197 research outputs found
Method for Characterization of Nano-Films Mechanical Properties
The new measuring procedure of nanosized films mechanical characteristics is proposed. The method
provides laying of an explored material film on a surface of getter which containing gas. A film is locally
deformed to bubbles formation by gassing from getter. Mechanical properties of nanofilm are calculated by
measuring the sizes and the shape of the undamaged and destroyed bubbles. Mechanical properties of iron
nanofilm with thickness 30 nanometers were determined by the method.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3517
Particle Creation from Vacuum by Lorentz Violation
It is shown that the vacuum state in presence of Lorentz violation can be
followed by a particle-full universe that represents the current status of the
universe. In this model the modification in dispersion relation (Lorentz
violation) is picked up representing the regime of quantum gravity. The result
can be interpreted such that the existence of the particles is an evidence for
quantum effects of gravity in the past. It is concluded that only the vacuum
state is sufficient to appear the matter fields spontaneously after the process
of semi-classical analysis.Comment: 9 pages, 2 figure
Advances in ab-initio theory of Multiferroics. Materials and mechanisms: modelling and understanding
Within the broad class of multiferroics (compounds showing a coexistence of
magnetism and ferroelectricity), we focus on the subclass of "improper
electronic ferroelectrics", i.e. correlated materials where electronic degrees
of freedom (such as spin, charge or orbital) drive ferroelectricity. In
particular, in spin-induced ferroelectrics, there is not only a {\em
coexistence} of the two intriguing magnetic and dipolar orders; rather, there
is such an intimate link that one drives the other, suggesting a giant
magnetoelectric coupling. Via first-principles approaches based on density
functional theory, we review the microscopic mechanisms at the basis of
multiferroicity in several compounds, ranging from transition metal oxides to
organic multiferroics (MFs) to organic-inorganic hybrids (i.e. metal-organic
frameworks, MOFs)Comment: 22 pages, 9 figure
Seasonal changes in milk quality indicators jersey cows
The article presents the results of studies of milk quality indicators: the mass fraction of fat, the mass fraction of protein and the number of somatic cells in the Jersey breed in the Stavropol Territory in 2022-2023. In the autumn period, the indicators of the mass fraction of fat and protein were higher compared to other seasons and equal to 6.08% and 4.66%, respectively. The number of somatic cells was also increased in the autumn and spring periods of 140 and 146 thousand units/ml, respectively. A significant negative correlation of the mass fraction of protein and average daily productivity to the number of somatic cells r = -0.21 and -0.12 was established. And a significant positive correlation between the mass fraction of fat and the level of somatic cells r = 0.52
Results of surgical treatment of early-onset scoliosis using growth-friendly implants: analysis of a 10-year monocentric cohort
Objective. To evaluate early and medium-term results of surgical treatment of early-onset scoliosis using the principle of growth-friendly systems.
Material and Methods. A retrospective analysis of the medical records of 54 patients treated using surgical distractible metal implants was
carried out. Patients were divided into 4 etiological groups: congenital (n = 17), systemic (n = 12), idiopathic (n = 16) and neurogenic
scoliosis (9). The boy/girl ratio was 11/43. The average age at which patients started treatment was 9.6 years, and at the end of treatment – 13.2 years.
Results. Radiometric parameters were assessed during and after completion of treatment. The Cobb angle of the main curve of deformity before treatment averaged 56.1°, after the primary operation – 31.8°, and after completion of treatment – 23.2°. Correction of the main deformity curve for the entire period of multi-stage surgical treatment was 57.8 %. The highest initial magnitude of deformity was noted in the group of neuromuscular scoliosis (67.6°), and the lowest in the group of congenital pathology (50.4°). In the groups of systemic and idiopathic scoliosis, the preoperative values were very close: 53.4° for systemic scoliosis and 57.6° for idiopathic scoliosis. According to the results of staged treatment in the neuromuscular scoliosis group, the residual curvature of the main curve was the lowest, and the percentage of its correction was the highest – 18.9° and 73.6 %, respectively, versus 24.5° and 49.7 % in the congenital scoliosis group.
The effectiveness of treatment with an assessment of the percentage of correction after final instrumentation in groups of idiopathic and
systemic scoliosis was close: 23,0° and 62.3 %, and 28.5° and 51.5 %, respectively. Identical average values of the main curve angle after
final instrumentation were noted in all four etiological groups (on average, 23.2°). Changes in thoracic kyphosis and lumbar lordosis were insignificant. During the treatment, 22 unplanned surgical interventions were performed in 15 patients.
Conclusion. This study revealed a number of key points that in the future may help in the formation of clearer algorithms of selecting the
most optimal technique: neurogenic scoliosis is most successfully corrected by growing systems, and congenital scoliosis shows less pronounced correction of deformity and a greater relative number of complications per patient with a single use of growing systems, which
requires caution during staged surgical treatment
Search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state in proton-proton collisions at s=13TeV
A search for new heavy resonances decaying to WW, WZ, ZZ, WH, or ZH boson pairs in the all-jets final state is presented. The analysis is based on proton-proton collision data recorded by the CMS detector in 2016–2018 at a centre-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 138 fb−1. The search is sensitive to resonances with masses between 1.3 and 6TeV, decaying to bosons that are highly Lorentz-boosted such that each of the bosons forms a single large-radius jet. Machine learning techniques are employed to identify such jets. No significant excess over the estimated standard model background is observed. A maximum local significance of 3.6 standard deviations, corresponding to a global significance of 2.3 standard deviations, is observed at masses of 2.1 and 2.9 TeV. In a heavy vector triplet model, spin-1 Z′ and W′ resonances with masses below 4.8TeV are excluded at the 95% confidence level (CL). These limits are the most stringent to date. In a bulk graviton model, spin-2 gravitons and spin-0 radions with masses below 1.4 and 2.7TeV, respectively, are excluded at 95% CL. Production of heavy resonances through vector boson fusion is constrained with upper cross section limits at 95% CL as low as 0.1 fb. © 2023 The Author(s
Search for a heavy composite Majorana neutrino in events with dilepton signatures from proton-proton collisions at √s=13 Tev
Results are presented of a search for a heavy Majorana neutrino N ⠃ decaying into two same-flavor leptons ⠃ (electrons or muons) and a quark-pair jet. A model is considered in which the N ⠃ is an excited neutrino in a compositeness scenario. The analysis is performed using a sample of proton-proton collisions at & RADIC;s = 13 TeV recorded by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 138 fb-1. The data are found to be in agreement with the standard model prediction. For the process in which the N ⠃ is produced in association with a lepton, followed by the decay of the N ⠃ to a same-flavor lepton and a quark pair, an upper limit at 95% confidence level on the product of the cross section and branching fraction is obtained as a function of the N ⠃ mass mN ⠃ and the compositeness scale ⠄. For this model the data exclude the existence of Ne (N & mu;) for mN ⠃ below 6.0 (6.1) TeV, at the limit where mN ⠃ is equal to ⠄. For mN ⠃ N 1 TeV, values of ⠄ less than 20 (23) TeV are excluded. These results represent a considerable improvement in sensitivity, covering a larger parameter space than previous searches in pp collisions at 13 TeV.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3
The ability to measure the temperature of the frozen active topsoil of the Arctic tundra based on ALOS PALSAR data
The temperature dependence of the radar backscattering coefficient on a horizontal-horizontal polarization, measured by the SAR ALOS over the territory Samolovsky Island, are studied in the paper. In article was shown, the temperature dependence of the backscattering coefficient on the horizontal-horizontal polarization is strongly correlated with soil temperature measured at a depth of 5 cm
Two approaches to the analysis of spatial and temporal organizations of a literary work (M.M. Bakhtin and V.M. Zhirmunsky)
This article examines two methodologies for analyzing a literary work. The first one was developed by M.M. Bakhtin on the basis of a broad aesthetic and philosophical approach; the second one was developed by V.M. Zhirmunsky on the basis of a more specific formal and poetological approach. These methodologies were applied by both researchers to A.S. Pushkin’s poems in the 1920s. It is argued that Bakhtin’s methodology was worked out in opposition to the main provisions of Zhirmunsky, who was close to the position of Russian formalism, also taking into account L.V. Shcherba’s achievements in the field of the linguistic analysis of a poetic text. This article describes the fundamental differences in the methodological conceptions of the philosopher and the literary critic concerning the nature of verbal creativity and understanding of the spatial and temporal organization of a literary work. The comparison of two analyses of Pushkin’s poem “For the Shores of Distant Homeland…”, shows that Zhirmunsky reduces the spatial and temporal aspects of a work of art to the compositional arrangement of verbal and sound material, since he considers verbal creativity as a linguistic phenomenon, while Bakhtin refers to the space and time of aesthetic reality, drawing a distinction between the composition and the architectonics of the literary work. It appears that the philosopher perceives the work as a field of dialogue between various subjects of consciousness (the author, the characters, the reader), while the literary critic proceeds from the author’s primacy as creator of a system of artistic techniques, giving the reader a position of passive perception. It is concluded that both methods of analysis complement each other organically, Zhirmunsky analyzing the verbal-compositional dimensions of a literary work and Bakhtin its objective-architectonic dimension.</jats:p
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