated. Twenty patients (87%) exhibited clinical improvement after a treatment course (4 sessions). One photopheresis session was shown to be more or less beneficial in 16 out of 23 patients (70%). The treatment resulted in strengthening of all the muscles studied, especially of mimic, platysma, biceps, deltoid, illiopsoas and gastrocnemius. Photopheresis was effective not only in a mild and moderate but in severe form of myasthenia as well. Compared to plasmapheresis, photopheresis exerts a more prolonged effect. Clinical improvement correlated with positive changes in immune status of the patients.

The role of mutagenic factors in the onset of diffuse toxic goiter (DTG) was studied in 49 families of probands with DTG. The evidence obtained on the order in which the child was born in the proband's family, age of the parents at the time of DTG child delivery, implications of occupational factors in DTG onset does not rule out mutagenic effects in the origin of DTG and thus feasibility of the key gene influence on the disease predisposition.

Thymectomy was carried out in 52 children with the generalized form of myasthenia at the Moscow Regional Research Clinical Institute in 1986-1991. The long-term results were studied in 50 patients in follow-up periods of 6 months to 5 years. The follow-up was studied in all patients, the muscular strength in various groups of muscles was measured according to a 5-point scale, and the function of external respiration, neuromuscular conductivity, and cellular and humoral immunity were studied. After thymectomy the symptoms of myasthenia disappeared completely or diminished significantly, the decrement was 11% on the average instead of 37% as was before the operation, the external respiration values improved, the level of circulating immune complexes and immunoglobulins became normal. The long-term results were appraised according to G. Keanes' scale. Group A was made up of 22 patients, group B of 13, group C of 5, group D of 8, and group E of 2 patients. Thus, the study shows that thymectomy is the most effective method for the treatment of myasthenia in children today.

The authors describe the course of myasthenia in children whose mean age of the disease onset is 10.1 years (7.9 years in boys and 11.2 years in girls). All the children had generalized myasthenia. The use of plasmapheresis produced a beneficial effect in all the cases, especially in children with grave myasthenia.

Static disorders elicited by the adequate methods of the assessment of equilibrium (stabilography) and gait (plantography) in hereditary ataxias have been analyzed. These techniques of examination make it possible to quantitatively estimate motor disorders, supplement clinical findings and provide an opportunity for objective evaluation of the efficacy of the conducted therapy.

Twin pairs with one or two myasthenic patients were selected from patients with neuromuscular pathology. 18 couples of twins were included in final selection (9 monozygotic and 9 dizygotic pairs). 4 pairs of monozygotic twins were concordant to myasthenia (MA). All dizygotic pairs were discordant to this disease. Matched concordance of monozygotic twins was 44%. Penetration of pathological gene was 61% assuming the hypothesis about monogenic heredity of MA. The coefficient of heredity was 44%. The conclusion was made about important, but not absolute role of hereditary factors in development of MA. It was necessary the presence of combination of both genetic and environmental factors for MA development.

The distribution of ABO blood groups and rhesus factor was studied in patients with myasthenia as compared with the control. There was a statistically significant association of the diseases with the rhesus-negative phenotype and that of generalized myasthenia concurrent with thymoma with the B (III) blood group. The examination revealed no other determinants of the significant association with the disease. The values of a disease risk were obtained for persons having myasthenia-associated signs. It is concluded that the Rh-negative phenotype shows a 1.3-fold increase in the risk of the disease as compared with those having Rh-positive persons.

The article presents the analysis of coordination disorders detected by clinical tests and tests aimed at examining the reaction of following a spot of light and the technique of determining the degree of tremor in hereditary ataxias. It has been shown that the most marked alterations are observed when the nervous system is severely damaged. The methods employed make it possible to quantitatively assess motor disturbances, supplementing, therefore, the available clinical findings. They also permit objective evaluation of the efficacy of the conducted therapy.

Thymectomy was included in the complex of therapeutic measures in the management of generalized myasthenia in 41 children. Much attention was given to preoperative management in which plasmapheresis was applied along with the traditional methods. As a result, maximum compensation of the myasthenic disorders was achieved and spontaneous respiration was restored in 9 patients who were given artificial ventilation of the lungs before the operation. The authors describe the techniques of thymectomy and the changes found in the thymus during histological study. No complications occurred. All of the children were discharged from the clinic in an improved condition. The late-term results were studied in 38 children in follow-up periods of 6 months to 4 years. Marked stable improvement was recorded in 31 (77.5%) patients.

Hereditary spastic paraplegia (HSP), type 4, or SPG4, caused by various mutations in the spastin gene (SPAST) is the most common disorder in a heterogeneous group of autosomal dominant HSP's. We performed a search of SPAST mutations by routine methods (SSCP and subsequent direct sequencing of fragments with modified electrophoretic mobility) in a sample of 26 families with autosomal dominant HSP from different Russian regions. In six families, five of Russian and one of Tatar ethnicity, different SPAST mutations were detected. Three of the mutations, Arg431Stop, Gln280Arg FsX9 and Asn386Ser, were reported previously; the remaining three, Asp555Tyr, Thr369Thr and Asn184Thr, were novel. In the family with the Arg431Stop mutation, a linkage to SPG4 locus was also established, lod scores were 1,66 for D2S352 marker and 1,51 for D2S367. Another large family also showed a linkage to the SPG4 locus (lod scores 1,68 for D2S352, 2,17 for D2S367) but the mutation was not found which may be due to atypical SPAST mutations (large deletions etc) undetectable by routine methods of DNA analysis. Including this family, the proportion of the SPG4 in the sample is 27%, which is less than average literature data (40-45%). Most of our patients presented relatively late-onset "uncompicated" HSP, which was typical for SPG4, though different additional features in SPG4 patients were also known. One of our patients had very early-onset HSP and concomitant epilepsy. In two pedigrees, in which all available relatives were examined, some patients had mild signs of SPG4, even late in life.