We prove that the upper general exponents of all systems in the
-class of a system of linear differential equations with conditionally periodic coefficients are the same. The relation between these ...exponents and the spectral radius of the monodromy operator of the original system is indicated.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The “Operational Plan of the Baltic Sea Naval Forces in the event of the European War” dated 1912, with which the Russian Navy entered the First World War, is reviewed; the concept, operational ...structure, and tasks to the fleet units are analyzed. Strengths of the document include the principle of concentrating forces in a crucial line of action and complex use of heterogeneous forces; weaknesses are single-optionness, passive-expectant nature of actions, not quite rational operational formation of the fleet, lack of operational perspective, and poor coordination with ground forces and allies. The conclusion is made that the plan became a certain stage in the development of naval art and evidence of the creative approach to the search of forms and methods of “asymmetric” counteraction to a superior adversary. However, from the military and political point of view the document turned out to be untenable, as it was based on the only and, moreover, the least probable international political combination.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•Cancer-associated microRNAs can be detected with nanowire biosensor.•The concentration sensitivity of nanowire detection of microRNAs is ∼10−17 M.•Nanowire biosensor allows detecting an increase in ...miRNA level in breast cancer patients.
This work demonstrates the possibility of detection of DNA-oligonucleotide (oDNA) and microRNAs (miRNAs) extracted from blood plasma and associated with breast cancer (BC) in a buffer solution using the nanowire (NW) biosensor based on the silicon-on-insulator (SOI) structures. For biospecific detection, the NW surface was modified with oligonucleotide probes (oDNA-probes) complementary to the well-known miRNA sequence. It has been shown that the SOI-NW biosensor with immobilized oDNA-probes of this type can be used to detect complementary oDNA in a buffer solution with a concentration sensitivity of 10−17 М. The study also demonstrates the use of such biosensor for detection of an increased level of miRNAs isolated from the plasma of breast cancer patients. Application of the NW biosensor enables to distinguish between patients with a diagnosis of breast cancer from those with ovarian cancer (OC) by the value of an increased miRNAs level in the blood plasma of breast cancer patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The article discusses the construction of a computer model to predict the problems occurrence in students in the educational process at the university. The following data sources of Altai State ...University were used for this purpose: "Admissions Office" (enrollees database) and "Dean's office" (database of students) for 2013-2018. These data were combined using developed SQL scripts. While analyzing the obtained combined data set, we had to face the difficulties typical for solving data analysis problems. Thus, it turned out that there are incomplete and inconsistent data or cases when one and the same entity is named differently, etc. In order to solve these problems, we wrote a script in the R programming language using regular expressions, the data were unified and standardized, and the missing data were restored using the information from other fields of the data set. Then we discarded the variables with the near-zero dispersion, which could not make a significant contribution to the developed predictive model. After that, the data set under study was divided into 2 parts: the 2013-2017 data were taken to build a predictive model with the use of the logistic regression algorithm, while the data for 2018 were used, in fact, to predict whether a particular student would be expelled. It should be mentioned that the 2013-2017 data were divided into the training and test samples in the proportion of 90% and 10% correspondingly. The test result of the computer model built in the R programming language showed satisfactory accuracy; the most significant factors affecting student expulsion were also identified. The paper substantiates the economic feasibility of using the developed computer model at the university.
We study the existence of a conditionally periodic solution of a linear system with a Stepanov conditionally periodic inhomogeneity. We prove that if this system has a bounded solution, then almost ...every system in its
H
-class has a bounded Besicovitch conditionally periodic solution.
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CEKLJ, DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Photoluminescence (PL) of Lu2SiO5 crystal and ceramics with a high concentration of oxygen vacancies (0.1-0.5 at.%) is studied. Oxygen vacancies were created using two ways. The first method is a ...growth of crystal from the non-stoichiometric Lu2Si0.98O4.96 melt and the second one is a doping of Lu2SiO5 matrix with divalent Ca2+ ions at the concentration of 1 at.%. For the first time we observe a fairly bright room-temperature ultraviolet PL of both crystal grown from the Lu2Si0.98O4.96 melt with the composition Lu2Si0.996O4.992 and Lu2SiO5 ceramics doped with Ca2+ ions. A band at 290 nm in the PL spectrum of the crystal and a band at 283 nm in the PL spectrum of the calcium-doped ceramics are observed. The spectral and kinetic properties of these bands are close to each other. This fact indicates similar origins of these bands. The results of the work show that the studied ultraviolet luminescence is related to oxygen vacancies in lutetium oxyorthosilicate
•Bright luminescence from oxygen-deficient Lu2SiO5 at room-temperature is observed.•Emission at 280-290 nm is dipole-resolved and due to oxygen vacancies.•Parameters of the emission are close to STE luminescence from Lu2SiO5.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A new genus and species of bacteria capable of ammonium oxidation under anaerobic conditions in the presence of nitrite is described. The enrichment culture was obtained from the Moscow River silt by ...sequential cultivation in reactors with selective conditions for anaerobic ammonium oxidation. Bacterial cells were coccoid, ∼0.4 × 0.7 μm, with the intracellular membrane structures typical of bacteria capable of anaerobic ammonium oxidation (anammoxosome and paryphoplasm). The cells formed aggregates 5–25 μm in diameter (10 μm on average). They were readily adhered to solid surfaces. The cells were morphologically labile: they easily lost their content and changed their morphology during fixation for electron microscopy. The organism was capable of ammonium oxidation with nitrite. The semisaturation constants Ks for nitrite and ammonium were 0.38 mg N-NO
2
/L and 0.41 mg N-NH
4
/L, respectively. The maximal nitrite concentrations for growth were 90 and 75 mg N-NO
2
/L for single and continuous application, respectively. The doubling time was 32 days, μ
max
= 0.022 day
−1
, the optimal temperature and pH were 20°C and 7.8–8.3, respectively. According to the results of 16S rRNA gene sequencing, the bacterium was assigned to a new genus and species within the phylum
Planctomycetes
. The proposed name for the new bacterium is
Candidatus
Anammoximicrobium moscowii gen. nov., sp. nov. (a microorganism carrying out anaerobic ammonium oxidation, isolated in the Moscow region).
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
It is found that the emission intensity of the 2
+
band system of the N
2
molecule (C
3
Π
u
→ B
3
Π
g
transition) under electron bombardment of pyrolytic aerogel SiO
2
in air at atmospheric pressure ...is 40–70% higher than that in the case of bombardment of aluminum under the same conditions. The dependences of the emission intensity at 337 nm (0-0 vibrational transition in the 2+ band system of the N
2
molecule) on the target temperature in the range of 30–60°C are different for the aluminum and SiO
2
targets, which indicates different excitation mechanisms of the N
2
(C
3
Π
u
) state. It is suggested that when the SiO
2
target is bombarded, the N
2
(C
3
Π
u
) state is excited not only by direct collisions with the electrons of the primary beam and secondary electrons, but also by the energy transfer from SiO
2
excitons and conduction electrons to N
2
molecules upon their contact with the SiO
2
surface.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We study the luminescence decay times of Ce
3+
: Lu
2
SiO
5
scintillator, co-doped with Sc
3+
and Li
+
ions, under the direct photoexcitation of Ce
3+
ions at 337 nm and excitation by a pulsed ...electron beam with energies of 100 – 300 keV. The cathodoluminescence (CL) and photoluminescence (PL) decay times of studied sample are equal within the experimental error. Two emission bands are found: in the range of 370 – 480 nm (“high-energy band”) and 500 – 570 nm (“low-energy band”). The highenergy emission band has the decay times
∼
40 ns. The low-energy emission band has the maximum decay time
∼
60 ns at 545 nm. The observed results show that the transport stage of Li:Sc:Ce:Lu
2
SiO
5
scintillation mechanism is not affected by a high negative space charge and high density of electronic excitations provided by the high-power electron beam.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Scintillation properties of a single-crystal Lu
2 –
x
Y
x
SiO
5
:Ce
3+
:Ca
2+
plate are compared with properties of a fine powder and a composite based on this powder, produced from the second part ...of this plate. A significant decrease in the decay time of the scintillation pulse in the powder sample is explained by the effect of the increased air—crystal side surface in comparison with the single crystal. In the Lu
2 –
x
Y
x
SiO
5
:Ce
3+
:Ca
2+
composite scintillator, the side surface of each particle contacts on all sides to polystyrene; therefore, the energy transfer of electron-hole pairs occurs without significant loss along the microcrystal surface without decreasing the luminescence time of cerium Ce
3+
ions.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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